• 센서학회지
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• 제10권4호
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• pp.250-258
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• 2001

본 연구에서는 지상에서 전장의 세기를 측정하는 것에 의해 낙뢰 예측이 가능한 뇌경보시스템을 개발하였다. 뇌경보시스템은 전장센서로써 회전형 필드밀, 임피던스변환기, 2단 증폭기 및 마이크로프로세서로 구성되어 있다. 교정 실험결과로부터 뇌경보시스템의 주파수대역과 최대 분해능은 각각 $DC{\sim}200\;[Hz]$, 73[V/m]이었으며, 뇌운에 의한 대지전장의 세기를 18.7 [kV/m]까지 측정할 수 있음을 확인하였다. 실제 상황에서 본 뇌경보시스템의 감지능력을 평가하기 위하여 뇌운의 모델을 이용한 컴퓨터 시뮬레이션을 수행하였으며. 그 결과 관측점으로부터 6 [km] 이내에 접근하는 뇌운의 움직임을 관측할 수 있었다.

• 한국산업보건학회지
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• 제10권1호
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• pp.147-159
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• 2000

The NIOSH health hazard evaluation program (HHE program) was created in response to the mandate to determine the toxic effect and potential health hazard of workplace exposure, which is found in Occupational Safety and Health Act of 1970 and the Federal Mine Safety and Health Act of 1977, A primary benefit of HHE program is its ability to provide current health hazard data to employers and employees, which assists them in identifying solutions to occupational health and safety problems in their workplaces, The HHE program also stimulates research in the development and review of sampling methods and diagnostic tests and may prompt additional exposure assesment efforts and toxicological and epidemiological studies. HHE projects also provide human exposure-toxicity data that are used to asses the validity of existing occupational health standards and to support criteria for new standards of recommendation, The HHE request is classified into four categories: 1) category 1: As a administratively invalid, 2) category 2: These are valid requests for which a site visit is not essential to an appropriate response, 3) Category 3 : These are valid requests for which a site visit is necessary for an adequate evaluation, 4) These are valid request which present a complex problem or an opportunity for research, To carry out HHE program one or methods of investigation might be used: 1) direct observation and evaluation of production processes and employee work practices 2) employees exposure level and air contamination level 3) medical test or physical examinations of employees 4) private, confidential interviews with employees 5) review of employer's record of injuries and illness, employee exposure data, medical tests and job histories. After investigation and analysing the data, NIOSH issues a final report, giving finding and recommendation.

• 식물병연구
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• 제18권4호
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• pp.268-276
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• 2012

Broad bean wilt virus 2 (BBWV2), genus Fabavirus, subfamily Comovirinae, family Secoviridae, causes damage in many economically important horticultural and ornamental crops. Sequence alignments showed several conserved sequences in 5' non-coding regions (5' NCRs) of RNA 1 and RNA 2 in all BBWV2 strains characterized so far. Based on this observation, we generated a hpRNA construct (pIR-BBWV2) harboring an inverted repeat containing a 210 bp cDNA fragment homologous to 5' NCR portion of BBWV2 RNA 1 to investigate the silencing potential for its ability to interfere with a rapidly replicating BBWV2. Agrobacterium-mediated transient expression of the IR-BBWV2 had a detrimental effect on BBWV2 infection, showing no distinct symptoms in non-inoculated leaves of the agroinfiltrated Nicotiana benthamiana plants. BBWV2 genomic RNAs were not detected by RT-PCR from tissues of both the inoculated leaves and upper leaves of the agroinfiltrated plants. Accumulation of virus-derived small interfering RNAs was detected in the inoculated leaf tissues of N. benthamiana plants elicited by transient expression of IR-BBWV2 indicating that RNA silencing is responsible for the resistance to BBWV2.

