The purpose of this paper is to introduce a new method for the determination of the values of the first-order Biochemical Oxygen Demand (BOD) model coefficients (k and L).Cubic spline interpolation and MATLAB were used for that purpose after the experimental and theoretical BOD values were made dimensionless. Experimental BOD values taken from the literature are made dimensionless by dividing them by experimental BOD1 through BOD5. Theoretical BOD values are made dimensionless by dividing them by the theoretical BOD1 through BOD5 for different theoretical k values. Experimental dimensionless BOD values are connected smoothly using cubic spline method. Using MATLAB, the closest theoretical dimensionless BOD curve to the cubic spline curve is selected and used for the determination of k and L. The closest curve is the one that has the same area under it as to that under the cubic spline curve with the areas that lie between the two curves being the smallest. The new method has proved to give more accurate values after it has been compared with a number of other methods used for that purpose.The new method produced the smallest error and the highest coefficient of determination than the other methods used. The newly introduced method is expected to replace all other methods, as these methods give different values for k and L depending on the method used.
{"title":"The Use of Cubic Splines and MATLAB for the Determination of BOD First-Order Model Coefficients","authors":"B. Ammary, La’aly A. Al-Samrraie","doi":"10.14525/JJCE.10.3.3608","DOIUrl":"https://doi.org/10.14525/JJCE.10.3.3608","url":null,"abstract":"The purpose of this paper is to introduce a new method for the determination of the values of the first-order Biochemical Oxygen Demand (BOD) model coefficients (k and L).Cubic spline interpolation and MATLAB were used for that purpose after the experimental and theoretical BOD values were made dimensionless. Experimental BOD values taken from the literature are made dimensionless by dividing them by experimental BOD1 through BOD5. Theoretical BOD values are made dimensionless by dividing them by the theoretical BOD1 through BOD5 for different theoretical k values. Experimental dimensionless BOD values are connected smoothly using cubic spline method. Using MATLAB, the closest theoretical dimensionless BOD curve to the cubic spline curve is selected and used for the determination of k and L. The closest curve is the one that has the same area under it as to that under the cubic spline curve with the areas that lie between the two curves being the smallest. The new method has proved to give more accurate values after it has been compared with a number of other methods used for that purpose.The new method produced the smallest error and the highest coefficient of determination than the other methods used. The newly introduced method is expected to replace all other methods, as these methods give different values for k and L depending on the method used.","PeriodicalId":51814,"journal":{"name":"Jordan Journal of Civil Engineering","volume":"10 1","pages":"352-366"},"PeriodicalIF":1.1,"publicationDate":"2016-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66631638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper aims at designing a model to relate construction project performance to Sudanese construction organization performance using financial and non-financial metrics along with objective and subjective measures. The study used an extensive literature review in the field of construction management and professional advice in order to design a questionnaire for data collection. EQS6.2 software was used for data analysis and model fit evaluation. The model showed a strong relationship between construction project performance and Sudanese construction organization performance, as well as strong relationships between construction project performance and its metrics ("project profitability", "external customer satisfaction" and "internal customer satisfaction"). Furthermore, strong relationships were found between Sudanese construction organization performance and its metrics ("financial", "customer", "internal business" and "learning and growth" perspectives).
