• Composites Research
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• v.33 no.6
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• pp.360-364
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• 2020

Although research and development of existing steel-made Cowl Cross Member(CCM) was carried out with magnesium and plastic to make vehicles lighter, it is difficult to apply them to performance problems in the vehicle's mounting condition. Recently, the company is conducting research on the injection CCM of the composite insert as a lightweight component that is most suitable for mass-production of automotive parts. This is a manufacturing process that inserts composite injection bracket parts into aluminum bar, and the adhesion of the two parts is one of the important factors considering the vehicle's mounting conditions. In this study, the joint strength of Aluminum bar is one of the important factors as a study for the injection of aluminum bar into PA6-GF60 composite material. For the analysis of these research, the method of spraying adhesive to the aluminum bar and the case of knurling treatment have been analyzed and the bonding strength of the direction of rotation and lateral direction has been analyzed for each part between the aluminum bar of the cowl cross member and the shape of the injection component of composite materials.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.3
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• pp.115-121
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• 2021

Human's landing strategies have been explained through lower extremity kinetics in various conditions. However, how lower extremity kinetics respond when the two conditions between a load and landing height are combined is not yet understood. To achieve the purpose of this study, a total of 20 men and women were subjected to drop landing according to a load(No load, 10%, 20%, 30% of the body weight) at various landing heights(0.3 m, 0.4 m, 0.5 m). As a result of the study, the main effect of a load was not statistically significant in all variables. But increasing of the landing heights showed more flexion angle which was statistically significant in knee joint. In addition, as the landing height increased, the medial-lateral, anterior-posterior, vertical force, and loading rate increased, while time to peak vertical force decreased which was statistically significant. Thus, humans can successfully perform the landing motion even if the load is changed at various heights. However, it reacted more sensitively to the change in landing height than that load condition. The landing height can be prepared for recognition and shock absorption through visual information, but the weight level is difficult for the body to perceive and explains why it is more difficult to apply it to the landing strategy mechanism for shock absorption.

• Journal of agriculture & life science
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• v.53 no.4
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• pp.113-124
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• 2019

In this study, the operational characteristics of a cam-type vegetable transplanter which usually used in domestic was analyzed and operating mechanism of a transplanting device was analyzed. The main components and power path of the transplanter were analyzed. The maximum and minimum control cycles according to the moving speed and the plant spacing were analyzed. 3D modeling and simulation were performed to derive the trajectory of the bottom end of the transplanting hopper and the plant spacing at the each operating condition. The simulation results were verified by the field tests. As main findings of this study, the transplanting device has one degree of freedom (DOF) which consist of 13 links, 17 rotating joints and 1 half joint, and each part has composite structure with cam and links. By continuous and repetitive motion of the structures of transplanting device, the transplanting hopper plants the seedling in the ground with a vertical direction, and the seedling was planted stably. The power is transmitted to the driving part and transplanting device from the engine, and the maximum and minimum plant spacing of the transplanting device were about 900 mm and 350 mm, respectively.

• Conservation Science in Museum
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• v.26
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• pp.67-82
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• 2021

Two golden beads (Buyeo 5336) housed at the Buyeo National Museum were discovered in 1993 near the site of an ancient workshop in Neungsan-ri in Buyeo-gun, Chungcheongnam-do Province. These rare examples from the Baekje Kingdom of an application of granulation have maintained their original form intact, and thus serve as important materials for the investigation of production techniques applied. This study analyzed the composition of the golden beads using a portable X-ray fluorescence analyzer, a stereo microscope, and a scanning electron microscope with an energy dispersive X-ray spectrometer. The manufacturing technique was examined through the observation of the micro-shape and the surface condition and by a composition analysis of the joint part. In both beads, a hole was pierced in a hollow body and the bead was decorated with golden wires around the hole and gold granules in other parts. In some areas, golden granules had been attached to the gold plate and golden wires were then placed over the granules. The purity of both the wires and the granules was analyzed as 23.6 - 23.7K. A high copper content was detected in some of the parts where the granules were attached. The findings of a previous reproduction experiment and study of production methods suggest that the beads were made using the copper diffusion technique.

