• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.1219-1224
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• 2004

The objective of this study is to propose an experimental calibration facility in which a heat flux sensor can be calibrated under conductive condition by using helium gas. The heat flux calibration facility was designed, simulated and manufactured for use in a high heat transfer condition. It delivers heat fluxes up to a maximum of 35 KW $m^{-2}$. A copper block heated electrically with 3.5 KW power is designed to produce uniform temperature up to 600 K across its face. High heat fluxes are provided between hot plate and cold plate by 1 mm height helium filled gap. A cold plate is maintained around 300 K through pool boiling using a refrigerant and water-cooled heat exchanger. A simulation was conducted to verify the design of the main test section. To verify the performance of calibration facility, a heat flux sensor was examined. The measured heat fluxes were compared to the calculated one.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2012년도 제45회 KOSCO SYMPOSIUM 초록집
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• pp.49-51
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• 2012

In this paper, the integration issue, such as an air-side integration design between the gas turbine and air separation unit, is described and analyzed by the exergy and energy balance of the combined-cycle power block in an IGCC power plant. The results showed that the net power of the system was almost same, but that of the gas turbine was decreased as the integration degree increased. The highest exergy loss was occurred in the combustor of gas turbine, which was affected by the chemical reaction, heat conduction, mass diffusion, and viscous dissipation.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1995년도 가을 학술발표회 논문집
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• pp.329-333
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• 1995

The usual methods for the temperature control of mass-concrete structures include the use of low-heat cement, pre-cooling, or pipe-cooling. In order to control the heat of hydration of mass-concrete structures such as massive pier or anchor block, and mat foundation, the pipe cooling method is widely acceptable for pratical use. In this paper, method of analysis using the Finite Element Method was applied to analyze the heat exchange on the field of three dimensional thermal conduction. The result of analysis Well agreed with experimentally measurement data by "KUMATANI". The method of this analysis will be used widely to control the heat of hydration by the pipe cooling in mass-concrete.-concrete.

• 열처리공학회지
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• 제23권6호
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• pp.323-330
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• 2010

The present study was motivated by increasing demands on quantitative measurements of the heat flux through the water cooling and quenching process of hot steel. The local heat flux measurements are employed by a novel experimental technique that has a function of high-temperature heat flux gauge in which test block assemblies are directly used to measure the heat flux variation during water cooling and quenching of hot steel. The heat flux can be directly achieved by Fourier's law and is also compared with numerical estimation which is solved by inverse heat conduction problem (IHCP). The high-temperature heat flux gauge developed in this study can be applicable to measure cooling rate and history during the actual cooling applications of steelmaking process. In addition, the measurement uncertainty of heat flux is calculated by a quantitative uncertainty analysis which is based on the ANSI/ASME PTC 19.1-2005 standard.

• 대한의용생체공학회:의공학회지
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• 제17권4호
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• pp.507-514
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• 1996

The automated ECG diagnostic systems in hospital have a low P-wave detection capacity in case of some diseases like conduction block. The purpose of this study is to improve the P-wave detection ca- pacity using wavelet transform. The first procedure is to remove baseline drift by subtracting the median filtered signal from the original signal. The second procedure is to cancel ECG's QRS-T complex from median filtered signal to get P-wave candidate. Before we subtracted the templete from QRS-T complex, we estimated the best matching between templete and QRS-T complex to minimize the error. Then, wavelet transform was applied to confirm P-wave. In particular, haiti wavelet was used to magnify P-wave that consisted of low frequency components and to reject high frequency noise of QRS-T complex cancelled signal. Finally, p-wave was discriminated and confirmed by threshold value. By using this method, We can got the around 95.1% P-wave detection. It was compared with contextual information.

• Bulletin of the Korean Chemical Society
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• 제16권10호
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• pp.929-933
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• 1995

The electronic band structure and electrical properties of KMo4O6 containing chains of condensed molybdenum octahedra are analyzed by means of the extended Hu&ckel tight-binding method. KMo4O6 has partially filled bands of 1D as well as 3D character. They also exhibit the anisotropic band dispersions with bandwidths much larger along the c* axis than along the directions perpendicular to it. Thus, conduction electrons are essentially delocalized along the c* direction (i.e., the chain of condensed molybdenum octahedra) in the solid. The 1D band of two partially filled d-block bands leads to Fermi surface nesting with the wave vector q=0.3c*. The CDW instability due to this nesting is expected to cause the phase transition associated with the resistivity anomaly at low temperature. The characteristics of metallic behavior in the crystallographic ab plane are explained on the basis of the unnested 2D Fermi surfaces.

• 대한근전도전기진단의학회지
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• 제20권2호
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• pp.135-138
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• 2018

Peroneal neuropathy scarcely can develop after massive weight reduction. A 21-year-old man complained left foot drop after 28% weight reduction (from 94 kgs to 67.5 kgs). During previous seven months, he played PC games with sitting cross-legged more than seven hours a day. In addition, he started a heavily restricted diet three months ago. Except for those, he had neither any medical history nor trauma to his knee. Electrophysiologic study showed the partial conduction block of left peroneal neuropathy at the fibular head. Four-week well balanced diet and physical therapy improved his foot drop. For the prevention of peroneal neuropathy related to weight reduction, well balanced diet and lifestyle modification are needed.

