本研究では,ビジネスシステムの立案段階における諸問題や失敗の原因を発見するために,意思決定過程でなされる議論を可視化し,それらを分析する方法を提案する.最初にビジネスミーティングで発言される意見の性質を調べ,可視化に用いる性質のカテゴリ分類の方法を示す.次にBusiness System Transformation Model(BSTM)に蓄積されている議論を分析の対象にし,多変量解析の数量化3類によって,カテゴリ分類された意見の性質から議論の構造を布置図上に可視化できることを示す.さらにBSTMに蓄積された複数の事例を用いて,ビジネスシステムの立案過程における諸問題を,布置図上に表現された議論の構造から分析する方法を提案する.最後に提案する方法の運用上の問題点を議論するとともに,本研究の可能性として進行中の議論を活性化させるために使用する方法などを示す.

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近年,インターネットの普及により膨大なテキストデータからの知識発見を扱うテキストマイニングの技法が注目されている.本研究では,テキストマイニングが取り扱う問題の中でも,特に文書分類の問題を取り上げ,形態素解析後の単語の出現分布としてある確率モデルのクラスを仮定し,文書分類の性能,並びに分類に用いられる距離について漸近的な分析を行う.一般に,文書分類に不必要な単語の混入を完全に排除することは難しく,様々な重要単語の重み付け法などが提案されている.本論文で扱う最初の問題は,このような分類に不必要な単語が混入することが,文書分類に与える性能劣化の程度を把握することである.さらには,単語の出現頻度に基づく文書分類においては,個々の単語の生起頻度は少なく,多くの単語の頻度がゼロとなってしまうというスパースネスの問題がある.すなわち,このベクトル空間上で一つの文書を表す点は,ゼロを多くの要素に持つベクトルで表現される.しかし,「このような状況で,文書同士の距離による分類がある程度の分類性能を示すのは何故か」という疑問については依然として経験的な解釈が与えられているのみである.その理論的根拠を与えるため,本稿では,各要素の出現頻度を有限に保ったまま,次元数を無限大とする新たな漸近論の概念を導入することにより,スパースな文書ベクトル間の距離について解析的な性能を示す.

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本研究では,荷物を保持しながら階段の昇降動作を行い,その動作のバイオメカニカル解析を行うことで,荷物運搬作業時の階段昇降動作における作業者の身体負担特性を明らかにすることを目的とした.実験は,健常な男子大学生10名を対象として行った.実験条件は荷物のサイズ2条件,荷物の持ち方2条件とし,それらを組み合わせた各条件で階段の昇降動作を行ってもらった.身体負担の評価は,ロードセル,筋電図を用いて行った.また,作業中に撮影した動画よりバイオメカニカル解析を行い,各関節の最大トルク比およびL5/S1椎間板圧縮力の推定値を求めた.その結果,計測した各指標の関係から,階段昇降動作における身体負担特性が明らかとなった.

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ある製品が市場で発売された後,評判を得て次第に需要が高まる.その製品が市場に行き渡ると,次第に新鮮さを失って,需要が小さくなる.一つの製品の発売時から商品として寿命を終えるまでの一生の間に,顧客がその製品を購入する意欲の強さは大きい状態から小さい状態に変化する.そのため,この間に,収益が高い生産販売方式は,MTO型からMTS型に転移する.生産販売方式の両極であるMTO型とMTS型を表現するために本質的である在庫費用比と顧客の歩留り率の二量をパラメータとして用い,MTO型とMTS型を包含する広範な生産販売方式における生産販売利益を表す数理モデルを提示し,その数式を用いて,一つの製品の商品としての一生の間に,生産販売方式がMTO型からMTS型へ転移する機構を解明する.

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Nowadays, concepts such as "lean" and "six sigma," which originated from Japanese manufacturing practices, prevail all over the world as leading edge paradigms in operations management. Practices such as these drove Japan to the top of the IMD international competitiveness ranking around 1990, but Japan's ranking has since fallen and is recently only in the top 30. Based on an international cultural comparison using Hofstede's cultural scores, this article claims that these strengths and weaknesses may come from Japan's culture, in which there is high uncertainty avoidance for objects and time, and which is quite different from not only Western countries but also other Asian countries. This hypothesis is examined by citing our research results regarding cross-national comparisons of CS and SCM performance. Through these considerations, interpretation is provided regarding phenomena currently occurring in Japanese industry considered to be side-effects of high product quality, such as Galapagos and quality homeostasis. Finally, a proposal is made regarding how Japan can overcome the problem and create new quality concepts by taking advantage of its relativistic culture not fixed to a single ideology or religion.

