• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.4C
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• pp.333-341
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• 2002

This article is written to make a foundation for effective radio network engineering by enabling the accurate traffic assumption between Base Station (BTS : Base Station Transceiver Subsystem) md Repeater through the scientific and systematic analysis of mobile traffic dealt within CDMA Base Station. Among these, Repeater, having direct physical connection with BTS, simply does the remote relay function but the volume of the traffic flowed into the repeater is not accountable. The total BTS traffic is the sum of traffic dealt by the BTS and multiple Repeaters. In this article, we tried traffic analysis of this kind by adopting RTD (Round Trip Delay) which is specially designed to measure distribution of the distance between the Base Station and the Mobile station by differentiating the traffic dealt by BTS from traffic dealt by Repeaters. The fact that the connection between mobile station and BTS via Repeater (which is located remotely) yields far more delay than the direct connection between mobile station and BTS is the clue of this article. Based on this fact, Time Delay equipment was put at the receiving side of the Repeater to add certain amount of delay to the traffic to BTS and the result showed that the 99.78% of the traffic can be identified.

• Korean Business Review
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• v.11
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• pp.83-100
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• 1998

The objective of our study is to build a theoretical framework for the examination of impacts of cross-functional integration upon new product development performance(NPDP). For this purpose, we have concentrated our efforts on systematically delving into how cross-functional integration factors affect upon the interdepartmental cooperation and upon the NPDP while dividing those critical integration factors into the structural and the infra-structural ones. We have selected interdepartmental job-rotation, consigning of papers, and cross-functional teem meeting as structural cross-functional integration factors. On the other hand, we have chosen Quality Functional Deployment(QFD), Concurrent Engineering(CE), and Evaluation and Reward Systems as those infra-structural cross-functional integration factors. After identifying those integration factors, we have carefully searched the relationship between those integration factors and those cooperation variables (interdepartmental common goal, interdepartmental interactions, and common sharing of ideas and informations) to look into how they affect upon the NPDP. Among cross-functional integration and NPDP related studies, our study is the first to show systematically how strongly infra-structural integration factors affect upon the achievement of interdepartmental cooperation and the improvement of NPDP. Considering the limitation of our resources and time available for this research, we have limited our study to building only a theoretical framework for future empirical studies to look into how cross-functional integration variables are related with NPDP.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.4
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• pp.387-392
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• 2015

A method for measuring and analyzing the $NO_x$ in ships is described in $NO_x$ Technical Code 2008. The analysis device, as required by the Code, has been to use a Chemi-luminescence detection method or Heated Chemi-luminescence detection. on the other hand, selective catalytic reduction using $NH_3$ as a reducing agent has an interference effect on the analyzer, and causes measurement error. In this study, the Chemi-luminescence detection method was examined according to how it affects the concentration of $O_2$, CO, $SO_2$, $NH_3$. Fourier transform infrared spectrometry analysis equipment and measurement methods were compared. In order to confirm the effect of the physical interference of the measuring device, it was confirmed by decomposing a measuring device. Consequently, white precipitate and moisture were generated inside the chemiluminescence detection system and I found that affecting interference. The influence of interference highlights the need to consider the minimized $NO_x$ measurement method.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.4
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• pp.443-448
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• 2015

A swirl type mixer was developed to improve the flow mixing performance of a marine selective catalytic reduction system. In this study, the swirl type mixer and a multi-staged swirl type mixer, in which the angle of the vanes at each stage is controllable were considered to provide the optimal region of angles for the mixers. The effects of the vane angles in both mixers on the uniformity index and pressure drop were investigated using a computational fluid dynamics simulation. In the swirl type mixer, the optimal conditions for the flow mixing performance were observed at vane angles from 30 to 60 degrees when vane angles could be adjusted between 10 to 80 degrees, however, the pressure drop increased continually with increasing vane angle of the mixer. On the other hand, control of the individual staged angles of the multi-staged mixer showed that it is possible to keep enhancing flow mixing performance while reducing the pressure drop.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.9
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• pp.799-804
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• 2016

