This study aimed to screen drought stress indicators and analyze the drought resistance in 105 cultivated rice germplasm resources in Guangxi Zhuang Autonomous Region under drought stress in the whole growth period ba...This study aimed to screen drought stress indicators and analyze the drought resistance in 105 cultivated rice germplasm resources in Guangxi Zhuang Autonomous Region under drought stress in the whole growth period based on D value of seven morphological traits including panicle neck thickness,effective panicle number per plant,1 000-grain weight,filled grain number per panicle,total grain number,seed setting rate and yield per plant.According to the results,under drought stress,yield per plant exhibited significant positive correlation with panicle neck thickness and exhibited extremely significant positive correlation with other five morphological traits.Based on the identification and evaluation of comprehensive drought-resistance index D value,seven highly drought-resistant cultivated rice varieties were screened,accounting for 6.67%.Upland rice germplasm resources in Guangxi Zhuang Autonomous Region possess strong drought-resistance capacity,which could be used to screen highly drought-resistant rice germplasm materials.This study provided material basis and theoretical reference for breeding drought resistant rice cultivars in Guangxi Zhuang Autonomous Region.展开更多
Through field observation and lab analysis, 13 agronomic traits, including plant height and effective branching number per plant, etc., of 207 faba bean (Vicia faba L.) germplasms saved in Crop Middle-term Genebank ...Through field observation and lab analysis, 13 agronomic traits, including plant height and effective branching number per plant, etc., of 207 faba bean (Vicia faba L.) germplasms saved in Crop Middle-term Genebank of Hubei Province were evaluated, moreover, the identification on the disease resistance and the quality was carried out on parts of germplasm resources. The results showed that the faba beangermplasm resources in Hubei Province were abundant, the variation range of agronomic traits like the growth period, plant height and 100-bean weight, etc., was great, and the range of choice was wide. In the aspect of quality, there were 9 germplasms withthe content of crude protein higher than 30%, and the variation range of amylose content in total starch was large, which provided excellent sources of parents for breedinq hi.qh-quality faba bean varieties in Hubei Province.展开更多
This study focuses on revealing the relationship between uncertainty and investment probability through real option model involving investment critical trigger and project earning. Use of Matlab software on the experi...This study focuses on revealing the relationship between uncertainty and investment probability through real option model involving investment critical trigger and project earning. Use of Matlab software on the experimental results showing that project earning volatility influences investment probability, led the authors to conclude that this notion is not always correct, as increasing uncertainty should have an inhibiting effect on investment, and that in certain situation, increasing uncertainty actually increases the investment probability and so, should have positive impact on investment.展开更多
Most of modern systems for information retrieval, fusion and management have to deal with more and more qualitative information (by linguistic labels) besides information expressed quantitatively (by numbers), sin...Most of modern systems for information retrieval, fusion and management have to deal with more and more qualitative information (by linguistic labels) besides information expressed quantitatively (by numbers), since human reports are better and easier expressed in natural language than with numbers. In this paper, Herrera-Martfnez's 2-Tuple linguistic representation model is extended for reasoning with uncertain and qualitative information in Dezert-Smarandache Theory (DSmT) framework, in order to overcome the limitations of current approaches, i.e., the lack of precision in the final results of linguistic information fusion according to 1-Tuple representation ( q1 )- The linguistic information which expresses the expert's qualitative beliefs is expressed by means of mixed 2 Tuples (equidistant linguistic labels with a numeric biased value). Together with the 2-Tuple representation model, some basic operators are presented to carry out the fusion operation among qualitative information sources. At last, through simple example how 2-Tuple qualitative DSmT-based (q2 DSmT) fusion rules can be used for qualitative reasoning and fusion under uncertainty, which advantage is also showed by comparing with other methods.展开更多
