• Proceedings of the KAIS Fall Conference
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• 2003.06a
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• pp.320-321
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• 2003

최근 천연물을 중심으로 한 학문이 발전하면서 천연물이 가지는 생리활성 물질에 대한 관심이 중대되고 있다. 또한 인공합성품의 일부가 안정성의 문제가 제기되면서 천연물의 이용분야는 더욱 확대되고 있다. 급속한 경제발전과 생활수준의 향상으로 식생활을 포함한 생활방식의 다양화로 인하여 과거 감염 위주의 질병이 감소하고 선진국형의 만성퇴행성 질환이 증가하는 추세이다. 혈소판은 혈전증(thrombosis)과 지혈증(haemstasis)에서 중요한 역할을 담당하고 있는 인자로서 현관 내 병적 이상으로 인한 과도한 혈전의 생성은 뇌 -심혈관계 질환의 중요한 유발인자로 작용하므로 뇌ㆍ심혈관계 질환이나 항고지혈증을 연구하는데 유용하게 이용되고 있다. 본 연구에서는 토끼 혈액에서 분리한 세정 혈소판 부유액을 이용하여 작약 MeOH 추출물에서 분리한 천연생리활성물질들을 대상으로 혈소판 응집억제활성에 대하여 연구하였다. 작약 MeOH 추출물의 혈소판 응집억제활성 측정에서 강한 혈소판 응집억제활성 작용을 보였다. 따라서 작약 MeOH 추출물을 크로마토그라피법을 이용하여 분리하였고, NMR을 이용한 분광학적 방법으로 지금까지의 분리한 자료와 비교ㆍ분석하였다. Monoterpene glycoside 계열의 성분들인 15개의 compound와 다수의 fraction들을 HPLC를 이용하여 분리하였으며, collagen으로 유도된 혈소판 응집억제활성측정 방법에서 뛰어난 응집억제활성을 보였다. 표준물질을 이용한 HPLC 분석과 ¹H-NMR 관련 자료의 검색을 통하여 최종적으로 compound 1b가 benzoyloxy-paeoniflorin(2.6％). compound 1d가 paeond(1.3％), compound 2c가 albiflorin(3.2％), compound 2e가 paeoniflorin(33.6％)임을 확인할 수 있었다. Compound 3a의 분석결과 benzoyloxypaeoniflorin과 구조적 유사성은 있으나 동일한 구조식으로 확인할 수 없었다. 그러나 collagen에서 응집억제활성이 90％ 이상으로 뛰어난 활성을 나타내므로 benzoyloxypaeoniflorin과 유사한 구조에서 benzoyl group이 다른 작용기로 치환되었거나 R₁ group이 다른 작용기로 치환된 형태로 추측하였다. Benzoyloxypaeoniflorin은 collagen＞thrombin＞U46616＞A.A(arachidonic acid)＞PAF의 순으로 활성을 보였다. 이는 paeoniflorin의 glycoside 5-carbon위치에 위치한 OH기 대신에 benzoyl기로 치환된 benzoyl 기가 혈소판 억제 산물로 작용한 것으로 추측했다. Paeoniflorin.은 U46619＞thrombin＞collagen＞A.A＞PAF순으로 억제를 보였다. Paeoniflorin이 collagen보다 thrombin에서 강한 억제를 보이는 것으로 Ca/sup 2＋/ chelate를 형성함으로 인해 calciu 대사를 저해하는 것으로 추축했다. Compound 3a는 U46619＞collagen＞A.A＞thrombin＞PAF순으로 억제율을 보이므로 이 화합물은 paeoniflorin의 benzoyl기에 OH기가 다른 치환기로 바뀌거나 paeoniflorin의 glycoside 5-carbon 위치의 OH기 대신에 다른 작용기로 치환된 것으로 추정하였다. 이러한 결과로 작약의 주성분인 paeoniflorin과 유사한 구조를 가진 다른 monoterpene glycoside 계열의 화합물들과 비교 분석하고 구조를 화인하고 이들 성분이 어떻게 혈소판 응집억제활성에 작용하는지를 연구하였다.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.18 no.5
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• pp.34-48
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• 2019

The purpose of this study was two-fold; first, to develop safety performance functions (SPF) using transportation-related big data for all types of roads in Korea were developed, Second, to provide basic information to develop measures for relatively dangerous roads by evaluating the safety grade for various roads based on it. The coordinates of traffic accident data are used to match roads across the country based on the national standard node and link system. As independent variables, this study effort uses link length, the number of traffic volume data from ViewT established by the Korea Transport Research Institute, and the number of dangerous driving behaviors based on the digital tachograph system installed on commercial vehicles. Based on the methodology and result of analysis used in this study, it is expected that the transportation safety improvement projects can be properly selected, and the effects can be clearly monitored and quantified.

