• Title/Summary/Keyword: Enhanced

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The Experimental Study on the Heat Transfer of HFC134a for Condensation Tubes with Various Enhanced Surfaces (응축전열관 외부형상 변화에 따른 HFC134a의 열전달 실험)

  • Park Chan-Hyoung;Lee Young-Su;Jeong Jin-Hee;Kang Yong-Tae
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.18 no.8
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    • pp.613-619
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    • 2006
  • The objectives of this paper are to study the characteristics of heat transfer for enhanced tubes (19.05 mm) used in the condenser with high saturation temperatures and to provide a guideline for optimum design of a condenser using HFC134a. Three different enhanced tubes are tested at a high saturation temperature of $59.8^{\circ}C$ (16 bar); a low-fin and three turbo-C tubes.. The refrigerant, HFC134a is condensed on the outside of the tube while the cooling water flows inside the tube. The film Reynolds number varies from 130 to 330. The wall subcooling temperature ranges from $2.7^{\circ}C$ to $9.7^{\circ}C$. This study provides experimental heat transfer coefficients for condensation on the enhanced tubes. It is found that the turbo-C(2) tube provides the highest heat transfer coefficient.

Removal of diesel hydrocarbons by microwave-enhanced soil vapor extraction (Focused on Loss and Kinetic constant for Diesel Hydrocarbons)

  • 김종운;박갑성
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2004.04a
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    • pp.223-226
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    • 2004
  • In this paper, removal of diesel hydrocarbons (C$_{10}$-C$_{22}$) for dry and moist soil was investigated so that microwave-enhanced soil vapor extraction(SVE) reduced soil treatment time and raised remediation efficiency. Kinetic constants of diesel hydrocarbons with microwave energy were 7 times on dry soil and 1580 times on moist soil as much as those of SVE process without microwave energy. The diesel removals were 67.7~78.4% for $C_{10}$ and $C_{12}$, and 0~18.5% for $C_{14}$~C$_{22}$ for dry and moist soil with SVE process only. On the other hand, dry soil with microwave-enhanced SVE process showed 89.3~99.4% removal for $C_{10}$ and $C_{12}$ and 35.6~67.0% for hydrocarbons over $C_{14}$. All hydrocarbons(C$_{10}$~C$_{22}$) studied were significantly removed (93.6~99.8%) for moist soil with microwave-enhanced SVE process. Almost all diesel hydrocarbons were usually considered as semi-volatile compounds(SVOCs). Microwave-enhanced SVE process might have a great potential for remediation of soils contaminated with SVOCs.OCs.

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Enhanced remote-sensing scale for wind damage assessment

  • Luo, Jianjun;Liang, Daan;Kafali, Cagdas;Li, Ruilong;Brown, Tanya M.
    • Wind and Structures
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    • v.19 no.3
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    • pp.321-337
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    • 2014
  • This study has developed an Enhanced Remote-Sensing (ERS) scale to improve the accuracy and efficiency of using remote-sensing images of residential building to predict their damage conditions. The new scale, by incorporating multiple damage states observable on remote-sensing imagery, substantially reduces measurement errors and increases the amount of information retained. A ground damage survey was conducted six days after the Joplin EF 5 tornado in 2011. A total of 1,400 one- and two-family residences (FR12) were selected and their damage states were evaluated based on Degree of Damage (DOD) in the Enhanced Fujita (EF) scale. A subsequent remote-sensing survey was performed to rate damages with the ERS scale using high-resolution aerial imagery. Results from Ordinary Least Square regression indicate that ERS-derived damage states could reliably predict the ground level damage with 94% of variance in DOD explained by ERS. The superior performance is mainly because ERS extracts more information. The regression model developed can be used for future rapid assessment of tornado damages. In addition, this study provides strong empirical evidence for the effectiveness of the ERS scale and remote-sensing technology for assessment of damages from tornadoes and other wind events.

