What Makes Koreans Happy?: Exploration on the Structure of Happy Life among Korean Adults

The current study explored the perceptions of Korean people about what can make them happy and constructed a comprehensive measurement of happiness of Korean. A total of 61 Korean adults participated in Focused Group Interview (FGI), where they were asked three questions (e.g., What makes you happy? What could make you happier than now? In general, who is a happy person?). Participants’ responses were reviewed by the present investigators independently and 152 statements of happy life with 18 categories were derived from content-analysis. The list of 152 statements of happy life was administered to 517 Korean adults to assess the importance of each item for Koreans’ happy life through the objective rating scale (6-point Likert scale). Confirmatory factor analysis showed that most factors were unidimensional. The items with low reliability were deleted and some new items were added, resulting in the experimental form of the Happy Life Inventory with 156 items and 18 categories including a new category of religion. The preliminary form of the Happy Life Inventory and the Psychological Well-being scale were administered to a nationwide sample of 1503 Korean adults in order to assess their happiness through 6-point Likert scale. The responses from 877 participants were submitted to exploratory factor analysis. The items with low factor loadings were excluded and 98 items with 16 factors were included in the final version of the Happy Life Inventory. Confirmatory factor analysis of the responses from 611 subjects confirmed that the 16 factor model was appropriate and most categories had one underlying dimension with moderate to high reliabilities. Correlations between the Happy Life Inventory and the psychological well-being scale supported construct validity of the Happy Life Inventory. Suggestions for further research were discussed.     

质疑与反思：“重回金本位”和“无海图航海”

金本位制成为束缚经济繁荣稳定的＂紧身衣＂,而在＂无海图航海＂中金融危机事件又接连不断。因此,既不能＂重回金本位＂,又不要继续＂无海图航海＂。为了保证国际货币体系的安全稳定,需要建立平稳运行的汇率制度。创建国际规则约束泛滥成灾的美元,是汇率制度平稳运行的基本前提;实行有管理的浮动汇率制,是国际信用机制运行的主要手段。     

Joint modified block replacement and production/inventory control policy for a failure-prone manufacturing cell

This paper considers a joint preventive maintenance (PM) and production/inventory control policy of an unreliable single machine, mono-product manufacturing cell with stochastic non-negligible corrective and preventive delays. The production/inventory control policy, which is based on the hedging point policy (HPP), consists in building and maintaining a safety stock of finished products in order to respond to demand and to avoid shortages during maintenance actions. Without considering the impact of preventive and corrective actions on the overall performance of the production system, most authors working in the reliability and maintainability domains confirm that the age-based preventive maintenance policy (ARP) outperforms the classical block-replacement policy (BRP). In order to reduce wastage incurred by the classical BRP, we consider a modified block replacement policy (MBRP), which consists in canceling a preventive maintenance action if the time elapsed since the last maintenance action exceeds a specified time threshold. The main objective of this paper is to determine the joint optimal policy that minimizes the overall cost, which is composed of corrective and preventive maintenance costs as well as inventory holding and backlog costs. A simulation model mimicking the dynamic and stochastic behavior of the manufacturing cell, based on more realistic considerations of the real behavior of industrial manufacturing cells, is proposed. Based on simulation results, the joint optimal MBRP/HPP parameters are obtained through a numerical approach that combines design of experiment, analysis of variance and response surface methodologies. The joint optimal MBRP/HPP policy is compared to classical joint ARP/HPP and BRP/HPP optimal policies, and the results show that the proposed MBRP/HPP outperforms the latter. Sensitivity analyses are also carried out in order to confirm the superiority of the proposed MBRP/HPP, and it is observed that for practitioners, the proposed joint MBRP/HPP offers not only cost savings, but is also easy to manage, as compared to the ARP/HPP policy.     

Optimum common cycle for scheduling a single-machine multiproduct system with a budgetary constraint

This paper deals with the single machine multi-product lot size scheduling problem, and has two objectives. The first objective is to minimize the maximum aggregate inventory for the common cycle (CC) scheduling policy. A simple and easy-to-apply rule has been developed which determines the optimal production sequence that achieves this objective. The second objective is to find an optimal common cycle for minimizing the average production and inventory costs per unit time, subject to a given budgetary constraint. A method has been presented that achieves this objective     

Product universality and design for supply chain management

We describe our experience of developing models in which the principles of design for supply chain management (DFCM) have been implemented for new product development at Hewlett-Packard Company (HP). This experience arises from the development of a new product that is scheduled to be released in 1995. A key design decision faced by the product development team was whether to use a universal module or regionally dedicated modules to satisfy global market requirements. We describe a wide range of factors—including manufacturing and logistics costs—that could be used to support the design decision; these factors associated with product and process design contribute to tolal supply chain costs. We review the analytical model used to evaluate the cost and service implications of the two design alternatives. Finally, we discuss qualitative considerations that might influence the eventual decisions as well as the lessons learned from this real world experience.     

