• 대한전자공학회논문지TC
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• 제43권6호
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• pp.46-52
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• 2006

본 논문에서는 70-nm metamorphic high electron mobility transistor (MHEMT)와 W-band 마이크로 머시닝 링 커플러를 이용하여 낮은 변환손실 및 높은 격리특성의 94 GHz MMIC 믹서를 설계 및 제작하였다. 놀은 LO-RF 격리도 특성을 얻기 위하여 마이크로 머시닝 링 커플러를 사용한 새로운 3차원 구조의 resistive 믹서 구조를 제안하였다. 제작된 93 GHz MMIC 믹서는 94 GHz에서 8.9 dB의 낮은 변환 손실과 29.3 dB의 높은 LO-RF 격리돈 특성을 나타내었다. 본 논문에서 제안된 믹서는 기존의 보고된 W-band 대역 믹서와 비교하여 양호한 변환 손실 뿐 만 아니라 우수한 LO-RF 격리도 특성을 나타내었다.

• 한국식생활문화학회지
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• 제13권4호
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• pp.363-381
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• 1998

Food goods traded between Korea and Japan during the middle period of the Cho Sun era included Insam (Jinseng), rice, beans, honey, perilla oil, starch, adlay, walnuts, pine nuts, jujubes, hazelnuts, and dired chestnuts as exports ; and pepper as imports. The number of Japanese envoies that visited regularly was one thousand five hundred people a year. The receptions that were held for them during the middle period equaled those of the first term of the Cho Sun era, but these receptions were only held in Pu-san. The expense of daily meals was broken down into 8 grades ranging from \129,300 to 2133. The daily meals included Jo-ban (breakfast), Jo-seok-ban (breakfast and dinner), and Ju-jeom-shim (lunch) for the Japanese who visited regularly. During the course of a year, the total amount spent on daily meals was put at a billion won. The banquet style meals included Ha-seon-da-rye (a welcome tea party), Ha-seon-yeon (a welcome banquet), No-cha-yeon (a banquet that was held on the street), and Ye-dan-da-rye (a drink banquet that was held when silk was offered as a gift). It also included Byeol-yeon (a banquet out of the dordinary), Sang-seon-yeon (a farewell banquet), and Myong-il-yeon (a banquet that was held on a national holiday). The banquet style meals were composed of Ceon-tack (to set a table for dinner), Sang-hwa (a flower that was put on the food), Kwan-hwa (to offer a flower when a banquet was held), Ju-9-jan (the ninth wine glass), Dae-seon (meat), music, and Jung-bae-rye (a banquet that was held again after a banquet). The Cho Sun government held banquets forty five times for the Japanese, the food expense for the banquets was put at two hundred and thirty million won.

• BMB Reports
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• 제44권10호
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• pp.659-664
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• 2011

As part of the search for biologically active anti-osteoporotic agents that enhance differentiation and mineralization of osteoblastic MC3T3-E1 cells, we identified the ginsenoside Rh2(S), which is an active component in ginseng. Rh2(S) stimulates osteoblastic differentiation and mineralization, as manifested by the up-regulation of differentiation markers (alkaline phosphatase and osteogenic genes) and Alizarin Red staining, respectively. Rh2(S) activates p38 mitogen-activated protein kinase (MAPK) in time- and concentration-dependent manners, and Rh2(S)-induced differentiation and mineralization of osteoblastic cells were totally inhibited in the presence of the p38 MAPK inhibitor, SB203580. In addition, pretreatment with Go6976, a protein kinase D (PKD) inhibitor, significantly reversed the Rh2(S)-induced p38 MAPK activation, indicating that PKD might be an upstream kinase for p38 MAPK in MC3T3-E1 cells. Taken together, these results suggest that Rh2(S) induces the differentiation and mineralization of MC3T3-E1 cells through activation of PKD/p38 MAPK signaling pathways, and these findings provide a molecular basis for the osteogenic effect of Rh2(S).