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When determining the sequence of a mixed-model assembly line, the following two objectives are usually considered: (1) leveling the load (total assembly time) for each process within the assembly line, and (2) maintaining a constant rate of use of each part in the line. For the first objective, we usually determine the sequence that minimizes maximum work congestion. For the second objective, a sequence is selected in which the quantity used per hour (i.e. consumption speed) of each part in the mixed-model assembly line is kept as constant as possible. Some studies have considered these two objectives simultaneously. In this paper, from the standpoint of supply chain management (SCM), we propose a new sequencing method that considers not only the two aforementioned traditional objectives, but also a third objective, that is, shortening the delivery time to a dealer when the final products are delivered by car-carriers. We propose an approach utilizing a two-stage sequencing method. In Stage 1, to maintain a constant rate of parts usage and meet the date of delivery, we divide the production period into shorter periods, and determine the production volume of each product for each period. Next, in Stage 2, we establish a production schedule for each divided period that realizes smoother production in the assembly line. We display numerical examples to explain and clarify the effectiveness of the proposed sequencing procedure.

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This paper presents a methodology for achieving effective coordination among supply chain parties in situations where the manufacturer makes various products based on orders received from an unspecified number of customers. The customers usually wish to obtain their products as early as possible or to set their due dates unilaterally. Naturally the manufacturer's workload varies over time and sometimes greatly exceeds its production capacity when many customers' orders coincide. It is clear that manufacturing costs can undergo extraordinary increases, raising product prices when the manufacturer changes its production capacity according to the customers' demands. The sole acceptable solution for both the customers and the manufacturer is coordination among all parties through information sharing, which will lead them to decide on appropriate due dates based on the overall benefit. The present paper proposes the concept of ideal manufacturer due dates that are estimated by considering all ongoing customer orders and shop status predictions, while still essentially guaranteeing fulfillment. We also present a methodology for quantifying the losses a supply chain can suffer due to customers' unilateral actions. Finally, a method is discussed in which customers are motivated to select due dates close to the ideal manufacturer due dates, taking into consideration product price increments that may result from choosing particular due dates.

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Global warming is a serious problem. As a signatory to the 1997 Kyoto protocol, Japan agreed to a 6% reduction of CO_2 emissions relative to 1990 levels. Since then, Japan has strived to achieve this target, but the recent situation in Japan is far from satisfactory; in fact an increase of 8% is predicted. In order to keep its agreement, the Japanese government and many companies are continuing their hard work. In this paper, we focus on the logistics field. First, we report on and discuss the situation and some problems in Japan in this field relating to reducing environmental impact, especially CO_2 emissions. In order to further reduce the CO_2 emissions, we propose a construction of a new paradigm that considers both economic and environment aspects and one that is acceptable to consumers. For this purpose, it is crucial to show the environmental impact, such as CO_2 emissions clearly and accurately. For example, the "carbon foot print" system is currently promoted in Japan and globally. However, the database is inadequate and the calculation methods for CO_2 emissions are no longer relevant right now. Therefore, an appropriate measurement method to obtain accurate data for CO_2 emissions is essential. In addition, a fair allocation system is even more essential. If possible, it is more desirable to adopt a calculation system for CO_2 emissions same as to "Activity Based Costing system". In the logistics field, this problem is outstanding, the calculation and allocation of CO_2 caused by transport and/or delivery activities are made practically by the tonnage-kilometre (ton-km) method. In this paper, we focus on the logistics field. Logistics is a very important and basic field that relates to all companies, consumers and citizens in every society. As well as science and technology, a sociological approach should play an important part in reducing the environmental impact in this field First, we discuss the recent situation regarding environmental problems in logistics. Next, we arrange the efforts of the reduction of the environmental load by the government and companies. Thirdly, we propose a new paradigm for the logistics-consumption relationship. In order to actualize this paradigm, we then propose a new method for measuring CO_2 emissions by transportation and delivery activities and allocating them to each piece of cargo or owner of cargo. And by experiment, we show the validity of this system. Finally, we discuss directions in the near future and what the society should look like.