考虑顾客退货时在线企业的定价与订货策略

电子商务环境中,顾客退货是非常普遍的现象,是在线零售企业运营决策不可忽视的重要考虑因素． 以此为背景,本文将顾客退货引入到在线零售企业的单周期和多周期定价订货策 略研究中． 在确定性需求问题中给出了解析解,在随机性需求问题中证明了解的存在唯一性并做了相应的数值试验． 试验结果显示: 单周期情况下,退货率与在线零售企业定价正相关,而与订货量和收益负相关; 价格弹性与在线零售企业定价、收益负相关,对订货量的影响通过一个临界值发生相反的变化; 市场随机波动对在线零售企业的决策行为也有很大影响． 多周期情况下,在线零售企业会在初始期采取低价高订货量策略,而在末期采取高价低订货量策略,退货率越高,企业总收益越低． 同时,针对单周期随机性需求问题,借助期望－方差分析法分析了考虑顾客退货时期望收益的波动,得出风险偏好不同的在线零售企业策略选择有很大不同． 无论哪种情况,努力控制顾客退货率都有利于在线零售企业获得高收益．     

需求预测综合模型及其与库存决策的集成研究

准确的预测有助于企业做出有效的决策,包括生产计划、定价和促销决策等,以减少库存、提高客户满意度和企业竞争力． 以快速消费品为研究对象,分析其需求影响因素,建立了时间序列分析与多元回归整合的需求预测综合模型; 将此预测模型引入到库存决策中,构建了基于库存成本最小的需求预测与库存决策集成模型,并借助变邻域搜索算法获得模型的参数值; 最后,选用实际数据,验证了所构建的需求预测综合模型、物流需求预测与库存决策集成模型及其求解方法的有效性．     

Application and evaluation of packaging postponement strategy to boost supply chain responsiveness: a case study

The purpose of this study is to demonstrate how packaging postponement can be effectively leveraged in a dynamically changing diverse retail market where responsiveness is key. The study also guides about the empirical evaluation of how packaging postponement affects the performance in the sanitary pads supply chain by considering operating measures. The focal company belongs to the Indian Fast Moving Consumer Goods sector, hygiene products category. It examines the measures that are critical to a responsive supply chain and presents a comparative analysis of selected measures before and after implementation. The findings illustrate that the packaging postponement not only improves competitive advantage but also significantly contributes to improving product proliferation and supply chain responsiveness. The study provides understanding of drivers and obstacles for packaging postponement strategy with operational insights about ‘how-to’ implement. Most of modelling-based research studies justify the adoption of postponement through savings in inventory only and underplay on other operating measures. While justifying, studies emphasise ‘form’/manufacturing aspects and underestimate the packaging aspects of postponement. This paper addresses these gap areas by systematically highlighting prerequisites and demonstrates the benefits of adopting a packaging strategy to handle variety and responsiveness in an emerging economy.     

Note on inventory models with Weibull distribution deterioration

This article explores the inventory model with a general demand rate function in which both the Weibull distributed deterioration and partial backlogging are considered. The inventory model discussed here is based on the important finding by Wu [Wu, K.S., 2001. An EOQ inventory model for items with Weibull distribution deterioration, ramp type demand rate and partial backlogging. Production Planning and Control, 12, 787–793]. There are four parts in our research. First, we derive the analytical framework of the inventory model for a general demand rate function1 1.?Based on detailed suggestions of Professor Wafik H. Iskander, Email: whiskander@mail.wvu.edu . Second, for the ramp type demand, we improve Wu's model to find the criterion to guarantee the existence and uniqueness of the optimal solution. Third, we develop a new model to compensate for the missing case in Wu's article. Fourth, we combine our results to show that our findings are applicable to the ramp type demand inventory model, so that the optimal solution is independent of the demand function. Finally, some numerical examples and graphs are provided to illustrate our discovery and demonstrate the application of our analytical framework.     

Quantifying the effectiveness of VMI and integrated inventory management in a supply chain with uncertain lead-times and uncertain demands

This article considers the inventory management problem in a supply chain with uncertain replenishment lead-times and uncertain demands. The optimal integrated inventory management (IIM) policy is developed using stochastic dynamic programming theory. The IIM policy is contrasted with two pull-type vendor-managed inventory policies (VMI-1 and VMI-2) and a traditional retailer-managed inventory policy (RMI). Computational results show that in such stochastic supply chains, IIM performs about 23, 15, and 3% better than the optimised RMI, VMI-1 and VMI-2 policies, respectively, while two VMI policies are about 8 and 20% better than the best RMI. The basestock-based VMI-2 is a very good form of VMI. The ANOVA analysis reveals that the replenishment lead-times have the largest effect on the relative performance between IIM and other policies. Numerical examples demonstrated that the IIM policy has good structural properties and can be characterised by a set of switching curves.