• Title/Summary/Keyword: Loose Coupling

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The Effect of Ni Atoms Inserted in Ag Spacer on the Magnetic Property of Ni/Ag(Ni at %)/Ni Trilayered Films

  • Lee, S.J.
    • Journal of Magnetics
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    • v.4 no.4
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    • pp.128-130
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    • 1999
  • We have measured the magnetization of Ni/Ag(Ni at %)/Ni (50$\AA$/30 $\AA$/50 $\AA$) trilayered films including Ni atoms inserted in non-magnetic Ag spacer. The magnetization as a function of applied field at 5 K and as a function of temperature at 100 Oe were investigated respectively using SQUID magnetometer. In these measurements peaks of magnetization at some critical temperatures were observed in all the samples. The antiferromagnetic coupling energy between neighboring Ni layers showed oscillatory behaviors according to the amounts of the Ni atoms inserted in Ag spacer. Loose spin model suggested by slonczews야 was used to explain such results.

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Loose Coupling Approach of CFD with a Free-Wake Panel Method for Rotorcraft Applications

  • Lee, Jae-Won;Oh, Se-Jong;Yee, Kwan-Jung;Kim, Sang-Hun;Lee, Dong-Ho
    • International Journal of Aeronautical and Space Sciences
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    • v.8 no.1
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    • pp.1-9
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    • 2007
  • As a first step toward a complete CFD-CSD coupling for helicopter rotor load analysis, the present study attempts to loosely couple a CFD code with a source-double panel method. The far-field wake effects were calculated by a time-marching free vortex wake method and were implemented into the CFD module via field velocity approach. Unlike the lifting line method, the air loads correction process is not trivial for the source-doublet panel method. The air loads correction process between the source-doublet method and CFD is newly suggested in this work and the computation results are validated against available data for well-known hovering flight conditions.

A Wideband 3dB Quadrature Coupler Design Using N-Section Parallel-Coupled Lines (N단 평행 결합 선로를 이용한 90$^{\circ}$광대역 3dB결합기 설계)

  • 조정훈;윤상원
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2001.11a
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    • pp.180-183
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    • 2001
  • 본 논문에서는 N개의 평행 결합선로를 이용한 3dB 결합기를 해석하였으며, 유도된 식에 의하여 최소의 단수와 크기로 3dB 결합기를 설계하였다. 기존의 Spectral Domain상에서 N단 평행 결합선로의 복잡한 관계식 유도를 S 파라미터 관계식으로 간단히 유도 하였으며, 유도된 식의 타당성을 위해 실제 제작 검증하였다. 제작된 결합기는 Loose coupling의 평행 결합 선로의 광대역 특성을 그대로 이용하기 때문에 Lange Coupler와 같은 높은 임피던스와 Tight coupling을 구현 할 필요가 없으며, wire bonding도 용이하게 된다. 최소의 단수로 구현하기 위해 RT/Duroid의 R06006과 같은 높은 유전율과 두꺼운 기판을 사용하여 2단으로 3dB 구현이 가능하게 하였다. 제작결과 3.6GHz에서5.5GHz로 대략 42%(0.5dB imbalance) 정도의 광대역특성을 가지고 위상오차도 1$^{\circ}$내외의 결합기를 구현할 수 있었고 격리도 특성 또한 대역 내에서 15dB 내외의 특성을 보였다.

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Tightly Coupled Integration of Ranking SVM and RDBMS (랭킹 SVM과 RDBMS의 밀결합 통합)

  • Song, Jae-Hwan;Oh, Jin-Oh;Yang, Eun-Seok;Yu, Hwan-Jo
    • Journal of KIISE:Databases
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    • v.36 no.4
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    • pp.247-253
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    • 2009
  • Rank learning and processing have gained much attention in the IR and data mining communities for the last decade. While other data mining techniques such as classification and regression have been actively researched to interoperate with RDBMS by using the tightly coupled or loose coupling approaches, ranking has been researched independently without integrating into RDBMS. This paper proposes a tightly coupled integration of the Ranking SVM into MySQL in order to perform the rank learning task efficiently within the RDBMS. We implemented new SQL commands for learning ranking functions and predicting ranking scores. We evaluated our tightly coupled integration of Ranking SVM by comparing it to a loose coupling implementation. The experiment results show that our approach has a performance improvement of $10{\sim}40%$ in the training phase and 60% in the prediction phase.

