Virtual Sample Processing: Extending the Reach of Multimedia

Traditional multimedia systems deal with only a few basic media: text, graphics, audio and video. However, many other types of media, such as ultrasound, infrared and RF signals, can be represented by streams of data samples and processed within multimedia applications. In this paper, we introduce some of these new media domains and identify interesting opportunities enabled by their software-based processing. We also describe our SpectrumWare testbed for experimenting with these new media types and report on our experience to date.We believe that the time has come to broaden the scope of multimedia to include any form of sampled information. Advances in processor and analog-to-digital conversion technology have brought raw sample streams within the grasp of desktop computers and media processing systems. Coupling these new media types with software-based processing allows the construction of virtual devices that can handle different sample sources, modify their behavior based on information extracted from the media, and transform information between media domains.     

探究在教学中运用的多媒体技术及其特性

计算机多媒体技术与教学的结合使得教学有了突飞猛进的发展。为了激发学生学习兴趣,提高教学效率,以及满足当前教学的需求,计算机的多项技术在教学中发挥着重要作用。通过介绍多媒体技术的相关特性,多媒体的常用数据准备软件和视频点播,结合教育技术学中的理论,阐述多媒体技术在教育领域中所发挥的作用。详细介绍了几种常用数据准备软件。说明了在教学中多媒体技术的重要性。     

JASMINE: A Java Tool for Multimedia Collaboration on the Internet

Although collaboration tools have existed for a long time [8], Internet-based multimedia collaboration has recently received a lot of attention mainly due to easy accessibility of the Internet by ordinary users. The Java platform and programming language has also introduced yet another level of easy access: platform-independent computing. As a result, it is very attractive to use Java to design multimedia collaboration systems for the Internet. Today there are many systems, which use Java for multimedia collaboration. However, most of these systems require the shared Java application to be re-written according to the collaboration system's Application Programming Interface (API)—a task which is sometimes difficult or even impossible. In this paper, we describe a practical approach for transparent collaboration with Java. Our approach is transparent in that the Java application can be shared as is with no modifications. The main idea behind our system is that user events occurring through the interactions with the application can be caught, distributed, and reconstructed, hence allowing Java applications to be shared transparently. Our architecture allows us to make the huge installed base of Java applications collaborative, without any modification to their original code. We also prove the feasibility of our architecture by implementation of the JASMINE¹ prototype.     

单向ad—hoc移动网络路由协议UAOR

单向ad-hoc移动网络是一种完全由移动主机构成的网络,传统的路由协议由于基于DBF方式其路由更新开销大,对网络拓扑结构改变收敛慢,不适合ad-hoc移动网络拓扑变化快和带宽有限等特点。文中提出了一种支持单向ad-hoc移动网络的路由协议UAOR,它采用按需方式查找路由,并根据主机之间的邻接关系和距离矢量来选择相对最稳定且最短的路由,具有路由更新开销小,快速适应网络拓扑结构改变等特点。     

从一支粉笔到多媒体教学——谈多媒体教学在电学课上的有效应用

该文就多媒体技术在电学课教学中的有效应用进行了简单的探讨。多媒体技术的应用给枯燥的课堂增添了活力,它在教学中不仅有利于教学情境,调动学生学习兴趣,还节省了课堂教学时间,同时充分利用多媒体技术提高了学生电工课上的动手操作能力,还开阔了视野,推进学生素质教育的进步。     

建立大学生网上学术论坛的初步探讨

本文首先从结构设计和内容设计两个方面论述了大学生网上学术论坛的基本构架,重点介绍了网上学术论坛的内容设计,包括以下四个部分:课堂教学栏、课外研究和学术动态栏、论坛管理和布告栏以及下载栏等,最后对网上学术论坛的优点进行了阐述.     

Experimental Assessment of the Period Calibration Method: A Case Study

In this paper we present an experimental evaluation of the period calibration method (PCM) which was developed in Gerber et al. (1994, 1995) as a systematic design methodology for real-time systems. The objective of this experimental study is to assess design alternatives integrated into the method and their performance implication on resultant systems built via the PCM. Such design alternatives include scheduling jitter, sensor-to-output latency, intertask communication schemes, and system utilization. For this study, we have chosen a computerized numerical control (CNC) machine as our target real-time system, and built a realistic controller and a plant simulator. We show the detailed development process of the CNC controller and report its performance. The performance results were extracted from a controlled series of more than hundred test controllers obtained by varying four test variables. This study unveils several weaknesses of the PCM: (1) the communication scheme built into PCM incurs a large latency though average sensor-to-output latency is one of the most dominating factors in determining control quality; (2) scheduling jitter is taken seriously in PCM though its effect appears only when average sensor-to-output latency is sufficiently small; (3) loop processing periods are not properly optimized for control quality though they are another dominating factor of performance; and (4) transient overloads are not considered at all in PCM, even though they can seriously damage the performance of a system. Based on these results, we propose a new communication scheme and a transient overload handling technique for the improved period calibration method.     

A Case Study: Management and Exploitation of the Nuclear Decommissioning Agency Geoscience Data Archive

The British Geological Survey (BGS) is responsible for managing a major geoscience data archive on behalf of the UK Nuclear Decommissioning Authority (NDA). Much of this geological data was captured during the 1990s and early 2000s using now obsolete software and data formats. This data asset remains an important resource for the NDA and the wider scientific community. The NDA wishes to ensure the data remain accessible and usable for many decades into the future. BGS has been working closely with Radioactive Waste Management (RWM), a wholly owned subsidiary of the NDA, on a program of data management and digital continuity measures to ensure the long-term usability of the data. This article describes some of the challenges and outlines the approaches we have taken to address these issues.     

