IMA Journal of Management Mathematics最新文献_第3页

Probabilistic forecasting of daily COVID-19 admissions using machine learning 使用机器学习对每日新冠肺炎入院人数的概率预测

IF 1.7 3区工程技术

IMA Journal of Management Mathematics Pub Date : 2023-05-14 DOI: 10.1093/imaman/dpad009

B. Rostami-Tabar, Siddharth Arora, J. Rendon-Sanchez, Thanos E. Goltsos

{"title":"Probabilistic forecasting of daily COVID-19 admissions using machine learning","authors":"B. Rostami-Tabar, Siddharth Arora, J. Rendon-Sanchez, Thanos E. Goltsos","doi":"10.1093/imaman/dpad009","DOIUrl":"https://doi.org/10.1093/imaman/dpad009","url":null,"abstract":"\u0000 Accurate forecasts of daily COVID-19 admissions are critical for healthcare planners and decision-makers to better manage scarce resources during and around infection peaks. Numerous studies have focused on forecasting COVID-19 admissions at the national or global levels. Localised predictions are vital, as they allow for resource planning redistribution, but also scarce and harder to get right. Several possible indicators can be used to predict COVID-19 admissions. The inherent variability in the admissions necessitates the generation and evaluation of the forecast distribution of admissions, as opposed to producing only a point forecast. In this study, we propose a quantile regression forest (QRF) model for probabilistic forecasting of daily COVID-19 admissions for a local hospital trust (aggregation of 3 hospitals), up to 7-days ahead, using a multitude of different predictors. We evaluate point forecast accuracy as well as the accuracy of the forecast distribution using appropriate measures. We provide evidence that QRF outperforms univariate time series methods and other more sophisticated benchmarks. Our findings also show that lagged admissions, total positive cases, daily tests performed, and Google grocery and Apple driving are the most salient predictors. Finally, we highlight areas where further research is needed.","PeriodicalId":56296,"journal":{"name":"IMA Journal of Management Mathematics","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49491967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Mathematical modelling of mission-abort policies: a review 任务中止策略的数学建模:综述

IF 1.7 3区工程技术

IMA Journal of Management Mathematics Pub Date : 2023-04-18 DOI: 10.1093/imaman/dpad005

Augusto José Silva Rodrigues, C. Cavalcante, A. R. Alberti, Phillip Scarf, N. M. Alotaibi

{"title":"Mathematical modelling of mission-abort policies: a review","authors":"Augusto José Silva Rodrigues, C. Cavalcante, A. R. Alberti, Phillip Scarf, N. M. Alotaibi","doi":"10.1093/imaman/dpad005","DOIUrl":"https://doi.org/10.1093/imaman/dpad005","url":null,"abstract":"\u0000 This paper reviews works that consider the mathematical modelling of mission-abort policies. In a mission-abort policy (MAP), a valuable, and perhaps vulnerable system performs a mission with two, sometimes conflicting objectives, mission success and system survival, and the purpose of modelling is to determine conditions under which a mission should be aborted. Such problems are important in defence, and emerging in transportation and health management. We classify models by: the nature of the mission and the system; the nature of the return or rescue; type of deterioration model; and the decision objectives. We show that the majority of works consider a model of a one system, one target mission in which the mission is aborted once the hazard of failure reaches a critical level and the operating environment is the same for the outbound and inbound parts of the mission. Typically, the hazard of failure depends on the number of shocks received so far. Our analysis indicates that there has been little modelling development for multiple systems that can multi-task and dependent systems with common-cause failures, for example. We find no evidence that MAPs are used in practice and no works reviewed develop software demonstrators. We think there is considerable scope for modelling applications in transportation (e.g. dynamic train re-scheduling, last-mile logistics) and medical treatments, and MAPs may be more general than the literature that we have reviewed suggests.","PeriodicalId":56296,"journal":{"name":"IMA Journal of Management Mathematics","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48222100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Advances in inverse data envelopment analysis: empowering performance assessment 逆向数据包络分析的进展：增强绩效评估能力

IF 1.7 3区工程技术

IMA Journal of Management Mathematics Pub Date : 2023-04-11 DOI: 10.1093/imaman/dpad004

Ali Emrouznejad, G. R. Amin

引用次数: 0

Eco-efficiency considering NetZero and data envelopment analysis: a critical literature review 考虑NetZero和数据包络分析的生态效率：一篇批评性文献综述

IF 1.7 3区工程技术

IMA Journal of Management Mathematics Pub Date : 2023-03-21 DOI: 10.1093/imaman/dpad002

