• Food Science and Biotechnology
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• v.15 no.6
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• pp.942-947
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• 2006

The effect of oat bran extracts on the formation of aberrant crypt foci (ACF) in the colon induced by 1,2-dimethylhydrazine (DMH) was studied in F344 male rats. Extracts were prepared using various combinations of temperature (40, 45, 50, 55, or 60$^{\circ}C:\;X_1$), ethanol concentration (0,5, 10, 15, or 20%: $X_2$), and pH (5, 6, 7, 8, or 9: $X_3$). Among the various extracts tested, one ethanol extract (EE; $45^{\circ}C$, 15% ethanol at pH 6) and one water extract (WE; $50^{\circ}C$ at pH 5) were selected based on their in vitro antitumor activity. The animals were fed with basal diet alone or basal diet supplemented with 0.25 or 0.5% of EE or WE for 6 weeks. During the initial 2 weeks of the 6-week test period, the rats were subcutaneously injected with DMH (30 mg/kg) 4 times for the induction of ACF. DMH induced an average of 322.7 and 142.9 aberrant crypts (AC) and ACF, respectively. A low dose (0.25%) of EE (containing 38.3% ${\beta}$-glucan) and WE (containing 22.8% ${\beta}$-glucan) greatly reduced the numbers of DMH-induced AC and ACF. Significantly, ACF consisting of more than 3 AC were reduced by half in which the effect of EE, containing a higher concentration of ${\beta}$-glucan, was superior to that of WE. These results demonstrate that oat bran extracts may confer protection against colon carcinogenesis.

• Applied Biological Chemistry
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• v.38 no.5
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• pp.463-467
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• 1995

In vitro metabolism study of ${\alpha}$-endosulfan by liver and kidney microsomal cytochrome P-450 monooxygenase system of the mouse(Balb/C) was performed. ${\alpha}$-Endosulfan was metabolized to endosulfan lactone(EL), endosulfan hydroxyether(EHE), endosulfan alcohol(EA), endosulfan sulfate(ES), endosulfan ether(EE) and ${\beta}$-endosulfan(${\beta}$-E). The main metabolites of ${\alpha}$-endosulfan were EL(13.2%) and EA(11.5%) in liver microsome and EA(17.4%) md EHE(19.3%) in kidney microsome. The $^{14}C$-activity of organic extractable fraction and water soluble fraction were 63.4% and 31.7% in liver micosome incubates respectively. The water soluble metabolites were EA(83.9%), EHE(4.5%) and ES(2.3). Piperonyl butoxide treatment inhibited the formation of EE by 86%, EA by 92% and EHE, EL and ES were barely formed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.15
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• pp.1-31
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• 1974

