Digital Commons Network^™

A Scalable Algorithm For Locating Distribution Centers On Real Road Networks, Saeed Ghanbartehrani, Jose D. Porter

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

The median problem is a type of network location problem that aims at finding a node with the total minimum demand weighted distance to a set of demand nodes in a weighted graph. In this research, an algorithm for solving the median problem on real road networks is proposed. The proposed algorithm, referred to as the multi-threaded Dijkstra’s (MTD) algorithm, is then used to optimally locate Wal-Mart distribution centers on the 28-million node road network of the United States with the objective of minimizing the total demand weighted transportation cost. The resulting optimal location configuration of Wal-Mart distribution centers improves …

Progress In Material Handling Research: 2016

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

Table of contents.

Continuous Approximation Of Multi Cycle Time For Multi Aisles Automated Storage And Retrieval Systems., Yassine Boudghene Stambouli, Latefa Ghomri

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

Knowing that, in an automated storage and retrieval system, the travel time of the storage/retrieval machine is an important parameter which affects the whole system performances, several works were dedicated to its evaluation and its modeling, in single, dual and multi command. These models were proposed for different configurations of AS/RS; such as unit load, multi-aisles and Mobile Racks. These models are based mainly on a discrete approach and the analytical expressions represent the system functioning exactly. In this paper we present a general approach for analytical modeling of multi command cycle time by giving particularly the modeling of the …

New Design Guidelines For In-Plant Milk-Run Systems, Thorsten Schmidt, Ingolf Meinhardt, Frank Schulze

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

Tugger trains became a popular means of supply in material handling intensive production systems. In contrast to forklift trucks they interlink a supermarket with multiple delivery locations along a transport route in a milk-run. But the efficiency gain (higher transport capacity, reduced labor costs) has its price: Compared to forklift trucks, planning and dimensioning of in-plant milk-run systems is more complicated. The paper discusses features and drawbacks of a recent standardization approach of the Association of German Engineers (VDI) and highlights the variety of technical restrictions which have to be considered when a milkrun system is designed. It shows, that …

The Storage Replenishment Problem In Rectangular Warehouses, Haldun Sural, Claudia Archetti, Melih Celik

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

In warehouses, storage replenishment operations involve the transportation of items to capacitated item slots in forward storage area from reserve storage. These items are later picked from these slots as their demand arises. While order picking constitutes the majority of warehouse operating costs, replenishment operations might be as costly in warehouses where pick lists generally consist of only a few lines (e.g., order fulfillment warehouses). In this study, we consider the storage replenishment problem in a parallel-aisle warehouse, where replenishment and order picking operations are carried out in successive waves with time limits. The aim is to determine the item …

Job Sequencing In A Miniload System, Lennart Baardman, Kees Jan Roodbergen

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

More and more warehouses shift towards the use of automated systems. One such system is a miniload system. In this system, a crane retrieves bins from their storage locations and brings the bins to the picking station, where a worker takes the requested products from the retrieved bins. After a product has been picked, the bin is put back by the crane in its original location. A buffer is present at the picking station to absorb fluctuations in speed between the picker and the crane. The problem of scheduling jobs in this system has received little attention in the literature. …

A Performance Measurement Framework And Solution Approach For The Integrated Facility Layout Problem With Uncertain Demand, Melih Celik, Begun Efeoglu, Haldun Sural

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

The integrated facility layout problem (IFLP) focuses on the simultaneous determination of the relative locations of multiple copies of capacitated equip- ment or machinery in a facility, as well as the material ow between these units. In this paper, we consider the IFLP in the existence of uncertain demand for the products of the facility. Motivated by the framework for next generation facility layouts by Benjaafar et al. (2002), we extend the approaches in the lit- erature for distributed facility layouts to the case of dynamic demand and the possibility of relayouts, and propose a heuristic solution approach to minimize …

Energy And Cycle Time Efficient Warehouse Design For Autonomous Vehicle-Based Storage And Retrieval System, Banu Yetkin Ekren, Tone Lerher

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

This study explores the best warehouse design for an autonomous vehicle based storage and retrieval system (AVS/RS) minimizing average energy consumption per transaction and average cycle time per transaction, simultaneously. In the design concept, we consider, rack design in terms of number of bays, number of tiers, number of aisles; number of resources, namely number of autonomous vehicles and lifts and; velocity profiles of lifts and autonomous vehicles in the AVS/RS. We completed 1,296 number of experiments in simulation to obtain Pareto solutions representing the “average energy consumption per transaction” and “average cycle time per transaction” trade-offs based on designs …

