• International Journal of Highway Engineering
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• v.11 no.3
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• pp.151-161
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• 2009

This study was conducted to investigate the characteristics of the curling behavior of long-span pavement slabs under environmental loads. By developing and using finite element models of the long-span pavement slabs, the stress distribution and the effects of slab length, slab thickness, stiffness of underlying layers, and the restraints of the slab ends on the curling behavior were analyzed. In addition, the field experiments were performed with the actual long-span pavement slab to obtain the curling behavior of the real structure under environmental loads. As a result of this study, it was found that the vertical displacements of the long-span pavement slab along the centerline due to the curling behavior were zero except for the areas near the slab ends, and the curling stresses were maximum and constant where the displacements were zero. The slab length and the stiffness of underlying layers did not affect the maximum curling stresses. The restraints at the slab ends made the curling stresses occur near the slab ends, but did not much affect the maximum curling stresses.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.177-177
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• 2011

Complementary metal-insulator-metal capacitor에서 $SiO_2$는 절연체로 널리 사용되고 있었으나, 반도체 소자의 고직접화로 인한 선폭의 감소로 터널링 효과에 의해 누설전류가 증가하여, 대체 물질에 대한 연구가 활발히 진행되고 있다. 그 중 $ZrO_2$는 고유전율, wide bandgap, 열안정성의 특징을 가지고 있어 대체 물질로 주목 받고 있다. $ZrO_2$ 박막 제작에는 sputter, atomic layer deposition 등의 진공증착을 이용한 방법과 용액을 이용한 sol-gel 법이 있다. 화학용액을 이용한 sol-gel 법은 소자의 패턴을 프린트 할 수 있는 장점과 상대적으로 값싼 공정으로 인해 최근 주목 받고 있지만, 진공증착법에 비해서 연구가 전무한 실정이다. 본 연구에서는 sol-gel 법에 의해 프린트된 $ZrO_2$ 박막의 광특성을 분광타원편광분석법으로 연구하였다. Si 기판위에 0.1 M의 $ZrO_2$ sol을 입힌 뒤에 $300{\sim}700^{\circ}C$의 온도에서 열처리 하였다. 분광타원 편광분석기로 1.12~6.52 eV 에너지 영역에서 측정하였고, $ZrO_2$ 박막의 광특성 분석을 위해서 Tauc-Lorentz 모델을 이용하였다. 그 결과 고온에서의 열처리로 인해 효율이 높아서 소자로 이용할 수 있는 tetragonal 구조를 가진 $ZrO_2$ 박막이 형성됨을 분석할 수 있었다. 본 연구는 sol-gel법으로 제작된 $ZrO_2$ 박막의 고직접, 고속 소자응용성과 비파괴적인 광특성 분석법을 제시하고 있다.

• Journal of Applied Biological Chemistry
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• v.43 no.2
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• pp.104-108
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• 2000

The plant growth-promoting activity of Acremonium strictum MJN1 isolated from roots of Panox ginseng was explored. The myceliaI extract of A. strictum MJN1 enhanced the rice seedling growth by 14.5 and 9.0% in the dried weight of shoots and roots, and the growth of red pepper by 54 and 85% in the top length and the dried weight in pot experiments, respectively. The plant growth-promoting substances in the myceliaI extract of Acremonium strictum MJN1 were identified as D-adenosine and glycerol. Both commercial D-adenosine and glycerol also promoted significantly the rice seedling growth but, unlike the mycelial extract of A. strictum MJN1, hardly affected the yields of plants grown in pots or field. Therefore, it is possible that other plant growth-promoting substances are produced by A. strictum MJN1. However, this study shows that A. strictum MJN1 has a great potential as a biofertilizer.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.15 no.2
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• pp.19-30
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• 2019

