omniomni/omni-engineering huggingface dataset:
Blue Meanies (Apple Computer). The Blue Meanies of Apple Computer was an engineering group primarily responsible for the architecture of System 7 during the early and mid 1990s.

The name references the evil characters of Pepperland in the movie Yellow Submarine, and originated with the Pink and Blue split in Apple's operating system planning. Pink was the further-out project that ultimately became Taligent, and Blue designated incremental improvements to the flagship System 7. "Meanies" describes the group's architectural role, which frequently entailed instructing or negating engineers in other groups.

Though the Meanies have sometimes been characterized as the "coders of System 7", the OS was by then sufficiently large that major subsystems such as QuickDraw and QuickTime were developed and maintained by specialized groups, and the Meanies primarily focused on orchestrating the components together.

The name appeared outside of Apple as an Easter egg starting in System 7.0.1, where the texts "Help! Help! We're being held prisoner in a system software factory!" and "The Blue Meanies:" were followed by a list of names. Subsequent releases were updated to track the comings and goings of people in the group.

The nickname became well known, because many of the Meanies were also the senior engineers interacting with developers at venues such as the Worldwide Developers Conference (especially on the Stump the Experts panel) and MacHack. This included Darin Adler and Lew Cirne.

References

Pogue, David, and Joseph Schorr. "Macintosh Secret: The Secret Message in the System File." Macworld Mac & Power Mac Secrets. Ed. Mary Bednarek. 2nd ed. San Mateo: IDG, 1994. 162. Print. Secrets.

External links
cupertino.de | Archive | Easter Eggs | Blue Meanies Messages
A fictional story, written by Greg Marriott, formerly of the Blue Meanies

Apple Inc. employees
Tweaking. Tweaking refers to fine-tuning or adjusting a complex system, usually an electronic device. Tweaks are any small modifications intended to improve a system.

In electronics, it is a synonym for "trimming." Analog circuit boards often have small potentiometers or other components on them that are used to calibrate or adjust the board as a service procedure: the small insulated screwdriver used to turn them is often called a "tweaker."

This use was echoed in the name of the product Tweek, a popular but controversial audio product during the 1980s, which was claimed to improve the electrical characteristics of audio switch contacts.

Hardware
Hardware tweaking is a process of modifying certain parts of a hardware such as changing the cables, cleaning the heads of a VCR with a branded cleaning fluid or oiling the moving parts of an engine with the best possible oil.

Computer hardware
Computer hardware tweaking is an extension of hardware tweaking, specifically geared towards the components of a PC. They include: changing voltage and clock rates of processing units, modifying RAM unit timing, improving cooling systems to reduce chance of overheating, etc.

Tweaks specifically designed to allow a processor to operate at a higher clock speed than normal are known as overclocking.

Modifications of computer systems not aimed at increasing performance, such as quieter fans, external controls, and decorations such as lights or windows, are known as modding.

Software
Software tweaking is the process of improving the performance of an application or the quality of its output. There can be two ways of accomplishing this: manually (that is, if one is familiar with programming; though it may be irrelevant if the source of the application is closed, and there are no built-in means to adjust its performance) or using another piece of software specialized for that purpose. Tweaking of this kind generally increases usability, in terms of personal configuration preferences, rather than objective performance of the system overall).

Some very precise applications need constant and thorough tweaking to stay up to date and deliver best possible results. One of the most obvious examples of such a fine tuning is LAME MP3 encoder, whose 3.9x branch is not only considered as the state-of-the-art MP3 encoder, but also continues to shape the boundaries of the MP3 codec and stay competitive with its successors.

See also
 Overclocking
 Modding
 TweakUI

References

External links
 Tweakguides.com Site with various Windows and PC Game tweak guides

Computer hardware tuning
Piney Orchard, Maryland. Piney Orchard is an unincorporated community within the Washington DC suburb of Odenton, Maryland, United States. Piney Orchard began as a Planned Unit Development, and was a project of the Constellation Real Estate Group, Inc., a wholly owned subsidiary of the Constellation Energy Group, which itself, is now owned by Exelon.

