• International Journal of Industrial Entomology and Biomaterials
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• 제44권1호
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• pp.12-20
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• 2022

In this research, the silk web was hot-pressed for various times, the effect of press time on the structure and mechanical properties of silk non-woven fabric was also investigated. The yellowing appeared in the silk non-woven fabric and became more apparent as press time was increased. The crystallinity of silk was decreased by the hot press treatment and it did not change significantly with an increase of hot press time. The porosity of silk non-woven fabric was constantly decreased until 120 s and it did not change much after that. The thickness of silk non-woven fabric was significantly decreased by a press time of 10 s and slightly decreased with a further increase of hot press time. The hot press treatment increased the maximum stress and elongation of silk non-woven fabrics. The press time had a significant impact on the mechanical properties of silk non-woven fabric, with 90 s being the optimum condition for the best work of rupture of silk non-woven fabric.

• 한국기계가공학회지
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• 제12권5호
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• pp.86-93
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• 2013

Main function of the Press forming Machine is the forming for plates. The head of the Press forming machine consist of several parts. It was named Press forming-contraction and Press forming_expansion according to formability of plates. Aluminium and Titanum plates are forming by using the Press forming machine. In this study, we analyzed sheet metal forming including plastic deformation and the contact pressure in the bearing. Finite element analysis results of Press forming-contraction and Press forming_expansion show the similar results of the actual specimen plates and the bearing contact pressures show the acceptable level of stress in both aluminum and titanium specimens.

• 한국운동역학회지
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• 제16권4호
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• pp.189-194
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• 2006

The purpose of this study was to identify the relationship of one repetition maximum between flat bench press exercise and incline bench press exercise, and so 40 male students of U-university were sampled purposedly, who were skilled in flat bench press and incline bench press exercises. After measuring lRM of each exercise by free barbell weight, the correlation analysis and the simple regression analysis were examined by using SPSS 120 at a significance level .05. The conclusions were as follows; Firstly, it was identified that 1RM of flat bench press exercise and incline bench press exercise were $89.2{\pm}25.9kg$, $67.1{\pm}22.1kg$ respectively, and the coefficient of correlation between two variables was 0.969, so the relationship was positive correlation. Secondly, it was identified that the regression equation predicted 1RM of incline bench press exercise was significant actually and statistically, so it was expressed that the equation was -6.648 + 0.827 (1RM of flat bench press exercise).

• Asian-Australasian Journal of Animal Sciences
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• 제22권11호
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• pp.1531-1539
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• 2009

This study compared the nutritional value of canola (B. napa) and mustard (B. hirta) press cakes obtained from the biodiesel industry as ingredients for use in diets fed to broiler chickens. A total of 210, one-day old, male broiler chicks were randomly assigned to one of seven dietary treatments. The control diet was based on wheat and soybean meal and contained 15% canola meal. For the experimental diets, 5, 10 or 15% of the canola meal was replaced with an equal amount of either canola or mustard biodiesel press cake. Dry matter and neutral detergent fiber digestibility were significantly higher for birds fed diets containing either canola or mustard biodiesel press cake compared with canola meal. Dry matter and neutral detergent fiber digestibility of the canola biodiesel press cakes was higher than the mustard biodiesel press cakes. Ether extract digestibility and nitrogen retention were significantly higher for birds fed canola biodiesel press cake compared with canola meal and mustard biodiesel press cake. Body weight gain and feed intake did not differ between birds fed canola or mustard biodiesel press cake and canola meal. In addition, there was no significant difference in body weight gain or feed intake between birds fed diets containing canola or mustard biodiesel press cake. Feed conversion was significantly improved for birds fed either canola or mustard biodiesel press cake compared with canola meal. Mortality was unaffected by treatment. Since the performance of broilers fed canola biodiesel press cakes was essentially the same as that of broilers fed canola meal, it is difficult to justify a premium to be paid for canola biodiesel press cake over that paid for canola meal. In addition, there was no difference in the performance of broilers fed biodiesel press cake obtained from canola or mustard seed. As mustard seeds are generally available at a lower price than canola seed, there may be some incentive to use mustard rather than canola seed for producing biodiesel press cake for use in poultry production.

• 열처리공학회지
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• 제21권4호
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• pp.189-198
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• 2008

The production of automotive chassis parts requiring both high hardness and good shape-holdability is better realized by using press quenching technology, comprising the austenitizaton and the subsequent press quenching in a specially designed stamping tool. The effect of press quenching mold shape on the hardness distribution, bending height, and degree of planeness of automotive flexible plate during press quenching and tempering has been investigated. The preferable shape of the projections of punch and die in contact with the flexible plate was close to oval to improve the flow of cooling oil, leading to the higher hardness. The press quenching mold with three separate parts was more effective to control the dimensional change due to thermal deformation during press quenching. Some decrease in the bending height during tempering may be related to some recovery of the residual stress at $400^{\circ}C$.

