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Effect of wide-narrow row arrangement in mechanical pot-seedling transplanting and plant density on yield formation and grain quality of japonica rice

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Journal of Integrative Agriculture 2020年第5期19卷 1197-1214页

作者： HU Qun JIANG Wei-qin QIU Shi XING Zhi-peng HU Ya-jie GUO Bao-wei LIU Guo-dong GAO Hui ZHANG Hong-cheng WEI Hai-yan Jiangsu Key Laboratory of Crop Genetics and Physiology/Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops/Agricultural College Yangzhou UniversityYangzhou 225009P.R.China

Mechanical pot-seedling transplanting is an innovatively developed transplanting method that has the potential to replace mechanical carpet-seedling transplanting. However, the initial pot-seedling transplanting machine lacked optimized density spacing and limited yield potential for japonica rice. Therefore, ascertaining the optimized density by wide-narrow rows and the appropriate transplanting method for yield formation and grain quality of japonica rice is of great importance for high-quality rice production. Field experiments were conducted using two japonica rice cultivars Nanjing 9108 and Nanjing 5055 under three transplanting methods in 2016 and 2017: mechanical pot-seedling transplanting with wide-narrow row(K, average row spacing of 30 cm);equidistant row(D, 33 cm×12 cm);and mechanical carpet-seedling transplanting(T, 30 cm×12.4 cm). In addition, five different density treatments were set in K(K1–K5, from 18.62×10~4 to 28.49×10~4 hills ha^(–1)). The results showed that the highest yield was produced by a planting density of 26.88×104 hills ha^(–1) in mechanical pot-seedling transplanting with wide-narrow row with a greater number of total spikelets that resulted from significantly more panicles per area and slightly more grain number per panicle, as compared with equidistant row, and yield among density in wide-narrow row showed a parabolic trend. Compared with mechanical carpet-seedling transplanting, the treatment of the highest yield increased yield significantly, which was mainly attributed to the larger sink size with improved filled-grain percentage and grain weight, higher harvest index, and increased total dry matter accumulation, especially the larger amount accumulated from heading stage to maturity stage. With the density in wide-narrow row decreasing, processing quality, appearance quality, and nutrition quality were all improved, whereas amylose content and the taste value were decreased. Compared with mechanical carpet-seedling transplanting,

关键词： density grain quality japonica rice transplanting methods wide-narrow row yield formation

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QR factorization for row or column symmetric matrix

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Science China Mathematics 2003年第1期46卷 83-90页

作者：邹红星戴琼海李衍达王殿军 Department of Automation Tsinghua University Department of Mathematical Sciences Tsinghua University

The problem of fast computing the QR factorization of row or column symmetric matrix isconsidered. We address two new algorithms based on a correspondence of Q and R matrices between the rowor column symmetric matrix and its mother matrix. Theoretical analysis and numerical evidence show that, fora class of row or column symmetric matrices, the QR factorization using the mother matrix rather than therow or column symmetric matrix per se can save dramatically the CPU time and memory without loss of anynumerical precision.

关键词： QR factorization, row or column symmetric matrix, fast computation.

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Generative computer simulation for parallel layout of multi-story row house cluster

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Science China(Technological Sciences) 2010年第7期53卷 1785-1791页

作者： DING XiYing1,2 1 ZhenjiangUniversity, Hangzhou 310058, China 2 Zhejiang University of Science & Technology, Hangzhou 310058, China Zhenjiang University Hangzhou China Zhejiang University of Science & Technology Hangzhou China

This study has established the functions between the environmental conditions and the inhabitants’ preferences for multi-story row house cluster with parallel layout, based on the data from the questionnaires’ in Beijing. A program has been written with multi-agent system and generative computer simulation approaches. The emergence candidate layout plans can be referenced and chosen by architects.

关键词： multi-agent system bottom up generative computer simulation multistory row house cluster parallel layout

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Thermal bidirectional gap probability model for row crop canopies and validation

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Science China Earth Sciences 2003年第12期46卷 1241-1249页

作者：阎广建蒋玲梅王锦地陈良富李小文 Research Center for Remote Sensing and GIS Department of Geography and Beijing Key Laboratory for Remote Sensing of Environment and Digital Cities Beijing Normal University Beijing 100875 China LARSIS Institute of Remote Sensing Application Chinese Academy of Sciences Beijing 100101 China Department of Geography and Center for Remote Sensing Boston University Boston MA 02215 USA

Based on the row structure model of Kimes and the mean gap probability model in single direction, we develop a bidirectional gap probability model for row crop canopies. A concept of overlap index is introduced in this model to consider the gaps and their correlation between the sun and view directions. Multiangular thermal emission data sets were measured in Shunyi, Beijing, and these data are used in model validation in this paper. By comparison with the Kimes model that does not consider the gap probability, and the model considering the gap in view direction only, it is found that our bidirectional gap probability model fits the field measurements over winter wheat much better.

