• 한국작물학회지
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• 제63권2호
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• pp.120-130
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• 2018

Improvement in rice grain yield has been approached by means of genetic amendment, cultural management, and environmental adaptation. Subjecting the plant during the grain filling period to an appropriate environment plays a key role in achieving a high grain yield in temperate rice. Field experiments were conducted for two consecutive years with two planting times to assess the relations among grain filling traits, loss of leaf activity during the ripening period, and the grain yield of temperate japonica rice with wide environmental variation. Higher grain yields were attained in 2017 than in 2016 and with late planting than with early planting. The high grain yield accompanied a comparatively lesser increase in grain weight at the early filling stage but more gain in grain weight occurred during the late filling stage. Final grain weight correlated positively with grain filling duration but negatively with grain filling rate. Extended grain filling duration was associated with higher cumulative temperature and cumulative solar radiation for an effective grain filling period. The reduction in SPAD value ${\times}$ leaf dry weight from heading to harvest significantly correlated with final grain dry weight in a positive manner. No significant relation was found between grain filling duration and the decrease in SPAD value ${\times}$ leaf dry weight during the grain filling period. The results suggest that grain filling duration and loss of leaf activity during ripening independently contribute to environmentally induced yield improvement in temperate japonica rice.

• Restorative Dentistry and Endodontics
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• 제4권1호
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• pp.11-16
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• 1978

This experimental study was made to investigate the effect of the "Hi-Pol" composite resin on the human dental pulp. 38 cavities of healthy permanent teeth were divided into 5 groups which were used as experimental materials. Group 1: Zinc Oxide-Euginol paste was applied to the cavities as controls $\cdots\;\cdots8$ cases Group 2: "Hi-Pol"*filling with Dycal** base $\cdots\;\cdots9$ cases Group 3: "Hi-Pol" filling without Dycal base $\cdots\;\cdots9$ cases Groud 4: Adaptic*** filling with Dycal base $\cdots\;\cdots6$ cases Group 5: Adaptic filling without Dycal base $\cdots\;\cdots6$ cases The treated teeth were extracted after 1 week, 2 weeks, 3 weeks and 4 weeks and processed for histological study. The results obtained from this experimental study were as follows; 1. The controls applied zinc oxide-eugenol showed the minimal pulp response and group 3 and group 5 showed the most severe pulp response. 2. In group 3 and group 5, the severity of pulp response increased in intensity according to the time elapsed. 3. In group 2 and group 4, the mild pulp response was found in earlier stage and the repairing process could be observed in later stage. * Boo-Pyung Co., Korea ** L. D. Caulk Co., Milford, Del. 19963 *** Johnson and Johnson Co., New Brunswick, NJ 08903.

• 한국작물학회지
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• 제28권3호
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• pp.368-373
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• 1983

본 시험은 1978년부터 1979년까지 2개년간 수원과 광주에서 소맥 “조광”을 공시하여 파종기를 달리하였을 때 등숙기간중 립중의 경시적인 증가양상과 품질의 변이에 관하여 등숙기간별로 추적조사한 바 그 결과를 요약하면 다음과 같다. 1. 출수기는 지역간에는 수원에서 파종기차이에서는 적기파종에서 빨랐으나 년차간에는 차이가 없었으며 출수까지의 일수는 지역 및 파종기에 따라 변이가 비교적 커서 수원에서 225-207일, 광주는 192-176일이 소요되었다. 2. 등숙전기의 립중은 광주에서 보다 수원에서 무거웠으나 최종 립중은 반대로 광주에서 높았다. 3. 등숙일수는 년차변이가 커서 수원에서 적기파종한 경우는 43-49일, 광주는 44-51일이었으며 만기파종은 동일지역내에서 적기파종에 비해 1-4일이 단축되었다. 4. 제분율은 지역간에는 광주에서, 파종기간에는 적기파종에서 다소 높았으며 등숙일수에 따라서는 등숙이 진전됨에 의해 증가하여 만기파종에서는 출수후 45일에 최대가 되었으나 적기파종에서는 45일이후까지 경미한 증가경향을 보였다. 5. 단백질함량과 심전가는 제분율과는 반대로 고온하에서 등숙이 이루어진 북부지방에서, 파종기에 따라서는 만기파종에서 높았으며 등숙기간별로는 일양적인 경향이 없었다.

