• Journal of information and communication convergence engineering
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• 제4권4호
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• pp.141-146
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• 2006

In these days, wireless data services are becoming ubiquitous in our daily life because they offers several fundamental benefits including user mobility, rapid installation, flexibility, and scalability. Moreover, the requests for various multimedia services and the Quality of Service (QoS) support have been one of key issues in wireless data communications. Therefore the research relative to Medium Access Control (MAC) has been progressing rapidly. Especially a number of QoS-aware MAC schemes have been introduced to extend the legacy IEEE 802.11 MAC protocol which has not guaranteed any service differentiation. However, none of those schemes fulfill both QoS features and channel efficiency although these support the service differentiation based on priority. Therefore this paper studies a novel MAC scheme, referred to as Enhanced Distributed Coordination Function with Network Adaptation (EDCF-NA), for enhancements of both QoS and medium efficiency. It uses a smart factor denoted by ACK rate and Network Load Threshold (TH). In this paper, we study how the value of TH has effect on MAC performance and how the use of optimal TH pair improves the overall MAC performance in terms of the QoS, channel utilization, collision rate, and fairness. In addition, we evaluate and compare both the performance of EDCF-NA depending on several pairs of TH and the achievement of various MAC protocols through simulations by using Network Simulator-2 (NS-2).

• 대한임베디드공학회논문지
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• 제7권5호
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• pp.227-239
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• 2012

Recent advances in electronics have enabled various conventional products to incorporate with numerous powerful microcontroller. Generally, an embedded system is a computer system designed for specific control functions within a larger system, often with real-time computing constraints. The growing performance and reliability of hardware components and the possibilities brought by various design method enabled implementing complex functions that improve the comport of the system's occupant as well as their safety. A cyber physical system (CPS) is a system featuring a tight combination of, and coordination between, the system's computational and physical elements. The concept of cyber physical system, including physical elements, cyber elements, and shared networks, has been introduced due to two general reasons: design flexibility and reliability. This paper presents a cyber physical system where system components are connected to a shared network, and control functions are divided into small tasks that are distributed over a number of embedded controllers with limited computing capacity. In order to demonstrate the effectiveness of cyber physical system, an unmanned forklift with autonomous obstacle avoidance ability is implemented and its performance is experimentally evaluated.

• 한국의류학회지
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• 제42권1호
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• pp.121-132
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• 2018

Recent beauty trends focus on suitability to individual features. A personal color system is a recent aesthetic concept that influences color make up and coordination. However, a personal color concept has several weaknesses. For example, type classification is qualitative and not quantitative because its measuring system is a sensory test with no industry standard of personal color system. A quantitative personal color type classification model is the purpose of this study, which can be a solution to above problems. This model is a kind of mapping system in a 3D Cartesian coordinate system which has own axes, Value, Saturation, and Yellowness. The cheek color of the individual sample is also independent variable and personal color type is a dependent variable. In order to construct the model, this study conducted a colorimetric survey on a 993 sampling frequency of Korean women in their 20s and 30s. The significance of this study is as follows. First, through this study, personal color system is established on quantitative color space; in addition, the model has flexibility and scalability because it consisted of independent axis that allows for the inclusion of any other critical variable in the form of variable axis.

• PNF and Movement
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• 제5권1호
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• pp.29-35
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• 2007

Purpose : The purpose of this study was investigated to find the approach in the PNF and TC for frail elder Method : This is a literature study with books, articles, seminal note and books for PNF and TC international course. Result : Neural mechanisms contribute significantly to the gains that occur in the range of motion about a joint with stretching exercises. The participation in a stretch-training program decreases tonic reflex activity and increases flexibility and decreases in force production and muscle activation. Also the stretching-induced decreases may be due to a central nervous system inhibitory mechanism. PNF stretch techniques can increase ROM in older adults. These results may differ from those of studies performed with younger populations because of age-related physiologic changes. TC exercise improves balance control and muscle strength and were associated with reorganized lower extremity neuromuscular patterns. Conclusions : The stretch training program of the PNF and TC contribute to increase the balance and coordination for frail elder. Therefore, The frail elder prevent falling. Further study, The PNF and TC be introduced as the new therapeutic intervention for frail elder.

• 유통과학연구
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• 제18권12호
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• pp.45-54
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• 2020

Purpose: Indonesia's maritime logistics and distribution system is currently faced with several challenges, some of which include prolonged export and import time for goods handling as well as the high logistics cost. This study further analyzes the existing business processes in maritime logistics in East Java Province in order to provide solutions to the challenges. Research design, data and methodology: This research was carried out in East Java Province, Indonesia, with data collected through field observations, documentation, and in-depth interviews with all the stakeholders involved. Results: The study showed that the number of stakeholders and activities involved in the flow of goods movement ultimately impacted the length of time. These factors can be classified into the following five: 1) export and import regulations, 2) third party logistics competencies, 3) transportation infrastructure and facilities, 4) adoption of information systems and technology, and 5) maritime line connectivity. Conclusion: Analyzing the three supply chain flows in the maritime logistics and distribution industry called for the need for improvement to increase coordination among related institutions, improve the flexibility of dwelling time to the conditions of each port, enhance service levels, improve transportation infrastructure and facilities, implement information system and technology, and develop shipping routes and networks. Therefore, a collaborative supply chain management system can be realized.

