• 한국위성정보통신학회논문지
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• 제11권3호
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• pp.32-36
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• 2016

무선 통신 시스템에서 재밍 공격은 통신 성능을 심각하게 저하시킬 수 있는 치명적 위협이다. 특히 반응 재밍은 송신기와 수신기가 통신할 때만 재밍할 수 있기 때문에 반응 재밍을 통해 공격 효율을 극대화할 수 있다. 본 논문에서 반응 재밍의 공격 효과를 저감시키기 위해 multi-input multi-output (MIMO) 기반의 orthogonal frequency-division multiplexing (OFDM) 통신 기술의 특징을 활용하고, 이에 기반한 반복적 채널 추정 알고리즘을 제안하였다. 실험 결과를 통해 본 논문에서 제안한 알고리즘과 기존 항재밍 알고리즘을 비교하였으며, 반응 재밍 공격이 있는 MIMO-OFDM 통신 시스템에서 제안한 알고리즘의 우수성을 입증한다.

• 한국약용작물학회지
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• 제15권5호
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• pp.352-356
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• 2007

The present study was investigated the anti-oxidative effects of aloe vera ingestion on brain and kidney in aged rats by monitoring several oxidative-related parameters. Male specific pathogen-free Fischer 344 rats were randomly divided into four groups of five rat each: Group A was fed test chow without aloe supplementation; Group B was fed a diet containing a 1% freeze-dried aloe filet; Group C was fed a diet containing a 1% charcoal-processed, freeze-dried aloe filet; and Group D was fed a diet containing a charcoal-processed, freeze-dried, whole leaf aloe in drinking water. Analyses of tissues were done at 4 months and 16 months of age. Results showed that a long-term intake of aloe, regardless of the preparation used, enhanced antioxidant defenses against lipid peroxidation, as indicated by reduced phosphatidylcholine hydroperoxide levels in both brain and kidney. The additional benefit of aloe intake on the anti-oxidative action was evidenced by enhanced superoxide dismutase and catalase activity in all aloe-ingested groups. Another beneficial effect of aloe shown in this study, although not an anti-oxidative parameter, was its cholesterol-lowering effect as detected in brain and kidney with significant decreases at age16 months of aloe-fed rats. Based on these findings, we conclude that a long-term dietary aloe supplementation modulated the anti-oxidative defense systems and cholesterol level.

• 한국잠사곤충학회지
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• 제22권2호
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• pp.8-12
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• 1981

인공사료사육에 있어서 핵다각체바이러스에 대한 품종별 저항성을 검토하기 위해서 7개의 장려품종을 공시해서 그 죽은 누에 비율을 조사한 결과는 다음과 같다. 1. 인공사료에 기른 누에에 핵다각체를 접종했을 때 바이러스의 $10^{7}$ /$m\ell$의 높은 농도를 적용할 경우에는 품종, 령기에 관계없이 대부분 거의 발병하는 높은 치사율을 나타냈으며 $10^{6}$/$m\ell$의 경우도 같은 경향으로 높은 발병률을 보였다. 2. 바이러스의 농도가 $10^{5}$/$m\ell$~$10^3$/$m\ell$의 낮은 농도에서는 바이러스에 대한 감수성에 있어서 품종간에 차이를 보여주었다. 잠111$\times$잠112와 한생1호$\times$한생2호는 각령기의 처리에 있어서 다른 품종보다 치사율이 낮음으로써 낮은 감수성을 보여주었다. 3. 어느 품종에 있어서나 일반적으로 2령때가 3령때보다 바이러스에 대한 감수성이 높았다.다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2012년도 추계학술대회
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• pp.128-130
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• 2012

One of the hot issues on GNSS might be that China declared to broadcast the signal of the new Global Navigation Satellite System called Beidou-Compass in December 2011. The multi-GNSS systems with the existing GPS and GLONASS consist of more than 100 GNSS satellites and transmit their signals in near future. Many benefits are expected in accuracy, availability, integrity and increasing anti-jam performance. In this presentation, we have mainly investigated the latest issue for multi- GNSS and discussed spectrum analysis as well as the accuracy improvement issue. The use of the modern weapon system based on satellite navigation information was also briefly investigated in warfare.

