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Topic Review
Serial Number Arithmetic
Many protocols and algorithms require the serialization or enumeration of related entities. For example, a communication protocol must know whether some packet comes "before" or "after" some other packet. The IETF (Internet Engineering Task Force) RFC 1982 attempts to define "Serial Number Arithmetic" for the purposes of manipulating and comparing these sequence numbers. This task is rather more complex than it might first appear, because most algorithms use fixed size (binary) representations for sequence numbers. It is often important for the algorithm not to "break down" when the numbers become so large that they are incremented one last time and "wrap" around their maximum numeric ranges (go instantly from a large positive number to 0, or a large negative number). Unfortunately, some protocols choose to ignore these issues, and simply use very large integers for their counters, in the hope that the program will be replaced (or they will retire), before the problem occurs (see Y2K). Many communication protocols apply serial number arithmetic to packet sequence numbers in their implementation of a sliding window protocol. Some versions of TCP use protection against wrapped sequence numbers (PAWS). PAWS applies the same serial number arithmetic to packet timestamps, using the timestamp as an extension of the high-order bits of the sequence number.
  • 729
  • 11 Oct 2022
Topic Review
Jem The Bee
JEM, the BEE is a Java, cloud-aware application which implements a Batch Execution Environment, to help and manage the execution of jobs, described by a Job Control Language (JCL). JEM, the BEE performs the following functions:
  • 729
  • 14 Oct 2022
Topic Review
CALL (DOS Command)
This article presents a list of commands used by DOS operating systems, especially as used on x86-based IBM PC compatibles (PCs). Other DOS operating systems are not part of the scope of this list. In DOS, many standard system commands were provided for common tasks such as listing files on a disk or moving files. Some commands were built into the command interpreter, others existed as external commands on disk. Over the several generations of DOS, commands were added for the additional functions of the operating system. In the current Microsoft Windows operating system, a text-mode command prompt window, cmd.exe, can still be used.
  • 728
  • 10 Oct 2022
Topic Review
Interactive Visualization
Interactive visualization or interactive visualisation is a branch of graphic visualization in computer science that involves studying how humans interact with computers to create graphic illustrations of information and how this process can be made more efficient. For a visualization to be considered interactive it must satisfy two criteria: One particular type of interactive visualization is virtual reality (VR), where the visual representation of information is presented using an immersive display device such as a stereo projector (see stereoscopy). VR is also characterized by the use of a spatial metaphor, where some aspect of the information is represented in three dimensions so that humans can explore the information as if it were present (where instead it was remote), sized appropriately (where instead it was on a much smaller or larger scale than humans can sense directly), or had shape (where instead it might be completely abstract). Another type of interactive visualization is collaborative visualization, in which multiple people interact with the same computer visualization to communicate their ideas to each other or to explore information cooperatively. Frequently, collaborative visualization is used when people are physically separated. Using several networked computers, the same visualization can be presented to each person simultaneously. The people then make annotations to the visualization as well as communicate via audio (i.e., telephone), video (i.e., a video-conference), or text (i.e., IRC) messages.
  • 705
  • 25 Nov 2022
Topic Review
Compressed Volume File
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.
  • 704
  • 22 Nov 2022
Topic Review
Neural Network for Dense Non-Rigid Structure from Motion
Non-rigid Structure from Motion (NRSFM) is a significant research direction in computer vision that aims to estimate the 3D shape of non-rigid objects from videos.
  • 700
  • 24 Oct 2023
Topic Review
Veronese Bellringing Art
Veronese bellringing art is a style of ringing church bells that developed around Verona, Italy from the eighteenth century. The bells are rung full circle (mouth uppermost to mouth uppermost), being held up by a rope and wheel until a note is required.
  • 699
  • 07 Nov 2022
Topic Review
Medical Data Breach
Medical data, including patients' identity information, health status, disease diagnosis and treatment, and biogenetic information, not only involve patients' privacy but also have a special sensitivity and important value, which may bring physical and mental distress and property loss to patients and even negatively affect social stability and national security once leaked. However, the development and application of medical AI must rely on a large amount of medical data for algorithm training, and the larger and more diverse the amount of data, the more accurate the results of its analysis and prediction will be. However, the application of big data technologies such as data collection, analysis and processing, cloud storage, and information sharing has increased the risk of data leakage. In the United States, the rate of such breaches has increased over time, with 176 million records breached by the end of 2017. There have been 245 data breaches of 10,000 or more records, 68 breaches of the healthcare data of 100,000 or more individuals, 25 breaches that affected more than half a million individuals, and 10 breaches of the personal and protected health information of more than 1 million individuals.
  • 699
  • 25 Nov 2022
Topic Review
Multi-Environment Real-Time
Multi-Environment Real-Time (MERT), later renamed UNIX Real-Time (UNIX-RT), is a hybrid time-sharing and real-time operating system developed in the 1970s at Bell Labs for use in embedded minicomputers (especially PDP-11s). A version named Duplex Multi Environment Real Time (DMERT) was the operating system for the AT&T 3B20D telephone switching minicomputer, designed for high availability; DMERT was later renamed Unix RTR (Real-Time Reliable). A generalization of Bell Labs' time-sharing operating system Unix, MERT featured a redesigned, modular kernel that was able to run Unix programs and privileged real-time computing processes. These processes' data structures were isolated from other processes with message passing being the preferred form of interprocess communication (IPC), although shared memory was also implemented. MERT also had a custom file system with special support for large, contiguous, statically sized files, as used in real-time database applications. The design of MERT was influenced by Dijkstra's THE, Hansen's Monitor, and IBM's CP-67. The MERT operating system was a four-layer design, in decreasing order of protection: The standard supervisor was MERT/UNIX, a Unix emulator with an extended system call interface and shell that enabled the use of MERT's custom IPC mechanisms, although an RSX-11 emulator also existed.