• 대한통합의학회지
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• 제10권3호
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• pp.85-94
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• 2022

Purpose : This study aimed to investigate the effects of 12 weeks of resistance exercise on body composition, physical strength, blood lipids, and insulin. Methods : The study was conducted on 24 elderly women divided into two groups: 12 subjects in an exercise group and 12 subjects in a control group. Resistance exercise was performed for 50 minutes a day, three times a week, for the duration of 12 weeks, and body composition, physical strength, blood lipids, and insulin were measured before and after the subjects completed the program. For the statistical analysis, the mean and standard deviation (M±SD) of each variable were calculated using SPSS version 20, and a paired t-test and two-way repeated ANOVA were conducted to test for the differences before and after the resistance exercise. All significant levels were set to α=.05 as a result of the experiment. Results : Changes in body composition after the 12-week resistance exercise program did not show any significant difference based on the comparison between the groups, but when noting the values for body fat percentage and body in the control group before and after, a significant difference was shown in fat mass (p<.05). As for changes in physical fitness, significant differences appeared in flexibility, muscle strength, and stenotic force (p<.01) when the groups were compared. Regarding pre- and post-values within each group concerning flexibility within the exercise group, significant differences were shown in gender (p<.001), muscle strength (p<.05), (p<.01), muscle earth strength, equilibrium (p<.01), stenosis force, and cardiopulmonary earth force (p<.001). Also, comparisons between populations in changes in blood lipids the values before and after in each group, significant differences in glucose (p<.05) and insulin (p<.05) were shown in the exercise group. When comparing the values before and after in each population, a significant difference was shown in the control group (p<.05). Conclusion : When all the results were integrated, the 12-week resistance exercise program was found to enhance physical strength (flexibility, muscle strength, and coordination) and improve the blood sugar levels of elderly women. In particular, resistance exercise is believed to lower the prevalence of obesity, type 2 diabetes mellitus, and metabolic diseases by having a positive effect on insulin. Further studies are suggested to verify the effect on body composition and blood lipids by setting up a variety of exercise treatment methods (including subjects, exercise periods, exercise plans, and exercise intensity focuses).

• 항공우주정책ㆍ법학회지
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• 제31권2호
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• pp.99-143
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• 2016

General aviation and air transport are two wings of the civil aviation industry. Chinese air transport is developing rapidly, and has become the world second air transport system only second to US since 2005. However, Chinese civil aviation is far behind the world average level, and cannot meet requirements of economic construction and social development. The transition and structural adjustment of Chinese economy provide the general aviation with a unprecedented broad market. The prospect of general aviation is promising and anticipated. The development of general aviation industry needs the legislative supports, and the current legislative conditions of Chinese general aviation are undoubtedly far behind the realistic requirements. Accelerating the legislation in Chinese general aviation industry requires scientific legislation concept. First, Legislation must promote development of general aviation industry. The general aviation will serves as a Chinese emerging industry that boosts domestic demand, promotes employment and expedite domestic economic development. We should, based on both the concept of promoting the industrial development of general aviation and national industrial planning, enact and rectify relative laws and regulations. And we should also straighten out the relationship between aviation security and industrial development and promote the revolution of low-altitude airspace management in an all-round way, in order to improve the utilization rate of airspace resources, classify and establish airspace, simplify examination and approval procedure and intensify operation management. In addition, what we should do is to expedite the infrastructure layout construction, guide the differentiated but coordinated development of general aviation industries in various areas, establish a united supervision mechanism of general aviation, redistrict the responsibilities of Chinese Air Control Agency and set up legislation, law enforcement and judicial systems with clarified institutions, clear positioning and classified responsibilities, so as to usher in a new era of the legislative management of Chinese general aviation industry. Second, shift the focus from regulations to both regulations and services. Considering the particularity of the general aviation, we should use American practices for reference and take into account both regulation and service functions when enacting general aviation laws. For example, we should reduce administrative licensing and market supervision, and adopt "criteria" and "approval" management systems for non-commercial and commercial aviation. Furthermore, pay attention to social benefits. Complete social rescuing mechanism through legislation. It should be clarified in legislation that general aviation operators should take the responsibilities of, and ensure to realize social benefits of environmental protection and ecological balance .Finally, rise in line with international standards. Modify Chinese regulations which is inconsistent with international ones to remove barriers to international cooperation. Specify basic legislative principles. One is the principle of coordination. Realize coordination between the civil aviation and general aviation, between military aviation and civil aviation, and among departments. Two is the principle of pertinence. The general aviation has its own rules and specialties, needing to be standardized using specialized laws and regulations. Three is the principle of efficiency. To realize time and space values of general aviation, we should complete rules in aerospace openness, general aviation airport construction, general aviation operations, and regulation enforcement. Four is the principle of security. Balance the maximum use of resources of Chinese airspace and the according potential threats to Chinese national interests and social security, and establish a complete insurance system which functions as security defense and indemnificatory measure. Establish a unified legal system. Currently, the system of Chinese general aviation laws consists of national legislation, administrative laws and regulations and civil aviation regulations (CAR). Some problems exist in three components of the system, including too general content, unclear guarantee measures, incomplete implementation details, and lacking corresponding pertinence and flexibility required by general aviation regulations, stringency of operation management and standards, and uniformity of standards. A law and regulation system, centered on laws and consisting of administrative laws regulations, industrial regulations, implementation details, industrial policies and local laws and regulations, should be established. It is suggested to modify the Civil Aviation Law to make general aviation laws complete, enact the Regulations of General Aviation Development, and accelerate the establishment, modification and abolition of Chinese general aviation laws to intensify the coordination and uniformity of regulations.

