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Potato farmers’ preference for agricultural insurance in China: An investigation using the choice experimental method 被引量:5
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作者 HUANG Ze-ying Alec ZUO +1 位作者 SUN Jun-mao GUO Yan-zhi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第4期1137-1148,共12页
Potato insurance plays an important role in transferring agricultural risks to promote the potato staple strategy. Understanding farmers’ real preferences for potato insurance attributes is important to improve the p... Potato insurance plays an important role in transferring agricultural risks to promote the potato staple strategy. Understanding farmers’ real preferences for potato insurance attributes is important to improve the potato insurance. In this study, a choice experiment was designed with attributes such as peril, minimum compensation ratio for production loss, types of crops covered by insurance, annual premium per mu after subsidy, and complexity of claims procedures. We constructed a mixed logit model based on a questionnaire survey of 362 potato farmers’ choices of insurance attributes from 24 villages in Dingxi City of Gansu Province using random sampling. The results show that:(1) farmers prefer agricultural insurance with widely perils including output price drop and input cost risk;(2) farmers who have suffered plant disease and insect and pest damage are willing to pay a high premium for the insurance with a high compensation ratio and several types of crops covered;full-time farmers and large-scale farmers preferred insurance products with low complexity of claims procedures. Therefore, new potato insurance design could be considered specifically for different farmer groups such as those who had previous disaster experiences, and large-or small-scale farm operations. 展开更多
关键词 agricultural INSURANCE choice experimental method POTATO attributes PREFERENCES
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Choice of operative method for pancreaticojejunostomy and a multivariable study of pancreatic leakage in pancreaticoduodenectomy 被引量:1
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作者 Hui Liang Jian-Guo Wu +4 位作者 Fei Wang Bo-Xuan Chen Shi-Tian Zou Cong Wang Shuai-Wu Luo 《World Journal of Gastrointestinal Surgery》 SCIE 2021年第11期1405-1413,共9页
BACKGROUND As one of the major abdominal operations,pancreaticoduodenectomy(PD)involves many organs.The operation is complex,and the scope of the operation is large,which can cause significant trauma in patients.The o... BACKGROUND As one of the major abdominal operations,pancreaticoduodenectomy(PD)involves many organs.The operation is complex,and the scope of the operation is large,which can cause significant trauma in patients.The operation has a high rate of complications.Pancreatic leakage is the main complication after PD.When pancreatic leakage occurs after PD,it can often lead to abdominal bleeding and infection,threatening the lives of patients.One study found that pancreatic leakage was affected by many factors including the choice of pancreaticojejunostomy method which can be well controlled.AIM To investigate the choice of operative methods for pancreaticojejunostomy and to conduct a multivariate study of pancreatic leakage in PD.METHODS A