• The Transactions of the Korean Institute of Power Electronics
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• v.4 no.6
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• pp.554-560
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• 1999

In this paper, a vibration suppression method using an energy stored in winding inductance and an induced v voltage of the Linear Stepping Motor(LSM) is shown, and it is applied to a new one-phase excitation method A And a magnetic equivalent circuit is based on the structure of the LSM, and then the electric equivalent circuit of the LSM is derived by solving equations for the magnetic equivalent circuit. Several dynamic characteristics of the LSM are analyzed by the ACSL with the voltage equations, the force equations and the kinetic equation, a and are measured by experimental system.

• Journal of Korean Society of Water and Wastewater
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• v.30 no.6
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• pp.699-705
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• 2016

Although it has been well known that the Saemaul Undong had a direct relation with the water resources development during 1970's, its contribution to the water resources and increased income in rural communities has not been thoroughly quantified so far. In order to assess the contribution of the Saemaul Undong in terms of rural water resources development, we investigated various historical data produced by the central and local governments in relation to water resources development. The results show the direct and indirect contribution of the Saemaul Undong to the water resources development in rural communities such as sewage works, water supply facilities, shared wells, and river works. The results also showed a positive relation between per-house income in rural communities and areas of irrigated paddies, which were rapidly increased during 1970's. These results can be utilized to transplant the positive aspect of the Saemaul Undong to developing countries focusing on water resources development in rural areas.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.12 no.1
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• pp.15-20
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• 2005

Purpose: This study was done to compare of adult body composition and body image before and after regular exercise program at a sports center. Method: The participants were 32 adults who were beginning regular exercise at a sports center in D city. The body composition was measured by body weight, soft lean mass, fat mass, percent body fat, fat distribution, degree of obesity and BMI, using the Inbody 3.0. Body image. Data were collected using structured questionnaires and analyzed using paired t-test. Results: 1. Significant improvement was shown in body composition. 2. The score for body image increased after the program, but the change was not statistically significant. Conclusion: The short-term exercise program was very effective in improving body composition, but changes in the evaluation of body image need long-term exercise. Also, we were concluded that it is very important to consider preference level when evaluating body composition and body image.

• Journal of Ocean Engineering and Technology
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• v.30 no.5
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• pp.361-366
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• 2016

The aim of this study was to experimentally investigate the hydrodynamic performance of a hemispheric wave energy converter (WEC) and its wave power takeoff. The WEC is a heaving body-type point absorber with a hydraulic-pump power take-off (PTO) system. The hydraulic PTO system consists of a hydraulic cylinder, hydraulic motor, and generator, with consideration given to the hydraulic pressure and flow rate. Two body model shapes, including the original hemisphere and a bottom-chopped hemisphere, were considered. The heave RAOs of the two models were evaluated for various body drafts. The effects of the hydraulic PTO system on the RAOs were also investigated.

• Journal of the Daesoon Academy of Sciences
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• v.25_1
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• pp.189-229
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• 2015

동아시아의 19세기는 근대화 물결 안에서 변화의 시대였다. 중국, 한국, 일본은 식민지적 압박가운데 정치적 위기를 대면하였고 선진 문물과 기독교는 사회, 문화, 종교, 사상의 변화를 가져왔다. 신종교운동도 각 나라에서 다양한 형태와 철학으로 등장하였다. 이들의 근본적인 사상은 일반적으로 불교, 유교, 도교, 신교, 샤머니즘과 연관되어 있었다. 근대한국이 정치적 혼란을 겪을 때 여러 신종교들이 1860년을 전후로 나타났다. 나중에 천도교가 된 동학, 증산계, 대종교, 원불교 가운데 증산계 계통의 대순진리회는 사회-종교적인 영향력 차원에서 한국에서 가장 성공적인 신종교 운동이다. 그들은 상제가 스스로 구천에서 혼탁한 삼계를 회복하기 위해 직적 내려왔음을 따르고 있다. 그렇다면, 구천상제에 대한 가르침이 어떻게 이해되고 있을까? 대순진리회의 근본적인 우주관은 무엇일까? 또, 이것이 일본의 유명한 천리교와 중국(대만)의 대규모 일관도와 어떻게 구분될까? 이 논문은 청계탑의 상직적인 콘셉트 안에서 대순의 상제관과 우주관의 관계를 이해하고자 대순의 경전격인 전경, 현무경, 예화들인 심우도, 사신도, 12지신도 등을 탐구할 것이면 이 한국의 대표적인 신종교의 우주관을 천지공사와 후천의 가르침과 연관하여 논리적으로 접근해석 할 것이다.

