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1.
Jakobsson et al. (2000) found that in Sweden public acceptance of road pricing decreases if it is perceived to be unfair and to infringe on freedom. The present study reports a survey investigating whether the same effects are found in the Asian countries of Japan and Taiwan. The results indicate that fairness plays the same role. However, income had a direct effect on acceptance in Taiwan but not in Japan or Sweden.  相似文献   
2.
Jakobsson  Cecilia  Fujii  Satoshi  Gärling  Tommy 《Transportation》2002,29(4):349-370
A field experiment was conducted to investigate the effects of economic disincentives on private car use. Eighty two-adult households who were owners of at least one car were randomly assigned to three experimental groups and one control group. Both experimental and control groups logged their car trips during one week before, one week during, and one week after treatment. The treatment consisted of charging two of the experimental groups approximately 100% of normal cost per kilometer of driving during 2 weeks, and charging the third experimental group this amount per kilometer of driving during 4 weeks. With the purpose of investigating whether deliberate planning increases the effect of economic disincentives, the households in one of the former and in the latter group were asked to fill out a prospective car log for the following week. The control group was not charged or requested to fill out a prospective car log but was in other respects treated in the same way. Analyses of the car logs and odometer readings during and at the end of treatment showed a weak reduction of car use due to the economic disincentives that however were almost completely dependent on planning.  相似文献   
3.
The trend towards deepwater development requires a new approach to underwater installation of offshore structures. The present method using crane vessels has some drawbacks in operations at more than 2000 m depth. The natural period of the coupled system of the rigged structure and the crane vessel becomes longer, so that it is no longer possible to manipulate the cranes to achieve the desired positioning accuracy. This paper examines the application of an active control technique for underwater installations as one of the solutions to the present problems. An active control technique also has the advantage that it can deal with the structural flexibility which allows the structure to be large and light-weight. This structural flexibility imposes problems of suppressing the elastic responses and securing the stability of the control system. In this paper, anH controller combined with a low authority control/high authority control (LAC/HAC) feedback controller is designed for cases where structural flexibility cannot be ignored. A robust model-following controller is examined for cases where the structure can be treated as rigid. In order to confirm the control algorithm and verify the possibility of the active control installation method, basin tests are executed using two types of neutrally buoyant flexible models with ultrasound ranging systems and thrusters.  相似文献   
4.
The finite element model previously formulated to represent a bias-ply motorcycle tire is improved for more accurate orthotropic stiffness values. Efforts are centered on accurate mapping of the cord angle from an actual tire to the finite element model. Using this improved finite element model, the deformations of the bias-ply motorcycle tire subject to inflation pressure are analyzed.  相似文献   
5.
Previous research has shown that fairness, infringement on freedom, and perceived effectiveness are determinants of transport pricing acceptability. In the present study we investigate determinants of acceptability of environmental (carbon) taxation for which trust in government and environmental concern are additional determinants. Carbon taxation is an extension of fuel taxes and may thus be viewed as transport pricing. Our main focus is on the role played by personality traits. Structural equation modeling reveals that acceptability is related to the personality traits extraversion, agreeableness, and conscientiousness. Extraverted individuals have higher levels of trust in government which leads to higher acceptability. Also correlations between agreeableness and conscientiousness as well as environmental problem awareness and personal norm are observed. We discuss strategies for effective marketing of transportation policies considering how acceptability is related to personality traits.  相似文献   
6.
A finite element model suitable for camber thrust analysis is formed. By inclining and pressing this finite element model onto the road plane, the forces prevailing in the contact patch of an inclined standing tire are calculated and the asymmetry-dependent mechanism of camber thrust generation is analyzed. By rotating the inclined standing tire at a constant vertical deflection, the roll-distance-dependent mechanism of camber thrust generation is analyzed.  相似文献   
7.
