• Journal of the Korean Ceramic Society
• /
• v.34 no.1
• /
• pp.109-113
• /
• 1997

When the intensity of X-rays scattered from amorphous materials (very weakly absorbing materials) is measured using standard diffractometric technique, the intensity caused by multiple scattering is obtained in the measured X-ray intensity. Computer programs have been developed to estimate the intensity of the mul-tiple scattering obtained in vitreous SiO2 and B2O3 with various X-rays. Using the above computer program, the intensity ratios of multiple scattering to single scattering in vitreous SiO2 were 0.10~0.16% at CuK$\alpha$, 0.98~5.87% at MoK$\alpha$, and 1.88~17.86% at AgK$\alpha$ in the range of 2$\theta$=0~180$^{\circ}$. Therefore, pri-or to the structural analysis of vitreous SiO2 and B2O3 performed experimentally using X-ray diffractometric technique, the intensity data measured in MoK$\alpha$ and AgK$\alpha$ radiations must be corrected for multiple scattering effect.

• Journal of IKEEE
• /
• v.18 no.4
• /
• pp.593-602
• /
• 2014

One of the purposes of an artificial neural netowrk(ANNet) is to implement the largest number of functions as possible with the smallest number of nodes and layers. This paper presents a CoreNet which has a multi-leveled input value and a multi-leveled output value with a 2-layered ANNet, which is the basic structure of an ANNet. I have suggested an equation for calculating the capacity of the CoreNet, which has a p-leveled input and a q-leveled output, as $a_{p,q}={\frac{1}{2}}p(p-1)q^2-{\frac{1}{2}}(p-2)(3p-1)q+(p-1)(p-2)$. I've applied this CoreNet into the simulation model 1(5)-1(6), which has 5 levels of an input and 6 levels of an output with no hidden layers. The simulation result of this model gives, the maximum 219 convergences for the number of implementable functions using the cot(${\sqrt{x}}$) input leveling method. I have also shown that, the 27 functions are implementable by the calculation of weight values(w, ${\theta}$) with the multi-threshold lines in the weight space, which are diverged in the simulation results. Therefore the 246 functions are implementable in the 1(5)-1(6) model, and this coincides with the value from the above eqution $a_{5,6}(=246)$. I also show the implementable function numbering method in the weight space.

• Journal of IKEEE
• /
• v.22 no.3
• /
• pp.638-644
• /
• 2018

In this paper, we develop a measurement system that uses 3D Scintillator and NaI(TI) Detector to 3-dimensionally identify the location of multiple radiation sources in moving vehicle loads. The radiation measurement system consists of radiation measurement (plastic scintillator), 2-channel Pulse Counter Board, nuclide analysis (NaI(TI) detector) and 1 channel MCA Board. The source locator algorithm calculates the coordinate value of the ratio of the CPS value($1/r^2$) of the source according to the angle(${\theta}$) in inverse proportion to the square of the distance(X, Y) through the SVM classification. The coordinate values are input every predetermined period of the spectrum, and after analyzing the spectrum per unit cycle, the position of the nuclide at the time is calculated by determining whether or not the nuclide is present in the remaining part except for the background area. As a result of the position discrimination test, the error within the international standard of ${\pm}1m$ was shown. Thus, the utility of the proposed system has been demonstrated.

• The Journal of the Korea Contents Association
• /
• v.10 no.5
• /
• pp.460-466
• /
• 2010

It is well-known that Korean EFL learners have difficulties in producing English fricatives which are not in the inventory of Korean and consequently tend to replace English fricatives with stops. The purpose of this paper is to investigate whether Korean students also have difficulties perceiving English anterior coronal consonants including fricatives. To this end, forty Korean college students participated in an identification test which consisted of 24 nonce words with English anterior coronal consonants in 4 different prosodic locations (CV, VC, VCVV,VVCV). It was shown that the mean accuracy rates were higher in strong position like CV and VCVV than in weak position like VC and VVCV, providing confusion matrices for each target consonant. It was also found that Korean participants had a great difficulty identifying English[$\theta$] and [$\eth$], which are novel in Korean. Importantly, the confusion patterns found in the perception test tended not to be identical with those found in the previous production studies in that both stops and fricatives were misperceived as fricatives while fricatives were misproduced as stops. Further, perceptual devoicing and intervocalic voicing were attested inVC and intervocalic position, respectively. Based on the findings of this study, pedagogical implications were drawn.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
• /
• 1998.11a
• /
• pp.158-162
• /
• 1998

