B to B Electronic Commerce (EC) technology is now in progress and regarded as an information infrastructure for global business. As the number and diversity of EC participants grows at the agile environment, the complexity of purchasing from a vast and dynamic array of goods and services needs to be hidden from the end user. Putting the complexity into the EC system instead means providing flexible auction server for enabling commerce within different business units. Market mechanism could solve the product distribution problem in the auction server by allocating the scheduled resources according to market prices. In this paper, we propose a partnering mechanism for B to B EC with market-oriented programming that mediates amongst unspecified various companies in the trade, and demonstrate the applicability of the economic analysis to this framework after constructing a primitive EC server. The proposed mechanism facilitates sophisticated B to B EC, which conducts a Pareto optimal solution for all the participating business units in the coming agile era.

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The development of IT will lead to the integration of computers and networks, and IT will become more function oriented service and result in an indispensable part of the social infrastructure. This means that the critical point will shift from prioritizing “ownership of IS (Information Systems) before anything else” to “how IT will be utilized.” By reaching this technology level, Western origin non-discretion oriented management concept where IT is used as an enabler and IT-based business tools can be flexible enough to accommodate highly discretion oriented practices in Japanese organizations. In other words, IT can finally be utilized in a Japanese way. Taking account of the technological development trend, there is a need to take a macro look at the meaning of the concept of business models, something that has become viewed in the “micro” as patent-related issues. Under such trends, the greater freedom in business design the multipurpose use of IT functions is providing, the more critical a capability in the design of an elaborate business model is becoming.

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In most of Light Emitting Diode (LED) semiconductor fabricating line, AGVs (Automated Guided Vehicles) are used to transport the products between the facilities in order to ensure dust-free operation in the transportation systems. It has been demanded to realize the route planning system which speedily derives a feasible transportation route so that each AGV does not interfere with other AGVs. In this paper, we applied an agent-based optimization method for the route planning problems with multiple AGVs in LED fabricating bay in which the total transportation time is minimized. In the agent-based method, each AGV agent independently searches its candidate of route. The imitated pheromone is effectively used to generate the route which avoids the collision among AGVs. In order to evaluate the performance of the proposed method, the lower bound of the original problem is obtained by using the Lagrangian relaxation technique. The performances of the proposed method are evaluated by using the value of duality gap for a large scale problem. The effectiveness of the agent-based optimization method is demonstrated.

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In this paper we examine the issue of tool management in a Flexible Manufacturing System (FMS). A tool center storing all tools for jobs is introduced and all tools can be shared by the machining centers through tool change between the machining centers and the tool center. Two tool-change methods, “Augmented Magazine Method (AMM)” and “Magazine Carrier Method (MCM)”, are proposed and evaluated using the methods for the allocation of tools and jobs proposed in this study. A job in this study is defined as a sequence of processing operations and is thus processed by a single machining center. We propose a two-stage method to integrate tool planning and the allocation of tools and jobs. The method in the second stage for the allocation of tools and jobs is proposed on the basis of an auction method including a dispatching rule. For the tool planning with AMM at the first stage, we propose a greedy search method to decide the total number of tools. By simulation, we investigate the characteristics and effectiveness of the proposed two-stage method and the tool-change methods together with the effectiveness of several dispatching rules.

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This paper deals with a scheduling problem in a flexible job shop with multi-level job structures where end products are assembled from sub-assemblies or manufactured components. For such shops MRP (Material Requirement Planning) logic is frequently used to synchronize and pace the production activities for the required parts. However, in MRP, the planning of operational-level activities is left to short term scheduling. So, we need a good scheduling algorithm to generate feasible schedules taking into account shop floor characteristics and multi-level job structures used in MRP. In this paper, we present a GA (Genetic Algorithm) solution for this complex scheduling problem based on a new gene to reflect the machine assignment, operation sequences and the levels of the operations relative to final assembly operation. The relative operation level is the control parameter that paces the completion timing of the components belonging to the same branch in the multi-level job hierarchy. We compare the genetic algorithm with several dispatching rules in terms of total tardiness and the genetic algorithm shows outstanding performance for about forty modified standard job-shop problem instances.

