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        검색결과 440

        221.
        2012.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In the present study, an Element-Based Lagrangian Formulation for the nonlinear analysis of shell structures is presented. The strains, stresses and constitutive equations based on the natural co-ordinate have been used throughout the Element-Based Lagrangian Formulation of the present shell element which offers an advantage of easy implementation compared with the traditional Lagrangian Formulation. The Element-Based Lagrangian Formulation of a 9-node resultantstress shell element is presented for the anisotropic composite material. The element is free of both membrane and shear locking behavior by using the assumed natural strain method such that the element performs very well in thin shell problems. The arc-length control method is used to trace complex equilibrium paths in thin shell applications. Numerical examples for laminated composite curved shells presented herein clearly show the validity of the present approach and the accuracy of the developed shell element.
        4,000원
        222.
        2012.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this article, we proposed a novel technique to fabricate cell‐culturing scaffold, that is, the hollowcylinder‐ grain assembly technique. This technique uses hollow cylindrical particles with sub‐mm thickness. Firstly, we fabricate PCL (polycaprolactone) hollow cylinder with sub-mm thickness using lab-made stainless steel mold. After that, we put the above-mentioned fabricated particles into a metal mold of which temperature could be controlled with hot plate and heat insulation system. PCL particles in the metal mold could be assembled together without severe collapsing under adequate temperature and time. Consequently, we could fabricate scaffold or foam structure with interconnected‐porosity and observed surface of cross section of fabricated scaffold by SEM.
        4,000원
        223.
        2012.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The purpose of this study was to identify the factors determining the participation restriction of chronic stroke patients based on international classification of functioning, disability, and health (ICF) model. Sixty-eight stroke patients participated. The participants were assessed participation restriction using the Korean version of London handicap scale (K-LHS), modified Barthel index (K-MBI) to measure activities of daily living, Berg balance scale (K-BBS) to assess balance, and the center for epidemiologic studies depression (K-CES-D) to gauge depression. Also, 3 minutes walking test (3MWT), gait velocity, asymmetric posture, and family support were assessed. A stepwise multiple regression analysis was used to explore the factors determining participation restriction. There were no significant different in the K-LHS and K-MBI results by gender (p>.05). Correlations between the K-LHS and K-MBI (r=-.656), K-BBS (r=-.543), K-CES-D (r=.266), 3MWT (r=-.363), gait velocity (r=.348), and family support (r=-.389) were significant (p<.05). Also, the K-MBI and family support were the factors that determined participation restriction (p<.05) and that 40.2% of the variation in the K-LHS can be explained. Therefore, it is suggested that evaluation and intervention of patient's activity level and extent of family support is necessary to reduce participation restriction of chronic stroke patients.
        4,000원
        224.
        2012.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study used an unstable platform to change the support surface type and position of both lower limbs in order to determine changes in weight distribution and muscle including the vastus medialis, tibialis anterior, lateral hamstring, and lateral gastrocnemius of both lower limbs were evaluated during knee joint flexing and extending in a semi-squat movement in 32 hemiplegic patients. The support surface conditions applied to the lower limbs were divided into four categories: condition 1 had a stable platform for both lower limbs; condition 2 had an unstable platform for the non-hemiplegic side and a stable platform for the hemiplegic side; condition 3 had a stable platform for the non-hemiplegic side and an unstable platform for the hemiplegic side; and condition 4 had an unstable platform for both sides. The normalized EMG activity levels of muscles and weight bearing ratio of both sides in the four surface conditions were compared using repeated measures ANOVA. A significant increase was found in the weight support distribution for the hemiplegic side in flexing and extending sessions in condition 2 compared to the other conditions (p<.05). A statistically significant decrease in significant decrease in asymmetrical weight bearing in flexing and extending sessions was observed for condition 2 compared to the other conditions (p<.05). A similar significant decrease was found in differences in muscular activity for both lower limbs in condition 2 (p<.05). The muscular activity of the hemiplegic side, based on the support surface for each muscle showed a significantly greater increase in condition 2 (p<.05). An unstable platform for the non-hemiplegic side and a stable platform for the hemiplegic side therefore increased symmetry in terms of the weight support distribution rate and muscle activity of lower limbs in hemiplegic patients. The problem of postural control due to asymmetry in hemiplegic patients should be further studied with the aim of developing continuous effects of functional training based on the type and position of the support surfaces and functional improvement.
        4,000원
        225.
