• 제목/요약/키워드: ExpGA

검색결과 14건 처리시간 0.021초

유전자 알고리듬을 이용할 대량의 설계변수를 가지는 문제의 최적화에 관한 연구 (A Study of A Design Optimization Problem with Many Design Variables Using Genetic Algorithm)

  • 이원창;성활경
    • 한국정밀공학회지
    • /
    • 제20권11호
    • /
    • pp.117-126
    • /
    • 2003
  • GA(genetic algorithm) has a powerful searching ability and is comparatively easy to use and to apply as well. By that reason, GA is in the spotlight these days as an optimization skill for mechanical systems.$^1$However, GA has a low efficiency caused by a huge amount of repetitive computation and an inefficiency that GA meanders near the optimum. It also can be shown a phenomenon such as genetic drifting which converges to a wrong solution.$^{8}$ These defects are the reasons why GA is not widdy applied to real world problems. However, the low efficiency problem and the meandering problem of GA can be overcomed by introducing parallel computation$^{7}$ and gray code$^4$, respectively. Standard GA(SGA)$^{9}$ works fine on small to medium scale problems. However, SGA done not work well for large-scale problems. Large-scale problems with more than 500-bit of sere's have never been tested and published in papers. In the result of using the SGA, the powerful searching ability of SGA doesn't have no effect on optimizing the problem that has 96 design valuables and 1536 bits of gene's length. So it converges to a solution which is not considered as a global optimum. Therefore, this study proposes ExpGA(experience GA) which is a new genetic algorithm made by applying a new probability parameter called by the experience value. Furthermore, this study finds the solution throughout the whole field searching, with applying ExpGA which is a optimization technique for the structure having genetic drifting by the standard GA and not making a optimization close to the best fitted value. In addition to them, this study also makes a research about the possibility of GA as a optimization technique of large-scale design variable problems.

Anti-inflammatory effects of Agar free-Gelidium amansii (GA) extracts in high-fat diet-induced obese mice

  • Lee, Yunkyoung;Oh, Hyunhee;Lee, Myoungsook
    • Nutrition Research and Practice
    • /
    • 제12권6호
    • /
    • pp.479-485
    • /
    • 2018
  • BACKGROUND/OBJECTIVES: Gelidium amansii (GA) contains plenty of agars and various biological substances, which make them a popular functional food to control body weight in previous studies. Unlike previous studies focused on agar in GA, objectives of this study were to investigate the effects of agar-free GA extract (AfGAE) on preventive and treatment models by using diets-induced obese (DIO) C57BL/6J mice. MATERIALS/METHODS: AfGAE were used to test their effects on the prevention (Exp-1) and treatment (Exp-2) against obesity after pilot study in DIO mice. The weight changes of the body and fat tissues and protein expression related to lipid metabolism and inflammation as well as plasma lipid profile and insulin were detected. RESULTS: Although AfGAE did not prevent long-term DIO, it did increase the levels of anti-inflammatory cytokine production and lipolysis protein. We further evaluated various doses of AfGAE in preventive and treatment models. As a result, our findings suggested that an AfGAE administration as a preventive model might be a better approach to achieve its anti-inflammatory and lipolysis-promoting effects in DIO mice. CONCLUSION: Although future studies to investigate the target materials such as polyphenols in AfGAE are required, the result suggests that GA without agar might be a therapeutic tool to improve health conditions related to inflammation.

Sulfur를 첨가한 $In_{1-x}Ga_xP$의 발광 다이오드 특성 (The characteristics of the sulfur-doped $In_{1-x}Ga_xP$ Light emitting diode)

  • 조명환;문동찬;김선태
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1988년도 추계학술대회 논문집 학회본부
    • /
    • pp.168-171
    • /
    • 1988
  • The p-n homo junction diode of the III-V ternary alloy semiconductor $In_{1-x}Ga_xP$ : S grown by the temperature gradient solution (TGS) was fabricated by Zn-diffusion, and it's characteristics was investigated. The carrier concentration of $In_{1-x}Ga_xP$ doped with sulfur, 0.5 mol %, was $1{\times}10^{17}cm^{-3}$ and the mobility was varied with the composition. In the case that the diffusion time was constant as 30 minutes. The temperature dependence of diffusion coefficient was decreased from D= $4.2{\times}10^{-5}$ exp (-1.74/$k_{B}T$) to D= $2.5{\times}10^{-5}$ exp (-3.272/$k_{B}T$) with increasing of composition $\times$ from 0.43 to 0.98. The major peak of E.L spectrum was due to D-A pair recombination and the peak intensity was increased with the increasing of input current. And the E.L intensity was decreased with the increasing temperature, and shift to the long wavelength. The luminescence efficiencies measured at $5^{\circ}C$, atmosphere temperature, was decreased from $2.6{\times}10^{-4}$% to $9.49{\times}10^{-6}$ % with increasing of composition it from 0.39, direct transition region, to 0.98, indirect transition region.