total of 420 patients undergoing PD in our hospital from January 2014 to March 2019 were enrolled and divided into group A(n=198)and group B(n=222)according to the pancreatointestinal anastomosis method adopted during the operation.Duct-to-mucosa pancreatojejunostomy was performed in group A and bundled pancreaticojejunostomy was performed in group B.The operation time,intraoperative blood loss,and pancreatic leakage of the two groups were assessed.The occurrence of pancreatic leakage after the operation in different patients was analyzed.RESULTS The differences in operative time and intraoperative bleeding between groups A and B were not significant(P>0.05).In group A,the time of pancreatojejunostomy was 26.03±4.40 min and pancreatic duct diameter was 3.90±1.10 mm.These measurements were significantly higher than those in group B(P<0.05).The differences in the occurrence of pancreatic leakage,abdominal infection,abdominal hemorrhage and gastric retention between group A and group B were not significant(P>0.05).The rates of pancreatic leakage in patients with preoperative albumin<30 g/L,preoperative jaundice time≥8 wk,and pancreatic duct diameter<3 mm,were 23.33%,33.96%,and 19.01%,respectively.These were significantly higher than those in patients with preoperative albumin≥30 g/L,preoperative jaundice time<8 wk,and pancreatic duct diameter≥3 cm(P<0.05).Logistic regression analysis showed that preoperative albumin<30 g/L,preoperative jaundice time≥8 wk,and pancreatic duct diameter<3 mm were risk factors for pancreatic leakage after PD(odds ratio=2.038,2.416 and 2.670,P<0.05).CONCLUSION The pancreatointestinal anastomosis method during PD has no significant effect on the occurrence of pancreatic leakage.The main risk factors for pancreatic leakage include preoperative albumin,preoperative jaundice time,and pancreatic duct diameter. 展开更多
关键词 PANCREATODUODENECTOMY Pancreatojejunostomy choice of operative methods Pancreatic leakage Multivariate analysis
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Terminal fertility control: Clients’ own reason for the choice of the contraceptive method
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作者 Daniel Adebode Adekanle Adeola Folashade Afolabi Adewale Samson Adeyemi 《Open Journal of Obstetrics and Gynecology》 2013年第9期706-709,共4页
Background: The prevalence of contraceptive use has increased worldwide due to the development and introduction of modern contraceptives and the establishment of organized family planning programs. In Nigeria, there i... Background: The prevalence of contraceptive use has increased worldwide due to the development and introduction of modern contraceptives and the establishment of organized family planning programs. In Nigeria, there is a very slow rise in contraceptive use prevalence, resulting in high fertility rate. Generally contraceptive is either used for birth spacing, or for the purpose of terminal fertility control to limit the number of children, and the choice of method for this purpose varies. Aims and Objectives: To determine the contraceptive methods of choice among clients seeking terminal fertility control, and their reasons for the choice of such methods. Materials and Methods: A cross-sectional study of clients attending the family planning clinic of Ladoke Akintola University of