Teacher-student collaborative assessment(TSCA)aims to address the challenges of responding to students’work in the Production-Oriented Approach:low efficiency and poor effectiveness.As part of a bigger project carrie...Teacher-student collaborative assessment(TSCA)aims to address the challenges of responding to students’work in the Production-Oriented Approach:low efficiency and poor effectiveness.As part of a bigger project carried out in a Chinese university over a period of three years,the present study explored how the teacher prepared and implemented TSCA in class,especially with a focus on how she determined the assessing objective and worked collaboratively with her students in class to achieve it,using the students’written and translated texts as examples.By adopting the dialectical research(DR)method,this paper collected qualitative data such as teaching plans,classroom recordings,and reflective journals of the teacher-researcher(the author),along with students’written drafts and translated texts.TSCA theory and classroom practice have been refined simultaneously by means of putting theory into practice and reflecting upon it.The optimized pre-class and in-class procedures may shed some light on applying TSCA to L2 classrooms.展开更多
Accidents and injuries related to work are major occupational health problems in most of the industrialized countries.Traditional approaches to manage workplace safety in mines have mainly focused on job redesign and ...Accidents and injuries related to work are major occupational health problems in most of the industrialized countries.Traditional approaches to manage workplace safety in mines have mainly focused on job redesign and technical aspects of engineering systems.It is being realized that compliance to rules and regulations of mines is a prerequisite;however,it is not sufficient to achieve further reduction in accident and injury rates in mines.Proactive approaches are necessary to further improve the safety standards in mines.Unsafe conditions and practices in mines lead to a number of accidents,which in turn may cause loss and injury to human lives,damages to property,and loss of production.Hazard identification and risk assessment is an important task for the mining industry which needs to consider all the risk factors at workplaces.Applications of risk management approaches in mines are necessary to identify and quantify potential hazards and to suggest effective solutions.In this paper,the following risk estimation techniques were discussed:(i)DGMS(Directorate General of Mines Safety,India)risk rating criterion,and(ii)a matrix based approach.The proposed tools were demonstrated through an application in an opencast coal mine in India.It was inferred that the risk assessment approach can be used as an effective tool to indentify and control hazards in mines.展开更多
The damage effect assessment of anti-ship missiles combines system science and weapon science,which can provide reference for the assessment of battlefield damage situation.In order to solve the difficulty of heteroge...The damage effect assessment of anti-ship missiles combines system science and weapon science,which can provide reference for the assessment of battlefield damage situation.In order to solve the difficulty of heterogeneous data aggregation and the difficulty in constructing the mapping between factors and damage effect,this paper analyzes the specific damage process of the anti-ship missile to the ship,and proposes a synthetic Evidential Reasoning(ER)–Adaptive Neural Fuzzy Inference System(ANFIS)to assess the damage effect.To solve the problem of fuzziness and uncertainty of criteria in the assessment process,the belief structure model is used to transform qualitative and quantitative information into a unified mathematical structure,and ER algorithm is used to fuse the information of lower-level criteria.In order to solve the problem of fuzziness and uncertainty of the information contained in the first-level variables,and the strong non-linear characteristics of the mapping between first-level variables and damage effect,the ANFIS with selfadaptation and self-learning is constructed.The map between the three first-level variables and damage effect is established,and the interaction process of the various factors in the damage effect assessment are clear.Sensitivity analysis shows that assessment model has good stability.The result analysis and comparative analysis show that the process proposed in this paper can effectively assess the damage effect of anti-ship missiles,and all criteria data are objective and comparable.展开更多
Security assessment can help understand the security conditions of an information system and yield results highly conducive to the solution of security problems in it. Taking the computer networks in a certain univers...Security assessment can help understand the security conditions of an information system and yield results highly conducive to the solution of security problems in it. Taking the computer networks in a certain university as samples, this paper, with the information system security assessment model as its foundation, proposes a multi-attribute group decision-making （MAGDM） security assessment method based on a variable consistency dominance-based rough set approach （VC-DRSA）. This assessment method combines VC-DRSA with the analytic hierarchy process （AHP）, uncovers the inherent information hidden in data via the quality of sorting （QoS）, and makes a synthetic security assessment of the information system after determining the security attribute weight. The sample findings show that this method can effectively remove the bottleneck of MAGDM, thus assuming practical significance in information system security assessment.展开更多
