• 제목/요약/키워드: structure-level

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레벨 프리페칭 기법을 이용한 향상된 주기억장치 상주형 색인구조 (IpCSB+ - tree : An Enhanced Main Memory Index Structure Employing the Level Prefetching Technique)

  • 홍현택;강태호;유재수
    • 인터넷정보학회논문지
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    • 제4권6호
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    • pp.75-86
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    • 2003
  • 주기억장치 상주형 색인구조에서는 2차 캐쉬 실패가 성능에 매우 큰 영향을 미친다. 기존에 제안된 주기억장치 상주형 색인구조들은 2차 캐쉬 실패를 고려하긴 했지만 여전히 트리의 각 레벨을 접근할 때는 2차 캐쉬 실패가 발생한다. 본 논문에서는 이러한 문제점을 인식하고 트리 순회 시 각 레벨을 방문할 때도 캐쉬 실패가 발생하지 않는 주기억장치 색인구조를 제안한다. 제안하는 색인구조인 IpCSB+-트리는 다음 레벨에서 방문할 가능성이 있는 노드들을 프리페치하여 다음 레벨을 방문할 때도 캐쉬 실패가 발생하지 않도록 한다. 또한, 기본적인 구조는 노드그룹 개념을 이용하여 노드의 팬-아웃을 증가시키는 CSB+-트리에 기반하지만 CSB+-트리의 단점인 분한 비용의 증가문제를 해결하기 위한 방법을 제안한다. 성능평가를 통해 기존의 색인구조와 비교하여 제안하는 색인구조의 우수성을 보인다.

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수직형 Feed-through 갖는 RF-MEMS 소자의 웨이퍼 레벨 패키징 (Wafer Level Packaging of RF-MEMS Devices with Vertical Feed-through)

  • 박윤권;이덕중;박흥우;김훈;이윤희;김철주;주병권
    • 한국전기전자재료학회논문지
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    • 제15권10호
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    • pp.889-895
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    • 2002
  • Wafer level packaging is gain mote momentum as a low cost, high performance solution for RF-MEMS devices. In this work, the flip-chip method was used for the wafer level packaging of RF-MEMS devices on the quartz substrate with low losses. For analyzing the EM (electromagnetic) characteristic of proposed packaging structure, we got the 3D structure simulation using FEM (finite element method). The electric field distribution of CPW and hole feed-through at 3 GHz were concentrated on the hole and the CPW. The reflection loss of the package was totally below 23 dB and the insertion loss that presents the signal transmission characteristic is above 0.06 dB. The 4-inch Pyrex glass was used as a package substrate and it was punched with air-blast with 250${\mu}{\textrm}{m}$ diameter holes. We made the vortical feed-throughs to reduce the electric path length and parasitic parameters. The vias were filled with plating gold. The package substrate was bonded with the silicon substrate with the B-stage epoxy. The loss of the overall package structure was tested with a network analyzer and was within 0.05 dB. This structure can be used for wafer level packaging of not only the RF-MEMS devices but also the MEMS devices.

한국 의류산업의 국제경쟁력 향상을 위한 결정요인 (The Determinants of International Competitiveness for the Korean Apparel Industry)

  • 백영하;박재옥
    • 한국의류학회지
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    • 제32권3호
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    • pp.474-485
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    • 2008
  • The purpose of this study is to examine the determinants and elements to enhance Korean international competitiveness, employing Porter's(1998) Diamond Model. Half of the 500 leading apparel exporters that were members of the Korea Apparel Industry Association in 2003 were selected as the target of this research. From May to June of 2003, survey questionnaires were sent to executives of these 250 companies in person or by telephone, e-mail, or fax. Seventy questionnaires were used for the final data anlysis. The items used were Reliability, Categorical Regression, and Frequency, using SPSS 11.5. The results were as follows: First, as a result of analyzing the influence of international competitiveness in Korean apparel industry, the firm's strategy, structure, and rivalry was the most influential factor. Others were related and supporting industries, government, chance, demand conditions, and factor conditions. Also, the elements that affect Korean international competitiveness were listed as the level of price competition in foreign markets, the level of labor cost, export marketing capacity, and exchange fluctuation. The most important element to improve the international competitiveness of the Korean apparel industry was a demand growth rate of the overseas markets(Demand Conditions), followed by the level of the labor costs(Factor Conditions), the capability of internationalization(Firm Strategy, Structure, and Rivalry), the change of currency(Chance), the quality and management of products(Demand Conditions), the capability of planning products(Firm Strategy, Structure, and Rivalry), free trade from 2005(Chance), and global sourcing strategy(Firm Strategy, Structure, and Rivalry). Korea's main rival country in apparel related and supporting industry factors is China. However, Korea has a higher level of technology development, quality, and price level than China.

