• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2002년도 춘계 학술대회논문집
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• pp.115-120
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• 2002

A two-dimensional direct numerical simulations was peformed to investigate the flame structure of $CH_4/N_2$-Air counterflow nonpremixed flame interacting with a single vortex. The detailed transport properties and a modified 16-step augmented reduced mechanism based on Miller and Bowman's detailed reaction mechanism were adopted in this calculation. To quantify the strain on flame induced by a vortex, a scalar dissipation rate (SDR) is introduced. Results show that the fuel- and air-side vortex cause an unsteady extinction. In this case, the flame interacting with a vortex is extinguished in much larger SDR than steady flame. It was also found that air- side vortex extinguishes a flame more rapidly than fuel -side vortex.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2248-2253
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• 2008

A numerical study on oscillatory thermocapillary flow in half-zone has performed to understand the effect of axial rotation. 2d unsteady code is developed to observe the onset of oscillation. 2cs Silicone oil with Prandtl number of 26.5 is used as a working fluid. The critical temperature difference at onset of oscillation is investigated under the different aspect ratios and rotation modes. It is shown that the onset of oscillation is delayed when aspect ratio reduces and rotating speed increases. The oscillatory flow is strongly reduced under top rotation and co-rotation modes, while it is augmented under bottom rotation and counter-rotation modes. It is thought that interaction between return flow and bottom wall is important to explain the oscillatory flow.

• Journal of Korean Neurosurgical Society
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• 제60권4호
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• pp.385-390
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• 2017

The doctrine of informed consent, as opposed to medical paternalism, is intended to facilitate patient autonomy by allowing patient participation in the medical decision-making process. However, regrettably, the surgical informed consent (SIC) process is invariably underestimated and reduced to a documentary procedure to protect physicians from legal liability. Moreover, residents are rarely trained in the clinical and communicative skills required for the SIC process. Accordingly, to increase professional awareness of the SIC process, a brief history and introduction to the current elements of SIC, the obstacles to patient autonomy and SIC, benefits and drawbacks of SIC, planning of an optimal SIC process, and its application to cases of an unruptured intracranial aneurysm are all presented. Optimal informed consent process can provide patients with a good comprehension of their disease and treatment, augmented autonomy, a strong therapeutic alliance with their doctors, and psychological defenses for coping with stressful surgical circumstances.

• International Journal of Computer Science & Network Security
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• 제23권10호
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• pp.73-80
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• 2023

The recent growth in the use of mobile devices has contributed to increased computing and storage requirements. Cloud computing has been used over the past decade to cater to computational and storage needs over the internet. However, the use of various mobile applications like Augmented Reality (AR), M2M Communications, V2X Communications, and the Internet of Things (IoT) led to the emergence of mobile cloud computing (MCC). All data from mobile devices is offloaded and computed on the cloud, removing all limitations incorporated with mobile devices. However, delays induced by the location of data centers led to the birth of edge computing technologies. In this paper, we discuss one of the edge computing technologies, i.e., cloudlet. Cloudlet brings the cloud close to the end-user leading to reduced delay and response time. An algorithm is proposed for scheduling tasks on cloudlet by considering VM's load. Simulation results indicate that the proposed algorithm provides 12% and 29% improvement over EMACS and QRR while balancing the load.

• Journal of Positioning, Navigation, and Timing
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• 제5권4호
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• pp.193-202
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• 2016

The Korea Augmentation Satellite System (KASS), which is under development in Korea as a Satellite Based Augmentation System (SBAS) is expected to broadcast SBAS messages to air space in Korea according to the international standards defined by the International Civil Aviation Organization (ICAO) and the Radio Technical Commission for Aeronautics (RTCA). Around 13 SBAS messages are broadcast in every second to transmit augmentation information which can be applicable to a wide area in common. Each of the messages requires a different update interval and time-out according to the characteristics, purpose, and importance of transmitted information, and users should receive and combine multiple SBAS messages to calculate SBAS augmented information. Thus, a time to take acquiring first SBAS position by users differs depending on broadcasting various SBAS messages with which order and intervals. The present paper analyzes the considerations on message scheduling for broadcasting of KASS augmentation information and proposes a design of KASS message scheduler using the considerations. Compared to existing SBAS systems, which have a wide range of service area, a service area of the KASS is limited to Korea only. Thus, the numbers of ionosphere grid points and satellites to be augmented are expected to be smaller than those of existing SBAS. By reflecting this characteristic to the proposed design, shortening of broadcast interval of KASS message is verified compared to existing SBAS and a measure to increase a speed of acquisition of user navigation solution is proposed utilizing remaining message slots. The simulation result according to the proposed measure showed that the maximum broadcast interval can be reduced by up to 20% compared to that of existing SBAS, and users can acquire KASS position solution faster than existing SBAS.

