The performance of corporate social responsibility is conducive to the con- tinuous improvement of their profitability, and promotes the upgrading of corporation value. However, it is difficult to confirm, calculate a...The performance of corporate social responsibility is conducive to the con- tinuous improvement of their profitability, and promotes the upgrading of corporation value. However, it is difficult to confirm, calculate and check the costs and benefits brought by the implementation of corporate social responsibility under the current ac- counting theory system, so it is difficult to estimate whether the fulfillment of corpo- rate social responsibility has any effects on the corporation value assessment. Therefore, based on corporate social responsibility, the correction mode of corpora- tion value assessment is put forward.展开更多
Tunnel water inrush is one of the common geological disasters in the underground engineering construction.In order to effectively evaluate and control the occurrence of water inrush,the risk assessment model of tunnel...Tunnel water inrush is one of the common geological disasters in the underground engineering construction.In order to effectively evaluate and control the occurrence of water inrush,the risk assessment model of tunnel water inrush was proposed based on improved attribute mathematical theory.The trigonometric functions were adopted to optimize the attribute mathematical theory,avoiding the influence of mutation points and linear variation zones in traditional linear measurement functions on the accuracy of the model.Based on comprehensive analysis of various factors,five parameters were selected as the evaluation indicators for the model,including tunnel head pressure,permeability coefficient of surrounding rock,crushing degree of surrounding rock,relative angle of joint plane and tunnel section size,under the principle of dimension rationality,independence,directness and quantification.The indicator classifications were determined.The links among measured data were analyzed in detail,and the objective weight of each indicator was determined by using similar weight method.Thereby the tunnel water inrush risk assessment model is established and applied in four target segments of two different tunnels in engineering.The evaluation results and the actual excavation data agree well,which indicates that the model is of high credibility and feasibility.展开更多
In this study, a risk-based management model is developed and applied to an industrial zone. The models proposed by the United States Environmental Protection Agency and Han Bing have been improved by adding a residua...In this study, a risk-based management model is developed and applied to an industrial zone. The models proposed by the United States Environmental Protection Agency and Han Bing have been improved by adding a residual ratio of volatile organic compounds (VOC) after boiling and deleting the related parameters in half-life. Using this improved model, an integrated process was used to assess human health risk level in the study area. Compared with water quality analysis, the results highlight the importance of applying an integrated approach for decision making on risk levels and water protection. The results of this study demonstrated that: (1) Compared with these permissible level standards in China (GB 3838-2002) and National Primary Drinking Water Regulations of the United States, the residents' daily life had not been affected by the groundwater in this area (except for relative bad water quality of HB3-4 and HB3-6); (2) The typical detected organic contaminants of all groundwater samples were chloroform, carbon tetrachloride, trichloroethylene and tetrachloroethene, and the pollution sources were mainly industrial sources by preliminary investigations; (3) As for groundwater, the non-carcinogenic risk values of all samples do not exceed the permissible level of 1.0 and the carcinogenic risk values are relatively lower than the permissible level of 1.00E-06 to 1.00E-04; (4) Drinking water pathway of trichloroethylene and tetrachloroethylene mainly contribute to increasing the health risk of residents' in study areas; (5) In terms of non-carcinogenic risk and carcinogenic risk, the health risk order for drinking water pathway and dermal contact pathway was: drinking water pathway 〉 dermal contact pathway.展开更多
With the development of EMC technology, EMC assessment has become increasingly important in EMC design. Although numerous EMC assessment models are available today, few of them can provide a tradeoff between efficienc...With the development of EMC technology, EMC assessment has become increasingly important in EMC design. Although numerous EMC assessment models are available today, few of them can provide a tradeoff between efficiency and accuracy for the specific case of military vehicular communication systems. Face to this situation, a modified four-level assessment model is proposed in the paper. First, the development of EMC assessment technology is briefly reviewed, and the theoretical mechanism of EMI environment is introduced. Then, the architecture of the proposed model is outlined, and the assessment methods are explored. To demonstrate the application of it, an example involving a communication system in a military vehicle is presented. From the physical layer to the signal layer, a hierarchical assessment on the entire system is successfully performed based on the proposed model, and we can make a qualitative EMC assessment on the EMC performance of the system. Based on a comparison with the traditional model, we conclude that the proposed model is more accurate, more efficient and less time-consuming, which is suitable for the EMC assessment on militaryvehicular communication systems. We hope that the proposed model will serve as a useful reference for system-level EMC assessments for other systems.展开更多
To the potential oil-spill risk caused by offshore pipeline more attention has been paid after the Dalian oil spill incident from oil-pipeline explosion. Since then an issue about how to prevent and control the sudden...To the potential oil-spill risk caused by offshore pipeline more attention has been paid after the Dalian oil spill incident from oil-pipeline explosion. Since then an issue about how to prevent and control the sudden oil-spill from the offshore pipeline has been raised. In this paper, we proposed an optimized model to analyze the main causes(probability) of spill and the consequence with the fuzzy comprehensive assessment model. Considering the complicated assessment process for oil-spill, the assessment factor system involving the spill probability and consequence was established based on the operative manual and statistic leakage/damage data of offshore pipeline in order to estimate the integrated spill risk score automatically. The evaluated factors of spill probability could be grouped into five aspects: corrosion, fatigue, national damage, third party, and operational fault; the consequence evaluated factors of spill included hazard of oil and impact-controlling capability. With some modifications based on experts' opinions, each of the evaluated factors in our work was developed with a relative weight and evaluation criterion. A test example for an offshore pipeline in the Bohai waters was described to show how the model can be used for an actual case in more detail. By using the oil-spill risk assessment model, it is easy to determine the risk level associated with the ongoing activity and management level and hence to take the risk mitigation action immediately.展开更多