Broadband powerline communication (BPLC) uses distribution lines as a medium for achieving effective bidirectional data communication along with electric current flow. As the material characteristics of power lines are not good at the communication channel, the development of power line communication (PLC) systems for internet, voice, and data services requires measurement-based models of the transfer characteristics of the network suitable for performance analysis by simulation. In this paper, an analytic model describing a complex transfer function is presented to obtain the attenuation and path parameters for a multipath power line model. The calculated results demonstrated frequency-selective fading in multipath channels and signal attenuation with frequency, and were in good agreement with the experimental results. Inductive coupling units are used as couplers for coupling the signal to the power line to avoid physical connections to the distribution line. The inductance of the ferrite core, which depends on the frequency, determines the cut-off frequency of the inductive coupler. Coupling loss can be minimized by increasing the number of windings around the coupler. Coupling efficiency was improved by more than 6 dB with three windings compared to the results obtained with one winding.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.9
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• pp.836-841
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• 2016

An indoor positioning system using Wi-Fi is essential to produce a radio map that combines the indoor space of two or more dimensions, the information of node positions, and etc. in processing for constructing the radio map, the measurement of the received signal strength indicator(RSSI) and the confirmation of node placement information counsume substantial time. Especially, when the installed wireless environment is changed or a new space is created, easy installation of the node and fast indoor radio mapping are needed to provide indoor location-based services. In this paper, to reduce the time consumption, we propose an algorithm to distinguish the straight and curve lines of a corridor section by RSSI visualization and Sobel filter-based edge detection that enable accurate node deployment and space analysis using cable-type Wi-Fi node installed at a 3 m interval. Because the cable type Wi-Fi is connected by a same power line, it has an advantage that the installation order of nodes at regular intervals could be confirmed accurately. To be able to analyze specific sections in space based on this advantage, the distribution of the signal was confirmed and analyzed by Sobel filter based edge detection and total RSSI distribution(TRD) computation through a visualization process based on the measured RSSI. As a result to compare the raw data with the performance of the proposed algorithm, the signal intensity of proposed algorithm is improved by 13.73 % in the curve section. Besides, the characteristics of the straight and the curve line were enhanced as the signal intensity of the straight line decreased by an average of 34.16 %.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.28 no.4
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• pp.393-413
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• 2017

This study will explore the possibility of applying process innovation as a public library for business innovation. In order to do this, the study defines the concept of process innovation through the literature review. According to survey and focus group interviews with librarians working for public libraries, this study will organize work done at libraries into the following categories: acquisition, resource management, user management, user services, programs, volunteer management, marketing, library computerization system, facility management, general affairs and statistical management. In addition, through face-to-face surveys with librarians working for public libraries it is confirmed that there are issues within acquisition, user management, and applied process innovation. In response to these issues a new process has been developed. Using this new approach, book contract procedure and requests for book related work could be improved and optimized. In the user management section, the study analyzes the requirements and subscription procedures for members through a website survey of 30 public libraries in the United States and then provides an improved system through process analysis of the membership process of Korean public libraries. It is expected that the new system will contribute to improvements in user satisfaction as well as improvements in library workflow.

• Tunnel and Underground Space
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• v.21 no.1
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• pp.11-19
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• 2011

Geothermal energy is believed to be an important source among the renewable energy sources to provide the base load electricity. Although there has been a drastic increase in the use of geothermal heat pump in Korea, there is no geothermal power plant in operation in Korea. Fortunately, the first EGS (Enhanced Geothermal System) Project in Korea has started in Dec 2010. This five year project is divided into two stages; two years for exploration and drilling of 3 km depth to confirm the minimum target temperature of 100 degrees, and another three years composed drilling 5 km doublet, hydraulic stimulation of geothermal reservoir with expected temperature of 180 degrees (40 kg/s) and construction of MW geothermal power plant in the surface. This EGS project would be a landmark effort that invited a consortium of industry, research institutes and university with expertises in the fields of geology, hydrogeology, geophysics, geomechanics and plant engineering.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.115-115
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• 2015

