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21.
The research performed in this paper was carried out to investigate the computational procedure to design seakeeping optimized ship hull form. To reach the optimized hull form, four stages should be done, which consists of: generate alternative hull form, seakeeping calculations, objective functions and optimization techniques. There are many parameters that may be determined in ship hull form optimization. This paper deals with developed strip theory for determining the seakeeping performance, genetic algorithm(GA) as optimization method, high order equations for curve fitting of the hull form and finally reaching to the minimum bow vertical motion in regular head waves. The Wigley hull is selected as an initial hull and carried to be optimized. Two cases are considered. For the first case, the only form coefficients of the hull(C B, C M, C W, C P) are changed and main dimensions(L, B, T) are fixed. In the second case both hull form and main dimensions are varied simultaneously. Finally, optimized hull form and its seakeeping performances are presented. The results of optimization procedure demonstrate that the optimized hull forms yield a reduction in vertical motion and acceleration. 相似文献
22.
R. S. Sharp S. A. Hassan 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1986,15(6):335-350
Passenger discomfort, suspension working space and dynamic tyre loading parameters are calculated for different combinations of spring stiffness and damping coefficient representing the suspension system in a quarter car model subject to realistic random disturbance inputs from roads of widely differing quality. Sprung and unsprung masses and the tyre vertical stiffness and damping coefficient employed derive from a current production car. Designs which are best for the specific conditions represented are identified and their performance properties in other (off-design) conditions are considered, and conventional design is explained as the inevitable consequence of the need to compromise if fixed suspension parameters are used. Performance improvements possible if variable parameters can be employed are evaluated as a function of the ranges of variability provided, and a stratagem for controlling parameters is proposed. 相似文献
23.
The aim of this study is to calculate hydrodynamic performance and ventilation flow around wedge, 2D blade and 3D surface piercing propeller (SPP), using computational fluid dynamic based on Reynolds-averaged Navier–Stokes method. First, numerical analyses for two-phase fluid flow around the wedge and 2D blade section (cupped and non-cupped) are presented. Flow ventilation, pressure distribution and forces are determined and compared with experimental data. Then, the method is extended to predict the hydrodynamic performance of propeller SPP-841B. The propeller exhibits a cupped blade. In the simulated configuration, SPP is one-third submerged (I = h/D = 0.33) and is working at various loadings with full ventilation occurring at low advance coefficient (J). The open water performance, pressure distribution, forces/moments and ventilation pattern on the SPP-841B model are obtained and compared with experimental data. The numerical results are in good agreement with experimental measurements, especially at high advance coefficient. 相似文献
24.
Ahmad Sanusi Hassan 《Transportation》2009,36(3):309-324
George Town, Penang, is the oldest British colonial city in South East Asia. The colonial settlement layout in the inner city
area is still intact today. The establishment of George Town as a trading centre had attracted immigrants from all over the
world, especially from Asia (Chinese, Indians and Arabs). Recently, George Town has been enlisted under the UNESCO World Heritage
Lists as an outstanding example of traditional multi-cultural settlement. The uniqueness of this inner city is that the formation
of its urban pattern is the result of ‘divide and rule’ concept adopted by the British authority. Under the ‘divide and rule’
concept, these immigrants were located to settlement areas based on their ethnic background under one leader known as ‘kapitan’ (captain). The study finds that transport access in this inner city was influenced by the ‘divide and rule’ concept. Unlike
formation of well-planned gridiron pattern in other British colonial cities such as in North America, Canada and Australia,
the formation of the urban pattern in George Town has an irregular gridiron pattern. This type of urban pattern is typical
under ‘divide and rule’ concept and this had indirectly influenced the setting and planning of the present street access and
transport networks.
相似文献
Ahmad Sanusi HassanEmail: |
25.
Osman Turan Chirstos Verveniotis Hassan Khalid 《Journal of Marine Science and Technology》2009,14(4):409-416
This article presents a new approach for the prediction of motion sickness on ships, with a focus on high-speed craft. The
methodology presented is based on a variant of the sensory conflict hypothesis and the human vestibular system. The proposed
model was developed using control theory and is capable of taking account of all six degrees of freedom vessel motion for
the prediction of motion sickness. Furthermore, full-scale trials were carried out onboard three different high-speed craft
to measure the ship motions and consequently to analyse their effects on passengers in terms of motion sickness. Through the
accumulated results, the developed model was validated and was compared with existing methods/criteria for the prediction
of the incidence of motion sickness. 相似文献
26.
Caisson breakwaters are mainly constructed in deep waters to protect an area against waves. These breakwaters are con-ventionally designed based on the concept ... 相似文献
27.
Ziaul Haque Munim Mariia Dushenko Veronica Jaramillo Jimenez Mohammad Hassan Shakil Marius Imset 《Maritime Policy and Management》2020,47(5):577-597
ABSTRACT This study provides a bibliometric review of 279 studies on the applications of big data and artificial intelligence (AI) in the maritime industry, published in 214 academic outlets, authored by 842 scholars. We extracted bibliographical data from the Web of Science database and analysed it using the Bibliometrix tool in R software. Based on citation analysis metrics, we revealed the most influential articles, journals, authors and institutions. Using the bibliographic coupling methodology, we identified four underlying research clusters: (1) digital transformation in maritime industry, (2) applications of big data from AIS, (3) energy efficiency and (4) predictive analytics. We analysed these clusters in detail and extracted future research questions. Besides, we present research collaboration networks on the institution and author level. 相似文献
28.
Hassan GHASSEMI 《船舶与海洋工程学报》2009,8(4):267-274
Demand for high-speed marine vehicles (HSMVs) is high among both commercial and naval users. It is the duty of the marine
vessel’s designer to provide a hull and propulsion system that diminishes drag, improves propulsive efficiency, increases
safety and improves maneuverability. From the propulsor side, surface piercing propellers (SPPs) should improve performance.
Unlike immersed propellers, behavior of the SPP is affected by depth of immersion, Weber number and shaft inclination angle.
This paper uses a practical numerical method to predict the hydrodynamic characteristics of an SPP. The critical advance velocity
ratio is derived using the Weber number and pitch ratio in the transition mode, then the potential based boundary element
method (BEM) is used on the engaged surfaces. Two models of three and six-bladed SPPs (SPP-1 and SPP-2) were selected and
some results are shown. 相似文献
29.
The development of microchannels with open flow for use in irrigation and rainy areas is challenged by electricity generation via hydrokinetic devices in shallo... 相似文献
30.
This paper presents a simulator model of a marine diesel engine based on physical, semi-physical, mathematical and thermodynamic equations, which allows fast predictive simulations. The whole engine sy... 相似文献