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        검색결과 396

        281.
        2017.06 KCI 등재 서비스 종료(열람 제한)
        ‘Sinhwangok’, a new maize F1 hybrid (Zea mays L.), is developed by the maize breeding team at the National Institute of Crop Science (NICS), RDA in 2015. The high-yielding hybrid, named ‘Sinhwangok’ was bred by crossing between two inbred lines, ‘KS178’ and ‘KS145’. It is a yellow dent maize hybrid. After advanced yield trial of ‘Sinhwangok’ in Suwon for two years, regional yield trial was subsequently carried out for evaluation of its growth and yield at three different locations from 2012 to 2015. The days to silking of ‘Sinhwangok’ are 74. The plant height of ‘Sinhwangok’ is 241cm, similar to ‘Jangdaok’, and its ear height ratio is 51%, similar with that of ‘Jangdaok’. It has resistance to lodging. The number of ear per 100 plants is 96. The ear length of ‘Sinhwangok’ is 17cm, shorter than that of ‘Jangdaok’. The weight of 100 seeds of ‘Sinhwangok’ is 34.1g, similar to that of ‘Jangdaok’. It has moderate resistance to southern leaf blight (Bipolaris maydis). It has moderate resistance to European Corn Borer (Ostrinia nubilalis). The grain yield (8.9 ton/ha) of ‘Sinhwangok’ was 15% higher than that of ‘Jangdaok’. The seed production of ‘Sinhwangok’ was acceptable due to a good synchronization of flowering period during crossing between the seed parent, KS178, and the pollen parent, KS145, in Yeongwol and F1 seed yield was 2.3 ton/ha. ‘Sinhwangok’ would be a suitable cultivar to all plain area in Korea.
        282.
        2017.05 서비스 종료(열람 제한)
        산업활동으로 인한 대량생산, 대량소비, 대량폐기의 사회체계는 자원고갈, 지구온난화 등의 환경문제를 유발시켜 인류의 지속가능성을 위협하고 있다. 이러한 상황에서 자원순환형 사회체계 구축은 다양성, 자립성, 안전성, 순환성을 강조하는 지속가능성의 관점에서 인류의 생존을 위한 필수적인 방향으로 인식되고 있다. 자원순환형 경제 및 산업구조 구축을 위해서는 자원순환기술의 개발을 통한 폐기물의 자원화 실현이 수행되어야 한다. 한편 폐기물 자원화를 위한 재활용기술 역시 공정가동을 위해 사용되는 에너지 및 자원으로 인해 환경오염이 발생되고, 경제적인 측면에서 새로운 자원을 채취하는 것보다 많은 비용을 발생시킬 수 있다. 따라서 재활용재와 신재에 대한 전과정평가 수행을 통해 환경·경제적 가치를 분석하고 재활용 기술의 경쟁력 증진을 위한 개선안을 도출하는 것은 지속가능한 자원순환형 경제 및 산업구조 구축을 위해 매우 중요하다. 본 연구는 LCD, 반도체 등의 생산공정에서 발생하는 공정폐액에서 귀금속(금, 은)을 회수하는 재활용 기술을 대상으로 전과정평가를 수행하여 지구온난화, 자원소모, 산성화, 부영양화, 광화학적산화물생성의 5대 영향 범주에 대해 환경영향을 평가하였다. 공정폐액 1L 처리 시 지구온난화 영향은 5.26E-02 kg CO2 eq., 자원소모 영향은 3.06E-04 kg Sb eq., 산성화 영향은 1.31E-04 kg SO2 eq. 부영양화 영향은 9.70E-05 kg PO43- eq., 광화학적산화물생성 영향은 5.82E-05 kg C2H4 eq.로 도출되었다. 전과정평가 결과를 바탕으로 공정폐액 재활용 기술을 통해 회수되는 재생금의 환경・경제적 가치 분석을 수행하였다. 5대 영향범주에 대해 비용편익 분석기법에 기초하여 사회적 편익을 포함하는 영향범주 별 경제적 원단위를 적용하였다. 공정폐액을 재활용하여 회수되는 재생금 1kg을 기준으로 평가하였을 때 환경・경제적으로 31,481원의 이득을 취할 수 있으며, 공정 1cycle인 300,000L의 공정폐액을 처리할 경우 85.8kg의 재생금이 생산되므로 2,691,651원의 이득을 얻을 수 있다. 공정폐액 재활용 기술에 대한 전체 환경영향 범주에 있어 전기와 KCN으로 인한 기여도가 가장 크므로 에너지 효율을 위한 에너지원 변경 및 신재생에너지 적용 등의 방안 및 KCN을 대체 할 수 있는 물질에 대한 원단위 환경영향 비교가 필요하다. 또한, 금, 은에 대한 환경영향 회피효과가 매우 크고, 경제성 또한 확보되기 때문에 다양한 활용이 가능할 것으로 보인다.