Technology Teaching hospital over a period of twenty-four months, between July, 2009 and June, 2011. All clients who had completed their family, and wanted a contraceptive method to limit their family size filled the semi-structured questionnaire after giving their informed consent. Clients’ own reasons for the choice of the particular contraceptive method were grouped, entered into SPSS work sheet, and analyzed using SPSS version 17. Result: There were five hundred and ninety-two new contraceptive method acceptors during the study period, of which 264 (44.6%) were for terminal fertility control. Progestogen-only injectable contraceptive was the method of choice for terminal fertility control by 145 (54.9%) of the clients, while 85 (32.2%) made intrauterine contraceptive device (copper-T) their method of choice, and the least chosen method was female surgical sterilization (2, 0.8%). Ease of administration, satisfaction with previous use, long duration of action, and husband’s preference were the reasons for the choice of the methods. Conclusion: There is awareness of terminal fertility control in Nigeria, especially in the southwestern region of the country, and this may be responsible for the decreasing prevalence of grandmultiparity in the region. However, reversible contraceptive method is the preferred option for this purpose. 展开更多
关键词 TERMINAL Fertility Control method choice REASONS
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The Path Choice and Method of Chinese Rural Governance Ethics Research
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作者 Ang Liu 《Journal of Sociology Study》 2019年第4期169-176,共8页
The 19th National Congress of the Communist Party of China put forward the strategy of Rural Revitalization.Effective governance is the key to rural revitalization.Effective rural governance needs to properly deal wit... The 19th National Congress of the Communist Party of China put forward the strategy of Rural Revitalization.Effective governance is the key to rural revitalization.Effective rural governance needs to properly deal with the ethical relationship in the process of governance.The study of rural governance ethics in China includes three kinds of path choices.They are paradigm shift from top-down to bottom-up,organic integration of special and general,and interweaving between tradition and modernity.The paradigm shift from top-down to bottom-up needs to be done by methods,such as the use of the relationship between theory and practice,the change from abstract research to applied research,and the implementation of fieldwork surveys.Special and general organic integration depends on methods,such as the law of contradiction specificity and universality,the cooperation of induction and deduction,the operation of case studies,etc.The interweaving of tradition and modernity requires methods to be realized,such as the negation of negation,moral narrative,and non-intrusive research. 展开更多
关键词 RURAL GOVERNANCE ETHICS path choice method
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Methods for Industrial Measurement and Basic Principles of Their Choices
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作者 FENG Wenhao 《Geo-Spatial Information Science》 2002年第2期28-36,共9页