This paper addresses the problem of assessing and optimizing the acoustic positioning system for underwater target localization with range measurement.We present a new three-dimensional assessment model to evaluate th...This paper addresses the problem of assessing and optimizing the acoustic positioning system for underwater target localization with range measurement.We present a new three-dimensional assessment model to evaluate the optimal geometric beacon formation whether meets user requirements.For mathematical tractability,it is assumed that the measurements of the range between the target and beacons are corrupted with white Gaussian noise with variance,which is distance-dependent.Then,the relationship between DOP parameters and positioning accuracy can be derived by adopting dilution of precision(DOP)parameters in the assessment model.In addition,the optimal geometric beacon formation yielding the best performance can be achieved via minimizing the values of geometric dilution of precision(GDOP)in the case where the target position is known and fixed.Next,in order to ensure that the estimated positioning accuracy on the region of interest satisfies the precision required by the user,geometric positioning accuracy(GPA),horizontal positioning accuracy(HPA)and vertical positioning accuracy(VPA)are utilized to assess the optimal geometric beacon formation.Simulation examples are designed to illustrate the exactness of the conclusion.Unlike other work that only uses GDOP to optimize the formation and cannot assess the performance of the specified size,this new three-dimensional assessment model can evaluate the optimal geometric beacon formation for each dimension of any point in three-dimensional space,which can provide guidance to optimize the performance of each specified dimension.展开更多
AIM: To set up a mathematic model for gastric cancer screening and to evaluate its function in mass screening for gastric cancer.METHODS: A case control study was carried on in 66patients and 198 normal people, then t...AIM: To set up a mathematic model for gastric cancer screening and to evaluate its function in mass screening for gastric cancer.METHODS: A case control study was carried on in 66patients and 198 normal people, then the risk and protective factors of gastric cancer were determined, including heavy manual work, foods such as small yellow-fin tuna, dried small shrimps, squills, crabs, mothers suffering from gastric diseases, spouse alive, use of refrigerators and hot food,etc. According to some principles and methods of probability and fuzzy mathematics, a quantitative assessment model was established as follows: first, we selected some factors significant in statistics, and calculated weight coefficient for each one by two different methods; second, population space was divided into gastric cancer fuzzy subset and non gastric cancer fuzzy subset, then a mathematic model for each subset was established, we got a mathematic expression of attribute degree (AD).RESULTS: Based on the data of 63 patients and 693 normal people, AD of each subject was calculated. Considering the sensitivity and specificity, the thresholds of AD values calculated were configured with 0.20 and 0.17, respectively.According to these thresholds, the sensitivity and specificity of the quantitative model were about 69% and 63%.Moreover, statistical test showed that the identification outcomes of these two different calculation methods were identical (P>0.05).CONCLUSION: The validity of this method is satisfactory.It is convenient, feasible, economic and can be used to determine individual and population risks of gastric cancer.展开更多
Smoke is the main cause of fire death. In order to minimize the potential danger of smoke hazard, a rational VR based fire training simulator should fully consider all aspects of smoke hazard. In the simulator, the vi...Smoke is the main cause of fire death. In order to minimize the potential danger of smoke hazard, a rational VR based fire training simulator should fully consider all aspects of smoke hazard. In the simulator, the visualization of data based on FDS (Fire Dynamics Simulator) and FED fire dynamic data and volume rendering is further optimized, which can be effectively and quickly applied to virtual fire protection. In addition, a comprehensive smoke hazard assessment model based on FED and FED is established to assess the IHD value of different paths, which represents the safety of different paths, and can be used for evacuation or rescue in virtual training. Taking the case of campus fire drill as an experiment, the research shows the accuracy and effectiveness of smoke assessment based on FDS and FED model. The road force with the highest safety can be selected through the comprehensive model. So the assessment model is proved to be valuable.展开更多
The characteristics of the financing model are firstly analyzed when the e-commerce enterprises participate in the supply chain finance. Internet supply chain finance models are divided into three categories with the ...The characteristics of the financing model are firstly analyzed when the e-commerce enterprises participate in the supply chain finance. Internet supply chain finance models are divided into three categories with the standard of whether the Electronic commerce enterprises provide funds for small and medium enterprises instead of banks. And then we further study the financing process and the functions of the e-commerce platform with specific examples. Finally, combined with the characteristics of the supply chain finance model, we set up a small and medium enterprises credit evaluation model based on the principle of variable weight with its dynamic data. At the same time, a multi time points and multi indicators decision-making method based on the principle of variable weight is proposed and a specific example is presented. In this paper, the Multi-criteria decision-making model with the principle of variable weight has been used two times. At last, a typical case has been analyzed based on this model with a higher accuracy rate of credit risk assessment.展开更多
The influence derived from atmosphere transmitting of radar wave, in the application of high-resolution airborne Synthetic Aperture Radar (SAR) stereo positioning, may produce some phase errors, and eventually be intr...The influence derived from atmosphere transmitting of radar wave, in the application of high-resolution airborne Synthetic Aperture Radar (SAR) stereo positioning, may produce some phase errors, and eventually be introduced into positioning model. This paper described the principle of airborne SAR stereo positioning and the error sources of stereo positioning accuracy that arose from atmosphere transmitting, established a corresponding assess- ment model of atmosphere transmitting influence, and testified the model and the assessment principle taking the 1-m resolution airborne SAR images of Zigong City, Sichuan Province in China, as the test dataset. The test result has proved that the assessment model is reliable and reasonable. And, it has shown that the phase error arisen from time delay is the main error source during the atmosphere transmitting, which has much more influences on cross-track di- rection and introduces a stereo positioning error of about eight meters, but less on the along-track direction.展开更多
