thenyminute

Thermodynamics

2008-09-09T23:47:00.001-07:00

As all catalysts, enzymes do not alter the position of the chemical equilibrium of the reaction. Usually, in the presence of an enzyme, the reaction runs in the same direction as it would without the enzyme, just more quickly. However, in the absence of the enzyme, other possible uncatalyzed, "spontaneous" reactions might lead to different products, because in those conditions this different product is formed faster.

Furthermore, enzymes can couple two or more reactions, so that a thermodynamically favorable reaction can be used to "drive" a thermodynamically unfavorable one. For example, the hydrolysis of ATP is often used to drive other chemical reactions.

Enzymes catalyze the forward and backward reactions equally. They do not alter the equilibrium itself, but only the speed at which it is reached. For example, carbonic anhydrase catalyzes its reaction in either direction depending on the concentration of its reactants.
Nevertheless, if the equilibrium is greatly displaced in one direction, that is, in a very exergonic reaction, the reaction is effectively irreversible. Under these conditions the enzyme will, in fact, only catalyze the reaction in the thermodynamically allowed direction.

Nootropic

2008-08-25T23:16:00.000-07:00

Nootropics, popularly referred to as "smart drugs", "smart nutrients", "cognitive enhancers" and "brain enhancers", are a class of drugs that improve impaired human cognitive abilities (the functions and capacities of the brain). The term covers a broad range of substances including drugs, nutrients and herbs that have purported cognitive enhancing effects.

The word nootropic was coined in 1964 by the Romanian Dr. Corneliu E. Giurgea, derived from the Greek words noos, or "mind," and tropein meaning "to bend/turn". Typically, nootropics are alleged to work by altering the availability of the brain's supply of neurochemicals (neurotransmitters, enzymes, and hormones), by improving the brain's oxygen supply, or by stimulating nerve growth. However the efficacy of alleged nootropic substances in most cases has not been conclusively determined. This is complicated by the difficulty of defining and quantifying cognition and intelligence.

Assisted GPS

2008-08-21T22:43:00.000-07:00

Conventional GPS has difficulty providing reliable positions in poor signal conditions. For example when surrounded by tall buildings (as a result of multipath), or when the satellite signals are weakened by being indoors or under trees. Some newer receivers are better at handling these situations.

In addition, when first turned on in these conditions, some non-assisted GPS units may not be able to download the almanac and ephemeris information from the GPS satellites, rendering them unable to function until a clear signal can be received continuously for up to one minute.

An A-GPS receiver can address these problems in several ways, using an Assistance Server:

* The Assistance Server can locate the phone roughly by what cell site it is connected to on the cellular network.
* The Assistance Server has a good satellite signal, and lots of computation power, so it can compare fragmentary signals relayed to it by cell phones, with the satellite signal it receives directly, and then inform the cell phone or emergency services of the cell phone's position.
* It can supply orbital data for the GPS satellites to the cell phone, enabling the cell phone to lock to the satellites when it otherwise could not, and autonomously calculate its position.
* By having accurate, surveyed coordinates for the cell site towers, it can have better knowledge of ionospheric conditions and other errors affecting the GPS signal than the cell phone alone, enabling more precise calculation of position. (See also Wide Area Augmentation System)

Some A-GPS solutions require an active connection to a cell phone (or other data) network to function, in others it simply makes positioning faster and more accurate, but is not required.

As an additional benefit, it can reduce both the amount of CPU and programming required for a GPS Phone by offloading most of the work onto the assistance server. (This is not a large amount for a basic GPS – many early GPSs utilized Intel 80386-class 16MHz CPUs or similar hardware.)

High Sensitivity GPS is an allied technology that addresses some of the same issues in a way that does not require additional infrastructure. However, unlike some forms of A-GPS, high sensitivity GPS cannot provide instant fixes when the phone has been off for some time.