향에 의해 유발되는 감성에 대한 중추신경계 및 자율신경계의 반응의 변화를 측정하기 위해 안정시키는 향과 각성시키는 향을 사용하여 주관적 평가와 동시에 시행하였다. 안정시키는 향으로 1% Lavendar 향을 사용하였고, 각성시키는 향으로 0.8% Jasmin 향을 사용하였으며, 안정상태를 향자극 전후에 측정하여 대조군으로 사용하였다. 중추신경계의 지표로 뇌파측정을 하였고 뇌파의 전극은 international 10-20 system에서 4 채널을 사용하였으며, 자율신경계의 지표로는 심전도, heart rate, 피부저항, 피부온도를 기록하였다. 뇌파의 분석은 Fast Fourier Transform analysis의 power spectra로 하였고, 그 frequency bands는 theta(4-8Hz), alpha(8-l3Hz), beta(14-30Hz)로 하였다 또한 심전도를 이용하여 심전도 상의 연속적인 R-R peak간 시간간격을 시계열 데이터로 재구성한 Heart rate variability 분석도 하였다. HRV 분석을 보다 정확히 할 수 있도록 호흡이 심전도에 미치는 영향을 제거하기 위하여 호흡을 분당 20회로 일정하게 하였다 생체신호 측정과 동시에 실시한 주관적 검사에서 lavendar 향은 친숙하게, jasmin 향은 활기차고 상쾌하고 유쾌하게 평가되었다. 뇌파 분석에서 lavendar 향을 주었을 때 theta의 증가 양상을 보였으며, Jasmin 향을 주었을 때는 모든 채널에서 beta 파의 증가 양상을 보였다. 또한 HRV 분석 결과 부교삼신경의 활동성이 부각되는 HF/LF의 값이 lavendar에서는 대조 자극보다 높게 나타났으며, jasmin에서는 대조자극보다 낮은 값이 나타나는 경향을 보였다. 결론적으로 안정과 각성의 후각 자극으로 인한 감성의 변화를 뇌파와 자율신경계 등의 생체지표로 관찰할 수 있었다.정하는 감성요인의 차이를 알 수 있었으며 또한 essential oil에서는 성별 차이가 없는데 반해 페르몬 향의 경우 성별의 차이를 나타내었다.. 방법을 타액과 혈청내 testosterone 농도 측정에 응용하여 RIA의 결과와 비교하여 본 바 상관관계가 타액에서 r=0.969, 혈청에서 r=0.990으로 두 결과가 잘 일치하였다. 본 실험에서 측정된 한국인 여성의 타액내 testosterone농도는 107.7$\pm$12.0 pmol／l이었고, 남성의 타액내 농도는 274.2$\pm$22.1 pmol／l이었다. 이상의 결과로 보아 본 연구에서 정립된 EIA 방법은 RIA를 대신하여 소규모의 실험실에서도 활용할 수 있을 것으로 사려된다.또한 상실기 이후 배아에서 합성되며, 발생시기에 따라 그 영향이 다르고 팽창과 부화에 관여하는 것으로 사료된다. 더욱이, 조선의 ${\ulcorner}$구성교육${\lrcorner}$이 조선총독부의 관리하에서 실행되었다는 것을, 당시의 사범학교를 중심으로 한 교육조직을 기술한 문헌에 의해 규명시켰다.nd of letter design which represents -natural objects and was popular at the time of Yukjo Dynasty, and there are some documents of that period left both in Japan and Korea. "Hyojedo" in Korea is supposed to have been influenced by the letter design. Asite- is also considered to have been "Japanese Letter Jobcheso." Therefore, the purpose of this study is to loo