This paper presented a game theoretic model to study the competition for a single investment oppertunity under uncertainty. It models the hazard rate of investment as a function of competitors' trigger level. Unde...This paper presented a game theoretic model to study the competition for a single investment oppertunity under uncertainty. It models the hazard rate of investment as a function of competitors' trigger level. Under uncertainty and different information structure, the option and game theory was applied to researching the optimal Nash equilibrium strategies of one or more firm. By means of Matlab software, the paper simulates a real estate developing project example and illustrates how parameter affects investment strategies. The paper's work will contribute to the present investment practice in China.展开更多
With the deepening of climate change research, more attention has been paid to vulnerability to climate change. Compared with water resources, forests and other natural ecosystems, agriculture is more vulnerable to cl...With the deepening of climate change research, more attention has been paid to vulnerability to climate change. Compared with water resources, forests and other natural ecosystems, agriculture is more vulnerable to climate change, thereby scientifically assessing agricultural vulnerability to climate change is of great significance to the formulation of rational and effective adaptation strategies. In this paper, the authors give a comprehensive review of the research from the perspective of the definition of climate change vulnerability and agricultural vulnerability to climate change, research topics, and evaluation methodologies. Existing problems in current research, including scenario application, methods, and uncertainties, are analyzed, and meanwhile, a vision of the direction for future research in assessment of agricultural vulnerability is also presented.展开更多
The effect of uncertainty about stochastic diffusion model on dynamic portfolio choice of an investor who maximizes utility of terminal portfolio wealth was studied.It applied stochastic control method to obtain the c...The effect of uncertainty about stochastic diffusion model on dynamic portfolio choice of an investor who maximizes utility of terminal portfolio wealth was studied.It applied stochastic control method to obtain the closed-form solution of optimal dynamic portfolio,and used the Bayesian rule to estimate the model parameters to do an empirical study on two different samples of Shanghai Exchange Composite Index.Results show,model uncertainty results in positive or negative hedging demand of portfolio,which depends on investor's attitude toward risk;the effect of model uncertainty is more significant with the increasing of investment horizon,the decreasing of investor's risk-aversion degree,and the decreasing of information;predictability of risky asset return increases its allocation in portfolio,at the same time,the effect of model uncertainty also strengthens.展开更多
There have long been arguments about the impact of urbanization on local meteorological observations. This letter reviews up-to-date studies of the urbanization-related warming in the observed land surface air tempera...There have long been arguments about the impact of urbanization on local meteorological observations. This letter reviews up-to-date studies of the urbanization-related warming in the observed land surface air temperature series in China. Many previous studies have suggested that, over the past few decades, the local warming due to urbanization could have been about 0.1 °C/10 yr, or even larger. However, based on recently developed homogenized temperature records, the estimated urban bias is smaller. Major uncertainties arise from either the data quality or the techniques used to estimate the urbanization effect. A key example is the ‘observationminus-reanalysis' method, which tends to overestimate the urban signal in this region, partly due to systematic bias in the multi-decadal variability of surface air temperature in the reanalysis data. It is expected that improved numerical modeling with high-resolution information regarding the changing land surface in the region will help to further understand and quantify the effect of urbanization in local temperature records.展开更多
The income approach of asset valuation estimates the asset value according to the asset-discounted future earnings or the capitalizing process. As a result, a reasonable prediction of asset-expected future returns has...The income approach of asset valuation estimates the asset value according to the asset-discounted future earnings or the capitalizing process. As a result, a reasonable prediction of asset-expected future returns has become one of the core contents of the income approach. The forecast on expected future earnings is generally based on many uncertain factors, such as strict conditions of assumption and the complexity of environment. However, the current valuation practice in this aspect varies greatly and sometimes depends on personally experienced judgment of appraisers. Therefore, the obtained valuation results tend to be simplified and absolutized. This paper takes a listed company in China as an example to explore the way of inserting an uncertainty analysis into the prediction of the income approach, and then to obtain a series of valuation results within a certain probability fluctuation range. Finally, it puts forward some suggestions about the Monte Carlo simulation (MCS).展开更多