• 한국축산식품학회지
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• 제35권4호
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• pp.507-514
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• 2015

Deer velvet antler (DVA) is one of the most popular medicines in China. Numerous studies have demonstrated that velvet antler possess biological effects. However, data regarding its anti-migration activity on prostate cancer is scarce. In this study, we investigated the inhibitory effect of top DVA (T-DVA) on the expression of prostate-specific antigen (PSA) and migration-related genes in the human prostate cancer cell, LNCaP. The T-DVA down-regulated the expression of PSA. In addition, the Radius^TM assay revealed that T-DVA inhibited the migration behavior of prostate cancer cells. Furthermore, the expression of matrix metalloproteinase (MMP)-9 and vascular endothelial growth factor (VEGF) was also decreased with T-DVA. On the contrary, T-DVA increased the tissue inhibition of metallo-proteinase (TIMP)-1 and (TIMP)-2. Taken together, our findings indicate that the T-DVA possesses anti-migration activity on prostate cancer cells. This is the first study of DVA to report the anti-migration activity on prostate cancer.

• 한국축산식품학회지
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• 제31권3호
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• pp.349-355
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• 2011

Russian deer velvet antlers were divided into three parts and subjected to a extraction process using hot water at 100, 110, and $120^{\circ}C$ or an extraction with 70% ethanol. Each extract was analyzed for its biochemical components, including uronic acid, sulfated-glycosaminoglycans (sulfated-GAGs), and sialic acid, and the antioxidant and anti-acetylcholinesterase activities were investigated. Different levels of uronic acid and sulfated-GAGs were observed in the extracts according to the water temperature used for the extraction, and contents decreased with increasing extraction temperature. The upper layer of each extract showed high amounts of uronic acid and sulfated-GAGs, followed by the middle and base layers. Ethanol extraction was more effective for recovering uronic acid than sulfated-GAGs. Sialic acid content was the highest in the $110^{\circ}C$ extracts but was not observed in the ethanol extracts. Velvet antler extracts showed strong antioxidant activities against DPPH and hydrogen peroxide as well as strong reducing power in a dose-dependent manner. However, the antioxidant activities were different in each layer and according to the extraction method. Additionally, velvet antler extracts exhibited inhibitory activity against acetylcholinesterase, which is associated with Alzheimer's disease, in a dose-dependent manner. These results suggest that velvet antler extracts are useful as a functional food ingredient and/or a pharmaceutical.

• 한국식품영양과학회지
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• 제43권12호
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• pp.1808-1816
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• 2014

본 연구는 삼채의 뿌리와 잎을 물과 주정을 이용하여 추출하여 항산화 활성 및 항염증 효과를 비교 평가하였다. 삼채의 추출물에 포함된 총 폴리페놀 함량과 전자스핀공명기기를 이용한 DPPH, alkyl, hydroxyl 라디칼 소거능, ABTS를 이용한 라디칼 소거 활성 및 FRAP 및 ORAC을 이용한 항산화 활성을 평가하였는데, 삼채뿌리 추출물보다는 삼채잎 추출물의 항산화 활성이 높았으며 이는 잎에 포함된 총 폴리페놀 함량과 관련이 있을 것으로 판단된다. 물 추출의 경우가 뿌리와 잎 모두 수율이 높았으며 폴리페놀 함량과 ORAC value와 alkyl 라디칼 소거 활성은 비슷한 경향을 나타내었으나 DPPH와 hydroxyl 라디칼 소거 활성과는 다른 결과를 나타내었다. 또한 간세포를 이용한 세포 독성 평가 실험 수행 결과, 0.25 mg/mL의 농도까지는 삼채의 뿌리와 잎의 물 추출물 및 주정 추출물 모두 독성을 나타내지 않았다. RAW264.7 세포를 이용하여 독성을 나타내지 않는 농도인 0.2 mg/mL 이하에서 항염증 활성 평가를 수행한 결과 삼채뿌리 및 삼채잎의 물과 주정 추출물은 모두 NO의 생성을 농도 의존적으로 감소시키는 경향을 나타내었다. 뿐만 아니라 삼채 추출물은 염증성 사이토카인인 IL-6와 TNF-${\alpha}$의 생성을 감소시켰으며, 특히 삼채뿌리 물 추출물은 가장 높은 IL-6와 TNF-${\alpha}$의 생성 억제를 나타내었다. 또한 삼채 추출물이 LPS로 유도한 세포내 활성산소종을 농도 의존적으로 억제하는 것을 확인하였으며, 위의 결과로 삼채잎 추출물은 항산화 활성이 우수하고 삼채뿌리 추출물은 항염증 활성이 높음을 확인하였다. 따라서 삼채 추출물이 우수한 항산화 및 항염증 활성을 가지고 있는 것으로 판단되며, 이와 관련된 항산화 및 항염증 생리활성 물질에 관한 추가적인 연구가 필요할 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제26권1호
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• pp.28-37
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• 2016

