• Journal of the Korean Physical Society
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• 제73권10호
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• pp.1410-1419
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• 2018

A skier's motion was analyzed by a simple model consist of point mass m and a single rod connected to a single ski plate. We studied the conditions for the stable ski turn as functions of the linear velocity and the radius of the turn. The solutions for the stable ski turn in our model do not require any extra skier's movement to complete a stable circular turn. The solution may then give the skier the most comfortable skiing method without any active movement to control the ski. The generalized force supporting the point mass from the ski plate was calculated. We obtained the force from the ground (rebound force) without any geometrical structure of the ski plate. Adding an active movement to the direction of the ski plate, the conditions for the stable ski turn were also analyzed. Our result gives some insight for the skier who wants to develop technique.

• 물과 미래
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• 제8권2호
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• pp.56-60
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• 1975

Traditional descriptions of water movement in soils and of calculations of infiltration rates neglect the air movement and its compressibility. The movement of two fluids in the bounded layered porous medium is treated analytically and computer simulations are conducted for given boundary conditions and initial saturation profiles. The movement of a given saturation across the interface between the different soil layers is theoretically developed by considering the conservation of mass. It is shown that the existence of the interface affects the infiltration rate when the average total velocity is greater than zero. The transition from one layer to another layer cause a change in the capillary drive and consequently influences the infiltration rate.

• 한국지형학회지
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• 제18권2호
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• pp.25-37
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• 2011

본 연구의 목적은 충남 매곡천 최상류 차암골 유역(이하 조사유역)에 있어서 홀로세 동안 유역을 둘러싸고 있는 구릉사면의 삭박에 의해 사면에서 기원한 무기물질이 곡저로 이동하는 현상(이하 사면물질이동)의 이력을 구명하는 것이다. 이를 위하여 조사유역의 곡저에 분포하는 충적층을 대상으로 층상해석·탄소연대측정·입도분석을 실시하고 그리고 조사유역의 지형분석도 병행했다. 그 결과는 다음과 같다. 약 9,100yrBP~최근에 걸쳐서 10²~10³년의 시간 규모(time scale)로 발생한 수 회의 사면물질이동으로 인하여 다량의 무기물질이 조사유역의 곡저에 형성되어 있는 습지기원의 유기물층에 혼입되었거나 또는 유기물층 사이에 협재되어 있는 것으로 확인되었다. 조사유역에서 홀로세 초기 이후 사면의 불안정시기에 발생했던 사면물질이동은 최소 8회(M₁기(期)~M₈기(期)) 그리고 사면의 안정기에 형성되는 습지환경은 총 4회(W₁기(期)~W₄기(期))가 존재했던 것으로 밝혀졌다. 본 분석결과는 향후 매곡천 유역의 홀로세 기후변화와 이에 따른 유역을 구성하고 있는 구릉사면의 삭박과정을 복원하는 데 기초자료로 활용될 것이다.

• 철학연구
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• 제144권
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• pp.141-166
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• 2017

아도르노가 대중운동에서 가장 중요하게 비판하고 있는 지점은 혁명 지도자와 추종자의 동일성이다. 그 동일화 작업은 세 가지의 특징을 가진다. 첫 번째 특징은 실제의 적대자보다 더 한 이미지를 만들어 적과 동지의 구분을 확실하게 해 집단 내에 연대감을 조성하는 것이다. 이렇게 연대감에 의해 조성된 대중 안에서 저항하는 개별적 주체들은 사라지고 집단과 동일화된 주체만이 존재하게 된다. 두 번째 특징은 낙관주의적인 유토피아를 제시해 대중이 초월적 가치로부터 구원이 도래한다고 믿게 만드는 것이다. 또한 이러한 대중운동은 본인이 속한 연대에 어긋난다고 여겨지는 다른 집단이나 사람들에 대해 논의 과정 없이 비난하는 데에 그친다. 세 번째 특징은 나르시시즘을 기반으로 한 대중 최면상태를 통해 개별적 주체가 사라진 대중이 지휘자들과 동일화 되어 다른 주체들에게 자신이 걸린 최면상태를 강요하는 것이다. 본 논문의 목적은 아도르노가 대중운동의 파시즘적인 폭력에 대해 어떻게 비판하고 있는지 살펴보고 대중운동의 과제에 대해 어떤 것을 제시하고 있는지 분석하는 것이다.

• 한국정밀공학회지
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• 제16권4호통권97호
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• pp.213-219
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• 1999

Piezoelectric element is deformed by driving voltage pattern. We developed a device of moving LD(laser disk) to use the rapid deformation of piezoelectric element. If driving voltage is changed very rapidly, the difference of acceleration is accurred between spindle motor and LD. To move LD on turn table is attained by utilizing difference of acceleration. This paper describes theoretical and experimental results about the movement of LD and presents to measure the center of mass LD with unbalance force.

