[in Japanese]

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This paper discusses a digital design and manufacturing system model for agile development and production. For the last few decades, virtual design tools for CAD/CAM, simulator and flexible production equipment such as 3D scanner, 3D printer, NC processing and assembly machine has been realized. Traditional manufacturing enterprises can not respond to changing personal demands and community demands while they can overproduce the commodities. Therefore new type of enterprise models is required. An open and agile model that is based on both iterative development method using time box for the project management and virtual manufacturing is proposed. First, the definitions for the frames are given then the four layer structure model is explained.

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In this paper, we consider a discrete design problem of two-dimensional truss structures. Given a set of potential nodes and a set of potential bars connecting these nodes, i.e., a ground structure, we only treat solutions which are combinations of accepted nodes and accepted bars in the ground structure. We present a linear inequality system with integrality constraints to extract a subgraph from the ground structure, which tries to model the subgraph on an extension of the simple truss. The linear inequality system delivers a MIP (Mixed Integer Programming) formulation. We also conduct numerical experiments to examine the solutions obtained by solving the MIP problem, and report the results.

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The present paper describes a basic research of modularization technology and robust design based on Taguchi Method. The modularization technology used in this paper is based on DSM (Design Structure Matrix). DSM represents the relationship between the product components. A designer can modularize a product according to the relationship linked by DSM. Taguchi Method enhances the robustness of a target system. Taguchi method calculates the S/N ratio of a system with the typical values of the target design parts. The robust design can be achieved by referencing the S/N ratio. In this paper, modularization technology and Taguchi method are applied to the parallel mechanism and realize the improvement of its function.

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Cutting down various losses by means of supply chain management, on one hand, increases efficiency of supply chains, but on the other hand, decreases their robustness. Nowadays, supply chains involve various risks such as natural disasters and system failures. It is, therefore, essential to evaluate the risks and to devise countermeasures as supply chain risk management (SCRM). However, manufactures can not necessarily identify the complete supply chain structure, and this interferes with the implementation of SCRM. This paper proposes a method to evaluate the cost effectiveness of the countermeasures against the risks of the parts based on the bill of material (BOM) without identifying the suppliers. The method is applied to hard disk drive manufacturing to verify its effectiveness.

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This paper reports a development of radio trip-sensor for labor safety. Radio trip-sensors are expected to prevent labor accidents such as collisions due to blind corner. Such devices are not in widespread use because they are not categorized clearly as safeguards yet. A pilot unit toward the practical use of the sensor introduces the notion of the trip-sensor. The unit can caution about hazardous trip with high repeatability. Specifications and performances of developed devices are described.

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A personal care robot has safety-related functions like as a wireless approach warning function or an emergency stop function. These functions have to keep safe in used environment. Some of these functions use wireless communication system. In this paper, we assessed safety of a function using wireless communication system by using a wireless approach system as a case study. We have examined safety of the system against electromagnetic propagation and electromagnetic interference as hazards. The system has not enough safety against both hazards. These hazards are common risk for safety-related functions using wireless communication system.

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Evacuation motion simulation using 3D kinematic digital human models (KDH) considering experimental verification assuming tsunami struck is addressed. Representative patient transportation motions have been experimentally investigated and effectively utilized for KDH data calibration of accurate evacuation simulations. The patient transportation speed as well as the intermittent halt time on flat ground is significantly affected by the load of the transporters. As for the stairway going-up evacuation, the transit speed decreases from pack-strap carry two-person arm carry and slightly wounded walking in order. Several evacuee motion primitives have been developed using KDH for stairway going-up simulation assuming the evacuation to a tsunami evacuation tower. The experimental result such as walking as well as the transportation speed was introduced into the evacuation simulation as calibration data. The simulation results show that the evacuation time is affected by the number of evacuees or the congestion due to the patient transportation. The developed simulation techniques can be effectively utilized for the planning of tsunami tower evacuation and related crowd behavior prediction.

