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Study on the Problem of Multistage Vaccine Production and Allocation with Capacity Constraints

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Journal of Systems Science & Complexity 2023年第5期36卷 2046-2066页

作者： HAN Qianqian ZHANG Yuwei li Zhenping fang yong School of Management and Engineering Capital University of Economics and BusinessBeijing 100070China School of Information Beijing Wuzi UniversityBeijing 101149China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China

Vaccination is the best way to build an immune barrier to control a new infectious disease.Considering the limited production capacity at the initial stage of vaccine production,the problem of multistage vaccine production and allocation is studied under the policy of free treatment for infected patients by the government.Given the population and infection rates of different regions and the vaccine production capacity of each stage,an integer programming model is established to minimize the sum of production-and-vaccination cost and treatment cost of infected patients,which is solved by the GUROBI solver.The correctness of the model is verified by simulation,and the necessity of considering the treatment cost of infected patients in the objective function is further analyzed,which confirmed the correctness of the free treatment policy for patients in China.A heuristic algorithm is designed to solve the large-scale problem and numerical experiments are conducted to verify the efficiency of this algorithm.Furthermore,based on the sensitivity analysis results of parameters,the optimal vaccine production and allocation strategy are proposed,which provide the decision basis for the government departments to make reasonable vaccine production and vaccination plan.

关键词： Capacity constraints free treatment heuristic algorithm integer programming multistage vaccine production and allocation

Robust multi-objective optimization of rolling schedule for tandem cold rolling based on evolutionary direction differential evolution algorithm

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Journal of Iron and Steel Research(International) 2017年第8期24卷 795-802页

作者： yong li Lei fang School of Electrical Engineering Shenyang University of TechnologyShenyang 110873LiaoningChina School of Information Science and Engineering Shenyang University of TechnologyShenyang 110873LiaoningChina

According to the actual requirements,profile and rolling energy consumption are selected as objective functions of rolling schedule optimization for tandem cold rolling.Because of mechanical wear,roll diameter has some uncertainty during the rolling process,ignoring which will cause poor robustness of rolling schedule.In order to solve this problem,a robust multi-objective optimization model of rolling schedule for tandem cold rolling was established.A differential evolution algorithm based on the evolutionary direction was proposed.The algorithm calculated the horizontal angle of the vector,which was used to choose mutation vector.The chosen vector contained converging direction and it changed the random mutation operation in differential evolution algorithm.Efficiency of the proposed algorithm was verified by two benchmarks.Meanwhile,in order to ensure that delivery thicknesses have descending order like actual rolling schedule during evolution,a modified Latin Hypercube Sampling process was proposed.Finally,the proposed algorithm was applied to the model above.Results showed that profile was improved and rolling energy consumption was reduced compared with the actual rolling schedule.Meanwhile,robustness of solutions was ensured.

关键词： Robust multi-objective optimization Rolling schedule Evolutionary direction Horizontal angle Mutation vector

Facile and Cost-Efficient Synthesis of Photovoltaic Polymers via Direct Arylation Coupling

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Chinese Journal of Polymer Science 2023年第11期41卷 1663-1685,I0004页

作者： Xiao-Chen Wang Yuan Zhang Jia-Xin Yang Jin-Jun Shao Ming-Feng Wang Yong-Fang Li School of Materials Science and Engineering Shaanxi Normal UniversityXi'an 710119China Key Laboratory of Flexible Electronics(KLOFE)&Institute of Advanced Materials(IAM) School of Flexible Electronics(Future Technologies)Nanjing Tech UniversityNanjing 211816China School of Science and Engineering The Chinese University of Hong KongShenzhen 518172China Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Organic SolidsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China