Construction of the community began in 1991, although groundbreaking for what was to become the Nature Preserve started in 1987, when Constellation Real Estate Group began the effort to restore wetlands in an area which had been mined for sand and gravel in the 1940s and 1950s.  Several mitigation projects, the term used for this restoration, followed in five phases to replace wetlands filled in by the development of the community, and included the building and enhancement of five large ponds and the planting of shrubs, trees, and grasses native to the area. The Army Corps of Engineers, which oversees such efforts, monitored the progress of the mitigation sites until 1995, when it was determined the efforts had been successful. In 1996, the Piney Orchard Nature Preserve was officially opened.

More than 3500 housing units have been built in Piney Orchard and approximately 8500 residents live there. Constellation turned over the day-to-day supervision of Piney Orchard to the homeowners of the community in 2005. The Piney Orchard Community Association, or "POCA" as it is known, arranges several community-wide social activities and collects annual fees from all homeowners to maintain the aesthetic qualities of the community.

Piney Orchard Ice Arena, located at the corner of Piney Orchard Parkway and Riverscape Drive, had been the practice site for the Washington Capitals hockey team until 2006, when they moved to their newly built practice facility, Kettler Capitals Iceplex in Arlington, Virginia.

Sub-divisions within Piney Orchard

 Autumn Crest
 Brookwood
 Burgundy Place
 Cedar Ridge - Active Adult Community
 Chapel Village
 Chestnut Gable
 Chestnut Point
 The Courts
 Emory Woods
 Fieldstone Farms Apartments
 Francis Station
 The Gatherings at Forest Glen - Active Adult Community
 The Groves
 Harvest Run
 Maple Ridge
 Nature's Trail
 Piney Station
 River Colony
 River's Edge
 River Run
 Riverscape Apartments
 Settler's View
 Station House
 Stone Crossing
 Streamview
 Summer's Run
 Summit Chase
 The Vineyards
 Westcourts
 Woodland Walk

External links
Piney Orchard Community Association

Unincorporated communities in Anne Arundel County, Maryland
Unincorporated communities in Maryland
Exelon
Odenton, Maryland
Maximus (BBS). Maximus is a bulletin board system, originally developed by Scott J. Dudley through his company, Lanius Corporation.  The software was first written and released for both MS-DOS and OS/2, with later versions supporting 32-bit Windows operating systems.  The MS-DOS version interfaced with the serial port (and thus the modem) through a FOSSIL driver.  Version 1.0 was released in 1990, with versions 2.0 and 3.01 following in 1991 and 1995.  The source code for Maximus and its companion utilities, such as Squish, was released under the GNU General Public License in 2002.  It has since been ported to run under Linux, and other Unix-like operating systems.

By default, Maximus provides a relatively basic interface for BBS callers rendered in either ANSI or ASCII, compared with other BBS software.  Menu layout is auto-generated and simply-drawn.  With some effort, however, it is very customisable, including a provision for a system operator to supply RIP graphics for users.  When BBS systems were popular, Maximus often appealed to system operators who wanted a system that appeared light-weight, but also to those who wanted great flexibility in their ability to customise their system's looks and behaviour.

Maximus configuration is entirely through editing text files, prior to running a compiler to convert the text files to binary configuration files.  Maximus has supported two independent programming languages for system operators to customise their BBS.  Both are compiled to Maximus-recognised byte-code before being used:

 The MECCA language is primarily display-oriented, providing basic tokens to indicate actions such as colour changes for text displayed to a user, and simple functionality for designing things such as menus that require user input, or writing certain information to files on disk to exchange information with BBS door programs.
 Since the release of version 3.0 of Maximus, in December 1995, the MEX language is a more structured, Turing-complete programming language, that borrows ideas from C, Pascal, BASIC, and a selection of similar languages.  MEX provides supports for functions, structures, arrays, strings, and several additional complex concepts.  Using MEX, system operators can write reasonably complex programs to run on their BBS and interact with users.