        2011.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The numerous Korean church today embraces the technical goal of the invention building the paradigm of the new mission about the Chinese student studying abroads flowed in into the righteousness, to pay attention to the interior of a country China student studying abroads to the oversea missionary work resource voluntarily, the interior of a country. While the mission environment of Korean Chinese student studying abroads is unable to be good, the result which can be obtained through the missionary activity of the missionaries in China field church is very low. If for the missionary judgment of the Korean churches, the focus is adjusted to the Chinese student studying abroads, the long-term mission strategy which creates the social support system and so that the it has been growing in the mutually different cultural area Chinese student studying abroads can adapt well the Chinese student studying abroads to the Korean culture and college life and can minimize the culture shock because of the gospel will be established. The stress removal factor in which the student studying abroads can take the emotional psychological relaxation is grasped and the Christian culture and the faith settlement, that is the gospel, should be made. the various pattern of adjustments show as to Chinese student studying abroads’ right-foot shoot. However, that it is attached when it has to pay attention. Whether it is familiar with the various factorses including the member of the cultural area, living this success popular culture, language, and etc. or not. However, while the existing values according to the socialist identity which they have in the process of doing Korean college life and world view underwent a lot of difficulties in strange Korean cultural adaptation, the stress was experienced. In this condition, when the church community sets the mission direction and strategy, the many-sided effort for the stress relaxation according to the cultural adaptation of the Chinese student studying abroads is required. the strategic access about how approaching from the position in which the Social Support for canceling the stress required for the cultural adaptation for Korean Chinese college life is needed is required. It has the values, of the church the world view and existing paradigm so far, it is not easy to propagate the Chinese student studying abroads. The strategic access to the new paradigm which can be managed with the form of ‘the come mission’ in ‘it visits mission’ paradigm which the church and missionary group had been providing is desperately required. Therefore the mission resource in which many churches can distinguish the various obstacle according toes the Chinese student studying abroad mission and which can overcome this has to be communally created.
        7,800원
        228.
        2011.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The purpose of this study is to examine the activity ratios of global trunk muscles and local trunk muscles in relation to adjustments in the level of task difficulty while performing stability exercises in easily applied bridging lumbar stabilization exercise. Twenty healthy subjects performed bridging lumbar stabilization exercise while the level of task difficulty was plate was used in the same posture for all the exercises. EMG was used to examine the activity ratios of the global muscles and multifidus in relation to the level of task difficulty. Moreover, the activity ratios of the multifidus muscle, the erector spinae and the gluteus maximus muscle were measured. A one-way ANOVA with repeated measures was used, and a Bonferroni correction was conducted (=.05). When the bridging lumbar stabilization exercise were performed at different difficulty levels, the activity of the multifidus muscle, which is a local muscle, was high in all three exercises. Also, compared to low intensity and intermediate intensity exercises, high intensity exercises showed more significant differences (=.05). Among all the muscles, the multifidus showed the highest activity at intermediate intensity. Based on these results, we suggest that in the case of bridging lumbar stabilization exercise, low intensity or intermediate intensity exercises are more suitable and efficient for local muscle stabilization.
        4,000원
        229.
        2011.08 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Pt nanoparticle catalysts incorporated on RuO2 nanowire support were successfully synthesized and their electrochemical properties, such as methanol electro-oxidation and electrochemically active surface (EAS) area, were demonstrated for direct methanol fuel cells (DMFCs). After fabricating RuO2 nanowire support via an electrospinning method, two different types of incorporated Pt nanoparticle electrocatalysts were prepared using a precipitation method via the reaction with NaBH4 as a reducing agent. One electrocatalyst was 20 wt% Pt/RuO2, and the other was 40 wt% Pt/RuO2. The structural and electrochemical properties of the Pt nanoparticle electrocatalysts incorporated on electrospun RuO2 nanowire support were investigated using a bright field transmission electron microscopy (bright field TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and cyclic voltammetry. The bright field TEM, XRD, and XPS results indicate that Pt nanoparticle electrocatalysts with sizes of approximately 2-4 nm were well incorporated on the electrospun RuO2 nanowire support with a diameter of approximately 50 nm. The cyclic voltammetry results showed that the Pt nanoparticle catalysts incorporated on the electrospun RuO2 nanowire support give superior catalytic activity in the methanol electro-oxidation and a higher electrochemically active surface (EAS) area when compared with the electrospun Pt nanowire electrocatalysts without the RuO2 nanowire support. Therefore, the Pt nanoparticle catalysts incorporated on the electrospun RuO2 nanowire support could be a promising electrode for direct methanol fuel cells (DMFCs).
        4,000원
        230.
