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Francois Bergeron

Refined Myograph Systems for Mice and Rats, Lab Refined Myograph Systems - 0 views

  • The  pre-calibrated amplifier eliminates the need to calibrate with weights.
  • The system includes base, vertical support, bath support, micromanipulator block, micro- manipulator handle, muscle  supports rods, 1 pr/feet for rings, 25 μm and 100 μm Stainless Steel (3 m), 1 pr/hooks, 20 clips for strips, single myograph  bath and the TRN001 transducer.
  • Applications:• Pharmacological Effects• Receptors• Vaso-Mechanics• Pathology• Tissue Biopsies• GI Motility• Respiratory Airway Mechanics• Reproductive Physiology• Intracellular Ions with Fluorescence• Electrophysiological Measurements
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  • Basic Myograph for rings and strips 1 $7,385
Francois Bergeron

World Precision Instruments - Welcome! - 0 views

shared by Francois Bergeron on 14 Jun 11 - Cached
  • You can measure force in a single muscle cell!
Francois Bergeron

DMT Pressure Myography - 0 views

    • Francois Bergeron
       
      potential application for the Mosquito ?
  • The Pressure myograph systems are used to measure the physiological function and properties of small arteries, veins and other vessels.
  • Pathology Hypertension Atherosclerosis Diabetes Ischemia, heart disease and heart failure Tumors and angiogenesis Heart and lung diseases
Tiberius Brastaviceanu

Optical strain gauge - Google Patents - 0 views

  •  
    Far from what we have. This is about a moving object with a grating on it and a laser beam diffracting on it and detecting changes in the freq of res.  
Francois Bergeron

Physics News Graphics: Measuring Bond Rupture Forces with the Atomic Force Microscope - 0 views

  •  
    600 piconewton
Tiberius Brastaviceanu

Blood pressure (BP) measurements with fiber optic pressure sensor. Systolic blood pressure in mouse, intravascular blood pressure, intracranial pressure (ICP) in rat and intracranial pressure during trauma.Samba Sensors. Ultra-miniature Ultra-small Pressu - 3 views

  •  
    Another pressure sensor similar to the one FISO sells. Uses a membrane to sent the light back. 
  •  
    this swedish company started to manufacture engine compression control sensors for Volvo cars...
Francois Bergeron

Accelerometer and devices using the same - Patent # 6649905 - PatentGenius - 1 views

  • The forces involved in hitting a baseball are enormous. Estimates place them as high as 100 g. Not only must the instrument be able to measure them accurately in the first place but it must also be able to survive these extreme forces. Further,the instrument must be sufficiently miniaturized to be able to fit within a bore hole in the bat without fatally diminishing its strength. Preexisting accelerometers known to the present inventor fail on all scores. Solid state accelerometers have poorsignal to noise ratios and a relatively low dynamic range. Further, they have a long recovery time after a large impact.
Tiberius Brastaviceanu

Is Shame Necessary? | Conversation | Edge - 0 views

  • 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.
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  • 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.
  •  
    The role of non-rational mechanisms in convergence - social emotions like shame and guilt 
Francois Bergeron

Taskworld: Improving how the world collaborates-one task at a time™ - 2 views

  • A task management platform that measures performance and improves execution
Tiberius Brastaviceanu

Horizon 2020 - European Commission - 0 views

  • Latest news and events Register and come to the METRIC Final Conference! Event date: 19/03/2015 Brussels, Belgium The objective of the Final Conference is to present key findings on regional Transport Innovation Frameworks, measuring and explaining the performance of regional innovation frameworks, meta-analysis of main principles and typology for regional innovation, regional strategy plan and recommendations. Read more
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      hello group
    • Tiberius Brastaviceanu
       
