P2P网络中基于随时间推移的风险值评估的信任管理模型

针对现有的对等(P2P)网络信任管理模型中存在的问题:忽视短期交易时间与长期交易时间对信任值的不同影响以及缺少对交易对象资源的具体风险分析,在现有信任管理模型的基础之上,以不同用户对同一种类资源所提供的资源品质和风险作为关注点,引入风险值评估的概念,建立了基于随时间推移的风险值评估的信任管理模型。仿真结果表明,该模型使得恶意节点的行为得到有效控制,对交易资源的分析量化更加深入,进一步有效地帮助用户筛选出最优的交易者。

机场航站楼突发传染病疫情事件的多危害风险整合

为评价机场航站楼不同危害组的风险,将多危害风险整合法(MHRI)应用于机场航站楼突发传染病疫情事件多危害组的风险整合评估。首先,构建机场航站楼传染病疫情事件多危害风险因素结构层次框架,列出多危害组的风险指标;然后采用模糊层次分析法(FAHP)计算各指标的权重,运用关联系数法计算单个危害组的风险评价值,再采用改进的风险整合模型将不同危害组的风险进行整合,计算多危害组的总风险评价值。最后应用MHRI法对机场航站楼内部风险和突发传染病疫情事件外部风险进行整合评估,结果表明,MHRI法在机场航站楼多危害风险整合研究中具有一定的适用价值,可为机场航站楼发生新冠疫情等突发传染病事件时的风险管理提供参考。

基于智能WBR-LIEA算法的电网输电线路中山火预警监测研究

为了维护电网安全稳定运行,加强对山火的预防,通过考虑主备路由的链路重要度评估算法(Link Importance Evaluation Algorithm Based on Working and Backup Routing,WBR-LIEA)对电网输电线路中山火预警监测系统进行了优化。首先对山火预警监测系统进行了分析,然后利用WBR-LIEA算法对山火预警系统从服务层、传输层和物理拓扑层进行了关联风险值的评估,再将三个层面的链路关联风险进行融合,用来度量网络中链路的重要度。当链路失效引起路由中断时,控制器将按照重要度对路由进行重新分配,避免山火对报警通信系统产生影响,导致预警不及时。最后在电力通信网上对算法进行仿真实验并进行了相关分析,证明了该算法的准确性和有效性。

基于Muhlbauer法的天然气埋地管道评价

一条长输管道建成并投入使用后,由于输送介质、所处环境以及其他因素的影响,就会存在许多非常规危害的风险,影响到管道的使用寿命,甚至会在使用过程中出现各种事故。因此,为了控制管道风险,需要对管道进行风险评价,本文运用Muhlbauer风险评价法对天然气埋地管道进行评分,通过评分结果显示和各影响因子分析,可以通过加强管理的方法,采取相应措施,提高管道的安全性能。本文对Muhlbauer风险评价法在天然气埋地管线的评分应用进行了探讨。

Value evaluation of ecological risk of marine chemical spills

The environmental risk of chemical spills near coastal zones threatens abundant marine ecological resources. By appraising the ecological damage value of the environmental risk of marine chemical spills, we can facilitate decision-making for the development of a coastal zone and establishment of economic policy on coastal zone management. In this study, the ecological effect of the environmental risk of a chemical spill in the Haicang chemical industrial park in Xiamen was identified, after which its impact was forecasted and its ecological damage value was assessed. The information generated in this study will be useful in future studies evaluating marine ecological compensation based on environmental risk analysis.

Building Vulnerability Evaluation in Landslide Deformation Phase

Building vulnerability evaluation is important in the risk assessment on earthquake and flood hazards. But for landslide hazard, it is also a very important part for the people in buildings. Most discussions or researches about building vulnerability are for landslide failure, few for landslide in deformation phase. For this objective, this paper discussed about building vulnerability evaluation using Zhaoshuling landslide as an example Zhaoshuling landslide named located in the Three Gorges Reservoir Area, China. After a field survey on the geological condition of landslide, detailed field investigation on the buildings' location and structure is carried out. To get landslide surface deformation, numerical simulation method is used under the combining condition of water fluctuation and rainfall. Then building deformation and probable damage degree is analyzed according to landslide surface deformation and the relative theory in mining. Based on the national standard building damage classification system, the vulnerability of all the buildings on the landslide is semi-quantitatively evaluated.

Preliminary aquatic life criteria development and ecological risk assessment of ammonia in seven major river basins in China

Ammonia is one of the basin indices which are nation-controlled in the waterenvironmental management. In order to assess the differences of ammonia criteria indifferent basins, 7 major basins are used for the study object, including Songhua River,Liaohe River, Haihe River, Yellow River, Huaihe River, Yangtze River and ZhujiangRiver, referring the water environmental criteria technology of the United StatesEnvironmental Protection Agency, based on the effects of water characteristics on theecotoxicity of ammonia, and in summer and non-summer situation, aquatic life criteriais derived for ammonia. The results showed that: (a) The differences between thecriteria values in different basins and different seasons were significant. The differencesbetween the criteria values in different basins were greater than 6 times, while those indifferent seasons in the same basin were greater than 2 times. (b) The summer acuteand chronic criteria for Huaihe River were 0.37 mg/L and 0.06 mg/L while thenon-summer values were 0.81 mg/L and 0.15 mg/L. Both the summer and thenon-summer values were lowest in all of the seven basins. (c) The preliminaryassessment of Ammonia exposure ecological risk indicated that was the lowest inZhujiang River, and it was much lower in Songhua River, Liaohe River and YangtzeRiver, and was higher in Yellow River, and the highest in both Haihe River and HuaiheRiver. Haihe River has 7 sections while 2 in high risk, and Huaihe River has 27 sectionswhile sixteen in high risk. According to the differences of the criteria values for ammoniain seven basins in different seasons and difference of ammonia ecological riskassessment, it is suggested that it should be managed by different policies.