In this study, to evaluate conservatism of various fatigue life evaluation procedures, fatigue tests were conducted using compact tension (CT) specimens with a round notch, made of A516 Gr.70 carbon steel and A240 TP304 stainless steel, under load-controlled cyclic condition. Experimental fatigue failure cycles were measured and compared with predicted fatigue lives using two different life evaluation methods; (1) Design-By-Analysis (DBA) procedure given in ASME B&PV Code, Sec. III, Div. 1, Subsec. NB-3200 and (2) structural stress-based approach provided in ASME B&PV Code, Sec. VIII, Div. 2, Part 5. To predict fatigue failure cycles, three-dimensional elastic finite element analysis was conducted. Fatigue lives were predicted by both design fatigue curve given in ASME B&PV Code, Sec. III, Div. 1, Appendices and best-fit fatigue curve suggested in NUREG/CR-6815 for the DBA procedure. Finally, fatigue lives evaluated by various methods were compared with test results, and then conservatism between each evaluation procedure was discussed.

• Perspectives in Nursing Science
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• v.15 no.2
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• pp.81-91
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• 2018

Purpose: This study aimed to suggest strategies for advancing local-government-based accreditation systems and surveyor training in long-term care facilities in Korea. Methods: A comprehensive review of the literature including research papers and official reports issued by governments from the United States, Australia, and Japan was conducted to explore domestic and international policies related to long-term care facility certification and accreditation systems. Results: The USA has two types of care quality assurance systems including mandatory certification (5-star rating system) by the Centers for Medicare and Medicaid Services and voluntary accreditation by the Joint Commission on Accreditation of Healthcare Organizations. Australia operates a government-based mandatory accreditation system for all long-term care facilities through the Australian Aged Care Quality Agency. Japan, particularly the Tokyo district, operates a third-party evaluation system that involves the voluntary participation of long-term care facilities. Conclusion: This study provides several strategies to enhance accreditation processes and surveyors'expertise. For instance, motivating facilities to voluntarily participate in accreditation is necessary by 1) providing sufficient and continuous consultations and feedback about how to improve care quality, 2) differentiating accreditation domains and indicators from the national health insurance certification system, and 3) actively utilizing accreditation results and providing incentives.

• Korean Journal of Optics and Photonics
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• v.16 no.6
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• pp.521-526
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• 2005

We assembled the optical beam director with diameter 300 mm. This consists of primary, secondary mirrors and 5 folding mirrors. Among them, the primary mirror is the most important component so that we measure any possible deformation on it at every step of assembly. Also, we developed the systematic alignment algorithm, which is essential because the number of mirrors is 7. The final wavefront error of the system is 1.9 wave rms (wave=633 nm) which is 7 times larger than we expected. The main source is the deformation of the 131ding mirrors. We expect that what we have learned from the assembly of this system would be helpful when we deal with a larger system in the future.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.6
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• pp.567-577
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• 2017

Obesity is known to induce inhibition of glucose uptake, reduction of lipid metabolism, and progressive loss of skeletal muscle function, which are all associated with mitochondrial dysfunction in skeletal muscle. Mitochondria are dynamic organelles that regulate cellular metabolism and bioenergetics, including ATP production via oxidative phosphorylation. Due to these critical roles of mitochondria, mitochondrial dysfunction results in various diseases such as obesity and type 2 diabetes. Obesity is associated with impairment of mitochondrial function (e.g., decrease in $O_2$ respiration and increase in oxidative stress) in skeletal muscle. The balance between mitochondrial fusion and fission is critical to maintain mitochondrial homeostasis in skeletal muscle. Obesity impairs mitochondrial dynamics, leading to an unbalance between fusion and fission by favorably shifting fission or reducing fusion proteins. Mitophagy is the catabolic process of damaged or unnecessary mitochondria. Obesity reduces mitochondrial biogenesis in skeletal muscle and increases accumulation of dysfunctional cellular organelles, suggesting that mitophagy does not work properly in obesity. Mitochondrial dysfunction and oxidative stress are reported to trigger apoptosis, and mitochondrial apoptosis is induced by obesity in skeletal muscle. It is well known that exercise is the most effective intervention to protect against obesity. Although the cellular and molecular mechanisms by which exercise protects against obesity-induced mitochondrial dysfunction in skeletal muscle are not clearly elucidated, exercise training attenuates mitochondrial dysfunction, allows mitochondria to maintain the balance between mitochondrial dynamics and mitophagy, and reduces apoptotic signaling in obese skeletal muscle.