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Tiberius Brastaviceanu

Why Great Innovations Fail: It's All in the Ecosystem - 0 views

  • “It is no longer enough to manage your innovation. Now you must manage your innovation ecosystem,”
  • example
  • Michelin developed a revolutionary new kind of tire with sensors and an internal hard wheel that could run almost perfectly for 125 miles after a puncture.
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  • Yet by 2007 the product was such a failure that Michelin had to abandon it.
  • The company hadn’t confronted the entire ecosystem the tire would rely on
  • conversion costs
  • expensive new equipment
  • legal challenges
  • Mastery of the ecosystem is the great strength that made Apple the supreme success story of our time,
  • The iPod
  • a beginning ecosystem that Jobs enlarged by introducing the iTunes Music Store.
  • the ecosystem further by opening up the Mac-only device to PC users.
  • In a world where mobile phone makers sold their devices to operators to sell to consumers, Jobs had such a powerful ecosystem that he could get operators to compete to partner with him: “And here was Apple, offering not just exclusive access to the most talked-about phone in history, but also exclusive access to Apple consumers—the most desirable customer segment imaginable
  • How do you take the measure of the ecosystem that your innovation will need to be part of and rely on? How do you not miss the blind spots that can lurk almost anywhere?
  • three main steps to take.
  • There are terrible pitfalls in the usual progression from prototype to pilot to rollout. It relies perilously on getting everything right from the very start. Often a far wiser and safer approach can be what Adner calls a “minimum viable footprint (MVF) rollout followed by a staged expansion.” In other words, start with a complete ecosystem, but a limited one.
Tiberius Brastaviceanu

Access control - Wikipedia, the free encyclopedia - 0 views

  • 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.
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  • 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
Kurt Laitner

Crisis of Value Theory - P2P Foundation - 0 views

  • accumulation of knowledge assets
  • a new class has arisen which controls the vectors of information
  • In terms of knowledge creation, a vast new information commons is being created, which is increasingly out of the control of cognitive capitalism.
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  • But notice that to do this, the system had to change, the core logic was no longer the same.
  • The emergence of the peer model of production, based on the non-rivalrous nature and virtually non-existent marginal cost of reproduction of digital information, and coupled with the increasing unenforceability of “intellectual property” laws, means that capital is incapable of realizing returns on ownership in the cognitive realm.
  • capital is becoming an a posteriori intervention in the realization of innovation, rather than a condition for its occurrence
  • 1) The creation of non-monetary value is exponential 2) The monetization of such value is linear
  • What this announces is a crisis of value, most such value is ‘beyond measure’, but also essentially a crisis of accumulation of capital.
  • more and more positive externalizations are created from the social field
  • “the core logic of the emerging experience economy, operating as it does in the world of non-rival exchange, is unlikely to have capitalism as its core logic.”
  • This takes the form both of “intellectual property” law, as well as direct subsidies from the taxpayer to the corporate economy
  • crisis of realization under state capitalism to capital’s growing dependence on the state to capture value from social production and redistribute it to private corporate owners
  • The state capitalist system will reach a point at which, thanks to the collapse of the portion of value comprised of rents on artificial property, the base of taxable value is imploding at the very time big business most needs subsidies to stay afloat.
  • We live in a political economy that has it exactly backwards. We believe that our natural world is infinite, and therefore that we can have an economic system based on infinite growth. But since the material world is finite, it is based on pseudo-abundance. And then we believe that we should introduce artificial scarcities in the world of immaterial production, impeding the free flow of culture and social innovation, which is based on free cooperation, by creating the obstacle of permissions and intellectual property rents protected by the state. What we need instead is a political economy based on a true notion of scarcity in the material realm, and a realization of abundance in the immaterial realm.
  • Brains and bodies still need others to produce value, but the others they need are not necessarily provided by capital and its capacities to organize production.
  • The household and informal economies have been allowed to function to the extent that they bear reproduction costs that would otherwise have to be internalized in wages; but they have been suppressed (as in the Enclosures) when they threaten to increase in size and importance to the point of offering a basis for independence from wage labor. “
  • increasing untenability of property rights in the information realm
  • there is no more outside.
  • one of intensive development, to grow in the immaterial field, and this is basically what the experience economy means
  • Innovation is becoming social and diffuse, an emergent property of the networks
  • failure of artificial abundance
  • failure of artificial scarcity
  •  
    the passing of the capitalist age
Francois Bergeron