Introducing genes for earliness of wheat varieties is important to develop early varieties in winter wheat. In oder to obtain basic informations on the response of heading to the different day length and temperature treatments and on the inheritance of heading dates, experiments were conducted at the field and greenhouse of the Crop Experiment Station, Suwon. Varieties used in this experiments were, early variety Yecora F70, medium varieties Suke #169, Parker and Yukseung #3, and late varieties Changkwang, Bezostaia, Sturdy and Blueboy. The parents and F$_1$s of partial diallel crosses of above eight varieties were subjected the following four different treatments; 1. high temperature and long day, 2. high temperature and short day, 3. low temperature and long day, and 4. low temperature and short day. The same materials were grown also in field condition. Parents, F$_1$ and F$_2$ generation were grown also in both greenhouse under high temperature and short day and in field. The results obtained were summarized as follow: 1. No effects of temperature and daylength on the number of leaves on the main stem were found when -varieties were vernalized. The number of main stem leaves were fewer for spring type of varieties than for winter type of varieties. 2. The effects of temperature and daylength on the days to flag leaf opening were dependent on the speed of leaf emergence. The speed of leaf emergence were faster for lower leaves than for upper leaves. 3. The response to short day and long day (earliness of narrow sense) of varieties were found to be direct factor responsible to physiology of heading dates in vernalized varieties. Great difference of varieties to heading date was found in high temperature and short day treatment, but less differences were found in high temperature and long day, low temperature and long day and low temperature and short day treatments respectively. The least varietal difference for heading dates was found in the field condition. 4. Changkwang and Parker were found to be the most sensitive to short day treatment (photosensitive) and the heading of these varieties were delayed by short day treatment. No great varietal differences were found among other varieties. 5. Varietal differences of heading dates due to daylength were greater in high temperature than in low temperature. 6. Varietal differences of heading dates due to temperature were not great. but in general the heading dates of varieties were faster under high temperature than under low temperature. 7. Earliness of heading dates was due to partial dominance effect of genes involved in any condition. The degree of dominance was greater under short day than under long day treatment. 8. The varietal differences of heading date under high temperature and long day were due to earliness or narrow sense (response to long day) of varieties. The degree of dominance was greater for Yecora F70, spring type than for other winter type of varieties. No differences or less differences of degree of dominance was found among winter type of varieties. The estimated number of effective factor concerned in the earliness of narrow sense was one pair of allele with minor genes. 9. The insensitivity of varieties to short day treatment in heading dates was due to single dominant gene effect. Under the low temperature the sensitivity of varieties to short day treatment was less apparent. 10. The earliness of short day and long day (earliness of narrow sense) sensitivities of varieties appearea to be due to partial dominance of earliness over lateness. In strict sense, the degree of the dominance should be distinguished. 11. Dominant gene effects were found for the thermo-sensitivity of varieties, and the effect was less, significant than the earliness in narrow sense. 12. One pair of allele, ee and EE, for photosensitivity was responsible for the difference in the heading dates between Changkwang and Suke #169. Two pairs of alleles, ee, enen and EE, EnEn. appeared to be responsible for the difference between Changkwang and Yecora F70. The effects of EE and EnEn were, additive to the earliness and the effects of EE were greater than EnEn under short day. However, the effects of EE were not evident in long day but the effects of EnEn were observed in long day. 13. Two pairs of dominant alleles for the earliness were estimated from the analysis of F$_1$ diallels in the field but the effects of these alleles in F$_2$ were not apparent due to low temperature and short day treatment in early part of growth and high temperature and long day treatment in later part of growth. The F$_2$ population shows continuous variation due to environmental effects and due to other minor gene effects. 14. The heritabilities for heading dates were ranged from 0.51 to 0.72, indicating that the selection in early generation might be effective. The extent of heritability for heading dates varied with environments; higher magnitude of heritability was obtained in short day treatment and high temperature compared with long day and low temperature treatments. The heritabilities of heading date due to response to short day were 0.86 in high temperature and 0.76 in low temperature. The heritabilities of heading date due to temperature were not significantly high. 15. The correlation coefficients of heading dates to the number of grains per spike, weight of 1, 000 grains. and grain yield were positive and high, indicating the difficulties of selections of high yielding lines from early population. But no significant correlation coefficient was obtained between the earliness and the number of spikes, indicating the effective selection for high tillering from early varieties for high yielding.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.169-171
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• 2000

전력선 통신망은 변압기 2차 측 저압 전력선을 이용하여 가전기기를 제어하는 홈 네트워크 구성과 수용가용 게이트웨이나 라우터 등을 통해 인터넷을 공유 할 수 있는 통신망이다. 최근 전력선을 이용한 Mbps급 고속 통신망이 개발되어 발표되었으며, 이와 관련한 국제 전시회나 포럼 등이 활발히 열리고 있다. 이에 본 논문에서는 서론에 전력선 통신망의 필요성과 개발과정을 간략히 서술하고, 본론에서는 전력선 통신망의 기본원리, 구성요소 및 프로토콜에 대하여 검토하였으며, 결론부분에서는 전력선 통신망의 개발에 있어서 기술적, 제도적 문제점과 향후전망에 대하여 기술하였다.

• Journal of electromagnetic engineering and science
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• v.15 no.4
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• pp.206-212
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• 2015

This paper introduces new wideband antenna-filter-antenna (AFA) uniform arrays that can be utilized as frequency selective surfaces (FSS) with low loss and sharp roll-off response, which are highly desirable characteristics for millimeter wave applications. The design adopts a simple 3-layer single polarization structure consisting of two patch antennas and a resonator. Both simulations and measurements are used to characterize the performances of the proposed design. Overall results show 18.5% 10-dB bandwidth. For the targeted band the insertion loss is less than 0.2 dB. Possible applications include quasi-optical amps, grid mixers and radomes for aircraft radar antennas.

