• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.278-278
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• 2022

Recently, the yield potential of high yield Tongil-type rice varieties has greatly increased, reaching 817kg/10a(Geumgang No.1). Moreover, in order to promote rice consumption and strengthen the competitiveness of the rice processing industry, the R&D of high yield Tongil-type rice varieties for each processing purpose, such as rice noodles, grain feed and industrial materials, has been continuously carried out. However, because Tongil-type rice varieties or lines are generally very vulnerable to cold damage, cold tolerance test can be said to be absolutely necessary to improve the cultivation safety. This study is the result of the seedling and field cold tolerance characteristic tests carried out in 2021 of high yield Tongil-type rice breeding lines. For the cold tolerance characteristic test of seedlings, total 303 high yield rice breeding lines for processing were treated in cold water of 13℃ and irrigation depth of 4cm for 10 days from the third-leaf age, then it was evaluated by comparing the degree of discoloration and withering with the checked varieties(Boramchan, Hanahreum No.2). Also, for the test of field, total 186 high yield rice breeding lines for processing were treated in cold water of 17℃ by keeping pouring day and night from 30 days after transplanting to ripening stage, then it was evaluated by comparing the degree of discoloration, delay of heading, shortening rate of stem length and percent of fertile grain etc. with the checked varieties. And the cold tolerance evaluative criteria were classified as strong(1~3), medium(4~6) and weak(7~9) in overall cold tolerance. (Seedling test) As for the degree of cold tolerance of the check variety, 'Boramchan' and 'Hanahreum No.2' showed a response of 'medium' and 'weak', respectively. However, there was no 'strong' line in the high yield rice breeding lines, 2 lines showed a 'medium' response, and 301 lines showed a 'weak' response. Therefore, except for a few lines(0.7%), most lines(99.3%) showed a 'weak' response. (Field test) In terms of the overall cold tolerance of the check variety, both 'Boramchan' and 'Hanahreum No.2' showed a 'medium' response. Similarly, there was no 'strong' line in the case of high yield rice breeding lines, 20 lines showed a 'medium' response, and 166 lines showed a 'weak' response. Therefore, except for some(10.8%) lines, most(89.2%) lines showed a 'weak' response. From the above results, we selected about 100 individuals with less seed shattering and degeneration of the ear tip, and with a relatively high percent of fertile grain, and are continuing to select lines with improved cold tolerance in the F4~F5 group in this year. As such, most of the Tongil-type rice varieties have poor cold tolerance and thus have low cultivation safety at low temperatures. However, it is important to select improved lines through generational progress because there are some lines that still have a certain level of cold tolerance among them.

• 한국대기환경학회지
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• 제23권6호
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• pp.744-751
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• 2007

Wet scrubber is widely used to remove toxic gaseous contaminants in various industries such as semi-conductor industry, display manufacturing industry and so on. In this study, to optimize a packed bed scrubber as one of typical wet scrubber size while keeping its performance, four different packing materials were investigated at different air flow rates, liquid-gas ratios and pH values. Ammonia, hydrochloric acid and hydrofluoric acid were used as test gases to characterize the scrubber performance. Gas removal efficiency increased as the packing size decreased, which resulted in the increase of specific surface area. The increase of air flow rate led to the decrease of gas removal efficiency, while the increase of liquid-gas ratio led to the increase of gas removal efficiency. For the case of $NH_3$ gas, lower pH, and for the cases of HCl and HF, higher pH contributed to higher gas removal efficiency. Gas removal efficiency of a wet scrubber increased in the order of HCl < $NH_3$ < HF according to its water solubility.

• International Journal of Naval Architecture and Ocean Engineering
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• 제4권4호
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• pp.488-503
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• 2012

The stern boat deployment system was investigated to evaluate the capability of launching and recovering rigid hull inflatable boat (RHIB) via the stern ramp. The main parameters to launch and recover RHIB were tested at the design stage. The combined hydrodynamic effect of the stern wake and the water jet flow made it difficult to maintain the maneuvering and sea-keeping ability of RHIB approaching to the stern ramp. The safe recovery course was proposed to maintain the directional control of RHIB and to reduce the combined hydrodynamic effect in the transom zone. To evaluate the feasibility of RHIB recovery, the stern sill depth was measured in various conditions and the ramp availability time was obtained. Also, the experimental percent time operability (PTO) test was performed by the number of successive launching and recovering operations.

