• 한국전기전자재료학회논문지
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• 제27권4호
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• pp.250-256
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• 2014

The wind power generation is an eco-friendly clean energy that produces almost zero $CO_2$ emission, and has a good economic feasibility. As for the location, the installation of large turbines and construction of large-scale wind farm is easier on the offshore than on the land. In Korea, it is inevitable to generate offshore wind power through the offshore wind farm, and the radio interference of larger wind power generators and offshore wind power farm to broadcasting, communication and radars is becoming a core issue for constructing the offshore wind farm. In this study, the wind power generation status and rotor blade technology trend were presented, along with the technical trend of radar radio interference reduction relating to construction of the offshore wind farm.

• 펄프종이기술
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• 제42권3호
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• pp.67-73
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• 2010

Pine (Pinus densiflora) and aspen (Populus euramericana) wood meals were treated with ozone at various time schedule in acidic condition. The lignin contents and surface area of the ozone treated wood meals were determined and the enzymatic hydrolysis rate of ozonated wood meals was evaluated. The feasibility of enzymatic hydrolysis of the ozone treated wood meal was obviously influenced with the degree of delignification. After ozone treatment of wood meal for 10min, total pore volume were slightly increased in the surface of wood meal. When wood meals were treated with ozone longer than 10min, few change in the pore volume was observed. However, the area of over $50{\AA}$ of pore size is increased with ozonation time. As a conclusion, the rate of enzymatic hydrolysis of wood is more effective with the pore size distribution than the total pore volume.

• 방송공학회논문지
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• 제24권7호
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• pp.1266-1275
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• 2019

With increasing criminal rates and number of CCTVs, much attention has been paid to intelligent surveillance system on the horizon. Object detection and tracking algorithms have been developed to reduce false alarms and accurately help security agents immediately response to undesirable changes in video clips such as crimes and accidents. Many studies have proposed a variety of algorithms to improve accuracy of detecting and tracking objects outside tunnels. The proposed methods might not work well in a tunnel because of low illuminance significantly susceptible to tail and warning lights of driving vehicles. The detection performance has rarely been tested against the tunnel environment. This study investigated a feasibility of object detection and tracking in an actual tunnel environment by utilizing YOLOv3 and Kernelized Correlation Filter. We tested 40 actual video clips to differentiate pedestrians and motorcycles to evaluate the performance of our algorithm. The experimental results showed significant difference in detection between pedestrians and motorcycles without false positive rates. Our findings are expected to provide a stepping stone of developing efficient detection algorithms suitable for tunnel environment and encouraging other researchers to glean reliable tracking data for smarter and safer City.

• Wind and Structures
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• 제21권6호
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• pp.625-639
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• 2015

Monopiles have been most widely used for supporting offshore wind turbines (OWTs) in shallow water areas. However, multi-member lattice-type structures such as jackets and tripods are also considered good alternatives to monopile foundations for relatively deep water areas with depth ranging from 25-50 m owing to their technical and economic feasibility. Moreover, jacket structures have been popular in the oil and gas industry for a long time. However, several unsolved technical issues still persist in the utilization of multi-member lattice-type supporting structures for OWTs; these problems include pile-soil-interaction (PSI) effects, realization of dynamically stable designs to avoid resonances, and quick and safe installation in remote areas. In this study, the effects of PSI on the dynamic properties of bottom-fixed OWTs, including monopile-, tripod- and jacket-supported OWTs, were investigated intensively. The tower and substructure were modeled using conventional beam elements with added mass, and pile foundations were modeled with beam and nonlinear spring elements. The effects of PSI on the dynamic properties of the structure were evaluated using Monte Carlo simulation considering the load amplitude, scouring depth, and the uncertainties in soil properties.

• Structural Engineering and Mechanics
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• 제61권3호
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• pp.359-370
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• 2017

This study presents a particle swarm optimization algorithm integrated with weighted particle concept and improved fly-back technique. The rationale behind this integration is to utilize the affirmative properties of these new terms to improve the search capability of the standard particle swarm optimizer. Improved fly-back technique introduced in this study can be a proper alternative for widely used penalty functions to handle existing constraints. This technique emphasizes the role of the weighted particle on escaping from trapping into local optimum(s) by utilizing a recursive procedure. On the other hand, it guaranties the feasibility of the final solution by rejecting infeasible solutions throughout the optimization process. Additionally, in contrast with penalty method, the improved fly-back technique does not contain any adjustable terms, thus it does not inflict any extra ad hoc parameters to the main optimizer algorithm. The improved fly-back approach, as independent unit, can easily be integrated with other optimizers to handle the constraints. Consequently, to evaluate the performance of the proposed method on solving the truss weight minimization problems with discrete variables, several benchmark examples taken from the technical literature are examined using the presented method. The results obtained are comparatively reported through proper graphs and tables. Based on the results acquired in this study, it can be stated that the proposed method (integrated particle swarm optimizer, iPSO) is competitive with other metaheuristic algorithms in solving this class of truss optimization problems.