In this paper,a variety of industrial objects are systematically analyzed.Ten methods for industrial measurement are summarized.For each method,its nature,advantages,disadvantages and adaptability are briefly given.Th... In this paper,a variety of industrial objects are systematically analyzed.Ten methods for industrial measurement are summarized.For each method,its nature,advantages,disadvantages and adaptability are briefly given.The basic principles to choose the right industrial method are indicated. 展开更多
关键词 系统分析 工业测量法 选择测法原则 GPS法
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A Study on the Determinants of Location Choice in Inward Foreign Direct Investment (FDI): Focusing on the Incheon Free Economic Zone
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作者 TaeUg Rho NanJoo (Nancy) Park 《Journal of Modern Accounting and Auditing》 2012年第4期488-502,共15页
关键词 外国直接投资 区位选择 经济区 FDI 自由 外商直接投资 投资规模 经济全球化
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离散选择实验在卫生人力资源领域的应用进展
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作者 包美玲 黄存瑞 王皓翔 《中国全科医学》 CAS 北大核心 2024年第25期3184-3191,共8页
背景运用离散选择实验(DCE)对卫生人员工作选择倾向性进行研究,可以为制定农村及偏远地区吸引和留用卫生人员相关政策提供科学且有效的依据。目的对DCE应用于卫生人力资源领域的研究进行梳理、总结和归纳,以期为将来的相关研究提供参考... 背景运用离散选择实验(DCE)对卫生人员工作选择倾向性进行研究,可以为制定农村及偏远地区吸引和留用卫生人员相关政策提供科学且有效的依据。目的对DCE应用于卫生人力资源领域的研究进行梳理、总结和归纳,以期为将来的相关研究提供参考。方法于2022年2—4月,系统检索Web of Science、PubMed、中国知网、万方数据知识服务平台、维普网中与DCE应用于卫生人力资源领域相关的文献。提取纳入文献的研究对象、分析模型、选择项设置及研究结果等。结果最终纳入44篇文献,文献发表时间为2000—2020年。研究对象主要为在职卫生工作者、学生;纳入文献中,6篇是标签式,其余为一般式;属性数量为4~8个;水平数量以2~4个居多(88.6%,39/44)。高收入国家的研究中将全科医生团队合作、工作量作为工作属性;中低收入国家的研究中工作属性选择最多的是住房(21次),其次是设施、药物等的配备(19次)、学习/培训机会(16次)。各文献的工作属性均纳入了收入(工资)。形成的工作属性框架包含4个层面:社会层面,包括医院规模、社会支持/尊重、身份确认(编制或成为永久员工);工作层面,包括工作地点、工作条件、工作量、工作(管理)氛围、团队合作、上级指导(针对基层卫生工作者);职业发展层面,包括晋升年限、培训(继续教育)机会、学术和研究机会;生活层面,包括收入、住房、交通、子女教育。分析模型运用最多的是Mixed Logit Model(19次),其次是Conditional Logit Model(9次)、Generalized Multinomial Logit Model(3次)。结论该领域研究结果的异质性较大,难以得出统一结论。而且DCE在卫生人力资源领域的应用仍需进一步在全球范围内推广,相关研究十分有限,得到的证据尚需进一步研究的证实。 展开更多
关键词 离散选择实验 卫生人力 卫生人员 职业选择 研究方法
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选择实验视角下塑料污染治理的农业生态价值评估——来自黑、豫、浙、粤、川五省的经验证据
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作者 韩灵梅 游健强 +1 位作者 申洪涛 邱建华 《生态经济》 北大核心 2024年第8期201-207,共7页
塑料为农业生产带来了极大的便利,但其废弃物的不当管理也造成了严重的环境问题。为了科学评估塑料污染治理的农业生态价值,合理确定污染治理措施的优先序,优化塑料污染治理投入资源配置,论文设计了一个包括源头减量、回收利用、清理整... 塑料为农业生产带来了极大的便利,但其废弃物的不当管理也造成了严重的环境问题。为了科学评估塑料污染治理的农业生态价值,合理确定污染治理措施的优先序,优化塑料污染治理投入资源配置,论文设计了一个包括源头减量、回收利用、清理整治与价格等属性的选择实验,以黑、豫、浙、粤、川5省487份调研数据为例,利用条件Logit模型测算塑料污染治理的边际支付意愿与塑料污染治理价值的补偿剩余。研究表明:(1)受访农业居民在塑料污染治理特征属性上的偏好为:源头减量>清理整治>回收利用,其支付意愿分别为:32.79元/人、25.27元/人、15.78元/人;(2)通过补偿剩余测算,为解决塑料污染治理难题,受访农业居民污染治理支付意愿为147.68元/人。应逐步构建起“减量化—再利用—资源化”的塑料污染全生命周期治理体系,优先考虑源头减量和清理整治方面的治理措施。 展开更多
关键词 选择实验法 塑料污染治理 支付意愿 价值评估
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西南欠发达地区社区医疗服务建设对慢性病患者就医选择的影响
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作者 张雪 戴璟 +3 位作者 许楠楠 杨志丽 张子怡 李伟 《中国卫生事业管理》 北大核心 2024年第2期136-141,共6页
