• Journal of Advanced Marine Engineering and Technology
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• v.39 no.7
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• pp.709-715
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• 2015

Underwater gliders do not typically have separate propellers for forward motion. They generate propulsive forces based on the difference between their buoyancy and gravity. They can control the volume from the buoyancy engine to adjust the propulsive force. In addition, the attitude of the underwater glider is controlled by a rubberless motion controller. The motion controller can change the mass center and moment of inertia of the inner moving mass. Owing to the change in these parameters, the attitude of the underwater glider is changed. In this study, we derive nonlinear, six degree of freedom (DOF) mathematical models for the motion controller and buoyancy engine. Using these equations, we perform dynamic simulations of the proposed underwater glider, and verify the suitability of the design and dynamic performances of the proposed underwater glider. We then perform the motion control simulation for the pitch and roll angle, and analyze the dynamic performance according to the pitch and roll angles.

• Korean Journal of Applied Biomechanics
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• v.18 no.1
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• pp.245-253
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• 2008

The purpose of this study was to analyze the effects of shoes with curved out-sole on the posture variation and its control strategy. At first, Target shoes(s) was made by evaluating the static postures of 7-female university students via 'New York State Posture Test' on shoes which made the relative angle between foot surface and ground surface of shoe change. At second, we evaluated muscle activity for 30-female university students(10 persons-3 groups) on shoes which were s(target), m shoes with curved out-sole and n shoes with flat out-sole. 1. The posture scores on New York State Posture Test were statistically different according to the relative angle changes, and the best angle for score was -7 degree but, the scores charts were like two humped camel at -2, -7degree. we made the shoe with -7 degree and curved out-sole. 2. s, m shoes with curved out-sole had graded muscle activities but, static posture on bare foot, there were the graded activity on gastrocnemius for s shoes and tibialis anterior for m shoes, but on shoes, only Gastrocnemius for s shoes.

• Journal of Acupuncture Research
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• v.22 no.1
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• pp.211-221
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• 2005

Objective : The aim of this study is to review clinical trials on the effectiveness of acupuncture in stroke rehabilitation. Methods : Computerized literature searches was carried out on three electronic databases, and hand-searching on some chinese medical journals in library of Kyung Hee Medical Center. Results : 1) Sixteen articles of clinical trials were collected and reviewed. Among these articles, randomized controlled trials were achieved in nine articles. 2) In three articles, statically significant results in improvement of mobile abilities, activities of daily life and Quality of life were reported after acupuncture treatment applied as a part of stroke rehabilitation. In three articles no statically significant changes were reported. 3) Among two articles about spasticity, One about the upper limbs and the results showed statically significant improvement of the spasticity after acupuncture treatment as stroke rehabilitation, and the other was about the lower limbs and the results showed no statically significant changes. 4) One article about acupuncture and postural control showed statically significant results suggesting that acupuncture promotes normalization of postural control after stroke.

• Journal of Periodontal and Implant Science
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• v.29 no.3
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• pp.593-607
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• 1999

치주인대세포는 치주인대의 유지와 개조에 있어서 중요한 역할을 담당하는 섬유아세포성 세포로서, 세포에 가해진 여러가지 조건에 따라 다양한 표현형의 변화를 나타내는 것으로 알려져 있다. 기계적 응력은 치주인대세포의 세포증 식과 밀접히 연관되어 있는 것으로 알려져 있으며, 이는 세포주기 조절인자들의 발현을 증가 시킴으로써 이루어질 것으로 생각되나 그 자세 한 작용기전은 알려져 있지 않다. 그러므로 이 연구의 목적은 기계적 응력이 사람 치주인대세 포의 세포증식과 세포주기 조절인자의 발현에 미치는 영향을 연구하기 위하여 사람 치주인대 세포에 기계적 응력을 가한 후 세포증식을 관찰하고 , 세포주기조절인자들인 p 53 , $p21^{WAF1/CIP1}$ cyclin-dependent kinases(cdks), cyclins 및 proliferating cell nuclear antigen(PCNA)의 단백질 발현 변화를 연구하였다. 본 연구에 사용한 사람 치주인 대세포는 교정치료를 목적으로 발거한 건전한 사람 소구치의 치주인대로부터 explantation culture하여 얻은 후 계대배양을 시행하여 제6 계대의 세포를 사용하였다. 배양한 사람 치주인 대세포를 55-mm Petriperm dish당 $1{\times}10^4$ 개를 분주하고, dish당 1kg의 기계적 응력을 가하면서 12일동안 세포배양을 시행하였다. 사람 치주인대세포의 세포증식은 기계적 응력을 가한 후 8-12일 사이에 현저히 증가하였으며, PCNA 단백질의 발현은 기계적 응력을 가한 후 6-10일 사이에 현저히 증가하였다. 또한 기계적 응력은 사람 치주 대세포의 cdk4, cdk6, cdk2 및 cyclin D1 단백질의 발현을 다소 증가 시켰으나, p53 및 $p21^{WAF1/CIP1}$ 단백질의 발현은 큰 변화가 없었다. 이상의 결과 서 기계적 응력은 사람 치주인대세포 의 p53 및 $p21^{WAF1/CIP1}$ 단백질 발현의 변화 없이 cdks 단백질 발현을 증가시킴으로써 세포증식을 증가시키는 것으로 생각된다.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.4
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• pp.245-254
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• 2018

