• Title/Summary/Keyword: Dynamic efficiency

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Implementation of the mobility for Location Searching in Broadband Intelligence Wireless ATM Networks (광대역 지능 무선 ATM 망에서 위치 탐색을 위한 이동성 구현)

  • 정운석;박광채
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.7 no.3
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    • pp.461-467
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    • 2003
  • This paper proposes the method of mobility implementation for location searching in the intelligence wireless ATM networks that expand and apply standard broadband signaling capabilities, and analyze the performance based on the numerical algorithm. The existing B-ISDN UNI protocol stack demands the location search mechanism to determine the location of mobile terminal in the wireless ATM networks because it use single protocol through the fixed PTP interface or PTM interface that don't support terminal mobility. The proposed method make possible the dynamic mobility at a part of wireless access by minimizing the signaling load without a falling-off in system performance by using the intelligence network technology according to the expansion of ATM and B-ISDN signaling integration based on the fixed networks. We implemented the performance analysis by MFC modeling based on numerical algorithm, and realized the efficiency of expenses by carrying out the comparative signaling performance evaluation to measure the relative gains of location search service in the intelligence wireless ATM system. The obtained results have the flexibility to operate in the public B-ISDN network environment without a change of existing B-ISDN/ATM NNI signaling reference to support the wireless ATM access system, and can easily expand to correspond to terminal mobility and various multimedia services in the next broadband PCS.

Seismic Performance of Special Shear Wall Structural System with Effectively Reduced Reinforcement Detail (완화된 단부 배근상세를 갖는 특수전단벽 구조시스템의 내진성능평가)

  • Chun, Young-Soo;Lee, Ki-Hak;Lee, Hyo-Won;Park, Young-Eun;Song, Jin-Kyu
    • Journal of the Korea Concrete Institute
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    • v.25 no.3
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    • pp.271-281
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    • 2013
  • The current seismic design code prescribes that a structural wall should be designed as a special shear wall when the building height is more than 60 m and its seismic design category is classified as D. However, the use of a special shear wall has a negative effect on constructability and economic efficiency. In the present study, the seismic performance of a special shear wall and a special shear wall with relaxed reinforcement detail was evaluated through a cyclic reversal loading test. The specimens were constructed to measure the results of the experimental variable regarding the reinforcement details of the special boundary element. Next, the seismic performances of a special shear wall structural system and that of a special shear wall structural system with relaxed reinforcement detail was evaluated by methods proposed in the FEMA P695. The cyclic reversal loading test results of this study showed that the performance of the shear wall with relaxed reinforcement detail was almost similar to the performance of a special shear wall and has the performance which requested from standard. The results of the seismic evaluation showed that all special shear walls with relaxed reinforcement detail are satisfied with the design code and seismic performance.

Understanding and predicting physical properties of rocks through pore-scale numerical simulations (공극스케일에서의 시뮬레이션을 통한 암석물성의 이해와 예측)

  • Keehm, Young-Seuk;Nur, Amos
    • 한국지구물리탐사학회:학술대회논문집
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    • 2006.06a
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    • pp.201-206
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    • 2006
  • Earth sciences is undergoing a gradual but massive shift from description of the earth and earth systems, toward process modeling, simulation, and process visualization. This shift is very challenging because the underlying physical and chemical processes are often nonlinear and coupled. In addition, we are especially challenged when the processes take place in strongly heterogeneous systems. An example is two-phase fluid flow in rocks, which is a nonlinear, coupled and time-dependent problem and occurs in complex porous media. To understand and simulate these complex processes, the knowledge of underlying pore-scale processes is essential. This paper presents a new attempt to use pore-scale simulations for understanding physical properties of rocks. A rigorous pore-scale simulator requires three important traits: reliability, efficiency, and ability to handle complex microstructures. We use the Lattice-Boltzmann (LB) method for singleand two-phase flow properties, finite-element methods (FEM) for elastic and electrical properties of rocks. These rigorous pore-scale simulators can significantly complement the physical laboratory, with several distinct advantages: (1) rigorous prediction of the physical properties, (2) interrelations among the different rock properties in a given pore geometry, and (3) simulation of dynamic problems, which describe coupled, nonlinear, transient and complex behavior of Earth systems.

