• 한국작물학회지
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• 제44권2호
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• pp.143-148
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• 1999

Soil moisture condition is an important limiting factor in growth and yield in rice culture. The purpose of this study was to compare the influence on the growth, yield and Quality of rice subjected to soil moisture stress (SMS) at different growth stages. Ajaponica rice cultivar, Dongjinbyeo, was cultured under flooded conditions in a plastic container filled with silty loam soil. The container was subjected to SMS until the initial wilting point (IWP) coincided with about 10% in soil moisture content and about-200 kPa in soil matric potential, and was then irrigated again, at 6 and 5 of main growth stage in 1996 and 1997, respectively. At maturity, the plant height, tiller number, leaf area and top dry weight were decreased more in SMS treatments at the early stage than the late stage. The averaged yield index of SMS to control in both years was lowest at meiosis (62.5%), which primarily resulted from lower percent ripened grain and 1,000 grain weight, and second＇ reduced the spikelet number per panicle and panicle number per hill, and followed at tillering stage (68.5%) which resulted from the lower production in tiller number and top dry matter during and after SMS treatment. The percent-age of read rice in SMS plants varied with the treatment stage as order of lower at meiosis (44.0%), heading (53.9%), panicle initiation (70.1%), tillering (72.1%), ripening (75.8%) and 5 days after transplanting (DAT) (79.0%). Protein content in brown rice was slightly larger in SMS at late growth stage than the control, while the contents of fat and ash differed very little between SMS and control. Contents of Mg and K and Mg/K in brown rice with SMS were lower at some treatment stages such as at ripening or panicle initiation.

• 한국작물학회지
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• 제53권1호
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• pp.58-63
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• 2008

1. 수확시기에 따른 도정수율은 메벼의 적기수확시기보다 5일정도 늦게 수확하는 것이 높았으며 품종에 따라서는 보석찰벼와 해평찰벼가 도정수율이 높았다. 2. 찹쌀의 특징인 불투명한 유백색은 수분함량 14.0%이상부터 점차 소실되기 시작하여 15.0%대에 마치 멥쌀이 섞인 것처럼 보이다가 16.0%이상에 도달될 경우는 거의 대부분이 멥쌀과 같은 외관을 나타냈다. 3. 수분 증가에 따른 찹쌀의 유백색 소실은 조기에 수확된 벼에서 더 민감하게 나타나기 때문에 가능한 수확시기를 적기 이후로 정하는 것이 건조효율이나 찹쌀 수율 측면에서 더 유리하다고 판단된다. 4. 찹쌀 고유의 유백색 발현을 최대로 하기 위해서는 찰벼 건조수분의 critical point은 13.5%이하였다.

• 농업과학연구
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• 제7권2호
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• pp.145-155
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• 1980

곡물(穀物)의 초기온도(初期溫度), 함수율(含水率), 공극률(空隙率)을 변화(變化)시키면서 미맥(米麥)의 비열(比熱)을 Cooling curve method에 의(依)해 측정(測定)하여 이들 세 인자(因子)를 함수(函數)로 하는 미맥(米麥)의 비열(比熱)에 관(關)한 수학적(數學的) 모델을 개발(開發)하였으며 이들 인자(因子)들이 비열(比熱)에 미치는 영향(影響)을 분석(分析)했던 바 그 결과(結果)를 요약(要約)하면 다음과 같다. 1. 공시(供試)된 미맥(米麥)의 비열(比熱) 변화(變化) 범위(範圍)는 과맥의 경우 $1.8209-2.7041kJ/kg\;^{\circ}K$, 대맥(大麥) $1.8862-2.5625kJ/kg\;^{\circ}K$, Japonica형(型)벼 $1.5167-2.3779kJ/kg\;^{\circ}K$, 통일형(統一型)벼 $1.5260-2.3981kJ/kg\;^{\circ}K$였다. 2. 곡물(穀物)의 초기온도(初期溫度), 함수율(含水率), 공극률(空隙率) 등(等)을 함수(含水)로 하는 미맥(米麥) 비열(比熱)을 모델을 각(各) 공시곡물(供試穀物) 별(別)로 개발(開發)하였으며 벼의 경우 Japonica형(型)벼와 통일형(統一型)벼의 모델을 따로 유도(誘導)하였다. 3. 곡물(穀物)의 초기온도(初期溫度)에 따른 비열(比熱)의 변화(變化)는 벼의 경우 초기온도(初期溫度)에 따라 감소(減少)하였으나 보리의 경우는 초기온도(初期溫度)에 따라 증가(增加)하였다. 4. 미맥(米麥)의 비열(比熱)은 그 함수율(含水率)이 증가(增加)함에 따라 대체(大體)로 증가(增加)하였다. 5. 공극률(空隙率)에 따른 비열(比熱)의 변화(變化)는 통일형(統一型) 벼를 제외(除外)한 모든 공시곡물(供試穀物)에서 공극률(空隙率)에 따라 비열(比熱)은 감소(減少)하였다.

