• 제목/요약/키워드: Mild

검색결과 5,479건 처리시간 0.032초

수정완경사방정식의 타원형 수치모형 (Elliptic Numerical Wave Model Solving Modified Mild Slope Equation)

  • 윤종태
    • 한국해양공학회지
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    • 제18권4호
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    • pp.40-45
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    • 2004
  • An efficient numerical model of the modified mild slope equation, based on the robust iterative method is presented. The model developed is verified against other numerical experimental results, related to wave reflection from an arc-shaped bar and wave transformation over a circular shoal. The results show that the modified mild slope equation model is capable of producing accurate results for wave propagation in a region where water depth varies substantially, while the conventional mild slope equation model yeilds large errors, as the mild slope assumption is violated.

경증 및 아임상 우울증의 중의학 임상연구 동향 분석 - China National Knowledge Infrastructure를 중심으로 - (The Analysis of Clinical Trial Research Trend on Mild and Sub-clinical Depression in Traditional Chinese Medicine - using China National Knowledge Infrastructure Database -)

  • 고유미;이시우;김상혁
    • 대한예방한의학회지
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    • 제19권1호
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    • pp.47-59
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    • 2015
  • Objective : The purpose of this study was to analyze the trend of clinical research on 'mild and sub-clinical depressions' in China. Method : The journal search was performed using China National Knowledge Infrastructure(CNKI). Our inclusion criteria were as follows: TCM clinical trials for mild, sub-clinical, early stage of depression. Exclusion criteria were the following: non-TCM clinical trials, disease-associated depression related clinical trials. Results : We included 16 papers in this study. 1. In this study, we realized there have been several mild and sub-clinical depressions related clinical trials conducted in the field of TCM. 2. The result of 10 Journals used the Hamilton Depression Rating Scale for diagnosis and assessment criteria of mild and sub-clinical depressions. 3. The selected journals categorized by various interventions, such as, herbal medicine(7), acupuncture(4), miscellaneous(5). 4. Also, 7 Journals showed the significant improvements in patients with mild and sub-clinical depressions by TCM interventions, and 5 studies of TCM patent prescription reported that herbal medicine therapy has less side effect than the western medicine. Conclusion : Through this study, we found out that several researchers in China performed clinical trials on mild and sub-clinical depressions constantly. From the result of this study, we need to concern about the necessity of research on the mild and sub-clinical depression in Korea. Therefore, this result could be used as a meaningful reference for the design of future clinical trials.

연료유량 변화에 따른 원추형 MILD 연소로의 수치적 해석 (Numerical study of a conical MILD combustor with varing the fuel flow rate)

  • 김태권
    • 한국산학기술학회논문지
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    • 제15권6호
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    • pp.3370-3375
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    • 2014
  • MILD(Moderate and Intense Low Oxygen Dilution) 연소는 열효율 향상과 유해배출가스 저감의 상반된 관계를 해결하기 위한 하나의 각광받는 기술이다. 연소가스의 재순환을 이용하여 고온 연소시에 질소산화물을 낮게 유지함과 동시에 연소로 내부온도를 균일화함으로써 열효율을 향상시킬 수 있는 기술이다. 본 연구는 실험실 규모의 노에서 원추형 MILD 연소기의 연소특성을 나타내고 있다. 연구의 조건은 공기의 유량은 일정하게 하면서 가스 연료 유량을 변화시켜 당량비를 변화시켰다. 이 결과 노 내에서 MILD 연소영역이 잘 구현되었고, 당량비 0.69~0.83의 범위에 걸쳐서 노(爐)내에서의 온도와 배출가스의 농도가 각각 예측되었다. 이 당량비 구간에서 최고화염온도 영역과 주 반응영역에서의 온도차가 약 $300^{\circ}C$의 안정적인 화염 영역의 존재를 확인하였다.

MILD 연소로에서 Coanda 노즐 효과를 이용한 배기가스 재순환에 관한 연구 (A Study on the Exhaust Gas Recirculation in a MILD Combustion Furnace by Using the Coanda Nozzle Effect)

  • 하지수;심성훈
    • 대한환경공학회지
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    • 제35권12호
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    • pp.967-972
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    • 2013
  • 질소산화물 저감에 큰 효과가 있는 MILD 연소는 고온의 배기가스가 연소로내에 유입되는 양에 따라 질소산화물 저감 특성이 많은 영향을 받는다. 본 연구에서는 동심원관 형태의 MILD 연소로에서 바깥 원통의 배기가스 통로에서부터 안쪽 원통의 연소통로 사이에 연결관을 설치하고 배기가스를 유입하기 위해 coanda 노즐을 사용하였다. 이러한 coanda 노즐의 기하학적 형상 변화에 따라 고압공기 유량, 배기가스 유입량 특성을 수치해석을 통해 살펴봄으로써 최적의 coanda 노즐 형상을 도출하는 것을 본 연구의 목적으로 하였다. 본 연구의 전산 해석의 결과는 conada 노즐의 노즐 통로 간격이 0.5 mm, 노즐 각도 $4^{\circ}$, 노즐 확관 길이 146 mm일 때 최적의 유입량비가 되었고 노즐 통로 수직 길이는 유입량비에 무관하였다.

