• 제목/요약/키워드: high-order diffusion

검색결과 358건 처리시간 0.028초

최적화 기법을 이용한 에너지 효율 프로그램의 지원금 수준 산정 (Estimation of Rebate Level for Energy Efficiency Programs Using Optimization Technique)

  • 박종진;소철호;김진오
    • 전기학회논문지
    • /
    • 제57권3호
    • /
    • pp.369-374
    • /
    • 2008
  • This paper presents the evaluation procedures and the estimation method for the estimation of optimal rebate level for EE(Energy Efficiency) programs. The penetration amount of each appliance is estimated by applying price function to preferred diffusion model resulted from model compatibility test. To estimate the optimal rebate level, two objective functions which express the maximum energy saving and operation benefit are introduced and by multi-objective function which can simultaneously consider two objective functions the optimal rebate level of each appliance is estimated. And then, using the decided rebate level and each penetration amount, the priority order for reasonable investment of each high-efficiency appliance is estimated compared to the results of conventional method. Finally, using a benefit/cost analysis based on California standard practice manual, the economic analysis is implemented for the four perspectives such as participant, ratepayer impact measure, program administrator cost and total resource cost.

엑시머 레이져를 이용한 극히 얕은 접합과 소스, 드레인의 형성과 50nm 이하의 극미세 n-MOSFET의 제작 (Ultra Shallow Junction wish Source/Drain Fabricated by Excimer Laser Annealing and realized sub-50nm n-MOSFET)

  • 정은식;배지철;이용재
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2001년도 하계학술대회 논문집
    • /
    • pp.562-565
    • /
    • 2001
  • In this paper, novel device structures in order to realize ultra fast and ultra small silicon devices are investigated using ultra-high vacuum chemical vapor deposition(UHVCVD) and Excimer Laser Annealing (ELA). Based on these fundamental technologies for the deep sub-micron device, high speed and low power devices can be fabricated. These junction formation technologies based on damage-free process for replacing of low energy ion implantation involve solid phase diffusion and vapor phase diffusion. As a result, ultra shallow junction depths by ELA are analyzed to 10~20nm for arsenic dosage(2${\times}$10$\_$14//$\textrm{cm}^2$), exciter laser source(λ=248nm) is KrF, and sheet resistances are measured to 1k$\Omega$/$\square$ at junction depth of 15nm and realized sub-50nm n-MOSFET.

  • PDF

Stationary bootstrap test for jumps in high-frequency financial asset data

  • Hwang, Eunju;Shin, Dong Wan
    • Communications for Statistical Applications and Methods
    • /
    • 제23권2호
    • /
    • pp.163-177
    • /
    • 2016
  • We consider a jump diffusion process for high-frequency financial asset data. We apply the stationary bootstrapping to construct a bootstrap test for jumps. First-order asymptotic validity is established for the stationary bootstrapping of the jump ratio test under the null hypothesis of no jump. Consistency of the stationary bootstrap test is proved under the alternative of jumps. A Monte-Carlo experiment shows the advantage of a stationary bootstrapping test over the test based on the normal asymptotic theory. The proposed bootstrap test is applied to construct continuous-jump decomposition of the daily realized variance of the KOSPI for the year 2008 of the world-wide financial crisis.

고효율기기의 보급확산을 고려한 전력수요관리 모니터링시스템의 방법론 개발 (Development of DSM(Demand Side Management) Monitoring Methodology Considering the Diffusion Process of High Efficient End-Use Appliances)

  • 황성욱;김발호;김정훈;장승찬;김창섭
    • 대한전기학회논문지:전력기술부문A
    • /
    • 제48권8호
    • /
    • pp.941-950
    • /
    • 1999
  • This paper presents a DSM monitoring methodology that is able to evaluate the impact of DSM programs especially focused on the strategic conservation i.e. the enhancement of end-use energy efficiency. For an effective assessment of DSM programs, it is foremost necessary to examine the market characteristics on the specific end-use appliance according to the customer's adoption of DSM programs. The proposed monitoring methodology contains a diffusion process of high efficient end-uses considering major factors of DSM impact such as, price, reference capacity, forecasted capacity and lifetime of end-use appliances. Case studies show the projection of power reductions and energy savings resulted from DSM monitoring in order to diagnose the current status properly and provide a baseline of DSM policy and analysis.