• 한국균학회지
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• 제47권4호
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• pp.407-416
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• 2019

A common post-harvest disease of sweetpotato tuber is root rot caused by Fusarium solani in Korea as well as the other countries. Storage root rot disease was monitored earlier on sweetpotato (Ipomoea batatas) in storehouses of different locations in Korea. In the present study, an isolate SPL16124 was choosen and collected from Sweetpotato Research Lab., Bioenergy Crop Research Institute, NICS, Muan, Korea, and confirmed the identification as Fusarium solani by conidial and molecular phylogenetic analysis (internal transcribed spacer ITS and translation elongation factor EF 1-α gene sequences). The isolate was cultured on potato dextrose agar, and conidiation was induced. The fungus was screened for Fusarium root rot on tuber of 14 different varieties. Among the tested variety, Yenjami, Singeonmi, Daeyumi, and Sinjami showed resistant to root rot disease. Additionally, the pathogen was tested for pathogenicity on stalks of these varieties. No symptom was observed on the stalk, and it was confirmed that the disease is tissue specific.

• 한국미생물·생명공학회지
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• 제9권2호
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• pp.65-69
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• 1981

농산폐자원을 이용하기 위한 방법으로써 Trichoderma sp. KI 7-2로 만든 koji와 내열성 효모를 사용하여 동시당화-발효와 당화액 발효를 비교하였다. 볏짚의 당화액에서는 15 mg/$m\ell$의 cellobiose가 존재하였으나 동일한 효소원을 사용한 동시당화-발효액에서는 존재하지 않았다. 효소당화법에서 는 cellulase enzyme system의 반응산물인 glucose가 cellobiose의 활성을 저해하므로 cellobiose 가 축적되었으나 동시당화-발효법에서 는 glucose가 ethanol로 발효되어 cellobiose의 축적이 없었다. Cutting mill 한 볏짚은 동시 당화-발효 과정에서는 ball mill 한 것과 같은 정도로 효과적으로 발효되었다. 이 결과로부터 cellylolytic enzyme system의 반응산물에 의한 저해 mechanism을 논의하였다. 또한 볏짚 당화시 약 10 mg/$m\ell$ 생산되는 xylose는 동시당화-발효에 아무런 영향을 미치지 않음을 확인하였다.

• 대한한의학회지
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• 제26권4호
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• pp.22-30
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• 2005

Objectives: Recently, angiogenesis has gained an increasing interest as a prognostic factor in breast cancer. In this study we aimed to assess the anti angiogenic effects of HAD, a botanical anticancer remedy which has been prescribed in Daejeon University Oriental Hospital in Korea, on patients with breast carcinoma by measuring the serum vascular endothelial growth factor (VEGF), basic fibroblast growth factor (b-FGF) and platelets levels. Methods: The study included 26 consecutive breast cancer patients (mean age$\pm$standard deviation: 47.5$\pm$8.7 years) with stage II to IV disease who were treated with HAD (mean duration $\pm$ standard deviation: 264.5$\pm$121.6 days). In addition to routine laboratory and staging procedures, serum VEGF, b-FGF levels and platelet counts were determined as antiangiogenic markers. The antiangiogenic effects of HAD were evaluated by analyzing the differences between the values of the antiangiogenic markers before and after the treatment with HAD. Results: Serum b-FGF concentrations were significantly reduced after the treatment with HAD (P=0.042). Serum VEGF concentrations were found to have a somewhat decreasing change, though the change was not statistically significant (P=0.229). Platelet counts had little changes (P=O.80). Conclusions: It is supposed that HAD has effects on decreasing the serum b-FGF levels related with the clinical outcome of breast cancer patients.

• Journal of the Korean Wood Science and Technology
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• 제45권5호
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• pp.572-579
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• 2017

WPC 내 목질섬유 함량 분석은 신뢰도 높은 목재 플라스틱 복합재(WPC) 소비시장 형성을 위해 상당히 중요하다. 본 연구에서는 polypropylene과 목질섬유를 복합화한 단순 WPC 배합 조건에서 WPC 내 목질섬유 함량에 대한 분석을 TGA를 이용한 열분석 방법과 AMS를 이용한 바이오 탄소 함량 분석 방법을 통해 진행하였다. TGA를 통한 열분해 분석법은 $5^{\circ}C/min$의 승온속도로 고분자 PP의 최대 미분 온도를 이용하여 신뢰도 높은 WPC 내 목질섬유 함량에 관한 검량선을 얻을 수 있었다. TGA와 AMS의 분석 방법 비교에 있어서는, 바이오 탄소 함량을 이용하는 AMS 분석법이 더 높은 신뢰성을 보여주었다.