目的:分析西南欠发达地区社区医疗服务建设内容对慢性病患者就医选择的影响,并探讨社区医疗服务各项建设内容的边际影响和贡献程度。方法:在西南欠发达地区采取分层整群随机的抽样方法抽取20个社区(村)1205名慢性病患者进行问卷调查,采... 目的:分析西南欠发达地区社区医疗服务建设内容对慢性病患者就医选择的影响,并探讨社区医疗服务各项建设内容的边际影响和贡献程度。方法:在西南欠发达地区采取分层整群随机的抽样方法抽取20个社区(村)1205名慢性病患者进行问卷调查,采用描述性分析、无序多分类Logistic回归和Shapley值分解法进行统计对比和因素分析。结果:1205名调查对象中,776名慢性病居民选择社区医院就诊(64.4%)。Logistic回归结果显示,社区医院的隐私保护(OR=0.789;95%CI:0.543~0.818)、医疗设备(OR=0.736;95%CI:0.599~0.903)、医学检查(OR=0.559;95%CI:0.381~0.680)建设对慢性病居民由省市级医院流向社区医院有积极影响;社区医院的隐私保护(OR=0.806;95%CI:0.629~0.910)、专家坐诊(OR=0.741;95%CI:0.575~0.954)、医疗设备(OR=0.690;95%CI:0.533~0.785)、护理服务(OR=0.630;95%CI:0.443~0.894)、医学检查(OR=0.611;95%CI:0.452~0.792)、服务态度(OR=0.499;95%CI:0.356~0.741)和收费标准(OR=0.499;95%CI:0.385~0.648)建设对慢性病居民由县区级医院流向社区医院有积极影响。Shapley值分析结果显示,社区医院的隐私保护、医学检查、服务态度、诊疗成本和护理服务建设对慢性病居民就医选择的影响贡献率最大,分别为38.91%,12.44%,11.70%,9.84%和7.15%。结论:加强西南欠发达地区社区医疗服务建设对慢性病居民由省市级医院、县区级医院流向社区医院的促进作用明显。当地政府应加大社区医院在医疗设备、医学检查和专家坐诊方面的投入,发挥医保的杠杆作用,降低社区医院收费标准,提升社区医院服务水平,进一步落实分级诊疗政策。 展开更多
关键词 社区医疗服务 慢性病居民 就医选择 西南欠发达地区 SHAPLEY值法
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前景理论和灰色关联法下定制公交出行分担率选择模型
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作者 孙金凯 林晶 《交通科技与经济》 2024年第2期45-50,共6页
为提高公共交通服务水平和定制公交分担率,以定制公交、常规公交、出租车和地铁4种出行方式为对象,考虑乘坐时间、出行费用、便捷性和舒适性4个出行影响因素,基于多项Logit模型构建前景理论和灰色关联相结合的出行选择模型,并以董屿... 为提高公共交通服务水平和定制公交分担率,以定制公交、常规公交、出租车和地铁4种出行方式为对象,考虑乘坐时间、出行费用、便捷性和舒适性4个出行影响因素,基于多项Logit模型构建前景理论和灰色关联相结合的出行选择模型,并以董屿·福建师大地铁站到福州南火车站为例进行研究。结果表明:定制公交、常规公交、出租车和地铁4种出行方式的分担率分别为28.35%、14.63%、23.14%、33.88%,与实际问卷调查的最大误差在5%以内,与运用效用理论计算所得的分担率相比更符合现实情形;定制公交分担率在票价为1元或2元增减时,并没有产生较大变化,而乘坐时间的缩短却使分担率有较大提升。 展开更多
关键词 定制公交 出行选择 前景理论 灰色关联法 多项Logit模型
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高精主轴装配工艺设计与测试
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作者 孙井泉 《机械工程师》 2024年第5期106-109,共4页
主轴单元是数控机床的重要功能部件之一,其装配质量将影响机床的加工精度及稳定性等性能指标。为满足数控机床高精高速的实际需求,降低机床主轴单元的故障率,对主轴运转噪声大、轴承温升过高、切削工件表面有振纹等常见故障现象进行研... 主轴单元是数控机床的重要功能部件之一,其装配质量将影响机床的加工精度及稳定性等性能指标。为满足数控机床高精高速的实际需求,降低机床主轴单元的故障率,对主轴运转噪声大、轴承温升过高、切削工件表面有振纹等常见故障现象进行研究。结合上述故障产生的原因,分别对相关装配过程作了梳理和总结,如:影响主轴运转噪声的主轴组件动平衡校核工序;影响轴承温升及切削性能的选择配置主轴轴承等工序。通过对主轴单元的温升测试及抗振性切削测试,从而验证了所述装配工艺的正确性和合理性,具有一定的借鉴价值。 展开更多
关键词 主轴单元 动平衡校核 选配法 热装配 温升测试 切削测试
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A Gradient Descent Method for Estimating the Markov Chain Choice Model
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作者 Lei Fu Dong-Dong Ge 《Journal of the Operations Research Society of China》 EI CSCD 2023年第2期371-381,共11页
In this paper,we propose a gradient descent method to estimate the parameters in a Markov chain choice model.Particularly,we derive closed-form formula for the gradient of the log-likelihood function and show the conv... In this paper,we propose a gradient descent method to estimate the parameters in a Markov chain choice model.Particularly,we derive closed-form formula for the gradient of the log-likelihood function and show the convergence of the algorithm.Numerical experiments verify the efficiency of our approach by comparing with the expectation-maximization algorithm.We show that the similar result can be extended to a more general case that one does not have observation of the no-purchase data. 展开更多
关键词 Markov chain choice model Parameter estimation Gradient descent method
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A UNIFIED TREATMENT OF REGULARIZATION METHODS FOR LINEAR ILL-POSED PROBLEMS
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作者 金其年 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2000年第1期111-120,共10页
By presenting a general framework, some regularization methods for solving linear ill-posed problems are considered in a unified manner. Applications to some specific approaches are illustrated.
关键词 LINEAR ILL posed problems REGULARIZATION methods a POSTERIORI parameter choice.
