• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제7권5호
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• pp.539-547
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• 2001

클러스터 시스템의 성능을 향상시키기 위해서는 Myrinet과 같은 고성능 통신망 인터페이스가 필수적이다. 그러나 Myrinet에서 동작하는 저수준 통신 계층들은 각기 고유한 통신 방식을 사용하므로 호환성이 떨어진다. 따라서 MPI와 같은 통신 프로그래밍 표준을 효율적으로 구현하여 응용프로그램 수준에서 고성능과 호환성을 동시에 제공하여야 한다. 본 논문에서는 VMMC 통신 계층을 기반으로 MPI를 구현하였다. VMMC의 직접 저장 방식은 MPI의 Send/Recv 방식을 지원하기에 적합하지 않지만 본 논문에서는 두 가지 통신 방식을 변화하기 위한 송수신 큐 구조를 설계하고 늦은 위치 갱신, 선택적 무복사 전송 등의 최적화 기법을 적용함으로써 높은 전송성능을 얻는다. MPI-VMMC의 최대 전송 대역폭은 90.7Mbytes/sec이며 이는 VMMC 통신 계층의 최대 전송 성능의 95%에 달한다.

• 공업화학
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• 제22권3호
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• pp.308-311
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• 2011

하수슬러지 촤에 MnOx를 담지한 촉매를 사용하여 $NH_3$를 환원제로 하는 선택적 촉매 환원반응의 반응 메커니즘 분석을 수행하였다. XRD 분석 결과 활성 Mn phase는 $Mn_3O_4$인 것으로 여겨졌다. 또한 $150^{\circ}C$ 이하에서는 흡착반응이 주요한 질소산화물 저감 메커니즘으로 작동하였으나, $100{\sim}150^{\circ}C$에서는 환원반응도 질소산화물 저감에 관여하는 것으로 보여졌다. 실험결과에 기초하여 활성 촤와 여기에 MnOx를 담지한 촤에서의 반응속도상수를 비교하였다. MnOx 담지촤는 높은 충돌계수와 낮은 활성화 에너지에 기인하여 높은 반응속도 상수와 높은 NOx 제거 효율을 나타내었다. 두 가지 촤 모두 본 실험 조건하에서 활성화 에너지는 상대적으로 낮았다(10~12 kJ/mol).

• Journal of Ginseng Research
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• 제42권1호
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• pp.107-115
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• 2018

Background: Depression is one of the most commonly diagnosed neuropsychiatric diseases, but the underlying mechanism and medicine are not well-known. Although Panax ginseng has been reported to exert protective effects in various neurological studies, little information is available regarding its antidepressant effects. Methods: Here, we examined the antidepressant effect and underlying mechanism of P. ginseng extract (PGE) in a chronic restraint stress (CRS)-induced depression model in mice. Results: Oral administration of PGE for 14 d decreased immobility (depression-like behaviors) time in forced swim and tail suspended tests after CRS induction, which corresponded with attenuation of the levels of serum adrenocorticotropic hormone and corticosterone, as well as attenuated c-Fos expression in the amygdala. PGE enhanced messenger RNA expression level of brain-derived neurotrophic factor but ameliorated microglial activation and neuroinflammation (the level of messenger RNA and protein expression of cyclooxygenase-2 and inducible nitric oxide synthase) in the amygdala of mice after CRS induction. Interestingly, 14-d treatment with celecoxib, a selective cyclooxygenase-2 inhibitor, and $N_{\omega}$-nitro-L-arginine methyl ester hydrochloride, a selective inducible nitric oxide synthase inhibitor, attenuated depression-like behaviors after CRS induction. Additionally, PGE inhibited the upregulation of the nuclear factor erythroid 2 related factor 2 and heme oxygenase-1 pathways. Conclusion: Taken together, our findings suggest that PGE exerts antidepressant-like effect of CRS-induced depression by antineuroinflammatory and antioxidant (nuclear factor erythroid 2 related factor 2/heme oxygenase-1 activation) activities by inhibiting the hypothalamo-pituitary-adrenal axis mechanism. Further studies are needed to evaluate the potential of components of P. ginseng as an alternative treatment of depression, including clinical trial evaluation.