국내 물관련 건설 및 설비 업체를 대상으로 하는 설문조사 및 인터뷰 결과 국내 물 관련 기업들의 해외진출 시 가장 큰 애로사항은 해외경험 직원의 부족으로 나타났다. 해외사업 확대를 위해서는 고부가가치 업무를 수행할 수 있는 고급기술자와 관리 인력의 양성이 시급하며, 특히 건설사업관리(CM, PM)나 설계/엔지니어링을 담당할 고급 기술 인력의 양성이 필요한 것으로 조사되었다. 경쟁력있는 글로벌 기술 관리 인력의 양성은 정부의 주도하에 기존의 물 관련 기관의 교육프로그램 통합 운영 및 내실있는 전문 수자원 대학원 운영 등 장기적인 정책적인 지원이 필수적이다. 또한 현재 해외 물시장 정보 수집의 활성화를 위하여 국토교통부, K-water, 해외건설협회 등이 연계한 물 산업 전담 정보시스템 구축과 중점 수출대상국 선정 후 대상국에 해외지부 운영 등이 필요할 것이다. 금융지원과 관련하여 해외건설 금융지원 강화를 위한 글로벌 인프라펀드 조성, 해외건설 보증한도 확대 등이 필요하며, 'EDCF 등 공적금융의 물산업 지원 확대 등 재정지원을 위한 정부의 적극적인 역할 역시 중요하다. 해외 물시장 진출을 위해서는 국내 물기업들의 역량을 결집하는 것이 필요하며, 이를 위해서는 효율적인 공공 민간 협의체의 설립 및 운영이 이루어져야 한다. 전 세계적으로 물 산업은 높은 공공성과 함께토탈 솔루션 역량이 중시되고 있으며, 이런 시장환경에 부응하여 네덜란드, 독일 등 물산업 수출 강국은 자국의 물관련 분야를 결집하는 워터 파트너십을 설립하여 국제사회에서 위상과 세계시장 점유율을 동시에 높여가고 있는 실정이다. 이들 국가 워터파트너십의 공통적인 설립 목적은 궁극적으로 자국 물 관련 산업, 국가 브랜드 및 이니셔티브와 관련되는 국제협력, 정책 분야 등의 결집이다. 다시 말해서 정부가 주축이 되어 관 산 학 연 기관간의 정보제공, 협력 등을 도모하고 있으며 이 네트워크의 구심점 역할 및 촉진은 자국의 워터파트너십이 맡고 있는 것이다. 해외 물 시장 확대를 도모하고 있는 우리나라도 국가차원의 장기적이고 지속적인 해외 물산업 네트워크 구축을 위해서는 정부-공기업-민간기업 등의 협력을 토대로 한 Korea Water Partnership을 조속히 설립하는 것이 필요하다. 이를 위해서는 국토부, 환경부 등 물 관련 부처는 물론 글로벌 네트워크를 구축하고 있는 외교부, 무역협회 등 유관기관의 정보 연계 및 협조 체계 역시 필요하다. 정부부처 차원의 조직은 국제 정치 아젠다(agenda)에 중대한 영향을 줄 수 있으며, 경쟁적 우위와 유사기관 간의 정보와 네트워킹의 공유를 보다 원활하게 할 수 있기 때문이다. Korea Water Partnership에서는 한국이 보유하고 있는 선진 수자원기술 및 경험을 해외에 소개하고, 정부 및 민간 기업들의 물 산업 수출역량을 적극적으로 피력할 수 있는 기회를 마련하며, 국제사회에서 물 강국으로서 한국의 위상을 높일 수 있는 홍보 마케팅 창구로서의 역할을 기대할 수 있을 것이다.

• Ecology and Resilient Infrastructure
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• v.8 no.2
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• pp.88-96
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• 2021

In surface image velocimetry, a wide area of a river is photographed at an angle to measure its velocity, inevitably causing image distortion. Although a distorted image can be corrected into an orthogonal image by using 2D projective coordinate transformation and considering reference points on the same plane as the water surface, this method is limited by the uncertainty of changes in the water level in the event of a flood. Therefore, in this study, we developed a tilt image correction technique that corrects distortions in oblique images without resetting the reference points while coping with changes in the water level using the geometric relationship between the coordinates of the reference points set at a high position the camera, and the vertical distance between the water surface and the camera. Furthermore, we developed a distortion correction method to verify the corrected image, wherein we conducted a full-scale river experiment to verify the reference point transformation equation and measure the surface velocity. Based on the verification results, the proposed tilt image correction method was found to be over 97% accurate, whereas the experiment result of the surface velocity differed by approximately 4% as compared to the results calculated using the proposed method, thereby indicating high accuracy. Application of the proposed method to an image-based fixed automatic discharge measurement system can improve the accuracy of discharge measurement in the event of a flood when the water level changes rapidly.