• 보존과학연구
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• 통권35호
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• pp.5-23
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• 2014

완형유리구슬을 비파괴 분석법으로 검증하고 충청지역 출토 유리구슬과 비교분석하여 지역별 시대별 유리구슬의 특징을 분류하고자한다. CaO, $Al_2O_3$(안정제), MgO 등 미량검출 성분은 차이가 미미하였으며, $SiO_2$(주제), $Na_2O$(융제) 분석결과 값 차이가 다른 성분에 비해 컸다. 선행연구 비교 분석결과 문성리 유적 Soda Glass 군은 LCHA형, HCLA형, LCA-B형이 모두 나타났으며, 백제시대 유리구슬로 추정된다. Potash glass 군의 경우 문성리 유적 유리 Potash glass 군은 I형, III형이 모두 나타났다. MgO와 $K_2O$ 함량에 따른 융제($Na_2O$) 성분원료 구분하면 선행연구 및 문성리 유적 유리구슬 모두 MgO 와 $K_2O$의 함량이 1.5 wt.% 이하이므로 광물원료에서 소다를 취한 것으로 판단된다. 한국 출토 금박구슬의 계통분류에 따라 문성리 유적 금박유리구슬을 분류하면 금박 네트론유리(Soda Glass) I형(학곡리, 양동리, 탕정, 남산리, 두정동, 복암리) 유사하다.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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• pp.591-597
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• 1996

To straighten the path that farm machinery follows in paddy fields, it is necessary to measure and evaluate the tracks that these machines leave behind. However, there are no known methods for making such measurements and evaluations since it is difficult to accurately trace the paths that the machine make in paddy fields. Therefore, a measuring system has been developed which can accurately recored the path of a farm machinery in a field by measuring the horizontal straight-line distance from the side of the field to the machine. This system consists of a track subsystem on the machine and a range finder system. A measuring appraratus is installed on a flatcar which runs on rails over 50 m long at the side of the filed. The track subsystem uses a CCD camera to track the movement of the machine in the field which is following a lengthwise path. The range finder subsystem measures the distance that the measuring apparatus has traveled on the rails and the distance from the app ratus to the machine in the field. This system makes it possible to record the path that the machine travels. Even though differences in traveling distance arise between the measuring apparatus and the farm machine, these differences are detected by image processing , which allows the machine in the field to be located accurately. The short(0.05 second) time required for image processing is enough to follow an object . In the present study, this system was able to measure the path that a moving tractor makes. Even though a lag of up to 0.4 meters occurred, this system did not miss its target during operation of the track subsystem. Thus the path measuring system developed here is able to record vehicle paths automatically by following the movement of vehicles in the field and measuring the distance to them. It is expected to come into use in such applications as unmanned moving vehicle tests.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2009년도 한국우주과학회보 제18권2호
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• pp.38.1-38.1
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• 2009

In this paper we present the first results of summer-time F region irregularities during low solar condition observed using the Gadanki MST radar. Echoes were observed on all 20 nights of radar observations and were mostly confined to the post-midnight hours. Echo morphology is very different from the equinoxial post-sunset plume-like features reported earlier from Gadanki. Echo SNRs are lower by 25 dB than their equinoxial post-sunset counterpart, and are quite comparable to the equinoxial irregularities in the post-midnight hours, which are essentially the decaying post-sunset irregularities. The Doppler velocities, which lie in the range of $\pm$ 100 m s-1, show upward/northward motion of the irregularities during the initial phase in contrast to the observed predominant downward/southward velocities associated with the decaying equinoxial post-midnight F region irregularities. Spectral widths of the summer echoes, which are well below 50 m s-1 and are very similar to those of the decaying equinoxial irregularities, represent the presence of weak plasma turbulence. Simultaneous observations made using a collocated ionosonde show no ionogram trace during 2200-0530 LT except for a few occasions. Weak frequency type spread F observed during midnight hours occurred without prior occurrence of range spread F. Concurrent ionosonde observations made from magnetic equatorial location Trivandrum also show very similar result and thus no height rise of the F layer during the midnight hours could be monitored. The preliminary analysis suggests that the post-midnight irregularities reported here are mostly freshly generated ones. The observations are discussed in the light of other observational results reported earlier and the current under standing on the post-midnight occurrence F region irregularities in summer.