System Modeling for Web Service based on Service-Oriented Architecture (서비스 지향 아키텍처를 기반으로 한 웹서비스 시스템 모델링)

  • Lee, Seong-Kyu;Jin, Chan-Uk;Kim, Tai-Suk
    • Journal of the Korea Society for Simulation
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    • v.16 no.1
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    • pp.49-57
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    • 2007
  • Service-Oriented Architecture(SOA) is improving rapidly in IT Environment. Enterprise companies interest in implementation infrastructure based on SOA to adapt quick changes of large and complex distributed environment. SOA is a component model that inter-relates the different functional units of an application, called services, through interfaces and contacts between theses services. In this paper, we studied the concept of the relationship between SOA and standard web service core and therefore, we model the web service based on SOA. We implemented the application and business service architecture using web service that include the XML and SOAP. We confirmed that how the each SOA characters like interoperability, reusability, scalability and flexible business process adapted to web service and present a web service modeling that is maintained the neutrality using loose service coupling through the method of service model process and web service architecture designing methodology based on SOA.

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Service Identification of Component-Based For Extending Service-Oriented Computing System (서비스지향 컴퓨팅 시스템으로의 확장을 위한 컴포넌트 기반의 서비스 식별)

  • Choi, Mi-Sook;Lee, Seo-Jeong;Lee, Jong-Suk;Yang, Seung-Won
    • Journal of Korea Multimedia Society
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    • v.11 no.5
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    • pp.710-727
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    • 2008
  • Service-oriented computing systems have been issued by their properties of reducing software development time and effort by reusing functional service units. The reusability of services can effectively promote through loose coupling between services. But strong associations of object-oriented systems such as inheritance and aggregation create a rather tight coupling between objects. The component-based systems without inheritance and aggregation create a loose coupling between components. Thus components provide service realization at runtime using the functionality provided by their interfaces. Therefore legacy component-based systems need to have service-oriented computing concept in order to support functional service units efficiently. Also, conventional methods for service-oriented computing system have not suggested the clear classification of service layers, the clear service identification guideline introducing service layers and a service mapping method between serviceces of each layer. Therefore we suggest the service classification and the identification guideline of business view and implementation view introducing layers and propose a mapping between two views. That is, we research service layers, service identification, diversified service sizes and a service mapping method between services of each layer. This can be applied to legacy component-based system to extend to the service-oriented computing system.

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Airloads and Structural Loads Analysis of LCH Rotor Using a Loose CFD/CSD Coupling (유체-구조 연계해석을 통한 소형민수헬기(LCH) 공력 및 구조하중 해석)

  • Lee, Da-Woon;Kim, Kiro;Yee, Kwan-Jung;Jung, Sung-Nam
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.47 no.7
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    • pp.489-498
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    • 2019
  • The airloads and structural loads of Light Civil Helicopter (LCH) rotor are investigated using a loose CFD/CSD coupling. The structural dynamics model for LCH 5-bladed rotor cwith elastomeric bearing and inter-bladed damper is constructed using CAMRAD-II. Either isolated rotor or rotor-fuselage model is used to identify the effect of the fuselage on the aeromechanics behavior at a cruise speed of 0.28. The fuselage effect is shown to be marginal on the aeromechanics predictions of LCH rotor, though the effect can be non-negligible for the tail structure due to the prevailing root vortices strengthened by the fuselage upwash. A lifting-line based comprehensive analysis is also conducted to verify the CFD/CSD coupled analysis. The comparison study shows that the comprehensive analysis predictions are generally in good agreements with CFD/CSD coupled results. However, the predicted comprehensive analysis results underestimate peak-to-peak values of blade section airloads and elastic motions due to the limitation of unsteady aerodynamic predictions. Particularly, significant discrepancies appear in the structural loads with apparent phase differences.