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Advanced Planning and Scheduling (APS) has been widely recognized as a promising method for solving real production planning and scheduling problems. Based on the proposal of a real-time job shop scheduling mechanism under an APS environment, which adopts the Lagrangean relaxation method as the optimization logic, the present paper describes a feasibility study of this mechanism by evaluating its calculation speed and re-scheduling quality. Numerical experiments have been carried out for various models having different scales, as well as different densities and strengths of random events, such as the arrival of new jobs or changes to the due dates for existing jobs. The results of experiments show that the proposed scheduling mechanism has the potential to satisfy the real-time scheduling requirements, not only in terms of calculation speed and solution quality, but also with respect to predictability of the calculation load. Finally, an improvement to the Lagrangean relaxation method is proposed to improve re-scheduling quality.

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This paper addresses a multi-item multi-process dynamic lot size scheduling problem with general product structure and setup time. In this problem, there exist various heterogeneous decision features such as lot sizing, lot sequencing, dispatching, and so on. We present a near-optimal solution method, which we call a narrow sense Lagrangian decomposition coordination method of solving all decision features involved in this problem simultaneously without specifying or awaking to them one by one. First, splitting the planning horizon into very small time-slots, for any item on any machine at any timeslot we denote a state of processing by using a binary decision variable which takes a value of unity if it is processed, and else then zero. Second, dealing with the transition of the inventory state of each item and time transition of each setup explicitly, we formulate the problem into a multi-dimensional dynamic optimization problem with constraints. Third, paying attention to the existence of the interaction constraints, we decompose the whole problem into item-based sub problems that can be reformulated into dynamic programming of one dimension to dissolve the curse of dimensionality. At the aim of guaranteeing the decomposability, we formulate the problem by echelon inventory. The computational procedure consists of solving sub problems for given Lagrange multiplier values and of coordinating those values. Finally, we verify the presented method by using a numerical model.

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Due to diversified customer demands and global competition, scheduling has been increasingly notified as an important problem-solving in manufacturing. Since the scheduling is considered at stage close to the practical operation in production planning, flexibility and agility in decision making should be most important in real world applications. In addition, since the final goal of such scheduling has many attributes, and their relative importance is likely changed depending on the decision environment, it is of great significance to derive a flexible scheduling through plain multi-objective optimization method. To derive such a rational scheduling, in this paper, we have applied a novel multi-objective optimization named MOON^2R (MOON² of radial basis function) by incorporating with simulated annealing as a solution algorithm. Finally, illustrative examples are provided to outline and verify the effectiveness of the proposed method.

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The three-dimensional bin packing problem (3DBPP) is orthogonally to pack a given set of rectangular-shaped items into the minimum number of three-dimensional rectangular bins. It is formulated as a mixed integer program (MIP) that can solve small-sized instances to optimum. For large scale of instances, a composite algorithm, aimed at solving the 3DBPP with several practical constraints, is proposed and evaluated by the lower bound and the test instances available on website. It should be noted that although the computational tests are conducted for the 3DBPP with identical bins, the proposed approach is designed for a general case with heterogeneous bins.

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This paper describes a method for the calculation of confidence intervals of simulation throughputs and utilizations. The method is based on the delta method and uses only a single simulation, where the variation of the underlying means is used to determine the variation of the performance function by using the first derivative of the performance function. While the method has some limitations, it can be used frequently in practice. In addition, the method can also be used for short simulations or rare event applications, where methods based on batch means fail. This method can easily be implemented into existing simulation software.

