架空跨海电缆净空高度动态监测系统设计

根据架空跨海电缆的特点,设计了一种以单片机为中心的净空高度动态监测系统。文中给出了一些主要硬件模块的设计方法和GPS数据的解析程序。经实验测试,该系统能有效地保证电缆的安全运行。     

Software monitoring through formal specification animation

This paper presents a formal specification-based software monitoring approach that can dynamically and continuously monitor the behaviors of a target system and explicitly recognize undesirable behaviors in the implementation with respect to its formal specification. The key idea of our approach is in building a monitoring module that connects a specification animator with a program debugger. The requirements information about expected dynamic behaviors of the target system are gathered from the formal specification animator, while the actual behaviors of concrete implementations of the target system are obtained through the program debugger. Based on the information obtained from both sides, the judgement on the conformance of the concrete implementation with respect to the formal specification is made timely while the target system is running. Furthermore, the proposed formal specification-based software monitoring technique does not embed any instrumentation codes to the target system nor does it annotate the target system with any formal specifications. It can detect implementation errors in a real-time manner, and help the developers and users of the system to react to the problems before critical failure occurs.     

Software engineering and production monitoring systems

Software that is to be designed and written for operation in the factory environment is especially difficult to conceptualize, design and successfully install. This paper focuses on some aspects of software engineering that apply to this situation and may prove useful to others involved in this profession. The particular problem that is considered in the paper is that of a Real-time Production Monitoring System although any industrial system could have been used. Monitoring industrial processes and displaying meaning ful data in real-time is extremely difficult, mainly because each component, although complementary, is functionally, electrically and temporally quite different. It is therefore difficult to design a standard factory data structure or always to find elegant processing mechanisms. In order to integrate data from these disparate sources, the system must be carefully architected, using consistent and sound software engineering principles.The paper included practical aspects of the implementation of this particular information system, which is a growing component in the management process of a typical computer-integrated manufacturing facility. The paper contains sections on human-factors engineering, fault detection and system recovery. The selection of the operating system platform is critical, and software engineering professionals should appreciate the sections devoted to the system components. Some material is based on the author's own practical experience gained in the design and implementation of several such systems.     

Systems with low distributed simulation overhead

Distributed simulation often involves a large number of overhead messages. This may lead to severe performance degradation of the simulator as pointed out in several previous works. In this work special classes of systems which can be simulated with low overhead-in most systems identified here the total number of overhead messages on any given communication line is at most one, irrespective of the time up to which the physical system is to be simulated-are presented. This includes acyclic systems, some closed queuing networks, some open cyclic queuing networks, and other special types of cyclic networks. Distributed simulation algorithms specially tailored to these systems are given. By isolating these classes of systems and designing distributed simulation algorithms specifically geared for them, a large number of overhead messages can be avoided. By contrast, other distributed simulation algorithms are usually designed for more general systems and they usually require too many overhead messages, even in simulating these special classes of systems     

Unreliable multi-server system with controllable broadcasting service

Consideration was given to the multi-server queuing system with an infinite buffer. The customer arrivals obey a Markov arrival flow, the time of customer service having a phasetype distribution. service may be done with errors. If at the instant of customer arrival the number of busy servers is less than some threshold, then the customer is copied to all free servers which service it. If at that instant the number of busy servers is not less than some threshold, then the customer is serviced by a single server. The stationary distribution of the number of customers and their sojourn time were determined. The impact of the threshold value on the probability of successful service of the customer was studied numerically.     

Closed multiresource queueing systems with controllable priorities

The paper investigates a closed queue model with controllable priorities in which the customers require a random number of channels simultaneously. A technique for aggregation of phase space states is proposed, reducing the dimension of the problem. Numerical examples are presented.Translated from Kibernetika, No. 5, pp. 90–93, September–October, 1989.     

