• Title/Summary/Keyword: modular function

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TCP의 자기 유사성 트래픽 조건하에서 다중 시간 간격을 이용한 혼잡 제어 (The Congestion Control using Multiple Time Scale under Self-Similar Traffic of TCP)

  • 김광준;윤찬호;김천석
    • 한국정보통신학회논문지
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    • 제8권2호
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    • pp.310-323
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    • 2004
  • In this paper, we extend the multiple time scale control framework to window-based congestion control, in particular, TCP This is performed by interfacing TCP with a large tine scale control nodule which adjusts the aggressiveness of bandwidth consumption behavior exhibited by TCP as a function of "large time scale" network state. i.e., conformation that exceeds the horizon of the feedback loop as determined by RTT Our contribution is threefold. First, we define a modular extension of TCP-a function call with a simple interface-that applies to various flavors of TCP-e.g., Tahoe, Reno, Vegas and show that it significantly improves performance. Second, we show that multiple time scale TCP endows the underlying feedback control with preactivity by bridging the uncertainty gap associated with reactive controls which is exacerbated by the high delay-bandwidth product in broadband wide area networks. Third, we investigate the influence of three traffic control dimensions-tracking ability, connection duration, and fairness-on performance. Performance evaluation of multiple time scale TCP is facilitated by a simulation bench-mark environment which is based on physical modeling of self-similar traffic.

Okamoto-Uchiyama 확률 공개키 암호 방식의 효율성 개선 (Improvement of Okamoto-Uchiyama Probabilistic Public Key Cryptosystem)

  • 최덕환;김현주;최승복;원동호
    • 한국정보과학회논문지:정보통신
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    • 제29권4호
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    • pp.346-351
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    • 2002
  • 본 논문은 Okamoto와 Uchiyama가 이산대수 함수만으로 일방향함수를 정의하여 제안한 새로운 확률 공개키 암호 방식을 개선하였다. 평문은 이들 두 이산대수 함수의 모듈라 곱으로부터 구할 수 있는데 두 함수 값 중에서 하나는 주어진 공개키에 종속된 고정된 값을 가진다. 고정된 함수 값이 단위원 1을 갖는 정선된 공개키에 의해 개선이 이루어진다. 왜냐하면 복호화 할 때 계산량을 줄일 수 있기 때문이다. 또한 이러한 성질을 충족하는 공개키를 얻을 수 있는 구체적 방법도 제시한다.

An Advanced Simulation Model for Brushless DC Motor Drives

  • Lee B. K.;Ehsani M.
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2001년도 Proceedings ICPE 01 2001 International Conference on Power Electronics
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    • pp.390-394
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    • 2001
  • A dynamic simulation model for the brush less dc (BLDC) motor drives using Matlab is presented. In this model, an entire BLDC motor drive, including power conversion unit, BLDC motor, and speed/torque control system, is investigated. Especially, the PWM inverter is modeled using switching function concept, so that the detailed voltage and current waveforms, such as line-to-line voltages, inverter input current, ac line current, and switch/diode currents, can be obtained and average/rms ratings of the components can be easily calculated. Also, the proposed model is made into modular blocks and it can be easily extended to other ac motor applications with a little modification. The detailed modeling method is explained and its actual implementation is described. The validity of the proposed model is verified by various simulation results.

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일 대학병원 간호직원 근무 스케쥴링 전산화 개발 사례 (A Development of Decision Support System for Nurse Scheduling)

  • 최용선;이은숙;박정호
    • 대한간호학회지
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    • 제25권1호
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    • pp.80-87
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    • 1995
  • The critical problem of nurse scheduling in the hospital is determining the day-to -day shift assignments for each nurse for the specified period in a way that satisfies the given requirements of the hospital. As nurse scheduling involves many factors and requirements, manual scheduling requires much time and effort to produce an adequate schedule. A PC - based decision support system, developed in Turbo - C/sup ++/, for nurse scheduling was introduced. The system is composed of 4 sub-systems : 1) Entering basic information for each nursing unit : 2) Generation of an appropriate initial schedule and revised schedule for a given period, maximally satisfying each nurse's duty requests : 3) Provision of variety of statistical information, and 4) Help messages for each modular function. Icons and a mouse are used for easier graphic user interface and reducing the need for typing efforts. This system can help nurses develop quick and easy schedule generation and allow more time for the patient care.

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A NOTE ON THE θ3(0, τ)

  • Kim, Daeyeoul;Jeon, Hyeong-Gon
    • Korean Journal of Mathematics
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    • 제6권1호
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    • pp.67-70
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    • 1998
  • Let ${\eta}(\tau)=q^{1/24}\prod_{n=1}^{\infty}(1-q^n)$, where $q=e^{2{\pi}i{\tau}}$ and ${\tau}{\in}\mathbb{C}$. Then the transformation $$g(\tau)={\rho}\frac{\{\eta(\frac{\tau+1}{2})\eta(\frac{\tau+2}{2})\}^{16}}{\eta(\tau)^{24}}({\bar{{\rho}}{\eta}}(\frac{\tau+1}{2})^8+{\eta}(\frac{\tau+2}{2})^8)^2$$ is holomorphic for Im ${\tau}$ > 0, and has the property $$g(\tau+1)=g(\tau),\;g(-\frac{1}{\tau})={\tau}^{12}g(\tau)$$. (Theorem)