• 정보교육학회논문지
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• 제12권3호
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• pp.323-332
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• 2008

본 연구에서는 초등학생의 프로그래밍 학습을 효과적으로 조력하기 위해 새로운 교육용 프로그래밍 언어인 스크래치를 활용한 프로그래밍 학습의 가능성을 제시하고자 하였다. 스크래치 프로그래밍 학습 내용은 프로그래밍 과정에서의 학습자의 내적 동기 유발을 위한 전략과 복잡한 인지 능력 향상을 위한 창의적 문제해결 수업모형(CPS)을 토대로 구성하였다. 설계된 학습 내용을 초등학교 6학년 재량활동 시간에 적용한 결과, 스크래치 프로그래밍 학습은 학습자의 내재적 동기와 문제해결력 향상에 효과가 있는 것으로 나타났다. 최근 정보통신기술교육 운영지침의 개정으로 프로그래밍 교육과 알고리즘 교육이 초등학교에서도 필요하게 되었고 학교 현장의 여건 등을 고려해보면 본 연구를 통해 설계된 교수 학습 전략을 기반으로 한 스크래치 프로그래밍 학습은 의미 있는 선택이며 기존 프로그래밍 교육의 문제점 해소를 위한 적절한 대안이 될 수 있을 것이다.

• 대한화학회지
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• 제44권2호
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• pp.157-165
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• 2000

청주교육대학교 과학영재교육센터에서는 과학영재를 선발하는데 화학실험평가를 실시하였다.지필평가와 더불어 실시된 화학실험 평가에서는 '각설탕의 용해 관찰하기(실험1)'와 '용액의 진하기 순서 알아 맞추기(실험2),로 명명된 두가지 실험이 이용되었다. '각설탕의 용해 관찰 실험'으로는 학생들의 기본적인 관찰 능력과 그에 따른 문제인식과 모형 사용 능력을 알아보았고, '용액의 진하기 알아 맞추기 실험 '으로는 실제적인 문제해결 능력을 알아보았다. 또한 실험 과정 중 교사의 관찰에 의해 학생들의 흥미, 과제 집착력 둥 과학적 태도도 평가하였다. 현실적으로 여려 가지 문제로 인해 실시에 어려움이 있는 실험 평가는 과학영재들이 나타내는 독특한 특성, 즉 창의성이나 유통성, 독창성을 알아보는데 도움이 되었다.

• Corrosion Science and Technology
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• 제15권3호
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• pp.120-124
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• 2016

The effect of alloying element Ca (0, 1, and 2 wt%) on corrosion resistance and bioactivity of the as-received and anodized surface of rolled plate AM60 alloys was investigated. A plasma electrolytic oxidation (PEO) was carried out to form anodic oxide film in $0.5mol\;dm^{-3}\;Na_3PO_4$ solution. The corrosion behavior was studied by polarization measurements while the in vitro bioactivity was tested by soaking the specimens in Simulated Body Fluid (1.5xSBF). Optical micrograph and elemental analysis of the substrate surfaces indicated that the number of intermetallic particles increased with Ca content in the alloys owing to the formation of a new phase $Al_2Ca$. The corrosion resistance of AM60 specimens improved only slightly by alloying with 2 wt% Ca which was attributed to the reticular distribution of $Al_2Ca$ phase existed in the alloy that might became barrier for corrosion propagation across grain boundaries. Corrosion resistance of the three alloys was significantly improved by coating the substrates with anodic oxide film formed by PEO. The film mainly composed of magnesium phosphate with thickness in the range $30-40{\mu}m$. The heat resistant phase of $Al_2Ca$ was believed to retard the plasma discharge during anodization and, hence, decreased the film thickness of Ca-containing alloys. The highest apatite forming ability in 1.5xSBF was observed for AM60-1Ca specimens (both substrate and anodized) that exhibited more degradation than the other two alloys as indicated by surface observation. The increase of surface roughness and the degree of supersaturation of 1.5xSBF due to dissolution of Mg ions from the substrate surface or the release of film compounds from the anodized surface are important factors to enhance deposition of Ca-P compound on the specimen surfaces.

