352 research outputs found

    Winch Harvesting on Flat and Steep Terrain Areas and Improvement of its Methodology

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    With the increase of importance of bioenergy, the whole tree harvesting system was reconsidered. As a simple way of a whole tree harvesting system, this study analyzed two winching procedures in terms of productivity and influence from terrain conditions. One of the winching procedures was observed on flat terrain, where the felled trees were scattered and then, one-by-one, attached to the winch rope. The other was observed on a steep terrain, where the felled trees were concentrated in a line and then attached, at one time, to the winch rope. A significant difference caused by slope conditions appeared only in the reeling velocity. When increasing the harvested volume in a cycle, the productivity increased. The difference in productivity between two sites was slight with the same harvested volume. By the one-by-one procedure, the full volume harvested in a cycle was only skidded from the nearest felling points, while the bundled procedure skidded the full volume from various points including the farthest point. The one-by-one procedure will save the winch rope tension and reduce engine acceleration. Fuel consumption, therefore, will be decreased by applying the one-by-one procedure instead of the bundled procedure. Additionally, reducing the weight of felled trees by natural drying in a forest is effective for reducing fuel consumption not only in transportation but also in winching operation, and for enhancing the calorific value of bioenergy

    Fuel Chip Supply System with Low Price Mobile Chippers

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    High price of chippers and small scale of forestry management area seemed to create a standstill situation of chip utilization system in Japan. By combining the benefits of small scale forestry and low price chippers, a simple and low-cost chip supply model could be established, creating new employments opportunities. The object of this study is to propose the benefits of a chip supply system in small scale forestry using multiple low price chippers at forest landings. The volume of chip material was ranged up to 56 000 m3 in a model area. The results showed that the annual labor cost of the proposed system was higher than that of the conventional system because the utilization ratio of chipper of the proposed system was also higher. The chip supply cost of the proposed system became lower than that of the conventional system because of its proper productivity and machine price. The utilization ratio of machine used in this study will be an important indice for creating employments when establishing chip supply chain. The benefits of the proposed system using multiple chippers are not only creating employments in local community but also bringing flexibility to a stable chip supply system and avoiding the risk of machine workouts and troubles. Therefore, the proposed system that introduces multiple lines using low price chippers will be useful for cost efficient management of small scale forestry and for providing sustainable bioenergy business

    Differences in Mid-Career Childcare Workers’ Views on Their Jobs According to Their Identity Status.

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     This study aims to clarify the differences in mid-career childcare workers’ views on their jobs according to their identity status. The Identity Status Scale (Kato, 1983) was used to assess 269 mid-career childcare workers, and a text mining analysis showed that their identity status reflected the differences in their perceptions of their jobs. For example, for the achievement, positive words such as “doing one’s best” and “efforts” were mentioned. On the other hand, for the diffusion, words regarding aptitude were mentioned, such as “it is suitable.” The differences in mid-career childcare workers’ perspectives on their jobs are also thought to influence them in the second half of their adulthood

    Evaluation of Chipping Productivity with Five Different Mobile Chippers at Different Forest Sites by a Stochastic Model

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    It is important to evaluate chipping productivity that often differed according to the timing of observations and varied unexpectedly. A variation in production was the major concern of stakeholders for sustainable forest operation to establish regularly attainable production schedules on many operational levels. The aim of this study was to estimate the variance of chipping productivity by using a stochastic simulation model to achieve the objective evaluation of chipper performances. Chipping operations of five different kinds of mobile chippers, i.e. three smaller and two middle and larger ones in horse powers, were investigated. Probability distributions of material size and feeding time for chipping in a log-normal distribution were estimated. The estimates were made based on chipping operations performed 2000 or 4000 times by mechanical repetitions. Except for the largest chipper, whose observed productivity was 338 loose m3/hr, all of the observed productivities, varying from 18 to 68 loose m3/hr, were located within a two-sided confidential interval whose difference between both ends was 4 to 10 loose m3/hr. The estimates were, generally, reliable with small variances around the median productivity values in the model. By this stochastic model, chipper productivity could be shown objectively, while the accuracy would be improved more by increasing sample size and accurate material size measurement. It was elucidated that the operations followed by chipping should encompass enough volume capacity to provide stable chipping productivity

    Acute arterial occlusion due to left ventricular thrombus of Takotsubo cardiomyopathy in a young adult: a case report

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    BackgroundThromboembolism is a rare complication of Takotsubo cardiomyopathy. Importantly, an acute arterial occlusion needs rapid diagnosis and urgent treatment to help save the patient’s life. Here, we report a case of arterial occlusion due to ventricular thrombus of Takotsubo cardiomyopathy.Case presentationA woman in her 30s, without previous medical history, felt sudden strong pain on her right leg and was diagnosed with right femoral arterial occlusion. An emergency operation was subsequently performed to take out thrombus. The patient’s oxygenation deteriorated to 93% of hemoglobin saturation just after extubation and exacerbated in the intensive care unit. Transthoracic echocardiography revealed Takotsubo cardiomyopathy-like left ventricular wall motion abnormalities and left ventricular thrombus. Heparin treatment was immediately started. After 10 days, the thrombus disappeared and the left ventricular wall motion improved and she was discharged from the hospital.ConclusionsThe patient’s acute arterial occlusion in this case report was mainly caused by thrombus of cardiac origin. We suggest to routinely check echocardiography reports before surgery and perform anesthetic management carefully to better control the patient’s blood pressure and heart rhythm

    Large-scale stem cell production system by newly designed bioreactor

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    Large scale cell production system is required in drug discovery and cell based therapy. However there are technically challenges in maintaining high quality and low cost for practical biomanufacturing industry. 3D suspension culture is one of attractive process, especially static culture is ultimate free from shear force. Utilizing static 3D suspension culture, automated closed system is newly designed and demonstrated expansion culture over several subcultures. Cell growth curves of this system and conventional manual method have good accordance. The system is also compatible with good scalability for scale up and scale out use. Please click Additional Files below to see the full abstract

    A Source Code Generation Support System Using Design Pattern Documents Based on SGML

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    Applying design patterns to the design of an application makes it robust against issues related to extensibility and maintainability. However, currently, a designer must apply structures and constraints of design patterns to an application by hand, therefore mistakes often occur. We have proposed a notation using SGML for describing design patterns and a support system for design patterns. We aim at providing a source code generation support system based on the notation and system. There has been much research into semi-automatic application generators using existing knowledge such as libraries based on algorithms and data structure, and classes packaged based on the object-oriented technology. When using design patterns for source code generation support, the same requirements for such semi-automatic application generators must be considered. The requirements are lessening codes to be written by users, and satisfying constraints without directing users\u27 attention to them. In this paper we consider the requirements and describe a design and implementation of the source code generation support system and resultsDecember 7-10, 1999, Takamatsu, Japa
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