• Title/Summary/Keyword: 효율성 향상

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Effectiveness of an Environment-friendly Fumigator for Microorganisms that Can Cause Biological Damage to Records in Japan, Malaysia, and Oman (일본, 말레이시아, 오만의 기록물에서 분리한 유해미생물에 대한 친환경 기록물 소독장비 효과검증)

  • Kim, Min Ji;Lee, Eon Sook;Choi, Young Nam;Choi, Young Sin
    • Journal of Korean Society of Archives and Records Management
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    • v.15 no.2
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    • pp.165-179
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    • 2015
  • Archives have historical and academic values. That is why the study of preservation conditions and the environment for the effective management of various records progress. However, materials such as paper and adhesives will inevitably cause biological damages. These damages spread into the inner side of archives, which would make it impossible to recover. For example, archival records from Malaysia and Oman are easily exposed to biological damage because of these countries' hot and humid climate. As such, once records are damaged, disinfection operations are customary in these areas. Methyl bromide (MeBr) and ethylene oxide (EtO) were used in the disinfection process as they showed good insecticidal effect. However their antibacterial effect are negligible. As such, the need for an environmental-friendly fumigator was evident. An environmental-friendly fumigator is designed to improve storage stability. Such equipment is expected to contribute to prevention of damages to cultural heritages through its use of vaporization technology, maintenance of a disinfection space (chamber), and self-generation of nitrogen.

Performance Analysis of Adaptive Channel Estimation Scheme in V2V Environments (V2V 환경에서 적응적 채널 추정 기법에 대한 성능 분석)

  • Lee, Jihye;Moon, Sangmi;Kwon, Soonho;Chu, Myeonghun;Bae, Sara;Kim, Hanjong;Kim, Cheolsung;Kim, Daejin;Hwang, Intae
    • Journal of the Institute of Electronics and Information Engineers
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    • v.54 no.8
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    • pp.26-33
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    • 2017
  • Vehicle communication can facilitate efficient coordination among vehicles on the road and enable future vehicular applications such as vehicle safety enhancement, infotainment, or even autonomous driving. In the $3^{rd}$ Generation Partnership Project (3GPP), many studies focus on long term evolution (LTE)-based vehicle communication. Because vehicle speed is high enough to cause severe channel distortion in vehicle-to-vehicle (V2V) environments. We can utilize channel estimation methods to approach a reliable vehicle communication systems. Conventional channel estimation schemes can be categorized as least-squares (LS), decision-directed channel estimation (DDCE), spectral temporal averaging (STA), and smoothing methods. In this study, we propose a smart channel estimation scheme in LTE-based V2V environments. The channel estimation scheme, based on an LTE uplink system, uses a demodulation reference signal (DMRS) as the pilot symbol. Unlike conventional channel estimation schemes, we propose an adaptive smoothing channel estimation scheme (ASCE) using quadratic smoothing (QS) of the pilot symbols, which estimates a channel with greater accuracy and adaptively estimates channels in data symbols. In simulation results, the proposed ASCE scheme shows improved overall performance in terms of the normalized mean square error (NMSE) and bit error rate (BER) relative to conventional schemes.

Analytical Evaluation of Behavior of Precast PSC Box Curve Bridge Based on Design Variables (프리캐스트 PSC 중공 박스 곡선교의 설계변수에 관한 해석적 거동 평가)

  • Kim, Sung-Bae;Kim, Sung-Jae;Park, Jeong-Cheon;Uhm, Ki-Ha;Kim, Jang-Ho Jay
    • Journal of the Korea Concrete Institute
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    • v.26 no.3
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    • pp.267-275
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    • 2014
  • Recently, the construction of curved bridge has increased, thus researchers perform the analytic studies on PSC curved bridge. However, the grid analysis method that are mostly used in the construction industry is not adequate to acquire the precise behavior evaluation of curved PSC briges. Therefore, the precise finite element analysis considering the effective variables were performed to establish the basis for the design method of curved PSC bridge by using 3D elements and bar element. The evaluated variables in this analysis were the number of girders, loading point, section figure, change of prestressing force. The results show the load carrying capacity of the 3 girder type bridge is 200% of that of the 2 girder type, and that applying load on outer girder makes the load resistance capacity and the deflection deviation of 2 girders smaller. The structural capacity of the bridge is improved when the section size is increased, but the efficiency of it is not sufficient enough compare to that of the change of prestressing forces. The change of prestressing forces shows that the camber and the load carrying capacity are linearly increased as PS force is increased. Moreover, when the PS force applied on outer girder is increased than that of inner girder, the deviation of deflection the girders decreases, thereby the stability of the bridge is enhanced.

