• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.5
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• pp.813-817
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• 1987

High value sheet resistance (Rs' 1K-33K\ulcorner/) polysilicon resistors were fabricated using double ion implantation with boron as the major dopant and phosphorus compensation. It is observed that Rs sensitivity to the net doping concentration is decreased by one order of magnitude compared to the conventional (boron implanted)polysilicon resistors. The temperature co-efficient of resistance (TCR) measured between 25\ulcorner and 125\ulcorner shows equivalent values to those of non-compensated resistors for the same Rs. A qualitative electrical conductiion mechanism for compensated polysilicon resistor is proposed, based on the existing grain boundary charge trapping theory.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.231-233
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• 2003

Agricultural land use generally shows specific temporal characteristics of NDVI obtained from satellite data. In terms of winter wheat, a higher value compared with other land use types in May and a considerably low value in June could be discriminative features of temporal change of NDVI. In this study, the author examined methods for estimating winter wheat sown area in sub-pixel level of coarse resolution satellite data using temporal characteristics of NDVI. Application of the methods to the major grain production area in China exhibited properly a spatial distribution pattern of winter wheat sown area.

• Magazine of the Korean Society of Agricultural Engineers
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• v.16 no.4
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• pp.3600-3610
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• 1974

Experimental work of batch-type dryer was conducted to develop its optimurm operating conditions by analyzing the major factors which affect the drying performance. A laboratory batch-type dryer was constructed and tested for various levels of heated-air rates, and depths of grain deposit. Tong-il rice variety having the initial moisture content of approximaely 23 per cent in wet basis was used for the experiment. The criteria selected for establishing the optimum operating condition were the drying performance rate, the thermal efficiency, and the operational cost of the dryer. The results of the study are summarized as follows: 1. The performance rate of dryer for a specific operating condition was defined as total amount of material dried per hour when the moisture content of grains in the upperlayer reaches to 16 per cent in wet basis. The optimum operating conditions as viewed in the rate of drying performance could be justified by functional realtionship between the depth of grain deposit and air flow rate. In other words, there was a definite depth of grain deposit for a given air-rate which make the dryer performance maximum. The optimum grain depth for the batch-type dryer with 3.3㎡ loading area and with the attached axial fan was about 35cm. 2. The thermal efficiency for the dryer was evaluated by the ratio of the latent heat required to evaporate the grain moisture to the heat input required to raise the ambient air-temperature to 40 degree centigrade. The optimum operating condition as viewed in term of thermal efficiency analyzed was that grater depth and lower air flow-rate may be desirable. This condition is contracted with the optimum condition as viewed by the dryer performance rate. 3. The annual operating cost of batch-type dryer was analyzed for different annual hour of use and for different operation condition. The optimum condition as viewed in terms of operating cost was almost identical to one as viewed in terms of dryer performance rate. Therefore, the most economical use of batch-type dryer for the same annual operating hours can be obtained when the dryer operated in the condition of maximum dryer performance rate. Increasing the annual operating hour may be desirable to cut down the dryer operation cost, since the annual hour of dryer use is much sensitive to the operating cost than any peractical conditions of dryer operation. 4. The most desirable operational condition as justified by combining all the criteria, dryer performance rate, thermal efficiency and annual operating cost, could be concluded to operate the dryer in the condition of maximum performance rate. The condition in general is identical to the lowest operation cost for a given annual operating hour.

• Korean Journal of Agricultural Science
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• v.35 no.1
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• pp.101-118
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• 2008

