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61.
Abstract

The management and conservation of the marine environment and its natural resources are increasingly understood to be issues of public policy with consequences for society at large. On a variety of dramatic occasions over the last decades, the federal judiciary has departed from its traditionally passive role in the shaping of social policy. This paper examines a critical marine controversy, the Boldt Decision (U.S. v. Washington 1974), to illustrate and evaluate nontraditional judicial behavior. The first two sections introduce Indian‐United States treaties concerning Pacific Northwest salmon resources, and the unfolding of the Boldt Decision. A third section argues that a “public law”; model of litigation fits the legal events of the Boldt Decision. A fourth section addresses the competence of the Boldt court as it is manifest in judicial organization, analysis, and implementation. A final section comments on the potential for public law litigation elsewhere in the governing of marine affairs.  相似文献   
62.
介绍了美国加州洛杉矶港口停靠设施两种支挡结构的岩土工程勘探和设计成果,为了在码头提供两个驳船停靠点,要对现有堤坝边坡进行开挖,开挖后的边坡需要有支挡结构支撑。根据现场勘察和室内试验数据,项目地基为砂、泥质砂和黏土层,场地在运行地震水平下(震级5.5,峰值加速度0.28g)和偶发性地震水平下(震级6.5,峰值加速度0.52g)将会发生液化现象。建议支挡结构采用AZ型中心桩和AZ型辅助桩结合的钢板桩,并采用静力和运行震动水平共同作用下的侧压力分布图和极限平衡法分析确定桩长和截面尺寸。  相似文献   
63.
64.
Abstract

There is a growing phenomenon of grassroots innovation, that is, that triggered by individual users or communities (physical or virtual) seeking a solution to a personal or societal problem. This has great potential as a new source of sustainable transport innovations, but has received little attention to date. This study conducted 16 in-depth interviews and a workshop with grassroots innovators in transport. A detailed thematic analysis of the interview data identified: catalysts for the idea and the motivation behind its pursuit; the barriers experienced (those that were overcome and those that were not); and the enablers that permitted the innovations to continue and to flourish. The paper concludes by identifying the conditions that need to exist for such innovations to be created, developed and exploited in order that their potential for increasing the sustainability of the transport system can be fulfilled.  相似文献   
65.
Although containerization in Third World Asian ports may not conform to the ‘usual’ model of containerization in developed countries the region represents a significant generator of container tonnage. Moreover, despite considerable intra-regional differences in throughput productivities, some of the ports are achieving efficiencies and productivities markedly higher than those in well established ports in Western countries. The region has been characterized, too, by strong patterns of mainline/feeder interdependencies. This paper reviews the status of containerization in Third World Asia and suggests that major changes, reflecting a variety of factors, are likely by 1990.  相似文献   
66.
Based on a public survey of registered voters, we explore four options for internalising the social and environmental costs of road transport. The options were presented together with generalised factual information about their benefits and costs. Respondents are highly supportive of fuel use efficiency standards and exhaust gas quality standards, with lesser support for proposed initiatives of road user charges and speed reduction. Demographic analysis of responses enables identification of those who might favour or oppose particular options. In this case women are identified as being strongly supportive of the speed reduction option.  相似文献   
67.
The problem of estimating parameters and their uncertainty from experimental measurements in marine ecosystems is a common task and often necessitates solving nonlinear equations. If the measurements are subject to individually varying errors (i.e., heteroscedastic data), the parameters are often estimated using a Weighted Least Squares (WLS) method. For estimating the parameter uncertainties, a linearized expression for the covariance matrix exists. Yet, both methods assume that the errors on the independent variable, also called “input”, is negligible, which is often not true. For instance, in order to determine uptake and regeneration rates of silicic acid by phytoplankton, concentration and isotopic abundance measurements are performed at the beginning (input) and at the end (output) of an incubation experiment. Here, the so-called input and output are measurements of the same quantities, i.e., determined in exactly the same way, only differing by the time at which the measurements were performed. Clearly, there is no reason to assume that the input measurements are subject to less error than the output measurements. We propose a refinement of the two abovementioned estimation methods which enlarges their applicability to cases where input noise is not negligible. The refined methods are evaluated on the uptake and regeneration processes of silicic acid and compared to the original procedures using Monte-Carlo simulations. The results reveal a smaller bias for the refined WLS estimator compared with the original one. An additional advantage of using the refined WLS cost function is that its residual value can be interpreted as a sample from a χ2 distribution. This property is especially useful because it enables an internal quality control of the results. In addition, the parameter uncertainty estimation is significantly improved. By neglecting the effect of the input noise, a (potentially) important origin of the parameter variation is simply ignored. Therefore, without the refinement, the parameter uncertainties are systematically underestimated. Using the refined method, this systematic error disappears and on the whole, the parameter standard deviations are accurately estimated.  相似文献   
68.
Abstract

Natural resource management entities such as the Regional Fishery Management Councils established by the Magnuson Fishery Conservation and Management Act of 1976 depend heavily on science to inform policymakers and to legitimate the policy process. This paper discusses the importance of fishery science to the council system, contrasts the functions of Scientific and Statistical Committees (SSCs) serving the Pacific Fishery Management Council and the New England Fishery Management Council, and remarks on the implications of differences in the display of scientific authority by these SSCs.  相似文献   
69.
This paper explores the properties of inverse Box-Cox and Box-Tukey transformations applied to the exponential functions of logit and dogit mode choice models. It is suggested that inverse power transformations allow for the introduction of modeler ignorance in the models and solve the “thin equal tails” problem of the logit model; it is also shown that they allow for asymmetry of response functions in both logit and dogit models by introducing alternative-specific parameters which make cross elasticities of demand among alternatives generally asymmetric. In the dogit model, modeler ignorance and consumer captivity remain conceptually distinct. Standard logit and dogit models appear as very special “perfect knowledge” cases in broad spectra of models which also include, among others, the reciprocal extreme value or log-Weibull variants. These improvements over the simple symmetric-thin-equal-tail-perfect-knowledge logit and the symmetric-pure-captivity dogit are achieved at the cost of introducing at the most two new parameters per alternative considered in the original logit and dogit mode choice models.  相似文献   
70.
The dogit model     
This paper presents the dogit model. That model is flexible enough to permit the choice among specific pairs of alternatives to be consistent with the independence from irrelevant alternatives axiom, as in a logit model, but it simultaneously allows the choice among other pairs not to be. Dogit parameters add an “income effect” to the “substitution effect” already built into the logit model; alternatively, they allow for the joint presence of compulsive and discretionary elements in consumer behavior, or for the identification of captive markets. Eventual estimation of the values of the parameters of the dogit model appears simpler than for the probit model.  相似文献   
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