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991.
Maik Plenz Stephan Mattner Prof. Dr. rer. pol. Heinrich Degenhart Lars Holstenkamp 《能源经济杂志》2013,37(4):261-276
The present analysis provides a contribution to the question of how a system integration of large-scale energy storages can be implemented. It is to be investigated if and how federal waterways can be used for this purpose. Initially, a baseline study was carried out in which the federal waterways are systematically assessed with regard to their suitability for/as energy storage systems. Apart from the technical and the hydro mechanical implementation of the storage process, the advantages and disadvantages of the federal waterways in comparison to conventional pump storage stations play a significant role. A presentation and classification of the potentially available canal sections provides an overview of the suitable storage systems of the federal waterways. A specifically designed storage simulation on the basis of a sample application is used, in order to determine the capacity of the canal system for energy storage. Consequently, the simulation showed the theoretical capability of the federal waterways as energy storage systems, through their ability to balance the load and temporal fluctuations of the energy input. The simulation program Matlab was used on the basis of the synthetic load and delivery profiles. Finally, based on the example of the ships lock in Uelzen and the Scharnebeck boats lift, a simulation of the possible re-equipping options will be described, technically abstracted, economically analysed and combined with renewable energy facilities within a virtual power plant. The detailed formulation of further approaches and the calculation of possible application scenarios play a central role within this analysis. 相似文献
992.
Stephen H Schneider B. L. Turner Holly Morehouse Garriga 《Journal of Risk Research》2013,16(2):165-185
Decisionmakers at all scales (individuals, firms, and local, national, and international governmental organizations) are concerned about reducing their vulnerability to (or the likelihood of) unexpected events, 'surprises.' After briefly and selectively reviewing the literature on uncertainty and surprise, we adopt a definition of 'surprise' that does not include the strict requirement that it apply to a wholly unexpected outcome, but rather recognizes that many events are often anticipated by some, even if not most observers. Thus, we define 'imaginable surprise' as events or processes that depart from the expectations of some definable community. Therefore, what gets labelled as 'surprise' depends on the extent to which what happens departs from community expectations and on the salience of the problem. We offer a typology of surprise that distinguishes imaginable surprises from risk and uncertainty, and develops several kinds of impediments to overcoming ignorances. These range from the need for more 'normal science' to phenomenological impediments (e.g., inherentunpredictability in some chaotic systems) to epistemological ignorance (e.g., ideological blocks to reducing ignorance). Based on the input of some two dozen scholars at an Aspen Global Change Institute Summer Workshop in 1994 *, we construct two tables in which participants offer many possible 'imaginable surprises' in the global change context, as well as their potential salience for creating unexpectedly high or low carbon dioxide emissions. Improving the anticipation of surprises is an interdisciplinary enterprise that should offer a sceptical welcoming of outlier ideas and methods. 相似文献
993.
Buying and selling stocks causes price changes, which are described by the price impact function. To explain the shape of this function, we study the Island ECN orderbook. In addition to transaction data, the orderbook contains information about potential supply and demand for a stock. The virtual price impact calculated from this information is four times stronger than the actual one and explains it only partially. However, we find a strong anticorrelation between price changes and order flow, which strongly reduces the virtual price impact and provides for an explanation of the empirical price impact function. 相似文献
994.
The distributions of stock returns and capital asset pricing model (CAPM) regression residuals are typically characterized by skewness and kurtosis. We apply four flexible probability density functions (pdfs) to model possible skewness and kurtosis in estimating the parameters of the CAPM and compare the corresponding estimates with ordinary least squares (OLS) and other symmetric distribution estimates. Estimation using the flexible pdfs provides more efficient results than OLS when the errors are non-normal and similar results when the errors are normal. Large estimation differences correspond to clear departures from normality. Our results show that OLS is not the best estimator of betas using this type of data. Our results suggest that the use of OLS CAPM betas may lead to erroneous estimates of the cost of capital for public utility stocks. 相似文献
995.