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In sheet metal processing, the cutting layout for raw material is determined in order to reduce the waste of material. Every part is allocated as many as possible in a certain area. This layout problem is called a nesting. There are many studies for the nesting problem and they have contributed to the improvement of productivity. However, most studies considered only to reduce the waste of materials. Many parts of several products which have different due date are allocated in one sheet metal. Thus the layout affects the production efficiency. Therefore, the nesting should consider the following manufacturing processes for entire manufacturing efficiency. In this study, we propose a Genetic Algorithm based nesting method, which considers both the reduction of waste material and the tardiness. Finally, we verify the effectiveness of the proposed method through some computational experiments.

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In sheet metal processing, every part is cut from a sheet metal by punching process. Before punching process, layout of parts is decided through nesting. If the parts are arranged as compactly as possible into a sheet metal, the waste of raw materials can be reduced. Thus, nesting is essential for optimizing the layout of parts. However, if the nesting is executed without considering schedule of the following manufacturing processes, there cause various inefficiencies all over the processes. Therefore, nesting and scheduling should be considered simultaneously for the efficient manufacturing. Under such understanding, in this study, we propose an integrated method of nesting and scheduling, which refers to Bottom Left Algorithm and Genetic Algorithm, respectively. Finally, we verify the effectiveness of the proposed method through some computational experiments.

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We have already proposed a job shop scheduling method to meet due-dates and to minimize overtime as far as possible. The sequence of operations of jobs is determined using the mixture of genetic algorithm and priority rule. In this report, we evaluate the performance of the proposed method by comparing it with lower bounds solved using a Lagrangian relaxation method. Numerical experiments show that the performance of the proposed method depends on the scale of problem and resolution time.

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Multi-agent reinforcement learning have been applied to the autonomous distributed scheduling method in order to improve the objective functions of individual job agents and resource agents, in the previous researches. New distributed scheduling method is proposed to improve the sum of earliness and tardiness of all job agents by applying multi-agent reinforcement learning to resource agents, in this research. The resource agents learn the selection criteria of job agents for next machining operation based on the status of manufacturing systems. Some case studies have been carried out to verify the effectiveness of the proposed method.

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Cloud information tool becomes popular as an enterprise business application, so that the number of enterprises who use such easy tool has increased. On the other hand, it is difficult to develop an in-house production management system on Cloud, because such system needs to have high security protection. In this study, an application program interface to cooperate with in-house RDB is developed, which also connects to another API provided by well-known webserver system. As an experimental case study, the proposed system is implemented as an order management system in a small manufacturing enterprise (SME). The results show that the system effectively performs to share the estimation information of repair orders between sales parson and plant managers.

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In the assembly process of high-mix low-volume production line, the control system must be flexible and robust to adapt to changes in state of manufacturing line such as switching product types, stopping for a short time, and out of stock of parts. In this paper, we propose a multi-agent based control system of the assembly process. Proposed agents work with BOM and their behavior depends on BOM tree structure. And we show mechanism of the multi-agent based control system to work with limited resources. In addition, a simulation system is developed to verify behavior of agents in various status changes.

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In the manufacturing order management that deals with both designed components and repetitive components, hybriddecision making systems including MRP and other traditional methods are required. For those production systems which have push and pull controls can be managed using decoupling point definition and related strategies. Using Bill of Materials structure information, this paper formulizes two kinds of decoupling points, and models some definitions by clarifying itsexpressions and constraints. Finally, the paper shows some strategies for practical production management and addresses some remarks.

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In this study, a prediction method of the curvature and torsion of a coaxial cable, especially its shielding wires, is proposed. It seems that a shielding wire of a coaxial cable strain more highly than its core wire when the cable is bent. However, the core wire is actually broken by bending fatigue before the shielding wire even if they have the same rigidity. So, in this study, a phenomenon causing such fact is investigated. If the central axis of a wire is assumed to be twisted around a virtual cylindrical/torus surface, the shape of the wire can be described based on the second fundamental form of the surface in the differential geometry. Furthermore, the maximum principal strain, which is related to the life of the wire, can be estimated from its derived shape.

