• Title/Summary/Keyword: 열성형

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An Experimental Study on the Thermal Performance of Air Filled Thermal Diode (공기를 작동 유체로 하는 열다이오드의 열성능에 관한 실험적 연구)

  • Pak, Ee-Tong;Jang, Young-Geun;Hwang, In-Ju
    • Solar Energy
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    • v.17 no.2
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    • pp.35-42
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    • 1997
  • Thermal diode is a device which allows heat to be transferred in one direction by convection due to difference of density of fluid, and blocks heat flow in the opposite direction. Vertical plate for heat collection and radiation are of utility for design of thermal diode. It was considered the transient and steady state of air filled thermal diode with guide vane which combined rectangular and parallelogrammic shape enclosures. $Gr^*$ was kept constantly on $1.11{\times}10^{10}{\sim}1.4{\times}10^{10}$ and error range was ${\pm}3%$ during the experiment. Nu was examined when inclined angle are $15^{\cir\c}\;and\;45^{\circ}$ and, also the experiments was carried out with and without guide vane as well. Specially, Nu was linearly increased due to increase of $Gr^*$, and the effect of guide vane and dimensionless channel depth was sensitive. Developed state of temperature began at dimensionless time $0.5{\sim}0.6$ due to variation of inclined angle, which is characteristic of system.

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A case of Niemann-Pick disease type A (A형 Niemann-Pick 병 1례)

  • Yu, Ho Yen;Oh, Ji Eun;Park, Jae Sun;Kim, Mi Hyang;Kim, Sin Dong;Jung, Kyung Soon
    • Clinical and Experimental Pediatrics
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    • v.49 no.12
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    • pp.1358-1362
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    • 2006
  • Niemann-Pick disease is a group of autosomal recessive disorders associated with hepatosplenomegaly, variable neurologic deficits, and the storage of sphingomyelin and other lipids. Seven cases have been reported in Korea. We report an additional case presenting with hypotonia, early neurodevelopmental delay, hepatosplenomegaly and death by persistent pneumonia and asphyxia at the age of 23 months. MRI of brain and fundoscopic findings of our case at 4 months of age were normal. However, abnormal intensity of the thalamus and atrophy of the right temporal lobe on the MRI and macular cherry red spots were noticed at the age of 17 months. A bone marrow biopsy showed large foamy cells, while hexosaminidase A and B levels were normal. Although biochemical or molecular workup was not done, these findings led to the diagnosis of infantile onset Niemann-Pick disease, probably type A. A brief review of the related literatures was made.

Inheritance of Chlorosis under Low Temperature Condition in Rice (벼 유묘기 저온처리에 의한 Chlorosis의 유전)

  • Kim, Kyung-Min;Kwon, Yong-Sham;Sohn, Jae-Keun
    • Current Research on Agriculture and Life Sciences
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    • v.15
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    • pp.1-5
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    • 1997
  • The purpose of this study was to determine the inheritance of chlorosis under low temperature at seedling stage of rice. The expression of chlorosis among 21 rice cultivars treated at $18^{\circ}C$ showed in one Tongil type cultivar, Milyang 23, and two Indica type cultivars, IR 36 and Dular. The sign of chlorosis was not appeared in all of the japonica type cultivars under the same treatment. The reduction of chlorophyll content under the low temperature was differed from varietal group and cultivars. The $F_2$ population from a cross between Toyohatamochi and Dular segregated 3:1 ratio for normal and white phenotypes of third leaf. From the result, it was suggested that the chlorosis was controlled by a single recessive gene. The chlorosis rice detected from this study will be used as a good material for the genetic study related to photosynthetic ability of rice.

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Fabrication of complete denture using Centric tray and closed mouth technique for edentulous patient (과도한 치조제 흡수를 보이는 무치악 환자에서 Centric tray와 폐구법 인상을 이용한 총의치 수복 증례)

  • Jung, Sua;Ma, Boyoung;Yang, Hongso;Park, Sangwon;Lim, Hyun-Pil;Yun, Kwidug
    • The Journal of Korean Academy of Prosthodontics
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    • v.56 no.2
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    • pp.120-125
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    • 2018
  • Conventional denture impression techniques have limitations for edentulous patients with severe alveolar bone resorption and can cause problems from excessive border extension. Especially when a patient has movable tissue it is difficult to make accurate impression, thus might interrupt stable seating of complete denture. Fabrication of complete denture using closed mouth technique for edentulous patient with severe ridge resorption is thought to provide better stability and retention. In this case, an 86-year-old patient had both edentulous jaws with epulis fissuratum on maxillary anterior ridge and severe mandibular ridge resorption. Thus, tentative vertical dimension was determined by using Centric trayand individual tray attached with gothic arch tracer was fabricated. Complete denture was fabricated using closed mouth technique and the patient was satisfied with better stability and retention of the complete denture.

