• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.4
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• pp.357-362
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• 1981

This study was conducted to examine the best population density and agronomic characteristics affected by different row-widths and planting-spaces within row in safflower. As both row-width and spacing were narrowed, plant height and height to first branch were increased, and the number of branch per plant showed decrease. Plant height showed negative correlation with row-width, height to first branch showed negative correlation with row-width x spacing, and number of branch per plant had positive correlation with row width, and row-width x spacing but negative correlation with plant height. Yield was affected by spacing and row-width x spacing. In spacing, 5cm plot performed the best yield, and 30 x 5cm population density was the best cultural method to increase safflower yield. Yield had negative correlation with spacing and row-width x spacing, but positive correlation with height to first branch.

• Geomechanics and Engineering
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• v.13 no.4
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• pp.621-640
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• 2017

The double-row long-short composite anti-sliding piles system is an effective way to control the landslides with high thrust. In this study, The double-row long-short composite anti-sliding piles with different load segment length (cantilever length) and different pile row spacing were studied by a series of physical tests, by which the influences of load segment length of rear-row piles as well as pile row spacing on the mechanical response of double-row long-short composite anti-sliding pile system were investigated. Based on the earth pressures in front of and behind the piles obtained during tests, then the maximum bending moments of the fore-row and the rear-row piles were calculated. By ensuring a equal maximum moments in the fore-row and the rear-row piles, the optimum lengths of the rear-row piles of double-row long-short composite system under different piles spacing were proposed. To investigate the validity of the reduced scale tests, the full-scale numerical models of the landside were finally conducted. By the comparisons between the numerical and the physical test results, it could be seen that the reduced scale tests conducted in this study are reliable. The results showed that the double-row long-short composite anti-sliding piles system is effective in the distribution of the landslide thrust to the rear-row and the fore-row piles.

• Journal of Biosystems Engineering
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• v.40 no.1
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• pp.35-46
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• 2015

Purpose: To present a flexible and accurate autonomous solution for creating any desired row spacing value between the hydroponic gullies in multilayer growing units, and evaluate the capabilities and performance of the relevant automated system through the use of virtual prototyping technique. Methods: To build the virtual prototype of the system, CAD models of its different parts, including an autonomous vehicle and the mechanical mechanisms embedded in the multilayer growing unit, were developed and imported into the RecurDyn simulation software. In order to implement the automated row spacing operation, three spacing modes with different loading cycles and working steps were defined, and the operation of the system was simulated to obtain the target row spacing values specified for each of these modes. Results: Motion profiles related to the horizontal displacement of: 1) the lower and upper sliding bars installed in the cultivation layers, and 2) the hydroponic gullies, during the simulation of the system operation, were generated and analyzed. No deviation from the specified target spacing values was observed at the end of simulations for all spacing modes. Conclusions: The results of the motion analysis obtained by simulating the system operation confirm the effectiveness of the control scheme proposed for automated row spacing of gullies. It was also found that proper sequencing of the loading cycles and the precision of the working strokes of the upper bars are the critical factors for establishing a certain row spacing value. Based on the simulation results, precise control of the back and forth motions of the upper bars is highly necessary for sound operation of the real system.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.7 no.1
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• pp.133-137
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• 1969

This experiment was conducted to determine the optimum row width and plant spacing within row under the tropical environment for a leading soybean variety Palmetto and it was carried out at Eakmat Experiment Station in Vietnam. The experiments were arranged in a split plot design with four replications and the test was repeated twice in two years. Variations for seed yield due to the distance between rows were significant at 1 per cent level in 1967 test(dry season growing) and at 5 per cent level in 1968 test. Significant differences for plant height, lodging, maturity, number of branches per plant, and number of pods per plant due to the row width were not found in both tests, while significant differences in difference spacing within row was found in all traits studied. Interaction between width of row and spacing within row for seed yield and plant height were found at five percent level in 1967 test. These results indicate that close planting may increase in seed yield and plant height in both seasons, and decrease in loadging. From these studies, one could be understood that the plant population, particularly in dry season, plays decisive roles on seed yield in soybean culture, and the maximum plant height and minimum value of lodging index were also observed in closest spacing plots. The highest soybean yield in late planting would be expected by a combinations of 30 cm(between rows)${\times}$5cm(between hills) plot, while 40cm ${\times}$ 5cm planting method would be suggested for rainy season growing. Highest seed yield was obtained at closet spacing in both dry and rainy season, and these results led to drilling method in seeding where about 20 seeds per meter of row could be recommended. Besides the seed yield, the close planting may produce some advantages, such as increase plant height and decrease lodging, weeds and erosion of surface soil.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.8
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• pp.538-544
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• 2010

An experimental investigation is presented to study the effect nozzle spacing, jet to plate spacing and Reynolds number on the local heat transfer to normally upward impinging submerged circular water jets on a flat heated surface. Nozzle arrays are a single jet(nozzle dia. = 8 mm), a row of 3 jets(nozzle dia. = 4.6 mm, nozzle spacing = 37.5 mm) and a row of 5 jets(nozzle dia. = 3.6 mm, nozzle spacing = 25 mm), and jet to plate spacing ranging from 16∼80 mm(H/D = 2∼10) is tested. Reynolds number based on single jet exit condition is varied 30000∼70000($V_o$ = 3∼7 m/s). Except for the condition of H/D = 10, the average Nusselt number of multi-jet is higher than that of single jet. For H/D = 2, average Nusselt number is increased by 50.3∼82.5% for a row of 3 jets and by 52.9∼65.2% on a row of 5 jets when compared to the average Nusselt number on the single jet.

• Korean Journal of Plant Resources
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• v.17 no.2
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• pp.102-106
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• 2004

To determine the optimal planting density of wanggol in southern areas of Korea, Gangsan early local, the highest yielding variety was grown under four different plant density. Yield components such as stem length, number of tiller, stem diameter were highest at the plots with 18 cm row spacing and 18 cm plant spacing. Dry cortex and medulla yield were highest at the plots of 18 cm row spacing and 18 cm plant spacing. Judging from the results reported above, at optimum planting density of wanggol seemed to be 18 cm row spacing and 18 cm plant spacing.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.4
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• pp.335-338
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• 1992

A Cheju-leading mungbean cultivar Seonhwanogdu was seeded at 20, 30, 40, 50 and 60cm row width with within-row plant spacing of 10cm in mid-June of 1988 to 1990 to determine effects of row width on growth and seed yield of mungbean in Cheju area. Initial flowering and maturing dates were not influenced by the row width. Stem length, pods per plant, seeds per pod, 1000-seed weight linearly decreased as row width decreased because planting density increased. The relationship between seed yield and row width was quadratic, and the optimum row width with within-row plant spacing of 10cm for higher yield of mungbean was 40cm in Cheju.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.07a
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• pp.95-102
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• 2000

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.07a
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• pp.103-110
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• 2000

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.11a
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• pp.589-590
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• 2008

Sound absorption characteristics of audience seating is very important when design and simulate room acoustics of concert halls or multi-purpose auditoriums. Sound absorption characteristics of audience seats were measured in reverberation chamber by varying the row to row spacing and number of audiences. By the increment of the row to row spacing, sound absorption characteristics in mid frequency band was increased. Also, sound absorption was proportionated to the number of audience.