• Journal of Life Science
• /
• v.22 no.8
• /
• pp.1077-1084
• /
• 2012

This study investigated the effects of Origanum majorana essential aroma therapy on electrical activity in the brain as evaluated by an electroencephalogram (EEG). The subjects were 29 healthy female young adults, and their sleep quality was assessed by using the Pittsburgh Sleep Quality Index. EEG electrodes were attached at the frontal, temporal, occipital, and parietal lobes according to the international 10-20 system. Subjects were exposed to organic Origanum majorana essential aroma (50 ${\mu}l$) for a period of 3 minutes each before, during, and after aromatherapy. Subjects with good sleep quality showed that Origanum majorana essential aroma increased the theta power at the frontal and temporal lobes of both cerebral hemispheres, the left parietal lobe, and the right occipital lobe. Furthermore, Origanum majorana essential aroma decreased the alpha power at the left occipital lobe and the beta power at the right temporal lobe. On the other hand, subjects with poor sleep quality showed an increase in the theta power at the temporal lobe of both cerebral hemispheres and a decrease in the alpha power at the left parietal lobe by Origanum majorana essential aroma therapy. It is concluded that Origanum majorana essential aroma therapy diminishes the state of wakefulness in the brain; alpha and beta powers were both decreased in the subjects with good sleep quality, but only alpha power was decreased in the subjects with poor sleep quality. Moreover, Origanum majorana essential aroma therapy has a sleep-inducing effect in both subjects with good sleep quality and poor sleep quality.

• Journal of Life Science
• /
• v.19 no.12
• /
• pp.1829-1835
• /
• 2009

Hyperventilation (HV) is routinely induced in order to activate brain waves during an electroencephalogram (EEG). The aim of this study was to examine the effects of HV conditions on EEG and suggested basic data for the standardized procedure. Three degrees of HV were induced for 5 minutes with a ventilation volume of 160 ml/min (control group), 240 ml/min, and 300 ml/min in rats. Powers of delta, theta, alpha, and beta waves were examined by a quantitative EEG. The results showed that there was no significant difference in the powers of all EEG waves between the control and 240 ml/min groups. However, a notable change in EEG powers during HV induced by a ventilation volume of 300 ml/min was observed in the frontal cerebral region as follows: power of the delta was increased by 12.8% (p<0.01), powers of the theta, alpha and beta were decreased by 41.3% (p<0.01), 48.6% (p<0.05), and 41.9% (p<0.05), respectively. Therefore, it is concluded that an increase of about 90% of the normal ventilation volume might be adequate for the hyperventilation, and a useful parameter for evaluation of the qualified hyperventilation might be an alteration of the frontal EEG powers.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.36 no.1
• /
• pp.45-53
• /
• 2000

To analyze the photodegradation mechanism of materials for fisheries facilities which stand for considerable time immediately under or even partly above the water surface, such as cage collar, cage net, stationary fishing gear, egc. after 900 hours exposure, weathering experiments on 3 kinds of netting twines like dyed polyethylene(PE) and nylon, and non-treated high strength PE(Hi-PE) were carried out by using xenon light source. The results obtained are as follows : It was observed by scanning electron micrograph(SEM) that a good protection by pigments was obtained in PE and nylon specimen, while crack was rapidly progressed at the surface of Hi-PE one owing to etching by UVR. There was a little increase in density resulting from reorientation of polymer chain, chain scission, etc. in Hi-PE specimen. A wide angle X-ray diffraction showed that 3 kinds of specimens had no fundamental changes in polymer crystalline structure considering each 2$\theta$ of diffraction peak. Remaining tenacity of netting twines was in order of PE, nylon, and Hi-PE after having been exposed to the effect of 900 hours. PE and nylon treated with stuffs were shown to be more resilient than non-treated Hi-PE as confirmed by SEM.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2000.02a
• /
• pp.89-89
• /
• 2000

