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101.
Onshore wind energy utilisation in Germany has developed very dynamically in the last decade. This has mainly been driven
by the renewable energy laws that systematically support the expansion of renewable energy in the electricity sector. In 2009
a revised law with increased feed-in tariffs for wind energy has come into force. Existing studies already predict a wide
range of development patterns under the Renewable Energy Sources Acts 2000 and 2004. This paper investigates the long term
impact of different feed-in tariffs implemented by the legislative authorities and it provides corresponding future development
patterns of onshore wind energy utilisation in Germany. The underlying System Dynamics model considers technical as well as
economic conditions and constraints. The approach and the model’s results are contrasted with other published predictions
qualitatively and quantitatively. This comparison shows that the model’s outcome lies in the range of predictions by existing
studies, but also shows some interesting differences.
Zusammenfassung Die Entwicklung der Windenergienutzung in Deutschland wahrend der letzten Dekade verlief sehr dynamisch. MagBgeblich dafur war die systematische Forde-rung mittels der Erneuerbare Energien Gesetze (EEG) bzw. deren Vorlaufer. Vom Jahr 2009 an gilt ein uberarbeitetes Gesetz, welches u.a. erhohte Einspeisever-gutungen furWindenergie beinhaltet.Vorliegende Studien, die sich mit derzu-kunftigen Entwicklung auseinandersetzten, zeigen bereits deutlich unterschied-liche Szenarien fur die Entwicklung unter dem EEG 2000 und 2004. Diese Arbeit setzt sich mit den langfristigen Auswirkungen der verschiedenen vom Gesetz-geber festgelegten Einspeisetarife auseinander und stellt entsprechend unter-schiedliche Ausbauszenarien fur die deutsche Onshore Windenergienutzung dar. Das zugrunde liegende System Dynamics Modell berucksichtigt dabei sowohl technische als auch okonomische Parameter. Der Ansatz sowie die Ergebnisse werden anderen veroffentlichten Prognosen gegenubergestellt. Die Ergebnisse liegen innerhalb der Spannbreite der anderen berucksichtigten Studien, zei-gen jedoch auch interessante Unterschiede.相似文献
102.
103.
The paper proposes in a regime-shift framework, an arbitrage-free term structure model based on the target and Fed Funds Rates. Empirical observations suggest that a three-state regime-shift environment associated with FOMC monetary actions is justified. Then, a closed-form solution for zero-coupon bonds is derived where regime-shift risk is priced. The solution is flexible enough to incorporate additional state variables. 相似文献
104.
Roberto Coda Dirceu da Silva Isaias Custodio 《International Journal of Human Resource Management》2013,24(14):1827-1847
This study describes the creation and validation of a multidimensional model which assesses the level of employee satisfaction based on international theoretical models. It utilizes data collected from a sample of 518 public and private company employees during the year 2009 in the city/state of São Paulo, Brazil. In the first stage of the study, 15 independent dimensions were theoretically obtained. In the second stage, five different multiple dimensions were confirmed using structure equation modeling (SEM) technique, thus characterizing general configurations of the organizational climate construct denominated motivation, management philosophy, leadership, people management and nature of work. It is hoped that the model can contribute by enhancing managerial best practices of an organization by attending a major demand for those listed on stock markets, since these companies must periodically provide information on job satisfaction of their employees to maintain or achieve higher levels of corporate governance. 相似文献
105.
Abstract The article examines the role of the board of directors in Local Public Utilities (LPUs). It aims at verifying empirically if a correlation exists between specific characteristics of the board of directors and the adoption of innovative arrangements addressing emerging needs of users and citizens (i.e. quality). By means of applying multivariate statistical methods to a random sample of sixty Italian LPUs, this study finds the relational capital of the boards affecting the take up of quality-oriented actions by LPUs. These results support the resource-dependence theory, neglected by mainstream literature. 相似文献
106.
Xiaodong Yan Hongni Wang Wei Wang Jinhan Xie Yanyan Ren Xinjun Wang 《International Journal of Forecasting》2021,37(3):1147-1155
This article considers ultrahigh-dimensional forecasting problems with survival response variables. We propose a two-step model averaging procedure for improving the forecasting accuracy of the true conditional mean of a survival response variable. The first step is to construct a class of candidate models, each with low-dimensional covariates. For this, a feature screening procedure is developed to separate the active and inactive predictors through a marginal Buckley–James index, and to group covariates with a similar index size together to form regression models with survival response variables. The proposed screening method can select active predictors under covariate-dependent censoring, and enjoys sure screening consistency under mild regularity conditions. The second step is to find the optimal model weights for averaging by adapting a delete-one cross-validation criterion, without the standard constraint that the weights sum to one. The theoretical results show that the delete-one cross-validation criterion achieves the lowest possible forecasting loss asymptotically. Numerical studies demonstrate the superior performance of the proposed variable screening and model averaging procedures over existing methods. 相似文献
107.
目前在确定煤层气井的渗透率及储层参数时,广泛采用注入/压降测试的方法,单项注入/压降测试是目前煤层气勘探开发中最常用、最有效的试井方法。本文全面阐述了煤层气井注入/压降试井的施工工艺、施工工艺中存在的问题。 相似文献
108.
以马牌轮胎上海物流中心为例,分析了重力式自动仓储系统的关键技术设备以及影响空间布局优化的因素,依据布局优化原理对轮胎的重力式自动仓储系统提出布局优化方案。 相似文献
109.
Roberto Colombi Subal C. Kumbhakar Gianmaria Martini Giorgio Vittadini 《Journal of Productivity Analysis》2014,42(2):123-136
This paper considers the estimation of Kumbhakar et al. (J Prod Anal. doi:10.1007/s11123-012-0303-1, 2012) (KLH) four random components stochastic frontier (SF) model using MLE techniques. We derive the log-likelihood function of the model using results from the closed-skew normal distribution. Our Monte Carlo analysis shows that MLE is more efficient and less biased than the multi-step KLH estimator. Moreover, we obtain closed-form expressions for the posterior expected values of the random effects, used to estimate short-run and long-run (in)efficiency as well as random-firm effects. The model is general enough to nest most of the currently used panel SF models; hence, its appropriateness can be tested. This is exemplified by analyzing empirical results from three different applications. 相似文献
110.
In contingent valuation studies, observed behavioral choices often enter as independent variables in the willingness to pay function. However, these variables may be endogenously determined when the error term in the behavioral model is correlated with the error term in the willingness to pay model. We investigate the effects of correcting for the endogeneity of a variable, namely membership status in environmental organizations that proxies unobservable characteristics of the respondents. Jointly modeling the membership variable and the willingness to pay response yields an estimate for the effect of the former that contradicts previous findings but is intuitive and agrees with theoretical expectations. 相似文献