• 스마트미디어저널
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• 제8권2호
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• pp.58-65
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• 2019

문서 자동 요약은 주어진 문서로부터 주요 내용을 추출하거나 생성하는 방식으로 축약하는 작업을 말한다. 최근 연구에서는 대량의 문서를 딥러닝 기법을 적용하여 요약문 자체를 생성하는 방식으로 발전하고 있다. 생성 요약은 미리 생성된 위드 임베딩 정보를 사용하는데, 전문 용어와 같이 저빈도 핵심 어휘는 입베딩 된 사전에 없는 문제가 발생한다. 인코딩-디코딩 신경망 모델의 문서 자동 요약에서 미등록 어휘의 출현은 요약 성능 저하의 요인이다. 이를 해결하기 위해 본 논문에서는 요약 대상 문서에서 새로 출현한 단어를 복사하여 요약문을 생성하는 방법을 사용한다. 기존의 연구와는 달리 정확한 포인팅 정보와 선택적 복사 지시 정보를 명시적으로 제공하는 방법으로 제안하였다. 학습 데이터는 논문의 초록과 제목을 대상 문서와 정답 요약으로 사용하였다. 제안한 인코딩-디코딩 기반 모델을 통해서 자동 생성 요약을 수행한 결과 단어 제현 기반의 ROUGE-1이 47.01로 나타났으며, 또한 어순 기반의 ROUGE-L이 29.55로 향상되었다.

• Journal of Mechanical Science and Technology
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• 제20권1호
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• pp.1-12
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• 2006

This work reviews the effects of catalyst formulation and exhaust gas composition on soot oxidation in CDPF (Catalytic Diesel Particulate Filter). DOC's (Diesel Oxidation Catalysts) have been loaded with Pt catalyst (Pt/$Al_{2}O_3$) for reduction of HC and CO. Recent CDPF's are coated with the Pt catalyst as well as additives like Mo, V, Ce, Co, Fe, La, Au, or Zr for the promotion of soot oxidation. Alkali (K, Na, Cs, Li) doping of metal catalyst tends to increase the activity of the catalysts in soot combustion. Effects of coexistence components are very important in the catalytic reaction of the soot. The soot oxidation rate of a few catalysts are improved by water vapor and NOx in the ambient. There are only a few reports available on the mechanism of the PM (particulate matter) oxidation on the catalysts. The mechanism of PM oxidation in the catalytic systems that meet new emission regulations of diesel engines has yet to be investigated. Future research will focus on catalysts that can not only oxidize PM at low temperature, but also reduce NOx, continuously self-cleaning diesel particulate filters, and selective catalysts for NOx reduction.

• The Journal of Korean Physical Therapy
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• 제15권2호
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• pp.75-84
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• 2003

The purpose of this study was to review of mechanism and application methodology about mental practice. The mental practice is symbolic rehearsal of physical activity in the absence of any gross muscular movements. Human have the ability to generate mental correlates of perceptual and motor events without any triggering external stimulus, a function known as imagery, Practice produces both internal and external sensory consequences which are thought to be essential for learning to occur, It is for this reason that mental practice, rehearsal of skill in imagination rather than by overt physical activity, has intrigued theorists, especially those interested in cognitive process. Several studies in sport psychology have shown that mental practice can be effective in optimizing the execution of movements in athletes and help novice learner in the incremental acquisition of new skilled behaviors. There are many theories of mental practice for explaining the positive effect In skill learning and performance. Most tenable theories are symbolic learning theory, psyconeuromuscular theory, Paivio's theory, regional cerebral blood flow theory, motivation theory, modeling theory, mental and muscle movement nodes theory, insight theory, selective attention theory, and attention-arousal set theory etc.. The factors for influencing to effects of mental practice are application form, application period, time for length of the mental practice, number of repetition, existence of physical practice.

• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1999년도 PROCEEDINGS OF 99 INTERNATIONAL CONFERENCE OF THE KACG AND 6TH KOREA·JAPAN EMG SYMPOSIUM (ELECTRONIC MATERIALS GROWTH SYMPOSIUM), HANYANG UNIVERSITY, SEOUL, 06월 09일 JUNE 1999
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• pp.115-127
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• 1999

The charged clusters or particles, which contain hundreds to thousands of atoms or even more, are suggested to form in the gas phase in the thin film processes such as CVD, thermal evaporation, laser ablation, and flame deposition. All of these processes are also used in the gas phase synthesis of the nanoparticles. Ion-induced or photo-induced nucleation is the main mechanism for the formation of these nanoclusters or nanoparticles inthe gas phase. Charged clusters can make a dense film because of its self-organizing characteristics while neutral ones make a porous skeletal structure because of its Brownian coagulation. The charged cluster model can successfully explain the unusual phenomenon of simultaneous deposition and etching taking place in diamond and silicon CVD processes. It also provides a new interpretation on the selective deposition on a conducting material in the CVDd process. The epitaxial sticking of the charged clusters on the growing surface is gettign difficult as the cluster size increases, resulting in the nanostructure such as cauliflowr or granular structures.

