• Journal of the Korean Magnetics Society
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• v.9 no.4
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• pp.177-183
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• 1999

Ultrafine $CoFe_{1.9}Bi_{0.1}O_4$ particles were fabricated by using a sol-gel method and their magnetic and structural properties were investigated with an x-ray diffractometer (XRD), a vibrating sample magnetometer (VSM), and a M$\"{o}$ssbauer spectrometer. The result of x-ray diffraction and M$\"{o}$ssbauer spectroscopy showed that the powders fired at and above 523 K had only cubic spinel structures. M$\"{o}$ssbauer spectra measurements showed that the powders annealed at 523,723 and 823 K possessed ferrimagnetic nature and paramagnetic nature due to superparamagnetism, simultaneously at room temperature and the powders annealed at and above 923 K behaved ferrimagnetically. In the case of the powder annealed at 923 K, the lattice constant was $a_0=8.398$\pm$0.005{\AA}$ and the hyperfine fields were $H_{hf}(A)=479kOe,\; H_{hf}(B)=502kOe$. The isomer shifts indicate that the iron ions are ferric at tetrahedral[A] and octahedral sites [B], respectively. The magnetization as a function of annealing temperature increased as increasing annealing temperature. The largest coercivity values were $H_C=1368\;Oe$ AT 923 K annealing temperature. In the case of the powder annealed at 1123 K, the magnetization value was $M_S=75\;emu/g$ and this value was similler to that of $CoFe_2O_4$.Fe_2O_4$.

• Journal of the Korean Magnetics Society
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• v.12 no.1
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• pp.14-19
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• 2002

The iron-doped perovskite La$_{0.67}$Sr$_{0.33}$Mn$_{0.99}$$^{57}$Fe$_{0.01}$O$_3$compound has been studied by x-ray diffraction, Mossbauer spectroscopy, and vibrating sample magnetometry. The single phase of the polycrystalline La$_{0.67}$Sr$_{0.33}$Mn$_{0.99}$$^{57}$Fe$_{0.01}$O$_3$powder has been prepared by a waterbased solgel method. Crystalline La$_{0.67}$Sr$_{0.33}$Mn$_{0.99}$$^{57}$Fe$_{0.01}$O$_3$was a rombohedral structure with lattice parameters a$_{0}$=5.480 $AA$, $alpha$=60.259$^{circ}$. Mossbauer spectra of La$_{0.67}$Sr$_{0.3}$/Mn$_{0.99}$$^{57}$Fe$_{0.01}$O$_3$have been taken at various temperatures ranging from 20 to 400 K. As the temperature increases toward the Curie temperature, T$_{c}$=375 K, the Mossbauer spectra show line broadening and the difference between the 1,6 and 3,4 linewidths is caused by the anisotropic hyperfine field fluctuation. The anisotropic field fluctuation of +H (P$_{+}$=0.80) is greater than -H (P$_{-}$=0.20). We calculated that the anisotropy energy was 124.01 erg/cm$^3$for T=150 K which is associated with the large line broadening.

• 한국가스학회:학술대회논문집
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• 1997.09a
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• pp.121-126
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• 1997