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This paper provides a novel method for detecting production bottlenecks and the shifting of the production bottlenecks. All production systems are constrained by one or more bottlenecks. Improving the bottleneck will improve the whole production system. Yet, finding the bottleneck is no trivial task. Furthermore, the system may change over time or due to random events, and subsequently the bottleneck may shift from one machine to another machine. The presented active duration method determines the bottleneck based on the duration a machine is active without interruption. The method is very robust, easy to apply and able to detect the primary and secondary bottlenecks in a wide range of production systems. The method is demonstrated using different examples. The measurement of the likelihood of a machine being the bottleneck aids in the decision-making regarding the allocation of the available resources.

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Aiming at the elimination of tardy jobs in a job shop production schedule, an optimization-oriented simulation-based scheduling (OSBS) method incorporating capacity adjustment function is proposed. In order to determine the pertinent additional capacities and to control job allocations simultaneously the proposed method incorporates the parameter-space search improvement (PSSI) method into the scheduling procedure. In previous papers, we have introduced four parameters; two of them are used to control the upper limit to the additional capacity and the balance of the capacity distribution among machines, while the others are used to control the job allocation procedure. We found that a ‘direct' optimization procedure which uses the enumeration method produces a best solution with practical significance, but it takes too much computation time for practical use. In this paper, we propose a new method which adopts a pattern search method in the schedule generation procedure to obtain an approximate optimal solution. It is found that the computation time becomes short enough for a practical use. Moreover, the extension of the parameter domain yields an approximate optimal solution which is better than the best solution obtained by the ‘direct' optimization.

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This paper concerns with a scheduling method for painting (preceding) line with much longer production lead-time than assembly (subsequent) line. In general, production schedule of the painting line is made independently based on the forecasted job requirement at the assembly line. When the job requirement changes at the assembly line by virtue of the change of customer order, therefore, production balance is destroyed between the both lines. To avoid the tardiness caused by such unbalance, we need to have many inventories for the painting line. Such countermeasure is taken place in many companies actually. Thus, to avoid the tardiness while keeping small inventory, we propose a scheduling method that makes a Pseudo-Pull production possible for the painting line. We have evaluated the proposed method through computer simulations.

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This paper describes the experience of developing a production planning and scheduling system, which makes more than 1700 kinds of end products from more than 300 kinds of large plates stocked in the intermediate warehouse. This system was mostly achieved with Constraint Logic Programming. As our business environments having changed, we ware in urgent need of converting our production method to the pull-type from the push-type. With the push-type production method, we have to keep our finish products in stock for three to four months and refill the stock in 30 days. The features of our system: it solved the complex network problem of 38 patterns found in the whole production process from cutting to shipment in generic way. At the former process, it also solved an optimization of the setups problem in the two-phase batch-type production.

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Marine research vessels and their systems are major assets in the marine resources development. Since the running costs for the ship are very high, it is necessary to reduce the total cost by an efficient scheduling for operation and maintenance. To reduce project period and make it efficient, we applied TOC project management method that is a project management approach developed by Dr. Eli Goldratt. It challenges traditional approaches to project management. It will become the most important improvement in the project management since the development of PERT and critical path methodologies. As a case study, we presented the marine geology research project for the purpose of operations in addition to repair on the repairing dock projects for maintenance of vessels.

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Titanium and its alloys find wide application in many industries because of their excellent and unique combination of high strength-to-weight ratio and high resistance to corrosion. The machinability of titanium and its alloys is impaired by its high chemical reactivity, low modulus of elasticity and low thermal conductivity. A number of literatures on machining of titanium alloys with conventional tools and advanced cutting tool materials is reviewed. The results obtained from the study on high speed machining of Ti-6Al-4V alloys with cubic boron nitride (CBN), binderless cubic boron nitride (BCBN) and polycrystalline diamond (PCD) are also summarized.