关键词： row crop, bidirectional gap probability, thermal emission, hot spot effect.

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Study on the law of radiant directionality of row crops

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Science China(Technological Sciences) 2000年第S1期43卷 70-82页

作者：陈良富庄家礼柳钦火徐希孺田国良 Insitute of Remote Sensing and GIS Peking University Beijing China Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing China

The style of crops planting is frequently in row-structure, the row-structure style may result in big difference among the sunlit, shaded soil surface and foliage temperatures and cause pixel component to vary in azimuth orientation, these further lead to the change of radiant directionality of row crops in the zenith and azimuth orientations. Since the row crops are often tackled as isotropic in the azimuth orientation based on continuous vegetation assumption, big errors will be brought about. In order to eliminate the errors, it is necessary to study the law of radiant directionality of the row crops. In this paper, Monte Carlo method has been employed to simulate the angular effects on radiation caused by row architecture parameters. The simulated results show that the parameters, for example, row height, row width, row interval between the neighbor rows and the leaf area index have significant influences on the radiant directionality, but the azimuth orientation ranks the first among the parameters.

关键词： row crops radiant directionality Monte Carlo simulation.

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Effects of Tillage and Planting Methods on Narrow and Wide row Cotton Production

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Agricultural Sciences 2018年第7期9卷 792-803页

作者： Michael W. Marshall Ahmad Khalilian Clemson University Edisto Research and Education Center Blackville SC USA Clemson University Department of Agricultural Sciences Clemson SC USA

Cotton (Gossypium hirsutum L.) is an economically important crop for the Southern United States. The southern US also has a long growing season suitable for double cropping a second crop after small grains;however, the harvest date for the small grains typically occurs after the optimum planting window for cotton which reduces yield potential. A relay intercropping system was developed at Clemson University that allows interseeding of cotton into standing wheat 2 to 3 weeks before harvest with interseeded cotton yields similar to the conventional mono-cropped cotton. Therefore, the objectives of this study were 1) to determine the optimum tillage and planting methods for narrow row (76-cm) and wide row (97-cm) cotton, and 2) to compare narrow and wide row systems for conventional tillage cotton, cotton interseeded into standing wheat, and cotton planted into a terminated wheat cover crop on coastal plain soil. Two replicated tests were conducted to accomplish these objectives. In Study 1, conventional narrow row cotton combined with a deep tillage operation using Paratill yielded 23% more than conventional wide row cotton which had a deep tillage operation with a subsoiler just before planting. There were no differences between the conventional (97-cm row spacing) mono-crop and interseeded cotton yields. In Study 2, there was no significant difference in yield between narrow-row and wide-row cotton for each cropping system during the two years study. Both wide and narrow-row full season cotton had significantly higher yields than interseeded and cover crop planting systems in year two of the study. The two conservation cropping practices, wheat used as a cover crop and interseeding, showed considerable promise for reducing energy requirements, soil erosion, and wind-borne cotton damage associated with bare soil in conventional tillage. This research demonstrates the benefits of interseeding and narrow row spacing for sustainable cotton production in coastal plain so

关键词： Conservation Relay Cropping Interseeding Double Crop Cotton row Spacing

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Influence of Various row Spacing on the Yield and Yield Components of Raya Anmol and Faisal Canola under Coastal Climatic Conditions of Lasbela

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American Journal of Plant Sciences 2014年第15期5卷 2230-2236页

作者： Muhammad Waseem Dost Mohammad Baloch Imran Khan Department of Agronomy University of Agriculture Faisalabad Pakistan Faculty of Agriculture Lasbela University of Agriculture Water and Marine Sciences Uthal Pakistan

During 2013-2014 a field experiment was conducted at experimental area of Faculty of Agriculture under Lasbela University of Agriculture, Water and Marine Science, Uthal, Lasbela to evaluate the influence of various row spacing on the yield and yield components of Raya Anmol and Faisal Canola under coastal climatic conditions of Lasbela. Randomized complete block design (RCBD) with factorial arrangement having 3 replications was used. Experiment comprises two canola varieties, C1 = Raya Anmol, C2 = Faisal Canola at 3 row spacing distances RS1 = 30 cm, RS2 = 45 cm and RS3 = 60 cm respectively. Result showed that yield and yield contributing traits are significant. It was concluded that seed yield of C1 (Faisal Canola) was better as compared to that of Raya Anmol. row spacing (RS3 = 60 cm) yielded more crop canopy and the highest number of pod per plant, pod length and seed yield under agro climatic condition of Lasbela as compared to other densely arranged row spacing.

