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31.
In this article, I utilize the perspectives of economic sociology to examine the structural background of forest devastation in Japan. First, I explore the factors behind cited problems for the forestry industry and demonstrate that expanded imports of inexpensively priced foreign-sourced logs do not sufficiently explain those issues. On that basis, I then demonstrate that the concepts and analytical tools offered by economic sociology are essential to a full understanding of relevant problems. Next, to understand how the current crisis differs from that experienced by forestry households in the 1980s, I turn my focus to changes in the social networks that supported the trade in wood products. The crisis witnessed a transformation that involved disembedding sawmills from the traditional wood trading networks that had relied on cooperative ties with forestry households. Eventually, social relationships between forestry households and sawmills were severed and these households became unable to address their economic difficulties through their existing practices. Given that context, I then examine the contrasting economic behavior of sawmills and forestry households and demonstrate that exposure to global price competition forced forestry households into uncontrolled over-cutting. Finally, I assert that economic sociology is better able to provide a more precise understanding of the true nature of the problems facing forestry in modern-day Japan than conventional economics with its adherence to the useful but insufficient principles of market competition and economic efficiency.  相似文献   
32.
This paper evaluates the applicability of different multi-objective optimization methods for environmentally conscious supply chain design. We analyze a case study with three objectives: costs, CO2 and fine dust (also known as PM – Particulate Matters) emissions. We approximate the Pareto front using the weighted sum and epsilon constraint scalarization methods with pre-defined or adaptively selected parameters, two popular evolutionary algorithms, SPEA2 and NSGA-II, with different selection strategies, and their interactive counterparts that incorporate Decision Maker׳s (DM׳s) indirect preferences into the search process. Within this case study, the CO2 emissions could be lowered significantly by accepting a marginal increase of costs over their global minimum. NSGA-II and SPEA2 enabled faster estimation of the Pareto front, but produced significantly worse solutions than the exact optimization methods. The interactive methods outperformed their a posteriori counterparts, and could discover solutions corresponding better to the DM preferences. In addition, by adjusting appropriately the elicitation interval and starting generation of the elicitation, the number of pairwise comparisons needed by the interactive evolutionary methods to construct a satisfactory solution could be decreased.  相似文献   
33.
This paper investigates an integrated production and transportation scheduling problem in an MTO supply chain. A harmony search-based memetic optimization model is developed to handle this problem, in which certain heuristic procedures are proposed to convert the investigated problem into an order assignment problem. A novel improvisation process is also proposed to improve the optimum-seeking performance. The effectiveness of the proposed model is validated by numerical experiments. The experimental results show that (1) the proposed model can solve the investigated problem effectively and that (2) the proposed memetic optimization process exhibits better optimum-seeking performance than genetic algorithm-based and traditional memetic optimization processes.  相似文献   
34.
围绕中国碳中和目标的实现路径与模式选择问题,提出了一个中国应对气候变化整体治理模式,即多阶段混合主导型碳中和实现模式。这一模式是以国家为核心,在一定时期和内外环境约束下,通过减排和增汇路径,对中国境内由人类活动造成的CO2排放与人为CO2吸收量之间关系进行调整和平衡的过程;其内部由宏观、中观和微观三层结构组成,每层结构各不相同。多阶段混合主导型碳中和实现模式的提出,拓展和完善了气候变化整体治理理论,为气候变化治理提供了机制借鉴。  相似文献   
35.
In this paper, we introduce a new test for the dilation order based on cumulative residual Tsallis entropy of order α. The effect of the values of parameter α on the power of the test statistics is numerically investigated. The asymptotic distribution of the test statistic is given. The performance of the test statistic is evaluated using a simulation study. Finally, some numerical examples illustrating the theory are also given.  相似文献   
36.
This study focuses on the estimation of population mean of a sensitive variable in stratified random sampling based on randomized response technique (RRT) when the observations are contaminated by measurement errors (ME). A generalized estimator of population mean is proposed by using additively scrambled responses for the sensitive variable. The expressions for the bias and mean square error (MSE) of the proposed estimator are derived. The performance of the proposed estimator is evaluated both theoretically and empirically. Results are also applied to a real data set.  相似文献   
37.
When data are outcome-dependent non response, pseudo-likelihood yields consistent regression coefficients without specifying the missing data mechanism. However, it is onerous to derive parameter estimators including their standard errors from the regression coefficients under pseudo-likelihood (PL). The present study applies an imputation method to compute the asymptotic standard errors of parameter estimators. The proposed method is simpler than Delta method and it showed similar effect size of the standard errors to bootstrapping in simulation and application studies.  相似文献   
38.
In this article, we study the algorithm of Kiefer–Wolfowitz underquasi-associated random errors. We establish the complete convergence and obtain an exponential bound. Additionally, we build a confidence interval for the minimum. Numerical examples are sketched out to confirm the theoretical results and show the accuracy of the algorithm.  相似文献   
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