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The Continuous Analogy of Newton’s Method for Solving a System of Linear Algebraic Equations
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作者 Tugal Zhanlav Ochbadrakh Chuluunbaatar Gantumur Ankhbayar 《Applied Mathematics》 2013年第1期210-216,共7页
We propose a continuous analogy of Newton’s method with inner iteration for solving a system of linear algebraic equations. Implementation of inner iterations is carried out in two ways. The former is to fix the numb... We propose a continuous analogy of Newton’s method with inner iteration for solving a system of linear algebraic equations. Implementation of inner iterations is carried out in two ways. The former is to fix the number of inner iterations in advance. The latter is to use the inexact Newton method for solution of the linear system of equations that arises at each stage of outer iterations. We give some new choices of iteration parameter and of forcing term, that ensure the convergence of iterations. The performance and efficiency of the proposed iteration is illustrated by numerical examples that represent a wide range of typical systems. 展开更多
关键词 CONTINUOUS ANALOGY of Newton’s method SOLVING the System of Linear ALGEBRAIC Equations Convergence choice of ITERATION Parameter
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Procurement Method Selection for Building Maintenance Projects: The Case of Malaysian Public Universities
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作者 Shirley Jin Lin Chua Azlan Shah Ali Anuar Alias 《World Journal of Engineering and Technology》 2014年第3期7-13,共7页
The purpose of this paper is to implement and validate a decision making framework for building maintenance projects. The growing importance of maintenance sector not only in Malaysia but al- so increasingly globalize... The purpose of this paper is to implement and validate a decision making framework for building maintenance projects. The growing importance of maintenance sector not only in Malaysia but al- so increasingly globalized, the difficulty in selecting an appropriate procurement method and lack of research in this area provide an impetus for this research. There were 19 procurement selection criteria identified. In addition, there were 4 types of procurements methods which include outsourcing by specialist term contract, outsourcing by tendered schedule term contract, out- sourcing by repair and maintenance contract and outsourcing by measured term contract identified to be the most popular procurement methods adapted by public universities currently and at the same time were considered most important. The decision making framework was developed based on AHP technique and principles. Expert Choice Software was employed as development tool where the criteria and alternatives were integrated into the framework. Finally, structured interview was conducted to validate the framework developed. The validation process was carried out through structured interview with selected public university. 展开更多
关键词 ANALYTIC HIERARCHY Process EXPERT choice Software Procurement method Building Maintenance Management Public UNIVERSITIES