The past two decades have seen formative assessment claim legitimacy in policy discourse and engender immense tensions within the testing-dominated assessment regimes of multiple educational settings.These tensions,al...The past two decades have seen formative assessment claim legitimacy in policy discourse and engender immense tensions within the testing-dominated assessment regimes of multiple educational settings.These tensions,along with the top-down approach of the policy process,have made the inroads of formative assessment in local contexts very complex.This study seeks to unveil the localized appropriation and actualization of a formative assessment initiative in the College English area at a Chinese local university.The focus is on how the key actors at the institutional and classroom levels appropriate and negotiate the policy meaning within their local community of practice.Analysis of an individual interview with the dean and a focus-group interview with six 1 teachers has revealed a“two-hand”approach to the national policy and a nested mediation from local constraints,“cultural tools for thinking”and,more importantly,power in the policymaking process at the institutional level.The classroom level,on the other hand,witnesses capable teachers exercising their agency within a limited space.As a result,we would caution that power and agency could be solid mediators in the policy process and need to be exercised with care to ensure a more coherent implementation of assessment innovations.展开更多
Casing deformation is a widespread problem in a certain block of Jiaoshiba Shale Gas Field in Sichuan Basin,China,and it severely limits the development benefits of shale gas in that block.Based on the spatiotemporal ...Casing deformation is a widespread problem in a certain block of Jiaoshiba Shale Gas Field in Sichuan Basin,China,and it severely limits the development benefits of shale gas in that block.Based on the spatiotemporal characteristics of block formation,fracture development,and casing deformation occurrence,this paper employs an integrated geological—engineering research approach to identify the primary mechanisms governing casing deformation within the block and proposes countermeasures to prevent such deformation.The present research indicates the following findings:(1)The block has undergone multiple phases of tectonic superposition,with fracture development serving as the geological factor causing casing deformation.(2)Fracturing activation constitutes the engineering factor causing casing deformation,with 4 mm of formation slip inducing deformation.(3)The fracture activation risk map shows that Class Ⅰ and Class Ⅱ fractures account for 73.36%of the total recorded in the block.Within the most susceptible Class I risk zone,the critical activation pressure increment for fracturing operations ranges from 13.43 MPa to 13.99 MPa.Based on the distribution of casing failure risk zones identified in the fracture activation risk map,this paper proposes relevant technical countermeasures for preventing casing failure from three perspectives:shale gas well location deployment,drilling techniques,and fracturing techniques.These measures provide robust support for safeguarding the integrity of casing systems within the studied block.展开更多
Environmentalists'approach to sustainable development is essentially different fromeconomists'in that environmental sustainability is set as a condition in biophysical limits. Furthermorethere exist alternativ...Environmentalists'approach to sustainable development is essentially different fromeconomists'in that environmental sustainability is set as a condition in biophysical limits. Furthermorethere exist alternative strategies for achieving environmental sustainability. This paper intends to assessand compare these alternatives in the context of environmental resource stock and economic outcomes , sothat the circumstances in which a particular strategy is preferred.would be suggested.展开更多
The present study aims to describe theme choices in students＇ writing with a systemic functional approach. The analysis of a student＇s written work chosen at random shows the student writer can apply various theme t...The present study aims to describe theme choices in students＇ writing with a systemic functional approach. The analysis of a student＇s written work chosen at random shows the student writer can apply various theme types in writing after receiving instruction in reading class. The author hopes to propose the pedagogical implication of teaching functional linguistics knowledge to advanced learners, because it gives the view to the students to write cohesive and coherent texts.展开更多
