Pub Date : 2018-07-06DOI: 10.1504/IJMOR.2018.10013171
P. Majee, C. Nahak
In this paper, we introduce the concept of semi-η-pseudomonotonicity for vector set-valued mappings. Using this concept, and utilising KKM technique and Nadler's Lemma, we establish some existence results for the new generalised mixed vector variational-like inequality problem in reflexive Banach spaces. Our results are the extension and improvement of some of the results given by Plubtieng and Thammathiwat (2014). Few examples are given to justify our new findings.
{"title":"New generalised mixed vector variational-like inequalities with semi-η-pseudomonotonicity","authors":"P. Majee, C. Nahak","doi":"10.1504/IJMOR.2018.10013171","DOIUrl":"https://doi.org/10.1504/IJMOR.2018.10013171","url":null,"abstract":"In this paper, we introduce the concept of semi-η-pseudomonotonicity for vector set-valued mappings. Using this concept, and utilising KKM technique and Nadler's Lemma, we establish some existence results for the new generalised mixed vector variational-like inequality problem in reflexive Banach spaces. Our results are the extension and improvement of some of the results given by Plubtieng and Thammathiwat (2014). Few examples are given to justify our new findings.","PeriodicalId":306451,"journal":{"name":"Int. J. Math. Oper. Res.","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128461644","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}
Pub Date : 2018-07-06DOI: 10.1504/IJMOR.2018.10013176
M. L. Sam, A. Saptari, M. Salleh, E. Mohamad
This research discusses comparison of linear programming (LP) and integer linear programming (ILP). Two techniques to solve LP, simplex method and interior-point method were introduced. For ILP, available algorithms can be classified into exact algorithms and heuristic algorithms. Three criteria were used to evaluate the characteristics: time complexity, problem size and computational time. Simplex method is effective to solve small sized problems with less number of iterations while interior-point method was recommended for large sized problems due to its excellent performance and shorter computational time than simplex method. Exact algorithms are suitable for small sized problems and attain optimal solution in reasonable computational time. Meanwhile, heuristics outperform exact algorithms in solving large sized problem where it can obtain near optimal solution in an acceptable computational time. Heuristics are not guaranteed to obtain optimal solutions, compared to exact algorithms.
{"title":"Comparison between linear programming and integer linear programming: a review","authors":"M. L. Sam, A. Saptari, M. Salleh, E. Mohamad","doi":"10.1504/IJMOR.2018.10013176","DOIUrl":"https://doi.org/10.1504/IJMOR.2018.10013176","url":null,"abstract":"This research discusses comparison of linear programming (LP) and integer linear programming (ILP). Two techniques to solve LP, simplex method and interior-point method were introduced. For ILP, available algorithms can be classified into exact algorithms and heuristic algorithms. Three criteria were used to evaluate the characteristics: time complexity, problem size and computational time. Simplex method is effective to solve small sized problems with less number of iterations while interior-point method was recommended for large sized problems due to its excellent performance and shorter computational time than simplex method. Exact algorithms are suitable for small sized problems and attain optimal solution in reasonable computational time. Meanwhile, heuristics outperform exact algorithms in solving large sized problem where it can obtain near optimal solution in an acceptable computational time. Heuristics are not guaranteed to obtain optimal solutions, compared to exact algorithms.","PeriodicalId":306451,"journal":{"name":"Int. J. Math. Oper. Res.","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126255698","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}
Pub Date : 2018-07-06DOI: 10.1504/IJMOR.2018.10013169
Seyed Hojat Pakzad Moghadam, Farhad Salehian, Seyed Esa Hosseini, H. Mina
Cellular manufacturing is one of the most common and popular methods in order to take advantage of group technology. Of particular interest, applying cellular manufacturing systems (CMSs) increases the efficiency of the applied transportation system by designing an efficient working floor. Controlling the amount of material handling, results in lower cost and energy required to transport materials/products. Hence, CMS are under consideration in the study at hand. Regarding a hybrid CMS, proper manufacturing systems such as single machines, flow shops, job-shops and open shops are applied between and within cells to harmonise the whole manufacturing procedure. A special case of hybrid CMS, referred to as hierarchical CMS is investigated in this paper. In a HCMS not only machines are placed in several interior cells, but also interior cells themselves must be located in exterior ones. Finally a mixed integer nonlinear programming mathematical model is presented and validated through numerical results.