의치상 직접 이장재의 표면 특성에 관한 비교 연구 (A COMPARATIVE STUDY OF SURFACE CHARACTERISTICS OF DIRECT RELINE RESINS)

  • 안종관;이준규;정재헌
    • 대한치과보철학회지
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    • 제39권1호
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    • pp.49-57
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    • 2001
  • The use of autopolymerizing-cured resin and light-cured resin for direct introral relining of complete and partial dentures has been popular. The purpose of this investigation was to determine the surface characteristics of autopolymerizing-cured reline resins(Tokuso rebase, Mild rebaron, Meta base) and light-cured reline resin(Mild rebaron LC). Acrylic resin slab specimens(1.0cm in diameter at the bottom, and 0.3cm high) were made against glass according to the instructions of the manufacturer following normal procedures for each of direct reline resins and examined the surface characteristics by use of surface profilometer and the other specimens which were made intraorally for each of direct reline resins were examined by use of scanning electron microscopy. The results were as follows : 1. Each surface roughness(Rz) of hard relin resins was $0.14{\pm}0.04{\mu}m$ in Tokuso rebase, $0.37{\pm}0.11{\mu}m$ in Mild Rebaron, $0.79{\pm}0.44{\mu}m$ in Mild Rebaron LC, $6.36{\pm}3.40{\mu}m$ in Meta base. There were significant differences between the surface roughness of Meta base and those of other reline resins(p<0.05) 2. The generation of porosity was the most in Tokuso Rebase and followed by Meta base, Mild Rebaron and Mild Rebaron LC in the order respectively. 3. Light-cured reline resin(Mild rebaron LC) was denser in surface than any other autopolymerizing-cured reline resins. Tokuso rebase and Mild rebaron was denser than Meta base. Conclusively, light-cured reline resin(Mild rebaron LC) had less porosity and better surface density than any other autopolymerizing-cured reline resins.

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의치상 직접 이장레진의 색조 안정성 (THE COLOR STABILITY OF DIRECT DENTURE RELINE RESINS)

  • 강은숙;전영찬;정창모
    • 대한치과보철학회지
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    • 제41권2호
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    • pp.160-168
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    • 2003
  • Statement of problem : Direct denture reline resins tend to discolor during service in the oral environment by intrinsic and extrinsic factor. Purpose : This study was designed to evaluate the color stability of direct denture reline resins. Material and methods : Mild Rebaron(GC Corp., Japan), Meta Base M(Sun medical Co., Japan), Mild Rebaron LC(GC Corp., Japan) and as a control group, Vertex SC(Dentimex Zeist, Holland) were chosen for this study. Ten specimens of each direct denture reline resins were fabricated. Treatment methods designed for this study were the coffee staining test(7days) and the accelerated aging test(100hours). The color changes before and after treatment were measured by Tristimulous colorimeter(Yasuda seiki seisakusho, Ltd. Japan) and analyzed. Results All the direct denture reline resins subjected to the coffee staining test and the accelerated aging test showed noticible difference in color change. After coffee staining test, Meta Base M showed the highest color change followed by Vertex SC. Mild Rebaron LC and Mild Rebaron. There were no statistical differences between Meta Base M and Vertex SC and between Mild Rebaron LC and Mild Rebaron(p>0.05). After accelerated aging test. Mild Rebaron LC showed the highest color change followed by Vertex SC, Meta Base M and Mild Rebaron. There were no statistical differences only between Mild Rebaron and Mata Base M(p>0.05) but among the others, there were statistical differences(p<0.05). Conclusion : Within the limitation of this study, all the direct denture reline resins subjected to the extrinsic and intrinsic factors showed noticible difference in color change, and there were differences among manufacturers.

Incidence of Post-Traumatic Stress Disorder after a Mild Traumatic Brain Injury : Preliminary Investigation Using the Brief Neuropsychological Screening Test

