Customer Locations Research Articles

A tabu search heuristic for a routing problem arising in servicing of offshore oil and gas platforms

This paper introduces a pickup and delivery problem encountered in servicing of offshore oil and gas platforms in the Norwegian Sea. A single vessel must perform pickups and deliveries at several offshore platforms. All delivery demands originate at a supply base and all pickup demands are also destined to the base. The vessel capacity may never be exceeded along its route. In addition, the amount of space available for loading and unloading operations is limited at each platform. The problem, called the Single Vehicle Pickup and Delivery Problem with Capacitated Customers consists of designing a least cost vehicle (vessel) route starting and ending at the depot (base), visiting each customer (platform), and such that there is always sufficient capacity in the vehicle and at the customer location to perform the pickup and delivery operations. This paper describes several construction heuristics as well as a tabu search algorithm. Computational results are presented.

Modes of innovation in knowledge-intensive business services evidence from Lombardy

The present paper investigates the sectoral variety and common patterns across different typologies of knowledge-intensive business services (KIBS). We examine this issue by considering the case of Lombardy, a highly developed manufacturing area the industrial activities of which are experiencing a pervasive transformation towards higher knowledge content, demanding stronger and more pervasive support by advanced services. Drawing on an original survey-based firm-level dataset, we analyze innovation patterns across KIBS, evaluating the explanatory power of traditional classifications of the service sector, as well as the heterogeneity driven by firm and market specific characteristics. Our findings highlight four profiles of KIBS: interactive innovation mode, product innovation mode, conservative innovation mode and techno-organizational innovation mode. When examining in more depth the variables that are associated with cluster membership, we find that firm strategy is the most significant determinant, with size, customer location, and training also playing a role in defining cluster specificities.

Discrete approximation heuristics for the capacitated continuous location–allocation problem with probabilistic customer locations

The capacitated continuous location–allocation problem, also called capacitated multisource Weber problem (CMWP), is concerned with locating m facilities in the Euclidean plane, and allocating their capacity to n customers at minimum total cost. The deterministic version of the problem, which assumes that customer locations and demands are known with certainty, is a nonconvex optimization problem. In this work, we focus on a probabilistic extension referred to as the probabilistic CMWP (PCMWP), and consider the situation in which customer locations are randomly distributed according to a bivariate probability distribution. We first formulate the discrete approximation of the problem as a mixed-integer linear programming model in which facilities can be located on a set of candidate points. Then we present three heuristics to solve the problem. Since optimal solutions cannot be found, we assess the performance of the heuristics using the results obtained by an alternate location–allocation heuristic that is originally developed for the deterministic version of the problem and tailored by us for the PCMWP. The new heuristics depend on the evaluation of the expected distances between facilities and customers, which is possible only for a few number of distance function and probability distribution combinations. We therefore propose approximation methods which make the heuristics applicable for any distance function and probability distribution of customer coordinates.

Sysco Corp.

AbstractRetail ‐ Food & Beverage (MIC: SIC: 5141 NAIC: 424410)Sysco distributes food and related products primarily to the foodservice or ‘food‐prepared‐away‐from‐home’ industry. At June 30 2007, Co. served about 391,000 customers, including restaurants, healthcare and educational facilities, lodging establishments and other foodservice customers. Co.'s Breadline segment distributes a line of food and non‐food products to traditional and chain restaurant customers. Co.'s SYGMA segment distributes a line of food and non‐food products to chain restaurant customer locations. Co.'s other segments include its specialty produce, custom‐cut meat and lodging industry products segments and a company that distributes to internationally located chain restaurants.

Sequential versus simultaneous approach in the location and design of two new facilities using planar Huff-like models

Companies frequently decide on the location and design for new facilities in a sequential way. However, for a fixed number of new facilities, the company might be able to improve its profit by taking its decisions for all the facilities simultaneously. In this paper we compare three different strategies: simultaneous location and independent design of two facilities in the plane, the same with equal designs, and the sequential approach of determining each facility in turn. The basic model is profit maximization for the chain, taking market share, location costs and design costs into account. The market share captured by each facility depends on the distance to the customers (location) and its quality (design), through a probabilistic Huff-like model. Recent research on this type of models was aimed at finding global optima for a single new facility, holding quality fixed or variable, but no exact algorithm has been proposed to find optimal solutions for more than one facility. We develop such an exact interval branch-and-bound algorithm to solve both simultaneous location and design two-facility problems. Then, we present computational results and exhibit the differences in locations and qualities of the optimal solutions one may obtain by the sequential and simultaneous approaches.

