• 무역학회지
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• 제43권2호
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• pp.47-67
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• 2018

본 연구는 13개 선진국과 15개 개발도상국을 대상으로 국가별 거시적 사회·경제 요인들이 해외직접투자의 유입에 미치는 영향을 파악하고, 국가 경제성장의 질적 수준 및 발전단계에 따른 차이를 살펴보았다. 해외직접투자는 국제 생산의 효율성을 최적화 시킬 수 있는 곳으로 이동하는 국제장기자본이라고 볼 수 있다. 따라서 해외직접투자의 유입에는 기업의 내부 결정 요소 외 외부 요건인 국가별 투자 환경도 영향을 줄 것이다. 지난 30년간 국가별 거시적 사회·경제변수를 활용하여 고정효과 패널 회귀분석을 실시한 결과, 선진국과 개발도상국에 유입되는 투자의 동기와 유형이 다르게 나타났다. 선진국의 경우 국내총생산, 소비지출과 재정지출이 가장 큰 영향을 주는 것으로 나타나 시장추구형 수평적 투자의 특성을 보였다. 반면, 개발도상국으로는 노동보상과 인적자본이 가장 큰 영향을 주는 것으로 나타나 효율성추구형 수직적 투자의 특성을 보였다.

• 경영정보학연구
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• 제21권2호
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• pp.69-89
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• 2019

최근 소비자들 사이에서 사용하지 않거나 적게 쓰는 자원을 다른 사람과 공유하는 공유경제에 대한 관심이 증대되고 있다. 본 연구에서는 공유경제의 대표 영역인 공유숙박 서비스를 중심으로 공유경제의 성공요인을 살펴보고자 한다. 공유경제와 숙박업 관련 선행연구와 이론을 바탕으로 공유숙박 서비스에서 중요한 세 가지 성공요인(경제성, 편리성, 신뢰성)을 선정하였다. 공유숙박 플랫폼인 Airbnb의 1,673개 숙박업체를 대상으로 경제성(숙박비, 청소비, 환불제도의 엄격성), 편리성(가용한 편의시설의 개수, 호스트 가능 언어 수), 신뢰성(고객 요구에 대한 응답률/응답시간, 슈퍼호스트 여부) 관련 요인들이 고객 만족도에 미치는 영향을 로지스틱 회귀분석을 통해 분석하였다. 연구결과 경제성에서는 환불제도의 유연함, 편리성에서는 가용할 편의시설의 개수, 신뢰성에서는 고객 요구에 대한 응답률과 플랫폼에서 제공하는 신뢰성의 지표인 슈퍼호스트 여부가 공유숙박 성공에 긍정적 영향을 미치는 것으로 밝혀졌다. 본 연구는 공유숙박 서비스의 성공을 위해 어떠한 요인을 중점적으로 고려하여 비즈니스 모델을 수립해야 하는지에 대한 방향성을 공유숙박 참여자에게 제시했다는 점에서 연구의 시사점이 있다.

• Journal of Microbiology and Biotechnology
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• 제18권4호
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• pp.799-804
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• 2008

Retrovirus tropism can be restricted by host cell factors such as Fv1, TRIM5${\alpha}$, and LvI that inhibit infection by targeting the incoming viral capsid. The Fv1 gene inhibits murine leukemia virus infection in mice, but the precise mechanism of Fv1-mediated restriction is poorly understood. Our previous studies had demonstrated that Fv1-mediated viral tropism can be determined within the capsid protein at position 114. To study the interaction between Fv1 and CA, we introduced amino acid substitution and deletion at this site in the N-tropic AKV capsid gene. The mutated two-LTR proviral DNAs were introduced into SC-1 cells by transfection. After transfection, cell supernatants collected from transfected cells were tested for host range susceptibility. The result indicated that substitution of amino acids did not alter tropism, but the deletion of 114His produced a virus with unusual tropism. The novel phenotype produced here failed to replicate in Fv1-expressing cells. This mutant virus showing such an extreme restriction pattern would be useful for studying the mechanism of Fv1-mediated restriction.

