• 제목/요약/키워드: fundamental relation

검색결과 448건 처리시간 0.02초

ERBO 혼입율 및 혼입시기 변화에 따른 고강도 모르타르의 자기수축 특성분석 (Analysis of Autogenous Shrinkage Properties of High Strength Mortar in Relation to the Time and Rate of Mixing ERBO)

  • 김태우;백철;현승용;이제현;한민철;한천구
    • 한국건축시공학회:학술대회논문집
    • /
    • 한국건축시공학회 2017년도 춘계 학술논문 발표대회
    • /
    • pp.180-181
    • /
    • 2017
  • This study aims to analyze the high strength mortar's fundamental properties and autogenous shrinkage properties by taking into consideration the result of the previous study in which it was found that ERBO(Biodiesel) exercises greatest effect on the expansion effect of mortar, and changing the time and rate of mixing the ERBO. A total of five levels were set as experimental variables: the three levels of the rate of ERBO, 0, 0.5, 1.0%, and the two levels of the time of mixing the ERBO: first, adding the ERBO with the mixing water and mixing it before, and second, mixing it after the mortar is completely mixed. It was found that the rate of length change decreased as the rate of ERBO increased, and the rate of length change was lower when the ERBO was mixed sooner.

  • PDF

도시역 거수목의 잔존형태와 그 효용성에 관한 연구 (A Study on the Remnant Forms and Effects of Big Trees in an Urban Area)

  • 김용수;임원현
    • 한국조경학회지
    • /
    • 제24권3호
    • /
    • pp.14-28
    • /
    • 1996
  • Purposes of this study were to provide the basic information for the management policy for more preserve and refreshing Gusumok-big and old tree. Fundamental directions for the protection and application of Gusumok were suggested by comparing and analyzing present conditions and remnant forms of Gusumok as preserved tree in Kyung-ju and its function and the role of Gusumok according to the civilization and diference between past and present. The main results of the study are as follows ; There are 121 Gusumok which designated as a preserved tree in Kyung-ju. It is distributed all over the Kyung-ju city uniformly and located in the enterance or the center of a village having high interests of most of residents. in the course of a civilzation, the percintage of a loss of an urban Gusumok is higher than that of a rural Gusumok and its function is also changed so much. A modern function of Gusumok can be divided into a positive and negative one. A positive function is the offer of amenity and the place of receation, formation of culture and ragulation of micro climate. A negative function is of psycholosical and functional reversed function. having a close relation with our life, Gusumok offers an amenity place to our life to make us feel soft and comfortable as well as developes the quality of our life. Gusumok has an important meaning in mordern society in that it contibutes to our village being better to live by having a historical meaning and creating a symbolic culture and history.

  • PDF

OBSERV ATION OF MICRO-STRUCTURE AND OPTICAL PROPERTISE OF TITANIUM DIOXIDE THIN FILMS USING OPTICAL MMEHODS

  • Kim, S.Y.;Kim, H.J.
    • 한국표면공학회지
    • /
    • 제29권6호
    • /
    • pp.788-796
    • /
    • 1996
  • $TiO_2$ films prepared by RF magnetron sputtering, electron beam evaporation, ion assisted deposition (IAD) and sol-gel method are prepared on c-Si substrate and vitreous silica substrate respectively. From the transmission spectra of $TiO_2$ films on vitreous silica substrate in the spectral region from 190 nm to 900 nm, k($\lambda$) of $TiO_2$ is obtained. Using k($\lambda$) in the interband transition region the coefficients of the quantum mechanical dispersion relation of an amorphous $TiO_2$ and hence n($\lambda$) including the optically opaque region of above fundamental transition energy are obtained. The spectroscopic ellipsometry spectra of $TiO_2$ films in the spectral region of 1.5-5.0eV are model analyzed to get the film packing density variation versus i) substrate material, ii) film thickness and iii) film growth technique. The complex refractive index change of these $TiO_2$ films versus water condensation is also studied. Film micro-structures by SE modelling results are compared with those by atomic force microscopy images and X-ray diffraction data.

