• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.5
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• pp.26-30
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• 2011

Currently, many researches are carried out about tilting index table, which is one of the main component of 5-axis machine tool. The performance of the tilting index table is associated the rotational accuracy which is very important factor for high precision machining because it have an effect on machining error. In this paper, a tilting index table is developed, and the rotational accuracy of the tilting index table using a laser measurement equipment is measured. In addition, a correction value is obtained from the measured value through compensation, and the correction value is used to improve the accuracy of the table. Comparative analysis is carried out for the accuracy of the table before and after compensation. This paper can be used by a reference for performance and reliability advancement of tilting index table.

• The Journal of Korean Physical Therapy
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• v.19 no.3
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• pp.11-17
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• 2007

Purpose: The purpose of this study were to analyze fatigue patterns of the rectus femoris muscle by isometric contraction. Methods: Twenty healthy subjects(10 male, 10 female) participated in this study. Maximal voluntary isometric contraction(MVIC) was measured by the dynamometer. Muscle activity was recorded from the rectus femoris muscle. During the experiment, the subject was seated in the chair. The measured items, median frequency(MDF) and root mean square (RMS), were collected from the surface EMG. All data were analyzed using repeated measures ANOVA. Results: There was significant difference of MVIC between male and female. Endurance time was significant difference by the level of MVIC but no significant in the main effect(sex) and interaction effect. The MDF and fatigue index were significant differences in the interaction effect. The RMS was not significant difference in both of main and interaction effect. The muscle fatigue patterns of female was greater than male after 60% MVIC. Conclusion: This study showed that sex differences of muscle fatigue were started from 60% MVIC.

• Journal of Korea Trade
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• v.25 no.5
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• pp.93-109
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• 2021

Purpose - The logistics industry is often featured by its location relevance and industrial concentration. Industrial concentration is conducive to the effective transmission of information by reducing transaction costs and improving transaction efficiency, thus promoting the development of trade. The main purpose of this paper is to measure the spatial total factor productivity and location quotient of the logistics industry in Korea, and to study the impact of the logistics industry efficiency and agglomeration effect on import and export trade in Korea. Design/methodology - First, used the spatial stochastic frontier method to measure the spatial total factor productivity of the logistics industry in Korea, this serves as the efficiency index of the logistics industry in various regions of Korea. Second, calculated the location quotient (LQ) of the logistics industry to measure the industry's concentration degree. Third, employed a spatial econometric model to analyze the impacts of factors such as the efficiency and concentration levels of the logistics industry on import and export trade in Korea. Findings - This study's main findings can be summarized as follows: this study found that the overall efficiency of the logistics industry in Korea needs to be improved, even though it showed an upward trend in all regions of the country; Moreover, the agglomeration level of Korea's logistics industry needs to be improved; Finally, the positive spatial correlation and industrial agglomeration effect of Korea's logistics industry had a positive impact on the country's import and export trade. Originality/value - This study is innovative in terms of research perspective and methods. Most of the previous studies have measured the development level of the logistics industry using the logistics performance index (LPI), Fewer studies have assessed through the spatial total factor productivity and location quotient of the logistics industry in Korea to measure the efficiency index of the logistics industry in various regions of Korea and concentration degree, as well as there was almost no study on the impact of logistics industry efficiency and agglomeration effect on import and export trade in Korea. This study addresses this limitation by analyzing the impacts of the efficiency and agglomeration effect of the logistics industry on import and export trade in Korea.

• Computers and Concrete
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• v.21 no.1
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• pp.55-66
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• 2018

A large main shock may consist of numerous aftershocks with a short period. The aftershocks induced by a large main shock can cause the collapse of a structure that has been already damaged by the preceding main shock. These aftershocks are important factors in structural damages. Furthermore, despite what is often assumed in seismic design codes, earthquakes do not usually occur as a single event, but as a series of strong aftershocks and even fore shocks. For this reason, this study investigates the effect and potential of consecutive earthquakes on the response and behavior of concrete structures. At first, six moment resisting concrete frames with 3, 5, 7, 10, 12 and 15 stories are designed and analyzed under two different records with seismic sequences from real and artificial cases. The damage states of the model frames were then measured by the Park and Ang's damage index. From the results of this investigation, it is observed that the sequences of ground motions can almost double the accumulated damage and increased response of structures. Therefore, it is certainly insufficient to ignore this effect in the design procedure of structures. Also, the use of artificial seismic sequences as design earthquake can lead to non-conservative prediction of behavior and damage of structures under real seismic sequences.

• Asian Journal of Business Environment
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• v.12 no.3
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• pp.13-22
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• 2022

Purpose: The research aims to analyze the export performance of processed seaweed, its competitiveness, and determinants on seven main destination countries. Research design, data and methodology: The study uses data of seven main destination countries of Indonesian processed seaweed from 2010 to 2019. For competitiveness analysis, the study uses Revealed Comparative Advantage, Export Product Dynamics, and X-Model of Potential Export Product. Results: The study reveals that the export performance has decreased on all five countries except for Japan and USA. The X-Model analysis shows that the market classification has increased or been stable in every country except for Germany and France. GDP per capita of each destination country and competitiveness index have positive and significance effect while other factors have negative and significance effect. Conclusions: In 2019, Indonesia's processed seaweed market in Japan, United States, and France are on potential market, while Singapore and Italy are on optimistic market. In the future, Indonesia's processed seaweed export can be focused more on countries that have a good market potential. To improve the export volume, GDP per capita of destination country, and competitiveness index of Indonesian processed seaweed should be higher, while export price, economic distance, and real exchange rate should be lower.

