• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.330-333
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• 2008

The hybrid air-conditioner, where air is cooled both by convection and radiation, is developed. The indoor unit of the air-conditioner consists of radiation panel and dehumidification coil, where refrigeration R-134a is supplied by independent refrigeration cycles. Optimum refrigerant charge was 750g for both cycles. Optimum evaporation pressure was 3.7 bar for the radiation panel cycle and 3.9 bar for the dehumidification cycle. The cooling capacity of the radiation panel was 1.01 kW and that of the dehumidification coil was 0.94kW, which yielded COP of 3.3.

• Proceedings of the Korea Information Processing Society Conference
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• 2021.05a
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• pp.66-69
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• 2021

최근 실시간 응답 및 처리에 민감한 서비스들이 급증하면서 멀티액세스 엣지 컴퓨팅(MEC)이 차세대 기술로 주목받고 있다. 사용자들의 잦은 이동성 때문에 MEC 서버들 사이에서의 마이그레이션은 중요한 문제로 다뤄진다. 본 논문에서는 이동성이 많은 차량 엣지 컴퓨팅 환경을 고려하였으며, 강화학습 기법인 Q-learning 을 사용하여 마이그레이션 여부 및 대상을 결정하는 기법을 제안하였다. 제안 기법의 목적은 지연 제약조건을 만족시키면서 차량 엣지 컴퓨팅 서버(VECS) 사이의 로드 밸런싱을 최적화하는 것이다. 제안 기법의 성능 비교를 통하여 다른 기법들보다 로드 밸런싱 측면에서 약 22-30%, 지연 제약조건 만족도 측면에서 약 20-31%로 더 좋은 성능을 보임을 확인하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2021.05a
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• pp.70-73
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• 2021

Mobile Edge Computing(MEC)는 사용자 근처에서 서비스를 제공하기 때문에 사물인터넷에서 주목받고 있는 기술이다. 오프로딩을 통한 MEC 서버의 활용은 제한된 배터리 수명이나 계산 능력을 갖는 디바이스들에게 매우 유용하다. 본 논문은 강한 신뢰도가 요구되는 산업 사물인터넷(Industrial IoT, IIoT) 시나리오를 가정하여, 태스크를 실행할 때 발생하는 에너지 소모량과 지연시간을 최적화하며 신뢰도를 보장하는 오프로딩 기법을 제시한다. 본 연구는 실험을 통해 에너지 소모량과 신뢰성 측면에서 제안 기법의 성능을 분석하였다.

• Korean Journal of Microbiology
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• v.36 no.3
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• pp.216-220
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• 2000

Eighty-eight strain3 o~methicillin resistant Stopllylococcus awecis were Isolated from pus (64.7%); spuhm (26.2%), blood, fluid, andurine of 83 patients at Dong-A Hospital in P~~san to invesligate theil-coagulase typ- Ing, and multi-drug resistaut ppattems. The presence of niec A gene confe~~ing melhicillin resistance was tested by polymerase chain reaction (PCR) with uwo mec A gene specific primers using purified clromosonlal DNA as templates. DNA fragments of expected size wel-e detected frorn 86 strains, but not from two strains. !i coagulase typmg, the 86 isolates were assigned to 5 coagulase lypes, I, 11, lll. 1V, VI, VII, VIlI, but there was no isolate helong lo type V. The most abundant coagulase type was type TI(50 %), lollowed by type IV Rest ofthe coagulase types were ininor; ranging fmm 4.5 to 12.5 '% Most of the type I1 ~netlucillin resistant Stapl\ulcorneryiococcus nwem (MRSA) strams were isolated from the generd sulzely ward, but major strains of type IV were Isolated from the otorhinolq~ngology of the hospital's outpatient clinic center. All of the 88 st~nins were sensitive to vancomycin and teicoplanin, but 71 (81%) strains showed multi-drug resitant to penicillin, cephalotl~n, eiythroinycin, gentan~ycin, imipenem, clindamycin, ciprofloxacin and ooxacillin. Yo relationship was found between the antibiotic resistance pattems aud the coagulase typing patterns.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.2
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• pp.514-522
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• 2017

Traffic offloading is a promising solution to solve the explosive growth of mobile traffic. One of offloading schemes, in LIPA/SIPTO(Local IP Access and Selected IP Traffic Offload) offloading, we can offload mobile traffic that can satisfy QoS requirement for application. In addition, it is necessary for traffic offloading using social context due to large traffic from SNS. Thus, we propose the LIPA/SIPTO offloading algorithm using social context. We define the application selection probability using social context, the application popularity. Then, we find the optimal offloading weighting factor to maximize the QoS(Quality of Service) of small cell users in term of effective data rate. Finally, we determine the offloading ratio by this application selection probability and optimal offloading weighting factor. By performance analysis, the effective data rate achievement ratio of the proposed algorithm is similar with the conventional one although the total offloading ratio of the proposed algorithm is about 46 percent of the conventional one.