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Process planning plays an important role of a bridge between product design and manufacturing, and computer-aided process planning (CAPP) has been discussed for a long time. Recent diversified customers' needs have driven development of agile manufacturing which can adapt to various manufacturing situations. CAPP should be also discussed from this point of view, and a set of flexible process planning methods have been proposed. Unlike conventional methods, in these methods, all feasible process plans are once generated, and then the optimal plan is searched and extracted. Therefore, it is possible to quickly re-supply a new plan which is optimal for a new situation when situation change has occurred. However, these methods involve a large computational load, since the full-search approach is taken in searching the optimal plan. This paper discusses a method for decreasing the computational load. The search process of the optimal plan is formulated as a 0-1 integer programming problem, and is solved by an existing method. Case studies proved its effectiveness.

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We are researching haptic device with a single degree of freedom (DOF) to apply force feedback required for remote operation. In the field of assembly operations, motion of parts with only one or two DOFs is required simultaneously and force feedbacks to operators are used only for maintaining contacts and detecting collisions among parts. So we think that we can assemble parts using a haptic device with a small number of DOFs in this field. In this report, we propose a virtual axis system for remote controlled assembly operation and show its preliminary results.

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This paper describes a haptic device with a single degree of freedom (DOF) that can be used for remote controlled assembly in 6DOFs. Most haptic devices have 6 DOFs for higher sense of reality. However, for assembly operations, motion of parts with only one or two DOFs is required simultaneously and force feedbacks to operators are used only for maintaining contacts and detecting collisions among parts. This leads to a possibility of assembly operations using a haptic device with a small number of DOFs. For this purpose, we have proposed the concept of 'virtual plane' to separate DOFs that the user manipulates and the DOFs that the system controls. To evaluate this idea, we have designed and developed a mouse-type single DOF haptic device with a torque sensor. A remote controlled system is also proposed where the developed device is used to control a 6 DOFs manipulator.

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Machine tool production is dynamic and complex, then production plans in each department fluctuates heavily. In such a situation, it is difficult for the production management department to control machine tool production effectively because each of production plans cannot be synchronized properly. In addition, it is still not clear how a production plan is made and conducted at an actual production site because implicit knowledge and know-how are often applied. In this study, we try to analyze production at an actual production site by modeling production system and production planning based on an actual data of the machine tool company.

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Despite its popularity as an operation management paradigm, lean or JIT has been generally considered difficult to adopt. One of the reasons could be that clear understandings of JIT have not been achieved in general. This study attempts to clarify the essential properties of JIT activities and the relationships among them by employing Factory Physics framework and SysML.

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The main objective of this study is to design and develop the navigation system for Unmanned Grounded Vehicle (UGV) using the ultrasonic sensor and encoder. This study used the differential drive type mobile robot and the robot was equipped with five ultrasonic sensors, two units of DC geared motor with encoder and controller board. It was started with the enhancement of encoder and robot trajectory using UMBmark method. From this study, it was difficult to ensure that the motor speed has 100% efficiency by using this method. The study was also identified that UMBmark method failed to improve the motor speed as well. However, by using the CBmark method, the motor speed reading can be improved significantly. It's also enhanced the encoder reading while correcting the robot trajectory. The second model is used to enhance the ultrasonic sensor reading using Extended Hessian Normal Form Feature Prediction (EHNFP). This method managed to improve the ultrasonic sensor reading and extract the infinite plane. And, the last model is combined both sensors to perform localization system of the mobile robot using Extended Kalman Filter (EKP). It shows that the mobile robot can perform the basic task using localization system.

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This paper proposes the best method for controlling Automated Guided Vehicles on a single-track guideway with some sidetracks. In factories, Automated Guided Vehicles, or AGV, are operated in order to carry their products or materials. Although it is necessary to operate AGV anywhere in the factories, there are some limited spaces such as clean room or accessway. So we want to save the installation spaces for guideway in these situations. In this paper, we suggest to install a bidirectional single-track guideway where the sidetrack for passing each other was installed instead of traditional double-track guideway in order to save spaces for installation area with keeping transport efficiency and time across the track. And we clarify the knowledge about controlling AGV on the single-track guideway with high transport efficiency.