• 수완나부미
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• 제6권2호
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• pp.85-106
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• 2014

Protests are not new in Malaysia, though it is restricted by the ruling government. The trend of street protests and demonstrations since the emergence of Coalition for Clean and Fair Elections (Bersih), Malaysia's first people movement on electoral reform, has triggered a sentiment of people power among Malaysian citizens. With protests and popular mobilization becoming pronounced in Malaysian politics, political activism becomes for Malaysians a channel of discontent and expression of political preferences. Using information obtained from interviews with individuals linked to the movement, this paper articulates that protests are no longer exclusive to Malaysians. This paper illustrates the emergence of the Bersih movement and explores the three Bersih mass rallies that took place in 2007, 2011, and 2012. This paper further links the protests with the electoral reform initiatives. It argues that the Bersih movement has managed to lobby fundamental changes in the Malaysian political culture.

• 한국전문물리치료학회지
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• 제27권2호
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• pp.155-161
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• 2020

Background: The consequences of falls are often debilitating, and prevention is important. In theory, the lower the center of mass (COM), the greater postural stability during standing, and a weight belt at the waist level may help to lower the COM and improve the standing balance. Objects: We examined how the limit of stability (LOS) was affected by the lowered center of mass with the weight belt. Methods: Twenty healthy individuals participated in the LOS test. After calculating each participant's COM, a weight belt was fastened ten centimeters below the COM. Trials were acquired with five weight belt conditions: 0%, 2%, 4%, 6%, and 8% of body weight. Outcome measures included reaction time, movement velocity, endpoint excursion, maximum excursion, and directional control in 4 cardinal moving directions. Results: None of our outcome variables were associated with a weight belt (p > 0.075), but all of them were associated with moving direction (p < 0.01). On average, movement velocity of the COM and maximum excursion were 31% and 18% greater, respectively, in mediolateral than anteroposterior direction (5.4°/s vs. 4.1°/s; 97.5% vs. 82.6%). Conclusion: Our results suggest that postural stability was not affected by the weight-induced lowered COM, informing the development and improvement of balance training strategies.

• 한국운동역학회지
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• 제21권2호
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• pp.181-187
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• 2011

The purpose of this study was to identify major factors on pirouette in ballet, and especially angle, Center of Mass(CM) & muscle activity aspects. The data were collected by using Motion Analysis System with 12 cameras to analyze kinematic variables with 120 Hz and Electromyography(EMG; 4,000 Hz) & Force Platform(1,000 Hz) to analyze kinetic variables. The subjects of this study were 8 female ballet dancers. The results as follow. First of all, full extension of knee joint and full plantar flexion of ankle joint appeared at the similar point. Secondly, in the rotational phase, total movement of segments in Good motion is smaller than that of Bad motion(in Good motion, head movement 2.70 cm, right shoulder movement 0.72 cm, left shoulder 4.26 cm, left wrist 17.4 mm smaller than Bad motion). Third, CoP distance of Good motion is 11.76 mm, and CoP distance of Bad motion is 11.76 mm, so Good motion is 5.98 mm smaller). Lastly, Pirouette need more retus femur activity than gastrocnemius activity in extention phase and rotation phase of support leg.

• 한국환경과학회지
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• 제21권3호
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• pp.327-337
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• 2012

Air pollution inventories are aggregated around south-eastern part of the Korean Peninsular including Busan, Ulsan, and Changwon cities. Because densely populated cities are concentrated in this region, air pollutants emitted from one of these cities tend to be impacted on the air quality of other cities. In order to clarify the seasonal movement pattern of emitted particles, several numerical simulations using WRF/FLEXPART were carried out. Four cases were selected for each season. The Weather Research and Forecasting model (WRF) reproduced atmospheric flow fields with nested grids. The seasonal pattern of air mass of study area was determined by backward and forward trajectories. As a result, the air parcel moves from northwest to southeast due to northwesterly winds in spring and winter. Also air parcel transports from south to north in summer, and moves from west to east. Because the air mass moves differently in each season, these characteristics should be considered when performing air quality analysis.

• 복식
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• 제52권6호
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• pp.165-179
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• 2002

This paper begins with the thesis that the so-called 'Be Slow' Movement has not only affected the contemporary life style but also the current fashion trend in the West as well as in Korea. The influence of the 'Be Slow' Movement on the everyday life of Western and Korean society can be documented by recent books, news reports, and many articles from various kinds of mass media and fashion magazines since the year 2000. The results of this study can be summarized as follows. First. the 'Be Slow' Movement is a new cultural phenomenon and very different from that of the past century. It has emerged very recently and it could affect the life style o( its followers for a long period of time. Second, the influence of 'Be Slow' Movement on everyday life can be witnessed in many behavioral choices. such as the preference of organic food and natural cooking for food and the preference of rural life and a green patch of land for housing. Some aspects of the way of rearing the children and long-term planning of one's life are also under the influence of 'Be Slow' Movement. In a way. the life style Proposed by the 'Be Slow' Movement is somewhat similar to that of 'Bobos'. Third, the influence of 'Be Slow' Movement on the current fashion trend can be observed in the appreciation of time-consuming labour and increased usage of D.I.Y. clothing. The higher value of fashion goods with handcrafted part or scarce luxury item are good examples of the influence by the 'Be Slow' Movement. One can say that the 'Be Slow' Movement is not retrogression, but a re-creation of time and space to be grateful for one's life. Thus, it is not anti-technology but a commercialism with technology in order to enhance the quality of life and to place people in the center of production and consumption. Consequently, one may say that the 'Be Slow' Movement is a appropriate and affluent way of living.