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11.
We estimate the welfare gain from innovations in the LCD TVs that prevailed during the period 2005–2007 in Japan, via consumer surplus that we measure with the aid of discrete choice methods, using market data obtained from an internet price comparison service (Kakaku.com). Further, by the measured implicit values of attributes, we evaluate in monetary terms, the qualitative transition embedded in the attributes through the iso-consumer surplus planes. We thereby disaggregate the welfare gain into the qualitative and the budgetary components, which we call the quality gain, and the budget gain, respectively. The estimates show, along with the evolved process of innovation, that the quality gain was in the order of 381 KJPY, while the budget gain was 94 KJPY negative, which gives about 287 KJPY of overall welfare gain per consumer, during the period.  相似文献   
12.
The present study explores public pension claiming behaviour among the Japanese elderly. First, we perform financial simulations, estimate expected utility and depict the typical patterns of pension benefits over a lifecycle. We show that a beneficiary's optimal retirement age depends on that beneficiary's mortality risk, discount rate, initial wealth and risk attitude. Second, we use individual‐level data from the Japanese Study on Aging and Retirement (JSTAR) to empirically examine the determinants of claim timing. We find evidence that most of the factors examined in the simulation are, indeed, significantly associated with early claiming among wage earners of pension benefits.  相似文献   
13.
Periodic flooding alters riverine vegetation community composition; moderate flood disturbance maintains communities at an early seral stage, whereas severe floods may remove entire communities. After disturbance, plants may recolonize riverbeds from refugia.Here, we investigated the morphological characteristics of refugia where riverine plants survived large floods. At three sites, plant communities growing on cobble-bars were surveyed, and the hydraulic characteristics of each site were analyzed. The populations of an indicator plant, Anaphalis margaritacea sub-species yedoensis (Franch. et Savat.) were assessed after major floods in 2004 and 2009. At each survey, the particle size and bed composition were measured, and the critical shear-stress required to move particles at each site was calculated. A one-dimensional flow and the average and local shear-stress at ten different discharges, including that of the largest flood were calculated. The results demonstrate that the A. margaritacea community is maintained at locations where the local shear-stress at peak discharge in large-floods does not exceed a critical value. These conditions were achieved in locations with particular morphological characteristics, where the river is not constrained by levees and is restricted by a downstream narrow-pass; in this reach river width increases with discharge thus limiting the increase in water depth with increasing discharge and allowing the establishment of refugia where plant species may survive large floods.Flooding and reestablishment from refugia maintain a characteristic riverbed community in equilibrium.  相似文献   
14.
Despite many previous investigations, there is no theoretically justifiable equation to determine the freshwater discharge, tidal velocity, and salinity in a complex estuary that contains several branches. In this study, the longitudinal distributions of freshwater and salinity concentration in multi-branched estuaries are investigated using a mathematical model, considering the energy balance by frictional head loss and the salt balance by diffusion and advection in a one-dimensional steady-state condition. We attempt to obtain the time-mean freshwater discharge rate quantitatively at a junction where the main flow separates into two branches. The salinity distribution along each branch is calculated by following the dispersion coefficient equation previously proposed for a single estuary. The salinity field is divided into the near-coast region and the upstream region, because in each segment the inland velocity varies according to the tidal flux. For computing the tidal velocity, we propose the Burgers equation and the Hoph-Cole transformation. The theoretical results obtained by these equations were found to be in good agreement with a set of observed data in the Red River estuary system.  相似文献   
15.
We evaluate the expected loss and the standard deviation of loss of a bank loan, considering the bank’s strategic control of the expected return on the loan. Assuming that the bank supplies an additional loan to minimize the expected loss of the total loan, we provide analytical formulations for the expected loss and the variance of loss with bivariate normal distribution functions. Using a given expected growth rate and interest rates, two thresholds for the asset/liability ratio can specify three cases. The bank supplies an additional loan to decrease the expected loss in two cases: (i) the asset/liability ratio of the firm is low, and its expected growth rate is high; and (ii) the asset/liability ratio of the firm is high, and the lending interest rate is high. The bank maintains the current loan amount when the asset/liability ratio lies between the two thresholds. Depending on the bank’s strategy, the bank can decrease the initial expected loss of the loan. Conversely, the bank would face a greater risk of the standard deviation of loss.  相似文献   
16.