• The Journal of the Acoustical Society of Korea
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• v.26 no.2
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• pp.61-68
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• 2007

The frequency response of a microphone, which indicates the frequency range that a microphone can output within the approved level, is one of the most significant standards used to measure the characteristics of a microphone. At present, conventional methods of measuring the frequency response are complicated and involve the use of expensive equipment. To complement the disadvantages, this paper suggests a new algorithm that can measure the frequency response of a microphone in a simple manner. The algorithm suggested in this paper generates the Optimized Aoshima's Time Stretched Pulse(OATSP) signal from a computer via a standard speaker and measures the impulse response of a microphone by convolution the inverse OATSP signal and the received by the microphone to be measured. Then, the frequency response of the microphone to be measured is calculated using the signals. The performance test for the algorithm suggested in the study was conducted through a comparative analysis of the frequency response data and the measures of frequency response of the microphone measured by the algorithm. It proved that the algorithm is suitable for measuring the frequency response of a microphone, and that despite a few errors they are all within the error tolerance.

• The Journal of the Acoustical Society of Korea
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• v.27 no.4
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• pp.163-170
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• 2008

Most of receiving rooms for the measurement of floor impact sound have rectangular shapes with couple of meters of dimension, with reflective finishing, no furniture, no curtains. Modal overlaps in those condition are the major reason for the low reproducibility, and as a matter of course, the low credibility. It is the major purpose of this study that searching for a better measurement method which mitigate the effect of modal overlap on measurement. Two ways of methods are tested. One is the way described in ISO standards which enables controlling the room modes of receiving rooms, the other is the way which enables to get more precise spatial averages in receiving rooms with room modes. It is not easy maintaining the reverberation time of low frequency bands in the range between 1s and 2s, though it is proven to be effective controlling the room modes with base traps. Space-time average SPL's through combinations of rotating microphones are easy to measure, and have good consistencies with average SPL of entire receiving room.

• Progress in Medical Physics
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• v.17 no.1
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• pp.24-31
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• 2006

Automated analysis software was developed to measure the magnitude of the intrafractional and interfractional errors during breast radiation treatments. Error analysis results are important for determining suitable planning target volumes (PTV) prior to Implementing breast-conserving 3-D conformal radiation treatment (CRT). The electrical portal imaging device (EPID) used for this study was a Portal Vision LC250 liquid-filled ionization detector (fast frame-averaging mode, 1.4 frames per second, 256X256 pixels). Twelve patients were imaged for a minimum of 7 treatment days. During each treatment day, an average of 8 to 9 images per field were acquired (dose rate of 400 MU/minute). We developed automated image analysis software to quantitatively analyze 2,931 images (encompassing 720 measurements). Standard deviations ($\sigma$) of intrafractional (breathing motion) and intefractional (setup uncertainty) errors were calculated. The PTV margin to include the clinical target volume (CTV) with 95% confidence level was calculated as $2\;(1.96\;{\sigma})$. To compensate for intra-fractional error (mainly due to breathing motion) the required PTV margin ranged from 2 mm to 4 mm. However, PTV margins compensating for intefractional error ranged from 7 mm to 31 mm. The total average error observed for 12 patients was 17 mm. The intefractional setup error ranged from 2 to 15 times larger than intrafractional errors associated with breathing motion. Prior to 3-D conformal radiation treatment or IMRT breast treatment, the magnitude of setup errors must be measured and properly incorporated into the PTV. To reduce large PTVs for breast IMRT or 3-D CRT, an image-guided system would be extremely valuable, if not required. EPID systems should incorporate automated analysis software as described in this report to process and take advantage of the large numbers of EPID images available for error analysis which will help Individual clinics arrive at an appropriate PTV for their practice. Such systems can also provide valuable patient monitoring information with minimal effort.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.4
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• pp.259-264
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• 2002

