• 한국지구과학회지
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• 제31권3호
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• pp.288-299
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• 2010

본 연구는 과학적 소양은 과학적 지식의 획득과 과학적 담화에 참여할 수 있는 언어적 능력을 통하여 길러진다는 전제하에 대기 중의 물의 상태변화에 관한 학생 글에서 나타나는 의미관계와 과학 언어적 특징을 알아보았다. 중학교 3학년 학생 67명이 참여하여 일상생활에서 흔히 경험할 수 있는 현상과 학교과학교육에서 체계적으로 배우는 현상 에 관한 두 개의 서술형 문항에 대한 글을 작성하였다. 연구의 결과 학생들은 '이슬점' 같은 생소한 용어뿐만 아니라 '수증기', '김' 등과 같은 친숙한 용어에 대해서도 잘못된 의미관계를 형성하고 있었고, 학교과학 교육보다 일상의 경험에서 형성된 지식에서 옳은 의미관계와 잘못된 의미관계 모두 더 많이 나타났다. 일상의 과학적 현상에 대해서는 행위와 절차를 중심으로 한 서술 양상이, 학교 교육에 의해 접하게 된 현상에 대해서는 전문용어와 명사구의 사용 양상이 보였다. 본 연구를 통하여 경험에 기초한 자발적 과정은 풍부한 의미관계 형성에, 형식적이고 이론적인 과정은 명사화를 중심으로 한 전문적이고 추상적인 서술의 측면에서 과학적 언어 능력 발달에 기여함을 알 수 있었다.

• 한국인쇄학회지
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• 제12권1호
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• pp.43-55
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• 1994

To investigate relations between Grain-shape of plate and Dot-Gain in the lithography, Printing plates were made by Mechanical Grain, Brush Grain and Electrolytic Grain method.Fine multi-grain by electrolytic method of them resulted in less Dot-grain on the paper, more damping water on the none image part of printing plate.

• 한국산림과학회지
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• 제63권1호
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• pp.28-34
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• 1984

본연구(本硏究)는 몇 종(種)의 침엽수(針葉樹)의 지엽(枝葉)에 있어서 P-V 곡선법(曲線法)에 의해 얻은 수분특성인자(水分特性因子)와 기공폐쇄작용(氣孔閉鎻作用)과의 관계(關係)를 측정고찰(測定考察)한 것으로 그 결과(結果)는 다음과 같다. 1. P-V 곡선법(曲線法)에 의해 구(求)한 초기원형질리점(初期原形質離點)의 water potential 값과 완전기공폐쇄점(完全氣孔閉鎻點)의 water potential 값은 거의 일치(一致)하였다. 2) 완전기공폐쇄점(完全氣孔閉鎻)는 잣나무 -21 bar(음엽(陰葉) -17 bar), 리기다 -20 bar, 소나무 -22 bar, 일본잎갈나무 -24 bar 전후(前後)에서 일어났다. 상대함수율(相對含水率)로 나타내면 잣나무 85%(음엽(陰葉) 82%), 리기다 77%, 소나무 85%, 일본잎갈나무 70% 전후(前後)에서 완전기공폐쇄(完全氣孔閉鎻)가 일어났다. 3. 초기기공폐쇄(初期氣孔閉鎻)는 잣나무 -14 bar(음엽(陰葉) -12 bar), 리기다 -10 bar, 소나무 -15 bar, 일본잎갈나무 -6 bar 전후(前後)에서 일어났다. 상대함수율(相對含水率)로 나타내면 잣나무 90%, 리기다 93%, 소나무 90% 일본잎갈나무 93% 전후(前後)에서 초기기공폐쇄(初期氣孔閉鎻)가 일어났다. 4. leaf conductance가 증가(增加)함에 따라 팽압(膨壓)은 증가(增加)하며, 상대함수율(相對含水率)이 증가(增加)함에 따라 팽압(膨壓)은 직선적(直線的)으로 증가(增加)하였다.