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The flexion-extension motion of the head-neck complex (HNC) in the trunk horizontal (fore-and-aft) vibration was investigated. It was assumed that the motion of the HNC only occurs in mid-sagittal plane. An electro-hydraulic vibrator was used as a source of vibration. The input acceleration and HNC angular velocity were measured whereas the trunk of the seated subject was fixed to the seatback. Accordingly, the acceleration of the vibrator was considered to be equal to that of the trunk. Six subjects took part in the experiment. They were exposed to the random motion at a magnitude of 1.60ms^-2rms (root-mean-square) for 50 seconds. The coherence and frequency response function between the HNC angular velocity and the trunk horizontal acceleration were then obtained on 0.5Hz to 10Hz. Averaging the obtained transmissibilities allowed to represent an optimized frequency response corresponding to each of the subjects. It was found that the HNC behavior above 0.8Hz was quasi-linear with a dominant resonance frequency between 0.8Hz and 1.6Hz. The variabilities of the results within and between subjects were investigated. It was further concluded that linear models could describe the HNC so that their orders should be selected in accordance with the frequency response function of the system as well as the objectives of modeling.

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For free motions, vibration suppression of flexible manipulators has been one of the hottest research topics. However, for constrained motions, a little effort has been devoted for vibration suppression control. Using the dependency of elastic deflections of links on contact force under static conditions, vibrations for constrained planar two-link flexible manipulators have been suppressed successfully by controlling the contact force. However, for constrained spatial multi-link flexible manipulators, the vibrations cannot be suppressed by only controlling the contact force. So, the aim of this paper is to clarify the vibration mechanism of a constrained, multi-DOF, flexible manipulator and to devise the suppression method. We apply a concise hybrid position/force control scheme to control a flexible manipulator modeled by lumped-parameter modeling method. Finally, a comparison between simulation and experimental results is presented to show the performance of our method.

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This paper presents the applications of a new vibration wave suppression structure, the balanced-perpendicularly-guided structure (BPGS), to suspension system design. This structure can transfer vibration input into several branches of vibration waves in the perpendicular directions, in a way that the forces of those perpendicularly guided vibration waves are balanced with each other. The radial type, the ring type, and the multiple-ring BPGS suspension systems are introduced. The related dynamic equations are derived, and the frequency response and the transient response are conducted. The perpendicular branches of the BPGS can absorb a large portion of the vibration waves and diminish them by the internal friction. The multiple-ring BPGS system can provide more flexibility in frequency range selection for emphasis to further improve performance.

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This paper describes the sensitivity analysis algorithm extending the concept of the transfer stiffness coefficient method (TSCM) which is suitable to analyze accurately vibrations of complex and large structures on a personal computer with small computer memories. This sensitivity analysis algorithm is based on the concept transferring the sensitivities of the stiffness coefficient with respect to design parameters. In this paper, the free vibration analysis algorithm by the TSCM for a straight-line structure is shortly introduced and the free vibration sensitivity analysis algorithm is formulated by the present method. To demonstrate the validity of the present method, a straight-line beam structure with various boundary conditions is proposed as a numerical example. Eigenvalues and eigenvectors and their derivatives for the beam obtained by the present method are compared with those of the Fox's method and the reanalysis on a personal computer.

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Finite element (FE) model updating is an important tool to improve the accuracy of an initial FE model so that the predicted dynamic behavior matches as closely as possible that tested during the experiment. Two sets of new frequency response function (FRF) correlation functions, i. e. the amplitude correlation coefficient and the shape correlation coefficient are introduced, and an updating algorithm has been obtained by using the sensitivity of FRF correlation functions with respect to the selected design parameters. The use of physical parameters in model updating is implemented from a large ship model. The results indicate that this technique is feasible for very incomplete experimental FRF data and any updating frequency range, even in the case of measurement noise.

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On the basis of the dynamics equation of Jeffcott rotor-stator model with imbalance, the random responses of rotor-stator systems with rubbing is studied. The method is based on a second order expansion of the governing equations and the matrix calculus, the Kronecker algebra is used in the mathematical development. The random parameters including shaft stiffness and damping, stator stiffness and damping, radial clearance and stator radial stiffness are used to research the random responses of the rotor-stator systems. The numerical results are also presented and discussed.