• Journal of the Korean Orthopaedic Association
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• v.55 no.2
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• pp.117-126
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• 2020

Total knee arthroplasty is performed widely in degenerative arthritis of the knee joint, and the frequency of use is increasing. Efforts should be made to achieve functional recovery, such as returning to daily life, and the recovery of strength and range of motion after surgery. The procedure should be approached from a range of perspectives, such as patient factors, surgical technique and rehabilitation. The patient's age, degree of obesity, sex, and strength of the quadriceps muscle can affect the functional recovery after surgery. In addition, the patient's mental state, such as expectation value and satisfaction, can also have an effect. For functional recovery, patient education, pain control, and strengthening of the quadriceps muscle can be performed prior to surgery. Postoperative physiotherapy, such as icing and compression, transcutaneous electrical nerve stimulation therapy, neuromuscular electrical stimulation therapy, low frequency low intensity magnetic field therapy, strengthening of quadriceps muscle, and range of motion exercise can also be applied. In recent years, hydrotherapy, which restores the strength and balance of the leg, is being performed increasingly. These treatments are not only performed shortly after surgery, but are also performed continuously. In addition, the surgeon should apply it appropriately considering the patient's condition, compliance, and social and psychological conditions.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.4A
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• pp.361-373
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• 2010

Bridges constructed without any expansion joint or bridge bearing are called integral abutment bridges. They integrate the substructure and the superstructure. Possible deformation of the superstructure, due to changes in temperature for example, is prevented by the bending of the piles placed at the lower part of the abutment. This study examines the behavior of integral abutment bridges through soil-pile interaction modeling method and proposes an appropriate modeling method. Also, it assesses the behavior characteristics of the superstructure and piles of integral abutment bridges through parametric study. Soil condition around the pile, abutment height, and pile length were selected as parameters to be analyzed. Structural analysis was conducted while considering the interactions of soil-pile and temperature change-earth pressure on the abutment. Comparative behavior analysis through soil-pile interaction modeling showed that elastic soil spring method is more appropriate in evaluating the behavior of integral abutment bridges. The parametric study showed the tendency that as the soil stiffness around the pile increases, the moment imposed on the superstructure increases, and the displacement of the piles decreases. In addition, it was observed that as the bridge height increases, the earth pressure on the abutment increases and that in turn affects the behavior of the superstructure and piles. Also, as the length of the pile increased, the integral bridge showed more flexible behavior.

• Korean Journal of Remote Sensing
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• v.39 no.6_1
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• pp.1483-1490
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• 2023

We analyzed the potential for joint utilization of Visible Infrared Imaging Radiometer Suite (VIIRS) satellite imagery Normalized Difference Vegetation Index (NDVI) in crop assessment, considering the aging of MODerate resolution Imaging Spectroradiometer (MODIS) satellites. Over 11 years from 2012 to 2022, we examined the characteristics of NDVI changes in corn and soybean cultivation areas in Illinois, USA. VIIRS and MODIS satellite imagery NDVI exhibited a high correlation coefficient of over 0.98. However, during periods of rapid crop growth or decline, VIIRS NDVI showed values approximately 0.12 to 0.14 higher than MODIS. Estimating crop anomaly classes based on NDVI, we observed similar trends in corn and soybean crop anomaly classes in 2018 and 2019. However, in 2022, there appeared to be a significant divergence in crop anomaly classes, suggesting the need for further investigation. The correlation coefficients between MODIS and VIIRS satellite imagery NDVI and corn and soybean yields were consistently high, exceeding 0.8, indicating the potential for quantity estimation using both MODIS and VIIRS satellite imagery. Specifically, for VIIRS NDVI, excluding the increasing trend in crop quantity estimation for soybeans enhanced the correlation, and compared to MODIS, it showed a consistently high correlation with quantity from approximately 16 days earlier, indicating the potential for early estimation.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.3 no.4
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• pp.1-41
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• 2008

The Korean semiconductor industry has made a great contribution to growth of Korean economy for the last decades by maintaining a top position in terms of Korean total annual export volume. However, the advanced semiconductor equipment and materials that are used for the production of semiconductor devices still depend on the suppliers from Europe, Japan, and America who have an influential position in the Korean semiconductor industry. The objective of this study is to empirically investigate the attributes determining the extent of autonomy in decision making for the Korean subsidiaries of multinational corporations in the semiconductor industry. This study found there were differences in the extent of autonomy in decision making in terms of the global strategies the multinational corporations pursue. This study surveyed employees at the Korean subsidiaries and joint venture companies of semiconductor multinational corporations and collected 726 survey questionnaires. Several statistical analyses including frequency analysis, reliability analysis, factor analysis, multiple regression analysis and ANOVA were performed using the collected sample data. Based on the analyses, this study found as follows: Firstly, from the factor analysis, this study found Korean subsidiaries faced three sources of uncertainties stemmed from political conditions, competent conditions, demand and supply conditions. The internal resources were characterized by the independencies of production capability, financial capability, marketing capability and human resource management capability. The operational performance was determined by total revenue, net profit and market share growth. Secondly, it was found the uncertainties from political condition and competent condition and the independencies of financial capability and marketing capability partially influenced the extent of autonomy in decision making. The independencies of production capability and human resource management capability significantly influenced the autonomy of decision making in the most areas. It was also found an increase of total revenue, net profit and market share growth partially affected the extent of autonomy in decision making of the Korean subsidiaries. Finally, it was found that the polycentrism of global management by multinational corporations seemed to bring a higher extent of autonomy in decision making than ethnocentrism or geocentrism of global management. Based on the results, this study provided managerial implications regarding the extent of autonomy in decision making for Korean subsidiaries of multinational corporations in order to help management to enhance their business capabilities.