See also 
 Squish - the primary mail format used by Maximus, and Fidonet mail tossing application used to process it.
 List of BBS software

References

Further reading
 Review of version 1.02 in PC Magazine of Sep 10, 1991, p. 260 continues on p. 267

External links
 
 The Maximus Home Page (archive from 2009)

Bulletin board system software
DOS software
OS/2 software
VDL SB200. The VDL SB200 (originally the DAF SB200) is a  light-weight, low floor single decker bus chassis that was produced from 2001 to 2014 by VDL Bus & Coach (formerly DAF Bus International). It superseded the SB220.

It is originally designed for use by Arriva (VDL dealer in the United Kingdom) in order to save fuel over heavy-weight citybuses which are designed for Continental Europe where buses carry large numbers of standing passengers, whereas in the UK they do not.

The SB200 sold very well in VDL's home market, the Netherlands mainly using VDL Berkhof type Ambassador and VDL Citea LLE bodywork. They were operated by all large transport companies in the Netherlands, Connexxion (including Hermes), Veolia Transport and Arriva. Arriva also used SB200s with Wright Commander bodywork.

Of the 831 built for United Kingdom operators, Arriva purchased 704, Tellings-Golden Miller 30 and John Fishwick & Sons 23.

Initially the SB200 built for the UK was only available with Wright Commander bodywork, but from 2006 it was available with the Plaxton Centro or Wright Pulsar bodywork, the latter being succeeded in late 2009 by the facelifted Wright Pulsar 2.

One VDL SB200 was fitted with an MCV Evolution body in 2012 as a static demonstrator for Arriva Bus & Coach, it was sold in 2014 to Richards Brothers in Wales.

References

External links

SB 200 product guide VDL Bus & Coach

Bus chassis
Low-floor buses
SB200
Vehicles introduced in 2001
Optode. An optode or optrode is an optical sensor device that optically measures a specific substance usually with the aid of a chemical transducer.

Construction
An optode requires three components to function: a chemical that responds to an analyte, a polymer to immobilise the chemical transducer and instrumentation (optical fibre, light source, detector and other electronics). Optodes usually have the polymer matrix coated onto the tip of an optical fibre, but in the case of evanescent wave optodes the polymer is coated on a section of fibre that has been unsheathed.

Operation
Optodes can apply various optical measurement schemes such as reflection, absorption, evanescent wave, luminescence (fluorescence and phosphorescences), chemiluminescence, surface plasmon resonance. By far the most popular methodology is luminescence.

Luminescence in solution obeys the linear Stern–Volmer relationship. Fluorescence of a molecule is quenched by specific analytes, e.g., ruthenium complexes are quenched by oxygen.  When a fluorophore is immobilised within a polymer matrix myriad micro-environments are created. The micro-environments reflect varying diffusion co-efficients for the analyte. This leads to a non-linear relationship between the fluorescence and the quencher (analyte). This relationship is modelled in various ways, the most popular model is the two site model created by James Demas (University of Virginia).

The signal (fluorescence) to oxygen ratio is not linear, and an optode is most sensitive at low oxygen concentration, i.e., the sensitivity decreases as oxygen concentration increases. The optode sensors can however work in the whole region 0–100% oxygen saturation in water, and the calibration is done the same way as with the Clark type sensor. No oxygen is consumed and hence the sensor is stirring insensitive, but the signal will stabilize more quickly if the sensor is stirred after being put into the sample.

Popularity
Optical sensors are growing in popularity due to the low-cost, low power requirements and long term stability. They provide viable alternatives to electrode-based sensors or more complicated analytical instrumentation, especially in the field of environmental monitoring although in the case of oxygen optrodes, they do not have the resolution as the most recent cathodic microsensors.

See also
Oxygen sensor

References

Optical devices
Sensors
Spectroscopy
Fluorescence
Free Software Foundation of India. The Free Software Foundation of India (FSFI) is the Indian sister organisation to the US-based Free Software Foundation. It was founded in Thiruvananthapuram (Trivandrum) (the capital of Kerala) in 2001  as a non-profit Company. The FSFI advocates to promote the use and development of free software in India. This includes educating people about free software, including how it can help the economy of a developing country like India. FSF India regards non-free software as not a solution, but a problem to be solved.  Free software is sometimes locally called swatantra software in India.