  • PDF

NUMERICAL SOLUTIONS FOR SPACE FRACTIONAL DISPERSION EQUATIONS WITH NONLINEAR SOURCE TERMS

  • Choi, Hong-Won;Chung, Sang-Kwon;Lee, Yoon-Ju
    • 대한수학회보
    • /
    • 제47권6호
    • /
    • pp.1225-1234
    • /
    • 2010
  • Numerical solutions for the fractional differential dispersion equations with nonlinear forcing terms are considered. The backward Euler finite difference scheme is applied in order to obtain numerical solutions for the equation. Existence and stability of the approximate solutions are carried out by using the right shifted Grunwald formula for the fractional derivative term in the spatial direction. Error estimate of order $O({\Delta}x+{\Delta}t)$ is obtained in the discrete $L_2$ norm. The method is applied to a linear fractional dispersion equations in order to see the theoretical order of convergence. Numerical results for a nonlinear problem show that the numerical solution approach the solution of classical diffusion equation as fractional order approaches 2.

고속카메라를 이용한 디젤엔진내의 화염 가시화, 화염의 온도 및 매연 측정에 관한 연구 (A Study on the Measurement of Flame Visualization, Temperature and Soot for Diffusion Flame in a Diesel Engine Using High-Speed Camera)

  • 한용택;이기형
    • 대한기계학회논문집B
    • /
    • 제31권2호
    • /
    • pp.132-140
    • /
    • 2007
  • The temperature and soot of the visualized diesel engine's turbulent flow of the flame was measured qualitatively. In the combustion chamber, in order to judge the affect that the swirl current has on the current ratio two heads with different ratios were used. Using a high speed camera, the results were analyzed using flame visualization. In order to measure the temperature and soot of the turbulent flames like diesel flames, two color methods were used to acquire temperature and the soot of the flames according to the conditions through analyzing the two wavelengths of the flames. It was possible to measure the highest temperature of the non-swirl head visualized engine, which is approximately 2400K, and that swirl head engine managed up to 2100K. With respect to the visualized diesel engine soot, we got the grasp of the KL factor which bears the qualitative information of the soot. This study is dedicated to suggesting the possibility of measuring not only the temperature but also soot of the diffusion flame of the diesel engine turbulent flames.

나노크기 실리카를 사용한 반도체용 액상 에폭시 수지 성형재료의 흡습성질 (Moisture Absorption Properties of Liquid Type Epoxy Encapsulant with Nano-size Silica for Semiconductor Packaging Materials)

  • 김환건
    • 반도체디스플레이기술학회지
    • /
    • 제9권2호
    • /
    • pp.33-39
    • /
    • 2010
  • The moisture absorption properties such as diffusion coefficient and moisture content ratio of liquid type epoxy resin systems with the filler were investigated. Bisphenol A type and Bisphenol F type epoxy resin, Kayahard MCD as hardener and 2-methylimidazole as catalyst were used in these epoxy resin systems. The nano-sized spherical type fused silica as filler were used in order to study the moisture absorption properties of these liquid type epoxy encapsulant according to the change of filler size. The temperature of glass transition (Tg) of these epoxy resin systems was measured using Dynamic Scanning Calorimeter (DSC), and the moisture absorption properties of these epoxy resin systems according to the change of time were observed at $85^{\circ}C$ and 85% relative humidity condition using a thermo-hygrostat. The diffusion coefficients in these systems were calculated in terms of modified Crank equation based on Ficks' law. An increase of Tg and diffusion coefficient with filler size in these systems can be observed, which are attributed to the increase of free volume with Tg. The change of maximum moisture absorption ratio according to the filler size and filler content cannot be observed; however, the diffusion coefficients of these systems decreased with filler content. The diffusion via free volume is dominant in the epoxy resin systems with low nano-sized filler content; however, the diffusion with the interaction of absorption according the increase of the filler surface area is dominant in the liquid type epoxy encapsulant with high nano-sized filler content.