• 한국수산과학회지
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• 제15권1호
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• pp.99-106
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• 1982

소형말쥐치를 보다 효율적으로 이용하고 지질을 개선하기 위한 방안으로서 새로운 형태의 조미건제품을 가공하고, 정질의 안전성을 저증시험에 의하여 평가하였다. (1) 두부, 숙장, 표피를 제거한 말쥐치를 fillet로 만든다. 이 fillet에 설탕, 식염, sorbitol, 생합성조미료 등을 배합한 분말조미료를 분포하여 조미한 다음 건조한다. 이것을 polyester/염화 viniliden/미연신 polypropylene ($12{\mu}m/15{\mu}m/50{\mu}m$) 적력film을 사용하여 진공포장한 다음, 조리와 살균을 겸하여 $80^{\circ}C$, 40분간 가열처리하여 제품으로 하였다. (2)이와 같이 조제한 조미건제품을 $35^{\circ}C$에서 약$3\sim4$개월간 저장하고, 그 간의 수분, 수분활성, 색조, torture, 생균수 등의 변화를 측정하였다. (3)제품은 저장중에 수분이 감소하고, 이에 따라 수분활성도 저하하고, 육조직의 경도도 증가하였다. (4)제품은 저장중에 질변하지만, 그 정도는 수분이 낮은 제품쪽이 수분이 많은 제품보다 심하였다. (5)고추가루를 사용한 제품이외는 세균은 검출되지 않았다. 고추가루를 사용한 제품에서는 세균이 검출되었지만 저장기간중 생균수는 증가하지 않았다. 따라서 이들 제품은 실온에서 $3\sim4$개월간 저장가능한 것이라고 판단하였다. (6) 관능검사결과로 보아 열품의 색조는 담황색인것 보다 약간 갈색을 핀 것이 좋았고, 육조직은 수분이 낮은 것 보다 높은 쪽이 유연하고 좋았다. 또한, 향미는 smoke flavor를 사용한 제품보다 beef flavor를 사용한 쪽이 더욱 좋았다.

• 한국수산과학회지
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• 제16권4호
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• pp.355-362
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• 1983

조미진주담치 건제품의 품질을 개선하기 위한 기초자료를 얻고자 진주담치를 원료로서 레토르트 파우치 조미진주담치건제품의 제조 및 저장중의 품질안정성에 대하여 검토하였다. 원료진주담치를 설탕 $1\%$, sorbitol $15\%$, glycerol $10\%$, 식염 $3\%$, monosodium glutamate $0.5\%$, 5-ribotide $0.5\%$ 및 물 $70\%$의 조미액에 $5^{\circ}C$에서 16시간 동안 침지시킨 다음 훈액처리($10\%$ Smoke EZ용액, 30초침지)한 후 가볍게 건조한다. 이것을 polyester/polyvinylidene chloride/말연신 polypropylene ($12{\mu}m/15{\mu}m/50{\mu}m$) 필름주머니를 사용하여 진공포장한 후 조리와 살균을 겸하여 열수순환식 레토르트에서 $120^{\circ}C$, 26분간 가열처리한 다음 급냉하여 레토르트 파우치 조미진주담치 건제품을 가공할 수 있었다. 이 제품은 $35^{\circ}C$에서 70일간 품질이 안정하게 유지되었으며, 특히 훈액처리조작은 제품의 색조와 향미를 개선하는 효과가 있었다.

• 한국치위생학회지
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• 제4권2호
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• pp.255-263
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• 2004

One of the best way to prevent dental caries and periodontal disease is removing dental plaque. Toothbrushing is also one of the crucial ways to gel rid of dental plaque and improve dental hygiene. The purpose of th is study was to examine how many bacteria were attached to toothbrushes used by dental palque acidogenecity and related behaviors to toothbrush use. Subjects in this study were 30 college students in their twenties, on whom a survey was conducted to find out how they cleansed their toothbrushes, how long they cleaned toothbrushes after brushing, and how to keep them. And then dental palque acidogenecity by caries activity test was implemented and the number of bacteria attached to their toothbrushes was tested. The findings of the study were as follows : 1. Concerning correlations between dental palque acidogenecity and the number of remaining bacteria in the toothbrushes used by students, the number of bacteria was lower in the group of students with no caries activity than in the group with mild caries activity. 2. As for relations between the way of cleansing toothbrushes and the number of bacteria, there was no statistically significant gap between the group of students who wetted their toothbrushes with water and rubbed the heads of them and the group of students who just only wetted their toothbrushes with no further actions. 3. Regarding the relationship of toothbrush cleansing time to the number of bacteria, the number of bacteria was lower in the group of students who cleansed their toothbrushes for 15 seconds or more. 4. As to the influence of the number of toothbrush used by students, there was no significant difference between the group using just one toothbrush and the other group using two or more toothbrushes. 5. As for correlations between the way of keeping toothbrushes and the number of bacteria, no significant gap existed between the group thai kept their toothbrushes separately and the other that didn't.

• 대한조선학회논문집
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• 제55권5호
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• pp.401-414
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• 2018

Planing hull type ships are often equipped with interceptor or trim tab to improve the excessive trim angle which leads to poor resistance and sea keeping performances. The purpose of this study is to design a controller to control the attitude of the ship by controllable stern interceptor and validate the effectiveness of the attitude control by the towing tank test. Embedded controller, servo motor and controllable stern interceptor system were equipped with planing hull type model ship. Prior to designing the control algorithm, a model test was performed to identify the system dynamic model of the planing hull type ship including the stern interceptor. The matrix components of model were optimized by Genetic Algorithm. Using the identified model, PID controller which is a classical controller and sliding mode controller which is a nonlinear robust controller were designed. Gain tuning of the controllers and running simulation was conducted before the towing tank test. Inserting the designed control algorithm into the embedded controller of the model ship, the effectiveness of the active control of the stern interceptor was validated by towing tank test. In still water test with small disturbance, the sliding mode controller showed better performance of canceling the disturbance and the steady-state control performance than the PID controller.

