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Tiberius Brastaviceanu

Open Source 3-D Printed Nutating Mixer - Appropedia, the sustainability wiki - 0 views

www.appropedia.org/rce_3-D_Printed_Nutating_Mixer

open science open hardware OSH catalog

shared by Tiberius Brastaviceanu on 10 Oct 23 - No Cached
  • Tiberius Brastaviceanu on 10 Oct 23
     
    "As the open source development of additive manufacturing has led to low-cost desktop three-dimensional (3-D) printing, a number of scientists throughout the world have begun to share digital designs of free and open source scientific hardware. Open source scientific hardware enables custom experimentation, laboratory control, rapid upgrading, transparent maintenance, and lower costs in general. To aid in this trend, this study describes the development, design, assembly, and operation of a 3-D printable open source desktop nutating mixer, which provides a fixed 20° platform tilt angle for a gentle three-dimensional (gyrating) agitation of chemical or biological samples (e.g., DNA or blood samples) without foam formation. The custom components for the nutating mixer are designed using open source FreeCAD software to enable customization. All of the non-readily available components can be fabricated with a low-cost RepRap 3-D printer using an open source software tool chain from common thermoplastics. All of the designs are open sourced and can be configured to add more functionality to the equipment in the future. It is relatively easy to assemble and is accessible to both the science education of younger students as well as state-of-the-art research laboratories. Overall, the open source nutating mixer can be fabricated with US$37 in parts, which is 1/10th of the cost of proprietary nutating mixers with similar capabilities. The open source nature of the device allow it to be easily repaired or upgraded with digital files, as well as to accommodate custom sample sizes and mixing velocities with minimal additional costs."
Kurt Laitner

Are you ready for 3-D printing? | McKinsey & Company - 0 views

www.mckinsey.com/...are_you_ready_for_3-d_printing

3d printing mckinsey additive

shared by Kurt Laitner on 24 Feb 15 - No Cached
  • But patent expirations and new entrants in Asia should apply downward pressure over the next ten years
  • The cost of materials ought to drop in the long term as third-party firms become credible alternative powder suppliers and as increased demand for powder enhances scale efficiencies more generally
  • Throughput rates are expected to increase on the back of growing laser power, higher numbers of lasers, and better projection technology. All of that will serve to reduce expensive machine time
  • Kurt Laitner on 24 Feb 15
     
    Overly focused on additive 3d printing (the ecosystem of automated fabrication (ie fablab scale) and its exponential cost decreases are far more interesting).  The expiration of patents in the space is also a key feature of the current transformation, and should prompt discussions of dysfunctional IPR.  Comments on costs trends are also supportive.  No mention of the next big thing which is cradle to cradle desktop manufacturing.
Tiberius Brastaviceanu

Access control - Wikipedia, the free encyclopedia - 0 views

en.wikipedia.org/...Access_control

blockchainaccess_project wikipedia paper access passport IoPA tech

shared by Tiberius Brastaviceanu on 09 Jun 16 - No Cached
  • The act of accessing may mean consuming, entering, or using.
  • Permission to access a resource is called authorization.
  • Locks and login credentials are two analogous mechanisms of access control.
  • ...26 more annotations...
  • Geographical access control may be enforced by personnel (e.g., border guard, bouncer, ticket checker)
  • n alternative of access control in the strict sense (physically controlling access itself) is a system of checking authorized presence, see e.g. Ticket controller (transportation). A variant is exit control, e.g. of a shop (checkout) or a country
  • access control refers to the practice of restricting entrance to a property, a building, or a room to authorized persons
  • can be achieved by a human (a guard, bouncer, or receptionist), through mechanical means such as locks and keys, or through technological means such as access control systems like the mantrap.
  • Physical access control is a matter of who, where, and when
  • Historically, this was partially accomplished through keys and locks. When a door is locked, only someone with a key can enter through the door, depending on how the lock is configured. Mechanical locks and keys do not allow restriction of the key holder to specific times or dates. Mechanical locks and keys do not provide records of the key used on any specific door, and the keys can be easily copied or transferred to an unauthorized person. When a mechanical key is lost or the key holder is no longer authorized to use the protected area, the locks must be re-keyed.[citation needed] Electronic access control uses computers to solve the limitations of mechanical locks and keys. A wide range of credentials can be used to replace mechanical keys. The electronic access control system grants access based on the credential presented. When access is granted, the door is unlocked for a predetermined time and the transaction is recorded. When access is refused, the door remains locked and the attempted access is recorded. The system will also monitor the door and alarm if the door is forced open or held open too long after being unlocked
  • Credential
  • Access control system operation
  • The above description illustrates a single factor transaction. Credentials can be passed around, thus subverting the access control list. For example, Alice has access rights to the server room, but Bob does not. Alice either gives Bob her credential, or Bob takes it; he now has access to the server room. To prevent this, two-factor authentication can be used. In a two factor transaction, the presented credential and a second factor are needed for access to be granted; another factor can be a PIN, a second credential, operator intervention, or a biometric input
  • There are three types (factors) of authenticating information:[2] something the user knows, e.g. a password, pass-phrase or PIN something the user has, such as smart card or a key fob something the user is, such as fingerprint, verified by biometric measurement
  • Passwords are a common means of verifying a user's identity before access is given to information systems. In addition, a fourth factor of authentication is now recognized: someone you know, whereby another person who knows you can provide a human element of authentication in situations where systems have been set up to allow for such scenarios
  • When a credential is presented to a reader, the reader sends the credential’s information, usually a number, to a control panel, a highly reliable processor. The control panel compares the credential's number to an access control list, grants or denies the presented request, and sends a transaction log to a database. When access is denied based on the access control list, the door remains locked.
  • A credential is a physical/tangible object, a piece of knowledge, or a facet of a person's physical being, that enables an individual access to a given physical facility or computer-based information system. Typically, credentials can be something a person knows (such as a number or PIN), something they have (such as an access badge), something they are (such as a biometric feature) or some combination of these items. This is known as multi-factor authentication. The typical credential is an access card or key-fob, and newer software can also turn users' smartphones into access devices.
  • An access control point, which can be a door, turnstile, parking gate, elevator, or other physical barrier, where granting access can be electronically controlled. Typically, the access point is a door. An electronic access control door can contain several elements. At its most basic, there is a stand-alone electric lock. The lock is unlocked by an operator with a switch. To automate this, operator intervention is replaced by a reader. The reader could be a keypad where a code is entered, it could be a card reader, or it could be a biometric reader. Readers do not usually make an access decision, but send a card number to an access control panel that verifies the number against an access list
  • monitor the door position
  • Generally only entry is controlled, and exit is uncontrolled. In cases where exit is also controlled, a second reader is used on the opposite side of the door. In cases where exit is not controlled, free exit, a device called a request-to-exit (REX) is used. Request-to-exit devices can be a push-button or a motion detector. When the button is pushed, or the motion detector detects motion at the door, the door alarm is temporarily ignored while the door is opened. Exiting a door without having to electrically unlock the door is called mechanical free egress. This is an important safety feature. In cases where the lock must be electrically unlocked on exit, the request-to-exit device also unlocks the doo
  • Access control topology
  • Access control decisions are made by comparing the credential to an access control list. This look-up can be done by a host or server, by an access control panel, or by a reader. The development of access control systems has seen a steady push of the look-up out from a central host to the edge of the system, or the reader. The predominant topology circa 2009 is hub and spoke with a control panel as the hub, and the readers as the spokes. The look-up and control functions are by the control panel. The spokes communicate through a serial connection; usually RS-485. Some manufactures are pushing the decision making to the edge by placing a controller at the door. The controllers are IP enabled, and connect to a host and database using standard networks
  • Access control readers may be classified by the functions they are able to perform
  • and forward it to a control panel.
  • Basic (non-intelligent) readers: simply read
  • Semi-intelligent readers: have all inputs and outputs necessary to control door hardware (lock, door contact, exit button), but do not make any access decisions. When a user presents a card or enters a PIN, the reader sends information to the main controller, and waits for its response. If the connection to the main controller is interrupted, such readers stop working, or function in a degraded mode. Usually semi-intelligent readers are connected to a control panel via an RS-485 bus.
  • Intelligent readers: have all inputs and outputs necessary to control door hardware; they also have memory and processing power necessary to make access decisions independently. Like semi-intelligent readers, they are connected to a control panel via an RS-485 bus. The control panel sends configuration updates, and retrieves events from the readers.
  • Systems with IP readers usually do not have traditional control panels, and readers communicate directly to a PC that acts as a host
  • a built in webservice to make it user friendly
  • Some readers may have additional features such as an LCD and function buttons for data collection purposes (i.e. clock-in/clock-out events for attendance reports), camera/speaker/microphone for intercom, and smart card read/write support
Tiberius Brastaviceanu

