• 정보과학회 논문지
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• 제44권9호
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• pp.878-886
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• 2017

본 논문에서는 고성능컴퓨팅 분야에서 주로 활용되는 MPI 응용들을 인텔의 차세대 매니코어 프로세서인 Knights Landing(KNL)에서 실행할 때 발생할 수 있는 성능 병목 현상 및 이를 해결하기 위한 효율적인 자원 할당 방법에 대해서 논의하고자 한다. KNL은 기존의 가속기 형태의 매니코어 프로세서 형태뿐만 아니라 자체적으로 부팅이 가능한 형태의 호스트 프로세서로 구성되어 있으며, 기존의 DDR4 기반의 메모리와 함께 향상된 대역폭을 가진 새로운 형태의 온-패키지 메모리를 장착해서 출시되었다. 이러한 새로운 매니코어 프로세서 아키텍처에 최적화된 자원 할당 방법을 연구함으로써 다중 MPI 응용 실행 성능의 향상과 전체적인 시스템 활용률을 높일 수 있음을 실험적으로 검증하였다.

• Biomolecules & Therapeutics
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• 제21권5호
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• pp.405-410
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• 2013

Codonopsis lanceolata (Campanulaceae) traditionally have been used as a tonic and to treat patients with lung abscesses. Recently, it was proposed that the extract and some compounds isolated from C. lanceolata reversed scopolamine-induced memory and learning deficits. The purpose of this study was to evaluate the improvement of cognitive enhancing effect of C. lanceolata by steam and fermentation process in scopolamine-induced memory impairment mice models by passive avoidance test and Morris water maze test. The extract of C. lanceolata or the extract of steamed and fermented C. lanceolata (SFCE) was orally administered to male mice at the doses of 100 and 300 mg/kg body weight. As a result, mice treated with steamed and fermented C. lanceolata extract (SFCE) (300 mg/kg body weight, p.o.) showed shorter escape latencies than those with C. lanceolata extract or the scopolamine-administered group in Morris water maze test. Also, it exerted longer step-through latency time than scopolamine treated group in passive avoidance test. Furthermore, neuroprotective effect of SFCE on glutamate-induced cytotoxicity was assessed in HT22 cells. Only SFCE-treated cells showed significant protection at 500 ${\mu}g/ml$. Interestingly, steamed C. lanceolata with fermentation contained more phenolic acid including gallic acid and vanillic acid than original C. lanceolata. Collectively, these results suggest that steam and fermentation process of C. lanceolata increased cognitive enhancing activity related to the memory processes and neuroprotective effect than original C. lanceolata.

• 자원환경지질
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• 제29권2호
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• pp.183-192
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• 1996

Much computing time and large computer memory are needed to solve the wave equation in a large complex subsurface layer using finite difference method. The time and memory can be reduced by decreasing the number of grid per minimun wave length. However, decrease of grid may cause numerical dispersion and poor accuracy. In this study, we present 49 points weighted average method which save the computing time and memory and improve the accuracy. This method applies a new weighted average to the coordinate determined by transforming the coordinate of conventional 5 points finite difference stars to $0^{\circ}$ and $45^{\circ}$, 25 points finite differenc stars to $0^{\circ}$, $26.56^{\circ}$, $45^{\circ}$, $63.44^{\circ}$ and 49 finite difference stars to $0^{\circ}$, $18.43^{\circ}$, $33.69^{\circ}$, $45^{\circ}$, $56.30^{\circ}$, $71.56^{\circ}$. By this method, the grid points per minimum wave length can be reduced to 2.5, the computing time to $(2.5/13)^3$, and the required core memory to $(2.5/13)^4$ computing with the conventional method.

• 한국정보처리학회논문지
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• 제5권10호
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• pp.2686-2703
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• 1998