• 한국작물학회지
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• 제36권1호
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• pp.34-40
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• 1991

본 시험은 대맥 등숙기간중 급속한 온도상승과 고온건조 및 과습 등 불량환경으로 맥체가 급격히 노화되어 충분히 등숙되지 않은 상태에서 성숙이 이루어지기 때문에 우리나라의 대맥은 품질이 불량할 뿐만 아니라 수량성도 외국에 비해 떨어지고 있는 실정이다. 따라서 등숙기의 엽신노화와 동화산물의 전류특성과의 관계를 구명하여 등숙향상을 위한 품종 육성 선발의 기초 자료로 이용코자 실시하였던바, 결과를 요약하면 다음과 같다. 1. 등숙일수 경과에 따른 엽신의 생엽수 및 노화속도는 품종에 따라 큰 차이가 있었다. 2. 입출전 및 동화물질의 전류속도는 엽신의 노화가 빠른 품종군이 늦은 품종군에 비해 빠른 것으로 나타났다. 3. 엽위 및 기관별로 $^{14}$ C 물질의 전류 양상을 본 결과, 등숙초기에는 노화가 빠른 품종군은 산위엽(지엽, 2엽)과 하위엽 ( 3, 4, 5엽)에 흡수된 $^{14}$ C의 량이 이삭으로 전류되는 비율이 비슷하였으나 등숙이 진전되면서 상위엽에 흡수된 $^{14}$ C은 전류가 급격히 이루어지나 하위엽은 반대의 경향이고, 노화가 늦은 품종군은 등숙초기에는 하위엽의 전류속도가 월등히 높고 하위엽은 낮으나 등숙이 진전되면서 반대의 양상으로 나타났다. 4. 경엽에 흡수된 $^{14}$ C이 종실로 정류되는 양상과 입충전속도가 엽신의 노화속도 조만 품종군별로 일치하는 경향이었다. 5. 광합성 속도는 등숙중기까지는 엽신노화가 빠른 품종이 높았으나 중기후는 낮았다. 6. 종실수량은 엽신의 노화속도가 빠른 품종군이 다소 높은 경향이었다.

• Restorative Dentistry and Endodontics
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• 제13권1호
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• pp.41-52
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• 1988

The purpose of this study was to investigate the pulpal responses to acid etching of dentine. Total 72 class V cavaties' were prepared on the healthy permanent teeth from 6 dogs, and were divided into 4 groups. These were filled with filling materials after acid etching with each etchant for 1 min. Control group ; ZOE filling without acid etching. Group 1: Zinc Oxide-Eugenol cement filling. Group 2: Drying with hot air and Zinc oxide-Eugenol cement filling. Group 3: Scotchbond application and silux filling. Group 4: Silux filling. The dogs were sacrificed after 1 week, 2 weeks, 3 weeks, 4 weeks, 5 weeks and 6 weeks following operation. The specimens were routinely prepared and stained with Hematoxylin and Eosin. Followings were the results obtained through microscopic examination. 1. There was mostly severe pulpal responses in case of Silux filling after acid etching of dentine. 2. The pulpal responses of Silux filling after acid etching and application of Scotch bond group were more severe compared to Zinc Oxide-Eugenol cement filling group, but less severe compared to Silux filling group after acid etching of dentine. 3. The pulpal responses of Zinc Oxide-Eugenol cement filling group were similar to those of Zinc Oxide-Eugenol cement filling after drying with hot air group. 4. There was slight pulpal responses in early stage in case of Zinc Oxide-Eugenol cement filling group, but recovered to normal state soon after.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2005년도 춘계학술대회 논문집
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• pp.43-46
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• 2005

Micro molding technology is a promising mass production technology for polymer based microstructures. Mass production technologies such as the micro injection/compression molding, hot embossing, and micro reaction molding are already in use. In the present study, we have developed a numerical analysis system to simulate three-dimensional non-isothermal cavity filling for hot embossing, with a special emphasis on the free surface capturing. Precise free surface capturing has been successfully accomplished with the level set method, which is solved by means of the Runge-Kutta discontinuous Galerkin (RKDG) method. The RKDG method turns out to be excellent from the viewpoint of both numerical stability and accuracy of volume conservation. The Stokes equations are solved by the stabilized finite element method using the equal order tri-linear interpolation function. To prevent possible numerical oscillation in temperature Held we employ the streamline upwind Petrov-Galerkin (SUPG) method. With the developed code we investigated the detailed change of free surface shape in time during the mold filling. In the filling simulation of a simple rectangular cavity with repeating protruded parts, we find out that filling patterns are significantly influenced by the geometric characteristics such as the thickness of base plate and the aspect ratio and pitch of repeating microstructures. The numerical analysis system enables us to understand the basic flow and material deformation taking place during the cavity filling stage in microstructure fabrications.

