北京市铁路噪声特性实例分析研究

通过实际测量及数据分析，认为测量现场昼夜等效声级达到 ７７７ ｄ Ｂ（ Ａ），超过了国家标准；快速列车噪声频谱分布复杂，难以治理；列车鸣笛对铁路噪声超标贡献最大，验证了铁路噪声与列车车速的关系，最后提出控制铁路噪声的建议。     

British Shipping and World Competition[1] revisited

The object of my book British Shipping and World Competitionwas to answer the question: 'Why has the tonnage of ships registered in the United Kingdom declined from over 45% of the world total in 1900 to about 16% of that total in 1960?'. There was never any normative element to this question, a point which has been much misunderstood. In answering the question, two different methodologies were used. Chapters II through VIII are industrial economic history, whereas Chapters IX through XIV are applied economics. When the two groups are thought of as siblings, not as Siamese twins, it can be seen that the first group has worn rather well, but that the applied economics chapters have a distinctly dated air. Most of this article is concerned with the applied economics chapters, where I try to examine what is said in the book in the light of my subsequent experience and thinking. There is one absolutely gross error in the material. Unfortunately, this is implicitly reflected in the Code of Conduct and in the EC Maritime Regulations. The original answer to the question has been rephrased in the article; I hope this will put to rest the idea that the question was normative in intent. The rephrasing does not alter the answer: the decline which needed to be accounted for can be explained solely in terms of internal constraints. The remainder was a 'natural' result of changing international patterns in resource allocation.     

Prediction of ship brittle fracture casualty rates by a probabilistic method

It has been proposed that grade A should be replaced with a tougher steel for ship construction. This recommendation is not supported by casualty statistics. Brittle fractures have decreased from once every 10 ship years at the time of the Liberty ships, to once every 100 ship years in the 1950s, and now stand at around once every 10,000 ship years. The authors have developed a probabilistic fracture mechanics approach indexed to the Charpy 27 Joule temperature, T_27J. This is used here to analyse the Liberty ship failures. Comparison with a databank of T_27J values for grade A steel spanning 1920 to 1995 suggests that the Liberty ship steel was unusually brittle. The probability analysis shows good agreement between predicted and observed fracture casualty rates for the Liberty ships and helps explain why brittle fractures are now uncommon in grade A steel ships.     

Educational technology: Enhancing port training

Continued improvements in educational technologies using CD-ROM and the Internet can enhance student learning in both a face-to-face mode and delivery at a distance. This paper considers the development and use of enhanced educational technologies for port training and education, both within the classroom and at a distance.     

The social psychological consequence of a life at sea: A causal model

This paper explores the influence of this occupation on alienation and social integration of its members. Data were collected using a survey instrument from a sample of 293 seamen, both officers and crew. Factors determining variance in levels of alienation are examined using multiple regression technique. Results indicate that variance in several occupational features of life at sea affect the degree of alienation experienced by seamen, and a number of social characteristics were found to mitigate these influences. Supplementary qualitative data are also used.     

无舱盖集装箱船货舱强度研究

无盖集装箱船在货舱满载工况下的货舱强度是这种新型船舶结构设计的关键，本文通过１０００箱无舱盖集装箱船货舱强度的研究表明，只要考虑到这种船舶的受力特点，通过精心设计计算，无舱盖集装箱船的货舱结构是能满足强度要求的。就结构而言，设计和制造这种无舱盖集装箱无特别的困难。     

Multidisciplinary marine environmental database for the Aral Sea

Special unique database management and processing system (Oceanbase) have been developed to work with the large sets of multivariable interdisciplinary oceanographic and environmental data. AralBase system developed to work with the Aral Sea interdisciplinary data is a variety of the OceanBase. AralBase is a special database application with the expanded functionality designed to explore large multidisciplinary oceanographic and environmental data sets. It provides many possibilities for data loading, selection, access, processing, analysis, preview and export. The AralBase has a customizing user-friendly multi-windows interface. A user can create his/her own desktops and open and arrange as many windows as he/she needs.The most valuable feature of AralBase is the integration of many service tools that allow the user to carry out almost all data processing without any additional software. At the moment, the database is loaded with the oceanographic and meteorological data provided by the participants of the Inco-Copernicus Aral-Kum Project.The OceanBase system and the AralBase, in particular, are the very flexible systems, and they can be used in any environmental and oceanographic project or institution dealing with the water environment (ocean, lakes, rivers) data. The preloaded data bases with the Data Explorer system module can be distributed among the interested scientists and experts to simplify drastically their work with data.     

Automotive Steering Control in a Split-µ Manoeuvre Using an Observer-Based Sliding Mode Controller

Summary In this paper a sliding mode integral action controller and sliding mode observer are used to enhance vehicle stability in a split- µ manoeuvre. Anti-lock braking systems (ABS) have become an integral part of modern cars, and they have dramatically improved vehicle handling in braking manoeuvres. However, when a vehicle attempts to brake on a surface with uneven friction coefficient such as on wet or icy roads, a so-called split- µ scenario, the yaw moment generated by the asymmetric braking can prove demanding for an inexperienced driver. The controller presented hereworks in conjunction with a conventional ABS system to provide safe and effective braking through steer-by-wire. This paper extends previous state-feedback work by only using certain measurable quantities in the controller, estimating further signals by employing an observer.