Sysco Corp.

AbstractRetail ‐ Food & Beverage (MIC: 5.3 SIC: 5141 NAIC: 424410)Sysco is engaged in the distribution of food and related products to the foodservice or ‘food‐prepared‐away‐from‐home’ industry. As of June 30 2007, Co. provided these services to about 391,000 customers, including restaurants, healthcare and educational facilities, lodging establishments and other foodservice customers. Co.'s Breadline segment distributes a line of food products and non‐food products to both traditional and chain restaurant customers. Co.'s SYGMA segment distributes a line of food products and non‐food products to certain chain restaurant customer locations. The Other segment includes Co.'s specialty produce, custom‐cut meat and lodging industry products segments.

Reducing energy consumption by using self-organizing maps to create more personalized electricity use information

Identification of electricity use is one of the key elements to motivate customers to promote activities leading more efficient use of energy. Furthermore, electricity use comparisons with other similar customers give more interesting and concrete point of view to examine own consumption habits. In future, electricity providers and retailers are willing and probably forced by legislation to provide such information by the means of energy conservation and efficiency improvement. On the other hand, high number of customers set challenges to handle electricity use data and to create proper comparison information. In this study we present efficient and highly automated way to create comparison groups based on customers building characteristics. The main advantages of the data-based approach are that customer location is noticed, comparison groups are created using concrete building information, data processing is highly automated and also method is computationally efficient. Additionally, presented method provide tool to target and to create customer specific electricity saving guidance. The performance of suggested approach was tested using data set which contained electricity use and building information concerning almost 8000 customers.

Sysco Corp.

AbstractRetail ‐ Food & Beverage (MIC: 5.3 SIC: 5141 NAIC: 424410)Sysco is engaged in the distribution of food and related products to the foodservice or Tood‐prepared‐away‐from‐home' industry. As of June 30 2007, Co. provided these services to about 391,000 customers, including restaurants, healthcare and educational facilities, lodging establishments and other foodservice customers. Co.'s Breadline segment distributes a line of food products and non‐food products to both traditional and chain restaurant customers. Co.'s SYGMA segment distributes a line of food products and non‐food products to certain chain restaurant customer locations. The Other segment includes Co.'s specialty produce, custom‐cut meat and lodging industry products segments.

What you should know about the vehicle routing problem

AbstractIn the Vehicle Routing Problem (VRP), the aim is to design a set of m minimum cost vehicle routes through n customer locations, so that each route starts and ends at a common location and some side constraints are satisfied. Common applications arise in newspaper and food delivery, and in milk collection. This article summarizes the main known results for the classical VRP in which only vehicle capacity constraints are present. The article is structured around three main headings: exact algorithms, classical heuristics, and metaheuristics. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007

Sysco Corp.

AbstractRetail ‐ Food & Beverage (MIC: 5.3 SIC: 5141 NAIC: 424410)Sysco is engaged in the marketing and distribution of food and related products to the foodservice or ‘food‐prepared‐away‐from‐home’ industry. These services are performed for approximately 391,000 customers, including restaurants, healthcare and educational facilities, lodging establishments and other foodservice customers. Co.'s Breadline segment distributes a line of food products and non‐food products to both traditional and chain restaurant customers. Co.'s SYGMA segment distributes a line of food products and non‐food products to certain chain restaurant customer locations. The Other segment includes Co.'s specialty produce, custom‐cut meat and lodging industry products segments.

Waiting Strategies for Anticipating Service Requests from Known Customer Locations

This paper considers a dynamic and stochastic routing problem in which information about customer locations and probabilistic information about future service requests are used to maximize the expected number of customers served by a single uncapacitated vehicle. The problem is modeled as a Markov decision process, and analytical results on the structure of the optimal policy are derived. For the case of a single dynamic customer, we completely characterize the optimal policy. Using the analytical results, we propose a real-time heuristic and demonstrate its effectiveness compared with a series of other intuitively appealing heuristics. We also use computational tests to determine the heuristic value of knowing both customer locations and probabilistic information about future service requests.

