• 국제초고층학회논문집
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• 제8권4호
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• pp.313-324
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• 2019

This paper presents the analysis of wind speeds data measured on top of three neighboring high-rise buildings close to a beach in Xiamen city, China, during Typhoon "Usagi" 2013. Wind tunnel simulation was carried out to validate the field measurement results. Turbulence intensity, turbulence integral scale, power spectrum and cross correlation of recorded wind speed were studied in details. The low frequency trend component of the typhoon speed was also discussed. The field measurement results show turbulence intensity has strong dependence to the wind speed, upwind terrain and even the relative location to the Typhoon center. The low frequency fluctuation could severely affect the characteristics of wind. Cross correlation of the measured wind speeds on different buildings also showed some dependence on the upwind terrain roughness. After typhoon made landfall, the spatial correlation of wind speeds became weak with the coherence attenuating quickly in frequency domain.

• 한국자기학회지
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• 제5권5호
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• pp.524-527
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• 1995

The temperature dependence of spin wave mode separation in amorphous $Co_{89.5}Zr_{10.5}$ thin film has been investigated at temperatures between 100 K and 300 K. The magnetization and the spectroscopic splitting factor were obtained for the main resonance mode in parallel and perpendicular magnetic field. ${\Delta}H_{2-3}$, the difference between resonance field of mode 2 and the resonance field of mode 3, increases with decreasing temperature. The linewidth increases for all the modes with decreasing temperature. Especially in mode 3 it increases rapidly below 200 K. This phenomenon could be caused by the increase of exchange stiffness constant or the decrease of surface magnetic anisotropy constant with decreasing temperature.

• Wind and Structures
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• 제25권3호
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• pp.283-299
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• 2017

Two types of aerodynamic admittance function (AAF) that have been adopted in bridge aerodynamics are addressed. The first type is based on a group of supposed relations between flutter derivatives and AAFs. In so doing, the aero-elastic properties of a section could be used to determine AAFs. It is found that the supposed relations hold only for cases when the gust frequencies are within a very low range. Predominant frequencies of long-span bridges are, however, far away from this range. In this sense, the AAFs determined this way are of little practical significance. Another type of AAFs is based on the relation between the Theodorsen circulation function and the Sears function, which holds for thin airfoil theories. It is found, however, that an obvious illogicality exists in this methodology either. In this article, a viewpoint is put forward that AAFs of bluff bridge deck sections are inherently dependent on oncoming turbulent properties. This kind of dependence is investigated with a thin plate and a double-girder bluff section via computational fluid dynamics method. Two types of wind fluctuations are used for identification of AAFs. One is turbulent wind flow while the other is harmonic. The numerical results indicate that AAFs of the thin plate agree well with the Sears AAF, and show no obvious dependence on the oncoming wind fields. In contrast, for the case of bluff double-girder section, AAFs identified from the turbulent and harmonic flows of different amplitudes differ among each other, exhibiting obvious dependence on the oncoming wind field properties.

• 한국세라믹학회지
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• 제38권10호
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• pp.953-957
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• 2001

완화형 강유전체인 $Pb(Mg_{1/3}Nb_{2/3})O_3$계의 상전이 주파수의존성을 조사하기 위해 낮은 전계와 높은 전계 하에서 측정된 물성들을 1 Hz부터 100 kHz에 이르는 주파수 범위에서 비교 분석하였다. $-40{\sim}90^{\circ}C$의 상전이 온도범위에 걸쳐 1 V/mm의 낮은 전계에서 측정된 유전특성의 온도의존성을 구하였고, 수 kV/mm의 강전계 하에서 측정된 유전이력곡선의 기울기로부터 계산된 유전상수의 온도의존성 및 초전전류의 온도의존성을 검토하였다. 모든 실험적 결과와 Vogel-Fulcher 관계식은 비교적 잘 일치되었다. 본 연구를 통하여 유전완화현상은 약전계 조건 뿐 아니라 강전계 조건 하에서도 동일한 거동을 보이는 것을 확인할 수 있었다.