        283.
        2017.03 KCI 등재 서비스 종료(열람 제한)
        Recently, domestic waste policy has focused on resource circulation. In accordance with Article 3, Paragraph 2 of the “Enforcement Rules of Wastes Control Act”, which is targeted at waste incineration facilities, we established and announced methods for calculating the recovery and utilization rates of incineration-sourced heat in 2015. The lower heating value is important to energy recovery and utilization rate calculations. Hence, the lower heating values of the waste incineration facilities were estimated using the thermal method from KS B 6205. Heat loss decreases the heat recovery efficiency, and should be measured and evaluated. The surface temperatures of the incinerator and boiler are required to determine heat loss. Presently, the contact point temperature method is used to measure the surface temperature. It is difficult to apply this method to the average surface temperature of an incineration facility. In this study, 20 Korean waste incineration facilities were selected for heat loss estimates based on waste incineration temperature, incinerator type, and incineration capacity. Infrared thermal cameras were used to measure the surface temperatures of the waste incineration facilities.
        284.
        2016.12 KCI 등재 서비스 종료(열람 제한)
        Various efforts have been made to increase use of renewable energy sources and reduce greenhouse gas emissions in Korea as economic and population growth have increased. Bio-energy is a renewable form of energy unlike fossil fuels and is not included in greenhouse gases because it is carbon neutral (sometimes referred to as “climate neutral”) and is exempted from total CO2 emissions. In this study, we determined the low heating value (kcal/kg) and elemental composition using the biogenic content of “wood” and a solid recovered fossil fuel “polyethylene product” to confirm the solid recovered fuel value. Biomass content was also determined using the selective dissolution method and 14C-method (AMS). Additionally, we developed a gas sampling system to collect gases emitted after combustion at 850oC to determine biomass content by AMS.
        285.
        2016.11 KCI 등재 서비스 종료(열람 제한)
        This paper proposes a design methodology of self-reconfigurable kinematics and control engine for modular and reconfigurable robots. A modular manipulator has been proposed to meet the requirement of task adaptation in versatile needs for service and industrial robot area and the function of self-reconfiguration is required to extend the application of modular robots. Kinematic and dynamic contexts are extracted from the module and assembly information and related codes are automatically generated including controller. Thus a user can easily build and use a modular robot without professional knowledge. Simulation results are presented to verify the validity of the proposed method.
        286.
        2016.10 KCI 등재 서비스 종료(열람 제한)
        Little attention has been paid to the functional aspect of the flower petal of Paeonia lactiflora, compared to that of its root. To determine the components of flower petal of Paeonia lactiflora, we conducted the Fourier transform ion cyclotron resonance (FT-ICR) MASS spectrophotometric analysis. We detected the 24 different types of ingredients from the 70% ethanol extracts of flower petal of peonia lactiflora cv. ‘Red Charm’. The main compounds were quercetin glucopyranosides, methyl gallate, paonioflolol and kaemperol glucopyranosides. We further tested its functional activity. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity of the extracts was 87.9-90.4% at 0.1mg/ml. This result showed that these flower extracts have approximately 5-fold stronger antioxidant potential than a previous report with root extracts (Bang et al. 1999). The result of tyrosinase inhibition assay of Paeonia lactflora extract was almost similar to that of arbutin except significantly higher effect in the coral sunset extract at 0.1% concentration. Hyaluronidase inhibition assay showed 76.5% inhibition at 5% concentration of this flower extract, indicating that Peaonia lactiflora flower extracts have the major anti-inflammatory, anti-oxidant and brightening effects. Taken together, these results suggest these three Paeonia lactiflora species extracts might provide the basis to develop a new natural brightening agent.
        287.