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This paper describes the characteristics of motion performed with a high or low period by skilled subjects using three-dimensional coordinates and Tait-Bryan angles (yaw, pitch, roll). Different types of motion (filing a surface of iron workpiece or turning a nut) were analyzed and measurements were taken at different points on the human body. Despite these differences, it was found that humans skilled in a particular motion performed highly repetitive motion with same period (4.2Hz) in some axes and rotational angles. Furthermore, as cross-correlation analysis showed, a human even more skilled in a particular work performed a low-repetition motions with high similarity in some axes of three-dimensional coordinates. However, these motions did not show high similarity for Tait-Bryan angles due to the rotational angle of some motions having different patterns. We will continue to study skilled motion more to increase the reliability of proposed characteristics of motion using developed apparatus.

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With the recent progress in information technology systems equipping with ubiquitous computing technology, it has become feasible to manage objects in real space on an individual item level, in real time, across more locations than before. In this study, we refer to this information with high granularity as fine granular information, and the management that utilizes this information as fine granularity management (FGM). This study proposes an inventory redistribution process that is enabled by FGM and evaluates the operational impact of this process. This proposed process premises dynamic item allocation and solves inefficiency in the supply chain management (SCM) of short lifecycle items. The problem we deal with is a single period stochastic inventory management problem that retailers with multiple stores face, and future demand and amount of items for redistribution are computed using the proposed algorithm. We evaluate our proposal using SCM operation data disclosed by a real-life specialty store company and show the effectiveness of our proposal.

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Announcement effects of Seasoned Equity Offerings (SEOs) are a concern of researchers in empirical finance. In the US market many papers report a strong price decline after SEO announcements. Contrary to the US market, a slight price run up after SEO announcements has been reported in the Tokyo market, but these results have a limitation on the number of sample. In this paper we study the announcement effect of SEO firms listed on the 1st section of the Tokyo Stock Exchange based on more than one thousand SEO events. In contrast to the conventional researches, we found negative announcement effects similar to the US market after 2000. Motivated by these results, we conjecture that the Japanese institutional reforms in 2001 caused these negative announcement effects. We think the institutional regulations used to distort the price distribution. We analyze the effect by the option pricing model.

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The multilevel lot-sizing (MLLS) problem is a key production planning problem in the material requirement planning (MRP) system. The MLLS problem deals with determining the production lot sizes of various items appearing in the product structure over a given finite planning horizon to minimize the production cost, inventory carrying cost, backordering cost, etc. In a previous study, a particle swarm optimization (PSO) algorithm integrated with flexible inertial weight (WPSO-MLLS) was proposed for uncapacitated MLLS problems by embedding the characteristics of the MLLS problem, a coding system and redefinitions of operators for 'velocity' plus 'velocity', 'position' plus 'velocity', and 'position' subtract 'position'. This research further investigates the suitability of WPSO-MLLS by comparing the solving performance of WPSO-MLLS with a PSO algorithm without inertial weight (PSO-MLLS) and two extended hybrid versions of PSO, which are WPSO-MLLS integrated with crossover and mutation operators of a genetic algorithm (GA) (HWPSO-MLLS) and PSO-MLLS integrated with crossover and mutation operators of GA (HPSO-MLLS). Some benchmarking testing instances are adopted to compare these PSO algorithms.

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The milk-run model, which features of small-lot, high-frequency delivery according to fixed schedules, is an efficient way to support the Just-in-time (JIT) production strategy in the automotive industry. It influences the whole supply chain in view of the three-party relationship tied by information technology, and reduces transportation and inventory costs. In this paper, by analyzing the milk-run model of an automobile manufacturing company, its contribution to the supply chain is displayed. Using a space-dividing method entitled "integral slice algorithm," the container capacity during a milk-run is considered. Moreover, for the purpose of improving productivity, we optimize the company's milk-run model studied in this case.

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