• 한국지역지리학회지
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• 제8권2호
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• pp.216-228
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• 2002

본 연구는 대학생들이 대도시권 지역에서 자신들의 미래 주택지를 어떻게 선택하는지에 대한 의사결정 과정을 분석하였다. 직관적 평가에 의한 일반적 기준의 중요도는 교통, 시설, 교육 사회, 자연환경 그리고 경계 순위로 나타나지만 개인들이 판단한 중요도 순위간의 일치도는 매우 낮다. 교통과 교육 사회에 대한 중요도 순위는 평균에 집중되어 있는 반면에 자연환경과 경계의 순위는 넓게 분산되어 있다. 주택입지 대안에 대한 선호도는 대구 중심과 교외의 중간입지, 대구교외 입지 그리고 대구중심 입지 순위로 선호되고 있다. 세부적 기준의 관점에서 입지 대안들의 선호도는 일반기준에 비해 다양성을 보이고 있다. 민감도 분석에 따르면 시설과 교통의 중요도가 증가하면 중심입지의 선호도가 증가하는 반면에 교외입지 선호도는 감소하고 있다. 이와 대조적으로 자연환경의 중요도가 증가하면 교외입지의 선로도가 증가하고 중심입지의 선호도는 감소한다. 경제의 중요도가 증가하면 종간과 교외의 입지에 대한 선호가 증가하는 반면에 중심입지의 선호는 감소하는 경향을 보이고 있다.

• 대한방사선기술학회지:방사선기술과학
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• 제19권2호
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• pp.79-83
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• 1996

The thermoluminescence(TL) response in changing annealing condition, triboluminescence, and darkroom temperature for $Mg_2SiO_4$:Tb phosphor are examined. The experimental results are summerized as follows : 1. The uniformity of TL intensity is better In the disinfected $Mg_2SiO_4$ : Tb than in contaminated one. 2. The triboluminescence of $Mg_2SiO_4$ : Tb is almost not detected even if numbers of $Mg_2SiO_4$ : Tb falling are increased. 3. The fading effect of $Mg_2SiO_4$ : Tb is scarcely affected by freezing room. The followings are resulted from the study. The disinfected $Mg_2SiO_4$ : Tb phosphor should be used in the dose measurement and the immediate reading for $Mg_2SiO_4$ : Tb after exposure is better. And if the reading is not immediately taken, a law darkroom temperature for $Mg_2SiO_4$ : Tb storage is recommended.

• Journal of Radiation Protection and Research
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• 제23권1호
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• pp.59-63
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• 1998

$Mg_2SiO_4$:Tb(MSO-S) TLD의 사용에서 부정확한 선량평가의 원인이 될 수 있는 광감수성과 방향 의존성을 조사하였다. 200 lux의 형광등과 백열등 하에서 8시간씩 노출한 경우 각각 약 11 mR과 3 mR의 조사선량에 해당하는 광감수성이 나타났다 그리고 수직입사($0^{\circ}$)에 대한 ${\pm}80^{\circ}$ 의 각도로 입사하는 경우의 열형광강도 비가 MSO-S는 약 0.8, badge형의 MSO-L은 약 0.15로서 방향의존성이 비교적 크게 나타났다.

• Transactions on Electrical and Electronic Materials
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• 제3권1호
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• pp.4-8
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• 2002

The typical mold method for FED (field emission display) fabrication is used to form a gate electrode, a gate oxide layer, and emitter tip after fabrication of a mold shape using wet-etching of Si substrate. However, in this study, new mold method using a side wall space structure was developed to make sharp emitter tips with the gate electrode. In new method, gate oxide layer and gate electrode layer were deposited on a Si wafer by LPCVD (low pressure chemical vapor deposition), and then BPSG (Boro phosphor silicate glass) thin film was deposited. After then, the BPSG thin film was flowed into the mold at high temperature in order to form a sharp mold structure. TiN was deposited as an emitter tip on it. The unfinished device was bonded to a glass substrate by anodic bonding techniques. The Si wafer was etched from backside by KOH-deionized water solution. Finally, the sharp field emitter array with gate electrode on the glass substrate was formed.

• 한국응용곤충학회:학술대회논문집
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• 한국응용곤충학회 2002년도 추계 합동 특강 및 학술발표대회
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• pp.74-74
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• 2002

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1998년도 제13차 학술회의논문집
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• pp.195-200
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• 1998

Since the neural network was introduced, significant progress has been made on data handling and learning algorithms. Currently, the most popular learning algorithm in neural network training is feed forward error back-propagation (FFEBP) algorithm. Aside from the success of the FFEBP algorithm, polynomial neural networks (PNN) learning has been proposed as a new learning method. The PNN learning is a self-organizing process designed to determine an appropriate set of Ivakhnenko polynomials that allow the activation of many neurons to achieve a desired state of activation that mimics a given set of sampled patterns. These neurons are interconnected in such a way that the knowledge is stored in Ivakhnenko coefficients. In this paper, the PNN model has been developed using the plasma enhanced chemical vapor deposition (PECVD) experimental data. To characterize the PECVD process using PNN, SiO$_2$films deposited under varying conditions were analyzed using fractional factorial experimental design with three center points. Parameters varied in these experiments included substrate temperature, pressure, RF power, silane flow rate and nitrous oxide flow rate. Approximately five microns of SiO$_2$were deposited on (100) silicon wafers in a Plasma-Therm 700 series PECVD system at 13.56 MHz.