This paper reviews the present situation of Triticale cultivation and examines the potentiality of contribution to livestock as well as poultry sector in Bangladesh Agriculture. Triticale is a human-made cross between rye and durum wheat that has the ability to produce quality green fodder, and then re-grow after first and second cutting to produce grain. In Bangladesh, it is a non-traditional cereal that grows well during the cool and dry Rabi season (November-March) when fodder and feed scarcity is a major limiting factor for ruminant livestock. In Bangladesh Triticale was started to grow in the late Ninety's. The scientists of Bangladesh Agricultural Research Institute (BARI) were first introduced triticale in Bangladesh. Still now the situation of Triticale is grown as fooder and feed in Bangladesh within the scientists under trial. High quality grass fodder was obtained by cutting green triticale plants twice, at 35 and 50 days after seeding, while later the ratooning tillers produced grain to a yield of 1.1-2.4 t/ha of grain for poultry feed or human food. Triticale straw was twice as nutritious as rice or wheat straw and its grain contained more protein than other cereals. Researchers and farmers have also successfully made triticale hay and silage from a mixture of triticale green cuttings, rice straw and molasses. A feeding trial at Bangladesh Livestock Research Institute(BLRI), Savar station showed a large(46%) increase in cow live weight gain and a 36% increase in milk yield (but no change in milk quality or dry matter intake) in cows fed triticale silage compared with those fed rice straw over a period of nine weeks. In another feeding trial, it was found that triticale grain was a good replacement for wheat in the feed blend for chickens in Bangladesh. So it will be a good chance to alive our livestock as well as poultry sector if triticale enters to our existing cropping system as fodder cum grain. The challenge in Bangladesh is to identify fodder technologies that match existing small-scale farmer cropping patterns without needing major inputs or increasing risks. Preliminary field experiments revealed that triticale is a crop with good potential to produce quality fodder and grain for small scale farmers in Bangladesh.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.67 no.4
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• pp.234-241
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• 2022

Wheat (Triticum aestivum L.) is a major staple foods and is in increasing demand in the world. The elevated temperature caused by changes in climate and environmental conditions is a major factor affecting wheat development and grain quality. The optimal temperature range for winter wheat is between 15 and 25℃, and it is necessary to study the physiological characteristic of wheat according to elevated temperatures. This study presents the effect of elevated temperature on the yield and quality of two Korean bread wheat (Baekkang and Jokyoung) in temperature gradient tunnels (TGT). Two bread wheat cultivars were grown in TGT at four different temperature conditions: T0 (control, near ambient temperature), T1 (T0+1℃), T2 (T0+2℃), (T0+2℃), T3 (T0+3℃). The period from sowing to heading stage accelerated and the number of grains per spike and grain yield reduced under T3 condition compared with those under T0 condition. Grain filling rate and grain maturity also accelerated with elevated temperature (T3). The increase in temperature led to the increase in protein contents, whereas decreased the total starch contents. These results are consistent with the decreased expression of starch synthesis genes and increased gliadin synthesis or gluten metabolism genes during the late grain filling stage. Taken together, our results suggest that the increase in temperature (T3) led to the decrease in grain yield by regulating the number of grains/spike, whereas increased the protein content by regulating the expression of starch and gliadin-related genes or gluten metabolism process genes expression. In addition, our results provide a useful physiological information on the response of wheat to heat stress.

• Progress in Superconductivity
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• v.1 no.1
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• pp.56-60
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• 1999

Ultra fine MgO particles added BSCCO tapes were fabricated by tape casting using Doctor Blade Method and enclosed by silver foil for different starting compositions (that is, 2223 major, 2212 major). In order to obtain optimum microstructure, thermomechanical treatment was done. Microstructure and phase were analyzed by XRD, SEM and DTA. The critical current density was measured under magnetic field at 77K. The tapes fabricated from the precursor powder with BSCCO-2223 phase (>90%) result in a microstructure with a larger grain size and higher transport critical current density value under magnetic field at given thermomechanical treatment conditions.

• Nutritional Sciences
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• v.2 no.2
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• pp.82-87
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• 1999