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In this paper, the noise reduction performance of a new roadside barrier, which is called double screen barrier, is presented and studied theoretically and experimentally. The theoretical predictions are developed and based on Macdonald's diffraction theory. A case study of traffic noise mitigation is presented to show the effectiveness of the different barriers, including vertical barrier, cantilever barrier, double screen barrier, and partial enclosure. It has been found that the double screen barrier gives the best noise reduction performance among the four mitigation measures. A 1: 4 scale model of the proposed double screen barrier has been developed. The experimental results have good agreements with the predictions, provided that absorption material must be fully filled into the trough of the V-shape panel of the double screen barrier to reduce the sound reflection, and the gap width between the V-shape panel edges must be large when compared with the wavelengths of frequencies of interest.

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In this paper, a close-fitting enclosure model is used to prove the existence of a common structural-acoustic coupling experimentally, which deteriorates the insertion loss performance but was not considered in the formulas developed by Refs.(1)-(3) and the classical formula used in Refs.(4)-(6). The experimental results show that an enclosure, which first anti-symmetric structural and acoustic resonant frequencies do not coincide or nearly coincide, can avoid strong structural-acoustic couplings within the air cavity. At the acoustic resonance frequencies, the insertion loss performance of an enclosure can be improved by using the aluminum fiberboard, porous aluminum, and perforated aluminum panel to absorb the sound energy. Stiffener is useful to enhance the insertion loss ability of an enclosure if the dominant frequency bands of the noise are below the first structural resonant frequency. For having good damping effect to suppress the noise radiation at structural resonant frequencies, an enclosure should be mounted with both stiffeners and damping treatments.

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Multi-damped-oscillation control signals are applied in this study for active noise control (ANC) in an acoustic duct. Feedback active noise controllers that can generate damped-oscillation control signals are designed by using an internal model-based linear quadratic Gaussian (LQG) design technique. The low and upper bounds containing a desired ANC bandwidth is specified by two frequencies of the control signals. To acquire desired ANC performance, sound pressure attenuation ratios within the bandwidth are tuned by control signals of other frequencies and damping ratios. Computer simulation and experimental results show that sound pressure attenuation ratio of ≤ 0.3 and ≤ 0.5, respectively, can be achieved in a wide-band of 100Hz by using 3 damped-oscillation control signals. Experimental results also show effective noise reduction for time varying disturbance and band-limited white noise within the ANC bandwidth. These results support the feasibility of the designed controllers with damped-oscillation control signals for wide-band feedback active noise control in acoustic ducts.

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The variable displacement axial piston pump (VDAPP) is inherently nonlinear, time variant and subjected to load disturbance. The controls of flow and pressure of VDAPP are achieved by changing the swashplate angle. The swashplate actuators are controlled by an electro-hydraulic proportional valve (EHPV). It is reasonable for swashplate angle of a VDAPP to employ neural network based on adaptive control. In this study, the nonlinear model of the VDAPP with a three-way electro-hydraulic proportional valve is proposed, and a neural network model-following controller is designed to control the swashplate swivel angle. The time response for the swashplate angle is analyzed by simulation and experiment, and a favorable model-following characteristic is achieved. The proposed neural controller can conduct nonlinear control in VDAPP, enhance adaptability and robustness, and improve the performance of the control system.

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A car-following model has been proposed as a part of a microscopic traffic simulation model for the evaluation of automobile's control systems. The car-following model imitates human drivers' logic in the calculation of longitudinal acceleration rate. It has been designed to be consistent with a macroscopic traffic stream model that fits real world's traffic stream well. The model has parameters that should be different among drivers. We have applied a genetic algorithm to identify the model parameters from the data obtained from experiment on a driving simulator. The model with identified parameters produces speed profiles similar to those of human driver. We have verified by simulations that the model enables stable starting and stopping of traffic stream. The stability in the presence of hard disturbance has been also confirmed. The traffic streams simulated from the model have macroscopic flow parameters that are close to those of real world's traffic.