As the high calibre candidate of lightweight and flexible solar cells,polymer solar cells(PSCs)have made tremendous progress in recent years.However,the active photovoltaic materials in PSCs are mainly synthesized by metal-mediated coupling reaction requiring harsh reaction conditions,multiple-step synthesis,and cumbersome purification,which is not cost-efficient and may bring toxicity concerns.It is not favorable to the production of photovoltaic polymers and PSC devices on a large scale,and therefore unsuitable for the PSCs industrialization.Direct arylation coupling reaction via aromatic C―H bonds activation enables the synthesis of conjugated polymers under mild conditions and simultaneously reduces synthetic steps,difficulty,and toxic reaction byproducts.This review provides an overview of the history of preparing representative photovoltaic polymers utilized in PSCs through direct arylation reactions and discusses the activity and selectivity of C―H bonds in typical building blocks under different reaction conditions.Especially,the impact of direct arylation condition on defect formation and photovoltaic performance of the photovoltaic polymers is addressed and compared with conventional Stille coupling methods.

关键词： Photovoltaic polymers Direct arylation coupling C―H bonds activation Polymer solar cells(PSCs) Organic solar cells(OSCs) Low-cost

Hepatic perivascular epithelioid cell tumor:A case report

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World Journal of Clinical Cases 2022年第13期10卷 4273-4279页

作者： Yong-Fang Li liang Wang Yi-Jing Xie Department of Hepatology Lanzhou University The Second HospitalLanzhou 730030Gansu ProvinceChina Department of Radiology Lanzhou University The Second HospitalLanzhou 730030Gansu ProvinceChina

BACKGROUND Perivascular epithelioid cell tumor(PEComa)is a mesenchymal tumor with histologic and immunophenotypic characteristics of perivascular epithelioid cells,has a low incidence,and can involve multiple organs.PEComa originating in the liver is extremely rare,with most cases being benign,and only a few cases are malignant.Good outcomes are achieved with radical surgical resection,but there is no effective treatment for some large tumors and specific locations that are contraindicated for surgery.CASE SUMMARY A 32-year-old woman was admitted to our hospital with a palpable abdominal mass and progressive deterioration since the previous month.An ultrasoundguided percutaneous liver aspiration biopsy was performed.Postoperative pathological immunohistochemical staining was HMB45,Melan-A,and smooth muscle actin positive.Perivascular epithelioid tumor was diagnosed.The tumor was large and could not be completely resected by surgery.Further digital subtraction angiography revealed a rich tumor blood supply,and interventional embolization followed by surgery was recommended.Finally,the patient underwent transarterial embolization(TAE)combined with sorafenib for four cycles.Angiography reexamination indicated no clear vascular staining of the tumor,and the tumor had shrunk.The patient was followed up for a short period of time,achieved a stable condition,and surgery was recommended.CONCLUSION Adjuvant combination treatment with TAE and sorafenib is safe and feasible as it shrinks the tumor preoperatively and facilitates surgery.

关键词： Perivascular epithelioid cell tumor liver Treatment Transarterial embolization Sorafenib Case report

lightweight fault localization combined with fault context to improve fault absolute rank

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Science China(Information Sciences) 2017年第9期60卷 178-193页

作者： yong WANG Zhiqiu HUANG yong li Bingwu fang College of Computer Science and Technology Nanjing University of Aeronautics and Astronautics College of Computer and Information Anhui Polytechnic University

lightweight fault localization(LFL), which outputs a list of suspicious program entities in descending order based on their likelihood to be a root fault, is a popular method used by programmers to assist them in debugging. However, owing to the nature of program structures, it is impossible for LFL to always rank the root faulty program entity at the top of a ranking list. Recently, Xia et al. noted in their study that programmers inspect the first top-K-ranked program entities outputted by an LFL tool in sequence. Therefore,it is of practical significance to further improve the absolute rank of those buggy programs by using LFL if the root fault is ranked higher. To solve this issue, we propose a new LFL combined with a fault context to improve the fault absolute rank. We conduct experiments in which we apply our proposed approach to seven Siemens benchmark programs. The results show that by combining the suspiciousness scores of program entities with their fault-context suspiciousness scores that are based on an LFL called Dstar, our approach can improve the fault absolute rank with an effectiveness rate of 35.7% for 129 faulty versions from the seven benchmark programs. It should be noted that our approach can obtain an average improvement of 65.18% for those improved programs to which LFL can be effectively applied, and that there were improvements to seven top-ranked root faults of buggy programs.

