• The Plant Pathology Journal
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• 제39권6호
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• pp.566-574
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• 2023

The aim of this study was to investigate the regulation of lantipeptide production in Streptomyces globisporus SP6C4, which produces the novel antifungal lantipeptides conprimycin and grisin, and to identify the role of cytochrome P450 (P450) in tis regulation. To investigate the regulation of lantipeptide production, we created gene deletion mutants, including ΔP450, ΔtsrD, ΔlanM, ΔP450ΔtsrD, and ΔP450ΔlanM. These mutants were characterized in terms of their morphology, sporulation, attachment, and antifungal activity against Fusarium oxysporum. The gene deletion mutants showed distinct characteristics compared to the wild-type strain. Among them, the ΔP450ΔlanM double mutant exhibited a recovery of antifungal activity against F. oxysporum, indicating that P450 plays a significant role in regulating lantipeptide production in S. globisporus SP6C4. Our findings highlight the significant role of P450 in the regulation of lantipeptide production and morphological processes in S. globisporus. The results suggest a potential link between P450-mediated metabolic pathways and the regulation of growth and secondary metabolism in SP6C4, thereby highlighting P450 as a putative target for the development of new antifungal agents.

• 대한기계학회논문집A
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• 제21권8호
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• pp.1250-1258
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• 1997

This paper reports on the development of a new foot for a quadrupedal jointed-leg type walking robot. The foot has 2 toes, one at the front and the other at the rear side, for stable landing on uneven ground by point contact. The toes can move up and down independantly, guided by double-wishbone shaped parallel links which enable the lower leg to rotate with respect to a remote center on the ground surface. The motion of each toe is damped by a hydropneumatic shock absorber integrated in the foot in order to absorb the dynamic landing shock. Furthermore, the new foot can reduce the maximum hip joint drive torque by shortening the moment arm length between the hip joint and the landing force vector on the ground. Intensive experiments were carried out in this study by using a one-leg walking model to investigate the soft landing performance of the foot which could be hardly offered by conventional robot feet such as a flat plate with a gimbal type ankle joint. And it was confirmed that the hip joint torque of the leg walking on the flat surface could be reduced remarkably by using the new foot.

• Asian Pacific Journal of Cancer Prevention
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• 제17권3호
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• pp.993-1001
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• 2016

Type 2 diabetes mellitus patients are at increased risk of many forms of malignancies, especially of the pancreas, colon and hepatocellular cancer. Unfortunately, little is known of the possible interaction between antidiabetic drugs and anticancer agents. The present study investigates the influence of metformin (MET) and sitagliptin (SITA) on the in vitro anticancer activity of the microtubule depolymerization inhibitor agent epothilone A (EpoA). Hepatocellular liver carcinoma cell line (HepG2) viability and apoptosis were determined by the MTT test and by double staining with PO-PRO-1 and 7-aminoactinomycin D, respectively, after treatment with EpoA, metformin or sitagliptin. The levels of nuclear factor NF-${\kappa}B$ and p53 were evaluated in the presence and absence of inhibitors. While EpoA and MET inhibited HepG2 cell proliferation, SITA did not. EpoA and SITA induced higher p53 levels than MET. All tested drugs increased the level of NF-${\kappa}B$. Only MET enhanced the proapoptotic effect of EpoA. The EpoA+MET combination evoked the highest cytotoxic effect on HepG2 cells and led to apoptosis independent of p53, decreasing the level of NF-${\kappa}B$. These findings support the link between NF-${\kappa}B$ and p53 in the modulation of apoptotic effects in HepG2 cells treated by EpoA. Our studies indicate that the combination of EpoA and MET applied in subtoxic doses has a stronger cytotoxic effect on liver cancer cells than each of the compounds alone. The therapeutic advantages of the combination of EpoA with MET may be valuable in the treatment of patients with diabetes mellitus type 2 (T2DM) and liver cancer.