Genetic diversity study of wild Philippine paddy straw mushroom (Volvariella volvacea) was conducted to establish a germplasm collection accessible to volvariella producers in the Philippines. Forty one wild strains...Genetic diversity study of wild Philippine paddy straw mushroom (Volvariella volvacea) was conducted to establish a germplasm collection accessible to volvariella producers in the Philippines. Forty one wild strains were collected from different geographical areas in Northern and Central Luzon region. Strains were differentiated using random amplified polymorphic DNA (RAPD). A single 10-based primer was used to generate randomly amplified polymorphic DNA (RAPD) in V. volvacea and differences were noted in band size (bp) ranging from 1,800 bp to 550 bp. Principal component analysis (PCA) of the RAPD data revealed 4 groups from wild strains. One strain showed RAPD pattern with band appearance at 1,750, 950 and 750 bp; 3 strains at 1,800 and 750 bp; 8 strains at 1,500 and 550; and the most abundant group with 29 strains at 750 bp. With observed lack of heterogeneity among strains, it is recommended that more collections from the wild should be undertaken for more diverse germplasm collection. Moreover, it is suggested that RAPD can be used to delineate strains of V. volvacea with potential importance on genetic diversity conservation and breeding.展开更多
Directional drilling has been established in the coal industry as a viable means of gas drainage, exploration and water management. But the environment in and around coal seams is not always conducive to stable condit...Directional drilling has been established in the coal industry as a viable means of gas drainage, exploration and water management. But the environment in and around coal seams is not always conducive to stable conditions while drilling and borehole stability after the drilling has been completed. This paper identifies the conditions which cause unstable drilling conditions and the various means which are used to attempt to manage or bypass those conditions. Ultimately, equipment does become bogged in these adverse environments and requires recovery by over-coring.展开更多
Service composition is considered to be an effective way for resource sharing and node collaboration in Mobile Ad hoc NETworks (MANETs) environment.In order to improve the reliability and shorten the response time of ...Service composition is considered to be an effective way for resource sharing and node collaboration in Mobile Ad hoc NETworks (MANETs) environment.In order to improve the reliability and shorten the response time of composite services,this paper first analyzes the node environments and network environments that affect the component services' availability,and then proposes an Environment-aware Quantitative Evaluation Model for Service Availability (EQEM-SA).In addition,based on EQEM-SA,a service field concept is proposed as well as the availability attenuation equation,where the availability value is considered as the field strength.Then the service selection approach based on service field model is presented.The effectiveness of the proposed approach is illustrated and compared with related references,and the results of experimental evaluations indicate that our approach significantly reduces the failure rate and shortens the service delay.展开更多
Human resource is already in society today one of the most important resources, the human resources stability has important implications, university should how to its important role and how to keep its stability, in t...Human resource is already in society today one of the most important resources, the human resources stability has important implications, university should how to its important role and how to keep its stability, in this thesis are introduced. In addition, concerning human resources loss and its have also means have relevant instruction, how to understand university human resources of stability,handled the problem, the university can better, faster development.展开更多