A Simulation Model To Evaluate The Layout For Block Stacking Warehouses, Shahab Derhami, Jeffrey S. Smith, Kevin R. Gue

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

Storing pallets of Stock Keeping Units (SKU's) on top of another in lanes on a warehouse floor is known as block stacking. This storage system is widely used in manufactoring systems and distribution centers. The arrangement of lanes in the layout of this system significantly impacts utilization of the storage space and transportation costs. Existing research that studies the layout for this system focuses exclusively on determining the optimal lane depth with respect to space utilization and ignores transportation costs. In this study, we develop a stimulation model that computes several performance metrics to evaluate both of these objectives for …

A Novel Approach To Analyze Inventory Allocation Decisions In Robotic Mobile Fulfillment Systems, Tim Lamballais, Debjit Roy, M.B.M De Koster

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

The Robotic Mobile Fulfillment System is a newly developed automated, parts-to-picker material handling system. Storage shelves, also known as inventory pods, are moved by robots between the storage area and the workstations, which means that they can be continually repositioned during operations. This paper develops a queueing model for optimizing three key decision variables: (1) the number of pods per product (2) the ratio of the number of pick to the number of replenishment stations, and (3) the replenishment level per pod. We show that too few or too many pods per product leads to unnecessarily long order throughput times, …

Operational-Level Optimization Of Inbound Intralogistics, Hector J. Carlo, Yeiram Martinez

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

This study is concerned with optimizing inbound operations at distribution centers (DCs), warehouses, and cross-docks with staging areas. The objective of the problem is to minimize the makespan required to move all unit loads from the trailers to the flow racks, and from the flow racks to their respective storage locations. It is assumed that a set of inbound trailers with known composition have been assigned and sequenced to inbound dock doors. The following three inbound logistics decisions are simultaneously considered: i) unloaders’ assignment and scheduling, ii) loads-to-flow rack assignment, and iii) assignment and haulers’ scheduling. In this study we …

Introducing The Concept Of Hyperconnected Mobile Production, Suzanne Marcotte, Benoit Montreuil

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

Many globalized businesses are trying to cope with growing competition by strategically expanding their dedicated network of production facilities so as to be able to offer and to deliver time and price competitive offers to their clients across the world. In this paper, exploiting Physical Internet principles, we introduce the concept of hyperconnected mobile production that can alternatively enable businesses to dynamically expand and contract as necessary their production capacity in regions worldwide. First, hyperconnected mobile production exploits open fabs from multiple parties readily available in those regions. Second, these fabs are to rely on plug-and-play production modules. These modules …

Logistics Models To Support Order-Fulfillment From The Sea, Jennifer Pazour, Ian Shin

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

Sea based logistics use maritime platforms to transfer cargo stored on vessels and delivers them ashore. This chapter describes the motivations and logistical requirements of seabasing. The sea base’s organizational structure, its material handling environment, and the internal cargo flow processes of the T-AKE vessel are described. Three seabasing distribution network scenarios -- Iron Mountain, Skin-to-Skin Replenishment, and Tailored Resupply Packages -- are described and mapped to warehousing and distribution networks, characteristics, and decision problems. Finally, related literature is reviewed and open areas for logistics research to support order fulfillment from the sea are identified.

Maritime Location Decisions For Lng Bunkering Facilities, Reinier C. Schneider, Iris F.A. Vis

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

Liquefied natural gas (LNG) is one of the upcoming fuels to be used for more sustainable shipping activities in the maritime sector. For a widespread adoption by end-users, a refuelling network requiring capital intensive investments, needs to be in place. From a macro perspective of suppliers of LNG, it makes sense to develop the infrastructure at strategic locations that capture as many vessels and ships as possible. The goal of this research is to develop a facility location model that can contribute to the location selection of LNG facilities in a new fuelling network. The new model will fit the …

Methodology For Choosing An Appropriate Inland Vessels As A Floating Distribution Centers, Andrea Seidlova, David Sourek

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

The primary goal of this paper is to propose a methodology for the choice of an appropriate vessel type under the specific condition of floating distribution center. The right choice of the appropriate type of vessel has a fundamental influence on the long-term success of city logistic projects with water transport. In this paper, we propose a methodology for vessel choice according to its inner layout and technology of handling. The possibility of an application in practice will be defined for each option.

