The number of pallets circulating in a closed loop production system is an important factor which affects the production rate. If the number is large, pallets stagnate in the system. If the number is small, an idling state occurs frequently in many stages. In both cases the production rate drops. Therefore, it is necessary to control the number of in-process pallets in the system according to the states of flow and stages in order to maximize the production rate. In this paper, we study the effect of input control for a closed loop production system with constant operation cycle time and stage breakdown. First, we model a flow in the system by a Markov model, and analyze the maximum production rate yielded in the system and the optimum policy for input control by a Markov decision process. Next, we present the effectiveness of input control comparing with the uncontrolled system. Finally, in order to investigate the effect of the number of pallets on the production rate, we analyze the production rate and the number of in-process pallets under the optimum policy using the reward function which consists of the production rate and the number of in-process pallets. The main results are as follows. (1) There is the optimum policy for input control which yields the maximum production rate. (2) The control is effective to increase the production rate and decrease the number of in-process pallets. (3) The decrease of the number of pallets monotonously reduces the production rate. However, if the buffer capacity is large, the reduction is very small near the maximum production rate.

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We propose a robotic forklift system for stacking multiple mesh pallets. The stacking of mesh pallets is an essential task for the shipping and storage of loads. However, stacking, the placement of

feet on edges, is a complex problem owing to the small sizes of the feet and edges, leading to a complexity in the detection and the need for high accuracy in adjusting the pallets. To detect the pallets accurately, we utilize multiple RGB-D (RGB Depth) cameras that produce dense depth data under the limitations of the sensor position. However, the depth data contain noise. Hence, we implement a region growing-based algorithm to extract the feet and edges without removing them. In addition, we design the control law based on path following control for the forklift to adjust the position and orientation of two pallets. To evaluate the performance of the proposed system, we conducted an experiment assuming a real task. The experimental results demonstrated that the proposed system can achieve a stacking operation with a real forklift and mesh pallets.

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In Japan, the aging and depopulation of its workforce are issues. Therefore, the development of autonomous agricultural robots is required for saving manpower and labor. In this paper, we described an autonomous

handling system for forklift, which can automatically unload and convey pallets for harvesting vegetables outdoors. Because of inserting the forks into a narrow hole, accurate posture estimation and accurate control of a forklift and the forks are required. The system can detect the by deep learning based object detection from an image. Based on the results of object detection and measurement by horizontal 3D light detection and ranging (LiDAR), the system accurately estimates a distance as well as horizontal and vertical deviation between the forklift and the in the outside field. The forklift is controlled by sliding mode control (SMC) which is robust to disturbances. Furthermore, the vertical LiDAR scans the for precisely adjusting the height of the fork. The system requires the environment with no or little preparation for the automation process. We confirmed the effectiveness of the system through an experiment. The experiment is assumed that the forklift unloads the from the vehicle as the real task of agriculture. The experimental results indicated the suitability of the system in real agricultural environments.

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Recently, various issues in self-propelled multi-storey car parks are becoming social concerns: accidents thefts, difficulty in finding a parking space, limited space for getting in/out of cars, and less friendly environment for novice/elderly users. These issues can be solved by introducing a valet parking system where car parking staff receives a car key from a user and drive the car to the parking space. However, the operator of the parking system needs to employ these staff, which impacts negatively financially. This paper aims to solve these conflicting demands by proposing an automated valet parking system by incorporating automatic pallets, which are mobile parking spaces. An automatic is an equipment dedicated specifically for transferring a car: it enables automatic entrance and exit procedures. The proposed system requires no human intervention and enables complete automated parking procedures.

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In this paper, the size which is used in a Container Freight Station (CFS) has been studied, in order to realize the effective cargo handling in a CFS. We have carried out general consideration based on the results of numerical analysis and experimentation. Suitabilities of size for container size, cargo size on a for container size, size for the area of CFS and size for fieldwork have been considered. Type T11 (1100×1100) and type T8 (1100×800) are suitable for the intermodal transportation, from the view point of utilization efficiency of container floor. 4 kinds of size, 1400×1100, 1200×1000, T11 and 1800×1200 (used in a CFS) are suitable for fieldwork in a CFS. Synthesizing the results of each suitability, it is advisable to use T11 in a CFS.