Epidemiological studies support the idea that most human cancers are related to chemicals present in the human environment. In turn, chemicals are believed to cause cancer via either genotoxic or non-genotoxic mechani...Epidemiological studies support the idea that most human cancers are related to chemicals present in the human environment. In turn, chemicals are believed to cause cancer via either genotoxic or non-genotoxic mechanisms. There were described in literature several simple, rapid and inexpensive short term tests to reasonably predict the genotoxic nature of chemicals but in contrast, there is no reliable test or battery of tests available to predict the carcinogenicity of non-genotoxic compounds and this poses a major problem to their risk assessment. In addition, there are conflictive opinions about risk assessment needs for both classes of carcinogens. Some workers believe that for non-genotoxic carcinogens, thresholds for exposure can be drawn while others do not. In this review, the reasons behind both of these opinions and the present hypotheses about the mechanism of action of non-genotoxic carcinogens are described and analyzed in relation to future needs.展开更多
The site of Mansehra is located seismically in an active regime, known as the Crystalline Nappe Zone and Hazara-Kashmir Syntaxis in NW Himalayas, Pakistan. Seismic Hazard Assessment （SHA） for the site has been carri...The site of Mansehra is located seismically in an active regime, known as the Crystalline Nappe Zone and Hazara-Kashmir Syntaxis in NW Himalayas, Pakistan. Seismic Hazard Assessment （SHA） for the site has been carried out by considering the earthquake source zones, selection of appropriate attenuation equations, near fault effects and maximum potential magnitude estimation. The Mansehra Thrust, Oghi Fault, Banna Thrust, Balakot Shear Zone, Main Boundary Thrust, Panjal Thrust, Jhelum Fault and Muzaffarabad Fault and, further to the south, the Sanghargali, Nathiagali, and Thandiani Thrusts are the most critical tectonic features within the 50 km radius of Mansehra. Using the available instrumental seismological data from 1904 to 2007, SHA has been carried out. Other reactivated critical tectonic features in the area have been investigated. Among them the Balakot-Bagh fault, with the fault length of 120 km from Balakot to Poonch, has been considered as the most critical tectonic feature on the basis of geological/structural/seismological data. The potential earthquake of maximum magnitude 7.8 has been assigned to the Balakot-Bagh fault using four regression relations. The peak ground acceleration value of 0.25 g （10% probability of exceedance for 50 years） and 0.5 g has been calculated with the help of the attenuation equation using probabilistic and deterministic approaches.展开更多
In order to understand the security conditions of the incomplete interval-valued information system （IllS） and acquire the corresponding solution of security problems, this paper proposes a multi-attribute group dec...In order to understand the security conditions of the incomplete interval-valued information system （IllS） and acquire the corresponding solution of security problems, this paper proposes a multi-attribute group decision- making （MAGDM） security assessment method based on the technique for order performance by similarity to ideal solution （TOPSIS）. For IllS with preference information, combining with dominance-based rough set approach （DRSA）, the effect of incomplete interval-valued information on decision results is discussed. For the imprecise judgment matrices, the security attribute weight can be obtained using Gibbs sampling. A numerical example shows that the proposed method can acquire some valuable knowledge hidden in the incomplete interval-valued information. The effectiveness of the proposed method in the synthetic security assessment for IIIS is verified.展开更多
Anchovy(Engraulis japonicus) is an abundant fish species in the Yellow Sea,and its natural stock is decreasing rapidly in recent years. Based on the stock-recruitment(SR) data from 1987 to 2002 published in Zhao et al...Anchovy(Engraulis japonicus) is an abundant fish species in the Yellow Sea,and its natural stock is decreasing rapidly in recent years. Based on the stock-recruitment(SR) data from 1987 to 2002 published in Zhao et al.(2003),the criterion BIC(Bayesian Information Criterion) is applied to selecting a suitable model from six normal and lognormal error structured SR statisti-cal models,the age-structured model is used to calculate the biological reference points(BRPs),and the precision of the SR parame-ters and BRPs are calculated using bootstrap method. The results indicate that the anchovy fishery resource in the Yellow Sea is in an over-fished state. The precaution management principle requires that the fishery should be closed immediately.展开更多
Faced with the problem of how to evaluate students' learning properly,many teachers begin to search for alternative assessments.Interest is growing in meaningful assessment and the use of portfolio assessment has ...Faced with the problem of how to evaluate students' learning properly,many teachers begin to search for alternative assessments.Interest is growing in meaningful assessment and the use of portfolio assessment has become a good choice to improve both teaching and learning.In the article,the major principles and the approaches of portfolio assessment are explained.By analysing the benefits and limitations of portfolio assessment,the article concludes that despite the issues,portfolio assessment can contribute to the enhancement of students' learning and the improvement of teaching.展开更多