Consulting Method and Its Applied Case to Improve Management Capability of Agricultural Firms Based on the Multi-contingency Organization Theory (다중조직이론 기반의 농업경영체 경영관리능력 향상을 위한 컨설팅 기법과 사례)

  • Jang, Ikhoon;Moon, Junghoon;Choe, Young Chan
    • Journal of Agricultural Extension & Community Development
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    • v.21 no.4
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    • pp.1149-1189
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    • 2014
  • Nowadays, many farmers use online management diagnosis tool developed by Rural development agency(RDA) for the purpose of self-diagnosis of their farm management. Database(DB) was created using the diagnosis results and has been used for agri-firm management consulting. However, the amount of diagnosis data in the DB has been decreasing year by year. This means that the diagnosis tool of RDA did not reach farmers' expectation. Therefore it is necessary to develop a practical consulting tool which is applicable for various types of agri-firm management. This study introduces a management diagnosis tool and consulting method based on multi-contingency organization theory and value chain model for the purpose of improving existing tools and methods. The consulting method based on multi-contingency organization theory shows the core strategy of agri-firms by two different ways such as "efficiency-oriented" direction and "effectiveness-orientated" direction. Also, this method emphasizes that the performance of firm can be achieved when subelements of firm activities follow the same direction with the orientation of core strategy. The important thing is the right firm management activity fitted to its strategic direction. Through this action, limited firm resources can be optimized. In order to make itself understand, this study shows a practical example applied by this method from actual agri-firms.

Optimistic Concurrency Control with Update Transaction First for Broadcast Environment : OCC/UTF (방송환경에서 갱신 거래 우선 낙관적 동시성 제어 기법)

  • Lee, Uk-Hyeon;Hwang, Bu-Hyeon
    • The KIPS Transactions:PartD
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    • v.9D no.2
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    • pp.185-194
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    • 2002
  • Most of mobile computing systems allow mostly read-only transactions from mobile clients for retrieving various types of Information such as stock data, traffic information and news updates. Since previous concurrence control protocols, however, do not consider such a particular characteristics, the performance degradation occurs when previous schemes are applied to the broadcast environment. In this paper, we propose OCC/UTF(Optimistic Concurrence Control with Update Transaction First) that is most appropriate for broadcast environment. OCC/UTF lets a query transaction, that has already read the data item which was invalidated by update transaction, read again the same data item without the abort of the query transaction due to non-serializability. Therefore, serializable order is maintained and the query transaction is committed safely regardless of commitment of update transactions. In OCC/UTF, Clients need not require server to commit their query transactions. Because of broadcasting the validation reports including values updated recently to clients, it reduces the overhead of requesting recent values from the server and the server need not also re-broadcast the newest values. As a result, OCC/UTF makes full use of the asymmetric bandwidth. It can also improve transaction throughput by increasing the commit ratio of query transactions as much as possible.

Review on the Three-Dimensional Magnetotelluric Modeling (MT 법의 3차원 모델링 개관)

  • Kim, Hee-Joon;Nam, Myung-Jin;Song, Yoon-Ho;Suh, Jung-Hee
    • Geophysics and Geophysical Exploration
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    • v.7 no.2
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    • pp.148-154
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    • 2004
  • This article reviews the development of three-dimensional (3-D) magnetotelluric (MT) modeling. The 3-D modeling of electromagnetic fields is essential in understanding the physics of MT soundings, and in implementing an inversion method to reconstruct a 3-D resistivity image. Although various numerical schemes have been developed over the last two decades, practical methods have been quite limited. However, the recent rapid improvement in computer speed and memory, as well as the advance in iterative solution algorithms for a large system of equations, makes it possible to model the MT responses of complex 3-D structures, which have been very difficult to simulate before. The use of staggered grids in finite difference method has become popular, conserving a magnetic flux and an electric current and allowing for realistic discontinuous fields. The convergence of numerical solutions has been greatly accelerated by adopting Krylov subspace methods, proper preconditioning techniques, and static divergence corrections. The vector finite-element method using edge elements is also free from the discontinuity problem, and seems a natural choice for modeling complex structures including irregular topography because its flexibility allows one to capture full geometric complexity.

