• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.6
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• pp.197-204
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• 2003

This paper develops a computer model for estimating the handling of a cabover type large-sized truck. The truck is composed of front and rear suspension systems, a frame, a cab, and ten tires. The computer model is developed using ADAMS. A shock absorber, a rubber bush, and a leaf spring aunt a lot on the dynamic characteristic of the vehicle. Their stiffness and damping coefficient are measured and used as input data of the computer model. Leaf springs in the front and rear suspension systems are modeled by dividing them three links and joining them with joints. To improve the reliability of the developed computer model, the frame is considered as a flexible body. Thus, the frame is modeled by finite elements using MSC/PATRAN. A mode analysis is performed with the frame model using MSC/NASTRAN in order to link the frame model to the computer model. To verify the reliability of the developed computer model, a double lane change test is performed with an actual vehicle. In the double lane change, lateral acceleration, yaw rate, and roll angle are measured. Those test results are compared with the simulation results.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.409-414
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• 2007

Nowadays, with the advancement of computational mechanics, and vehicle dynamics simulation linked up with virtual testing laboratory(VTL) and virtual proving ground(VPG) technologies has become a useful method for analyzing numerous driving performances and diverse noise/vibration characteristics. In this paper, the analytical vehicle model based on multi-body dynamics theory was developed to investigate the vibration characteristics according to various road conditions. For the purpose, the whole vehicle parameters, each vehicle's part parameter, and part connecting elements such as spring, damper, and bush were measured by an experiment. Also, the vehicle dynamics model, which includes the front suspension, rear suspension, steering, front wheel, rear wheel, and body subsystems has been constructed for computer simulation. With the developed vehicle dynamics model, three forces and three moments measured at each wheel center were applied to evaluate and analyze dynamics and vibration characteristics for miscellaneous road conditions.

• Journal of the Korean Institute of Landscape Architecture
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• v.28 no.6
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• pp.106-113
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• 2001

The purpose of this study is to find out the effect of recovery from psychological stress when watching plants indoors. As an instrument of measurement of psychological stress, Galvanic Skin Resistance(GSR) has been used because it has been convenient to read a psychological sign without a medical sense and an instrument. In order to make the conditions of stress and recovery, video programs have been made, and especially, the video program of recovery has consisted of three types-- types 1 of watching plants in a botanical garden, type 2 of watching very bush street, and type 3 of closing eyes naturally. The two groups of normal and the mentally handicapped persons have been participated in this experiment to compare the effect of recovery. As the result of this test, the rate of stress relief has been maximumly effected by watching the video program of plants. Between the two groups the recovery of stress has had better effects on the mentally handicapped than the normal one. And also it shows that the circumstances of emotional refinement is led by having plants in indoor. The result of this test has been turned out to be highly useful. It is desirable that a indoor worker, staying for a long time, contact with plants visually to keep healthy mental conditions. This study suggests that the surrounding conditions or the settings of circumstances play an important role for the emotional refinement of the groups of mentally han야capped persons as well as the normal person.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.1
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• pp.163-181
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• 1998

In this study, the objective is determine the optimal design variable of engine mount system using the rubber mount of bush-type which is usually utilized in passive control to minimize vibrations of vehicle body or transmission from engine into body. The engine model adopted in this study is 4-cylinder, 4-stroke gasoline engine support- ed by 4-points. The system is modelled in 10 d.o.f.-rigid body motion of the engine & transmission in 6 d.o.f., elastic motion of vehicle body in 4 d.o.f.(1st torsional, 1st vertical and 1st & 2nd lateral bending vibration mode). To consider the elastic motion of vehicle body, find the eigenvalues and mode shapes of vehicle body by nodal testing and then determine the modal masses and stiffnesses of the body. The design variables of the engine mount system are locations, stiffness and damping coefficients of the rubber mounts(28 design variables). In case of considering the torque-roll axis for the engine, the design variables of the mount system are reduced to 22 design variables. The objective functions in optimal design process are considered by three cases, that is, 1) transmitted forces through engine mounts, 2) acceleration components of generalized coordinates for the vibration of vehicle body, 3) acceleration of specified location(where gear box) of body. three case are analyzed and compared with each other.

