Time, Narratives and Participation Frameworks in Software Troubleshooting

The paper problematizes diagnostic work as a solely technical and rational activity by presenting an analysis focused on the social and organizational practices in which diagnosis is embedded. The analysis of a troubleshooting episode in an Italian internet company shows how diagnostic work is realized: 1) through collaboration sustained by specific knowledge distribution among designers (different but overlapping competences); 2) intersubjectively and discursively as an activity characterized by specific and diverse forms of participation and interwined with material intervention in the system; 3) following a situated rationality which proceeds by gradual approximations to achieve partial or provisional solutions while also taking account of organizational goals and needs. In particular the paper discusses how diagnosis is shaped by time pressure, flexible roles and distributed responsibilities, absent participants, narratives as specialized discourses.     

基于地域文化的餐饮空间设计探讨

本文针对当前餐饮空间设计中所存在的设计趋同现象,初步探讨了地域文化在餐饮空间设计中的设计定位,并依据国内有代表性的设计案例,论述了地域文化在餐饮空间中的具体表现方法和创新途径,从而进一步强调了基于地域文化的室内设计对于发展本土化室内设计走向国际的重要意义。     

Interaction in Time and Space

Distributed π-calculus and ambient calculus are extended with timers which may trigger timeout recovery processes. Timers provide a useful notion of relative time with respect to the interaction in a distributed system. The rather flat notion of space in timed distributed π-calculus is improved by considering a hierarchical representation of space in timed mobile ambients. Some basic results are proven, making sound both formal approaches. An easily understood example is used for both extensions, showing how it is possible to describe a non-monotonic behaviour and use a decentralized control to coordinate the interacting components in time and space.     

Deferred Correction in Space and Time

High order implicit methods are constructed for the solution of first order hyperbolic systems of PDE. The methods are based on the deferred correction principle in both space and time, and require only p/2 stages at each timestep for achieving accuracy of order p. Furthermore, they are suitable for applying domain decomposition techniques for implementation on parallel computers.     

Formalization of Time and Space

Time and space limitations can be specified, and proven, in exactly the same way as functionality. Proofs of time bounds, both implementation-independent and real-time, and of space requirements, both worst-case and average-case, are given in complete detail. Received May 1997 / Accepted in revised form July 1998     

View and Time Interpolation in Image Space

The ability to interpolate between images taken at different time and viewpoints directly in image space opens up new possiblities. The goal of our work is to create plausible in‐between images in real time without the need for an intermediate 3D reconstruction. This enables us to also interpolate between images recorded with uncalibrated and unsynchronized cameras. In our approach we use a novel discontiniuity preserving image deformation model to robustly estimate dense correspondences based on local homographies. Once correspondences have been computed we are able to render plausible in‐between images in real time while properly handling occlusions. We discuss the relation of our approach to human motion perception and other image interpolation techniques.     

冗余等待时间建模及匝道多目标协调控制

针对匝道等待时间描述中存在信息缺失的问题,结合排队论提岀了一种新的冗余等待时间概念并建模分析.以此为基础,给出了匝道多目标协调控制方程,并以径向基为核函数设计了一种基于支持向量机的匝道控制律求解方法,利用高速公路联络线转向城市快速路的高峰时段实例数据进行仿真.实验结果表明,与其它控制方法相比,所提的模型和算法在描述匝道状态和规避冗余等待等方面的效果更优.     

A Potential-Field Approach to Financial Time Series Modelling

We present a new approach to the problem of time series modelling that captures the invariant distribution of time series data within the model. This is particularly relevant in modelling economic and financial time series, such as oil prices, that exhibit clustering around a few preferred market modes. We propose a potential function approach which determines the function that governs the underlying time series process. This approach extends naturally to modelling multivariate time series. We show how to estimate the potential function for dimensions one and higher and use it to model statistically the evolution of the time series. An illustration of the procedure shows that testing the resulting model against historical data of oil prices captures the essential price behavior remarkably well. The model allows the generation of copies of the observed time series as well as providing better predictions by reducing uncertainty about the future behavior of the time series.     