Under the background of accelerated integrated urban-rural development, this paper offers an analysis on the short-term employment of rural migrants in China and resulting wage gap between long-term and short-term rur...Under the background of accelerated integrated urban-rural development, this paper offers an analysis on the short-term employment of rural migrants in China and resulting wage gap between long-term and short-term rural migrants. On the basis of correcting for sample selection problems arising from labor market participation and short-term employment, rural migrants' wage function is estimated using quantile regression method, and wage gap between long-term and short-term rural migrants is decomposed using MM method. Our empirical results suggest that those with a higher level of education, training experience and local employment recommended by family relations or in formal labor market are more likely to secure long-term labor contract," region and education have significant contributions to the wage of rural migrants," rural migrants of both long- and short-term contract types have great gaps at the bottom of salary distribution; and there exists a sticky floor effect in wage difference of rural migrants. These results have important policy implications in enhancing employment stability of rural migrants, improving income distribution equity, speeding up the process of urbanization, and balancing regional development.展开更多
This research develops a comprehensive method to solve a combinatorial problem consisting of distribution system reconfiguration, capacitor allocation, and renewable energy resources sizing and siting simultaneously a...This research develops a comprehensive method to solve a combinatorial problem consisting of distribution system reconfiguration, capacitor allocation, and renewable energy resources sizing and siting simultaneously and to improve power system's accountability and system performance parameters. Due to finding solution which is closer to realistic characteristics, load forecasting, market price errors and the uncertainties related to the variable output power of wind based DG units are put in consideration. This work employs NSGA-II accompanied by the fuzzy set theory to solve the aforementioned multi-objective problem. The proposed scheme finally leads to a solution with a minimum voltage deviation, a maximum voltage stability, lower amount of pollutant and lower cost. The cost includes the installation costs of new equipment, reconfiguration costs, power loss cost, reliability cost, cost of energy purchased from power market, upgrade costs of lines and operation and maintenance costs of DGs. Therefore, the proposed methodology improves power quality, reliability and security in lower costs besides its preserve, with the operational indices of power distribution networks in acceptable level. To validate the proposed methodology's usefulness, it was applied on the IEEE 33-bus distribution system then the outcomes were compared with initial configuration.展开更多
We conduct uncertain analysis of micro agricultural project, including the break-even analysis of single product micro agricultural project, the boundary break-even points analysis of the double product micro agricult...We conduct uncertain analysis of micro agricultural project, including the break-even analysis of single product micro agricultural project, the boundary break-even points analysis of the double product micro agricultural project. We find out the critical point and the critical line of the break-everL We analyze the ability to resist risk. This analyses help the micro agricultural project's investors to price reasonably, forecast the earnings and make the correct decision.展开更多
The Rosenzweig-Macarthur Model is used to partially explain Venture Capital investment cycles. Investment opportunities and the experience of the investors, represent the prey and predator respectively. Stability anal...The Rosenzweig-Macarthur Model is used to partially explain Venture Capital investment cycles. Investment opportunities and the experience of the investors, represent the prey and predator respectively. Stability analysis with respect to the interior equilibrium point is performed and dynamics of the system are investigated using numerical simulations and results are presented. The model shows that parameter variation affects the stability of the system and it experiences bifurcations. The results show that stability analysis is useful to provide a Venture Capitalist with the stability ranges of parameters in the system, to improve the quality of the investment process.展开更多
When a small and medium-sized enterprise (SME) decides to invest in an innovative project, it becomes attached to a high level of uncertainty (Hall & Lerner, 2009) and it could meet some financial constraints (K...When a small and medium-sized enterprise (SME) decides to invest in an innovative project, it becomes attached to a high level of uncertainty (Hall & Lerner, 2009) and it could meet some financial constraints (Kerr & Nanda, 2014). This work is trying to apprehend the specific financial problems which SMEs, working on innovative projects, might face in a context characterized by a lack of liquidity, and it aims to improve the understanding of previous theoretical and empirical studies that dealt with the subject of financing these innovative companies. Moreover, it appears that it is important to ask the following question: Are there specific financial constraints to innovative SMEs? In order to answer the preceding question, this paper presents firstly the concept of innovation within companies. Secondly, it describes the specificities bound to the diverse financing approaches: in terms of risk, uncertainty, asymmetric information and profitability of an innovative project, while developing a theoretical approach concerning the possible constraints of financing the innovative companies.展开更多
