• 제목/요약/키워드: W-function

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78K에서 수소 혹은 중수소 흡착으로 인한 W(123)면의 일함수 변화 (Work Function Change of W(123) Plane Due to Hydrogen and Deuterium Adsorption at 78K)

  • 박노길;김기석;김성수;정광호;황정남;최대선
    • 한국진공학회지
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    • 제1권1호
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    • pp.78-82
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    • 1992
  • W(123) 표면위에 수소와 중소수가 흡착될 때 일함수의 변화를 장방출(Field Fmission) 방법으로 측정하였다. 78K에서 이 분자들이 흡착될 때 일함수의 변화는 처음에 는 증가하다가 최대치에 이른 후 감소하였고, 덮임율(coverage)이 증가함에 따라 포화되었 다. 텅스텐 tip의 온도를 200K까지 올렸을 경우에, 일함수의 변화가 최대가 되었을 때의 덮 임율은 78K일 때의 비해 낮은 덮임율 쪽으로 이동하였고, [011] 방향을 갖는 step 혹은 terrace에 의한 일함수의 효과도 동시에 관측되었다.

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소프트웨어 신뢰도의 적정 파라미터 도출 기법에 관한 연구 (A Study on the Optimum Parameter Estimation of Software Reliability)

  • 최규식;문명호
    • Journal of Information Technology Applications and Management
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    • 제13권4호
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    • pp.1-12
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    • 2006
  • Many software reliability growth models(SRGM) have been proposed since the software reliability issue was raised in 1972. The technology to estimate and grow the reliability of developing S/W to target value during testing phase were developed using them. Most of these propositions assumed the S/W debugging testing efforts be constant or even did not consider them. A few papers were presented as the software reliability evaluation considering the testing effort was important afterwards. The testing effort forms which have been presented by this kind of papers were exponential, Rayleigh, Weibull, or logistic functions, and one of these 4 types was used as a testing effort function depending on the S/W developing circumstances. I propose the methology to evaluate the SRGM using least square estimator and maximum likelihood estimator for those 4 functions, and then examine parameters applying actual data adopted from real field test of developing S/W.

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램버트 W 함수를 사용한 라플라스 신호의 최소 평균제곱오차 양자화 (The Lambert W Function in the Design of Minimum Mean Square-Error Quantizers for a Laplacian Source)

  • 송현정;나상신
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 하계종합학술대회 논문집(1)
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    • pp.333-336
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    • 2001
  • This paper reports that the Lambert W function applies to a non-iterative design of minimum mean square-error scalar quantizers for a Laplacian source. The contribution of the paper is in the reduction of the time needed for the design and the increased accuracy in resulting quantization points and thresholds, because the algorithm is non-iterative and the Lambert W function can be evaluated as accurately as desired.

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Lambert W 함수를 이용한 태양전지 모델링 (The solar cell modeling using Lambert W-function)

  • 배종국;강기환;김경수;유권종;안형근;한득영
    • 한국태양에너지학회:학술대회논문집
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    • 한국태양에너지학회 2011년도 추계학술발표대회 논문집
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    • pp.278-281
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    • 2011
  • This system can predict the maximum output about all illumination levels so that the PV system designer can design the system having the best efficiency. For the output prediction exact about the solar cell, that is the device the basis most in the PV system, the basis has to be in order to try this way. The solution based on Lambert W-function are presented to express the transcendental current-voltage characteristic containing parasitic power consuming parameters like series and shunt resistances. A simple and efficient method for the extraction of a single current-voltage (I-V) curve under the constant illumination level is proposed. With the help of the Lambert W function, the explicit analytic expression for I is obtained. And the explicit analytic expression for V is obtained. This analytic expression is directly used to fit the experimental data and extract the device parameters. The I-V curve of the solar cell was expressed through the modeling using Lambert W-function and the numerical formula where there is the difficulty could be logarithmically expressed This method expresses with the I-V curve through the modeling using Lambert W-function which adds other loss ingredients to the equation2 as to the research afterward. And the solar cell goes as small and this I-V curve can predict the power penalty in the system unit.

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ANALYSIS ON THE AVAILABILITY OF COMS GS

  • Park, Durk-Jong;Lim, Hyun-Su;Ahn, Sang-Il
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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    • pp.212-215
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    • 2006
  • This paper describes several reliability models to estimate COMS ground segment availability and shows assessed availability according to GS function. Due to a back-up concept among three ground center, SOC will have all H/W and S/W module to be installed in MSC and KOSC site. Therefore, all configurations and availability parameters for H/W and S/W modules in MSC and KOSC are assumed as equal with those in SOC, if related modules have same function. Prior to access availability over COMS GS function, Availability related to fundamental configuration such as series, parallel, partial operation, and module combined H/W and S/W is described. Consequently, all functions are expected to operate with more than 99% of availability.