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This work presents the results from the controlling of the thermal environment of an enclosed space using Euler-Lagrange equations in a variable control problem, and compares it with three semi-empirical controller settings. Thermodynamic characteristics of the space of the administrative building equipped with convectors, disseminating heat energy supplied by steam, provided its mathematical model, which is fully commandable and observable. The model of the enclosed space-single-zone room-was reduced to the desired order dimension applied on the model's transfer function. Set in feedback control-loop with a PS controller, the indoor air temperature, heat fluxes as well as heat consumption over screened period were simulated under certain weather conditions and internal thermal loads, thus the thermodynamic responses of the space were obtained. Comparing the outputs with measurements and the results obtained for each simulation case showed energy savings and the optimal variable control method itself as an effective alternative, if Lagrange multipliers in Euler-Lagrange equations could be solved separately apart from model state-form variables. Further, maintaining Hamilton function as time-independent within defined boundaries, proves along with optimal control solution the readiness for its application in control algorithms of current heating systems.

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This study investigates thermal behavior of an occupied room exposed to winter weather conditions by means of quasi-steady-state model of the room. The space is not air-conditioned during the winter season, i. e. there is no humidity control and thermal performance of heaters maintains desired indoor air temperature. To obtain pure thermodynamic characteristics of the space, the model was set up and a series of tests was carried out in order to validate the mathematical model and find the thermal characteristics of the enclosure, which could be used directly for direct control techniques (DDC) if applied. The build-up model's method imposes boundary conditions onto room-faced surroundings walls and couples Fourier equations' thermal network employing modified Biot number. It also enables us to simulate an hourly energy use as well as heat flux calculus based on sub-hourly time steps. The model features a water equivalent content of the room, time-varying heat transfer coefficients, and boundary conditions onto surrounding walls, respectively. As a full dynamic method it accounts for thermal influence of outdoor climate conditions, occupancy use and other internal sources of thermal energy. The paper emphasizes selection of system boundaries and practical calculus of radiation heat exchanges without claiming shape factor algebra. The numerical results of temperature transient time responses obtained from mathematical model are well in accordance with those obtained from measurement in the actual room.

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Conventional hydraulic valve-controlled systems that incorporate positive displacement pumps and relief valves have a problem of low energy efficiency. The objective of the research is to implement parallel control of energy-saving control in an electro-hydraulic load-sensing system and velocity control in a hydraulic valve-controlled cylinder system to achieve both high velocity control accuracy and low input power simultaneously. The overall control system is a two-input two-output system. For that, the control strategy of self-organizing fuzzy sliding mode control (SOFSMC) is developed in this study to reduce the fuzzy rule number and to self-organize on-line the fuzzy rules. To compare the energy-saving performance, the velocity control is implemented under three different energy-saving control systems, such as load-sensing control system, constant supply pressure control system and conventional hydraulic system. The parallel control of the velocity control and energy-saving control by the SOFSMC is implemented experimentally.

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This paper presents a design methodology for MIMO output time delayed systems satisfying the mixed sensitivity specification. Nevertheless the procedure is on the basis of the state space approach, it provides a controller with tuneable parameters, which makes the technique useful for practical applications. The key features of the proposed method are its capability to handle multiple time delays and to allow the calculations to be performed as in the time delay free system case. A solution for output time delay unstable system is illustrated with a numerical example.

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For a linear system with mismatched disturbance, a robust sliding mode control, using output feedback only, is developed in this paper. Although the system has an uncertain term, a novel state estimator is used which, using only measured outputs, can asymptotically estimate the system states. A control law is then designed with respect to the estimated signals. In addition, based on the H_∞ theory, the designed sliding surface can achieve robust stabilization and guarantee disturbance attenuation during sliding mode. Finally, a numerical example is demonstrated for showing the applicability of the proposed scheme.