一种视频设备流量监测软件的设计

针对在研的视频数字化设备开发了一种视频流量监测系统。该系统采用微软MFC的API技术设计,通过通信接口接收流量信息,并经信号处理后实时显示视频设备的流量信息。应用结果表明,该监测系统运行稳定可靠,监测精度高,具有一定的实用性和推广价值。     

Optimization of linear systems with controllable coefficients

Consideration was given to the characteristic properties of the linear differential equations with controllable coefficients, their dynamic invariants and constraints on the reachability domain that are important for the problems of control, properties of the Pontryagin extremals of this class, and numerical methods of control optimization.     

A Spark-based Apriori algorithm with reduced shuffle overhead

The Journal of Supercomputing - Mining frequent itemset is considered as a core activity to find association rules from transactional datasets. Among the different well-known approaches to find...     

Traceband: A fast,low overhead and accurate tool for available bandwidth estimation and monitoring

Available bandwidth estimation techniques are being used in network monitoring and management tools to provide information about the utilization of the network and verify the compliance of service level agreements. However, the use of these techniques in other applications and network environments is limited by the long convergence times, accuracy errors, and the amount of overhead that they introduce. In this paper, we introduce Traceband, a hidden Markov model-based technique for end-to-end available bandwidth estimation and monitoring that improves these performance metrics and therefore promises to expand the use of these techniques in other scenarios. Traceband is evaluated and compared with Spruce and Pathload using Poisson and self-similar cross-traffic. Experimental results in a controlled environment with Poisson cross-traffic demonstrate that Traceband is as accurate as Spruce and Pathload but considerably faster, and introduces less overhead. Traceband’s convergence time is demonstrated using bursty cross-traffic, as it is the only tool that accurately reacts to zero-traffic periods, which may be particularly useful for those applications that need to make decisions in real time. Using self-similar traffic, Traceband’s mean accuracy and variability degrade with the Hurst parameter but it still performs within reasonable limits. A general and optional moving average algorithm is also introduced to solve these issues.     

Control of incompletely controllable differential-difference systems with delay

A problem of control of linear autonomous differential-difference systems for violation of the condition of complete controllability and uncontrolled initial state is studied. A problem of system trajectory nullification and its delay there within any specified time period is posed. A new condition for solvability of this problem is proved and a constructive solution is proposed.     

An anticipative scheduling approach with controllable processing times

In practice, machine schedules are usually subject to disruptions which have to be repaired by reactive scheduling decisions. The most popular predictive approach in project management and machine scheduling literature is to leave idle times (time buffers) in schedules in coping with disruptions, i.e. the resources will be under-utilized. Therefore, preparing initial schedules by considering possible disruption times along with rescheduling objectives is critical for the performance of rescheduling decisions. In this paper, we show that if the processing times are controllable then an anticipative approach can be used to form an initial schedule so that the limited capacity of the production resources are utilized more effectively. To illustrate the anticipative scheduling idea, we consider a non-identical parallel machining environment, where processing times can be controlled at a certain compression cost. When there is a disruption during the execution of the initial schedule, a match-up time strategy is utilized such that a repaired schedule has to catch-up initial schedule at some point in future. This requires changing machine–job assignments and processing times for the rest of the schedule which implies increased manufacturing costs. We show that making anticipative job sequencing decisions, based on failure and repair time distributions and flexibility of jobs, one can repair schedules by incurring less manufacturing cost. Our computational results show that the match-up time strategy is very sensitive to initial schedule and the proposed anticipative scheduling algorithm can be very helpful to reduce rescheduling costs.     

基于GPRS的远程心电实时监护仪软件系统设计

针对远程心电实时监护的特殊要求设计的监护仪软件系统,实现了心电实时监护、医嘱短信收发、监护状态显示、紧急求救报警等功能。     

基于互联网的可控业务网体系架构

为了使网络对业务具感知和控制能力,提出了一种基于互联网的可控业务网体系架构--INACOS(Internet based network architecture with controllable service).该架构在现有的互联网承载层之上应用层之下增加一个业务垫层,实现对电信业务共性功能的支持、控制和管理.通过INACOS,可以在不改动互联网承栽设备和协议的情况下,为网络增加对业务的感知和控制能力,从而为用户业务提供较好的服务质量和较高的安全性.最后,通过一个INACOS原型系统,表明了该架构的可行性.     