• 대한토목학회논문집
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• 제29권2A호
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• pp.171-179
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• 2009

콘크리트의 공극률은 유해인자의 주된 이동통로가 될 뿐 아니라, 수분을 보유할 수 있는 역할을 하게 되므로, 열화물질 이동 저항성을 평가할 수 있는 주된 지표가 되고 있다. 내구성에 대한 연구가 중요해짐에 따라, 공극구조를 기본으로 하는 열화모델이 최근 들어 개발되고 있으며, 공극구조와 내구특성간의 관계는 매우 중요하게 평가되고 있다. 본 연구는 5가지의 다른 물-시멘트비(40%, 45%, 50%, 55%, 60%)를 가진 시멘트 모르타르를 제조하여, 공극률을 포함한 다양한 내구성 실험을 수행하였다. 내구특성 실험은 기본적인 압축강도 실험을 포함하여, 투기성 실험, 염화물 확산계수 실험, 흡수율 및 수분 확산계수 실험 등이 수행되었다. 평가된 내구성 실험결과는 물-시멘트비와 공극률에 따라 분석되었다. 공극률이 1.45 배 높아질수록, 강도는 0.6배 수준으로 감소하였으며, 투기성, 염화물 확산계수, 흡수율, 수분확산계수는 각각 2.3배, 2.1배, 5.5배, 그리고 3.7배 수준으로 증가하였다. 이러한 내구특성 변화율은 높은 상관성을 보이며, 공극률에 따라 선형적으로 변화함을 알 수 있었다. 한편, 실험결과와 문헌분석을 통하여, 목표내구성능을 설정하였으며, 이에 따라서 고내구성 콘크리트를 위한 공극를을 제안하였다.

• 콘크리트학회지
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• 제7권2호
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• pp.155-164
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• 1995

본 연구는 증기양생을 실시하는공장제품을 대상으로 석고계 고강도콘크리트용 혼화재를 사용하여 콘크리트를 고강도화하는데 그 목적이 있다. 목표 슬럼프는 원심력 성형제품을 대상으로 슬럼프 $6{\pm}1cm$가 되도록 고성능감수제로 조절하였으며, 아울러 양생방법에 다른 고강도콘크리트용 혼화재를 사용한 콘크리트의 강도발현 특성을 검토하고자 증기 및 수중양생을 실시 비교하였다. 실험결로부터 고강도 콘크리트용 혼화재는 증기양생이 효과적이며 압축강도 발현은 단위결합재량 $530{\sim}600kg/m^3$의 조건에서 10%치환으로 무치환에 비하여 1.3배 증가된 $650kgf/cm^2$ 이상, 15-30% 치환시 1.4-1.5배 증가된 $700kgf/cm^2$이상을 얻었다. 따라서 고강도콘크리트용 혼화재는 증기양생시의 고강도콘크리트 제조에 효과적으로, 시멘트2차제품 제조에 오오토클레브 양생을 하지 않고 증기양생만으로 고강도콘크리트를 얻을 수 있는 유효한 혼화재임을 나타냈다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.1033-1036
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• 2002

Wafer bonding methods such as fusion and anodic bonding suffer from high temperature treatment, long processing time, and possible damage to the micro-scale sensor or actuators. In the localized bonding process, beating was conducted locally while the whole wafer is maintained at a relatively low temperature. But previous research of localized heating has some problems, such as non-uniform soldering due to non-uniform heating and micro crack formation on the glass capsule by thermal stress effect. To address this non-uniformity problem, a new heater configuration is being proposed. By keeping several points on the heater strip at calculated and constant potential, more uniform heating, hence more reliable wafer bonding could be achieved. The proposed scheme has been successfully demonstrated, and the result shows that it will be very useful in hermetic packaging. Less than 0.2 ㎫ contact Pressure were used for bonding with 150 ㎃ current input for 50${\mu}{\textrm}{m}$ width, 2${\mu}{\textrm}{m}$ height and 8mm $\times$ 8mm, 5mm$\times$5mm, 3mm $\times$ 3mm sized phosphorus-doped poly-silicon micro heater. The temperature can be raised at the bonding region to 80$0^{\circ}C$, and it was enough to achieve a strong and reliable bonding in 3minutes. The IR camera test results show improved uniformity in heat distribution compared with conventional micro heaters. For gross leak check, IPA (Isopropanol Alcohol) was used. Since IPA has better wetability than water, it can easily penetrate small openings, and is more suitable for gross leak check. The pass ratio of bonded dies was 70%, for conventional localized heating, and 85% for newly developed FP scheme. The bonding strength was more than 30㎫ for FP scheme packaging, which shows that FP scheme can be a good candidate for micro scale hermetic packaging.