The study discusses accuracy evaluation methods for offshore wind energy resources by using scatterometer SeaWinds-derived wind speed and Weibull parameters. The purpose of this study is to evaluate accuracies of SeaW...The study discusses accuracy evaluation methods for offshore wind energy resources by using scatterometer SeaWinds-derived wind speed and Weibull parameters. The purpose of this study is to evaluate accuracies of SeaWinds-derived Weibull mean wind speed and energy density by considering uncertainties inherent in SeaWinds wind speed estimates. In this study, 1159 SeaWinds-derived wind speeds covering the KEO buoy are used for estimating two Weibull parameters, scale and shape. On the other hand, observed wind speeds from 2004 to 2008 at the KEO buoy are used for simulating three kinds of wind speeds in order to quantify some uncertainties inherent in SeaWinds-derived wind speeds. It is found that uncertainties associated with wind speed estimates (operational wind speed range, sampling time) show small differences in scale, shape and Weibull mean wind speed except energy density among the simulated datasets. Furthermore, the upper and lower bounds of 90% confidence interval corresponding to SeaWinds number of observations indicate 4-2.5% error of Weibull mean wind speed and 4-6.8% error of energy density, respectively.展开更多
基金Supported by Special Fund for Bagui Scholars of Guangxi Zhuang Autonomous RegionNational Science and Technology Support Program of China (2012BAD40B04,2013BAD01B02-17)+3 种基金Project for Scientific Research and Technological Development of Guangxi Zhuang Autonomous Region (GKG1123001-3C)Youth Fund of Guangxi Zhuang Autonomous Region(2013GXNSFBA019052,2013GXNSFAA019054)Fund for Science and Technology Development of Guangxi Academy of Agricultural Sciences(GNK2014JQ13)Special Fund for Basic Scientific Research of Guangxi Academy of Agricultural Sciences(2013YT05)~~
文摘This study aimed to screen drought stress indicators and analyze the drought resistance in 105 cultivated rice germplasm resources in Guangxi Zhuang Autonomous Region under drought stress in the whole growth period based on D value of seven morphological traits including panicle neck thickness,effective panicle number per plant,1 000-grain weight,filled grain number per panicle,total grain number,seed setting rate and yield per plant.According to the results,under drought stress,yield per plant exhibited significant positive correlation with panicle neck thickness and exhibited extremely significant positive correlation with other five morphological traits.Based on the identification and evaluation of comprehensive drought-resistance index D value,seven highly drought-resistant cultivated rice varieties were screened,accounting for 6.67%.Upland rice germplasm resources in Guangxi Zhuang Autonomous Region possess strong drought-resistance capacity,which could be used to screen highly drought-resistant rice germplasm materials.This study provided material basis and theoretical reference for breeding drought resistant rice cultivars in Guangxi Zhuang Autonomous Region.
文摘Through field observation and lab analysis, 13 agronomic traits, including plant height and effective branching number per plant, etc., of 207 faba bean (Vicia faba L.) germplasms saved in Crop Middle-term Genebank of Hubei Province were evaluated, moreover, the identification on the disease resistance and the quality was carried out on parts of germplasm resources. The results showed that the faba beangermplasm resources in Hubei Province were abundant, the variation range of agronomic traits like the growth period, plant height and 100-bean weight, etc., was great, and the range of choice was wide. In the aspect of quality, there were 9 germplasms withthe content of crude protein higher than 30%, and the variation range of amylose content in total starch was large, which provided excellent sources of parents for breedinq hi.qh-quality faba bean varieties in Hubei Province.
基金Project (Nos. 60084003,70171056) supported by the National Natural Science Foundation of China
文摘This study focuses on revealing the relationship between uncertainty and investment probability through real option model involving investment critical trigger and project earning. Use of Matlab software on the experimental results showing that project earning volatility influences investment probability, led the authors to conclude that this notion is not always correct, as increasing uncertainty should have an inhibiting effect on investment, and that in certain situation, increasing uncertainty actually increases the investment probability and so, should have positive impact on investment.