• Tuberculosis and Respiratory Diseases
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• 제67권4호
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• pp.303-310
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• 2009

Background: Elevated expression of cyclooxygenase-2 (COX-2) and Polo-like kinase-1 (PLK-1) is observed in a wide variety of cancers. Augmented expression of COX-2 and enhanced production of prostaglandin $E_2(PGE_2)$ are associated with increased tumor cell survival and malignancy; COX-2 has been implicated in the control of human non-small cell lung carcinoma (NSCLC) cell growth. PLK-1 siRNA induced the cell death of lung cancer cells and the systemic administration of PLK-1 siRNA/atelocollagen complex inhibited the growth of lung cancer in a liver metastatic murine model. COX-2 and PLK-1 are involved in proliferation and in cell cycle regulation, and there is a significant correlation between their interaction in prostate carcinoma. Methods: In this study, we investigated the pattern of COX-2 and PLK-1 expression in NSCLC, after treatment with IL-1$\beta$, COX-2 inhibitor and PLK-1 siRNA. Results: Expression of PLK-1 was decreased in A549 COX-2 sense cells, and was increased in A549 COX-2 anti-sense cells. Knock out of PLK-1 expression by PLK-1 siRNA augmented COX-2 expression in A549 and NCl-H157 cells. When A549 and NCI-H157 cells were treated with COX-2 inhibitor on a dose-dependent basis, PLK-1 and COX-2 were reduced. However, when the expression of COX-2 was induced by IL-1$\beta$, the production of PLK-1 decreased. Conclusion: These results demonstrate that COX-2 and PLK-1 are regulated and inhibited by each other in NSCLC, and suggest that these proteins have a reverse relationship in NSCLC.

• 대한약리학회지
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• 제19권2호
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• pp.1-8
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• 1983

Prostaglandin(PG) is ubiquitously distributed in most mammalian tissue and their actions are complicated. Especially in autonomic nervous system, there are evidences indicating that PGs act as neuromodulators i.e., PGs, which are released in the vicinity of autonomic neuroeffector junctions, influence the release and the response of the neurotransmitter. Present study was undertaken to elucidate the interrelationship between $PGF_{2\alpha}$ and adrenergic ${\alpha}_2-receptor$ function in electrical field stimulation induced contractile response of vas deferens in rat. Male rat, weighing 150{\sim}200\;g, was sacrificed and vas deferens was obtained. The isolated vas deferens strip was placed between two platinum electrodes in temperature controlled $(37^{\circ}C)$ muscle chamber containing Tyrode's solution and the electrical field stimulation(EFS) induced contraction was recorded with Grass Polygraph(Model 7) via force displacement transducer (FT .03, Grass). The results are summarized as follows: 1) Electrical field stimulation for 1sec( 1 msec, 40 cps) induced contraction of vas deferens was completely blocked by tetrodotoxin. 2) Bretylium caused marked inhibition of the EFS-induced contraction, hut tyramine and cocaine augmented the contraction. 3) EFS-induced contraction was inhibited or little affected in distal portion of vas deferens by norepinephrine or methoxamine, but the contraction was rather augmented by the ${\alpha}-agonists$ in proximal portion. 4) Clonidine inhibited the EFS-induced contraction proportionally to the concentration in distal portion, which was blocked by yohimbine pretreatment, but in the presence of $PGF_{2\alpha}$ the blockade by yohimbine was reversed. 5) Indomethacin pretreatment reduced the effect of clonidine, but addition of $PGF_{2\alpha}$ after washing-out the indomethacin caused the contraction to the control level. From these results it is suggested that PG synthesis is a necessary step and the PG itself has a permissive role in ${\alpha}_2-adrenoceptor$ action in rat vas deferens.