Numerical Simulation and Probabilistic Hazard Assessment of Tephra Fallout at Jinlongdingzi Volcano,Longgang Volcanic Field in Jilin Province

Tephra fallout is an important type of hazard caused by explosive volcanic eruption, and numerical simulation has become a fast and effective approach to assess the dispersion and deposition of tephra fallout. According to the improved 2D diffusion model of Suzuki （ 1983）, we edited a tephra diffusion program that can run in the Windows system. Based on previous data, we simulated the diffusion scope of the Jinlongdingzi volcanic eruption, which is the latest eruption in the Longgang volcanic cluster. The simulated results are in good agreement with the results from measurement in situ, indicating that the model is reliable and the parameters used in the model are suitable. By using wind profiles of ten years, 7, 021 simulations under different wind profiles were carried out, and then probabilistic hazard maps of tephra fallout were constructed for tephra thickness thresholds, lcm and 0.5cm. This study can provide an important scientific basis for volcanic hazard analysis, risk mitigation plans and countermeasures in the Longgang volcanic area.

某地块土壤中镍污染现状调查

工业企业搬迁遗留场地变更为居住、商业等用地,其土壤污染物类型、种类繁多,且因地而异。本文对某地块土壤中镍污染现状进行了初步调查检测,检测结果表明该地块土壤受到镍的污染较大,需进行风险评估和土壤修复后,才能用于居住或商业等建设用地。

The applied value of modified POSSUM score in evaluating lung cancer surgery’s risk

Objective: The aim of this study was to explore the modified physiological and operative severity score for the enumeration of mortality and morbidity (POSSUM) scoring system and the relationship between predicted data and actual data of complication and surgical mortality of lung cancer radical surgery made by such score system. Methods: Retrospective analysis on the 86 cases of the clinical materials of patients with primary lung cancer radical surgery for thoracic surgery of line lung cancer in the 81st Hospital of PLA from October 2010 to October 2011 and using the POSSUM scoring system to predict the cases of postoperative complication and death toll, then making a comparison with the actual cases. Results: The POSSUM scoring system predicting 29 cases of postoperative complications, but 32 cases of practical complications, the difference between them has no statistical significance (P﹥0.05), 8 cases of predicted postoperative deaths, 2 cases of practical deaths, by comparison, there was statistical significance (P﹤0.05). Conclusion: The modified POSSUM scoring system can be used to predict the postoperative complication of lung surgery patients, but sometimes overestimates the postoperative death cases.

A Correction for Classic Performance Measures

Non-normality in asset returns is now a common feature of financial markets. However, many practitioners as well as investors do still refer to classic risk adjusted performance measures to assess their investment. For example, Sharpe and Treynor ratios are designed for a Gaussian world. Then, employing them for a performance assessment prospect relative to the risk borne is a biased approach. If we look for consistency in risk assessment and in asset performance valuation, we need to look for robust methods or tools. Moreover, the well-known mathematical consistency and numerical tractability concerns drive our preference for simple methods. Under this setting, we propose to account in a simple way and to some extent for the skewness and kurtosis patterns describing the deviations from normality. We adjust therefore the classic Sharpe and Treynor ratios to asymmetries in the downside and upside deviations from the mean values of asset returns. Specifically, the adjusted Sharpe and Treynor ratios are weighted by the upside and downside deviation risks. Accounting for skewness and kurtosis changes generally the ranking of hedge fund performance. Moreover, the obtained adjusted performance measures capture well the skewness and/or kurtosis patterns in hedge fund returns depending on the targeted investment strategy

INTEREST RATE RISK PREMIUM AND EQUITY VALUATION

The authors employ the recent stochastic-control-based approach to financial mathematicsto solve a problem of determination of the risk premium for a stochastic interest rate model,andthe corresponding problem of equity valuation.The risk premium is determined explicitly,by meansof solving a corresponding partial differential equation (PDE),in two forms:one,time-dependent,corresponding to a finite time contract expiration,and the simpler version corresponding to perpetualcontracts.As stocks are perpetual contracts,when solving the problem of equity valuation,the latterform of the risk premium is used.By means of solving the general pricing PDE,an efficient equityvaluation method was developed that is a combination of some sophisticated explicit formulas,and anumerical procedure.

Development of a mathematical model to evaluate the rate of aggregate risk of invasive alien plant species： Fuzzy risk assessment approach

This study presents a novel approach to evaluate the rate of aggregate risk of Invasive Alien Plant Species. Using risk values and grade of importance of weights of risk factors which may reflect invasiveness of plant species are considered. We use Linguistic Ordered Weighted Averaging operator to evaluate the grade of important of weights. Since the risk values and important weights are identified from two different linguistic term sets, fuzzy set theory techniques were used to combine the two sets. The rates obtained from the model were compared with NRA risk levels and the model was validated with data from known and non-invasive species. The model is improved by weighting the risk values of risk factors. The improved model produced significant results and resulted a better tracking system for identifying potential invaders than the conventional risk assessment.