基金Supported by the National Natural Science Foundation of China (60804063)863 Program (2006AA040202)
文摘Most of modern systems for information retrieval, fusion and management have to deal with more and more qualitative information (by linguistic labels) besides information expressed quantitatively (by numbers), since human reports are better and easier expressed in natural language than with numbers. In this paper, Herrera-Martfnez's 2-Tuple linguistic representation model is extended for reasoning with uncertain and qualitative information in Dezert-Smarandache Theory (DSmT) framework, in order to overcome the limitations of current approaches, i.e., the lack of precision in the final results of linguistic information fusion according to 1-Tuple representation ( q1 )- The linguistic information which expresses the expert's qualitative beliefs is expressed by means of mixed 2 Tuples (equidistant linguistic labels with a numeric biased value). Together with the 2-Tuple representation model, some basic operators are presented to carry out the fusion operation among qualitative information sources. At last, through simple example how 2-Tuple qualitative DSmT-based (q2 DSmT) fusion rules can be used for qualitative reasoning and fusion under uncertainty, which advantage is also showed by comparing with other methods.
文摘This paper presented a game theoretic model to study the competition for a single investment oppertunity under uncertainty. It models the hazard rate of investment as a function of competitors' trigger level. Under uncertainty and different information structure, the option and game theory was applied to researching the optimal Nash equilibrium strategies of one or more firm. By means of Matlab software, the paper simulates a real estate developing project example and illustrates how parameter affects investment strategies. The paper's work will contribute to the present investment practice in China.
基金supported by the China Meteorological Administration(NoGYHY200806008)the China-UK -Swiss ACCC Project
文摘With the deepening of climate change research, more attention has been paid to vulnerability to climate change. Compared with water resources, forests and other natural ecosystems, agriculture is more vulnerable to climate change, thereby scientifically assessing agricultural vulnerability to climate change is of great significance to the formulation of rational and effective adaptation strategies. In this paper, the authors give a comprehensive review of the research from the perspective of the definition of climate change vulnerability and agricultural vulnerability to climate change, research topics, and evaluation methodologies. Existing problems in current research, including scenario application, methods, and uncertainties, are analyzed, and meanwhile, a vision of the direction for future research in assessment of agricultural vulnerability is also presented.
基金Key program of Natural Science Research of High Education of Anhui Province of China(No.KJ2009A157)
文摘The effect of uncertainty about stochastic diffusion model on dynamic portfolio choice of an investor who maximizes utility of terminal portfolio wealth was studied.It applied stochastic control method to obtain the closed-form solution of optimal dynamic portfolio,and used the Bayesian rule to estimate the model parameters to do an empirical study on two different samples of Shanghai Exchange Composite Index.Results show,model uncertainty results in positive or negative hedging demand of portfolio,which depends on investor's attitude toward risk;the effect of model uncertainty is more significant with the increasing of investment horizon,the decreasing of investor's risk-aversion degree,and the decreasing of information;predictability of risky asset return increases its allocation in portfolio,at the same time,the effect of model uncertainty also strengthens.
基金supported by the National Natural Science Foundation of China[grant number 41475078]Strategic Priority Research Program–Climate Change:Carbon Budget and Relevant Issues of the Chinese Academy of Sciences[grant number XDA05090105]
文摘There have long been arguments about the impact of urbanization on local meteorological observations. This letter reviews up-to-date studies of the urbanization-related warming in the observed land surface air temperature series in China. Many previous studies have suggested that, over the past few decades, the local warming due to urbanization could have been about 0.1 °C/10 yr, or even larger. However, based on recently developed homogenized temperature records, the estimated urban bias is smaller. Major uncertainties arise from either the data quality or the techniques used to estimate the urbanization effect. A key example is the ‘observationminus-reanalysis' method, which tends to overestimate the urban signal in this region, partly due to systematic bias in the multi-decadal variability of surface air temperature in the reanalysis data. It is expected that improved numerical modeling with high-resolution information regarding the changing land surface in the region will help to further understand and quantify the effect of urbanization in local temperature records.