        2016.10 서비스 종료(열람 제한)
        Concrete with a pore solution of pH 10-12 is less alkaline than sound concrete but would still produce a strong color hange with phenolphthalein indicator. It therefore follows that the indicator test is likely to underestimate the depth to which carbonation has occurred. The indicator has not changed color near the top and bottom surfaces, suggesting that these near-surface regions are carbonated to a depth of at least 3 mm from the top surface and 5 mm from the lower surface. Where the indicator has turned purple - the center of the slab - the pH of the concrete pore fluid remains high (above 8.6, probably nearer 10).. Based on the above technical background, this study was devoted to examine the depth analysis of carbonated concrete quantitatively.
        288.
        2016.09 KCI 등재 서비스 종료(열람 제한)
        ‘Jungmo1038', a mid-late maturing, high dry matter yielding rice (Oryza sativa L.) cultivar with glabrous leaf and hull, was developed for whole crop silage (WCS) use. It was derived from a cross between ‘SR24592-HB2319’ with high biomass, smooth leaf and hull and good germinability in low temperature and new plant type (NPT), ‘IR73165-B-6-1-1‘ which had low tillering trait, large panicle, dark green leaf, thick and sturdy stem and vigorous root system. This cultivar had about 125 days growth period from seeding to heading, 99㎝ culm length, 20㎝ panicle length, 13 panicles per hill, 119 spikelets per panicle and 1,000-grain weight of 23.3 g as brown rice in central plain region, Suwon. This hairless WCS rice variety was weak to cold stresses similar to ‘Nokyang’ but was resistant to lodging in the field, strong to viviparous germination and good to low temperature germination. In addition, ‘Jungmo1038’ was resistant to leaf and neck blast but susceptible to bacterial blight, rice stripe virus and brown planthopper. Its average dry matter yield for three years reached 17.2 MT/ha, 21% higher than that of ‘Nokyang’. This glabrous cultivar had 6.6% crude protein and 62.4% total digestible nutrients a little low compared to ‘Nokyang’. In Korea peninsular, 'Jungmo1038' grows well in central and southern plain and is good to harvest between 15 to 30 days after heading to improve its feeding value and digestion rate of livestock(Grant No. 5634).
        289.
        2016.06 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        본 연구는 꽃송이버섯 원물과 꽃송이버섯 8% 첨가하여 유산균으로 발효한 꽃송이버섯 혼합물의 이화학적 특성 및 항산화 활성을 비교 조사하였다. 유산균 발효 꽃송이버 섯 혼합물의 수분, 조지방 및 조회분 함량은 버섯 원물에 비해 유의적으로 높게 나타났다(p<0.05). 꽃송이버섯원물 과 유산균 발효 꽃송이버섯 혼합물의 총 식이섬유소 중 불용성 식이섬유소가 각각 89.21%와 95.74%를 차지하였 다. 꽃송이버섯 원물의 β-glucan 함량은 38.03%으로 유산균 발효 꽃송이버섯 혼합물의 β-glucan 함량 5.44%에 비해 유의적으로 높게 나타났다. 꽃송이버섯 원물에는 유리당 중 glucose와 fructose만 함유하고 있으며, 유산균 발효 꽃송 이버섯 혼합물은 sucrose만을 함유하였다. 총 polyphenol 함량은 꽃송이버섯 원물과 유산균 발효 꽃송이버섯 혼합물 에서 유의적인 차이는 나타나지 않았다. 총 flavonoid 함량 은 유산균 발효 꽃송이버섯 혼합물이 꽃송이버섯 원물에 비하여 유의적으로 높게 나타났다(p<0.05). DDPH radical 소거능은 꽃송이버섯 원물과 발효 꽃송이버섯 혼합물에서 유의적인 차이는 나타나지 않았으나, 대조군인 비타민 C에 비해서는 유의적으로 낮은 DDPH radical 소거능을 나타냈 다(p<0.05). ABTS radical 소거능은 유산균 발효 꽃송이 버 섯 혼합물이 꽃송이 버섯 원물에 비해 유의적으로 높은 것으로 나타났으며, 대조군인 비타민 C와는 유의적인 차이를 보이지 않았다(p<0.05). 꽃송이버섯 원물과 유산균 발효 꽃송이버섯 혼합물의 항산화지수도 비슷한 경향을 보였고, 대조군인 비타민 C에 비해서는 낮았으나, 시료를 첨가하지 않는 음성대조군 보다는 높게 나타났다. 따라서 유산균 발 효 꽃송이버섯 혼합물은 항산화 작용에 긍정적인 영향을 미칠 수 있는 천연소재로서 산업적 활용이 가능할 수 있을 것이다.