Open Source Completely 3-D Printable Centrifuge - Appropedia, the sustainability wiki - 0 views

www.appropedia.org/etely_3-D_Printable_Centrifuge

open science open hardware OSH catalog

shared by Tiberius Brastaviceanu on 10 Oct 23 - No Cached
  • Tiberius Brastaviceanu on 10 Oct 23
     
    "Centrifuges are commonly required devices in medical diagnostics facilities as well as scientific laboratories. Although there are commercial and open source centrifuges, the costs of the former and the required electricity to operate the latter limit accessibility in resource-constrained settings. There is a need for low-cost, human-powered, verified, and reliable lab-scale centrifuges. This study provides the designs for a low-cost 100% 3-D printed centrifuge, which can be fabricated on any low-cost RepRap-class (self-replicating rapid prototyper) fused filament fabrication (FFF)- or fused particle fabrication (FPF)-based 3-D printer. In addition, validation procedures are provided using a web camera and free and open source software. This paper provides the complete open source plans, including instructions for the fabrication and operation of a hand-powered centrifuge. This study successfully tested and validated the instrument, which can be operated anywhere in the world with no electricity inputs, obtaining a radial velocity of over 1750 rpm and over 50 N of relative centrifugal force. Using commercial filament, the instrument costs about U.S. $25, which is less than half of all commercially available systems. However, the costs can be dropped further using recycled plastics on open source systems for over 99% savings. The results are discussed in the context of resource-constrained medical and scientific facilities."
Francois Bergeron

MyoStretcher - 0 views

www.ionoptix.com/...myostretcher

tools company cardiac myocytes scientific instruments

shared by Francois Bergeron on 24 Oct 12 - No Cached
  • IonOptix is proud to announce the release of the MyoStretcher, our new cardiomyocyte force measurement system.  Facilitated by the arrival of IonOptix MyoTak, our bio-compatible cell adhesive, we've developed the MyoStretcher with a focus on simplicity, ease-of-use and reliability.  The MyoStretcher includes all of the necessary components to stretch as well as record force in isolated myocytes.  In addition to the sensitive force transducer, motorized micro-manipulators and all component fittings, we also offer an optional piezo-electric translator for programmable stretching and a kit to facilitate attachment of glass rods to the MyoStretcher arms.
Tiberius Brastaviceanu

What is an ontology and why we need it - 1 views

protege.stanford.edu/...ntology101-noy-mcguinness.html

protege ontologies infrastructure tutorial

shared by Tiberius Brastaviceanu on 29 Jul 12 - Cached
  • an ontology designer makes these decisions based on the structural properties of a class.
  • an ontology is a formal explicit description of concepts in a domain of discourse (classes (sometimes called concepts)), properties of each concept describing various features and attributes of the concept (slots (sometimes called roles or properties)), and restrictions on slots (facets (sometimes called role restrictions)). An ontology together with a set of individual instances of classes constitutes a knowledge base. In reality, there is a fine line where the ontology ends and the knowledge base begins.
  • Classes describe concepts in the domain
  • ...16 more annotations...
  • A class can have subclasses that represent concepts that are more specific than the superclass.
  • Here we discuss general issues to consider and offer one possible process for developing an ontology. We describe an iterative approach to ontology development: we start with a rough first pass at the ontology. We then revise and refine the evolving ontology and fill in the details. Along the way, we discuss the modeling decisions that a designer needs to make, as well as the pros, cons, and implications of different solutions.
  • In practical terms, developing an ontology includes: �         defining classes in the ontology, �         arranging the classes in a taxonomic (subclass–superclass) hierarchy, �         defining slots and describing allowed values for these slots, �         filling in the values for slots for instances.
  • We can then create a knowledge base by defining individual instances of these classes filling in specific slot value information and additional slot restrictions.
  • Slots describe properties of classes and instances:
  • some fundamental rules in ontology design
  • There is no one correct way to model a domain— there are always viable alternatives. The best solution almost always depends on the application that you have in mind and the extensions that you anticipate. 2)      Ontology development is necessarily an iterative process. 3)      Concepts in the ontology should be close to objects (physical or logical) and relationships in your domain of interest. These are most likely to be nouns (objects) or verbs (relationships) in sentences that describe your domain.
  • how detailed or general the ontology is going to be
  • what we are going to use the ontology for
  • concepts in the ontology must reflect this reality
  • We suggest starting the development of an ontology by defining its domain and scope. That is, answer several basic questions: �         What is the domain that the ontology will cover? �         For what  we are going to use the ontology? �         For what types of questions the information in the ontology should provide answers? �         Who will use and maintain the ontology?
  • plan to use
  • domain
  • If the people who will maintain the ontology describe the domain in a language that is different from the language of the ontology users, we may need to provide the mapping between the languages.
  • One of the ways to determine the scope of the ontology is to sketch a list of questions that a knowledge base based on the ontology should be able to answer, competency questions
  • These competency questions are just a sketch and do not need to be exhaustive.
Tiberius Brastaviceanu

Density Design | Fineo - 1 views

www.densitydesign.org/...fineo

design infographics Visualization tools Fineo

shared by Tiberius Brastaviceanu on 28 Sep 11 - No Cached
  • Tiberius Brastaviceanu on 18 Feb 13
     
    DensityDesign develops research projects in the domain of visual representation, stemming from a design perspective. Our research interests include theoretical and epistemological reflections on visualizations and analyses of their cognitive underpinnings, in addition to the development of large frameworks for data visualization and ad-hoc solutions for speculative narration. We adopt an open approach to visualization, working from visual storytelling to visual analytics. Design is, thus, treated more like a proper language than a tool. We use this language in practice to define a new-visual-epistemology.
Tiberius Brastaviceanu