文摘The income approach of asset valuation estimates the asset value according to the asset-discounted future earnings or the capitalizing process. As a result, a reasonable prediction of asset-expected future returns has become one of the core contents of the income approach. The forecast on expected future earnings is generally based on many uncertain factors, such as strict conditions of assumption and the complexity of environment. However, the current valuation practice in this aspect varies greatly and sometimes depends on personally experienced judgment of appraisers. Therefore, the obtained valuation results tend to be simplified and absolutized. This paper takes a listed company in China as an example to explore the way of inserting an uncertainty analysis into the prediction of the income approach, and then to obtain a series of valuation results within a certain probability fluctuation range. Finally, it puts forward some suggestions about the Monte Carlo simulation (MCS).
文摘Genetic diversity study of wild Philippine paddy straw mushroom (Volvariella volvacea) was conducted to establish a germplasm collection accessible to volvariella producers in the Philippines. Forty one wild strains were collected from different geographical areas in Northern and Central Luzon region. Strains were differentiated using random amplified polymorphic DNA (RAPD). A single 10-based primer was used to generate randomly amplified polymorphic DNA (RAPD) in V. volvacea and differences were noted in band size (bp) ranging from 1,800 bp to 550 bp. Principal component analysis (PCA) of the RAPD data revealed 4 groups from wild strains. One strain showed RAPD pattern with band appearance at 1,750, 950 and 750 bp; 3 strains at 1,800 and 750 bp; 8 strains at 1,500 and 550; and the most abundant group with 29 strains at 750 bp. With observed lack of heterogeneity among strains, it is recommended that more collections from the wild should be undertaken for more diverse germplasm collection. Moreover, it is suggested that RAPD can be used to delineate strains of V. volvacea with potential importance on genetic diversity conservation and breeding.
文摘Directional drilling has been established in the coal industry as a viable means of gas drainage, exploration and water management. But the environment in and around coal seams is not always conducive to stable conditions while drilling and borehole stability after the drilling has been completed. This paper identifies the conditions which cause unstable drilling conditions and the various means which are used to attempt to manage or bypass those conditions. Ultimately, equipment does become bogged in these adverse environments and requires recovery by over-coring.
基金supported in part by the National Key Basic Research Program of China(Grant Nos.2009CB320406and2009CB320504)Foundation for Innovative Research Groups of the National Natural Science Foundation of China(Grant No.60821001)National Natural Science Foundation of China(Grant No.61070206)
文摘Service composition is considered to be an effective way for resource sharing and node collaboration in Mobile Ad hoc NETworks (MANETs) environment.In order to improve the reliability and shorten the response time of composite services,this paper first analyzes the node environments and network environments that affect the component services' availability,and then proposes an Environment-aware Quantitative Evaluation Model for Service Availability (EQEM-SA).In addition,based on EQEM-SA,a service field concept is proposed as well as the availability attenuation equation,where the availability value is considered as the field strength.Then the service selection approach based on service field model is presented.The effectiveness of the proposed approach is illustrated and compared with related references,and the results of experimental evaluations indicate that our approach significantly reduces the failure rate and shortens the service delay.
文摘Human resource is already in society today one of the most important resources, the human resources stability has important implications, university should how to its important role and how to keep its stability, in this thesis are introduced. In addition, concerning human resources loss and its have also means have relevant instruction, how to understand university human resources of stability,handled the problem, the university can better, faster development.
文摘Under the background of accelerated integrated urban-rural development, this paper offers an analysis on the short-term employment of rural migrants in China and resulting wage gap between long-term and short-term rural migrants. On the basis of correcting for sample selection problems arising from labor market participation and short-term employment, rural migrants' wage function is estimated using quantile regression method, and wage gap between long-term and short-term rural migrants is decomposed using MM method. Our empirical results suggest that those with a higher level of education, training experience and local employment recommended by family relations or in formal labor market are more likely to secure long-term labor contract," region and education have significant contributions to the wage of rural migrants," rural migrants of both long- and short-term contract types have great gaps at the bottom of salary distribution; and there exists a sticky floor effect in wage difference of rural migrants. These results have important policy implications in enhancing employment stability of rural migrants, improving income distribution equity, speeding up the process of urbanization, and balancing regional development.