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

  • 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.
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  • 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.
Kurt Laitner

Smart Contracts - 0 views

  • Whether enforced by a government, or otherwise, the contract is the basic building block of a free market economy.
  • A smart contract is a set of promises, specified in digital form, including protocols within which the parties perform on the other promises.
  • The basic idea of smart contracts is that many kinds of contractual clauses (such as liens, bonding, delineation of property rights, etc.) can be embedded in the hardware and software we deal with, in such a way as to make breach of contract expensive (if desired, sometimes prohibitively so) for the breacher.
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  • A broad statement of the key idea of smart contracts, then, is to say that contracts should be embedded in the world.
  • And where the vending machine, like electronic mail, implements an asynchronous protocol between the vending company and the customer, some smart contracts entail multiple synchronous steps between two or more parties
  • POS (Point of Sale)
  • EDI (Electronic Data Interchange
  • SWIFT
  • allocation of public network bandwidth via automated auctions
  • Smart contracts reference that property in a dynamic, proactively enforced form, and provide much better observation and verification where proactive measures must fall short.
  • The mechanisms of the world should be structured in such a way as to make the contracts (a) robust against naive vandalism, and (b) robust against sophisticated, incentive compatible (rational) breach.
  • A third category, (c) sophisticated vandalism (where the vandals can and are willing to sacrifice substantial resources), for example a military attack by third parties, is of a special and difficult kind that doesn't often arise in typical contracting, so that we can place it in a separate category and ignore it here.
  • The threat of physical force is an obvious way to embed a contract in the world -- have a judicial system decide what physical steps are to be taken out by an enforcement agency (including arrest, confiscation of property, etc.) in response to a breach of contract
  • It is what I call a reactive form of security.
  • The need to invoke reactive security can be minimized, but not eliminated, by making contractual arrangements verifiable
  • Observation of a contract in progress, in order to detect the first sign of breach and minimize losses, also is a reactive form of security
  • A proactive form of security is a physical mechanism that makes breach expensive
  • From common law, economic theory, and contractual conditions often found in practice, we can distill four basic objectives of contract design
  • observability
  • The disciplines of auditing and investigation roughly correspond with verification of contract performance
  • verifiability
  • The field of accounting is, roughly speaking, primarily concerned with making contracts an organization is involved in more observable
  • privity
  • This is a generalization of the common law principle of contract privity, which states that third parties, other than the designated arbitrators and intermediaries, should have no say in the enforcement of a contract
  • The field of security (especially, for smart contracts, computer and network security), roughly corresponds to the goal of privity.
  • enforceability
  • Reputation, built-in incentives, "self-enforcing" protocols, and verifiability can all play a strong part in meeting the fourth objective
  • Smart contracts often involve trusted third parties, exemplified by an intermediary, who is involved in the performance, and an arbitrator, who is invoked to resolve disputes arising out of performance (or lack thereof)
  • In smart contract design we want to get the most out of intermediaries and arbitrators, while minimizing exposure to them
  • Legal barriers are the most severe cost of doing business across many jurisdictions. Smart contracts can cut through this Gordian knot of jurisdictions
  • Where smart contracts can increase privity, they can decrease vulnerability to capricious jurisdictions
  • Secret sharing
  • The field of Electronic Data Interchange (EDI), in which elements of traditional business transactions (invoices, receipts, etc.) are exchanged electronically, sometimes including encryption and digital signature capabilities, can be viewed as a primitive forerunner to smart contracts
  • One important task of smart contracts, that has been largely overlooked by traditional EDI, is critical to "the meeting of the minds" that is at the heart of a contract: communicating the semantics of the protocols to the parties involved
  • There is ample opportunity in smart contracts for "smart fine print": actions taken by the software hidden from a party to the transaction.
  • Thus, via hidden action of the software, the customer is giving away information they might consider valuable or confidential, but the contract has been drafted, and transaction has been designed, in such a way as to hide those important parts of that transaction from the customer.