In 2003, after meeting with FSF founder Richard Stallman, the President of India Dr. Abdul Kalam urged Indian computer scientists and professionals to use free and open-source software in research and development.

Logo
The left side of the FSF India logo resembles the famed Ashoka Chakra, that also appears on the Indian national flag, while its right half is a depiction of a compact disc. The combination of both symbols is intended to draw attention to the similarity between political freedom and free software, the latter of which the FSF promotes.

The Ashoka Chakra, in addition to being a long-standing Buddhist symbol depicting the wheel of time, also resembles Charkha of India's Freedom Struggle and thus in the current context, may symbolize the Indian independence movement which resulted in India's freedom from British occupation.

See also

 Free Software Foundation
 Free Software Foundation Europe
 Free Software Movement of India
 Free Software Movement

References

External links
  Free Software Foundation of India
 A LinuxJournal interview with FSF-India team members
 Slashdot and Hindu articles (dated 2002) regarding Stallman's visit to India.
 Slashdot and Hindu articles (dated 2002) regarding Dr. Kalam's endorsement of free software.
 A Blue-GNU interview: FSF India's Impact Far-Reaching

Free Software Foundation
Organisations based in Thiruvananthapuram
Software industry in India
Information technology organisations based in India
Organizations established in 2001
2001 establishments in Kerala
Grid Security Infrastructure. The Grid Security Infrastructure (GSI), formerly called the Globus Security Infrastructure, is a specification for secret, tamper-proof, delegatable communication between software in a grid computing environment. Secure, authenticatable communication is enabled using asymmetric encryption.

Authentication 
Authentication is performed using digital signature technology (see digital signatures for an explanation of how this works); secure authentication allows resources to lock data to only those who should have access to it.

Delegation 
Authentication introduces a problem: often a service will have to retrieve data from a resource independent of the user; in order to do this, it must be supplied with the appropriate privileges. GSI allows for the creation of delegated privileges: a new key is created, marked as a delegated and signed by the user; it is then possible for a service to act on behalf of the user to fetch data from the resource.

Security mechanisms 
Communications may be secured using a combination of methods:
 Transport Layer Security (TLS) can be used to protect the communication channel from eavesdropping or man-in-the-middle attacks.
 Message-Level Security can be used (although currently it is much slower than TLS).

References 

 A Security Infrastructure for Computational Grids by Ian Foster et al.
 A National-Scale Authentication Infrastructure by Randy Butler et al.

External links 
 Overview of the Grid Security Infrastructure

Grid computing
Cryptographic protocols
Twist compression tester. The Twist Compression Tester ("TCT") is a hydraulically operated bench-top apparatus used to evaluate the level of friction and/or wear between two materials under lubricated or non-lubricated conditions.

Under controlled conditions, a rotating annular specimen is brought into contact with a non-rotating flat specimen. Specimens can be prepared from die materials, sheet or plate materials, metals or plastics.

The applied normal force and the torque are measured, and the coefficient of friction is calculated.

Although the twist-compression test does not simulate an actual process, it has been demonstrated to correlate well with processes where boundary lubrication predominates and lubricant depletion occurs.

The Twist Compression Tester is an invaluable diagnostic tool for: evaluating lubricants, materials and coatings; screening products for production; understanding the effect of additives in a lubricant; and many other value-added testing scenarios.

The Twist Compression Tester was developed by Professor John Schey formerly of the University of Waterloo, and is manufactured, according to his design, under exclusive license by the Industrial Research + Development Institute (Midland, Ontario, Canada).  Tribsys is also manufacturing a twist compression machine and other approaches have been used with the Falex MCTT MultiContactTriboTester in thrust-washer configurations.

See also
Tribometer

References

Measuring instruments
Crobots. Crobots is a programming game released for the first time by Tom Poindexter in December, 1985 as Shareware. It is an MS-DOS program for IBM PC and compatibles and was developed on x86-based Unix systems.

The robots are controlled by a program written in a stripped-down version of C. The robot's mission is to seek out and destroy other robots, each running different programs. The robots can be controlled in order to move around the battlefield, scan the environment to find enemies and fire at enemies using a cannon.

