Summary

HandWiki is the world's largest wiki-style encyclopedia dedicated to science, technology and computing. It allows you to create and edit articles as long as you have external citations and login account. In addition, this is a content management environment that can be used for collaborative editing of original scholarly content, such as books, manuals, monographs and tutorials.

Expand All
Entries
Topic Review
Photo Manipulation
Photo manipulation involves transforming or altering a photograph using various methods and techniques to achieve desired results. Some photo manipulations are considered skillful artwork while others are frowned upon as unethical practices, especially when used to deceive the public. Other examples include being used for political propaganda, or to make a product or person look better, or simply for entertainment purposes or harmless pranks. Depending on the application and intent, some photo manipulations are considered an art form because it involves the creation of unique images and in some instances, signature expressions of art by photographic artists. For example, Ansel Adams employed some of the more common manipulations using darkroom exposure techniques, burning (darkening) and dodging (lightening) a photograph. Other examples of photo manipulation include retouching photographs using ink or paint, airbrushing, double exposure, piecing photos or negatives together in the darkroom, scratching instant films, or through the use of software-based manipulation tools applied to digital images. There are a number of software applications available for digital image manipulation, ranging from professional applications to very basic imaging software for casual users.
  • 29.8K
  • 08 Dec 2024
Topic Review
Antenna Aperture
In electromagnetics and antenna theory, antenna aperture, effective area, or receiving cross section, is a measure of how effective an antenna is at receiving the power of electromagnetic radiation (such as radio waves). The aperture is defined as the area, oriented perpendicular to the direction of an incoming electromagnetic wave, which would intercept the same amount of power from that wave as is produced by the antenna receiving it. Assume a plane wave in a particular direction has an irradiance or power flux density [math]\displaystyle{ S }[/math]; this is the amount of power passing through a unit area of one square meter. Then if an antenna delivers [math]\displaystyle{ P_o }[/math] watts to the load connected to its output terminals (e.g. the receiver) when irradiated by a uniform field of power density [math]\displaystyle{ S }[/math] watts per square meter, the antenna's aperture for the direction of that plane wave is [math]\displaystyle{ A_e }[/math] in square meters, given by: So the power received by an antenna (in watts) is equal to the power density of the electromagnetic energy (in watts per square meter), multiplied by its aperture (in square meters). Radio waves from a direction where the antenna's aperture is larger thus collect a greater amount of that wave's power; this is more often referred to as antenna gain. To actually obtain that available power [math]\displaystyle{ P_o }[/math], the incoming radiation must be in the state of polarization specified for that antenna, and the load (receiver) must be impedance matched to the antenna's feedpoint impedance. The meaning of aperture is thus based on a receiving antenna, however any receiving antenna can also be used for transmission. Due to reciprocity, an antenna's gain in receiving and transmitting are identical, so the power transmitted by an antenna in different directions (the radiation pattern) is always proportional to the effective area [math]\displaystyle{ A_e }[/math] in each direction; that proportionality factor is derived below. When no direction is specified, [math]\displaystyle{ A_e }[/math] (or "antenna gain") is understood to refer to its maximum value, that is, in the intended direction(s) that the antenna is designed to receive from and/or transmit toward.
  • 11.9K
  • 27 Oct 2022
Topic Review
Community Source
Community Source is a type of software development used in colleges and universities that builds on the practices of Free Software communities. The software of these collective efforts are distributed via an approved Free Software Foundation licence. Examples include the Sakai Project, Kuali, and Open Source Portfolio. Copyright for the software is often held by an independent foundation (organized as a 501c3 corporation in the United States ) modeled on the contributor agreements, licensing, and distribution practices of the Apache Foundation.
  • 1.6K
  • 24 Oct 2022
Topic Review
GameMaker Studio
GameMaker Studio (formerly Animo until 1999, Game Maker until 2011, GameMaker until 2012, and GameMaker: Studio until 2017) is a cross-platform game engine developed by YoYo Games. GameMaker accommodates the creation of cross-platform and multi-genre video games using a custom drag-and-drop visual programming language or a scripting language known as Game Maker Language, which can be used to develop more advanced games that could not be created just by using the drag and drop features. GameMaker was originally designed to allow novice computer programmers to be able to make computer games without much programming knowledge by use of these actions. Recent versions of software also focus on appealing to advanced developers.
  • 4.0K
  • 24 Oct 2022
Topic Review
Things
Things is a task management app for macOS, iPadOS, iOS, and watchOS made by Cultured Code, a software startup based in Stuttgart, Germany . It first released for Mac as an alpha that went out in late 2007 to 12,000 people and quickly gained popularity. The following July, when the App Store launched, it was among the first 552 apps available for iPhone. It was then released alongside the iPad in 2010, and became one of the first apps available for Apple Watch in 2015. In December 2013, Cultured Code announced that they had sold one million copies of the software to date, and in December 2014 the company announced that downloads had increased by an additional three million.