        290.
        2016.03 KCI 등재 서비스 종료(열람 제한)
        In present study, the coffee residue was analyzed to finding out physicochemical characteristics and TG analysis that can simulate a pyrolytic kinetic, while comparing with that of chicken residue and food waste. The higher heating value (HHV) of coffee residue was 5,250 kcal/kg that is higher than that of wood pellet (4,300 kcal/kg), Additionally, it showed a good activation energy 72 kJ/mol which is similar with that of other biomass, such as saw dust, wood-chip and so on. It means that the coffee residue is meeting to standard for highest quality of wood pellet, and it would be used as a biomass in the future. However, it never become a fuel without main fuel, such as coal and wood, because its discharge amount is too little. Thus, it has to be applied to existing process, such as power plant which must to meet a RPS regulation. For this, physicochemical characteristics of various biomass have to be analyzed, while considering a discharge amount of them. Therefore, the research result would be provided to reclassification coffee residue to biomass from food wastes in the future.
        291.
        2016.03 KCI 등재 서비스 종료(열람 제한)
        Bakanae (foolish seedling) disease caused by Gibberella fujikuroi creates serious problems in the foremost rice growing countries. This study was conducted to identify new resistance genetic sources to Bakanae disease. Bioassay showed that 11 varieties including Gwangmyeongbyeo, Hawn, Wonseadaesoo, Erguailai etc. were resistant to bakanae disease among 254 rice germplasm. Mismatch ratio between phenotype on bakanae disease bioassay and allele type of RM9, a SSR marker closely linked the bakanae disease resistant QTL, qBK1, were 38.3%. These results suggest that RM9 might be used for selecting qBK1, but it cannot be used for wide range of rice germplasm. Resistant germplasm in this study might be have resistant genes different from qBK1. The eleven varieties resistant to selected in this study will be used to identify new resistant alleles or genes to improve bakanae disease resistance in rice.
        292.
        2016.01 KCI 등재 서비스 종료(열람 제한)
        확률강우량은 수공구조물 설계와 도시방재를 위한 기준 등으로 활용되고 있어, 확률강우량의 산정은 매우 중요하다. 특히 소방방재청에서는 확 률강우량으로 우리나라 시·군 단위로 지역방재성능목표를 설정하고 이에 대한 방재성능평가 및 방재성능목표 달성을 위한 개발계획 수립 시 활용 하고 있다. 본 연구에서는 현재 시·군 단위로 설정되어 있는 목표 강우량을 구(區) 단위로 산정하고자 기상청의 지상기상관측지점(SSS, Surface Synoptic Stations)과 방재기상관측지점(AWS, Automatic Weather Stations)의 강우자료를 활용하여 지점빈도해석 및 지수홍수법을 이용한 지역빈도해석을 통해 지속시간 1시간, 2시간, 3시간 목표강우량을 산정하였다. 이는 서울지역의 지자체별 방재성능 평가 및 방재관련 업무에 참고 자료로 활용할 수 있을 것으로 판단되며, 향후 방재성능목표 설정에 크게 기여할 것으로 판단된다.
        293.
        2016.01 KCI 등재 서비스 종료(열람 제한)
        본 연구에서는 강의평가결과에 영향을 주는 요인들을 실증적으로 밝히고 이를 통제하여 타 당하고 신뢰성 있는 강의평가결과를 공개하고 활용할 수 있는 방안을 모색해 보고자 하였다. 이를 위해 A대학의 4개 학기 강의평가 결과를 자료로 하여 교수자 특성(전임/강사)과 강좌특 성(이수구분, 강좌규모) 및 학생특성(학년, 소속대학)에 따라 분류하여 평가결과가 어떻게 다른 지를 분석하였다. 분석결과 선행연구에서 밝혀진 것과 마찬가지로 교수자 특성과 학생특성, 강 좌특성에 따라 강의평가결과에 유의한 차이가 있다는 것이 확인되었다. 강의평가 결과에서 나 타난 잡음요인을 통제하기 위하여 ‘회귀분석에 기초한 균등화 방법’을 이용하여 사후 조정하였 다. 사후조정 된 점수는 원점수보다 집단 간 차이가 적어 교수업적평가와 같은 총괄적 평가에 적용하는 데 비교적 무리가 없다는 판단을 할 수 있었다. 그러나 이와 같은 수리적 해법이 교 육의 질 개선이라는 강의평가의 본래 목표를 충족시키지는 못하므로 본 연구에서는 강의 평가 잡음요인을 확인하고 이를 근거로 하여 강의평가의 목적에 따라 형성적 기능과 행정적 기능으 로 이원화 할 필요성과 형성적 기능을 강화하기 위한 시사점을 논의하였다.