Now, a rapidly growing concern for the environmental protection and resource utilization has stimulated many new activities in the in dustrialized world for coping with urgent environmental problems created by the ste...Now, a rapidly growing concern for the environmental protection and resource utilization has stimulated many new activities in the in dustrialized world for coping with urgent environmental problems created by the steadily increasing consumption of industrial products. Increasingly stringent r egulations and widely expressed public concern for the environment highlight the importance of disposing solid waste generated from industrial and consumable pr oducts. How to efficiently recycle and tackle this problem has been a very impo rtant issue over the world. Designing products for recyclability is driven by environmental and economic goals. To obtain good recyclability, two measures can be adopted. One is better recycling strategy and technology; the other is design for recycling (DFR). The recycling strategies of products generally inclu de: reuse, service, remanufacturing, recycling of production scraps during the p roduct usage, recycle (separation first) and disposal. Recyclability assessment is a very important content in DFR. This paper first discusses the content of D FR and strategies and types related to products recyclability, and points out th at easy or difficult recyclability depends on the design phase. Then method and procedure of recyclability assessment based on ANN is explored in detail. The pr ocess consists of selection of the ANN input and output parameters, control of t he sample quality and construction and training of the neural network. At la st, the case study shows this method is simple and operative.展开更多
Dumping area capacity is mainly affected by the hydrodynamic process (tidal sediment, storm surge and wave, etc.) as well as the size and depth of dumping area. Based on three-dimensional ocean circulation model kno...Dumping area capacity is mainly affected by the hydrodynamic process (tidal sediment, storm surge and wave, etc.) as well as the size and depth of dumping area. Based on three-dimensional ocean circulation model known as FVCOM (Finite Volume Coast and Ocean Model) and the stochastic dynamic statistical analysis model, taking advantage of dumping ground topography evolution and dumping quantity, the author aims to discuss the influence of hydrodynamic processes and dumping activity so as to built a new model of ocean dumping area capacity. With the data of depth and dumped amount in the dumping area, the changes of bottom topographic which caused by tidal current under the natural condition based on the FVCOM hydrodynamic and sediment module, the author strive to analyze the statistical relation of the changes for dumping amount, tidal current and bottom topographic. Through real data to fit revision coefficient values, which will be regarded as topographic changes reference value affected by wave and storm surges. Thus taking this evaluation as the long-term changes in the dumping capacity. In the premise of setting up the threshold of bottom topographic changes, the dumping area capacity is calculated. Take Yangtze Estuary No. 1 dumping area as an example, As the water depth reduces by 0.5 m annually, the dumping area capacity is about 6.7 million m3/a, the model results are in reasonable agreement with the actual amount. Then the model is validated in Luoyuan Bay dumping area, Shengsishangchuan Mountain dumping area, Dongding dumping area, Dongshan dumping area, and Wenzhou Port dumoin~ area. it is turns out the results are similar to that of the actual observations.展开更多
With the acceleration of the construction of quantum communication networks,scholars have proposed different quantum communication protocols for different application scenarios.However,few scholars pay attention to th...With the acceleration of the construction of quantum communication networks,scholars have proposed different quantum communication protocols for different application scenarios.However,few scholars pay attention to the risk assessment process before communication.In this paper,we propose a novel quantum risk assessment model based on quantum teleportation technology with two three-qubit GHZ states.Only by using Bell states measurements(BSMs)and two-qubit projective measurements(PJMs),the communicators can recovery any arbitrary two-qubit state.This protocol can transmit two-dimension risk assessment factors with better security performance.On the one hand,more sufficient evaluation factors allow the two communicating parties to more objectively evaluate the risk level of communication with the other party,and on the other hand,it also improves the qubit efficiency of the protocol.Moreover,we introduce the third party in this scheme can be semi-trusted,which must be full-trusted in our previous work.This change can reduce the dependence of the communication parties on the third-party organization and improve the privacy of communication.The security analysis shows that this scheme can resist internal and external attacks,and the quantum circuit diagrams also prove that our protocol is physically easier to implement.展开更多
BACKGROUND Prediabetes risk assessment models derived from large sample sizes are scarce.AIM To establish a robust assessment model for prediabetes and to validate the model in different populations.METHODS The China ...BACKGROUND Prediabetes risk assessment models derived from large sample sizes are scarce.AIM To establish a robust assessment model for prediabetes and to validate the model in different populations.METHODS The China National Diabetes and Metabolic Disorders Study(CNDMDS)collected information from 47325 participants aged at least 20 years across China from 2007 to 2008.The Thyroid Disorders,Iodine Status and Diabetes Epidemiological Survey(TIDE)study collected data from 66108 participants aged at least 18 years across China from 2015 to 2017.A logistic model with stepwise selection was performed to identify significant risk factors for prediabetes and was internally validated by bootstrapping in the CNDMDS.External validations were performed in diverse populations,including populations of Hispanic(Mexican American,other Hispanic)and non-Hispanic(White,Black and Asian)participants in the National Health and Nutrition Examination Survey(NHANES)in the United States and 66108 participants in the TIDE study in China.C statistics and calibration plots were adopted to evaluate the model’s discrimination and calibration performance.RESULTS A set of easily measured indicators(age,education,family history of diabetes,waist circumference,body mass index,and systolic blood pressure)were selected as significant risk factors.A risk assessment model was established for prediabetes with a C statistic of 0.6998(95%CI:0.6933 to 0.7063)and a calibration slope of 1.0002.When externally validated in the NHANES and TIDE studies,the model showed increased C statistics in Mexican American,other Hispanic,Non-Hispanic Black,Asian and Chinese populations but a slightly decreased C statistic in non-Hispanic White individuals.Applying the risk assessment model to the TIDE population,we obtained a C statistic of 0.7308(95%CI:0.7260 to 0.7357)and a calibration slope of 1.1137.A risk score was derived to assess prediabetes.Individuals with scores≥7 points were at high risk of prediabetes,with a sensitivity of 60.19%and specificity of 67.59%.CONCLUSION An easy-to-use assessment model for prediabetes was established and was internally and externally validated in different populations.The model had a satisfactory performance and could screen individuals with a high risk of prediabetes.展开更多
Machine learning is currently one of the research hotspots in the field of landslide prediction.To clarify and evaluate the differences in characteristics and prediction effects of different machine learning models,Co...Machine learning is currently one of the research hotspots in the field of landslide prediction.To clarify and evaluate the differences in characteristics and prediction effects of different machine learning models,Conghua District,which is the most prone to landslide disasters in Guangzhou,was selected for landslide susceptibility evaluation.The evaluation factors were selected by using correlation analysis and variance expansion factor method.Applying four machine learning methods namely Logistic Regression(LR),Random Forest(RF),Support Vector Machines(SVM),and Extreme Gradient Boosting(XGB),landslide models were constructed.Comparative analysis and evaluation of the model were conducted through statistical indices and receiver operating characteristic(ROC)curves.The results showed that LR,RF,SVM,and XGB models have good predictive performance for landslide susceptibility,with the area under curve(AUC)values of 0.752,0.965,0.996,and 0.998,respectively.XGB model had the highest predictive ability,followed by RF model,SVM model,and LR model.The frequency ratio(FR)accuracy of LR,RF,SVM,and XGB models was 0.775,0.842,0.759,and 0.822,respectively.RF and XGB models were superior to LR and SVM models,indicating that the integrated algorithm has better predictive ability than a single classification algorithm in regional landslide classification problems.展开更多