칼라 및 모션 특징 기반 비디오 씬 분할 기법 (Video Scene Segmentation Technique based on Color and Motion Features)

  • 송창준;고한석;권용무
    • 방송공학회논문지
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    • 제5권1호
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    • pp.102-112
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    • 2000
  • 기존의 비디오 구조화 기법은 주로 샷 또는 샷 그룹 레벨에서 이루어져 왔다. 그러나 이러한 샷 레벨 구조는 사용자에게 의미(semantics)를 충분히 전달할 수 없는 단점이 있다. 이런 단점을 극복하기 위해, 최근 샷 보다 상위 레벨 구조인 비디오 씬 분할에 관한 연구가 진행되고 있다. 본 논문에서는 이러한 샷 레벨 구조의 단점을 극복하기 위해서 칼라와 모션 특징을 기반으로 한 비디오 씬 분할 기법을 제안한다. 샷 내의 다양한 칼라 분포를 반영하기 위해서 각 샷을 sub-shot으로 재분할하고, 이를 이용해 대표 프레임을 추출한다. 샷 내의 모션 특징은 MPEG-1 비디오 내의 모션 벡터를 이용한다. 유사한 컨텐트를 가지고 있는 샷을 찾기 위해서 탐색 구간내의 모션 특성을 반영한 적응적 가중치를 칼라와 모션 특징에 적용한다. 실험 결과 비교를 통해 씬의 과다 분할이나 의미 반영 면에서 기존의 씬 분할 기법보다 우수함을 보였다. 제안된 기법은 비디오를 의미 있는 계층 구조로 분할해서, 사용자에게 의미를 반영하는 씬 단위로의 브라우징이나 검색을 가능케 한다.

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Optimal design of spoke double-layer cable-net structures based on an energy principle

  • Ding, Mingmin;Luo, Bin;Han, Lifeng;Shi, Qianhao;Guo, Zhengxing
    • Structural Engineering and Mechanics
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    • 제74권4호
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    • pp.533-545
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    • 2020
  • An optimal design method for a spoke double-layer cable-net structure (SDLC) is proposed in this study. Simplified calculation models of the SDLC are put forward to reveal the static responses under vertical loads and wind loads. Next, based on an energy principle, the relationship among the initial prestress level, cross-sectional areas of the components, rise height, sag height, overall displacement, and relative deformation is proposed. Moreover, a calculation model of the Foshan Center SDLC is built and optimized. Given the limited loading cases, material properties of the components, and variation ranges of the rise height and sag height, the self-weight and initial prestress level of the entire structure can be obtained. Because the self-weight of the cables decreases with increasing of the rise height and sag height, while the self-weight of the inner strut increases, the total weight of the entire structure successively exhibits a sharp reduction, a gradual decrease, a slow increase, and a sharp increase during the optimization process. For the simplified model, the optimal design corresponds to the combination of rise height and sag height that results in an appropriate prestress level of the entire structure with the minimum total weight.

인필식 모듈러 공법을 적용한 주택건설공사의 작업분류체계 구축 및 표준 프로세스 제안 (Standard Process and Work Breakdown Structure for Housing Construction Projects using Infill Modular System)

  • 손정락;이동건;방종대;김진원
    • 토지주택연구
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    • 제10권3호
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    • pp.77-87
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    • 2019
  • In Korea, the modular construction method was applied to the construction of facilities such as military barracks and school dormitories, beginning with the pilot project of Seoul New Elementary School in 2003. In 2017, public modular houses were supplied to Busan(Yongho-dong) and Seoul(Gayang-dong), and modular housing is expected to continue to be supplied in the future. However, there is no clear construction standard for the modular housing construction yet, and there are few cases where the infill modular system is applied. Therefore, this study established the work breakdown structure and proposed a standard process focusing on the infill modular system applied to the construction of Dujeong-dong modular house in Cheonan. Level 1 of the work breakdown structure by construction stage of Infill modular was defined as modular manufacturing, assembly, and finishing process. Level 2 was defined as preparation, modular production, modular infill, modular fixing, floor plastering, building finishing, and other site finishing. Level 3 is defined as 57 detailed unit work of infill modular construction. The standard process of infill modular is proposed for the assembly stage that is commonly applicable to infill modular housing construction. The results of this study can be used for the process plan, transportation plan, lifting plan of modular housing construction.