        294.
        2015.12 KCI 등재 서비스 종료(열람 제한)
        저글루테린 및 저아밀로스 품종인 ‘건양2호’는 ‘중국173 호’와 ‘주남벼’를 각각 모본과 부본으로 인공교배 후 집단육 종법을 통하여 육성한 기능성 품종이다. ‘건양2호’의 출수기 는 영호남 및 중부평야지 보통기 보비재배에서 8월 10일로 ‘남평벼’보다 5일 빠른 중생종이다. 간장은 65 cm로 내도복 성이며, 불시출수와 수발아는 안되는 편이고 내냉성은 ‘남평 벼’와 비슷한 편이다. 잎도열병 밭못자리검정에서 중정도 저항성을 보였으며, 줄무늬잎마름병과 흰잎마름병(K1, K2, K3) 에는 저항성이다. ‘건양2호’의 아밀로스함량은 11.5%로 메벼 와 찹쌀의 중간형태로 불투명한 저아밀로스 품종이며, 단백질 함량은 6.0%로 ‘남평벼’보다 약간 낮으며 소화성 전분인 글 루테린 비율이 63.1%로 ‘남평벼’의 73.8%보다 낮다. ‘건양2 호’의 쌀 수량성은 4.61 MT/ha로 ‘남평벼’보다 9% 감수되었 고, 적응지역은 영호남 및 중부 평야 1모작지이다(품종 등록 번호: 제5105호).
        295.
        2015.12 KCI 등재 서비스 종료(열람 제한)
        Agriculture, rural landscapes are accompanied by a variety of environmental issues. Therefore, it is necessary to study on biodiversity and ecosystem services. Horticulture complex is low groundwater recharge function, it can be evaluated as a facility that biodiversity is impaired. The ecosystem services in agricultural landscapes were obtained 19 kinds of functions. Experts survey Groundwater recharge function (4.13) teeth chapter higher, Water storage (4.05), Amphibian & Reptile habitat (3.96), Aquatic insect habitat (3.92), Flood control (3.87), Water purification (3.86), Avian habitat (3.76 ), Creating landscape (3.74), Vegetation diversity (3.71), Experience, Education (3.69), Biological control (3.48), Fishery habitat (3.42), Climate regulation (3.30), Mammal habitat (3.30), Air quality regulation (3.25 ), Mainenance of genetic diversity (3.25), were analyzed in order Rest area (3.14). Improving capabilities in the Detention Pond, Wetland, Green space, Corridor, Non-Chemical, Program development, Green spaces, Rainwater storage facilities, Water cycle system, Surface water storage facilities, Infiltration trench, Water purification facilities, Permeable pavement. Environmentally friendly, and to contribute to sustainable agricultural development through ecological planning.
        296.
        2015.12 KCI 등재 서비스 종료(열람 제한)
        Various types of parks such as ecological park, dragonfly park, etc. are tried to design in order to resolve different environmental issues in urban areas. Parks are considered organism habitats that not only improve the biodiversity but also give people a chance to observe living organisms in urban area. This study was conducted to select basic materials for planning a butterfly garden through reference reviews. The following 21 species of butterflies belonged to 1 order, 4 families, and 16 genera were selected: Phengaris teleius, Pseudozizeeria maha, Thecla betulae, Argynnis hyperbius, Dichorragia nesimachus, Hestina assimilis, Polygonia caureum, Sasakia charonda, Vanessa cardui, Vanessa indica, Boloria selene, Byasa alcinous, Papilio machaon, Papilio macilentus, Papilio protenor, Papilio xuthus, Papilio bianor, Sericinus montela, Colias erate, Eurema hecabe, and Pieris rapae. 85 species belonged to 22 families, 59 genera, 74 species, 10 varieties, and 1 subspecies were selected for host and nectar plants for butterflies selected above. These results would be expected to useful in butterfly gardening. After that, we think it is necessary to be applied these study results in field. This study requires a test in the butterfly garden. The test results will be make the butterfly-plant matrix.