{"title":"A hierarchical cellular manufacturing system","authors":"Seyed Hojat Pakzad Moghadam, Farhad Salehian, Seyed Esa Hosseini, H. Mina","doi":"10.1504/IJMOR.2018.10013169","DOIUrl":"https://doi.org/10.1504/IJMOR.2018.10013169","url":null,"abstract":"Cellular manufacturing is one of the most common and popular methods in order to take advantage of group technology. Of particular interest, applying cellular manufacturing systems (CMSs) increases the efficiency of the applied transportation system by designing an efficient working floor. Controlling the amount of material handling, results in lower cost and energy required to transport materials/products. Hence, CMS are under consideration in the study at hand. Regarding a hybrid CMS, proper manufacturing systems such as single machines, flow shops, job-shops and open shops are applied between and within cells to harmonise the whole manufacturing procedure. A special case of hybrid CMS, referred to as hierarchical CMS is investigated in this paper. In a HCMS not only machines are placed in several interior cells, but also interior cells themselves must be located in exterior ones. Finally a mixed integer nonlinear programming mathematical model is presented and validated through numerical results.","PeriodicalId":306451,"journal":{"name":"Int. J. Math. Oper. Res.","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130652804","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}
Pub Date : 2018-07-06DOI: 10.1504/IJMOR.2018.10013178
Amiya Biswas, A. K. Bhunia, A. Shaikh
In this paper, an approach based on genetic algorithm has been proposed for solving multi-objective unbalanced assignment problems with restriction of job(s) to different agents which may arise due to the inability/poor efficiency of performing certain jobs by some agents dealing with an additional constraint on the maximum number of jobs that can be performed by an agent. As the cost and time are considered as the most important factors for managerial decision in economic/industrial establishments, so here the total cost of assignment of jobs to agents and the total time of completion of jobs by the agents are considered as the two prime objectives. This gives rise to an NP-hard 0-1 programming problem and to solve this problem, we have equipped NSGA-II with a newly developed crossover having the capability of repairing infeasible solution and two new mutation schemes. Also, for comparison of the results obtained from this algorithm, some other variants of this algorithm with existing crossover and mutation schemes have been considered. Finally, to illustrate the performance of proposed approach, a set of test problems have been solved and the results have been analysed for different variants of NSGA-II and some potential future research directions has been discussed.
{"title":"Multi-objective unbalanced assignment problem with restriction of jobs to agents via NSGA-II","authors":"Amiya Biswas, A. K. Bhunia, A. Shaikh","doi":"10.1504/IJMOR.2018.10013178","DOIUrl":"https://doi.org/10.1504/IJMOR.2018.10013178","url":null,"abstract":"In this paper, an approach based on genetic algorithm has been proposed for solving multi-objective unbalanced assignment problems with restriction of job(s) to different agents which may arise due to the inability/poor efficiency of performing certain jobs by some agents dealing with an additional constraint on the maximum number of jobs that can be performed by an agent. As the cost and time are considered as the most important factors for managerial decision in economic/industrial establishments, so here the total cost of assignment of jobs to agents and the total time of completion of jobs by the agents are considered as the two prime objectives. This gives rise to an NP-hard 0-1 programming problem and to solve this problem, we have equipped NSGA-II with a newly developed crossover having the capability of repairing infeasible solution and two new mutation schemes. Also, for comparison of the results obtained from this algorithm, some other variants of this algorithm with existing crossover and mutation schemes have been considered. Finally, to illustrate the performance of proposed approach, a set of test problems have been solved and the results have been analysed for different variants of NSGA-II and some potential future research directions has been discussed.","PeriodicalId":306451,"journal":{"name":"Int. J. Math. Oper. Res.","volume":"128 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133951919","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}
Pub Date : 2018-07-06DOI: 10.1504/IJMOR.2018.10013180
C. D. Nandakumar, S. Srinivasan, R. Sathiyamoorthi
In this paper, a production process is considered which requires two kinds of raw materials as inputs to make a product. The two kinds of raw materials are stored separately. During the time of crisis like non-availability of the raw materials due to scarcity or delayed delivery or for some other reasons, the reserve stocks are utilised to continue the production process, as a result; the level of reserve stocks would come down and finally may go void. This may result into production halt. To avoid this situation, a reorder is made to maintain the level of reserve inventory as soon as the reserve level touches a particular level called the threshold level. Using the shock model and cumulative damage process technique, a stochastic model is derived to find the threshold level or the time of reordering, which helps the production system to eliminate the holding cost on excessive raw materials and also the loss arising from the shortage of raw materials. Numerical illustrations are provided.
