周志宏对魏氏组织及马氏体的形成和形貌的早期金相研究

关于铁合金中相变的详尽显微组织方面的早期研究之一是由艾伯特·苏佛教授的学生周志宏（哈佛大学博士，１９２８年）完成的。该项研究描述了铁碳合金中魏氏组织和马氏体的形成，所用合金具有宽的碳含量范围，热处理时采用的冷却速率范围也是宽的。还描述了一种独特的汞浴淬火方法。此研究工作从未完全发表过。本文援引该博士论文中的一些原始显微组织照片和部分原文，并试图用我们现今对于铁合金相变的理解来阐明和重新诠释。文中还包括中国引进现代工业和科学的历史背景，以及周志宏对苏佛教授的个人回忆。     

A study of optimal viewing distance in a parallax barrier 3D display

The optimal viewing distance was proposed as a parameter for designing a parallax barrier 3D display. It can be designed based on simple geometric method and by considering the pitches of image display pixels and parallax barrier, or even including the aperture ratios of the image display pixels and parallax barrier. It can be analyzed by using ray tracing method. By considering the optical refraction index of the cover glass, the angular behavior of the system becomes more realistic; however, the geometric method is difficult to be used. We propose a revised method for estimating the view distance and angular behavior. In this paper, we have demonstrated a designated eye position (DEP) for each view and shown that multiple DEPs make a circular curve around the center of the display. We prove the new concept by comparing the optical ray tracing calculations and optical measurement.     

A kinect-based vocational task prompting system for individuals with cognitive impairments

Difficulties in executing daily living tasks hamper the quality of life of many individuals with cognitive impairments who are otherwise physically mobile. With sufficient and appropriate support on the job, many people with developmental disabilities and cognitive impairments are capable of participating in the world of work to various levels. Kinect is used as assistive technology for individuals with cognitive impairments to achieve the goal of performing task steps independently. In a community-based rehabilitation program under the guidance of three job coaches, a task prompting system called Kinempt was designed to assist four participants involving pre-service food preparation training. The study assessed the effectiveness of Kinempt in terms of precision and recall. A follow-up comparative study then evaluated a baseline method and the system of least prompts against the Kinempt system. Results indicate that for participants with cognitive disabilities, acquisition of job skills may be facilitated by use of Kinempt in conjunction with operant conditioning strategies. Our findings suggest that the image recognition technology may be able to facilitate task prompts needed by people with cognitive impairments. Therefore, the system may be helpful for pre-service training while increasing independence in the process of community integration.     

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Integration of independent component analysis and neural networks for ECG beat classification

In this paper, we propose a scheme to integrate independent component analysis (ICA) and neural networks for electrocardiogram (ECG) beat classification. The ICA is used to decompose ECG signals into weighted sum of basic components that are statistically mutual independent. The projections on these components, together with the RR interval, then constitute a feature vector for the following classifier. Two neural networks, including a probabilistic neural network (PNN) and a back-propagation neural network (BPNN), are employed as classifiers. ECG samples attributing to eight different beat types were sampled from the MIT-BIH arrhythmia database for experiments. The results show high classification accuracy of over 98% with either of the two classifiers. Between them, the PNN shows a slightly better performance than BPNN in terms of accuracy and robustness to the number of ICA-bases. The impressive results prove that the integration of independent component analysis and neural networks, especially PNN, is a promising scheme for the computer-aided diagnosis of heart diseases based on ECG.     

Survey of modular ontology techniques and their applications in the biomedical domain

In the past several years, various ontologies and terminologies such as the Gene Ontology have been developed to enable interoperability across multiple diverse medical information systems. They provide a standard way of representing terms and concepts thereby supporting easy transmission and interpretation of data for various applications. However, with their growing utilization, not only has the number of available ontologies increased considerably, but they are also becoming larger and more complex to manage. Toward this end, a growing body of work is emerging in the area of modular ontologies where the emphasis is on either extracting and managing "modules" of an ontology relevant to a particular application scenario (ontology decomposition) or developing them independently and integrating into a larger ontology (ontology composition). In this paper, we investigate state-of-the-art approaches in modular ontologies focusing on techniques that are based on rigorous logical formalisms as well as well-studied graph theories. We analyze and compare how such approaches can be leveraged in developing tools and applications in the biomedical domain. We conclude by highlighting some of the limitations of the modular ontology formalisms and put forward additional requirements to steer their future development.     

NCTUns tool for wireless vehicular communication network researches

Several goals such as improving road safety and increasing transport efficiency are being pursued in intelligent transportation systems (ITS). Wireless vehicular communication is one technology to achieve these goals. Conducting vehicular experiments on the roads is an approach to studying the effectiveness of wireless vehicular communication. However, such an approach is costly, hard-to-control (repeat), dangerous, and infeasible when many vehicles and people are involved in the field trial. In contrast, the simulation approach does not have these problems. It is a very useful approach and complements the field trial approach. This paper presents NCTUns, an open source integrated simulation platform, for wireless vehicular communication network researches. This tool tightly integrates network and traffic simulations and provides a fast feedback loop between them. Therefore, a simulated vehicle can quickly change its driving behavior such as moving speed and direction when it receives a message from the wireless vehicular communication network. This capability is required by several novel ITS applications such as active collision avoidance systems. In this paper, we present the design, implementation, validation, and performance of this tool.     

Solvent effect on ageing of silica gels

The structure of silica gels derived from tetraethoxysilane (TEOS) with molar compositions of TEOSH₂OHNO₃=1100.4 and then aged in various solvents, was studied. The effect of various solvents having different physical properties on the gel structure, as well as the relationship between the solvent properties and the dried gel structure, were investigated. The density, surface area and pore-size distribution were measured. The results of the pore structure and SEM showed the aged gels to have a slit-shaped micropore, narrow pore-size distribution, and homogeneous microstructure. The density, surface area, pore size and pore volume of dried gels changed as the gels were subjected to ageing in various solvents. The surface area could be related to the polarity parameter of the ageing solvent.     

Process simulation and fabrication of advanced multi-step three-dimensional braided preforms

The fundamentals of multi-step braiding for the fabrication of three-dimensional fibre preforms for composites have been studied. To facilitate the understanding of the complex multi-step braiding processes, a computer simulation algorithm has been developed. The simulation acts as a tool to allow the identification of individual yarn paths, number and location of yarn groups, and braid geometry. It was found that individual control of the rows and columns of yarn carriers on a Cartesian braiding bed allows for the fabrication of advanced multi-step braids; the micro-structural possibilities of three-dimensional braids are thus greatly extended. Some basic relationships of the braiding parameters have been identified. It has been concluded that the traditional four-step and two-step braidings are special cases of multi-step braidings. To verify the feasibility of the structures, experimental investigations have also been carried out. Innovative braid architectures have been designed and fabricated using a prototype multi-step braiding machine.