Formulation and ink-jet 3D printability of photo curable nano silica ink (광경화 나노 실리카 잉크의 합성 및 잉크젯 프린팅 적층 특성평가)

  • Lee, Jae-Young;Lee, Ji-Hyeon;Park, Jae-Hyeon;Nahm, Sahn;Hwang, Kwang-Taek;Kim, Jin-Ho;Han, Kyu-Sung
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.29 no.6
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    • pp.345-351
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    • 2019
  • Recently, ink-jet printing technology has been applied for various industries such as semiconductor, display, ceramic tile decoration. Ink-jet printing has advantages of high resolution patterning, fast printing speed, high ink efficiency and many attempts have been made to apply functional materials with excellent physical and chemical properties for the ink-jet printing process. Due to these advantages, research scope of ink-jet printing is expanding from conventional two-dimensional printing to three-dimensional printing. In order to expand the application of ink-jet printing, it is necessary to optimize the rheological properties of the ink and the interaction with the substrate. In this study, photo curable ceramic complex ink containing nano silica particles were synthesized and its printability was characterized. Contact angle of the photo curable silica ink were modified by control of the ink composition and the surface property of the substrate. Effects of contact angle on printing resolution and three-dimensional printability were investigated in detail.

A Study on Hazards Assessment of Electrostatic Firing Explosion of Working Wears at LPG Stations in Korea (한국의 LPG 충전소에 있어서 작업복의 정전기에 의한 화재 및 폭발 위험성에 관한 연구)

  • Cho young doo;Koo Ja Hyeuk;Choi Kwang Seo;Seo Dae Won;Joung Jae Hee;Takeuchi Manabu
    • Journal of the Korean Institute of Gas
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    • v.4 no.4 s.12
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    • pp.20-24
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    • 2000
  • The electrostatic safety consciousness of safety manager were investigated through questionnaires sent to liquid petroleum gas stations in Korea. In addition, hazards of fire and explosion due to electrostatic on synthetic-polymer-wears and cotton-wears were estimated experimentally. The results of questionnaires indicate most workers wear their working clothes indiscreetly owing to lack of knowledge of preventing electrostatic hazards. The amounts of electrostatic charge generated in synthetic-polymer-wears were 1.79, 1.44 and 1.02 $\mu$C in winter, spring and autumn and summer, respectively. All these values exceed the limit of working wears of 0.60$\mu$C requested by Korea Standard(KS K-7807) for preventing electrostatic hazards, which means hazards may occur. While, the charge in cotton-wears were in the range of 0.42 to 0.52$\mu$C, which suggests that the cotton-wears investigated in this study have no problem of hazards. Therefore workers, visual and experiential education are necessary for elevating the standard of on electrostatics. It is also necessary to establish standards of wearing for preventing electrostatic hazards.

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Basic Research on Improvement Schemes for the Limit of changing Current State of the Cultural Properties (문화재 현상변경허용기준 제도개선을 위한 기초연구)

  • Cho, Hong-Seok;Park, Hyun-Joon;Park, Jun-Sun
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.32 no.4
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    • pp.105-119
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    • 2014
  • With its growing awareness by public today, along with our heritage gaining higher standing - such as being listed as World Heritage - the needs for managing cultural heritage that meet global standard is required, and public's interest towards national heritage growing higher, Cultural Heritage Administration is actively pursuing related projects for scenic amenity that include systematic preserve/manage/restore the heritage including surrounding environment, also propose harmonious landscape. 1,834 cases of allowance limit for state-designated cultural heritage change are prepared as part of the plan, and the standards are being expanded actively towards designated cultural heritage across the country, contributing towards administrative efficiency and living conditions of the locals significantly. However, some definitions are unclear and possible complaints might arise when applied due to choice of the law, this research prepares the base material for efficient management of the establishment by diagnosing overall operational status and proposing alternatives towards the limit and improvements after reviewing the result. Through this, we expect to see establishment of policies for better management of cultural heritage and its scenic amenity via maximizing administrative efficiency, whilst positively enhance resident satisfaction around the heritage area as well as settling the regulations in short term.