The Design of a Class Diagram Authorization Tool based on the MVC Design Pattern (MVC 디자인 패턴에 기반한 클래스 다이어그램 저작도구의 설계)

  • Kim, Jae-Hoon;Kim, Yun-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.12
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    • pp.2707-2715
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    • 2010
  • This paper suggests a implements and a design of class diagram authorization tool based on the MVC pattern. It defines and descries the structure of ClassInformation, ScreenDisplay and ToolManager. ClassInformation is responsible for processing or handling information of a diagram. ScreenDisplay is responsible for GUI to configure the screen of the authorization tool. ToolManager is responsible for event handling to process I/O of the authorization tool. Based on MVC pattern, ClassInformation, ScreenDisplay and ToolManager of the authorization tool are assigned each role independently. It is flexible to new requirement, because of loose coupling.

Hot and average fuel sub-channel thermal hydraulic study in a generation III+ IPWR based on neutronic simulation

  • Gholamalishahi, Ramin;Vanaie, Hamidreza;Heidari, Ebrahim;Gheisari, Rouhollah
    • Nuclear Engineering and Technology
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    • v.53 no.6
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    • pp.1769-1785
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    • 2021
  • The Integral Pressurized Water Reactors (IPWRs) as the innovative advanced and generation-III + reactors are under study and developments in a lot of countries. This paper is aimed at the thermal hydraulic study of the hot and average fuel sub-channel in a Generation III + IPWR by loose external coupling to the neutronic simulation. The power produced in fuel pins is calculated by the neutronic simulation via MCNPX2.6 then fuel and coolant temperature changes along fuel sub-channels evaluated by computational fluid dynamic thermal hydraulic calculation through an iterative coupling. The relative power densities along the fuel pin in hot and average fuel sub-channel are calculated in sixteen equal divisions. The highest centerline temperature of the hottest and the average fuel pin are calculated as 633 K (359.85 ℃) and 596 K (322.85 ℃), respectively. The coolant enters the sub-channel with a temperature of 557.15 K (284 ℃) and leaves the hot sub-channel and the average sub-channel with a temperature of 596 K (322.85 ℃) and 579 K (305.85 ℃), respectively. It is shown that the spacer grids result in the enhancement of turbulence kinetic energy, convection heat transfer coefficient along the fuel sub-channels so that there is an increase in heat transfer coefficient about 40%. The local fuel pin temperature reduction in the place and downstream the space grids due to heat transfer coefficient enhancement is depicted via a graph through six iterations of neutronic and thermal hydraulic coupling calculations. Working in a low fuel temperature and keeping a significant gap below the melting point of fuel, make the IPWR as a safe type of generation -III + nuclear reactor.

Formal Business Plans as Myth and Ceremony: Education and Practical Implications

  • Mahdjoubi, Darius;Gibson, David V.
    • World Technopolis Review
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    • v.4 no.4
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    • pp.222-237
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    • 2015
  • Business plan competitions and related education are common activities to regions that are, or desire to be, important innovative and start-up regions. The literature is contradictory regarding the value of formal business plans (FBPs) toward venture planning, capital acquisition, and education. This study analyzes the relevant literature and sample of 35 FBPs to assess these contradictions. We propose the theoretical constructs of "myth and ceremony" to explain the loose coupling of FBPs to real business environments, an observation consistent with theory that suggests organizations perpetuate the myths of their institutional environment to maintain their legitimacy. We offer Action Business Planning as an alternative to more accurately address the realities of venture creation and survival, and for education.