This paper takes the assessment and evaluation of computational mechanics course as the background,and constructs a diversified course evaluation system that is student-centered and integrates both quantitative and qu...This paper takes the assessment and evaluation of computational mechanics course as the background,and constructs a diversified course evaluation system that is student-centered and integrates both quantitative and qualitative evaluation methods.The system not only pays attention to students’practical operation and theoretical knowledge mastery but also puts special emphasis on the cultivation of students’innovative abilities.In order to realize a comprehensive and objective evaluation,the assessment and evaluation method of the entropy weight model combining TOPSIS(Technique for Order Preference by Similarity to Ideal Solution)multi-attribute decision analysis and entropy weight theory is adopted,and its validity and practicability are verified through example analysis.This method can not only comprehensively and objectively evaluate students’learning outcomes,but also provide a scientific decision-making basis for curriculum teaching reform.The implementation of this diversified course evaluation system can better reflect the comprehensive ability of students and promote the continuous improvement of teaching quality.展开更多
Recent years have witnessed a rapid development of star-rated hotels in China, especially high- end star-rated hotels. Consequently, there are now approximately12 000 hotels in China. One bottleneck within the industr...Recent years have witnessed a rapid development of star-rated hotels in China, especially high- end star-rated hotels. Consequently, there are now approximately12 000 hotels in China. One bottleneck within the industry is its huge energy consumption and carbon emissions, but the development of a comprehensive energy consumption assessment has lagged. Here, a comprehensive energy consumption and carbon emission model suitable for hospitality is established, using comprehensive data collected for hotels over six years and with reference to general international methods, decomposition analysis methods as recommended by the IPCC, and related standards in China. Our study shows that the maximum comparable unit energy consumption per building area among four- and five-star hotels is 73.26 kg ce m-2 y-l. Through energy-saving reconstruction, the comprehensive energy consumption of five-star hotels has declined by 4.1% in six years and is smaller than the advanced comparable value of 55 kg ce m2 y4. The comparable unit energy consumption per area building of most two- and three-star hotels (53 kg ce m2 y-l) is higher than the reasonable value. There are large numbers of hotels of this type in China and the potential energy savings are huge. Analyzing factors of energy consumption, we found that indirect carbon emissions from electricity usage are the most significant. From an energy consumption structural perspective, Heating, Ventilation and Air Conditioning (HVAC) System accounts for most energy consumption. This research provides a foundation for further examination of energy-savings, emission reduction plans and Monitoring Reporting Verification (MRV) in the hospitality sector.展开更多
From the perspective of global economic general equilibrium, this study developed a new climate change IAM named CIECIA. The economic core of this IAM is a multi-country-sector general equilibrium model. The endogenou...From the perspective of global economic general equilibrium, this study developed a new climate change IAM named CIECIA. The economic core of this IAM is a multi-country-sector general equilibrium model. The endogenous technology progress mode is introduced into CIECIA. Based on this model, three assessment principles of the global cooperating abatement scheme are proposed, including effectiveness, feasibility, and fairness. This study simulated and analyzed six types of primary global cooperating abatement schemes. The simulated results indicate that all of the selected schemes can satisfy the climate mitigation targets by 2100. Thus, they are all effective schemes. However, the schemes have quite different feasibilities and fairness. The Stern Scheme benefits the developed countries, but is unfair to the developing countries. The Nordhaus Scheme promotes the developments of the developing countries. However, it leads to negative impacts on the interests of the developed countries. The principle of convergence on accumulated carbon emissions per capita and the principle of convergence on carbon emissions per capita benefit the economic developments of the middle and low developing countries most. However, these two types of schemes cause tremendous losses to the main economic entities in the world including China. The Pareto Improvement Scheme, which was developed from the Global Economic Growth Scheme, balances the fairness and feasibility in the carbon abatement process and realizes the Pareto improvement of accumulated utilities in all the participating countries. Thus, the Pareto Improvement Scheme is the most reasonable global cooperating carbon abatement scheme.展开更多
Accurate and effective assessment of strategic alternatives of an organization directly affects the decision-making and execution of its deve1opment strategy. In evaIuation of strategic alternatives , relevant element...Accurate and effective assessment of strategic alternatives of an organization directly affects the decision-making and execution of its deve1opment strategy. In evaIuation of strategic alternatives , relevant elements from both interna1 and external environments of an organization must be considered. In this paper we use strategic assessment model to evaluate strategic alternatives of an air-conditioning company. Strategic objectives and alternatives of the company are developed through analysis of the competitive environment, key competitors and internal conditions. The environment factors are classified into internal, task, and general opportunities and threats. Ana1ytical hierarchy process, subjective probabilities, entropy concept, and utility theory are used to enhance decision-maker's ability in evaluating strategic alternatives. The evatuation results show that the most effective strategic alternative for the company is to reduce types of products, concentrate its effort on producing window-type and cupboard-type air-conditioners, enlarge the production scale, and pre-empt the market. The company has made great progress by implementing this alternative. We conc1ude that SAM is an appropriate tool for eva1uating strategic alternatives.展开更多
文摘The performance of corporate social responsibility is conducive to the con- tinuous improvement of their profitability, and promotes the upgrading of corporation value. However, it is difficult to confirm, calculate and check the costs and benefits brought by the implementation of corporate social responsibility under the current ac- counting theory system, so it is difficult to estimate whether the fulfillment of corpo- rate social responsibility has any effects on the corporation value assessment. Therefore, based on corporate social responsibility, the correction mode of corpora- tion value assessment is put forward.