A Study on the Performance Comparisons of Air Type BIPVT Collector Applied on Roofs and Facades (건물 적용 유형별 공기식 BIPVT 유닛의 전기 및 열성능 비교에 관한 연구)

  • Kang, Jun-Gu;Kim, Jin-Hee;Kim, Jun-Tae
    • Journal of the Korean Solar Energy Society
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    • v.30 no.5
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    • pp.56-62
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    • 2010
  • The integration of PV modules into building facades or roof could raise their temperature that results in the reduction of PV system's electrical power generation. Hot air can be extracted from the space between PV modules and building envelope, and used for heating in buildings. PV/thermal collectors, or more generally known as PVT collectors, are devices that operate simultaneously to convert solar energy from the sun into two other useful energies, namely, electricity and heat. This paper compares the experimental performance of BIPVT((Building-Integrated Photovoltaic Thermal) collectors that applied on building roof and facade. There are four different cases: a roof-integrated PVT type and a facade-integrated PVT type, the base models with an air gap between the PV module and the surface, and the improved models for each types with aluminum fins attached to the PV modules. The accumulated thermal energy of the roof-integrated type was 15.8% higher than the facade-integrated regardless of fin attachment. The accumulated electrical energy of the roof-integrated type was 7.6% higher, compared to that of the facade-integrated. The efficiency differences among the collectors may be due to the fact that the pins absorbed heat from the PV module and emitted it to air layer.

Preparation and Self-Confidence to Response to Emergent, Acute or Life-threatening Health Crisis among School Nurses in South Korea (학교내 응급상황에 대한 준비 실태와 보건교사의 응급처치 수행자신감)

  • Kim, Ji-yeon;Jeong, Ihn Sook
    • The Journal of Korean Society for School & Community Health Education
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    • v.21 no.3
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    • pp.21-34
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    • 2020
  • 배경 및 목적: 본 연구는 학교 내 응급상황(천식 위기, 알레르기 반응, 저혈당 위기, 발작, 심폐정지, 출혈/골절, 머리/목 상해, 열성질환, 중독, 질식)에 대한 행정 차원과 물품구비 차원에서의 준비 실태, 그리고 응급처치 수행자신감을 파악하는데 목적이 있다. 방법: 단면조사연구로 274명의 보건교사를 대상으로 하였으며, 자가보고형 조사지를 이용하여 대상자와 학교의 일반적 특성, 학교 내 응급상황에 대한 행정·물품 준비 실태, 그리고, 응급처치 수행자신감 등 3개 영역의 자료를 수집하였다. 자료수집은 2018년 2월 1일부터 2018년 7월 31일까지 실시하였고, 자료분석은 기술통계, t-검정과 분산분석을 이용하였다. 결과: 대부분의 학교에서 응급상황 관리계획이 있었으나, 응급상황별로 천식 위기는 46.7%, 알레르기 반응은 58.4%에서만 관리계획을 갖추고 있었다. 산소, 혈당측정기, 자동제세동기, 경추고정장치 등은 85% 이상의 학교에서 보유하고 있었으나, 기관확장제 흡입기, 에피네프린 주사제, 흡인기 등은 거의 갖추고 있지 않았다. 응급상황 수행자신감은 5점 만점에 2.67점 (발작관리) 에서 3.55점 (심폐정지관리)이었으며, 일부 응급상황에 대해서 의료기관 근무경력이 증가함에 따라 수행자신감이 증가하였다. 결론: 대부분의 학교에서 응급관리계획을 수립하고 있었으나, 응급상황별 관리계획을 수립한 경우는 반 정도에 불과하였다. 보건교사의 학교 내 응급상황에 대한 응급처치 수행자신감은 전체적으로 낮게 나타남에 따라, 이들의 역량강화를 위한 체계적인 교육과 멘토링 프로그램이 요구된다.

COUPLED ANALYSIS OF INJECTION MOLDING AND FILM FORMING FOR IDENTIFYING FILM DEFORMATION IN IMD PROCESS (IMD 공정 중 필름 변형 특성 파악을 위한 사출 및 필름성형 간 연계해석)

  • Yoon, J.H.;Hur, N.;Bae, A.H.;Lee, T.H.
    • Journal of computational fluids engineering
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    • v.18 no.3
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    • pp.20-25
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    • 2013
  • In various manufacturing industries, an in-mold decoration (IMD) process for plastic objects is widely utilized because a film forming and an injection molding processes run simultaneously. In the present study, the deformation of polymer film and filling of resin in the IMD process were numerically investigated to evaluate the quality of the plastic object formed by the IMD process, which consists of thermoforming and injection molding processes. To obtain the initial shape of the polymer film during the injection molding process, the deformation of the polymer film in the thermoforming process was pre-formed using the vacuum conditions to attach the film to a cavity. Since the properties and deformation of polymer film are greatly affected by the behavior of polymer resin being injected into a mold cavity, numerical simulations for the injection molding and film forming were performed with one-way coupling method. The results showed that the injected resin could lead to the tearing of the polymer film in local regions near the corners. In order to verify the proposed numerical methodology, the numerical results of the deformation patterns printed on the initial polymer film were compared with the experimental data. The proposed methodology to couple film forming analysis with injection molding analysis can be used to predict the deformation of film in IMD process.