{"title":"Evaluation of reordering time in a manufacturing inventory division","authors":"C. D. Nandakumar, S. Srinivasan, R. Sathiyamoorthi","doi":"10.1504/IJMOR.2018.10013180","DOIUrl":"https://doi.org/10.1504/IJMOR.2018.10013180","url":null,"abstract":"In this paper, a production process is considered which requires two kinds of raw materials as inputs to make a product. The two kinds of raw materials are stored separately. During the time of crisis like non-availability of the raw materials due to scarcity or delayed delivery or for some other reasons, the reserve stocks are utilised to continue the production process, as a result; the level of reserve stocks would come down and finally may go void. This may result into production halt. To avoid this situation, a reorder is made to maintain the level of reserve inventory as soon as the reserve level touches a particular level called the threshold level. Using the shock model and cumulative damage process technique, a stochastic model is derived to find the threshold level or the time of reordering, which helps the production system to eliminate the holding cost on excessive raw materials and also the loss arising from the shortage of raw materials. Numerical illustrations are provided.","PeriodicalId":306451,"journal":{"name":"Int. J. Math. Oper. Res.","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128860726","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}
Pub Date : 2018-07-06DOI: 10.1504/IJMOR.2018.10013170
S. Haddadi, Meryem Cheraitia, A. Salhi
The set covering problem (SCP) is a well-known computationally intractable problem. We suggest here a two-phase heuristic to solve it. The first phase reduces substantially the size of the given SCP by removing some variables; the second phase applies a simple Lagrangian heuristic applied to the reduced problem. Construction and improvement heuristics are embedded in the Lagrangian solution approach. The construction heuristic provides good covers by solving small SCPs. The improvement heuristic inserts these covers into larger ones from which better covers are extracted, again by solving different but also small SCPs. The novelty lies in the reduction of the problem size by an effective variable-fixing heuristic, which, in practice, eliminates up to 95% of the variables of the problem without sacrificing the solution quality. Extensive computational and comparative results are presented.
