Coordinating decisions by supply chain partners in a vendor-managed inventory relationship

We look into the linked decision making in the vendor-managed inventory (VMI) relationship. It is a supply chain management model, where the retailer decides the retail price while the vendor determines its capacity commitment. In this model, the retailer and the vendor should coordinate their decisions in order to maximize their individual profit or the total profit combining the two participants together. The vendor has to take into account the demand pattern throughout the product life cycle (PLC) when it decides its capacity commitment, which will affect its inventory management cost during the PLC, while the retailer should change the retail price over the PLC so as to maximize the revenues and minimize the inventory cost at the same time. Employing a system dynamics simulation approach based on differential game theory, which also takes into account the product characteristics such as the demand’s innovation and imitation effects, we analyze and confirm the dynamic coordination of key decision variables by the supply chain partners in the VMI relationship.     

Values of the balanced decision making between supply chain partners

Coordination between supply chain partners is critical to effective supply chain management. In this paper, we consider two cases of decision-making structure for a simple supply chain consisting of two players: the first case in which a supply chain partner dominates the decision-making process, and the other in which two players share the decision-making process equally. According to the literature, we know a priori that the balanced decision making forges a better (financial) outcome than the dominating case does. Therefore, our primary research objective is to analyze detailed dynamics of resource allocation and sources of the benefit of the balanced decision making. Our analysis indicates that the value of the balanced decision making arises from more effective resource utilization than the dominating case does: each of the cooperative partners knows how to optimize its resource utilization better than the other does.     

Manufacturing learning propensity in operations improvement

In this article, we present an exploratory research on manufacturing firms' choices of operations improvement strategies. We found that in the subject firms there was significant correlation between learning propensity espoused by managers and their choices of strategies for operations improvement. Relying on empirical data and information, we also identified three primary factors that influenced the process for the managers to form particular learning propensities: infrastructure in the firm, product mix, and top management. The empirical study, albeit bearing only exploratory results, enabled us to propose a tentative conclusion that as more managerial resources and managers' attention were devoted to a particular improvement strategy for which the managers formed a learning propensity, that “way of doing things” became more effective as the intentional experience and substantive investment compatible with the selected strategy accumulated. The enhanced effectiveness of that strategy reinforced the learning propensity, and the improvement process became more induced for the selected strategy. © 1998 John Wiley & Sons, Inc.     

Configuring a manufacturing firm's supply network with multiple suppliers

Consider a supply network consisting of a manufacturer and its suppliers. The manufacturer produces different types of products, using a common set of inputs (e.g., raw materials and/or component parts) from the suppliers: but, each product needs a different mix of these inputs. The manufacturer sells its finished products to the market at the end of the current decision horizon, facing an uncertain market demand. In situations where a manufacturer has outsourced its parts production to contract manufacturers, the contract manufacturer's capacity available for the given manufacturer in a particular time period may be limited by “capacity reservation” agreements made in advance. Thus, in making production mix decisions for the current planning horizon, the manufacturer has to take into account both its own and the component suppliers' capacity restrictions. We develop a mathematical model and an iterative algorithm that helps the manufacturer solve its supply configuration problem, that is, how much of each raw material and/or component part to order from which supplier, given capacity limits of suppliers as well as the manufacturer. The model takes into account such factors as market demand uncertainty, costs and product characteristics. We present an numerical example to illustrate the interacting effects among critical parameters in the model, and apply the model to a real-world case of a computer manufacturer.     

Firms’ integrating efforts to mitigate the tradeoff between controllability and flexibility

We consider three manufacturing capabilities: controllability, flexibility, and integrating capability. Controllability is a firm's ability to control its process to enhance efficiency and accuracy and to better meet specifications. Flexibility is a firm's ability to cope with uncertainty and variation, both internal and external. Integrating capability is a firm's ability to integrate and coordinate diverse functions and parts of its supply chain, embodied in overall operations effectiveness and new product innovation. We put forth two hypotheses. First, there is an inherent tradeoff between controllability and flexibility. Second, a firm's integrating effort across its supply chain enables it to overcome such a tradeoff, making it possible to improve both controllability and flexibility simultaneously. Using data from 193 manufacturing companies, we test our hypotheses. It turns out that the relationship between controllability and flexibility is convex-shaped, indicating there are two distinct regions: one in which the relationship is negative and the other, positive. Further, the firms in the positive relationship region make significantly more effort to integrate, that is to say coordinate and communicate, across their supply chains, implying that as the firm strives to integrate its supply chain functions, it can mitigate the tradeoff between controllability and flexibility to a considerable extent.     

Structural factors of NPD (new product development) team for manufacturability

We explore whether structural factors of NPD (new product development) team such as its physical co-location and team composition are still relevant and important in enhancing manufacturability as part of NPD performance in this highly virtualized coordination era as much as in the past before the Internet. We also examine how the analysis result is affected by the product’s innovativeness as well as other control variables like project duration and product type. In order to answer the research questions, we collected data on 127 projects of new product development at a global consumer electronics company. Based on our analysis, we conclude that whether the NPD members are physically co-located throughout the product development process and whether the team membership is balanced have profound implications for enhancing manufacturability.     

Voice activity detection and speaker localization using audiovisual cues

This paper proposes a multimodal approach to distinguish silence from speech situations, and to identify the location of the active speaker in the latter case. In our approach, a video camera is used to track the faces of the participants, and a microphone array is used to estimate the Sound Source Location (SSL) using the Steered Response Power with the phase transform (SRP-PHAT) method. The audiovisual cues are combined, and two competing Hidden Markov Models (HMMs) are used to detect silence or the presence of a person speaking. If speech is detected, the corresponding HMM also provides the spatio-temporally coherent location of the speaker. Experimental results show that incorporating the HMM improves the results over the unimodal SRP-PHAT, and the inclusion of video cues provides even further improvements.