This paper discusses with the integration of order bidding and manufacturing planning decisions that is, considering contingent orders and multiple production resources. The main objective of this research is to integrate decisions in the internal supply chain of a make-to-order (MTO) manufacturer. Our paper is positioned as subsequent research to Cakravastia et al. (2002), Cakravastia and Nakamura (2002) and Cakravastia and Takahashi (2002), which previously addressed the integration of manufacturing and procurement activities. In this paper, we focuson marketing and manufacturing integration. Since an order for an MTO manufacturer usually comes from a winning bid, we propose a model and technique to simultaneously determine the price and lead-time bidding decision for a new order. We take contingent orders into consideration because these orders, with some degree of probability, will arrive at the shop floor, causing workloads to rise at various facilities; thus affecting production control, scheduling, and hence cost. We extend the bidding decision model of Easton and Moodie (1999) for the case of multiple resources and multiple jobs for each order. As the fundamental objective of a bid is to provide profit to the manufacturer, instead of just winning the order, we integrate the bidding decision with the manufacturing planning decision in preparing the bid for a new order. This decision is responsible for defining : (i) job schedule, and (ii) fabrication lot size. By this integration, the consequences of each possible backlog scenario for manufacturing activities can be determined. The result shows that the proposed technique can be used to optimize the bidding decision and avoid over optimistic bids that would lead to the "winner curse" phenomenon.

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This paper discusses and proposes a systematized product development process based on an idea that product life is made of six structurally very similar engineering effort sub-cycles. The new product development process is a major part of multiple sub-cycles within the total product life. The development program starts from the initial idea stage and extends to the ending stage at the discontinuation of product support. At the early stage of this study, the original task node diagram was viewed as a large network diagram of approximately 1,000 nodes requiring the equivalent of 30 feet of connected letter-size paper. For the purpose of illustration, this continuous paper was coiled on to a spiral surface with the proper diameter to line-up the starting points of six sub-cycles, namely : Idea, Breadboard, Prototype, Pre-production, Manufacturing and Product maintenance. In many cases of product development, contract programs may cover only two to three sub-cycles each, such as the Bread-board, Prototype and Pre-production sub-cycles. Each of these six sub-cycles resembles one another with a nearly similar pattern. In general, the total of the smallest task stages observed within one sub-cycle was 18. Three task stages were grouped together to make six groups in one cycle. On one sheet of 8 1/2×11-in. paper, these three stages were shown together. Six pages hold one sub-cycle, and a total of six sub-cycles covers a complete product lifecycle totaling 36 sheets. In this proposal, several applications and evaluations of the concept are discussed. The discussions include : Node diagrams to serve as program status reporting media, progress control indicator, inter-departmental communication tool, accurate budgeting and cost estimating tool, and program control tool for multiple parallel product development operations.

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故障を考慮した多工程生産ラインにおいて, 単位時間当たりの平均総費用を最小化する最適発注・生産政策を求める問題を時間平均マルコフ決定過程として定式化する.しかし, マルコフ決定過程は工程数の増大と伴に次元の呪いを引き起こし, 事実上解くことができない.そこで, 大規模問題を解く近似手法として近年研究が進められている強化学習ともよばれている, ニューロ・ダイナミックプログラミングを適用する.本論文では, 修正政策反復法の値決定ルーチンにシミュレーションを用いるアルゴリズムSBMPIMを新たに提案し, 数値実験により厳密解ならびに既存のアルゴリズムとの比較を行う.さらに, 最適かんばん枚数を用いたJIT生産ラインにおける平均費用と比較し, 最適制御による効果を明らかにする.これらの結果, SBMPIM以外の既存のアルゴリズムであるSMART, SBPIは収束せず, またJIT生産ラインはSBMPIMによる平均総費用を7%以上増加させることが示された.

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本研究では既存の資源制約付きプロジェクトスケジューリング問題の解法SLA^*(search and learning A^* algorithm)を改良した新しい解法を提案した.主な改良点は, 資源利用率および並行作業数を次の作業を選択する時の評価基準として追加したことであり, 従来のSLA^*の評価基準であるプロジェクト遂行時間の見積もりに加えて3つの評価基準を重み係数により統合した複合評価基準を後続作業の選択基準とした.提案方法については異なる問題に対して行った数値実験で評価を行った.異なる問題は問題規模, ネットワーク複雑さ, 資源占有率および資源希育度により特徴付け, 問題を区別した.数値実験の結果, 提案方法は従来のSLA^*解法に比べて最適解を保持するか微小の犠牲のもとでバックトラッキング回数を50%以上削減することができた.

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本論文では, 一般的な分布に従う製品需要を持つ離散時間受注生産在庫システムの性能評価を行う.まず本システムの定式化を行う.次に本システムの安定条件を示し, 平衡状態における受注残の確率母関数を導く.さらに, 需要分布, 生産能力, 部品の納入リードタイム, 部品在庫の補充点が与えられたとき, 1期間当たりの平均総費用, 注文の平均遅れ等を求める.これらの結果を用い部品在庫の最適補充点を決定するアルゴリズムを導き, 数値例を示す.

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This paper proposes the development of a software simulator that allows users to build a supply chain model and analyze the logistics issues behind the model. The simulator consists of five kinds of participants and an e-marketplace for the supply chain. Each participant is implemented as a distributed object such that it runs concurrently and has the following capacities and policies : (1) end customers, (2) intermediaries including manufacturers, (3) parts suppliers, (4) electronic payment service providers, and (5) transportation servers. The e-marketplace defines the trade protocol for the workflow management and transaction analysis. The SCM simulator visualizes goods flow, money flow and information flow. This paper discusses the background of the proposal, the goal of simulator, and milestone, and technical issues for development.

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A job consists of several processes, and the job process line describes the job process content, orders and paths. If these are improved, productivity is expected to increase. The process analysis method (PAM) concept is introduced in this paper. PAM uses spreadsheet software to improve job processes and support job implementation. PAM users input job process data, which is mainly recorded upon the execution of each job process. Data such as date and time of process execution, time required, code number of the person in charge, etc. is recorded. As a result, PAM users can analyze and evaluate the data, and redesign the job process and flow. Furthermore, the redesigned job process data is input and analyzed. This effort results in alternative redesign plans. In the latter half of this paper, the daily job execution support system on the spreadsheet for the staff in charge and manager is discussed. For the PAM method, the processes flow line is designed using an Excel spreadsheet. One process (activity) is described as a square box consisting of nine cells. In each cell of a process, various information for that particular process is provided. From the data on each process and the flow chart input into the sheet, a business process chart is automatically drafted by an Excel's Visual Basic Application program we developed. This system can be utilized with popular spreadsheet software; therefore, anyone who has the spreadsheet on their personal computer can be offered the PAM utility. This system intends to support both redesign work and work process execution.

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