English

Providing a common set of technology tools to regulators and reclamation specialists in the Office of Surface Mining (OSM) is helping to streamline the mandates of the Surface Mining Control and Reclamation Act (SMCRA). The Technical Innovation and Professional Services (TIPS) Team consists of 32 people in four OSM offices. In cooperation with State and Tribal regulatory and reclamation agencies, as well as OSM offices nationwide, TIPS provides the latest off-the-shelf scientific and engineering software and hardware tools to federal, state, and tribal experts. These are the same tools used commonly by the mining industry. With the industry regulators and reclamation specialists at the state, tribal, and federal level using the same tools, exchange of information is facilitated and the regulatory and reclamation processes are expedited. This has become an extraordinarily efficient way to carry out the reclamation and regulatory mandates of the Surface Mining Control and Reclamation Act. TIPS began in 1987 as a team of nine persons serving 28 customer locations in 24 states. Today the Team provides scientific and engineering modeling software, hardware, and full training classes to 700 customers in 96 office locations at 24 states, three tribes, and 15 federal offices. This team of innovators holds costs low through shared licensing of the software via the Internet and centralized federal procurement contracts. TIPS also provides full software support and training classes at no cost to its customers. These are specially tailored courses, customized specifically around mining applications of the software. Customers value this training so much that they volunteer as instructors. Over half of all TIPS instructors today come from the customer base. The innovators of TIPS have fostered electronic exchange of data between federal, state, and tribal agencies for 20 years. Their hard work has brought mining reclamation and regulation to increasing levels of efficiency. The most recent two years have brought significant department cooperation and subsequent progress for TIPS, and they continue to pursue new technology and the tools to promote better and more efficient enforcement of the Surface Mining Act. Additional

Sysco Corp.

AbstractRetail ‐ Food & Beverage (MIC: 5.3 SIC: 5141 NAIC: 424410)Sysco is engaged in the marketing and distribution of food and related products to the foodservice or ‘food‐prepared‐away‐from‐home’ industry. These services are performed for approximately 394,000 customers, including restaurants, healthcare and educational facilities, lodging establishments and other foodservice customers. Co.'s Broadline segment distributes a line of food products and non‐food products to both traditional and chain restaurant customers. Co.'s SYGMA segment distributes a line of food products and non‐food products to certain chain restaurant customer locations. The Other segment includes Co.'s specialty produce, custom‐cut meat and lodging industry products segments.

Production and Transportation Integration for a Make-to-Order Manufacturing Company with a Commit-to-Delivery Business Mode

When a make-to-order manufacturing company adopts a commit-to-delivery business mode, it commits a delivery due date for an order and is responsible for the shipping cost. Without loss of generality, we consider that transportation is done by a third-party logistics company, such as FedEx or UPS, which provides multiple shipping modes such as overnight, one-day, two-day delivery, and more. When the transportation time has to be short, clearly, shipping cost is more expensive than it could have been. How should a company schedule production for accepted orders so that the company can leave enough transportation time for orders to take slow shipping modes to reduce the shipping cost? We study this problem of integrating the production and transportation functions for a manufacturing company producing a variety of customized products in a make-to-order environment with a commit-to-delivery mode of business. Various realistic scenarios are investigated in increasing order of complexity. When partial delivery is allowed by customers, we provide both a mixed-integer programming (MIP) model and a minimum cost flow model. We show that nonpreemptive earliest due date (NEDD) production schedules are optimal when partial delivery is allowed and shipping cost is a decreasing convex function with transportation time. When partial delivery is not allowed, we develop an MIP model and prove that the problem is NP-hard. An efficient heuristic algorithm with polynomial computation time is provided for the NP-hard problem. It gives near-optimal production schedules, as shown via thousands of numerical experiments. We also provide models and analysis for other scenarios where shipping cost accounts for customer locations and quantity discounts.

Sysco Corp.