Numerous plants have been documented to contain phenolic compounds. Thymol is one among these phenolic compounds that possess a repertoire of pharmacological activities, including anti-inflammatory, anticancer, antioxidant, antibacterial, and antimicrobial effects. Despite of the plethora of affects elicited by thymol, its activity profile on gastric cancer cells is not explored. In this study, we discovered that thymol exerts anticancer effects by suppressing cell growth, inducing apoptosis, producing intracellular reactive oxygen species, depolarizing mitochondrial membrane potential, and activating the proapoptotic mitochondrial proteins Bax, cysteine aspartases (caspases), and poly ADP ribose polymerase in human gastric AGS cells. The outcomes of this study displayed that thymol, via an intrinsic mitochondrial pathway, was responsible for inducing apoptosis in gastric AGS cells. Hence, thymol might serve as a tentative agent in the future to treat cancer.

• 원예과학기술지
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• 제31권4호
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• pp.496-502
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• 2013

Grapes (Vitis vinifera) are one of the most important fruits worldwide and are eaten raw or after conversion to jelly, jam, juice and wine. Grape skins are a major source of resveratrol (3,5,4'-trihydroxystilbene), which has the ability to reduce blood sugar as well as anticancer, anti-inflammatory, and other beneficial cardiovascular effects. In this study, we investigated the increased accumulation of resveratrol in grape skin and leaves following ultrasonication treatment, which has been shown to induce resveratrol accumulation in several plants. Various ultrasonication treatment times and incubation periods were employed to identify the optimum conditions for the maximum accumulation of resveratrol. Treatment and further incubation led to increased resveratrol in both grape skins and leaves, with the highest increases of 7.7-fold and 1.9-fold occurring in response to 5 min ultrasonication treatment followed by 6 hour incubation and 15 min ultrasonication treatment followed by 3 hour incubation, respectively. The underlying mechanism for the increased amounts of resveratrol were studied by employing a semi-quantitative RT-PCR to monitor the expression levels of the resveratrol synthase (RS) gene in response to ultrasonication treatment. The RS gene increased the expression in response to ultrasonication treatment, suggesting that up-regulation of the RS gene by ultrasonication treatment triggers increased amounts of resveratrol. Taken together, these data indicate that this simple ultrasonication treatment of grapes can be an efficient post-harvest technology for increasing resveratrol in grape skins in addition to cleaning the fruits.

• 한국군사과학기술학회지
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• 제5권2호
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• pp.185-194
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• 2002

본 논문에서는 jammer를 향하여 호밍하는 대함 유도탄에 대하여 적용할 수 있는 피동 거리추정필터를 제안하였다. 최근의 jammer는 상당히 먼 거리에서 jamming이 가능하므로, 제안된 필터는 필터 초기치 오차가 큰 경우에도 이를 신속히 제거하고 잘 동작할 수 있도록 설계되었다. 함대함 유도탄의 경우, 표적에 비하여 유도탄의 운동이 훨씬 주도적이므로 교전상황은 상대거리와 시선변화율을 상태변수로 하는 2차 시스템으로 모델링이 가능하다. 본 논문에서는 이와같은 2차 모델에 근거한 확장칼만필터를 구성하고, 최소자승법을 이용한 초기치 오차 추정 알고리듬을 부가함으로써 새로운 피동 거리추정필터를 유도하였다. 제안된 필터는 필터의 초기치 오차가 상당히 큰 경우에도 적은 계산량으로 우수한 거리추정성능을 보여주었다.