• 한국수학교육학회지시리즈A:수학교육
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• 제48권3호
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• pp.287-302
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• 2009

This study investigated how 5th grade students found and understood triangle congruence conditions (SSS, SAS, ASA). In particular, this study focused on children's processes of discovering triangle congruence conditions and the obstacles which they encountered in the process of making sense of these conditions. Our data indicates that inquiring the cases in which less than three factors of triangle are given is helpful for children to guess triangle congruence conditions and understand the minimal characteristic of these conditions. And the degree of difficulty of discovering each congruence condition is different. Children discovered SAS condition and ASA condition easily, but it was hard for them to discover and understand that SSS was also a triangle congruence condition because they connected the length of a given side with the use of a scaled ruler not a compass.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 학술회의 논문집 정보 및 제어부문 B
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• pp.608-611
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• 2003

A large part of the embedded system, compared with the PC, have low performance CPU and small memory. So the embedded operating system fits the condition of that hardware system. A Single Address Space (SAS) OS has the operating system and all applications in the single address space. The SAS architecture enhances sharing and co-operation, because addresses have a unique interpretation. Thus, pointer-based date structures can be directly communicated and shared between programs at any time, and can be stored directly on storage. The key point of the SAS OS on the embedded system is the low overhead inter-action between programs in process and usage. So SAS OS can be ported on the low performance CPU. In this paper, we design the SAS OS (named emNOS, Embedded Network Operating System) on the ARMTTDMI processor. Finally we show the benefits of the SAS OS on the embedded system.

• 한국항공운항학회:학술대회논문집
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• 한국항공운항학회 2004년도 추계학술발표대회 논문집
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• pp.279-284
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• 2004

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2017년도 춘계 종합학술대회 논문집
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• pp.103-104
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• 2017

목표: 제조업은 산업 재해가 가장 많이 발생하며, 산업 재해를 예방하기 위해 산업계 근로자가 알고 있는 안전 환경을 연구하는 것이 중요합니다. 방법: 2015년 PSWCI 패널 보고서에 응답한 근로자 중 연구 대상은 남성 1,123명이었다. 연구 대상은 영향을 받는 주관적인 건강을 겪은 후 1년 동안의 고용 상태의 변화에 따라 피험자를 분류하여 분석을 했다. 통계 분석은 SAS 버전 9.4 (SAS Institute Inc., Cary, NC, USA)를 사용하여 수행되었습니다. 결과: 분석 결과에 따르면 제조 산업은 근로자 조건에 따라 경제적 활동과 건강상태에 차이가 있었습니다. 제조업 환경의 역동적인 변화의 측면은 성별과 일시적인 상태와 실업 상태 사이에서 남성이 더 높은 경향을 보였다. 결론: 이 연구의 결과는 제조 업계 종업원들이 느끼는 작업 환경의 안전 수준을 향상시키기 위한 것이다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.802-805
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• 2003

Structural surface becomes an antenna. The integration of antennas into structural body panels is a new high payoff technology. It emerged from the need to improve structural efficiency and antenna performance. In this paper, we developed new design concept for the structural surface which transmits and receives the electromagnetic signals, and it is termed Surface-Antenna-Structure (SAS). Design procedure was presented including structure design. material selection and design of antenna elements, which was processed according to the communication with KORSAT satellite at Ku-Band (12.25-12.75 GHz). The final demonstration article was 350$\times$200$\times$7.5mm flat antenna panel. Experimental results for antenna performances were in good agreements with design requirements. Also structural analysis was performed with SAS. estimating stress distributions under simply supported condition with Laminated Plate Theories and Wavier Solutions. The SAS concept can be extended to give a useful guide to manufacturers of structural body panels as well as antenna designers. promising innovative future communication technology.

• 한국군사과학기술학회지
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• 제25권4호
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• pp.329-338
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• 2022

This paper provides a case study of development testing and evaluation of design goal of Interferometric SAS (Synthetic Aperture Sonar) system that is developing supported by Civil-Military Technology Cooperation Center in offshore fields. For Deep water operating capabilities evaluation, We have surveyed candidate field, bathymetric mapping and target identification over 200 m depth, East Sea. In testing phase, We have provided environmental information of testing field include water column, seabed and weather condition in real time. And to compare excellency of developing InSAS, we have gather commercial imaging sonar system data with same target. This case study will support the Test Readiness Review of future underwater surveillance system developing via investigate marine testing field environment, testing facilities and planning.