Google Apps Script - introduction - 0 views

code.google.com/...guide_events.html

google script apps Programming javascript tool tools infrastructure

shared by Tiberius Brastaviceanu on 03 May 11 - No Cached
  • script that you want to run every day at a specific time
  • script that should run after a user submits a data-collection form.
  • Google Apps Script provides simple event handlers and installable event handlers, which are easy ways for you to specify functions to run at a particular time or in response to an event.
  • ...39 more annotations...
  • let's consider the terminology we use for events
  • event triggers
  • triggers
  • in response
  • event handler
  • event
  • onInstall function
  • onOpen function.
  • onEdit function
  • the simple event handlers are restricted in what they are permitted to do:
  • The spreadsheet containing the script must be opened for editing
  • cannot determine the current user
  • cannot access any services that require authentication as that user
  • Calendar, Mail and Site are not anonymous and the simple event handlers cannot access those services.
  • can only modify the current spreadsheet. Access to other spreadsheets is forbidden.
  • see Understanding Permissions and Script Execution.
  • The onOpen function runs automatically when a user opens a spreadsheet.
  • add custom menu items to the spreadsheet's menu bar.
  • onEdit function runs automatically when any cell of the spreadsheet is edited.
  • record the last modified time in a comment on the cell that was edited.
  • The onInstall function is called when a script is installed from the Script Gallery.
  • setting up custom menus for the user.
  • the script can call onOpen from onInstall.
  • Installable event handlers are set on the Triggers menu within the Script Editor, and they're called triggers in this document.
  • When a specific time is reached
  • When a form is submitted
  • When a Spreadsheet is edited
  • When a Spreadsheet is opened.
  • They can potentially access all services available to the user who installed the handler.
  • are fully-capable scripts with none of the access limitations of simple event handlers
  • may not be able to determine which user triggered the event being handled
  • The spreadsheet containing the script does not have to be open for the event to be triggered and the script to run.
  • You can connect triggers to one or more functions in a script. Any function can have multiple triggers attached. In addition, you can add trigger attributes to a function to further refine how the trigger behaves.
  • When a script runs because of a trigger, the script runs using the identity of the person who installed the trigger, not the identity of the user whose action triggered the event. This is for security reasons.
  • Installing an event handler may prompt for authorization to access
  • An event is passed to every event handler as the argument (e). You can add attributes to the (e) argument that further define how the trigger works or that capture information about how the script was triggered.
  • an example of a function that sends email to a designated individual containing information captured by a Spreadsheet when a form is submitted.
  • With Google Apps, forms have the option to automatically record the submitter's username, and this is available to the script as e.namedValues["Username"]. Note: e.namedValues are only available for Google Apps domains and not for consumer Google accounts.
  • The available attributes for triggers are described in the following tables.
  • Tiberius Brastaviceanu on 03 May 11
     
    script that you want to run every day at a specific time
Tiberius Brastaviceanu

Is Shame Necessary? | Conversation | Edge - 0 views

www.edge.org/...is-shame-necessary

shame collaboration cooperation paper theory

shared by Tiberius Brastaviceanu on 28 Oct 11 - No Cached
  • What is shame's purpose? Is shame still necessary?
  • Shame is what is supposed to occur after an individual fails to cooperate with the group.
  • Whereas guilt is evoked by an individual's standards, shame is the result of group standards. Therefore, shame, unlike guilt, is felt only in the context of other people.
  • ...53 more annotations...
  • Many animals use visual observations to decide whether to work with others.
  • humans are more cooperative when they sense they're being watched.
  • The feeling of being watched enhances cooperation, and so does the ability to watch others. To try to know what others are doing is a fundamental part of being human
  • Shame serves as a warning to adhere to group standards or be prepared for peer punishment. Many individualistic societies, however, have migrated away from peer punishment toward a third-party penal system
  • Shame has become less relevant in societies where taking the law into one's own hands is viewed as a breach of civility.
  • Many problems, like most concerning the environment, are group problems. Perhaps to solve these problems we need a group emotion. Maybe we need shame.
  • Guilt prevails in many social dilemmas
  • It is perhaps unsurprising that a set of tools has emerged to assuage this guilt
  • Guilt abounds in many situations where conservation is an issue.
  • The problem is that environmental guilt, though it may well lead to conspicuous ecoproducts, does not seem to elicit conspicuous results.
  • The positive effect of idealistic consumers does exist, but it is masked by the rising demand and numbers of other consumers.
  • Guilt is a valuable emotion, but it is felt by individuals and therefore motivates only individuals. Another drawback is that guilt is triggered by an existing value within an individual. If the value does not exist, there is no guilt and hence no action
  • Getting rid of shaming seems like a pretty good thing, especially in regulating individual behavior that does no harm to others. In eschewing public shaming, society has begun to rely more heavily on individual feelings of guilt to enhance cooperation.
  • five thousand years ago, there arose another tool: writing
  • Judges in various states issue shaming punishments,
  • shaming by the state conflicts with the law's obligation to protect citizens from insults to their dignity.
  • What if government is not involved in the shaming?
  • Is this a fair use of shaming? Is it effective?
  • Shaming might work to change behavior in these cases, but in a world of urgent, large-scale problems, changing individual behavior is insignificant
  • vertical agitation
  • Guilt cannot work at the institutional level, since it is evoked by individual scruples, which vary widely
  • But shame is not evoked by scruples alone; since it's a public sentiment, it also affects reputation, which is important to an institution.
  • corporate brand reputation outranked financial performance as the most important measure of success
  • shame and reputation interact
  • in our early evolution we could gauge cooperation only firsthand
  • Shaming, as noted, is unwelcome in regulating personal conduct that doesn't harm others. But what about shaming conduct that does harm others?
  • why we learned to speak.1
  • Language
  • The need to accommodate the increasing number of social connections and monitor one another could be
  • allowed for gossip, a vector of social information.
  • in cooperation games that allowed players to gossip about one another's performance, positive gossip resulted in higher cooperation.
  • Of even greater interest, gossip affected the players' perceptions of others even when they had access to firsthand information.
  • Human society today is so big that its dimensions have outgrown our brains.
  • What tool could help us gossip in a group this size?
  • We can use computers to simulate some of the intimacy of tribal life, but we need humans to evoke the shame that leads to cooperation. The emergence of new tools— language, writing, the Internet—cannot completely replace the eyes. Face-to-face interactions, such as those outside Trader Joe's stores, are still the most impressive form of dissent.
  • what is stopping shame from catalyzing social change? I see three main drawbacks:
  • Today's world is rife with ephemeral, or "one-off," interactions.
  • Research shows, however, that if people know they will interact again, cooperation improves
  • Shame works better if the potential for future interaction is high
  • In a world of one-off interactions, we can try to compensate for anonymity with an image score,
  • which sends a signal to the group about an individual's or institution's degree of cooperation.
  • Today's world allows for amorphous identities
  • It's hard to keep track of who cooperates and who doesn't, especially if it's institutions you're monitoring
  • Shaming's biggest drawback is its insufficiency.
  • Some people have no shame
  • shame does not always encourage cooperation from players who are least cooperative
  • a certain fraction of a given population will always behave shamelessly
  • if the payoff is high enough
  • There was even speculation that publishing individual bankers' bonuses would lead to banker jealousy, not shame
  • shame is not enough to catalyze major social change
  • This is why punishment remains imperative.
  • Even if shaming were enough to bring the behavior of most people into line, governments need a system of punishment to protect the group from the least cooperative players.
  • Today we are faced with the additional challenge of balancing human interests and the interests of nonhuman life.
  • Tiberius Brastaviceanu on 28 Oct 11
     
    The role of non-rational mechanisms in convergence - social emotions like shame and guilt 
Kurt Laitner

