An EOQ model with partial delayed payment and partial backordering

In many transactions concerning selling and buying, a specified delay of payment is offered or accepted by the seller. This can be regarded as a kind of discount and has potential consequences for the order size. These kinds of effects are not explicitly incorporated in the classical formulas for economic order quantities (EOQ). In this research we consider an EOQ problem under partial delayed payment. A fraction of the purchasing cost must be paid at the beginning of the period and the remaining amount can be paid later. Shortages are permitted and occur as a combination of backorders and lost sales. The aim of this paper is to determine the order and shortage quantities.     

A routine-based framework implementing workload control to address recurring disturbances

Abstract

This research focuses on responsiveness in high variety manufacturing environments. To achieve it, the article proposes to develop Dynamic Response Capabilities (DRCs) of the manufacturing system defined as the abilities to readjust the planned operating parameters of workload, capacity, and lead time, in the wake of disturbances. To inform their development, built on the Workload Control theory, a routine-based framework is proposed. The framework supports an integrated approach for the implementation of adaptive decision-making routines for workload, capacity, and lead time readjustments at different stages in the order fulfilment process. Findings from two empirical cases show the appropriateness of the framework to develop and utilise DRCs in different settings of disturbances. Results of a simulation study, with one of the case companies, also shows the effectiveness of the framework to drive performance improvements in presence of recurring disturbances leading to demand variability.     

Judicious order acceptance and order release in make-to-order manufacturing systems

This paper explores a two-stage input control system for fixed capacity make-to-order manufacturing systems (with heavy job tardiness penalties), that selectively accepts incoming orders and holds the accepted ones in a pre-shop queue prior to releasing them to the shop floor. Single-stage input control systems that only allow orders to be delayed in a pre-shop queue (i.e. they do not allow some orders to be rejected) have been previously investigated and found to negatively impact overall due-date performance. The hypothesis motivating this research is that judiciously rejecting a subset of incoming orders can prevent the order release queue from being overloaded when a surge of demand occurs. The input control system is evaluated via experiments using a discrete-event simulation model of a fixed capacity manufacturing system. The experiments reported here suggest that holding orders in the pre-shop queue does not improve due date performance, and that judiciously rejecting orders on its own is a viable alternative mechanism of input control that can deliver improved performance.     

Shop floor characteristics influencing the use of advanced planning and scheduling systems

The purpose of this article is to investigate how the manufacturing process, the shop type and the data quality, i.e. the shop floor characteristics, influence the use of advanced planning and scheduling (APS) systems in production activity and control (PAC). The methodology implemented is a multiple case study at three case companies. Each company has different shop floor characteristics, but all use a scheduling module in an APS system, which supports production scheduling. A theoretical framework is developed suggesting how APS system are used in the PAC activities, and which major aspect to consider. The case analysis shows that the scheduling module in APS system, foremost supports sequencing and dispatching. In particular, the shop type is influenced by the decision of how often the APS runs and what freedom is given to the shop floor. The manufacturing process influences how the dispatch list is created. Contrary to the literature presuming that APS systems are most suitable in job shop processes, it is found that the manufacturing process is not a crucial factor when deciding whether APS systems are an appropriate investment. It is found that the level of data quality needed in the APS system depends to a large extent on how the dispatch list is used. For example, is the dispatch list used as a guideline, not a regulation, the need for accurate data in the module is reduced. This article extends the previous literature concerning APS systems by analysing how APS systems influence PAC as a whole and increase the understanding of the challenges of using APS systems in PAC.     

考虑奖惩机制和成本互担的众包物流服务质量最优控制

研究动态视角下服务平台和接包方如何控制众包物流服务质量的问题。引入众包物流服务质量标准,考虑奖惩机制和成本互担契约,构建了众包物流服务质量控制的微分博弈模型,利用庞特里亚金极大值原理求解出双方的最优质量控制水平、利润以及众包物流服务质量和需求随时间变化的最优轨迹。研究表明：服务价格在集中、分散和成本互担三种决策情形的物流服务过程中都保持不变;成本互担契约情形下,通过控制成本互担比例,服务质量、需求和总利润均能达到集中式情形的最优值,而且当奖惩因子满足一定条件时,双方利润相较于分散式情形都能得到改善;奖惩因子和佣金率的提高会增加接包方提升质量控制水平的积极性,但服务平台出于节约成本的目的会降低自身的质量控制水平,而仅依赖接包方较高的质量控制水平提高物流服务质量;当众包物流服务质量标准超过一定值时,奖惩因子的提高会造成服务平台利润的增加,接包方利润的减少。     

Locus of control and saving: The role of saving motives

Using data from a longitudinal survey representative of the Dutch population, we analyze the relationship between saving and locus of control, and we study the underlying mechanisms. Locus of control measures the extent to which individuals perceive their life outcomes to be determined by their own actions, as opposed to external factors. Those who believe to be in control of future outcomes turn out to save more, both at the extensive (decision to save) and intensive margins (amount saved). We investigate the mechanisms behind this relationship. We implement a mediation analysis to examine the role of saving motives, distinguishing between specific and non-specific purposes. The effect of external locus of control is direct, while the effect of internal locus of control is indirect, largely driven by (non-specific) saving motives.     

乌尔逊-贝尔凹陷有利区预测与勘探目标优选

乌尔逊-贝尔凹陷是海拉尔盆地最重要的油气发现区,现已发现5个大的油气聚集带,勘探前景好。油气成藏主控因素研究表明：研究区具有明显的源控、储控和断控成藏特征,油气藏主要分布在距有效烃源岩中心10 km范围内,NEE和NNE走向断层1 km范围内油气富集程度高,粉砂岩和砂砾岩为最有利的储集岩性,扇三角洲前缘亚相为最有利的沉积相。应用控藏要素多元叠合法对该凹陷南屯组二段进行了成藏有利区综合评价,优选出三级有利成藏区,通过分析有利区内断层型圈闭的断层封闭性能,对凹陷南屯组二段圈闭进行了成藏评价,优选出10个有利勘探目标,为凹陷下步勘探指明了方向。     

“人肉搜索 ”的作用、风险及其控制

＂人肉搜索＂这种由人工参与解答,通过机器算法获得结果的搜索机制,在利用现代科技发展过程中逐渐形成了自己的特色。＂人肉搜索＂对社会产生了广泛影响,一方面起到打击违法犯罪,监督政府官员,强化道德压力和为民排忧解难的社会积极作用;另一方面也存在侵犯隐私的隐患和暴力性风险。借助道德的力量和法律的控制手段规约＂人肉搜索＂,可以避免其可能产生的隐患,发挥人肉搜索的积极效应,促进其健康发展。     

国内所有权保留买卖合同中标的物风险移转新论

所有权保留买卖作为现代民法权利分化的一种现象,在买卖双方以及第三人之间是一种独一无二的利益平衡方式。然而,国内所有权保留买卖合同标的物风险的转移没有明确规定,可以按照交易时的环境和条件,由能够控制风险的一方当事人承担标的物转移毁损、灭失的风险,较能实现当事人的利益平衡。     

网络传播自由及其规制

网络传播自由及其规制是网络传播伦理的一个核心问题,本文揭示了网络传播自由的技术和文化背景,阐述了规制网络传播自由所引起的争论,探讨了网络传播自由的规制方式.