Turbine blisks are assembled using blades,disks and casings.They can endure complex loads at a high temperature,high pressure and high speed.The safe operation of assembled structures depends on the reliability of eac...Turbine blisks are assembled using blades,disks and casings.They can endure complex loads at a high temperature,high pressure and high speed.The safe operation of assembled structures depends on the reliability of each component.Monte Carlo(MC)simulation is commonly used to analyze structural reliability,but this method needs to run thousands of computations.In order to assess the clearance reliability of assembled structures in an efficient and precise manner,the novel Kriging-based decomposed-coordinated(DC)(DCNK)approach is proposed by integrating the DC strategy,the Kriging model and the importance sampling-based Markov chain(MCIS)technique.In this method,the DC strategy is used to decompose a multi-objective problem into many single-objective problems.The relationships between these many single-objectives and the overall objective are then coordinated.The Kriging model is applied to establish the limit state functions of the single-objectives and multi-objective problems,while the MCIS method is used to assess the structural assembled clearance reliability.Moreover,a highly nonlinear complex compound function is first utilized to verify the DCNK model from a mathematical perspective.Then,the reliability of an aeroengine high-pressure turbine(HPT)blade-tip radial running clearance(BTRRC)is analyzed to validate the DCNK approach by considering thermo-structural interaction.The analytical results show that the reliability is 0.9976 when the allowance value of the BTTRC is 1.7650×10^(−3)m.Compared with different methodologies(including direct simulation,the classical Kriging model,and the weighted response surface method(WRSM)),the proposed method holds obvious advantages in computing time and precision,as well as simulation efficiency and precision.The efforts of this paper provide a useful approach to analyzing assembled clearance reliability and contribute to the development of structural reliability theory.展开更多
This paper proposes a modeling system developed in order to analyze the urban freight transport and logistics within urban and metropolitan areas. A review of models developed to simulate this segment of mobility is a...This paper proposes a modeling system developed in order to analyze the urban freight transport and logistics within urban and metropolitan areas. A review of models developed to simulate this segment of mobility is also reported. The review analysis highlights the limits of models for the ex-ante assessment of city logistics measures. For this reason this paper proposes a new modeling system approach for the assessment of city logistics measures. It is made of different steps approaching problems related to quantity OD （Origin-Destination） flows, restocking type OD flows, delivery OD flows, delivery OD flows for time slice and vehicle type, and vehicle OD flows. This modeling system has been specified and calibrated using some surveys carried out in the inner area of Rome where more than 500 truck drivers and more than 600 retailers have been interviewed.展开更多
One of the most devastating effects of earthquakes in the seismic regions is liquefaction. Many research works have been done in this field and at present different methods are available for the liquefaction potential...One of the most devastating effects of earthquakes in the seismic regions is liquefaction. Many research works have been done in this field and at present different methods are available for the liquefaction potential assessment. The liquefaction is a very significant phenomenon in clayey silty soils, silty sands and also sands. The high potential of liquefaction is generally recognized when these type of soils are laid under the hydrostatic water table. This paper make an overview of two different methods for the evaluation of liquefaction potential, and a case study is presented. Two methods presented here are the Deterministic Approach proposed by Robertson and Wride (1998), and the Probabilistic Approach proposed by Moss and co-workers. Case study of the liquefaction potential evaluation is done for the Golem area, where geotechnical data from CPTU test were collected. The results of analysis in the Golem area show that liquefaction has medium susceptibly to occur. From the analyses, it is shown that the Probabilistic Approach gives more accurate information about the risk of liquefaction than the Deterministic Approach.展开更多
Due to rapidly development of information systems, risk and security issues have increased and became a phenomenon that concerns every organization, without considering the size of it. To achieve desired results, mana...Due to rapidly development of information systems, risk and security issues have increased and became a phenomenon that concerns every organization, without considering the size of it. To achieve desired results, managers have to implement methods of evaluating and mitigating risk as part of a process well elaborated. Security risk management helps managers to better control the business practices and improve the business process. An effective risk management process is based on a successful IT security program. This doesn＇t mean that the main goal of an organization＇s risk management process is to protect its IT assets, but to protect the organization and its ability to perform their missions. During this process, managers have to take into consideration risks that can affect the organization and apply the most suitable measures to minimize their impact. The most important task is choosing the best suited method for analyzing the existing risk properly. Several methods have been developed, being classified in quantitative and qualitative approaches of evaluating risk. The purpose of this paper is to present the advantages and disadvantages of each approach taking current needs and opportunities into consideration.展开更多