Ali Emrouznejad, M. Marra, Guo-liang Yang, Maria Michali

{"title":"Eco-efficiency considering NetZero and data envelopment analysis: a critical literature review","authors":"Ali Emrouznejad, M. Marra, Guo-liang Yang, Maria Michali","doi":"10.1093/imaman/dpad002","DOIUrl":"https://doi.org/10.1093/imaman/dpad002","url":null,"abstract":"We highlight the state-of-the-art in the eco-efficiency measurement using Data Envelopment Analysis, including Malmquist-Luenberger productivity index. We also consider productivity change over time, provide directions for future studies in the field, and gather the most recent policy suggestions for governments, organisations and sectors for reducing CO2 emissions. A structured literature search of the Web of Science academic database reveals 311 papers published between 1989 and 2022. We carry out network analysis of citations to show the evolution of the literature in this research topic. In doing so, we (a) examine the key-route main path of knowledge flows, (b) provide basic bibliometric information about the most active journals and authors, (c) conduct a qualitative in-depth analysis of the identified most important studies and (d) identify the research fronts and relate them to the emerging issues on the topic researched, focusing on the most recent period between 2000 and 2022. Based on the insights of the literature review, the second part of this paper critically analyses the papers on the key-route (main path) of this subject. This review can be used as guidance and a starting point for researchers and practitioners that want to further investigate optimal policies to reach NetZero.","PeriodicalId":56296,"journal":{"name":"IMA Journal of Management Mathematics","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45670366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

The Structural Basis for Metal Ion Transport in the SLC11/NRAMP Family. SLC11/NRAMP 家族金属离子转运的结构基础

IF 1.2 3区工程技术

IMA Journal of Management Mathematics Pub Date : 2022-12-21 DOI: 10.2533/chimia.2022.1005

Cristina Manatschal, Raimund Dutzler

{"title":"The Structural Basis for Metal Ion Transport in the SLC11/NRAMP Family.","authors":"Cristina Manatschal, Raimund Dutzler","doi":"10.2533/chimia.2022.1005","DOIUrl":"10.2533/chimia.2022.1005","url":null,"abstract":"<p><p>The SLC11/NRAMP proteins constitute a conserved family of metal ion transporters that are expressed in all kingdoms of life. In humans, the two paralogs DMT1 and NRMP1 play an important role in iron homeostasis and the defense against pathogens. SLC11 transporters have evolved an exquisite selectivity for transition metal ions, which facilitates their efficient transport from a large background of Ca2+ and Mg2+. This is accomplished by the evolution of a conserved binding site, which contains besides promiscuous hard ligands, a methionine acting as soft ligand that exclusively coordinates transition metals and thus contributes to the exclusion of alkaline earth metal ions. This site is altered in a branch of prokaryotic family members, which are capable of transporting Mg2+, where the removal of the coordinating methionine and the accompanying expansion of the binding pocket captures this small ion in a hydrated state. The disposition of titratable residues in H+-coupled transition metal ion transporters, that are absent in uncoupled Mg2+ transporters, sheds light on potential coupling mechanisms. In combination, the discussed work has revealed detailed insight into transition metal ion transport and provides a basis for the development of inhibitors of DMT1 as strategy against iron overload disorders.</p>","PeriodicalId":56296,"journal":{"name":"IMA Journal of Management Mathematics","volume":"24 1","pages":"1005-1010"},"PeriodicalIF":1.2,"publicationDate":"2022-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83059928","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Channel encroachment strategy through pure online or combined offline retailing 通过纯线上或结合线下零售的渠道侵占策略

IF 1.7 3区工程技术

IMA Journal of Management Mathematics Pub Date : 2022-12-06 DOI: 10.1093/imaman/dpac014

Sheng Chen, Ruidong Zhao

{"title":"Channel encroachment strategy through pure online or combined offline retailing","authors":"Sheng Chen, Ruidong Zhao","doi":"10.1093/imaman/dpac014","DOIUrl":"https://doi.org/10.1093/imaman/dpac014","url":null,"abstract":"\u0000 With the rise of e-commerce, an increasing number of retailers concentrate on the online channel to sell their products (strategy O), while some retailers select online and offline combined retailing. That is, the retailers introduce an offline experience store in addition to their online channels (strategy B). However, there is little literature on which strategies are better when a retailer’s intrusion is considered. This paper constructs a competitive system in which the incumbent is a well-established pure online retailer and the new entrant will decide which strategy to select, strategy O or strategy B. The hotelling model is applied to represent the competitive market of both retailers through consumers’ asymmetrical preference for products, and Nash games under two strategies are built. Through comparing equilibrium solutions, we show that when consumers prefer the incumbent’s product, Online and offline retailing is an effective strategy for the new entrant to compete with the incumbent. Meanwhile, the incumbent’s advantage does not always benefit him. Consumers’ asymmetrical preference for products may intensify the competition between them and hurt their profits, but the new entrant can benefit from providing offline retailing under most cases.","PeriodicalId":56296,"journal":{"name":"IMA Journal of Management Mathematics","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2022-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45297750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Strategic joining rules in unobservable queues with dynamic service rate 具有动态服务率的不可观测队列中的策略加入规则