Integrated Versus Sequential Scheduling And Assignment At A Unit Load Cross-Dock, Arpan Rijal, Marco Bijvank, Rene De Koster

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

Within a cross-dock, the assignment of trucks to dock-doors and the scheduling of trucks to be processed are two major operational decisions. Conventionally, assignment and scheduling decisions are made sequentially. However, solving the two problems sequentially can lead to sub-optimal solutions because the objectives of the two problems are in conflict with each other. To gain further insights, we create an integrated model which is capable of simultaneously scheduling and assigning trucks at cross-docks. We contrast the integrated model with a sequential model which first schedules trucks for processing and then assigns them to dock-doors. Experiments demonstrate that the integrated …

A Lagrangian Relaxation For Capacitated Single Allocation P-Hub Median Problem With Multiple Capacity Levels, Ching-Jung Ting, Kuo-Rui Lu

14th IMHRC Proceedings (Karlsruhe, Germany – 2016)

In this paper we consider a capacitated single allocation p-hub median problem with multiple capacity levels (CSApHMPMC) in which the decisions are to determine the location of p hubs and their capacity levels, the single allocation of non-hub nodes to hubs in the logistics network. This problem is formulated as an integer programming model with the objective of minimizing the sum of total transportation cost and fixed cost of the selected p hubs with established capacity levels. A Lagrangian relaxation (LR) approach is proposed to solve the CSApHMPMC. The Lagrangian function that we formulated decomposed the original problem into smaller …

An Edge-Swap Heuristic For Finding Dense Spanning Trees, Mustafa Ozen, Hua Wang, Kai Wang, Demet Yalman

Theory & Applications of Graphs

Finding spanning trees under various restrictions has been an interesting question to researchers. A "dense" tree, from a graph theoretical point of view, has small total distances between vertices and large number of substructures. In this note, the "density" of a spanning tree is conveniently measured by the weight of a tree (defined as the sum of products of adjacent vertex degrees). By utilizing established conditions and relations between trees with the minimum total distance or maximum number of sub-trees, an edge-swap heuristic for generating "dense" spanning trees is presented. Computational results are presented for randomly generated graphs and specific …

Path-Factors Involving Paths Of Order Seven And Nine, Yoshimi Egawa, Michitaka Furuya

Theory & Applications of Graphs

In this paper, we show the following two theorems (here c_i(G-Χ) is the number of components C of G-Χ with |V(C)|=i): (i) If a graph G satisfies c₁(G-Χ)+⅓c₃(G-Χ)+⅓c₅(G-Χ) ≤ ⅔ |Χ| for all Χ ≤ V(G), then G has a {Ρ₂},Ρ₇}-factor. (ii)If a graph G satisfies c₁}(G-Χ)+c₃}(G-Χ)+⅔ c₅}(G-Χ)+⅓c₇}(G-Χ) ≤ ⅔|Χ| for all Χ⊆ V(G), then G has a {P₂,P₉}-factor.

Classifying Resolving Lists By Distances Between Members, Paul Feit

Theory & Applications of Graphs

Let G be a connected graph and let w₁,…w_r be a list of vertices. We refer the choice of a triple (r;G;w₁,…w_r), as a metric selection. Let ρ be the shortest path metric of G. We say that w₁,…w_r resolves G (metricly) if the function c:V(G) → ℤ^r given by

x → (ρ (w1,x),…,ρ(wr,x))

is injective. We refer to c as the code map and to its image as the codes of the triple (r;G;w₁,…,w_r).

This paper proves basic results …

Chapter 11: Distinctive Contours Of Jesuit Enlightenment In France, Jeffrey D. Burson

History: Faculty Publications

Work published in Exploring Jesuit Distinctiveness: Interdisciplinary Perspectives on Ways of Proceeding within the Society of Jesus.