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This paper deals with the problem of delay-dependent exponential stability for a class of neutral systems with time delay and time varying parameter uncertainties. An LMI based stability criterion is proposed. Examples show that the results are less conservative than the existing ones.

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This paper proposes a method for designing high performance fuzzy controllers with a compact rule system. The method is mainly derived from flexible parameterized membership functions (FPMFs) and an intelligent genetic algorithm (IGA) which is superior to the traditional GAs in solving large parameter optimization problems. An FPMF consists of flexible trapezoidal fuzzy sets that the fuzzy set is encoded using five parameters. Furthermore, the membership functions and fuzzy rules are simultaneously determined by effectively encoding all the system parameters into chromosomes. Therefore, the optimal design of fuzzy controllers is formulated as a large parameter optimization problem, which can be effectively solved by IGA. The proposed method is demonstrated by two well-known problems, truck backing and cart centering problems. It is shown empirically that the performance of the proposed method is superior to those of existing methods in terms of the numbers of time steps and fuzzy rules.

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Uninterrupted power supply has become indispensable during the maintenance task of active electric power lines as a result of today's highly information-oriented society and increasing demand of electric utilities. The maintenance task has the risk of electric shock and the danger of falling from high place. Therefore it is necessary to realize an autonomous robot system using electro-hydraulic manipulator because hydraulic manipulators have the advantage of electric insulation. Meanwhile it is relatively difficult to realize autonomous assembly tasks particularly in the case of manipulating flexible objects such as electric lines. In this report, a discrete event control system is introduced for automatic assembly task of electric lines into sleeves as one of a typical task of active electric power lines. In the implementation of a discrete event control system, LVQNN (learning vector quantization neural network) is applied to the insertion task of electric lines to sleeves. In order to apply these proposed control system to the unknown environment, virtual learning data for LVQNN was generated by fuzzy inference. By the experimental results of two types of electric lines and sleeves, these proposed discrete event control and neural network learning algorithm are confirmed very effective to the insertion tasks of electric lines to sleeves as a typical task of active electric power maintenance tasks.

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In the planning of robots, the avoidance of humans working in the same work space, considering human emotions, was examined experimentally. We adopt the control law that the robot's evasive motion should follow the motion of an approaching human hand at a constant interval (referred to as the following distance). First, the relationship between human emotions and the motion parameters of robots (that is, the following distance and velocity of motion in the task direction) were experimentally clarified first using the rating scale method. The results show that appropriate combinations of motion parameters exist, and that the emotion “Pleasant” was representative of the emotions. Second, the control law of the robot's avoidance motion, in which the following distance is adjusted based on fuzzy inference with respect to the emotion “Pleasant”, was proposed. The effectiveness of the proposed method was experimentally confirmed using an existing two-degree-of-freedom robot.

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This research has been performed to estimate the hunting motion hysteresis of railway passenger cars. An old and a new car with almost the same structure are chosen for analysis models. To solve a set of simultaneous equations of motion that are strongly coupled with creep relations effectively, a shooting algorithm in which the nonlinear relations are regarded as a two-point boundary value problem is adopted. The bifurcation theory is applied to the dynamic analysis to distinguish the differences between linear and nonlinear critical speeds by variation of parameters. It is found that there are some factors and their operation area to make nonlinear critical speed respond to them more sensitively than linear critical speed. Full-scale roller rig tests are carried out for the validation of the numerical results. Finally, it is concluded that the wear of wheel profile and the stiffness discontinuities of wheelset suspension caused by deterioration have to be considered in the analysis to predict the hysteresis of critical speed precisely.