限制期条件下的应急过程可靠性建模及仿真

应急过程本身可靠性是应急任务完成的基础,过程的不同任务阶段必须在相应的应急限制期内启动。利用UML建立限制期条件下的应急过程模型,并建立了应急过程可靠性模型,提供了将UML模型转化为Petri网可靠性仿真模型的具体方法,最后对实例通过计算机仿真进行了大量的计算,对仿真结果进行了分析。     

限制期条件下的应急过程可靠性建模及仿真

应急过程本身可靠性是应急任务完成的基础，过程的不同任务阶段必须在相应的应急限制期内启动。利用UML建立限制期条件下的应急过程模型，并建立了应急过程可靠性模型，提供了将UML模型转化为Petri网可靠性仿真模型的具体方法，最后对实例通过计算机仿真进行了大量的计算，对仿真结果进行了分析。     

Integral and Functional Transformations in Space and Time Domains with Voids

Integral and functional transformations of continuous and discrete inputs of linear dynamic systems in space and time domains with hollow inclusions are investigated. Space and time boundary conditions can be given on boundaries of these inclusions. Their influence on the output functions of the systems being considered is simulated by dummy external-dynamic factors acting in them. The precision and uniqueness of such simulation are examined.     

天线辐射功率的时空分布仿真

在涉及到天线的仿真中,天线辐射功率时空分布的计算和建模是一个关键问题,对仿真结果的逼真度有重要影响。对影响天线辐射功率分布的主要因素进行了分析,认为在现代高科技条件下,执行重要任务的各种天线往往要频繁的发射不同波长的信号,这时天线的最大增益是变化的,在分析和仿真辐射功率分布时应根据不同的发射频率实时求解最大增益。推导了天线发射不同波长信号时的最大增益求懈方法,然后归纳总结了对天线辐射功率的时空分布进行仿真的方法和步骤,并以一个示例来具体说明仿真过程。所论述的方法已应用到某型模拟训练器项目中,实际应用证明可行。     

Time and Space Lower Bounds for Implementations Using k-CAS

This paper presents lower bounds on the time and space complexity of implementations that use k-compare&swap (k-CAS) synchronization primitives. We prove that using k-CAS primitives can improve neither the time nor the space complexity of implementations of widely used concurrent objects, such as counter, stack, queue, and collect. Surprisingly, overly restrictive use of k-CAS may even increase the space complexity required by such implementations. We prove a lower bound of Omega (log_2 n) on the round complexity of implementations of a collect object using read, write, and k-CAS, for any k, where n is the number of processes in the system. There is an implementation of collect with O(log_2 n) round complexity that uses only reads and writes. Thus, our lower bound establishes that k-CAS is no stronger than read and write for collect implementation round complexity. For k-CAS operations that return the values of all the objects they access, we prove that the total step complexity of implementing key objects such as counters, stacks, and queues is Omega (n log_k n). We also prove that k-CAS cannot improve the space complexity of implementing many objects (including counter, stack, queue, and single-writer snapshot). An implementation has to use at least n base objects even if k-CAS is allowed, and if all operations (other than read) swap exactly k base objects, then it must use at least k cdot n base objects.     

Time and Space Issues in the Generation of Graph Transition Systems

GROOVE is a tool for the automatic generation of graph transition systems from graph grammars. In this type of tool, both memory and time performance are of prime importance. In this paper we discuss the implementation techniques used for optimising the tool in this regard, and we list possible future improvements.     

空时码不对称调制方法研究

提出了空时编码不对称调制方案。软件分析了比特交织空时编码调制系统在Rayleigh衰落信道下的成对错误概率上界。对于常用的几种映射方案,采用不对称调制星座图,可以增大汉明距离为1的调制符号间的最小欧氏距离,从而提高系统的编码增益和分集增益,降低成对错误概率的上界。理论分析和仿真结果表明,不对称调制星座图改善了比特交织空时编码调制系统在Rayleigh信道下的性能,并且没有牺牲频谱效率和增加系统复杂性的代价。     

模糊RBF神经网络在时间序列建模中的应用

本文针对时间序列传统ＡＲ建模精度及算法的局限性,提出使用模糊ＲＢＦ神经网络对信号进行建模的方法,仿真结果表明,该方法具有良好的预测效果。