• 대기
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• 제21권2호
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• pp.131-142
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• 2011

Spectral solar irradiances were observed using a visible and UV Multi-Filter Rotating Shadowband Radiometer on the rooftop of the Science Building at Yonsei University, Seoul ($37.57^{\circ}N$, $126.98^{\circ}E$, 86 m) during one year period in 2006. 1-min measurements of global(total) and diffuse solar irradiances over the solar zenith angle (SZA) ranges from $20^{\circ}$ to $70^{\circ}$ were used to examine the effects of clouds and total optical depth (TOD) on enhancing four solar irradiance components (broadband 395-955 nm, UV channel 304.5 nm, visible channel 495.2 nm, and infrared channel 869.2 nm) together with the sky camera images for the assessment of cloud conditions at the time of each measurement. The obtained clear-sky irradiance measurements were used for empirical model of clear-sky irradiance with the cosine of the solar zenith angle (SZA) as an independent variable. These developed models produce continuous estimates of global and diffuse solar irradiances for clear sky. Then, the clear-sky irradiances are used to estimate the effects of clouds and TOD on the enhancement of surface solar irradiance as a difference between the measured and the estimated clear-sky values. It was found that the enhancements occur at TODs less than 1.0 (i.e. transmissivity greater than 37%) when solar disk was not obscured or obscured by optically thin clouds. Although the TOD is less than 1.0, the probability of the occurrence for the enhancements shows 50~65% depending on four different solar radiation components with the low UV irradiance. The cumulus types such as stratoculmus and altoculumus were found to produce localized enhancement of broadband global solar irradiance of up to 36.0% at TOD of 0.43 under overcast skies (cloud cover 90%) when direct solar beam was unobstructed through the broken clouds. However, those same type clouds were found to attenuate up to 80% of the incoming global solar irradiance at TOD of about 7.0. The maximum global UV enhancement was only 3.8% which is much lower than those of other three solar components because of the light scattering efficiency of cloud drops. It was shown that the most of the enhancements occurred under cloud cover from 40 to 90%. The broadband global enhancement greater than 20% occurred for SZAs ranging from 28 to $62^{\circ}$. The broadband diffuse irradiance has been increased up to 467.8% (TOD 0.34) by clouds. In the case of channel 869.0 nm, the maximum diffuse enhancement was 609.5%. Thus, it is required to measure irradiance for various cloud conditions in order to obtain climatological values, to trace the differences among cloud types, and to eventually estimate the influence on solar irradiance by cloud characteristics.

• Asian Journal of Atmospheric Environment
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• 제8권3호
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• pp.162-174
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• 2014

An abnormal decrease in ozonesonde sensor signal occurred during air-pollution study campaigns in November 2011 and March 2012 in Mexico City Metropolitan Area (MCMA). Sharp drops in sensor signal around 5 km above sea level and above were observed in November 2011, and a reduction of signal over a broad range of altitude was observed in the convective boundary layer in March 2012. Circumstantial evidence indicated that $SO_2$ gas interfered with the electrochemical concentration cell (ECC) ozone sensors in the ozonesonde and that this interference was the cause of the reduced sensor signal output. The sharp drops in November 2011 were attributed to the $SO_2$ plume from Popocat$\acute{e}$petl volcano southeast of MCMA. Experiments on the response of the ECC sensor to representative atmospheric trace gases showed that only $SO_2$ could cause the observed abrupt drops in sensor signal. The vertical profile of the plume reproduced by a Lagrangian particle diffusion simulation supported this finding. A near-ground reduction in the sensor signal in March 2012 was attributed to an $SO_2$ plume from the Tula industrial complex north-west of MCMA. Before and at the time of ozonesonde launch, intermittent high $SO_2$ concentrations were recorded at ground-level monitoring stations north of MCMA. The difference between the $O_3$ concentration measured by the ozonesonde and that recorded by a UV-based $O_3$ monitor was consistent with the $SO_2$ concentration recorded by a UV-based monitor on the ground. The vertical profiles of the plumes estimated by Lagrangian particle diffusion simulation agreed fairly well with the observed profile. Statistical analysis of the wind field in MCMA revealed that the effect Popocat$\acute{e}$petl was most likely to have occurred from June to October, whereas the effect of the industries north of MCMA, including the Tula complex, was predicted to occur throughout the year.

