• 원예과학기술지
• /
• 제17권4호
• /
• pp.470-472
• /
• 1999

세계 각 종묘회사에서 수집된 교배종 당근의 웅성부임(雄性不稔) 형태와 그 분리비(分離比)를 조사한 결과 지역별, 회사별, 품종그룹별로 사용된 웅성부임(雄性不稔) 형태에 차이가 있었다. 즉, 미국의 종묘회사는 Imperater계 품종이 대부분이며 petaloid형의 웅성부임(雄性不稔)을 주로 이용하였고 Nantes계 품종이 대부분인 유럽의 종묘회사는 brown anther형의 웅성부임(雄性不稔)을 주로 이용하였지만 이들 중 일부 회사에서 Nantes계의 특성에서 벗어나는 품종에서 petaloid형도 이용하고 있었다. Chantaney, Kuroda계 품종이 대부분인 일본(日本), 한국의 경우에는 petaloid형, brown anther형 두 가지 모두 이용하지만 각 회사별로는 한가지 형태의 웅성부임(雄性不稔)을 주로 이용하고 있었다. 한 품종에서는 한가지 형태의 웅성부임(雄性不稔)만 나타났는데 이는 웅성불임의 형태가 세포질의 종류에 따라 결정된다는 다른 연구자의 결과와 일치하는 것으로 나타났다. 한편 국내에서 이용되는 당근 계통들 중 서로 다른 두 가지 세포질(Sa, Sp)에 대해 유지친으로서의 사용 가능성이 어느 정도되는지 알아보기 위하여 여교잡하였을 때 petaloid형 세포질(Sp) 에서는 20계통 중 75%인 15계통에서 유지친을 찾을 수 있어 유지친의 분포빈도가 높은 것을 알 수 있었으며 brown anther형 세포질(Sa)에서는 4계통 중 3 계통에서 유지친을 찾을 수 있었지만 여교잡 된 소재(素材)가 매우 한정되어 분포빈도를 말하기는 어렵다고 판단되었다.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1999년도 하계학술대회 논문집 E
• /
• pp.2041-2043
• /
• 1999

In order to investigate the radiation characteristics of unmixed line noise from overhead high voltage AC transmission lines, a gap noise generator was manufactured. Disk size which decides capacitance between the noise generator and earth was selected through preliminary indoor experiments and analysis by charge simulation method. The capacitance is one of principal parameters related to inject a proper noise current into lines. The field experiments were performed with the noise generator installed in Kochang 765 kV full scale test line. As the results, the useful data which can be used to analysis the radiation characteristics of noise from transmission lines was obtained. Those are lateral profiles the directivity of antenna toward lines, frequency spectra and so on.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1998년도 하계학술대회 논문집 E
• /
• pp.1647-1649
• /
• 1998

This paper describes the power frequency voltage and its countermeasure when a 765 kV transmission line is directly connected to a 345 kV line and operated at 345 kV voltage. The summary of this result is as follows : The western route of 765 kV transmission line doesn't need any countermeasure to reduce the power frequency voltage at the receiving end. The eastern route of 765 kV transmission needs 100 Mvar(3 phase) capacity of shunt reactor at the receiving end to reduce the power frequency voltage. The use of shunt reactors in the 765 kV transmission lines has unexpected problems, one of which is induction of high voltages on a de-energized circuit of two parallel lines. This paper examined the problem of resonance on two parallel transmission circuits in one routes.

• Journal of Electrical Engineering and Technology
• /
• 제9권3호
• /
• pp.991-996
• /
• 2014

Power frequency magnetic field is still a critical problem for new construction of overhead power transmission lines in Korea because most people have been concerned about possibly carcinogenic effects of it. Although reference level of power frequency(60Hz) magnetic field has been set to 200uT in ICNIRP guidelines published in 2010, Korean government has no intention of adjusting 83.3uT specified by law in 2006 to this new reference level in consideration of people's concerns for the time being. Regardless of the current regulated magnetic field value, electric utility company has been trying to reduce magnetic field in the residential area in the vicinity of overhead power transmission lines to take into account of public concerns on the long-term effect of magnetic fields. In an effort to reduce magnetic field, engineering side has made considerable efforts to develop passive loop based, cost-effective mitigation technique of power frequency magnetic field more than ten years. In order to verify developed power frequency magnetic field mitigation technique based on passive loop, a horizontal type of passive loop was designed and installed for commercially operating 154kV overhead power transmission line for the first time in Korea. The measurement results before and after the installation of passive loop showed that magnetic field could be reduced to about 20%. The electrical environmental effects such as AN, RI and TVI were assessed before and after the installation of passive loop and these values were complied with the requirements specified by electric utility. It has been confirmed from the field test results that passive loop could be commercially and cost-effectively utilized to mitigate power frequency magnetic field.