• Korean Chemical Engineering Research
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• 제55권2호
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• pp.225-229
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• 2017

최근 약물전달시스템으로 널리 주목받고 있는 dextran의 미립자는 초임계 반용매 공정을 통해 얻을 수 있다. 초임계 반용매(SAS) 공정에서는 DMSO (dimethyl sulfoxide)에 용해되어 있는 dextran이 반용매인 초임계 $CO_2$의 첨가에 의한 재결정으로 얻어진다. 본 연구에서는 이 공정의 적절한 운전조건을 제시하기 위하여 가변부피 셀을 이용하여 cloud point를 측정함으로써 Dexran/DMSO/$CO_2$의 상거동을 관찰하였다 실험결과로부터 dextran 미립자 제조를 위한 초임계 반용매 공정의 적절한 온도(300.15 K~330.15 K), 압력(90 bar~130 bar), 용질의 농도(5 mg/ml~20 mg/ml)의 범위를 결정하였다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2002년도 생물공학의 동향 (X)
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• pp.131-135
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• 2002

Acetobacter xylinum KJ1 efficiently producing bacterial cellulose(BC) in shaking culture was isolated from a rotten grape. The strain was used to investigate optimum operating conditions for increasing BC production and factorial design model was employed for the optimization. The results of experiments were statistically analyzed by SAS program. Reciprocal effects of each factors(carbon source concentration, shaking speeds(rpm), oxygen pressure, and CSL concentration) and culture condition of BC production were examined by getting regression equation of the dependent variable. Comparisons between experimental results and predicted results about BC concentration were done in total 24 experiments by combination of each factors using SAS program, and the correlation coefficients of BC concentration and BC yield were 0.91 and 0.81, respectively. The agitated cultures were performed in various operation conditions of factors which affected considerably to BC production in jar fermentor. The results showed that BC concentration was 11.67g/ L in 80 hours cultivation under the condition of carbon source concentration shaking speeds(rpm) : oxygen pressure: CSL concentration = 4% : 460rpm : 0.28 : 6%. On the other hand BC yield was 0.42g/g in 80 hours cultivation under the condition of carbon source concentration shaking speeds(rpm) : oxygen pressure: CSL concentration = 4% : 564rpm : 0.21 : 2%. The BC production could be enhanced up to more than 65.3% by factorial design. The result of a verifying experiment under the optimal conditions determined by the factorial design to the BC production showed that the model was appropriate by obtaining BC concentration of 11.02g/L in the optimum condition

• 한국환경농학회지
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• 제20권5호
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• pp.352-357
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• 2001

Cadmium (Cd) has been identified as a potential contaminant in agricultural and environmental soils. Ionic condition in the soils is an important factor to influence Cd availability. In this study, the effect of sulfate or nitrate application on Cd sorption in acidic and calcareous soils was investigated. The Cd, sulfate $(SO_4)$, and nitrate $(NO_3)$ sources were solutions of $CdCl_2$, $K_2SO_4$, and $KNO_3$, respectively. The soil-solution system pH was affected by the application of sulfate or nitrate in both acidic and calcareous soil system, but there was not clear pH difference between pre- and simultaneous applications of sulfate or nitrate (PAS/PAN or SAS/SAN). Solution ionic strength (I) values were similar between the acid and calcareous soil systems after applying the Cd even though it was significantly different in the untreated control soils. However after applying the sulfate or nitrate, the I values increased and were always higher with SAS/SAN treatments. Solution Cd concentration also increased with the application of sulfate or nitrate. However, the Cd concentration in soil solution controlled by Cd sorption in the systems was different between PAS/PAN and SAS/SAN treatments only in the calcareous soil system, but not in the acidic soil system. The difference in Cd concentration between SAS/SAN and PAS/PAN in the calcareous systems may be caused by system pH, ionic strength, complexation, and predominately, competition of the $Cd^{2-}$ with the index $K^+$ ion. Potassium ion-Cd competition in the acidic soil system may be minimized because of the abundance of hydrogen ions.

• KSBB Journal
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• 제17권3호
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• pp.228-234
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• 2002

Factorial design model을 이용하여 A. xylinum KJ1의 BC생산을 위한 최적 배양조건을 결정하였다. 요인 분석을 위한 실험 계획법으로는 부분요인 분석을 통한 factorial model을 이용하였으며, 주요 실험인자인 탄소원 농도, 교반속도(rpm), 산소분압, CSL의 농도의 네 가지 factor의 영향에 의한 BC생산량의 변화를 측정하였다. SAS 프로그램을 이용하여 전체 24개의 실험계획에서 각각의 factor의 조합에 의한 BC 생산성에 관한 결과 및 예측값을 비교한 결과 BC 생산량 면에서는 상관계수($R^2$)가 0.91으로 이었고, 수율면에서는 상관계수($R^2$)는 0.81이다. 최적 BC 생산을 위한 각 factor들이 탄소원의 농도 4%, 교반속도 460 rpm, 산소분압 0.28 atm, CSL 농도 6%일 때, 이때의 BC 생산량은 11.67 g/L로 예측되었다. 그리고 BC 생산 수율면에서 최적 배양조건이 탄소원 농도 4%, 교반속도 564 rpm, 산소분압 0.21 atm, CSL 농도 2%일 때 최적의 수율 0.42 g/g를 얻을 수 있을 것으로 예측되었다. 결정된 최적 조건에서의 실증 실험 결과 11.47 g/L의 BC 생산량을 얻을 수 있었으며, 이는 fermentor상에서의 기본실험에서 얻은 4.83 g/L보다 2.4배 이상 향상된 결과이다.