This study proposes a method of visualizing and analyzing arguments that are discussed during decision-making processes concerning changes in business, in order to determine what problems exist and the causes of failures in the planning process. Firstly, the categories of classification used for analysis are presented by arranging the aspects of arguments discussed by participants in a business meeting. Next, data that has been accumulated using the business system transformation model (BSTM) is used to visualize the structure of discussions in terms of categorized aspects of arguments. This structure is plotted on two-dimensional scatter diagrams using multivariate analysis (quantification method Type-3). Then, using real business cases that are accumulated through the BSTM, this study proposes a way to analyze typical problems in the planning process using the structure of discussions that are plotted on the scatter diagrams. Finally, operational problems of this method and the possibilities of using this method as a way to encourage discussions in current business planning are discussed.

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Problems associated with document classification, an important application of text mining of text data, are focused on in this paper. There have been many models and algorithms proposed for text classification; one of these is a technique using a vector space model. In these methods, a digital document is represented as a point in the vector space which is constructed by morphological analysis and counting the frequency of each word in the document. In the vector space model, the documents can be classified using the distance measure between documents. However, there are specific characteristics in the vector space model for document classification. Firstly, it is not easy to automatically remove unnecessary words completely. The existence of unnecessary words is one of the characteristics of the text mining problems. Secondly, the dimensions of the word vector space are usually huge in comparison to the number of words appearing in a document. Although the frequencies of words appearing in a document could be small in many cases, many kinds of such words with small frequency can usually be used to classify the documents. In this paper, we evaluate the performance of document classification in the case where unnecessary words are included in the word set. Moreover, the performance of the distance measure between documents in a large dimensional word vector space is analyzed. From the asymptotic results about the distance measure, we can provide an explanation of the fact given in many experiments that classification using the empirical distance between documents calculated via the cosine measure is not particularly bad. It is also suggested that the KL-divergence is not useful for text mining problems.

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For many people, material handling is a daily task particularly associated with delivery. According to the delivery, variations are observed in the loads and process conditions. In particular, variations can be seen when materials are handled while ascending and descending staircases. Various measures to counter problems in material handling have been adopted. However, research on the physical stress associated with handling materials while ascending and descending staircases has not been performed. In this study, we used a biomechanical method to evaluate the physical stress caused by carrying a box up and down a staircase. In this experiment, ten healthy male subjects were asked to carry boxes up and down a staircase under four conditions. Two conditions depended on the way the box was held (i.e., use or non-use of handhold cutouts), and the other two depended on the size of the box (i.e., big or small). The dimensions of the mock staircase were as follows: 180-mm risers, 300-mm treads, and a staircase width of 900mm. The big and small boxes both had a weight of 15kg. We determined the evaluation indices for load on the body trunk, muscle activity, maximum torque ratio of each joint, and the low back spinal compression force. The results showed that the subjects lost their balance when carrying boxes up and down the staircase as compared to when carrying them along a flat floor. We found that there was considerable stress on the upper limbs when carrying the boxes up and down the staircase. Furthermore, the activity of the erector spinae muscle was found to increase in order to maintain the balance of the upper body. With regard to the relationship between physical stress and work conditions, the muscle load and torque of each joint decreased when the box was held using handhold cutouts.

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At retail stores, it is a common practice to maintain some inventory so that products can be sold to customers. If demand is more than expected and the inventory is insufficient, the retail store will ask the manufacturing plant to supply additional stock. Since it takes a certain lead time to deliver the additional inventory, it is necessary to make the customers wait for this length of time. The yield parameter is defined as the percentage of customers willing to wait. A newly developed product that is introduced to the market is in high demand for a short time. When the product fully prevails over market, demand for the product falls. Thus, the yield parameter of customers willing to wait for the product decreases throughout the lifecycle of the product. Applying the two parameters of stock cost and the willingness of customers to wait for a certain lead time, the production-sales profit is formulated based on the condition that the product demand in a unit period fluctuates in a probability distribution. Using the production-sales profit model, a transition from make-to-order to make-to-stock system is analyzed.

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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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