The paper proposes a matrix-based approach that a designer can use to evaluate the sustainability of one or more design solutions in the conceptual phase of a product development process. The methodology is structured...The paper proposes a matrix-based approach that a designer can use to evaluate the sustainability of one or more design solutions in the conceptual phase of a product development process. The methodology is structured in two main phases. In the first one, a data structure, called Augmented-DSM （Design Structure Matrix）, has to be drawn in order to collect design information such as functional links among product components, indicators that provide information about the life cycle of each element, connections with the environment and toward other systems. The matrix is based on a DSM format, where new records were introduced to store and organize different types of data and an editing protocol was formalized. In the second stage, a set of procedures have to be applied in order to evaluate sustainability of a design solution and compare it with the others. The presented procedures, in fact, allow designers to assess a product in its proper characteristics, evaluate a device during its use stage and verify the coherence of links present in the functional model. This new approach is conceived to manage different performance indicators and, as a support tool, it is an attempt to aid designers in a quantitative evaluation.展开更多
文摘Teacher-student collaborative assessment(TSCA)aims to address the challenges of responding to students’work in the Production-Oriented Approach:low efficiency and poor effectiveness.As part of a bigger project carried out in a Chinese university over a period of three years,the present study explored how the teacher prepared and implemented TSCA in class,especially with a focus on how she determined the assessing objective and worked collaboratively with her students in class to achieve it,using the students’written and translated texts as examples.By adopting the dialectical research(DR)method,this paper collected qualitative data such as teaching plans,classroom recordings,and reflective journals of the teacher-researcher(the author),along with students’written drafts and translated texts.TSCA theory and classroom practice have been refined simultaneously by means of putting theory into practice and reflecting upon it.The optimized pre-class and in-class procedures may shed some light on applying TSCA to L2 classrooms.
文摘Accidents and injuries related to work are major occupational health problems in most of the industrialized countries.Traditional approaches to manage workplace safety in mines have mainly focused on job redesign and technical aspects of engineering systems.It is being realized that compliance to rules and regulations of mines is a prerequisite;however,it is not sufficient to achieve further reduction in accident and injury rates in mines.Proactive approaches are necessary to further improve the safety standards in mines.Unsafe conditions and practices in mines lead to a number of accidents,which in turn may cause loss and injury to human lives,damages to property,and loss of production.Hazard identification and risk assessment is an important task for the mining industry which needs to consider all the risk factors at workplaces.Applications of risk management approaches in mines are necessary to identify and quantify potential hazards and to suggest effective solutions.In this paper,the following risk estimation techniques were discussed:(i)DGMS(Directorate General of Mines Safety,India)risk rating criterion,and(ii)a matrix based approach.The proposed tools were demonstrated through an application in an opencast coal mine in India.It was inferred that the risk assessment approach can be used as an effective tool to indentify and control hazards in mines.
文摘The damage effect assessment of anti-ship missiles combines system science and weapon science,which can provide reference for the assessment of battlefield damage situation.In order to solve the difficulty of heterogeneous data aggregation and the difficulty in constructing the mapping between factors and damage effect,this paper analyzes the specific damage process of the anti-ship missile to the ship,and proposes a synthetic Evidential Reasoning(ER)–Adaptive Neural Fuzzy Inference System(ANFIS)to assess the damage effect.To solve the problem of fuzziness and uncertainty of criteria in the assessment process,the belief structure model is used to transform qualitative and quantitative information into a unified mathematical structure,and ER algorithm is used to fuse the information of lower-level criteria.In order to solve the problem of fuzziness and uncertainty of the information contained in the first-level variables,and the strong non-linear characteristics of the mapping between first-level variables and damage effect,the ANFIS with selfadaptation and self-learning is constructed.The map between the three first-level variables and damage effect is established,and the interaction process of the various factors in the damage effect assessment are clear.Sensitivity analysis shows that assessment model has good stability.The result analysis and comparative analysis show that the process proposed in this paper can effectively assess the damage effect of anti-ship missiles,and all criteria data are objective and comparable.