• 생태와환경
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• 제41권4호
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• pp.512-518
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• 2008

This study were to evaluate trophic conditions, N : P ratios, and empirical relations of chlorophyll (CHL) systematically using TN, TP, and CHL values in agricultural reservoirs and drinking water supplying dams. During the study, nutrients and CHL varied depending on seasonal conditions and types of the reservoirs, but most reservoirs were diagnozed as eutrophic to hypertrophic. Mass ratios of TN : TP averaged 93.1 (range: $0.68{\sim}1342$) and about 96.6 % of the total observations (n=516) was > 17 in the N : P ratios. This result suggests that P was a potential factor limiting algal growth in the entire reservoir. Thus, TN : TP ratios were a function of phosphorus rather than nitrogen. Regression analysis of log-transformed N : P ratios against TP in DWDRs and ARs showed that ratios were linearly declined with an increase of TP ($R^2$>0.66; p<0.001). Seasonal mean CHL was minimum ($4.3{\mu}g\;L^{-1}$, range: $0.1{\sim}39.7{\mu}g\;L^{-1}$) in premonsoon, and was similar between the monsoon and postmonsoon. In contrast, one of the tremendous features was that values of CHL was greater in the ARs than DWDRs. Thus, the spatial and temporal patterns in CHL were similar to those of TP but not TN. Empirical models of CHL-TP showed that CHL variation could explain average 15.3% and 11.3% in DWDRs and ARs, respectively. Seasonal analysis of empirical models showed that CHL-TP relations were stronger in postmonsoon than those of premonsoon and monsoon.

• 물과 미래
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• 제10권1호
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• pp.71-77
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• 1977

한 유역의 하천형태학적 특성은 유역의 강수-유출 관계해석에 중요한 영향을 미치며 이의 양적 서술은 유역의 물리특성 구명에 필수적인 것이라 하겠다. 본 연구에서는 금강의 3대 지류중의 하나인 갑천수계에 대해 Horton-Strahler의 방법에 의해 형태학적 특성만을 고찰하였으며 대체로 Horton의 법칙에 따라 수계조직이 발달되어 있음이 판명되었다. 본 연구에서 다룬 주 내용은 Horton의 하천 차수와 하천수, 평균하천연장 및 경사간의 관계와 누가하천연장-유역면적관계, 상대고도-상대면적관계, 비례하천차수-배수면적관계 등으로서 이들 형태학적 특성변수와 유량간의 상관성은 갑천유역내에 유량측점이 전혀 없어 분석이 불가능하였다.

• 한국산림과학회지
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• 제61권1호
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• pp.8-14
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• 1983

수목(樹木)에 있어서 내건성(耐乾性)의 크기를 진단(診斷)하기 위하여 P-V 곡선법(曲線法)에 의해 얻은 잣나무와 젓나무지엽(枝葉)(shoot)의 내적(內的) 수분특성인자(水分特性因子) ${\pi}_o$, ${\pi}_p$, $E_{max}$, $N_s/DW$, $V_o/W_s$, $RWC_{(tlp)}$ 등의 계절변화(季節變化)를 측정고찰(測定考察)하였다. 그 결과(結果)는 다음과 같다. 1) 잣나무지엽(枝葉)의 최대포수시(最大飽水時)의 침투압(浸透壓) ${\pi}_o$는 -1.2~-1.6 MPa, 젓나무지엽(枝葉)의 ${\pi}_p$는 -1.4~-1.7 MPa의 계절변화(季節變化)를 나타냈다. 2) 초기원형질분리점(初期原形質分離點)에 있어서 잣나무지엽(枝葉)의 침투압(浸透壓) ${\pi}_p$는 -1.8~-2.1MPa, 젓나무지엽(枝葉)의 ${\pi}_p$는 -1.6~-2.1MPa의 계절변화(季節變化)를 나타냈다. 3) 초기원형질분리점(初期原形質分離點)에 있어서 잣나무지엽(枝葉)의 상대함수율(相對含水率) $RWC_{(tlp)}$는 70~77%, 젓나무지엽(枝葉)의 $RWC_{(tlp)}$는 69~85%의 계절변화(季節變化)를 나타냈다. 4) 최대팽창시(最大膨壓時)의 잣나무지엽세포군(枝葉細胞群)의 탄성계수(彈性係數) $E_{max}$는 2.2~6.3 MPa, 젓나무의 $E_{max}$는 3.1~7.9 MPa의 계절변화(季節變化)를 나타냈다. 5) 잣나무지엽(枝葉)의 건물중(乾物重)에 대한 osmol 수(數) $N_5/DW$는 0.5~1.3, 젓나무지엽(枝葉)의 경우는 0.3~1.0의 계절변화(季節變化)를 나타냈다. 6) 잣나무지엽(枝葉)의 총함수량(總含水量)(symplasmic과 apoplastic water의 합계(合計))에 대한 총침투수량(總浸透水量) $V_o/W_s$는 55~65%, 젓나무지엽(枝葉)의 $V_o/W_s$는 40~65%의 계절변화(季節變化)를 나타냈다. 이상(以上)의 ${\pi}_o$, ${\pi}_p$, $E_{max}$, $N_s/DW$, $V_o/W_s$, $RWC_{(tlp)}$값의 특성(特性)을 고찰(考察)할 때 젓나무지엽(枝葉)이 잣나무지엽(枝葉)보다 내건성(耐乾性)이 약간 강한 수종(樹種)임을 알았다.