Zinc nutriture in South Koreans was evaluated by estimating Zn, Ca, and phytate intake, and the molar ratios of phytate : Zn and the millimolar ratios of phytate $\times$ Ca Zn. food consumption data from the 95 National Nutrition Survey was used. For the present study, data from the nationwide, large city and urban area level were used. No standard deviation measures were provided in the 95 National Nutrition Survey : only mean values were reported. Nationwide daily intake of Zn and Ca were 10.1 mg/day and 426.5 mg/day, respectively. The estimated daily phytate intake was 1676.6 mg/day nationwide. The molar ratio of phvtate : Zn, the millimolar ratio of phytate $\times$ Ca : Zn and the phytate $\times$ Ca Zn mmol per 4.2 MJ (1000 kcal) were 15.9, 168.9 and 91.8 in nationwide, respectively. The major food groups for zinc intake were meat, poultry products (43%), and cereals and grain products (18%). Sixty two percent of Zinc was from animal food sources. Cereal and grain products supplied most of the phytate intake (46%), followed by seasonings, fruits, and legume products. The major food source of phytate was rice (39%) . The results of the present study suggest that Zn status of Koreans maybe influenced by high dietary intake of phytate and high molar ratios of phytate : Zn and phytate $\times$ Ca : Zn. These results raise concerns about Zn status of Koreans, who consume a diet higher in phytate than Western diets. further research is necessary to confirm whether such poorly available dietary Zn has any impact on the health of Koreans.

• Journal of the Korean Geographical Society
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• v.46 no.1
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• pp.1-19
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• 2011

The physical and chemical characteristics of loess-paleosol sequence in Jeongjang-ri, Geochang basin are examined using the magnetic susceptibility measurement, grain size analysis, OSL age dating, major, rare earth and trace elements analysis. The grain size characteristics of the loess-palesol sequence are obviously different from those of river sediment forming river terrace deposits and the Chinese Loess Plateau. The loess-paleosol sequence consisting of L1, L1LL1, L1S1, L1L2, S1 and L2 from top to bottom is estimated to MIS 2~MIS 6 and the river terrace to MIS 7. The compositions of major, rare earth and trace elements indicate that the sequence show more weathered characteristics than the Chinese Loess Plateau and originated from the Chinese Loess Plateau. These features are in harmony with the previous studies in Korea.

• Korean Journal of Ecology and Environment
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• v.48 no.3
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• pp.168-175
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• 2015

This study was conducted in autumn to determine phosphorus (P) fraction in sediments of Daechung Lake, to elucidate controlling factors for sedimentary P, and to compare with the other areas. For this study, sediment samples were collected at 6 sites only once on November 2014 using ponar grab and analyzed for solid-phase P (Loosely adsorbed, Fe-bound, Al-bound, detrital apatite, and refractory organic P) by sequential extraction. Total phosphorus (TP) was relatively high in front of Daechung Dam and Hoinam where fish farm was run until 1997. The dominant sedimentary P form was Al-bound P, followed by Fe-bound P, which could be released from sediment to water column during suboxic state. Based on principal component analysis, Al-bound P, Fe-bound, and TP were controlled by grain size of sediments. Loosely adsorbed, detrital apatite, and refractory organic P were relatively highly accumulated at the mouth of major tributaries where suspended sediments were delivered. Sedimentary P concentrations in Daechung Lake sediments were not higher than in other lake sediments. Therefore, based on these results, major controlling factors were grain size and input of suspended sediments from tributaries.

• Korean Journal of Agricultural Science
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• v.47 no.4
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• pp.717-726
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• 2020

The physical characteristics of the major varieties of perilla were analyzed to use as basic data for the design of a high-quality, high-efficiency perilla cleaner and stone separator. Because the size, thousand-grain weight, angle of repose, angle of friction, bulk density and terminal velocity of perilla have significant differences according to the perilla variety, the different of characteristics by variety should be considered for performance improvement of a perilla cleaner and stone separator. Therefore the cleaner and stone separator using a sieve could be improved by the application of a detachable sieve or by using equipment such as a 2 - 3 stage sieve and regulating the slope. Moreover, because differences in the terminal velocity occur due to the differences in the size and thousand-grain weight according to the perilla variety, a blower with an adjustable fan speed was considered for the design of the improved cleaner. Additionally, it was shown that the length of perilla has the greatest correlation based on a comparison of the coefficients of the other characteristics. Accordingly, the length of perilla could be used as a major factor for the fine adjustment and parts replacement of the device. These results can be used as basic data for a high-quality, high-efficiency perilla cleaner and stone separator. In the future, the development of the machine and follow-up studies based on the basic data are needed to determine the optimized operating conditions and mechanism of action.