• Journal of the Korea Furniture Society
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• v.18 no.1
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• pp.70-83
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• 2007

Rattan furniture is strips of cane around the frame that consists of wisteria, bamboo and wood. The materials are originally from Southeast Asia, and the material of domestic Rattan goods is Korean wisteria. Rattan, which is strong and elastic, is often used for craft materials, and it also retains the original feel of the material with great touch. It is beautiful and suitable for expressing curves. It is shiny, light in weight, easy for cleaning and ventilation. Rattan furniture is unique product made by human hands and nature and is an environment friendly well-being furniture. The use examples of these domestic rattan furnitures is condensed as below. First, the materials of rattan product is wisteria, rice straw, bush clover wood, reed and bamboo. Second, the use of rattan product which is made of domestic wisteria is limited to farming equipments and living wares. Third, the materials of rattan furniture differs in domestic made and foreign made product. As is the characteristics of timbers growing in warmer climates of Korea, it has many twist and strong and it is not straight in length so it is hard to manufacture into and use as furniture also it is hard to acquire right size for the material.

• Korean Journal of Food Science and Technology
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• v.20 no.5
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• pp.631-636
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• 1988

Quality of five kinds of honey, from acacia, bush clover, chestnut, rape and polyflower sources, were evaluated by physicochemical methods in respect to some chemical constituents. The average values for the tested honeys were: moisture, 19.5%; fructose, 33.74% , glucose. 35.03%; sucrose, 4.67%; hydroxymethylfurfural, 6.17mg,/kg; total nitrogen, 0.027%, proline, 23.67mg%; lactone, 4.09meq/kg; free acidity, 11.37meq /kg; and total acidity, 15.46meq/kg.

• Korean Journal of Materials Research
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• v.9 no.4
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• pp.398-403
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• 1999

Studies on the electrical treeing deterioration and dielectric breakdown phenomena in the polymeric insulator of polyethylene and epoxy resin were carried out. Block type samples with needle-plane electrode geometry were electrically stressed and the tree pattern from the needle tip was observed. In LDPE the density of electrical tree was very high and its pattern was bush type. For the case of XLPE, branched tree was observed. As temperature and SN content increased, the dielectric breakdown voltage decreased and the treeing phenomena became more complicated. Fan type cracks were observed around the conducting tree path in the brittle DGEBA/MDA system.

• Child Studies in Asia-Pacific Contexts
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• v.4 no.2
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• pp.95-108
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• 2014

The purpose of this study was to examine group differences in paternal behaviors (i.e., paternal connection, paternal punitiveness, and paternal knowledge) within and across three academic achievement levels-low, moderate, and high, and to explore the effects of paternal behaviors on the academic motivation of Chinese adolescents within these three achievement groups. Analyses of variance (ANOVAs) indicated that adolescents with low achievement perceived their fathers as more punitive than teens with moderate and high academic achievement. Regression analyses also revealed that paternal punitiveness (negative) and paternal knowledge (positive) were significant predictors of academic motivation for teens with low levels of academic achievement; while paternal punitiveness was a significant negative predictor of academic motivation among adolescents with moderate achievement. In contrast, for adolescents with high achievement, paternal connection was a positive significant predictor of academic motivation. The present findings provide some evidence that the impact of parental behaviors on teen's motivation varies across adolescent academic achievement levels, which may prove useful for professionals working with fathers to help target the most effective parenting behaviors to foster academic motivation.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.5
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• pp.111-117
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• 2020

Centrifugal casting is suitable for producing hollow-products using centrifugal force. Bush type metal bearings are the key parts that facilitate the rotational movement of various machinery. Metal bearings produced by conventional centrifugal casting machines show rotational imbalance. Therefore, after injecting a large amount of material, the product's precision is secured in the secondary processing. Rotational imbalance is caused by the force acting on the rotary disc plate. In order to minimize rotational imbalance, NASTRAN was used for the optimal design and structural analysis. It was concluded that the rotating plate of the conventional centrifugal casting machine should be prevented from tilting. For this purpose, the location & thickness of the stiffeners were obtained through the optimum design. In the conventional centrifugal casting machine, both ends of the product are lower in temperature than the center part, so internal stress occurs. This solves this problem by inserting a heating coil into the rotating plate.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.15 no.10 s.103
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• pp.1202-1210
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• 2005

This paper develops a computer model for estimating the bump characterisitcs of a cat)over type large-sized truck. The truck is composed of front and rear suspension systems, a frame, a cab, and ten tires. The computer model is developed using MSC.ADAMS. A shock absorber, a rubber bush, and a leaf spring affect a lot on the dynamic characteristic of the vehicle. Their stiffness and damping coefficient are measured and used as input data of the computer model. Leaf springs in the front and rear suspension systems are modeled by dividing them three links and joining them with joints. To improve the reliability of the developed computer model, the frame is considered as a flexible body. Thus, the frame is modeled by finite elements using MSC.PATRAN. A mode analysis is performed with the frame model using MSC.NASTRAN in order to link the frame model to the computer model. To verify the reliability of the developed computer model, a double wheel bump test is performed with an actual vehicle. In the double wheel bump, vortical displacement, velocity, acceleration are measured. Those test results are compared with the simulation results.