{"title":"A two-phase heuristic for set covering","authors":"S. Haddadi, Meryem Cheraitia, A. Salhi","doi":"10.1504/IJMOR.2018.10013170","DOIUrl":"https://doi.org/10.1504/IJMOR.2018.10013170","url":null,"abstract":"The set covering problem (SCP) is a well-known computationally intractable problem. We suggest here a two-phase heuristic to solve it. The first phase reduces substantially the size of the given SCP by removing some variables; the second phase applies a simple Lagrangian heuristic applied to the reduced problem. Construction and improvement heuristics are embedded in the Lagrangian solution approach. The construction heuristic provides good covers by solving small SCPs. The improvement heuristic inserts these covers into larger ones from which better covers are extracted, again by solving different but also small SCPs. The novelty lies in the reduction of the problem size by an effective variable-fixing heuristic, which, in practice, eliminates up to 95% of the variables of the problem without sacrificing the solution quality. Extensive computational and comparative results are presented.","PeriodicalId":306451,"journal":{"name":"Int. J. Math. Oper. Res.","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125721133","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}
Pub Date : 2018-06-05DOI: 10.1504/IJMOR.2018.10011880
D. Acharya, M. Basu, Atanu Das
The fixed-charge transportation problem (FCTP) is still a challenging problem in the field of mathematical programming. In this paper, we consider fixed-charge transportation problem with logarithmic objective function. In the absence of any suitable algorithm to obtain the solution of this type of nonlinear transportation problem, we discuss the advantage of polynomial approximation. There exists a major difference between the two problems that the variables in the polynomial transportation problem have no upper bound but in the logarithmic transportation problem they are bounded. Using the expansion of logarithm we show the resemblance between the structural behaviour of linear and fixed-charge transportation problems. We illustrate a numerical example in support of the developed method.
{"title":"On logarithmic fixed-charge transportation problem","authors":"D. Acharya, M. Basu, Atanu Das","doi":"10.1504/IJMOR.2018.10011880","DOIUrl":"https://doi.org/10.1504/IJMOR.2018.10011880","url":null,"abstract":"The fixed-charge transportation problem (FCTP) is still a challenging problem in the field of mathematical programming. In this paper, we consider fixed-charge transportation problem with logarithmic objective function. In the absence of any suitable algorithm to obtain the solution of this type of nonlinear transportation problem, we discuss the advantage of polynomial approximation. There exists a major difference between the two problems that the variables in the polynomial transportation problem have no upper bound but in the logarithmic transportation problem they are bounded. Using the expansion of logarithm we show the resemblance between the structural behaviour of linear and fixed-charge transportation problems. We illustrate a numerical example in support of the developed method.","PeriodicalId":306451,"journal":{"name":"Int. J. Math. Oper. Res.","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133736181","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}
Pub Date : 2018-06-05DOI: 10.1504/IJMOR.2018.10011877
P. S. Dharmapala
Bootstrapping of DEA efficiency scores came into being under the criticism that DEA input/output data may contain random error, and as a result the efficient frontier may be warped by statistical noise. Since the publication of the seminal paper by Simar and Wilson (1998), several researchers have carried out bootstrapping the DEA frontier, re-computing the efficiency scores after correcting the biases and developing confidence intervals for bias-corrected scores. We view bias-correction in DEA efficiency scores from a different perspective by randomising the efficiency scores that follow underlying beta distributions. In a step-by-step process, using the simulated beta samples, we show how to correct the biases of individual scores, construct confidence intervals for the bias-corrected mean scores and derive some statistical results for the estimators used in the process. Finally, we demonstrate this method by applying it to a set of banks.
{"title":"Bias-correction in DEA efficiency scores using simulated beta samples: an alternative view of bootstrapping in DEA","authors":"P. S. Dharmapala","doi":"10.1504/IJMOR.2018.10011877","DOIUrl":"https://doi.org/10.1504/IJMOR.2018.10011877","url":null,"abstract":"Bootstrapping of DEA efficiency scores came into being under the criticism that DEA input/output data may contain random error, and as a result the efficient frontier may be warped by statistical noise. Since the publication of the seminal paper by Simar and Wilson (1998), several researchers have carried out bootstrapping the DEA frontier, re-computing the efficiency scores after correcting the biases and developing confidence intervals for bias-corrected scores. We view bias-correction in DEA efficiency scores from a different perspective by randomising the efficiency scores that follow underlying beta distributions. In a step-by-step process, using the simulated beta samples, we show how to correct the biases of individual scores, construct confidence intervals for the bias-corrected mean scores and derive some statistical results for the estimators used in the process. Finally, we demonstrate this method by applying it to a set of banks.","PeriodicalId":306451,"journal":{"name":"Int. J. Math. Oper. Res.","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133084789","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}
Pub Date : 2018-06-05DOI: 10.1504/IJMOR.2018.10011881
Kenneth Barroga
Although Rao diversity coefficient (Rao DIVC) is sensitive to the differences among species, a gap still remains in investigating how the communities are affected when the dissimilarity among the species are in terms of its morphometry and taxonomy. I studied the effect of using species taxonomic classification and species morphometrical traits in the computation of Rao DIVC in assessing diversity of ecological communities. I utlised the Mahalanobis distance for measuring the variation of species morphometry. As for species taxonomy, I employed the method by Warwick and Clarke (1995). When the calculated Rao DIVCs, double principal coordinate analysis and co-inertia analysis outputs were compared, I discovered that Rao DIVCs accounting species morphometry (Rsm) and species taxonomy (Rst) yielded different results and interpretation. Rsm clearly showed more the variation among communities but contributed less in the analysis, whereas Rst showed more clearly the clusters between the communities which make the interpretation easier.