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乡村振兴背景下采摘型休闲农业消费者选择偏好研究——基于选择实验法的实证分析 被引量:2
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作者 韩振兴 刘东辉 常向阳 《农林经济管理学报》 北大核心 2023年第3期322-329,共8页
基于江苏省568个消费者样本,以草莓采摘为例,通过选择实验法采用Mixed Logit模型和潜类别模型,实证分析消费者对草莓园不同属性的偏好、各属性的相对重要性及支付意愿和偏好异质性来源等问题。结果表明:消费者对口碑好、有品牌的草莓园... 基于江苏省568个消费者样本,以草莓采摘为例,通过选择实验法采用Mixed Logit模型和潜类别模型,实证分析消费者对草莓园不同属性的偏好、各属性的相对重要性及支付意愿和偏好异质性来源等问题。结果表明:消费者对口碑好、有品牌的草莓园偏好较强,且更倾向于选择高架栽培和提供农家乐的草莓园;消费者对各属性偏好的支付意愿从大到小依次为口碑、品牌、高架栽培和农家乐;根据异质性来源可以将消费者划分为价格敏感型、农家乐偏好型、口碑导向型、舒适偏好型等4种类型。据此,建议草莓园经营者增加对草莓园口碑和品牌建设的关注,改进草莓园设施建设和采摘定价,明确草莓园市场定位,针对不同类型的消费者采取相应的市场经营策略。 展开更多
关键词 草莓采摘 选择实验法 Mixed Logit模型 潜类别模型 消费者偏好
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南河煤业选煤厂选煤方法的选择
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作者 王鹏 《山西化工》 CAS 2023年第12期97-99,共3页
选煤厂根据自身情况选择合理的选煤方法是非常重要的,目前最常用的煤炭主选方法是重介质分选和跳汰分选。南河选煤厂通过分析自身的原煤煤质,然后选择跳汰分选作为选煤方法,对其他相似选煤厂选择选煤方法有一定的借鉴作用。
关键词 选煤方法 跳汰分选 选择
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黑龙江省国家级农业现代化示范区建设模式与路径选择
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作者 马凤才 何建龙 焦景虎 《农业展望》 2023年第12期59-66,共8页
国家农业现代化示范区作为推进农业现代化发展的重要抓手,探索农业现代化示范区建设模式有助于示范引领同类地区农业农村现代化发展。在归纳示范区建设模式的基础上,从设施农业发展、农业产业集群发展、产业融合发展、农业绿色发展、农... 国家农业现代化示范区作为推进农业现代化发展的重要抓手,探索农业现代化示范区建设模式有助于示范引领同类地区农业农村现代化发展。在归纳示范区建设模式的基础上,从设施农业发展、农业产业集群发展、产业融合发展、农业绿色发展、农业数字发展5个层面构建示范区评价指标体系,并基于黑龙江省示范区数据,利用熵权法和综合指数法测度黑龙江省国家农业现代化示范区综合发展水平,探讨其未来主要建设模式和发展路径。结果表明:(1)黑龙江省国家农业现代化示范区建设模式可分为设施农业带动、产业集群带动、产业融合带动、绿色农业带动、数字农业带动发展型等5种类型;(2)关于各示范区主要建设模式,龙江县为数字农业或产业集群带动发展型,富锦市为设施农业带动发展型,庆安县为产业融合带动发展型,海伦市为农业绿色带动发展型。黑龙江省国家农业现代化示范区拥有较强的发展潜力和空间,应立足发展优势,持续深入推进农业现代化建设。 展开更多
关键词 黑龙江省 农业现代化 示范区 建设模式 熵权法 综合指数法 路径选择
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基于称名反应模型的CD-CAT选题方法比较研究
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作者 张杰 罗照盛 +1 位作者 喻晓锋 秦春影 《心理科学》 CSCD 北大核心 2023年第6期1495-1503,共9页
当前大多数CD-CAT有关的研究都是基于0-1计分的数据资料展开的,而在实际的教育与心理测验中,还包含大量称名反应数据。本文基于称名反应认知诊断模型(NR-cRUM)开发了适用于称名反应数据的CD-CAT(以下简称NCDCAT),并将7种0-1计分CD-CAT... 当前大多数CD-CAT有关的研究都是基于0-1计分的数据资料展开的,而在实际的教育与心理测验中,还包含大量称名反应数据。本文基于称名反应认知诊断模型(NR-cRUM)开发了适用于称名反应数据的CD-CAT(以下简称NCDCAT),并将7种0-1计分CD-CAT的选题方法引入NCD-CAT中。比较不同条件下,不同选题方法对被试判准率和测验效率的影响。结果表明NR_PWCDI、NR_MPWKL等PWKL系新方法和NR_SHE/MI方法能较好地适用于NCD-CAT,且在大多数条件下优于基线方法 NR_PWKL。研究拓展了称名多级计分CD-CAT的选题方法。 展开更多
关键词 CD-CAT 称名反应 NR-cRUM 选题方法 多项选择题
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基于海鸥算法的圆柱度误差评定方法 被引量:1
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作者 吴天昊 赵则祥 +1 位作者 王帅飞 史鑫朝 《机电工程》 CAS 北大核心 2023年第3期422-428,共7页
圆柱体零件的几何精度直接影响到机械设备的总体性能,而圆柱度误差是圆柱体零件的几何误差之一,对圆柱度误差进行精确测量和评估十分重要。针对最小区域圆柱度误差评定能否达到全局最优的问题,提出了一种基于新型元启发式海鸥算法(SOA)... 圆柱体零件的几何精度直接影响到机械设备的总体性能,而圆柱度误差是圆柱体零件的几何误差之一,对圆柱度误差进行精确测量和评估十分重要。针对最小区域圆柱度误差评定能否达到全局最优的问题,提出了一种基于新型元启发式海鸥算法(SOA)的圆柱度误差评定方法。首先,对圆柱体轮廓要素的提取进行了阐述,并建立了基于最小区域法的圆柱度误差评定模型;然后,介绍了海鸥优化算法中海鸥的位置更新原理、算法的优化准则和算法流程;最后,用Talyrond 585LT圆柱度仪提取了6个圆柱零件的轮廓数据,并进行了评定,通过对比不同种群数的优化结果,找到了最佳种群数,同时将其所得结果与采用遗传算法(GA)所得结果进行了对比。研究结果表明:种群数的选择对海鸥算法的优化结果影响较大,在种群数为30时能达到最优解,其精度比遗传算法高,其运行时间随着种群数的增加而增加。海鸥算法优化过程稳定,在评定最小区域圆柱度误差(MZC)方面有较好的适应性。 展开更多
关键词 圆柱度测量仪 海鸥算法 种群数选择 位置更新原理 算法优化准则 最小区域法圆柱度误差 最小区域法
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