• 대한간호
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• 제13권4호통권72호
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• pp.40-46
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• 1974

• Current Research on Agriculture and Life Sciences
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• 제25권
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• pp.19-23
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• 2007

This research to streets at Daegu, and view adjective how people react when draw a bird into interior in city utilize and examine becoming direction of street trees system. Findings on survey, citizens appear by average 2.87 in management degree of street trees and average 2.76 in various of species of trees, discontent thing more or less by average 2.91 in satisfaction of the beauty, and demonstrate high shame from satisfaction for season stuff to comparative high 3.24, generally, citizens appear by there are parts to improve by do dissatisfaction about street trees system at Daegu. Also, street trees 2 lines plantings for a bird is average 3.05, shows affirmative feedback about that shrub utilization for a bird see high numerical value by average 3.4 and people draw a bird to space of city. Therefore, construct street trees friendly to the nature and be considered to need to re-establish set street trees environment in citizens preference to recover city ecosystem. As result that examine reaction which treat in street trees planting programs to draw birds into city through view adjective, Likert scales about 2 lines plantings of street trees and additional planting of shrub show affirmative feedback by average 3.4 both ordinary people and specialist group, if people want to draw birds into city by various of method, various research should be accomplished.

• KSBB Journal
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• 제24권1호
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• pp.70-74
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• 2009

본 연구에서는 음식물쓰레기를 당화시키기 위해 섬유소분해효소를 효율적으로 배양하고자 먼저 refill하는 멘델배지의 농도를 0.5%로, 새로운 배지의 주입시간을 12시간으로 결정하였다. Flask 레벨에서는 fill-and-draw 방법으로 12시간 단위로 연속배양한 결과, amylase 활성은 300시간까지 1.0 U/mL 내외로 유지되었으며, FPase 활성은 156시간까지 0.40 U/mL 이상으로 유지되었다. 이때의 효소생산성은 amylase 3.49 U/L. hr, FPase 1.02 U/L. hr 이었다. 10 L에서는 batch, fed-batch, fill-and-draw 방법으로 효소를 생산한 결과 batch에서 가장 높은 효소생산성을 나타내었으며, 그다음은 fed-batch 이었다. Batch에서의 효소생산성은 amylase 42.30 U/L. hr, FPase 5.60 U/L. hr, fed-batch에서는 각각 23.03, 2.76 U/L. hr 이었다. 그리하여 T. inhamatum KSJ1을 이용한 섬유소분해효소의 연속배앙에서 10 L 생물반응기에서 fed-batch 빙법이 가장 효율적이었다.

• 상하수도학회지
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• 제32권4호
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• pp.357-361
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• 2018

Forward osmosis (FO) process has been attracting attention for its potential applications such as industrial wastewater treatment, wastewater reclamation and seawater desalination. Particularly, in terms of fouling reversibility and operating energy consumption, the FO process is assumed to be preferable to the reverse osmosis (RO) process. Despite these advantages, there is a difficulty in the empirical step due to the lack of separation and recovery techniques of the draw solution. Therefore, rather than using FO alone, recent developments of the FO process have adapted a hybrid system without draw solution separation/recovery systems, such as the FO-RO osmotic dilution system. In this study, we investigated the performance of the hollow fiber FO module according to various operating conditions. The change of permeate flow rate according to the flow rates of the draw and feed solutions in the process operation is a factor that increases the permeate flow rate, one of the performance factors in the positive osmosis process. Our results reveal that flow rates of draw and feed solutions affect the membrane performance, such as the water flux and the reverse solute flux. Moreover, use of hydraulic pressure on the feed side was shown to yield slightly higher flux than the case without applied pressure. Thus, optimizing the operating conditions is important in the hollow fiber FO system.

• 대한전자공학회논문지SP
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• 제38권4호
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• pp.434-441
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• 2001

본 논문에서는 공간 히스토그램과 웨이브렛 모멘트를 융합하여 검색 효율을 크게 향상시키는 방법을 제안한다. 이 방법에서는 질의영상과 DB영상간의 유사도를 구할 때 히스토그램의 유사도와 웨이브렛 모멘트의 유사도를 효과적으로 융합한다. 즉, 공간적 이동, 회전 등에 강한 히스토그램 특징과 주파수 대역별로 구해지는 웨이브렛 모멘트 특징을 잘 융합함으로써 검색성능의 향상을 추구한다. 제안한 방법의 성능을 평가하기 위한 시험영상 DB로는 Brodatz 질간 영상 DB와 Corel Draw Photo 영상 DB를 사용하였다. 실험 결과, 제안한 방법으로 구한 검색율이 Brodatz DB에서 히스토그램이나 웨이브렛 모멘트만으로 구한 검색율보다 각각 5.3%와 13.8% 향상되었고, Corel Draw Photo DB에서는 각각 15.5%와 3.2% 향상됨을 확인할 수 있었다.

• Membrane and Water Treatment
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• 제8권5호
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• pp.449-462
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• 2017

Direct treatment of municipal wastewater by forward osmosis (FO) process was evaluated in terms of water flux decline, reverse salt diffusion, pollutants rejection and concentration efficiency by using synthetic seawater as the draw solution. It was found that when operating in PRO mode (active layer facing the draw solution), although the FO membrane exhibited higher osmotic water flux, more severe flux decline and reverse salt diffusion was also observed due to the more severe fouling of pollutants in the membrane support layer and accompanied fouling enhanced concentration polarization. In addition, although the water flux decline was shown to be lower for the FO mode (active layer facing the feed solution), irreversible membrane fouling was identified in both PRO and FO modes as the water flux cannot be restored to the initial value by physical flushing, highlighting the necessity of chemical cleaning in long-term operation. During the 7 cycles of filtration conducted in the experiments, the FO membrane exhibited considerably high rejection for TOC, COD, TP and $NH_4{^+}-N$ present in the wastewater. By optimizing the volume ratio of seawater draw solution/wastewater feed solution, a concentration factor of 3.1 and 3.7 was obtained for the FO and PRO modes, respectively. The results demonstrated the validity of the FO process for direct treatment of municipal wastewater by using seawater as the draw solution, while facilitating the subsequent utilization of concentrated wastewater for bioenergy production, which may have special implications for the coastline areas.