基金Supported by the High Technology Research and Development Programme of China (No. 2007AA01Z473)
文摘Security assessment can help understand the security conditions of an information system and yield results highly conducive to the solution of security problems in it. Taking the computer networks in a certain university as samples, this paper, with the information system security assessment model as its foundation, proposes a multi-attribute group decision-making （MAGDM） security assessment method based on a variable consistency dominance-based rough set approach （VC-DRSA）. This assessment method combines VC-DRSA with the analytic hierarchy process （AHP）, uncovers the inherent information hidden in data via the quality of sorting （QoS）, and makes a synthetic security assessment of the information system after determining the security attribute weight. The sample findings show that this method can effectively remove the bottleneck of MAGDM, thus assuming practical significance in information system security assessment.
基金based on research projects sponsored by the National Social Science Fund of China(NSSFC)(No.17BYY100)the China Association of Higher Education—Foreign Language Teaching and Research Association[21WYJYYB24]。
文摘The past two decades have seen formative assessment claim legitimacy in policy discourse and engender immense tensions within the testing-dominated assessment regimes of multiple educational settings.These tensions,along with the top-down approach of the policy process,have made the inroads of formative assessment in local contexts very complex.This study seeks to unveil the localized appropriation and actualization of a formative assessment initiative in the College English area at a Chinese local university.The focus is on how the key actors at the institutional and classroom levels appropriate and negotiate the policy meaning within their local community of practice.Analysis of an individual interview with the dean and a focus-group interview with six 1 teachers has revealed a“two-hand”approach to the national policy and a nested mediation from local constraints,“cultural tools for thinking”and,more importantly,power in the policymaking process at the institutional level.The classroom level,on the other hand,witnesses capable teachers exercising their agency within a limited space.As a result,we would caution that power and agency could be solid mediators in the policy process and need to be exercised with care to ensure a more coherent implementation of assessment innovations.
文摘Casing deformation is a widespread problem in a certain block of Jiaoshiba Shale Gas Field in Sichuan Basin,China,and it severely limits the development benefits of shale gas in that block.Based on the spatiotemporal characteristics of block formation,fracture development,and casing deformation occurrence,this paper employs an integrated geological—engineering research approach to identify the primary mechanisms governing casing deformation within the block and proposes countermeasures to prevent such deformation.The present research indicates the following findings:(1)The block has undergone multiple phases of tectonic superposition,with fracture development serving as the geological factor causing casing deformation.(2)Fracturing activation constitutes the engineering factor causing casing deformation,with 4 mm of formation slip inducing deformation.(3)The fracture activation risk map shows that Class Ⅰ and Class Ⅱ fractures account for 73.36%of the total recorded in the block.Within the most susceptible Class I risk zone,the critical activation pressure increment for fracturing operations ranges from 13.43 MPa to 13.99 MPa.Based on the distribution of casing failure risk zones identified in the fracture activation risk map,this paper proposes relevant technical countermeasures for preventing casing failure from three perspectives:shale gas well location deployment,drilling techniques,and fracturing techniques.These measures provide robust support for safeguarding the integrity of casing systems within the studied block.
文摘Environmentalists'approach to sustainable development is essentially different fromeconomists'in that environmental sustainability is set as a condition in biophysical limits. Furthermorethere exist alternative strategies for achieving environmental sustainability. This paper intends to assessand compare these alternatives in the context of environmental resource stock and economic outcomes , sothat the circumstances in which a particular strategy is preferred.would be suggested.
文摘The present study aims to describe theme choices in students＇ writing with a systemic functional approach. The analysis of a student＇s written work chosen at random shows the student writer can apply various theme types in writing after receiving instruction in reading class. The author hopes to propose the pedagogical implication of teaching functional linguistics knowledge to advanced learners, because it gives the view to the students to write cohesive and coherent texts.
文摘Epidemiological studies support the idea that most human cancers are related to chemicals present in the human environment. In turn, chemicals are believed to cause cancer via either genotoxic or non-genotoxic mechanisms. There were described in literature several simple, rapid and inexpensive short term tests to reasonably predict the genotoxic nature of chemicals but in contrast, there is no reliable test or battery of tests available to predict the carcinogenicity of non-genotoxic compounds and this poses a major problem to their risk assessment. In addition, there are conflictive opinions about risk assessment needs for both classes of carcinogens. Some workers believe that for non-genotoxic carcinogens, thresholds for exposure can be drawn while others do not. In this review, the reasons behind both of these opinions and the present hypotheses about the mechanism of action of non-genotoxic carcinogens are described and analyzed in relation to future needs.
