Interfaces as functors, programs as coalgebras—A final coalgebra theorem in intensional type theory

In [P. Hancock, A. Setzer, Interactive programs in dependent type theory, in: P. Clote, H. Schwichtenberg (Eds.), Proc. 14th Annu. Conf. of EACSL, CSL’00, Fischbau, Germany, 21–26 August 2000, Vol. 1862, Springer, Berlin, 2000, pp. 317–331, URL citeseer.ist.psu.edu/article/hancock00interactive.html; P. Hancock, A. Setzer, Interactive programs and weakly final coalgebras in dependent type theory, in: L. Crosilla, P. Schuster (Eds.), From Sets and Types to Topology and Analysis. Towards Practicable Foundations for Constructive Mathematics, Oxford Logic Guides, Clarendon Press, 2005, URL www.cs.swan.ac.uk/csetzer/] Hancock and Setzer introduced rules to extend Martin-Löf's type theory in order to represent interactive programming. The rules essentially reflect the existence of weakly final coalgebras for a general form of polynomial functor. The standard rules of dependent type theory allow the definition of inductive types, which correspond to initial algebras. Coalgebraic types are not represented in a direct way. In this article we show the existence of final coalgebras in intensional type theory for these kind of functors, where we require uniqueness of identity proofs () for the set of states and the set of commands which determine the functor. We obtain the result by identifying programs which have essentially the same behaviour, viz. are bisimular. This proves the rules of Setzer and Hancock admissible in ordinary type theory, if we replace definitional equality by bisimulation. All proofs [M. Michelbrink, Verifications of final coalgebra theorem in: Interfaces as Functors, Programs as Coalgebras—A Final Coalgebra Theorem in Intensional Type Theory, 2005, URL www.cs.swan.ac.uk/csmichel/] are verified in the theorem prover agda [C. Coquand, Agda, Internet, URL www.cs.chalmers.se/catarina/agda/; K. Peterson, A programming system for type theory, Technical Report, S-412 96, Chalmers University of Technology, Göteborg, 1982], which is based on intensional Martin-Löf type theory.     

Coping with information technology challenges to identity: A theoretical framework

Drawing on ideas from identity control theory and coping theory and on a diverse range of social psychology literature, we propose an integrative theoretical framework that unpacks and traces the processes by which information technology comes to affect users’ identity. We define four types of strategies (acting on the situation, adjusting the self, cathartic practices and distancing) through which people cope with technological challenges to the self. We suggest that these strategies may lead to four individual-level outcomes, namely reinforced identity, redefined identity, ambivalent identity and anti-identity. The model is provided with a preliminary support through reference to real life situations, carefully selected from extant empirical IS enquiries.     

强磁场下微弱信号检测系统设计

摘要：强磁场环境下微弱信号的检测是利用硬件及软件对极易被噪声淹没的小信号进行提取。为了能在强干扰环境中,完成铝电解槽母线上的小电压信号的获取,从而设计了一套小电压信号检测的系统。系统分为硬件和软件两部分。论文从微小电压信号检测电路的硬件设计,软件设计和实验测试几个方面对检测系统进行介绍。硬件电路包括信号的放大电路,滤波电路。软件设计包括数据转换部分和人机界面编程部分,并通过实验验证系统的精度和实时性。     

On the existence of weak solutions of nonlinear degenerate parabolic system with variable exponents

The main goal of the present paper is establishing the existence and uniqueness of weak solutions for the nonlinear degenerate reaction–diffusion system with variable exponents. A model also is proposed to characterize the invasion of cancer cells towards healthy cells with acidification environment. Moreover, the main results of this paper are obtained using regularization problem, the Faedo–Galerkin approximation method, some apriori estimates, compactness results and the Gronwall Lemma.     