Induced Subgraph Saturated Graphs, Craig M. Tennenhouse

Theory & Applications of Graphs

A graph G is said to be H-saturated if G contains no subgraph isomorphic to H but the addition of any edge between non-adjacent vertices in G creates one. While induced subgraphs are often studied in the extremal case with regard to the removal of edges, we extend saturation to induced subgraphs. We say that G is induced H-saturated if G contains no induced subgraph isomorphic to H and the addition of any edge to G results in an induced copy of H. We demonstrate constructively that there are non-trivial examples of saturated graphs for …

On Minimum Spanning Subgraphs Of Graphs With Proper Connection Number 2, Zhenming Bi, Gary Chartrand, Garry L. Johns, Ping Zhang

Theory & Applications of Graphs

An edge coloring of a connected graph G is a proper-path coloring if every two vertices of G are connected by a properly colored path. The minimum number of colors required of a proper-path coloring of G is called the proper connection number pc(G) of G. For a connected graph G with proper connection number 2, the minimum size of a connected spanning subgraph H of G with pc(H) = 2 is denoted by μ(G). It is shown that if s and t are integers such that t ≥ s + 2 ≥ 5 …

A Content Analysis: The Relationship Between Sentiment, Gender And Time Of Day In Ewom, Katie Bass, Laicelis Haro, Xiaotong Liu, Jaejin Liu

AMTP Proceedings 2016

This content analysis looks at several trends regarding electronic Word of Mouth (eWOM) and how consumers engage in eWOM. 304 tweets were analyzed and numerous correlations regarding gender and time-of-day. This research will be beneficial to brands and companies seeking to launch new products or services using social media as a promotional avenue.

Scm?, Stephen A. Lemay, Dave Mcmahon, Jeffery A. Periatt

AMTP Proceedings 2016

Supply chain management remains a young field, one that has struggled to define itself in the most literal sense. This research looks at some of the most available definitions of supply chain management, analyzes their content, and explains the essence of the definitional problem. It does not attempt to define supply chain management--that would be a bit like driving onto a crowded road while complaining about the traffic--but it does attempt to lay out the path or paths that need to be followed to arrive at a consensus definition.

A Class Of Graphs Approaching Vizing's Conjecture, Aziz Contractor, Elliot Krop

Theory & Applications of Graphs

For any graph G=(V,E), a subset S ⊆ V dominates G if all vertices are contained in the closed neighborhood of S, that is N[S]=V. The minimum cardinality over all such S is called the domination number, written γ(G). In 1963, V.G. Vizing conjectured that γ(G □ H) ≥ γ(G)γ(H) where □ stands for the Cartesian product of graphs. In this note, we define classes of graphs Α_n, for n≥0, so that every graph belongs to some such class, and Α₀ corresponds to class A of Bartsalkin and German. We prove that …

Eternal Independent Sets In Graphs, Yair Caro, William F. Klostermeyer

Theory & Applications of Graphs

The use of mobile guards to protect a graph has received much attention in the literature of late in the form of eternal dominating sets, eternal vertex covers and other models of graph protection. In this paper, eternal independent sets are introduced. These are independent sets such that the following can be iterated forever: a vertex in the independent set can be replaced with a neighboring vertex and the resulting set is independent.

Group-Antimagic Labelings Of Multi-Cyclic Graphs, Dan Roberts, Richard M. Low

Theory & Applications of Graphs

Let Α be a non-trivial abelian group. A connected simple graph G = (V, E) is Α-antimagic if there exists an edge labeling f: Ε(G) → A \{0} such that the induced vertex labeling f+: V(G) → Α, defined by f+(v) = Σ{f(u,v): (u, v) ∈ E(G)}, is a one-to-one map. The integer-antimagic spectrum of a graph G is the set IAM(G) = {κ: G is ℤ_k - antimagic and κ ≥ 2}. In this paper, we analyze the integer-antimagic spectra for various classes of multi-cyclic graphs.

Improving The Inference Of Some Experiemtal Studies By Using Ranked Auxiliary Covariates, Rajai Jabrah

College of Graduate Studies: Theses & Dissertations

In many studies, the measurement of sampling units according to the response variable is costly or time consuming, however, it is possible to rank sampling units according to baseline auxiliary covariates, which are available, easily obtainable, and cost efficient. In these cases, when estimating the population mean, Ranked Set Sampling (RSS) can be a more efficient sampling method than the Simple Random Sampling (SRS) method. In this dissertation, we propose a modified approach of the RSS method to allocate units into an experimental study, aimed to compare two or more groups.

Ranked auxiliary covariates, which are typically correlated with the …

Garch(1,1) With Sifted Gamma-Distributed Errors, Alan C. Budd

College of Graduate Studies: Theses & Dissertations

Typical General Autoregressive Conditional Heteroskedastic (GARCH) processes involve normally-distributed errors, and they model strictly-positive error processes poorly. This thesis will present a method for estimating the parameters of a GARCH(1,1) process with shifted Gamma-distributed errors, conduct a simulation study to test the method, and apply the method to real time series data.