Digital Reality | Edge.org - 0 views

edge.org/...il_gershenfeld-digital-reality

*neilgershenfeld fab labs IoT molecular computing nano star trek replicator

shared by Kurt Laitner on 17 Feb 15 - No Cached
  • When you snap the bricks together, you don't need a ruler to play Lego; the geometry comes from the parts
  • first attribute is metrology that comes from the parts
  • digitizing composites into little linked loops of carbon fiber instead of making giant pieces
  • ...75 more annotations...
  • In a 3D printer today, what you can make is limited by the size of the machine. The geometry is external
  • is the Lego tower is more accurate than the child because the constraint of assembling the bricks lets you detect and correct errors
  • That's the exponential scaling for working reliably with unreliable parts
  • Because the parts have a discrete state, it means in joining them you can detect and correct errors
  • detect and correct state to correct errors to get an exponential reduction in error, which gives you an exponential increase in complexity
  • The next one is you can join Lego bricks made out of dissimilar materials.
  • The last one is when you're done with Lego you don't put it in the trash; you take it apart and reuse it because there's state in the materials. In a forest there's no trash; you die and your parts get disassembled and you're made into new stuff. When you make a 3D print or laser cut, when you're done there's recycling attempts but there's no real notion of reusing the parts
  • The metrology coming from the parts, detecting and correcting errors, joining dissimilar materials, disconnecting, reusing the components
  • On the very smallest scale, the most exciting work on digital fabrication is the creation of life from scratch. The cell does everything we're talking about. We've had a great collaboration with the Venter Institute on microfluidic machinery to load designer genomes into cells. One step up from that we're developing tabletop chip fab instead of a billion dollar fab, using discrete assembly of blocks of electronic materials to build things like integrated circuits in a tabletop process
  • a child can make a Lego structure bigger than themself
  • There's a series of books by David Gingery on how to make a machine shop starting with charcoal and iron ore.
  • There are twenty amino acids. With those twenty amino acids you make the motors in the molecular muscles in my arm, you make the light sensors in my eye, you make my neural synapses. The way that works is the twenty amino acids don't encode light sensors, or motors. They’re very basic properties like hydrophobic or hydrophilic. With those twenty properties you can make you. In the same sense, digitizing fabrication in the deep sense means that with about twenty building blocks—conducting, insulating, semiconducting, magnetic, dielectric—you can assemble them to create modern technology
  • By discretizing those three parts we can make all those 500,000 resistors, and with a few more parts everything else.
  • Now, there's a casual sense, which means a computer controls something to make something, and then there's the deep sense, which is coding the materials. Intellectually, that difference is everything but now I'm going to explain why it doesn't matter.
  • Then in turn, the next surprise was they weren't there for research, they weren't there for theses, they wanted to make stuff. I taught additive, subtractive, 2D, 3D, form, function, circuits, programming, all of these skills, not to do the research but just using the existing machines today
  • What they were answering was the killer app for digital fabrication is personal fabrication, meaning, not making what you can buy at Walmart, it’s making what you can't buy in Walmart, making things for a market of one person
  • The minicomputer industry completely misread PCs
  • the Altair was life changing for people like me. It was the first computer you could own as an individual. But it was almost useless
  • It was hard to use but it brought the cost from a million dollars to 100,000 and the size from a warehouse down to a room. What that meant is a workgroup could have one. When a workgroup can have one it meant Ken Thompson and Dennis Ritchie at Bell Labs could invent UNIX—which all modern operating systems descend from—because they didn't have to get permission from a whole corporation to do it
  • At the PC stage what happened is graphics, storage, processing, IO, all of the subsystems got put in a box
  • To line that up with fabrication, MIT's 1952 NC Mill is similar to the million-dollar machines in my lab today. These are the mainframes of fab. You need a big organization to have them. The fab labs I'll tell you about are exactly analogous to the cost and complexity of minicomputers. The machines that make machines I'll tell you about are exactly analogous to the cost and complexity of the hobbyist computers. The research we're doing, which is leading up to the Star Trek Replicator, is what leads to the personal fabricator, which is the integrated unit that makes everything
  • conducting, resistive, insulating.
  • The fab lab is 2 tons, a $100,000 investment. It fills a few thousand square feet, 3D scanning and printing, precision machining, you can make circuit boards, molding and casting tooling, computer controlled cutting with a knife, with a laser, large format machining, composite layup, surface mount rework, sensors, actuators, embedded programming— technology to make technology.
  • Ten years you can just plot this doubling. Today, you can send a design to a fab lab and you need ten different machines to turn the data into something. Twenty years from now, all of that will be in one machine that fits in your pocket.
  • We've been living with this notion that making stuff is an illiberal art for commercial gain and it's not part of the means of expression. But, in fact, today, 3D printing, micromachining, and microcontroller programming are as expressive as painting paintings or writing sonnets but they're not means of expression from the Renaissance. We can finally fix that boundary between art and artisans
  • You don't go to a fab lab to get access to the machine; you go to the fab lab to make the machine.
  • Over the next maybe five years we'll be transitioning from buying machines to using machines to make machines. Self-reproducing machines
  • But they still have consumables like the motors, and they still cut or squirt. Then the interesting transition comes when we go from cutting or printing to assembling and disassembling, to moving to discretely assembled materials
  • because if anybody can make anything anywhere, it challenges everything
    • Kurt Laitner
      Kurt Laitner on 17 Feb 15
       
      great quote (replace challenges with changes for effect)
  • Now, the biggest surprise for me in this is I thought the research was hard. It's leading to how to make the Star Trek Replicator. The insight now is that's an exercise in embodied computation—computation in materials, programming their construction. Lots of work to come, but we know what to do
  • And that's when you do tabletop chip fab or make airplanes. That's when technical trash goes away because you can disassemble. 
  • irritated by the maker movement for the failure in mentoring
  • At something like a Maker Faire, there's hall after hall of repeated reinventions of bad 3D printers and there isn't an easy process to take people from easy to hard
  • We started a project out of desperation because we kept failing to succeed in working with existing schools, called the Fab Academy. Now, to understand how that works, MIT is based on scarcity. You assume books are scarce, so you have to go there for the library; you assume tools are scarce, so you have to go there for the machines; you assume people are scarce, so you have to go there to see them; and geography is scarce. It adds up to we can fit a few thousand people at a time. For those few thousand people it works really well. But the planet is a few billion people. We're off by six orders of magnitude. 
  • Next year we're starting a new class with George Church that we've called "How to Grow Almost Anything", which is using fab labs to make bio labs and then teach biotech in it. What we're doing is we're making a new global kind of university
  • Amusingly, I went to my friends at Educause about accrediting the Fab Academy and they said, "We love it. Where are you located?" And I said, "Yes" and they said, "No." Meaning, "We're all over the earth." And they said, "We have no mechanism. We're not allowed to do that. There's no notion of global accreditation."
  • Then they said something really helpful: "Pretend."
  • Once you have a basic set of tools, you can make all the rest of the tools
  • The way the Fab Academy works, in computing terms, it's like the Internet. Students have peers in workgroups, with mentors, surrounded by machines in labs locally. Then we connect them globally by video and content sharing and all of that. It's an educational network. There are these critical masses of groups locally and then we connect them globally
  • You still have Microsoft or IBM now but, with all respect to colleagues there, arguably that's the least interesting part of software
  • To understand the economic and social implications, look at software and look at music to understand what's happening now for fabrication
  • There's a core set of skills a place like MIT can do but it alone doesn't scale to a billion people. This is taking the social engineering—the character of MIT—but now doing it on this global scale.
  • Mainframes didn't go away but what opened up is all these tiers of software development that weren't economically viable
  • If you look at music development, the most interesting stuff in music isn't the big labels, it's all the tiers of music that weren't viable before
  • You can make music for yourself, for one, ten, 100, 1,000, a million. If you look at the tracks on your device, music is now in tiers that weren't economically viable before. In that example it's a string of data and it becomes a sound. Now in digital fab, it's a string of data and it becomes a thing.
  • What is work? For the average person—not the people who write for Edge, but just an average person working—you leave home to go to a place you'd rather not be, doing a repetitive operation you'd rather not do, making something designed by somebody you don't know for somebody you'll never see, to get money to then go home and buy something. But what if you could skip that and just make the thing?
    • Kurt Laitner
      Kurt Laitner on 17 Feb 15
       