AlN 박막은 Al과 N원자의 부분적 이온결합 특성을 가진 공유결합을 한 육방정계의 wurtzite 경정구조의 화합물 반도체로서, III-V족 반도체 중 가장 큰 에너지 갭(6.2 eV), 결정 구조적 이방성, 화학 양론적 결합구조, 높은 탄성종과 전달속도(약 10$\times$106 m/s)와 높은 열전도도, 고온 안정성, 가시광성.적외선 영역에서의 좋은 투과성과 높은 굴절률, 상온 대기압에서의 유일하게 안정적인 특성을 가지고 있어, 절연재료, 내열재료, 저주파 영역 센서의 압전 트랜스듀서, 광전소자, 탄성파 소자 및 내환경 소자, MIS소자 등으로 주목받고 있다. 본 연구에서는 BAW 공진기의 활용을 목적으로 반응성 마그네트론 스퍼터링 방법으로 AIN 압전박막을 제작하여, 증착 조건-질소 농도, 고주파 출력, 전체 스퍼터링 압력, 기판 온도-에 대한 박막의 특성을 조사하였다. AlN 박막의 c축 우선 방위 결정성 및 낮은 투과성, 적당한 굴절률의 특성이 BAW 공진기의 활용을 위한 요건이므로, 각각의 증착 조건하에 제작된 박막은 XRD의 $\theta$/2$\theta$ 스캔 회절상에 의한 결정성의 분석과 우선 성장 결정면의 rocking curve 및 XRD로 측정한 FWHM과 표준 편차로 결정성의 배열성과 소자 응용가능성을 조사하였다. 박막의 표면.단면 미세 구조 및 평활도는 SEM으로 관찰하였으며, Al-N 결합 상태는 XPS와 FT-IR로 분석 조사하였다. 제작된 AlN 박막의 결정성 분석 결과, c축 우선 방위 성장을 위한 스퍼터링 압력에 대한 임계 질소 농도와 임계 스퍼터링 압력이 관찰되었다. 전체 스퍼터링 압력이 6~8 mTorr의 범위에서 나타난 최소 임계질소 농도는 10%, 최대 임계 질소 농도는 60%이며, 4 m Torr 이하 10 m Torr 이상의 전체 스퍼터링 압력에서 박막의 우선 방위성장이 제재된다. 이는 AlN 박막이 형성에 관여하는 질소 이온 양의 충분한 형성에 필요로 하는 질소 가스의 유입량에 따른 것으로 판단된다. AlN 박막의 c축 결정면인 (002) 결정면의 성장을 유도하며 다른 방향으로의 성장을 제어하여 소자 활용에 유용한 박막을 제작하기 위한 고주파 출력은 300W 정도가 적당하며, 기판을 가열하지 않았을 때 낮은 투과도를 나타낸다. 본 연구에 의한 BAW 공진기 활용을 위한 AlN 압전박막의 제작을 위한 최적 증착 조건은 기판의 가열 없이 6~8 mTorr의 전체 스퍼터링 압력에 20~25%의 질소종도, 300W의 고주파 출력이다. 최적 조건에서의 AlN 박막은 약 0.19$^{\circ}$의 FWHM과 약 0.08$^{\circ}$의 표준편차를 가지며, 균일하고 조밀한 표면 미세구조와 주상정 구조의 측면구조, 파장에 대한 약 2.0의 굴절률, 낮은 투과도와 화학 양론적 구조를 가지는 우수한 박막이 형성되었다.

• Journal of Korea Water Resources Association
• /
• v.50 no.2
• /
• pp.129-138
• /
• 2017

In this study, the hydraulic model test was performed for the 3 vertical inlets of the Shinwol rainwater storage & drainage system that Seoul City plans to install, and the control discharge value actually measured was analyzed comparing to the value obtained using the theoretical control discharge equation suggested by Yu and Lee (2009). In the results, it was 66~69% compared to the value obtained from theoretical equation showing that the control discharge value according to the theoretical equation is calculated excessively. The sensitivity analysis by design factor was performed using 3 models conducted in this study and 15 hydraulic experiment models conducted in existing research Yu and Lee (2009). The sensitivity analysis of control discharge equation was performed by dividing $Q_{cm}/Q_{cp}$ into 3 ranges. The suggested equation considered only the influence on the tangential intake structure design factor B, z, ${\beta}$, e/B, so ${\theta}$, L considered complex influence suggested equation needed to be more improved.