• 대한치과보철학회지
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• 제43권3호
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• pp.352-362
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• 2005

Statement of problem. Accurate impression is essential to success of implant prostheses. But there have been few studies about the accuracy of fixture-level impression techniques in internal connection implant systems. Purpose. The purpose of this study was to compare the accuracy of two fixture-level impression techniques in two conditions (parallel and divergent) and to assess the effect of tightening sequences and forces on stresses generated on superstructures in internal connection implant system (Astra Tech). Material and methods. Two metal master frameworks made from two abutments (Cast-to Abutment ST) each and a corresponding, passively fitting, dental stone master cast with four fixture replicas (Fixture Replica ST) were fabricated. Ten dental stone casts for each impression techniques (direct unsplinted & splinted technique) were made with vinyl polysiloxane impressions from the master cast. Strain gauges for each framework were fixed midway between abutments to measure the degree of framework deformation on each stone cast. Pairs of strain gauges placed opposite each other constituted one channel (half Wheatstone bridge) to read deformation in four directions (superior, inferior, anterior, and posterior). Deformation data were analyzed using one-way ANOVA and the Tukey test at the .01 level of significance. And the effect of tightening sequences (right-to-left and left-to-right) and forces (10 Ncm and 20 Ncm) were assessed with ten stone casts made from parallel condition by the splinted technique. Deformation data were analyzed using paired t-test at the .01 level of significance. Conclusions. Within the limitations of this study, the following conclusions could be drawn. 1. Frameworks bent toward the inferior side on all casts made by both direct unsplinted and splinted impression techniques in both parallel and divergent conditions. 2. There was no statistically significant difference of accuracy between the direct unsplinted and splinted impression techniques in both parallel and divergent conditions (P>.01). 3. There was no statistically significant difference of stress according to screw tightening sequences in casts made by the splinted impression technique in parallel condition (P>.01). 4. Greater tightening force resulted in greater stress in casts made by the splinted impression technique in parallel condition (P<.01).

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
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• pp.85-92
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• 2002

When the United Nation classified as Korea is the one of the water deficit country. The consensus was made that the water is the one of the precious national resources. Government increases their R/D budget trying to get more clean water bodies. For instances, 'Sustainable Water Resources Development' project is the one of major title in '21 Century Frontier Research project and there are several small research projects are undergoing by the Ministry of Agriculture and KARICO. However, when the environmental preservation issue has been get more emphasis, construction of the Surface Dam met the blockage from the environmentalists due to the problem of the their water buried area. Since the most fitting site for surface dam had been used in the past, some engineer move their focus on modification of the existing Dam's height to enlarge its capacity or dredging the bottom of the reservoir recently However dredging evoke water quality problem in return by accumulated materials at the bottom. Last year the Dong Gang Dam plan has been canceled by environmental problem in water buried area of the reservoir. With the point of this view, ground water gets more focus for the one of the useful alternative for clean water bodies. Underground dam technique which had widely applied once in the early nineteen eighties by the KARICO and attenuated due to engineering insufficiency. The technique is newly studied with the advanced engineering technique. Still groundwater usage rate in Korea is much lower comparing with the advanced countries and has many rooms to develop. Wells, under ground dam and radial collector wells are typical facilities up to now. There is little application in Korea for the Recharge Dam, which had been widely used in the advanced countries. The Recharge Dam is technique to conjunct surface water and groundwater body together, This technique had developed to increase groundwater recharge at the beginning This research is the result of the study on the possibility of the development of the new technology, Groundwater Reservoir' which was modified from Recharge Dam. Groundwater Reservoir is like a deep artificial lakes trenched in hard rock aquifer to get groundwater. The advantage of the Groundwater Reservoir is followings 1) It can be developed at the plains area, not in the deep valley 2) Huge water body can be developed without dam 3) Small buried area comparing surface water dam makes the least environmental effect. 4) Trenching cost can be substitute by the income of the selling rock debris 5) Outfit of the reservoir can be modified to match with the site prospect 6) Rock debris can be used as constructing materials 7) It can be used as groundwater recharge system when the heavy rains comes 8) The reservoir looks like scenery lake with huge clean water bodies.

