• 한국초전도ㆍ저온공학회논문지
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• 제16권4호
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• pp.71-77
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• 2014

For a long-term space mission, filling process of cryogenic liquid propellant is operated on a space vehicle in space. A vent process during transfer and filling of cryogenic propellant is needed to maintain the fuel tank pressure at a safe level due to its volatile characteristic. It is possible that both liquid and vapor phases of the cryogenic propellant are released simultaneously to outer space when the vent process occurs under low gravity environment. As a result, the existing filling process with venting not only accompanies wasting liquid propellant, but also consumes extra fuel to compensate for the unexpected momentum originated from the vent process. No-Vent Fill (NVF) method, a filling procedure without a venting process of cryogenic liquid propellant, is an attractive technology to perform a long-term space mission. In this paper, the preliminary experimental results of the NVF process are described. The experimental set-up consists of a 9-liter cryogenic liquid receiver tank and a supply tank. Liquid nitrogen ($LN_2$) is used to simulate the behavior of cryogenic propellant. The whole situation in the receiver tank during NVF is monitored. The major experimental parameter in the experiment is the mass flow rate of the liquid nitrogen. The experimental results demonstrate that as the mass flow rate is increased, NVF process is conducted successfully. The quality and the inlet temperature of the injected $LN_2$ are affected by the mass flow rate. These parameters determine success of NVF.

• 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.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2007년도 제28회 춘계학술대회논문집
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• pp.34-37
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• 2007

액체산소를 작동유체로 하여 추진제 공급배관에 대한 충진 및 대기 시험을 수행하였다. 추진제 공급 시스템은 추진제 탱크의 출구에 필터가 장착된 형상이다. 추진제의 충진이 완료된 후 대기 과정동안 액체산소의 증발과 이것이 시스템의 재순환 성능에 미치는 영향을 살펴보았다. 추진제의 충진 속도와 탱크 얼리지의 압력이 배관 내 액체산소의 상태에 영향을 미치는 것을 확인하였다. 필터의 장착 위치로 인해 대기 과정동안 배관 내부에서 geysering 현상은 발생하지 않았다.

• 한국토양비료학회지
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• 제6권2호
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• pp.95-105
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• 1973

IR667 계통(系統)(Suwon 213 및 214)과 장려품종(진흥(振興) 및 팔달(八達))의 수용기(受用器)(Sink) 및 급여기(給與器)(Source)의 크기와 그들간(間) 거리(距離), 동화산물의 형태(形態), 기상인자(氣象因子)와 관련(關聯) 수기(受器)(곡실(穀實))충전(充塡) 속도(速度)를 검토(檢討)하여 다음과 같은 결과(結果)를 얻었다. 1. IR667 계통(系統)은 장려 품종보다 최고수기충전속도(最高受器充塡速度)가 크고 빨리온다. 충전속도곡선(充塡速度曲線)의 양상(樣相)은 IR667 계(系)는 준봉형(峻峰型)을 장려품종은 구릉형(丘陵型)을 보인다. 2. 기상인자(氣象因子)는 충전곡선(充塡曲線)의 양상(樣相)에 큰 변화(變化)를 주지 못하는 것 같다. 3. 수기일급기간(受器一給器間) 기능거리(機能距離)(실거리(實距離)${\times}$각엽(各葉)의 생산기여율는 상위엽의존형(上位葉依存型)인 IR667 계(系)에서는 상위엽(上位葉)이 짧고 하위엽의존형(下位葉依存型)인 장려품중에서는 하위엽(下位葉)이 짧다. IR667의 상위엽의존성(上位葉依存性)이 유난히 짧은 제(第)1간장(稈長)(상부(上部)로부터)에 기인(基因)하는것 같다. 4. 간(稈)과 엽초의 유리당(遊離糖)/전분비(澱粉比)에 따라 IR667계(系)는 고당형(高糖型)으로 장려품종은 고전분형(高澱粉型)으로 분류(分類)되었으며 전이성(轉移性)(당(糖))과 비전이성(非轉移性) 동화산물(전분(澱粉))의 비(比)가 수기충전속도(受器充塡速度)와 관련되고 고당형(高糖型)이 생산효율이 높을 것으로 예상된다. 5. 군락구조(群落構造)의 각생산계층내의 균등도(均等度)가 클수록 곡실생산의 효율성이 높다는 가설(假說)을 제시(提示)하고 다수성(多收性) 및 안전성(安全性)과 관련(關聯)하여 검토(檢討)하였다. 6. 엽위별(葉位別) 엽신(葉身)의 N.P.K. 잔존률양상(殘存率樣相)이 진흥(振興)에서는 상부잔존형(上部殘存型)으로, IR667은 중앙부(中央部) 잔존형(殘存型)으로 구분(區分)되어 생산구조 보전형식(保存型式)의 원인(原因)으로 해석되었다. 7. 기관별(器管別) N.P.K 농도(濃度)와 함량분포비율(含量分布比率)에 의(依)하여 IR667은 엽초중심형으로 진흥(振興)은 엽신중심형(葉身中心型)으로 분류(分類)되었다. 8. 동일품종내(同一品種丙)에서 N.P간(間) N.P.K 각양분내(各養分內)에서 품종간(品種間) 수(穗)로의 전이율(轉移率)이 큰 경우 엽신잔존율(葉身殘存率)도 크다.