        297.
        2015.10 서비스 종료(열람 제한)
        the primary objective of this research is to reduce the damage of critical frame structures such as hospitals and schools during and after an earthquake. this study develop the infill panel to allow smaller shear deformation with sliding of the specific element in the panel. As a result, the side sway was significantly reduced in the structure with infill panel, in comparison to the steel frame structure without infill panel during the experimental test
        298.
        2015.10 서비스 종료(열람 제한)
        Asphalt material is visco-elastic material, which is sensitive to temperature and such phenomenon can result in affect to super-structure of concrete trackbed systems under various temperature loads. Consequently, the key objective of this research is to evaluate the performance related to stress changes of wide sleepers on asphalt-concrete trackbed systems corresponding to temperature changes. The range of temperature to represent the season is 60℃∼-10℃ and the numerical analysis was conducted in ABAQUS
        299.
        2015.09 KCI 등재 서비스 종료(열람 제한)
        In order to develop optimum paddy-upland rotation system, we evaluated the 1st and the 2nd upland growth and yield characteristics of foxtail millet, proso millet, sorghum rotated from paddy field and rice rotated from upland in paddy-upland rotation. Average number of ears per hill was 3.3 in the 2nd upland cultivation. The value was greater by 1 ear as compared to 1st upland cultivation (2.2 ears per hill). In average yield per 10a, the 2nd upland cultivation showed 220.3 kg, 23% increased yield compared to the 1st upland cultivation (179 kg per 10a). In average number of ears per hill, the 2nd upland cultivation showed 8.3 ears, increased 4 ears compared to the 1st upland cultivation (4.2 ears per hill). In average yield per 10a, the 2nd upland cultivation showed 152.8 kg, 16.8% increased yield compared to the 1st upland cultivation (130.8 kg per 10a). In average days from seeding to heading of 5 sorghum varieties, there were no significant difference between the 1st (68.6 days) and the 2nd (67.4 days) upland cultivation rotated from paddy field. In the average number of grains per ears, the 2nd upland cultivation showed 2,931.6 grains per ear, 12% increased compared to the 1st upland cultivation (2,619.6 grains per ears). Average yield per 10a of sorghum in the 2nd upland cultivation showed 242.3 kg, 4.6% increased compared to the 1st upland cultivation (231.7 kg per 10a). In growth and yield characteristics of rice in paddy-upland rotation, culm length in paddy-upland-paddy plot showed 82.9 cm, 7.3 cm longer compared to the continuous rice paddy field (75.6 cm). Ear length was also 1 cm longer than that of the continuous rice paddy field. In average number of ears per hill, paddyupland- paddy plot showed 25.0 ears, 4.3 ears more than that of the continuous rice paddy field (20.7 ears per hill). In average yield of rice per 10a, the paddy-upland-paddy rotation plot showed 526.8 kg, 9.8% higher yield compared to the continuous rice paddy field (479.9 kg per 10a).
        300.
        2015.09 KCI 등재 서비스 종료(열람 제한)
        This experiment was carried out to determine the optimum planting density for rice pot seedling cultivation in wheat-rice double cropping system in Honam plain area. A mid-late maturing rice variety ‘Chinnong’ was raised in pot seedling tray and conventional tray for 30 days, and then transplanted on June 25 in 2012 and 2013. Four different planting densities (15.2, 18.9, 21.6, and 25.3 hills per m 2 ) in pot seedlings were applied as treatment. Conventional tray seedling was implicated as control at a single planting density of 27.8 hills per m 2 . In this experiment, the number of effective tillers was increased as planting density increasing, but stem diameter was decreased. Pot seedling showed higher stem diameter and effective tillers than the control. Heading dates of pot seedling plots were not significantly different between the planting densities but 2 days faster than the control. Culm length, number of panicles, panicle length, and ripening grain ratio were higher in pot seedling compared to the control, but 1000-grain weight showed no significant difference. Milled rice yields in pot seedlings ranged from 5.19 to 5.43 t ha -1 , and the highest yield was observed in 21.6 hills per m 2 . Head rice ratios in pot seedlings and the controls were not significantly different. Above results on planting density of rice pot seedling cultivation would be applicable to wheat-rice double cropping and also to late transplanting cultivation of rice single cropping.