  • To properly communicate transaction semantics, we need good visual metaphors for the elements of the contract. These would hide the details of the protocol without surrendering control over the knowledge and execution of contract terms
  • Protocols based on mathematics, called cryptographic protocols, tre the basic building blocks that implement the improved tradeoffs between observability, verifiability, privity, and enforceability in smart contracts
  • secret key cryptography,
  • Public key cryptography
  • digital signatures
  • blind signature
  • Where smart contracts can increase observability or verifiability, they can decrease dependence on these obscure local legal codes and enforcement traditions
  • zero-knowledge interactive proof
  • digital mix
  • Keys are not necessarily tied to identities, and the task of doing such binding turns out to be more difficult than at first glance.
  • All public key operation are are done inside an unreadable hardware board on a machine with a very narrow serial-line connection (ie, it carries only a simple single-use protocol with well-verified security) to a dedicated firewall. Such a board is available, for example, from Kryptor, and I believe Viacrypt may also have a PGP-compatable board. This is economical for central sites, but may be less practical for normal users. Besides better security, it has the added advantage that hardware speeds up the public key computations.
  • If Mallet's capability is to physically sieze the machine, a weaker form of key protection will suffice. The trick is to hold the keys in volatile memory.
  • The data is still vulnerable to a "rubber hose attack" where the owner is coerced into revealing the hidden keys. Protection against rubber hose attacks might require some form of Shamir secret sharing which splits the keys between diverse phgsical sites.
  • How does Alice know she has Bob's key? Who, indeed, can be the parties to a smart contract? Can they be defined just by their keys? Do we need biometrics (such as autographs, typed-in passwords, retina scans, etc.)?
  • The public key cryptography software package "Pretty Good Privacy" (PGP) uses a model called "the web of trust". Alice chooses introducers whom she trusts to properly identify the map between other people and their public keys. PGP takes it from there, automatically validating any other keys that have been signed by Alice's designated introducers.
  • 1) Does the key actually belong to whom it appears to belong? In other words, has it been certified with a trusted signature?
  • 2) Does it belong to an introducers, someone you can trust to certify other keys?
  • 3) Does the key belong to someone you can trust to introduce other introducers? PGP confuses this with criterion (2). It is not clear that any single person has enough judgement to properly undertake task (3), nor has a reasonable institution been proposed that will do so. This is one of the unsolved problems in smart contracts.
  • PGP also can be given trust ratings and programmed to compute a weighted score of validity-- for example, two marginally trusted signatures might be considered as credible as one fully trusted signature
  • Notaries Public Two different acts are often called "notarization". The first is simply where one swears to the truth of some affidavit before a notary or some other officer entitled to take oaths. This does not require the notary to know who the affiant is. The second act is when someone "acknowledges" before a notary that he has executed a document as ``his own act and deed.'' This second act requires the notary to know the person making the acknowledgment.
  • "Identity" is hardly the only thing we might want map to a key. After all, physical keys we use for our house, car, etc. are not necessarily tied to our identity -- we can loan them to trusted friends and relatives, make copies of them, etc. Indeed, in cyberspace we might create "virtual personae" to reflect such multi-person relationships, or in contrast to reflect different parts of our personality that we do not want others to link. Here is a possible classification scheme for virtual personae, pedagogically presented:
  • A nym is an identifier that links only a small amount of related information about a person, usually that information deemed by the nym holder to be relevant to a particular organization or community
  • A nym may gain reputation within its community.
  • With Chaumian credentials, a nym can take advantage of the positive credentials of the holder's other nyms, as provably linked by the is-a-person credential
  • A true name is an identifier that links many different kinds of information about an person, such as a full birth name or social security number
  • As in magick, knowing a true name can confer tremendous power to one's enemies
  • A persona is any perstient pattern of behavior, along with consistently grouped information such as key(s), name(s), network address(es), writing style, and services provided
  • A reputable name is a nym or true name that has a good reputation, usually because it carries many positive credentials, has a good credit rating, or is otherwise highly regarded