• Korean Chemical Engineering Research
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• 제54권6호
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• pp.723-733
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• 2016

반도체 배선 미세화에 의한 한계를 극복하기 위해 실리콘 관통 비아(through silicon via, TSV)를 사용한 소자의 3차원 적층에 대한 연구가 진행되고 있다. TSV 내부는 전해도금을 통해 구리로 채우며, 소자의 신뢰성을 확보하기 위해 결함 없는 TSV의 채움이 요구된다. TSV 입구와 벽면에서는 구리 전착을 억제하고, TSV 바닥에서 선택적으로 구리 전착을 유도하는 바닥 차오름을 통해 무결함 채움이 가능하다. 전해 도금액에 포함되는 유기 첨가제는 TSV 위치에 따라 국부적으로 구리 전착 속도를 결정하여 무결함 채움을 가능하게 한다. TSV의 채움 메커니즘은 첨가제의 거동에 기반하여 규명되므로 첨가제의 특성을 이해하는 연구가 선행되어야 한다. 본 총설에서는 첨가제의 작용기작을 바탕으로 하는 다양한 채움 메커니즘, TSV 채움 효율을 개선하기 위한 평탄제의 개발과 3-첨가제 시스템에서의 연구, 첨가제 작용기와 도금 방법의 수정을 통한 채움 특성의 향상에 관한 연구를 소개한다.

• 대한금속재료학회지
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• 제48권7호
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• pp.667-673
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• 2010

Copper filling into TSV (through-silicon-via) and reduction of the filling time for the three dimensional chip stacking were investigated in this study. A Si wafer with straight vias - $30\;{\mu}m$ in diameter and $60\;{\mu}m$ in depth with $200\;{\mu}m$ pitch - where the vias were drilled by DRIE (Deep Reactive Ion Etching) process, was prepared as a substrate. $SiO_2$, Ti and Au layers were coated as functional layers on the via wall. In order to reduce the time required complete the Cu filling into the TSV, the PPR (periodic pulse reverse) wave current was applied to the cathode of a Si chip during electroplating, and the PR (pulse-reverse) wave current was also applied for a comparison. The experimental results showed 100% filling rate into the TSV in one hour was achieved by the PPR electroplating process. At the interface between the Cu filling and Ti/ Au functional layers, no defect, such as a void, was found. Meanwhile, the electroplating by the PR current showed maximum 43% filling ratio into the TSV in an hour. The applied PPR wave form was confirmed to be effective to fill the TSV in a short time.

• Animal Bioscience
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• 제34권11호
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• pp.1776-1783
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• 2021

Objective: This project aimed to evaluate the effects of both different additives and filling methods on nutritive quality, fermentation profile, and in situ digestibility of whole plant corn silage. Methods: Whole plant corn forage harvested at 26.72% dry matter (DM) was chopped and treated with two filling methods, i) fill silos at one time (F1), ii) fill silos at three times (F3), packing samples into one/three silo capacity at the first day, another one/three capacity at the second day, then one/three at the third day, three replicates. For each replicate, samples were treated with three additives, i) control (CTRL, no additive), ii) Sila-Max (MAX, Ralco Nutrition Inc., Marshall, MN, USA), and iii) Sila-Mix (MIX, Ralco Nutrition Inc., USA). With three replicates of each secondary treatment, there were nine silos, 54 silos in total. Each silo had a packing density of 137.61 kg of DM/m3. All silos were weighed and stored in lab at ambient temperature. Results: After 60 d of ensiling, all items showed good silage fermentation under MAX filled one time or three times (p<0.01). Higher silage quality for all additives was obtained at filling one time than that filled three times (p<0.01). The highest DM and lowest DM loss rate (DMLR) occurred to MAX treatment at two filling methods (p<0.01); Digestibility of acid detergent fiber, neutral detergent fiber (NDF), and curde protein had the same results as silage quality (p<0.01). Yield of digestible DM and digestible NDF also showed higher value under MAX especially for filling one time (p<0.05). Conclusion: All corn silages showed good fermentation attributes (pH<4.0). The forage filled one time had higher silage quality than that filled three times (p<0.01). MAX with homofermentative lactic acid bacteria enhanced the lactic acid fermentation, silage quality and nutrient digestibility, and so improved the digestible nutrient yield.

