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201.
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.  相似文献   
202.
This paper mainly focuses on the accurate estimation of the torque transferred through the engine clutch installed between the engine and the drive motor in parallel-type hybrid electric vehicles. The estimation of the engine clutch torque primarily relies on the forward-direction observer which uses the nominal engine net torque information. To overcome the limitation of using the nominal engine torque information that it may not be accurate during the transient states or due to the influence of external disturbance such as the road condition and wind, the forward-direction observer is supplemented by the use of reverse-direction observer which uses the driveline model and wheel speed measurements. In addition, the drive motor torque information is used to calibrate the nominal engine torque during the idle charging state, so that the driveline characteristic unique to parallel-type hybrid electric vehicle can be utilized to increase the estimation accuracy. Finally, the estimation performance of the designed observer is tested via simulation and experiments based on a real vehicle.  相似文献   
203.
The Princeton Ocean Model (POM) has been used to investigate the wind-driven circulation in the stratified long and narrow Gulf of Elat (Aqaba). Our results indicate that the circulation consists of a series of gyres aligned along the main axis of the basin, and that their size and location are strongly affected by the shoreline and, to a lesser extent, by the hydrography. The seasonality in both the flow and the free surface height (FSH) at any specific station are caused mainly by the strong seasonality in the hydrography — the FSH and the magnitude of the currents above the thermocline are inversely related to the thickness of the upper layer. The seasonality in the flow is also manifested in the location and diameter of the gyres. This seasonal change in the gyres' diameter and location might provide an explanation for the current reversal observed at the northern tip of the western boundary during the month of February.  相似文献   
204.
This two‐part paper contains most of a report prepared by TRRL for the European Conference of Ministers of Transport, and presented by one of the authors to the Council of Ministers in November 1984. Part 1, which was published in the January‐March 1986 issue of Transport Reviews, looked at the way cities have been changing over the years and the influence of growing car ownership on trip patterns. This part examines the changes in public transport use in more detail, considers the interactions between the various underlying trends, speculates on future travel patterns by both public and private means and considers the likely impact of land use and transport policies.  相似文献   
205.
Passenger Transport: Planning for Radical Change. Edited by J. D. Carr. (Gower: Aldershot.) [Pp. 224.] £27.50. ISBN 0 566 05183 4.

Geografia Transportu Polski. Transport Geography of Poland (in Polish). Second edition. By T. Lijewski. (Panstwowe Wydawnictwo Ekonomiczne, 1986.) [Pp. 286.] Z1.240. ISBN 83 208 0474 4.

Future Transport Policy. By K. J. Button and D. Gillingwater. (London: Croom Helm, 1986.) [Pp. 224.] £27.50. ISBN 0 7099 3225 1.  相似文献   
206.
While transport infrastructure investments have usually been viewed to have long-term impacts on employment, what is perhaps not immediately clear is the direction of causality. This paper has sought to disentangle the causal relationship between highway infrastructure and employment, using panel data for the 48 contiguous US states from 1984 to 1997. Of particular emphasis in this analysis is the sectoral differences in the causal and spatial effects of highway capacity expansions for employment growth in alternative sectors of the economy. The results indicate that lane-mile additions of own-state major highways could increase state employment growth in the services sector while reducing growth in manufacturing. However, the causal relationship is also found to work the other way around. That is, both the rapid growth in services employment and the slowdown in manufacturing jobs temporally lead to increases in roadway capacity of non-interstate major roads. Our analysis also shows that highway infrastructure could produce both positive and negative employment spillovers across states. We find that improvements in non-interstate major roads outside the state border are beneficial to the manufacturing sector which generally serves regional and national markets. For the services sector, however, employment gains from interstate highways in the same state may come at the expense of other states as there is clear evidence of negative employment spillovers from interstate lane-mile additions.  相似文献   
207.
An integrated approach is suggested for the planning and evaluation of mass transport systems which includes a bus network and LRT/RTS in urban areas. This approach involves a simplified procedure for determining mass transit demand, bus route network generation and evaluation, light or rapid transit corridor identification and its patronage determination in the presence of bus networks. Scheduling of a mass transportation system based on marginal ridership concept is also suggested for a given fleet size. All the three major components (demand estimation, route network generation and scheduling) iterate and interact each other with a feedback mechanism for the desired optimal solution in terms of performance indicators. Necessary interactive software packages for all the above subsystems have been developed.  相似文献   
208.
Performance analysis of a CVT clutch system for a hybrid electric vehicle   总被引:1,自引:0,他引:1  
In this study, the performance of a CVT clutch system for a hybrid electric vehicle was investigated. To analyzed the vehicle performance at restart, the restart delay and driveshaft torque was investigated by simulations and experiments. It was found from the simulation results that the vehicle restart response depends on the clutch pressure buildup time to the point where the clutch torque begins to overcome the vehicle road load, and driving comfort at restart is directly related to the rate change of the clutch pressure.  相似文献   
209.

Graphics are a powerful but often costly means of communication. Computer‐drawn graphics offer a new and relatively inexpensive way to assist the communication of complex technical information to both planners and non‐technical people whose full potential is now beginning to be realized. This paper discusses the utility of graphics and introduces three computer‐drawn graphic techniques which may be useful, both for analysis and presentation of results, in the transportation planning process. CENVUE(S) produces a three‐dimensional, perspective‐view map, on which virtually any type of transportation data or performance indicator can be displayed. VAP is designed to display origin‐destination travel patterns in any region. TDN transforms a physical‐distance network into a time‐distance network so that effects of different speeds in the transportation network can be readily seen. The cost‐effectiveness of each technique is briefly discussed and some recommendations for evaluating computer graphics techniques are provided to aid the user in further assessing their utility in the transportation planning process.  相似文献   
210.
针对传统算法在解决多项式的因式分解过程中,存在着只适用于精确分解而不适合系数为浮点数的多项式的因式分解问题,文中提出一种应用双种群双突变进化策略来对浮点数多项式近似分解的算法,克服了传统算法不能解决浮点数多项式的因式分解的弊端.数值计算结果表明该算法收敛速度快、精度高、稳定性强.  相似文献   
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