Double-checked locking

2008-08-11T22:19:00.000-07:00

In software engineering, double-checked locking is a software design pattern also known as "double-checked locking optimization". The pattern is designed to reduce the overhead of acquiring a lock by first testing the locking criterion (the 'lock hint') in an unsafe manner; only if that succeeds does the actual lock proceed.

The pattern, when implemented in some language/hardware combinations, can be unsafe. It can therefore sometimes be considered to be an anti-pattern.

It is typically used to reduce locking overhead when implementing "lazy initialization" in a multi-threaded environment, especially as part of the Singleton pattern. Lazy initialization avoids initializing a value until the first time it is accessed.

Implicit Web

2008-08-05T21:36:00.000-07:00

The Implicit Web is a concept coined in 2007 to denote web sites which specialize in the synthesis of personal information gleaned from the Internet into a single, coherent picture of user behavior. Implicit data may include clickstream information, media consumption habits, location tracking or any data generated without "explicit" input from a user. Presumed advantages of implicit data include accuracy, ease of input and comprehensiveness.

The term Implicit Web was popularized by the technology investors Josh Kopelman, Fred Wilson, and Brad Feld.

Google Earth Plus

2008-07-29T23:30:00.000-07:00

Google Earth can be upgraded to a Plus edition for a $20 annual subscription fee. Google Earth Plus is an individual-oriented paid subscription upgrade to Google Earth and adds the following features:

* GPS integration: read tracks and waypoints from a GPS device. A variety of third party applications have been created which provide this functionality using the basic version of Google Earth by generating KML or KMZ files based on user-specified or user-recorded waypoints. However, Google Earth Plus provides direct support for the Magellan and Garmin product lines, which together hold a large share of the GPS market. The Linux version of the Google Earth Plus application does not include any GPS functionality.
* Higher resolution printing.
* Customer support via email.
* Data importer: read address points from CSV files; limited to 100 points/addresses. A feature allowing path and polygon annotations, which can be exported to KML, was formerly only available to Plus users, but was made free in version 4.0.2416.
* Higher data download speeds

Network model

2008-07-21T21:54:00.000-07:00

The network model is a database model conceived as a flexible way of representing objects and their relationships. Its original inventor was Charles Bachman, and it was developed into a standard specification published in 1969 by the CODASYL Consortium. Where the hierarchical model structures data as a tree of records, with each record having one parent record and many children, the network model allows each record to have multiple parent and child records, forming a lattice structure.

Object database

2008-07-14T23:06:00.000-07:00

In an object database (also object oriented database), information is represented in the form of objects as used in object-oriented programming. When database capabilities are combined with object programming language capabilities, the result is an object database management system (ODBMS). An ODBMS makes database objects appear as programming language objects in one or more object programming languages. An ODBMS extends the programming language with transparently persistent data, concurrency control, data recovery, associative queries, and other capabilities.

Some object-oriented databases are designed to work well with object-oriented programming languages such as Python, Java, C#, Visual Basic .NET, C++ and Smalltalk. Others have their own programming languages. ODBMSs use exactly the same model as object-oriented programming languages.

Customer Data Integration

2008-07-08T00:09:00.000-07:00

Customer Data Integration (CDI) is the combination of the technology, processes and services needed to create and maintain an accurate, timely, complete and comprehensive representation of a customer across multiple channels, business lines, and enterprises typically where there are multiple sources of associated data in multiple application systems and databases.

What does that really mean? When you ask the average Joe or Jane on the street “What is customer data?” they usually answer "Name and address...maybe social security number?"

However, customer data is much more complex; for example, the number of fields that represent just a name can be anywhere from six to twelve or more (e.g., first name, last name, middle name, initials, nickname, maiden name, married name, professional title, academic title and suffix.) The address entries are almost as complex (e.g., primary address number, pre-directional (N, S, E, W,) street name, street suffix, post-directional, secondary identifier (building, suite, apt,) secondary number, city, state, ZIP, and ZIP+4(R))

MUC (Message Unlock Code)

2008-07-02T04:04:00.000-07:00

MUC (Message Unlock Code)used to initiate trust. If a message is sent to a new recipient, the system generates a random MUC. The sender communicates the MUC to the recipient by using another communication channel than email, e.g. personally, by phone or SMS for security reasons (Out-of-band). With the MUC the recipient gets access to the secure message and confidential documents and can download them. If the recipient has already been in contact with the sender through secure messaging and is enrolled, a MUC is no longer required.