• 전기전자학회논문지
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• 제22권2호
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• pp.446-454
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• 2018

In this work, we summarize the calculation processes of obtaining a scattering factor using with the equilibrium average projection scheme (EAPS), with moderately weak coupling (MWC) interaction, and obtain the line-shape formula of an electron-deformation phonon interacting system interested in the confinement of electrons by squarwell confinement potentials in quantum two dimensional system.. Through the numerical analysis, we analysis the magnetic dependence of absorption power, P(B) in several temperature and frequency difference dependence of absorption power $P({\Delta}{\omega})$, in several external field, where ${\Delta}{\omega}={\omega}-{\omega}_0$ and ${\omega}({\omega}_0)$ is the angular frequency (the cyclotron resonance frequency). The result of equilibrium average projection scheme (EAPS) in SER-MWC explains the properties of quantum transition quite well.

• 한국재료학회지
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• 제21권2호
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• pp.73-77
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• 2011

Specific heat of a crystal is the sum of electronic specific heat, which is the specific heat of conduction electrons, and lattice specific heat, which is the specific heat of the lattice. Since properties such as crystal structure and Debye temperature do not change even in the superconducting state, the lattice specific heat may remain unchanged between the normal and the superconducting state. The difference of specific heat between the normal and superconducting state may be caused only by the electronic specific heat difference between the normal and superconducting states. Critical temperature, at which transition occurs, becomes lower than $T_{c0}$ under the influence of a magnetic field. It is well known that specific heat also changes abruptly at this critical temperature, but magnetic field dependence of jump of specific heat has not yet been developed theoretically. In this paper, specific heat jump of superconducting crystals at low temperature is derived as an explicit function of applied magnetic field H by using the thermodynamic relations of A. C. Rose-Innes and E. H. Rhoderick. The derived specific heat jump is compared with experimental data for superconducting crystals of $MgCNi_3$, $LiTi_2O_4$ and $Nd_{0.5}Ca_{0.5}MnO_3$. Our specific heat jump function well explains the jump up or down phenomena of superconducting crystals.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 1999년도 춘계연구발표회 논문개요집
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• pp.80-81
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• 1999

• 한국자기학회:학술대회 개요집
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• 한국자기학회 1999년도 추계연구발표회 논문개요집
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• pp.80-81
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• 1999

• Bulletin of the Korean Chemical Society
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• 제17권3호
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• pp.217-219
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• 1996

• 혜화의학회지
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• 제9권1호
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• pp.711-724
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• 2000

I reached following conclusion through a bibliographic study about the drug dependence. 1. The drug dependence is the case that taking drugs continually in order to get around discomfort and get mental drug efficacy. that is also the state of poisoning that shows compulsions that using all means to get drugs. the drug dependence is coincident with alcolism in Oriental Medicine. 2 Medicinal matters that causes the drug dependence consist of two field. one is licit drugs, including a tranquilizer, a sleeping pill, anti-anxiety drug, alcohol, caffeine, tobacco, etc. the other is illict drugs, including opium products, psychostimulant, a hallucinogen, aromatic agent(adhesives, LSD, etc.) 3. Drugs that causes dependences has the habit which causing mental dependences and the medicinal poisining which causing physical dependences. 4. A syndrome of abstain from the drug which rides on all kinds of drugs is analogous to depressive psychosis, epilepsy, insanity, depressive syndromes, disorder of internal organs, histery, dizziness, etc. 5. The drug dependence causes visceral dysfunction, that is chiefly inflammatory lesion of brain, heart lung etc. (inflammatory lesions os mainly due to infect.) and injuries liver which removes toxic agents and kidney which is an excretory organ. 6. The treatment of the drug dependence, which needs at first check the medical record and the syndrome, is consist of the expectant treatment and isolating treatment as a rule and sometimes mental therapeutics is going on at the same time. 7. The oriental medical cure of the drug dependence needs more concrete study.