{"title":"Effect of Project Performance on Organization Performance in Sudanese Construction Industry","authors":"H. A. Sulieman, S. M. Adlan","doi":"10.14525/JJCE.10.3.3603","DOIUrl":"https://doi.org/10.14525/JJCE.10.3.3603","url":null,"abstract":"This paper aims at designing a model to relate construction project performance to Sudanese construction organization performance using financial and non-financial metrics along with objective and subjective measures. The study used an extensive literature review in the field of construction management and professional advice in order to design a questionnaire for data collection. EQS6.2 software was used for data analysis and model fit evaluation. The model showed a strong relationship between construction project performance and Sudanese construction organization performance, as well as strong relationships between construction project performance and its metrics (\"project profitability\", \"external customer satisfaction\" and \"internal customer satisfaction\"). Furthermore, strong relationships were found between Sudanese construction organization performance and its metrics (\"financial\", \"customer\", \"internal business\" and \"learning and growth\" perspectives).","PeriodicalId":51814,"journal":{"name":"Jordan Journal of Civil Engineering","volume":"38 1","pages":"297-304"},"PeriodicalIF":1.1,"publicationDate":"2016-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66631467","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The application of hedging rules in reservoir operation has been established as one of the important advances in the field of reservoir operation studies during the past three decades. Hedging rules distribute the deficits over a longer duration to minimize the impact of deficits. Thus, hedging provides the insurance of highvalued water uses, where reservoirs experience uncertain inflows. Formulating different forms of hedging rules and proposing appropriate objective functions that adequately describe the trade-off among the operational performance indicators have been attempted for water supply and irrigation release from reservoirs. Research on hedging rule-based operation of reservoirs for hydro-power generation has not yet gained sufficient attention, probably due to its complexity due to non-linearity. In this study, hedging rules are formulated for Indira Sagar reservoir for hydro-power generation. Discrete phased hedging rule and twopoint linear hedging rule are developed and demonstrated in this research. While the two-point linear hedging rule is one of the simple hedging rules, the discrete phased hedging rule is a more realistic rule as it will facilitate better planning of alternative sources of power generation or rationing. The results indicate the advantages of applying the hedging rules over the standard operating policy.
{"title":"Application of Hedging Rules in the Operation of Hydro - Power Reservoirs","authors":"K. Sasireka, T. Neelakantan","doi":"10.14525/JJCE.10.3.3604","DOIUrl":"https://doi.org/10.14525/JJCE.10.3.3604","url":null,"abstract":"The application of hedging rules in reservoir operation has been established as one of the important advances in the field of reservoir operation studies during the past three decades. Hedging rules distribute the deficits over a longer duration to minimize the impact of deficits. Thus, hedging provides the insurance of highvalued water uses, where reservoirs experience uncertain inflows. Formulating different forms of hedging rules and proposing appropriate objective functions that adequately describe the trade-off among the operational performance indicators have been attempted for water supply and irrigation release from reservoirs. Research on hedging rule-based operation of reservoirs for hydro-power generation has not yet gained sufficient attention, probably due to its complexity due to non-linearity. In this study, hedging rules are formulated for Indira Sagar reservoir for hydro-power generation. Discrete phased hedging rule and twopoint linear hedging rule are developed and demonstrated in this research. While the two-point linear hedging rule is one of the simple hedging rules, the discrete phased hedging rule is a more realistic rule as it will facilitate better planning of alternative sources of power generation or rationing. The results indicate the advantages of applying the hedging rules over the standard operating policy.","PeriodicalId":51814,"journal":{"name":"Jordan Journal of Civil Engineering","volume":"14 1","pages":"305-312"},"PeriodicalIF":1.1,"publicationDate":"2016-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66631502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Design and Construction Defects Influencing Residential Building Maintenance in Nigeria","authors":"B. S. Waziri","doi":"10.14525/JJCE.10.3.3605","DOIUrl":"https://doi.org/10.14525/JJCE.10.3.3605","url":null,"abstract":"","PeriodicalId":51814,"journal":{"name":"Jordan Journal of Civil Engineering","volume":"10 1","pages":"313-323"},"PeriodicalIF":1.1,"publicationDate":"2016-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66631522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study evaluates the shear capacity of reinforced concrete (RC) membrane elements subjected to pure inplane shear stresses at different levels of loading. These elements are shown to fail in four different modes. A model is proposed for the shear capacity of these membrane elements that can be computed by direct simple expressions without the need to any iterative process as is usually the case in existing models. Failure in these membrane elements is generally preceded by the formation of two or more major critical cracks assumed herein to propagate in a direction normal to the principal tensile stresses in the concrete. At each stage of loading, the major critical cracks are shown to open at an optimum angle that corresponds to the least shearing resistance to external loading. Major cracks as well as ultimate shear capacity of RC membrane elements are shown to occur when the contribution of the x-reinforcement to resist shear stresses is equal to that of the y-reinforcement. Experimental results of tests on RC membrane elements subjected to pure inplane shear stresses obtained from literature are used to validate and compare the proposed model with existing models. Examples are provided for the computations of shear capacity by the proposed model for the different modes of failure.
