• 한국작물학회지
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• 제42권3호
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• pp.352-356
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• 1997

우리 나라 농가포장에 현재까지 잡초성 벼인 앵미가 잔존하게된 경로를 추정하고자 앵미 발생이 극심한 농가포장을 선정하여 전체 개체에 대한 앵미 발생비율, 단위면적당 앵미 개체수, 이앙재배와 직파재배 포장에서의 앵미 발생 위치 등을 조사하여 다음과 같은 결과를 얻었다. 1. 이앙재배 포장에서 앵미 발생율이 가장 높았던 것은 5.5％였다. 2. 직파재배 포장의 앵미 발생이 이앙재배 포장보다 많았다. 3. 이앙재배 포장에서는 앵미가 대부분 재배벼 주내에 혼입되어 있었으나, 골뿌림 직파재배 포장에서는 골 사이에 발생한 앵미 개체가 많았다. 4. 비장려품종 재배 포장에서의 앵미 발생이 장려품종 재배 포장보다 많았다. 5. 이앙재배에서 앵미는 대부분 재배벼 종자에 혼입되어 잔존하였고, 극히 일부는 자연탈립에 의하였으며, 직파재배에서는 자연탈립에 의한 앵미 발생이 종자혼입에 의한 발생보다 많았다.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2009년도 정기총회 및 동계학술연구발표회
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• pp.217-219
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• 2009

A GMI magnetic field sensor working based on time-coded principle has been investigated and designed. The laboratory model has been constructed and tested carefully, demonstrating the sensitivity of $3\;{\mu}s/{\mu}T$ in the field range of ${\pm}100\;{\mu}T$. An amorphous thin wire, $100\;{\mu}m$ in diameter ${\times}50\;mm$ in length, was chosen to be sensing element which was fit into a small field modulation coil of 60 mm in length. The sensor is working based on a time-coded principle that, with the magnetic field modulation was chosen in range of hundreds of Hz, the change in time interval of two adjacent GMI peaks relating to external DC magnetic field is proportional to the intensity of the external field to be measured. This mechanism has made a great improvement to the linearity of the sensor.

• 한국조리학회지
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• 제12권3호
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• pp.75-90
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• 2006

The purpose of this study is to understand how to activate field training internships through former researches related to training internships. The concept of field training is the same as education of work experience. Students have experienced the skills of practical jobs in the tourism industry and could enhance acquisition of professional theories. According to domestic former researches, students who participated in hotel field practice hardly satisfied with internships due to unreasonable duties, burdens and circumstances regardless of efficiency of school curriculum. Also, they showed dissatisfaction with compensation. However, foreign studies have only focused on communication between hotels and schools. Finally, in order to activate industrial field training internships, schools and hotels have more delicate harmonization to address training internship problems. In addition, promoting field training internships must include proper incentives and must be supported by school. And also the hotel management must offer incentives to the students who are under field training internships in the hotel. From internship programs, students could get much more benefits in hotel job application.

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2003년도 종합학술발표회 논문집 Vol.13 No.1
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• pp.13-17
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• 2003

In this paper, the design parameters for the magnetic field source at extremely low frequency are proposed. This facility can be used for in vivo experiments with small animals to investigate biological response to the driving magnetic fields. In case that the exposed animals are motionless, the animals may be affected by the directivity of driving field. To avoid this effect, a 2-axis ELF magnetic field driving apparatus was designed, The optimum location and number of turns of each coil were obtained by numerical analysis. Applying these data to the MATLAB code (for computation), the magnetic field distribution was obtained. The calculation result for a well-designed facility showed that the space in which the amplitude of the magnetic field lies within the 95% of the magnetic field distribution was more than 60% of each axis length.

• 한국주조공학회지
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• 제20권2호
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• pp.129-140
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• 2000

This study aims at the phase-field modeling of the phase transformation in graphitization of the cast iron. As the first step, we constructed a phase-field model including the phases with negligible solubility. Under the dilute regular solution approximation, a simplified version of the phase-field model was obtained, which can be used for the phase transformation related with the stoichiometric phases. The results from the numerical calculation of the phase-field model was in good agreement with the exact analytic solution. The compositional shift due to Gibbs-Thomson effect can be reproduced within 0.5% error in the numerical calculation. The interface velocity, whereas, in numerical calculation of phase-field model appeared to be 15% larger than that from the analytic solution. This error is due to the shift of the interface position in phase-field model from the position with ${\phi}=0.5$.