• Tuberculosis and Respiratory Diseases
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• 제74권6호
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• pp.269-273
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• 2013

Mucormycosis is a rare fungal disease that holds a fatal opportunistic fungal infection in diabetes mellitus, hematological malignancy, and immunocompromised host. Isolated pulmonary mucormycosis is extremely rare. Optimal therapy is a combined medical-surgical approach and a management of the patient's underlying disease. Herein, we report a case-study of isolated pulmonary mucormycosis which was being presented as multiple lung nodules in a patient with no underlying risk factors. Considering that the patient had poor pulmonary functions, we treated him with only antifungal agent rather than a combined medical-surgical approach. After treatment with antifungal agent for six months, the nodules of pulmonary mucormycosis were improved with the prominent reductions of size on the computed tomography.

• Asian Pacific Journal of Cancer Prevention
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• 제16권5호
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• pp.1919-1924
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• 2015

Polymorphisms in the region of the interleukin IL-28 gene on chromosome 19 have been related with clearance of hepatitis C virus (HCV), a major human pathogen responsible for chronic hepatitis, cirrhosis and hepatocellular carcinoma. About 3% of the world's population is infected with HCV. The long-term response to therapy is influenced by many host and viral factors, and recent evidence has indicated that some host genetic polymorphisms related to IL-28 are the most powerful predictors of virological response in patients with HCV. This study assessed frequency of the IL-28 polymorphism (rs8099917) in 50 patients (39 men and 11 women) with chronic hepatitis C using ZNA probe real time PCR new method. All patients were tested for genotype of HCV and the HCV viral load. In parallel, the levels of SGOT, SGPT and ALK enzymes were assessed. Treatment using Peg-interferon alpha with ribavirin was conducted for patients and subsequently samples were collected to detect any change in viral load or liver enzyme rates. The overall frequency of the TT allele is 74%, TG allele 20% and GG allele 6% and the percent of patients who had T allele was 84%. Clear reduction in viral load and liver enzymes was reported in patients with the T allele. Especially for genotype 1 which is relatively resistant to treatment, these alleles may have a role in this decline. In conclusion, we showed that IL-28 polymorphism rs8099917 strongly predicts virological response in HCV infection and that real-time PCR with Zip nucleic acid probes is a sensitive, specific and rapid detection method for detection of SNPs which will be essential for monitoring patients undergoing antiviral therapy.

• 전자공학회논문지S
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• 제35S권2호
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• pp.58-69
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• 1998

A contrp; suste, fpr SCARA robot is designed for implememting a robust dynamic control algorithm. this study forcuses on the use of DSPs in the design of joint controllers and interfaces in between the host cotroller and four joint controllers and in between the joint controllers and four servo drives. The mechanical body of SCARA robot and the servo drives are selected from the commercially available ones. The four joint controllers, assigned to each joint one by one, are combined into a common system through a mother board hardwarewise and through the global memeory softwarewise. The mother board is designed to connect joint controllers onto the board through the slots adopting PC/104 bus structures. And, the global memory stores the common data which can be shared by joint controllers and the host computer directly, which virtually combines the whole system into one. To demonstrate the performance and efficienty of the sytem, a robust inverse dynamic algorithm is proposed and implemented for a faster and more precise control. The robust inverse dynamic algorithm is basically derived from an inverse dynamci algorithm and a PID compensator. Based upon the derived dynamic equitions of SCARA robot, the inverse dynamic algorithm is intitially implemented within 0.3 msec of the control cycle in this system. The algoithm is found to be not accurate enough for the high speed and precision tasks due to inherent modelling errors and time-varying factors. Therefore, a variable PID algorithm is combined with the inverse dynamic algorithm to support robustness of control performance. Experimental datfor the proposed algorithm are presented and compared with the result obtained from PID and inverse dynamic algorithm.

• 통상정보연구
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• 제19권3호
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• pp.63-82
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• 2017

본 연구는 중국 캐시미어 민영기업의 해외진출에 관한 장벽요인을 부패, 정치적 리스크, 시장의 변동성, 문화적 차이, 그리고 기업의 자원부존도 측면에서 탐색하는 것이다. 현존하는 실무적 배경을 조사하기 위하여 내몽고에 위치하고 있는 후허하오터(呼和浩特), 바오터우(包頭), 오르도스(鄂爾多斯)에서 캐시미어 해외수출입 업무를 담당하고 있는 민영기업을 대상으로 조사를 실시하였다. 해외 현지국의 부패 및 정치적 리스크는 중국의 해외진출전략에 유의미한 영향을 미치지 않는 것으로 나타났으며 해외 현지국의 시장변동성은 기업의 성과에 부정적인 영향을 미치는 것으로 나타났다. 문화적인 차이는 비즈니스 성과에 부정적인 영향을 미치고 민영기업의 자원부존은 해외진출전략의 비즈니스 성과에 긍정적인 효과가 있는 것으로 나타났다. 마지막으로 본 연구의 토론에서 중국 민영기업의 해외진출전략의 장애를 극복하기 위한 중국 정부정책 및 산업생태계에 대한 실무적 시사점을 기술하였다.

