• Journal of Technology Innovation
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• v.22 no.3
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• pp.101-133
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• 2014

Climate change and low-carbon consumer movement is demanding proper response around the world while rising oil price increases consumers' needs for green car. As a preliminary study to establish an industrial platform for green car and bring out corporate strategies, this article aims to propose an academic research framework by using various methodologies including conceptual/mathematical modeling, system dynamics, and ABM from different angles. First, an analysis framework for the industrial platform was introduced to analyze green car cases, required elements were proposed, and econometrics was applied to build a basic model related to green platform (two-sided market). Also, to analyze from a dynamic perspective, a system dynamics model was applied to green car environment to build a system dynamics analysis model that is applicable to particular green car industry analysis. Lastly, an agent based model was used to study the way to activate the hybrid car market in Korea from individual consumers' perspective. Based on the result, vehicle policies that are either being enforced or planned to be enforced in the Korean HEV market can be analyzed.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.10
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• pp.1089-1097
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• 2002

In this paper, the novel shipboard Active Phased Array Antenna(APAA) system for maritime mobile satellite communications is introduced. The antenna uses novel technologies like wide range hybrid tracking, single antenna elements with both of Rx and Tx, asymmetrical array structure, interference isolation between Rx and Tx, and error correction method from frequency scan effect. The antenna has single aperture for both of Rx and Tx with 32 $\times$ 4 two-dimensional array. The antenna has two beams. Its frequencies are 7.25 ~ 7.75 GHz for Rx and 7.9 ~ 8.4 GHz for Tx. The antenna gains are 35.4 dBi for Rx and 35.7 dBi for Tx, those are 54 % of efficiency. The electrically steering ranges are $\pm$35$^{\circ}$ of elevation direction and $\pm$4$^{\circ}$ of azimuth direction. The mechanical control ranges at hybrid tracking capability are continuous 360$^{\circ}$ of azimuth direction and $\pm$10$^{\circ}$ of elevation direction. The antenna has 2.2$^{\circ}$ of 3 dB beamwidth, -14 dB of sidelobe level, and 21 dB of cross-pol suppression. The antenna performance was measured by near field measurement set. Its system performance was tested on the ship motion simulator and with the satellite transponder simulator. The test result showed that its tracking error was within -3 dB from its peak gain under motion condition. The antenna system was tested by real modulated Direct Broadcasting Satellite(DBS) signals to check its communication processing function.

• Journal of Information Management
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• v.41 no.4
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• pp.227-249
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• 2010

Scholarly information has increased tremendously according to the development of IT, especially the Internet. However, simultaneously, people have to spend more time and exert more effort because of information overload. There have been many research efforts in the field of expert systems, data mining, and information retrieval, concerning a system that recommends user-expected information items through presumption. Recently, the hybrid system combining a content-based recommendation system and collaborative filtering or combining recommendation systems in other domains has been developed. In this paper we resolved the problem of the current recommendation system and suggested a new system combining collaborative filtering and Naive Bayes Classification. In this way, we resolved the over-specialization problem through collaborative filtering and lack of assessment information or recommendation of new contents through Naive Bayes Classification. For verification, we applied the new model in NDSL's paper service of KISTI, especially papers from journals about Sitology and Electronics, and witnessed high satisfaction from 4 experimental participants.

• Clean Technology
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• v.27 no.2
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• pp.124-131
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• 2021

As declarations of carbon neutrality are spreading throughout the world, much research is being conducted on biodegradable polymers. In this study, nanocellulose, which comprises the largest amount of natural polymer currently available in the world, was proposed as a substitute for non-biodegradable polymers. We chose to modify the surface functional group of crystalline nanocellulose using glycidoxypropyl trimethoxysilane (GPTMS), which is a silane coupling agent, and the product was then used to form a film with low density polyethylene (LDPE). We then conducted measurements using a Fourier transform infrared spectrophotometer (FT-IR) in addition to measuring hydrophilic/lipophilicity of the surface functional group modification of crystalline nitrocellulose as well as that of a polymer composite using the hybrid nanocellulose (H-NC). For compatibility with petroleum-based polymers, the best tensile strength and transparency was found when the H-NC was reacted at pH 14 and 1 wt% compared with LDPE. From the test results, we found that it is possible to modify the surface functional groups of nanocellulose using a silane coupling agent. In addition, the high compatibility of nanocellulose with petroleum-based polymers is expected to help in reaching carbon neutrality by reducing the use of fossil fuels.