프로세서 메모리 혼합 구조는 해마다 증가하는 프로세서와 메모리간의 성능 격차를 해결하는 대안으로 연구가 활발히 진행되고 있다. 본 논문에서는 프로세서 메모리 혼합 구조의 여러 가지 설계 대안들을 고찰하였다. 이를 위해서 DRAM 접근 시간의 분석적 모델을 제안하고 성능 향상점 및 성능 병목점을 찾았다. 제안한 분석적 모델에 의하여 DRAM 페이지 적중률을 증대하여 성능을 향상시키는 구조로써 새로운 온칩 DRAM 구조인 프리차지 연기 뱅크 아키텍쳐를 제안하였다. 또한 제안한 뱅크 아키텍쳐에 효율적으로 적용할 수 있는 뱅크 인터리빙 방법을 제시하였다. 제안한 구조는 기존의 일반적 DRAM 구조 및 계층적 다중-뱅크 구조보다 우수함을 시뮬레이션을 통하여 증명하였다. 시뮬레이션은 SimpleScalar 툴을 개조하여 사용하였고, SPEC95 벤치마크에 대해서, 캐쉬 메모리의 크기, 뱅크 개수, 프리차지 연기 시간 등의 변화에 대한 성능을 분석하였다.

• 대한한방내과학회지
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• 제41권2호
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• pp.159-165
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• 2020

Introduction: We report a rare case in which the symptoms of hypersomnia were caused by cerebral infarction that occurred in the hypothalamus and hypothalamus. Case Presentation: The patient underwent Korean medicine treatments using Gami-seonghyangjeonggi-san, acupuncture, electroacupuncture, and physical therapy for 37 days. We evaluated the degree of improvement in hypersomnolence based on the amount of sleeping time and the degree of memory impairment with the patient's suggestive conditions as observed by the patient's guardian, and one-sided facial palsy using the Yanagihara Scale. As treatment was applied, sleeping time was decreased from 22 to 9 hours a day. Memory impairment did not show clear improvements as the patient could not recognize others when they visited during the period in which the patient underwent treatment. One-sided facial palsy showed no improvements and there were no changes in the Yanagihara Scale results. Conclusion: This case showed that Korean medicine treatment could be effective to relieve some of the symptoms of thalamus and hypothalamus infarction. Further research is needed to confirm the effectiveness of Korean medicine treatment.

• 성인간호학회지
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• 제29권3호
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• pp.266-277
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• 2017

Purpose: The purpose of this study was to design a mobile-application of a cognitive training program for people who have chemo-related cognitive complaints. Methods: The program was developed based on the network-based instructional system design proposed by Jung. The program consisted of several tasks centered on four cognitive domains: learning, memory, working memory, and attention. For memory learning, a target-image and all its elements (color, position, and number) were presented on the screen that had to be recognized among a number of distractor-figures. In working memory training, the previous learned target-figure according to the level of difficulty had to be remembered among many different figures. In attention training named "Find the same figure," two identical symbols in a grid-pattern filled with different images were presented on the screen, and these had to be simultaneously touched. In attention training named "Find the different figure," a different symbol in a grid pattern filled with same figures had to be selected. This program was developed to train for a minimum of 20 min/day, four days/week for six weeks. Results: This cognitive training revealed statistically significant improvement in subjective cognitive impairments (t=3.88, p=.006) at six weeks in eight cancer survivors. Conclusion: This cognitive training program is expected to offer individualized training opportunities for improving cognitive function and further research is needed to test the effect in various settings.

• 한국정보과학회논문지:시스템및이론
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• 제30권9호
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• pp.461-476
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• 2003

메모리 병목현상의 완화와 구현상의 용이함으로 인해 NUMA 시스템이 지난 수년 동안 전형적인 다중 프로세서 시스템으로 자리를 잡아 왔다. 하지만 NUMA 시스템은 그 구조의 특성상 원격 메모리로의 접근 비율이 커질수록 응답 속도의 지연이 심화되므로, NUMA 시스템의 구현에 있어서 원격 캐쉬의 효율적인 설계를 요구한다. 본 논문에서는 보다 효율적인 원격 캐쉬의 설계를 목표로 하여, 원격 캐쉬 상에서 실제 응용 프로그램의 공유 단위(Granularity of Sharing)의 패턴을 분석하여 원격 캐쉬의 라인 사이즈를 실행 시간에 가상적으로 변화시킬 수 있는“다중 그레인 원격 캐쉬”방식을 제안한다. 그리고 이를 MINT를 통해 모델링한 후 시뮬레이션을 수행하고 그 결과를 분석한다. 시뮬레이션에서는 먼저 Profile-Based 방식을 이용하여 각 응용 프로그램별 최적의 원격 캐쉬 라인 사이즈를 찾아내고, 이를 이용하여 기존의 일반적인 NUMA 시스템에서의 원격 캐쉬와 본 논문에서 제안한 다중 그레인 원격 캐쉬와의 상호 비교를 통해 성능상의 차이점을 비교, 분석한다. 그 후 다중 그레인 원격 캐쉬가 시스템과 응용 프로그램간의 다양한 관계 속에서도 항상 최악의 경우를 피하면서 최적의 경우와 유사한 결과를 가짐을 보인다.

