A Proposed Feature Selection Particle Swarm Optimization Adaptation for Intelligent Logistics--A Supply Chain Backlog Elimination Framework

The diversity of data sources resulted in seeking effective manipulation and dissemination.The challenge that arises from the increasing dimensionality has a negative effect on the computation performance,efficiency,and stability of computing.One of the most successful optimization algorithms is Particle Swarm Optimization(PSO)which has proved its effectiveness in exploring the highest influencing features in the search space based on its fast convergence and the ability to utilize a small set of parameters in the search task.This research proposes an effective enhancement of PSO that tackles the challenge of randomness search which directly enhances PSO performance.On the other hand,this research proposes a generic intelligent framework for early prediction of orders delay and eliminate orders backlogs which could be considered as an efficient potential solution for raising the supply chain performance.The proposed adapted algorithm has been applied to a supply chain dataset which minimized the features set from twenty-one features to ten significant features.To confirm the proposed algorithm results,the updated data has been examined by eight of the well-known classification algorithms which reached a minimum accuracy percentage equal to 94.3%for random forest and a maximum of 99.0 for Naïve Bayes.Moreover,the proposed algorithm adaptation has been compared with other proposed adaptations of PSO from the literature over different datasets.The proposed PSO adaptation reached a higher accuracy compared with the literature ranging from 97.8 to 99.36 which also proved the advancement of the current research.

Fuzzy Inventory Model under Selling Price Dependent Demand and Variable Deterioration with Fully Backlogged Shortages

The objective is to develop a model considering demand dependent on selling price and deterioration occurs after a certain period of time, which follows two-parameter Weibull distribution. Shortages are allowed and fully backlogged. Fuzzy optimal solution is obtained by considering hexagonal fuzzy numbers and for defuzzification Graded Mean Integration Representation Method. A numerical example is provided for the illustration of crisp and fuzzy, both models. To observe the effect of changes in parameters, sensitivity analysis is carried out.

异地分布式多SCRUM项目产品Backlog分解过程影响因素分析

将异地分布和SCRUM方法相结合,分析产品Backlog分解过程,提出分解过程的几种重要影响因素:优先级设置、团队地理位置、任务稳定性、团队间差异、任务工作量估算。采用问卷调查的方法收集数据,然后用SPSS软件进行数据分析,研究各因素对产品Backlog分解过程的影响。研究结果表明,优先级和任务的稳定性以及工作量估算对产品Backlog分解过程有显著影响,而团队的地理位置和团队差异则没有显著影响。研究结果有助于SCRUM开发团队更好地完成产品Backlog的工作。

高效制定并使用Scrum开发的产品Backlog

Scrum开发过程框架中,产品Backlog是产品所要具备的所有功能的总纲,是Scrum过程的核心。产品Backlog就类似于传统顺序开发模型中的需求分析,但它不需要完全的确定和细化产品的需求,也不用形成完整使用说明,它用的是另一种恰到好处的方式。本文从三个方面讨论如何高效制定并使用产品Backlog,并举一个考务系统的Scrum开发实例进行深入说明,希望可以为刚转型Scrum的传统开发团队提供参考。

Analysis of Stress Backlogs during Case-File Processing in Forensic Science Laboratory

Case-file backlogs were identified as one of the cause factors affecting the competitiveness of the forensic science laboratory (FSL). Backlogs represent case-files?that remain unprocessed or unreported within a selected time interval (year, week or month) which leads to increased customer complaints, rework, cost of analysis, degradation of biological samples, etc. Case-file backlogging was quantified in three consecutive years (2014 to 2016), using the following parameters: case-files received and case-files processed, difference of which gives case-files backlogged. There was a need to define time interval for a case-file to be regarded as backlogged (that is, one week), results of which can translate into backlogged case-files per month or year. A data collection tool was established and used for three work stations (forensic chemistry, biology/DNA and toxicology laboratories). The tool includes starting and ending date for each?time interval, in which the numbers of case-files received and processed were entered followed by computing the backlogs. It was observed that, case-files reported?increased between 2014 and 2016 leading to a decrease in backlogged case-files.?The annual percentage of the case-files backlogged was highest for forensic?toxicology. The highest number of case-files backlogged was observed for forensic?chemistry, followed by forensic biology/DNA. The number of case-files?backlogged per analyst per year was highest in 2014 and dropped continuously?towards 2016, being comparably higher in forensic biology/DNA and chemistry.?Probability density functions (PDFs) and cumulative distribution functions (CDFs)?of backlogs data indicated that a large number of backlogs created in previous?weeks were eliminated. It was concluded that the effect of case-file backlogging on FSL competitiveness can be minimized by continued management effort in backlog elimination.

