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πŸ”— Johns Hopkins Beast

πŸ”— Systems πŸ”— Robotics πŸ”— Systems/Cybernetics

The Johns Hopkins Beast was a mobile automaton, an early pre-robot, built in the 1960s at the Johns Hopkins University Applied Physics Laboratory. The machine had a rudimentary intelligence and the ability to survive on its own. As it wandered through the white halls of the laboratory, it would seek black wall outlets. When it found one it would plug in and recharge.

The robot was cybernetic. It did not use a computer. Its control circuitry consisted of dozens of transistors controlling analog voltages. It used photocell optics and sonar to navigate. The 2N404 transistors were used to create NOR logic gates that implemented the Boolean logic to tell it what to do when a specific sensor was activated. The 2N404 transistors were also used to create timing gates to tell it how long to do something. 2N1040 Power transistors were used to control the power to the motion treads, the boom, and the charging mechanism.

The original sensors in Mod I were physical touch only. The wall socket was detected by physical switches on the arm that followed the wall. Once detected, two electrical prongs were extended until they entered the wall socket and made the electrical connection to charge the vehicle. The stairway, doors, and pipes on the hall wall were also detected by physical switches and recognized by appropriate logic.

The sonar guidance system was developed for Mod I and improved for Mod II. It used two ultrasonic transducers to determine distance, location within the halls, and obstructions in its path. This provided "The Beast" with bat-like guidance. At this point, it could detect obstructions in the hallway, such as people in the hallway. Once an obstruction was detected, the Beast would slow down and then decide whether to stop or divert around the obstruction. It could also ultrasonically recognize the stairway and doorways to take appropriate action.

An optical guidance system was added to Mod II. This provided, among other capabilities, the ability to optically identify the black wall sockets that contrasted with the white wall.

The Hopkins Beast Autonomous Robot Mod II link below was written by Dr. Ronald McConnell, at that time a co-op student and one of the designers for Mod II.

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πŸ”— GΓΆdel's ontological proof

πŸ”— Philosophy πŸ”— Philosophy/Logic πŸ”— Philosophy/Contemporary philosophy πŸ”— Philosophy/Philosophy of religion πŸ”— Christianity πŸ”— Christianity/theology πŸ”— Military history/European military history

GΓΆdel's ontological proof is a formal argument by the mathematician Kurt GΓΆdel (1906–1978) for the existence of God. The argument is in a line of development that goes back to Anselm of Canterbury (1033–1109). St. Anselm's ontological argument, in its most succinct form, is as follows: "God, by definition, is that for which no greater can be conceived. God exists in the understanding. If God exists in the understanding, we could imagine Him to be greater by existing in reality. Therefore, God must exist." A more elaborate version was given by Gottfried Leibniz (1646–1716); this is the version that GΓΆdel studied and attempted to clarify with his ontological argument.

GΓΆdel left a fourteen-point outline of his philosophical beliefs in his papers. Points relevant to the ontological proof include

4. There are other worlds and rational beings of a different and higher kind.
5. The world in which we live is not the only one in which we shall live or have lived.
13. There is a scientific (exact) philosophy and theology, which deals with concepts of the highest abstractness; and this is also most highly fruitful for science.
14. Religions are, for the most part, badβ€”but religion is not.

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πŸ”— Cognitive Architecture

πŸ”— Cognitive science πŸ”— Robotics

A cognitive architecture refers to both a theory about the structure of the human mind and to a computational instantiation of such a theory used in the fields of artificial intelligence (AI) and computational cognitive science. One of the main goals of a cognitive architecture is to summarize the various results of cognitive psychology in a comprehensive computer model. However, the results need to be formalized so far as they can be the basis of a computer program. The formalized models can be used to further refine a comprehensive theory of cognition, and more immediately, as a commercially usable model. Successful cognitive architectures include ACT-R (Adaptive Control of Thought - Rational) and SOAR.

The Institute for Creative Technologies defines cognitive architecture as: "hypothesis about the fixed structures that provide a mind, whether in natural or artificial systems, and how they work together – in conjunction with knowledge and skills embodied within the architecture – to yield intelligent behavior in a diversity of complex environments."

πŸ”— Signal for Help

πŸ”— Crime πŸ”— COVID-19 πŸ”— Women's History

The Signal for Help (or the Violence at Home Signal for Help) is a single-handed gesture that can be used by an individual to alert others that they feel threatened and need help over a video call, or in-person. It was originally created as a tool to combat the rise in domestic violence cases around the world as a result of the self-isolation measures related to the COVID-19 pandemic.

The signal is performed by holding one hand up with the thumb tucked into the palm, then folding the four other fingers down, symbolically trapping the thumb in the rest of the fingers. It was intentionally designed as a single continuous hand movement, rather than a sign held in one position, that could be made easily visible.

The Signal for Help was first introduced in Canada by the Canadian Women's Foundation on April 14, 2020, and on April 28, 2020 in the United States by the Women's Funding Network (WFN). It received widespread praise from local, national, and international news organizations for helping provide a modern solution to the issue of a rise in domestic violence cases.

Addressing concerns that abusers may become aware of such a widespread online initiative, the Canadian Women's Foundation and other organizations clarified that this signal is not "something that's going to save the day," but rather a tool someone could use to get help.

Instructions for what to do if an individual sees the signal, and how to check-in safely, were also created.