• IMMUNE NETWORK
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• 제9권5호
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• pp.192-202
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• 2009

Background: Little information is available the role of Nitric Oxide (NO) in host defenses during human tuberculosis (TB) infection. We investigated the modulating factor(s) affecting NO synthase (iNOS) induction in human macrophages. Methods: Both iNOS mRNA and protein that regulate the growth of mycobacteria were determined using reverase transcriptase-polymerase chain reaction and western blot analysis. The upstream signaling pathways were further investigated using iNOS specific inhibitors. Results: Here we show that combined treatment with 1,25-dihydroxyvitamin D3 (1,25-D3) and Interferon (IFN)-${\gamma}$ synergistically enhanced NO synthesis and iNOS expression induced by Mycobacterium tuberculosis (MTB) or by its purified protein derivatives in human monocyte-derived macrophages. Both the nuclear factor-${\kappa}B$ and MEK1-ERK1/2 pathways were indispensable in the induction of iNOS expression, as shown in toll like receptor 2 stimulation. Further, the combined treatment with 1,25-D3 and IFN-${\gamma}$ was more potent than either agent alone in the inhibition of intracellular MTB growth. Notably, this enhanced effect was not explained by increased expression of cathelicidin, a known antimycobacterial effector of 1,25-D3. Conclusion: These data support a key role of NO in host defenses against TB and identify novel modulating factors for iNOS induction in human macrophages.

• 한국멀티미디어학회논문지
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• 제8권1호
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• pp.71-78
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• 2005

802.11b 표준 무선 랜 기반의 인프라스트럭처 네트워크에서 PDA를 무선 단말기로 사용하여 멀티미디어 데이터 전송 성능을 평가하였다. PDA는 주로 멀티미디어 데이터와 같은 대용량 데이터를 수신하는 용도로 사용된다. 그러나 이동 호스트인 PDA가 고정 호스트인 PC와 멀티미디어 데이터를 전송하는 과정에서 PC로부터 데이터를 수신하는 시간이 송신시간에 비해 항상 53% 이상 더 소요된다 본 논문에서는 데이터 전송 시 PDA수신시간의 지연에 영향을 미치는 요소들에 대한 성능평가를 수행하였다. 수신과정에서 파일 액세스 시간이 송신과정보다 4.11배까지 더 걸리고, 수신자 윈도우 크기의 변동(686바이트∼32,581바이트)이 심하기 때문에 PDA 수신시간이 길어진다. 수신지연을 개선하기 위해 응용계층에서 내부패킷 간격을 주지 않고 즉시 전송하고, TCP 수신버퍼의 크기를 늘리는 것이 효과적이다

• Asian-Australasian Journal of Animal Sciences
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• 제25권2호
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• pp.278-285
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• 2012

Poultry products are an important source of Salmonella enterica. An effective way to reduce food poisoning due to Salmonella would be to breed chickens more resistant to infection. Unfortunately host responses to Salmonella are complex with many factors involved. To learn more about responses to Salmonella in young chickens of 2 wk old, a cDNA Microarray containing 13,319 probes was performed to compare gene expression profiles between two chicken groups under control and Salmonella infected conditions. Newly hatched chickens were orally infected with S. enterica serovar Enteritidis. Since the intestine is one of the important barriers the bacteria encounter after oral inoculation, intestine gene expression was investigated at 2 wk old. There were 588 differentially expressed genes detected, of which 276 were known genes, and of the total number 266 were up-regulated and 322 were down-regulated. Differences in gene expression between the two chicken groups were found in control as well as Salmonella infected conditions indicating a difference in the intestine development between the two chicken groups which might be linked to the difference in Salmonella susceptibility. The differential expressions of 4 genes were confirmed by quantitative real-time PCR and the results indicated that the expression changes of these genes were generally consistent with the results of GeneChips. The findings in this study have lead to the identification of novel genes and possible cellular pathways, which are host dependent.