What is a "Distributed" Data Processing System?

Words have only one purpose in a technical context–the transmission of information. When they fail to do that, they lead to confusion and misunderstanding. "Distributed data processing" and "distributed processing" are two phrases which illustrate that axiom. Like many other words in the lexicon of the computer professional, these have become cliches through over-use, losing much of their original meaning in the process. This paper is an attempt to reverse that trend.     

Bootloader的分析和设计

介绍了Bootloader的操作模式、与主机的通信，说明了Bootloader的两阶段任务——汇编语言编写的固化代码执行部分和C语言编写的基于RAM执行部分，并通过对Blob源代码的分析，介绍了Blob所实现的功能，从而对Bootloader有更深刻的理解，并提出了设计Bootloader应该注意的问题。     

The Technology Underlying Podcasts

Podcasting is a combination of "iPod," Apple's well-known portable media device, and "broadcast." Podcast has two meanings. First, podcasting is the transmission of multimedia files over the Internet. Rather than being received and opened with different plug-ins, podcast files are ready for viewing on either a PC or other devices, such as an iPod. On the PC, users can treat podcast files like any other computer files, viewing them immediately or saving them for viewing at a later date. Second, in addition to the delivery of files, podcast also refers to their content. Frequently, podcasts are files that are sent at regular intervals. Once viewers determine which podcasts they want, they sign up for them and have them delivered automatically whenever their receiving device is connected to the Internet     

Interpolation synthesis of articulated figure motion

Most conventional media depend on engaging and appealing characters. Empty spaces and buildings would not fare well as television or movie programming, yet virtual reality usually offers up such spaces. The problem lies in the difficulty of creating computer generated characters that display real time, engaging interaction and realistic motion. Articulated figure motion for real time computer graphics offers one solution to this problem. A common approach stores a set of motions and lets you choose one particular motion at a time. The article describes a process that greatly expands the range of possible motions. Mixing motions selected from a database lets you create a new motion to exact specifications. The synthesized motion retains the original motions' subtle qualities, such as the realism of motion capture or the expressive, exaggerated qualities of artistic animation. Our method provides a new way to achieve inverse kinematics capability-for example, placing the hands or feet of an articulated figure in specific positions. It proves useful for both real time graphics and prerendered animation production. The method, called interpolation synthesis, is based on motion capture data and it provides real time character motion for interactive entertainment or avatars in virtual worlds     

Possible Ontologies: How Reality Constrains the Development of Relevant Ontologies

For years, ontologies have been known in computer science as consensual models of domains of discourse, usually implemented as formal definitions of the relevant conceptual entities. Researchers have written much about the potential benefits of using them, and most of us regard ontologies as central building blocks of the semantic Web and other semantic systems. Unfortunately, the number and quality of actual, "non-toy" ontologies available on the Web today is remarkably low. This implies that the semantic Web community has yet to build practically useful ontologies for a lot of relevant domains in order to make the semantic Web a reality. Theoretically minded advocates often assume that the lack of ontologies is because the "stupid business people haven't realized ontologies' enormous benefits." As a liberal market economist, the author assumes that humans can generally figure out what's best for their well-being, at least in the long run, and that they act accordingly. In other words, the fact that people haven't yet created as many useful ontologies as the ontology research community would like might indicate either unresolved technical limitations or the existence of sound rationales for why individuals refrain from building them - or both. Indeed, several social and technical difficulties exist that put a brake on developing and eventually constrain the space of possible ontologies     

Calculation algorithm for the collisional moments of the Boltzmann equation for Maxwell molecules

We present in this paper an analytical calculation algorithm of the collisions integrals for the Maxwell's particles. This algorithm is tested by a program written in Maple V and carried out on a personal computer. The formulas obtained of these integrals whose order is lower or equal to 5 are identical to those of Truesdell (1980), those whose order is equal to 6, 7 and 8 are presented at the end of this paper. Even if the resulting formulas for high orders become large, they remain always short and handy compared to those which correspond to the original formula given by the theorem of Truesdell-Muncaster (1980). However, the limits of this algorithm depend only on the capacities of the treating machine.     

Time-segmentation and position-free recognition of air-drawn gestures and characters in videos

We report the recognition in video streams of isolated alphabetic characters and connected cursive textual characters, such as alphabetic, hiragana and kanji characters, that are drawn in the air. This topic involves a number of difficult problems in computer vision, such as the segmentation and recognition of complex motion on videos. We use an algorithm called time–space continuous dynamic programming (TSCDP), which can realize both time- and location-free (spotting) recognition. Spotting means that the prior segmentation of input video is not required. Each reference (model) character is represented by a single stroke that is composed of pixels. We conducted two experiments involving the recognition of 26 isolated alphabetic characters and 23 Japanese hiragana and kanji air-drawn characters. We also conducted gesture recognition experiments based on TSCDP, which showed that TSCDP was free from many of the restrictions imposed by conventional methods.     

