• 대한화학회지
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• 제10권3호
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• pp.123-128
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• 1966

The preparation of bismuthsubnitrate for the purpose of medicine, with both crude and refined bismuth metals, has been performed by applying the following methods: (A) Neutralization process, (B) Hydrolysis process. On the basis of results of a series of experiments, the following conclusion was obtained: 1) The quantitative determination showed that there was little difference between these two processes, in their yields. However the process (B), hydrolysis method was technically more simple than (A), neutralization method, and purity of final product by process (B) was found to be much more superior to (A). 2) It was found that bismuthsubnitrate products obtained from refined bismuth metal was almost the same with imported ones (Fisher, Squibb, etc.) in their purities.

• 접착 및 계면
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• 제23권4호
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• pp.101-107
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• 2022

Adhesive joints have many advantages such as weight savings, corrosion and fatigue resistance and now developed even withstand of high impact and dynamic loads. However, an adhesion has cumbersome and complicated surface preparation processes. The surface preparation step is critical in adhesive joint manufacturing in order to obtain the prescribed strength for adhesive joints. In this study, it was attempted to simplify and reduce the number of surface preparation steps, and abrasion and rapid adhesive application (ARAA) process is developed for an alternative solution. The abrasion processes are performed only for creating surface roughness in standard procedures (SP), although the abrasion processes cause surface activation itself. The results showed that there is no need the long procedures in laboratory or chemical agents for adhesion. After the abrasion process, the attracted and highly reactive fresh surface layer obtained, and its effect on bonding success is observed and analyzed in this research, in light of the essential physic and adhesion theories. Al 6061 aluminum adherends and epoxy-based adhesives were chosen for bonding processes, which is mostly used in light vehicle parts. The adherends were cleaned, treated and activated only with abrasion, and after the adhesive application the specimens were tested under quasi-static loading. The satisfied ARAA results were compared with that of the specimens fabricated by the standard procedure (SP) of adhesion processes of high impact loads.

• 실천공학교육논문지
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• 제13권2호
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• pp.405-419
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• 2021

본 연구는 공학계열 대학생을 대상으로 학습민첩성과 취업준비행동의 관계에서 학습몰입과 교수-학생 간 상호작용의 조절된 조절효과를 확인하는 것을 목적으로 한다. 이를 위해 2년제 P대학 2학년 재학생 206명으로부터 수집한 데이터를 바탕으로 Process v3.5.3 for SPSS를 활용하여 연구 모델의 조건부 효과(직접효과 및 조절된 조절효과) 분석을 실시하였다. 연구결과 첫째, 공학계열 대학생의 학습민첩성은 취업준비행동에 유의한 정적 영향을 미치는 것으로 나타났다. 둘째, 학습민첩성과 취업준비행동의 관계에서 학습몰입은 유의한 부적 조절효과가 존재하는 것으로 나타났다. 셋째, 학습민첩성과 취업준비행동 관계에서 학습몰입의 조절효과는 교수-학생 간 상호작용 빈도에 의해 조절되고, 그 영향은 통계적으로 유의하고 정적인 것으로 나타났다. 연구결과를 바탕으로 학문적·실무적 논의와 시사점을 제시하였다.

• 융합정보논문지
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• 제11권6호
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• pp.162-170
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• 2021

본 연구는 그릿과 진로준비행동의 관계에서 진로정체감과 진로결정자기효능감의 이중 매개효과를 중심으로 인과관계를 파악하고자 하였다. B 지역 내 치위생(학)과 학생을 대상으로 구조화된 설문지를 이용한 자기기입식 설문조사를 통해 자료를 수집하였고, SPSS와 Process Macro을 사용하여 분석하였다. 진로준비행동에 직접적인 영향을 미치는 가장 큰 요인은 진로정체감이었고, 그릿, 진로결정자기효능감 순이었다. 경로분석을 통해 그릿은 진로정체감을 매개로, 그릿은 진로정체감과 진로결정자기효능감을 매개로 진로준비행동에 간접적으로 유의한 영향을 미쳤다. 이는 적극적인 진로준비행동을 위하여 그릿과 진로정체감을 높여야 함을 시사하므로, 치위생 전공 대학생의 진로 교육 컨텐츠 개발의 기초 자료로 활용하고자 한다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2013년도 춘계학술대회 논문집
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• pp.473-474
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• 2013

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2003년도 추계총회 및 연구발표회 초록집
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• pp.53.1-53
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• 2003

• 산경연구논집
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• 제11권7호
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• pp.19-28
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• 2020

Purpose: In this study, we would like to confirm that the transfer of young workers may be a means of enhancing their internal satisfaction, not to get a better job, by setting work-related characteristics that are highly relevant to job-related factors. Research design, data, and methodology: In this study, preparation for turnover was set as dependent variables to identify factors related to the turnover of young people, and the type of business, employment type, debt status, job satisfaction, job difficulty compared to education level, job difficulty, job degree, job major agreement, debt status, and other demographic social characteristics were selected as independent variables. Results: The characteristics related to personal criteria in job-seeking process were significant in the form of business, employment type, job satisfaction, work difficulty compared to the level of education, work difficulty compared to the level of technology, job major matching, and debt status. Conclusions: This study confirmed that young people's turnover may not simply be a means to get a better job, but to increase satisfaction in the internal aspects of their jobs, and that for young people, a job is an important development process that represents their identity and needs to be approached from a life-cycle perspective.