EICAR test file

2008-06-23T23:26:00.000-07:00

The EICAR test file (official name: EICAR Standard Anti-Virus Test File) is a file, developed by the European Institute for Computer Antivirus Research, to test the response of computer antivirus (AV) programs. The rationale behind it is to allow people, companies, and AV programmers to test their software without having to use a real computer virus that could cause actual damage should the AV not respond correctly. EICAR likens the use of a live virus to test AV software to setting a fire in a trashcan to test a fire alarm, and promotes the EICAR test file as a safe alternative.

A compliant virus scanner, when detecting the file, will respond in exactly the same manner as if it found genuinely harmful code. Its use can be more versatile than straightforward detection - for example, a file containing the EICAR test string can be compressed or archived, and then the antivirus software can be run to see whether it can detect the test string in the compressed file.

BlackBerry

2008-06-16T23:14:00.000-07:00

BlackBerry uses wireless Mail User Agent devices and a BlackBerry Enterprise Server (BES) attached to a traditional e-mail system. The BES monitors the e-mail server, and when it sees new e-mail for a BlackBerry user, it retrieves (pulls) a copy and then pushes it to the BlackBerry handheld device over the wireless network.

BlackBerry became very popular, in part because it offers remote users "instant" e-mail experience; new e-mails appear on the device as soon as they arrive, without the need for any user intervention. The handheld becomes a mobile, dynamically updating, copy of the user's mailbox. As a result of the success of BlackBerry, other manufacturers have developed push e-mail systems for other handheld devices, such as Symbian based mobile phones.

Evolutionary robotics

2008-06-11T00:38:00.000-07:00

Evolutionary Robotics (ER) is a methodology that uses evolutionary computation to develop controllers for autonomous robots. Algorithms in ER frequently operate on populations of candidate controllers, initially selected from some distribution. This population is then repeatedly modified according to a fitness function. In the case of genetic algorithms (or "GAs"), a common method in evolutionary computation, the population of candidate controllers is repeatedly grown according to crossover, mutation and other GA operators and then culled according to the fitness function. The candidate controllers used in ER applications may be drawn from some subset of the set of artificial neural networks, although some applications (including SAMUEL, developed at the Naval Center for Applied Research in Artificial Intelligence) use collections of "IF THEN ELSE" rules as the constituent parts of an individual controller. It is theoretically possible to use any set of symbolic formulations of a control laws (sometimes called a policies in the machine learning community) as the space of possible candidate controllers. It is worth noting that artificial neural networks can also be used for robot learning outside of the context of evolutionary robotics. In particular, other forms of reinforcement learning can be used for learning robot controllers.

Robot kit

2008-06-02T23:00:00.000-07:00

A robot kit is a special construction kit for building robots, especially autonomous mobile robots.

Toy robot kits are also supplied by several companies. They are mostly made of plastics elements like Lego Mindstorms and the Robotis Bioloid, or aluminium elements like Lynxmotion's Servo Erector Set and the qfix kit.

The kits can consist of: structural elements, mechanical elements, motors (or other actuators), sensors and a controller board to control the inputs and outputs of the robot. In some cases, the kits can be available without electronics as well, to provide the user the opportunity to use his or her own.

Process psychology

2008-05-27T22:20:00.000-07:00

Process psychology exists to integrate process thought with the field of psychology broadly construed.It is a new field which emerges from the application of Alfred North Whitehead's process philosophy to psychology. It holds the promise of integrating mind-body-spirit in a rigorous and coherent framework.