Images of self and others as computer users: the role of gender and experience

Abstract Gender differences in the pursuit of technology careers are a current issue of concern. We report on two studies that use surveys, drawings and interviews to examine sixth- and eighth-grade students' perceptions of knowledgeable computer users and their self-perception as a computer-type person. In Study 1, participants were asked to generate representations of computer users in pictures or words. The results indicate that the majority of representations were of male users and they frequently wore glasses. Students of both genders were more likely to draw males. Eighth-grade students' representations included more stereotypical features than those of sixth-grade students. In Study 2, students were asked whether they believed that there was such a thing as a computer-type person and whether they perceived themselves to be one. Eighty per cent of students rejected this characterization. They differed from students who accepted it in their levels of past experience, their confidence, and the probability that they shared their knowledge with others. The results of both studies suggest that while there is a male image of computer science in general, it is not overly negative and students' self-perception is not governed by their own gender as much as by other variables.     

Some factors affecting elementary teachers' use of the computer

A survey of 70 fourth and fifth grade elementary teachers revealed several interesting factors, not documented elsewhere, that affect teachers' use of the computer. First, very few teachers themselves owned computers or used them for personal reasons at home or school. Second, most teachers felt that neither they nor the students should be held accountable for the teaching or learning of computer objectives. Third, teachers were perplexed as to how to manage students who were not able to take their turn on the computer. Fourth, several teachers chose not to use district-provided sources written to help them implement the computer. Fifth, most teachers had little understanding of the scope and sequence of the district's computer curriculum and how their grade level fit into this. Sixth, most teachers felt that they were allotted too little time to teach computers each week.     

On the Convergence Acceleration of Slowly Convergent Sums Involving Oscillating Terms

In this paper, an acceleration technique based on a Kummer’s transformation method is developed for some slowly convergent series. The original series is decomposed into two parts; one part being rapidly convergent and the other part being slowly convergent. Then the series in the slowly convergent part is expressed as integrals of some auxiliary functions and subsequently they are written in terms of polynomials whose coefficients are given by the zeta functions. The given method is computationally oriented and does not involve much analytic effort. A numerical example is provided to illustrate the usage and the efficiency of the method.     

设计创作灵感的主要来源——对写生实践和手绘草图的几点认识

电脑技术的广泛运用,使人们在设计中过分依赖电脑,对写生和手绘草图的训练失去了应有的热情,最终导致设计者的造型能力和思维能力降低。本文主要是讨论写生和手绘草图的重要性,根据"眼、脑、手、图形"四位一体原则,分别从视觉,大脑,动手和图形表达这几个方面分析了它们的关系和相互作用,并强调它们在启发设计思维和创作灵感中的意义。并希望人们在熟练运用电脑的同时,重视手上功夫的训练,保持设计原创的灵感和热情。     

ANALYSIS: Software for Graphical Analysis of Multidimensional Flow Cytometric List Mode Data

A computer program for graphical analysis of multidimensional flow cytometric list mode data is described. The program offers one-, two-, and three-dimensional inspection of an amount of data that is only limited by disk space. Subpopulations within the original data set can be identified by setting one or more two-dimensional AND gates around them. The order of measurement can be used as a parameter for evaluation of time-dependent processes. Other new parameters can be made by zooming in on a parameter, logarithmic transformation, or division of two parameters. The program is written in Turbo Pascal and it can run on any MS-DOC PC with an EGA/VGA resolution screen.     

Does the Medium Make a Difference? Two Studies of Writing With Pen and Paper and With Computers

This article reports two studies examining how the use of computer technology affects writers' processes and resulting written products. The first experiment, a partial replication of Gould's (1981) study, compared the efficiency and quality of 15 experienced writers' persuasive letters written in three counterbalanced conditions: pen and paper, standard personal computer, and advanced workstation. Analyses of time to compose and length of the resulting letters showed that when composing with the advanced work-stations, writers wrote for longer periods of time and composed longer letters than when composing with pen and paper. Rate of composition (words per min) was similar in all three conditions. Scores for content quality, mechanics quality, and total quality were also collected and analyzed. Letters composed with the personal computer were poorer in content quality and total quality. There were no differences in mechanics quality. In the second experiment, 8 of the original 15 writers revised two of their letters in the medium with which they were composed. Think-aloud protocols collected while the writers revised their letters were collected and analyzed. When revising with pen and paper, writers planned more than when revising on-line; they also planned more before beginning their revisions. However, when revising in the computer conditions, writers reread their texts more and paid more attention to the medium than when revising on paper.     

The construct of a high-level computer language for programmable assembly

In recent years, considerable effort has been devoted to developing and extending programming languages for manipulation of computer-controlled robotic arms for various tasks. The present trend is to develop high-level languages that simplify the programming task so that they can be used by a less well-trained person with ease and speed. In this article, the information required for assembly is examined and a construct of a new computer language is proposed. An example of a computer program using the proposed language for assembling a pencil sharpener is given. This program is compared with similar program written in another language currently being developed and extended.     