• 한국실내디자인학회논문집
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• 제38호
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• pp.258-265
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• 2003

The design of space, which focuses on human senses and perception, has become more prominent. It can be understood as the space needed for a field of experience. Phenomenological attitude focuses on the relations between human in the context of their environment. The experiences generated were used as a method of design. The method guides a formation of active space through phenomenological experience in interior space as well as architecture. To stimulate a phenomenological sensitive experience, the parameters for certain experiences were connected to the five senses, finally creating a concrete space. Water, light, air, vapor, and earth as architectural media are connected to the five senses and lead to intermediation from abstract to actual. In particular, water is deeply rooted in peoples subconsciousness and stimulates our instincts. Using water by effectively combining its symbols and physical characteristics will be a method to reinforce the experience with a given space. This study will examine the need for space experience and characteristics of water as an essential elements for perception experience and present possible experimental design.

• 물과 미래
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• 제14권4호
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• pp.27-34
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• 1981

The design flow of the urban strom drainage systems has been assessed largely on a basis of empirical relations between rainfall and runoff, and the rational formula has been widely used for the cities in our country. In order to estimate it more accurately, the urban runoff simulation model based on the RRl method has been developed and applied to the sample basin in this study. The rainfall hyetograph of the design stromfor the design flow has been obtained by the determination of the total rainfall and the temporal distributions of that rainfall. The total rainfall has been assessed from the empirical formula of rainfall intensity and the temporal distribution of that rainfall determined on the basis of Huff's method from the historical rainfall data of the basin. The virtual inflow hydrograph to each inlet of the basin has been constructed by computing the series of discharges in each time increment, using design strom hyetograph and time-area diagram. The actual runoff hydrograph at the basin outlet has been computed from the virtual inflow hydrographs by developing a relations between discharge and storage for the watershed. The discharge data for verification of the simulated runoff hydrograph are not available in the sample basin and so the sensitivity analysis of the simulation model has not been possible. The peak discharge for the design of drainage systems has been estimated from the computed runoff hydrograph at the basin outlet and compared to thatl obtained form the rational formula.

• Computers and Concrete
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• 제20권4호
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• pp.449-459
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• 2017

Fresh and hardened behaviors of a new hybrid fiber (steel fiber, polyvinyl alcohol fiber and calcium carbonate whisker) reinforced cementitious composites (HyFRCC) with admixtures (fly ash, silica fume and water reducer) have been studied. Within the limitations of the equipment and testing program, it is illustrated that the rheological properties of the new HyFRCC conform to the modified Bingham model. The relations between flow spread and yield stress as well as flow rate and plastic viscosity both conform well with negative exponent correlation, justifying that slump flow and flow rate test can be applied to replace the other two as simple rheology measurement and control method in jobsite. In addition, for the new HyFRCC with fly ash and water reducer, the mathematical model between the rheological and mechanical properties conform well with the quadratic function, and these quadratic function curves are always concave upward. Based on mathematical analysis, an optimal range of rheology/ flowability can be identified to achieve ideal mechanical properties. In addition, this optimization method can be extended to PVA fiber reinforced cement-based composites.

• 한국약용작물학회지
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• 제20권1호
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• pp.36-41
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• 2012

This study was carried out to establish a proper cultivation site and diagnose the drought tolerance of Pleurospermum camtschaticum, Cirsium setidens and Parasenecio firmus leaves by using pressure-volume curves. The result of ${\Psi}_o^{sat}$ and ${\Psi}_o^{tlp}$ were lower in Pleurospermum camtschaticum leaves. On the other hand, it appeared that $E_{max}$ of Pleurospermum camtschaticum was approximately six times higher than that of Parasenecio firmus. The values of $RWC^{tlp}$ is all above 88% showing that the function of osmoregulation is somewhat better, and Vo/DW, Vt/DW, Ns/DW of Pleurospermum camtschaticum leaves were approximately 2~4 times Lower than other ones. Thus, responses to water relations of Pleurospermum camtschaticum, Cirsium setidens and Parasenecio firmus such as ${\Psi}_o^{sat}$, ${\Psi}_o^{tlp}$, $E_{max}$, ${\Psi}_{P,max}$, $RWC^{tlp}$ were shown that the Pleurospermum camtschaticum leave was higher drought tolerance than Cirsium setidens and Parasenecio firmus leaves.