The World Trade Center Disaster and the Lessons Learned

For NYNEX, the lessons learned from the explosion and fire in the World Trade Center were both positive and negative.     

RASSP Methodology Evaluation and Lessons Learned Developing IRST Signal Processor

The development of a real-time infrared search and track (IRST) processing system served as a real-world test of progress toward the fourfold reduction in cycle time expected at the end of the four-year Rapid Prototyping of Application Specific Signal Processors (RASSP) program. This signal processor development tested the effectiveness of the RASSP methodology and processes and provided critical metrics to evaluate the 4X roadmap. Virtual Prototyping, a VHDL technique for validating hardware and software design before building hardware, makes the RASSP top-down methodology unique. This paper describes the 4X roadmap for cycle time improvement, our experiences with virtual prototyping and important lessons learned for improving the methodology.     

Communications Middleware for Tactical Environments: Observations, Experiences, and Lessons Learned

Tactical networking environments present significant challenges that must be overcome in order to effectively support net-centric warfare. The wireless and ad hoc nature of these networks implies unreliable connectivity, limited bandwidth, and variable latency. Past and current research has focused on physical and data link layers, routing protocols, transport protocols, and cross-layer aspects. However, significant work is needed at the upper layers to better support application requirements. In our experience, achieving effective communications in tactical environments requires taking into account application requirements and communication patterns, designing a rich interface between the application and communication layers, and realizing a communications middleware specifically adapted to tactical networks. In this article, we report on our observations from several tactical networking experiments and demonstrations and the lessons learned from deployment of the Mockets middleware to support tactical communications. We hope these experiences are useful to others designing and implementing applications and systems for tactical environments.     

Designing Pre-College Engineering Curricula and Technology: Lessons Learned From the Infinity Project

The importance of mathematics and science education in today's modern, technology-driven society cannot be understated. This paper describes the history of and ongoing efforts in curricular and educational technology development for the infinity project, a joint effort between educators, administrators, and industry leaders to establish an engineering curriculum at the high school level. Several issues are considered, including the choice and design of the technology platform used in the curriculum, the curricular and technology development timeline, and the design examples chosen to illuminate important engineering concepts within the curriculum. We also provide a list of key best practices and challenges in developing novel pre-college engineering curricula for future engineers.     

欧盟“三网融合”的监管及启示

随着信息技术的飞速发展、电信市场的逐步开放以及用户对多种业务需求的与日俱增,国际上出现了“三网融合”的潮流,即原先独立设计分开运营的传统电信网、计算机网和有线电视网正通过各种方式趋向于相互渗透和融合。三类不同的业务、市场和产业链也在相互渗透和融合。相应地,电     

Model-Based Systems Engineering: Lessons Learned from the Joint Tactical Radio System

The Joint Tactical Radio System was the first major program that sought to develop a new family of radio systems using a software-based architecture. A new software-oriented architecture, the Software Communications Architecture was developed as a common, interoperable foundation for this new family of tactical radios. The fundamental objective was to enable radio systems to support multiple waveforms, allow for software-only upgrades of operational capabilities and ultimately reduce the tail-end logistics, maintenance and upgrade costs. However, within the first few years the program experienced difficulties and setbacks resulting in cost and schedule overruns. Several program reviews and analyses were performed to assess the reasons for the problems encountered. Although multiple causes were cited for the failures, this paper puts forth the assertion that a key aspect of the engineering process, systems engineering, was not planned into the program and a fundamental cause for many of the issues encountered.     

Introducing the Adaptive-QoS Idea into Multi-Tier UMTS Systems: The Lessons Learned

In an integrated terrestrial-satellite system exploiting W-CDMA air interfaces, such as the future UMTS, we conduct an in-depth research on radio resource management techniques for the support of multimedia applications with quality guarantees. The multi-bearer transmission coupled with a multitier coverage has the potentiality of allowing the effective exploitation of the radio resources while guaranteeing an adaptive quality to all end-users. Nevertheless, it still remains to be clearly understood how good they cope with typical features of next-generation multimedia cellular systems, such as soft handoff. This paper tries to contribute to this issue by reporting the lessons learned during a performance assessment study on a simulation platform of a UMTS system. This revised version was published online in July 2006 with corrections to the Cover Date.     

Analyzing Schedule Delay of Mega Project: Lessons Learned From Korea Train Express

In 2004, Korea became the fifth country in the world to own and operate a high-speed railway called Korea Train eXpress (KTX). Numerous uncertainties and challenges during planning and managing phase resulted in schedule delays and cost overruns. The delay causes of each activity along the 412 km Korea high-speed railway route were very difficult to identify because KTX project consisted of 11 141 different activities. This paper evaluates challenges, obstacles, and performances of KTX project. First, critical sections in the railway route that influenced significant delays to project completion were identified. Then, delay causes of these critical sections were investigated thoroughly. The analysis discovered five major delay causes for KTX project. They are lack of owner's abilities and strategies to manage hi-tech oriented mega project; frequent changes of routes triggered by conflicts between public agencies and growing public resistance from environmental concerns; the inappropriate project delivery system; a lack of proper scheduling tool tailored for a linear mega project; and redesign and change orders of main structures and tunnels for high-speed railway, which is fundamentally different from the traditional railway construction. Based on the in-depth analysis of KTX project, through which a conceptual framework was established to identify the various facets of mega projects, this paper suggests lessons learned for engineers to better prepare and respond to potential causes of schedule delays for mega projects.     