基金Project(2013CB036004) supported by National Basic Research Program(973)of ChinaProject(51378510) supported by National Natural Science Foundation of China
文摘Tunnel water inrush is one of the common geological disasters in the underground engineering construction.In order to effectively evaluate and control the occurrence of water inrush,the risk assessment model of tunnel water inrush was proposed based on improved attribute mathematical theory.The trigonometric functions were adopted to optimize the attribute mathematical theory,avoiding the influence of mutation points and linear variation zones in traditional linear measurement functions on the accuracy of the model.Based on comprehensive analysis of various factors,five parameters were selected as the evaluation indicators for the model,including tunnel head pressure,permeability coefficient of surrounding rock,crushing degree of surrounding rock,relative angle of joint plane and tunnel section size,under the principle of dimension rationality,independence,directness and quantification.The indicator classifications were determined.The links among measured data were analyzed in detail,and the objective weight of each indicator was determined by using similar weight method.Thereby the tunnel water inrush risk assessment model is established and applied in four target segments of two different tunnels in engineering.The evaluation results and the actual excavation data agree well,which indicates that the model is of high credibility and feasibility.
基金supported by National Science and Technology Major Project(No2009 ZX 05039-003,2009 ZX 05039-004,2011ZX05060-005)the National Natural Science Foundation of China(No 2010CB428801-1)state-owned land resources investigation(1212010430351)
文摘In this study, a risk-based management model is developed and applied to an industrial zone. The models proposed by the United States Environmental Protection Agency and Han Bing have been improved by adding a residual ratio of volatile organic compounds (VOC) after boiling and deleting the related parameters in half-life. Using this improved model, an integrated process was used to assess human health risk level in the study area. Compared with water quality analysis, the results highlight the importance of applying an integrated approach for decision making on risk levels and water protection. The results of this study demonstrated that: (1) Compared with these permissible level standards in China (GB 3838-2002) and National Primary Drinking Water Regulations of the United States, the residents' daily life had not been affected by the groundwater in this area (except for relative bad water quality of HB3-4 and HB3-6); (2) The typical detected organic contaminants of all groundwater samples were chloroform, carbon tetrachloride, trichloroethylene and tetrachloroethene, and the pollution sources were mainly industrial sources by preliminary investigations; (3) As for groundwater, the non-carcinogenic risk values of all samples do not exceed the permissible level of 1.0 and the carcinogenic risk values are relatively lower than the permissible level of 1.00E-06 to 1.00E-04; (4) Drinking water pathway of trichloroethylene and tetrachloroethylene mainly contribute to increasing the health risk of residents' in study areas; (5) In terms of non-carcinogenic risk and carcinogenic risk, the health risk order for drinking water pathway and dermal contact pathway was: drinking water pathway 〉 dermal contact pathway.
基金supported by the National Moon Exploration Program of China (No. TY3Q20110020)in part supported by the 13th Five-Year Community Technology Research Program of National Equipment Development Department of China (No.41409020301)the National Natural Science Foundation of China (50971094)
文摘With the development of EMC technology, EMC assessment has become increasingly important in EMC design. Although numerous EMC assessment models are available today, few of them can provide a tradeoff between efficiency and accuracy for the specific case of military vehicular communication systems. Face to this situation, a modified four-level assessment model is proposed in the paper. First, the development of EMC assessment technology is briefly reviewed, and the theoretical mechanism of EMI environment is introduced. Then, the architecture of the proposed model is outlined, and the assessment methods are explored. To demonstrate the application of it, an example involving a communication system in a military vehicle is presented. From the physical layer to the signal layer, a hierarchical assessment on the entire system is successfully performed based on the proposed model, and we can make a qualitative EMC assessment on the EMC performance of the system. Based on a comparison with the traditional model, we conclude that the proposed model is more accurate, more efficient and less time-consuming, which is suitable for the EMC assessment on militaryvehicular communication systems. We hope that the proposed model will serve as a useful reference for system-level EMC assessments for other systems.
基金the Marine Public Welfare Research Project of China (No. 201205012)Preferential Funding of Tianjin
文摘To the potential oil-spill risk caused by offshore pipeline more attention has been paid after the Dalian oil spill incident from oil-pipeline explosion. Since then an issue about how to prevent and control the sudden oil-spill from the offshore pipeline has been raised. In this paper, we proposed an optimized model to analyze the main causes(probability) of spill and the consequence with the fuzzy comprehensive assessment model. Considering the complicated assessment process for oil-spill, the assessment factor system involving the spill probability and consequence was established based on the operative manual and statistic leakage/damage data of offshore pipeline in order to estimate the integrated spill risk score automatically. The evaluated factors of spill probability could be grouped into five aspects: corrosion, fatigue, national damage, third party, and operational fault; the consequence evaluated factors of spill included hazard of oil and impact-controlling capability. With some modifications based on experts' opinions, each of the evaluated factors in our work was developed with a relative weight and evaluation criterion. A test example for an offshore pipeline in the Bohai waters was described to show how the model can be used for an actual case in more detail. By using the oil-spill risk assessment model, it is easy to determine the risk level associated with the ongoing activity and management level and hence to take the risk mitigation action immediately.
基金This work was supported by Natural Science Foundation of Hainan Province of China(No.117212)National Natural Science Foundation of China(Nos.61633008,61374007,61601262 and 61701487)Natural Science Foundation of Heilongjiang Province of China(No.F2017005)and China Scholarship Council.