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πŸ”— COMEFROM

πŸ”— Computing πŸ”— Computer science

In computer programming, COMEFROM (or COME FROM) is an obscure control flow structure used in some programming languages, originally as a joke. COMEFROM is roughly the opposite of GOTO in that it can take the execution state from any arbitrary point in code to a COMEFROM statement.

The point in code where the state transfer happens is usually given as a parameter to COMEFROM. Whether the transfer happens before or after the instruction at the specified transfer point depends on the language used. Depending on the language used, multiple COMEFROMs referencing the same departure point may be invalid, be non-deterministic, be executed in some sort of defined priority, or even induce parallel or otherwise concurrent execution as seen in Threaded Intercal.

A simple example of a "COMEFROM x" statement is a label x (which does not need to be physically located anywhere near its corresponding COMEFROM) that acts as a "trap door". When code execution reaches the label, control gets passed to the statement following the COMEFROM. This may also be conditional, passing control only if a condition is satisfied, analogous to a GOTO within an IF statement. The primary difference from GOTO is that GOTO only depends on the local structure of the code, while COMEFROM depends on the global structure – a GOTO transfers control when it reaches a line with a GOTO statement, while COMEFROM requires scanning the entire program or scope to see if any COMEFROM statements are in scope for the line, and then verifying if a condition is hit. The effect of this is primarily to make debugging (and understanding the control flow of the program) extremely difficult, since there is no indication near the line or label in question that control will mysteriously jump to another point of the program – one must study the entire program to see if any COMEFROM statements reference that line or label.

Debugger hooks can be used to implement a COMEFROM statement, as in the humorous Python goto module; see below. This also can be implemented with the gcc feature "asm goto" as used by the Linux kernel configuration option CONFIG_JUMP_LABEL. A no-op has its location stored, to be replaced by a jump to an executable fragment that at its end returns to the instruction after the no-op.

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πŸ”— Rhythm 0

πŸ”— Visual arts

Rhythm 0 was a six-hour work of performance art by Serbian artist Marina Abramović in Naples in 1974. The work involved Abramović standing still while the audience was invited to do to her whatever they wished, using one of 72 objects she had placed on a table. These included a rose, feather, perfume, honey, bread, grapes, wine, scissors, a scalpel, nails, a metal bar, a gun, and a bullet.

There were no separate stages. Abramović and the visitors stood in the same space, making it clear that the latter were part of the work. The purpose of the piece, she said, was to find out how far the public would go: "What is the public about and what are they going to do in this kind of situation?"

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πŸ”— Vulcan Salute (Handshake Alternative, U+1F596)

πŸ”— Popular Culture πŸ”— Star Trek

The Vulcan salutation is a hand gesture popularized by the 1960s television series Star Trek. It consists of a raised hand with the palm forward and the thumb extended, while the fingers are parted between the middle and ring finger.

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πŸ”— Duck Curve

πŸ”— Energy

In utility-scale electricity generation, the duck curve is a graph of power production over the course of a day that shows the timing imbalance between peak demand and renewable energy production. The term was coined in 2012 by the California Independent System Operator.

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πŸ”— Hybrid Insect Micro-Electro-Mechanical Systems (Hi-MEMS)

πŸ”— Technology πŸ”— Aviation πŸ”— Military history πŸ”— Military history/North American military history πŸ”— Military history/United States military history πŸ”— Military history/Military science, technology, and theory πŸ”— Aviation/aircraft

Hybrid Insect Micro-Electro-Mechanical Systems (HI-MEMS) is a project of DARPA, a unit of the United States Department of Defense. Created in 2006, the unit's goal is the creation of tightly coupled machine-insect interfaces by placing micro-mechanical systems inside the insects during the early stages of metamorphosis. After implantation, the "insect cyborgs" could be controlled by sending electrical impulses to their muscles. The primary application is surveillance. The project was created with the ultimate goal of delivering an insect within 5 meters of a target located 100 meters away from its starting point. In 2008, a team from the University of Michigan demonstrated a cyborg unicorn beetle at an academic conference in Tucson, Arizona. The beetle was able to take off and land, turn left or right, and demonstrate other flight behaviors. Researchers at Cornell University demonstrated the successful implantation of electronic probes into tobacco hornworms in the pupal stage.

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πŸ”— Java Card

πŸ”— Java

Java Card is a software technology that allows Java-based applications (applets) to be run securely on smart cards and more generally on similar secure small memory footprint deviceswhich are called β€œsecure elements” (SE). Today, a Secure Element is not limited to its smart cards and other removable cryptographic tokens form factors; embedded SEs soldered onto a device board and new security designs embedded into general purpose chips are also widely used. Java Card addresses this hardware fragmentation and specificities while retaining code portability brought forward by Java.

Java Card is the tiniest of Java platforms targeted for embedded devices. Java Card gives the user the ability to program the devices and make them application specific. It is widely used in different markets: wireless telecommunications within SIM cards and embedded SIM, payment within banking cards and NFC mobile payment and for identity cards, healthcare cards, and passports. Several IoT products like gateways are also using Java Card based products to secure communications with a cloud service for instance.

The first Java Card was introduced in 1996 by Schlumberger's card division which later merged with Gemplus to form Gemalto. Java Card products are based on the specifications by Sun Microsystems (later a subsidiary of Oracle Corporation). Many Java card products also rely on the GlobalPlatform specifications for the secure management of applications on the card (download, installation, personalization, deletion).

The main design goals of the Java Card technology are portability, security and backward compatibility.