• 한국자동차공학회논문집
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• 제2권6호
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• pp.110-116
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• 1994

In this research, the tensile strength of molded parts and pressure distribution were analyzed to study the cavity filling stage and packing stage in injection molding. The measurement of cavity pressure was obtained by a data acquisition system with the installation of transducers in the cavity. Molded parts were tested by a universal testing machine to obtain the tensile strength. For the experimental work, the tensile strength of molded parts increased with longer packing time and exact freezing time of the gate was obtained by a cavity pressure curve. In addition, the effect of packing did not occur and tensile strength was almost constant after early 1.5 sec of the freezing time of gate. Density tended to be higher about 0.2% due to a larger degree of mold temperature and melt temperature. Also, changing pressure in the cavity was effectively sensed. Thereafter, the possibility of the development of pattern recognition expert system was confirmed on the basis of the experimental results.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 춘계 학술발표회
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• pp.199-209
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• 2009

The movement of the caisson used to construct a wharf front can affect functional performance of the port. Sequential movement of caissons at each stage of the construction is essential in the overall design as well as the stability of the port. It is common that back-analysis using the previous measurement is performed to predict the caisson movement, while there is no intensive study on sequential movement of the caissons according to the construction stage. In the study, we analyzed the pattern of the movement of caissons as a port is constructed. To simulate the construction of the port, the finite element method (FEM) is employed. The computed result shows that the caisson moves differently at each construction stage. When the caisson is being installed, the displacement of the caisson takes place mainly in vertical direction. In next stage of filling rocks behind the caisson, the top of the caisson move toward shore, while the bottom moves toward sea, thus rotating the caisson. The maximum rotation of the caisson takes place in the stage of filling rocks behind the caisson.

• 한국작물학회지
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• 제60권3호
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• pp.273-281
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• 2015

벼 등숙기간 및 등숙기 기간별 기온과 일조시간이 쌀 품질 특성에 미치는 영향을 알아보기 위하여 전국 8개도 24개 지역에서 고품질 벼 11품종을 이용하여 2013-2014년에 시험한 결과는 다음과 같다. 1. 품종, 지역 및 연차별 시험성적을 모두 합하였을 때, 출수기, 출수 후 40일간 평균기온 및 일조시간의 범위는 각각 7월 23일~9월 4일, $18.8{\sim}26.4^{\circ}C$, 3.9~8.0시간/일이었다. 2. 성적을 모두 합하였을 때, 특성별 범위는 등숙비율 74.2~97.9%, 현미 천립중 19.6~26.1 g, 완전미 비율 61.4~98.5%, 완전미 수량 276~701 kg/10a, 쌀 단백질 4.8~8.3%, Toyo Mido Meter 값 66.1~91.5였다. 3. 완전미 비율, 완전미 수량, 쌀 단백질 및 Toyo Mido Meter 값은 출수 후 40일간의 등숙 최적온도인 $22.6^{\circ}C$보다 낮은 온도에서 높아졌으며, 쌀 외관품위와 밥맛을 고려한 출수 후 40일간의 최적 일조시간은 6.0~6.1시간/일로 평가되었다. 4. 쌀 단백질은 출수 후 40일간의 평균기온 및 일조시간과 유의한 관계를 보인 품종이 전체 11품종 중 각각 8개와 9개로, 다른 특성에 비해 많았다. 5. 쌀 단백질은 등숙 초기의 평균기온 및 등숙 초 중기의 일조시간에, 완전미 비율은 등숙 초기의 평균기온 및 일조시간에 상대적으로 더 큰 영향을 받았다.

• 한국기계가공학회지
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• 제3권4호
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• pp.95-100
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• 2004

Plastics is used to produce precise parts with an inclusion of a reinforcement material such as glass fiber or carbon fiber to improve the dimension accuracy. The plastic goods can be produced with inaccurate dimensions, low mechanical strength, or residual stress due to the over packing of cavity inside, if the filling balance of melt resin is not accomplished. To overcome this problem, it is necessary to design the runner system with the geometrical balance at the mold design stage. However, even if the balanced runner system is achieved, a severe filling imbalance is observed practically in a multi-cavity mold. In this study, experiments were performed with Taguchi method to achieve the filling balance in multi-cavity mold with a symmetric runner system, by the use of pure PA and PA with glass fiber 33%. The experimental results were investigated to understand the effect of related molding factors on the filling imbalance for two resins.