Immunoenhancing Effect of 1,2-Benzopyrone on the Oxidative Burst Activity to Phagocytic Response of Canine Peripheral Blood Phagocytes (개 말초혈액 탐식세포의 탐식반응에 따른 순간산소 과소비현상에 있어 1,2-benzopyrone의 면역증강효과)

  • 김현아;강지훈;양만표
    • Journal of Veterinary Clinics
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    • v.21 no.3
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    • pp.236-242
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    • 2004
  • 1,2-benzopyrone can stimulate macrophages to increase the ability of phagocytosis. Peripheral blood polymorphonuclear cells (PMN) and macrophages destroy microbial organisms with reactive oxygen species (ROS), called oxidative burst activity (OBA). This study was undertaken to determine whether 1,2-benzopyrone affects the OBA on the phagocytic response of canine peripheral blood phagocytes. The OBA of phagocytes in the addition or absence of latex beads was analyzed by flow cytometry system using dihydrorhodamine 123 (DHR). The direct treatments of 1,2-benzopyrone have no effect on the OBA of peripheral blood mononuclear cells (PBMC), PMN and monocyte-rich cells regardless of addition of latex beads. When latex beads are added to PMN, the OBA of PMN was remarkably enhanced by culture supernatant from PBMC but not PMN treated with 1,2-benzopyrone. Similary, it was also enhanced by human recombinant (hr) $TNF-\alpha.$ However, when latex beads were not added to PMN, its OBA was not enhanced by culture supernatant from either PBMC or PMN treated with 1,2-benzopyrone. The OBA of latex beads-phagocytized PBMC and monocyte-rich cells was not enhanced by culture supernatant from either PBMC or PMN treated with 1,2-benzopyrone. These results strongly suggested that 1,2-benzopyrone has an immunoenhancing effect on the OBA of PMN when phagocytic response occurred only. This enhanced OBA may be mediated through active humoral substance(s), such as $TNF-\alpha,$ produced by PBMC stimulated with 1,2-benzopyrone.

Enhanced Recovery after Cancer Surgery using Dokhwaljihwang-tang-gami : A Case Series (독활지황탕가미를 이용한 암 수술 후 조기 회복 : 연속 증례 보고)

  • Jung, Nu-ri;Choi, Yu-jin;Kim, Ki-tae;Shin, Seon-mi;Ko, Heung
    • The Journal of Internal Korean Medicine
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    • v.41 no.2
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    • pp.248-255
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    • 2020
  • Objectives: Fatigue, malnutrition, and weight loss are common complaints after undergoing surgery for cancer. These symptoms can be associated with Yin-Deficiency (陰虛) of Exhaustion syndrome (虛勞). Therefore, this study aimed to determine if it is possible to use Dokhwaljihwang-tang, which originates from Yukmijihwang-tang, for enhanced recovery after cancer surgery. Methods: After cancer surgery, Dokhwaljihwang-tang-gami was administered three times a day, in 80-120 ml doses at a time. Results: In four cases of gastric, colorectal, and thyroid cancer, enhanced recovery was achieved using Dokhwaljihwang-tang-gami to treat general weakness, fatigue, and pain in the surgical site after cancer surgery. Conclusions: Dokhwaljihwang-tang can be used for enhanced recovery after cancer surgery.

A Fully Integrated CMOS Security-Enhanced Passive RFID Tag

  • Choi, Suna;Kim, Hyunseok;Lee, Sangyeon;Lee, Kangbok;Lee, Heyungsub
    • ETRI Journal
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    • v.36 no.1
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    • pp.141-150
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    • 2014
  • A fully integrated CMOS security-enhanced passive (SEP) tag that compensates the security weakness of ISO/IEC 18000-6C is presented in this paper. For this purpose, we propose a security-enhanced protocol that provides mutual authentication between tag and reader. We show that the proposed protocol meets the security demands of the ongoing international standard for RFID secure systems, ISO/IEC 29167-6. This paper fabricates the SEP tag with a 0.18-${\mu}m$ CMOS technology and suggests the optimal operating frequency of the CMOS SEP tag to comply with ISO/IEC 18000-6C. Furthermore, we measure the SEP tag under a wireless environment. The measured results show that communications between the SEP tag and reader are successfully executed in both conventional passive and SEP modes, which follow ISO/IEC 18000-6C and the proposed security enhanced protocol, respectively. In particular, this paper shows that the SEP tag satisfies the timing link requirement specified in ISO/IEC 18000-6C.