• Proceedings of the KIEE Conference
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• 2002.07d
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• pp.2727-2729
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• 2002

In an emergency telemedicine system such as High-quality Multimedia based Real-time Emergency Telemedicine(HMRET) service, it is very important to examine the status of the patient continuously using the multimedia data including the biological signals(ECG, BP, Respiration, $SpO_2$) of the patient. In order to transmit these data real time through the communication means which have the limited transmission capacity. It is also necessary to compress the biological data besides other multimedia data. For the HMRET service, we developed the lossless biological signal compression program in MSVC++ 6.0 using DPCM method and JPEG Huffman table, and tested in an internet environment.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2959-2961
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• 2000

인터넷의 발전으로 기존의 가정 자동화의 개념이 변화되어 단순한 제어의 범위를 넘어 정보제공, 원격관리 등의 서비스와 연계되어 통합적인 흠 네트워크의 구축이 요구되고 있다. 이에 관련하여 기존에 포설된 망을 이용하여 흠 네트워크를 구축하는 방안으로 최근 들어 전력선을 이용한 통신 시스템 개발에 대한 관심이 고조되고 있다. 지금까지는 변압기 2차측에 설치되는 라우터나 전력신호와 통신 신호를 커플링하는 커플러 개발 등의 하드웨어에 대한 연구와 흠 네트워크 관리를 위한 웹브라우저의 개발에 대한 연구가 진행되어 왔다. 그러나 실제 흠 네트워크 제어를 위한 운영체제에 대한 연구는 미흡한 실정이다. 따라서 본 논문에서는 전력선 통신망 이용환경 하에서의 가전 네트워크 및 인터넷을 포괄하여 관리할 수 있는 전용 운영체제의 구성과 흠 네트워크를 위한 전력선 네트워크 어댑터의 기본 구조를 고찰 하였다.

• Journal of Electrical Engineering and Technology
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• v.12 no.3
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• pp.1124-1136
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• 2017

Direct Power Control technique has become popular in the grid connected Voltage Source Converter (VSC) applications due to its simplicity, direct voltage vector selection and improved dynamic performance. In this paper, a direct method to determine the effect of voltage vector on the instantaneous active and reactive power variations is developed. An alternative Look Up Table is proposed which minimizes the commutations in the converter and results in minimum reactive power variation. The application of suggested table is established for Shunt Active Power Filter (SAPF) application. The Predictive Direct Power Control method, which minimizes apparent power variation, is further investigated to reduce commutations in converters. Both the methods are validated using 2 kVA laboratory prototype of Shunt Active Power Filters (SAPF).

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.2
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• pp.673-694
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• 2021

In this paper, we intend to study the energy efficiency (EE) optimization for a simultaneous wireless information and power transfer (SWIPT)-based distributed antenna system (DAS). Firstly, a DAS-SWIPT model is formulated, whose goal is to maximize the EE of the system. Next, we propose an optimal resource allocation method by means of the Karush-Kuhn-Tucker condition as well as an ergodic method. Considering the complexity of the ergodic method, a suboptimal scheme with lower complexity is proposed by using an antenna selection scheme. Numerical results illustrate that our suboptimal method is able to achieve satisfactory performance of EE similar to an optimal one while reducing the calculation complexity.

• Journal of the Korean earth science society
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• v.32 no.4
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• pp.373-387
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• 2011

In this study, four types of sensitivity experiments (EG, EE, NG, NE; E: ERA-Interim, N: NCEP/DOE2, G: Grell scheme, E: Emanuel scheme) were performed to evaluate the simulation skills of RegCM4 released in July 2010 over the CORDEX (COordinated Regional Downscaling EXperiment) East Asia domain based on the combinations of boundary conditions (BC: ERA-Interim, NCEP/DOE2) and the cumulus parameterization schemes (CPS: Grell, Emanuel) for the 1989. The surface air temperature and precipitation data observed by the Korea Meteorological Adminstration were used to validate the simulation results over South Korea. The RegCM4 well simulates the seasonal and spatial variations of temperature but it fails to capture the seasonal and spatial variations of precipitation without consideration of the BC and CPS. Especially the simulated summer precipitation amount is significantly less in EG, NG, and NE experiments. But the seasonal variation of precipitation including summer precipitation is relatively well simulated in the EE experiment. The EE experiment shows a better skill in the seasonal march of East Asia summer monsoon, distribution of precipitation intensity and frequency than other experiments. In general, the skills of RegCM4 for temperature and precipitation are better during winter than summer, and in Emanuel than Grell schemes. The simulation results are more impacted by cumulus parameterization schemes than boundary conditions.