선단과냉을 고려한 이원합금의 주상 수지상응고 모델 (A model for columnar-dendritic solidification of binary alloys accounting for dendrite tip undercooling)

  • 유호선
    • 대한기계학회논문집B
    • /
    • 제22권5호
    • /
    • pp.698-707
    • /
    • 1998
  • A simplified model for predicting microsegregation during columnar-dendritic solidification of binary alloys is developed, in which back diffusion, dendrite arm coarsening and dendrite tip undercooling are simultaneously incorporated. The inclusion of tip undercooling is accomplished by modifying the initial conditions of the existing solute diffusion model, in such forms that tip undercooling depresses the beginning of solidification below the liquidus temperature, and that the secondary arm spacing evolves in accordance with the minimum undercooling theory. Sample calculations for the well-known benchmark system show that the present predictions not only consist with the extablished limiting cases, but also agree favorably with the available experimental data within a reasonable tolerance. In particular, a typical decreasing trend in the eutectic fraction at high cooling rates is successfully resolved. Comparison of the individual and combined effects of characteristic parameters in reference with the limiting cases reveals the interactions among parameters. Every parameter plays the role of reducing the eutectic fraction, and the degree of influence depends primarily on the cooling rate. Coarsening enhances the effect of tip undercooling, while suppressing that of back diffusion. A vigorous back diffusion seems to restrain the apperance of the undercooling effect. Overall, each contribution of the three parameters to microsegregation is estimated to be of the same order, which suffices to justify the present study.

동전기 주입에 의한 점성토의 강도증가 특성 (Characteristic of Strength Increase in Clayey Soil by Electrokinetic Injection)

  • 김기년;김종윤;한상재;김수삼
    • 한국지반공학회:학술대회논문집
    • /
    • 한국지반공학회 2005년도 춘계 학술발표회 논문집
    • /
    • pp.910-915
    • /
    • 2005
  • In this study a series of tests(bench scale test) are carried out for increasing in strength of clayey soil by EK-Injection method. In addition, the effects of strength increase in the treated sample are measured by operating the vane shear test device during 25 days at 5 days intervals in order to estimate the effect of ground improvement caused by diffusion. The test results show that the strength increase was developed approximately double to 7 times in comparison to initial shear strength, and outstanding strength increase was created as much as 7 times while injecting the sodium silicate and phosphoric acid in anolyte and catholyte. In addition, the measured shear strength with the influence of diffusion and reduction of water-content had a tendency to converge in constant value in proportion to elapsed time. As a result of this study, strength increment developed by the influence of EK-Injection and diffusion rather than the reduction of water-content were high as 1000% on average

  • PDF

제트 확산화염의 연소특성과 매연생성에 관한 연구 (Combustion Characteristics and Soot Formation in a Jet Diffusion Flame)

  • 이교우;백승욱
    • 대한기계학회논문집
    • /
    • 제18권10호
    • /
    • pp.2712-2723
    • /
    • 1994
  • Numerical simulation of an axisymmetric ethylene-air jet diffusion flame has been carried out in order to investigate flame dynamics and soot formation. The model solves the time-dependent Navier-Stokes equations and includes models for soot formation, chemical reaction, molecular diffusion, thermal conduction, and radiation. Numerically FCT(Flux Corrected Transport) and DOM(Discrete Ordinate Method) methos are used for convection and radiation trasport respectively. Simulation was conducted for a 5 cm/sec fuel jet flowing into a coflowing air stream. The maximum flame temperature was found to be approximately 2100 K, and was located at an axial position of approximately 5 cm from the base of the flame. The maximum soot volume fraction was about $7{\times}10^{-7}$, and was located within the high temperature region where the fuel mole fraction ranges from 0.01 to 0.1. The buoyancy-driven low-frequency(12~13 Hz) structures convected along the outer region of the flame were captured. In case without radiation trasport, the maximum temperature was higher by 150 K than in case with radiation. Also the maximum soot volume fraction reached about $8{\times}10^{-6}$. As the the hydrocarbon fuel forms many soot particles, the radiation transport becomes to play a more important role.