• 한국통신학회논문지
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• 제15권2호
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• pp.81-87
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• 1990

상용 GPS 수신기로 일본통신연구소(CRL)와 미해군관측소(USNO)와의 시각비교를 GPS 위성 동시수신법을 이용하여 수행하였다. 상대주파수 안정도는 평균화 시간이 1일일때 1.5x$10^-13$이었다. GPS 동시수신법에 의한 시각비교결과는 LORAN-C 지상파에 의한 결과보다 정밀정확도가 10배 정도 더 높았다.

• 국제물리치료학회지
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• 제11권3호
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• pp.2147-2154
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• 2020

Background: Improperly conducted exercise may lead to worsening of musculoskeletal complications. Such may worsen due to increased repetition and intensity during exercise. In addition, different responses may show different needs for training program. Objectives: To compare kinematics of symmetric concentric and eccentric motions during increased repetitions and intensities for men and women. Design: Quasi-randomized trial. Methods: A total of ten men and eleven women participated in this study. Concentric and eccentric motions of the lateral raises were observed for initial positions of abduction and adduction. Low and high exercise intensities were applied, and 15 repetitions were conducted for both intensities. Initial, 3 inbetween repetitions, and last repetition were recorded for comparisons. Results: The concentric or abduction motions showed no significant differences for all comparisons. However, eccentric or adduction motions showed greater significant differences as the exercise intensity increased for both men and women. Such significant differences were most prevalent during the first and last repetitions with greatest differences during the initial repetitions. Conclusion: Kinematic difference between men and women during increased repetitions and intensity indicate the need for more individualized exercise intervention and consideration between men and women. Individualized interventions may prevent exercise-induced postural abnormality and corresponding musculoskeletal dysfunction.

• International Journal of Computer Science & Network Security
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• 제24권7호
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• pp.87-100
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• 2024

Modern logistics significantly influences the globalization and internationalization processes. Logistics systems are becoming increasingly important in today's rapidly changing environment. On the other hand, the development of global economic integration, business globalization contributes to the creation and development of international logistics systems and global supply chains towards the international market. The aim of the article was to investigate the national logistics systems of developing countries in the context of their integration capabilities. The main methods used in this study are statistical analysis, index, graphical and analytical methods, methods for estimating structural dynamic shifts, comparisons. Commonly used methods of economic research, as well as statistical analysis and interstate comparisons, economic modelling (trend analysis to determine the forecast level of LPI for Ukraine), etc. were also involved. It is noted that the problem of development of logistics systems in developing countries was insufficiently covered in scientific research. The study suggests that the integration capabilities of national logistics systems are determined by the logistics performance of each country and the favourable logistics environment for integration transformations. This allowed analysing the state of the logistics systems of Poland, Bulgaria, India and Ukraine, and identifying the factors that determine it. The logistics environment of Poland, Bulgaria, India and Ukraine, as well as the factors of its formation are evaluated. The components of the logistic portrait of the country in the context of integration capabilities of the logistic system are offered. Trend analysis of LPI was carried out on the example of Ukraine, which showed positive trends in the logistics system and allowed drawing conclusions about increasing integration into international logistics channels based on its geopolitical location, improving the characteristics of the logistics environment, including customs regulation, and improving the efficiency of the national logistics system. Prospects for further research involve studies of the impact of pandemics, globalization, digitalization on logistics systems, including that of developing countries.

• 유통과학연구
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• 제13권9호
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• pp.19-27
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• 2015

Purpose - In a global economy, marketers are required to understand service quality from an international consumer viewpoint. Despite the increased need for cross-cultural research, few studies have developed service quality research international in scope. The present research aims to shed light on variations in airline service quality among international consumers. Research design, data, and methodology - Conducting crosscultural research, this study compares airline service quality variations, investigating an international consumer group and a Korean consumer group. T-test and factor analyses are applied to examine mean scores and factor structure of the airline service dimensions. Results - The results indicate there are significant differences in mean comparisons between the groups. The international consumers indicate significantly higher service perception scores than the Koreans. Further, we find that the factor structure of airline service quality diverges between the groups. The international group considers airline service quality in four dimensions, while Koreans consider it in two. Conclusions - The study sheds new light on international service variations and suggests that the field of airline service quality may differ by nations and/or cultures.

• Wind and Structures
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• 제34권2호
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• pp.231-257
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• 2022