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This paper describes an experimental and theoretical study of the feasibility of using fiber reinforced to produce lightweight low-cost elastomeric isolator. The fiber in the fiber-reinforced isolator, in contrast to the steel in the conventional isolator is assumed to be flexible in extension. Several examples of isolators in the form of long strips were fabricated and tested. The theoretical analysis and test results suggest that it is possible to produce the fiber-reinforced strip isolator that matches the behavior of a steel-reinforced isolator. The fiber-reinforced isolator is significantly lighter and can be made by a much less labor-intensive manufacturing process.

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Analysis of contact interfaces represents one of the most critical engineering problems and involves a huge number of practical applications such as roller bearings, tooth gears, wheel-rail interaction, electrical and thermal couplings, biomechanics etc. While theoretical and numerical approaches to the problem have been extensively studied over the years, only a few experimental techniques have been devised either to validate analytical results, or to infer information non invasively about the state of contact. From the late 1950s onwards, when a relationship was discovered between the amount of energy reflected or transmitted through the contact region and the characteristics of contact, researchers have been employing ultrasonic waves to inspect contact interfaces. Since then, many efforts have been directed towards improving the experimental technique and enhancing the theoretical understanding of ultrasonic waves propagation over an incomplete contact interface. In the light of these considerations, the application of a simple ‘pulse-echo' technique able to investigate the elastoplastic contact of a steel sphere-plate system is proposed in this paper. The main purpose of the analysis is to assess the reliability of the ultrasonic method as a useful tool for assessing a number of contact parameters such as size and shape of contact area, distribution of contact pressure and so on. Experimental data were compared with numerical results obtained using a Finite Element Model (FEM) code. Ultrasonic reflection data were in good agreement with calculated values, thus confirming the effectiveness of the ultrasonic technique as a fast, reliable and non-invasive method in evaluating contact parameters in loaded metallic interfaces.

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The study proposes a new machining method to create an overhanging sharp corner. Sharp corners on overhanging surfaces are difficult to machine in conventional way or even in 3 to 5-axis EDM especially if the surfaces have different angles. This is due to the limitation of the feed direction and the structure of the electrode wherein it must be symmetrical with the target shape. In present research, we try to machine the sharp corner with overhanging surfaces using the new machining method. The 6-axis control machining is applied to set a non-rotational tool at an arbitrary position with arbitrary attitude against the workpiece. During cutting, the ultrasonic vibration is applied on the cutting edge of the tool, while the tool travels along the feed direction. As the cutting is performed, the 6 axes (X, Y, Z, A, B, and C) move simultaneously, depending on the tool attitude at a certain cutting point. From the experimental results, it is shown that the 6-axis control ultrasonic vibration cutting is capable of producing a sharp corner on overhanging surfaces.

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While the rough turning process is machining a workpiece at various cutting depth, the feedrate is usually selected based on the maximum depth of cut. Even if this selection can avoid power saturation or tool breakage, it is very conservative compared to the capacity of machine tools and can reduce the productivity significantly. Many adaptive control techniques have been reported that can adjust the feedrate to maintain the constant cutting force. However, these controllers are not very widely used in manufacturing industry because of the limitations in measuring the cutting force signals and selecting the appropriate cutting force level. In this paper, an unmanned turning process control system is proposed based on the spindle drive characteristics. A synthesized cutting force monitor is introduced to estimate the cutting force as accurately as a dynamometer does. The reference cutting force level as well as the feed-rate is selected considering the spindle motor characteristics. Because the cutting process is highly nonlinear, a fuzzy logic controller is applied to maintain the desired cutting force level. The experimental results demonstrate that the proposed system can be easily realized in CNC lathe with requiring little additional hardware.

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The possibilities for developing a new type of material processing using a microbiogenic function are investigated with a microbial corrosion test of metals under the sea. The behavior of microorganisms in the corrosion of metals (mild steel, copper and aluminum sheets) is examined, and their action on these metals is discussed. As a result, three processing methods (biomachining, biodeposition and biorecycling) are proposed and discussed.

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