• 대한수의학회지
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• 제51권1호
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• pp.29-35
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• 2011

Lack of hygiene and puerperal mastitis are common causes of bacterial diseases in nursing neonates. The aim of this study was to isolate microorganisms from milk samples of healthy female Jindo dogs with suckling puppies and to investigate antimicrobial susceptibility against the isolated bacteria. Milk samples were collected from 120 udders of 12 lactating Jindo dogs that were 2~4 years old without any clinical diseases including mastitis. Bacteria were isolated from 64 milk samples (53.3%), either singly (76.6%) or in combination (23.4%). Staphylococcus (S.) spp. was the most common microorganisms (74.7%) isolated from canine milk, followed by Haemophillus spp. (10.9%), Streptococcus spp. (9.6%), Gardnerella spp. (2.4%) and Moraxella spp. (2.4%). The most frequently isolated organism was S. warneri (31.3%). Antimicrobial susceptibility of these bacteria was tested with 17 antimicrobial agents by Kirbyand Bauer standardized disc diffusion method. Results indicated that bacteria isolated from healthy canine milk were mostly susceptible to amoxicillin-clavulanic acid, cephalothin and ceftiofur, but were resistant to erythromycin, neomycin and tetracycline.

• 한국항공우주학회지
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• 제38권4호
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• pp.327-334
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• 2010

최근 개발된 항공기는 대부분 디지털 Fly-By-Wire(FBW) 혹은 광신호를 사용하는 Fly-By-Light(FBL) 시스템을 사용하고 있다. 이러한 시스템들은 조종사의 직접 조종으로는 불가능하거나 어려운 복잡한 임무의 수행, 비행범위 확장, 신뢰성 향상 등의 장점을 가지고 있다. FBW 기술을 적용한 비행제어기술이 발전됨에 따라 운항 시 안정성 확보 및 보다 효율적인 임무수행을 위해 비행영역(Flight Envelope) 보호의 개념이 항공기 설계에 있어 중요한 문제로 부각되고 있다. 본 논문에서는 dynamic trim 알고리즘, peak response estimation, 제어이득 스케쥴링 등의 방법을 이용해서 항공기의 비행영역 보호를 수행하고, 각 방법의 성능을 비교하여 최적의 제어기를 설계하는 연구를 수행하였다.

• 한국통신학회논문지
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• 제30권7A호
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• pp.578-586
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• 2005

본 논문에서는 하향링크에서 사용자 용량 증가를 위하여 통계적 다중화에 기반한 RFH-OFDMA(Random Frequency Hopping-Orthogonal Frequency Division Multiple Access) 방식을 제안한다. 사용자 용량은 한 셀에서 주어진 기본 데이터 전송률로 데이터 전송이 가능한 최대 사용자의 수를 의미한다. 본 논문에서는 제안된 통계적 다중화 기반의 RFH-OFDMA 방식의 하향링크 사용자 용량과 기존 FH-OFDMA 방식에서의 하향링크 사용자 용량을 비교한다. 사용자 용량은 부반송파 개수와 인접 셀 간섭에 의하여 제한되며 수신 SINR이 가장 열악한 환경에서의 시스템 용량을 상호 비교하기 위하여 사용자는 모두 셀 경계에 있다고 가정하고 인접 셀 간섭은 최대 값을 갖는다고 가정한다. 시뮬레이션 결과를 통하여, 사용자의 채널 활성도가 0.1, 수신단에서 요구되는 Eb/IO가 6dB, 3-sector 안테나가 사용된 경우에 제안된 RFH-OFDMA 방식이 262명을 수용한 반면에 기존의 FH-OfDMA방식의 경우 51명의 사용자를 수용할 수 있음을 보여준다.