The Analysis of effectiveness of the rainfall harvesting system by using infiltration-storage in the catchment area (유역 침투-저류방식을 이용한 빗물이용시설의 효과 분석)

  • 최계운;정기일;윤용진;현지환
    • Proceedings of the Korea Water Resources Association Conference
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    • 2004.05b
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    • pp.1213-1218
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    • 2004
  • 인류의 발전을 주도하였던 수자원은 현대에 이르러 음용수, 공업용수, 농업용수 등의 사용목적을 가지고 활용되는 한편 하천, 호수 등 자연환경과 어우러져 인간의 삶을 윤택하게 해주는 기능을 동반하여 다양한 형태로 활용되기에 이르렀다. 그러나, 수요 증가에 따른 개발증가로 수자원 부존량을 점차적으로 저하시키고 있고, 산업의 발전에 부가되는 환경 오염 등의 영향으로 현재 활용이 가능한 수자원의 양은 점차 줄어들고 있는 추세이다. 직접유출량이 발생하는 포장 면적이 증가할수록 침투가 가능한 면적이 줄어들어, 강우시 발생하는 다량의 수자원을 활용하지 못하고 하천으로 방류하게 되므로 점차 수자원 부족 현상이 가시화되고 있는 현 시점에서는 적극적인 활용 대책의 마련이 반드시 필요한 실정이다. 이와 같은 이유로 미국, 일본, 유럽 등 선진국에서는 빗물을 받아 활용할 수 있는 빗물이용시설에 대한 연구와 실제 적용을 통해 수자원의 효율적 활용을 유도하고 있으면, 국내의 경우 1990년대 중반부터 유출저감시설 연구 및 시범지역 적용을 시작으로 현재 빗물이용시설을 포함하는 연구가 활발하게 진행되고 있다. 빗물이용시설은 활용 면적에 따라서 건물의 옥상면을 통하여 유출되는 빗물을 저류하여 활용하는 방식과, 일정 면적에 내리는 빗물을 침투-저류하여 활용하는 두 가지의 방식으로 크게 구분 할 수 있다. 본 연구에서는 두 가지 방법 중, 유역 침투-저류 방식을 이용한 빗물이용시설에서의 강우강도에 따른 유출량 및 저류량 변화를 분석하고 아울러 침투-저류 방식을 활용하는 경우, 수질 변화를 검토하는 실험을 통하여 유역 저류-침투방식을 활용한 빗물이용시설의 적용성 여부를 확인하고자 한다.적법의 불확실도 $5\%\~10\%$에 비교하여 $5\%$ 내외의 정확도 수준을 지니고 있어 정확도 향상을 기대할 수 있다. 경제적인 측면에서도 매년 측정사업에 소요되는 비용과 비교하였을 때 장기적으로는 경제적인 방법이 될 수 있다. 하천수 등의 상호 관계 분석을 통해 장기간의 유역 물순환체계 변화를 분석할 수 있었다.골풀과, 닭의장풀과가 각 1종씩으로, 조사지점( I )보다 좀 더 많은 종이 분포하는 것으로 조사되었다. 또한 어류는 조사지점( I )에서 3회에 걸쳐 총 396개체가 채집되어 3목 8과 21종이었다. 이 중 한국 고유종은 11종이었고, 외래 어종은 검정우럭과 2종이 조사되었으며, Zacco platypus(피라미), Zacco temmincki(갈겨니), Acheilongnathus koreanus(칼납자루), Odontobutis platycephala(동사리), Coreoleuciscus splendidus(쉬리) 순으로 분포하고 있었고, Acheilognathus signifer(묵납자루)는 댐 건설 전에는 많이 분포하였으나 현장조사에서 서식을 확인 할 수 언어 개체수의 큰 감소내지 멸종된 것으로 추정되었다.에서 동시에 시행하였다. 수술 후 1년 내 시행한 심초음파에서 모든 환아에서 단지 경등도 이하의 승모판 폐쇄 부전 소견을 보였다. 수술 후 조기 사망은 없었으며, 합병증으로는 유미흉이 한 명에서 있었다. 술 후 10개월째 허혈성 확장성 심근증이 호전되지 않아 Dor 술식을 시행한 후 사망한 예를 제외한 나머지 6명은 특이 증상 없이 정상 생활 중이다 결론: 좌관상동맥 페동맥이상 기시증은 드물기는 하나

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