우리나라는 그동안 가스산업에서 고속성장을 이룩해 왔으나, 근래에는 중대가스산업사고가 빈번하게 일어나고 있다. 그런 이유로 1996년도에는 중대산업사고 예방제도가 전면적으로 실시되고 공정안전보고서를 자성하여 제출하도록 함으로서 위험성 평가의 중요성이 점차 높아가고 있으며, 위험성 평가 기법들에 대하여 여러 연구 단체에서 연구${\cdot}$ 시도되고 있다. 또한 이러한 연구${\cdot}$보고된 위험성 평가 기법들을 프로그램화하고 적용하려는 시도가 많이 있어 왔다. 본 연구에서는 기존에 연구${\cdot}$개발된 위험성 평가 기법들에 최근 컴퓨터 산업의 발달에 힘입어 각광을 받고 있는 지리정보시스템을 적용하고자 한다. 이러한 가스산업시설의 위험성 평가 시스템은 위험성을 평가하기 위해서 필요한 여러 가지 정보들을 지리정보시스템이 속성 데이터로서 저장하고 있으며, 가스산업시설에 관련된 주변의 도민들을 공간 데이터로서 저장하고 있다. 그리고 위험성 평가 시스템의 세부적인 기능을 모듈화하였다. 우선 위에 언급한 속성 데이터와 공간 데이터를 관리하는 모듈과 이러한 데이터를 가지고 사고영향 범위를 산출해내기 위한 모듈, 그리고 산출된 사고 영향 범위를 도면에 나타내는 모듈로 나뉘어져 있다. 이렇게 지리정보시스템에 구축되어 있는 도면에 위험성을 평가한 결과치를 나타냄으로서 위험성 평가 숙련자가 아니더라도 위험성 평가를 할 수 있고 결과를 분석하도록 도와 줄 수 있도록 할 수 있다. 또한 향후 재난관리시스템에서는 도면상의 도로에 교통량 가중치와 인근 소방서와 경찰서등의 위치를 관리하도록 지리정보시스템을 적용할 수 있으며, 가스시설물 관리시스템에서는 최근 대형가스사고의 대부분이 타공사에 의한 것임을 고려하여 가스배관망을 포함하여 기타 다른 지하배관망을 관리하도록 지리정보시스템을 적용할 수 있다.기질로서 이용하지 못하므로 invertase 및 ${\alpha}-glucosidase$ 활성이 없는 것으로 나타났다.)의 모양은 배양에 의해 형성된 균핵(菌核)의 모양과 다소 차이가 있었다. R. cerealis의 균사생장(菌絲生長) 적온(適溫)은 $23^{\circ}C$였으며, 다른 균핵진균(菌核眞菌)들의 균사생장(菌絲生長) 적온(適溫)은 $27-33^{\circ}C$였다. 일부 균핵진균(菌核眞菌)들의 균사생장(菌絲生長) 최고온도(最高溫度)는 $41^{\circ}C$ 로서 높은 반면, R. cerealis 의 균사생장(菌絲生長) 최고온도(最高溫度)는 $31^{\circ}C$로서 낮았다. R. cerealis 의 균사생장(菌絲生長) 최저온도(最低溫度)는 $2^{\circ}C$ 였으며, 다른 균핵진균(菌核眞菌)들의 균사생장(菌絲生長) 최저온도(最低溫度)는 $6-10^{\circ}C$였다. 시술(施術)하였다. 10. 한양방향시치료시(韓洋方同時治療時) 양호이상(良好以上)의 효과(效果)를 보인 경우(境遇)가 30건중(件中) 21건(件)으로 70%의 치료효과(治療效果)를 보여 한방단일진료시(韓方單一診療時)보다 다소 높은 치료효과(治療效果)를 나타냈다. 11. 1일평균(日平均) 한방진료건수(韓方診療件數)는 26.95명(名)이었고, 1일평균(日平均) 한방초진환자수(韓方初診患者數)는 3.9명(名)으로 나타났으며, 한방진료(韓方診療)가 양한방(洋韓方) 총진료(總診療)의 23.20%를 차지했고, 1일(日) 평균(平均) 한양방(韓洋方) 총진료건수(總診療件數)에 대(對)해 1일(日) 평균(平均) 한방초진건수(韓方初診件數)가 21.51%를 차지하는 것으로 나타났다.험이 완료된 31명에서는 부작용이 없거나 경도의 부작용이 있었으나 임상적

• The Journal of the Petrological Society of Korea
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• v.13 no.3
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• pp.161-177
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• 2004

The Cretaceous pink granites of the finan area, southwestern Ogcheon belt, are adjacently developed in the eastern part (Keg) and western part (Kwg) as stocks, respectively. Keg of rounded shape occur as mainly medium-coarse grained rocks, whereas Kwg of ellipsoidal shape occurs as medium-coarse grained ones with partly porphyritic and fine-grained textures. Miarolitic cavities of them are often seen and can be observed more frequently in Kwg than Keg. Rose and counter fracture diagrams of the two granites show that Keg and Kwg have more potentiality of non-dimension and dimension to non-dimension stones, respectively. Physical properties such as porosity and absorption ratio have 0.25% and 0.65％, and 0.43% and 1.11%, respectively, which could suggest that emissions of gas phase at later magma stages are abundant in Kwg than those of Keg. From the major and trace elements petrochemisoy, they belong to acidic, peraluminous and calc-alkaline rocks, showing that Kwg are later product than Keg of the same granitic parent magma. REE concentrations normalized to chondrite value have trends of gradual and parallel enriched LREE and depleted HREE. Eu negative anomalies of Kwg are far more severe than those of Keg, which suggest that plagioclase fractionation in Kwg was much stronger than that of Keg. In the magnetic susceptibility vs. petrochemical and modal parameters, they all belong to magnetite-series and I-types, and can be classified as weakly-moderately ferromagnetic rocks. And the above relations could suggest that their susceptibility values are more mainly depended on ferromagnetic opaques than ferromagnetic and paramagnetic assemblages (Bt ＋ Ch ＋ Ser ＋ Op).