• Clean Technology
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• v.14 no.3
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• pp.184-192
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• 2008

Fluoride-type cleaning agents such as 2,2,2-trifluoroethanol (TFEA) and hydrofluoroethers (HFEs) do not destroy ozone in the stratosphere and have low global warming potential compared to hydrofluorocarbons(HFCs) and hydrochlorofluorocarbons (HCFCs). Especially, HFEs which have no flash point are paid attention as next generation type of cleaning agents for chlorofluorocarbons (CFCs) since they are safe in handling and have excellent penetration ability compared to hydrocarbon cleaning agents with low flash point. Here, the physical properties and cleaning abilities of fluoride-type cleaning agents such as TFEA, HFE-7100, HFE-7200, HFE-476mec, HFE-449mec-f, AE-3000 and AE-3100E and silicide-type cleaning agents such as trifluoroetoxytrimethylsilane (TFES) and hexamethyldisilazane (HMDS) were measured and compared with those of ozone destruction substances such as CFC-113 and 1,1,1-trichloroethane. They were also compared with toxic methylene chloride (MC) and isopropyl alcohol (IPA) which are now being used as an alternative cleaning agents. As a result, TFEA and HFEs had lower cleaning ability for removal of various soils compared to chloride-type cleaning agents, but they showed excellent cleaning ability fur fluoride-type soils. TFES and HMDS also showed excellent cleaning ability for silicide-type soils.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.29 no.5
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• pp.405-416
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• 2007

Objective : Lots of papers have revealed that tumor growth related factors such as EGF, EGFR, c-erbB-2 play an important role in tumorigenesis and proliferation. These factors are found in most tumors of ectodermal origin. But, documentations of tumor growth related factors on salivary gland tumors were rare. Therefore, we determined expressions of tumor growth related factors; PCNA, p53, EGF, EGFR, cerbB2(HER-2), Maspin, DMBT-1, N-Ras in representative salivary gland tumors. Materials and methods : A few types of salivary tumors were examined by immunohistochemical assays. Each antibody was applied to specimens of tumors. Specimens were composed of 5 pleomorphic adenomas (PA), 3 mucoepidermoid carcinomas (MEC), 2 adenoid cystic carcinomas (ACC) and 2 squamous cell carcinomas (SCC) from 12 patients. One specimen was selected randomly as negative control. For evaluation of staining intensity, each stained sample was divided into 5 grade; no staining, obscure, weak staining, moderate staining, strong staining. Results : Strong expressions of PCNA were found in all tumors except of PA. EGF was expressed strongly in SCC, ACC sequently. But in both PA and MEC, EGF expression was weak. EGFR and c-erbB-2 expression showed similar patterns in all salivary gland tumor tissues. P53 showed weak expression generally in all salivary gland tumors. DMBT-1 was expressed in SCC rather than in ACC or in MEC. N-Ras showed weak expressions in all salivary gland tumors except of squamous cell carcinoma. Conclusion : Taken together, tumor growth related factors were expressed in salivay tumors as well as mucosal squamous cell carcinoma. Especially EGFR and c-erbB-2 could be candidates as diagnostic markers for estimating clinical grade of salivary gland tumors. But further studies with reliable methods will be needed to confirm the results of this study.

• Korean Journal of Head & Neck Oncology
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• v.39 no.1
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• pp.41-44
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• 2023

Mucinous Eccrine carcinoma (MEC) is a rare malignant tumor related to the eccrine sweat gland and is commonly located on the face, especially around the eyelids and scalp. Most of these tumors are diagnosed at age 40's to 60's and exhibit a wide variety of patterns in addition to the general appearance previously reported. MEC is difficult to diagnose clinically, but can be diagnosed by accompanying biopsy. We present the case of a 75-year-old man who complained of a gradually growing Left lower lid tumor of duration one year. Initially, the tumor was mistaken for an epidermal cyst and treated by surgical resection. However, biopsy findings resulted in a diagnosis of Mucinous Eccrine carcinoma. Therefore, we performed wide excision and flap reconstruction surgery. In a one year follow-up examination, the patient achieved successful functional and aesthetic results without regional or distant metastasis and recurrence.

• Journal of Microbiology
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• v.45 no.4
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• pp.350-357
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• 2007

This study was conducted in an effort to evaluate the antimicrobial activity and antibiotic-resistant gene regulation from Saliva miltiorrhiza Bunge on methicillin-resistant Staphylococcus aureus (MRSA). A variety of solvent fractions and methanol extracts of S. miltiorrhiza Bunge were tested in order to determine its antimicrobial activities against S. aureus and MRSA. As a result, the hexane fraction of S. miltiorrhiza Bunge evidenced the highest levels of antimicrobial activity against S. aureus and MRSA. The MICs of the hexane fraction against various MRSA specimens were $64. The hexane fraction evidenced inhibitory effects superior to those of the chloroform fraction. The results showed inhibition zones of hexane (16 mm) and chloroform (14 mm) fractions against MRSA KCCM 40511 at $1,000{\mu}g/disc$. The hexane and chloroform fractions inhibited the expression of the resistant genes, mecA, mecR1, and femA in mRNA. Moreover, the results of Western blotting assays indicated that the hexane and chloroform fractions inhibited the expression of the resistant protein, PBP2a. These results reveal that the hexane and chloroform fractions of S. miltiorrhiza Bunge may prove to be a valuable choice for studies targeted toward the development of new antimicrobial agents.

• Korean Journal of Clinical Laboratory Science
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• v.44 no.3
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• pp.118-123
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• 2012

Nosocomial infection and community-acquired infection with Staphylococcus aureus, especially methicillin-resistant S. aureus (MRSA), has become a strong concern in human body sites and related effects. The aim of this study is investigate the isolation rate of MRSA from nasal cavity inferior regions and cellular phones to assess the risk factor of nosocomial infection and community-acquired infection. 34.7% and 37.2% isolates were MRSA from the nasal cavity inferior regions and cellular phones according to a Mannitol salt agar (added oxacillin $6{\mu}g/mL$) culture and PCR according to S. aureus specific 16S rRNA and mecA primers. Thus, the distribution of S. aureus and the isolation rate of MRSA represent a very high risk factor regards nosocomial infection and community-acquired infection.