• Journal of Biosystems Engineering
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• v.4 no.2
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• pp.9-9
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• 1979

It is understood that drum speed of threshers and the moisture content of paddy grains to be threshed, respectively, have a signific:mt effect upon rice recoveries. Threshing under an increased drum speed would give a high performance rate, which is the general practice in custom work threshing in association with the use of semiauto-t hreshers. In the connection, however, it may result in the promotion of grain cracks and brokens of the rice product after milling. No reference or determination for an opti mum drum speed of the thresher is made available for various grain moisture contents at the time of the threshing operation and for different rice varieties especially for the Tongil rice varieties. This study was Conducted to find out and determine effects of the drum speeds on grain losses. The grain loss was quantified in terms of recovery rates of rice grains after treatments. Samples of each of all treatments were taken from the grain sampling plate placed in the grain conveyor of threshers. The grain sample plate was specially provided for this experiment. The brown-rice, milling, and head-rice recJveries were tes ted in the laboratory mill, respectively. Two rice varieties, Akibare and Suweon 251, each with five levels of different moist?ure contents at harvest and six levels of different drum speeds of threshers, were selected and used for treatments in this experiment. Two conditions of materials were tested in the thresher. One condition was to thresh the experimental material immediately after cutting, referred to as the wet-material thr eshing in this study. The other was to thresh the experimental :material, dried to contain about 15-16 percent of the grain moisture under the shocking operation. This is referred to as the dry-material threshing in this study. In additioon, field measurements for the grain moistures and drum-sdeeds under actual operation practices of the traditional field threshing, were conducted with a view to comparing with results of the experimental treatments. The results of the study may be summarized as follows: 1. For threshing treatments of Japonica-type rice variety (Akibare) , the effect of drum speeds and levels of grain moisture at cutting upon brown-rice, milling, and head-rice recoveries were found statistically significant. No significant difference in these recovery rates was noticed regardless of whether the material was threshed right after cutting or after drying by the shocking operation. 2. For the Tongil-sister rice variety(Suweon 251), milling recovery for the varied drum-speed and the grain~moisture level at cutting was found statististically significant. Th milling recovery was much significant when associated with the wet-material thres?hing compared to the dry-material threshing. 3. The optimum peripheral velocity to be maintained at the edge of teeth on the thr?esher drum was determined and may be recommanded as that of about 12 to 13 meters per second in view of the maximum recovery rate of the milled rice. 4. The effect of the drum speed on the qualitative loss of the milled rice was much greater in the case of the Tongil variety than Japonica. This effect was also greater by the wet-material threshing than by the dry-material threshing. Therefore, to apply the wet-material threshing operation for the Tongil variety, in particular, it should be very important to introduce the kind of threshing technology which would maintain the drum speed at optimum. 5. A field survey for the actual drum speed of threshing operations for 50 threshers indicated that average peripheral velccity was 12.76m/sec., and that the range was from 10.50 to 14.90m/sec. Approximately, more than 30% of the experimented and measured threshers were being operated at speeds which exceeded the optimum speed determined and assessed in this study. Accordingly, it should be highly desirable and important to take counter-measures against these threshing practices of operational overspeed.

• Science of Emotion and Sensibility
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• v.21 no.3
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• pp.141-150
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• 2018

The purpose of this study is to investigate three-dimensional embroidery techniques for creating conductive fabric materials. Such techniques can increase the efficiency of energy harvesting by increasing the fabric's area during rubbing and brushing. We also investigate the fabric structure of the triboelectric energy harvesting type. Two experiments were conducted for this purpose. In Experiment I, the three-dimensional embroidery technique(satin technique, file technique) and the conductive fabric material(copper-based MPF, nickel-based MPF) were selected as the main variables affecting the efficiency of triboelectric energy harvesting from the human body. Four samples were fabricated according to a combination of two variables. In Experiment II, the harvesters fabricated by the three-dimensional embroidery method showing the highest efficiency were subjected to brushing processes and the voltages generated after processing were analyzed. As a result, in both conductive fabric materials, the pile embroidery fabric structure showed a higher efficiency than the satin structure. These results show the triboelectric energy harvesting principle, which is proportional to the charge density and the generated voltage. It can be seen that the structure of pile embroidery fabric with a large friction area is advantageous for increasing efficiency compared to satin embroidery-fabric structure with a relatively small friction area. Moreover, the energy harvesting efficiency after brushing was higher than that before processing due to the increased friction area, and it was found that the brushing method is advantageous for increasing the triboelectric-energy harvest.