  • 697
  • 27 Oct 2022
Topic Review
Malayalam – Island of Mysteries
Malayalam – Island of Mysteries is a puzzle adventure video game developed by MJK Games in 2007-2008, and released as freeware for Windows on November 10, 2008. The game is a vague crossover between a Robinson Crusoe-themed survival game and a mysterious adventure similar to the Lost (TV series), presented in a cartoonesque style with hand-drawn graphics and animation.
  • 696
  • 18 Oct 2022
Topic Review
Virtual and Physical Robot Arms Using Augmented Reality
The use of robot arms in various industrial settings has changed the way tasks are completed. However, safety concerns for both humans and robots in these collaborative environments remain a critical challenge. Traditional approaches to visualising safety zones, including physical barriers and warning signs, may not always be effective in dynamic environments or where multiple robots and humans are working simultaneously. Mixed reality technologies offer dynamic and intuitive visualisations of safety zones in real time, with the potential to overcome these limitations.
  • 696
  • 31 Oct 2023
Topic Review
Multi-Eye to Robot Indoor Calibration Dataset
The METRIC dataset comprises more than 10,000 synthetic and real images of ChAruCo and checkerboard patterns. Each pattern is securely attached to the robot's end-effector, which is systematically moved in front of four cameras surrounding the manipulator. This movement allows for image acquisition from various viewpoints. The real images in the dataset encompass multiple sets of images captured by three distinct types of sensor networks: Microsoft Kinect V2, Intel RealSense Depth D455, and Intel RealSense Lidar L515. The purpose of including these images is to evaluate the advantages and disadvantages of each sensor network for calibration purposes. Additionally, to accurately assess the impact of the distance between the camera and robot on calibration, researchers obtained a comprehensive synthetic dataset. This dataset contains associated ground truth data and is divided into three different camera network setups, corresponding to three levels of calibration difficulty based on the cell size.
  • 694
  • 09 Jun 2023
Topic Review
Assertion (Software Development)
In computer programming, specifically when using the imperative programming paradigm, an assertion is a predicate (a Boolean-valued function over the state space, usually expressed as a logical proposition using the variables of a program) connected to a point in the program, that always should evaluate to true at that point in code execution. Assertions can help a programmer read the code, help a compiler compile it, or help the program detect its own defects. For the latter, some programs check assertions by actually evaluating the predicate as they run. Then, if it is not in fact true – an assertion failure – the program considers itself to be broken and typically deliberately crashes or throws an assertion failure exception.
  • 691
  • 31 Oct 2022
Topic Review
Wildcard DNS Record
A wildcard DNS record is a record in a DNS zone that will match requests for non-existent domain names. A wildcard DNS record is specified by using a * as the leftmost label (part) of a domain name, e.g. *.example.com. The exact rules for when a wild card will match are specified in RFC 1034, but the rules are neither intuitive nor clearly specified. This has resulted in incompatible implementations and unexpected results when they are used.
  • 689
  • 20 Oct 2022
Topic Review
Augmented and Virtual Reality Exergames for Elderly People
Augmented and virtual reality (AR/VR) can be used in the context of the exergames to train motor and cognitive skills in the elderly population for health improvement.
  • 689
  • 04 Feb 2024
Topic Review
National Council of Teachers of Mathematics
Founded in 1920, The National Council of Teachers of Mathematics (NCTM) is the world's largest mathematics education organization. NCTM holds annual national and regional conferences for teachers and publishes five journals.
  • 684
  • 10 Nov 2022
Topic Review
MDBPB
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.
  • 682
  • 15 Nov 2022
Topic Review
Virtual Reality Technologies Supporting Screening Oculomotor Problems
Oculomotor dysfunctions (OMDs) are problems relating to coordination and accuracy of eye movements for processing visual information. Eye-tracking (ET) technologies show great promise in the identification of OMDs. Virtual Reality (VR) and ET technologies emerged in the field of vision science, integrating built-in eye trackers into head-mounted displays (HMDs). Therefore, today, VR has the potential to be an effective tool in complementing the treatment of a variety of vision disorders requiring ET technologies for identification or treatment, e.g., treating amblyopia and convergence insufficiency.
  • 682
  • 25 Jul 2023
Topic Review
Touhou Hisōtensoku
Touhou Hisōtensoku ~ Chōdokyū Ginyoru no Nazo wo Oe (東方非想天則 ～ 超弩級ギニョルの謎を追え, lit. "Lacking Perception of the Rule of Heaven in the East: Chase the Enigma of the Superdreadnought Guignol") is a versus fighting game in the Touhou Project game series. The game, by Twilight Frontier and Team Shanghai Alice, can be played as a standalone game or as an expansion pack for the previous fighting game Scarlet Weather Rhapsody. In the Touhou Project overall, it is labeled as the 12.3rd Touhou game.
  • 677
  • 06 Oct 2022
Topic Review
Domain Name Registrar
A domain name registrar is a company that manages the reservation of Internet domain names. A domain name registrar must be accredited by a generic top-level domain (gTLD) registry or a country code top-level domain (ccTLD) registry. A registrar operates in accordance with the guidelines of the designated domain name registries.
  • 672
  • 17 Oct 2022
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