{"title":"A mathematical investigation of Rao diversity coefficients among the communities according to species morphometry and species taxonomy","authors":"Kenneth Barroga","doi":"10.1504/IJMOR.2018.10011881","DOIUrl":"https://doi.org/10.1504/IJMOR.2018.10011881","url":null,"abstract":"Although Rao diversity coefficient (Rao DIVC) is sensitive to the differences among species, a gap still remains in investigating how the communities are affected when the dissimilarity among the species are in terms of its morphometry and taxonomy. I studied the effect of using species taxonomic classification and species morphometrical traits in the computation of Rao DIVC in assessing diversity of ecological communities. I utlised the Mahalanobis distance for measuring the variation of species morphometry. As for species taxonomy, I employed the method by Warwick and Clarke (1995). When the calculated Rao DIVCs, double principal coordinate analysis and co-inertia analysis outputs were compared, I discovered that Rao DIVCs accounting species morphometry (Rsm) and species taxonomy (Rst) yielded different results and interpretation. Rsm clearly showed more the variation among communities but contributed less in the analysis, whereas Rst showed more clearly the clusters between the communities which make the interpretation easier.","PeriodicalId":306451,"journal":{"name":"Int. J. Math. Oper. Res.","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128749978","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}
Pub Date : 2018-06-05DOI: 10.1504/IJMOR.2018.10011878
Promila Kumar, Jyoti
This paper deals with non-differentiable multi-objective semi-infinite programming problem. It is a problem of simultaneous minimisation of finitely many scalar valued functions subject to an arbitrary (possibly infinite) set of constraints. Non-differentiability enters, due to the square root of a quadratic form which appears in the objective functional. Concept of efficiency of order m has been extended to the above stated problem. In order to study this new solution concept, the notion of ρ-invexity of order m is also proposed which is utilised to establish sufficient optimality conditions for the non-differentiable multi-objective semi-infinite programming problem. Mond-Weir type of dual is proposed for which weak, strong and strict converse duality theorems are established.
{"title":"Duality for non-differentiable multi-objective semi-infinite programming for higher order invex functions","authors":"Promila Kumar, Jyoti","doi":"10.1504/IJMOR.2018.10011878","DOIUrl":"https://doi.org/10.1504/IJMOR.2018.10011878","url":null,"abstract":"This paper deals with non-differentiable multi-objective semi-infinite programming problem. It is a problem of simultaneous minimisation of finitely many scalar valued functions subject to an arbitrary (possibly infinite) set of constraints. Non-differentiability enters, due to the square root of a quadratic form which appears in the objective functional. Concept of efficiency of order m has been extended to the above stated problem. In order to study this new solution concept, the notion of ρ-invexity of order m is also proposed which is utilised to establish sufficient optimality conditions for the non-differentiable multi-objective semi-infinite programming problem. Mond-Weir type of dual is proposed for which weak, strong and strict converse duality theorems are established.","PeriodicalId":306451,"journal":{"name":"Int. J. Math. Oper. Res.","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125600217","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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