文摘The site of Mansehra is located seismically in an active regime, known as the Crystalline Nappe Zone and Hazara-Kashmir Syntaxis in NW Himalayas, Pakistan. Seismic Hazard Assessment （SHA） for the site has been carried out by considering the earthquake source zones, selection of appropriate attenuation equations, near fault effects and maximum potential magnitude estimation. The Mansehra Thrust, Oghi Fault, Banna Thrust, Balakot Shear Zone, Main Boundary Thrust, Panjal Thrust, Jhelum Fault and Muzaffarabad Fault and, further to the south, the Sanghargali, Nathiagali, and Thandiani Thrusts are the most critical tectonic features within the 50 km radius of Mansehra. Using the available instrumental seismological data from 1904 to 2007, SHA has been carried out. Other reactivated critical tectonic features in the area have been investigated. Among them the Balakot-Bagh fault, with the fault length of 120 km from Balakot to Poonch, has been considered as the most critical tectonic feature on the basis of geological/structural/seismological data. The potential earthquake of maximum magnitude 7.8 has been assigned to the Balakot-Bagh fault using four regression relations. The peak ground acceleration value of 0.25 g （10% probability of exceedance for 50 years） and 0.5 g has been calculated with the help of the attenuation equation using probabilistic and deterministic approaches.
基金Supported by the National Natural Science Foundation of China（No.60605019）
文摘In order to understand the security conditions of the incomplete interval-valued information system （IllS） and acquire the corresponding solution of security problems, this paper proposes a multi-attribute group decision- making （MAGDM） security assessment method based on the technique for order performance by similarity to ideal solution （TOPSIS）. For IllS with preference information, combining with dominance-based rough set approach （DRSA）, the effect of incomplete interval-valued information on decision results is discussed. For the imprecise judgment matrices, the security attribute weight can be obtained using Gibbs sampling. A numerical example shows that the proposed method can acquire some valuable knowledge hidden in the incomplete interval-valued information. The effectiveness of the proposed method in the synthetic security assessment for IIIS is verified.
基金This work is supported by the National Basic Research Program of China(No.2005CB422306,973 program)National Natural Science Foundation of China(30271025).
文摘Anchovy(Engraulis japonicus) is an abundant fish species in the Yellow Sea,and its natural stock is decreasing rapidly in recent years. Based on the stock-recruitment(SR) data from 1987 to 2002 published in Zhao et al.(2003),the criterion BIC(Bayesian Information Criterion) is applied to selecting a suitable model from six normal and lognormal error structured SR statisti-cal models,the age-structured model is used to calculate the biological reference points(BRPs),and the precision of the SR parame-ters and BRPs are calculated using bootstrap method. The results indicate that the anchovy fishery resource in the Yellow Sea is in an over-fished state. The precaution management principle requires that the fishery should be closed immediately.
文摘Faced with the problem of how to evaluate students' learning properly,many teachers begin to search for alternative assessments.Interest is growing in meaningful assessment and the use of portfolio assessment has become a good choice to improve both teaching and learning.In the article,the major principles and the approaches of portfolio assessment are explained.By analysing the benefits and limitations of portfolio assessment,the article concludes that despite the issues,portfolio assessment can contribute to the enhancement of students' learning and the improvement of teaching.
基金This paper is supported by the National Natural Science Foundation of China(51875465)the Civil Aircraft Scientific Research Project.The authors would like to thank their generous supports.