  • Reputable names can be difficult to transfer between parties, because reputation assumes persistence of behavior, but such transfer can sometimes occur (for example, the sale of brand names between companies).
  • Blind signatures can be used to construct digital bearer instruments, objects identified by a unique key, and issued, cleared, and redeemed by a clearing agent.
  • The clearing agent prevents multiple clearing of particular objects, but can be prevented from linking particular objects one or both of the clearing nyms who transferred that object
  • These instruments come in an "online" variety, cleared during every transfer, and thus both verifiable and observable, and an "offline" variety, which can be transfered without being cleared, but is only verifiable when finally cleared, by revealing any the clearing nym of any intermediate holder who transfered the object multiple times (a breach of contract).
  • To implement a full transaction of payment for services, we need more than just the digital cash protocol; we need a protocol that guarantees that service will be rendered if payment is made, and vice versa
  • A credential is a claim made by one party about another. A positive credential is one the second party would prefer to reveal, such as a degree from a prestigious school, while that party would prefer not to reveal a negative credential such as a bad credit rating.
  • A Chaumian credential is a cryptographic protocol for proving one possesses claims made about onself by other nyms, without revealing linkages between those nyms. It's based around the is-a-person credential the true name credential, used to prove the linkage of otherwise unlinkable nyms, and to prevent the transfer of nyms between parties.
  • Another form of credential is bearer credential, a digital bearer instrument where the object is a credential. Here the second party in the claim refers to any bearer -- the claim is tied only to the reputable name of issuing organization, not to the nym or true name of the party holding the credential.
  • Smart Property We can extend the concept of smart contracts to property. Smart property might be created by embedding smart contracts in physical objects. These embedded protocols would automatically give control of the keys for operating the property to the party who rightfully owns that property, based on the terms of the contract. For example, a car might be rendered inoperable unless the proper challenge-response protocol is completed with its rightful owner, preventing theft. If a loan was taken out to buy that car, and the owner failed to make payments, the smart contract could automatically invoke a lien, which returns control of the car keys to the bank. This "smart lien" might be much cheaper and more effective than a repo man. Also needed is a protocol to provably remove the lien when the loan has been paid off, as well as hardship and operational exceptions. For example, it would be rude to revoke operation of the car while it's doing 75 down the freeway.
  • Smart property is software or physical devices with the desired characteristics of ownership embedded into them; for example devices that can be rendered of far less value to parties who lack possesion of a key, as demonstrated via a zero knowledge interactive proof
  • One method of implementing smart property is thru operation necessary data (OND): data necessary to the operation of smart property.
  • A smart lien is the sharing of a smart property between parties, usually two parties called the owner and the lienholder.
  • Many parties, especially new entrants, may lack this reputation capital, and will thus need to be able to share their property with the bank via secure liens
  • What about extending the concept of contract to cover agreement to a prearranged set of tort laws? These tort laws would be defined by contracts between private arbitration and enforcement agencies, while customers would have a choice of jurisdictions in this system of free-market "governments".
  • If these privately practiced law organizations (PPLs for short) bear ultimate responsibility for the criminal activities of their customers, or need to insure lack of defection or future payments on the part of customers, they may in turn ask for liens against their customers, either in with contractual terms allowing arrest of customers under certain conditions
  • Other important areas of liability include consumer liability and property damage (including pollution). There need to mechanisms so that, for example, pollution damage to others' persons or property can be assessed, and liens should exist so that the polluter can be properly charged and the victims paid. Where pollution is quantifiable, as with SO2 emissions, markets can be set up to trade emission rights. The PPLs would have liens in place to monitor their customer's emissions and assess fees where emission rights have been exceeded.
Tiberius Brastaviceanu

Dependability in peer production - 1 views

measures that p2p networks undertake to increase dependability in material peer production activities.

IoPA economic level ecosystem level legal level tech level social level standard level undecided levelundecided level

started by Tiberius Brastaviceanu on 13 Mar 23 no follow-up yet
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