乙炔盘式输送上料及除尘自动控制系统

在介绍了回转盘输送机上料方式和脉冲袋式除尘器的控制流程的基础上,重点叙述了除尘控制系统的系统功能、软硬件构成。运行表明:此控制系统运行稳定可靠、操作简单,减轻了工人的劳动强度,值得推广。     

基于人脸识别技术的身份甄别辅助系统设计与实现

人脸识别技术广泛应用于反恐、公共要地安全防范、门禁、出入境控制、金融支付安全、物联网、考勤等领域,解决了身份验证问题,是理想的身份甄别方法.本文所涉及与实现的身份甄别辅助系统采用先进实用、技术难度大的主动近红外图像方案,攻克了人脸识中技术难题.既可以对人脸进行检测识别,又可以锁定目标嫌疑人,提供主动性报警;同时还可以对监控出中现的人员进行连续全天候的实时抓拍、记录、对比分析,自动生成身份甄别报告;是保密、安全、方便的身份甄别手段.     

Ready to preorder: The case of weak process semantics

Recently, Aceto, Fokkink and Ingólfsdóttir proposed an algorithm to turn any sound and ground-complete axiomatisation of any preorder listed in the linear time-branching time spectrum at least as coarse as the ready simulation preorder, into a sound and ground-complete axiomatisation of the corresponding equivalence—its kernel. Moreover, if the former axiomatisation is ω-complete, so is the latter. Subsequently, de Frutos Escrig, Gregorio Rodríguez and Palomino generalised this result, so that the algorithm is applicable to any preorder at least as coarse as the ready simulation preorder, provided it is initials preserving. The current paper shows that the same algorithm applies equally well to weak semantics: the proviso of initials preserving can be replaced by other conditions, such as weak initials preserving and satisfying the second τ-law. This makes it applicable to all 87 preorders surveyed in “the linear time-branching time spectrum II” that are at least as coarse as the ready simulation preorder. We also extend the scope of the algorithm to infinite processes, by adding recursion constants. As an application of both extensions, we provide a ground-complete axiomatisation of the CSP failures equivalence for BCCS processes with divergence.     

Fighting identity theft: The coping perspective

The proliferation of the online business transaction has led to a large number of incidents of identity theft, which have incurred expensive costs to consumers and e-commerce industries. Fighting identity theft is important for both online business and consumers. Although the practical significance of fighting identity theft has been of great interest, empirical studies on identity theft are very limited. Drawing upon coping behavior theories, this study examines two types of coping behaviors to fight identity theft (i.e., conventional coping and technological coping). Following structural equation modeling approach, we test the model using data collected from 117 subjects through a survey. The results reveal that both conventional coping and technological coping are effective to defend against identity theft. Technological coping is determined by an individual's conventional coping, self-efficacy, perceived effectiveness of coping, and social influence. This study presents a timely empirical study on identity theft, and provides valuable insights for consumers, government agencies, and e-commerce industries.     

具有身份识别功能的图书管理系统设计

在图书管理系统中增加读者身份鉴别功能能够加强对读者的管理.文章以读者的指纹特征作为图书流通系统中的身份识别,解决了流通中身份假冒的问题,从而维护了读者的权益.     

火电厂前馈式分段汽温调节系统开发与应用

在研究国内外火电厂自动化技术发展的基础上,分析了我国火电厂锅炉主汽温度调节系统的现状,提出了前馈式分段汽温调节系统的开发思想,并结合工程应用经验,描绘了其在火电厂控制系统中的应用前景。     

HCI as heterodoxy: Technologies of identity and the queering of interaction with computers

As digital technologies are woven more closely into identity formation, society needs ways to keep tools flexible to many versions of self-presentation and avoid perpetuating the political status quo through conservative and apolitical designing. This paper explores one route, drawing on Queer Theory to look at resistance to computer formalisation of identity through queering. Several case studies explore how we might apply the oblique route to design of a range of technologies that help users define themselves. In particular, forgetting, obscuring, cheating and eluding are activities held up to counter computer strengths and offer a more flexible vision of interaction design for the future.     

A parallel linear system solver

A new factorisation method for the solution of a linear system is proposed. The method is similar to an LU type factorisation of the coefficient matrix A where the factors are interlocking matrix quadrants and can be applied on a single-instruction stream parallel machine.     