文摘Turbine blisks are assembled using blades,disks and casings.They can endure complex loads at a high temperature,high pressure and high speed.The safe operation of assembled structures depends on the reliability of each component.Monte Carlo(MC)simulation is commonly used to analyze structural reliability,but this method needs to run thousands of computations.In order to assess the clearance reliability of assembled structures in an efficient and precise manner,the novel Kriging-based decomposed-coordinated(DC)(DCNK)approach is proposed by integrating the DC strategy,the Kriging model and the importance sampling-based Markov chain(MCIS)technique.In this method,the DC strategy is used to decompose a multi-objective problem into many single-objective problems.The relationships between these many single-objectives and the overall objective are then coordinated.The Kriging model is applied to establish the limit state functions of the single-objectives and multi-objective problems,while the MCIS method is used to assess the structural assembled clearance reliability.Moreover,a highly nonlinear complex compound function is first utilized to verify the DCNK model from a mathematical perspective.Then,the reliability of an aeroengine high-pressure turbine(HPT)blade-tip radial running clearance(BTRRC)is analyzed to validate the DCNK approach by considering thermo-structural interaction.The analytical results show that the reliability is 0.9976 when the allowance value of the BTTRC is 1.7650×10^(−3)m.Compared with different methodologies(including direct simulation,the classical Kriging model,and the weighted response surface method(WRSM)),the proposed method holds obvious advantages in computing time and precision,as well as simulation efficiency and precision.The efforts of this paper provide a useful approach to analyzing assembled clearance reliability and contribute to the development of structural reliability theory.
文摘This paper proposes a modeling system developed in order to analyze the urban freight transport and logistics within urban and metropolitan areas. A review of models developed to simulate this segment of mobility is also reported. The review analysis highlights the limits of models for the ex-ante assessment of city logistics measures. For this reason this paper proposes a new modeling system approach for the assessment of city logistics measures. It is made of different steps approaching problems related to quantity OD （Origin-Destination） flows, restocking type OD flows, delivery OD flows, delivery OD flows for time slice and vehicle type, and vehicle OD flows. This modeling system has been specified and calibrated using some surveys carried out in the inner area of Rome where more than 500 truck drivers and more than 600 retailers have been interviewed.
文摘One of the most devastating effects of earthquakes in the seismic regions is liquefaction. Many research works have been done in this field and at present different methods are available for the liquefaction potential assessment. The liquefaction is a very significant phenomenon in clayey silty soils, silty sands and also sands. The high potential of liquefaction is generally recognized when these type of soils are laid under the hydrostatic water table. This paper make an overview of two different methods for the evaluation of liquefaction potential, and a case study is presented. Two methods presented here are the Deterministic Approach proposed by Robertson and Wride (1998), and the Probabilistic Approach proposed by Moss and co-workers. Case study of the liquefaction potential evaluation is done for the Golem area, where geotechnical data from CPTU test were collected. The results of analysis in the Golem area show that liquefaction has medium susceptibly to occur. From the analyses, it is shown that the Probabilistic Approach gives more accurate information about the risk of liquefaction than the Deterministic Approach.
文摘Due to rapidly development of information systems, risk and security issues have increased and became a phenomenon that concerns every organization, without considering the size of it. To achieve desired results, managers have to implement methods of evaluating and mitigating risk as part of a process well elaborated. Security risk management helps managers to better control the business practices and improve the business process. An effective risk management process is based on a successful IT security program. This doesn＇t mean that the main goal of an organization＇s risk management process is to protect its IT assets, but to protect the organization and its ability to perform their missions. During this process, managers have to take into consideration risks that can affect the organization and apply the most suitable measures to minimize their impact. The most important task is choosing the best suited method for analyzing the existing risk properly. Several methods have been developed, being classified in quantitative and qualitative approaches of evaluating risk. The purpose of this paper is to present the advantages and disadvantages of each approach taking current needs and opportunities into consideration.
文摘The paper proposes a matrix-based approach that a designer can use to evaluate the sustainability of one or more design solutions in the conceptual phase of a product development process. The methodology is structured in two main phases. In the first one, a data structure, called Augmented-DSM （Design Structure Matrix）, has to be drawn in order to collect design information such as functional links among product components, indicators that provide information about the life cycle of each element, connections with the environment and toward other systems. The matrix is based on a DSM format, where new records were introduced to store and organize different types of data and an editing protocol was formalized. In the second stage, a set of procedures have to be applied in order to evaluate sustainability of a design solution and compare it with the others. The presented procedures, in fact, allow designers to assess a product in its proper characteristics, evaluate a device during its use stage and verify the coherence of links present in the functional model. This new approach is conceived to manage different performance indicators and, as a support tool, it is an attempt to aid designers in a quantitative evaluation.