• 한국자기학회지
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• 제15권4호
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• pp.217-220
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• 2005

제일원리적 에너지 띠 계산 방법인 전 전자 총 퍼텐셜 선형보강평면파동(all-electron full-potential linearized augmented plane ave) 방법에 일반기울기근사(generalized gradient approximation)를 채용하여 Ag(001) 표면 위에 [110] 방향으로 놓인 Fe 선의 전자구조와 자성을 이론적으로 연구하였다. Fe 선의 원자당 자기모멘트는 $3.02\;{\mu}_B$로 Cu(001) 위에 놓인 Fe[110] 선의 값($2.99\;{\mu}_B$) 보다 약간 컸다. Fe 선의 자기모멘트가 상당히 증가한 것은 이웃한 결합수가 줄어들고 그 결과로 Fe-d 전자상태의 띠폭이 줄어들어 국소화 되고 스핀분리가 증가하였기 때문이다. Fe-d 전자상태의 띠 폭은 약 1.6eV였으며 스핀분리는 약 3.2 eV였다.

• Journal of Microbiology and Biotechnology
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• 제14권1호
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• pp.22-28
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• 2004

Livestock industry requires alternatives of antibiotics to prevent environmental pollution and to maintain public health. We herein report on an effective method to reduce ammonia from livestock manure, and confirmed environmentally-friendly livestock production by adding three types of yeast probiotics, Pichia farinosa SKM-1, Pichia anomala SKM-T, and Galactomyces geotrichum SJM-59, into the feed stuff, separately and/or mixed, and these three types of yeasts were administered to the Hy-line brown layers for 8 weeks. Compared with control, the laying performance, the egg quality, and the number of intestinal lactic acid producing bacteria of the treated group were improved and/or increased significantly. Pichia anomala SKM-T potently reduced ammonia production from poultry manure, and the other strains were also able to reduce the ammonia from it. The optimum condition for the reduction of ammonia with Pichia farinosa SKM-1, Pichia anomala SKM-T, and Galactomyces geotrichum SJM-59 was obtained by using the augmented centroid-simplex design. The ratio of optimum condition was Pichia farinosa SKM-1:Pichia anomala SKM-T:Galactomyces geotrichum SJM-59=0.295:0.209:0.080, and the estimate was -123.36 (p=0.0l38). An ability to reduce the ammonia production from livestock manure was maintained at $30^{\circ}C$ for 15 weeks.

• 전자공학회논문지CI
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• 제47권3호
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• pp.51-58
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• 2010

컴퓨터를 통해 생성된 콘텐츠를 현실 공간에서 자연스럽게 경험할 수 있도록 하는 증강 현실 기술의 등장으로 사용자가 존재하는 실제 공간에서 사용자와 공존하며 사용자 및 실제 객체와 직접적으로 상호작용이 가능한 증강 현실 에이전트에 대한 연구가 진행되고 있다. 본 논문에서는 가상 및 실제 객체가 혼재하는 공간에서 증강 현실 에이전트로 하여금 주변에 존재하는 가상 및 실제 객체를 효율적으로 인지할 수 있도록 하는 지각 주의 모델을 제안한다. 이는 카메라의 시야에 존재하는 실제 및 가상 객체를 인식하고 이를 이용하여 증강 현실 에이전트에게 현재 보이는 실제 및 가상 객체 정보를 추출한다. 그리고 제안한 모델은 에이전트의 목표를 달성하기 위하여 인지된 객체들이 얼마나 유용한지를 추론하고 이들 중 유용한 객체들에게만 에이전트의 주위를 기울이도록 한다. 더 나아가 제안한 모델의 유용성을 확인하기 위하여 캠퍼스 미니어처 내의 빌딩 객체들 사이에 증강되어지며 목표에 관련이 있는 빌딩 객체들에게 관심을 기울이는 증강 캐릭터를 구현하였다. 실험 결과를 통해 제안한 지각 주의 모델은 주변에 존재 하는 가상 및 실제 객체가 동적으로 변하는 환경에서 증강 캐릭터의 지각 부하를 감소시키는 것을 확인할 수 있었다.