  • PDF

지방자치단체의 U-City 개발 동향 분석과 개발방향 (A Study on the Trends of the U-City Development and Its Direction in the Local Governments)

  • 임영택;최봉문
    • 한국콘텐츠학회논문지
    • /
    • 제6권1호
    • /
    • pp.126-136
    • /
    • 2006
  • 본 연구는 현재 지자체들이 추진하고 있는 U-City 개발의 추진현황과 U-City 개발이 전체 도시적 맥락에서 추진될 수 있도록 그 기본 방향을 제시하고자 하였다. 이는 지방자치단체들이 U-City 추진을 위한 기본 계획을 수립함에 있어서 그 기본 방향 정립에 기초적인 관점을 제시한다는 측면에서 의미가 있다. 이를 위해 본 연구는 우선 유비쿼터스(ubiquitous)의 개념, U-City 구현을 위한 관련기술, 중앙정부 차원에서 추진하고 있는 유비쿼터스 관련 정책, 그리고 각 지방자치단체에서 추진하고 있는 U-City 개발 현황에 대하여 파악하였다. 끝으로 지방자치단체들의 U-City 개발에 있어서 기존 도시와의 관계와 도시 구조적 맥락에서 그 방향을 제시하였다.

  • PDF

지지구조물과 부시스템으로 이루어진 계의 동적 특성 (Dynamic Characteristics of a System Composed of a Supporting Structure and Subsystems)

  • 이건명
    • 한국소음진동공학회논문집
    • /
    • 제26권4호
    • /
    • pp.406-411
    • /
    • 2016
  • 지지구조물 위의 부시스템으로 이루어진 계의 고유 진동수와 모드형을 근사적으로 구하는 식을 유도하였다. 이 계는 이산계로 모형화되었고, 부시스템의 질량은 지지구조물의 질량에 비하여 매우 작다고 가정하였다. 기본진동수는 지지구조물에 대응하고, 고차 진동수는 각각의 부시스템에 대응한다는 것이 밝혀졌다. 또한 지지구조물이 조화력에 의해 가진될 때 지지구조물과 부시스템의 진동 진폭 사이의 관계를 유도하였다.

제주연안 각망의 조석에 의한 어획량 변동 (Catch fluctuation of the rectangular set net according to the tide age in the coastal waters of Jeju)

  • 이창헌;최찬문
    • 수산해양기술연구
    • /
    • 제44권2호
    • /
    • pp.112-119
    • /
    • 2008
  • The fundamental data on the catch fluctuation in the rectangular set net according to the tide age were developed based on the catches recorded from the year 1986 to 2004 in the coastal waters of Hamdeok, Jeju. Total catch by the rectangular set net had a deep connection with the tide age. In particular, during increasing tide, total catch were reduced gradually from the neap tide to the high tide. As it turned out, the slope of total catch declined by degree and showed a correlation coefficient of determination of 0.76. On the contrary, in the case of decreasing tide, there was little sign of rise in total catch. In particular, large catch seemed to occur at the next tide to the neap tide. In the relation between the catch and the tide age, the level of the correlation coefficient chosen at $p{\leq}0.05$ decreased in the order rabbitfish(-0.84) and horse mackerel(-0.71), while the significance of other dominant species were not selected.

수면 열환경에 관한 연구 (II) -침구의 경량화에 따른 보온력- (Studies on the Thermal Environment in Sleeping (II) -Thermal Insulation Effect of Bedding on Lightweight-)

  • 성수광
    • 한국의류학회지
    • /
    • 제17권3호
    • /
    • pp.470-474
    • /
    • 1993
  • This study carried out to get some fundamental data for designing lightweight bedding. In This study, the wool blanket, polyester/cotton blended blanket and down quilt were manufactured with a varied materials, structural factors such as yam count, fabric density respectivelyarn. And also, the thermal insulation value of the bedding were measured by warmth retaining tester. In addition, this paper examines the influence of varying materials, structural factors and blanket layers on the thermal insulation effect of the bedding. The main results obtained from this study are as follow : 1. The design of lightweight blankets make an attempting with a varying materials and structural factors such as yam count, fabric densityarn. 2. Almost, the design of lightweight blankets for polyester/cotton blended blanket and down quilt make an attempting without reduction in thermal insulation values. 3. The 6 layers of blanket have less thermal insulation value than the 6 times of blanket for under a layer have. About 27~32% decrease is observed in thermal insulation value of blanket for under 6 layer. 4. The thermal insulation value and areal weight of blankets have a positive relation between the thermal insulation value(Y) and areal weight(X) is based on the following equation. wool blanket : Y = 1.0850X + 0.4188 (r = 0.9992) PIC blended blanket : Y = 0.8845X + 0.3034 (r = 0.9999)