• 한국국방경영분석학회지
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• 제2권1호
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• pp.127-143
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• 1976

The purpose of this thesis is to study the optimal arrangement of aircraft instrument panels through the human factors approach. Human factors engineering is the process of effectively fitting the human component to the machine component in any man-machine system. The human factors. are especially important to an aircraft pilot who must constantly shift his attention between the instrument panel within the cockpit and the surrounding area of the aircraft. The preliminary part of this study is to find the general patterns of the Korean pilot's eye movements during their various flying maneuvers, and which instruments require the most attention while in flight. It is assumed that all pilots have a general pattern of eye movement when observing the aircraft instrument panel and that an optimum arrangement would be to minimize the eye travel distance between instruments. In this thesis the arrangements of instruments is taken to be the independent variable and the eye travel distance between instruments the dependent variable. la order to compile the information necessary for this study, sixty Korean Air Force pilots were interviewed and requested to complete information forms. These information forms listed various flying maneuvers and listed each instrument used on the instrument panel. The compilation of the information on these completed forms listed the instruments most frequently used by the pilots. The second part of this study was to determine the optimum instrument arrangement. It was necessary to study the various number of possible arrangements of instruments depending upon the number of instruments involved. Therefore, these instruments are grouped by two major functions, The flight instruments were subdivided into three groups, and the engineering instruments were subdivided into six groups. With this subdivision we arrive at the possible number of arrangements of 4,320. Through the simulation method, total eye travel distance for each of these 4,320 arrangements is calculated and the arrangement which appears to be of optimum distance between the most frequently used aircraft instruments is determined. The results of this study indicate that the optimum distance between instruments would be 33,028cm and that the corresponding distance of the instrument panel now being used is 34,288cm. Therefore, an increased efficiency of $3.8\%$ would be realized if the existing aircraft instrument panel were re-arranged according to layout proposed in this thesis.

• 대한토목학회논문집
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• 제36권1호
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• pp.105-114
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• 2016

수도권에는 1일 약 2000만 건의 대중교통카드 전수자료가 생성되고 있으며, 이 자료를 이용하여 시설운영 및 정책방안을 개선하고 도출하려는 시도가 다양해지고 있다. 본 연구는 교통카드에서 생성되는 동적인 수요변화의 예측 가능성을 모형화하는 시도로서 동적 통행수요배정모형을 구축하는 것이 목적이다. 버스의 경우 승객 이동상황이 카드태그(tag)를 통해 비교적 정확하게 파악되므로, 본 연구에서는 버스를 제외한 수도권 도시철도에 대해, 7개 운송기관이 운영하는 노선을 대상으로 적용되는 모형 및 알고리즘을 구축하였다. 구축된 모형은 교통카드자료의 Big Data 속성에 적합하게 연속 시간형 모형으로 구축되었으며, 승객의 경로선택행태를 효과적으로 나타내기 위하여 환승 횟수 증가에 따른 인지파라메타를 구성하였다. 수도권 도시철도 약 800만 쌍에 대하여 모델링한 결과, 연속형 시간기반 모형의 장점이 반영되어 어떤 시간 시점에서도 동적 수요를 분석할 수 있는 특성을 파악하였다. 특히 기존 철도운영기관의 목측조사자료와 비교한 혼잡도 변화를 파악할 때, 모형에서 도출된 혼잡도와 운영기관이 제시한 혼잡도 간에 유사한 추세를 보이고 있어 높은 신뢰도를 보여주고 있다. 본 연구는 철도기관에 한정한 모형으로 향후, 버스-도시철도와 통합된 모형체계 구축과 같은 연구가 필요할 것으로 파악된다.