高效制定并使用Scrum开发的产品Backlog

Scrum开发过程框架中,产品Backlog是产品所要具备的所有功能的总纲,是Scrum过程的核心。产品Backlog就类似于传统顺序开发模型中的需求分析,但它不需要完全的确定和细化产品的需求,也不用形成完整使用说明,它用的是另一种恰到好处的方式。本文从三个方面讨论如何高效制定并使用产品Backlog,并举一个考务系统的Scrum开发实例进行深入说明,希望可以为刚转型Scrum的传统开发团队提供参考。

An Inventory Model for Items with Two Parameter Weibull Distribution Deterioration and Backlogging

In this paper an inventory model is developed with time dependent power pattern demand and shortages due to deterioration and demand. The deterioration is assumed to follow a two parameter Weibull distribution. Three different cases with complete, partial, no backlogging are considered. The optimal analytical solution of the model is derived. Suitable numerical example has been discussed to understand the problem. Further sensitivity analysis of the decision variables has been done to examine the effect of changes in the values of the parameters on the optimal inventory policy.

Metropolitan Housing Development in Urban Fringe Areas-A Case Study of Three Metropolitan Cities of South Africa: Johannesburg, Ekurhuleni and Tshwane

Purpose:The metropolitan cities of Johannesburg,Ekurhuleni and Tshwane play an important role in the economy of the Gauteng province in South Africa.The region constitutes to 22.4 percent of the total population of South Africa and has a strong presence and contributes in areas of manufacturing sector,financial and business services,retail and wholesale trade,etc.The rapid urban population,increase in the informal settlements and socio-economic opportunities has resulted in considerable urban sprawl in and around the urban fringe areas of these metropolitan cities.The urban fringe areas of these metros often come under the influence of rapid urbanization process and pressures.Coupled with the economical and potential land dynamics and lack of priority of spatial development guidelines,these areas attract rapid and haphazard development from communities and developers.Research Design/Methodology:This research is based on a qualitative approach through a comprehensive literature review that included content analysis of key documents on housing sector such as IDPs(Integrated Development Plans),Municipal Annual Reports,Growth Development Strategies,and among other sectoral documents on housing sector.Some of the key priority issues considered in the housing sector included:eradication of housing backlogs,spatial restructuring of housing,provision of choice in terms of location,tenure and housing typology.Findings:The current paper discusses the approaches of metropolitan housing development processes in three metropolitan cities of South Africa from Gauteng region,namely:Johannesburg,Ekurhuleni and Tshwane.The paper discusses the existing housing sectoral scenario along with the fringe areas in three cities with focus on:formal and informal settlements,housing segregation and the backlogs,current institutional arrangements,role of public private participation,and scope for alternate mechanisms.The paper concludes in discussion on sustainable development options for housing development in urban fringe areas.

清代清理积案的理念、制度及实效

清代案件积压现象一直存在,至清中后期积案已经成为比较严重的社会问题。清代主要以行政追责为手段强化各级官员监督,且将官员个人勤勉作为解决积案问题的关键。中央和地方为应对积案问题在制度规范方面多有着力。中央不断完善相关立法,地方各省除制定清理积案相关法律规范外,通常还会设置专门机构或人员进行处理。实践中,清代将治理积案的核心放置于“整饬吏治”,且多采取短期内“运动式”的方式消除积案“存量”,此种做法虽取得了一定成效,但效果有限,无法从根本上解决问题。其中固然有案件繁多、司法资源有限、吏治疲玩等因素,但更深层次的原因则是清代无立案限制且案件审理权责集中于正长官(印官)的司法体制。

考虑非平稳随机过程的机场旅检通道服务资源配置优化

针对机场旅客到达过程的非平稳性和随机性造成旅检通道需求不确定且具备高时变性、配置难度大这一问题,提出一种非平稳排队模型嵌入遗传算法的方法。建立具有多个并行服务台的单阶段服务系统的非平稳排队模型,将输入过程和服务过程拟合为一般分布,并提出拓展的积压后移平稳(stationary backlog-carryover,SBC)近似,以快速求解系统性能指标值。提出一种将拓展的SBC近似嵌入遗传算法的优化方法,设计实验算例和优化算例。通过解析结果与仿真结果进行对比,验证拓展SBC近似的精确性以及优化方法的有效性,并分析非平稳性对系统性能以及优化结果的影响。将该方法应用在实际案例中,结果表明,优化后的配置方案比实际配置方案减少了14.80%的旅检通道数量,这证明该方法是有效的。