  • PDF

자탈형 콤바인 탈곡부 설계요인(設計要因)의 적정화(適正化)를 위한 연구(I) -급동축(扱胴軸) 토오크 파형의 추정(推定)- (Optimizing the design factors of the head-fed type combine(I) -Estimation of the threshing drum torque curve-)

  • 남상일;정창주;호소카와 아키라
    • Journal of Biosystems Engineering
    • /
    • 제12권3호
    • /
    • pp.42-49
    • /
    • 1987
  • The threshing action of the head-fed type threshing unit occurs mainly by the impact between threshing tooth and grains. It may be therefore the most fundamental step to calculate the time and order of the occurrance of impact by the tooth for predicting the performance of threshing unit. The threshing teeth arrangement was defined by length and diameter of threshing dram, number of spiral arrays, number of threshing teeth by kind per one spiral array, number of windings of spiral array around the threshing drum, delay angle of impact line. The linear equations for locus of left and right margin of paddy bundle, spiral array, impact line on the development figure of the threshing drum were expressed by fastors of the threshing teeth arrangement. In the computer program, the teeth which inflict impact were searched successively along the impact line. Searching range and impact condition were defined by the relation between four linear equations. If the impacting tooth was found, time and the kind of threshing tooth was derived from the coordinate of the threshing tooth. At this time the unit torque curve was accumulated on the array of computer memory. At last the completed torque curve of threshing drum shaft was described on the computer screen. Remarkably the peack valae and fluctuation of torque curve was decreased by adopting the delay angle of impact line.

  • PDF

축류(軸流) 콤바인의 개발(開發)에 관(關)한 기초(基礎) 연구(硏究)(II) - 탈립과정(脱粒過程)의 수학적(數學的) 모형(模型) 개발(開發) - (Fundamental Studies on the Development of Axial-flow Combine(II) - Development of Mathematical Model of Threshing Process -)

  • 이승규;우종구;김성태
    • Journal of Biosystems Engineering
    • /
    • 제16권1호
    • /
    • pp.27-36
    • /
    • 1991
  • This study was carried out getting basic data for developing a new combine which is suitable for the cultivating situation in Korea or Southeast Asia. The relation of the amount of unthreshed grains and the axial displacement of crop in threshing process was attempted to formulate mathematically in a threshing chamber of axial-flow threshing unit. It was found that unthreshed grain is an exponetially-decaying functon of axial displacement of grains based on available data. Threshing experiments were performed to validate the mathematical model by changing various levels of pertinent variables for malting barley. Good correlation were obtained between the theoretical calculation and observed data for various test conditions, such as inclination, vane pitch, concave length, drum speed, feeding velocity, stream weight, moisture content. Therefore the model can be used for general purpose to find the amount of unthreshed grain if the mean rate of occurence of threshing of kernels(${\lambda}_{\tau}$) is properly calibrated considering some other operating conditions and crop conditions which are not involved in this analysis.

  • PDF

교원 정보화 연수 현황 및 활용 실태에 관한 연구 (A Study on the Teachers' ICT Training Status and Using Realities)

  • 김재현;백진희
    • 인터넷정보학회논문지
    • /
    • 제9권2호
    • /
    • pp.119-129
    • /
    • 2008
  • 교원의 정보 활용 능력 강화 사업은 교원의 정보화 연수, 정보통신기술 활용강화, 정보교육담당 교원 양성 방면에서 다양하게 진행되고 있고, 교원 정보화 연수가 점차적으로 확대되어 가고 있다. 따라서 본 연구에서는 급변하는 지식정보화사회에 대비하여 교원 정보화 연수의 전반적 상황을 파악하고, 연수를 통해 교수 학습과 담당 업무의 활용 정도에 얼마나 영향을 미치는지에 대한 교사들의 인식을 조사하고자한다. 또한, 교원 연수과정과 연수 후 교수학습 활동 및 담당업무와 관련된 ICT 활용도를 분석한다. 이를 근거로 교원정보화 연수 개선방안을 제안함으로써 근본적인 교육의 질 향상에 도움을 제공하고자 한다.

  • PDF