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Ω-RESULT ON COEFFICIENTS OF AUTOMORPHIC L-FUNCTIONS OVER SPARSE SEQUENCES

  • LAO, HUIXUE;WEI, HONGBIN
    • 대한수학회지
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    • 제52권5호
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    • pp.945-954
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    • 2015
  • Let ${\lambda}_f(n)$ denote the n-th normalized Fourier coefficient of a primitive holomorphic form f for the full modular group ${\Gamma}=SL_2({\mathbb{Z}})$. In this paper, we are concerned with ${\Omega}$-result on the summatory function ${\sum}_{n{\leqslant}x}{\lambda}^2_f(n^2)$, and establish the following result ${\sum}_{\leqslant}{\lambda}^2_f(n^2)=c_1x+{\Omega}(x^{\frac{4}{9}})$, where $c_1$ is a suitable constant.

디지털기술과 산업 전환 : 전자산업의 사례

  • 배영자
    • 기술혁신연구
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    • 제11권2호
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    • pp.219-238
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    • 2003
  • This study aims to investigate the impact of wide use of digital technology, in particular, the Internet, on innovation process and corporate strategy in electronics industry. The introduction of digital technology has changed innovation process, business model and organizational structure of the electronics companies. With the wide use of digital technology, the entire value chain of electronics industry from procurement, sales, and marketing to R&D and manufacturing has been restructured. This paper examine how digital technology has changed firms' behaviors in various areas through e-commerce, virtual reality and simulation, the rise of a new type of firm called EMS (Electronics Manufacturing Services), and etc. Amidst these changes building up innovation-friendly organization has emerged as a critical concern for firms. Due to the striking decrease of transaction cost, a network type of organization has proliferated, and a business function turns into a modular organization. As a whole, digital technology has pushed electronics firms into developing their own business model, which takes consideration of standardization of business platform and their core competency.

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Role of the CCN protein family in cancer

  • Kim, Hyungjoo;Son, Seogho;Shin, Incheol
    • BMB Reports
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    • 제51권10호
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    • pp.486-492
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    • 2018
  • The CCN protein family is composed of six matricellular proteins, which serve regulatory roles rather than structural roles in the extracellular matrix. First identified as secreted proteins which are induced by oncogenes, the acronym CCN came from the names of the first three members: CYR61, CTGF, and NOV. All six members of the CCN family consist of four cysteine-rich modular domains. CCN proteins are known to regulate cell adhesion, proliferation, differentiation, and apoptosis. In addition, CCN proteins are associated with cardiovascular and skeletal development, injury repair, inflammation, and cancer. They function either through binding to integrin receptors or by regulating the expression and activity of growth factors and cytokines. Given their diverse roles related to the pathology of certain diseases such as fibrosis, arthritis, atherosclerosis, diabetic nephropathy, retinopathy, and cancer, there are many emerging studies targeting CCN protein signaling pathways in attempts to elucidate their potentials as therapeutic targets.

반응면기법을 이용한 PBMR 기체냉각형 고온가스로 상층부의 최적설계 (DESIGN OPTIMIZATION OF UPPER PLENUM OF PBMR USING RESPONSE SURFACE APPROXIMATION)

  • 이상문;김광용
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2010년 춘계학술대회논문집
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    • pp.187-194
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    • 2010
  • Shape optimization of an upper plenum of PBMR type gas cooled nuclear reactor has been performed by using three-dimensional Reynolds-Averaged Navier-Stokes (RANS) analysis and surrogate modeling technique. The objective function is defined as a linear combination of uniformity of flow distribution in the core and pressure drop in the upper plenum and the core. The ratio of thickness of slot to diameter of rising channels, ratio of height of upper plenum to diameter of rising channels, and ratio of eight of the slot at inlet to outlet, are used as design variables for optimization. Design points are selected through Latin-hypercube sampling. The optimal point is determined through surrogate-based optimization method which uses 3-D RANS analyses at design points. The results show that the optimum shape represent remarkably improved performance in flow uniformity and friction loss than the reference shape.

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반응면기법을 이용한 PBMR 기체냉각형 고온가스로 상층부의 최적설계 (DESIGN OPTIMIZATION OF UPPER PLENUM OF PBMR USING RESPONSE SURFACE APPROXIMATION)

  • 이상문;김광용
    • 한국전산유체공학회지
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    • 제15권3호
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    • pp.16-23
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    • 2010
  • Shape optimization of an upper plenum of a PBMR type gas cooled nuclear reactor has been performed by using three-dimensional Reynolds-Averaged Navier-Stokes (RANS) analysis and surrogate modeling technique. The objective function is defined as a linear combination of uniformity of flow distribution in the core and pressure drop in the upper plenum and the core. The ratio of thickness of slot to diameter of rising channels, ratio of height of upper plenum to diameter of rising channels, and ratio of height of the slot at inlet to outlet, are used as design variables for optimization. Design points are selected through Latin-hypercube sampling. The optimal point is determined through surrogate-based optimization method which uses 3-D RANS analyses at design points. The results show that the optimum shape represent remarkably improved performance in flow uniformity and friction loss than the reference shape.