• 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.

• 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 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.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.8 no.1
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• pp.69-81
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• 1970

1. Four soybean varieties in pure stand and mixtures were grown in 20 competition treatments of genotypes at within-row spacings of 5, 10, 20, 40, and 80 cm and were investigated in 10 characters for different genotypes. 2. Yield, weight of 100 seeds, height, number of branches, pods per plant, and seeds per pod were highly significant for within-row spacing treatment. 3. There was no spacing treatment effect for number of nodes and days to flower. Maturity did not respond equally in four varieties for spacing effect. 4. Fruiting period was influenced by spacing treatment. Height and number of branches were increased as within-row spacings were increased. Seed yield per area was increased oppositely. 5. Difference between fertilizing and non-fertilizing treatment was not significant in this experiment. At 80 cm spacing no competition effect occurred for yield. 6. In the competition effect, Kumkang Daerip was strong competitor ani Chungbuck Back and Shelby were weak competitors. 7. The within-row spacing of uniformity in roder to increase yield per area was proved as 20 cm in this study. 8. Oil percent was increased as spacings were increased and protein percent was as spacings were decreased.

• 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 Environmental Agriculture
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• v.34 no.3
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• pp.204-209
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• 2015

BACKGROUND: Radish (Raphanus sativus L.) is cultivated worldwide and one of important vegetables in Korea where year-round production of radish is possible. Most of radishes in autumn are cultivated with double-row spacing except for Gangwon-do where sing-row spacing is predominant. However, no research has been conducted on double-row spacing in radish cultivation so far. This study was conducted to reveal the optimum double-row spacing in autumn cultivation of radish. METHODS AND RESULTS: Using top two popular autumn radish cultivars 'S' and 'C', seeds were sown in spacing between rows of $55{\times}25$, $45{\times}25$, $35{\times}25$ and $25{\times}25cm$, and that within rows of $35{\times}28$, $35{\times}25$, $35{\times}22$ and $35{\times}19cm$. Plants were harvested 58 days after sowing and leaf weight, length and number, and root weight, length sugar content and pithiness were investigated. In the spacing between rows, no significant difference was observed in leaf weight, length and number in both cultivars; however, 25 cm of spacing between rows significantly reduced the root length and weight in 'S' and 'C' cultivars, respectively. In spacing within rows, 28, 25 and 22 cm did not affect fresh root weight in both cultivars, producing appropriate radish roots of 1,500g on average. However, 19 cm of spacing within rows did not reduced fresh root weight in 'S' cultivar but did significantly in 'C' cultivar (1148.3 g). Sugar contents and pithiness of roots were also affected by spacing but its effect was very small and different between cultivars. CONCLUSION: It is suggested that optimum double-row spacing in autumn radish cultivation is 35 cm and 22 cm of spacing between and within rows, respectively, the spacing that did not reduce the yield and quality of radish roots in two popular autumn radish cultivars.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.1
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• pp.50-58
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• 2000

Experiments were carried out to obtain the effects of nozzle configuration and jet to jet spacing on the heat transfer characteristics of single line of circular water jets impinging on a constant heat flux plane surface. The nozzle configurations are Cone type, Reverse cone type and Vertical circular type, and the nozzle arrays are single jet(nozzle dia. 8 mm), 1 row of 3 jets and 1 row of 5 jets. Jet velocities ranging from 3m/s to 8m/s were investigated for the nozzle to target plate spacing of 80 mm. For the Cone and Reverse cone type nozzle arrays, the average Nusselt number of 1 row of 5 jets was larger than that of 1 row of 3 jets at Re$_{D}$<45000, but that of 1 row of 3 jets was larger than that of 1 row of 5 jets at $Reo\le45000$. For the Vertical circular type nozzle, however, the average Nusselt number of 1 row of 3 jets was larger than that of 1 row of 5 jets at all jet velocities. In the condition of fixed mass flow rates, the maximum heat transfer augmentation was obtained for 1 row of 5 jets and was over 2 times larger than that of the single jet for all nozzle configurations. The nozzle configurations that produce the maximum average Nusselt number are as follows: For 1 row of 3 jets, the Vertical circular type at $Reo\le45000$ and the Reverse cone type at $Reo\le45000$. But, they are the Reverse cone type at Re$_{D}$<55000 and the Vertical circular type at$Reo\le55000$ for 1 row of 5 jets.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.1
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• pp.59-66
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• 2000

In a previous paper, we have examined the effects of nozzle configuration and jet to jet spacing on the heat transfer of 1 row of circular water jets. In this paper, experiments have been conducted to obtain the effects of nozzle to target plate distances on the heat transfer of 1 row of 3 jets and 1 row of 5 jets. The nozzle configurations are Cone type, Reverse cone type and Vertical circular type. Nozzle to target plate distance H was varied from 16 mm(H/D=2) to 80mm(H/D=10). For fixed value of mass flow rate and nozzle to target plate distance, larger values of average Nusselt number were obtained for the smaller jet to jet spacing. For the array of water jets, the average heat transfer was decreased slightly with increasing nozzle to target plate distance at low jet velocity of $\textrm{V}_{o}$=3 m/s. However, except for $\textrm{V}_{o}$=8 m/s of 1 row of 5 jets, it was increased with increasing nozzle to target plate distance at high jet velocity of $\textrm{V}_{o}$$\geq$6m/s. We proposed to apply the nozzle configuration of maximum average heat transfer to each nozzle to target plate distance for 1 row of 3 jets, and, it was Reverse cone type nozzle for 1 row of 5 jets(Reynolds number$\geq$36000).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.7 no.1
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• pp.153-160
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• 1969

Experiments on sweet sorghum(sorgo) with different population per unit area were conducted from 1966 to 1968 for the first time in Korea. By increasing plant population stalk weight, refinable sugar and seed weight per plot were increased, but stalk weight per plant, brix percentage, sugar content, stem diameter and 1, 000 seed weight were decreased. Plant height, maturity and lodging were not affected by the treatments. The result obtained has suggested that the effects of plant spacing within row on the characteristics of plant growth and on yields were greater than those of row width. Negative correlations existed between sugar content and sugar yield, and seed weight per plant and seed yield. The optimal plant population in this study ranged from 16, 700 to 22, 200 plants per 10a, row width of 60cm and plant spacing in row of 15 to 20cm resulted in the highest sugar and seed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.2
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• pp.212-217
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• 1981

The evaluate the effect of plant spacing on cured leaf of burley tobacco, the row spacings divided to 90, 105, 120cm and hill spacings to 30, 35, 40cm within each row. Growth amount per plant increased with thinner row and wider hill spacing in the same planting density. Relative light intensity increased with thinner row spacing in cutters and leaf and showed the positive correlation with quality. When the planting density was equal, the wider hill spacings, the more effective in utillization of solar radiation. The more plants per l0a were, the greater yield was obtained, and in the case of 3,200 plants per 10a (the most dense planting plot) was 267kg. But, quality, total-alkaloid and total-nitrogen content decreased with dense planting. Value per 10a was highest in the plots of 90 $\times$ 40cm and $105{\times}40cm$. In conclusion the optimum density level was 2,400 to 2,700 plants per 10a and spacing of tobacco either in 105 $\times$ 35 cm or 105 $\times$ 40cm seems to be most appropriate.