• 한국융합학회논문지
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• 제13권4호
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• pp.625-634
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• 2022

이 연구의 목적은 지역에 거주하는 65세 이상 노인의 신체 활동(physical activity; PA) 수준과 활동 체력(functional fitness; FF) 변인 사이의 관계를 조사하는 것이었다. 피검자(남성:1,645명; 여성:2,394명)의 PA 수준은 설문지를 이용하여 조사하였고, FF는 상·하지 근력, 민첩성 및 동적 평형성, 유연성, 유산소성 능력, 협응력, 그리고 신체 구성 등 체력 영역을 대표하는 6항목으로 측정, 평가하였다. 피검자는 신체 활동 권장기준에 따라 권장량보다 낮은 그룹(low physical activity; LPA)과 권장량 기준을 충족하는 그룹(PA)으로 나누었고, PA 그룹은 다시 강도 수준에 따라 중강도 그룹(MIPA)과 고강도 그룹(HIPA)으로 분류하였다. 권장량 수준을 충족하는 피검자는 48%였고, 이들은 모든 항목에서 LPA보다 성적이 높았다(p<.001). HIPA 그룹은 MIPA 그룹보다 민첩성 및 동적 평형성, 협응력, 그리고 하지 근력(여성)이 유의하게 높았다(p<.001). 결론적으로 지역에 거주하고 있는 노인이 활동 체력을 유지하고 개선하기 위해서는 건강을 위해 권장하고 있는 신체 활동량을 충족시켜야 하며, 특히 낙상 관련 체력을 개선하기 위해서는 강도가 높은 신체 활동을 할 필요가 있다.

• 한국의류학회지
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• 제21권2호
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• pp.286-291
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• 1997

The purpose of this study is to examine the effect of clothing habits wearing cool or warm in daily life on motor ability. A group of ten healthy young females were divided into a cold (C) group and a warm (W) group. From autumn to winter, C group was advised to wear cool clothing, and W group, warm Clothing. The subject's physical fitness were tested in October, initial stage of the clothing training and March of the following year, final stage of the training. The measurements were taken after the subjects rested in a thermoneutral room conditioned at 23$\pm$2$^{\circ}C$ over 1 hour. The test items were weight, skinfold thickness, grip strength (right, left), back-lift strength, vertical jump, sit-ups, Irosmax, side step test, single-foot standing test with eyes closed, and standing trunk flexion. Changes in motor ability of each group between initial stage and final stage of the training were compared. 1. Muscle strength, part of the motor revelation capacity, showed no significant change in the both ,Troops. On the other hand, strength and power showed a decrease in the both groups and C group showed a sharp decrease. 2. Muscular endurance and cardio-pulmonary fitness, part of the motor continuation capacity, were increased after the training and the degree of increase was great in C group. 3. C group showed significant increase in motor coordination capacity including agility, balance, and flexibility after the training, while Wgroup showed significant increases only in balance. 4. Weight and skinfold thickness as a part of the physique showed no significant change.

• 한국의류학회지
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• 제29권1호
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• pp.79-90
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• 2005

The purpose of this study is to find out the wearing conditions and cause of discomfort with shoes for male college students which will provide useful information fur the shoes manufacturer. The questionnaire survey was conducted on 346 male college students on purchasing practices, wearing conditions, and overall satisfaction with shoes. The results were as follows: Male college students have a tendency to have longer buying cycles and buy more expensive shoes compare to high school students. The order of criteria considered fer purchasing was shape, price, style coordination with clothing. The order of criteria considered for purchasing differed according to their major, economic status and purchasing place. Most of them have two pairs of white or black sports shoes and one pair of either black or brown dress shoes. The most popular material was man made leather but college students have more leather shoes than high school students. There were differences between high school students and college students in wearing conditions, how many they have, material and color. The varieties of shoes differed by season. They were satisfied with their shoes' design and color but unsatisfied with qualify or the material and durability of the shoes. Due to the pressure of the shoes, they experienced discomfort such as numbness, blisters on the feet and red skin. They experienced discomfort on the soles of the feet. The causes of discomfort were shape, width, hight of the heel, material and length in order. Dress shoes cause more discomfort than sport shoes due to the hardness of material, and flexibility of the sole. Since the material differed by the price, the degree of discomfort significantly differed by price too.