关键词： fault context fault localization program spectrum absolute rank debugging

Influential factors of spatial performance in metro-led urban underground public space:A case study in Shanghai

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Underground Space 2023年第1期8卷 229-251页

作者： Chen-Xiao Ma fang-Le Peng yong-Kang Qiao Hu li Research Center for Underground Space&Department of Geotechnical Engineering Tongji UniversityShanghai 200092PR China Ji’nan Rail Transit Group Co. Ltd.Ji’nan 250014Shandong ProvincePR China

Spatial performance measures the space usage of each underground segment in metro-led urban underground public space(UUPS).It usually varies in different UUPS segments and at different periods.Many environmental factors and space attractors can influence spatial performance in UUPS including spatial configurations,transportation facilities,space design characteristics,and commercial and work-ing facilities.This study intends to figure out the temporal and spatial distribution patterns of spatial performance in UUPS and then reveal the main influential factors and their impact mechanisms.The UUPS in Jiangwan–Wujiaochang Sub-center was selected as the study case.Cordon counting methods and multiple regression models were employed to collect the pedestrian data and quantitatively analyze the correlations between pedestrian flows and candidate influential factors.The study verified that spatial configurations were the most important factors instead of underground or surface attractors.There existed an interactive effect among pedestrian move-ments,spatial configurations,and commerce distribution in metro-led UUPS.Walkway width and the distribution of metro stations could partly affect spatial performance.The influential mechanisms of metro stations were different on weekdays and at weekends.Underground segments belonging to shopping malls in UUPS had a negative impact on spatial performance only on weekdays.Results of this study can provide insights for more efficient layout planning and design of metro-led UUPS in Chinese metropolitan cities.

关键词： Urban underground public space Metro-led area Spatial performance Cordon count Multiple regression method

Thirty-day outcomes of in-hospital multi-vessel versus culpritonly revascularization strategy for ST-segment elevation myocardial infarction with multivessel coronary disease

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Journal of Geriatric Cardiology 2023年第7期20卷 485-494页

作者： Yu-Xi li Bei-Ning WANG fang-fang FAN Yan ZHANG Jie JIANG Jian-Ping li Ya-ling HAN yong Huo CCC investigators Department of Cardiology Peking University First HospitalBeijingChina Cardiovascular Research Institute and Department of Cardiology General Hospital of Northern Theater CommandShenyangLiaoningChina 不详

BACKGROUND Many studies have demonstrated the benefit of complete multivessel revascularization versus culprit-only intervention in patients of ST-segment elevation myocardial infarction(STEMI)and multivessel coronary artery disease.However,only a few single-center retrospective studies were performed on small Chinese cohorts.Our study aims to demonstrate the advantage of multivessel percutaneous intervention(PCI)strategy on 30-day in-hospital outcomes to patients with STEMI and multivessel disease in larger Chinese population.METHODS From the Improving Care for Cardiovascular Disease in China-Acute Coronary Syndrome(CCC-ACS)project,5935 patients with STEMI and multivessel disease undergoing PCI and hospitalized for fewer than 30 days were analyzed.After 5:1 propensity score matching,3577 patients with culprit-only PCI and 877 with in-hospital multivessel PCI were included.The primary outcome was major adverse cardiovascular and cerebrovascular event(MACCE),defined as a composite of myocardial infarction,all-cause death,stent thrombosis,heart failure,and stroke.RESULTS Multivariable logistic regression analysis revealed that in-hospital multivessel PCI was associated with lower risk of 30-day MACCE(adjusted OR=0.75,95%CI:0.57-0.98,P=0.032)than culprit-only PCI and conferred no increased risk of allcause death,myocardial infarction,stent thrombosis,stroke,or bleeding.Subgroup analysis showed that MACCE reduction was observed more often from patients with trans-femoral access(OR=0.34,95%CI:0.15-0.74)than with trans-radial access(OR=0.87,95%CI:0.66-1.16,P for interaction=0.017).CONCLUSIONS The in-hospital multivessel PCI strategy was associated with a lower risk of 30-day MACCE than culprit-only PCI in patients with STEMI and multivessel coronary artery disease.