      !!!
  • It took about ten years for the dot com industry to realize pretty much across the board you don't directly sell the thing. You sell the benefits of the thing
  • 2016 it's in Shenzhen because they're pivoting from mass manufacturing to enabling personal fabrication. We've set Shenzhen as the goal in 2016 for Fab Lab 2.0, which is fab labs making fab labs
  • To rewind now, you can send something to Shenzhen and mass manufacture it. There's a more interesting thing you can do, which is you go to market by shipping data and you produce it on demand locally, and so you produce it all around the world.
  • But their point was a lot of printers producing beautiful pages slowly scales if all the pages are different
  • In the same sense it scales to fabricate globally by doing it locally, not by shipping the products but shipping the data.
  • It doesn't replace mass manufacturing but mass manufacturing becomes the least interesting stuff where everybody needs the same thing. Instead, what you open up is all these tiers that weren't viable before
  • There, they consider IKEA the enemy because IKEA defines your taste. Far away they make furniture and flat pack it and send it to a big box store. Great design sense in Barcelona, but 50 percent youth unemployment. A whole generation can't work. Limited jobs. But ships come in from the harbor, you buy stuff in a big box store. And then after a while, trucks go off to a trash dump. They describe it as products in, trash out. Ships come in with products, trash goes out
    • Kurt Laitner
      Kurt Laitner on 17 Feb 15
       
      worse actually.. the trash stays
  • The bits come and go, globally connected for knowledge, but the atoms stay in the city.
  • instead of working to get money to buy products made somewhere else, you can make them locally
    • Kurt Laitner
      Kurt Laitner on 17 Feb 15
       
      this may solve greece's problem, walk away from debt, you can't buy other people's (country's) stuff anymore, so make it all yourself
  • The biggest tool is a ShotBot 4'x8'x1' NC mill, and you can make beautiful furniture with it. That's what furniture shops use
  • Anything IKEA makes you can make in a fab lab
  • it means you can make many of the things you consume directly rather than this very odd remote economic loop
  • the most interesting part of the DIY phone projects is if you're making a do-it-yourself phone, you can also start to make the things that the phones talk to. You can start to build your own telco providers where the users provide the network rather than spending lots of money on AT&T or whoever
  • Traditional manufacturing is exactly replaying the script of the computer companies saying, "That's a toy," and it's shining a light to say this creates entirely new economic activity. The new jobs don't come back to the old factories. The ability to make stuff on demand is creating entirely new jobs
  • To keep playing that forward, when I was in Barcelona for the meeting of all these labs hosted by the city architect and the city, the mayor, Xavier Trias, pushed a button that started a forty-year countdown to self-sufficiency. Not protectionism
  • I need high-torque efficient motors with integrated lead screws at low cost, custom-produced on demand. All sorts of the building blocks that let us do what I'm doing currently rest on a global supply chain including China's manufacturing agility
  • The short-term answer is you can't get rid of them because we need them in the supply chain. But the long-term answer is Shenzhen sees the future isn't mass producing for everybody. That's a transitional stage to producing locally
  • My description of MIT's core competence is it's a safe place for strange people
  • The real thing ultimately that's driving the fab labs ... the vacuum we filled is a technical one. The means to make stuff. Nobody was providing that. But in turn, the spaces become magnets. Everybody talks about innovation or knowledge economy, but then most things that label that strangle it. The labs become vehicles for bright inventive people who don't fit locally. You can think about the culture of MIT but on this global scale
  • My allegiance isn't to any one border, it's to the brainpower of the planet and this is building the infrastructure to scale to that brainpower
  • If you zoom from transistors to microcode to object code to a program, they don't look like each other. But if we take this room and go from city, state, country, it's hierarchical but you preserve geometry
  • Computation violates geometry unlike most anything else we do
  • The reason that's so important for the digital fabrication piece is once we build molecular assemblers to build arbitrary systems, you don't want to then paste a few lines of code in it. You need to overlay computation with geometry. It's leading to this complete do-over of computer science
  • If you take digital fab, plus the real sense of Internet of Things—not the garbled sense—plus the real future of computing aligning hardware and software, it all adds up to this ability to program reality
  • I run a giant video infrastructure and I have collaborators all over the world that I see more than many of my colleagues at MIT because we're all too busy on campus. The next Silicon Valley is a network, it's not a place. Invention happens in these networks.
  • When Edwin Land was kicked out of Polaroid, he made the Rowland Institute, which was making an ideal research institute with the best facilities and the best people and they could do whatever they want. But almost nothing came from it because there was no turnover of the gene pool, there was no evolutionary pressure.  
  • the wrong way to do research, which is to believe there's a privileged set of people that know more than anybody else and to create a barrier that inhibits communication from the inside to the outside
  • you need evolutionary pressure, you need traffic, you need to be forced to deal with people you don't think you need to encounter, and you need to recognize that to be disruptive it helps to know what people know
  • For me the hardest thing isn't the research. That's humming along nicely. It's that we're finding we have to build a completely new kind of social order and that social entrepreneurship—figuring out how you live, learn, work, play—is hard and there's a very small set of people who can do that kind of organizational creation.
    • Kurt Laitner
      Kurt Laitner on 17 Feb 15
       
      our challenge in the OVN space
  • Kurt Laitner on 17 Feb 15
     
    what is heavy is local, what is light is global, and increasingly manufacturing is being recreated along this principle
Tiberius Brastaviceanu

The New Normal in Funding University Science | Issues in Science and Technology - 1 views