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수소 Plasma 처리 후의 MgO 보호막에 대한 일함수 변화 측정 (Measurement of Changes in Work Function on MgO Protective Layer after H2-plasma Treatment)

  • 정재천;이석주;조재원
    • 한국전기전자재료학회논문지
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    • 제20권7호
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    • pp.611-614
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    • 2007
  • The changes in the work $function({\Phi}_w)$ in the MgO protective layers after $plasma(Ar,\;H_2)$ treatment have been studied using ${\Upsilon}-focused$ ion beam $({\Upsilon}-FIB)$ system. The ${\Phi}_w$ was determined as follows: Ar-plasma $treatment({\Phi}_w=4.52eV)$, $H_2-plasma$ $treatment({\Phi}_w=5.65eV)$, and non-plasma $treatment({\Phi}_w=4.64eV)$. The results indicated that the H-plasma could not make any effective physical etching due to the small masses of hydrogen atoms and molecules while the hydration of H-plasma could grow some contaminating materials on the surface of MgO.

COEFFICIENT ESTIMATES FOR FUNCTIONS ASSOCIATED WITH VERTICAL STRIP DOMAIN

  • Bulut, Serap
    • 대한수학회논문집
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    • 제37권2호
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    • pp.537-549
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    • 2022
  • In this paper, we consider a convex univalent function fα,β which maps the open unit disc 𝕌 onto the vertical strip domain Ωα,β = {w ∈ ℂ : α < ℜ < (w) < β} and introduce new subclasses of both close-to-convex and bi-close-to-convex functions with respect to an odd starlike function associated with Ωα,β. Also, we investigate the Fekete-Szegö type coefficient bounds for functions belonging to these classes.

제조공정 Network의 개선을 위한 W-함수 (W-function for the Improvement of the Network in Manufacturing Process)

  • 이상도;박기주
    • 산업경영시스템학회지
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    • 제12권20호
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    • pp.71-76
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    • 1989
  • In this paper, GERT network in modeled to improve the network of manufacturing process with feedback loop. A lot of Information on the GERT network can be derived from the equivalent W-function and MGF(moment generating function) using Mason's rule. These equations are used in calculating the variations of the performance measure and in improving the system performance. System improvement in manufacturing process is achieved by increasing the equivalent probabilities of each branches and by decreasing the expected equivalent time.

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STABILITY OF THE BERGMAN KERNEL FUNCTION ON PSEUDOCONVEX DOMAINS IN $C^n$

  • Cho, Hong-Rae
    • 대한수학회논문집
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    • 제10권2호
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    • pp.349-355
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    • 1995
  • Let $D \subset C^n$ be a smoothly bounded pseudoconvex domain and let ${\bar{D}_r}_r$ be a family of smooth perturbations of $\bar{D}$ such that $\bar{D} \subset \bar{D}_r$. Let $K_D(z, w)$ be the Bergman kernel function on $D \times D$. Then $lim_{r \to 0} K_{D_r}(z, w) = K_D(z, w)$ locally uniformally on $D \times D$.

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마이데이터 API G/W 설계 연구 (A Study On the Design of MyData API G/W)

  • 독고세준;최창원
    • 사물인터넷융복합논문지
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    • 제9권2호
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    • pp.47-54
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    • 2023
  • 마이데이터 서비스를 이용하여 정보 주체인 개인이 본인의 정보를 적극적으로 관리 및 통제하여 이를 신용관리, 자산 관리 등에 능동적으로 활용할 수 있다. 마이데이터는 기업과 기관 중심의 개인 데이터 생태계를 데이터의 주인인 개인에게 자신의 데이터를 통제하고 관리하여 활용할 수 있는 권한을 부여하는 것이다. 마이데이터 서비스를 성공적으로 제공하기 위해서는 다양한 기관에서 제공되는 서로 다른 형식의 데이터를 표준 규격 형태로 변환하기 위한 API G/W의 개발이 필수적인 요소이다. 본 논문에서는 마이데이타 서비스의 API G/W 개발을 위해 검증(Validation) 기능, 관리(Throttling) 기능, 인증 및 권한(Authentication & Authorization) 기능, 중재(Mediation) 기능으로 주요 기능들을 도출하고 각 세부 기능별로 해당 서비스를 설계하였다. 설계된 API G/W의 기능들을 통해 다양한 형식의 요구들을 서비스할 수 있는 마이데이터 서비스를 안전하고 효율적으로 지원할 수 있었다.