• 대한전자공학회논문지TC
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• 제42권2호
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• pp.61-74
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• 2005

디지털 멀티미디어 방송(DMB)은 대용량의 멀티미디어 정보를 무선환경의 이동체에 전송하기 위해 제안된 방식이다. 이러한 멀티미디어 서비스를 제공하기 위해 DM시스템은 COFDM 변조방식을 사용하여 다중 경로 페이딩 현상을 극복하고, 동시에 강력한 채널오류 정정 능력을 필요로 한다. DMB 수신기를 위한 비터비 디코더(구속장 7, code rate 1/4)는 가변 부호화된 데이터의 복호화를 수행해야 하고, 방송시스템이므로 실시간으로 동작하기 위해서 효율적인 구조를 가져야 한다. 따라서 DMB 시스템을 위한 비터비 디코더를 구현하기 위해서는 복호화 과정을 고속으로 수행할 수 있는 별도의 전용 하드웨어 모듈을 설계하는 것이 바람직하다. 본 논문에서는 많은 연산량을 효율적으로 줄일 수 있는 결합된 Add-Compare-Select(ACS)와 Path Metric Normalization(PMN)구조를 새롭게 제안하고자 한다. PMN구조에서의 단점인 comparison tree에 의한 임계 경로(critical path)의 문제를 고정치(fixed value)에 의한 선택 알고리즘을 적용함으로써 고속 동작이 가능하게 하였고, ACS구조에서는 분할 기법(decomposition method)과 선계산(pre-computation)을 이용하여 덧셈기, 비교기, 표준화기의 복잡도를 줄일 수 있도록 하였다. 시뮬레이션 결과 펑처드 비터비 디코더는 일반적인 구조를 적용했을 때 보다 면적 $3.78\%$, 전력소모 $12.22\%$, 최대 게이트 지연 $23.80\%$의 감소율을 보였다.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제12권1호
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• pp.66-77
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• 2006

본 논문에서는 ON/OFF 스위치 및 ON/OFF 센서만을 이용하여 홈 거주자의 위치탐색 및 추적하고, 이 과정을 원격으로 실시간 모니터링 서비스를 제공할 수 있는 시스템을 설계하였다. 구현환경으로 본 시스템은 우리가 개발해온 분산객체그룹 프레임워크 기반에서 구현되었다. 홈 거주자의 위치를 파악하기 위해서 우리는 개폐기능을 가지는 실내 고정된 위치에 있는 구조/시설물 및 가전제품 등에 ON/OFF스위치 및 ON/OFF 센서들을 부착한 한 흠 구조를 보인다. 홈 거주자에 의해 이들이 개폐(ON/OFF)될 때, ON/OFF 스위치 및 ON/OFF 센서로부터 발생된 신호를 흠 서버 시스템에서 수신한다. 이때 신호가 발생한 실위치가 곧 홈 거주자의 위치가 된다. 홈 서버시스템에서는 실제공간에서 검출된 홈 거주자의 위치를 원격 데스크 탐 시스템이나 이동 단말기의 화면인 가상공간상에 이를 사상(mapping)하여 홈 거주자의 위치를 표현하고, 또한, 탐색된 위치를 시간별로 분석하여 홈 거주자의 이동패턴과 이동영역, 운동량 등을 얻어 헬스케어 정보를 구축하도록 하였다. 마지막으로 본 시스템은 이들 정보를 원격 모니터링 서비스를 위해 제공하도록 하였다.