基于情感分析的“真假美猴王”存疑研究

《西游记》是我国四大名著之一。“真假美猴王”事件作为《西游记》的高潮部分,留下了不少伏笔,也引发了多种解读。该文通过运用情感分析的方法,对“真假美猴王”事件前后孙悟空与其他角色的对话进行分析。通过比较孙悟空在“真假美猴王”事件前后,对其他角色情感值的变化,得到了“孙悟空并没有被如来打死,‘真假美猴王’事件消灭的‘心魔’是孙悟空的反抗精神。事件之后,孙悟空选择屈服于神权”的结论。初步探索了情感分析技术对文学研究的可行性。     

Extending an ICT4D Computer Re-use Model with E-waste Handling Activities: A Case Study

This paper illustrates how a computer re-use model can be extended to deal with e-waste challenges. First, we describe the re-use of computers as a factor that can help bridge the global digital divide. In an ICT4D context, refurbished computers can be used in developing countries. We describe and illustrate the operating model of such a computer re-use organization, highlighting the different components and interactions of the operating model. Next, we discuss how e-waste puts this computer re-use model under pressure. We argue that the sustainability of computer re-use in an ICT4D context is seriously impacted by this increasing e-waste problem. Finally, we describe how a computer re-use model can be extended and complemented with e-waste handling activities to retain positive effects in an ICT4D context. The paper is based on a single case study.     

Improving the Quality of Web-based Enterprise Applications with Extended Static Checking: A Case Study

ESC/Java2 is a tool that statically detects errors in Java programs and that uses the Java Modeling Language (JML) as its annotation language. ESC/Java2 can modularly reason about the code of a Java Web-based Enterprise Application (WEA) and uncover potential errors. In this paper, we assessed the effectiveness of ESC/Java2 at helping developers increase WEA quality by detecting design and implementation issues.     

Applying an Agent-Oriented Methodology to the Design of Artificial Organizations: A Case Study in Robotic Soccer

The multi-agent paradigm is widely used to provide solutions to a number of organizational problems related to the collective achievement of one or more tasks. All these problems share a common difficulty of design: how to proceed from the global specification of a collective task to the specification of the local behaviors to be provided to the agents? We have defined the Cassiopeia method whose specificity is to articulate the design of a multi-agent system around the notion of organization. This paper reports the use of this method for designing and implementing the organization of a soccer-playing robotic team. We show why we chose this application and how we designed it, and we discuss its interest and inherent difficulties in order to clearly express the needs for a design methodology dedicated to DAI.     

Interfacing Oz with the PCTE OMS: A Case Study of Integrating a Legacy System with a Standard Object Management System

The integration of a legacy system and a standard Object Management System (OMS) is often a very challenging task. This paper details a case study, our experiment in interfacing Oz with the PCTE (Portable Common Tool Environment) Object Management System. Oz is a multi-user process-centered software development environment that has been under development in our lab since 1987, originally under the name Marvel. PCTE is a specification that defines a language-independent interface providing support mechanisms for software engineering environments (SEE). One of the premises of PCTE is that, in theory, an SEE such as Oz can be built (or extended) using the services provided by PCTE. The purpose of our experiment was to study how a legacy system such as Oz can be integrated into a new environment framework, e.g., PCTE. The architecture of the legacy system and the services of the framework are the key factors in the integration approach. Because Oz historically has included a native OMS, our experiment focused on modifying Oz to use the PCTE OMS, which has an open and standard API. This paper describes how several Oz components were changed to interface to the PCTE OMS. The resulting proof-of-concept hybrid system has process control and integration services provided by Oz, and data integration services provided in part by PCTE. We discuss in depth the solutions to the concurrency control problems that arise in such an environment, where Oz and PCTE use different approaches to transaction management (i.e., each has its own transaction manager). The PCTE implementation used in our experiment was the Emeraude PCTE V 12.5.1, and the Oz version was V 1.0.1.     

融合FY-3C号和FY-4A号卫星数据的积雪面积变化研究—以祁连山区为例

祁连山区积雪类型丰富、判识复杂,是中国积雪研究的典型区域。因此,精确地监测祁连山区积雪面积变化及其时空演变,对祁连山区生态环境和社会经济发展等具有重要意义。FY-3C MULSS利用多阈值积雪指数模型提供全球日积雪覆盖产品,FY-4A AGRI传感器每15~60 min提供一景覆盖全球的多光谱影像。基于FY-4A AGRI高时间分辨率的特征,构建适合于FY-4A号数据的动态多阈值多时相云隙间积雪识别方法,很大程度上减小了云对光学数据识别积雪造成的影响,并结合FY-3C MULSS积雪覆盖日产品较高空间分辨率的优势,融合得到去除云后的FY3C4积雪覆盖数据。利用Landsat 8 OLI卫星数据对融合后的积雪数据进行对比验证,结果表明融合FY-3C和FY-4A后的数据能更好地判识祁连山区的积雪覆盖情况。以MODIS MOD10A2积雪产品为真实值,随机检验了2018年3月~2019年3月融合后数据的积雪判识精度,发现无云情况下方法的总体精度可达到85.25%。进一步研究发现祁连山区积雪面积在海拔、气候和坡向等因素的影响下时空分布极不均匀,总体呈现出冬春季节大于夏秋季节,以及东部积雪面积大于西部积雪面积的特征。     

Fun with FireWire: A Comparative Study of Formal Verification Methods Applied to the IEEE 1394 Root Contention Protocol

Formal Aspects of Computing - The IEEE 1394 Root Contention Protocol is an industrial leader election algorithm for two processes in which probability, real time and parameters play an important...