issues.org/...-in-funding-university-science

open science paper

shared by Tiberius Brastaviceanu on 07 Aug 14 - No Cached
  • Government funding for academic research will remain limited, and competition for grants will remain high. Broad adjustments will be needed
  • he sequester simply makes acute a chronic condition that has been getting worse for years.
  • the federal budget sequester
  • ...72 more annotations...
  • systemic problems that arise from the R&D funding system and incentive structure that the federal government put in place after World War II
  • Researchers across the country encounter increasingly fierce competition for money.
  • unding rates in many National Institutes of Health (NIH) and National Science Foundation (NSF) programs are now at historical lows, declining from more than 30% before 2001 to 20% or even less in 2011
  • even the most prominent scientists will find it difficult to maintain funding for their laboratories, and young scientists seeking their first grant may become so overwhelmed that individuals of great promise will be driven from the field
  • anxiety and frustration
  • The growth of the scientific enterprise on university campuses during the past 60 years is not sustainable and has now reached a tipping point at which old models no longer work
  • Origins of the crisis
  • ederal funding agencies must work with universities to ensure that new models of funding do not stymie the progress of science in the United States
  • The demand for research money greatly exceeds the supply
  • the demand for research funding has gone up
  • The deeper sources of the problem lie in the incentive structure of the modern research university, the aspirations of scientists trained by those universities, and the aspirations of less research-intensive universities and colleges across the nation
  • competitive grants system
  • if a university wants to attract a significant amount of sponsored research money, it needs doctoral programs in the relevant fields and faculty members who are dedicated to both winning grants and training students
  • The production of science and engineering doctorates has grown apace
  • Even though not all doctorate recipients become university faculty, the size of the science and engineering faculty at U.S. universities has grown substantially
  • proposal pressure goes up
  • These strategies make sense for any individual university, but will fail collectively unless federal funding for R&D grows robustly enough to keep up with demand.
  • At the very time that universities were enjoying rapidly growing budgets, and creating modes of operation that assumed such largess was the new normal, Price warned that it would all soon come to a halt
  • the human and financial resources invested in science had been increasing much faster than the populations and economies of those regions
  • growth in the scientific enterprise would have to slow down at some point, growing no more than the population or the economy.
  • Dead-end solutions
  • studies sounded an alarm about the potential decline in U.S. global leadership in science and technology and the grave implications of that decline for economic growth and national security
  • Although we are not opposed to increasing federal funding for research, we are not optimistic that it will happen at anywhere near the rate the Academies seek, nor do we think it will have a large impact on funding rates
  • universities should not expect any radical increases in domestic R&D budgets, and most likely not in defense R&D budgets either, unless the discretionary budgets themselves grow rapidly. Those budgets are under pressure from political groups that want to shrink government spending and from the growth of spending in mandatory programs
  • The basic point is that the growth of the economy will drive increases in federal R&D spending, and any attempt to provide rapid or sustained increases beyond that growth will require taking money from other programs.
  • The demand for research money cannot grow faster than the economy forever and the growth curve for research money flattened out long ago.
  • Path out of crisis
  • The goal cannot be to convince the government to invest a higher proportion of its discretionary spending in research
  • Getting more is not in the cards, and some observers think the scientific community will be lucky to keep what it has
  • The potential to take advantage of the infrastructure and talent on university campuses may be a win-win situation for businesses and institutions of higher education.
  • Why should universities and colleges continue to support scientific research, knowing that the financial benefits are diminishing?
  • esearch culture
  • attract good students and faculty as well as raise their prestige
  • mission to expand the boundaries of human knowledge
  • faculty members are committed to their scholarship and will press on with their research programs even when external dollars are scarce
  • training
  • take place in
  • research laboratories
  • it is critical to have active research laboratories, not only in elite public and private research institutions, but in non-flagship public universities, a diverse set of private universities, and four-year colleges
  • How then do increasingly beleaguered institutions of higher education support the research efforts of the faculty, given the reality that federal grants are going to be few and far between for the majority of faculty members? What are the practical steps institutions can take?
  • change the current model of providing large startup packages when a faculty member is hired and then leaving it up to the faculty member to obtain funding for the remainder of his or her career
  • universities invest less in new faculty members and spread their internal research dollars across faculty members at all stages of their careers, from early to late.
    • Tiberius Brastaviceanu
      Tiberius Brastaviceanu on 07 Aug 14
       
      Sharing of resources, see SENSORICA's NRP
  • national conversation about changes in startup packages and by careful consultations with prospective faculty hires about long-term support of their research efforts
  • Many prospective hires may find smaller startup packages palatable, if they can be convinced that the smaller packages are coupled with an institutional commitment to ongoing research support and more reasonable expectations about winning grants.
  • Smaller startup packages mean that in many situations, new faculty members will not be able to establish a functioning stand-alone laboratory. Thus, space and equipment will need to be shared to a greater extent than has been true in the past.
  • construction of open laboratory spaces and the strategic development of well-equipped research centers capable of efficiently servicing the needs of an array of researchers
  • phaseout of the individual laboratory
  • enhanced opportunities for communication and networking among faculty members and their students
  • Collaborative proposals and the assembly of research teams that focus on more complex problems can arise relatively naturally as interactions among researchers are facilitated by proximity and the absence of walls between laboratories.
  • An increased emphasis on team research
  • investments in the research enterprise
  • can be directed at projects that have good buy-in from the faculty
  • learn how to work both as part of a team and independently
  • Involvement in multiple projects should be encouraged
  • The more likely trajectory of a junior faculty member will evolve from contributing team member to increasing leadership responsibilities to team leader
  • nternal evaluations of contributions and potential will become more important in tenure and promotion decisions.
    • Tiberius Brastaviceanu
      Tiberius Brastaviceanu on 07 Aug 14
       
      Need value accounting system
  • relationships with foundations, donors, state agencies, and private business will become increasingly important in the funding game
  • The opportunities to form partnerships with business are especially intriguing
    • Tiberius Brastaviceanu
      Tiberius Brastaviceanu on 07 Aug 14
       
      The problem is to change the model and go open source, because IP stifles other processes that might benefit Universities!!!
  • Further complicating university collaborations with business is that past examples of such partnerships have not always been easy or free of controversy.
  • some faculty members worried about firms dictating the research priorities of the university, pulling graduate students into proprietary research (which could limit what they could publish), and generally tugging the relevant faculty in multiple directions.
  • developed rules and guidelines to control them
  • University faculty and businesspeople often do not understand each other’s cultures, needs, and constraints, and such gaps can lead to more mundane problems in university/industry relations, not least of which are organizational demands and institutional cultures
    • Tiberius Brastaviceanu
      Tiberius Brastaviceanu on 07 Aug 14
       
      Needs for mechanisms to govern, coordinate, structure an ecosystem -See SENSORICA's Open Alliance model
  • n addition to funding for research, universities can receive indirect benefits from such relationships. High-profile partnerships with businesses will underline the important role that universities can play in the economic development of a region.
  • Universities have to see firms as more than just deep pockets, and firms need to see universities as more than sources of cheap skilled labor.
  • foundations or other philanthropy
  • We do not believe that research proposed and supervised by individual principal investigators will disappear anytime soon. It is a research model that has proven to be remarkably successful and enduring
  • However, we believe that the most vibrant scientific communities on university and college campuses, and the ones most likely to thrive in the new reality of funding for the sciences, will be those that encourage the formation of research teams and are nimble with regard to funding sources, even as they leave room for traditional avenues of funding and research.
Tiberius Brastaviceanu

Beyond Blockchain: Simple Scalable Cryptocurrencies - The World of Deep Wealth - Medium - 0 views