  • PDF

D-Galactosamine으로 유발된 흰쥐의 간손상에 대한 치자두시탕 추출액이 미치는 영향 (Effect of the Chizadochi-Tang on Hepatotoxicity of D-Galactosamine in Rats)

  • 김진호;정종길
    • 대한본초학회지
    • /
    • 제28권2호
    • /
    • pp.17-23
    • /
    • 2013
  • Objectives : To investigate the hepatoprotective effect of Gardeniae Fructus (Ga) and Glycine semen preparatum (Gl) aqueous extract against D-galactosamine (D-GalN, 300mg/kg body weight) was administered to the male Sprague Dawley (SD) rats. Materials and Methods : The study was carried out on male SD rats (age matched, weight $250{\pm}10$ g). Experimental groups (Exp) divided four : Normal group (Nor) was administered saline, Control (Con) group was only received D-GalN (300 mg/kg) intraperitoneally. Exp was orally administered Ga (200 mg/kg; Ga group), Gl (700 mg/kg; Gl group), and Chizadochi-Tang (200 mg/kg+700 mg/kg, GG group) after D-GalN treatment during 14 days (n=6). Results : D-GalN administration induced hepatotoxicity in rats which was manifested by increased levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) but decreased total cholesterol (HDL C) and triglyceride (TG). The serum TG concentrations were significantly increased ($^{\sharp}p$ <0.05) in the Ga group compared with Con. AST and ALP activities were significantly decreased ($^{\sharp}p$ <0.05) in the all experimental groups compared with Con. ALT activities were significantly decreased ($^{\sharp}p$ <0.05) in the Ga group compared with Con. LDH activities were significantly decreased ($^{\sharp}p$ <0.05) in the GG group compared with Con. On the light microscopic study, a number of vacuole were observed in the Con, but decreased in experimental groups. Conclusion : Ga aqueous extract and Chizadochi-Tang extract possesses hepatoprotective potential, thus validating its use in alleviating toxic effects of D-GalN.

Open-Tube에서 Zn확산을 이용한 GaAs에의 $p^+$층 형성 (Formation of $P^+-Layer$ in GaAs Using the Open-Tube Diffusion of Zn)

  • 심규환;강진영;민석기;한철원;최인훈
    • 대한전자공학회논문지
    • /
    • 제25권8호
    • /
    • pp.959-965
    • /
    • 1988
  • Zinc diffusion characteristics and its applicabilities have been studied using an open-tube system. Thermal decomposition of arsenide(As) at gallium arsenide(GaAs) wafer surface was well inhibited by using Ga: poly-GaAs: Zn compositon as a diffusion source. Junction depth was obtained as 4.6x10**7\ulcorner exp)-1.25/kT) where activation energy of diffusion was 1.25eV. From Boltzmann-matano analysis, it could be identified that concentration dependencies of Zn diffusivity well consisted with those of kick-out model. The ideality factor of p+-n junction formed by Zn diffusion was about 1.6 and infrared light intensity was linearly varied in the range of sixty folds. It is concluded frodm these results that Zn diffuses according to kick-out model, and open-tube method is applicable to compound semiconductor devices.

  • PDF

$In_{1-x}Ga_{x}p$ 내에서 Zn 의 확산성질 (The Properties of Zn-diffusion in $In_{1-x}Ga_{x}p$.)

  • 김선태;문동찬;서영석
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1988년도 전기.전자공학 학술대회 논문집
    • /
    • pp.353-355
    • /
    • 1988
  • The properites of Zn-diffusion in III-V ternary alloy semiconductor $In_{1-x}Ga_{x}p$, which was grown by the temperature gradient solution (TGS) method, have been investigated. The composition, x, dependence of the Zn-diffusion coefficient at $850^{\circ}C$ and the activation energy for Zn-diffusion into $In_{1-x}Ga_{x}p$ were found to be $D850^{\circ}C$(x)= $3.935{\times}10^{-8}exp(-6.84{\cdot}x)$, and $E_{A}(x)=1,28+2,38{\cdot}x$, respectively. From this study, we confirm that the Zn-diffusion in $In_{1-x}Ga_{x}p$ was explainable with the diffusion mechanisms of the interstitial-substitutional, which was widely accepted mechanisms in the III-V binary semiconductors.