The purpose of this study is to review the relationship between psychological capital and organizational commitment/ innovative behavior, and the moderating effect of organizational support. In order to verify and achieve the purposes mentioned above, questionnaire data were gathered and analysed from 315 professors and teachers of Korea Politechnics Colleges. Multiple regression and multiple hierarchical regression analysis were applied to test the proposed hypotheses: 1) the relationship between psychological capital and organizational commitment, 2) the relationship between psychological capital and innovative behavior, 3) the moderating effect of organizational support on the relationship between psychological capital and organizational commitment, 4) the moderating effect of organizational support on the relationship between psychological capital and innovative behavior. Empirical survey's findings are as follows; First, self-efficacy and optimism appeared to be positively related with organizational commitment, and all psychological capital factors(self-efficacy, resilience and optimism) appeared to be positively related with innovative behavior. Second, organizational support appeared to have moderating effect partly on the relationship between psychological capital and organizational commitment, but it did not have a moderating effect on the relationship between psychological capital and innovative behavior. Self-efficacy and optimism appeared to be more positively related with organizational commitment in higher organizational support situation than in lower organizational support situation.

• Development and Reproduction
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• v.15 no.4
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• pp.273-279
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• 2011

Epigenetic regulation is a phenomenon that changes the gene function without changing the underlying DNA sequences. Epigenetic status of chromosome is regulated by mechanisms such as histone modification, DNA modification, and RNAi silencing. In this review, we focused on histone methylation for epigenetic regulation in ES cells. Two antagonizing multiprotein complexes regulate methylation of histones to guide expression of genes in ES cells. The Polycomb repressive complex 2 (PRC2), including EED, EZH2, and SUZ12 as core factors, contributes to gene repression by increasing trimethylation of H3K27 (H3K27me3). In contrast, the Trithorax group (TrxG) complex including MLL is related to gene activation by making H3K4me3. PRC2 and TrxG accompany a variety of accessory proteins. Most prominent feature of epigenetic regulation in ES cells is a bivalent state in which H3K27me3 and H3K4me3 appear simultaneously. Concerted regulation of PRC2, TrxG complex, and H3K4- or H3K27-specific demethylases activate expression of pluripotency-related genes and suppress development-related genes in ES cells. Modified balance of the regulators also enables ES cells to efficiently differentiate to a variety of cells upon differentiating signals. More detailed insights on the epigenetic regulators and their action will lead us to better understanding and use of ES cells for future application.