• Journal of Biosystems Engineering
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• 제30권3호
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• pp.155-160
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• 2005

The objective of this research was to establish a domestically available cooling storage technique by cold-air in winter, using winter cool air ventilation fur determining rough rice cooling method in the storage and dry bin. The rough rice storage characteristics of two test conditions, winter cool-air ventilation storage and ambient temperature storage, were evaluated from January to July 2001, using a storage and dry bin of 300-ton capacity. Results of this research are as follows: Grain temperature was from $-5.1\~-8.5^{\circ}C$ after winter cool-air ventilation, and grain initial temperature for ambient temperature bin storage was $0.3\~1.9^{\circ}C$. Moisture content of rough rice decreased from $0.28\;to\;0.93\%$ and from $1.53\;to\;1.92\%$ to compare with original moisture contents for winter cool-air ventilation, and for ambient temperature bin storage, respectively. Broken ratio of brown rice from winter cool-air ventilation bin increased from $0.16\;to\; 0.92\%$, and brown rice broken ratio was from $2.24\;to\;2.86\%$ for ambient temperature bin storage to compare with initial broken ratio. Hardness of stored rice increased along storage period increase in alt storage methods, and cooling bin storage increased rice hardness of 0.271kgf: this increasing was lower then the other methods from 0.059 to 2.239kgf. Germination rates were decreased approximately 9.03, 3.14 and $3.20\%$ for upper, middle, and bottom of ventilating winter air bin, respectively, and germination rates of 2.70, 3.47 and $4.14\%$ were approximately decreased for upper, middle, and bottom parts of ambient temperature bin storage, respectively.

• 한국초지조사료학회지
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• 제38권2호
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• pp.112-119
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• 2018

출수 후 수확일수에 따라 수량 및 사료가치를 고려해 보면 밀 수량은 출수 후 30일부터 42일까지 유의적으로 증가하였으며(p<0.05), 최대 수량은 42일차에 5.57T/ha이었는데, 39일, 42일차와는 유의적 차이를 보이지 않았다. 사료가치의 경우 조단백, 조섬유, 조회분의 경우 유의적 차이를 보이나, 조지방, TDN의 경우 유의적 차이를 보이지 않았다(p<0.05). 발효에 영향을 주는 pH는 30일부터 39일까지는 pH 3.8-4.2까지 안정을 유지하다가 42일차부터는 pH4.5로 증가하여 일부 품종의 경우 발효에 적합하지 않았다(p<0.05). 따라서 밀의 곡실 발효사료 제조를 위한 최적 수확시기는 출수 후 39일차였다.

• 미생물학회지
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• 제19권1호
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• pp.14-22
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• 1981

Protein content of cellulosic wastes, such as spent grain, hop bark, spent rye, rice straw, rice hull, saw dust and used newspaper, was increased by a mixed culture of C. utilis wastes having 66-75% moisture. Among the fungal strains tested. A.phoenicis KU175 was the most powerful to increase the protein content of A. phoenicis during the mixed culture with C. utilis in the CMC medium reached at the peak for one day culture after inoculation of the both strains at the same time, while it reached at peark from the beginning of the mixed culture, when A. phoenicis was inocultated for 12-24hours prior to the inoculation of C.utilis. To increase the protein content of the cellulosic wastes by the mixed culture of C.utilis and A.phoenicis, the inoculation of both strains at the same time was more effective than the preinoculation of A. phoenicis for 6-24 hours. Content of crude cellulose in the used newspaper, saw dust and spent grain was high relatively, and the lignin content of spent grain, spent rye, and rice strew was reduced more than half by the treatment of 2% NaOH. However, effect of alkali treatment of increase the protein content of the cellulosic wastes was not prominent in the case of mixed culture. Protein content of the cellulosic wastes was increased prominently by the mixed culture of C.utilis and A.phoenicis in semi-solid substrate, compared with the single culture of C. utilis, although the latter increased the protein content of cellulosic wastes considerably. The effect of mixed culture of C. utilis and A. phoenicis increased 4-fold the protein content of spent grain, and more than doubled crude protein in hop bark and rice straw.

