Product Return Handling

In this article we focus on product return handling and warehousingissues. In some businesses return rates can be well over 20% andreturns can be especially costly when not handled properly. In spiteof this, many managers have handled returns extemporarily. The factthat quantitative methods barely exist to support return handlingdecisions adds to this. In this article we bridge those issues by 1)going over the key decisions related with return handling; 2)identifying quantitative models to support those decisions.Furthermore, we provide insights on directions for future research.reverse logistics;decision-making;quantitative models;retailing and warehousing

Quick Response Practices at the Warehouse of Ankor

In the warehouse of Ankor, a wholesaler of tools and garden equipment, various problems concerning the storage and retrieval of products arise. For example, heavy products have to be retrieved prior to light products to prevent damage. Furthermore, the layout of the warehouse differs from the layout generally assumed in literature. The goal of this research was to determine storage locations for the products and a routing method to obtain sequences in which products are to be retrieved from their locations. It is shown that despite deviations from the "normal" case, similar savings in route length can be obtained by adapting existing solution techniques. Total labor savings are far less than expected on basis of assumptions made in literature. With a minimum of adaptations to the current situation the average route length can be decreased by 30 %. There is no need for complex techniques.storage;warehousing;optimization;case study;routing

High-Level Object Oriented Genetic Programming in Logistic Warehouse Optimization

Disertační práce je zaměřena na optimalizaci průběhu pracovních operací v logistických skladech a distribučních centrech. Hlavním cílem je optimalizovat procesy plánování, rozvrhování a odbavování. Jelikož jde o problém patřící do třídy složitosti NP-težký, je výpočetně velmi náročné nalézt optimální řešení. Motivací pro řešení této práce je vyplnění pomyslné mezery mezi metodami zkoumanými na vědecké a akademické půdě a metodami používanými v produkčních komerčních prostředích. Jádro optimalizačního algoritmu je založeno na základě genetického programování řízeného bezkontextovou gramatikou. Hlavním přínosem této práce je a) navrhnout nový optimalizační algoritmus, který respektuje následující optimalizační podmínky: celkový čas zpracování, využití zdrojů, a zahlcení skladových uliček, které může nastat během zpracování úkolů, b) analyzovat historická data z provozu skladu a vyvinout sadu testovacích příkladů, které mohou sloužit jako referenční výsledky pro další výzkum, a dále c) pokusit se předčit stanovené referenční výsledky dosažené kvalifikovaným a trénovaným operačním manažerem jednoho z největších skladů ve střední Evropě.This work is focused on the work-flow optimization in logistic warehouses and distribution centers. The main aim is to optimize process planning, scheduling, and dispatching. The problem is quite accented in recent years. The problem is of NP hard class of problems and where is very computationally demanding to find an optimal solution. The main motivation for solving this problem is to fill the gap between the new optimization methods developed by researchers in academic world and the methods used in business world. The core of the optimization algorithm is built on the genetic programming driven by the context-free grammar. The main contribution of the thesis is a) to propose a new optimization algorithm which respects the makespan, the utilization, and the congestions of aisles which may occur, b) to analyze historical operational data from warehouse and to develop the set of benchmarks which could serve as the reference baseline results for further research, and c) to try outperform the baseline results set by the skilled and trained operational manager of the one of the biggest warehouses in the middle Europe.

Product Return Handling

In this article we focus on product return handling and warehousing issues. In some businesses return rates can be well over 20% and returns can be especially costly when not handled properly. In spite of this, many managers have handled returns extemporarily. The fact that quantitative methods barely exist to support return handling decisions adds to this. In this article we bridge those issues by 1) going over the key decisions related with return handling; 2) identifying quantitative models to support those decisions. Furthermore, we provide insights on directions for future research

Managing Warehouse Utilization: An Analysis of Key Warehouse Resources

The warehousing industry is extremely important to businesses and the economy as a whole, and while there is a great deal of literature exploring individual operations within warehouses, such as warehouse layout and design, order picking, etc., there is very little literature exploring warehouse operations from a systems approach. This study uses the Theory of Constraints (TOC) to develop a focused resource management approach to increasing warehouse capacity and throughput, and thus overall warehouse performance, in an environment of limited warehouse resources. While TOC was originally developed for reducing operational bottlenecks in manufacturing, it has allowed companies in other industries, such as banking, health care, and the military, to save millions of dollars. However, the use of TOC has been limited to case studies and individual situations, which typically are not generalizable. Since the basic steps of TOC are iterative in nature and were not designed for survey research, modifications to the original theory are necessary in order to provide insight into industry-wide problems. This study further develops TOC\u27s logistics paradigm and modifies it for use with survey data, which was collected from a sample of warehouse managers. Additionally, it provides a process for identifying potentially constrained key warehouse resources, which served as a foundation of this study. The findings of the study confirm that TOC\u27s methods of focused resource capacity management and goods flow scheduling coordination with supply chain partners can be an important approach for warehouse managers to use in overcoming resource capacity constraints to increase warehouse performance

Planning and Scheduling Optimization

Although planning and scheduling optimization have been explored in the literature for many years now, it still remains a hot topic in the current scientific research. The changing market trends, globalization, technical and technological progress, and sustainability considerations make it necessary to deal with new optimization challenges in modern manufacturing, engineering, and healthcare systems. This book provides an overview of the recent advances in different areas connected with operations research models and other applications of intelligent computing techniques used for planning and scheduling optimization. The wide range of theoretical and practical research findings reported in this book confirms that the planning and scheduling problem is a complex issue that is present in different industrial sectors and organizations and opens promising and dynamic perspectives of research and development

İki amaçlı genetik algoritma yaklaşımı ile bir depoda sipariş toplama problemi: Vaka çalışması

In this paper, an order picking problem with the capacitated forklift in a warehouse is studied by considering the total distance and the penalized earliness/tardiness. These objectives are important to reduce transportation costs and to satisfy customer expectations. Since this problem has been known as NP-hard, a genetic algorithm (GA) is proposed to solve the bi-objective order picking problem. The proposed approach is applied to auto components industry that produces wire harnesses responsible for all electrical functions in the vehicle. Experimental design is used for tuning the influential parameters of the proposed GA. The GA approach was solved by weighted sum scalarization.Bu çalışmada, toplam uzaklık ve cezalı erkenlik/gecikme durumlarını dikkate alan bir depoda kapasiteli forklift ile bir sipariş toplama problemi çalışılmıştır. Bu amaçlar, ulaşım maliyetlerini azaltmak ve müşteri beklentilerini karşılamak için önemlidir. Bu problem NP-zor olarak bilindiğinden iki amaçlı sipariş toplama problem çözümü için bir genetik algoritma önerilmiştir. Önerilen yaklaşım, araçtaki tüm elektriksel fonksiyonların çalışmasını sağlayan kablo demetleri üreten bir oto bileşenleri endüstrisine uygulanmıştır. Önerilen GA’nın etkili parametreleri için deney tasarımı kullanılmıştır. GA yaklaşımı ağırlıklı toplam skalerleştirme yöntemi ile çözülmüştür