• 한국입자에어로졸학회지
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• 제6권1호
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• pp.21-27
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• 2010

New process consisting of electrospray and epitaxial crystal growth processes was applied to the preparation of c-plane oriented barium ferrite ($BaFe_{12}O_{19}$) thin film for high density magnetic recording media. Sodium citrate aided process was proper to preparation of amorphous $BaFe_{12}O_{19}$ nanoparticles with geometric mean diameter of 3 nm and geometric standard deviation of 1.1. The electrospray was applicable to the prepare of amorphous $BaFe_{12}O_{19}$ thin film on a substrate, and the film thickness could be controlled by adjusting the electrospray deposition time. The c-plane oriented $BaFe_{12}O_{19}$ thin film was successfully prepared by 3 step annealing process of the $BaFe_{12}O_{19}$ amorphous film on a sapphire($Al_2O_3$) substrate; annealing at $350^{\circ}C$ for 30 min, annealing at $500^{\circ}C$ for 30 min, and annealing at $700^{\circ}C$ for 60 min.

• Membrane and Water Treatment
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• 제13권4호
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• pp.191-199
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• 2022

In industrial production, the development of traditional polyamide nanofiltration (NF) membrane was limited due to its poor oxidation resistance, complex preparation process and high cost. In this study, a composite NF membrane with high flux, high separation performance, high oxidation resistance and simple process preparation was prepared by the method of dilute solution dip coating. And the sulfonated polysulfone was used for dip coating. The results indicated that the concentration of glycerin, the pore size of the based membrane, the composition of the coating solution, and the post-treatment process had important effects on the structure and performance of the composite NF membrane. The composite NF membrane prepared without glycerol protecting based membrane had a low flux, when the concentration of glycerin increased from 5% to 15%, the pure water flux of the composite NF membrane increased from 46.4 LMH to 108.2 LMH, and the salt rejection rate did not change much. By optimizing the coating system, the rejection rate of Na₂SO₄ and PEG1000 was higher than 90%, the pure water flux was higher than 40 LMH (60psi), and it can withstand 20,000 ppm.h NaClO solution cleaning. When the post treatment processes was adjusted, the salt rejection rate of NaCl solution (250 ppm) reached 45.5%, and the flux reached 62.2 LMH.

• 산업진흥연구
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• 제8권3호
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• pp.69-78
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• 2023

본 연구는 늘어난 노년기를 대비하여 다양한 영역의 통합적인 노후 준비가 필요하다는 인식을 바탕으로 중장년층의 노후 준비 실태와 특성을 파악하고 성공적 노화와의 관계를 밝히는 데 그 목적이 있다. 또한, 중장년층을 대상으로 노후 준비와 성공적 노화 간의 관계에서 사회적 지지의 매개효과를 알아보고자 함이다. 이를 확인하기 위해 국민연금연구원에서 시행하고 있는 국민 노후 보장패널(Korean Retirement & Income Study: KReIS)의 제3차 조사, 제4차 조사 그리고 제5차 부가 조사에 모두 응답한 50세 이상 64세 미만의 남녀 1,037명을 분석하였다. 중고령자의 노후 준비가 성공적 노화에 영향을 미칠 때, 사회적 지지의 매개효과를 검증하기 위하여 IBM SPSS 26 Process Macro Model 4와 부트스트래핑(Bootstrapping)을 실시하였다. 독립변수가 매개변수에 미치는 유의성 검증 결과, 노후 준비는 정(+)적으로 유의하게 나타났다. 즉, 노후 준비가 높을수록 사회적 지지가 높아지는 것으로 검증되었다. 또한, 독립변수인 노후 준비와 매개변수인 사회적 지지가 종속변수인 성공적 노화에 미치는 영향의 유의성을 검증한 결과, 독립변수인 노후 준비는 성공적 노화에 유의한 영향을 미치는 것으로 나타났고, 매개변수인 사회적 지지도 성공적 노화에 유의한 영향을 미치는 것으로 나타났다. 본 연구 결과는 중장년층의 노후 준비를 통해 성공적 노화를 위한 사회적 지지의 필요성을 시사한다. 노후 준비를 위한 정책적인 시사점을 도출하여 성공적 노화 수준을 높이기 위한 기초자료로 제공하고자 한다.