• 아시안잔디학회지
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• 제9권3호
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• pp.173-185
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• 1995

Hydroseeding technique is a very popular method of revegetating slope areas through the control of soil erosion and stability by seeding grasses. This study was conducted to select turfgrass species and cultivars for hydroseeding. Experiment plots were established on various soil types and environmental conditions at Singar-Ansan high-way construction site. The investigation was designed in three cutting, one back-filling and other three spare sites with various seed mixtures. Results indicated that combinations of seed mixtures influenced seed germination and rates of surface cover. In a view of long term, vegetation shifts should be influenced by characters of slopes and micro-climate conditions. Hydroseeding did not show good results on rocky slope areas. Revegetation was only going on where there had soil. The combination of seed mixture with a higher rate of perennial ryegrass had relatively good revegetation with faster germination and seedling growth. Improved turf-type tall fescue Arid ⓡ and Falcon ⓡ seemed to have good environ-mental adaptation and drought tolerance. Wild or old type cultivars showed relatively slow green-up in spring and growth rates at the next year of seeding. For the harmonious landscaping with surrounding area, the combination of native grass mixture with cool-season grasses had good results. Slow and low revegetation rate at hack-filling site seemed to be caused by the poor development of capillary tubes in sub-soil. It was shown that a high correlation between seed germination and revegetation rate, and between three-month later coverage rate and final rate. The evaluation of coverage rate after three month seems to he acceptable to decide the accomplishment of hydroseeding results on rode side slopes.

• 오토저널
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• 제15권1호
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• pp.17-24
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• 1993

사출성형 문제는 열전달과 유체유동이 복합된 문제라고 할수 있다. 사출성형 공정은 충진(filling), 보압(packing) 및 냉각과정(cooling phase)으로 이루어 진다. 충진과정은 높은 점성의 Non-Newtonian유체가 몰드내의 캐버티로 사출됨으로써 이루어지며 플라스틱의 점성도는 플라스틱의 온도 및 유동속도와 관련이 크며 이 flow-rate는 점도와 더불어 변화한다. CAE 유동해석 프로그램은 유체의 흐름과 열전달을 이용하여 충진과정을 이해하는데 이용되고 있다. 본 고에서는 사출성형 과정 중 충진과정에 대한 컴퓨터 시뮬레이션과 그 적용사례에 대하여 살펴본다.

• Structural Engineering and Mechanics
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• 제81권2호
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• pp.243-258
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• 2022

In this paper, tensile behavior of joint filling has been investigated under experimental test and numerical simulation (particle flow code). Two concrete slabs containing semi cylinder hole were prepared. These slabs were attached to each other by glue and one cubic specimen with dimension of 19 cm×15 cm×6 cm was prepared. This sample placed in the universal testing machine where the direct tensile stress can be applied to this specimen by implementing a special type of load transferring device which converts the applied compressive load to that of the tensile during the test. In the present work, two different joint filling thickness i.e., 3 mm and 6 mm were prepared and tested in the laboratory to measure their direct tensile strengths. Concurrent with experimental test, numerical simulation was performed to investigate the effect of hole diameter, length of edge notch, filling thickness and filling length on the tensile behavior of joint filling. Model dimension was 19 cm×15 cm. hole diameter was change in four different values of 2.5 cm, 5 cm, 7.5 cm and 10 cm. glue lengths were different based on the hole diameter, i.e., 12.5 cm for hole diameter of 2.5 cm, 10 cm for hole diameter of 5 cm, 7.5 cm for hole diameter of 7.5 cm and 5 cm for hole diameter of 10 cm. length of edge notch were changed in three different value i.e., 10%, 30% and 50% of glue length. Filling thickness were changed in three different value of 3 mm, 6 mm and 9 mm. Tensile strengths of glue and concrete were 2.37 MPa and 6.4 MPa, respectively. The load was applied at a constant rate of 1 kg/s. Results shows that hole diameter, length of edge notch, filling thickness and filling length have important effect on the tensile behavior of joint filling. In fixed glue thinks and fixed joint length, the tensile strength was decreased by increasing the hole diameter. Comparing the results showed that the strength, failure mechanism and fracture patterns obtained numerically and experimentally were similar for both cases.