文摘This paper addresses the problem of assessing and optimizing the acoustic positioning system for underwater target localization with range measurement.We present a new three-dimensional assessment model to evaluate the optimal geometric beacon formation whether meets user requirements.For mathematical tractability,it is assumed that the measurements of the range between the target and beacons are corrupted with white Gaussian noise with variance,which is distance-dependent.Then,the relationship between DOP parameters and positioning accuracy can be derived by adopting dilution of precision(DOP)parameters in the assessment model.In addition,the optimal geometric beacon formation yielding the best performance can be achieved via minimizing the values of geometric dilution of precision(GDOP)in the case where the target position is known and fixed.Next,in order to ensure that the estimated positioning accuracy on the region of interest satisfies the precision required by the user,geometric positioning accuracy(GPA),horizontal positioning accuracy(HPA)and vertical positioning accuracy(VPA)are utilized to assess the optimal geometric beacon formation.Simulation examples are designed to illustrate the exactness of the conclusion.Unlike other work that only uses GDOP to optimize the formation and cannot assess the performance of the specified size,this new three-dimensional assessment model can evaluate the optimal geometric beacon formation for each dimension of any point in three-dimensional space,which can provide guidance to optimize the performance of each specified dimension.
基金Supported by National Nature Science Foundation of China, No.30170828
文摘AIM: To set up a mathematic model for gastric cancer screening and to evaluate its function in mass screening for gastric cancer.METHODS: A case control study was carried on in 66patients and 198 normal people, then the risk and protective factors of gastric cancer were determined, including heavy manual work, foods such as small yellow-fin tuna, dried small shrimps, squills, crabs, mothers suffering from gastric diseases, spouse alive, use of refrigerators and hot food,etc. According to some principles and methods of probability and fuzzy mathematics, a quantitative assessment model was established as follows: first, we selected some factors significant in statistics, and calculated weight coefficient for each one by two different methods; second, population space was divided into gastric cancer fuzzy subset and non gastric cancer fuzzy subset, then a mathematic model for each subset was established, we got a mathematic expression of attribute degree (AD).RESULTS: Based on the data of 63 patients and 693 normal people, AD of each subject was calculated. Considering the sensitivity and specificity, the thresholds of AD values calculated were configured with 0.20 and 0.17, respectively.According to these thresholds, the sensitivity and specificity of the quantitative model were about 69% and 63%.Moreover, statistical test showed that the identification outcomes of these two different calculation methods were identical (P>0.05).CONCLUSION: The validity of this method is satisfactory.It is convenient, feasible, economic and can be used to determine individual and population risks of gastric cancer.
文摘Smoke is the main cause of fire death. In order to minimize the potential danger of smoke hazard, a rational VR based fire training simulator should fully consider all aspects of smoke hazard. In the simulator, the visualization of data based on FDS (Fire Dynamics Simulator) and FED fire dynamic data and volume rendering is further optimized, which can be effectively and quickly applied to virtual fire protection. In addition, a comprehensive smoke hazard assessment model based on FED and FED is established to assess the IHD value of different paths, which represents the safety of different paths, and can be used for evacuation or rescue in virtual training. Taking the case of campus fire drill as an experiment, the research shows the accuracy and effectiveness of smoke assessment based on FDS and FED model. The road force with the highest safety can be selected through the comprehensive model. So the assessment model is proved to be valuable.
文摘The characteristics of the financing model are firstly analyzed when the e-commerce enterprises participate in the supply chain finance. Internet supply chain finance models are divided into three categories with the standard of whether the Electronic commerce enterprises provide funds for small and medium enterprises instead of banks. And then we further study the financing process and the functions of the e-commerce platform with specific examples. Finally, combined with the characteristics of the supply chain finance model, we set up a small and medium enterprises credit evaluation model based on the principle of variable weight with its dynamic data. At the same time, a multi time points and multi indicators decision-making method based on the principle of variable weight is proposed and a specific example is presented. In this paper, the Multi-criteria decision-making model with the principle of variable weight has been used two times. At last, a typical case has been analyzed based on this model with a higher accuracy rate of credit risk assessment.
基金Under the auspices of National High Technology Research and Development Program of China (No. 2001AA132010)
文摘The influence derived from atmosphere transmitting of radar wave, in the application of high-resolution airborne Synthetic Aperture Radar (SAR) stereo positioning, may produce some phase errors, and eventually be introduced into positioning model. This paper described the principle of airborne SAR stereo positioning and the error sources of stereo positioning accuracy that arose from atmosphere transmitting, established a corresponding assess- ment model of atmosphere transmitting influence, and testified the model and the assessment principle taking the 1-m resolution airborne SAR images of Zigong City, Sichuan Province in China, as the test dataset. The test result has proved that the assessment model is reliable and reasonable. And, it has shown that the phase error arisen from time delay is the main error source during the atmosphere transmitting, which has much more influences on cross-track di- rection and introduces a stereo positioning error of about eight meters, but less on the along-track direction.
文摘Now, a rapidly growing concern for the environmental protection and resource utilization has stimulated many new activities in the in dustrialized world for coping with urgent environmental problems created by the steadily increasing consumption of industrial products. Increasingly stringent r egulations and widely expressed public concern for the environment highlight the importance of disposing solid waste generated from industrial and consumable pr oducts. How to efficiently recycle and tackle this problem has been a very impo rtant issue over the world. Designing products for recyclability is driven by environmental and economic goals. To obtain good recyclability, two measures can be adopted. One is better recycling strategy and technology; the other is design for recycling (DFR). The recycling strategies of products generally inclu de: reuse, service, remanufacturing, recycling of production scraps during the p roduct usage, recycle (separation first) and disposal. Recyclability assessment is a very important content in DFR. This paper first discusses the content of D FR and strategies and types related to products recyclability, and points out th at easy or difficult recyclability depends on the design phase. Then method and procedure of recyclability assessment based on ANN is explored in detail. The pr ocess consists of selection of the ANN input and output parameters, control of t he sample quality and construction and training of the neural network. At la st, the case study shows this method is simple and operative.
