• Korean Journal of Medicinal Crop Science
• /
• v.5 no.1
• /
• pp.67-71
• /
• 1997

Bupleurum falcatum is one of the oldest medicinal crop spontaneously generated as well as cultivated by man and successfully grown during the summer season in Korea. This study was conducted to examine the effect of planting density in the row spacing and hill spacing system using machine seeder on major agronomic traits, yield and labor saving. In 1993 and 1994, a spilt plot design was used with row spacing as the main plot and hill spacing as subplot. Labor saving efficency of the machine seeder reduced 96% than the hand seeding in sowing time required. Number of seeding stand increased, but stem height and number of nodes did not affect with different density in each row and hill spacing. There were reduced with narrow hill spacing on stem diameter, number of branches, shoot weight and root traits. There was no significant interaction between row and hill spacing for any major traits studied except shoot weight. Yield was more increase at 20cm than at 30cm row spacing. For these studies the optiomum density appears to be between drilling or 5cm hill spacing with 20cm row spacing. A highly significant positive correlation was appeared between number of seedling stand and root yield.

• Journal of Advanced Marine Engineering and Technology
• /
• v.22 no.6
• /
• pp.844-853
• /
• 1998

Natural and forced convection experiments were carried out in order to investigate the effects of channel spacing gap between protrusions and number of rows of protrusion, In natural convection the optimum channel spacing was found to be approximately 20mm regardless of the protrusion gaps. For optimum channel spacing the heat transfer coefficients were converged to an asymptotic value after the fourth row. The heat transfer coefficient for each row approaches to constant values for protrusion gaps larger than 10 mm. An experimental correlation has been suggested by using a modified Rayleigh number based on the dimensionless characteristic length(G/L). In forced convec-tion the heat transfer coefficients were not merged to an asymptote until the fifty row and increases as the channel spacing at the constant Reynolds number decreases.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.8 no.1
• /
• pp.69-81
• /
• 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 Environmental Agriculture
• /
• v.34 no.3
• /
• pp.204-209
• /
• 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.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.21 no.9
• /
• pp.1115-1125
• /
• 1997

Experiments have been conducted to obtain local and average heat transfer coefficients associated with impingement of a row of circular, free surface-water jets on a constant heat flux surface. Nozzle arrays are a row of 3 jets (nozzle dia.=4.6 mm) and a row of 5 jets (nozzle dia.=3.6 mm), and the nozzle configuration is Reverse cone type revealed good performance in heat transfer. Nozzle-to-plate spacings ranging from 16 mm to 80 mm were investigated for two jet center to center spacings 25 mm and 37.5 mm in the jet velocity of 3 m/s (R $e_{D}$=27000) to 8 m/s (R $e_{D}$=70000). For a row of 3 jets and a row of 5 jets, the stagnation heat transfer of the central jet is lower than that of adjacent jets. In the wall jet region between jets, for small nozzle-to-plate spacing and large jet velocity, the local maximum in the Nusselt number was observed, however, for small jet velocity or large nozzle-to-plate spacing, the local maximum was not observed. Except for the condition of $V_{O}$=8 m/s and H/D=10, the average Nusselt number reveals the following ranking: a row of 5 jets, a row of 3 jets, single jet. For a row of 3 jet, the maximum average Nusselt number occurs at H/D=8 ~ 10, and for a row of 5 jets, it occurs at H/D=2 ~ 4. Compared with the single jet, enhancement of average heat transfer for a row of 3 jets is approximately 1.52 ~ 2.28 times, and 1.69 ~ 3.75 times for a row of 5 jets.ets.s.