• 폴리머
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• 제24권6호
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• pp.820-828
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• 2000

본 연구에서는 블렌드 내의 분산상을 잘 발달된 판상 구조로 발현시켜 폴리프로필렌 (PP)/에틸렌 비닐알코올 공중합체 (EVOH) 블렌드의 차단 성질을 향상시키기 위하여 필름 제조 공정으로써 이축연신 공정을 사용하였다. 분산상 수지와 연속상 수지의 점도비로부터 용융 압출 공정시 변형의 정도를 파악하기 위하여 각 수지의 유변물성을 측정하였으며, 상용화제 함량과 연신 배율 및 연신 온도 등이 이축연신 블렌드 필름의 산소 투과도와 모폴로지에 미치는 영향을 조사하였다. l5 wt%의 EVOH를 첨가한 PP/EVOH 블렌드 필름의 산소차단성은 EVOH 분산상이 이축연신에 의해 넓은 면적의 판상구조로 발현되어 순수 PP에 비해 10배 정도까지 증가한 것으로 나타났다. 모폴로지를 조절하친 두 상간의 계면결합력을 증진시키기 위하여 PP-g-MAH와 ionomer를 사용한 결과, 차단 효과를 효과적으로 향상시키기 위해서는 상용화제를 블렌드에 최적의 함량으로 첨가해야 한다는 사실을 알 수 있었다. 또한 높은 연신 배율과 연신 온도로 이축연신하여 제조된 블렌드 필름에서 더욱 뚜렷한 판상 모폴로지가 관찰되었으며, 차단효과는 증가한 것으로 나타났다.

• 한국지구과학회지
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• 제35권5호
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• pp.375-384
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• 2014

The number of students choosing science, technology, engineering, and mathematics (STEM) related careers are declining. Thus it became a worldwide challenge in the $21^{st}$ century. As public images of the engineers are unfavorable and inaccurate, misconceptions and stereotypes about engineers are prevailing. The purpose of this study was to investigate elementary school students' perceived mental and pictorial images of engineers and the nature of engineering work. This study involved 512 fifth and sixth grade students (Boys: 287 and Girls: 225) from four elementary schools at one of metropolitans in South Korea. The Draw An Engineer-Korean version (DAE-K) was developed based on Draw an Engineer (DAE) and Draw a Scientist (DAS), and Song and Kim (1999)'s instruments. A pilot-tested was conducted with 33 elementary students prior to the main study. The students were asked to answer how they think the engineers would be, to draw an engineer at work, and to write the engineer's personal information and the job description. Engineers were perceived as a person fixing, building, manufacturing, working outdoors in labors' clothes such as a robe. Engineers were shown with building tools, robots, airplanes, machines, conveyor belt, etc. Moreover, compared to the scientists, engineers were perceived as less intelligent, less imaginative, and less accurate. The results of this study revealed that elementary school students had a lack of accurate images of engineers. Students' current perceived images of engineers could help educators find the baselines for the future engineering education in elementary schools. In addition, the findings of this study could also contribute to the development of engineering education in terms of gender issues, STEM career choice, and even cultural diversity.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제10권2호
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• pp.186-194
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• 1999

목 적：본 연구에서는 인물화 검사가 아동들의 구체적/추상적 사고를 평가하는 비언어적 도구로서 유용하게 사용될 수 있는지를 살펴보았다. 방 법：임상 집단으로 서울대학 병원 소아 정신과를 방문한 아동 30명과 정상 아동 27명을 대상으로 KEDI-WISC와 인물화 검사를 실시하고 추상적 사고 능력을 평가하는 언어적 검사로써 공통성 소검사 점수와 인물화 점수들을 비교하였다 결 과：정상 아동 집단에는 유의미한 상관을 보이지 않았으나, 임상 집단에서 공통성 소검사 점수와 인물화 점수간에 높은 상관을 보였으며, 특히 이들의 인물화 추상 점수와 공통성 소검사간에 매우 높은 상관을 나타낸 것을 볼 때, 인물화 검사 결과가 임상 집단에서 추상적 사고 특성들을 보다 잘 평가하는데 사용될 수 있음을 시사하였다.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2007년도 춘계학술대회 논문집
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• pp.310-313
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• 2007

This paper covers finite element simulations to evaluate the bending limit of double pipe for tube-hydroforming. The tube-hydroforming process starts with a straight precut tube. The tube is often prebent in a rotary draw bending machine to fit the hydroforming tool. During the bending the tube undergoes significant deformation. So forming defects such as wrinkling, thinning and flattening are generated in the tube. Consequently we analyzed the effect of process parameters in rotary draw bending process and searched the optimized combination of process parameters to minimize the forming defects using orthogonal arrays. The characteristic to evaluate the effects of the process parameters is the bending angle which wrinkling is generated, we define the bending angle at that time as bending limit. Of many process parameters, the process parameters of the bending process such as gab between inner and outer tube, boosting force, dimensions of mandrel were analyzed. And we observed the deformation modes of bent double pipe at specific bending angle in each parameter combination.