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The objective of this research is to propose an optimization method in order to balance work loads for engineers joining in multiple projects. Every project is planned carefully to give appropriate work load to all engineers who join in the project and execute tasks. Though, since every engineer can join in the multiple projects, as a result, some engineers may be forced excessive work load to achieve the scheduled project plan. Therefore the project manager has to modify the project plan according to the necessities. There are feasible solutions to release the engineers from the excessive work load. In this paper, we propose a method for extending the operating term. The operating term is provided to execute the substance process of the task, which in general has longer time than the processing time. Since the processing time is fixed, the extension of the operating term causes the reduction of the work load.

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This research proposes a new reactive scheduling method using co-evolutionary genetic algorithms for machining and assembly processes in a manufacturing system. Reactive scheduling is a technique of improving a disturbed initial production schedule due to some changes, such as delays of manufacturing processes, occurred in a manufacturing system. Co-evolutionary genetic algorithms are extended in this research to deal with the modification of production schedules including not only machining processes but also assembly processes. A prototype of reactive scheduling system is developed in order to verify the effectiveness of the proposed method through some computational experiments.

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Semiconductor device manufacturing business has shifted from high-volume low-variety production to Agile Manufacturing. However, because the operation of production lines is conventional, production losses have made. Therefore, we study for optimization of a lot progress schedule according to the delay in lot progress and the condition of production equipment. We propose a model which optimizes lot processing balance. The model is one in some methods, and it makes a production loss minimize. In order to realize it, we suggest the multi-agent system which applied the concept of Grouping.

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Cellular manufacturing systems are well known as flexible and reliable manufacturing systems for assembly processes. A suitable control method is required for the cellular manufacturing systems to keep the production capacity in the case where unforeseen changes, such as delay of assembly processes, occur during the progress of assembly processes. This research proposes a new method for dynamic production management in the cellular manufacturing systems. When delays of assembly processes occur in the cellular manufacturing systems, delayed production schedules are modified in real-time by changing initial task allocations for workers and loading sequences of the allocated tasks in order to minimize the maximum tardiness of products. The method also allocates various tasks for untrained workers in order to enhance workers' capabilities and productivities in the case where the cellular manufacturing systems still have enough production capacities for minimizing the maximum tardiness. A prototype of task reallocation and rescheduling system is developed to evaluate the effectiveness of the proposed method.

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Digital fabrication is a process that joins physical products (consists of atoms) with computational models (consists of bits) through the use of leading-edge technologies for self-distributed manufacturing system. Recently, as the enablers of this process, a number of machines/tools, softwares, and online/onsite communities have been developed. These technologies encourage individuals to become makers, and diversify the landscape of the manufacturing systems. In this paper, we discuss the effects of the digital fabrication on the manufacturing systems, from the contexts of personal/social fabrication, and entrepreneurship. This paper also provides a viewpoint toward constructing resource-circulating systems through the digital fabrication.

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3D printing is known as a method to construct 3 dimensional shapes by material addition layer by layer. The method has possibility to fabricate an electrical and mechanical product by a single process. This characteristic is favorable for personal fabrication. Additionally, it can fabricate the products with lower environmental load. In this paper, the characteristics of 3D printing and the product life cycle process are discussed. Especially, 3D printing with bio-degradable materials is considered. As a feasible personal fabrication schema with low environmental load, which is combined with module reuse process and disassembly process by users, is proposed.

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It is easy for laser forming to control power and laserfoming does not use a tool, so there is not wear of a tool. There are a lot of advantage in laser forming. But laser forming is not practical because of working difficulty. In this paper, I explain temperature distribution of SUS304 wire after laser forming to use result of simulation. In addition, I show a result of experimental data of laser forming that I irradiate laser two difficult point of the surface of SUS304 wire. I found variation of bending angle because of distance of two irradiation points.

