Mark Goh

A STOCHASTIC MODEL FOR RISK MANAGEMENT IN GLOBAL SUPPLY CHAIN NETWORKS

Abstract With the increasing emphasis on supply chain vulnerabilities, effective mathematical tools for analyzing and understanding appropriate supply chain risk management are now attracting much attention. This paper presents a stochastic model of the multi-stage global supply chain network problem, incorporating a set of related risks, namely, supply, demand, exchange, and disruption. We provide a new solution methodology using the Moreau–Yosida regularization, and design an algorithm for treating the multi-stage global supply chain network problem with profit maximization and risk minimization objectives.

Survey: Covering problems in facility location: A review

In this study, we review the covering problems in facility location. Here, besides a number of reviews on covering problems, a comprehensive review of models, solutions and applications related to the covering problem is presented after Schilling, Jayaraman, and Barkhi (1993). This survey tries to review all aspects of the covering problems by stressing the works after Schilling, Jayaraman, and Barkhi (1993). We first present the covering problems and then investigate solutions and applications. A summary and future works conclude the paper.

Does ISO 9000 certification improve business performance

This paper examines the issue of ISO 9000 certification and its perceived benefits for Singapore based companies. Using an empirical approach, the paper seeks to ascertain if certification has indeed improved the performance for listed and non‐listed companies. The results from a survey of 146 firms suggest that while certification leads to better overall financial performance, non‐listed certified firms experience better documentation procedures, higher perceived quality of products or services, and more effective communication among employees than listed certified firms. Some problems encountered in certification include the failures to establish adequate monitoring programs, to follow set procedures and to carry out appropriate management reviews of the new system as well as unclear authorisation.

CONGESTION MANAGEMENT AND ELECTRONIC ROAD PRICING IN SINGAPORE

Abstract Government and policy makers today face the pressing problem of managing road congestion in urban areas. This paper details the experience of Singapore and the effort made to curb vehicular increase on the roads using a state-of-the-art regulated Electronic Road Pricing (ERP) scheme. Specifically, the paper looks at the public policy effort to forge ahead with road pricing, prepare the island for extensive congestion management, and cap the on-road vehicular population to ensure a smoother flow of commercial transport and distribution.

Performance measurement in supply chain entities: balanced scorecard perspective

Purpose – The purpose of this paper is to empirically examine what senior supply chain executives measure and how they perceive performance measurement from a balanced scorecard (BSC) perspective.Design/methodology/approach – A survey designed from the four perspectives of the BSC framework is conducted on senior executives involved in the supply chain functions of client firms, and those executives from the logistics service provider industry.Findings – Despite the need to provide a balanced approach to performance measurement, firms remain focused on traditional financial measures (gross revenue, profit before tax, and cost reduction). From a supply chain perspective, the non‐tangible measures such as customer satisfaction are most measured. Other key logistics performance indicators include on‐time delivery, and customer satisfaction.Research limitations/implications – The findings are based on a sample size of 113. Thus, some respondent clusters are smaller than others. Hence, the results may not be r...

EOQ models with general demand and holding cost functions

Abstract We consider the continuous, deterministic, infinite horizon, single item inventory system, within the setting of a retail sector, in which the demand rate for an item is dependent on the existing inventory level. The traditional parameter of the replenishment cost is kept constant but the carrying cost per unit is allowed to vary. Two possibilities of variation are considered: (a) a non-linear function of the length of time the item is held in inventory and (b) a non-linear function of the amount of on-hand inventory. We find the optimal policies and decision rules and show that the classical EOQ model is obtained as a limiting case.

Logistics development in China

The accession of the Peoples Republic of China to the World Trade Organisation should provide greater access to an erstwhile‐untapped market. Trade and foreign investments are expected to increase rapidly. Under this setting, an enormous challenge is posed to the logistics industry as it endeavours to meet the increased demands of the market. Based on the secondary data, this paper finds that despite the improvements and advancements undertaken by the Government and other agencies, the current logistics infrastructure, particularly those of transportation networks, telecommunications systems, warehousing facilities and customs procedures are still lacking. Future developments are also highlighted to portray an accurate assessment of the logistics situation in China.

Discrete Time Model and Algorithms for Container Yard Crane Scheduling

Container terminal (CT) operations are often bottlenecked by slow YC (yard crane) movements. PM (prime mover) queues in front of the YCs are common. Hence, efficient YC scheduling to reduce the PM waiting time is critical in increasing a CTs throughput. We develop an efficient model for YC scheduling by taking into account realistic operational constraints such as inter-crane interference, fixed YC separation distances and simultaneous container storage/retrievals. Among them, only inter-crane interference has ever been considered in the literature. The model requires far fewer integer variables than the literature by using bi-index decision variables. We show how the model can be solved quickly using heuristics and rolling-horizon algorithm, yielding close to optimal solutions in seconds. The solution quality and solution time are both better than the literature even with additional constraints considered. The proposed formulations and algorithms can be extended to other problems with time windows and space constraints.

Impact of value chain activities on quality and innovation

Purpose – This paper aims to explore the extent to which four elements of the value chain – marketing, research and development, procurement, and operations – are associated with product quality and product innovation.Design/methodology/approach – A survey of 194 managers of Australian firms, and multivariate analysis using structural equation modeling was used to test the hypotheses.Findings – The elements of the value chain differ in their association with product outcomes. Marketing and production are related to product quality, but surprisingly while research and development is related to product innovation, marketing is not. Procurement is related to both product quality and product innovation.Research limitations/implications – The paper shows that individual elements of the value chain are related to specific competitive strategies and how these elements are related to each other, suggesting the need to direct effort within the firm for better, targeted performance. The results are limited by the s...

Development and simulation analysis of real-time yard crane control systems for seaport container transshipment terminals

As more and more container terminals open up all over the world, terminal operators are discovering that they must increase quay crane work rates to remain competitive. In this paper, we develop a real-time yard crane control system and show that a terminal’s long-run average quay crane rate depends on the portion of this system that dispatches yard cranes in the storage area in real time. Several real-time yard crane dispatching systems are evaluated by a fully-integrated, discrete event simulation model of a pure transshipment terminal that is designed to reproduce the multi-objective, stochastic, real-time environment at an RTGC-based, multiple-berth facility. Results indicate that yard cranes should prioritize the retrieval of containers from the stacks, rather than the storage of containers into stacks. Also, the yard crane dispatching system should not only consider the trucks already waiting for service in the yard, but also the trucks that are heading towards the yard. The experiments provide the first direct connection in the literature between real-time yard crane control systems and long-run performance at a seaport container terminal. We also make a qualitative comparison between rule-based and look-ahead yard crane dispatching schemes, and discuss deadlocking issues in detail.