DK 754S, a forage corn hybrid is bred by Dekalb plant Genetics Co.. Garst 8255 by Garst Seeds Co., and GW 737 by Crosbyton Co. in US, respectively. These have been tested in Suwon and Chonan for 3 years to test their regional yield trial. In result, we were able to confirm the excellence of above cultivars and these were selected as new recommended cultivars April of 2002 by NACF. The characteristics of these cultivars are as follows ; 1. DK 7545 a. This cultivar is mid-late maturing, high quality, high yielding forage corn hybrid. Its mean tasseling date is the 11th of July. It takes 78 days from emergence to tasseling date, which is almost same with Kwanganok. The culm length and the ear height are 231 cm and 127 cm. It is relatively strong to lodging. b. The color of ear is yellow, the number of ear row is nineteen. DK 7545 shows strength to H maydis and MBSDV has occurred between 0% and 4.1% in Chonan test area but it still does not affect yielding at all. It is relatively resistant to corn borer and its stay green is almost same level comparing to a check hybrid, Kwanganok. c. Dry matter yield of this cultivar is 19.6 tons, TDN is 13.4 tons per a ha, therefore these hybrids are increased by from 6 to 9% comparing to Kwanganok. The percent ear among total dry matters yield is 43.7%. 2. Garst 8255 a. This hybrid is mid-late maturing, high quality, high yielding forage corn like as Kwanganok. Its the mean tasseling date and the period from emergence to tasseling date are almost same with a check hybrid, Kwanganok. The Culm length and the ear height are 259 cm, and 146 cm which are tall. It resists to lodging and shows excellence of stay green. b. Garst 8285 resists to H maydis, and MBSDV, and corn borer as much as Kwanganok has. c. Dry matter yield of this cultivar is 21,735 kg. TDN is 14,627 kg per a ha, therefore this is increased by 21%, 16%, respectively, comparing to a check hybrid, Kwanganok. The percent ear among total dry matters yield is 44.2%. 3. GW 737 a. This hybrid is mid-late maturing, high quality, high yielding forage com hybrid like as Kwanganok. Its mean tasseling date is 13th of July which is 2 days late comparing with a check hybrid, Kwanganok and the period from emergence to tasseling date is 80 days. b. The culm length and the ear height are 274 cm and 150 cm, which are tall. It resists to lodging moderately and shows excellence of stay green. c. GW 737 resists to H maydis and MBSDV very well, corn borer moderately resistance. d. Dry matter yield of this cultivar is 18,025kg, TDN 15,164kg per a ha, therefore this hybrid remarkably increased by 26%, 20%, respectively, comparing to a check hybrid, Kwanganok.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.2
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• pp.165-170
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• 1994

High quality rapeseed cultivars including Nojeokchae, Yeongsanyuchae Halla-yuchae and Tamrayuchae have been released and recommended as a zero erucic acid variety to Cheju farmers for 13 years, where is a major rapeseed production area in korea. However, rapeseeds produced in Cheju island in 1992 and 1993 contained 47.7% and 37.0% of erucic acid respectively resulting in poor quality oil being not adequate for edible oil. It was considered that the zero erucic acid varieties did not have an opportunity to be cultivated in Cheju island by farmers living in the Island. Thus, the new rapeseed varieties without erucic acid should be bred and recommended to the farmers of southern area of Korea as a multiple cropping crop just after rice harvest, and for large scale mechanized and labour-serving rapeseed culture. The change of rapeseed breeding goal would be desirable for fatty acid composition improvement of rapeseed to develop varieties adaptable to southern part of Korea, and to produce rapeseed oil directly used as an edible oil safely.