Determinant Factors of Firm Risk - Using the Structural Equation Modeling Approach: Evidence from Indonesia

  • WULANDARI, Asih Marini;RAHAYU, Sri Mangesti;SAIFI, Muhammad;NUZULA, Nila Firdausi
    • The Journal of Asian Finance, Economics and Business
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    • 제9권8호
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    • pp.47-55
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    • 2022
  • The purpose of this study was to determine the relationship between company risk and factors such as business size, ownership structure, and leverage. The study was conducted on 142 manufacturing sector companies listed on the Indonesia Stock Exchange from 2013 to 2018. The purposive sampling method was used to select the research sample. The sample size for this study was 21 different companies. The analytical approach uses Structural Equation Modeling (SEM) with WarpPLS. According to the findings of the investigation, the size of the company has a significant influence on both the amount of leverage the company uses and the amount of risk the company takes. The level of leverage is significantly influenced by the ownership structure. However, the ownership structure does not have a significant impact on the level of risk the company; rather, leverage has a big impact on the level of risk the company faces. The findings of this study are helpful to prospective investors in measuring the risk posed by the company to make judgments regarding investments. The findings of this study are also essential for management to consider while controlling the risk of the organization.

Issues of New Technological Trends in Nuclear Power Plant (NPPs) for Standardized Breakdown Structure

  • Gebremichael, Dagem D.;Lee, Yunsub;Jung, Youngsoo
    • 국제학술발표논문집
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    • The 8th International Conference on Construction Engineering and Project Management
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    • pp.353-358
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    • 2020
  • Recent efforts to develop a common standard for nuclear power plants (NPPs) with the aim of creating (1) a digital environment for a better understanding of NPPs life-cycle management aspect and (2) engineering data interoperability by using existing standards among different unspecified project participants (e.g., owners/operators, engineers, contractors, equipment suppliers) during plants' life cycle process (EPC, O&M, and decommissioning). In order to meet this goal, there is a need for formulating a standardized high-level physical breakdown structure (PBS) for NPPs project management office (PMO). However, high-level PBS must be comprehensive enough and able to represent the different types of plants and the new trends of technologies in the industry. This has triggered the need for addressing the issues of the recent operational NPPs and future technologies' ramification for evaluating the changes in the NPPs physical components in terms of structure, system, and component (SSC) configuration. In this context, this ongoing study examines the recent conventional NPPs and technological trends in the development of future NPPs facilities. New reactor models regarding the overlap of variant issues of nuclear technology were explored. Finally, issues on PBS for project management are explored by the examination of the configuration of NPPs primary system. The primary systems' configuration of different reactor models is assessed in order to clarify the need for analyzing the new trends in nuclear technology and to formulate a common high-level PBS. Findings and implications are discussed for further studies.

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Species Composition and Stand Structure of Natural Forest, Timber-harvested Forest and Degraded Forest in the Bago Yoma Region of Myanmar

  • Oo, Thaung Naing;Lee, Don Koo
    • 한국산림과학회지
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    • 제96권5호
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    • pp.572-579
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    • 2007
  • Tree species diversity is an important aspect of forest ecosystem stability. Tree species inventories at defined sites and in minimum diameter classes give a reliable indicator of the diversity level as well as the structural stability level of a study site. This study was conducted to investigate the species composition and the stand structure of the natural forest, timber-harvested forest (logged-over forest) and degraded forest of the Oak-twin Township in the Bago Yoma Region of Myanmar. Natural forest showed the highest family and species richness in all the investigated forests. At the family level, Verbenaceae occupied the highest importance value index (IVI) in all the forest stands while teak (Tectona grandis Linn. f.) occupied the highest IVI at the species level. However, the small diameter classes of T. grandis and other commercial species were less than those of big diameter classes in all the investigated forests. This abnormal pattern of diameter distribution could be a problem for the sustainable production of commercial timber species in the near future.

한국고속철도 천안역사에 대한 소음 및 진동영향 연구 (Noise and Vibration Solutions Considering Stability Effects for High-Speed Rail ChonAn Station in Korea)

  • 권영철
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2005년도 추계학술대회 논문집
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    • pp.848-853
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    • 2005
  • The objective of this paper is to address to the providing an adequate noise and vibration solution, required for High Speed Rail while maintaining the stability criteria of the ChonAn station structure, the first constructed in Korean High Speed Railway. The significant acoustic pressure level will be induced by the high speed trains passing-by. Therefore, the high level study of this case is necessary. The acoustic pressure level of 85 dB(A) inside the ChonAn station is expected, and the spaces below concrete slab are not suitable for commercial purpose, thus installation of filtering systems (spring boxes containing viscous dampers, ballast mats and acoustic shield) are provided to reduce the effect of the noise and vibration to acceptable level of 55 dB(A). But, a major drawback of application of the previously conducted experimental results was that the actual effect of installation of filtering system was never been validated. Therefore, the acquisition of noise and vibration on the present structure were obtained and compared to the computer simulations. These predicted the behavior of the station reasonably well. Also, the installation of filtering systems gave the superior reduction on noise and vibration. This application is successfully adapted without scarifying stability criteria related to the structural stability including excessive deformations or displacements. Three traffic operation safety limits: deck vertical acceleration, deflection of the structure, and longitudinal displacement of the slab were satisfactory.

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