• Proceedings of the Korea Information Processing Society Conference
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• 2003.11a
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• pp.115-118
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• 2003

최근 MOM 기술은 비즈니스 로직을 수행하는 애플리케이션 서버의 필수적인 구성요소로서 자리잡고 있으며, 보통 수백에서 수천의 클라이언트 요청을 처리할 수 있는 능력을 제공한다. MOM 은 이러한 대용량의 클라이언트 요청을 효과적으로 처리하기 위해서 효율적이고 확장성있는(스케일러블) 네트워크 모듈이 필요하며, 다양한 네트워크 프로토콜을 지원해야 한다. MOM이 기본적으로 지원하는 메시징 기능은 PTP(Point-To-Point)와 publish/subscribe 메시징 도메인으로 나뉘는데 이 논문에서는 두 가지 메시징 도메인과 그룹통신 메시징 서비스 기능을 동시에 지원하는 MoIM-Message 시스템의 하부 통신 모듈의 설계에 대해 기술한다. PTP와 publish/subscribe 메시징을 지원하기 위해 세가지 프리미티브 메시징 오퍼레이션인 "synchronous send", "synchronous receive", "asynchronous receive"를 정의하였으며 하부 통신 모듈 역할을 하는 메시지 트랜스포트 관리 계층내의 트랜스포트 관리자 내에 구현되었다. 트랜스포트 관리자는 다양한 트랜스포트 프로토콜을 적용할 수 있도록 하기 위해 트랜스포트 어댑터로 설계되었으며, 대량의 통신 요청을 효과적으로 처리하기 위해 "polling with multiple service thread model" 기법을 적용하여 구현되었다. 또한, 모바일 클라이언트 환경을 지원하기 위해 클라이언트 측 통신 모듈을 IPaq PDA 상에 포팅하였다. 본 논문에서 제안하는 세 가지 프리미티브 메시징 오퍼레이션을 제공하는 통신 모듈은 MOM이 기본적으로 지원해야 할 메시징 도메인과 대용량의 클라이언트 요청을 효율적으로 처리할 수 있는 구조를 가진다.es}8$ 모드를 모두 사용한 경우와 $8{\times}8$ 단일모드를 사용한 경우보다 계산 시간이 감소하였음을 확인하였다.행중인 MoIM-Messge서버의 네트워크 모듈로 다중 쓰레드 소켓폴링 모델을 적용하였다.n rate compared with conventional face recognition algorithms. 아니라 실내에서도 발생하고 있었다. 정량한 8개 화합물 각각과 총 휘발성 유기화합물의 스피어만 상관계수는 벤젠을 제외하고는 모두 유의하였다. 이중 톨루엔과 크실렌은 총 휘발성 유기화합물과 좋은 상관성 (톨루엔 0.76, 크실렌, 0.87)을 나타내었다. 이 연구는 톨루엔과 크실렌이 총 휘발성 유기화합물의 좋은 지표를 사용될 있고, 톨루엔, 에틸벤젠, 크실렌 등 많은 휘발성 유기화합물의 발생원은 실외뿐 아니라 실내에도 있음을 나타내고 있다.>10)의 $[^{18}F]F_2$를 얻었다. 결론: $^{18}O(p,n)^{18}F$ 핵반응을 이용하여 친전자성 방사성동위원소 $[^{18}F]F_2$를 생산하였다. 표적 챔버는 알루미늄으로 제작하였으며 본 연구에서 연구된 $[^{18}F]F_2$가스는 친핵성 치환반응으로 방사성동위원소를 도입하기 어려운 다양한 방사성의 약품개발에 유용하게 이용될 수 있을 것이다.었으나 움직임 보정 후 영상을 이용하여 비교한 경우, 결합능 변화가 선조체 영역에서 국한되어 나타나며 그 유의성이 움직임 보정 전에 비하여 낮음을 알 수 있었다. 결론: 뇌활성화 과제 수행시에 동반되는 피험자의 머리 움직임에 의하여 도파민 유리가 과대평가되었으며 이는 이 연구에서 제안한 영상정합을 이용한 움직임 보정기법에

• Membrane Journal
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• v.18 no.4
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• pp.282-293
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• 2008

Partially sulfonated poly(aryl ether sulfone) membranes were prepared from the sulfonated sulfone monomer, which was synthesized by a nucleophilic substitution, non-sulfonated monomers and potassium carbonate by a direct polymerization method and a subsequent solution casting technique with mixed solvents of N-methyl-2-pyrrolidone (NMP) and dimethylacetamide (DMAc). To investigate the effect of mixed solvent, the volume ratios of NMP and DMAc were varied in the range of $0{\sim}100%$ and the degrees of sulfonation of the copolymers were fixed as 50%. The surface properties of the resulting membranes were examined by scanning electron microscope (SEM) and atomic force microscope (AFM), and a comparative study of the morphology changes and the physicochemical properties such as proton conductivity and methanol permeability was achieved. It was found that proton conductivities depend on the volume ratio of NMP-DMAc mixed solvents, and the proton conductivity determined at the condition of $25^{\circ}C$ and 100% relative humidity was $1.38{\times}10^{-1}\;S/cm$ for the membrane prepared in the 50:50 v/v-% of NMP : DMAc mixed solvent.