• 천문학회보
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• 제44권1호
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• pp.43.3-43.3
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• 2019

Magnetic fields play an important role in supporting molecular clouds against gravitational collapse. The measured magnetic field strengths in molecular clods enable us to see the effect of magnetic fields in star-forming regions. People have used the Chandrasekhar and Fermi (CF) method to estimate magnetic field strength from observational quantities of molecular cloud density, turbulent velocity and polarization angle dispersion. However, previous studies obtained just one magnetic field strength over the quite large region of a molecular cloud by using the CF method. We here suggest a way to estimate magnetic field strength distribution in Orion A region. We used 450 and 850-micron polarization data of James Clerk Maxwell Telescope (JCMT). Magnetic field strengths were estimated in two wavelengths with 4 pixel resolutions of 16, 20, 24 and 28". Through statistical analysis, we proved the difference of magnetic field strengths between two wavelengths were caused by the difference of their beam sizes. Additionally, we calculated the radii of curvature of polarization segments to select a best pixel resolution for estimating the magnetic field distribution. The pixel resolution should be larger than a radius of curvature. We selected that 20 or 24" pixel resolutions are good choices towards Orion A region.

• 한국초전도ㆍ저온공학회논문지
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• 제17권2호
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• pp.31-35
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• 2015

Mapping is a useful tool in the magnetic field analysis and design. In some specific research area, such as the nuclear magnetic resonance (NMR) or the magnetic resonance imaging (MRI), it is important to map the magnetic field in the interesting space with high accuracy. In this paper, an indirect mapping method in the center volume of an air-core solenoid is presented, based on the solution of the Laplace's equation for the field. Through the mathematical analysis on the mapping calculation, we know that the condition number of the matrix, generated by the measurement points, can greatly affect the error of mapping result. Two different arrangement methods of the measurement points in field mapping are described in this paper: helical cylindrical line (HCL) method and parallel cylindrical line (PCL) method. According to the condition number, the HCL method is recommended to measure the field components using one probe. As a simple example, we mapped the magnetic fields in a MRI main magnet system. Comparing the results in the different methods, it is feasible and convenient to apply the condition number to reduce the error in the field mapping calculation. Finally, some guidelines were presented for the magnetic field mapping in the center volume of the air-core solenoid.

• 대한안전경영과학회지
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• 제17권2호
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• pp.177-182
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• 2015

Many students can experience, such as for credit and social activities through field trips and participate in field trips. For on-site field training exercise participants currently in Gwangju University They take part in field trip 1, 2, 3 and 4 as the type.. Field Practice 1 type in summer and 2 in winter of 4-week period during vacation holidays with 3 credits, field trips 3 type of 8-week period during vacational holidays with 6 credits recognized for \400,000 in job training fee is also payable by the Leaders in INdustry-university Cooperation Agency. 4 types of job training are fourth grade (Architecture Grade 5) can be employed in conjunction for more than 15 weeks and admitted to the second semester of 15 credits by participating in job training. For most schools, but to pay a fee-job training at the University of Hanyang University, Kyungpook National University has a student assistance in the field training participating companies. This establishment does not have a clear idea of the legal entities responsible in the event of industrial accidents. Academic research is also nonexistent state for them. In this paper, we distinguish the personality for it via the existing labor precedents with respect to the legal responsibility of an industrial accident. This aims at putting the means to establish the role of the University of job training support.

• Radiation Oncology Journal
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• 제12권2호
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• pp.263-267
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• 1994

In clinical radiotherapy, the use of wide and irregular field techniques frequently results in considerable tumor dose inhomogeneity because of, the variation in physical characteristics of irradiated volumes. This report describes an analysis of the dosimetry of the irregular fields such as radiation fields for Hodgkin's disease(mantle field), esophageal cancer, and lung cancer when a 6 MV and a 15 MV linear accelerators are utilized. Doses were measured in a Rando phantom using methods of thermoluminescence dosimetry(TLD), and were calculated by radiotherapy planning computer system with the Clarkson's method for calculation of a irregular field. A dose variation of $5-22\%,\;6-9\%,\;6-14\%$ were found in the mantle field, esophageal cancer field, lung cancer field respectively. Higher doses occurred in the superior portion of the irregular field. The sites of maximum dose variation were the supraclavicular and the upper spinal cord region. To adjust for these substantial differences, a compensator or a shrinking field technique should be adopted.

• 대한안전경영과학회지
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• 제17권3호
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• pp.1-7
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• 2015

The study conducted questionnaire analysis to 413 industrial safety field employees in order to examine the necessity and validity of industrial safety field's 17th neo-job classification based on National Competency standards(NCS). As a result, 50.1% of industrial safety management field and 43.3% of industrial health management field answered that classification details of occupational safety and health management field are classified by job(duty) performance. Industrial safety management field recognizes that management and engineering section play a significant role in their work, while industrial health management field recognizes worker's health care and work environment management and overall control of work environment assessment to be significant in their work. Furthermore, industrial safety management field recognizes that separating qualification and foundation of 'construction safety manager', 'chemicals(safety and health) manager', '(toxic)risk assessment evaluator or risk factor manager' to be highly significant. The study is meaningful in that it suggests industrial safety field's qualification items practical in industrial sites.