• 건축역사연구
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• 제20권2호
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• pp.7-22
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• 2011

This study primarily aims to illuminate the characteristics of $Meoreum$ in Korean traditional fitting system according to the respective types and its periodical changes. Using the research findings as a chronological indicator by which to estimate the construction date of the building is the secondary purpose. In this study 42 of $Byeoldang$ and pavilion architecture remaining in $Yeongnam$ district were examined through the field surveys and methods of documentary research. The research results are as follows. First, $Meoreum$, which is located below the windows or doors, provides protection against the outer wind and has the function to prevent some warm air of the room from flowing outside. Second, $Meoreum$ was recorded as $Yoeum$(了音), $Woneum$(遠音), and $Maleum$(末音) in $Yeong-geon-ui-gwe$(營建儀軌) of Joseon period. While $Yoeum$(了音) was used in $Yeong-geon-ui-gwe$(營建儀軌) of 1776 and 1856, $Woneum$(遠音) had been also used continuously since the year of 1800. The word, $Maleum$(末音) can be seen in $Lim-won-gyeong-je-ji$(林園經濟志), published in 1827. $Woneum$(遠音) and $Maleum$(末音) seem to be the $Yi-du$(吏讀) types of expression of $Meoreum$ which is being extensively used now. Third, the kinds of $Meoreum$ can be classified as $TohMeoreum$, $TongMeoreum$, $TongpanMeoreum$, and $JjaneunMeoreum$. $TongMeoreum$ and $TohMeoreum$ were mostly used at the front part of $Ondol-rooms$, the backside of main floor called $Daechung$(大廳), and at the space between $Daechung$ and rooms in the Pavilions and $Byeoldangs$(Annexes) that had been built in the early Joseon dynasty. $TohMeoreum$ was usually used at the bottom parts of windows between $Daechung$ and $Ondol-rooms$. $TongpanMeoreum$ was mainly used in the mid-Joseon period and relatively high height was the distinctive feature of $Meoreum$ at that time. $Jjaneun$ $Meoreum$, used mainly in the late Joseon dynasty, has become lower and lower gradually in height since 19th century, so people could enter the room through the windows(fittings). Such changes in $Meoreums$ types has brought about the flow of human traffic directly from $Toenmaru$, narrow wooden porch running along the outside of a room to $Ondol-rooms$.

• 한국조경학회지
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• 제39권6호
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• pp.110-117
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• 2011

본 연구는 2010년 4월 3일부터 3가지 토양 조성에 따른 섬기린초의 월동 후 생육상태를 측정하였고, 초고-생장시간 생장모형을 개발하고자 하였다. 이를 위해 함수식(Logistic식과 Gompertz식)을 사용하였고, SPSS를 이용하여 비선형 회귀분석을 진행하였다. 섬기린초의 초고-생장시간 생장모형을 통하여 섬기린초 월동 후의 생장과정과 관리방법을 명확하게 파악할 수 있다. 섬기린초의 생육상태 측정치에 의하면, 펄라이트($P_1$)보다는 혼합한 토양($P_2P_1V_1$, $P_1P_2V_1$)의 생육상태가 더 양호하고, 평균초고는 최대 약 2배 정도의 차이가 나타났다. 그리고 섬기린초의 Logistic생장모형과 Gompertz생장모형의 평균결정계수($R^2$)는 0.995, 0.978 순으로 나타났으며, Logistic생장모형의 적합성은 Gompertz생장모형보다 높은 것으로 확인되었다. 또한 섬기린초의 생장모형을 통하여 월동 후의 생장 기간은 3기간으로 나눌 수 있으며, 생장형태는 "비교적 빠른 생장기간---아주 빠른 생장기간---느린 생장기간"으로 구분할 수 있다. 옥상녹화용 섬기린초를 관리할 때 빠른 생장기간에서만 관리하면 섬기린초의 생육상태는 많이 좋아질 것으로 판단된다.

• 한국결정성장학회지
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• 제16권5호
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• pp.189-197
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• 2006