• The Journal of the Acoustical Society of Korea
• /
• v.34 no.4
• /
• pp.282-287
• /
• 2015

This paper examines the combinations of factors influencing the absorption characteristics of theatre chairs. One-tenth scale model chairs and listeners that closely approximated the absorption characteristics of full scale theatre chairs were used to measure the interactive effects of the test variables on the chairs absorption characteristics. The test variables were the type of chairs, the row spacing, as well as the presence of people and carpet. The variations of absorption increments with varied row spacing tended to be smallest when the chairs were less absorptive, i.e. with less carpet or occupants. The incremental effects of adding occupants or carpet averaged over three row spacings varied over frequency.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.12 no.1
• /
• pp.50-58
• /
• 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 CROP SCIENCE
• /
• v.63 no.4
• /
• pp.378-383
• /
• 2018

The goal of this study was to examine the growth and yield according to planting density in wide-row drill seeding cultivation suitable for mechanized harvesting. We evaluated effects depending on planting densities [row spacing (30, 40, 50, and 60 cm) and plant spacing (10, 15, and 20 cm)] and cultivars ('Hongeon' and 'Arari') on growth and yield of Adzuki Beans (Vigna angularis (Willd.) Ohwi Ohashi). When row spacing decreased, the stem length increased in 'Arari' but decreased in 'Hongeon.' The stem diameter and number of branches in both the cultivars decreased with a decrease in row spacing. The pod height increased with lower planting densities. The greatest height values recorded in 'Hongeon' and 'Arari' were 5.0 cm and 8.8 cm in $30{\times}10cm$ and $50{\times}10cm$ treatments, respectively. The number of pods and number of seeds in both cultivars tended to increase with a decrease in planting density. On the other hand, in 100-seed weight, there was a difference in planting density in 'Hongeon', but no difference in 'Arari'. The highest yield was at the planting density of $40{\times}15cm$ in both 'Hongeon' and 'Arari', $285kg{\cdot}10a^{-1}$ and $374kg{\cdot}10a^{-1}$.

• Journal of the Korean Geotechnical Society
• /
• v.24 no.4
• /
• pp.23-36
• /
• 2008

This study describes model tests on instrumented rectangular-shaped passive row piles embedded in horizontal sand-ground undergoing lateral soil movement. We tried to find the property of row piles dependent on the shape of pile, including the position of the pile in row, pile spacing, and soil movement. The results of test are as follows. The lateral earth pressure diagram variously appeared to be triangle, trapezoid and rectangular by shape and position of pile. The outer pile has a larger bending moment than the inner pile in the case of B-type, the inner piles has larger one than outer pile in case of H-type. $R_f$ (the ratio of resistance to lateral soil movement) was found to increase with increasing pile spacing irrespective of pile-shape. Y/L (location of action of lateral resistance force) for $d_s$ (displacement of soil) and $S_h$ (spacing of pile) appeared to be nearly regular position, and H-type is higher than B-type.

• Journal of Environmental Science International
• /
• v.25 no.6
• /
• pp.749-756
• /
• 2016

This study shows how the growth of the top part of plants cultivated using the single-row strawberry method, with 12 cm plant spacing, as well as that of plants cultivated through conventional planting, is characterized by the presence of many leaves in the first flower cluster harvest. The leaf area and crown diameter were the largest in the 12 cm spacing method. The hight top fresh weight (59.2 g) was detected wen the 12 cm spacing method was used followed by conventional planting and, 9 cm and 6 cm spacing method. The K and Ca contents in the first flower cluster were the highest when the 12 cm spacing method (2.0% and 2.1%, respectively) and conventional planting, (0.42% and 0.86%, respectively) were used, and these values were significantly higher than the K and Ca contents obtained using the other two methods. The N, P, Mg, Fe, and B contents show no significant differences across the planting methods. The sugar content of the first flower cluster fruits was the highest when the 12 cm spacing method was used, while the sugar content of the fourth flower cluster fruits was highest after conventional planting. Firmness was the highest in the first, third, and fourth flower clusters after conventional planting, while no significant differences were observed for the 6 cm, 9 cm, and 12 cm spacing methods. A yield of 25 g or above during November to December was observed to be the highest when the 12 cm spacing method was used, while a yield of 10-16 g was the highest when both the 9 cm and 12 cm spacing methods werw used. The yield of products in January-April was the highest when the 12 cm spacing and conventional planting methods were used, and total product yield was also the highest for these methods. A significant portion of non-marketable products (39 g) was obtained when the conventional planting method was used.