{"title":"Shear Capacity of RC Membrane Elements Subjected to Pure In-Plane Shear Stresses","authors":"M. Al-Zoubi","doi":"10.14525/JJCE.10.3.3606","DOIUrl":"https://doi.org/10.14525/JJCE.10.3.3606","url":null,"abstract":"This study evaluates the shear capacity of reinforced concrete (RC) membrane elements subjected to pure inplane shear stresses at different levels of loading. These elements are shown to fail in four different modes. A model is proposed for the shear capacity of these membrane elements that can be computed by direct simple expressions without the need to any iterative process as is usually the case in existing models. Failure in these membrane elements is generally preceded by the formation of two or more major critical cracks assumed herein to propagate in a direction normal to the principal tensile stresses in the concrete. At each stage of loading, the major critical cracks are shown to open at an optimum angle that corresponds to the least shearing resistance to external loading. Major cracks as well as ultimate shear capacity of RC membrane elements are shown to occur when the contribution of the x-reinforcement to resist shear stresses is equal to that of the y-reinforcement. Experimental results of tests on RC membrane elements subjected to pure inplane shear stresses obtained from literature are used to validate and compare the proposed model with existing models. Examples are provided for the computations of shear capacity by the proposed model for the different modes of failure.","PeriodicalId":51814,"journal":{"name":"Jordan Journal of Civil Engineering","volume":"10 1","pages":"324-338"},"PeriodicalIF":1.1,"publicationDate":"2016-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66631573","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study is focused on the prediction of the asphalt binder complex modulus at various temperatures and various loading frequencies. The master curve approach was used to predict the asphalt binder behavior for a wide range of temperatures and loading frequencies by applying the time-temperature superposition principle for pressure ageing vessel (PAV) aged asphalt binder mixed with different percentages of sasobit asphalt modifier. The complex modulus was measured using the dynamic shear rheometer (DSR) with a wide range of loading frequencies (0.1 Hz-10 Hz) and a wide range of testing temperatures (16 C-31 C). The results showed an increase in the complex modulus with increasing the loading frequency as well as with increasing the sasobit percentage. However, the results showed a decrease in the complex modulus with increasing the testing temperature. The use of the master curve approach showed a high degree of accuracy in predicting the complex modulus for the asphalt binder.
{"title":"Predicting the Complex Modulus for PAV Aged Asphalt Binder Using a Master Curve Approach for Sasobit Modified Asphalt Binder","authors":"Khalid A. Ghuzlan, M. A. Assi","doi":"10.14525/JJCE.10.3.3610","DOIUrl":"https://doi.org/10.14525/JJCE.10.3.3610","url":null,"abstract":"This study is focused on the prediction of the asphalt binder complex modulus at various temperatures and various loading frequencies. The master curve approach was used to predict the asphalt binder behavior for a wide range of temperatures and loading frequencies by applying the time-temperature superposition principle for pressure ageing vessel (PAV) aged asphalt binder mixed with different percentages of sasobit asphalt modifier. The complex modulus was measured using the dynamic shear rheometer (DSR) with a wide range of loading frequencies (0.1 Hz-10 Hz) and a wide range of testing temperatures (16 C-31 C). The results showed an increase in the complex modulus with increasing the loading frequency as well as with increasing the sasobit percentage. However, the results showed a decrease in the complex modulus with increasing the testing temperature. The use of the master curve approach showed a high degree of accuracy in predicting the complex modulus for the asphalt binder.","PeriodicalId":51814,"journal":{"name":"Jordan Journal of Civil Engineering","volume":"316 1","pages":"390-402"},"PeriodicalIF":1.1,"publicationDate":"2016-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66631764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Every project confronts risk both in financial and technical dimensions. This induces a greater response on the performance of the project. A successful construction project depends on how the project participants compute the actual project performance. A commendable assessment of project performance practice determines the project productivity both quantitatively and qualitatively. Methods of project performance measurement vary among industries. As a contribution to the above, this study equips the project manager with a proficient mode of project performance measurement and the essential promising decisions that head to profit maximization. This intricate study thus facilitates the project manager to compute the project performance on the basis of the effects of Earned Value Management (EVM) indices which are broadly classified as: variance indices, performance indices and miscellaneous or forecast indices. Adopting the Analytical Network Process (ANP) structure model in Super Decision software is a reliable decision making tool. This study indicates that the cost variance (CV) index is prominent among the EVM indices that highly affect the project characteristics, the measurement of which facilitates the required control measures on respective project activities. It also indicates that cost is the major project characteristic, the variation of which immensely affects the project performance. It procures an objective reference for engineering projects by following the selection process of best EVM indices that holds an accurate measure of project performance.