• Design & Manufacturing
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• 제17권4호
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• pp.14-23
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• 2023

The electric vehicle market is developing rapidly around the world. Also, parts of electric vehicles require precision.In order to produce high-precision motor cores,Press equipment must also have good precision. Drive motor cores are an important technology for electric vehicles. It uses a large high-speed press to mass-produce drive motor cores. Because it's a large high-speed press, there are many reasons why the precision is not good. One of the causes is vibration and noise. Recently, as environmental demands have become stricter, regulations on noise and vibration have been strengthened. It is important for press machines to reduce vibration first for sound insulation and dust proofing. This is because the "breakthrough" phenomenon occurs in the press. Dynamic precision is the precision under the load of the press, Design considering strain and stiffness shall be made. Vibration and noise may occur due to SPM of high-speed press,And vibration and noise can cause structural deformation of the press. Structural deformation of the press can affect the precision of the product.Noise and vibration also cause problems for workers and work environments. Problems with vibration and noise occur during press processing, and vibration and noise lead to damage to the mold or defects in the product. Reliability in high-quality technology must be secured with low noise and low vibration during press processing. Modular shape and deformation energy effects were analyzed through finite element analysis. In this study, a study on vibration and noise countermeasures was conducted through finite element analysis of a large high-speed press.

• The Journal of Korean Physical Therapy
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• 제25권4호
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• pp.180-186
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• 2013

Purpose: This study was to find a correlation between the bilateral reciprocal leg press test and a the balance in chronic stroke patients. Methods: Eighteen patients performed an isokinetic leg press test consisting of a bilateral reciprocal and unilateral mode. Following the isokinetic leg press testing, subjects performed the balance test: Berg Balance Scale (BBS), Timed Up & Go (TUG) test, and stability limit. Pearson product moment correlation coefficients were used to determine the correlation between the mean score of the isokinetic leg press test, balance test in both affected and non-affected side. Results: This study indicated a significant correlation between the bilateral reciprocal leg press test and stability limit. There were significant correlation between non-affected side bilateral leg press(NBL) and BBS (r=0.501), affected side bilateral leg press (ABL) and non-affected side stability limit(NS) (r=0.614), ABL and total stability limit (TS) (r=0.493), NBL and affected side stability limit(AS) (r=0.480), NBL and NS (r=0.560), NBL and TS (r=0.563), among the patients. Conclusion: Measurement of the lower extremity strength using the bilateral reciprocal leg press test can be used as an evaluating tool of the balance test.

• International Journal of Advanced Culture Technology
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• 제7권1호
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• pp.209-215
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• 2019

In order to provide a safe free-weight-training environment to people without workout trainers, we suggest a smart bench press machine with an automatic weight control system sensitive to user tiredness. Physical weight plates on the machine are replaced with a hydraulic cylinder as a press load and the cylinder knob is coupled with a step motor to change its tensile force automatically in-between lifting exercises. Three subjects participated to verify the usability of the smart bench press machine. They were asked to lift a 6-RM press load 10 times with 3 different lifting conditions: 1) no assistance, 2) a human assistance, and 3) the automatic weight control. All subjects were not able to complete the 10 sets without assistance due to tiredness, but they finished the full sets under the two assistive conditions. Average lifting speeds under the automatic weight control condition showed the most consistent level. Normalized quasi-tension data based on surface electromyogram signals of both Pectoralis Majors revealed that the subjects maintained the target muscle activation level above 50% but not more than 80% throughout the 10 sets. Therefore, the smart bench press machine is expected to both keep pace with the lifting exercise and reduce risk of injuries due to excessive muscle tensions.

• Tribology and Lubricants
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• 제21권4호
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• pp.185-192
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• 2005

The press cutter is productive equipment that practically manufactures mechanical components and polymer-based materials such as fabrics, papers, films, leathers, and rubbers into the desired shapes using a press cutting tool. The plate cutting process is one of the primary energy absorbing mechanisms in a grounding or collision event between a press cutter and a material on a die. The cutting mechanism is complicated and involves plastic flows of a plate in the vicinity of the tip, friction between the wedge and the plate, deformation of the plate. In this paper, we studied the effect of friction between cutter and plastic sheet far producing precise and superior products. In this paper, the press cutter is analyzed numerically using MARC finite element program for a optimization design of a press cutter. The FEM computed results show that the maximum von Mises stress is concentrated on the tip of a press cutter, which may lead to the edge wear or impact wear of the sharp cutter. Based on the FEM result and Taguchi's experimental design method, the optimized design model 9 for a press cutter is recommended as a best one.

• Design & Manufacturing
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• 제16권4호
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• pp.40-45
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• 2022

The EV electric vehicle market is growing rapidly worldwide. An electric vehicle means a vehicle that uses energy charged through an electricity source as power. The precision of the press is important to mass-produce the drive motor, which is a key component of the electric vehicle. The size of the driving motor is increasing, and The size of the mold is also growing. In this study, the precision of large high-speed presses for mass production of driving motors was measured. A study was conducted on the measurement method of press and the analysis of measurement data. A drive motor is a component that transmits power by converting electrical energy into kinetic energy. EV driven motors have key material properties to improve efficiency. The material properties are the thickness of the material. As a method for improving performance, use a 0.2mm thin steel sheet. Mold is also becoming larger. As the mold grows, the size of the high-speed press for mass production of the driving motor is also increasing. Also, the precision of the press is the most important because it uses a thin iron plate material. So the importance of large press precision is being emphasized. In this study, the effect of large high-speed press structure on precision was verified