medium.com/...-cryptocurrencies-1eb7aebac6ae

blockchainaccess_project paper Holochain Arthur Brock

shared by Tiberius Brastaviceanu on 01 Jun 16 - No Cached
  • I clarify the core elements of cryptocurrency and outline a different approach to designing such currencies rooted in biomimicry
  • This post outlines a completely different strategy for implementing cryptocurrencies with completely distributed chains
  • Rather than trying to make one global, anonymous, digital cash
  • ...95 more annotations...
  • we are interested in the resilience that comes from building a rich ecosystem of interoperable currencies
  • What are the core elements of a modern cryptocurrency?
  • Digital
  • Holdings are electronic and only exist and operate by virtue of a community’s agreement about how to interpret digital bits according to rules about operation and accounting of the currency.
  • Trustless
  • don’t have to trust a 3rd party central authority
  • Decentralized
  • Specifically, access, issuance, transaction accounting, rules & policies, should be collectively visible, known, and held.
  • Cryptographic
  • This cryptographic structure is used to enable a variety of people to host the data without being able to alter it.
  • Identity
  • there must be a way to associate these bits with some kind of account, wallet, owner, or agent who can use them
  • Other things that many take for granted in blockchains may not be core but subject to decisions in design and implementation, so they can vary between implementations
  • It does not have to be stored in a synchronized global ledger
  • does not have to be money. It may be a reputation currency, or data used for identity, or naming, etc
  • Its units do not have to be cryptographic tokens or coins
  • It does not have to protect the anonymity of users, although it may
  • if you think currency is only money, and that money must be artificially scarce
  • Then you must tackle the problem of always tracking which coins exist, and which have been spent. That is one approach — the one blockchain takes.
  • You might optimize for anonymity if you think of cryptocurrency as a tool to escape governments, regulations, and taxes.
  • if you want to establish and manage membership in new kinds of commons, then identity and accountability for actions may turn out to be necessary ingredients instead of anonymity.
  • In the case of the MetaCurrency Project, we are trying to support many use cases by building tools to enable a rich ecosystem of communities and current-sees (many are non-monetary) to enhance collective intelligence at all scales.
  • Managing consensus about a shared reality is a central challenge at the heart of all distributed computing solutions.
  • If we want to democratize money by having cryptocurrencies become a significant and viable means of transacting on a daily basis, I believe we need fundamentally more scalable approaches that don’t require expensive, dedicated hardware just to participate.
  • We should not need system wide consensus for two people to do a transaction in a cryptocurrency
  • Blockchain is about managing a consensus about what was “said.” Ceptr is about distributing a consensus about how to “speak.”
  • how nature gets the job done in massively scalable systems which require coordination and consistency
  • Replicate the same processes across all nodes
  • Empower every node with full agency
  • Hold this transformed state locally and reliably
  • Establish protocols for interaction
  • Each speaker of a language carries the processes to understand sentences they hear, and generate sentences they need
  • we certainly don’t carry some kind of global ledger of everything that’s ever been said, or require consensus about what has been said
  • Language IS a communication protocol we learn by emulating the processes of usage.
  • Dictionaries try to catch up when the usage
  • there is certainly no global ledger with consensus about the state of trillions of cells. Yet, from a single zygote’s copy of DNA, our cells coordinate in a highly decentralized manner, on scales of trillions, and without the latency or bottlenecks of central control.
  • Imagine something along the lines of a Java Virtual Machine connected to a distributed version of Github
  • Every time this JVM runs a program it confirms the hash of the code it is about to execute with the hash signed into the code repository by its developers
  • This allows each node that intends to be honest to be sure that they’re running the same processes as everyone else. So when two parties want to do a transaction, and each can have confidence their own code, and the results that your code produces
  • Then you treat it as authoritative and commit it to your local cryptographically self-validating data store
  • Allowing each node to treat itself as a full authority to process transactions (or interactions via shared protocols) is exactly how you empower each node with full agency. Each node runs its copy of the signed program/processes on its own virtual machine, taking the transaction request combined with the transaction chains of the parties to the transaction. Each node can confirm their counterparty’s integrity by replaying their transactions to produce their current state, while confirming signatures and integrity of the chain
  • If both nodes are in an appropriate state which allows the current transaction, then they countersign the transaction and append to their respective chains. When you encounter a corrupted or dishonest node (as evidenced by a breach of integrity of their chain — passing through an invalid state, broken signatures, or broken links), your node can reject the transaction you were starting to process. Countersigning allows consensus at the appropriate scale of the decision (two people transacting in this case) to lock data into a tamper-proof state so it can be stored in as many parallel chains as you need.
  • When your node appends a mutually validated and signed transaction to its chain, it has updated its local state and is able to represent the integrity of its data locally. As long as each transaction (link in the chain) has valid linkages and countersignatures, we can know that it hasn’t been tampered with.
  • If you can reliably embody the state of the node in the node itself using Intrinsic Data Integrity, then all nodes can interact in parallel, independent of other interactions to maximize scalability and simultaneous processing. Either the node has the credits or it doesn’t. I don’t have to refer to a global ledger to find out, the state of the node is in the countersigned, tamper-proof chain.
  • Just like any meaningful communication, a protocol needs to be established to make sure that a transaction carries all the information needed for each node to run the processes and produce a new signed and chained state. This could be debits or credits to an account which modify the balance, or recoding courses and grades to a transcript which modify a Grade Point Average, or ratings and feedback contributing to a reputation score, and so on.
  • By distributing process at the foundation, and leveraging Intrinsic Data Integrity, our approach results in massive improvements in throughput (from parallel simultaneous independent processing), speed, latency, efficiency, and cost of hardware.
  • You also don’t need to incent people to hold their own record — they already want it.
  • Another noteworthy observation about humans, cells, and atoms, is that each has a general “container” that gets configured to a specific use.
  • Likewise, the Receptors we’ve built are a general purpose framework which can load code for different distributed applications. These Receptors are a lightweight processing container for the Ceptr Virtual Machine Host
  • Ceptr enables a developer to focus on the rules and transactions for their use case instead of building a whole framework for distributed applications.
  • how units in a currency are issued
  • Most people think that money is just money, but there are literally hundreds of decisions you can make in designing a currency to target particular needs, niches, communities or patterns of flow.
  • Blockchain cryptocurrencies are fiat currencies. They create tokens or coins from nothing
  • These coins are just “spoken into being”
  • the challenging task of
  • ensure there is no counterfeiting or double-spending
  • Blockchain cryptocurrencies are fiat currencies
  • These coins are just “spoken into being”
  • the challenging task of tracking all the coins that exist to ensure there is no counterfeiting or double-spending
  • You wouldn’t need to manage consensus about whether a cryptocoin is spent, if your system created accounts which have normal balances based on summing their transactions.
  • In a mutual credit system, units of currency are issued when a participant extends credit to another user in a standard spending transaction
  • Alice pays Bob 20 credits for a haircut. Alice’s account now has -20, and Bob’s has +20.
  • Alice spent credits she didn’t have! True
  • Managing the currency supply in a mutual credit system is about managing credit limits — how far people can spend into a negative balance
  • Notice the net number units in the system remains zero
  • One elegant approach to managing mutual credit limits is to set them based on actual demand.
  • concerns about manufacturing fake accounts to game credit limits (Sybil Attacks)
  • keep in mind there can be different classes of accounts. Easy to create, anonymous accounts may get NO credit limit
  • What if I alter my code to give myself an unlimited credit limit, then spend as much as I want? As soon as you pass the credit limit encoded in the shared agreements, the next person you transact with will discover you’re in an invalid state and refuse the transaction.
  • If two people collude to commit an illegal transaction by both hacking their code to allow a normally invalid state, the same still pattern still holds. The next person they try to transact with using untampered code will detect the problem and decline to transact.
  • Most modern community currency systems have been implemented as mutual credit,
  • Hawala is a network of merchants and businessmen, which has been operating since the middle ages, performing money transfers on an honor system and typically settling balances through merchandise instead of transferring money
  • Let’s look at building a minimum viable cryptocurrency with the hawala network as our use case
  • To minimize key management infrastructure, each hawaladar’s public key is their address or identity on the network. To join the network you get a copy of the software from another hawaladar, generate your public and private keys, and complete your personal profile (name, location, contact info, etc.). You call, fax, or email at least 10 hawaladars who know you, and give them your IP address and ask them to vouch for you.
  • Once 10 other hawaladars have vouched for you, you can start doing other transactions because the protocol encoded in every node will reject a transaction chain that doesn’t start with at least 10 vouches
  • seeding your information with those other peers so you can be found by the rest of the network.
  • As described in the Mutual Credit section, at the time of transaction each party audits the counterparty’s transaction chain.
  • Our hawala crypto-clearinghouse protocol has two categories of transactions: some used for accounting and others for routing. Accounting transactions change balances. Routing transactions maintain network integrity by recording information about hawaladar
  • Accounting Transactions create signed data that changes account balances and contains these fields:
  • The final hash of all of the above fields is used as a unique transaction ID and is what each of party signs with their private keys. Signing indicates a party has agreed to the terms of the transaction. Only transactions signed by both parties are considered valid. Nodes can verify signatures by confirming that decryption of the signature using the public key yields a result which matches the transaction ID.
  • Routing Transactions sign data that changes the peers list and contain these fields:
  • As with accounting transactions, the hash of the above fields is used as the transaction’s unique key and the basis for the cryptographic signature of both counterparties.
  • Remember, instead of making changes to account balances, routing transactions change a node’s local list of peers for finding each other and processing.
  • a distributed network of mutual trust
  • operates across national boundaries
  • everyone already keeps and trusts their own separate records
  • Hawaladars are not anonymous
  • “double-spending”
  • It would be possible for someone to hack the code on their node to “forget” their most recent transaction (drop the head of their chain), and go back to their previous version of the chain before that transaction. Then they could append a new transaction, drop it, and append again.
  • After both parties have signed the agreed upon transaction, each party submits the transaction to separate notaries. Notaries are a special class of participant who validate transactions (auditing each chain, ensuring nobody passes through an invalid state), and then they sign an outer envelope which includes the signatures of the two parties. Notaries agree to run high-availability servers which collectively manage a Distributed Hash Table (DHT) servicing requests for transaction information. As their incentive for providing this infrastructure, notaries get a small transaction fee.
  • This approach introduces a few more steps and delays to the transaction process, but because it operates on independent parallel chains, it is still orders of magnitude more efficient and decentralized than reaching consensus on entries in a global ledger
  • millions of simultaneous transactions could be getting processed by other parties and notaries with no bottlenecks.
  • There are other solutions to prevent nodes from dropping the head of their transaction chain, but the approach of having notaries serve out a DHT solves a number of common objections to completely distributed accounting. Having access to reliable lookups in a DHT provides a similar big picture view that you get from a global ledger. For example, you may want a way to look up transactions even when the parties to that transaction are offline, or to be able to see the net system balance at a particular moment in time, or identify patterns of activity in the larger system without having to collect data from everyone individually.
  • By leveraging Intrinsic Data Integrity to run numerous parallel tamper-proof chains you can enable nodes to do various P2P transactions which don’t actually require group consensus. Mutual credit is a great way to implement cryptocurrencies to run in this peered manner. Basic PKI with a DHT is enough additional infrastructure to address main vulnerabilities. You can optimize your solution architecture by reserving reserve consensus work for tasks which need to guarantee uniqueness or actually involve large scale agreement by humans or automated contracts.
  • It is not only possible, but far more scalable to build cryptocurrencies without a global ledger consensus approach or cryptographic tokens.
  • Tiberius Brastaviceanu on 01 Jun 16
     