电压型ICPT系统移相恒流的分析与设计

为了实现电压型ICPT系统输出电压的稳定,在对电压型ICPT系统进行模型推导的基础上,研究了采用移相恒流方式的SS型ICPT系统的各主要参数的关系,并依据推理设计了控制电路,最后设计基于UC3875控制的试验样机进行实验验证。     

Effects of underdamped step-varying second-order stochastic resonance for weak signal detection

Stochastic resonance (SR) has been proved to be an effective approach for weak signal detection. In this paper, an underdamped step-varying second-order SR (USSSR) method is proposed to further improve the output signal-to-noise ratio (SNR). In the method, by selecting a proper underdamped damping factor and a proper calculation step, the weak periodic signal, the noise and the potential can be matched with each other in the regime of second-order SR to generate an optimal dynamical system. The proposed method has three distinct merits as: 1) secondary filtering effect produces a low-noise output waveform; 2) good band-pass filtering effect attenuates the multiscale noise that locates in high- and (or) low-frequency domains; and 3) good anti-noise capability in detecting weak signal being submerged in heavy background noise. Numerical analysis and application verification are performed to confirm the effectiveness and efficiency of the proposed method in comparison with a traditional SR method.     

基于"哑铃式"运作模式的管理信息系统的设计

阐述了“哑铃式”企业运作模式及其特点,针对其特点分析其信息管理,实现了基于“哑铃式”企业运作模式的管理信息系统。     

基于经验小波变换的多通道微弱电流信号噪声控制

多通道微弱电流信号受很多噪声因素的干扰,导致微弱电流信号输出相对误差增加,为此提出基于经验小波变换的多通道微弱电流信号噪声控制方法。采集多通道微弱电流信号,利用经验小波变换技术分解采集到的微弱电流信号,判断电流信号中是否存在噪声并确定噪声类型。装设微弱电流信号噪声控制器,根据电流信号中的噪声量与噪声类型生成控制指令,对不同通道微弱电流信号噪声进行控制。实验结果表明,该方法的多通道微弱电流信号信噪比较高,输出信号与原信号之间的相对误差较小,可以实现多通道微弱电流信号噪声控制。     

嵌入式系统中48位高精度浮点类型的设计与实现

本文参考IEEE754标准,用无符号整型定义48位高精度浮点类型,详细给出了48位浮点类型与无符号32位整型相互转化及加减乘除的实现方法和流程图。算法已在ATMEL 89C55和PIC16F877中通过测试,并在基于SST9—三轴加速度传感器的控制处理中得到应用。     

The concept of strong and weak virtual reality

We approach the virtual reality phenomenon by studying its relationship to set theory. This approach offers a characterization of virtual reality in set theoretic terms, and we investigate the case where this is done using the wellfoundedness property. Our hypothesis is that non-wellfounded sets (so-called hypersets) give rise to a different quality of virtual reality than do familiar wellfounded sets. To elaborate this hypothesis, we describe virtual reality through Sommerhoff’s categories of first- and second-order self-awareness; introduced as necessary conditions for consciousness in terms of higher cognitive functions. We then propose a representation of first- and second-order self-awareness through sets, and assume that these sets, which we call events, originally form a collection of wellfounded sets. Strong virtual reality characterizes virtual reality environments which have the limited capacity to create only events associated with wellfounded sets. In contrast, the logically weaker and more general concept of weak virtual reality characterizes collections of virtual reality mediated events altogether forming an entirety larger than any collection of wellfounded sets. By giving reference to Aczel’s hyperset theory we indicate that this definition is not empty because hypersets encompass wellfounded sets already. Moreover, we argue that weak virtual reality could be realized in human history through continued progress in computer technology. Finally, within a more general framework, we use Baltag’s structural theory of sets (STS) to show that within this hyperset theory Sommerhoff’s first- and second-order self-awareness as well as both concepts of virtual reality admit a consistent mathematical representation. To illustrate our ideas, several examples and heuristic arguments are discussed.