IF 1.7 3区工程技术

IMA Journal of Management Mathematics Pub Date : 2022-12-05 DOI: 10.1093/imaman/dpac013

Shuangfeng Ma, Wei Guo

引用次数: 1

Process mean selection and price differentiation in an imperfectly segmented market for a risk-averse firm 风险规避企业不完全细分市场中的过程均值选择与价格差异

IF 1.7 3区工程技术

IMA Journal of Management Mathematics Pub Date : 2022-10-06 DOI: 10.1093/imaman/dpac012

Syed Asif Raza, Srikrishna Madhumohan Govindaluri

{"title":"Process mean selection and price differentiation in an imperfectly segmented market for a risk-averse firm","authors":"Syed Asif Raza, Srikrishna Madhumohan Govindaluri","doi":"10.1093/imaman/dpac012","DOIUrl":"https://doi.org/10.1093/imaman/dpac012","url":null,"abstract":"\u0000 In this paper we propose an integrated model for optimising the process mean, the price of products, and the production quantity. This optimisation is conducted considering the impact of price differentiation in an imperfectly segmented market where demand leakages are common. The products that are produced by the production process are assigned to two market segments using sampling inspection. For optimisation of the process mean, pricing, and production quantities, a multi-objective model is formulated that maximises (i) The expected total risk-adjusted profit across segments for a risk-tolerant firm, (ii) The satisficing level, that is, the probability of exceeding a target set for total risk-adjusted expected profit, and (iii) The two conflicting objectives, expected total risk-adjusted profit and satisficing level. Depending on the complexity of models, either derivative-based closed form solutions or heuristic solution procedures are developed. The problem finds applications in process industries. A detailed numerical simulation is performed to corroborate the models, and it shows that a higher risk aversion results in a lower total expected risk-adjusted profit but a higher probability of achieving the target profit.","PeriodicalId":56296,"journal":{"name":"IMA Journal of Management Mathematics","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2022-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49127882","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An inverse Data Envelopment Analysis model to consider ratio data and preferences of decision-makers 一个考虑比率数据和决策者偏好的反向数据包络分析模型

IF 1.7 3区工程技术

IMA Journal of Management Mathematics Pub Date : 2022-08-17 DOI: 10.1093/imaman/dpac009

D. Mahla, S. Agarwal, G. R. Amin, T. Mathur

引用次数: 1

Planning and scheduling of a parallel-machine production system subject to disruptions and physical distancing 规划和调度受干扰和物理距离影响的并行机器生产系统

IF 1.7 3区工程技术

IMA Journal of Management Mathematics Pub Date : 2022-08-16 DOI: 10.1093/imaman/dpac010

M. R. Bazargan-Lari, S. Taghipour, A. Zaretalab, M. Sharifi

{"title":"Planning and scheduling of a parallel-machine production system subject to disruptions and physical distancing","authors":"M. R. Bazargan-Lari, S. Taghipour, A. Zaretalab, M. Sharifi","doi":"10.1093/imaman/dpac010","DOIUrl":"https://doi.org/10.1093/imaman/dpac010","url":null,"abstract":"\u0000 This paper aims to quantify the effects of production disruptions and physical distancing constraints due to the pandemic in a parallel-machine production environment. The machines are non-identical and are utilized for producing a finite set of jobs (parts) in a plastic injection molding production. The production process is subject to random production downtime disruptions. A mixed-integer linear programming (MILP) model is developed for optimizing the joint production plan and schedule, which maximizes the production’s total benefit. The model is utilized to plan and schedule a set of 17 machines in a Canadian manufacturing company. To explore the effects of physical distancing and production disruptions on the production’s total net profit, four different scenarios for normal operation and production during the pandemic, with and without production downtimes, are considered. A genetic algorithm is utilized to solve the model. The results show that considering machines’ random breakdowns and physical distancing individually reduces the total profit of the production by 71.58% and 57.98%, respectively; while their joint effect results in a 88.54% reduction in the annual net profit.","PeriodicalId":56296,"journal":{"name":"IMA Journal of Management Mathematics","volume":"1 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2022-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41500310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1