• Journal of the Korean Electrochemical Society
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• v.18 no.2
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• pp.45-50
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• 2015

In the present work, to increase the chemical stability of the lithium-ion-conducting ceramic electrolyte ($Li_{1+x+y}Al_xTi_{2-x}Si_yP_{3-y}O_{12}$, LATP) in the strong alkaline solution, the surface of LATP was modified by the nitridation process. The surface and structural properties of nitride LATP solid electrolyte were characterized by X-ray diffraction, X-ray photoelectron spectrometer and scanning electron microscopy and ac-impedance spectroscopy, which were correlated to the chemical stability and electrochemical performance of LATP. The nitrided LATP immersed in the alkaline solution for 30 days exhibits the enhanced chemical stability than the pristine LATP. Moreover, a rechargeable hybrid Li-air battery constructed with the nitrided LATP solid electrolyte shows considerably reduced discharge-charge voltage gaps (enhanced the round-trip efficiency) in comparison to the cell constructed with pristine LATP, which indicate that the surface nitridation process can be the efficient way to improve the chemical stability of solid electrolyte in alkaline media.

• Journal of Intelligence and Information Systems
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• v.23 no.4
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• pp.77-110
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• 2017

Recently, the diversification and individualization of consumption patterns through the web and mobile devices based on the Internet have been rapid. As this happens, the efficient operation of the offline store, which is a traditional distribution channel, has become more important. In order to raise both the sales and profits of stores, stores need to supply and sell the most attractive products to consumers in a timely manner. However, there is a lack of research on which SKUs, out of many products, can increase sales probability and reduce inventory costs. In particular, if a company sells products through multiple in-store stores across multiple locations, it would be helpful to increase sales and profitability of stores if SKUs appealing to customers are recommended. In this study, the recommender system (recommender system such as collaborative filtering and hybrid filtering), which has been used for personalization recommendation, is suggested by SKU recommendation method of a store unit of a distribution company that handles a homogeneous brand through a plurality of sales stores by country and region. We calculated the similarity of each store by using the purchase data of each store's handling items, filtering the collaboration according to the sales history of each store by each SKU, and finally recommending the individual SKU to the store. In addition, the store is classified into four clusters through PCA (Principal Component Analysis) and cluster analysis (Clustering) using the store profile data. The recommendation system is implemented by the hybrid filtering method that applies the collaborative filtering in each cluster and measured the performance of both methods based on actual sales data. Most of the existing recommendation systems have been studied by recommending items such as movies and music to the users. In practice, industrial applications have also become popular. In the meantime, there has been little research on recommending SKUs for each store by applying these recommendation systems, which have been mainly dealt with in the field of personalization services, to the store units of distributors handling similar brands. If the recommendation method of the existing recommendation methodology was 'the individual field', this study expanded the scope of the store beyond the individual domain through a plurality of sales stores by country and region and dealt with the store unit of the distribution company handling the same brand SKU while suggesting a recommendation method. In addition, if the existing recommendation system is limited to online, it is recommended to apply the data mining technique to develop an algorithm suitable for expanding to the store area rather than expanding the utilization range offline and analyzing based on the existing individual. The significance of the results of this study is that the personalization recommendation algorithm is applied to a plurality of sales outlets handling the same brand. A meaningful result is derived and a concrete methodology that can be constructed and used as a system for actual companies is proposed. It is also meaningful that this is the first attempt to expand the research area of the academic field related to the existing recommendation system, which was focused on the personalization domain, to a sales store of a company handling the same brand. From 05 to 03 in 2014, the number of stores' sales volume of the top 100 SKUs are limited to 52 SKUs by collaborative filtering and the hybrid filtering method SKU recommended. We compared the performance of the two recommendation methods by totaling the sales results. The reason for comparing the two recommendation methods is that the recommendation method of this study is defined as the reference model in which offline collaborative filtering is applied to demonstrate higher performance than the existing recommendation method. The results of this model are compared with the Hybrid filtering method, which is a model that reflects the characteristics of the offline store view. The proposed method showed a higher performance than the existing recommendation method. The proposed method was proved by using actual sales data of large Korean apparel companies. In this study, we propose a method to extend the recommendation system of the individual level to the group level and to efficiently approach it. In addition to the theoretical framework, which is of great value.