• Journal of Korea Multimedia Society
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• v.17 no.2
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• pp.248-256
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• 2014

This paper designs a serious game for rehabilitation of patients with body pains because they sit down for a long time in the same position, or less physical movement. Activity-based game induces to player improvements in physical exercise with fun elements of the game through entertainment to help the body function and substantially increases the player's commitment during challenging goal. This research is a game design that combines the treatment of color and movement of body to the rhythm of the music. We constructed with XNA Game Studio and KINECT interface with gesture recognition technology. We need to research of evaluation system and test for the actual effect of the treatment and advanced functions of game playes like adding various musics and variety of motion.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.159.2-159.2
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• 2014

간접띠간격(indirect bandgap)을 갖는 층상형 반도체 $MoS_2$는 두께가 줄어들어 단일층이 되면 층간 상호작용의 변화로 인해 ~1.8 eV의 직접띠간격(direct bandgap)을 갖게 된다. 이러한 초박형 $MoS_2$의 발광 특성을 활용하기 위해서는 원자 크기 수준에서 두께와 물성을 조절할 수 있는 화학적 표면개질법에 대한 이해가 필요하다. 최근 아르곤(Ar) 플라즈마를 이용한 $MoS_2$의 층상(layer-by-layer) 식각과 표면제어에 관한 연구결과가 보고되었으나 자세한 반응 메커니즘은 알려져 있지 않다. 본 연구에서는 산소 플라즈마에 의한 단일층 및 복층 $MoS_2$의 산화반응을 원자힘 현미경(AFM), 광전자 분광법(XPS), 라만 및 광발광 분광법을 통해 관찰하고 반응 메커니즘을 이해하고자 한다. 플라즈마로 생성된 산소라디칼과의 반응시간이 증가함에 따라 $E{^1}_{2g}$와 $A_{1g}$-진동모드에서 기인하는 라만 신호, 그리고 A와 B-엑시톤에서 유래하는 광발광의 세기가 감소함을 확인하였다. XPS와 AFM을 통해 반응이 진행됨에 따라 $MoS_2$의 상층이 $MoO_3$로 산화되면서 나노입자로 응집되어 표면형태가 변화하는 것을 확인하였다. 이 결과는 플라즈마 산화반응을 이용하여 $MoS_2$ 표면에 구조적 결함(defect)과 층상 식각을 유발하고 광발광 특성 제어를 위해 전자구조를 조절할 수 있다는 가능성을 보여준다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.252-257
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• 2000

연구 결과를 간단히 요약하면 다음과 같다. 1) 온천 목적으로 개발된 국내 심부 암반 지하수(조사 대상 시료수 419개)는 화강암 및 화강편마암 지역에서 가장 높은 불소 함량을 보이며, 최소 75% 이상의 시료에서 먹는 물 수질 기준을 초과하였다. 2) 화강암 및 화강편마암 지역의 심부 지하수 내 불소 함량은 특히 Na-HCO$_3$ 유형의 지하수에서 높게 나타났는데, 이 유형의 지하수 수질은 사장석, 흑운모를 위시한 규산염 광물의 비조화 용해 반응에 의해 조절된다 이들 지하수는 비교적 깊은 관정심도를 나타내었다. 3) 백악기 화강암과 물과의 용출 반응 실험 결과, 전암 분말과의 반응에서는 최대 7 mg/l의 불소가, 흑운모의 용출 실험에서는 최대 35 mg/1의 불소가 용출되었다. 형석의 포화지수는 비교적 반응 초기에 침전 조건에 근접한 반면, 흑운모의 포화지수는 지속적으로 용해 조건에 놓여 있음을 확인하였다. 따라서, 국내 화강암 지역 심부 지하수 내의 불소는 대부분 흑운모의 비조화 용해 반응에 의해 용출되며, 용출 이후에는 형석의 용해/침전 평형 반응에 의해 그 농도가 조절되는 것으로 확인된다. 4) 앞으로, 보다 자세한 평형 열역학적 해석과 다른 이온종과의 상호 관계 규명 및 광물학적 검토를 통하여 불소의 기원과 거동에 관한 보다 정확한 해석을 시도할 계획이다.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1993.05a
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• pp.70-70
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• 1993

Fundamental frequency is controlled by contraction of both TA and CT muscle. While activity of the CT is known well, little is known regarding the effect of the TA muscle on vocal fold vibration. To study this, a previously developed in vivo canine laryngeal model was modified. Isolated TA muscle activation was obtained by stimulating sectioned terminal TA branches through small thyroid cartilage windows. The results indicated that TA muscle activation is a major determinant in vocal register shift from falsetto to modal phonation. F0 increased with increasing TA activation in modal register, On the other hand, the F0 decreased with TA activation when the evoked voice belonged to falsetto register. Subglottic pressure increased gradually and OQ decreased gradually with TA activation.