A pioneering work in this field is Toward a Process Psychology: A Model of Integration from David E. Roy publiced in 2000. Drawing from the depths of gestalt psychology and process metaphysics, David Roy sheds light on perplexing psychological questions regarding symbolism, mind-body relationship, and spiritual dimensions of human life. The meta-theory that emerges sheds light on psychology and psychotherapy alike. Such a rethinking of psychological questions and categories is invaluable for continued exploration of the human psyche and quest for health.

Cybernetics

2008-05-19T22:28:00.000-07:00

Cybernetics is the interdisciplinary study of the structure of complex systems, especially communication processes, control mechanisms and feedback principles. Cybernetics is closely related to control theory and systems theory.

Example of cybernetic thinking. On the one hand a company is approached as a system in an environment. On the other hand cybernetic factory can be modeled as a control system.

Example of cybernetic thinking. On the one hand a company is approached as a system in an environment. On the other hand cybernetic factory can be modeled as a control system.

Contemporary cybernetics began as an interdisciplinary study connecting the fields of control systems, electrical network theory, mechanical engineering, logic modeling, evolutionary biology and neuroscience in the 1940s.

Other fields of study which have influenced or been influenced by cybernetics include game theory, system theory (a mathematical counterpart to cybernetics), psychology (especially neuropsychology, behavioral psychology, cognitive psychology), philosophy, and architecture.

FLOSS

2008-05-12T22:58:00.000-07:00

"FLOSS" was used in 2001 as a project acronym by Rishab Aiyer Ghosh as an acronym for Free/Libre/Open-Source Software. Later that year, the European Commission (EC) used the phrase when they funded a study on the topic.

Unlike "libre software", which aimed to solve the ambiguity problem, "FLOSS" aimed to avoid taking sides in the debate over whether it was better to say "free software" or to say "open-source software".

Proponents of the term point out that parts of the FLOSS acronym can be translated into other European languages, with for example the "F" representing free (English) or frei (German), and the "L" representing libre (Spanish or French), livre (Portuguese), or libero (Italian). However, this term is not often used in official, non-English, documents, since the words in these languages for "free as in freedom" do not have the ambiguity problem of English's "free".

Caecilius Metellus

2008-05-06T22:30:00.000-07:00

Pomponius Mela writes, and is copied by Pliny the Elder, that Quintus Caecilius Metellus Celer (died 59 BCE), proconsul in Gaul received "several Indians" (Indi) as a present from a Germanic king. The Indians were driven by a storm to the coasts of Germania (in tempestatem ex Indicis aequoribus).

Metellus Celer recalls the following: when he was proconsul in Gaul, he was given people from "India" by the king of the Sueves; upon requesting why they were in this land, he learnt that they were caught in a storm away from India, that they became castaways, and finally landed on the coast of Germany. They thus resisted the sea, but suffered from the cold for the rest of their travel, and that is the reason why they left.

It is unclear whether these castaways may have been people from India or Eastern Asia, or possibly American Indians. Edward Herbert Bunbury suggested that they were Finns. This account is open to some question, since Metellus Celer died just after his consulship, before he ever got to Gaul.

Public transport

2008-04-28T21:25:00.000-07:00

Public transport, public transportation, public transit or mass transit comprise all transport systems that transport members of the general public, usually charging set fares. While the above terms are generally taken to include rail and bus services, wider definitions might include scheduled airline services, ferries, taxicab services etc. A further restriction that is sometimes applied is that transit should occur in continuously shared vehicles, which would exclude taxis that are not shared-ride taxis.

The term public transport is preferred in the British Isles and most Commonwealth countries, whereas public transportation, public transit and mass transit are used most often in North America. term transit is less likely to include long-distance forms of public transportation, such as long-distance or commuter railroads, inter-city buses, or intercity railways.

