• Journal of the Korean Ceramic Society
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• v.30 no.6
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• pp.478-484
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• 1993

The influence of reaction conditions on the MnZn ferrite coprecipitation process were investigated using mixed metla sulfate solution and ammonium oxalate. In order to minimize the metallic ion losses and to control the particle size, the optimum reaction conditions were as follows; reaction temperature $25^{\circ}C$, metal sulfate concentration 0.3M, molar ratio of ammonium oxalate/mixed metal sulfate 1.1:1. The production yield was as high as 97.6% of theoretical yield at optimum reaction condition.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.3
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• pp.214-220
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• 1999

Rice production in Korea has markedly increased during the last two decades due to newly developed high yielding varieties and improved production technology. This experiment was conducted to determine the potential of tropical japonica germplasm in enhancing the yield of temperate japonica. The yield performance of two tropical japonicas (IR 65597-29-3-2 and IR66154-52-1-2) and one temperate japonica (Dongjinbyeo) was compared at different plant densities and nitrogen levels under Korean environmental conditions. Although tropical japonicas showed low tillering habit and large panicles, they had similar leaf area index and dry weight at heading stage to Dongjinbyeo of the high tillering type indicating that there was not much difference between tropical and temperate japonica in terms of biomass production. The highest milled rice yield of 6.15 t/ha was obtained from Dongjinbyeo at a high nitrogen level with less planting density (220 kg N/ha and 30 $\times$ 15 cm). However, those of the two tropical japonicas were 5.36 t/ha at the condition of 165 kg N/ha and 30 x 10 cm planting density and 5.06 t/ha at the condition of 165kgN/ha and 15 x 15 cm planting density, respectively. Ripened grain of tropical japonicas ranged from 65 to 87%, while that Dongjinbyeo ranged from 82 to 97% under Korean conditions.

• Journal of Microbiology and Biotechnology
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• v.25 no.11
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• pp.1920-1927
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• 2015

This study aimed to optimize four factors affecting biomass accumulation and 5-aminolevulinic acid (ALA) yield together with pollutants removal in Rhodobacter sphaeroides wastewater treatment. Results showed that it was feasible to produce biomass and ALA in R. sphaeroides wastewater treatment. Microaerobic, 1,000-3,000 lux, and pH 7.0 were optimal conditions for the highest ALA yield of 4.5 ± 0.5 mg/g-biomass. Under these conditions, COD removal and biomass production rate were 93.3 ± 0.9% and 31.8 ± 0.5 mg/l/h, respectively. In addition, trace elements Fe²⁺, Mg²⁺, Ni²⁺, and Zn²⁺ further improved the ALA yield, COD removal, and biomass production rate. Specifically, the highest ALA yield (12.5 ± 0.6 mg/g-biomass) was achieved with Fe²⁺ addition.

• ETRI Journal
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• v.33 no.6
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• pp.904-913
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• 2011

Three-dimensional (3D) memories using through-silicon vias (TSVs) as vertical buses across memory layers will likely be the first commercial application of 3D integrated circuit technology. The memory dies to stack together in a 3D memory are selected by a die-selection method. The conventional die-selection methods do not result in a high-enough yields of 3D memories because 3D memories are typically composed of known-good-dies (KGDs), which are repaired using self-contained redundancies. In 3D memory, redundancy sharing between neighboring vertical memory dies using TSVs is an effective strategy for yield enhancement. With the redundancy sharing strategy, a known-bad-die (KBD) possibly becomes a KGD after bonding. In this paper, we propose a novel die-selection method using KBDs as well as KGDs for yield enhancement in 3D memory. The proposed die-selection method uses three search-space conditions, which can reduce the search space for selecting memory dies to manufacture 3D memories. Simulation results show that the proposed die-selection method can significantly improve the yield of 3D memories in various fault distributions.

• The Korean Journal of Mycology
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• v.50 no.3
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• pp.161-171
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• 2022

The edible paddy straw mushroom Volvariella volvacea (Bull. ex F.) Singer has high nutritional and medicinal values. They are grown on a wide variety of agricultural by-products using different several methods. The result of this present study showed that type of bed and cultivation condition (outdoor/indoor) had effects on the yield of paddy straw mushrooms grown on the spent oyster mushroom sawdust. The treatment of circular compact bed under indoor cultivation condition (CYIC) had the best yield and biological efficiency (B.E.) with 2,119.2 g/bed and 14.5%, respectively, followed by the treatment of conventional bed under outdoor cultivation condition (COOC) with the yield and B.E. of 1,935.5 g/bed and 13.2%, respectively, but the lowest yield and B.E. were observed in the treatment of conventional bed under indoor cultivation condition (COIC) with 1,226.1 g/bed and 8.4%, respectively. Paddy straw mushrooms cultivated on spent oyster mushroom sawdust should be proper in both outdoor and indoor conditions by conventional and circular compact methods as well. However, in indoor conditions, paddy straw mushrooms should be grown in a circular compact bed to ensure the temperature of the bed is suitable for the mushroom growth.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.353-353
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• 2017