文摘This research develops a comprehensive method to solve a combinatorial problem consisting of distribution system reconfiguration, capacitor allocation, and renewable energy resources sizing and siting simultaneously and to improve power system's accountability and system performance parameters. Due to finding solution which is closer to realistic characteristics, load forecasting, market price errors and the uncertainties related to the variable output power of wind based DG units are put in consideration. This work employs NSGA-II accompanied by the fuzzy set theory to solve the aforementioned multi-objective problem. The proposed scheme finally leads to a solution with a minimum voltage deviation, a maximum voltage stability, lower amount of pollutant and lower cost. The cost includes the installation costs of new equipment, reconfiguration costs, power loss cost, reliability cost, cost of energy purchased from power market, upgrade costs of lines and operation and maintenance costs of DGs. Therefore, the proposed methodology improves power quality, reliability and security in lower costs besides its preserve, with the operational indices of power distribution networks in acceptable level. To validate the proposed methodology's usefulness, it was applied on the IEEE 33-bus distribution system then the outcomes were compared with initial configuration.
文摘We conduct uncertain analysis of micro agricultural project, including the break-even analysis of single product micro agricultural project, the boundary break-even points analysis of the double product micro agricultural project. We find out the critical point and the critical line of the break-everL We analyze the ability to resist risk. This analyses help the micro agricultural project's investors to price reasonably, forecast the earnings and make the correct decision.
文摘The Rosenzweig-Macarthur Model is used to partially explain Venture Capital investment cycles. Investment opportunities and the experience of the investors, represent the prey and predator respectively. Stability analysis with respect to the interior equilibrium point is performed and dynamics of the system are investigated using numerical simulations and results are presented. The model shows that parameter variation affects the stability of the system and it experiences bifurcations. The results show that stability analysis is useful to provide a Venture Capitalist with the stability ranges of parameters in the system, to improve the quality of the investment process.
文摘When a small and medium-sized enterprise (SME) decides to invest in an innovative project, it becomes attached to a high level of uncertainty (Hall & Lerner, 2009) and it could meet some financial constraints (Kerr & Nanda, 2014). This work is trying to apprehend the specific financial problems which SMEs, working on innovative projects, might face in a context characterized by a lack of liquidity, and it aims to improve the understanding of previous theoretical and empirical studies that dealt with the subject of financing these innovative companies. Moreover, it appears that it is important to ask the following question: Are there specific financial constraints to innovative SMEs? In order to answer the preceding question, this paper presents firstly the concept of innovation within companies. Secondly, it describes the specificities bound to the diverse financing approaches: in terms of risk, uncertainty, asymmetric information and profitability of an innovative project, while developing a theoretical approach concerning the possible constraints of financing the innovative companies.
文摘The study discusses accuracy evaluation methods for offshore wind energy resources by using scatterometer SeaWinds-derived wind speed and Weibull parameters. The purpose of this study is to evaluate accuracies of SeaWinds-derived Weibull mean wind speed and energy density by considering uncertainties inherent in SeaWinds wind speed estimates. In this study, 1159 SeaWinds-derived wind speeds covering the KEO buoy are used for estimating two Weibull parameters, scale and shape. On the other hand, observed wind speeds from 2004 to 2008 at the KEO buoy are used for simulating three kinds of wind speeds in order to quantify some uncertainties inherent in SeaWinds-derived wind speeds. It is found that uncertainties associated with wind speed estimates (operational wind speed range, sampling time) show small differences in scale, shape and Weibull mean wind speed except energy density among the simulated datasets. Furthermore, the upper and lower bounds of 90% confidence interval corresponding to SeaWinds number of observations indicate 4-2.5% error of Weibull mean wind speed and 4-6.8% error of energy density, respectively.