• Bulletin of the Korean Chemical Society
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• 제26권2호
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• pp.281-284
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• 2005

The Fe/MgO catalysts with different Fe loadings (1, 4, 6, 15 and 30 wt% Fe) were prepared by a wet impregnation with iron nitrate as precursor. All of the catalysts were characterized by BET surface analyzer, X-ray diffraction (XRD), temperature-programmed reduction (TPR), and X-ray photoelectron spectroscopy (XPS). The maximum removal capacity of $H_2S$ was obtained with 15 wt% Fe/MgO catalyst which had the highest BET surface area among the measured catalysts. XRD of Fe/MgO catalysts showed that well dispersed Fe particles could be present on Fe/MgO with Fe loadings below 15 wt%. The crystallites of bulk $\alpha$-$Fe_2O_3$ became evident on 30 wt% Fe/MgO, which were confirmed by XRD. TPR profiles showed that the reducibility of Fe/MgO was strongly related to the loaded amounts of Fe on MgO support. Therefore, the highest removal efficiency of $H_2S$ in wet oxidation could be ascribed to a good dispersion and high reducibility of Fe/MgO catalyst. XPS studies indicated that the $H_2S$ oxidation with Fe/MgO could proceed via the redox mechanism ($Fe^{3+}\;{\leftrightarrow}\;Fe^{2+}$).

• 공업화학
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• 제3권4호
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• pp.717-721
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• 1992

공침법으로 제조한 vanadium molybdate와 copper molybdat촉매의 기계적 혼합물과 $V_2O_5$와 $MoO_3$의 기계적 혼합물을 아크로레인의 선택 산화반응용 촉매로 사용하여 각각의 금속산화물 사이의 상승효과에 대하여 고찰하였다. 반응실험 결과 혼합촉매를 사용한 경우 아크로레인의 전화율과 아크릴산의 수율이 증가하였으며 이는 remote control mechanism으로 설명할 수 있었다. 열중량 분석결과 혼합촉매에서 격자산소가 방출됨을 확인할 수 있었다.

• Biomolecules & Therapeutics
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• 제20권6호
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• pp.506-512
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• 2012

Although pruritus is the critical symptom of atopic dermatitis that profoundly affect the patients' quality of life, controlling and management of prurirtus still remains as unmet needs mainly due to the distinctive multifactorial pathogenesis of pruritus in atopic dermatitis. Based on the distinct feature of atopic dermatitis that psychological state of patients substantially influence on the intensity of pruritus, various psychotropic drugs have been used in clinic to relieve pruritus of atopic dermatitis patients. Only several psychotropic drugs were reported to show real antipruritic effects in atopic dermatitis patients including naltrexone, doxepin, trimipramine, bupropion, tandospirone, paroxetine and fluvoxamine. However, the precise mechanisms of antipruritic effect of these psychotropic drugs are still unclear. In human skin, serotonin receptors and serotonin transporter protein are expressed on skin cells such as keratinocytes, melanocytes, dermal fibroblasts, mast cells, T cells, natural killer cells, langerhans cells, and sensory nerve endings. It is noteworthy that serotonergic drugs, as well as serotonin itself, showed immune-modulating effect. Fenfluramine, fluoxetine and 2, 5-dimethoxy-4-iodoamphetamine significantly decreased lymphocyte proliferation. It is still questionable whether these serotonergic drugs exert the immunosuppressive effects via serotonin receptor or serotonin transporter. All these clinical and experimental reports suggest the possibility that antipruritic effects of selective serotonin reuptake inhibitors in atopic dermatitis patients might be at least partly due to their suppressive effect on T cells. Further studies should be conducted to elucidate the precise mechanism of neuroimmunological interaction in pruritus of atopic dermatitis.