• 경영과학
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• 제22권1호
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• pp.179-197
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• 2005

This study examines market acceptance for DMB service, one of the touted new business models in Korea's next-generation mobile communications service market, using adoption end diffusion of innovation as the theoretical framework. Market acceptance for DMB service was assessed by predicting the demand for the service using the Bass model, and the demand variability over time was then analyzed by integrating the innovation adoption model proposed by Rogers (2003). In our estimation of the Bass model, we derived the coefficient of innovation and coefficient of imitation, using actual diffusion data from the mobile telephone service market. The maximum number of subscribers was estimated based on the result of a survey on satellite DMB service. Furthermore, to test the difference in diffusion pattern between mobile phone service and satellite DMB service, we reorganized the demand data along the diffusion timeline according to Rogers' innovation adoption model, using the responses by survey subjects concerning their respective projected time of adoption. The comparison of the two demand prediction models revealed that diffusion for both took place forming a classical S-curve. Concerning variability in demand for DMB service, our findings, much in agreement with Rogers' view, indicated that demand was highly variable over time and depending on the adopter group. In distinguishing adopters into different groups by time of adoption of innovation, we found that income and lifestyle (opinion leadership, novelty seeking tendency and independent decision-making) were variables with measurable impact. Among the managerial variables, price of reception device, contents type, subscription fees were the variables resulting in statistically significant differences. This study, as an attempt to measure the market acceptance for satellite DMB service, a leading next-generation mobile communications service product, stands out from related studies in that it estimates the nature and level of acceptance for specific customer categories, using theories of innovation adoption and diffusion and based on the result of a survey conducted through one-to-one interviews. The authors of this paper believe that the theoretical framework elaborated in this study and its findings can be fruitfully reused in future attempts to predict demand for new mobile communications service products.

• 시스템엔지니어링학술지
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• 제7권2호
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• pp.7-11
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• 2011

A high-speed railway system represents a typical example of large-scale multi-disciplinary system, consisting of subsystems such as rolling-stock, electrical hardware, electronics, control, information, communication, civil technology etc. The system design and acquisition data of the large-scale system must be the subject under strict configuration control and management. Systems engineering technology development project for Korea next generation High-speed Electric Multiple Unit (HEMU) system in progress is a national large system development project that is not only a large-size and complex but also multi-disciplinary in nature. Therefore, all stakeholders must understand and share the functional and performance requirements of HEMU throughout its life-cycle phases. Also in the test and evaluation phase, all systems requirements must be verified. In 2011, the prototype train manufacturing will be completed. It will do test run on the commercial line and all systems requirements are verified until 2012. For the system verification, the test and evaluation process have to be established before the test trial run. Using a systems engineering tool, the system design database(SDD) with requirements traceability and development process management in the course of the development have to be established. This paper represents the test and evaluation process development based on the SEMP(Systems Engineering Management Plan) developed in the design stage. The test and evaluation process is refined and updated in comparison to the design stage one. The test and evaluation process consists of procedure, test and evaluation method and schedule. So through this process, it is defined that each systems requirements is verified on which test and about what time.

• International Journal of Oral Biology
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• 제45권3호
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• pp.134-142
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• 2020

Colon cancer is one of the most common malignant tumors, but there are still a few validated biomarkers of colon cancer. Exosome-mediated microRNAs (miRNAs) have been recognized as potential biomarkers in cancers, and miRNAs can regulate a variety of genes. Recently, Fusobacterium nucleatum was discovered in the tissues of human colon cancer patients. Its role in colon cancer was highlighted. F. nucleatum may contribute to the progression of colon cancer through the mechanism of exosome-mediated miRNAs transfer. However, the exosomal miRNAs regulation mechanism by F. nucleatum in colon cancer is not well known. Thus, we performed next-generation sequencing to investigate the overall pattern of exosomal miRNAs expression in the colon cancer cell culture supernatant. We have confirmed the alterations of various exosomal miRNAs. In addition, to investigate the function of exosomal miRNAs, a Kyoto Encyclopedia of Genes and Genomes analysis was performed on the target genes of changed miRNAs. Potential target genes were associated with a variety of signaling pathways, and one of these pathways was related to colorectal cancer. These findings suggested that F. nucleatum can alter exosomal miRNAs released from colorectal cancer cells. Furthermore, exosomal miRNAs altered by F. nucleatum could be potential biomarkers for the diagnosis and therapy of colon cancer.