• Journal of Korea Trade
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• v.25 no.1
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• pp.169-183
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• 2021

Purpose - This paper analyzes the effect of the agricultural export market for Korea's new southern countries in consideration of logistics efficiency. In order to expand Korean agricultural exports, the logistics performance index, national income, per capita income, consumer price index, distance and FTA are included. Through empirical analysis, the impact of logistics efficiency on Korean agricultural exports is derived and measures are proposed to expand exports in the future. Design/methodology - The analytical model of this study takes into account the import demand factors of the new southern countries for Korean agricultural exports. A research model was established based on prior research based on the gravity model, which is widely used in international trade effect analysis. In particular, logistics efficiency measures the effect on Korean agricultural exports using the logistics performance index and examines the effect by deriving factors for export expansion. Findings - The main findings of this study can be summarized as follows: The higher the logistics efficiency of the new southern countries in exporting Korean agricultural products, the more directly they have an effect on expanding exports. In addition, it was analyzed that the expansion of Korean agricultural exports has a positive effect on the other countries' national income, per capita income, consumer price index, population, and FTA. Based on these results, the importance of efficient logistics management in agricultural exports has been emphasized. Originality/value - There are not many studies on the export of agricultural products by logistics efficiency. However, prior studies that have adapted to manufacturing and other areas suggest that logistics efficiency has a direct effect on exports. This study suggests that Korean agricultural products are directly effective in exporting to new southern countries in terms of logistics efficiency. This can be an important time point in recognizing that logistics capabilities are important to ensure new books and the safety of agricultural products.

• KIEAE Journal
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• v.16 no.2
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• pp.17-22
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• 2016

Purpose: Sensitivity analysis offers a good guideline for designing energy conscious buildings, which is fitted to a specific building configuration. Sensitivity analysis is, however, still too expensive to be a part of regular design process. The One-at-a-time (OAT) is the most common and simplest sensitivity analysis method. This study aims to propose a reasonable ground that the OAT can be an alternative method for the variance-based method in some early design scenarios, while the variance-based method is known adequate for dealing with nonlinear response and the effect of interactions between input variables, which are most cases in building energy simulations. Method: A test model representing the early design phase is built in the DOE2 energy simulations. Then sensitivity ranks between the OAT and the Variance-based methods are compared at three U.S. sites. Result: Parameters in the upper rank by the OAT do not much differ from those by the Main effect index. Considering design practices that designers would chose the most energy saving design option first, this rank similarity between two methods seems to be acceptable in the early design phase.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.89-90
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• 2010

Three post-tensioned lightweight concrete beams were tested to examine the effect of the reinforcement index on the unbonded tendon stress at ultimate strength of the beams. The reinforcement index selected for main variables were 0.06, 0.15, 0.30. Test results showed that the stress of the unbonded tendons in the ultimate strength of the post-tensioned lightweight concrete beams can be conservatively evaluated using the empirical equations specified in ACI 318-08.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.7
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• pp.4450-4458
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• 2015

The purpose of this study was to examine the influence of the exercise performance of yoga and pilates on the autonomic nervous system in an effort to provide some clinical information on exercise prescription. The subjects were 20 selected college students who majored in P.E. A yoga group and a pilates group were organized with 10 students respectively, the autonomic nervous system of the students was measured before the exercise, immediately after that and 30 minutes after recovery. The findings of the study were as follows: First, there were significant differences in the yoga group's stress index and average pulse according to the main effect of the time and interaction effect between the time and group. Second, there were significant differences in the yoga group's sympathetic nervous system activity and autonomic nerve balance according to all the main effect of the time, interaction effect between the time and group and the main effect of group. Third, there were significant differences in HRV(Heart Rate Variability), parasympathetic nervous system activity, SDNN, and RMSSD according to the main effect of the time, and interaction effect between the time and group and the main effect of group produced no statistically significant differences. In conclusion, yoga seemed to be effective at lowering stress index and average pulse. Specifically, yoga exercise seemed to exert a more positive influence on the decrease of sympathetic nervous system activity and autonomic nerve balance than pilates exercise.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.1789-1793
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• 2008

The Oxygen Index was measured for another flame retardant APP, or phosphorus, and other flame retarding assistants ZS, ZHS, AOM, and ZB, which are used as low smoke emitting materials, in order to see the increase in the flame retardation effect in comparison to the volume of additions. The results show that their flame retardation synergy effect was very small compared to the main flame retardants. The mixed use of main flame retardants, low smoking emitting materials, and phosphorus is a very important area of examination for creating synergy effect of flame retardation and lowering smoking and toxicity. For this, the results of flame retardation effect in comparison to the volume of addition of each low smoke emitting material are shown below.