COMPARISON OF CRANIAL BASE MORPHOLOGY BETWEEN THE MANDIBULAR PROGNATHISM AND MAXILLARY RETROGNATHISM IN SKELETAL CLASS III PATIENTS (하악과성장형과 상악열성장형 골격성 Ⅲ급 부정교합군간의 두개저 형태 비교)

  • Kang, Dong-Hwa;Kwon, Tae-Geon;Lee, Sang-Han;Kim, Hyun-Soo
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.33 no.3
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    • pp.204-210
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    • 2007
  • This study was intended to compare the cranial base morphology between the mandibular prognathism and maxillary retrognathism in skeletal class III patients. The subject of the present study was composed of 88 patients divided into two groups; Group 1 (Skeletal Class III with mandibular prognathism. SNA within normal range, SNB over normal range, n=54) and Group 2(Skeletal Class III with maxillary retrognathism. SNA below normal range, SNB within normal range, n=34). Lateral cephalogram were taken immediate before surgery and 18 landmarks were used to analyze the characteristics of cranial base and maxillomandibular skeleton. The result revealed that cranial base angle is significantly smaller in Group 1 than Group 2, which implies the influence of the cranial base angulation on the mandibular position. However the posterior cranial base length did not influence the mandibular horizontal position and anterior cranial base length did not influence the maxillary horizontal position. As the anterior cranial base length was closely related with ramal height, it is recommendable to investigate the regulatory mechanism of chondrogenesis of cranial base and condyle cartilage in the future research.

A Fatal Case of Neonatal Onset Carbamoyl Phosphate Synthetase I Deficiency with Homozygous CPS1 Mutation (동종 접합자 CPS1 돌연 변이를 동반한 신생아 발병형 Carbamoyl Phosphate Synthetase 1 결핍증의 치명적 사례)

  • Yun, Jung Ha;Shin, Seung Han;Ko, Jung Min;Kim, Ee-Kyung;Kim, Han-Suk
    • Journal of The Korean Society of Inherited Metabolic disease
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    • v.18 no.1
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    • pp.18-22
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    • 2018
  • Carbamoyl phosphate synthetase I (CPS1) deficiency is a rare autosomal recessive urea cycle disorder that causes hyperammonemic crisis. CPS1 is the first enzyme encoded by the CPS1 gene, which catalyzes the first step of the urea cycle. In CPS1 deficiency, ammonia, the toxic metabolite produced by the interruption of the urea cycle, is accumulated in the blood and brain, leading to hyperammonemic encephalopathy and irreversible brain damage. Here, we report a fatal case of neonatal-onset CPS1 deficiency in a 4-day-old girl presenting with recurrent seizures, who was revealed to be homozygous for c.1529delG ($p.Gly510Alafs^*5$).

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Effect of Working Fluids on the Thermal Behavior of a Bi-directional Solar Thermal Diode (작동유체가 양방향성 태양열 열다이오드의 열성능 변화에 미치는 영향 분석)

  • Ko, Yung-Joo;Lee, Heon-Ju;Chun, Won-Gee;Chen, Kuan;Lim, Sang-Hoon
    • Journal of the Korean Solar Energy Society
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    • v.28 no.1
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    • pp.9-17
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    • 2008
  • An experimental investigation has been carried out to study the effects of different working fluids on the behavior and thermal performance of a hi-directional thermodiode. The thermodiode was made up of two rectangular loops mounted between a collector plate and a radiator plate. Rotatable joints between the horizontal and inclined segments of the loops enable easy alteration of the direction of heat transfer. The loops and the tank were filled with a working fluid for effective heat transfer when the thermodiode was forwarded biased. Six different working fluids were tested with thermal conductivity values ranging from 0.1 to $0.56W/m-^{\circ}C$, thermal expansion coefficient values ranging from $1.8\;{\times}10^{-4}$ to $1.3\;{\times}\;10^{-3}\;K^{-1}$, and kinematic viscosity values ranging from $0.65\;{\times}\;10^{-6}$ to $100\;{\times}\;10^{-6}\;m^2/s$. Especially, mixtures of $Al_2O_3$ (30nm Particle) in deionized water have been tested for the volumetric ratios of 0.01, 0.02, 0.03, 0.1, 0.2%. Each experiment was carried out after the loop was filled with a working fluid for effective heat transfer and the thermodiode was forwarded biased. The solar thermodiode was heated by a radiant heater consisting of 20 halogen lamps that generated a heat flux of about $1000\;W/m^2$ on the collector surface. Results are given in terms of temperature development in different parts of the loop as heat is delivered from its hot end to the surrounding atmosphere by the radiator made of copper plates.