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[in Japanese]

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Allowing a large amount of renewable energy sources, such as rooftop solar arrays and wind turbines, for residential homes requires energy storage devices, such as Pb and Li-ion batteries. However, the materials for those batteries, such as zinc, lead, lithium and other minor metals, are facing to deficiency in the coming 50 years. This paper presents a novel energy storage device for residential use using mechanical energy that we have proposed as Lifting Mass Mechanism (LMM) concept. The device hoists a mass to store energy as potential energy when surplus energy is produced. By contrast with storing energy, the device releases the hoisted mass to generate power corresponding to energy demands using adequate control algorithms based on real-time energy state monitoring. Thus, we have designed and fabricated a prototyping of that mechanism to clarify overall energy efficiency. The experimental result shows that generation efficiency was 2.1%.

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The lake water pollution is a problem in recent years. To elucidate the mechanism of water pollution, water quality monitoring is important. A measurement system for providing water quality information is required to elucidate mechanisms of water pollution. This system consists with a server and a lot of sensor nodes, computer devices. Sensor nodes collect water quality information and images of the water, the velocity of the flowing water, which can be measured by each sensor and a camera, a GPS on a device with Android OS. The server receives data from sensor nodes and provides water quality information as web pages. In this paper, a program for the server, which receives and provides data, and a program for the computer device, which shows water quality information to users, are proposed.

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Measuring home energy use data is significant for reducing energy consumption and impact on the environment. Given the development of information and communication technology, data are easily collected over ubiquitous integrated networks. Near field communication such as Bluetooth and ZigBee is widely used to monitor home energy consumption along with its applications of home energy management systems (HEMS). This paper describes a prototyping of an energy consumption monitoring module using the near field communication. The monitoring module measures voltage and current of arbitrary electric power sources such as solar arrays and wind turbines as well as home appliances, and is designed with water proof casing structure. It comprised of three layers: low-level and middle-level layers include 8 sets of voltage dividers and current sensors, and high-level layer includes a battery, an A/D converter, which has 16 A/D channels, and a Bluetooth board for wireless serial data transmission. We have validated its data conversion using a reduced-size house model and data transmission via Bluetooth connection.

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[in Japanese]

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Given a set I={i|i=1,2,...,n} of current n items (for example, n green peppers) with their weights w_i and priorities γ_i, the food packing problem asks to find a subset I'(⊆I) so that the total weight Σ_<i∈I'> w_i is no less than a specified target weight T for each package, and it is minimized as the primary objective, and further the total priority Σ_<i∈I'> γ_i is maximized as the second objective. The combinatorial optimization problem has been known to be NP-hard, while it can be solved exactly in O(nT) time if all the input data are assumed to be integral. In this paper, we design a heuristic algorithm for the problem by applying a data rounding technique to an O(nT) time dynamic programming procedure. We also conduct numerical experiments to examine the empirical performance.

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Robot assembly systems contain one or more flexible robots which can carry out a large number of operations, and can conduct flexible assemble processes. This paper proposes a simultaneous multi-objective design optimization method of component layout and job schedule for multi-robot cellular manufacturing systems. First, in this paper, a sequence-pair representation scheme is utilized to describe layout design candidates, which is able to avoid interference between assembly system components, and the use of dummy components is proposed to represent layout areas where components are sparse. In addition, job allocation to each robot is considered as one of the design variables using discrete values. Next, the design criteria for robot cellular manufacturing system layout designs are clarified, and objective functions are formulated. A multi-objective genetic algorithm is then used to obtain Pareto optimal solutions for the layout and schedule optimization problems.

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The cell manufacturing system of a labor concentration type is still in the important position of the manufacturing industry at this stage. Since an operator's skill is greatly related to productivity in labor concentration type cell productions, the operator's effective training is important. On the other hand, when operators learn and acquire the multi-skill tasks, the level of difficulty in their mastery depends on the contents of target operations, so a sufficient plan for training is required. In this study, the main objective is the rapid improvement of operator's skill. Therefore, after classifying operator's skills about all the operation tasks, we try to optimize the task allocation in training mode, and evaluate its validity quantitatively.