Rice yield of South Korea in 2015 was the highest of the last 30 years. It is important issue to establish food policy whether the historically highest yield in 2015 can be continued or just one-off event. Therefore, it is necessary to understand whether such a high yield as 2015 will be reoccurred. The aim of this study was to find out what climatic factor affect rice yield and how often these climatic factor could occur. For this study, the yield monitoring data from National Institute of Crop Science, Rural Development Administration and the meteorological data provided by Korea Meteorological Administration are used to identify the weather conditions could cause high yield, and how often these conditions occurred in the past. Our results indicated that such as high yield as 2015 could occur only when the mean sunshine hours of July and the mean sunshine hours from the end of August to early September was more than 5.1 hours and 6 hours, respectively. Mean sunshine hour of July may be related to grain number. The mean sunshine hour from the end of August to early September was presumed to relate to grain filling ratio. The relationship between monthly mean temperature and yield or yield component was not clear in this study. In this study, any cycle of high weather condition was not found. Therefore, the probability of high yield weather condition was expressed by frequency. The frequency of the sunshine hour, could make high yield, were 8/35 (23%) over the past 35 years. And the frequency of two years consecutive sunshine hour condition, which could cause high yield, was 1/35 (2.9%). The frequency of recurrence of sunshine hour making high yield within the next 5 years or 10 years after high yield weather condition were 4/35 (11.4%). After all, the high yield as much as yield of 2015 could not be one-off event. But it was not also consecutive event.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.8
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• pp.1200-1204
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• 1999

Two experiments were conducted to study the effect of urea treatment of rice and wheat straw on feed intake, dry matter (DM) digestibility and milk yield of lactation buffaloes in their late lactation under farmers' management conditions in the western hills of Nepal during 1995 and 1997. Dry matter intake (DMI) from urea treated rice and wheat straw was not improved significantly (p<0.05) nor the total DMI of the lactating buffaloes was improved significantly. However, feeding urea treated rice straw increased straw DMI by 14.2% and total DMI by 10.63% units over the untreated rice straw. Similarly, the increase in straw and total DMI were 20.18 and 17.40% units over the untreated wheat straw fed animals. Although there was no significant effect of urea treatment of both straw on DM digestibility, it was higher for treated than untreated straw at all locations. An overall increment of 18.1% units for rice straw and 13.3% units for wheat straw was observed. There was a significant effect (p<0.01) of feeding urea treated rice and wheat straw on the milk yield of lactating buffaloes during late lactation under farmers conditions. Post experiment milk yield was also significantly (p<0.05) higher for the animals fed treated straw in both the experiments. Buffalo milk yield was also significantly affected by breed (p<0.01), location (p<0.01) and parity (p<0.01) of the animals. General response of the farmers about the technology and their observed effect on animal performance was also very positive.

• Journal of the Korean Wood Science and Technology
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• v.43 no.5
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• pp.600-612
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• 2015

We investigated the optimization of the organosolv pretreatment of yellow poplar for bioethanol production. Response surface methodology was used to determine the optimal conditions of three independent variables (reaction temperature, reaction time, and sulfuric acid (SA) concentration). Reaction temperature is the most significant variable in the degradation of xylan and lignin in the presence of an acid catalyst, and ethanol production increased with a decrease in the lignin content. The highest ethanol concentration ($42.80g/{\ell}$) and theoretical ethanol yield (98.76%) were obtained at $152^{\circ}C$ (2.5 bar) with 1.6% SA for 16 min. However, because of excessive degradation of the raw material, the overall ethanol yield was less than under other pretreatment conditions which has approximately 50% of WIS recovery rate after pretreatment. The optimal conditions for the maximum overall ethanol yield ($146^{\circ}C$ with 1.22% SA for 15.9 min) were determined with a predicted yield of 17.11%, and the experimental values were very close (17.15%). Therefore, the quadratic model is reliable.

• Korean Journal of Plant Resources
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• v.26 no.5
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• pp.636-644
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• 2013

We examined the effects of soaking, saturation, and aging conditions of raw cowpea seeds, on the yield and growth responses of cowpea sprouts. The absorption caused rapid growth for the first two hours of soaking, then the growth slowed. The longer the soaking period (varied from 1 to 6 hours), the lower the germinability, yield ratio, and lateral root output became. A five-day saturation (moist $96{\pm}1%$, $20^{\circ}C$) treatment led to higher germinability, yield ratio, and lateral root output than no treatment and one- or three-day saturation treatment. High-temperature aging treatment led to lower germinability and yield ratio compared to no such treatment. Taking these findings into account, the optimal treatment conditions of raw cowpea seeds are a five-day saturation (moist $96{\pm}1%$, $20^{\circ}C$) treatment followed by cleaning and growing.

• YAKHAK HOEJI
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• v.42 no.2
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• pp.153-158
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• 1998

Calcium hydrogen phosphate was synthesized by reacting calcium chloride and sodium hydrogen phosphate solution in this study. It is well known that the particle size and yield o f calcium hydrogen phosphate produced is greatly affected by the synthetic conditions such as the reactant concentration, reaction temperature, reacting fine, mole ratio and drying temperature, etc. The purpose of this study is to investigate the optimum synthesis condition from the viewpoint of yield and sedimentation volume of the prepared calcium hydrogen phosphate powder according to a randomized complete block design proposed by G.E.P. Box and K.B. Wilson. It was found that the optimum synthetic conditions of calcium hydrogen phosphate were as follows: It was found that optirnum temperature range of reactant solutions was $28-38^{\circ}C$ and $32-42^{\circ}C$ respectively, on the viewpoint of yield and sedimentation volume. The optimum concentration range of reactant solutions was 5.5-10.0% and 6.9-7.4% respectively, on the viewpoint of yield and sedimentation volume. The optimum mole ratio of $CaCl_2$ to $Na_2HPO_4$ was in the range of 1.2-2.0 and the optimum reacting time range was 8.5-11.0 minutes. The optimum drying temperature range was $39-41^{\circ}C$ from the viewpoint of yield, but it was $39-43^{\circ}C$ on the basis of sedimentation volume. Crystallographic analysis to X-ray diffraction patterns of commercially available ecalcium hydrogen phosphate and calcium hydrogen phosphate samples prepared in this study suggested that all samples tested belonged to monoclinic crystal system characteristic of $CaHP0_4{\cdot}2H_20$ crystals.