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Determination of Aroma Components in Pinus densiflora (Pine Needles) Studied by Using Different Extraction Methods (추출방법에 따른 솔잎의 휘발성 성분 조성 비교)

  • Lee Jae-Gon;Lee Chang-Gook;Baek Shin;Kwon Young-Ju;Jang Hee-Jin;Kwag Jae-Jin;Rhee Moon-Soo;Lee Gae-Ho
    • The Korean Journal of Food And Nutrition
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    • v.19 no.2
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    • pp.161-168
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    • 2006
  • The efficiency of six different extraction methods for the analysis of aroma components from pine needle(P. densiflora) was compared by gas chromatography-mass selective detector(GC-MSD). The six methods were dynamic headspace(DHS), reduced pressure headspace(RPHS), solid-phase microextraction(SPME), simultaneous distillation-extraction(SDE), supercritical fluid extraction(SFE) and pyrolysis distillation extraction(PDE). A total of 65 compounds were identified by using the six different extraction methods. These compounds are classified into six categories in terms of chemical functionality: 25 hydrocarbons, 16 alcohols, 9 carbonyls, 6 esters, 7 acids, and 2 ethers. The aroma compounds having low boiling point were more abundant in DHS, RPHS, and SPME extracts. On the other hand, the aroma compounds having high boiling point were more abundants in SDE, SFE and PDE extracts. The acid compounds were extracted by heat-based extraction methods such as SDE, SFE, PDE, but not by DHS, RPHS and SPME, which used neither solvent nor heat. The oxygenated terpens, hexanal, hexanol, and hexadienal were more abundant in DHS and RPHS extracts, compared with the other methods.

A Study on the Direction of Entrepreneurship Education in Universities linked to Community (지역연계 대학창업교육 방향 연구)

  • Lee, Won-Cheul;Choi, Jong-In
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.12 no.6
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    • pp.89-98
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    • 2017
  • The dynamic entrepreneurial activities of small businesses or individual entrepreneurs seeking to enter the global market based on innovative ideas and challenging spirit in the modern society, which is trending in entrepreneurial capitalism according to the times, Leading to new growth engines. In order to promote the establishment of universities in Korea, the government has been working on 'Five-Year Plan for University Entrepreneurship Education(2013-2017)', 'Efficiency of Government Start-up Support in 2015', and 'Five-Year Basic Plan for Activation of Industry-University Cooperation(2016-2020)'. However, there are still practical limitations in spite of the efforts made by universities and research institutes to revitalize start-ups. As a way to overcome these limitations, this study aims to systematize the entrepreneurship education of the university, and examines the role of changing universities and theory of clusters and the entrepreneurship education. In addition, we will look at the factors of creative university culture centering on the representative cases of the Innovation University in US, and present a conceptual framework for cluster-based entrepreneurship education for the purpose of 'successful entrepreneurship' which is different from 'start-up success'. The conceptual framework of cluster-based entrepreneurship education is based on the establishment of 'Integrated Entrepreneurship Education Platform' to revitalize start-ups centered on university technology. At the same time, this framework focuses on the three factors of talent, technology, and culture based on the relevant theories and examples, and emphasizes the clustering of entrepreneurial resources, entrepreneurial policies and leadership that should be involved in entrepreneurship education.

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Optimal Design for Marker-assisted Gene Pyramiding in Cross Population

  • Xu, L.Y.;Zhao, F.P.;Sheng, X.H.;Ren, H.X.;Zhang, L.;Wei, C.H.;Du, L.X.
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.6
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    • pp.772-784
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    • 2012
  • Marker-assisted gene pyramiding aims to produce individuals with superior economic traits according to the optimal breeding scheme which involves selecting a series of favorite target alleles after cross of base populations and pyramiding them into a single genotype. Inspired by the science of evolutionary computation, we used the metaphor of hill-climbing to model the dynamic behavior of gene pyramiding. In consideration of the traditional cross program of animals along with the features of animal segregating populations, four types of cross programs and two types of selection strategies for gene pyramiding are performed from a practical perspective. Two population cross for pyramiding two genes (denoted II), three population cascading cross for pyramiding three genes(denoted III), four population symmetry (denoted IIII-S) and cascading cross for pyramiding four genes (denoted IIII-C), and various schemes (denoted cross program-A-E) are designed for each cross program given different levels of initial favorite allele frequencies, base population sizes and trait heritabilities. The process of gene pyramiding breeding for various schemes are simulated and compared based on the population hamming distance, average superior genotype frequencies and average phenotypic values. By simulation, the results show that the larger base population size and the higher the initial favorite allele frequency the higher the efficiency of gene pyramiding. Parents cross order is shown to be the most important factor in a cascading cross, but has no significant influence on the symmetric cross. The results also show that genotypic selection strategy is superior to phenotypic selection in accelerating gene pyramiding. Moreover, the method and corresponding software was used to compare different cross schemes and selection strategies.

A Study on the Ship Channel Design Method using Variable Bumper Area Model (I) (가변범퍼영역모델을 이용한 항로설계기법(I))

  • Jeong Dae-Deug;Lee Joong-Woo
    • Journal of Navigation and Port Research
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    • v.29 no.1 s.97
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    • pp.9-15
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    • 2005
  • To design ship channel is one of important factors for planning and developing a port. In most case, the core factors for designing ship channel are the layout and width of channel provided the net underkeel clearance is secured to be safe enough to pass. In this study, Variable Bumper Area(VBA) model is applied to design and assess ship channel. This model reflects ship's particular, ship domain theory, ship speed and mariner's ship handling skill and experience, especially external forces which cause leeway, set and drift and the change of ship maneuvering characteristics. A real time, full mission shiphandling simulator is used to analyze ship dynamic data according to mariner's ship control, external forces, ete. This model defines Domain degree and Domain-index for assessing the efficiency and safety of the channel. The proposed model is applied to Ulsan new port plan which has a channel width of 1.5 times the length of the largest vessel, a radius of 5 times the length of the largest vessel in a curve of 57 degree centerline angle and SBM facility adjacent to the lateral edge of channel. The result of this study shows that the width of the channel and radius of channel curve are suitable for the target ship but the difficulty of ship handling is caused by the large course change and SBM located in the vicinity of channel.