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The H-II Transfer Vehicle (HTV) is an unmanned transfer vehicle launched by an H-IIB rocket. It will support the International Space Station (ISS) program alongside the space shuttle, Soyuz, Progress, and ATV. JAXA is conducting pre-launch operations of the first HTV with its cargo at Tanegashima Space Center now and preparing its Control Center at Tsukuba Space Center. It is the final phase of 10 years of HTV development. This paper presents the development status and operation preparation for the HTV Launch in September 2009, then mentions future missions built upon HTV technical heritage.

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Multi-story car parking systems were invented to increase the capacity of car park buildings. However, it is pointed out that the systems have problems such as accidents (in-park movement, theft), searching for parking spaces, boarding/deboarding at narrow designated places, and difficulties in using for beginners and elderly people. To solve these issues, the authors of this paper propose to introduce electric pallets that are called automatic pallets for transporting vehicles and realize automated valet parking that automates procedures for entrance and exit. With the introduction of automatic pallets, a wide variety of vehicles can fit into specific configurations. This facilitates automation. Also, the authors propose a system for improving the time efficiency of exit operations. The time efficiency of automatic exiting is improved by automatically repeating movement to approach the exit side elevator after entering. However, it is unclear how good the time efficient exit operation in that system is. Also, the authors decided to simulate the proposed auto valet parking to find out what kind of problems there are. A simulation was performed on the entering reception and the exit operation. In addition, although random numbers are used in the simulation, two random number generation methods were used for comparison.

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The load composed of carton boxes takes various stabilizers on distribution. The vibration tests can be taken as the way of evaluating the effect of the load stabilizers. However, no confirming test protocols of the load stabilizing efficiency have been existed, because non-determinative motions are happened on the each box even if in the sinusoidal vibrating condition. First of all, the new reliability rate of the load stability is proposed. The indoor falling down vibration tests of the load strapped by the reusable belts are carried out to identify stabilizing effect. And the mathematical model by the distinct element method is produced to calculate the movement of the load falling down in vibration. Some basic vibration tests using the stacking blocks are also carried out to confirm the mathematical model.

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廃棄された木製パレットを原料として配向性ストランドボード（OSB）を製造した。パレットをシュレッダーで破砕後，リングフレーカーを用いて小型のストランドを製造した。それを10 mmのメッシュのスクリーンでふるい，繊維方向に長いストランドを分離した。これを原料としてOSBを製造した。目標ボード密度が0.70g/cm³のOSBでは，配向方向の曲げ強さは約65 MPa，直交方向のそれは約31MPaとなった。配向させることにより曲げ強さが向上した。剥離強さも約1.0MPaとなった。釘側面抵抗は約3.5kN，釘頭貫通抵抗も約2.5kNとなった。これらの強度的な性能は一般的なOSBよりも高い。メラミン樹脂を結合剤として使用したが，厚さ膨張率は約22％となった。相対湿度を0から90％へ変化させたときの線膨張率は0.24％となった。一般的なOSBと同程度の厚さ膨張率および線膨張率が得られた。

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A holonic fixturing system : HOLOFIX, to autonomously and cooperatively execute fixturing works of a workpiece is described and evaluated in this paper. HOLOFIX is developed by applying the concept of a holonic manufacturing system : HMS. All of elements in the system are holons, which comprise a black board and sub-holons and composed of a hierarchical structure : a holarchy. A holon can carry out tasks with other holons in autonomous and cooperative works. The effectiveness of a holonic system is clarified by experiments with a developed test bed of HOLOFIX; the black board communication system realizes autonomous and cooperative works between holons, and a workpiece is fixed on a without giving sequential tasks like a program.

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This paper describes a robot equipped with a computerized tactile member named “HI-T-HAND”that can feel the forms of various objects and their positions and, according to the command, pack the objects compactly one by one into a given .
The major functions of the robot are to, (1) feel for scattered objects, (2) recognize the form and the position of an object for holding it firmly, (3) change the posture of an object to facilitate subsequent operations, (4) select the best methods of shifting an object toward and positioning it in a and, (5) push an object, for tight packaging, against the inner wall of a or against other objects already thus arranged.