Crobots borrows the concept used from the game RobotWar that ran on the original Apple II computer. Robots were programmed in a proprietary programming language that was interpreted and included a real-time view of the game as it was played.

In October, 2013, Poindexter released the source code of Crobots under the GPLv2 free software license.

Clones
There have been many Crobots clones made. However, very few of them are compiler and virtual machine at the same time; for example there are Java clones that use JVM and C++ clones that use a standard Microsoft compiler.

Proper clones have the same intrinsic functions as the original Tom Poindexter version; sometimes however the direction of angles is changed to match the standard C library's trigonometric functions. The most recent clones are Crobots64 and Netrobots.

Crobots64 by Marco Zora has a C++-subset compiler and a virtual machine with a graphical interface. New capabilities in this clone are cooperation between robots of the same species, the unlimited number of concurrent robots, the floating point math functions and the speed of the virtual CPU.

In contrast, Netrobots can run over a network with each robot running in a separate process, and each robot can be written in a different programming language.

See also 

 Core War

References

1985 video games
Programming games
Open-source video games
Freeware games
Commercial video games with freely available source code
Video games developed in the United States
VDL DB250. The VDL DB250 (originally the DAF DB250) is a twin-axle double-decker bus chassis manufactured by VDL Bus & Coach.

DB250

The DAF DB250 was launched in October 1991 and originally only available with Optare Spectra bodywork with 260 built, mainly for operators in the United Kingdom.

25 DAF DB250s with Optare Spectra bodywork were delivered to London Buses in 1992, with all but one delivered to the London Central subsidiary with a single door arrangement; Metroline received a single dual door example for evaluating replacements for MCW Metrobuses on route 16. Capital Logistics also received a delayed order of six dual door Spectras in 1999 for their operation of route 60.

31 left-hand drive examples were exported to Turkey in 1994, with 26 being delivered to IETT in Istanbul and the remaining five being delivered to İzulaş in İzmir.

The DAF DB250 later became available with Northern Counties Palatine II bodywork in 1994. Cowie London purchased 13 Palatine IIs on the DB250 chassis, while Harris Bus would also acquire fleets of DB250s.

DB250LF

The DB250LF, the low-floor version of the DB250, was the first low-floor double-decker bus chassis available in the United Kingdom. The DB250LF is readily identified by the centrally-exiting exhaust at the rear, which can cause problems with extreme changes of slope. A revised version of DB250LF was launched in 2004 as the DB250+. The design has received a number of modifications, one of which is the use of independent front suspension.

The first DB250LFs received Optare Spectra body, which was sold exclusively on the DB250. The first low-floor variant entered service on 4 February 1998 with Abus of Bristol, narrowly beating a Travel West Midlands DB250LF to operate the first low floor double-decker bus service in the UK. Travel West Midlands would later go on to order 20 more Spectras in 1999. Additional operators of the DB250LF with Optare Spectra bodywork included Reading Buses, who purchased 26, and Wilts & Dorset, who purchased 78.

Later DB250 chassis were fitted with Alexander ALX400, Plaxton President, East Lancs Myllennium Lowlander and Wright Pulsar Gemini bodies. The development of a Wright alternative arose because Arriva wished to buy both the Wright body and DB250 chassis. Unable to do so, it instead purchased over 100 Wright Eclipse Gemini bodied Volvo B7TLs. Wright subsequently developed the Pulsar Gemini in 2003 in order to win more orders from Arriva.

Arriva London purchased and acquired 632 DB250s between 1998 and 2005 with Alexander ALX400 (389), Plaxton President (110) and Wright Pulsar Gemini (133) bodywork. Arriva Midlands and Arriva Yorkshire also purchased examples.

The DB250LF chassis was also adopted by Wrightbus for the development of its hybrid-powered double-decker bus, the Wright Pulsar Gemini HEV.

Production of the DB250 ended in 2006, although examples continued entering service until 2008. Its successor, the Wright Gemini 2 integral double decker with VDL chassis modules, was launched in November 2008.

References

External links

Double-decker buses
Low-floor buses
DB250
Vehicles introduced in 1991