Pool Boiling Heat Transfer Coefficients of R1234yf on Various Enhanced Surfaces (열전달 촉진 표면에서 R1234yf의 풀 비등 열전달계수)

  • Lee, Yohan;Kang, Dong Gyu;Seo, Hoon;Jung, Dongsoo
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.25 no.3
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    • pp.143-149
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    • 2013
  • In this work, nucleate pool boiling heat transfer coefficients (HTCs) of R134a and R1234yf are measured, on flat plain, 26 fpi low fin, Turbo-B, Turbo-C and Thermoexcel-E surfaces. All data are taken at the liquid pool temperature of $7^{\circ}C$, on a small square copper plate ($9.53mm{\times}9.53mm$), at heat fluxes from $10kW/m^2$ to $200kW/m^2$, with an interval of $10kW/m^2$. Test results show that nucleate boiling HTCs of all enhanced surfaces are greatly improved, as compared to that of a plain surface. Nucleate pool boiling HTCs of R1234yf are very similar to those of R134a, for the five surfaces tested.

A Study on the Effect of Pre-treatment on the Formation of Nitriding Layer by Post Plasma (포스트 플라즈마를 이용한 질화의 질화층 형성에 미치는 전처리의 영향에 대한 연구)

  • Moon, Kyoung Il;Byun, Sang Mo;Cho, Yong Ki;Kim, Sang Gweon;Kim, Sung Wan
    • Journal of the Korean Society for Heat Treatment
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    • v.18 no.1
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    • pp.24-28
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    • 2005
  • New post plasma nitriding can achieve a high uniformity that have been difficult in DC nitriding and have a high productivity comparable to gas nitriding. However, it has not a enough high nitriding potential for a rapid nitriding, because surface activation or ion etching in the general plasma nitriding cannot be expected. Thus, in this study, the effects of pre-treatments with oxidation and reduction gas have been investigated to improve the nitriding kinetics of post plasma nitriding. An effective pre-treatment consisting of oxidation and reduction resulted in the increase of surface energy of STD 11. This induced the surface hardness and the effective nitriding depth of STD 11. It is thought that the increase of the surface energy and the surface area with pre-treatment promote the nucleation of nitriding layer.

DIAGNOSTIC ABILITY OF THE PERIAPICAL RADIOGRAPHS AND DIGITAL IMAGE IN THE DETECTION OF THE ARTIFICIAL PROXIMAL CARIES (인공적 인접면 치아우식증의 구내방사선사진과 디지털 영상의 진단능 평가)

  • Heo Min-Suk;You Dong-Soo
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.24 no.2
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    • pp.439-450
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    • 1994
  • Recently, the digital image was introduced into radiological image. The digital image has the power of contrast enhancement, histogram control, and other digitally enhancement. At the point of the resolution, periapical radiograph is superior to the digital image, but enhanced digital procedure improves the diagnostic ability of the digital image. The purpose of this study was to evaluate the diagnostic ability of artificial proximal caries in conventional radiographs, digital radiographs and enhanced digital radiographs (histogram specification). ROC (Receiver Operating Characteristic) analysis and paired t-test were used for the evaluation of detectability, and following results were acquired: 1. The mean ROC area of conventional radiographs was 0.9274. 2. The mean ROC area of unenhanced digital image was 0.9168. 3. The mean ROC area of enhanced digital image was 0.9339. 4. The diagnostic ability of three imaging methods was not significant difference(p>0.05). So, the digital images had similar diagnostic ability of artificial proximal caries to conventional radiographs. If properly enhanced digital image, it may be superior to conventional radiographs.

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Safety Regulation of Enhanced In-Service Inspection(ISI) in Nuclear Power Plant (원자력발전소 강화 가동중검사 안전규제)

  • Shin, Ho-Sang
    • Journal of the Korean Society for Nondestructive Testing
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    • v.30 no.4
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    • pp.380-385
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    • 2010
  • The integrity of components and piping of operating nuclear power plants has been identified by in-service inspection(ISI) requirements and activities commensurate with standards and codes such as KEPIC MI or ASME Code Section XI. However, the other various degradation mechanisms not considered during design stage of nuclear power plants have been checked by enhanced ISI. The requirements of enhanced ISI have been voluntarily developed by the industry itself or strickly issued by regulatory body. Even though the requirements were developed by the industry, they should be reviewed by regulatory body for their application in nuclear power plants. The enhanced ISI activities and requirements of non-destructive examination(NDE) which reflect the degradation issues in nuclear power industry will be primarily discussed in this paper.