A study on vibration control of the engine body for a large scale diesel engine using the semi-active controlled hydraulic type of top bracing (준능동형 유압식 톱브레이싱을 이용한 선박용 저속 2행정 디젤엔진의 본체 진동제어)

  • Lee, Moon-Seek;Kim, Yang-Gon;Hwang, Sang-Jae;Lee, Don-Chool;Kim, Ue-Kan
    • Journal of Advanced Marine Engineering and Technology
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    • v.38 no.6
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    • pp.632-638
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    • 2014
  • Nowadays, as part of an effort to increase the efficiency of propulsion shafting system, the revolution of the main diesel engine in CMCR(Contract Maximum Continuous Rating) is reduced whereas the stiffness of hull structure supporting the main diesel engine is relatively flexible. However, vibration problems related with resonant response of main diesel engine are increasing although top bracing is installed between the main diesel engine and the hull structures to increase natural frequency of engine body above CMCR to avoid resonant phenomenon. In this study, the dynamic characteristic of top bracing is reviewed by analyzing measuring results of general cargo ships which apply the hydraulic type instead of the friction type to control the natural frequency and the vibration of the engine body. Moreover, considering the vibration characteristic of the engine body and the hydraulic type of the top bracing by varying the number of top bracing, authors suggest the more effective way to control the vibration of the engine body despite of lower stiffness of the hull structure than in the past when the hydraulic type of top bracing is used.

Control of torsional vibration for propulsion shafting with delayed engine acceleration by optimum design of a viscous-spring damper (점성-스프링 댐퍼 최적화 설계를 이용한 엔진 증속지연 특성을 갖는 추진축계 비틀림진동 제어)

  • Kim, Yang-Gon;Hwang, Sang-Jae;Kim, Young-Hwan;Kim, Sang-Won;Cho, Kwon-Hae;Kim, Ue-Kan
    • Journal of Advanced Marine Engineering and Technology
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    • v.40 no.7
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    • pp.580-586
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    • 2016
  • The ultra-long stroke engine was developed to generate greater power at lower speeds than previous designs to enhance the propulsion efficiency. The torsional exciting force, on the other hand, was increased significantly. Therefore, it is possible to control the torsional vibration of its shaft system equipped with the fuel efficient ultra-long stroke engine by adopting a damper although the torsional vibration could be controlled adequately by applying tuning and turning wheels on the engine previously. In this paper, the dynamic characteristics of a viscous-spring damper used to control the torsional vibration of the corresponding shaft system are reviewed and then examined to determine what vibration characteristics might be used to optimize the viscous-spring damper. In some cases, operators of eco-ships have recently experienced the problem of delayed RPM acceleration. It has been suggested that the proper measures for controlling the torsional vibration in the shaft system should involve adjusting the design parameters of its damper determined by the optimum damper design theory to avoid the fatigue damage of shafts.

Analysis of Performance, Energy-efficiency and Temperature for 3D Multi-core Processors according to Floorplan Methods (플로어플랜 기법에 따른 3차원 멀티코어 프로세서의 성능, 전력효율성, 온도 분석)

  • Choi, Hong-Jun;Son, Dong-Oh;Kim, Jong-Myon;Kim, Cheol-Hong
    • The KIPS Transactions:PartA
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    • v.17A no.6
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    • pp.265-274
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    • 2010
  • As the process technology scales down and integration densities continue to increase, interconnection has become one of the most important factors in performance of recent multi-core processors. Recently, to reduce the delay due to interconnection, 3D architecture has been adopted in designing multi-core processors. In 3D multi-core processors, multiple cores are stacked vertically and each core on different layers are connected by direct vertical TSVs(through-silicon vias). Compared to 2D multi-core architecture, 3D multi-core architecture reduces wire length significantly, leading to decreased interconnection delay and lower power consumption. Despite the benefits mentioned above, 3D design technique cannot be practical without proper solutions for hotspots due to high temperature. In this paper, we propose three floorplan schemes for reducing the peak temperature in 3D multi-core processors. According to our simulation results, the proposed floorplan schemes are expected to mitigate the thermal problems of 3D multi-core processors efficiently, resulting in improved reliability. Moreover, processor performance improves by reducing the performance degradation due to DTM techniques. Power consumption also can be reduced by decreased temperature and reduced execution time.