• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.3
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• pp.252-258
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• 1985

An experiment was conducted at the Yeongnam Crop Experiment Station to obtain basic informations about cultural techniques for high yielding by manipulating plant spacing using two rice cultivars, Samgangbyeo (Indica/Japonica type) and Nakdongbyeo (Japonica type), and four plant spacings, 10${\times}$10cm, 20${\times}$20cm 30${\times}$30cm and 40${\times}$40cm, with 4 kinds of seedling number per hill, 1,3,5 and 7, respectively. High photosynthetic efficiency (Eu) exhibited at the Samgangbyeo compared to Nakdongbyeo regardless of plant spacings and seedling numbers. For Samgangbyeo, Eu value was the highest at the 20${\times}$20cm plant spacing and five seedlings and seven seedlings per hill showed high Eu values at 10${\times}$10cm plant spacing and 20${\times}$20cm plant spacing, respectively, while other plant spacings were not significantly differed among seedling numbers. For Nakdongbyeo, however, one seedling plot obtained high Eu value at the 10${\times}$10cm plant spacing while this Eu value increased as the seedling number per hill increased in other plant spacings. There was a high positive correlation between rice grain yield and total competition index for both cultivars while kind of relationships differed in these two cultivars; linear relationship for Samgangbyeo and exponential relationship for Nakdongbyeo, respectively. Competition index between rice hill was more significant than within rice hill for Samgangbyeo while both competition indexs were important for Nakdongbyeo to increase rice yield.

• Journal of information and communication convergence engineering
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• v.7 no.3
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• pp.258-262
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• 2009

A Practical application of environmental monitoring system based on wireless sensor node network with the core of embedded system STR711FR2 microprocessor is presented in the paper. The adaptable and classifiable wireless sensor node network is used to achieve the data acquisition and multi-hop wireless communication of parameters of the monitoring base station environment including repeaters. The structure of the system is proposed and the hardware architecture of the system is designed, and the system operating procedures is proposed. As a result of field test, designed hardware platform operated with 50kbps bit rate and 5MHz channel spacing at 2040Hz. The wireless monitoring system can be managed and swiftly retreated without support of base station environmental monitoring.

• Korean Journal of Weed Science
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• v.1 no.1
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• pp.44-51
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• 1981

An experiment was conducted to obtain the basic information about competitive ability of rice against weeds as affected by culm length at the Yeongnam Crop Experiment Station, Office of Rural Development in 1980. More weeds were harvested from the plot of short statured cultivar, Manseogbyeo compared to the plot of Cheongcheongbyeo that was approximately 10cm taller than Manseogbyeo regardless of planting density variables. Weeds also decreased as rice population increased from $30{\times}15cm$, $40{\times}(10{\times}10cm)$ and to $10{\times}10cm$, in order. The degree of weed suppression and floristic composition was varied depending upon plant spacing and weeding regime subjected at the previous year. The degree of weed suppression became increased with increasing rice population. The degree of weed suppression at the $10{\times}10cm$ plant spacing showed as high as hand weeding subjected in the previous year. However, in terms of floristic composition, Scirpus hotarui Roxb. became dominant when rice had cultivated at $10{\times}10cm$ plant spacing in the previous year while S. hotarui and Sagittaria pygmaea Miq. were both important in the hand weeding plot. The highest grain yield of rice showed at the $10{\times}10cm$ plant spacing while no significant difference was observed between $40{\times}(10{\times}10cm)$ and $30{\times}15cm$ plant spacings for both weeding regimes and both cultivars. However, response of grain yield to weeding regime was differed in two cultivars. For Manseobgyeo, significant grain yield decreased in no weeding plot regardless of plant spacing variables. But in case of Cheongcheongbyeo, grain yield reduction was only recognized at the $30{\times}15cm$ plant spacing. Based on these result it could be concluded that Cheongcheongbyeo (10cm taller in height) seemed to be more competitive against weeds than Manseogbyeo.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.6D
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• pp.931-936
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• 2008

Surveying by using terrestrial LiDAR(Light Detection And Ranging) is more rapid than by using total station which enables tunnel section profile surveying to be done in suitable time and minimize centerline error, occurrence of overcut and undercut. Therefore, utilization of terrestrial LiDAR has increased more and more in section profile survey and measurement field Moreover, studies of terrestrial LiDAR for accurate and efficient utilization is now ongoing vigorously. Average end area formula, which was generally used to calculate overcut and undercut, was compared with existing methods such as total station survey and photogrammetry. However, there are no criteria of spacing distance for calculating overcut and undercut through terrestrial LiDAR surveying which can acquire 3D information of whole tunnel. This research performed reverse engineering to decide optimal spacing distance when surveying tunnel section profile by comparing whole tunnel volume and tunnel volume in difference spacing distance. This result was utilized to produce CAD drawing for the test tunnel site where there is no design drawings. In addition to this, efficiency of LiDAR and accuracy of CAD drawing was compared with targetless total station surveying of tunnel section profile. Finally, error analysis of target coordinate's accuracy and incidence angle was done in order to verify the accuracy of terrestrial LiDAR technology.