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In this paper, we propose a stability-oriented method for capacity requirements planning (CRP) in manufacturing systems. Stability means here an indicator of plan/schedule robustness associated with a deviation between planned and actual starting time of activities, and enhancing the stability of CRP can lead to increase the sustainability of manufacturing system. The proposed method is compared with some conventional methods. Through computational experiments, the effectiveness of the proposed method is demonstrated.

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Dynamic changes in manufacturing production sites make current production schedule infeasible and inaccurate. In these cases, some parts in plans consisting of production planning are changed to obtain the plans adapted to these changes. In this study, we refer to these parts as optionality in production planning. In related research about production planning, optionality is preliminary set. However, this fixed optionality may not be suitable for certain cases, such as the case of having different factories, products and so on. In this study, we have analyzed optionality in production planning so far. In this paper, we develop new replanning model based on the optionality.

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Custom-made hip implants can offer the best available solution for patients with femoral anatomical deformity associated with arthritis when application of standard implant would not be appropriate. Additive manufacturing (AM) techniques are ideal for fabricating custom made objects with intricate external and internal geometry. In the present work, a design and digital fabrication methodology of patient-specific hip implants using AM based on patient CT images data have been introduced. The proposed methodology comprises the integration of medical imaging, CAD, anatomical reverse engineering, virtual reality (VR) and additive manufacturing. The methodology increases the potential of customizing implants to improve the geometrical matching of implant and surrounding bone.

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Prosthetic joint is used for the treatment of rheumatism, etc. The prosthetic joints are used as auxiliary for lost function, and the correction of deformation and protection of abnormal tissues. Because prosthetist makes a prosthetic joint for a user individually, it is costly and time consuming. On the other hand, it is possible to fabricate the prosthetic joint suitable for the user by using a layered manufacturing method simply. In this study, we have fabricated a single-piece dynamic orthosis which has a movement mechanism by means of the layered manufacturing using multiple materials.

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In recent years, additive manufacturing with multi materials has been attracted attention because it makes possible to create products which have multiple functions. In this study, we considered to shape electrical circuits in mechanical chassis at a time in order to create products which have multiple functions and high environmental compatibility. A method and a 3D printing prototype system are developed for embedding electrical wirings in molding of product chassis by using Fused Deposition Modeling (FDM). In the present report, a part out of ABS resin and electrically-conductive gels is experimentally fabricated and evaluated.

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This research proposes a closed-loop supply chain model which represents not only traditional forward supply chains for the generation of products but also reverse supply chains for the reuse of used products. The proposed model consists of four model components, these are clients, manufacturers, suppliers, and remanufacturers. Remanufacturers receive used products from clients and provide reusable parts to manufacturers. These model components modify their production schedules and negotiate with each other in order to determine suitable prices and delivery times of ordered products. Remanufacturers send orders for used products to clients and stimulate discarding the products, in order to control the balance of demand and supply of reusable parts. A prototype of simulation system for closed-loop supply chains was developed to verify the effectiveness of the proposed closed-loop supply chain model.

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An evaluation system for the purpos e of calcul ating equivalent CO_2 emission an d machining cost is develope d based on activity-based model. This developed system can evaluate a machining process from an NC program, workpiece information and cutting tool information, and the n calculate accurate equivalent CO_2 emission and machining cost. Cutting conditi ons especially cutting speed of end mill operation are evaluated from the viewpoint of equivalent CO_2 emission and machining cost. Based on a tendency of the evaluated results, an adequate cutting condition is achieved to minimizing equivalent CO_2 emission and machining cost as much as possible.

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About the environmental preservation in environmental division craftsmanship, there are two sides of the comfortable environment in the life cycle and process of manufacture of a product. The problem in the case of studying how manufacturing environment accompanied by 3K is made into comfortable environment about the life cycle assessment of a product, ISO 9000, 14000, the PL Law, etc. is described. Furthermore, the problem on education is described also about the inverse design which took LCA and 3R into consideration also about the environmental design.

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