Transmission lines systems are important components of the electrical power infrastructure. However, these systems are vulnerable to damage from high wind events such as hurricanes. This study presents the results from a 1:50 scale aeroelastic model of a multi-span transmission lines system subjected to simulated hurricane winds. The transmission lines system considered in this study consists of three lattice towers, four spans of conductors and two end-frames. The aeroelastic tests were conducted at the NSF NHERI Wall of Wind Experimental Facility (WOW EF) at the Florida International University (FIU). A horizontal distortion scaling technique was used in order to fit the entire model on the WOW turntable. The system was tested at various wind speeds ranging from 35 m/s to 78 m/s (equivalent full-scale speeds) for varying wind directions. A system identification (SID) technique was used to evaluate experimental-based along-wind aerodynamic damping coefficients and compare with their theoretical counterparts. Comparisons were done for two aeroelastic models: (i) a self-supported lattice tower, and (ii) a multi-span transmission lines system. A buffeting analysis was conducted to estimate the response of the conductors and compare it to measured experimental values. The responses of the single lattice tower and the multi-span transmission lines system were compared. The coupling effects seem to drastically change the aerodynamic damping of the system, compared to the single lattice tower case. The estimation of the drag forces on the conductors are in good agreement with their experimental counterparts. The incorporation of the change in turbulence intensity along the height of the towers appears to better estimate the response of the transmission tower, in comparison with previous methods which assumed constant turbulence intensity. Dynamic amplification factors and gust effect factors were computed, and comparisons were made with code specific values. The resonance contribution is shown to reach a maximum of 18% and 30% of the peak response of the stand-alone tower and entire system, respectively.

• 한국항해학회지
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• 제15권1호
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• pp.95-110
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• 1991

This paper aims to investigated the origins and characteristics of flags of convenience(FOC) with International Ship Register(ISR), which was recently adopted by a few Western Europe countries(for example, Norway, U.K., France) and to compare FOC with ISR in terms of shipping policy, ship management, and expenses, and tax policy.

• International Journal of Naval Architecture and Ocean Engineering
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• 제6권4호
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• pp.1197-1208
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• 2014

The problem of the oblique water entry of a three dimensional body is considered. Wagner theory is the theoretical framework. Applications are discussed for an elliptic paraboloid entering an initially flat free surface. A dedicated experimental campaign yields a data base for comparisons. In the present analysis, pressure, force and dynamics of the wetted surface expansion are assessed.

• 국제물리치료학회지
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• 제10권3호
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• pp.1834-1839
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• 2019

Background: Lumbar lordosis is a result of muscle shortening and may cause low back pain. Objective: To examine the effects of static and dynamic stretching on lumbar lordosis and low back pain in university students. Stretching is an intervention that can be applied to shortened muscles; however, very few studies have compared the effects of static and dynamic stretching on lumbar lordosis and low back pain. Design: Randomized controlled clinical trial (single-blind) Methods: The 12 selected subjects were randomly assigned static stretching and dynamic stretching groups each containing six students. The subjects in each group performed their respective stretching programs for 17 minutes, 3 times a week for 4 weeks. Lumbar lordotic angle, low back pain, and Oswestry Disability Index (ODI) were measured before and after the intervention. Results: Intragroup comparisons showed significant reductions in lumbar lordotic angle and low back pain in the static stretching group while the dynamic stretching group showed significant decreases in lumbar lordotic angle, low back pain, and ODI. The intergroup comparisons showed significantly greater differences between pre- and post-intervention in lumbar lordotic angle and low back pain in the dynamic stretching group compared to those in the static stretching group while ODI did not show any intergroup difference. Conclusions: The results of this study indicated that, while both static and dynamic stretching helped to reduce the lumbar lordotic angle and low back pain, dynamic stretching was more effective in alleviating lumbar lordotic angle and low back pain compared to static stretching.

• 국제물리치료학회지
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• 제9권4호
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• pp.1576-1585
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• 2018

Regularly participating in physical activity is known to improve quality of life and body composition in elderly with stroke. However, comparatively less physical activity is performed by the stroke survivors. The factors related to inactivity in elderly female stroke survivors have not been elucidated. Therefore, this study aims to compare the quality of life factors and limb compositions between the active and inactive elderly female stroke survivors. Forty nine subjects between the ages of 65 to 75 years were selected from the KNHANES data between the years 2009 to 2011. In addition, 186 agematched healthy peers were also selected for limb composition comparisons. The subjects were groups based on walking days per week: walkers; 3 days or more, non-walkers; less than 3 days per week. BMI and waist circumference were within the obesity ranges for both the non-walkers and walkers. As results, the trend for greater fat (${\pm}10%$) and lean mass (${\pm}30%$) differences were observed for non-walker and walkers, respectively. Significantly greater reasons for function limitation by stroke and hypertension were reported with significantly greater self-care difficulty was shown by the walkers. In conclusion, elderly female stroke survivals may require customized motivation and continuous support to participate in physical activity regularly.

• International Journal of Computer Science & Network Security
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• 제22권12호
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• pp.197-204
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• 2022

Sorting is an important data structure in many applications in the real world. Several sorting algorithms are currently in use for searching and other operations. Sorting algorithms rearrange the elements of an array or list based on the elements' comparison operators. The comparison operator is used in the accurate data structure to establish the new order of elements. This report analyzes and compares the time complexity and running time theoretically and experimentally of insertion, merge, and heap sort algorithms. Java language is used by the NetBeans tool to implement the code of the algorithms. The results show that when dealing with sorted elements, insertion sort has a faster running time than merge and heap algorithms. When it comes to dealing with a large number of elements, it is better to use the merge sort. For the number of comparisons for each algorithm, the insertion sort has the highest number of comparisons.