• 한국결정성장학회지
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• 제10권6호
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• pp.407-411
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• 2000

전자 package용 저온봉착 유리를 실험적으로 합성하고 이 유리의 결정화 거동을 비등온 조건하에서 열분석기(DTA)를 이용하여 조사하였다. 이 유리의 조성을 미량의 CaO, $SiO_2$$A1_2$$O_3$ 및 $P_2$$O_5$ 등이 함유된 PbO-ZnO-$B_2$$O_3$-$TiO_2$유리로부터 결정하였다. 연 티탄산염($PbTiO_3$)생성에 해당되는 결정화 발열이 관찰되었다. 이 $PbTiO_3$의 결정화는 삼차원과정으로 진행되었고 유리기지(glass matrix)로부터 생성되는 이 결정의 평균 활성화에너지는 223$\pm$3 kJ/mo1 이었다.

• 한국수산과학회지
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• 제28권6호
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• pp.793-804
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• 1995

Polychaetous community survey in Tomioka Bay was carried out 5 times seasonally from May 1991 to March 1992 by quantitative grab sampling (0.05m2) at 11 stations. Based on the granulometric composition and environmental factors, a homogeneous soft bottom was found in St.5-10. The species of the polychaete were classified into three feeding groups using the Fauchald and Jumars' feeding guild system. According to polychaetous community composition data, deposit feeders predominate in sandy silt area where the silt-clay content is $60-69.3\%.$ These deposit feeders were subdivided into surface deposit feeders and subsurface deposit feeders by their living position and mode. Also, suspension feeding group comes as the third dominant group. Seasonal changes of each feeding group were described in terms of numerical density and biomass. Feeding layer and types of dominant species (Lumbrineris longifolia: surface deposit feeder; Praxillella pacifica: subsurface deposit feeder; Chone duneri; suspension filter feeder, etc.) were examined in the intact sediment core samples. Also, longterm density change among the three dominant species during 10 years was disussed.

• 한국안광학회지
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• 제1권2호
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• pp.49-55
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• 1996

본 연구에서는 LFPCVD법으로 수소화왼 비정질 탄소(a-C:H) 박막을 제작하였으며, 수소화된 비정질 규소 (a-Si:H)에서 주로 나타나는 지속광전기전도도(PPC) 현상을 a-C:H에서 처음으로 관찰하였다. 관찰된 PPC의 크기는 실온에서 암전기전도도의 3배 이상이며, 수 시간 이상 지속되었다. PPC의 크기는 조광시간이 증가함에 따라서 증가를 하며, 조광온도가 증가함에 따라서는 감소를 하여 $120^{\circ}C$ 이상에서 완전히 사라졌다. 또한 PPC의 붕괴는 확장지수붕괴(Stretched Exponential Decay) 함수로 설명할 수 있었다. 이로 미루어 볼 때 a-C:H에서의 PPC는 시료의 이질성과 밀접한 관련이 있다고 생각된다.

• The Journal of Korean Physical Therapy
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• 제14권4호
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• pp.119-130
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• 2002

The purpose of this study was to evaluate hemodynamics of intracranial blood flow for obtain clinically useful reference values and assess cerebral hemodynamics change with aging. 81 normal Korean subjects(age, 14$\thicksim\∼\thicksim$70 years) examined who han no history of neurologic disease and the subjects divided into group A(age, 14$\∼$39 years), group B(age, 40$\∼$59 years) and group C(age, 60$\∼$70 years). Transcranial doppler was use for measured the maximum velocity(Vmax), mean velocity(Vmean), pulsatility index(PI), resistive index(RI), stenosis index(SI) and depth of sample volume. Vmax was 99.1 1cm/s, Vmean was 63.57cm/s, PI was 0.85, RI was 0.56, SI was 31.94 and depth of sample volume was 52.35 in middle cerebral artery. Vmax was 85.54cm/s, Vmean was 52.52cm/s, PI was 0.82, RI was 0.55, SI was 34.48 and depth of sample volume was 73.62 in anterior cerebral artery. Vmax was 75.45cm/s, Vmean was 45.60cm/s, PI was 0.82, RI was 0.58, SI was 36.14 and depth of sample volume was 62.35 in posterior cerebral artery. Vmax was 70.44cm/s, Vmean was 47.07cm/s, PI was 0.87, RI was 0.58, SI was 29.83 and depth of sample volume was 75.23 in basilar artery Vmax was 63.92, Vmean was 42.42, PI was 0.89, RI was 0.58, SI was 29.89 and depth of sample volume was 66.65 in vertebral artery. Vmax and Vmean was significantly decreased with increasing age in middle cerebral artery, anterior cerebral artery, posterior cerebral artery, basilar artery and vertebral artery And PI and RI was significantly increased with increasing age in basilar artery and vertebral artery. And I suggest that transcranial doppler sonography can be used as one of useful clinical tool for detection of cerebral hemodynamics.