Job sequencing with uncertain and controllable processing times

In this paper, a single machine scheduling problem is considered. The jobs' processing times are controllable (i.e., they may take any value within a certain range) and non-precisely defined. They are treated as linguistic variables, whose values are expressed by means of fuzzy numbers. The objective function to be minimised is: (a) the mean flow time cost plus the mean processing cost, and (b) the maximum flow time cost plus the total processing cost. The problem is modelled as an assignment problem and is solved optimally with respect to the defuzzification strategy used.     

Low overhead path regeneration

Monte Carlo Path Tracing is a core light transport technique which is used for modern methods (like BDPT, MLT, VCM and others). One of the main challenge of efficient GPU Path Tracing implementation is inefficient workload caused by paths of different lengths; few threads process the long paths, while other threads are idle. A work distribution technique called “Path Regeneration” is commonly used to solve this problem. We introduce a novel GPU implementation of path regeneration technique called “in place block based path regeneration.” In comparison to previous approaches our algorithm possesses two main advantages: it has lower self-cost and it does not move any per-ray data along threads in memory, thus, our algorithm can be easily integrated to any advanced path tracing technique (like BDPT, MLT and other) or photon mapping. We tested our solution with path tracing using both CUDA and OpenCL.     

一种可控分频比分频器的设计与研究

提出了一种具有小数分频比的数字分频设计原理,给出了这种分频器的电路结构和数学模型,对它的抖动性能进行分析,在分频比的纯小数部分的值接近0．75和0．25的情况下,给出了可控分频比分频器电路的改进方法。     

Simultaneously controllable fuzzy matrices

Let F be a set of n × n fuzzy matrices. F is called simultaneously controllable if there exists a permutation matrix P such that for each A ε F, C = [c_ij] = P A P^T satisfies c_ij ≥ c_ji for i > j, where is the max-min composition. In this paper, the necessary and sufficient conditions for a set of n × n fuzzy matrices to be simultaneously controllable will be established. A constructive algorithm which can determine a simultaneously controllable set of n × n fuzzy matrices is presented as well.     

Shape controllable micro-nozzle fabrication

A novel fabrication method involving two-step sequential backside exposures utilizing Fraunhofer diffraction is developed in this work to overcome some of the limitations of the current micro-nozzle fabrication techniques in controlling the shape and the size of micro-nozzles. Shape and size of the fabricated micro-nozzles are compared with simulation results. Micro-nozzles with tip diameters varying from 0 to 158.1 μm and the base diameter varying from 167.2 to 360 μm are fabricated simultaneously side-by-side on the same substrate by varying the total exposure dosage from 3 to 6 J/cm² utilizing multiple backside exposures through designed circular aperture and zone plate masks.     

Electro-osmotically controllable multi-flow microreactor

An adjustable diffusion-based microfluidic reactor is presented here, which is based on electro-osmotic guiding of reagent samples. The device consists of a laminar flow chamber with two separate reagent inlets. The position and the width of the two sample streams in the flow chamber can be controlled individually by changing the flow ratio of three parallel guiding buffer streams. Since electro-osmotic flow (EOF) is used for pumping, no external pumps or other moving parts are needed. The region where the diffusive profiles of the two sample streams overlap is used for the reactions. This overlapping region can be manipulated in a predictable way by adjusting the voltages required to generate the respective electro-osmotic flow. Reaction dynamics inside the microreactor is illustrated with a reactant pair of a fluorescent calcium tracer and a calcium chloride solution. An analytical model, which is an analogue of electrical circuits to EOF, was developed and embedded into the LabView control software, allowing real-time control of the microreactor. This paper describes the simulation, fabrication and experimental characterisation of the device.