• Title/Summary/Keyword: domain configuration

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Thermal Stability of Nanostructured Synthetic Ferrimagnets under Applied Magnetic Fields in the 45˚ Direction

  • Han, C.W.;Han, J.K.;Lim, S.H.
    • Journal of Magnetics
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    • v.15 no.3
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    • pp.116-122
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    • 2010
  • An accurate analytical equation for the total energy in the framework of the single domain model is used to study the thermal stability of nanostructured synthetic ferrimagnets. Elliptical cells are considered that have lateral dimensions of 160 nm (long axis)$\times$80 nm (short axis) and varying values of thickness asymmetry for the two magnetic layers. The direction of the applied magnetic field, which points to the $45^{\circ}$ direction, is in the opposite direction to the thicker layer magnetization. A significant difference is observed in the applied magnetic field dependencies of the equilibrium magnetic configuration and the magnetic energy barrier when using the simplifying assumption that the self-demagnetizing field is identical in magnitude to the dipole field. At a small thickness asymmetry of 0.2 nm, for example, the magnetic energy barrier is reduced from 68 kT (T=300 K) to 6 kT at the remanent state and a progressive switching behavior changes into a critical behavior, as the simplifying assumption is used. The present results clearly demonstrate the need for an accurate analytical equation for the total energy in predicting the thermal stability of nanostructured synthetic ferrimagnets.

A Study on the Space configuration and Area of the Standard Ward in General Hospital in China (중국 종합병원 표준 병동부 공간구성 및 면적에 관한 연구)

  • Lyu, Cheng;Chai, Choul Gyun
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.24 no.2
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    • pp.55-64
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    • 2018
  • Purpose: The ward division is a representative part of the hospital, where a variety of user activities are performed. Users can be broadly categorized as patients and carers, visitors, and medical staff (doctors and nurses). The relationship between these two is a major issue with ward planning as the patient's place of life centers around the hospital room and the task of the clinical workforce centers around the nursing station (NS). Against this backdrop, the study divides the ward units of the General Hospital of China into patient areas, medical team areas, supply areas, and public domain, with the focus on the ward areas affecting most significantly in the hospital patients. Methods: The theoretical advance studies of the standard ward unit are identified by the associated guidelines, articles, and documentation. Results: This study is a summary analysis of relevant regulations, reference literature, and drawing data from the target hospital. Further work is expected to be undertaken, including further surveys and observational surveys, to produce more detailed results. Implications: It is expected that the research in this paper will provide an effective reference for the future research of China General Hospital Ward department, so as to promote and improve the work system of China General Hospital Ward department.

Vortex induced vibration analysis of a cylinder mounted on a flexible rod

  • Zamanian, Mehdi;Garibaldi, Luigi
    • Wind and Structures
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    • v.29 no.6
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    • pp.441-455
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    • 2019
  • In this study, vortex induced vibrations of a cylinder mounted on a flexible rod are analyzed. This simple configuration represents the key element of new conception bladeless wind turbine (Whitlock 2015). In this study the structure oscillations equation coupled to the wake oscillation equation for this configuration are solved using analytical perturbation method, for the first time. An analytical expression that predicts the lock-in phenomena range of wind speed is derived. The discretized equations of motion are also solved using RKF45 numerical method. The equations of motion are discretized by Galerkin method. Free vibration mode shape of the structure taking into account the discontinuity of the cross section are used as comparison function. Numerical results are compared to the analytical results, and they show a satisfying agreement. The effect of system parameters on the oscillations of structure and wake as well as on the lock-in domain are presented. Moreover, it is shown that the values of wind speed triggering the start and the stop of the lock-in phenomenon, for increasing wind speed are different from those values obtained during the reverse process, i.e., when the wind speed decreases.

