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排序方式: 共有2409条查询结果,搜索用时 765 毫秒
891.
This paper explores the effect of informed trading, heterogeneity investment and liquidity shocks on the valuation of credit default swaps (CDSs). Under the condition of asymmetric information, the informed trading plays an important role in the valuation of CDS. Instruction order flow has a significant influence on CDS price. And the scope of influence changes in accordance with different time interval, company status and the size of bid-ask spread. Heterogeneity of investors seriously affects the market liquidity and subsequently affects the CDS price. The bigger heterogeneity of the investment philosophy, investment habits, investment preference and so on is the bigger risk for market liquidity, and the higher price for CDS shall be. On the contrary, the conclusion is also consistent. The effectiveness of liquidity, whether it is before or after the financial crisis, dominates the fluctuation of CDS price. The premium of liquidity accounts for 36% to 50% of the CDS price.  相似文献   
892.
Floating wind turbines (FWTs) are subjected to combined aerodynamic and hydrodynamic loads varying both in time and amplitude. In this study, a multi-column tension-leg-type FWT (i.e., WindStar TLP system) is investigated for its global performance under normal operating conditions and when parked. The selected variables are analysed using a fully coupled aero-hydro-servo-elastic time domain simulation tool FAST. Three different loading scenarios (wind only, wave only and both combined) are examined to identify the dominant load influencing each response. The key response variables are obtained and compared with those for an NREL 5MW baseline wind turbine installed on land. The results should aid the detailed design of the WindStar TLP system.  相似文献   
893.
Concession period is a key factor in the arrangement of a build-operate-transfer (BOT) contract. This paper proposes a stochastic concession period model for infrastructure projects under a BOT scheme, which takes into account the impact of risks and the risk attitudes of the private investor and the government. A hypothetical case is simulated by using the Monte Carlo simulation method to illustrate the proposed model. The results indicate that even for a project with the same estimations, the concession interval can be different and depends a lot on the risk attitudes of the private investor and the government. The proposed model provides a more reasonable concession interval based on which a specific concession period can be obtained through negotiation between the two parties.  相似文献   
894.
With the rapid development of e-commerce, urban end distribution plays more and more important role in e-commerce logistics. The collection and delivery points (CDPs), between online retailers and customers, provide a way to improve the service quality of urban end distribution. But it will be more difficult to obtain an optimal solution of urban end delivery plan when many CDPs joint a complicated delivery network, since the solution space is always too large for many traditional heuristic algorithms to search. In this paper, a two-stage optimization method based on geographic information system (GIS) and improved cooperative particle swarm optimization (CPSO) is proposed. This method takes full advantage of powerful network analysis of GIS and strong global search of CPSO. A new cooperative learning mechanism, global sub-swarm, local sub-swarm and normal sub-swarm (GS-LS-NS), is used to improve the search mode of CPSO. Finally, several experiments are conducted to show the better performance of GIS-CPSO, compared with single PSO, GIS-CPSO and ArcGIS (software of GIS) separately. The conclusion of this research is much useful and applicable for logistics service providers.  相似文献   
895.
In this paper, a family of rate-compatible (RC) low-density parity-check (LDPC) convolutional codes can be obtained from RC-LDPC block codes by graph extension method. The resulted RC-LDPC convolutional codes, which are derived by permuting the matrices of the corresponding RC-LDPC block codes, are systematic and have maximum encoding memory. Simulation results show that the proposed RC-LDPC convolutional codes with belief propagation (BP) decoding collectively offer a steady improvement on performance compared with the block counterparts over the binary-input additive white Gaussian noise channels (BI-AWGNCs).  相似文献   
896.
This paper presents a dynamic model of pollution treatment strategies, driven by the bargaining relationships between governments, oil and gas companies and local residents. The results show that government plays a dominating role and government environmental policies have significant impact on other two parties’ behavior. To achieve better pollution treatment in the future, we put forward the following suggestions. An improvement in the legal system is required, and the legal enforcement needs to be strengthened. In terms of pollution treatment, responsibilities and obligations of these three parties need to be clearly defined. A wellfunctioned reward and penalties system needs to be established for minimizing the environment damage in the future.  相似文献   
897.
本文在分析移频信号的频谱特点的基础上,通过MATLAB仿真发现,用ZOOM-FFT方法提高频率分辨率是有前提条件的,该方法需要较长的采样时间,而这不能满足测试仪表实时性要求.并指出了ZOOM-FFT在检测轨道电路移频信号参数研究中的误区.  相似文献   
898.
刘芬  胡安  刘德志 《船电技术》2005,25(1):35-38
本文从带有高感性直流负载的三相全控整流电路稳态工作的物理情况出发,首先考虑了交流侧电感的影响,进而考虑交流侧电阻对直流电压、换相角的影响,将直流电压的平均值用麦克劳林级数表示,取前两项作近似,得出了实用的解析计算公式,并给出了计算步骤,实验证明该结果具有较高的精度.  相似文献   
899.
结合广东省河源市市内东埔河的综合整治,综述河道综合治理原则和措施以及治理中存在的问题,使城市与河道和谐相处,促进城市的可持续发展。  相似文献   
900.
城市绿地的喷灌设计简介   总被引:1,自引:0,他引:1  
简述城市绿地的喷灌技术及其设计计算,包括喷灌系统的组成及其造型、灌水量及管道的水力计算、管径和水泵的确定和选择等。设计合理的喷灌系统在满足需水要求的同时,可以满足景观和环境效果。  相似文献   
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