• 제목/요약/키워드: F0 Range

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혼합원자가 $Sr_{1+x}Dy_{1-x}FeO_{4-y}$훼라이트계의 비화학양론과 물성 연구 (A Study on Nonstoichiometry and Physical Properties of the Mixed Valency $Sr_{1+x}Dy_{1-x}FeO_{4-y}$Ferrite System)

  • 여철현;이은석;편웅범;편무실
    • 대한화학회지
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    • 제32권1호
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    • pp.3-8
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    • 1988
  • $K_2NiF_4$ 형 층상구조를 갖는 새로운 $Sr_{1+x}Dy_{1-x}FeO_{4-y}$ 계에서 x = 0. 00, 0. 25, 0. 50, 0. 75 및 1. 00 인 비화학양론적 화합물 고용체를 1200$^{\circ}$C 대기압하에서 제조하였다. X-선 회절분석에 의하여 결정구조학적 상들은 모든 시료의 경우 정방정계임을 알 수 있었다. Mohr 염 분석으로 비화학양론적 화학식을 결정하였고 x가 증가함에 따라 $Fe^{4+}$의 몰수(${\tau}$값)가 증가하였다. $-100{\sim}200^{\circ}$C의 온도범위에서 측정한 각 시료의 전기전도도는 $l0^{-8}{\sim}10^{-2}(ohm^{-1}{\cdot}cm^{-1}$)범위의 반도성을 보이며 활성화 에너지는 0.02∼0.08(eV)의 범위에서 변하였다. $Sr_{1.00}Dy_{1.00}FeO_{4.04}$에 대한 $Fe^{3+}$$Fe^{4+}$의 혼합원자가 상태를 200K에서 측정한 Mossbauer spectrum으로 재확인하였다.

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홍채인식용 광학계 설계 (Optical system design for recognition of human iris)

  • 홍경희
    • 한국광학회지
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    • 제11권6호
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    • pp.390-394
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    • 2000
  • 사람의 홍채 인식을 통항 보안 통제를 하기 위한 광학계를 설계하였다. 이 렌즈는 종색수차와 Petzval sum을 최소로 하는 triplet형이다. 초점거리를 50mm 유효경을 10mm로 하였고 물체로부터 상까지의 거리는 200mm-300mm로 고려하였다. 눈을 고려한 전체 광학계의 성능은 ray-fan과 spot diagram 그리고 회절광학적인 MTF를 계산하여 평가하였다. 홍채의 크기를 고려하여 물체 높이 0mm, 4mm 그리고 6mm 에 대하여, 파장은 Fraunhofer C, d 및 F-line에 대하여 모두 계산한 결과 spot 크기는 0.05mm 직경을 벗어나지 않았고 MTF 값도 물체 높이 6mm에 대한 486mm 파장의 sagittal MTF를 제외하고는 20 lines/mm의 공간주파수에서 0.5이상이 되었다.

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Study on Genetic Diversity of Six Duck Populations with Microsatellite DNA

  • Wu, Yan;Liu, Xiao-Lin;Hou, Shui-Sheng;Huang, Wei
    • Asian-Australasian Journal of Animal Sciences
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    • 제21권6호
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    • pp.776-783
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    • 2008
  • In this study, we investigated the genetic diversity and phylogenetic relationship of six duck populations by employing the genetic polymorphisms of 20 microsatellites. The parameters used in this study included number of alleles, average effective numbers of alleles (E) and average rates of heterozygosity of each population. The results showed that all the microsatellite loci were highly polymorphic except that the locus AJ515896 in Muscovy duck was 0. The average PIC (0.762), average h (0.7843) and average E (5.261) of the six duck populations were all high, indicating that the gene polymorphisms and genetic diversity were high. The test of Hardy-Weinberg equilibrium showed that the six populations in this study were all in Hardy-Weinberg disequilibrium. The F-statistic analysis results showed the range of FST was from 0.0205 (AJ515895) to 0.2558 (AJ515896). The mean FST was 0.0936. Phylogenetic study revealed that Peking duck (Z1 and Z4), Shaoxing duck, Cherry Valley duck and Aobaixing duck were clustered in one group, while the Muscovy duck was clustered in one group alone. The phylogenetic relationships among different populations were in accordance with their breeding history and distribution. Our data suggested that the 20 microsatellite loci were effective markers for analysis of genetic relationships among duck populations.