AbstractRetail ‐ Food & Beverage (MIC: 5.3 SIC: 5141 NAIC: 424410)Sysco is engaged in the marketing and distribution of food and related products to the foodservice or ‘food‐prepared‐away‐from‐home’ industry. These services are performed for approximately 394,000 customers, including restaurants, healthcare and educational facilities, lodging establishments and other foodservice customers. Co.'s Breadline segment distributes a line of food products and non‐food products to both traditional and chain restaurant customers. Co.'s SYGMA segment distributes a line of food products and non‐food products to certain chain restaurant customer locations. The Other segment includes Co.'s specialty produce, custom‐cut meat and lodging industry products segments.

A cluster-based optimization approach for the multi-depot heterogeneous fleet vehicle routing problem with time windows

This paper presents a novel three-phase heuristic/algorithmic approach for the multi-depot routing problem with time windows and heterogeneous vehicles. It has been derived from embedding a heuristic-based clustering algorithm within a VRPTW optimization framework. To this purpose, a rigorous MILP mathematical model for the VRPTW problem is first introduced. Likewise other optimization approaches, the new formulation can efficiently solve case studies involving at most 25 nodes to optimality. To overcome this limitation, a preprocessing stage clustering nodes together is initially performed to yield a more compact cluster-based MILP problem formulation. In this way, a hierarchical hybrid procedure involving one heuristic and two algorithmic phases was developed. Phase I aims to identifying a set of cost-effective feasible clusters while Phase II assigns clusters to vehicles and sequences them on each tour by using the cluster-based MILP formulation. Ordering nodes within clusters and scheduling vehicle arrival times at customer locations for each tour through solving a small MILP model is finally performed at Phase III. Numerous benchmark problems featuring different sizes, clustered/random customer locations and time window distributions have been solved at acceptable CPU times.

Territory Planning and Vehicle Dispatching with Driver Learning

This paper investigates the construction of routes for local delivery of packages. The primary objective of this research is to provide realistic models to optimize vehicle dispatching when customer locations and demands vary from day to day while maintaining driver familiarity with their service territories, hence dispatch consistency. The objective of increasing driver familiarity tends to make routes or service territories fixed. On the other hand, to serve varying demand it is advantageous to reassign vehicles/drivers and service territories each day. To balance the trade-offs between these two objectives, we developed the concepts of “cell,” “core area,” and “flex zone,” and created a two-stage vehicle routing model—strategic core area design and operational cell routing—and explicitly evaluated the effect of driver familiarity through the use of learning and forgetting curves.

On the multi-product packing-delivery problem with a fixed route

We study a variation of the packing-delivery problem, which involves K distinct products, a single capacitated truck, and a fixed sequence of customer locations to be visited. We show that the non-split version of the problem is strongly polynomial solvable. For the split delivery case, we analyze the conditions of optimality and propose a local optimization algorithm with a computational complexity of O( n 3 log( n)). Based on 14,000 randomly generated test problems, a consistent performance improvement achieved by the proposed local optimization algorithm over that by the optimal non-split packing-delivery schedules is observed.

Sysco Corp.

AbstractRetail — Food & Beverage (MIC: 5.3 SIC: 5141 NAIC: 424410)Sysco is engaged in the marketing and distribution of food and related products to the foodservice or ‘food‐prepared‐away‐from‐home’ industry. These services are performed for approximately 394,000 customers. Co.'s Breadline segment distributes a full line of food products and non‐food products to both traditional and chain restaurant customers. The SYGMA segment distributes a full line of food products and non‐food products to certain chain restaurant customer locations. The Other segment includes Co.'s specialty produce, custom‐cut meat and lodging industry products segments.

Solving a Dynamic and Stochastic Vehicle Routing Problem with a Sample Scenario Hedging Heuristic

The statement of the standard vehicle routing problem cannot always capture all aspects of real-world applications. As a result, extensions or modifications to the model are warranted. Here we consider the case when customers can call in orders during the daily operations; i.e., both customer locations and demands may be unknown in advance. This is modeled as a combined dynamic and stochastic programming problem, and a heuristic solution method is developed where sample scenarios are generated, solved heuristically, and combined iteratively to form a solution to the overall problem.