关键词： Canola Cultivar row Spacing Coastal Environment

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Experimental Investigations of the Shear Capacity of Nails in a row

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Open Journal of Civil Engineering 2013年第3期3卷 173-181页

作者： Christian OSorensen Ruth-Marie Nymark Lars Baastad Institute of Technology Civil Engineering and Architectural SectionThe Norwegian University of Life SciencesAasNorway Stor-Elvdal Kommune(Stor-Elvdal Municipality) KoppangNorway Venator(Consultants) OsloNorway

Tests of the capacity of shear connections consisting of nails in a row placed at distances 7, 10 and 14d, “d” being the cross-sectional dimension of the nail, versus single nail capacities, were executed. The performed tests do support the connotation that no reduction should be required for nails of diameter 2.8 mm or less in a row, provided that nails are spaced sufficiently far apart for wood cracking not to occur. At the ultimate capacity of the joint, all such thin nails in a row will be yielding, having developed plastic hinges, i.e. each single nail will have developed its ultimate capacity. Hence, the ultimate capacity of the connection will be each nail’s capacity times the number of nails in the row. The force pr. nail increases subsequent to the development of a plastic hinge. This is likely due to the axial pullout-force, i.e. the ultimate capacity of a shear connection is higher than the force required for developing plastic hinges in the nails. This additional capacity-reserve may also partly be attributed to the rotational resistance of nails. The number of nails in a row should make insignificant difference in the pr. nail capacity, as long as no wood cracking takes place. Thus, applying elastic theory to nails in a row does not seem relevant. This is in contrast to bolt-connections.

关键词： Nails Shear Connections row Spacing Capacities

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Usefulness of an Anisotropic Diffusion Method in Cerebral CT Perfusion Study Using Multi-Detector row CT

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Open Journal of Medical Imaging 2015年第3期5卷 106-116页

作者： Kenya Murase Takafumi Nanjo Yoshifumi Sugawara Masaaki Hirata Teruhito Mochizuki Department of Medical Physics and Engineering Division of Medical Technology and Science Faculty of Health Science Graduate School of Medicine Osaka University Osaka Japan Department of Radiology Graduate School of Medicine Ehime University Ehime Japan

Purpose: To present an application of the anisotropic diffusion (AD) method to improve the accuracy of the functional images of perfusion parameters such as cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) generated from cerebral CT perfusion studies using multi-detector row CT (MDCT). Materials and Methods: Continuous scans (1 sec/rotation ×60 sec) consisting of four 5-mm-thick contiguous slices were acquired after an intravenous injection of iodinated contrast material in 6 patients with cerebrovascular disease using an MDCT scanner with a tube voltage of 80 kVp and a tube current of 200 mA. New image data were generated by thinning out the above original images at an interval of 2 sec or 3 sec. The thinned-out images were then interpolated by linear interpolation to generate the same number of images as originally acquired. The CBF, CBV and MTT images were generated using deconvolution analysis based on singular value decomposition. Results: When using the AD method, the correlation coefficient between the MTT values obtained from the original and thinned-out images was significantly improved. Furthermore, the coefficients of variation of the CBF, CBV and MTT values in the white matter significantly decreased as compared to not using the AD method. Conclusion: Our results suggest that the AD method is useful for improving the accuracy of the functional images of perfusion parameters and for reducing radiation exposure in cerebral CT perfusion studies using MDCT.

关键词： Anisotropic Diffusion Method Cerebral CT Perfusion Study Multi-Detector row CT Radiation Exposure

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Effect of row spacing and direction of sowing on yield and yield attributing characters of wheat cultivated in Western Chitwan, Nepal

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Agricultural Sciences 2013年第7期4卷 309-316页

作者： Bisheshwor Prasad Pandey Komal Bahadur Basnet Madan Raj Bhatta Shrawan Kumar Sah Resham Bahadur Thapa Tanka Prasad Kandel Department of Agroecology Aarhus University Research Centre Foulum Tjele Denmark Institute of Agriculture and Animal Science Tribhuvan University Rampur Nepal National Wheat Research Program (NWRP) Rupendehi Nepal

A field experiment was conducted to study the growth and productivity of wheat as affected by row spacing and direction of sowing at Rampur, Chitwan, Nepal during the 2007-2008 wheat growing season. The experiment was carried out in 3-factors factorial randomized complete block design comprising two varieties (Gautam and BL-2800), three row spacings (15, 20 and25 cm) and two row directions of sowing (east-west and north-south). The effects of variety and row direction of sowing on grain yield were significant (p row spacing treatment. BL-2800 variety produced higher grain yield (3.53 t·ha-1) as compared to Gautam (3.11 t·ha-1). Both wheat varieties yielded about 11% higher (p < 0.05) grain in the north-south sowing as compared to the eastwest sowing.

关键词： Grain Yield row Direction row Spacing Triticum Aestivum Wheat Variety

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