Mapping the real-space distributions of galaxies in SDSS DR7

  • Shi, Feng
    • 천문학회보
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    • 제44권1호
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    • pp.78.1-78.1
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    • 2019
  • Using a method to correct redshift space distortion (RSD) for individual galaxies, we mapped the real space distributions of galaxies in the Sloan Digital Sky Survey (SDSS) Data Release 7(DR7). We use an ensemble of mock catalogs to demonstrate the reliability of this extension, showing that it allows for an accurate recovery of the real-space correlation functions and galaxy biases. We also demonstrate that, using an iterative method applied to intermediate scale clustering data, we can obtain an unbiased estimate of the growth rate of structure $f\sigma_8$, which is related to the clustering amplitude of matter, to an accuracy of $\sim 10\%$. Applying this method to the Sloan Digital Sky Survey (SDSS) Data Release 7 (DR7), we construct a real-space galaxy catalog spanning the redshift range $0.01 \leq z \leq 0.2$, which contains 584,473 galaxies in the North Galactic Cap (NGC). Using this data we, infer $0.376 \pm 0.038$ at a median redshift z=0.1, which is consistent with the WMAP9 cosmology at $1\sigma$ level. By combining this measurement with the real-space clustering of galaxies and with galaxy-galaxy weak lensing measurements for the same sets of galaxies, we are able to break the degeneracy between $f$, $\sigma_8$ and $b$. From the SDSS DR7 data alone, we obtain the following cosmological constraints at redshift $z=0.1$ for galaxies.

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열형센서용 니켈 산화막의 형성 및 특성분석 (Formation of Ni Oxide Thin Film and Analysis of Its Characteristics for Thermal Sensors)

  • 이응안;서정환;노상수
    • 한국전기전자재료학회논문지
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    • 제18권2호
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    • pp.169-173
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    • 2005
  • Ni oxide thin films were formed through annealing treatment in the atmosphere after Ni thin films deposited by a r.f. magnetron sputtering method and then electric and material properties were analyzed for application to thermal sensors. Resistivity of Ni thin films decreased after annealing treatment at 30$0^{\circ}C$ and 40$0^{\circ}C$ for five hours due to crystallization of Ni thin films but the value increased over 45$0^{\circ}C$ because of Ni thin film's oxidation. Resistivity values of Ni thin films were in the range of 10.5 $\mu$Ωcm/$^{\circ}C$ to 2.84${\times}$10$^4$$\mu$Ωcm/$^{\circ}C$ according to the degree of Ni oxidation. Also temperature coefficient of resistance(TCR) values of Ni oxide thin films depended on the degree of Ni oxidation such as 2,188 ppm/$^{\circ}C$ to 5,630 ppm/$^{\circ}C$ in the temperature range of 0 $^{\circ}C$∼150 $^{\circ}C$. The results demonstrate that Ni oxide thin films of annealing treatment at 40$0^{\circ}C$ for 5hours could be more advantageous than pure Ni thin films and Pt thin films from a point of output properties and TCR, applied to thermal sensors.

FeNb 박막의 강자성 공명 연구 (A Study on the Ferromagnetic Resonance of FeNb Thin Films)

  • 임우영;백종성;이수형
    • 한국자기학회지
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    • 제14권4호
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    • pp.120-126
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    • 2004
  • DC 마그네트론 스파터링 방법으로 제작한 F $e_{84}$ N $b_{16}$ (wt.%) 박막의 온도변화에 따른 자기적 특성을 강자성 공명 흡수선의 거동을 통하여 고찰했다 모든 온도영역에서 다수의 체적 모드 스핀파와 한 개 또는 두 개의 표면 모드가 관측되었는데, 이와 같은 현상은 시편 양면의 표면 자기 이방성이 0보다 작은 경우에 나타나는 특성이다. 113-293K 온도영역에서 포화자화는 Bloch의 $T^{2}$ 3/ 법칙과 부합되는 모습을 보였으며, 분광학적 분리인자는 온도변화에 비교적 작은 변화 폭을 보였다 233-293K 온도구간에서 기판과 접하는 시편면의 표면 자기 이방성 상수 Ksl는 온도감소에 따라 그 갈이 비교적 큰 폭으로 증가하는 특성을 나타냈다. 그리고 공기와 접하는 시편면의 표면 자기 이방성 상수 $K_{sl}$ 은 상온에서 -0.322 erg/$\textrm{cm}^2$인 값을 보이다가, 온도가 253 K로 내려가면 -0.394 erg/$\textrm{cm}^2$로 감소한 후, 그 이하의 온도영역에서는 온도에 비교적 둔감한 특성을 보였다.