B.R. Orton L. Sjöberg J. Jung D. ürge-Vorsatz M. Tamássyné-Bíró 《Journal of Risk Research》2013,16(1):17-29
Perceptions of risks from two groups of industrial radiographers, one from Hungary, (n = 45) and from the United Kingdom, (n = 29) were compared by the psychometric method. The comparison was made because both groups were at risk for high doses of ionizing radiation. We found the groups had similar demographic profiles but poor socio-economic conditions of Hungarians were associated with higher levels of emotional distress. Correlation HU-UK for personal and general risks were at a significant level for topics that included lifestyle and radiation risks. Perceptions of risks from radiation were small except for large personal risk from East European nuclear power plants. Knowledge of radiation risk intranationally was correlated positively with personal risk for UK radiographers and negatively for Hungarians. However, average overall risk perceptions from the same topic list for all radiographers did not differ significantly from a group (n = 1461) of UK citizens, though radiographer's risks from radiation were considerably greater. As a new lifesaving intervention it was proposed that radiation risk reduction could be achieved by genetic testing. 相似文献
996.
Michael L. Dekay Mitchell J. Small Paul S. Fischbeck R. Scott Farrow Alison Cullen Joseph B. Kadane 《Journal of Risk Research》2013,16(4):391-417
A decision-analytic model for avoiding a risky activity is presented. The model considers the benefit and cost of avoiding the activity, the probability that the activity is unsafe, and scientific tests or studies that could be conducted to revise the probability that the activity is unsafe. For a single decision maker, thresholds are identified for his or her current subjective probability that the activity is unsafe. These thresholds indicate whether the preferred course of action is avoiding the activity without further study, engaging in the activity without further study, or conducting a test or research programme to obtain additional information and following the result. When these thresholds are low, precautionary action is more likely to be warranted. When there are multiple stakeholders, differences in their perceptions of the benefit and cost of avoidance and differences in their perceptions of the accuracy of the additional information provided by the test or research programme combine to create differences in their decision thresholds. Thus, the model allows for the rational expression of differences among parties in a way that highlights disagreements and possible paths to conflict resolution. The model is illustrated with an application to phytosanitary standards in international trade and examined in terms of recent empirical research on lay perceptions of risks, benefits, and trust. Further research is suggested to improve the elicitation of model components, as a way of fostering the legitimate application of risk-based decision analysis in precautionary policy making. 相似文献
997.
B. Tóth Z. Eisler F. Lillo J. Kockelkoren J.-P. Bouchaud J.D. Farmer 《Quantitative Finance》2013,13(7):1015-1024
We present an empirical study of the intertwined behaviour of members in a financial market. Exploiting a database where the broker that initiates an order book event can be identified, we decompose the correlation and response functions into contributions coming from different market participants and study how their behaviour is interconnected. We find evidence for the following. (1) Brokers are very heterogeneous in liquidity provision—some appear to be primarily liquidity providers while others are primarily liquidity takers. (2) The behaviour of brokers is strongly conditioned on the actions of other brokers. In contrast, brokers are only weakly influenced by the impact of their own previous orders. (3) The total impact of market orders is the result of a subtle compensation between the same broker pushing the price in one direction and the liquidity provision of other brokers pushing it in the opposite direction. These results enforce the picture of market dynamics being the result of the competition between heterogeneous participants, interacting to form a complex market ecology. 相似文献
998.
Dr. Erik Hahn 《保险科学杂志》2013,102(5):519-536
The paper refers to legal questions that arise in connection with the collection and use of genetic data in the context of private insurance. The content and meaning of § 18 GenDG is described. Then, § 18 GenDG is set in relation to notification requirements out of the VVG. The paper exemplarily emphasizes that, despite the codification of GenDG, specific legal problems arise. Accordingly, the paper provides solutions to overcome these problems. Particular problems refer to the role of genetic data of third parties and according relations to the family history, possibilities to communicate genetic data by the insured in case of medical indication, the ratio of predictive and diagnostic genetic testing and the range of the total limits of § 18 I 2 GenDG. 相似文献
999.
The choice between fair value and historical cost accounting is the subject of long-standing controversy among accounting academics and regulators. Nevertheless, the market-based evidence on this subject is limited. We study the choice of fair value versus historical cost accounting for non-financial assets in a setting where market forces rather than regulators determine the outcome. In general, we find a very limited use of fair value accounting. However, the observed variation is consistent with market forces determining the choice. Fair value accounting is used when reliable fair value estimates are available at a lower cost and when they convey information about operating performance. For example, with very few exceptions, firms’ managers commit to historical cost accounting for plant and equipment. Our findings contribute to the policy debate by documenting the market solution to one of the central questions in the accounting literature. Our findings indicate that, despite its conceptual merits, fair value is unlikely to become the primary valuation method for illiquid non-financial assets on a voluntary basis. 相似文献
1000.