Efficient Decoupling Capacitor Optimization for Subsystem Module Package

  • Lim, HoJeong;Fuentes, Ruben
    • Journal of the Microelectronics and Packaging Society
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    • v.29 no.1
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    • pp.1-6
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    • 2022
  • The mobile device industry demands much higher levels of integration and lower costs coupled with a growing awareness of the complete system's configuration. A subsystem module package is similar to a board-level circuit that integrates a system function in a package beyond a System-in-Package (SiP) design. It is an advanced IC packaging solution to enhance the PDN and achieve a smaller form factor. Unlike a system-level design with a decoupling capacitor, a subsystem module package system needs to redefine the role of the capacitor and its configuration for PDN performance. Specifically, the design of package's form factor should include careful consideration of optimal PDN performance and the number of components, which need to define the decoupling capacitor's value and the placement strategy for a low impedance profile with associated cost benefits. This paper will focus on both the static case that addresses the voltage (IR) drop and AC analysis in the frequency domain with three specific topics. First, it will highlight the role of simulation in the subsystem module design for the PDN. Second, it will compare the performance of double-sided component placement (DSCP) motherboards with the subsystem module package and then prove the advantage of the subsystem module package. Finally, it will introduce three-terminal decoupling capacitor (decap) configurations of capacitor size, count and value for the subsystem module package to determine the optimum performance and package density based on the cost-effective model.

A Modified REDP Aggregate Marker for improving TCP Fairness of Assured Services

  • Hur Kyeong;Eom Doo-Seop;Tchah Kyun-Hyon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.1B
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    • pp.86-100
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    • 2004
  • To provide the end-to-end service differentiation for assured services, the random early demotion and promotion (REDP) marker in the edge router at each domain boundary monitors the aggregate flow of the incoming in-profile packets and demotes in-profile packets or promotes the previously demoted in-profile packets at the aggregate flow level according to the negotiated interdomain service level agreement (SLA). The REDP marker achieves UDP fairness in demoting and promoting packets through random and early marking decisions on packets. But, TCP fairness of the REDP marker is not obvious as for UDP sources. In this paper, to improve TCP fairness of the REDP marker, we propose a modified REDP marker where we combine a dropper, meters and a token filling rate configuration component with the REDP marker. To make packet transmission rates of TCP flows more fair, at the aggregate flow level the combined dropper drops incoming excessive in-profile packets randomly with a constant probability when the token level in the leaky bucket stays in demotion region without incoming demoted in-profile packets. Considering the case where the token level cannot stay in demotion region without the prior demotion, we propose a token filling rate configuration method using traffic meters. By using the token filling rate configuration method, the modified REDP marker newly configures a token filling rate which is less than the negotiated rate determined by interdomain SLA and larger than the current input aggregate in-profile traffic rate. Then, with the newly configured token filling rate, the token level in the modified REDP marker can stay in demotion region pertinently fir the operation of the dropper to improve TCP fairness. We experiment with the modified REDP marker using ns2 simulator fur TCP sources at the general case where the token level cannot stay in demotion region without the prior demotion at the negotiated rate set as the bottleneck link bandwidth. The simulation results demonstrate that through the combined dropper with the newly configured token filling rate, the modified REDP marker also increases both aggregate in-profile throughput and link utilization in addition to TCP fairness improvement compared to the REDP marker.

Buffeting response control of a long span cable-stayed bridge during construction using semi-active tuned liquid column dampers

  • Shum, K.M.;Xu, Y.L.;Guo, W.H.
    • Wind and Structures
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    • v.9 no.4
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    • pp.271-296
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    • 2006
  • The frequency of a traditional tuned liquid column damper (TLCD) depends solely on the length of liquid column, which imposes certain restrictions on its application to long span cable-stayed bridges during construction. The configuration of a cable-stayed bridge varies from different construction stages and so do its natural frequencies. It is thus difficult to apply TLCD with a fixed configuration to the bridge during construction or it is not economical to design a series of TLCD with different liquid lengths to suit for various construction stages. Semi-active tuned liquid column damper (SATLCD) with adaptive frequency tuning capacity is studied in this paper for buffeting response control of a long span cable-stayed bridge during construction. The frequency of SATLCD can be adjusted by active control of air pressures inside the air chamber at the two ends of the container. The performance of SATLCD for suppressing combined lateral and torsional vibration of a real long span cable-stayed bridge during construction stage is numerically investigated using a finite element-based approach. The finite element model of SATLCD is also developed and incorporated into the finite element model of the bridge for predicting buffeting response of the coupled SATLCD-bridge system in the time domain. The investigations show that with a fixed container configuration, the SATLCD with adaptive frequency tuning can effectively reduce buffeting response of the bridge during various construction stages.