제주도 토양 중 비이온계 농약의 흡착 및 용탈 특성 (Adsorption and Leaching Characteristics of Nonionic Pesticides in Soils of Jeju Island, Korea)

  • 전시범;현익현;이민규;감상규
    • 한국환경과학회지
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    • 제27권7호
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    • pp.561-575
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    • 2018
  • Agricultural soils around springwaters heavily affected by pesticide run-off and around wells considering the regional characteristics were collected at 24 stations in Jeju Island, and the physicochemical properties and adsorption and leaching characteristics of four nonionic pesticides (diazinon, fenitrothion, alachlor, and metalaxyl) were investigated. The values of the major soil factors affecting the adsorption and leaching of pesticides, namely, soil pH($H_2O$), organic matter content, and cation exchange capacity (CEC), were in the range of 4.64 ~ 8.30, 0.9 ~ 13.1% and 12.7 ~ 31.7 meq/100 g, respectively. The Freundlich constant, $K_F$ value, which gives a measure of the adsorption capacity, decreased in the order of fenitrothion > diazinon > alachlor > metalaxyl, which was identical to their lower water solubility. Among the collected soils, the $K_F$ value was very highly correlated with organic matter content ($r^2=0.800{\sim}0.876$) and CEC ($r^2=0.715{\sim}0.825$) and showed a high correlation with clay content ($r^2=0.473{\sim}0.575$) and soil pH($H_2O$) ($r^2=0.401{\sim}0.452$). The leaching of pesticides in the soil column showed a reverse relationhip with their adsorption in soils, i.e., the pesticides leached more quickly for the soils with lower values of organic matter content and CEC among the soils and for the pesticides with higher water solubility.

고온가열처리에 의한 바다방석고둥 (Omphalius pfeifferi capenteri)의 식품성분 변화 (Changes in Pood Components of Top Shell, Omphalius pfeifferi capenteri by Thermal Processing at High Temperature)

  • 하진환;송대진;김풍호;허민수;조문래;심효도;김혜숙;김진수
    • 한국수산과학회지
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    • 제35권2호
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    • pp.166-172
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    • 2002
  • 바다방석고둥을 원료로 한 신제품 개발에 관한 일련의 기초 연구로 저장성 부여를 위하여 시도하는 고온가열처리 조건 ($F_0$ 5분, $F_0$ 10분, $F_0$ 15분 및 $F_0$ 20분)에 따른 바다방석고둥의 성분변화에 대하여 살펴보았다 바다방석고등 통조림은 살균을 $F_0$ 5분 이상 처리하는 경우 저장 중 팽창관이 발생하지 않았고, 또한 생균수가 검출되지 않아 저장성이 있었다. 고온가열처리 정도가 증가할수록 바다방석고둥의 일반성분 중 수분함량은 감소하였고, 조단백질 함량은 증가하였으며, 조지방 및 조회분 함량은 거의 변화가 없었다. 또한 바다방석 통조림은 고온가열처리 정도가 증가할수록 이취에 관여하는 휘발성염기질소 함량, pH와 색조에 관여하는 갈변도는 증가하였고, 영양에 관여하는 구성아미노산, 무기질과 맛에 관여하는 유리아미노산, TMAO, total creatinine 및 수율 등은 감소하였다. 이들을 색조, 조직감 및 맛에 대하여 관능검사한 결과 자숙처리한 시료에 비하여 모든 항목에서 $F_0$ 10분까지는 차이가 없었으나, 그 이상 가열처리한 경우 품질이 저하하였다고 인지되었다. 이상의 결과로 미루어 보아 바다방석고둥을 고온가열처리하석 신제품을 개발하고자 하는 경우 $F_0$ 값이 10분 이상이면 바람직하지 않은 것으로 판단되었다.