• Journal of the Korean Chemical Society
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• v.55 no.3
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• pp.418-429
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• 2011

Novel chromium(III), manganese(II), iron(III), cobalt(II), nickel(II), copper(II), ruthenium(III), and zirconyl(II) complexes of $N^1,N^2$-bis(3-((3-hydroxynaphthalen-2-yl)methylene-amino)propyl)phthalamide ($H_4L$, 1) have been synthesized and characterized by elemental, physical, and spectral analyses. The spectral data showed that the ligand behaves as either neutral tridentate ligand as in complexes 2-5 with the general formula $[H_4LMX_2(H_2O)]{\cdot}nH_2O$ (M=Cu(II), Ni(II), Co(II), X = Cl or $NO_3$), neutral hexadentate ligand as in complexes 10-12 with the general formula $[H_4LM_2Cl_6]{\cdot}nH_2O$ (M=Fe(III), Cr(III) or Ru(III)), or dibasic hexadentate ligand as in complexes 6-9 with the general formula $[H_2LM_2Cl_2(H_2O)_4]{\cdot}nH_2O$ (M = Cu(II), Ni(II), Co(II) or Mn(II), and 13 with general formula $[H_4L(ZrO)_2Cl_2]{\cdot}8H_2O$. Molar conductance in DMF solution indicated the non-ionic nature of the complexes. The ESR spectra of solid copper(II) complexes 2, 5, and 6 showed $g_{\parallel}$ >g> $g_e$, indicating distorted octahedral structure and the presence of the unpaired electron in the $N^1,N^2$ orbital with significant covalent bond character. For the dimeric copper(II) complex $[H_2LCu_2Cl_2(H_2O)_4]{\cdot}3H_2O$ (6), the distance between the two copper centers was calculated using field zero splitting parameter for the parallel component that was estimated from the ESR spectrum. The antibacterial and antifungal activities of the compounds showed that, some of metal complexes exhibited a greater inhibitory effect than standard drug as tetracycline (bacteria) and Amphotricene B (fungi).

• Korean Chemical Engineering Research
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• v.60 no.4
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• pp.535-543
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• 2022

A CPFD (Computational particle fluid dynamics) model of solar fluidized bed receiver of silicon carbide (SiC: average d_p=123 ㎛) particles was established, and the model was verified by comparing the simulation and experimental results to analyze the effect of particle behavior on the performance of the receiver. The relationship between the heat-absorbing performance and the particles behavior in the receiver was analyzed by simulating their behavior near bed surface, which is difficult to access experimentally. The CPFD simulation results showed good agreement with the experimental values on the solids holdup and its standard deviation under experimental condition in bed and freeboard regions. The local solid holdups near the bed surface, where particles primarily absorb solar heat energy and transfer it to the inside of the bed, showed a non-uniform distribution with a relatively low value at the center related with the bubble behavior in the bed. The local solid holdup increased the axial and radial non-uniformity in the freeboard region with the gas velocity, which explains well that the increase in the RSD (Relative standard deviation) of pressure drop across the freeboard region is responsible for the loss of solar energy reflected by the entrained particles in the particle receiver. The simulation results of local gas and particle velocities with gas velocity confirmed that the local particle behavior in the fluidized bed are closely related to the bubble behavior characterized by the properties of the Geldart B particles. The temperature difference of the fluidizing gas passing through the receiver per irradiance (∆T/I_DNI) was highly correlated with the RSD of the pressure drop across the bed surface and the freeboard regions. The CPFD simulation results can be used to improve the performance of the particle receiver through local particle behavior analysis.

• Journal of Animal Environmental Science
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• v.10 no.2
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• pp.87-92
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• 2004

This research was carried out to investigate the effects of ozone and anion treatments in improving the quality of the drinking water far livestock. The drinking water was treated with an ozone concentration of 0.658 $\~$0.722 g/h and with anion of 3.27 $\~$ 6.17$\times$1,000,000 pieces/sec. With the ozone and anion treatments, the pH was significantly increased from a range of pH 6.38 $\~$ 7.14 to a range of pH 7.5 $\~$ 7.8(P<0.05). Also, with the ozone and anion treatments, the dissolved oxygen (DO) concentration in the drinking water was increased from a range of 2.0 $\~$ 3.5 mg/$\iota$ to 5.5 $\~$ 6.1 mg/$\iota$(P<0.05): the DO decreased in the control. The dissolved ozone was not increased in the beginning of the experiment, but was increased by 0.48$\~$0.56 mg/L after 48 h of the ozone and anion treatment. The colony numbers of Staphylococcus aureus, Salmonella enteritis, and Escherichia coli disappeared after one hour of ozone and anion treatment.