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531.
The classic perishable inventory problem assumes that the retailer should not be affected by upstream suppliers in the ordering process. However, real-world operation and management entail a relationship of competition and cooperation between retailers and suppliers. Suppliers therefore influence retailers′ decision-making processes. Suppliers often use discount marketing, which is effective in attracting retailers and increasing the sales volume of products. This also allows retailers to order products at lower cost, creating a win-win scenario. Value discounts and quantity discounts are commonly used in discount marketing. Value discounts allow a retailer to enjoy a cash discount when the retailer′s total order value reaches a certain value, and quantity discounts refer to a price discount offered by the supplier for all products when the retailer′s single order quantity exceeds a fixed value. Most studies in the literature on inventory management assume that the demand or demand distribution is known;however, in reality, it is difficult to obtain accurate demand and demand distribution. Historical demand data are usually the only information that is available. Developments in theoretical computer science allow online learning algorithms to completely depart from the assumption of statistical information and rely only on historical data for decision-making. The Weak Aggregating Algorithm (WAA), an online learning algorithm, constructs online strategy by learning from different experts′ advice and aggregating it;the online strategy can thus track the best expert advice. This assists online decision makers in effectively integrating various types of information and making decisions on such information. This study expands the research on the single-product, multi-period perishable inventory problem in the context of value discounts and quantity discounts without any assumption of statistical information. This article applies the WAA to learning from different experts′ advice in studying the perishable inventory problem when value discounts and quantity discounts can be used. The online ordering strategies (probability-free solutions) are constructed as follows. First, at the beginning of every period, experts recommend their static advice for the specific perishable inventory decision problem;such expert advice is fixed and will not be changed throughout all periods. Second, in the case of value discounts or quantity discounts, the online decision maker applies the WAA to assign different degrees of trust to different experts′ advice and then integrates the advice to make a decision. Last, the actual decision result of the decision problem is obtained, and cumulative gains are computed to evaluate the performance of the experts and the online decision maker. This paper constructs online ordering strategies in different situations. For real-valued order quantities, we aggregate experts′ advice to propose an online order strategy that considers value discounts in detail. We analyze a more practical case in which the order quantity is an arbitrary integer by constructing an online ordering strategy under value discounts through learning from expert advice. We then approach the matter from continuous and discrete angles to propose two explicit online order strategies under quantity discounts. This paper further verifies the performance of the proposed online ordering strategies through theoretical analysis and the use of numerical examples. Competitive performance is measured as the difference between the cumulative gains from using the online ordering strategies and the cumulative gains from following the best expert advice. The theoretical results show that the cumulative gains of the given online ordering strategies are as large as those of the best expert advice and that they outperform their benchmark strategies. The numerical examples indicate that the cumulative gains achieved by the given online ordering strategies fluctuate slightly around those achieved by the optimal expert advice. The competitive performance of the discrete online ordering strategies outperforms that of the continuous online ordering strategies. The theoretical results are therefore effectively validated. The numerical examples also show that different initial probability distributions have little impact on strategies′ competitive performance. In the case of value discounts, the online ordering strategy has better competitive performance for perishable products with a higher unit price, a lower unit cost, and higher value discounts. Regarding quantity discounts, the online ordering strategy performs better when the perishable products have a higher unit price, a lower unit cost, lower quantity discounts, and a lower discount threshold. A consideration of the actual situation leads to explicit ordering rules being proposed in this paper. These enable retailers to make ordering decisions quickly and effectively without information on future demand and thus to meet market demand with the optimal order quantity and maximize their profits. This paper thus provides guidance for perishable goods inventory management. © 2021. Journal of Industrial Engineering and Engineering Management. All rights reserved.  相似文献   
532.
政府利益的非公共性倾向的特征主要在于:合理性、非主流性、隐匿性、膨胀性。政府利益非公共性倾向的回应及其矫正路径:满足政府的自身正当利益;抑制政府利益非公共性倾向中.不正当的部分。  相似文献   
533.
由于工程项目具有投资大、社会效益广、工期长等特点,要保证项目建设的顺利实施,控制造价就成了关键因素之一。为了有效地对建筑工程造价进行管理,就要对建设项目进行全过程的动态控制。从业主的角度出发,对全过程造价管理存在的主要问题进行分析,并提出了相应的解决对策。  相似文献   
534.
高校自主招生是一种尚未完善的新型人才选拔方式,经过8年的实践,仍然存在招生自主权不足、自主招生的公平和诚信、自主招生测试的科学性、自主招生成本和效率等方面的问题,必须采取有针对性的措施解决这些问题,促进自主招生的进一步发展和完善。  相似文献   
535.
医患关系是医生和患者之间发生的最基本的人际关系,和谐医患关系是构建社会主义和谐社会的重要组成部分。医院暴力是医患关系走向极端的表现,它的存在不仅会威胁医护人员的人身安全和医疗机构的财产安全,而且会影响医院的医疗秩序。从真实案例分析入手,研究医院暴力的概念、特征、成因及对策,具有一定的现实意义。  相似文献   
536.
当前我国房地产行业税收政策中存在着经营环节税负分布不合理、税种交叉重叠、预收帐款纳税时间的确认及会计处理不当等问题,对于这些问题,必须采取切实有效的政策措施加以解决。具体设想是,重新调整开发、保有和转让环节的税负水平,调整与房地产行业相关的各种税种,调整帐款纳税时间,统一会计处理方法等。  相似文献   
537.
Simple iterative and exact solutions are described depending on symmetric percentage points for the Johnson translation system of distributions. A condition is given for a zero skewness parameter.  相似文献   
538.
高校现行教师评价工作中的弊端及对策   总被引:13,自引:0,他引:13  
由于观念和操作上的偏差,高校现行教师评价工作中存在诸多弊端。本文针对现存的弊端,提出相应的思路和策略,为陷入困境中的高校教师评价提供一些借鉴  相似文献   
539.
随着助学贷款政策的推广实施,毕业生借贷不能按时归还的问题也逐渐显露出来.国家助学贷款能否按时收回成为我们不得不思考的一个问题.在这种情况之下,诚信教育和信用档案的建设和完善就成为了现实的要求,可以说,高校信用档案建立与完善具有一定的现实性和必要性,需要社会各界的积极合作与支持.  相似文献   
540.
This paper is concerned with asymptotic properties on the accuracy of numerical solutions. It is shown that the approximation error of the policy function is of the same order of magnitude as the size of the Euler equation residuals. Moreover, for bounding this approximation error the most relevant parameters are the discount factor and the curvature of the return function. These findings provide theoretical foundations for the construction of tests to assess the performance of alternative computational methods.  相似文献   
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