• Journal of Biosystems Engineering
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• 제3권2호
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• pp.114-125
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• 1978

The use of petroleum fuels in grain drying causes problems of high cost and management. To solve these problems, it is required to study on soLar energy as an alternative to petroleum fuels for grain drying. The purposes of this study were to find out the optimum received area and air flow rate of a flat-plate solar air collector for grain drying and to assess its effects on grain drying with a small grain bin. The results of this study are summarized as follows ; 1. The calculated optimum tilt angles of the collector in the summer and autumn drying seasons were 20 and 50 degress, respectively, in suwon area. 2. The outlet temperature of the collector was $36^\circ C$ on the daily average with the maximum of $36^\circ C$ at 12:00 o clock. Solar radiation on the collector surface was 1.04 ly( 1 langley = 1 cal/$cm^2$) per minute on the daily average and 1.30 ly per minute on the maximum at 11:00am. The thermal efficiency of the collector was 62.4 percent on the daily average, and the air flow-rate per unit receiving are was 1.03 $m^3$/min/$m^2$.4. The calculated optimum receiving area and the air flow-rate per unit cubic volume for paddy in autumn drying season was 2 $m^2$ and 2$m^3$/min , respectively. 5. not significantly difference in the collector efficiency was appeared between the rotating and fixed type of solar collector. 6. For drying of wheat with 0.6 meter of the depth in the bin, approximately 9 hours were required to reduce the moisture content from 21.6% to 13% with air follow rate of 5 $m^3$/min an initial moisture per cubic meter of wheat and with air temperature of $52^\circ C$. 7. In the drying test of rough rice with a turning operation in a grain bin approximately 21 hours were required to reduced the moisture from 21% to 14.5% with airflow rate of 2 $m^3$/min per cubic meter of rice and the air temperature of $43.5^\circ C$. 8. Over-drying at the bottom and less -drying at the top of the grain mass was resulted from the high -temperature of drying air which was obtained from the flat-plate solar collector in this test. An appropriate operation should be prepared for the uniform moisture of the grain in the bin.

• 한국측량학회지
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• 제36권1호
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• pp.25-32
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• 2018

Namdae-cheon in Gangwon-do Province, Korea, is a valuable well-preserved lagoon. The estuary of Namdae-cheon Stream is closed because of the surrounding natural sand shoal. Thus, during the dry season, river water cannot easily flow to the ocean and therefore stagnates. River water congestion causes environmental deterioration of estuaries, often by eutrophication. In this study, we examined wall disintegration in the estuary area and used it to determine appropriate measures for the conservation of estuary water quality in the future. A total of 24 sites were selected, with 13 sites on the west side and 11 sites on the east side of the estuary study area. Samples were collected and analyzed for particle size and moisture content both vertically and horizontally. Sedimentary deposition rate was measured, and subsidence analysis was performed. Particle size, water content, sedimentary deposition, and subsidence analyses indicated that flow shifted to the west during the study period. In conjunction with other variables that may affect changes in flow, these parameters can be used in future research to predict shoal breaches and associated changes in water flow direction.

• 한국농공학회지
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• 제23권4호
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• pp.53-59
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• 1981

This experiment was carried out to find out the effectiveness of soil cement stabilization about the Song-I in Cheju province. The results are summarized as follows; 1.The increasing ratio of unconfined compressive strength according to the increment of cement content was markedly low compared with the weathered granite soil, so the effect of stabilization was low. 2.The moisture content of the sample of Song-I indicates the maximum unconfined compressive strength showed at the 5% or so of dry side than the optimum moisture content and the change of the unconfined compressive strength according to the change of moisture content was not sensitive compared with the weathered granite soil. 3.Generally the primary strength of curing age within 7 days of the sulfate resisting cement was low compared with the normal portland cement and the strength of 28 curing days showed a similar tendency, especially in case of Song-I, and it seemed that the sulfate resisting cement was a little more effective than the normal portland cement. 4.As the unconfined compressive strength of grain size controlled Song-I was low compared with the weathered granite soil, so the rate of weight loss by the durability test was great, therefore it was thought that the durability was weak.

• 한국식품조리과학회지
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• 제27권6호
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• pp.745-754
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• 2011

To improve the textural properties of gluten free rice flour based products, the physicochemical and pasting properties of extruded non-waxy rice flours using extruder were investigated. The high yielding Tongil type rice variety, Hanarum was used. Hanarum rice flour was prepared by dry milling from soaked and dried rice grain. The operation conditions of twin screw extruder were 250 rpm of screw speed, $160^{\circ}C$ of barrel temperature, and 24, 27, and 30% of moisture content. Hanarum extruded rice flour (HERF) were lower in crude lipid and ash contents, but higher in crude protein than Hanarum rice flour (HRF). The color values of HERF showed significantly different (p<0.05) with different moisture contents. Water binding capacities, apparent amylose contents, and damaged starch of HERF were higher than those of HRF. Moisture contents affected water binding capacities of HERF. Solubility increased with increasing heating temperature and solubilities of HERF differed significantly (p<0.05). X-ray crystallinity was changed after extrusion cooking and that of HERF showed sharp peaks at $2{\theta}=18-20^{\circ}$. The pasting viscosities of HERF kept lower values (~ 10 RVU) constantly.