• Advances in Traditional Medicine
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• v.10 no.3
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• pp.214-221
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• 2010

Clematis chinensis is the root of Clematis chinensis OSBECK and is classified in Ranunculaceae. Clematis chinensis is a traditional medicinal herb possesses analgesic, diuretic, anti-tumorigenic, and anti-inflammatory effects. In this study, the effect of aqueous extract of Clematis chinensis against lipopolysaccharide-induced inflammation was investigated in mouse BV2 microglial cells. The aqueous extract of Clematis chinensis at the respective concentration was treated one hour before the lipopolysaccharide treatment in mouse BV2 microglial cells. From the present results, pre-treatment with the aqueous extract of Clematis chinensis suppressed prostaglandin E2 synthesis and nitric oxide production by inhibiting on the lipopolysaccharide-stimulated cyclooxygenase-2 and inducible nitric oxide synthase expressions in mouse BV2 microglial cells. The present study suggests that Clematis chinensis may offer a valuable mean of therapy for brain inflammatory diseases.

• Research in Community and Public Health Nursing
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• v.16 no.4
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• pp.446-457
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• 2005

Purpose: The purpose of this study was to analyse researches on nursing intervention for elderly health promotion. Method: A literature review of 38 researches was carried out using guidelines developed by the present researchers. Result: The research papers studied in this research were theses written for doctoral or master's degree and published between 1994 to 2004. These researches applied nursing intervention for health promotion of elders and used experimental study design. The average period of nursing intervention was about 9 weeks and the average frequency was three times per week. As for major characteristics of subject groups, most of them were over 65 years old (76.3%) and resided in community (65.8%), and each group consisted of 10 to 29 elders. The dependent variables used in these studies included physiological variables (blood pressure, blood cholesterol level, pulmonary function, fasting blood sugar, blood cortisol level, body mass etc.), psychologic variables (depression, quality of life, life satisfaction, loneliness, anxiety etc.), cognitive variables (perceived benefits, perceived barriers, self-efficacy, self-concept, subjective health status etc.), activities of daily livings, health promotion behavior, pain, risks of fall, and variables related to Trans Theoretical Model. The majority of these studies (78.9%) applied exercise programs for health promotion including exercise motivating programs (15.8%). Conclusion: We suggest that more various nursing interventions must be applied to promote elders' health and to take care of their chronic diseases.

• Animal cells and systems
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• v.14 no.4
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• pp.237-244
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• 2010

Stress urinary incontinence (SUI) is a common condition that primarily affects women. Here, we investigate the effects of human adipose-derived stem cells (ADSCs) in a rodent model of SUI. Female Sprague-Dawley rats at 7 weeks of age were randomly divided into three groups (n=8 per group): sham-operation, SUI-induction by transabdominal urethrolysis, and SUI-induction followed by transplantation of human ADSCs into the urethra. The abdominal leak point pressure at 8 weeks after the operation was markedly decreased by transabdominal urethrolysis, confirming successful induction of SUI. Interestingly, transplantation of human ADSCs into the urethra significantly blunted the decrease of abdominal leak point pressure in SUI-induced rats. Accordingly, we observed expression of ${\alpha}$-smooth muscle actin in a significant proportion of transplanted ADSCs, indicating differentiation of ADSCs into smooth muscle cells in the urethra. Moreover, the SUI-induced elevations of c-Fos immunoreactivities in the pontine micturition center (PMC) and in the ventrolateral periaqueductal gray (vlPAG) were clearly suppressed by transplantation of human ADSCs. These results imply that human ADSCs can be an effective therapeutic modality to ameliorate the symptoms of SUI.