• 정보처리학회논문지A
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• 제9A권3호
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• pp.317-326
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• 2002

도시 인구 집중과 이동 인구의 증가로 이동 통신 시스템은 90년대 이후 급격한 발전을 하고 있다. 그러나 현재 널리 사용되고 있는 2세대 이동 통신 시스템은 음성에만 치중하여 개발되었고 시장이 거의 포화상태에 이르렀다. 따라서 앞으로 다가올 UMTS와 같은 제 3세대 이동 통신 시스템에서는 무선 인터넷과 같은 본격적인 데이타 서비스를 위해 패킷 데이타 통신이 매우 중요한 부분으로 떠오르고 있다. 음성 서비스와는 달리 패킷 데이타 특성에 갖는 패킷 데이타 서비스를 제공하기 위해서 UMTS 시스템에서는 전송하기 전에 반드시 데이타를 버퍼에 저장해야 한다. 하지만 지금까지 패킷 데이타 서비스를 위한 버퍼가 어떻게 얼만큼 필요하고 트래픽에 따라 그 상태가 어떻게 변화하는지에 관한 연구는 거의 진행되어 있지 않다. 본 논문에서는 UMTS 시스템에서 BS (Base Station)에 놓이는 버퍼 상태가 어떻게 변화하는지 알아 보기 위해 버퍼 상태 분석을 위한 UMTS 시스템 모델을 구성하고 실험을 통해 그 결과를 관찰 분석한다. 그리고 버퍼 상태를 확률을 통해 수식적으로도 분석한다.

• Parasites, Hosts and Diseases
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• 제54권6호
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• pp.751-758
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• 2016

This study aimed at constructing a draft genome of the adult female worm Toxocara canis using next-generation sequencing (NGS) and de novo assembly, as well as to find new genes after annotation using functional genomics tools. Using an NGS machine, we produced DNA read data of T. canis. The de novo assembly of the read data was performed using SOAPdenovo. RNA read data were assembled using Trinity. Structural annotation, homology search, functional annotation, classification of protein domains, and KEGG pathway analysis were carried out. Besides them, recently developed tools such as MAKER, PASA, Evidence Modeler, and Blast2GO were used. The scaffold DNA was obtained, the N50 was 108,950 bp, and the overall length was 341,776,187 bp. The N50 of the transcriptome was 940 bp, and its length was 53,046,952 bp. The GC content of the entire genome was 39.3%. The total number of genes was 20,178, and the total number of protein sequences was 22,358. Of the 22,358 protein sequences, 4,992 were newly observed in T. canis. Following proteins previously unknown were found: E3 ubiquitin-protein ligase cbl-b and antigen T-cell receptor, zeta chain for T-cell and B-cell regulation; endoprotease bli-4 for cuticle metabolism; mucin 12Ea and polymorphic mucin variant C6/1/40r2.1 for mucin production; tropomodulin-family protein and ryanodine receptor calcium release channels for muscle movement. We were able to find new hypothetical polypeptides sequences unique to T. canis, and the findings of this study are capable of serving as a basis for extending our biological understanding of T. canis.

• 한국산학기술학회논문지
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• 제18권10호
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• pp.81-87
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• 2017

본 연구는 고속열차 시운전 시험과 이에 따른 주행동특성 고찰 및 개선에 관한 것이다. 고속열차 시운전 시험을 통한 선행 연구에서 도출한 요댐퍼 설치 방법에 따른 후미 진동 개선 방안을 실제 고속철도 차량의 시운전시에 적용하여 후미 진동 저감 효과가 있음을 확인하였다. 또한 전체 차량에 대한 진동저감 방안을 동역학 해석 소프트웨어를 사용하여 수치 해석적 방법으로 도출하였으며, 그 효과를 시운전 시험을 통하여 확인하였다. 개선된 설계안은 실제 2층 고속열차 객차에 적용되어 주행동특성 문제없이 시운전을 진행하였다. 차세대 고속열차 임계속도에 영향을 미치는 현가장치 파라미터들에 대한 민감도 분석을 수행하였으며, 임계속도에 크게 영향을 미치는 4개의 설계변수를 도출하였는데, 이는 1차 탄성조인트 열차진행 방향 강성, 2차 요댐퍼 시리즈 강성, 2차 횡댐퍼 댐핑계수, 차간 댐퍼 댐핑계수 순이었다. 이 설계변수에 대한 최적화를 통하여 임계속도를 23.3% 향상시키는 현가장치 파라미터를 제시하였으며, 이는 차세대 고속열차 상용화 모델의 설계에 이용될 수 있다.

• Journal of Communications and Networks
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• 제7권2호
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• pp.157-170
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• 2005

The combination of multiple antennas and multi-carrier code division multiple-access (MC-CDMA) is a strong candidate for the downlink of the next generation mobile communications. The study of such systems in scenarios that model real-life trans-missions is an additional step towards an optimized achievement. We consider a realistic MIMO channel with two or four transmit antennas and up to two receive antennas, and channel state information (CSI) mismatches. Depending on the mobile terminal (MT) class, its number of antennas or complexity allowed, different data-rates are proposed with turbo-coding and asymptotic spectral efficiencies from 1 to 4.5 bit/s/Hz, using three algorithms developed within the European IST-MATRICE project. These algorithms can be classified according to the degree of CSI at base-station (BS): i) Transmit space-frequency prefiltering based on constrained zero-forcing algorithm with complete CSI at BS; ii) transmit beamforming based on spatial correlation matrix estimation from partial CSI at BS; iii) orthogonal space-time block coding based on Alamouti scheme without CSI at BS. All presented schemes require a reasonable complexity at MT, and are compatible with a single-antenna receiver. A choice between these algorithms is proposed in order to significantly improve the performance of MC-CDMA and to cover the different environments considered for the next generation cellular systems. For beyond-3G, we propose prefiltering for indoor and pedestrian microcell environments, beamforming for suburban macrocells including high-speed train, and space-time coding for urban conditions with moderate to high speeds.