For the theoretical consideration of a system for reducing skin friction, a mathematical model was derived to represent, in a two-phase field, the effect on skin friction of the injection of micro air bubbles into the turbulent boundary layer of a liquid stream. Based on the Lagrangian method, the equation of motion governing a single bubble was derived. The random motion of bubbles in a field initially devoid of bubbles was then traced in three dimensions to estimate void fraction distributions across sections of the flow channel, and to determine local bubble behavior. The liquid phase was modeled on the principle of mixing length. Assuming that the force exerted on the liquid phase was equal to the fluid drag generated by bubble slip, an equation was derived to express the reduction in turbulent shear stress. Corroborating experimental data were obtained from tests using a cavitation tunnel equipped with a slit in the ceiling from which bubbly water was injected. The measurement data provided qualitative substantiation of the trend shown by the calculated results with regard to the skin friction ratio between cases with and without bubble injection as function of the distance downstream from the point of bubble injection.List of symbols B law of wall constant - C f local coefficient of skin friction - C f0 local coefficient of skin friction in the absence of bubbles - d b bubble diameter [m] - g acceleration of gravity [m/s2] - k 1 k4 proportional coefficient - k L turbulent energy of the liquid phase [m2/s2] - L representative length [m] - l b mean free path of a bubble [m] - m A added mass of a single bubble [kg] - m b mass of a single bubble [kg] - N x ,N y ,N z force perpendicular to the wall or ceiling exerted on a bubble adhering to that wall or ceiling [N] - P absolute pressure [Pa] - Q G rate of air supply [/min] - q L (i) turbulent velocity at the ith time increment [m/s] - R> ex Reynolds number defined by Eq. 32 - T *L integral time scale of the liquid phase [s] - U velocity of the main stream [m/s] - ,¯v,¯w time-averaged velocity components [m/s] - u,v,w turbulent velocity components [m/s] - û L ,vL root mean square values of liquid phase turbulence components in thex- and y-directions [m/s] - V volume of a single bubble [m3] - X,Y,Z components of bubble displacement [m] - x s ,y s ,z s coordinate of a random point on a sphere of unit diameter centered at the coordinate origin - root mean square of bubble displacement in they-direction in reference to the turbulent liquid phase velocity [m] - local void fraction - m mean void fraction in a turbulent region - regular random number - R v increment of the horizontal component of the force acting on a single bubble, defined by Eq. 22 [N] - t time increment [s] - 1 reduction of turbulent stress [N/m2] - L rate of liquid energy dissipation [m2/s3] - m coefficient defined by Eq. 30 - law of wall constant in the turbulent region in absence of bubbles - 1 law of wall constant in the turbulent region in presence of bubbles  相似文献   
8.
This study focuses on the user-interface of the route guidance system with an electronic map display. The ultimate goal of the study is to aid in designing electronic map displays that can deliver information to the user most efficiently and expeditiously with minimum confusion. To evaluate the efficiency and understandability of a map display, laboratory experiments were designed and conducted in this study. In the experiments the subjects were presented with electronic map displays of different attributes and performed a set of tasks. Their understanding of the information contents was measured based on the outcomes of the tasks, and subjective ratings of the ease of using the maps were obtained. Using the experimental data obtained, a structural equations model system is developed to explain the understandability of a map display in terms of the subject’s attributes and the characteristics of the map display. The experimental procedure and the modeling results are presented in this paper.  相似文献   
9.
10.
MVNakhodka collapsed and broke in two on January 2, 1997 in the Sea of Japan, giving rise to a serious and disastrous oil spill on the coastline of Japan. During the inquiry into the cause of the accident, one of the main tasks of the inquiry committee was to identify the external loads which made the ship structure collapse. Among the several possible scenarios for the accident, after careful examination, the wave loads in the heavy weather at the time of the accident were taken to be the most plausible cause. The results of that research are described in two papers, and the present paper deals with the way in which wave loads on theNakhodka at the moment of the accident were estimated. We first describe the details of the accident such as the location, the sea condition, the loading condition, and the ship's heading speed. Then the static loads resulting from the distribution of the cargo weight and the buoyancy are given to show that the static bending moment at the time of the accident caused extreme sagging. Next the wave loads in the irregular waves, calculated by the nonlinear time domain simulation program SRSLAM, are presented. It is shown that the bending moment in the waves reaches 1 087 800 KN*m at maximum SS 6.9, which is where the hull girder collapse took place. It was concluded that the ship broke in two because the bending moment exceeded the hull girder strength which had been reduced due to corrosion, taking into account conclusions derived from the research dealing with the structural strength aspect. We also discuss the stochastic significance of the estimated value and nonlinear nature of the peak distribution, in addition to the effects of the ship speed and wave heading on the wave load estimation. This article is based on an article that appeared in Japanese in the Journal of the Society of Naval Architects of Japan, vol. 183 (1998).  相似文献   
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