• 한국벤처창업학회:학술대회논문집
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• 2008.11a
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• pp.135-168
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• 2008

The Korean semiconductor industry has made a great contribution to growth of Korean economy for the last decades by maintaining a top position in terms of Korean total annual export volume. However, the advanced semiconductor equipment and materials that are used for the production of semiconductor devices still depend on the suppliers from Europe, Japan, and America who have an influential position in the Korean semiconductor industry. The objective of this study is to empirically investigate the attributes determining the extent of autonomy in decision making for the Korean subsidiaries of multinational corporations in the semiconductor industry. This study found there were differences in the extent of autonomy in decision making in terms of the global strategies the multinational corporations pursue. This study surveyed employees at the Korean subsidiaries and joint venture companies of semiconductor multinational corporations and collected 726 survey questionnaires. Several statistical analyses including frequency analysis, reliability analysis, factor analysis, multiple regression analysis and ANOVA were performed using the collected sample data. Based on the analyses, this study found as follow: Firstly, from the factor analysis, this study found Korean subsidiaries faced three sources of uncertainties stemmed from political conditions, competent conditions, demand and supply conditions. The internal resources were characterized by the independencies of production capability, financial capability, marketing capability and human resource management capability. The operational performance was determined by total revenue, net profit and market share growth. Secondly, it was found the uncertainties from political condition and competent condition and the independencies of financial capability and marketing capability partially influenced the extent of autonomy in decision making. The independencies of production capability and human resource management capability significantly influenced the autonomy of decision making in the most areas. It was also found an increase of total revenue, net profit and market share growth partially affected the extent of autonomy in decision making of the Korean subsidiaries. Finally, it was found that the polycentrism of global management by multinational corporations seemed to bring a higher extent of autonomy in decision making than ethnocentrism or geocentrism of global management. Based on the results, this study provided managerial implications regarding the extent of autonomy in decision making for Korean subsidiaries of multinational corporations in order to help management to enhance their business capabilities.

• Journal of Biomedical Engineering Research
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• v.25 no.2
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• pp.157-163
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• 2004

Nitrogen ion implantation and ion plating techniques were applied for improvement of the wear resistance of metallic implant materials. In this work, the wear dissolution behaviour of a nitrogen ion implanted super stainless steel (S.S.S, 22Cr-20Ni-6Mo-0.25N) was compared with those of S.S.S, 316L SS and TiN coated 316L SS. The amounts of Cr and Ni ions worn-out from the specimens were Investigated using an electrothermal atomic absorption spectrometry. Furthermore, the Ti(Grade 2) disks were coated with TiN, ZrN and TiCN by use of low temperature arc vapor deposition and the wear resistance of the coating layers was compared with that of titanium. The chemical compositions of the nitrogen ion implanted and nitride coated layers were examined with a scanting auger electron spectroscopy. It wat observed that the metal ions released from the nitrogen ion implanted S.S.S surface were significantly reduced. From the results obtained, it was shown that the nitrogen ion implanted zone obtained with 100 KeV ion energy was easily removed within 200,000 revolutions from a wear dissolution testing under a similar load condition when applied to artificial hip joint. The remarkable improvement in wear resistance weir confirmed by the nitrides coated Ti materials and the wear properties differ greatly according to the chemical composition of the coating layers. for specimens with the same coating thickness of about 3$\mu\textrm{m}$, TiCN coated Ti showed the highest wear resistance. However, after removing the coating layers, the wear rates of all nitrides coated Ti reverted to their normal rates of below 10,000 revolutions from Ti-disk-on-disk wear testing under the same load condition. From the results obtained, it is suggested that the insufficient depth of the 100 Kel N$\^$＋/ ion implanted zone and of the nitrides coated layers of 3$\mu\textrm{m}$ are subject to restriction when used as frictional parts of load bearing implants.