Non-response in student surveys: The Role of Demographics,Engagement and Personality

What causes a student to participate in a survey? This paper looks at participation across multiple surveys to understand survey non-response; by using multiple surveys we minimize the impact of survey salience. Students at a selective liberal arts college were administered four different surveys throughout the 2002–2003 academic year, and we use the number of surveys participated in to understand how student characteristics such as demographics, engagement and Holland personality type affect cooperation. We find that survey respondents are more likely to be female and socially engaged, less likely to be on financial aid, more likely to be an investigative personality type and less likely to be an enterprising personality type.     

System design and analysis of the trans-critical carbon-dioxide automotive air-conditioning system

As an environmentally harmless and feasible alternate refrigerant, CO₂ has attracted worldwide attention, especially in the area of automobile air-conditioning (AAC). The thermal property of CO₂ and its trans-critical refrigeration cycle is very different from that of the traditional CFC or HCFC system. The detailed process of CO₂ system thermal cycle design and optimization is described in this paper. System prototype and performance test bench were developed to analyze the performance of the CO₂ AAC system.     

Who Needs a Terrestrial Signal? Internet Audio Streams Make Waves in Two Kansas Radio Markets

Among American audio listening options is live streaming, and it is becoming a major component in the competitive local and national marketplace. While “playlist generators” like Spotify and Pandora have been well covered, little attention has been given to individual entrepreneurs who are using streaming as a means of attracting audiences and advertising dollars. This comparative case study provides a contrast in the business models used by two former broadcasters who are using streams in lieu of terrestrial radio signals to compete in two Kansas markets.     

An efficient method for parallel CRC automatic generation

The State Transition Equation (STE) based method to automatically generate the parallel CRC circuits for any generator polynomial or required amount of parallelism is presented. The parallel CRC circuit so generated is partially optimized before being fed to synthesis tools and works properly in our LAN transceiver. Compared with the cascading method, the proposed method gives better timing results and significantly reduces the synthesis time, in particular. Project (No. 60271010) supported by the National Natural Science Foundation of China     

Retrieval,visualization, and mining of large radiation dosage data

Radiation dose monitoring has become an essential service that hospitals must perform. Depending on the system in place, this can result in the collection of large quantities of data, ripe for analysis. These data should include a wide variety of variables for each study because assessment of the propriety of the patient’s dose is dependent on many factors, including patient age and size, as well as the body section that is being scanned. Moreover, the scanners themselves have many properties that affect patient dose, such as model, pitch and kVp. In this paper, we propose an engine that seamlessly integrated with a clinical PACS to retrieve radiation dosage data. We devised several schemes to analyze these data through visualization and mining techniques that examine it at different scopes. We demonstrate the utility of such visual methods at examining large, noisy, and multi-dimensional data, which is embodied in the collected radiation data.     

Location refinement and power coverage analysis based on distributed antenna

To establish wireless channel suitable for the cabin environment, the power coverage was investigated with distributed antenna system and centralized antenna system based on the actual measurement of channel impulse response. The results indicated that the distributed antenna system has more uniform power coverage than the centralized antenna system. The average relative errors of receiving power of both antennas were calculated. The optimal position of the centralized antenna was obtained by Gaussian function refinement, making the system achieve a better transmission power with the same coverage effect, and providing a reference for antenna location in the future real communication in the cabin.     

Pressure angle in parallel mechanisms: From planar to spatial

This paper presents the evolution process of pressure angles from planar parallel mechanisms to spatial parallel mechanisms. Manipulability and condition number, which are frequently used in the optimum design of parallel mechanisms, are introduced from serial robots at first. Then, both theoretical analysis and practical experiences demonstrate that these concepts seem imperfect when they are used in parallel mechanisms. For this reason, this paper introduces the pressure angles in planar 4-bar mechanisms to spatial parallel mechanisms, which include redundant parallel mechanisms. Two kinds of pressure angles extracted from the determinant of direct and indirect Jacobian matrices are investigated. Moreover, two comprehensive and visible global performance indices are defined, showing the advantages in evaluating the workspace, singularity and motion/force transmission capabilities. With a 2-DOF planar and a 3-DOF spatial parallel mechanism as examples, the application of the performance indices is investigated and compared with the condition number at last. The proposed concept can be extended to other spatial parallel mechanisms.     

英语语法研究与大学英语教学

英语语法研究大体经历了从借鉴到描写到解释三个阶段。通过对早期规定语法、描写语法、转换 -生成语法和系统功能语法的历史演变与发展过程的分析和阐述 ,以说明在现代语法研究和我国英语教学中应把语法运用放在首位 ,培养学生在交际活动和与自然语言接触中运用语法规则的能力     

标记系统及学术文本处理的未来（二）

标记事务影响着学者们对思考与写作系统的采纳使用。程序性标记和表示性标记会阻碍这一进程的发展,描述性标记则通过简化机械性任务,让学者们将注意力集中于内容上的做法,以加快这一进程。