• Korean Journal of Medicinal Crop Science
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• v.3 no.2
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• pp.135-139
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• 1995

In order to determine the optimum planting density of Perilla frutescens which is suitable for the southern part of Korea, agronomic characters, yield of fresh stem, leaf and seed, and yield components were investigated grown in 1985 and 1986 at Mokpo Branch Station of Crop Experiment Station. The heading date was Aug. $14{\sim}15$ and the blooming period was Aug. $19{\sim}21$ regardless of the difference of plant density, but the longest stem length was 135cm in the plant density of $70{\time}40cm$ and the stem length in the plant density of $80{\time}40cm$ was 134cm. The quantity of fresh weight of stem and leaf and fresh weight of seed was high as 531kg/l0a in the plant density of $80{\time}40cm$. The positive correlation such as $0.7315^*,\;0.9024^{**}\;and\;0.7425^*$ were found between stem length and fresh weight of stem and leaf, stem length and fresh weight of seed, fresh weight of stem and leaf and fresh weight of seed and so high significance was recongnized. In the verification of significance of row spacing, the disperse of the stem length was $55.67^{**}$, that of fresh weight of stem and leaf is $268.50^*$, theat of fresh weight of seed was $16.00^{**}$ and high significance was recognized. In the verification of significance of intrarow spacing, the diperse of stem length was $54.21^{**}$, that of fresh weight of stem and leaf was $2,582.00^{**}$, that of fresh weight of seed was $48.00^{**}$ and then high significance was recognized. Accordingly, the proper plant density of perilla frutescens was 80cm of row $spacing{\time}40cm$ of intrarow spacing.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.41 no.9
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• pp.1085-1094
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• 1992

A variable-spacing cesium thermionic energy conversion test station is designed and fabricated for the study of power generation. The diode is in the form of a guard-ringed plane-parallel geometry in which a polycrystalline rhenium emitter of 2 cmS02T area faces a radiation-cooled polycrystalline rhenium collector of 1.9 cmS02T area. The emission of plasma from heated refractory electrode metal is the driving reaction in the direct conversion of heat to electricity by thermionic energy conversion. The plasma is produced from electrons and positive ions formed simultaneously by thermionic emission and surface ionization of cesium atoms incident on the hot emitter from the cesium vapor in the diode. And high plasma density causes plasma multiplication within the gap due to volume ionization that results in high power output. The variation of the saturation current of a Knudsen converter is investigated at an emitter-collector gap of 0.1 mm and an emitter temperatures. A maximum power output of 13.47 watta/cmS02T is observed at a collector temperature of 963 K and a cesium reservoir temperature of 603 K.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.2
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• pp.127-133
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• 1989

An experiment was conducted at the Yeongnam Crop Experiment Station to obtain basic informations about cultural techniques for high yield by manipulating plant spacing in association with seedling number. Cultivars showing relatively low competition index within or between rice hill were Palgongbyeo, Milyang 83. Milyang 90 and Sangpungbyeo, while those with high competition index were Pungsanbyeo, Samgangbyeo, Weongpungbyeo, Taebaegbyeo and Dongjinbyeo. Variations of agronomic characters such as culm length, spikelets per panicle, grain yield per panicle among each culm within hill were not interrelated among the characters. This phenomenon was also same within and between cultivar groups. However, cultivars having high competitive ability showed relatively low variation in agronomic characters. There was a trend that most of rice cultivars had a high positive correlation between total competition index and rice grain yield. Competition index between rice hill was more significant than that of within rice hill for Tongil type cultivars except Milyang 83 which belonged to low tillering capacity while both types of competition index within and between hill were important for Japonica type cultivars and Milyang 83 of Tongil type cultivar to increase rice yield.

• 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.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.7
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• pp.986-991
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• 2002

An experiment was conducted at Suwanvajokkasikit Research Station, Pakchong, Nakornratchasima, Thailand, to determine the yield and quality of three different grass cultivars intercropped with leucaena (Leucaena leucocephala). The treatments consisted of three grass cultivars (ruzi, dwarf napier and Taiwan A25) as the main plots, planted between leucaena at three row spacings (1, 2 and 4 m width) as the sub plots and leucaena cutting height (10 and 25 cm above ground levels) as sub-sub-plots. Dwarf napier consistently produced more dry matter than Taiwan A25 or ruzi and Taiwan A25 outyielded ruzi. Leucaena yield was highest in the ruzi plot and lowest in the dwarf napier plot. However, yields of grass plus leucaena were highest in the dwarf napier plot and were lowest in the ruzi plots. The difference was due mainly to the grass components. Increasing the spacing between rows of leucaena resulted in a lower leucaena yield but the reverse was true for the grasses. Cutting of leucaena at 10 cm above ground levels depressed yields of leucaena but did not affect the associated grasses. In terms of herbage quality, it was found that the crude protein of leaves and stems of the dwarf napier and Taiwan A25 were higher than that of the ruzi grass. Leucaena gave higher levels of crude protein than all grasses. The phosphorus and potassium levels of all grasses were higher than leucaena. ADF levels were higher in the grasses than in the legumes. Nutrient contents in the leaves and stems of grasses and leucaena were not affected by leucaena spacing and cutting height.

• Journal of Bio-Environment Control
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• v.22 no.3
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• pp.256-261
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• 2013

The spacing between plug cells and cell volume of each plug cell for nursing tomato seedlings were studied to know the effects on seedling growth and early yield. There were four treatments. The spacing of plug cells was done (OK) or not (NO) in case of cell spacing. The cell number in a plug tray was set to 40 or 50 in case of cell volume. The growth environment and irrigation regime were the same in all of the treatments during the experiment period. The photosynthetic rates, seedling qualities, yield and yield speed were significantly affected by both of the treatments. The photosynthetic rates and seedling qualities were the best in 40S-OK following by 50S-OK, 40S-NO, and 50S-NO while the yield was the best in 40S-OK following by 40S-NO, 50S-OK, 50S-NO. It means the spacing gives more impact than the cell volume in the stage of nursing but the cell volume gives more impact than the spacing after the stage of nursing. In the conclusion the spacing of plug cells in appropriate nursing stage is needed with the appropriate cell volume to make high quality of seedlings and high yield.