• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.7B
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• pp.695-705
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• 2002

In this paper, we propose a simple open loop transmit diversity (TD) scheme for the wideband code division multiple access (W-CDMA) systems in Rician multipath fading channels such as rural area or satellite channels where line-of-sight (LOS) paths are in presence. The proposed scheme does not require any pre-processing of transmit data, resulting in simpler structure as compared to conventional closed loop transmit adaptive array (TxAA) and open loop space-time transmit diversity (STTD). We analytically derive the probability density function of signal-to-noise ratio at the Rake receiver output and the uncoded bit error rate performance of the proposed scheme. Extensive simulation is Performed to verify the analytical performance of the proposed scheme under typical Rician multipath fading channel environments. Moreover, comparative results with the conventional TxAA and STTD are also provided. Simulation results show that the proposed scheme shows slightly better performance than the conventional open loop STTD under the channels with very weak LOS components, however, it significantly outperforms the STTD under the channels with dominant LOS components, and achieves a close performance of ideal closed loop TxAA.

• Journal of Digital Contents Society
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• v.19 no.7
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• pp.1271-1279
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• 2018

The telecommunication industry, which has traditionally formed its own market area, has also been affected by the after shock of the digitalization triggered by computer communications. In the telecommunications industry, digitalization or digital services refers to network functional virtualization supported by software defined networks. The digitalization of the telecom industry is changing rapidly, and the participants are not limited to the traditional equipment suppliers and service providers in established market, but includes virtually all social entities. To understand this new change, focusing on whether the traditional equipment suppliers that have traditionally played a pivotal role in the center of change will continue its role in this new era of digitalization or not, and how they are progressing toward end-to-end digital services, the goal of digitalization, will lead us to the good understanding of ongoing digitalization.

• The Journal of the Korea Contents Association
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• v.13 no.7
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• pp.110-119
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• 2013

Since the early 20th century photo based art and effort to creative experiment, to pursue the essence of creation to escape from stereotypes between form and media, expression and technology, has been continued persistently. Photomontage was born as an artistic attempt for the new representation. Basically photomontage is configured to visually emphasize the message as a work to produce new meaning by combining the various images that are intentionally selected. The photomontage as a visual art, dialectic of text and image that is to pursue a new format to be out the concept already existing, have been developed, the concept is similar to the modern multiple art. The value of photo montage is to explore of the photo, not limited to describe or reproduce as a deformation, the new possibilities for creative expression and the experience of the day-to-day operation for the implementation of the scheme.

• The Journal of the Korea Contents Association
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• v.16 no.12
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• pp.677-694
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• 2016

This study examines the differences of support exchange and factors impacting on the support exchange between the elderly and their grown-up children in 2011. Socioeconomic variables are introduced as independent variables. Emotional, physical, and financial support exchanges are used as dependent variables. Descriptive statistics and multiple analysis of variance are used for the statistical analysis. Findings of this study are as follows: First, the support exchanges between the grown-up children living with parents and elderly parents are significantly varied by the socioeconomic factors. Second, the support exchanges between the children not living with their parents and the elderly parents are significantly varied by the socioeconomic factors. A majority of the elderly are suffering from financial difficulties and they do not receive appropriate supports from their grown-up children. On the other hand, it turned out that the elderly parents are highly contributable to provide the emotional support for their family members, and provide the emotional support to their grown-up children.

• Journal of Korean Society for Geospatial Information Science
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• v.14 no.1 s.35
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• pp.29-36
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• 2006

In the process of location selection, it is assumed that transformer substation socially recognized as a dangerous facility require especially more rigorous and resonable process. This paper implements suitability analysis for optimum location selection of transformer substation in southern Gyeonggi province using AHP(Analytic Hierarchy Process) and spatial analysis of GIS in terms of safety, national land use, economical efficiency and environment preservation. To do this, necessary data from 1/5,000 digital map are extracted a s raster format for suitability analysis and a field investigation also was done. In the procedure of site selection, three candidate zones with 1.5km radius were selected for the whole research area and then through field survey low transformer sites were selected from candidate zones. In the last the appropriateness of selected sites was evaluated. The results of the suitability analysis showed that the first candidate site satisfied the location condition best and other candidate sites generally showed good location condition.

• Journal of the Korean Chemical Society
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• v.21 no.6
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• pp.395-403
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• 1977

Significant structure theory was applied to some liquid mixture systems ranging from simple monatomic molecule systems to polyatomic molecule systems, and the activity coefficients ${\gamma}$ of the liquid mixture systems were calculated over whole mole fractions using the following thermodynamic relation $RTln_{{\gamma}i} = (\frac{{\partial A}^E}{{\partial N}_i})_{T,V,N_i} $ where $A^E$ represents the excess Helmholtz free energy, and $N_i$ is the number of molecules of component i. The activity coefficients of the solutions such as monatomic molecule systems (Ar-Kr, Kr-Xe) and diatomic molecule systems $(Ar-O_2,\;N_2-CO)$ and $CH_4-Kr$ systems whose components have similar shapes for intermolecular potential curves were calculated successfully only with the ${\delta}E_s$, correction parameter for energy $E_s$, for mixture systems. For other systems such as $Ar-N_2,\;O_2-N_2\;and\;CH_4-C_3H_8$ whose components have dissimilar intermolecular potential curve shapes an additional correction parameters ${\delta}$V and even one more parameter ${\delta}$n were necessary [see Eqs.(10)∼(12)].