• Korean Journal of Materials Research
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• v.5 no.2
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• pp.239-245
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• 1995

Mn-Zn ferrite thin films were deposited on $SiO_2(1000 \AA)/Si(100)$ by ion beam sputtering using a single ion source. A mosaic target consisting of a single crystal(ll0) Mn-Zn ferrite with a Fe metal strip on it was used. As-deposited films without oxygen gas flow have a wiistite structure due to oxygen deficiencies, which originated from the extra metal atoms sputtered from the metal strips during deposition. The as-deposited films with oxygen gas flow, however, have a spinel structure with (111) preferred orientation. The crystallization of thin films was maximized at the ion beam extraction voltage of 2.lkV, at which the deposited films are bombarded appropriately by the energetic secondary ions reflected from the target. As the extraction voltage increased or decreased from the optimum value, the crystallinity of thin films becomes poor owing to a weak and severe bombardment of the secondary ions, respectively. Crystallization due to the bombardment of the secondary ions was also maximized at the beam incidence angle of $55^{\circ}$. The as-deposited ferrite thin films with a spinel structure showed ferrimagnetism and had an in-plane magnetization easy axis.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.4 no.1
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• pp.133-141
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• 1993

Present study investigated the differences in psychological tests responses between chronic motor tic disorder and tourette's disorder to clarify whether chronic motor tic and tourette's disorder constitute a single disorder on a continuum or not. Based on the diagnosis by child psychiatrists 29 chronic motor tic disorder and 10 tourette's disorder children between the age of 6 to 13 were selected, and the psychological tests responses of two diagnostic groups were compared. The results showed that tourette's disorder is more related to neulological problems than chronic motor tic disorder. Also it was found that children with tourette's disorder have more difficulties in social-emotional adjustment than children with chronic motor tic disorder. These results suggested that interactions among neurological factor, emotional factor and temperamental characristics might be more involved in tourette's disorder than in chronic motor tic disorder. The limitations of present study and the need for futher research on the comorbidity of tourette's disorder and ADHD were discussed.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.4 no.1
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• pp.124-132
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• 1993

We studied the clinical characteristics of 45 children with tic symptoms, and a comparison was made according to their birth order patterns. The results were as follows. Sex ration was 14:1 higher for boys. The eldest children were 46.7%, single children, 15.6%, the youngest children, 33.3%, and twins 4.4% of all Organicity was suggested in 37.8%, early developmental problems in 71.1%, and family problems were in 89.9%. Among the co-existing problems, ADHD 46.7%, OCD 17.7%, Separation anxiety disorder 24.4%, GAD or anxiety dreams 17.8%, somatization disorder and enuresis 13.3% each, stuttering 8.9%, and other conditions. Overall, 84.4% of the patients have one or more co-existing conditions other than tic symptoms. When compared according to birth order patterns, the most significant difference was the time of onset The youngests have more incidences around the entrance period for elementary school(p<0.01). Among the twins, the lower birth-weight child was the patient. Summing up these findings, we concluded there were significant environmental factors working on the manifestation of tic and tourette disorders.

• Journal of the Korean Magnetics Society
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• v.3 no.3
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• pp.179-184
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• 1993

The X-ray diffraction pattern of amorphous $Fe_{78}Si_{9}B_{13}$ alloy was analyzed to obtain the radial distribution function (RDF) where the first peak was in the form of Gaussian function. The calculated coordination number of the form of Gaussian functiono The calculated coordination number of the sample is 13.5, the mean distance betweeon near-neighbor atoms $r_{0}$ is $2.595{\AA}$ and a Gaussian parametet ${\delta}r$ indicating near-neighbor atomic distri-bution is $0.27{\AA}$. The temperature dependence of saturated magnetization at low temperature could be explained by spin wave excitations theory yielding the spin wave stiffness constant as $117.8\;meV\;{\AA}^2$. Also, we tried to fit the observed temperature dependence of saturated magnetization with the Handrich's equation of the modified molecular field theory for the amorphous ferromagnet. Nice fittings are obtained when we used the parameters ${\Delta}=0.32$(S=1/2) and ${\Delta}=0.23$(S=1), respectively. Finally, the calculated spin wave stiffness constant using the parameters and the structural data are $149\;meV\;{\AA}^2$ for S=1/2 and $138\;meV\;{\AA}^2$ for S=1, respectively. The mean exchange coupling integral between near-neighbor atoms was estimated to be 17.9 meV for S=1/2 and 6.7 meV for S=1.