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The objectives of this study were to develop an automatic tray-discharging system for rice seedlings that can automatically carry germinated trays from pallets to conveyors whereby they are then conveyed to the nursery field for further acclimatisation. The designed system consists of three main units: the -conveying unit, the tray-relocating unit and tray-destacking unit. A programmable logic controller with a frequency converter, was used to process the sequential events. The experimental results showed that the system worked at a tray discharge rate of 1,671.8 trays per hour, with a 98.1% success rate for the processes. Farmers appraised the system in terms of functionality and stability. In the future, the system throughput will need to be further increased to allow commercialisation.

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熊本県天草郡天草町下田付近の古第三系からTaxodioxylon matsuiwa WATARIの珪化木に穿孔した管状化石を採集した。化石は保存良好な殻とパレットにより, Bankia属に含まれる新種であることが認められたので, ここに新種Bankia amakusensis, n. sp.として記載した。

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In the near future, many sensors and terminals will be connected to the public network to provide various convenient IoT/M2M services. In order to connect many sensors to the network efficiently, wireless communication systems in the 920MHz band are seen as attractive solutions. We are focusing on the 920MHz band to research and develop high-capacity protocols that can accommodate many terminals, and low power consumption technologies for battery-driven terminals. In this paper, we describe the following three concrete wireless systems that use our proposals. (1) A physical distribution

management system that can handle thousands of -embedded sensors and a wireless module with a battery lifetime of about ten years. (2) Water leakage monitoring system for underground pipes by using sensors and a wireless module in each valve box. (3) A wide-area and high-capacity radio relay system for smart metering services like the reading of gas meters. The radio relay system can accommodate various sensors and terminals and has large potential for providing various IoT/M2M services in conjunction with smart metering services.

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In the study, for the iron sintering process which is strongly time-delayed and confounding, a data-driven modeling method called subspace modeling method is proposed to predict the burn-through point (BTP) in this paper. First, by analyzing the mechanism of the sintering process and processing the industrial data, the relationship between the exhaust gas temperature and bellows is confirmed. Then, based on the position of the BTP, a subspace modeling method is used to establish a temperature identification model. This model outputs, the temperature of the BTP and its inputs include the exhaust gas temperature of the front three bellows and the operating parameters. Finally, we compare the obtained result with those of other algorithms. The simulation experiment shows the effectiveness and veracity of the subspace model for BTP, which will provide a precise model for controller design.

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Objectives: The purpose of this study was to examine the cause of an accidental death from acute poisoning resulting from exposure to a cleaner containing tetramethylammonium hydroxide (TMAH) and to consider measures to prevent future cases. Methods: The authors examined the details and the reason for the accidental death from acute poisoning based on the autopsy report. Results: The victim was a 39-year-old male researcher with 7 years of work experience employed by a surfactant production company. The accident occurred when he was conducting a field test of a newly developed cleaner, containing 8.75% TMAH solution. The researcher spilled the cleaner on his work clothes in the area of both the hands/arms and legs. He was unconscious when discovered. An autopsy found no damage or injury that could have resulted in death other than burns to 12% of his body, and the cause of death was found to be acute poisoning by TMAH. Discussion: TMAH is widely used in the electronics industry as a developer or cleaner. It is a dangerous material, causing neurotoxicity leading to respiratory failure by ganglion block that occurs through skin absorption, and no antidote has been developed yet. For this reason, it is best to completely prevent exposure by wearing proper personal protective equipment. Despite this fatal toxicity of TMAH, it is not classified in Korea as a “chemical requiring legal control”. For this reason, it is urgent to raise awareness of the toxic properties of TMAH to prevent additional cases of TMAH poisoning.(J Occup Health 2013; 55: 120–124)

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As opposed to highly centralized present systems, cellular-type machines were proposed. A cellular-type machine is a mechanical system composed of distributed autonomous intelligent units, called cells, of as few kinds as possible, and with no central control. In our most recent work, we have introduced the concept of movable cells (cells with the introduction of moving function) as a method to improve the robustness against faults and the flexibility of the previously developed system. In the present work we describe the development of a (movable) cellular manufacturing system, which presents characteristics such as real-time scheduling, self-assembly, and enhanced robustness against faults.

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