• 한국통신학회논문지
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• 제37C권11호
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• pp.1011-1019
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• 2012

본 논문에서는 차세대 전술이동통신체계에서의 무선 MSAP 메쉬망에서 효율적으로 인증키를 관리하고 전술이동 통신체계의 부하를 줄이는 새로운 혼합형 인증기법을 제안한다. 또한 각각의 MSAP와 TMFT가 인증받는 알고리즘이 다르므로 인증요청 받은 MSAP의 제어대(ACR)에서 EAP 패킷의 Code 부분을 확인하여 처리하는 방안도 제안한다. 기존의 방식에서 각 MSAP가 체계접속을 위해서는 중앙집중형 인증기법과 분산형 인증기법을 활용할 수 있는데 각각은 문제점을 안고 있다. 즉, 중앙집중형 인증기법은 MSAP의 빈번한 가입 및 탈퇴로 인한 과다한 지연 문제가 있고 분산형 인증기법은 인증에 필요한 정보를 사전에 공유해야 하는 문제점이 있다. 이러한 문제점을 보완하는 동시에 전술적인 환경에서 악의적인 MSAP의한 접속거부와 네트워크 보안성을 극대화하기 위해서는 보다 효과적인 인증기법이 요구된다. 따라서 본 논문에서는 미 인증된 MSAP가 EAP-TLS 기법을 기반으로 전술이동통신네트워크 진입시 초기 인증과 이웃 MSAP간의 상호인증 등 다양한 시나리오를 군의 특수한 환경에 맞추어 구체적으로 제시하고 성능평가를 통해 혼합형 인증기법이 군 전술환경에 효율적으로 적용될 수 있음을 보였다.

• 한국통신학회논문지
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• 제36권1B호
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• pp.60-70
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• 2011

IPTV는 2010년 초반 가입자가 200만 명을 넘어서는 등 빠른 성장세를 보이고 있다. 그러나 이러한 성장세의 지속 여부에 의문이 제기되고 있다. 이러한 의문은 IPTV 성장의 주요 기반에 서비스 자체의 경쟁력에 있느냐 하는 점과 2010년 들어 가입자 증가 속도가 둔화되고 있으며, 가입자 수의 증가에도 불구하고 IPTV 사업자들이 수익을 내지 못하고 있는 점 등 때문에 제기되었다. 이러한 현상은 현재의 IPTV 서비스가 시장에서 요구하는 적절한 서비스 위치를 확보하지 못하였기 때문에 발생한다. 본 연구는 이러한 문제점을 해결하기 위해, 케이블 TV 가입자들의 IPTV로의 전환 요인이 무엇인지를 밝혀내어 소비자들이 인식하고 있는 IPTV 만의 서비스 가치가 무엇인지를 분석한다. 그리고 이러한 전환 요인 중 모바일 IPTV 비즈니스 모델 구성시 반드시 고려해야 할 요인이 무엇인지를 분석한다. 또한 모바일 IPTV서비스로부터 소비자들이 획득하고자 하는 가치와 IPTV서비스 제공과 관련된 사업자 등이 제공하고자 하는 서비스 가치 간에 어떠한 차이가 있는지를 밝혀, 모바일 IPTV 서비스 제공시 소비자 가치에 부합되는 서비스를 제공하기 위한 전략적 요인들을 제시하고자 한다.

• Journal of Plant Biotechnology
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• 제43권3호
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• pp.311-316
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• 2016

The efficacy of plant breeding has been enhanced by application of molecular markers in population screening and selection. Pepper (Capsicum annuum L.) is a major staple crop that is economically important with worldwide distribution. It is valued for its spicy taste and medicinal effect. The aim of this study was to discover single nucleotide polymorphisms (SNPs), microsatellite markers information, and percentage sharing through orthologous analysis of pepper-specific pungency-related genes. Here, we report the results of transcriptome analysis and microsatellite markers for four pepper varieties that possess a pungency-related gene. Orthologous analyses was performed to identify species-specific pungency-related genes in pepper, Arabidopsis thaliana L., potato (Solanum tuberosum L.), and tomato (Solanum lycopersicum L.). Advancements in next-generation sequencing technologies enabled us to quickly and cost-effectively assemble and characterize genes to select molecular markers in various organisms, including pepper. We identified a total of 9762, 7302, 8596, and 6886 SNPs for the four pepper cultivars Blackcluster, Mandarine, Saengryeg 211, and Saengryeg 213, respectively. We used 454 GS-FLX pyrosequencing to identify microsatellite markers and tri-nucleotide repeats (54.4%), the most common repeats, followed by di-, hexa-, tetra-, and penta-nucleotide repeats. A total of 5156 (15.9%) pepper-specific pungency-related genes were discovered as a result of orthologous analysis.