This paper summarizes the results of personal exposure monitoring and estimates the risk from exposure to 18 volatile organic compounds compared with health criteria set by the US Environmental Protection Agency. In study 1, personal exposure levels and outdoor air concentrations were compared, and in study 2, personal exposure levels and the corresponding indoor air concentrations were compared. From these studies, it was concluded that personal exposure to volatile organic compounds depended markedly on indoor air quality and that handling of compounds increased personal exposure markedly. Risk estimations indicated that chloroform in tap water, benzene from cigarette smoke and p -dichlorobenzene from household insecticide needed caution.  相似文献   
17.
This paper evaluates a recently published semi-survey international input–output table for nine East-Asian countries and the USA with four non-survey estimation alternatives. A new generalized RAS procedure is used with stepwise increasing information from both import and export statistics as optimisation constraints on the four non-survey tables. The results show that the estimated table improves when increasing information from both sources is used, despite the well known inconsistencies between import and export data in trade statistics. It is concluded that the new procedure can be useful as a critical analysis of newly published (semi-)survey international tables and/or as an early updating tool during the construction process.  相似文献   
18.
Lack of access to high-quality education remains a serious concern in many developing countries. This is especially the case for rural areas, including islands suffering from a shortage of skilled teachers and sufficient educational equipment. We examine the impact of introducing TV-aided model lessons in class to enhance the quality of teaching (the EQUITV project) on the national examination test scores of Mathematics and “Combined Subject” (a comprehensive subject comprising 30% science and 70% social studies and other topics) as well as English in the final year of primary education in Papua New Guinea. We employ a panel event study to capture the different timings of the intervention across schools over multiple time periods. We find that the project significantly and robustly improved test scores for girls only in English 3 years after the introduction of the project, but no improvement was seen for boys.  相似文献   
19.
In this study we investigated the nature of disagreement, which is a necessary component of a good discussion. We obtained 27 group discussion scenes by Japanese undergraduates that were evaluated by two ways: impression rating and ranking. As a result of factor analysis for the impression rating data, five factors were extracted: activeness, multidirection and unification of discussion, relationships of participants, development and sophistication of discussion, and sincerity of the participants, and each factor scores of each scene was simultaneously calculated. Each scene’s rank score was also calculated by relative comparisons. A significant positive correlation was found between the mean factor and the rank scores except for Factor 3 (relationships of participants). To consider the reason for the difference relating to Factor 3’s score, we scrutinized the discussion process of four scenes of the different patterns of the factor and rank scores. From the analysis of conversations, we suggested that this difference reflected ways of disagreement. By introducing a probative discourse tags for discussion (pDTD), we reasoned that the frequency of disagreement made Factor 3’s score negative and the absence of the second part of adjacency pairs made the rank score worse. The explicit speech and actions of blame such as emotional and aggressive expression, and neglect of treatment for the minor opinion made also the discussion unfair, but we think that these behaviors might erupt from the ground made by the accumulated implicit behaviors such as the absence of the second part. We finally concluded that the criticism type of disagreement increased the rank scores, and its censure type produced lower results, and the proper ways of disagreement in group discussions were discussed.  相似文献   
20.
High concentrations of manganese and iron in the Saigon River are major problems for the water supply in Ho Chi Minh City (HCMC), Viet Nam. To identify their sources and leaching processes, we surveyed water quality along the Saigon River and ran batch leaching tests using soil and sediment samples. Two important leaching processes were identified: acidic leaching from acid sulfate soil (ASS) in the middle reaches of the river, and Mn dissolution and Fe reduction from sediments in the downstream reaches. Low pH caused the concurrent release of Fe and Mn from the ASS. In contrast, anoxia caused the release of Fe but not Mn from the sediments, whereas low pH facilitated Mn dissolution. Sediments are a more important source of Mn because of their higher Mn contents (10 times) and release rates (14 times) than those from ASS.  相似文献   
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