• International Journal of Advanced Culture Technology
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• v.7 no.1
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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.

• Journal of the Korea Furniture Society
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• v.20 no.6
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• pp.566-574
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• 2009

Recent tendency in modern society for urban design and public space forming it recommended diversity of studies and design development, for the interest in urban design is increasing. In particular, street furniture being one of the important components to construct public space has been researched and developed in aspects of formative and emotional style, broken from the old way of the function-oriented purpose. It could be said that this results from the desire of human pursuing a well-off life, the new value standard regarding design and the life styles in mode. The new development of street furniture could be a creating the value-added source potentially being able to raise community, identity of nation and international competitiveness, beyond the primary purpose, namely the improvement of surrounding environment, and therefore the most of countries in the world are concentrating their life and death on development of design in reality. For this investigation the concept of city design, the basic content analysis of the street furniture and also the contents in the related sectors were reported. In order to develop the bench design, one of the representative items of the street furniture furthermore it was proceeded that basic process for the design like data searching for the object place and the existing case studies. On the basis of this the series of the design development processes such as idea sketch, computer rendering and drawing work were described step by step. The aim of this study is therefore to contribute in compiling the development processes of bench design as a new shape into a data and in utilizing it as a design case study and research material in the related sectors.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.267-268
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• 2002

Engine testing of new low-sulfur, low-phosphorus anti wear components is expensive and time consuming so bench testing of potential candidates is highly desirable as a first step evaluation. Electrical contact resistance (ECR) has been shown to be a convenient method to assess antiwear film formation in a ball-on-flat bench wear test. Correlation of the bench test to fired engines was demonstrated for lubricants varying only in the type of detergent. Previous papers have examined film formation by one and two component formulations of zinc dialkyldithiophosphate (ZnDTP) and detergents. In this study, the ECR technique is systematically extended to formulations including ZnDTP, detergent, and dispersant. Both type and level of components are considered and the implications for engine performance are discussed.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.10
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• pp.2667-2677
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• 1995

A new numerical algorithm using equal order linear finite element and fractional step method has been developed which is capable of analyzing unsteady fluid flow and heat transfer problems. Streamline Upwind Petrov-Galerkin (SUPG) method is used for the weighted residual formulation of the Navier-Stokes equations. It is shown that fractional step method, in which pressure term is splitted from the momentum equation, reduces computer memory and computing time. In addition, since pressure equation is derived without any approximation procedure unlike in the previously developed SIMPLE algorithm based FEM codes, the present numerical algorithm gives more accurate results than them. The present algorithm has been applied preferentially to the well known bench mark problems associated with steady flow and heat transfer, and proves to be more efficient and accurate.

• Proceedings of the KSME Conference
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• 2000.04b
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• pp.709-714
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• 2000

A splitting method for the direct numerical simulation of solid-liquid mixtures is presented, where a symmetric pressure equation is newly proposed. Through numerical experiment, it is found that the newly proposed splitting method works well with a matrix-free formulation fer some bench mark problems avoiding an erroneous pressure field which appears when using the conventional pressure equation of a splitting method. When deriving a typical pressure equation of a splitting method, the motion of a solid particle has to be approximated by the 'intermediate velocity' instead of treating it as unknowns since it is necessary as a boundary condition. Therefore, the motion of a solid particle is treated in such an explicit way that a particle moves by the known form drag (pressure drag) that is calculated from the pressure equation in the previous step. From the numerical experiment, it was shown that this method gives an erroneous pressure field even for the very small time step size as a particle velocity increases. In this paper, coupling the unknowns of particle velocities in the pressure equation is proposed, where the resulting matrix is reduced to the symmetric one by applying the projector of the combined formulation. It has been tested over some bench mark problems and gives reasonable pressure fields.