• 대한약침학회지
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• 제20권1호
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• pp.10-17
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• 2017

Objectives: Boswellic acid (BA), a compound isolated from the gum-resin of Boswellia carterii, is a pentacyclic terpenoid that is active against many inflammatory diseases, including cancer, arthritis, chronic colitis, ulcerative colitis, Crohn's disease, and memory impairment, but the mechanism is poorly understood. This study investigated the effects of boswellic acid on spatial learning and memory impairment induced by trimethyltin (TMT) in Wistar rats. Methods: Forty male Wistar rats were randomly divided into 5 groups: Normal group, TMT-administrated rats (8.0 mg/kg, Intraperitoneally, i.p.) and TMT + BA (40, 80 and 160 mg/kg, i.p.)-administrated rats. BA was used daily for 21 days. To evaluate the cognitive improving of BA, we performed the Morris water maze test. Moreover, to investigate the neuroprotective effect of BA, we determined the acetylcholinesterase (AchE) activity, the malondialdehyde (MDA) level as a marker of lipid peroxidation, and the glutathione (GSH) content in the cerebral cortex. Results: Treatment with TMT impaired learning and memory, and treatment with BA at a dose of 160 mg/kg produced a significant improvement in learning and memory abilities in the water maze tasks. Consistent with behavioral data, the activity of AChE was significantly increased in the TMT-injected rats compared to the control group (P < 0.01) whereas all groups treated with BA presented a more significant inhibitory effect against AChE than the TMT-injected animals. In addition, TMT reduced the GSH content and increased the MDA level in the cerebral cortex as compared to the control group) P < 0.01). On the other hand, treatment with BA at 160 mg/kg slightly increased the GSH content and reduced the MDA level in comparison to the TMT-administered group (P < 0.01). Conclusion: The above results suggest that the effect of BA in improving the cognitive function may be mediated through its antioxidant activity.

• 한국전기전자재료학회논문지
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• 제33권6호
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• pp.454-459
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• 2020

In this study, a TiO₂/TiO_2-x-based resistance variable memory was fabricated using a DC/RF magnetron sputtering system and ALD. In order to analyze the effect of oxygen plasma treatment on the performance of resistance random access memory (ReRAM), the TiO₂/TiO_2-x-based ReRAM was evaluated by applying RF power to the TiO_2-x oxygen-holding layer at 30, 60, 90, 120, and 150 W, respectively. The ReRAM was fabricated, and the electrical and surface area performances were compared and analyzed. In the case of ReRAM without oxygen plasma treatment, the I-V curve had a hysteresis curve shape, but the width was very small, with a relatively high surface roughness of the oxygen-retaining layer. However, in the case of oxygen plasma treatment, the HRS/LRS ratio for the I-V curve improved as the applied RF power increased; stable improvement was also noted in the surface roughness of the oxygen-retaining layer. It was confirmed that the low voltage drive was not smooth due to charge trapping in the oxygen diffusion barrier layer owing to the high intensity ReRAM applied with an RF power of approximately 150 W.

• Biomolecules & Therapeutics
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• 제25권3호
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• pp.249-258
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• 2017

To examine the effect of biflorin, a component of Syzygium aromaticum, on memory deficit, we introduced a scopolamine-induced cognitive deficit mouse model. A single administration of biflorin increased latency time in the passive avoidance task, ameliorated alternation behavior in the Y-maze, and increased exploration time in the Morris water maze task, indicating the improvement of cognitive behaviors against cholinergic dysfunction. The biflorin-induced reverse of latency in the scopolamine-treated group was attenuated by MK-801, an NMDA receptor antagonist. Biflorin also enhanced cognitive function in a naïve mouse model. To understand the mechanism of biflorin for memory amelioration, we performed Western blot. Biflorin increased the activation of protein kinase C-${\zeta}$ and its downstream signaling molecules in the hippocampus. These results suggest that biflorin ameliorates drug-induced memory impairment by modulation of protein kinase C-${\zeta}$ signaling in mice, implying that biflorin could function as a possible therapeutic agent for the treatment of cognitive problems.