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Gantry cranes used for container handling at container terminals (hereinafter referred to as cranes) have experienced unexpected runaways caused by wind. In the present paper, a method of dynamic simulation analysis for runaway of cranes caused by wind is described and the dynamic behavior of a standard-size crane while approaching runaway and after runaway as a result of a wind gust was clarified. In the dynamic simulation analysis, the crane was modeled by combining three-dimensional finite elements. The interaction forces generated between the wheels and the rails and the braking force of the rail clamps used to prevent crane runaway as a result of wind were modeled and calculated. The time change of wind velocity of a wind gust was modeled in terms of the increase ratio and the time change rate, and the wind load acting on the crane was calculated. Based on these models, a standard-size crane was analyzed herein. According to the analysis results, when the gust acted in the rail direction under the condition in which the friction coefficients between the pads of the rail clamps and the rails and those between the wheels and the rails decreased, the sea-side clamp pads and driving wheels entered the slip state, after which the land-side clamp pads and driving wheels entered the slip state. Then, the entire crane started to run away. Due to the time lag like this, the crane may run away even though the total wind load is smaller than the total resistance force acting to prevent runaway, which is simply calculated as the sum of the maximum static friction forces generated between the clamp pads and the rails and between the wheels and the rails. Moreover, although the increase ratio of the wind velocity is small, if a wind gust having a large time change rate blows and the fluctuation of the inertial force in the rail direction becomes large as a result of the swinging of the upper part of the crane, the probability of crane runaway increases when the inertial force increases in the runaway direction.

An advantage of Japan is that high-quality safety management and production technologies have been implemented at worksites by workers, managers and production engineers. If European technologies and social systems for safety of machinery are appropriately implemented on the basis of these "onsite capabilities," a new technology and social system framework based on Japan's own onsite capabilities may be created. This study examined the laws, regulations, and social systems that are favorable for safety of machinery in Japan. In maximizing onsite capabilities for safety management, the following four activities were presumed important: (1) the positioning of safety as an investment for new value creation, not a cost; (2) the sharing of a strong sense of ownership and common values for building a safe workplace among involved individuals; (3) the changes in strategies from prevention of recurrence to proactive prevention and from considering the number of accidents to considering the severity of accident; and (4) the consideration of unexpected problems. In addition to the aforementioned activities, the basic principles of machine safety and accident prevention in Europe were considered particularly important for spreading and promotion among corporate executives and machine designers. These principles are the (1) risk reduction strategies provided by the International Organization for Standardization (ISO 12100); (2) conformity assessments that use a modular approach and marking aimed at conveying information about declarations of conformity; (3) validity confirmation when using a machine based on marking information; and (4) feedback regarding disaster information for the design and manufacturing stages of a machine. Language: ja

As material-handling equipment for unloading bulk materials such as iron ore and grain from vessels at harbor piers, continuous unloaders play an important role from the viewpoint of handling performance and environmental protection. Among the various types, belt conveyor-type unloaders are required to provide highly versatile handling performance covering low- to high-fluidity bulk materials. When low-fluidity bulk materials are handled, handling performance decreases and electric energy consumption increases because they do not flow easily into a scraping device. For a scraping device consisting of a horizontal screw and a rotary feeder, this paper proposes a cutting device in which multiple rotatable blades are arranged outside the scraping device. It also describes the basic structure and design guideline of the newly proposed cutting device to improve its low-fluidity bulk handling performance. Furthermore, the driving conditions of the cutting device are optimized, and the improvement of the handling performance is verified by experimental analyses using a model manufactured based on the design guideline. Cement, which is a typical low-fluidity bulk with a large angle of repose, is used for experiments. Low-fluidity bulk materials such as coal, converter slag and soybean meal having some different physical properties from those of cement, such as larger particle size, higher bulk density or higher moisture content, are also examined and discussed as materials for digging. The effect of each physical property on the handling performance, as well as the effect of the proposed device and its effectiveness toward stabilization, are also be clarified, including the basic design and method of optimization.