• 한국정보통신학회논문지
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• 제13권4호
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• pp.629-635
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• 2009

본 논문에서는 하나의 국부 발진기를 갖는 FSK 이중통신 방식의 원격제어 무선 전송부를 설계 제작한다. 전 이중 방식의 FSK 양방향 동시통신 회로에서는 양방향 동시 통신을 위한 송수신 주파수를 설정하고, 반 이중방식에서는 송수신 신호를 발생하는 절체형 발진기 회로를 설계한다. 양 FSK 이중통신 방식의 원격제어 무선 전송부는 채널주파수간 간섭을 배제하기 위한 채널 사용 검지 및 자동 채널 설정 회로를 설계 구현하였으며, 400MHz 대역에서 50kHz 채널 간격을 갖는 위상동기 회로 구성의 Colpitz 형 국부발진주파수 회로와 10mW 이내의 소형 소출력 특성을 갖는다. 전 이중 방식의 송수신 주파수는 21.4MHz IF주파수의 2배 주파수인 42.8MHz주파수 간격으로 설계 구현하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제13권3호
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• pp.867-872
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• 2012

Background: $FOXP3^+$ regulatory T cells (Tregs) inhibit effector T cell functions and are implicated in tumour progression. However, together with microvessel density (MVD) they remain controversial prognostic predictors for renal cell carcinoma (RCC), and potential associations have yet to be determined. The objective of this study was to determine the prognostic significance of Tregs and MVD and their potential relationship in RCCs. Design: Paraffin-embedded tissues from 62 RCC patients were analysed using immunohistochemistry to detect $FOXP3^+$ lymphocytes, and double immunohistochemistry to detect different microvessel types in the tumour interior, rim and normal kidney tissue, and their correlation with clinicopathological characteristics. Survival analysis was also performed. Results: The presence of $FOXP3^+$ cells in the tumour interior or the rim showed no correlation with death from RCC and other pathological characteristics. Negative correlations were noted between the immature MVD in the tumour interior or the rim and tumour size, tumour stage and overall survival; however, there was no correlation with the nuclear grade or pathological type. A positive correlation between $FOXP3^+$ Tregs and immature MVD (r=0.363, P=0.014) and mature MVD (r=0.383, P=0.009) was confirmed in the tumour interior. However, there was no correlation between $FOXP3^+$ Tregs and mature MVD (r=0.281, P=0.076) or immature MVD (r=0.064, P=0.692) in the tumour rim. Conclusions: In this study, a positive correlation between the presence of $FOXP3^+$ Tregs and immature and mature MVD in RCC was confirmed, which suggests a link between suppression of immunity, tumour angiogenesis and poor prognosis.

• 한국항행학회논문지
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• 제14권5호
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• pp.625-631
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• 2010

본 논문에서는 대표적인 측정치 기반형 보정정보인 RTCM v2 18/19 메시지와 보정치 기반형 보정정보인 RTCM v2 20/21 메시지, 그리고 저속통신매체용으로 제안된 바 있는 SNUR 메시지에 대하여 난수신 환경에서의 강전성 비교를 수행하였다. 일시적은 데이터 손실 경우와 단절 인지 후 재접속의 경우를 난수신 환경으로 가정하여, 각각 2초와 7초 동안 모든 메시지가 지연된 경우에 대하여 이중 차분된 측정치 비교를 통해 성능을 평가하였다. 수행 결과 7초 통신 단절의 경우 SNUR방식이 기존 RTCM 메시지에 비해 오차의 양을 30~60% 줄일 수 있음을 확인하였다. 뿐만 아니라, RTCM 메시지의 경우 7초의 지연시 L1반파장 이상의 오차가 발생하여 기추정된 미지정수를 사용할 수 없는 경우가 발생하였으나, SNUR 메시지 적용시 오차가 모두 1/4 파장이내에 포함됨을 확인하였다.

• 한국통신학회논문지
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• 제33권3B호
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• pp.112-122
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• 2008

블루투스 시스템은 피코넷을 기반으로 네트워크를 형성하여 데이터를 전송한다. 하나의 피코넷에는 하나의 마스터 장치와 최대 일곱 개의 슬레이브 장치로 구성될 수 있다. 폴링기법을 사용한 피코넷의 마스터 장치는 잡 스케줄러를 수행하여 피코넷의 모든 슬레이브 장치들에게 데이터 전송 기회를 제공한다. 최대 데이터 전송률은 두개의 블루투스 장치로 이뤄진 피코넷에서 ACL 링크의 DH5형태의 패킷을 사용할 경우이다(최대 데이터 전송률: 723.2 kb/s). 그러나, 한 개의 마스터 장치와 두 개의 슬레이브 장치로 구성된 피코넷의 경우, 마스터 장치는 접속된 모든 슬레이브 장치에게 동등한 데이터 전송률을 제공해줘야 하기 때문에, 데이터 전송률은 절반(361.6 kb/s)으로 줄어든다. 그리고, 스캐터넷에서의 데이터 전송률은 더욱 낮아(최대 전송률: 302.2 kb/s) 지는 단점이 있다. 본 논문에서는 여러개의 피코넷으로 이루어진 스캐터넷에서의 낮은 데이터 전송률을 해결하기 위하여 "더블피코(DoublePico)"라 불리는 새로운 애드혹 네트워크 형태를 제안한다. 또한, 본 논문에서 제안된 더블피코는 블루투스를 이용한 애드혹 네트워크에서 높은 데이터 전송률(최대 전송률: 457.57 kb/s)을 제공한다.