  • PDF

합성 용질 확산법에 의한 GaAs결정 성장에 관하여 (Growth of GaAs Crystals by synthesis Solute Diffusion Method)

  • 문동찬;정홍배;이영희;김선태;최영복
    • 대한전기학회논문지
    • /
    • 제41권1호
    • /
    • pp.56-62
    • /
    • 1992
  • The GaAs bulk crystals are grown by the Synthesis Solute Diffusion(SSD) method and its properties are investigated. The crystal growth rate at optimum condition is 0.28 cm/day and their temperature dependence is R(T) = 2.92 x 10S04T exp(-1.548eV/kS1BTT) [cmS02T/day.K]. Etch pits density distribution along radial direction is order of 10S04TcmS0-2T and 10S03TcmS0-2T at the edge and middle of the wafers, respectively, and it increased exponentially along vertical direction of ingot. Moreover,it is uniformly distributed as order of 10S03TcmS0-2T in radial direction of In doped GaAs. The carrier concentration and mobilities are measured to 0.34-2.1 x 10S016T cmS0-3T and 2.3-3.3x10S03T cmS02T/V.sec, respectively.

Effect of Harvest Time on Seed Quality of Silage Corn Inbreds and Hybrids

  • Lee, Suk-Soon;Yun, Sang-Hee;Soo, Jung-Moon;Min, Hwang-Kee;Ryu, Si-Hwan;Park, Jong-Yeol
    • 한국작물학회지
    • /
    • 제47권5호
    • /
    • pp.361-367
    • /
    • 2002
  • In order to determine the optimum harvest time for the seed production of inbreds and hybrids in silage corn, the ears of sib-pollinated 'KS5', 'KS7rhm', and 'Ga209' and cross-pollinated 'KS5' $\times$ 'KS6' (Suwon19), 'KS7 rhm' $\times$ 'KSl17' (Suwonok), and 'Ga209' $\times$ 'DB544'(Kwanganok) were harvested at the one-week intervals from 4 to 10 weeks after silking. The optimum harvest time for the seed production for 'KS5', 'KS5' $\times$ 'KS6', 'KS7 rhm', and 'KS7rhm' $\times$ 'KS117' was 7 weeks after silking considering both emergence rate and plumule growth in cold test. Although earlier harvested seeds showed similar germination rate as the seeds harvested at the optimum time at $25^{\circ}C$, their emergence rate were lower in cold test. Seed weight and $\alpha$-amylase activity of earlier harvested seeds were lower compared to those of seeds harvested at the optimum time, while leakage of total sugars and electrolytes were higher. However, the later harvested seeds showed lower germination rates at $25^{\circ}C$ and emergence rates in cold test probably due to the lower $\alpha$-amylase activity although they showed increased seed weight and reduced leakage of total sugars and electrolytes. In contrast, the emergence rate of 'Ga209' and 'Ga209' $\times$ 'DB544' in cold test increased up to 10 weeks after silking probably due to the increased seed weight and $\alpha$-amylase activity and reduced sugar and electrolyte leakages during the germination. The cross-pollinated F$_1$ hybrid seeds showed higher germination and emergence rates at $25^{\circ}C$ and in cold test, and higher plumule growth and $\alpha$-amylase activity compared to those of sib-pollinated inbreds.

합성용질확산법에 의한 GaP결정의 성장과 전기루미네센스 특성 (On the Crystal Growth of Gap by Synthesis Solute Diffusion Method and Electroluminescence Properties.)

  • 김선태;문동찬
    • 한국재료학회지
    • /
    • 제3권2호
    • /
    • pp.121-130
    • /
    • 1993
  • 합성용질확산법으로 GaP 단결정을 성장시키고, 몇가지 성질을 조사하였다. 결정성장용 석영관을 전기로내에서 1.75mm/day의 속도로 하강시킴으로써 양질의 GaP 단결정을 성장하였다. 에치피트 밀도는 결정의 성장축 방향으로 3.8 ${\times}{10^4}$c$m^{-2}$부터 2.3 ${\times}{10^5}$c$m^2$이었다. 에너지갭의 온도의존성은 실험적으로 $E_g$(T)=[2.3383-(6.082${\times}{10^{-4}}$)$T^2$(373.096+T)eV로 구하여졌다. 저온에서의 광루미네센스 스펙트럼은 구속된 여기자의 복사재결합과 재결합 과정에 포논의 참여로 인하여 에너지갭 부근의 복잡한 선 스펙트럼이 나타났다. n형의 GaP내에서 Zn의 확산깊이는 확산시간의 제곱근에 비례하였으며, 확산계수의 온도의존성은 D(T)=3.2${\times}{10^3}$ exp(-3.486/KbTc$m^2$/sec이었다. p-nGaP 동종접합다이오드의 전기루미제센스 스펙트럼은 깊은 준위의 도너인 Zn-O 복합중심(complex center)과 Zn가 형성한 역셉터 준위사이의 도너-억셉터 쌍 재결합 천이에 의한 630nm의 발광과 에너지갭 부근의 케리어 재결합 처이에 의한 550nm의 발광으로 구성되었으며, 100mA보다 낮은 전류 영역에서 광자의 방출은 bane-filling 과정으로 이루어 진다.

  • PDF