• Journal of Science and Technology Studies
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• v.18 no.2
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• pp.95-133
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• 2018

Since the beginning of the millennium, 'Maker Movement' has been active throughout the world. Today, there is a maker fair every year in major cities of the world including Seoul, and the number of attendees is increasing day by day, so it can be seen as a kind of maker 'phenomenon'. The positive implication of the maker's movement is that it attempts to break down the monopoly of manufacturing and to restore the rights and capabilities of citizens as makers. Today, highly developed industrial capitalism has a tendency to structurally paralyse citizens, to tie their hands and feet, and to degenerate into consuming entities only. Therefore, it can be said that the maker movement has structural tensions in the relationship of neoliberal manufacturing culture. This study is an attempt to actively interpret the maker movement in terms of "critical making". The maker movement can trace its origins to "counterculture" and "new communalism" that emerged in the United States in the 1960s and 1970s. On the other hand, there is criticism that the maker movement can fall into another technology utopianism and function as an area of consumer society, and mobilize it in the direction of activating consumerism. Although the maker's movement is amorphous due to its characteristics and it is currently in progress, it is difficult to make crude definition yet. However, as the citizens who have been defined only as consumers of science and technology, are newly emerging as producers of makers, there have been great changes in the topography of science and technology and civil society. So the scientific implication of the maker movement is great in that it shows the possibility of causing it.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.4 no.1
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• pp.53-61
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• 2010

In this paper, We investigated the characteristic analysis of flexibility and muscle strength for exercise to verify capacity in rehabilitation exercise of lumbar using lumbar strengthen exercise instrument. We have experiment in 20th years man and woman who are 20 subject with no medical history, we divided subjects into control group with no exercise and training group with lumbar strengthen exercise. We used Hi-Spine(Medicalscience.korea) also, provided exercise 40 minute a day, three days a week and progressed total four weeks. Moreover in our experiment, subjects exercised four postural position as lay down, sit, stand and stretch each ten minute. We measured trunk extension backward, trunk flexion forward, evaluation of based physical fitness and lumbar joint torque. The reults have shown that there more improved all for flexibility, based physical fitness and lumbar joint torque in training group than control group. We indicated that by rotating 3-D axis movement flatform of exercise instrument, muscle spindle in subject have been stimulated and these rotation direction and angle caused muscle tonus and contraction that makes muscle, flexibility and based physical fitness improve more. Our study can be used rehabilitation exercise program to aged people and patient with lumbar injury.

• 한국노년학
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• v.29 no.4
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• pp.1261-1275
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• 2009

Age related decrease of muscle strength, balance, and gait abilities bring about physical inactivity in the elderly. Virtual reality (VR) training has been used successfully to rehabilitate functional balance and mobility in elderly subjects. This study was aimed at determining the effect of VR-based exercise programs by using a video game on the muscle strength, balance, and gait abilities in the elderly. 48 old people were randomly divided into two groups; VR-group (men: 11, women: 14, age: 68.42yrs) and control group (men: 10, women: 13, age: 67.58yrs). VR-group performed an exercise program twice a week for 8 weeks and control group had no intervention. The VR-based exercise program was composed of warm up(10 mins), VR-program(40 mins), and cool down(10mins). It was performed by playstation eyetoy play that provided visual and auditory feedback as well as movements of the upper and lower extremities. Muscle strengths of the knee and ankle were measured using manual muscle tester. Static balance was estimated using computerized posturography. Dynamic balance was measured by Timed up and go test (TUG), Functional reach test (FRT). 10m walk test and 6-min walk test were used to assess gait abilities. After the completion of the VR-exercise program, muscle strength, balance, and gait abilities were improved significantly (p<0.05). In conclusion, the VR-based exercise program showed improvement on the muscle strength, balance, and gait ability in the elderly. This exercise program is both effective and interesting for this age group.

• Journal of the Korean Society of Propulsion Engineers
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• v.16 no.5
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• pp.1-9
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• 2012

The gas jet from a coaxial porous injector for two-phase flows is discharged from the porous surface, which encloses the center liquid jet, and the gas and liquid jet interact with each other physically. The wall injected gas jet transfers the radial momentum effectively while the radial gas jet develops to axial jet, and the performance of atomizing and mixing can be improved. In this study, the Weber number and the ratio of momentum flux were controlled by changing the gas injection area and the mass flow rate of the gas jet, and a study on the spray characteristics at the cold-flow test using water and air simulant was performed. It is concluded that the radial momentum transfer concept of a coaxial porous injector gives a positive effect on the atomization and mixing of the two-phase spray.

• Journal of the Korean Chemical Society
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• v.55 no.3
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• pp.454-462
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• 2011

A study on the adsorption characteristics of Pb(II) and Cr(III) cations onto C-methylcalix[4]resorcinarene (CMCR) has been conducted. CMCR was produced by one step synthesis from resorcinol, acetaldehyde, and HCl. Most parameters in batch system confirm that CMCR is a good adsorbent for Pb(II) and Cr(III). Cr(III) uptake was bigger than that of Pb(II), but Cr(III) adsorption rate was slower than Pb(II). The adsorption kinetic of Pb(II) and Cr(III) adsorptions in batch followed pseudo $2^{nd}$ order kinetics model, but the kinetic of Pb(II) adsorption in fixed bed column system followed first order model. Desorption studies to recover the adsorbed Pb(II) was performed sequentially with distilled water and HCl, and the results showed that the adsorption was dominated by chemisorption.