• 한국컴퓨터정보학회논문지
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• 제20권5호
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• pp.123-131
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• 2015

정보통신의 눈부신 발전은 우리 사회에 편리함과 더불어 또 하나의 문제를 야기하고 있다. 즉 전자기기로 무제한적 감시가 가능한 사회로 변모 되고 있어, 이를 잘못 관리할 경우 또 다른 재앙으로 낳을 수 있다는 문제가 있다. 이러한 사회 속에서 살아가는 우리는 거주지의 문을 나서면서부터 곳곳에 설치되어 있는 폐쇄회로 카메라(CCTV-Closed Circuit Television)와 개인이 사용하는 스마트 폰을 통하여 감시의 덫 속에서 살아가고 있는 것이다. 한편으로는 정보통신의 발전과 함께 개인정보를 쉽게 수집, 저장하게 되면서 기업에게는 마케팅을 위한 기업의 소중한 자산가치가 되면서 이를 불법적으로 수집하고자 하는 사람들이 늘어나게 되고, 실제로 이와 관련된 사건들이 많이 발생하기도 하였다. 이러한 정보사회 속에서는 수사도 범죄행위로 인해 남게 되는 디지털 흔적을 얼마나 잘 찾아낼 수 있느냐가 그 수사의 성공도를 가늠할 수 있을 정도로 여겨지고 있으면서 수사기관은 이를 찾기 위해 노력하게 된다. 따라서 사건을 수사하면서 범죄자가 사용하였던 컴퓨터나 스마트폰의 사용흔적에 관한 압수 수색의 절차는 이제 필수적인 절차가 되었으며, 이러한 전자적인 증거를 수집할 수 있느냐는 수사의 성패를 가름하는 결정적인 요소가 되었다. 그런데 이때 수사기관들은 전자 증거자료들을 압수 또는 수색하면서 포괄적으로 이루어지는 경우가 많아 피압수자의 정보자기결정권을 침해할 우려가 높아지는 추세이다. 따라서 많은 국민들이 수사기관이 행하는 전자정보의 포괄적 압수수색에 대하여 불안감이 노출되면서 '사이버 망명'이라는 용어까지 탄생시키고 있다. 이러한 점에서 전자적 정보의 압수수색 범위를 어떻게 설정하여야 할 것인지를 검토하였다.

• 분석과학
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• 제21권6호
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• pp.487-494
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• 2008

극미량 우라늄시료에 대한 열이온화 질량분석기를 이용하여 우라늄 동위원소 비 측정 및 정량과 관련하여 고순도(zone refined) 레늄필라멘트와 일반 레늄필라멘트로부터 오는 바탕값(background) 특성을 비교하였다. 두 종류 필라멘트에서 가벼운 알칼리금속원소들의 클러스터(cluster)인 $(^{39}K_6)^+$, $(^{39}K_5+^{41}K)^+$ 및 금속산화물($PbO_2$)로 추측되는 우라늄 동중원소영향(isobaric effect)을 확인하였다. 고순도 레늄필라멘트를 < $10^{-7}$ torr에서 약 $2000^{\circ}C$로 1.5 시간 이상 degassing 함으로 불순물들을 완전히 제거할 수 있었으나 일반 레늄필라멘트의 경우 5시간 이상 degassing을 하여도 약 3 pg-U이 남아있었다. 일반 레늄필라멘트에 대한 불순물 제거(degassing) 실험결과 5 A, 30 분이 불순물제거의 최소조건이었다. U-233을 spike로 사용, 동위원소희석 질량분석법으로 일반 레늄필라멘트 중 불순물로 포함된 우라늄 양을 측정한 결과 degassing을 하지 않은 필라멘트에서는 0.31 ng-U이 측정되었고, degassing (5.5 A, 1 hr.)을 한 것은 약 3 pg-U 이 측정되었다. 즉, 일반필라멘트의 경우, degassing을 하더라도 1 ng-U 시료에 대하여 0.3% 오차를 근본적으로 갖는 것을 알 수 있었다. 따라서 환경급 극미량 우라늄시료 측정에는 고순도 필라멘트를 degassing하여 사용해야 함을 알 수 있었다. 우라늄 측정 시 필라멘트 전류를 5.5 A로 하였을 때보다 6.0 A로 했을 때 불순물 우라늄 량이 1.5 배 더 크게 나타났다. 따라서 필라멘트 전류를 5.5 A 이상 올리지 않는 것이 바탕값 영향이 작음을 알 수 있었다. 우라늄 표준물질(KRISS 표준물질/NIST U-005, 030)을 사용하여 우라늄 동위원소 함량을 측정한 후 인증 값과 비교한 결과 U-235 는 0.04%, U-234, U-236는 2% 이내에서 각각 일치하였다.