POLYNOMIAL DYNAMIC PROGRAMMING ALGORITHMS FOR LOT SIZING MODELS WITH BOUNDED INVENTORY AND STOCKOUT AND/OR BACKLOGGING

This paper addresses a dynamic lot sizing problem with bounded inventory and stockout where both no backlogging and backlogging allowed cases are considered. The stockout option means that there is outsourcing in a period only when the inventory level at that period is non-positive. The production capacity is unlimited and production cost functions are linear but with fixed charges. The problem is that of satisfying all demands in the planning horizon at minimal total cost. We show that the no backlogging case can be solved in O（T^2） time with general concave inventory holding and outsourcing cost functions where T is the length of the planning horizon. The complexity can be reduced to O（T） when the inventory holding cost functions are also linear and have some realistic properties, even if the outsourcing cost functions remain general concave functions. When the inventory holding and outsourcing cost functions are linear, the backlogging case can be solved in O（ T^3 logT） time whether the outsourcing level at each period is bounded by the sum of the demand of that period and backlogging level from previous periods, or only by the demand of that period.

An EPQ model with variable production,probabilistic deterioration and partial backlogging under inflation

This paper develops an economic production quantity(EPQ)model under the effect of inflation and time value of money.The rate of replenishment is considered to be a variable and the generalized unit production cost function is formulated by incorporating several factors,such as raw material,labour,replenishment rate,advertisements and other factors of the manufacturing system.The selling price of a unit is determined by a mark-up over the production cost.We have considered three types of continuous probabilistic deterioration function,and also considered that the holding cost of the item per unit time is assumed to be an increasing linear function of time spent in storage.In addition,shortages are allowed and partially backlogged.This model aids in minimizing the total inventory cost by finding the optimal cycle length and the optimal production quantity.The optimal solution of the model is illustrated with the help of numerical examples.

Two-warehouse inventory model for non-instantaneous deteriorating items with optimal credit period and partial backlogging under inflation

This paper analyses an inventory model for non-instantaneous deteriorating items under a two-warehouse system with the effect of inflation and time value of money.We propose the model from the seller’s prospective by incorporating the fact that granting the trade credit from the seller to its buyer not only increases sales and revenue but also opportunity cost and default risk.Moreover,in this model,shortages are allowed and partially backlogged.The backlogging rate is dependent on the waiting time for the next replenishment.The purpose of this study is to determine the optimal credit period and the optimal order quantity such that the total profit of the seller is maximised.Some numerical examples are presented for illustrating the proposed inventory model.Furthermore,sensitivity analysis of the optimal solutions with respect to major parameters is carried out and some managerial inferences are obtained.

An EOQ model for non-instantaneous deteriorating items with timedependent demand under partial backlogging

This article discusses an economic order quantity model for non-instantaneous deteriorating items in which the demand is assumed to be a linear function of time over an infinite planning horizon.In addition,the salvage value associated with the deteriorated units is also considered.The shortages are allowed and partially backlogged.A mathematical model is framed to obtain the replenishment policy which aids the retailer to minimize the total inventory cost.The objective of this work is to minimize the total inventory cost and to find the optimal length of replenishment and the optimal order quantity.The theory developed in this article is illustrated using numerical examples.A computational algorithm is designed to find the optimal solution.Sensitivity analysis is carried out to study the changes in the effect on the optimal solutions and some managerial insights are obtained.

An inventory model for non-instantaneous deteriorating items with multivariate demand and backlogging under inflation

In this paper,a deterministic inventory model for non-instantaneous deteriorating items with price-and time-dependent demand with inflation is developed.The demand is continuous and differentiable function of price and time.Shortages are allowed and the unsatisfied demand is partially backlogged at a negative exponential rate with the waiting time.The objective is to find the optimal replenishment cycle such that present value of total profit is maximized,for any given selling price.We then provide a simple algorithm to find the optimal selling price and replenishment schedule for the proposed model that can be easily implemented by practitioners.Comparisons of the present model with various cases are presented as the special case.Numerical examples are used to illustrate the theoretical results and the sensitivity analysis with respect to major parameters on the optimal solutions is also performed.