Pathologies of AI: Responsible use of artificial intelligence in professional work

Although the AI paradigm is useful for building knowledge-based systems for the applied natural sciences, there are dangers when it is extended into the domains of business, law and other social systems. It is misleading to treat knowledge as a commodity that can be separated from the context in which it is regularly used. Especially when it relates to social behaviour, knowledge should be treated as socially constructed, interpreted and maintained through its practical use in context. The meanings of terms in a knowledge-base are assumed to be references to an objective reality whereas they are instruments for expressing values and exercising power. Expert systems that are not perspicuous to the expert community will lose their meanings and cease to contain genuine knowledge, as they will be divorced from the social processes essential for the maintenance of both meaning and knowledge. Perspicuity is usually sacrificed when knowledge is represented in a formalism, with the result that the original problem is compounded with a second problem of penetrating the representation language. Formalisms that make business and legal problems easier to understand are one essential research goal, not only in the quest for intelligent machines to replace intelligent human beings, but also in the wiser quest for computers to support collaborative work and other forms of social problem solving.     

Hierarchical multi-level computer network for laboratory automation

The design and implementation of a microcomputer network to support laboratory automation is described and discussed. It is a multi-level hierarchical star network connected to a multiprogrammed computer on which all program development is done. The system is capable of supporting a large number of experimental setups. The microcomputers are either used as (1) local microcomputers for experiment control, (2) multiplexers for other microcomputers or (3) controllers for peripherals known in the multiprogrammed computer. The system combines the advantages of a large multiprogrammed computer with those of a small cheap dedicated computer close to the experiment. Character-oriented peripherals are connected to the multiprogrammed computer only. This reduces the amount of system software to be written for the network by an order of magnitude and eliminates the need for interfacing to existing small computer software. The system software consist of three small programs (monitors) providing a process concept and multibuffering of data in the involved computers. The monitor establishes a hierarchy of control and they eliminate the need for any local load device for the microcomputers as their monitors are in a read-only store. The system developed is designed for control of experiments in an environment where the experiments and the control strategies change with time and where the data refinement required is beyond what can be done on the present generation of microcomputers.     

General controls in computer systems

Because almost all business organizations own or will shortly own computer systems, auditors can no longer treat the computer as a “black box” to be ignored when attesting to the fairness with which financial statements present financial position and results of operations. This paper is primarily written for auditors who are becoming involved in auditing computerized accounting systems. It covers in detail general controls in computer systems, the first and most important category of controls evaluated by an auditor. General controls relate to all EDP activities; they span all jobs processed on the computer system. When they are weak or non-existing, the auditor must expand his testing of the entire computer system, often at considerable additional cost to the client.     

An Algol 68 based algebraic manipulation system

Although the topic of algebraic manipulation by computer is an old one, it is still a characteristic of many algebraic manipulation systems that they often neglect the needs and characteristics of the end user. This paper describes an algebraic manipulation system, written in Algol 68, which attempts to remedy this state of affairs.     

Principles to Support Modular Software Construction

The construction of large software systems is always achieved through assembly of independently written components — program modules. For these software components to work together, they must share a common set of data types and principles for representing structured data such as arrays of values and files. This common set of tools for creating and operating on data objects is provided by the infrastructure of the computer system: the hardware, operating system and runtime code. Because the nature and properties of these tools are crucial for correct operation of software components and their inter-operation, it is essential to have a precise specification that may be used for verifying correctness of application software on one hand, and to verify correctness of system behavior on the other. We call such a specification a program execution model (PXM). It is evident that the properties of the PXM implemented by a computer system can have serious impact on the ability of application programmers to practice modular software construction. This paper discusses the concept of program execution models and presents a set of principles that a PXM must satisfy to provide a sound basis for modular software construction. Because parallel program execution on computer systems with many processing units is an essential part of contemporary computing environments, the expression of parallelism and modular software construction using components involving parallel operations is included in this treatment. The conclusion is that it is possible to build computer systems that implement a PXM within which any parallel program may be used, unmodified, as a component for building more substantial parallel programs.     

Mobile technology for crime scene examination

In this paper, the concept of distributed cognition is used to inform the design, development and trialling of technologies to support Crime Scene Examination is reported. A user trial, with trainee Crime Scene Examiners, was conducted to compare the ways in which evidence search and recovery could be combined with the production of a crime scene report (that must be written at the scene). Participants completed the crime scene report using either the conventional paper form, an electronic form on a tablet computer (to represent the current trend in digitisation of crime scene reports), or a wearable computer (with speech input). While both computer conditions (tablet and wearable) led to faster performance, when compared with the paper condition, there was no difference in content or quality of the reports produced in any of the three conditions; thus, the computer conditions produced acceptable reports in much faster time when compared to conventional practice. Furthermore, activity sampling analysis showed that participants found it much easier to integrate the wearable computer (than either paper forms or tablet computer) into their search and recovery activity.