Lessons Learned from an Extensive Spectrum Occupancy Measurement Campaign and a Stochastic Duty Cycle Model

Several measurement campaigns have shown that numerous spectrum bands are vacant although licenses have been issued by the regulatory agencies. Dynamic spectrum access (DSA) has been proposed in order to alleviate this problem and increase the spectral utilization. In this paper we present our spectrum measurement setup and discuss lessons learned during our measurement activities. We compare measurement results gathered at three locations and show differences in the background noise processes. Additionally, we introduce a new model for the duty cycle distribution that has multiple applications in the DSA research. We point out that fully loaded and completely vacant channels should be modelled explicitly and discuss the impact of duty cycle correlation in the frequency domain. Finally, we evaluate the efficiency of an adaptive spectrum sensing process as an example for applications of the introduced model.     

“高电压技术”课程线上线下混合式教学

本文采用超星学习通线上教学平台，以 “高电压技术”课程为对象，实施了规模为120余人的线上线下混合式教学。基于线上教学和传统教学的优势互补，设计了“高电压技术”多个教学环节。归纳分析了混合式教学在各个教学环节取得的效果和问题，并根据学生反馈提出了持续性的改进措施。     

网络教学模式下"电工电子"实验教学探索

实验教学是"电工电子"教学的关键组成部分,是提高学生的动手能力,培养学生的创新思维的有效途径.在课堂授课条件不具备的情况下,"电工电子"实验只能通过网络授课的方式完成教学任务.文章给出了"电工电子"网络实验教学的平台搭建方法,将创新理念融入整个实验的教学实施过程.     

线上线下混合教学在高职高专院校教学中的应用

近年来,随着互联网技术的不断发展,教育方面越来越重视发挥线上教学的作用。线上教学突破了空间和时间的限制,帮助学生进行科学合理的知识学习和复习,逐渐缩小不同地区教育资源的差异。对于高职高专院校来说,线上线下混合教学的方式能促进综合能力更加明显的人才。在互联网时代背景下,对高职高专院校推行线上线下混合教学模式进行分析。     

“通信电子线路”课程线上教学设计与实践

面对“新冠病毒”疫情大规模蔓延，在教育部“停课不停学”的倡导下，“通信电子线路”课程组针对课程实际情况，在中国大学MOOC平台下建立了异步SPOC课程，并结合“慕课堂”及“钉钉”直播，在教学设计、教学组织等方面进行了线上教学的实践，制定了一套新的教与学的平衡模式，实现信息技术时代下传统教学形态向新型教学形态的转变。     

新形态教材对“电工电子”混合式教学的影响

电工电子立体化新型态教材体系构建的目标在于通过激发兴趣、引导学习、开展电工电子教学,以及实验教学,以全面提升大学生电工电子理论知识的学习能力,强化实践动手和创新思维。随着互联网、信息技术的发展,电工电子教学的呈现形式不再拘泥传统纸质书,而是以国家精品在线开放课程、数字课程、新型态教材形式出现,这将有助于开展以学生为中心线上线下混合式教学改革。     

多场景互动线上教学课程的设计与实践

在新冠肺炎疫情的特殊时期，“电气工程概论”课程开展多场景（SPOC专题讨论、慕课堂设计、腾讯会议串讲解答、调查问卷等）互动线上教学的设计与实践，着力解决线上教学的互动效果不好的关键问题，努力培养学生自主学习能力，提高学生专业技能，激发学生专业兴趣，保证教学质量。同时也为今后学生返校后开展线上、线下混合教学奠定基础。     

讲授二端口网络的时机和方法

介绍清华大学电路原理课程在教学改革过程中,提出的有关二端口网络讲授时机和方法的一种新的处理思路。二端口网络在电路原理课程中一般放在最后部分进行讲授,因此学生很难将二端口网络融入电路原理的教学内容,造成的后果是这部分内容普遍教学效果不好。本文提出的处理思路是将二端口网络讲授提前,并且在整个电路原理教学过程中从认知规律出发不断展现二端口网络的相应内容,弥补了传统处理方式的缺陷,提高了教学质量。     

Improving the Effectiveness of Virtual Teams: A Comparison of Video-Conferencing and Face-to-Face Communication in China

As virtual teams become more and more important in organizations, understanding how to improve virtual team relational development and meeting outcomes is vital to project success. The objective of this study was to investigate how the dialogue technique that facilitated building of shared understanding in virtual teams can be used to enhance virtual team relational development and decision outcomes in a Chinese cultural context. The results from an experiment demonstrate that the adopted dialogue technique can indeed help team members develop their team relations and enhance their perceived team meeting outcomes. Video-conferencing virtual teams with shared mental models may be engaged as effectively as traditional face-to-face teams. Moreover, this study reveals that the dialogue technique can enhance face-to-face team outcomes. Therefore, the findings of this study have both theoretical and practical implications for helping teams develop shared understanding of effective communication and enhance decision-making outcomes in the Chinese cultural context.