  • Choi, Mi Sun;Seo, Sook Jin;Oh, Chang Hyun;Kim, Se-Hyuk;Cho, Jin Mo
    • Journal of Korean Neurosurgical Society
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    • 제55권4호
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    • pp.190-194
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    • 2014
  • Objective : Post-traumatic stress disorder (PTSD) is a group of diseases that are observed in patients who had experienced a serious trauma or accident. However, some experienced it even after only a mild traumatic brain injury (TBI), and they are easily ignored due to the relatively favorable course of mild TBI. Herein, the authors investigated the incidence of PTSD in mild TBI using brief neuropsychological screening test (PTSD checklist, PCL). Methods : This study was conducted on patients with mild TBI (Glasgow coma scale ${\geq}13$) who were admitted from January 2012 to December 2012. As for PCL, it was done on patients who showed no difficulties in communication upon admission and agreed to participate in this study. By using sum of PCL, the patients were divided into high-risk group and low-risk group. PTSD was diagnosed as the three major symptoms of PTSD according to the Diagnostic and Statistical Manual of Mental Disorders, fourth-edifion. Results : A total of 314 TBI patients were admitted and 71 of them met the criteria and were included in this study. The mean age was 52.9 years-old (range : 15--94). The mean PCL score was 28.8 (range : 17--68), and 10 patients were classified as high-risk group. During follow-up, 2 patients (2.7%) of high risk group, were confirmed as PTSD and there was no patient who was suspected of PTSD in the low-risk group (p=0.017). Conclusion : PTSD is observed 2.8% in mild TBI. Although PTSD after mild TBI is rare, PCL could be considered as a useful tool for screening of PTSD after mild TBI.

Pilot급 산소 MILD 연소에 관한 실험 및 수치해석적 연구 (An Experimental and Numerical Study on the Oxy-MILD Combustion at Pilot Scale Heating Capacity)

  • 차천륜;이호연;황상순
    • 설비공학논문집
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    • 제28권7호
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    • pp.275-282
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    • 2016
  • MILD (Moderate and Intense Low-oxygen Dilution) combustion using oxygen as an oxidizer is considered as one of the most promising combustion technologies for high energy efficiency and for reducing nitrogen oxide and carbon dioxide emissions. In order to investigate the effects of nozzle angle and oxygen velocity conditions on the formation of oxygen-MILD combustion, numerical and experimental approaches were performed in this study. The numerical results showed that the recirculation ratio ($K_V$), which is an important parameter for performing MILD combustion, was increased in the main reaction zone when the nozzle angle was changed from 0 degrees to 15 degrees. Also, it was observed that a low and uniform temperature distribution was achieved at an oxygen velocity of 400 m/s. The perfectly invisible oxy-MILD flame was observed experimentally under the condition of a nozzle angle of $10^{\circ}$ and an oxygen velocity of 400 m/s. Moreover, the NOx emission limit was satisfied with NOx regulation of less than 80 ppm.

The Effect of Temperature on the Corrosion of Mild Steel in H3PO4 Containing Halides and Sulfate Ions

  • Chandrasekaran, V.;Kannan, K.;Natesan, M.
    • Corrosion Science and Technology
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    • 제4권1호
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    • pp.8-14
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    • 2005
  • The corrosion behaviour of mild steel in phosphoric acid solution in the presence and absence of pollutants viz. Chloride, Fluoride and Sulfate ions at 302K-333K was studied using mass loss and potentiostatic polarization methods. The addition of chloride and sulfate ions inhibits the mild steel corrosion in phosphoric acid while fluoride ions stimulate it. The effect of temperature on the corrosion behaviour of mild steel indicated that inhibition of chloride and sulfate ions decreased with increasing temperature. The adsorption of these ions (Chloride and sulfate) on the mild steel surface in acid has been found to obey Langmuir adsorption isotherm. The values of activation energy (Ea) and free energy of adsorption ($\Delta$) indicated physical adsorption of these ions (chloride and sulfate) on the mild steel surface. The plot of $logW_{f}$ against time (days) at 302K gives a straight line, which suggested that it obeys first order kinetics and also calculate the rate constant k and half-life time $t_{1/2}$.

A Study on Optimal Operation Strategy for Mild Hybrid Electric Vehicle Based on Hybrid Energy Storage System

  • Bae, SunHo;Park, Jung-Wook
    • Journal of Electrical Engineering and Technology
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    • 제13권2호
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    • pp.631-636
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    • 2018
  • This paper proposed an optimal operation strategy for a hybrid energy storage system (HESS) with a lithium-ion battery and lead-acid battery for mild hybrid electric vehicles (mild HEVs). The proposed mild HEV system is targeted to mount the electric motor and the battery to a conventional internal combustion engine vehicle. Because the proposed mild HEV includes the motor and energy storage device of small capacity, the system focuses on low system cost and small size. To overcome these limitations, it is necessary to use a lead acid battery which is used for a vehicle. Thus, it is possible to use more energy using HESS with a lithium battery and a lead storage battery. The HESS, which combines the lithium-ion battery and the secondary battery in parallel, can achieve better performance by using the two types of energy storage systems with different characteristics. However, the system requires an operation strategy because accurate and selective control of the batteries for each situation is necessary. In this paper, an optimal operation strategy is proposed considering characteristics of each energy storage system, state-of-charge (SOC), bidirectional converters, the desired output power, and driving conditions in the mild HEV system. The performance of the proposed system is evaluated through several case studies with respect to energy capacity, SOC, battery characteristic, and system efficiency.