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.5
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• pp.303-305
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• 2003

Scale-up of hirudin production from Saccharomyces cerevisiae from bench-scale to pilot-scale was carried out based on constant volumetric oxygen transfer coefficient (K$\sub$L/a). Fed-batch mode of cultivation using step-wise feeding strategy of galactose was employed for the production of hirudin in a 30-L and a 300-L pilot-scale fermentor. The final hirudin concentrations were achieved 390 mg/L and 286.1 mg/L, and the volumetric productivities were 80.4% and 90.7% with the 30-L and 300-L fermentors, respectively, compared to the productivity of the 5-L bench-scale fermentor.

• Journal of Korean Tunnelling and Underground Space Association
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• v.7 no.4
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• pp.335-341
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• 2005

In construction of a large cross section NATM tunnel, to keep the tunnel face stability by the ground itself bench cut method is commonly used. In order to necessity of partial face excavation method, we have to look for more enhanced method that can maintain better stress intensity. This paper presents a stress distribution of the Center Diaphragm Method from the partial face excavation methods, with the numerical analysis, and induced the optimal face distance, which is minimizing stress concentration and the optimal excavation step. Commerical 3 dimensional continuum analyzing FLAC-3D Ver. 2.1 program is used for the analysis. Analyses were performed to investigate ground behavior for tunnels with variable bench-length varying from 2m to 40m.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.2
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• pp.60-66
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• 2004

Increased energy costs have placed demands for improved combustion efficiency, high equipment availability, low maintenance and safe operation. Simultaneously low NOx modification, installed due to stricter environmental legislations, require very careful combustion management. The flame diagnostics system has been developed specially to meet these requirements. We aimed at gaining the relationship between burner flame image and emissions such as NOx and unburned carbon in furnace by utilizing the image processing method. For the first step of development, its possibility test was undertaken with bench furnace. The test proceeded to the second step with pilot furnace, the system was observed to be effective for evaluating the combustion conditions.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.499-502
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• 2003

Increase energy costs have placed demands for improved combustion efficiency, high equipment availability, low maintenance and safe operation. Simultaneously low NOx modification, installed due to stricter environmental legislation, require very careful combustion management. We aimed at gaining the relationship between burner flame image and emissions such as NOx and unburned carbon in furnace by utilizing the image processing method. For the first step of development, its possibility test was undertaken with bench furnace. The test proceeded to the second step with pilot furnace, the system was observed to be effective for evaluating the combustion conditions. By using this technology, it is possible to perform continuous monitoring of the combustion conditions and instant detection of individual changes for each burner to prevent future loss of ignition.

• Korean Journal of Health Education and Promotion
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• v.24 no.5
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• pp.119-135
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• 2007

Objectives: The efficacy, feasibility, and safety of bench-step aerobics (BSA) program in overweight or obese Korean adult women have been implied. However, there has been almost no evidence for its psychological benefits. As such, the purpose of this study was to investigate the psychological benefits of BSA program in overweight or obese (body mass index ${\geq}\;23\;kg/m^2$) Korean adult women. Method: Anger, exercise self-efficacy, exercise-related affect, and body image of overweight or obese women who participated in a 12-week BSA program (n=15) were compared with those of their counterparts in the control group (n=13). Subjects were selected among public health center visitors and those recruited by putting an advertisement in local newspapers and the public health center homepage. Data from the exercise and control groups were collected before and after the 12-week BSA program (from August to November in 2006) at the public health centers. The exercise program consisted of 45 to 60 min moderate-intensity (40/50 to 50/60% of their hear rate reserve) BSA performed for 3 days a week. Results: After the BSA program, body image of the subjects in the exercise group was significantly improved and there was a significant difference between the exercise and control groups. Anger, exercise self-efficacy, and exercise-related affect were improved after the BSA program but the changes did not reach the level of statistical significance and there were no significant differences between the exercise and control groups. Conclusions: In conclusion, BSA appears to significantly enhance body image in overweight or obese Korean adult women but its effects on anger, exercise self-efficacy, and exercise-related affect do not appear to be statistically significant. Further studies involving different subjects, particularly whose levels of anger are high or whose levels of exercise-related affect are low to exclude the influence of the ceiling or floor effect, are warranted in a randomized controlled design.