基金The Marine Charity Project under contract No.201005019-3the Marine Charity Project under contract Nos 201105009 and201105010-12the National Natural Science Foundation of China under contract No.41276018
文摘Dumping area capacity is mainly affected by the hydrodynamic process (tidal sediment, storm surge and wave, etc.) as well as the size and depth of dumping area. Based on three-dimensional ocean circulation model known as FVCOM (Finite Volume Coast and Ocean Model) and the stochastic dynamic statistical analysis model, taking advantage of dumping ground topography evolution and dumping quantity, the author aims to discuss the influence of hydrodynamic processes and dumping activity so as to built a new model of ocean dumping area capacity. With the data of depth and dumped amount in the dumping area, the changes of bottom topographic which caused by tidal current under the natural condition based on the FVCOM hydrodynamic and sediment module, the author strive to analyze the statistical relation of the changes for dumping amount, tidal current and bottom topographic. Through real data to fit revision coefficient values, which will be regarded as topographic changes reference value affected by wave and storm surges. Thus taking this evaluation as the long-term changes in the dumping capacity. In the premise of setting up the threshold of bottom topographic changes, the dumping area capacity is calculated. Take Yangtze Estuary No. 1 dumping area as an example, As the water depth reduces by 0.5 m annually, the dumping area capacity is about 6.7 million m3/a, the model results are in reasonable agreement with the actual amount. Then the model is validated in Luoyuan Bay dumping area, Shengsishangchuan Mountain dumping area, Dongding dumping area, Dongshan dumping area, and Wenzhou Port dumoin~ area. it is turns out the results are similar to that of the actual observations.
基金This work is supported by the National Natural Science Foundation of China(No.61572086,No.61402058)the Key Research and Development Project of Sichuan Province(No.20ZDYF2324,No.2019ZYD027,No.2018TJPT0012)+3 种基金the Innovation Team of Quantum Security Communication of Sichuan Province(No.17TD0009)the Academic and Technical Leaders Training Funding Support Projects of Sichuan Province(No.2016120080102643)the Application Foundation Project of Sichuan Province(No.2017JY0168)the Science and Technology Support Project of Sichuan Province(No.2018GZ0204,No.2016FZ0112).
文摘With the acceleration of the construction of quantum communication networks,scholars have proposed different quantum communication protocols for different application scenarios.However,few scholars pay attention to the risk assessment process before communication.In this paper,we propose a novel quantum risk assessment model based on quantum teleportation technology with two three-qubit GHZ states.Only by using Bell states measurements(BSMs)and two-qubit projective measurements(PJMs),the communicators can recovery any arbitrary two-qubit state.This protocol can transmit two-dimension risk assessment factors with better security performance.On the one hand,more sufficient evaluation factors allow the two communicating parties to more objectively evaluate the risk level of communication with the other party,and on the other hand,it also improves the qubit efficiency of the protocol.Moreover,we introduce the third party in this scheme can be semi-trusted,which must be full-trusted in our previous work.This change can reduce the dependence of the communication parties on the third-party organization and improve the privacy of communication.The security analysis shows that this scheme can resist internal and external attacks,and the quantum circuit diagrams also prove that our protocol is physically easier to implement.
基金Supported by the National Key Research and Development Program of China,No.2018YFC1313902。
文摘BACKGROUND Prediabetes risk assessment models derived from large sample sizes are scarce.AIM To establish a robust assessment model for prediabetes and to validate the model in different populations.METHODS The China National Diabetes and Metabolic Disorders Study(CNDMDS)collected information from 47325 participants aged at least 20 years across China from 2007 to 2008.The Thyroid Disorders,Iodine Status and Diabetes Epidemiological Survey(TIDE)study collected data from 66108 participants aged at least 18 years across China from 2015 to 2017.A logistic model with stepwise selection was performed to identify significant risk factors for prediabetes and was internally validated by bootstrapping in the CNDMDS.External validations were performed in diverse populations,including populations of Hispanic(Mexican American,other Hispanic)and non-Hispanic(White,Black and Asian)participants in the National Health and Nutrition Examination Survey(NHANES)in the United States and 66108 participants in the TIDE study in China.C statistics and calibration plots were adopted to evaluate the model’s discrimination and calibration performance.RESULTS A set of easily measured indicators(age,education,family history of diabetes,waist circumference,body mass index,and systolic blood pressure)were selected as significant risk factors.A risk assessment model was established for prediabetes with a C statistic of 0.6998(95%CI:0.6933 to 0.7063)and a calibration slope of 1.0002.When externally validated in the NHANES and TIDE studies,the model showed increased C statistics in Mexican American,other Hispanic,Non-Hispanic Black,Asian and Chinese populations but a slightly decreased C statistic in non-Hispanic White individuals.Applying the risk assessment model to the TIDE population,we obtained a C statistic of 0.7308(95%CI:0.7260 to 0.7357)and a calibration slope of 1.1137.A risk score was derived to assess prediabetes.Individuals with scores≥7 points were at high risk of prediabetes,with a sensitivity of 60.19%and specificity of 67.59%.CONCLUSION An easy-to-use assessment model for prediabetes was established and was internally and externally validated in different populations.The model had a satisfactory performance and could screen individuals with a high risk of prediabetes.
基金supported by the projects of the China Geological Survey(DD20221729,DD20190291)Zhuhai Urban Geological Survey(including informatization)(MZCD–2201–008).