[$AgGaSe_2$] 단결정 박막을 수평 전기로에서 합성한 $AgGaSe_2$ 다결정을 증발원으로하여, hot wall epitaxy(HWE) 방법으로 증발원과 기판(반절연성-GaAs(100))의 온도를 각각 $630^{\circ}C,\;420^{\circ}C$로 고정하여 성장하였다. 이때 단결정 박막의 결정성은 광발광 스펙트럼과 이중결정 X-선 요동곡선(DCRC)으로 부터 구하였다. $AgGaSe_2$의 광흡수 스펙트럼으로부터 구한 온도에 의존하는 에너지 밴드갭 $E_g(T)$는 Varshni 공식에 fitting한 결과 $E_g(T)=1.9501eV-(8.79x10^{-4}eV/K)T^2(T+250K)$를 잘 만족하였다. 성장된 $AgGaSe_2$ 단결정 박막을 Ag, Ga, Se 분위기에서 각각 열처리하여 10K에서 photoluminescience(PL) spectrum을 측정하여 점 결함의 기원을 알아보았다. PL 측정으로 부터 얻어진 $V_{Ag},\;V_{Se},\;Ag_{int}$, 그리고 $Se_{int}$는 주개와 받개로 분류되어졌다. $AgGaSe_2$ 단결정 박막을 Ag 분위기에서 열처리하면 p형으로 변환됨을 알 수 있었다. 또한, Ga 분위기에서 열처리하면 열처리 이전의 PL 스펙트럼을 보이고 있어서, $AgGaSe_2$ 단결정 박막에서 Ga은 안정된 결합의 형태로 있기 때문에 자연 결함의 형성에는 관련이 없음을 알았다.

• 복식
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• 제6권
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• pp.7-26
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• 1982

Investigation for industrial revolution has been recognized as an important issue of historical science, since industrial revolution itself was a historical moment in modern economic society and in the forming of modern capitalistic culture. If clothing culture had been developed in close relation to social culture. industrial revolution which gave a base for modern capitalistic culture, would be a birth of modern clothing as well as a moment for modernization of western clothing. As it takes for granted that industrial revolution, historical phenomenon is a developmental base of modern clothing culture. This study tried to enlighten the origin of modern clothing culture phenomenon with investigation of industrial revolution as a historical moment in modern clothing culture through documental study. Historian's point of view and method of studying are important when we investigate the clothing phenomenon. Although culture phenomenon of industrial revolution has been evaluated usually through socialogical aspect, studying for clothing culture phenomenon must be carried out on aethetical as well as well as sociological aspect, on account of dualism of clothing, as it is social and artistic nature. In 19th century, there were technical improvement, changing patterns of production, changing social relation and beginning of mass culture. At the same time clothing culture phenomenon was changed in relation to modern capitalistic society. The findings of the study could be summarized as follows. 1. Technical improvement in textile industry and fitting process brought about mechanization of clothing industry. 2. Appearance of popular clothing culture made it easy to spread to various classes of society. 3. Development of transportation system and communication channel made it internationalization of western clothing. 4. Recognition of importance in functional style of clothing. 5. The pursuit of modern aesthetics made rapid changing mode of clothing. Above distinctive features of modern clothing culture were derived from by-product of machinary culture, mass culture, internationalism, rapidly changing mode of various culture during industrial revolution. Industrial revolution was a change of the material world as well as in industry owing to machine advent, then the culture part that displayed directly these changes was the plastic arts of living that mould the material. The problem of clothing construction caused by industrial revolution was solved by pursuing the functional aesthetics. Clothing phenomenon as a process of value transfer participates mass culture in closs relation to general change of various culture caused by industrial revolution. Therefore western clothing gained the qualities of modern culture, condensed as function, and popularity in the process of modernization.

• 비파괴검사학회지
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• 제25권2호
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• pp.117-126
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• 2005

[ $AgGaS_2$ ] 단결정 박막을 수평 전기로에서 합성한 $AgGaS_2$ 다결정을 증발원으로하여, hot wall epitaxy(HWE) 방법으로 증발원과 기판 (반절연성 -GaAs (100))의 온도를 각각 $590^{\circ}C,\;440^{\circ}C$로 고정하여 성장하였다. 이때 단결정 박막의 결정성은 광발광 스펙트럼과 이중결정 X-선 요동곡선 (DCRC)으로 부터 구하였다. $AgGaS_2$의 광흡수 스펙트럼으로부터 구한 온도에 의존하는 에너지 밴드갭 $E_g(T)$는 Varshni. 공식에 fitting한 결과 $E_g(T)=2.7284 eV-(8.695{\times}10^{-4}eV/K)T^2/T(T+332K)$를 잘 만족하였다. 성장된 $AgGaS_2$, 단결정 박막을 Ag, Ga, S분위기에서 각각 열처리하여 10K에서 photoluminescience(PL) spectrum을 측정하여 점 결함의 기원을 알아보았다. PL 측정으로부터 얻어진 $V_{Ag},\;V_s,\;Ag_{int}$, 그리고 $S_{int}$는 주개와 받개로 분류되어졌다. $AgGaS_2$ 단결정 박막을 Ag분위기에서 열처리하면 n형으로 변환됨을 알 수 있었다. 또한, Ca 분위기에서 열처리하면 열처리 이전의 PL스펙트럼을 보이고 있어서, $AgGaS_2$ 단결정 박막에서 Ga은 안정된 결합의 형태로 있기 때문에 자연 결함의 형성에는 관련이 없음을 알았다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 1999년도 제17회 학술발표회 논문개요집
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• pp.162-162
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• 1999