• Journal of Chest Surgery
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• v.43 no.6
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• pp.729-733
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• 2010

Endovascular treatment of the aortic aneurysm with a stent graft is rapidly evolving. We describe here a case of hybrid TEVAR (thoracic endovascular aortic repair) in which the stent grafts were placed in the aortic arch after debranching of the arch vessels. The patient had undergone ascending aorta replacement for acute type I aortic dissection 2.5 years earlier. The aneurysmal change of the distal dissection progressed with time. A provisional bypass surgery from the ascending aorta to the innominate artery and left carotid artery was performed and then stent grafts were inserted via an antegrade route that covered the whole aortic arch and proximal descending thoracic aorta.

• The Journal of Korean Academy of Prosthodontics
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• v.56 no.4
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• pp.368-374
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• 2018

In this case, the patient was restored with gold Hader bar mandibular implant overdenture using two implants about 10 years ago, and the retentive force was lost due to severe wear of the bar due to 3.5 years use. The overdenture was repaired using a Locator attachment, but the male part was completely worn after 6.5 years use. Finally, we used a hybrid telescopic double crown with a friction pin to fabricate a new implant overdenture, which was observed for 2 years and showed excellent prognosis. So, we describe the cause of failure of each attachment (Gold Hader bar, Locator) in two implant overdentures and report on the advantages and disadvantages of double crown implant overdenture and the conditions for success.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.7
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• pp.589-594
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• 2014

Recently, higher capacity and energy density of lithium ion batteries are increasingly demanded for enhancing their performance in view of the rise in the commercial distribution of electric and hybrid vehicles. Computational analysis of a porous structure of vanadium pentoxide cathode was performed, employing a phase field model. The incipient model was designed as a spherical structure with cylindrical-shaped pores. Modifying the diameters and lengths of the pore cylinder and the number of pores, we considered different conditions for the porous vanadium pentoxide cathodes for analyzing their effect on the amount of lithium ion intercalated to them. Subsequently, we optimized the porous structure to contain the largest amount of intercalated lithium ion during discharge.

• The Inventors News
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• no.53
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• pp.1-16
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• 2006

'여성기업지원에 관한 법률' 개정 한 목소리/발행인 칼럼/'제4회 여성발명경진대회' 수준 높아졌다/심사착수 예정시기 직접 통지 서비스 실시/특허청.한국기계연구원, 업무협약체결/낙도어린이들에게 꿈과 희망 심어주는 초청 행사 가져/특허청 팀장 선발 방식 변화 통한 팀제 강화/디자인 권리화 지원사업 실시한다/'DMB 특허품과 지재권전략 세미나'/'2006 독일 국제발명품 전시회' 회원 4명 수상/고성능 하이브리드 보호복, 출원 증가/'이달의 기능 한국인' 박순복 씨 선정/모방상표, 더 이상 등록 받을 수 없다/국내제약업계, 유사브랜드 너무많아/'2006 여성 재활용 발명경진대회' 개최/순수 한방재료로 만든 헤어 클리닉 화제/발명자에게 편리한 특허제도 마련/차로 마시는 '허브 추출물'로 살충제 만들어/종이컵에도 웰빙 바람이 불고 있다/특허공보 통해 '나의 발명' 확인가능/지역특산품도 지리적 표시로 보호 받는다/한미약품,'비만치료제 특허권 분재' 연승/국내특허, 해외에서 신속하게 심사 처리/'스판덱스 특허소송'에서 일본업체 패소/아모레, 다국적 화장품회사 로레알에 승소/제7차 한국.유럽 특허청장 회담 개최/고부가가치 창출하는 단백질 의약품 개발 필요/한방 진료에도 변화의 새바람 분다/에너지 절감'기능성 유리' 출원 급증/역사 속의 발명품/하루 10분 발명교실/특허Q&A/세상을 밝히는 여성들의 발명 아이디어/'특허넷' 정부기관 최초 CMMI 레벨4인증 획득/'해외지재권 보호 가이드북' 제작배포하다/아이디어 착상 및 발명 기법/고정관념을 깨트려 블루오션을 장악하라/에반스의 증기제분기/50년 후엔 동물과도 대화할 수 있다/첩보용 도구 전달 '발명팀' 실제 존재/중소기업 위한'2006 특허유통 페스티벌' 개최/출원료.심사청구료 반환제도 도입, 시행/'지재권 e-러닝 콘텐츠' 전 세계특허청 교육 자료로 활용/대한변리사회, 미 특허법 세미나 개최/한국여성발명협회 회원사 발명품 가이드