关键词： infarction coronary myocardial

Associations of Occupational Stress and Coping Styles with Well-Being Among Couriers-Three Cities,Zhejiang Province,China,2021

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China CDC weekly 2023年第20期5卷 446-451,I0002页

作者： Panqi Xue Yixin Zhang fang Wei lifang Zhou Xinglin fang yong Hu Yu Hong Shuang li Xiaoming Lou Hua Zou Institute of Occupational Health and Radiation Protection Zhejiang Provincial Center for Disease Control and PreventionHangzhou CityZhejiang ProvinceChina Department of Public Health Hangzhou Normal UniversityHangzhou CityZhejiang ProvinceChina National Institute of Occupational Health and Poison Control Chinese Center for Disease Control and PreventionBeijingChina

Summary What is already known about this topic?Prior research has primarily concentrated on occupational health concerns,including injuries and heatstroke,among couriers.Nevertheless,there has been a scarcity of emphasis on mental health aspects,with existing studies predominantly addressing the risk factors associated with occupational stress.What is added by this report?The present study demonstrated a significant association between occupational stress and well-being among couriers,with positive coping strategies acting as a mediating factor.Furthermore,the results indicate that implementing a positive coping style may mitigate the impact of occupational stress on well-being.What are the implications for public health practice?Future public policy initiatives should focus on promoting the well-being of couriers by fostering improvements in the workplace environment,reevaluating the organization of work,and delivering support to couriers in managing occupational stress.

关键词： injuries policy primarily

Integration of filter membrane and Ca_(2)Nb_(3)O_(10) nanosheets for high performance flexible UV photodetectors

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Journal of Materials Science & Technology 2022年第34期129卷 108-114页

作者： yong Zhang Fa Cao Siyuan li Xinya liu lixing Kang limin Wu Xiaosheng fang School of Electronic and Information Engineering Changshu Institute of TechnologyChangshu 215500China Department of Materials Science Fudan UniversityShanghai 200433China Division of Advanced Materials Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of SciencesSuzhou 215123China College of Chemistry and Chemical Engineering Inner Mongolia UniversityHohhot 010021China

We report that the integration of filter membrane and Ca_(2)Nb_(3)O_(10)nanosheets(FM@CNO) UV photodetector(UV PD) shows high performance and excellent flexibility. The Ca_(2)Nb_(3)O_(10)nanosheets were prepared by a facile solid-state reaction and liquid exfoliation process. The Ca_(2)Nb_(3)O_(10)nanosheets can be integrated into the pores of a filter membrane via a simple vacuum filtration method. The FM@CNO UV PD shows high performance under 300 nm light illumination at 5 V bias, including high responsivity(0.08 AW^(-1)), high detectivity(1.1 × 10^(12)Jones), high UV/visible rejection ratio(3.86 × 10^(3)) and fast speed(0.12/1.24 ms). Furthermore, the FM@CNO device exhibits excellent flexibility after many bending cycles.In addition, the FM@CNO array device was used as a pixel array detector for UV imaging. This work provides a novel approach to achieve high performance flexible PDs based on filter membrane and two dimensional materials.

关键词： UV photodetector Ca_(2)Nb_(3)O_(10)nanosheets Filter membrane Flexible