        2011.05 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The purpose of this study was to investigate the effects of a task-oriented approach on weight-bearing distribution and muscular activities of the paretic leg during sit-to-stand movement in 18 chronic stroke patients. Both groups were received neurodevelopmental treatment for 30 min/day and then the experimental group (=9) followed additional a task-oriented approach (sit-to stand training with controlled environment) and the control group (=9) followed a passive range of motion exercise for 15 min/day, five days/week, for four weeks. Weight-bearing distribution and muscular activities of the paretic leg during sit-to-stand movement were measured before and after four weeks of training. There was significantly improved weight-bearing distribution of the paretic leg during sit-to-stand movement in the experimental group compared with that of the control group after four weeks of training (p<.05). But electromyographic activities of the quadriceps and the tibialis anterior of the paretic leg were not significantly different (p>.05). Thus, it is necessary to apply a task-oriented approach to improve the weight-bearing distribution of the paretic leg during sit-to-stand movement in chronic stroke patients.
        4,000원
        231.
        2011.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        최근 자연공원 내 케이블카 설치에 대한 타당성 여부를 놓고 찬반 그룹 간에 논쟁이 뜨겁다. 본 연구는 인구사회학적 특성 및 방문경험과 자연과의 유대와의 관계, 자연과의 유대와 케이블카 설치로 인한 결과(사회, 경제, 생태적)에 대한 신념 및 케이블카 설치 지지도와의 관계를 조사하였다. 자료수집은 2010년도 9월 중 총 134명의 무등산도립공원 방문객을 대상으로 현지설문조사를 통해 이루어졌다. 자연과의 유대는 Mayer and Frantz(2004)의 "자연과의 유대척도"를 수정한 척도를 이용하여 측정하였다. 자연과의 유대는 요인분석 결과 2개의 요인, 즉 '상호의존적', '독립적' 요인으로 구분되었다. 응답자의 연령, 교육수준, 무등산도립공원 방문횟수 및 무등산 중봉지역 방문횟수가 높아지거나 많아질수록 자연과의 유대가 증가하였다. 자연과의 유대가 높은 응답자가 낮은 응답자에 비하여 케이블카 설치로 인한 부정적 결과에 대한 신념이 컸지만 긍정적 결과에 대한 신념과는 관계가 없었다. 자연과의 유대 수준이 높은 응답자는 낮은 응답자에 비하여 케이블카 설치에 대한 지지도가 낮게 나타났다.
        4,300원
        233.
        2010.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The transesterification of rapeseed oil, soybean oil, and mixed fat were conducted at 65℃ with Al2O3-supported CaO, 0.8 wt% KOH, 1 wt% NaOH and mixed catalyst. The overall conversion(%) of rapeseed oil indicated to be 96% at the 12:1 molar ratio of methanol to oil, 8 wt% CaO and 2 wt% water. The pH ranges of biodiesel for mixed fat using four catalysts and for three fats using 8wt% CaO were 7.3-9.1, 7.3-7.5, respectively. The volumes of water needed to wash biodiesel from rapeseed oil using 0.8 wt% KOH and 8 wt% CaO were 15 mL and 3 mL.
        4,000원
        234.
        2010.12 구독 인증기관 무료, 개인회원 유료
        본 연구는 스트레스 취약성모델에 근거하여 노인의 스트레스가 자살생각에 미치는 영향의 경로를 검증하기 위해 실행되었다. 독립변수로 노인의 스트레스를, 종속변수로 노인의 자살생각을, 매개변수로 노인의 우울을, 조절변수로 사회적 지지 및 스트레스 대처방안을 설정하고 충청북도에 거주하는 60세 이상 노인 465명을 대상으로 설문조사를 실시하여 자료를 수집하고 구조방정식모형을 이용하여 분석하였다. 연구결과를 요약하면 다음과 같다. 첫째, 인구사회학적 특성에 따른 스트레스, 우울, 자살생각의 수준차이에 유의미한 결과를 나타내었으며, 둘째, 노인의 스트레스가 높을수록 자살가능성 요인이 높아지는 결과를 나타내었다. 셋째, 우울을 매개로 스트레스가 자살생각에 영향을 주는 것으로 나타났으며, 넷째, 스트레스 대처방안이 노인의 스트레스가 노인의 자살생각에 미치는 영향을 조절하는 것으로 나타났다.
        6,000원
        236.
        2010.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        다공성 Poly(propylene) 분리막의 지지 하에 전해질 용액 (EC/DEC 1 : 1 혼합물 내의 LiPF6 1 M 용액) 내에서 DEGDMA [Di(ethylene glycol) dimethacrylate]의 70℃ 열중합을 통하여 겔 고분자 전해질(GPE)막이 합성 되었다. 합성된 겔 고분자 전해질막의 이온전도도 및 전기화학적 안정성은 AC 임피던스법 및 CV (cyclic voltametry)법에 의하여 측정 평가하였다. 겔 고분자를 전해질로, 그리고 양극 및 음극으로는 각각 LiMi0.8Co0.2O2 및 graphite로 이용하여 리튬이온전지(LIB)도 제작하였다. 열중합을 통하여 리튬 이온전지에 적합한 이온전도도(10 -3 S/cm 이상) 및 전기화학적 안정성을 보이면서 자체적인 성상을 유지하는 겔 고분자 전해질막을 얻을 수 있었다. 단량체 함량 5%의 전구체로 제작한 겔 고분자 전지는 단량체 함량이 7.0% 및 10.0%인 경우에 비하여 우수한 고율 및 충-방전 효율을 보였다.