{"title":"Application of Earned Value Management to Compute the Project Performance Using Analytical Network Process","authors":"S. Ramani, N. Sruthi","doi":"10.14525/JJCE.10.1.3541","DOIUrl":"https://doi.org/10.14525/JJCE.10.1.3541","url":null,"abstract":"Every project confronts risk both in financial and technical dimensions. This induces a greater response on the performance of the project. A successful construction project depends on how the project participants compute the actual project performance. A commendable assessment of project performance practice determines the project productivity both quantitatively and qualitatively. Methods of project performance measurement vary among industries. As a contribution to the above, this study equips the project manager with a proficient mode of project performance measurement and the essential promising decisions that head to profit maximization. This intricate study thus facilitates the project manager to compute the project performance on the basis of the effects of Earned Value Management (EVM) indices which are broadly classified as: variance indices, performance indices and miscellaneous or forecast indices. Adopting the Analytical Network Process (ANP) structure model in Super Decision software is a reliable decision making tool. This study indicates that the cost variance (CV) index is prominent among the EVM indices that highly affect the project characteristics, the measurement of which facilitates the required control measures on respective project activities. It also indicates that cost is the major project characteristic, the variation of which immensely affects the project performance. It procures an objective reference for engineering projects by following the selection process of best EVM indices that holds an accurate measure of project performance.","PeriodicalId":51814,"journal":{"name":"Jordan Journal of Civil Engineering","volume":"10 1","pages":"254-265"},"PeriodicalIF":1.1,"publicationDate":"2016-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66631668","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A large number of studies, experiments and practical test projects have been undertaken throughout the world to assess the modifications in the properties of concrete after addition of rubber aggregates. These rubber aggregates are used to replace fine or coarse aggregates in various proportions. This experimental investigation attempts to study the strength properties and non-destructive evaluation of rubberized concrete with coarse aggregates being partially replaced with rubber aggregates from recycled tyres, in order to assess its suitability for use in structural and non-structural components. Effort was also made to determine the change in thermal properties. It was learnt that the inclusion of rubber in concrete makes the material a better thermal insulator, having a lower coefficient of thermal conductivity. This lower thermal conductivity is a property which could be very useful for meeting energy conservation requirements. Attempt was also made to assess the impact resistance of rubberized concrete. A marked improvement in this property was also observed.