• Nuclear Engineering and Technology
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• 제49권2호
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• pp.295-305
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• 2017

This paper reviews current status of the unified approach known as integrated safety assessment (ISA), as well as the associated SCAIS (simulation codes system for ISA) computer platform. These constitute a proposal, which is the result of collaborative action among the Nuclear Safety Council (CSN), University of Madrid (UPM), and NFQ Solutions S.L, aiming to allow independent regulatory verification of industry quantitative risk assessments. The content elaborates on discussions of the classical treatment of time in conventional probabilistic safety assessment (PSA) sequences and states important conclusions that can be used to avoid systematic and unacceptable underestimation of the failure exceedance frequencies. The unified ISA method meets this challenge by coupling deterministic and probabilistic mutual influences. The feasibility of the approach is illustrated with some examples of its application to a real size plant.

• Asian Pacific Journal of Cancer Prevention
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• 제15권13호
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• pp.5111-5116
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• 2014

Computed Tomography Colonography (CTC) is a medical imaging technology used in identifying polyps and colon cancer masses in the large intestine. The technique has evolved a great deal since its invention and has become a routine diagnostic procedure in Western countries due to its non invasiveness and ease of use. The objective of our study was to explore the possibility of CTC application in Indian hospitals. This paper gives an overview of the procedure and its commercial viability. The explanation begins with the domain aspects from gastroenterologist perspective, the new way of thinking in polyp classification, the technical components of CTC procedure, and how engineering solutions have helped clinicians in solving the complexities involved in colon diagnosis. The colon cancer statistics in India and the results of single institution study we carried out with retrospective data is explained. By considering the increasing number of patients developing colon malignancies, the practicality of CTC in Indian hospitals is discussed. This paper does not reveal any technical aspects (algorithms) of engineering solutions implemented in CTC.

• 한국실천공학교육학회논문지
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• 제2권2호
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• pp.113-119
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• 2010

본 연구의 목적은 공공부문 기술교원들의 능력향상을 위한 체계적인 연구를 수행하여 변화하는 교육환경 및 패러다임의 변화에 따른 교육시장의 변화에 능동적으로 대처하고 현장감 있고 내실 있는 기술교육을 실시할 수 있도록 기술교원의 능력향상을 위한 프로그램 개발의 기초를 마련하는데 있다. 특히 기술교육 분야에 종사하는 교원은 빠르게 발전하는 산업현장의 신기술에 대하여 동향을 잘 파악하고 있어야 할 뿐 아니라 새로운 기술과 지식을 습득할 수 있는 능력 또한 겸비하여야 한다. 본 연구에서는 기술교원의 능력에 대한 사전조사를 실시하여 타당성을 검토하고 현재의 능력개발 과정을 파악하며 조사 결과를 바탕으로 각 분야별로 능력향상을 위하여 필요한 요소를 도출하여 이에 부합하는 교육과정을 운영하는데 기초 자료로 사용하고자 한다.

• 한국전자파학회논문지
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• 제26권6호
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• pp.581-588
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• 2015

본 논문에서는 함정의 RCS(Radar Cross Section) 기준치 설정은 함정의 생존성, 기술적 건조 가능성, 운용성 등 여러가지 측면이 고려되어 결정될 수 있다. 본 연구는 수상함의 RCS 기준치 및 설계 목표치를 설정하기 위하여 수상함에 위협이 되는 대함유도탄, 연안레이다, 항공기 등의 기본 성능을 조사하고, 조사결과를 토대로 현재의 국내 기술수준에서 가능한 RCS 목표치/기준치 설정을 위한 절차를 제시하였다. RCS 기준은 가급적 낮게 설정하는 것이 생존성 측면에서 좋겠지만, 함정의 고유 기능에 대한 영향, 기술적인 한계, 비용 등을 감안하지 않을 수 없기 때문에, 이 연구에서는 구체적인 숫자의 제시보다는 기준에 필요한 요소를 분석하고, 생존성을 보장할 수 있는 RCS 범위를 제시함으로써 기준치 설정 절차를 제시하였다.

• KEPCO Journal on Electric Power and Energy
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• 제2권2호
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• pp.317-325
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• 2016

In recent years, the U.S, Japan, Europe and other developed countries are strategically developing technologies in order to prepare for paradigm shift affecting the electric power industry in a preemptive way. In particular, a chance for new business models and innovation in the electric power industry would rapidly increase with convergence of various technologies including Information and communication technologies. This study gathered up the theories and methodologies, and sorted out emerging technologies for the electric power industry with those theories. In order to find the emerging technologies, first, we identified the possible key issues of the electric power industry in the future using four mining techniques such as STEEP. Second, we drew agenda related with each key issue. Third, we organized candidates of the emerging technologies for solving the agenda and set the priority after evaluating the possibility of technical innovation and business. Finally, we selected the top fourteen of emerging technologies and assessed their feasibility. This study has a methodological significance because the emerging technologies were developed with a market-oriented approach rather than technical-push one that has been primarily used in another studies. The results of this study are able to be used in establishment of technology policy and R&D planning in the electric power industry.