• 한국산학기술학회논문지
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• 제21권6호
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• pp.440-447
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• 2020

조적구조는 소규모 건축물에서는 내력벽으로 사용되나 일반적으로 비내력벽으로 간주되어 건축물 골조구조의 내부공간을 구분하는 칸막이벽으로 활용되어진다. 또한 조적공사에서 블록이나 벽돌간의 접착제로 모르타르를 사용하는 습식공법은 양생시간이 필요하여 기후조건에 영향을 받으며, 특히 지진과 같은 횡력에 대해 모르타르의 균열로 벽체의 전도붕괴 등이 발생할 수 있어 매우 취약한 구조이다. 본 연구에서는 이러한 조적구조의 약축방향 전단강성을 보완하고 습식공법의 단점을 개선하는 건식 콘크리트블록 공법을 제안하고 그 구조거동을 규명하고자 한다. 이에 본 연구에서는 콘크리트블록의 재료물성을 살펴보고 수평반복하중에 대한 구조거동실험을 통해 제안된 건식조립 콘크리트블록 벽체의 내진성능을 검증하고자 한다. 본 연구결과에 의하면 첫째로, 콘크리트블록은 KS규준에 C종 블록의 재료성능 이상을 확보하고 있어 습식공법을 대신하는 건식공법에 적용할 수 있을 것이다. 둘째로, 수평반복하중에 대한 벽체의 구조성능은 벽체의 수평길이가 길어짐에 따라 사용된 표준형블록의 증가로 다수의 대각선방향 균열대를 형성하면서 조립블록벽체의 내력이 커짐을 알 수 있다. 끝으로 제안된 건식조립 콘크리트블록 벽체구조는 높이와 길이에 의한 벽체의 형상비가 수평 하중을 받는 구조거동에 주요 영향변수로 판단되어 이를 고려한 내진성능평가가 필요하다.

• 대한임상독성학회지
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• 제2권1호
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• pp.7-11
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• 2004

Purpose: We would evaluate the cardiovascular manifestations of the patients with acute organophosphate and carbamate poisoning in the emergency department. Methods: This was retrospectively studied with the review of patient's charts, included total 38 patients were admitted during the past two years in the emergency department of Yeungnam university hospital with the diagnosis of organophosphate or carbamate poisoning. Results: Cardiovascular complications were variously developed in many patients. Electrocardiographic findings were as follows; 4 ($10.5\%$) cardiac arrhythmias included 1 cardiac arrest caused by ventricular fibrillation, 14 ($36.8\%$) sinus tachycardias, 3 ($7.9\%$) sinus bradycardias, and 17 ($44.7\%$) normal sinus rhythms. Conduction disturbances were 23 ($60.5\%$) like as prolonged QTc, 4 ($10.5\%$) ST-T changes, 2 (5.3%) first degree AV block, and 3 ($7.9\%$) right bundle branch block were shown. Other cardiovascular complications were 22 ($57.9\%$) hypertensives, 4 ($10.5\%$) hypotensives, 15 ($39.5\%$) tachycardias, 2 ($5.3\%$) bradycardias, 18 ($47.4\%$) hypoxemics, 12 ($31.6\%$) metabolic acidosis, and 9 ($23.7\%$) pulmonary edemas. Sixteen patients ($42.1\%$) needed ventilatory support because of respiratory paralysis. No patients died in hospital and 36 ($94.7\%$) patients were alive-discharged. Conclusion: Cardiovascular complications are variously in patients with acute organophosphate and carbamate poisoning. Especially, some findings included ventricular arrhythmias, QTc prolongation, hypoxemia, acidosis, and blood pressure changes are known as major precipitating factors to increase the mortality. So, intensive support and aggressive treatment are needed in patients shown various cardiovascular manifestations in the emergency department.

• Journal of Chest Surgery
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• 제33권2호
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• pp.139-145
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• 2000

Background: The purpose of this study is to review the clinical course after the correction of noncomplicated ventricular septal defect and to analyze the morbidity and risk factors of postoperative complications and evaluate residual defect during the follow-up period. Material and Method: From September 1994 to June 1998 24 patients(median age 10 months) underwent surgery under the diagnosis of ventricular septal defect. We made a retrospective review of the clinical records including the operation notes critical care unit records echocardiography results and the follow-up records. Result: There was no early mortality nd late mortality. There was no postoperative complete conduction block. Respiratory complication was the most common complication. The body weight age type of ventricular septal defect associated anomalies and operative procedure were not related to the incidence of complications. residual ventricular septal defects aortic valve regurgitation and tricuspid valve regurgitation were insignificant in postoperative hemodynamics, Conclusions: Correction of the noncomplicated ventricular septal defect was done without mortality and complete heart block. Aggressive preoperative medical treatment and early surgical treatment may decrease postoperative complications. Postoperative residual shunt and tricuspid regurgitation were not problematic during the follow-up