  • 1.5K
  • 24 Oct 2022
Topic Review
Archy
Archy is a software system whose user interface introduced a different approach for interacting with computers with respect to traditional graphical user interfaces. Designed by human-computer interface expert Jef Raskin, it embodies his ideas and established results about human-centered design described in his book The Humane Interface. These ideas include content persistence, modelessness, a nucleus with commands instead of applications, navigation using incremental text search, and a zooming user interface (ZUI). The system was being implemented at the Raskin Center for Humane Interfaces under Raskin's leadership. Since his death in February 2005 the project was continued by his team, which later shifted focus to the Ubiquity extension for the Firefox browser. Archy in large part builds on Raskin's earlier work with the Apple Macintosh, Canon Cat, SwyftWare, and Ken Perlin's Pad ZUI system. It can be described as a combination of Canon Cat's text processing functions with a modern ZUI. Archy is more radically different from established systems than are Sun Microsystems' Project Looking Glass and Microsoft Research's "Task Gallery" prototype. While these systems build upon the WIMP desktop paradigm, Archy has been compared as similar to the Emacs text editor, although its design begins from a clean slate. Archy used to be called The Humane Environment ("THE"). On January 1, 2005, Raskin announced the new name, and that Archy would be further developed by the non-profit Raskin Center for Humane Interfaces. The name "Archy" is a play on the Center's acronym, R-CHI. It is also an allusion to Don Marquis' archy and mehitabel poetry. Jef Raskin jokingly stated: "Yes, we named our software after a bug" (a cockroach), further playing with the meaning of bugs in software.
  • 745
  • 24 Oct 2022
Topic Review
Pashtun Tahafuz Movement
The Pashtun Tahafuz Movement (Pashto: پښتون ژغورنې غورځنګ‎, Urdu: پشتون تحفظ تحریک‎; abbreviated PTM), or the Pashtun Protection Movement, is a social movement for Pashtun human rights based in Khyber Pakhtunkhwa and Balochistan. Formerly called the Mahsud Tahafuz (or Protection) Movement, it was founded in May 2014 by eight students at Gomal University, Dera Ismail Khan as an initiative for removing landmines from Waziristan and other parts of the former Federally Administered Tribal Areas, affected by the war in North-West Pakistan.
  • 13.2K
  • 24 Oct 2022
Topic Review
Subjective Expected Relative Similarity (SERS)
Subjective expected relative similarity (SERS) is a normative and descriptive theory that predicts and explains cooperation levels in a family of games termed Similarity Sensitive Games (SSG), among them the well-known Prisoner's Dilemma game (PD). SERS was originally developed in order to (i) provide a new rational solution to the PD game and (ii) to predict human behavior in single-step PD games. It was further developed to account for: (i) repeated PD games, (ii) evolutionary perspectives and, as mentioned above, (iii) the SSG subgroup of 2x2 games. SERS predicts that individuals cooperate whenever their subjectively perceived similarity with their opponent exceeds a situational index derived from the game’s payoffs, termed the similarity threshold of the game. SERS proposes a solution to the rational paradox associated with the single step PD and provides accurate behavioral predictions. The theory was developed by Prof. Ilan Fischer at the University of Haifa.
  • 920
  • 24 Oct 2022
Topic Review
Cortana
Cortana is a virtual assistant developed by Microsoft which uses the Bing search engine to perform tasks such as setting reminders and answering questions for the user. Cortana is currently available in English, Portuguese, French, German, Italian, Spanish, Chinese, and Japanese language editions, depending on the software platform and region in which it is used. Microsoft began reducing the prevalence of Cortana and converting it from an assistant into different software integrations in 2019. It was split from Windows 10's search bar in April 2019. In January 2020, Cortana mobile app was removed from certain markets and in first half of 2021 Cortana mobile app was shut down globally.
  • 3.5K
  • 24 Oct 2022
Topic Review
Microsoft DoubleSpace BPB
DriveSpace (initially known as DoubleSpace) is a disk compression utility supplied with MS-DOS starting from version 6.0 in 1993 and ending in 2000 with the release of Windows Me. The purpose of DriveSpace is to increase the amount of data the user could store on disks by transparently compressing and decompressing data on-the-fly. It is primarily intended for use with hard drives, but use for floppy disks is also supported. This feature was removed in Windows XP and later.
  • 659
  • 24 Oct 2022
  • Page
  • of
  • 863
>>