In recent years, there have been advances in techniques for improving sliding performance by using coated films possessing superior tribological properties to reduce failure of mechanical elements. Those techniques are often used under severe conditions, such as elastohydrodynamic lubrication (EHL). In this paper, to devise the optimum design of a coated film with a gradient layer, the stresses generated in such a coated film are analysed by using a three-dimensional numerical analysis method, and the strength of the film is evaluated numerically. As a result, it is shown that when the ratio of the modulus of elasticity of the coated film, Ec, to that of the substrate, Es, is 0.50, it is preferable to select the gradient layer in which the variation of modulus of elasticity decreases gradually approaching from the substrate to the coated film in the depth direction. Furthermore, it is shown that in the case of Ec/ Es=2.00, it is preferable to select the gradient layer varying linearly the modulus of elasticity into the gradient layer.

Continuous unloaders play an important role in handling bulk materials at ports and so should be fitted with antiseismic devices to protect them in case of emergency by severe earthquakes. Continuous unloaders usually have a hinged-leg type structure and their posture changes over a wide range during operations. For the seismic design of continuous unloaders and to optimize antiseismic devices for them, these features must be taken into consideration and the dynamic behavior of unloaders under representative earthquakes must be clarified. This paper proposes an antiseismic device using linear ball bearing and laminated rubber bearings installed between the traveling gears and the fixed legs on the land side. To clarify the dynamic behavior of a continuous unloader in hinged-leg structure under representative earthquake excitations, experiments using a 1/15-scale model of an actual unloader, modal analysis and time history response analysis using the finite element method were conducted, and the performance of the proposed antiseismic device was investigated. The validity of the finite element analysis was evaluated by experiments using the 1/15-scale model, and the effects of posture on dynamic behavior were also studied in the analysis. The time history of the response acceleration, displacement and the response reaction force at leg points as well as the natural frequencies and modes were calculated and discussed.

In crawler-type construction machines, flexible suspension system like bogie mechanism type suspension is used to reduce and disperse the load acting on the running gear and to absorb the vibration from uneven ground. However, the quantitative effects of the bogie are not so clear. In this paper, by using a modeling and simulation method for crawler-type construction machine with bogie mechanism, which is developed by the authors, in traveling on firm grounds with continuous bumps, representative simulation cases to analyze the dynamic behavior were conducted. Then K-type and X-type bogie as flexible suspension and locked K-type and X-type bogie as rigid suspension were selected. In two bump pitch cases, effects of the bogie mechanism introduction and the bogie type on the dynamic behavior of the machine, such as the lower rollers load and the bouncing and pitching behavior were shown quantitatively and discussed.

Container logistics networks need their expansion and the improvement of their efficiency. For this purpose, the container handling carrying system should be optimized in terminals. Then, it is important to reduce the cycle time for container operation. The operation cycle time is effected by machine performance and the arrangement of containers in stacking yard. In this study, the optimum stacking method in the yard is constructed. As the first step, a stacking method based on fuzzy systems theory has been developed. The judgement of container weight and unloading terminal are treated logically for a container. And the optimum location of a container in stacking yard is decided. The container handling applied this stacking method and conventional ones was simulated. The speed and distance of load hoisting, travelling and traversing are considered in this simulation. As the result, this stacking method is superior to convensional ones in shipping operation time.

In the previous paper, we developed equations of motion for analyzing the dynamic behavior of crawler-type vehicles during straight propelling on soft ground and firm ground. In this study, experiments were carried out in order to verify the validity of the simulation model. The power shovel, a typical example of a crawler-type vehicle, was used in the tests. We measured the dynamic characteristics of the ground to determine the settlement and shear with consideration of hysteresis. The results of experimental tests are in good agreement with the theoretical results. The dynamic behavior of the vehicles, as indicated by parameters such as the dynamic ground pressure, is determined.

Slow vertex response (SVR) to sound stimuli was used as an index to assess whether cortical reactivity in REM sleep with tonic mentalis EMG activity (stage 1-REM) corresponds to that in REM sleep or rather to that in stage 1 of NREM sleep. In 11 young adult subjects 3 night polygraphic records were made after administration of 25 or 50 mg of clomipramine or non-active placebo. Stage 1-REM was observed in the drug night in 8 of the 11 subjects. N 1 -P 2 and P 2 -N 2 amplitudes of SVR were markedly smaller in stage 1-REM than in stage 1, but were virtually of the same height in stage 1-REM and in stage REM. This indicates that cortical reactivity in stage 1-REM closely resembles the counterpart in stage REM. This findings corresponds well with the frequent emergence of vivid dreams in stage 1-REM, indicating that stage 1-REM observed in the present subjects probably represents REM sleep without muscle atonia.