초고주파 집적회로의 핵심소자로 각광을 받고 있는 GaAs MESFET(MEtal-emiconductor)은 게이트 형성 공정이 가장 중요하며, WNx 내화금속을 이용한 planar 게이트 구조의 경우 임계전압(Vth:threshold voltage)의 균일도가 우수할 뿐만 아니라 특히 Side-wall을 이용한 self-align 게이트는 소오스 저항을 줄일 수 있어 고성능의 소자 제작을 가능하게 한다.(1) 본 연구의 핵심이 되는 Side-wall을 형성하기 위하여 PECVD법에 의한 SiOx 박막을 증착하고, 건식식각법을 이용하여 SiOx side-wall을 형성하였다. 이 공정을 이용하여 소오스 저항이 낮고 임계전압의 균일도가 우수한 고성능의 self-aligned gate MESFET을 제작하였다. 3inch GaAs 기판상에 이온주입법에 의한 채널 형성, d.c. 스퍼터링법에 의한 WNx 증착, PECVD법에 의한 SiOx 증착, MERIE(Magnetic Enhanced Reactive Ion Etcing)에 의한 Side-wall 형성, LDD(Lightly Doped Drain)와 N+ 이온주입, 그리고 RTA(Rapid Thermal Annealing)를 사용하여 활성화 공정을 수행하였다. 채널은 40keV, 4312/cm2로, LDD는 50keV, 8e12/cm2로 이온주입하였고, 4000A의 SiOx를 증착한 후 2500A의 Side-wall을 형성하였다. 옴익 접촉은 AuGe/Ni/Au 합금을 이용하였고, 소자의 최종 Passivation은 SiNx 박막을 이용하였다. 제작된 소자의 전기적 특성은 hp4145B parameter analyzer를 이용한 전압-전류 측정을 통하여 평가하였다. Side-wall 형성은 0.3$\mu\textrm{m}$ 이상의 패턴크기에서 수직으로 잘 형성되었고, 본 연궁에서는 게이트 길이가 0.5$\mu\textrm{m}$인 MESFET을 제작하였다. d.c. 특성 측정 결과 Vds=2.0V에서 임계전압은 -0.78V, 트랜스컨덕턴스는 354mS/mm, 그리고 포화전류는 171mA/mm로 평가되었다. 특히 본 연구에서 개발된 트랜지스터의 게이트 전압 변화에 따른 균일한 트랜스 컨덕턴스의 특성은 RF 소자로 사용할 때 마이크로 웨이브의 왜곡특성을 없애주기 때문에 균일한 신호의 전달을 가능하게 한다. 0.5$\mu\textrm{m}$$\times$100$\mu\textrm{m}$ 게이트 MESFET을 이용한 S-parameter 측정과 Curve fitting 으로부터 차단주파수 fT는 40GHz 이상으로 평가되었고, 특히 균일한 트랜스컨덕턴스의 경향과 함께 차단주파수 역시 게이트 바이어스, 즉 소오스-드레스인 전류의 변화에 따라 균일한 값을 보였다. 본 연구에서 개발된 Side-wall 공정은 게이트 길이가 0.3$\mu\textrm{m}$까지 작은 경우에도 사용가능하며, WNx self-align gate MEESFET은 낮은 소오스저항, 균일한 임계전압 특성, 그리고 높고 균일한 트랜스 컨덕턴스 특성으로 HHP(Hend-Held Phone) 및 PCS(Personal communication System)와 같은 이동 통신용 단말기의 MMICs(Monolithic Microwave Integrates Circuits)의 제작에 활용될 것으로 기대된다.