文摘Machine learning is currently one of the research hotspots in the field of landslide prediction.To clarify and evaluate the differences in characteristics and prediction effects of different machine learning models,Conghua District,which is the most prone to landslide disasters in Guangzhou,was selected for landslide susceptibility evaluation.The evaluation factors were selected by using correlation analysis and variance expansion factor method.Applying four machine learning methods namely Logistic Regression(LR),Random Forest(RF),Support Vector Machines(SVM),and Extreme Gradient Boosting(XGB),landslide models were constructed.Comparative analysis and evaluation of the model were conducted through statistical indices and receiver operating characteristic(ROC)curves.The results showed that LR,RF,SVM,and XGB models have good predictive performance for landslide susceptibility,with the area under curve(AUC)values of 0.752,0.965,0.996,and 0.998,respectively.XGB model had the highest predictive ability,followed by RF model,SVM model,and LR model.The frequency ratio(FR)accuracy of LR,RF,SVM,and XGB models was 0.775,0.842,0.759,and 0.822,respectively.RF and XGB models were superior to LR and SVM models,indicating that the integrated algorithm has better predictive ability than a single classification algorithm in regional landslide classification problems.
基金2024 Key Project of Teaching Reform Research and Practice in Higher Education in Henan Province“Exploration and Practice of Training Model for Outstanding Students in Basic Mechanics Discipline”(2024SJGLX094)Henan Province“Mechanics+X”Basic Discipline Outstanding Student Training Base2024 Research and Practice Project of Higher Education Teaching Reform in Henan University of Science and Technology“Optimization and Practice of Ability-Oriented Teaching Mode for Computational Mechanics Course:A New Exploration in Cultivating Practical Simulation Engineers”(2024BK074)。
文摘This paper takes the assessment and evaluation of computational mechanics course as the background,and constructs a diversified course evaluation system that is student-centered and integrates both quantitative and qualitative evaluation methods.The system not only pays attention to students’practical operation and theoretical knowledge mastery but also puts special emphasis on the cultivation of students’innovative abilities.In order to realize a comprehensive and objective evaluation,the assessment and evaluation method of the entropy weight model combining TOPSIS(Technique for Order Preference by Similarity to Ideal Solution)multi-attribute decision analysis and entropy weight theory is adopted,and its validity and practicability are verified through example analysis.This method can not only comprehensively and objectively evaluate students’learning outcomes,but also provide a scientific decision-making basis for curriculum teaching reform.The implementation of this diversified course evaluation system can better reflect the comprehensive ability of students and promote the continuous improvement of teaching quality.
基金Key Discipline Project of Shanghai Municipal Education Commission(No.J50402)Key Research of Shanghai Institute of Tourism(No.RS2015-B3)
文摘Recent years have witnessed a rapid development of star-rated hotels in China, especially high- end star-rated hotels. Consequently, there are now approximately12 000 hotels in China. One bottleneck within the industry is its huge energy consumption and carbon emissions, but the development of a comprehensive energy consumption assessment has lagged. Here, a comprehensive energy consumption and carbon emission model suitable for hospitality is established, using comprehensive data collected for hotels over six years and with reference to general international methods, decomposition analysis methods as recommended by the IPCC, and related standards in China. Our study shows that the maximum comparable unit energy consumption per building area among four- and five-star hotels is 73.26 kg ce m-2 y-l. Through energy-saving reconstruction, the comprehensive energy consumption of five-star hotels has declined by 4.1% in six years and is smaller than the advanced comparable value of 55 kg ce m2 y4. The comparable unit energy consumption per area building of most two- and three-star hotels (53 kg ce m2 y-l) is higher than the reasonable value. There are large numbers of hotels of this type in China and the potential energy savings are huge. Analyzing factors of energy consumption, we found that indirect carbon emissions from electricity usage are the most significant. From an energy consumption structural perspective, Heating, Ventilation and Air Conditioning (HVAC) System accounts for most energy consumption. This research provides a foundation for further examination of energy-savings, emission reduction plans and Monitoring Reporting Verification (MRV) in the hospitality sector.
基金the National Basic Research Program of China (Grant No. 2012CB955800)
文摘From the perspective of global economic general equilibrium, this study developed a new climate change IAM named CIECIA. The economic core of this IAM is a multi-country-sector general equilibrium model. The endogenous technology progress mode is introduced into CIECIA. Based on this model, three assessment principles of the global cooperating abatement scheme are proposed, including effectiveness, feasibility, and fairness. This study simulated and analyzed six types of primary global cooperating abatement schemes. The simulated results indicate that all of the selected schemes can satisfy the climate mitigation targets by 2100. Thus, they are all effective schemes. However, the schemes have quite different feasibilities and fairness. The Stern Scheme benefits the developed countries, but is unfair to the developing countries. The Nordhaus Scheme promotes the developments of the developing countries. However, it leads to negative impacts on the interests of the developed countries. The principle of convergence on accumulated carbon emissions per capita and the principle of convergence on carbon emissions per capita benefit the economic developments of the middle and low developing countries most. However, these two types of schemes cause tremendous losses to the main economic entities in the world including China. The Pareto Improvement Scheme, which was developed from the Global Economic Growth Scheme, balances the fairness and feasibility in the carbon abatement process and realizes the Pareto improvement of accumulated utilities in all the participating countries. Thus, the Pareto Improvement Scheme is the most reasonable global cooperating carbon abatement scheme.
文摘Accurate and effective assessment of strategic alternatives of an organization directly affects the decision-making and execution of its deve1opment strategy. In evaIuation of strategic alternatives , relevant elements from both interna1 and external environments of an organization must be considered. In this paper we use strategic assessment model to evaluate strategic alternatives of an air-conditioning company. Strategic objectives and alternatives of the company are developed through analysis of the competitive environment, key competitors and internal conditions. The environment factors are classified into internal, task, and general opportunities and threats. Ana1ytical hierarchy process, subjective probabilities, entropy concept, and utility theory are used to enhance decision-maker's ability in evaluating strategic alternatives. The evatuation results show that the most effective strategic alternative for the company is to reduce types of products, concentrate its effort on producing window-type and cupboard-type air-conditioners, enlarge the production scale, and pre-empt the market. The company has made great progress by implementing this alternative. We conc1ude that SAM is an appropriate tool for eva1uating strategic alternatives.