        4,000원
        237.
        2010.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구의 목적은 각기 다른 특성을 갖는 지지체에 따른 정삼투막의 성능을 비교 빛 평가하는 것이다. 계변 중합을 통하여 소수성 지지체인 폴리술폰(PSf)과 상대적으로 친수성 지지체인 폴리에테르술폰(PES)의 표변에 폴리아미드 활성층을 갖는 정삼투막을 제조하여 투과유량과 역확산을 비교하였다. PSf 정삼투막과 PES 정삼투막의 투과유량은 4.36 L/m2hr와 17.8 L/m2hr으로 PES를 지지체로 하는 정삼투막이 투과성능이 더 우수함을 알 수 있었으며, 이를 통해 지지체의 친수성과 정삼투 공정에서의 투과성능 간에 관련성이 존재함을 확인할 수 있었다. 또한 막의 두께가 앓아질수록 정삼투 공정에서 막의 투과유량은 증가하였다.
        4,000원
        238.
        2010.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        IS (요오드-황)프로세스의 HI 분해반응 공정에서의 적용을 목적으로 지르코니아 코팅 지지체를 이용하여 CVD법에 의해 수소분리막을 제작하였으며, 분리막으로서의 가능성을 평가하였다. 제작한 막의 형상 및 Si의 분포를 파악하기 위해 SEM 및 EPMA를 이용하여 분석하였다. 지르코니아를 코팅한 지지체를 이용하여 제작한 막에 Zr-Si-O층이 존재한다는 것을 알 수 있었다. 제작한 막의 수소와 질소가스의 단일 성분 투과속도를 300~600℃에서 측정하였다. 600℃에서 Z-1막에서의 수소투과속도는 1 × 10 -7 mol·Pa -1·m -2·s -1를 나타냈다. 질소에 대한 수소의 선택성은 Z-1 막에서 5.0, Z-2막에서 5.75를 나타냈다.
        4,000원
        239.
        2010.08 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        As a starting material, BCP (biphasic calcium phosphate) nano powder was synthesized by a hydrothermal microwave-assisted process. A highly porous BCP scaffold was fabricated by the sponge replica method using 60 ppi (pore per inch) of polyurethane sponge. The BCP scaffold had interconnected pores ranging from 100 μm to 1000 μm, which were similar to natural cancellous bone. To realize the antibacterial property, a microwave-assisted nano Ag spot coating process was used. The morphology and distribution of nano Ag particles were different depending on the coating conditions, such as concentration of the AgNO3 solution, microwave irradiation times, etc. With an increased microwave irradiation time, the amount of coated nano Ag particles increased. The surface of the BCP scaffold was totally covered with nano Ag particles homogeneously at 20 seconds of microwave irradiation time when 0.6 g of AgNO3 was used. With an increased amount of AgNO3 and irradiation time, the size of the coated particles increased. Antibacterial activities of the solution extracted from the Ag-coated BCP scaffold were examined against gram-negative (Escherichia coli) and gram-positive bacteria (Staphylococcus aureus). When 0.6 g of AgNO3 was used for coating the Ag-coated scaffold, it showed higher antibacterial activities than that of the Ag-coated scaffold using 0.8 g of AgNO3.
        4,000원
        240.
        2010.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구에서는 연료전지용 강화 복합막 지지체 제조를 위해 높은 다공성을 가지는 PVdF 평막을 제조하였다. 높은 다공도로 인한 낮은 기계적 강도를 보완하기 위한 방법으로 나노 사이즈의 laponite를 막 내에 분산시켰다. 제조된 PVdF/Laponite 복합막의 모폴로지 및 다공도는 SEM 분석 및 무게 중량법을 사용하여 평가하였고, 60% 이상의 다공도를 보였다. 첨가된 laponite 함량에 따른 막의 열적 안정성은 105℃, 135℃에서의 수축률을 이용하여 평가하였으며, laponite 함량이 5%일 때 135℃에서 MD와 TD방향으로의 열 수축률 2~3%와 2~3.5%를 나타내었다. Laponite 첨가 후 막의 기계적 강도가 향상되었으며, 순수 PVdF 막에 비해 약 30%의 모듈러스 증가를 나타내었다.
        4,000원