• 전자공학회논문지A
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• 제30A권7호
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• pp.47-59
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• 1993

16M DRAM 용 Al/Si contact 의 열적안정성을 개선하기 위하여 "stuffed" TiN/Ti diffusion barrier를 사용하였다. Diffusion barrier 로서의 특성을 개선하기 위한 Al 증착전 TiN/Ti barrier metal의 열처리 과정중 barrier metal의 두께, 열처리온도, 분위기 등을 변화시켰다. 질소분위기하에서 450도에서 TiN(900A)/Ti(300A) 박막을 열처리 하여 "stuffed" barrier metal을 형성 시켰을 경우 Al 원자의 TiN층으로의 확산의 600도에서 후속열처리한 경우 일어났으나, 700도까지도 Al-spike를 관찰할 수 없었다. 그러나 "stuffed" barrier metal을 550도에서 형성한 경우에는 600도의 후속열처리온도에서 Al이 Si 기판으로 침투했음을 관찰하였다. 박막의 두께를 얇게한 경우, 600도의 후속 열처리에서 Al-spike가 형성되었음을 확인하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제13권9호
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• pp.4801-4805
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• 2012

This qualitative research within the project entitled "Multiprofessional Intervention and training for Ongoing Volunteer-based Community Health Programs in the Northeast of Thailand (MITV-NET)" was aimed at explaining changes of health behavior of community people in the Northeast after the intervention. The participants comprised 15 community volunteers and 27 villagers. Data were collected by indepth interview, focus group discussion, participation and non-participation observation, and note taking. Analyses were conducted in parallel with data collection, through content and comparative analysis. It was found that the health behavior fell into 2 categories: easy-to-change. The former involved fun activities joined by community people that improved their health or made them recover from illnesses after a short period without becoming addicted. These activities could be done by themselves, for example, exercising and cooking. The difficult-to-change health behavior is habitual, for example, chewing betel nuts or eating uncooked food. The following factors were found affecting behavioral changes: 1) underlying disease; 2) enjoyment in doing activities; 3) habitual behaviour; 4) improved health in a short period; 5) ability of community leaders and volunteers; and 6) community health-supporting resources. It is suggested that improving people's health requires cooperation of community people through fun activities and some initial external support. People who persist in bad habits should be encouraged to stop by showing them health deteriorating effects.

• 한국수학교육학회지시리즈E:수학교육논문집
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• 제30권3호
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• pp.335-351
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• 2016

본 연구의 목적은 '페르마 점'을 활용하여 중학교 일선에서 영재 교육을 담당하고 있는 영재 담당 교사들을 위한 교수 학습 자료를 개발하고 그 적용 사례를 분석하는 것이다. 이를 위해 연구자는 먼저 영재 교수 학습 모형, 영재프로그램의 유형에 관한 문헌을 고찰한 후 교수 학습 자료의 소재 및 주제로 페르마 점을 선정하고 이에 대한 교수 학습 자료를 개발하였다. 개발한 자료를 현장에 적용한 후 수업에 대한 피드백을 통해 자료를 수정 보완하였으며 이를 현장에 적용하였을 때 나타나는 학생들의 수학적 사고과정을 분석하였다.

• 한국항해항만학회지
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• 제40권5호
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• pp.241-247
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• 2016

The tracking filter plays a key role in the accurate estimation and prediction of maneuvering a vessel's position and velocity when attempting to enhance safety by avoiding collision. Therefore, in order to achieve accurate estimation and prediction, many oceangoing vessels are equipped with the Automatic Radar Plotting Aid (ARPA) system. However, the accuracy of prediction depends on the tracking filter's ability to reduce noise and maintain a stable transient response. The purpose of this paper is to derive the optimal values of the gain parameters used in tracking a High Dynamic Warship. The algorithm employs a ${\alpha}-{\beta}-{\gamma}$ filter to provide accurate estimates and updates of the state variables, that is, positions, velocity and acceleration of the high dynamic warship based on previously observed values. In this study, the filtering coefficients ${\alpha}$, ${\beta}$ and ${\gamma}$ are determined from set values of the damping parameter, ${\xi}$. Optimization of the damping parameter, ${\xi}$, is achieved experimentally by plotting the residual error against different values of the damping parameter to determine the least value of the damping parameter that results in the optimum smoothing coefficients leading to a reduction in the noise corruption effect. Further investigation of the performance of the filter indicates that optimal smoothing coefficients depend on the initial and average velocity of the target.