Development and Application of a Digital Certificate Classification Framework: A Configuration Perspective (디지털 인증 분류 프레임워크의 개발과 적용: 상황적 관점)

  • Kim, Chang-Su;Gafurov, Dilshodjon
    • Information Systems Review
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    • v.11 no.3
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    • pp.107-123
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    • 2009
  • In this paper, we review digital certificate technologies and their applications in e-commerce. Current digital certificate technologies are evaluated and their importance is explained. The configuration of certificate flows from providers to users through software, hardware, and network technologies is described. These five domains and the configuration of digital certificate flows guide our review of the characteristics of digital certificates. We then develop a framework for the classification of digital certificates that integrate these five domains with VeriSign's types and levels of assurance. In order to demonstrate the adequacy of our digital certificate classification framework, we populated it with VeriSign's digital certificates. Within each domain, VeriSign's classes of digital certificates are classified in accordance with the VeriSign type and level of assurance. The results of our analysis suggest that the framework is a useful step in developing a taxonomy of digital certificate technologies. The strengths and weaknesses of the study are discussed, and opportunities for further research are identified and discussed.

Mechanism Study of dTDP-D-Glucose 4,6-Dehydratase: General Base in Active Site Domain

  • Sohng, Jae-Kyung;Noh, Hyung-Rae;Yoo, Jin-Cheol
    • BMB Reports
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    • v.32 no.4
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    • pp.358-362
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    • 1999
  • dTDP-D-glucose 4,6-dehydratase as an oxidoreductase catalyzes the conversion of dTDP-D-glucose to dTDP-4-keto-6-deoxy-D-glucose, which is essential for the formation of 6-deoxysugars. dTDP-D-glucose 4,6-dehydratase shows remarkable sterochemical convergence in which displacement of the C-6 hydroxyl group by a C-4 hydrogen proceeds intramolecularly with inversion of configuration. The reaction mechanism is known to be oxidation, dehydration, and reduction by bases mediating proton transfer and $NAD^+$ cofactor. In this study, the bases in the active site domain are proposed to be His-79 and His-300 from a comparison of the peptides of the dehydratase and UDP-D-glucose epimerase. His-79 and His-300 were mutated to prepare the mutants H79L (mutation of histidine to leucine at the 79th amino acid) and H300A (mutation of histidine to alanine at the 300th amino acid) by site-directed mutagenesis. The H79L protein was inactive, showing that His-79 participates in the reaction mechanism.

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A Numerical Simulation on the Development of Cloud (적운 발달에 관한 수치 시뮬레이션)

  • Lee, Hwa-Un;Kim, Yu-Geun;Jeon, Byeong-Il
    • Journal of Environmental Science International
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    • v.1 no.2
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    • pp.15-23
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    • 1992
  • Development of cumulus is studied by numerically integrating the equation of motion equations of conservation for water vapor mixing ratio, and the thermodynamic energy equuation. We use the terrain-following coordinate system called z'-coordinate system, in which we can easily treat any calculation domain with terrain configuration such as mountains. The model domain of calculation is restricted vertically to 4.Skin and horizontally to 100 km, has a bell-type mountain in the centeral part. Four cases are considered, one in a neutral environment, second in a slightly stable environment, third in a environment decreasing water content with low value of initial water vapor mixing ratio, the fourth in a case with higher vapor gradient. The more the atmosphere is unstable, the more cumulus develops easily and the more water vapors is abundant, the more cumulus develops easily too. More detailed cloud microphysics parameterizations and wet deposition must be conridered to use in air pollutants prediction model.

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Implementation of QoS Provisioning Model in VANET (VANET에서 QoS Provisioning모델의 구현)

  • Huh, Jee-Wan;Song, Wang-Cheol
    • Proceedings of the Korea Contents Association Conference
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    • 2009.05a
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    • pp.884-888
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    • 2009
  • Vehicular Adhoc Networks (VANET), a Vehicle-to-Infrastucture or Vehicle-to-Vehicle communication technology, is an area that makes more specific use of Mobile Adhoc Networks(MANET). VANET's Quality of Service(QoS) focuses on preventing possible emergencies like car crash from happening by immediately transmitting information to the cars around, while MANET's QoS is being studied for the quality of multimedia data such as Video on Demand(VoD), Video streaming, Voice over IP(VoIP), etc. In this paper, I structure the actual network configuration using Link State Routing(LSR), implement QoS Provisioning Model using Common Open Policy Service(COPS), and suggest more effective k-hop Cluster and inter-domain policy negotiation which fit better to the characteristics of VANET.

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