산화티탄 (IV)의 비화학양론에 관한 연구 (Study of the Nonstoichiometry of Titanium Dioxide)

  • 여철현;김대욱;최재시
    • 대한화학회지
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    • 제20권5호
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    • pp.323-332
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    • 1976
  • 산화티탄(IV)의 비화학양론적 화학식인 $TiO_{2-x}$ 혹은 $TiO_{2-(x^0+x')}$의 값 혹은 $x^0+x'$ 값을 특수히 고안한 자기석영마이크로천칭을 사용하여 $1{\times}10^{-6}{\sim}-1$ 기압의 산소압력 범위와 600~$1300^{\circ}C$온도범위에서 측정하였다. 표준상태에서 rutile의 x값에 대한 기준 혹은 $x^0$값은 0.00148이다. 1기압 산소압력하에서 x값은 온도가 상승하면 차차로 감소하여 $1130^{\circ}C$에서는 화학양론적인 rutile을 형성한다. $1{\times}10^{-6}∼1${\times}$10^{-2}$ 기압 산소압력 범위와 600~$1300^{\circ}C$ 온도범위에서 x값은 0.00148 ∼ 0.01719 범위에서 변한다. 위 조건에서 비화학양론적 rutile의 생성엔팔피 $({\Delta}H_f)$는 21.05 ∼ 29.97 Kcal/mole 범위에서 변한다. logx'를 $log Po_2$에 대하여 (혹은 (log x'= 1n/$log Po_2$) 도시한 직선의 기울기에서 계산한 1/n값은 $1{\times}10^{-6}1{\sim}{\times}10^{-4}$기압의 낮은 산소압력 범위에서 $-{\frac{1}{2}}{\sim}-{\frac{1}{4}}$ 범위의 값을 갖는다. rutile의 안전성, 전기전도성, 촉매성, 및 결핍성 등과 같은 이산화티탄(IV)의 여러가지 물성을 x값에 의하거나 x값의 온도와 산소압력 의존성에서 계산한 열역학적인 데이타에 의하여 설명할 수 있다.

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전신성 홍반성 낭창환자의 질병관련 지식정도와 교육 요구도 (Extent of Knowledge on the Disease and Learning Needs of Patients with Systemic Lupus Erythematosus)

  • 송병은;유소연
    • 기본간호학회지
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    • 제6권3호
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    • pp.464-476
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    • 1999
  • This study was conducted between October 1, 1998, and December 31, 1998, in order to provide basic data to develop better self-management educational programs for systemic lupus erythematosus (lupus) patients. In the study, the extent of each patients knowledge on the disease and their learning needs about it were examined for 100 lupus inpatients and outpatients at the Kangnam St. Marys Hospital. Data were collected by using questionnaires to those patients. Frequencies, percentage, average, standard deviation, t-test, ANOVA, and Duncans multiple range test were examined through the SAS program. The result of study follows : 1) The average score of patients knowledge on the disease was 15.7 (range, 7-20; standard deviation, 2.74). Subjects scored higher as far as the extent of their knowledge in the following categories : management of daily life, diet, characteristics of the disease, risk factors, and medication. Two categories shared the highest percentage of correct answers : 99% of subjects correctly identified that fatigue and stress aggravate symptoms of lupus and symptoms of lupus vary among individuals in range and type. However, when subjects were asked if patients should get a regular examination by an ophthalmologist every 4-6 months while they are on medication to treat rashes, lupus can be completely cured, and contraceptives that include a female hormone (estrogen) are good as contraceptive methods, the percentages of correct answers were low (32%, 31%, and 20%, respectively). In terms of subjects knowledge about the disease by their general characteristics, single subjects had more knowledge about the disease than married subjects did (t=2.14, p=0.0353). The extent of knowledge also varied by monthly income (F=4.96. p=0.0097). Those with more formal education had more knowledge about lupus than those who had less formation education did (t=2.95, 0.0039). Additionally, those who were satisfied with their education about the disease had better knowledge about it than those who were dissatisfied with their education did (t=2.71, p=0.0090). 2) The extent to which lupus patients wanted to be educated about the disease was, on average, 64.5 (range, 46-75; standard deviation, 7.91). Areas for which patients requested education are listed here in order : risk factors, sexual lives and patients associations. Patients who had been hospitalized demonstrated wanting more education than those who had not been did(t=3.73, p=0.0003). The extent to which they wanted the information was different by the number of educational sessions they had (F=3.98, p=0.0249). In conclusion, the results above would be considered when the education programme is planned for SLE patients.

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