{"title":"Thermal Conductivity and Impact Resistance of Concrete Using Partial Replacement of Coarse Aggregate with Rubber","authors":"Venu Malagavelli, R. S. Parmar, P. N. Rao","doi":"10.14525/JJCE.10.2.3533","DOIUrl":"https://doi.org/10.14525/JJCE.10.2.3533","url":null,"abstract":"A large number of studies, experiments and practical test projects have been undertaken throughout the world to assess the modifications in the properties of concrete after addition of rubber aggregates. These rubber aggregates are used to replace fine or coarse aggregates in various proportions. This experimental investigation attempts to study the strength properties and non-destructive evaluation of rubberized concrete with coarse aggregates being partially replaced with rubber aggregates from recycled tyres, in order to assess its suitability for use in structural and non-structural components. Effort was also made to determine the change in thermal properties. It was learnt that the inclusion of rubber in concrete makes the material a better thermal insulator, having a lower coefficient of thermal conductivity. This lower thermal conductivity is a property which could be very useful for meeting energy conservation requirements. Attempt was also made to assess the impact resistance of rubberized concrete. A marked improvement in this property was also observed.","PeriodicalId":51814,"journal":{"name":"Jordan Journal of Civil Engineering","volume":"10 1","pages":"145-162"},"PeriodicalIF":1.1,"publicationDate":"2016-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66631407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study has been conducted to study rework in residential building projects in the West Bank in Palestine. It investigates the cost and causes of rework. A questionnaire survey of 86 contractors from the West Bank in Palestine was performed. 43 rework causes were identified during the research. The study investigates the average of rework cost and the severity of the identified rework causes. 62% of the contractors indicated that the average of rework cost in residential building construction projects that they have experienced during the last five years ranged between 10% and 15% of the original contract cost, which means that rework in residential projects is a severe problem, which should be studied more intensively to be solved in the future. The questionnaire survey also concluded that the most severe causes of rework in residential building projects as identified by the contractors are: poor communication of the client with the consultant, poor communication of the client with the contractor, use of poor quality materials, poor site management and poor communication of the client with the design consultant.
{"title":"Analysis of Rework in Residential Building Projects in Palestine","authors":"I. Mahamid","doi":"10.14525/JJCE.10.1.3536","DOIUrl":"https://doi.org/10.14525/JJCE.10.1.3536","url":null,"abstract":"This study has been conducted to study rework in residential building projects in the West Bank in Palestine. It investigates the cost and causes of rework. A questionnaire survey of 86 contractors from the West Bank in Palestine was performed. 43 rework causes were identified during the research. The study investigates the average of rework cost and the severity of the identified rework causes. 62% of the contractors indicated that the average of rework cost in residential building construction projects that they have experienced during the last five years ranged between 10% and 15% of the original contract cost, which means that rework in residential projects is a severe problem, which should be studied more intensively to be solved in the future. The questionnaire survey also concluded that the most severe causes of rework in residential building projects as identified by the contractors are: poor communication of the client with the consultant, poor communication of the client with the contractor, use of poor quality materials, poor site management and poor communication of the client with the design consultant.","PeriodicalId":51814,"journal":{"name":"Jordan Journal of Civil Engineering","volume":"10 1","pages":"197-208"},"PeriodicalIF":1.1,"publicationDate":"2016-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66631201","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, Finite Element Model (FEM) updating based on a new heuristic algorithmis proposed for damage identification in truss structures. This method updates the dynamic properties of the damaged and undamaged state of a structure to identify the presence, location and magnitude of the damage in structural members. Imperialist Competitive Algorithm (ICA), which is one of the most efficient heuristic methods, is used to minimize the objective function which is based on dynamic properties of the structure. Damage in structures is caused by the reduction in stiffness of specific members, especially in Young's modulus. The capability and efficiency of this method to identify damage using frequencies and mode shapes are demonstrated by means of several numerical examples. Results show the superiority and effectiveness of the proposed method.
{"title":"Damage Identification in Truss Structures Using Finite Element Model Updating and Imperialist Competitive Algorithm","authors":"H. Ghaffarzadeh, F. Raeisi","doi":"10.14525/JJCE.10.1.3542","DOIUrl":"https://doi.org/10.14525/JJCE.10.1.3542","url":null,"abstract":"In this paper, Finite Element Model (FEM) updating based on a new heuristic algorithmis proposed for damage identification in truss structures. This method updates the dynamic properties of the damaged and undamaged state of a structure to identify the presence, location and magnitude of the damage in structural members. Imperialist Competitive Algorithm (ICA), which is one of the most efficient heuristic methods, is used to minimize the objective function which is based on dynamic properties of the structure. Damage in structures is caused by the reduction in stiffness of specific members, especially in Young's modulus. The capability and efficiency of this method to identify damage using frequencies and mode shapes are demonstrated by means of several numerical examples. Results show the superiority and effectiveness of the proposed method.","PeriodicalId":51814,"journal":{"name":"Jordan Journal of Civil Engineering","volume":"276 1","pages":"266-277"},"PeriodicalIF":1.1,"publicationDate":"2016-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66631822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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