The Bering Land Bridge

2008-04-21T22:27:00.000-07:00

The Bering Land Bridge, the Jesuit scholar José de Acosta suggested that the peoples of the Americas arrived via a now-submerged land bridge from Asia as primitive hunters, later settling into sedentary communities and cities. In Notes on the State of Virginia (1781), Thomas Jefferson theorized that the ancestors of Native Americans crossed the Bering Strait from Asia, a viewpoint that came to prevail in the 20th century, as carbon dating and molecular genetics began to shed light on the origins of native populations.

Between the 1950s and the 1980s, the Bering Land Bridge theory came to be viewed as proven beyond any doubt. Most archaeologists came to believe that the native cultures of the Americas had been isolated from the Old World after the closing of the Bering land route, when they were still in the hunter-gatherer stage and developed without any outside influences for the next 9,000 years until the time of Columbus. It was also believed at the time that trans-oceanic travel only became possible in the 15th century, after key advances in Old World shipbuilding and navigation. This belief is supported by the lack of substantial evidence of Old World influences on American civilizations.

Computer-aided software engineering

2008-04-14T21:16:00.000-07:00

Computer-aided software engineering (CASE) is the use of software tools to assist in the development and maintenance of software. Tools used to assist in this way are known as CASE Tools.

Some typical CASE tools are:

* Code generation tools

* Data modeling tools

* UML

* Refactoring tools

* QVT or Model transformation Tools

* Configuration management tools including revision control

All aspects of the software development lifecycle can be supported by software tools, and so the use of tools from across the spectrum can, arguably, be described as CASE; from project management software through tools for business and functional analysis, system design, code storage, compilers, translation tools, test software, and so on.

Durability (database systems)

2008-04-07T22:14:00.000-07:00

In database systems, durability is the ACID property that guarantees that transactions that are successfully committed will survive permanently and will not be undone by system failure.

For example, if a flight booking database system reports that a seat has successfully been booked, then the seat will remain booked even if the system crashes. Durability also guarantees that the system will not rollback the transaction because the seat was double-booked.

The only way a transaction can be undone after it has been committed is by a compensatory transaction.

Database normalization

2008-04-04T23:07:00.000-07:00

Database normalization, sometimes referred to as canonical synthesis, is a technique for designing relational database tables to minimize duplication of information and, in so doing, to safeguard the database against certain types of logical or structural problems, namely data anomalies. For example, when multiple instances of a given piece of information occur in a table, the possibility exists that these instances will not be kept consistent when the data within the table is updated, leading to a loss of data integrity. A table that is sufficiently normalized is less vulnerable to problems of this kind, because its structure reflects the basic assumptions for when multiple instances of the same information should be represented by a single instance only.

Hypertext Transfer Protocol (HTTP)

2008-03-24T22:09:00.001-07:00

HTTP is a request/response standard between a client and a server. A client is the end-user, the server is the web site. The client making an HTTP request - using a web browser, spider, or other end-user tool - is referred to as the user agent. The responding server - which stores or creates resources such as HTML files and images - is called the origin server. In between the user agent and origin server may be several intermediaries, such as proxies, gateways, and tunnels. HTTP is not constrained to using TCP/IP and its supporting layers, although this is its most popular application on the Internet. Indeed HTTP can be "implemented on top of any other protocol on the Internet, or on other networks. HTTP only presumes a reliable transport; any protocol that provides such guarantees can be used."

Electric car

2008-03-17T22:00:00.000-07:00

The electric car is a vehicle that utilizes chemical energy stored in rechargeable battery packs, and electric motors and motor controllers instead of an internal combustion engine (ICE).

Vehicles using both electric motors and ICEs (hybrid electric vehicles) are examples of hybrid vehicles, and are not considered pure electric vehicles (EVs) because they operate in a charge-sustaining mode. Hybrid vehicles with batteries that can be charged externally to displace some or all of their ICE power and gasoline fuel are called plug-in hybrid electric vehicles (PHEV), and are pure BEVs during their charge-depleting mode. Electric vehicles include automobiles, light trucks, and neighborhood electric vehicles.