• 대한가정학회지
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• 제19권2호
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• pp.123-133
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• 1981

If we are to define that the traditional costume is a comprehensive expression of the culture, thoughts, and arts of a country, it is needless to say that the traditional costume would have always reflected the social and cultural aspects of the times. In order words, the cultural contemplation of a certain people at some point the history is only possible when we observe the distintive features of the costume worn by the people of respective times. Although the Korean people had the native costume of its own from the times of the Ancient Choson to the Three Kingdoms of Koguryo, Paekche, and Silla, the Chinese influence on Korean traditional costume became somewhat pronounced ever since the Silla strenghtened the political ties with the T'ang dynasty in China, and it came to a climax when the dual structure in Korean native costume, being compounded with the Chinese touch, continued to be prevailed from the era of the Unified Silla to the Koryo and throughout the succeeding Yi dynasty, thereby copying the typical aspects of Chinese pattern in clothing and dresses worn by the ruling classes, namely the goverment officials including the Kings. Therefore, it is our aim to study the pattern of Chinese influence on our traditional costume, as well as social and cultural aspects by way of contrasting and comparing our official outfit system, which had been developing in dualism since the era of the Unified Silla, with that of China, and to trace in part the Korean traditional costume. In comparing our traditional official outfit system with that of China, we have basically concentrated on the comparison of the official outfit systems during the periods of the Three Kingdoms, the Koryo, and The Yi dynasty with that of corresponding era of Chinese history, namely the dynasties of T'ang, Sung, and Ming, and followed the documentary records for the comparison. Koreans had fallen into the practice of worshipping the powerful in China and begun to adopt the culture and institutions of the T'ang dynasty since the founding of the Unified Silla. From this time forth, Korean people started to wear the clothes in Chinese style. The style of clothing during the period of the Koryo Kingdom was deeply influenced by that of the T'ang and Sung dynasties in China, and it was also under the influenced of the Yuan dynasty(dynasty established by the Mongols) at one time, because of the Koryo's subordinative position to the Yuan. At the close of the Koryo dynasty, the King Kongmin ordered the stoppage on the use of 'Ji-Joung', the name of an era for the Yuan dynasty, in May of the eighteenth year of his rule in order to have the royal authority recognized by a newly rising power dominating the Chinese continent, the Mind. Kind Kongmin presented a memorial, repaying a kindness to the Emperor T'aejo of the Ming dynasty in celebration of his enthronement and requested that the emperor choose an official outfit, thereby the Chinese influence being converted to that of the Ming. As a matter of course, the Chinese influence deepened all the more during the era of the Yi dynasty coupled with the forces of the toadyic ideology of worshipping the China, dominant current of the times, and the entire costume, from the imperial crown and robe to the official outfit system of government officials, such as official uniforms, ordinary clothes, sacrificial robes, and court dresses followed the Chinese style in their design. Koreans did not have the opportunity of developing the official outfit system on its own and they just wore the official outfit designated on separate occasions by the emperors of China, whenever the changes in dynasty occurred in the continent. Especially, the Chinese influence had greatly affected in leading our consciousness on the traditional costume to the consciousness of the class and authority. Judging from the results, Koreans had been attaching weight to the formulation of the traditional outfit system for the ruling classes in all respective times of the history and the formulation of the system was nothing more than the simple following of the Chinese system.