Partial backlogging inventory model with price and stock level dependent demand,time varying holding cost and quantity discounts

This article deals with an increasing total profit for inventory optimal ordered quantity and partial backlogging with the holding cost depending on the storage time period,and the rate of market demand is assumed to fluctuate as a function,based on level of stock and selling price.Thereafter,using the concept of a Hessian matrix,we have proved the concave nature of the profit function for the case where maximum cost is obtained.Finally,in order to validate the derived models,numerical examples and sensitivity analysis are explained.Through numerical test,we show that the proposed algorithms give quite satisfactory solutions.Hence,it can be concluded that the total profit can be increased by allowing shortage and partial backlogging.

An EOQ model of non-instantaneous deteriorating items with price,time-dependent demand and backlogging

This paper considers an inventory model with non-instantaneous deteriorating item in which demand rate is a function of selling price and time,taking account of time value of money.This paper aids the retailer in maximising the total profit by determining optimal replenishment policies.Shortages are allowed which are partially backlogged.This model also takes into cognizance the fact that in business activities nowadays customers are given delay in payments.Under these assumptions,a mathematical model is formulated over a finite planning horizon and then some useful theoretical results have been framed to characterise the optimal solutions.The necessary and sufficient conditions for the existence and the uniqueness of the optimal solutions are also derived.An algorithm is designed to find the optimum solutions of the proposed model.Numerical examples are included to illustrate the algorithmic procedure and the effects of key parameters are studied to analyse the behaviour of the model.

优化配料结构在酒钢本部烧结机的应用

酒钢地理位置、交通状况、销售半径等与大多数钢企相比处于劣势,性价比高的自有资源的充分利用,成为提高盈利能力最直接,也是最有效的途径,但受镜铁山矿服务年限影响,自制综合铁精矿产量无法满足烧结用料需求,尤其是2020年7月本部7#高炉投产后,烧结工序综合外购精矿配比保持在12%~13%,高价铁料资源影响铁水成本持续上升,成本传递严重影响吨钢利润,且由于各种铁料的成分千差万别,每种成分对成本和产品质量的影响程度也不相同,影响铁水成本及质量稳定控制。因此,有必要通过对各种铁料进行经济性评价,并积极消化低价积压资源,在保证质量稳定的同时,尽可能降低成本,以缓解当前生产经营状况。

服务时间累积量控制的Geo^(X)/G/1排队的稳态队长

考虑服务台的启动由服务台闲期所有到达的服务时间累积之和(即顾客即将被服务的时间累积量)控制的离散时间批到达Geo^(X)/G/1排队服务系统。顾客成批到达系统,当顾客的被服务时间累积量超过某个非负整数D时,服务台立刻为顾客提供服务直到忙期结束(此策略被称为D策略)。该模型可为无线传感网络的从业者提供一些理论基础。首先,在准备工作中,讨论了忙期开始时刻的顾客数、服务时间累积量以及服务台的忙期和闲期分布;然后,通过闲、忙期到达顾客的分类和概率分析方法,研究了系统的离去时刻稳态队长和任意时刻n^(+)的稳态队长分布的概率母函数。作为特例,分析得到了离散时间Geo^(X)/G/1排队和D策略离散时间Geo/G/1排队的队长分布结果。最后,模拟分析了一类无线传感节点,并在数值上获得了节点的最低能耗。

基于产品生命周期的战略库存与动态定价决策研究

本文考虑一个基于短周期产品供应商和零售商组成的两级供应链系统,在两个销售周期内,市场容量根据产品所处的生命周期变化而变化。文章研究了在承诺定价合同和动态定价合同下,零售商使用战略库存策略和战略缺货策略的条件,以及产品在不同生命周期下供应商和零售商的最优决策和利润。研究发现,战略库存策略和战略缺货策略在两种定价合同下都可能存在,产品所处生命周期和持有(缺货)成本的大小对供应链成员的决策和利润起着决定性作用。战略库存策略在产品处于发展期时可以有效降低产品第二期批发价格,但战略缺货策略却不具备议价效果。同时,当第二周期产品市场容量变化不剧烈,且持有成本较小时,零售商在动态定价合同下使用战略库存策略可以同时提高供应商和零售商利润,进而提高整体供应链效率;零售商在动态定价合同下使用战略缺货策略同样可以提高整体供应链效率,但当供应商决定供应链成员间的定价方式时,战略缺货策略始终不会存在。