    Article written by Arthur Brook, founder of Metacurrency project and of Ceptr.
Tiberius Brastaviceanu

Key (lock) - Wikipedia, the free encyclopedia - 0 views

en.wikipedia.org/Key_(lock)

blockchainaccess_project paper access

shared by Tiberius Brastaviceanu on 09 Jun 16 - No Cached
  • Key systems
  • Individually keyed system (KD)[edit] With an individually keyed system, each cylinder can be opened by its unique key
  • Keyed alike (KA)[edit] This system allows for a number of cylinders to be operated by the same key. It is ideally suited to residential and commercial applications such as front and back doors.
  • ...10 more annotations...
  • Common entrance suite / Maison keying (CES)[edit] This system is widely used in apartments, office blocks and hotels. Each apartment (for example) has its own individual key which will not open the doors to any other apartments, but will open common entrance doors and communal service areas. It is often combined with a master-keyed system in which the key is kept by the landlord.
  • Master keyed (MK)
  • A master key operates a set of several locks. Usually, there is nothing special about the key itself, but rather the locks into which it will fit.
  • A practical attack exists to create a working master key for an entire system given only access to a single master-keyed lock, its associated change key, a supply of appropriate key blanks, and the ability to cut new keys. This is described in Cryptology and Physical Security: Rights Amplification in Master-Keyed Mechanical Locks.[36] However, for systems with many levels of master keys, it may be necessary to collect information from locks in different "subsystems" in order to deduce the master key. Locksmiths may also determine cuts for a replacement master key, when given several different key examples from a given system.
  • Control key
  • A control key is a special key used in removable core locking systems. The control key enables a user, who has very little skill, to remove from the core, with a specific combination, and replace it with a core that has a different combination.
  • Do not duplicate key
  • A "do not duplicate" key (or DND key, for short) is one that has been stamped "do not duplicate", "duplication prohibited
  • Restricted key
  • A restricted keyblank has a keyway for which a manufacturer has set up a restricted level of sales and distribution. Restricted keys are often protected by patent, which prohibits other manufacturers from making unauthorized productions of the key blank. In many cases, customers must provide proof of ID before a locksmith will cut additional keys using restricted blanks. Some companies, such as Medeco High Security Locks, have keyways that are restricted to having keys cut in the factory only. This is done to ensure the highest amount of security. These days, many restricted keys have special in-laid features, such as magnets, different types of metal, or even small computer chips to prevent duplication.
Francois Bergeron

All's Not Fair in Science and Publishing | The Scientist Magazine® - 0 views

www.the-scientist.com/?articles.view/articleNo/32287/title/All-s-Not-Fair-in-Science-and-Publishing/

open science paper

shared by Francois Bergeron on 02 Jan 13 - No Cached
  • My takeaway lesson was that the safest strategy was to divulge my results only after they were accepted for publication. And I’m sure I’m not the only one who feels this way. Science is too often a cutthroat venture, with publications as the currency for measuring one’s success. But with everyone keeping their findings secret until they have been approved by the peer-review process, aren’t we slowing the course of scientific discovery?
  • Scientists have failed to establish clear mores for crediting discoveries
  • Many believe that false attribution is actually increasing in frequency, likely motivated by the steady decrease in grant-funding rates.
  • ...2 more annotations...
  • Open Network
  • If scientific administrators aspire to accelerate innovation by encouraging team science, they must address this issue. Our university system should reward scientists who are honest and fair in their dealings with fellow investigators.  Specific protocols for guiding research and managing disagreements must be designed. Accurate laboratory records should reflect appropriate credit, and websites sponsored by international scientific organizations should be similarly designed to display accurate attribution of preliminary scientific discoveries. In addition, journals could post final drafts of papers before publication, allowing anonymous comments during a probationary period. If a substantive objection arises, the journal should require revisions or even reject the paper.
mayssamd

P2P Accounting for Planetary Survival - P2P Foundation - 0 views

wiki.p2pfoundation.net/ounting_for_Planetary_Survival

IoPA Book

shared by mayssamd on 20 Dec 22 - No Cached
  • mayssamd on 22 Dec 22
     
    Book containing relevant information relating to P2P accounting systems in additions to several case studies
Tiberius Brastaviceanu

BeagleBone Black ID: 1278 - $45.00 : Adafruit Industries, Unique & fun DIY electronics ... - 2 views

www.adafruit.com/1278

test

shared by Tiberius Brastaviceanu on 18 Jun 13 - No Cached
    • Tiberius Brastaviceanu
      Tiberius Brastaviceanu on 18 Jun 13
       
      Ronan bla bla bla
  • If you liked the BeagleBone, you will love the next gen BeagleBone Black! With a blistering 1GHz processor, 512MB onboard DDR3 RAM, built in 2GB storage with pre-installed Linux operating system (no microSD card required!), and best of all, the addition of a MicroHDMI connector for audio/video output. This is a ultra-powered embedded computer that can fit in a mint tin. Note: As of June 4, 2013, 1pm ET Adafruit is shipping Rev A5B.
  • n on supported accessories as we test them for compatibility. For now we suggest picking up a 5V 2A power supply and a micro-HDMI cable. If you want to use it 'head-less', a USB console cable is suggested as the 'Black does not have an onboard USB-to-Serial converter
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