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.8 no.6
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• pp.600-613
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• 1997

The implementation of a BTS(Base station Transceiver) for WLL system using W-CDMA(Wideband-Code Division Multiple Access) method is presented in this paper. It consists of three boards; receiver, transmitter and RF controller. Some RF parameters are considered and simulated by the RF simulation S/W using commercial and customized components specifications. The implemented transceiver of 5 MHz RF channel bandwidth satisfies the system requirements of a transceiver such as dynamic range, sensitivity in the receiver and spurious emission suppression in the transmitter. At the receiver, the experimental measurement showed 2.86 dB of NF and 60 dB above of dynamic range in AGC(Automatic Gain Control) locking. At the transmitter, the -49.46 dBc of spurious emission suppression is attained when the output power of the transmitter is 34.3 dBm. These results are good enough to meet to standard performance specifications.

• Tuberculosis and Respiratory Diseases
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• v.63 no.2
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• pp.173-177
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• 2007

Tuberculosis remains as a major public health problem worldwide. In addition to classic pulmonary tuberculosis, tuberculosis may sometimes present atypically. In the case of atypical tuberculosis, the unusual sites and properties that mimic other diseases can lead to a misdiagnosis and therapeutic delay. Abdominal and pharyngeal tuberculosis are uncommon extrapulmonary manifestations of tuberculosis. To the best of our knowledge, a combination of abdominal and pharyngeal tuberculosis with endobronchial tuberculosis has not been reported. We report a case of concurrent abdominal and pharyngeal tuberculosis in a patient with chronic endobronchial tuberculosis mimicking a metastatic malignancy on computed tomography and FDG-PET.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.10
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• pp.1987-1993
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• 2016

The core value of the college of Interdisciplinary & Creative Studies is rely on the supporting system which can develop the learners' practical 'performing' competency. For aiming this, educational process of university constitutes the competencies which can be expected at the local field and develop the competency-oriented extracurricular & its operating system. Defining the creative convergent talent, as 'collaborative creative convergent one, bricoleur' and categorizes core competency named as TX competency. T competency contains humanities and the professionals of each major field needed. X competency consists of creative problem solving, convergent thinking ability, self-oriented learning ability and cooperative leadership. Developing extracurriculum & its operating system learners can be exposured the systemic learning and managing process. They can develop their potential abilities and can accumulate a proper mileage at their learning achievement. This research can be expected as a model of competency-based extracurriculum and its operating system which can develop learners' multiple competency overcoming the limit scope of curriculum.

• JOURNAL OF ELECTRICAL WORLD
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• s.351
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• pp.89-94
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• 2006

에너지 해외의존도 97%, 무역의존도 70%인대한민국. 우리는하루220만배럴, 연간8억배럴이상을소비한다. 부존자원이 극도로 빈약한 우리나라가 나아가야 할 길은자명하다. 에너지 자원을 거의수입해 의존하다보니 이를고부가화 해 내수에 돌리면서 최우선으로 수출을 통해 온나라가 먹고 살고 있다해도 과언이아니다. 해외 에너지자원을 안정적으로 확보하는 것이 바로 국가경쟁력의 근원이 되는것은 어제오늘의 일이 아니다. 고유가 파고를 헤쳐나가야 한다는 절박한현실에서안정적인 에너지자원확보를 위한 정부의 해외자원분야 정책 및 민관전략이 올들어 의욕적으로 전개되고 있다. 우선정부는 자원개발 업무를 강화하기 위해 현재1과1팀의 자원개발조직을 보강하 고유전개발팀을 신설하는 등 모두3개팀으로 늘린다. 나아가 해외 자원확보에주력 산업 동반진출도 착착진행하고 있다. 국내 자원 개발 기업과 에너지관련기업, 해외진출기관등 14곳으로 구성된 ‘에너지산업해외진출협의회’도 최근 출범시켰다. 유전을탐사하거나 개발하는데 개인들도간접투자할수있는 ‘유전개발펀드’도 7월에 첫 선을 보인다. 약2000억원규모의이 시범펀드 도입 등을 통해 자원개발을 가속화,2013년까지원유-가스자주개발률을18%(원유15%, 가스30%)까지 끌어 올릴 계획이며 여기에16조원 신규투자가 소요 될 것으로보고있다. 이같은 일련의 공격적인 움직임은 단순히 돈을 주고 자원을 사오는 기존방식을 앞으로는과감히탈피,자원부국이 원하는 산업인프라등을 수주해제 공한뒤 그 대가로자원을 확보하는 총체적 자원확보전략에 무게를두겠다는 의지를 담고 있어 고무적이다. 여기에 다원유 등 수입원자재 가격이 급등세를 보이고있는 가운데 우리나라의 해외 자원개발사업이 활기를 띠고있다.석유공사는 민간기업들과 함께 지난해에만 예멘2곳 등 전세계 5개국9곳의 석유 및 천연가스 광구계약을체결, 올들어 최근참여사들과 함께 주주간계약 서명식을 갖고본격적인 사업을 추진 중이다. 광업진흥공사역시 SK네트웍스와제휴, 최근 전체 매장량이650만t으로 추정되는 중국 후난성의 아연광 탐사권을 획득, 합작 사설립계약을 체결한 것으로 알려지고 있다. 민간기업들도 해외자원분야진출이 활발하다. 기업들의 해외 자원개발을 위한 투자규모도 늘어 올해38개 해외 자원개발기업이 32개국 211개 사업에 모두31억달러를 투자할 계획인것으로 나타났다. 이에본지는 올해 들어서도 고유가의 지속으로 속증하고 있는에너지수입동향과 해외 자원 개발의 현실과 문제점, 개선방향, 나아가 최근 안전적인 자원확보를 위한 동향을 진단해본다.