• 수산경영론집
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• 제17권1호
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• pp.77-106
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• 1986

In the field of fisheries, there is at the apex Central Federation of Fishery Cooperatives, established under the Fishery Cooperatives Law(1962), It is a multipurpose organization with a membership of 105 cooperatives, 87 regional cooperatives, 15 business-type cooperatives and 3 manufactures' cooperatives. Accordingly, this thesis examines the marketing of fishery cooperatives in Korea, and in particular considers the marketing channel strategy of fisheries products. No company can perform by itself all the activities involved in the production and distribution of its products and services to its final markets. It must work with other firms to get the job done. Thus marketing channel firms of the fisheries products include primarily the fishery cooperatives, the licensed In the field of fisheries, there is at the apex Central Federation of Fishery Cooperatives, established under the Fishery Cooperatives Law (1962). It is a multipurpose organization with a membership of 105 cooperatives, 87 regional cooperatives, 15 business-type cooperatives and 3 manufactures' cooperatives. Accordingly, this thesis examines the marketing of fishery cooperatives in Korea, and in particular considers the marketing channel strategy of fisheries products. No company can perform by itself all the activities involved in the production and distribution of its products and services to its final markets. It must work with other firms to get the job done. Thus marketing channel firms of the fisheries products include primarily the fishery cooperatives, the licensed dealers and the merchant middlemen. The goal of marketing is in matching of segments of supply and demand. Every producer seeks to the link the marketing channel firms that will help it accomplish its objective best. This thesis tries to attempt to improve the present Korean Fishery Cooperatives marketing activities. The purpose of the operation of fishery cooperatives is to guarantee the profits of fisherman as well as the interests of general consumers by eliminating the inordinate profits of middlemen and by narrowing other market margins. Fishery cooperatives marketing activity functions forming a self-helf organization for economic protection of producers themselves, and acting as a market reformational institution through its transaction by group. The following are the characteristics of fishery cooperatives marketing. \circled1 Fishery cooperatives is organized with an economic factor and a personnel factor. \circled2 Fishery cooperatives is non-profit organization. \circled3 The members of fishery cooperatives is independent constitution of economy, but they are closely connected with the cooperative. \circled4 Fishery cooperatives is a mutual aid organization. The objective of an efficient marketing strategy may be well described by the common saying provides the right product at the right time, the right place, and the right price. But it is quite true that the Korean Fishermen's Cooperative can be said to owe its development to the successful implementation of the marketing system. The use of the marketing system has resulted in the following marketing strategy. 1. The direct marketing system. \circled1 The cooperation between the fishery cooperatives and the other cooperative through the collection and delivery center. \circled2 The selling between the fishery cooperatives and the large scale retailers through the process industry. 2. The vertical marketing system. \circled1The fishermen's cooperative to be nominated by wholesaler in the terminal market. \circled2 Contracted vertical marketing system. \circled3 Abolition of selling by double auction in the landing and the terminal market. 3. The physical distribution system. \circled1 The need for adoption of cold chain system to connect production directly to consumption. \circled2 The need for more expansion of landing markets and terminal market facilities. Solutions to the problems of the Korean fishery are made possible through effective functioning of cooperative marketing activities of fishery products. The marketing concept of fishermen's cooperative lies in the satisfaction of consumer needs. According to the marketing concept fishermen's cooperative should try to satisfy customer's needs through a coodinated set of activities that allows the organization to achieve its goal. Providing satisfaction to customers is the major trust of the marketing concept. To do this, a business must find out what will satisfy customers. With this information the cooperative sells to the greatest possible number of customers through the most efficient sales and marketing channels. Economic rationality of fishermen's cooperative marketing lies in reduction of marketing cost and elimination of intermediate institutions. Cooperative marketing and direct marketing are both indispensable marketing factors for a new cooperative organization among the manu ways. The cooperation between the fishermen's cooperative and the others cooperative, and vertical marketing system are the most necessary ones. Propulsion of cooperative marketing system could not be successful without the support of the marketing instituion's help. Consequently, successful cooperative marketing ought to lead to the necessity not only for the improvement of marketing organization, but for the application of a new marketing concept in the fishermen's cooperative.