• 생명과학회지
• /
• 제16권3호
• /
• pp.527-533
• /
• 2006

벼의 약 및 현미 배양효율과 관련된 DNA marker를 이용하여 인디카형 벼 품종인 'IR 36'의 조직배양 효율을 개선하기 위하여 실험한 결과를 요약하면 다음과 같다. MGRI집단의 약배양에서 식물체분화율이 높은 계통으로 선발된 'MGRI 079'와 'MGRI 036'의 약배양 효율은 각각 19.8%, 19.9%로 가장 높게 나타났다. 'MGRI 079'에 'IR 36'이 여교배되어 양성된 $BC_2F_4$ 100 계통에 대한 marker 검정을 실시하여 선발된 34 계통중 약배양에서 캘러스 형성률이 'IR 36'보다 높은 계통은 30계통이었고, 현미배양에서 'IR 36'보다 식물체 분화율이 높은 계통은 $BC_2F_4-28$ 외 14 계통이었다. $BC_2F_4$ 34계통 중에서 식물체분화능력이 높은 계통으로 선발된 $BC_2F_4-28$은 간장이 'IR 36'보다 큰 편이었으나 출수기와 미립특성은 'IR 36'과 비슷하였다. 'MGRI 036'에 'IR 36'을 반복친으로 여교배하여 양성된 $BC_4F_3$ 50계통의 현미배양을 실시한 결과 'IR 36'보다 식물체 재분화율이 높은 계통은 $BC_4F_3-3$ 외 10 계통이었고, 그중 $BC_4F_3-46$의 식물체 재분화율이 11%로 가장 높게 나타났다.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 1999년도 하계종합학술대회 논문집
• /
• pp.223-226
• /
• 1999

We study the propagation property of the transient signals along the microstrip using the wavelet transform. Wavelet transform can offer the time-frequency windows. It makes the resolution of time high in high frequency range and the resolution of frequency high in low frequency range. So It is useful to analyze the signals which have both low and high frequency components.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2003년도 하계학술대회 논문집 A
• /
• pp.519-521
• /
• 2003

This paper presents a frequency analysis of subspan oscillation on overhead transmission line. The Oscillation frequency is a natural characteristic of a subspan and can be calculated. But it is not same to calculated frequency, because it has been composed several frequencies of adjacent subspan. We were analyzed to the frequency of subspan oscillation by FFT methods. This result will use to establish of the subspan location rules.

• 한국의류산업학회지
• /
• 제23권4호
• /
• pp.527-535
• /
• 2021

In this study, electroconductive textiles were developed by screen-printing technology using a complex solution of PEDOT:PSS/AgNW on a polylactic acid nanofiber web. A performance evaluation was then conducted to utilize this electroconductive textile as a signal transmission line. To obtain highly conductive electroconductive textiles, this study sought to determine the optimal mixing ratio of PEDOT:PSS/AgNW. Sheet resistance was measured to evaluate the electrical properties of electroconductive textiles, Finite element-scanning electron microscopy images were then used to examine surface properties, and Fourier transform-infrared analysis was performed to evaluate chemical properties. The signal waveform characteristics of the electroconductive textile were observed using a signal generator and an oscilloscope. Radio-frequency characteristics were then evaluated to confirm frequency range, and bending tests were conducted to evaluate durability. The signal transmission lines produced in this study had a sheet resistance value of 3.30 ?/sq, and signal transmission performance was evaluated to observe that the input value of the voltage was nearly identical to the output value. In addition, S21 analysis confirmed that it was available in the frequency domain up to 35 MHz. The performances of the transmission lines were maintained after 100, 200, 500, and 1,000 repeated bending tests, and sufficient durability was confirmed.

• 한국작물학회지
• /
• 제43권4호
• /
• pp.250-253
• /
• 1998

Somaclonal variation was observed in the field on doubled haploid plants derived from single pollen of a rice cultivar "Hwaseongbyeo". The variations of seven quantitative traits including plant height and one qualitative trait (pubescence) in 436 lines ($R_2$ generation) were analyzed. The number of lines which fell beyond the boundaries of the 95% confidence intervals of the check variety, Hwaseongbyeo was checked for each quantitative trait, and of those fertility showed the highest variation frequency (85.6%), followed by plant height (77.5%), flag leaf length (66.5%), grains per panicle (42.2%), days to heading (34.5%), panicle length (30.7%) and panicles per hill (22.7%). And the variations of quantitative traits except days to flowering appeared to move in the negative direction compared to "Hwaseongbyeo". Variability within lines was also observed for quantitative and qualitative traits. Twenty-nine $R_2$ lines (7%) segregated for pubescence and 130 $R_2$ lines (30%) showed variation with regard to fertility. This suggests that mutations usually occur before diploidization. Twenty-nine $R_2$ lines representing a wide spectrum of variation were chosen for RAPD analysis. The number of lines showing DNA polymorphism compared to Hwaseongbyeo ranged 0 from to 10 according to the primer used and this seems to indicate that specific loci have highly mutable genomic site.utable genomic site.

• Journal of Electrical Engineering and Technology
• /
• 제13권4호
• /
• pp.1655-1662
• /
• 2018

This paper studies the magnetic fields between the power lines which are finite length and other ones which are infinitely long around the first tower in the proximity of the power transformers. They will be used as a source of disturbance applied to the power line. The method applied in this study was gradual; develop the theoretical formulation of the magnetic fields of these lines which are finite length and other ones which are infinitely long, examine the effects of different couplings between the different neighboring lines and the distribution transformers on behavior of magnetic fields. The method also focused on the experimental results analyzing the magnetic fields which will be used as a source applied to the auditory implants EMC. The theoretical and experimental results were compared and discussed for three power lines (90kV, 150kV and 225kV) near the power station, and it proved the effect of these substations on the simulated and measured results of the magnetic field. The maximum intensities of magnetic fields measured at the height of 1m from the ground for the circuit of three lines close to each substation were significantly lower than the ICNIRP reference levels for occupational and non occupational exposures.