• Journal of Korean Society of Forest Science
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• v.61 no.1
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• pp.60-68
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• 1983

Ever since the day of pre-modernized society where the farming skill had been in the stagnant condition, the common farmwoodlands have been utilized in common (collectivelly) by villagers in order to harvest farmwoodlands and fuelwoods. Later, during the process of modernization, most of the common farmwoodlands were transferred into national or public forests by the administrative enforcement, but there were still various types of village (common) forests such as the common forests owned by joint owners, village block associations, village forest productive societies, Village Forestry Association(V.F.A.), and the national or public forests leased to V.F.A. As Village Forestry Association is organized with a few villages, each of common forests ow nod to the villages is obliged to be diversely controlled by other managers than the chief of V.F.A. Therefore, it is to be desired that the control of common forests should be under Gun Forestry Association Union. While the rate of the use of common forests for fuelwoods and cemetery has been considerably high, villagers wish to promote the timber forest establishment through the collective management by their improved farming skills and economical situations. In these present circumstances the village forest productive societies should be guided to work in closer cooperation with Gun Forestry Association Union. Since the management of common forests is still extensive, it still remains in the semi-management condition under which we can not find any management plan or measure to control forest damage. Especially the small area common forests should have appropriate size for the joint management. This will promote the forest productivity through the lease for reforestation of disposable national forests or public county forests and the contracts for profit sharing. Today owing to increasing forest value, frequent dispute has occurred on the common right telated to the village forests and rationalization of forest management has been disregarded. If a necessary measure were taken to control the dispute such as transferring the registeration right of ownership to the village forest productive society, the confidence of local inhabitants can be regained and the productivity of forests can be naturally increased.

• The Korean Journal of Pesticide Science
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• v.8 no.4
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• pp.299-308
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• 2004

In order to elucidate the behavior of bensulfuron-methyl, a sulfonylurea herbicide, in a soil/plant microecosystem, rice plants (Oryza sativa L.) were grown for 12 weeks in the specially made stainless steel pots (17cm I.D. $\times$ 10cm H.) containing two different paddy soils treated with fresh and 13-week-aged residues of [phenyl-$^{14}C$]bensulfuron-methyl, respectively. During the aging period, the mineralization to $^{14}CO_2$ from soil A (OM, 3.59%; CEC, 7.65 $cmol^+\;kg^{-1}$; texture, sandy clay loam) and B (OM, 1.62%; CEC, 4.51 $cmol^+\;kg^{-1}$; texture, sandy loam) amounted to 6.79 and 10.15% of the originally applied $[^{14}C]$bensulfuron-methyl, respectively. The amounts of $^{14}CO_2$ evolved from the soils with fresh residues were higher than those from the soils with aged residues. At harvest after 12-week growing, $^{14}C$-radioactivity absorbed and translocated into rice plants from soils A and B containing fresh residues of bensulfuron-methyl was 1.53 and 4.40%, while 4.04 and 6.37% in the two soils containing aged residues, respectively. Irrespective of aging and soil type, the $^{14}C$-radioactivity remaining in soil ranged from 80.41 to 98.87% of the originally applied $[^{14}C]$bensulfuron-methyl. The solvent extractability of tile soils was $39.25\sim70.39%$, showing the big differences among the treatments. Most of the nonextractable soil-bound residues of $[^{14}C]$bensulfuron-methyl were incorporated into the fulvic acid fraction$(61.32\sim76.45%)$. Comparing the microbial activity of the soils with rice plants grown with that of the soils without them, the former was $1.6\sim3.0$ times higher than the latter. However, it did not correlate with the $^{14}CO_2$ evolution.

• Journal of Food Hygiene and Safety
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• v.24 no.4
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• pp.299-306
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• 2009

Aflatoxin (AF) and Ochratoxin A (OTA) are carcinogenic and possible carcinogenic mycotoxins respectively produced by Aspergillus spp or Penicillium spp. The study for contamination survey and proposal for reduction of mycotoxin in red pepper were carried out. 192 samples were collected at such various stages and markets as pre/post-harvest stages, internet shopping mall /super-market and small stakeholder mill/geographically indicated company. As only 2 samples were positive for aflatoxin, so contamination rate was 1.04%. In the meanwhile, contamination rate for ochratoxin A was 21.88% and a various amount of OTA was detected in 42 positive samples. 6 samples were found to be contaminated at higher level than $5\;{\mu}gkg^{-1}$ for ochratoxin A, which was established recently as a maximum permissible limit in korea. There was no difference in degree of contamination with regard to cultivation type because any mycotoxin was not found at all in both organically and conventionally grown red pepper. But, there was statistically significant difference in the process of manufacturing. Finished products were OTA-contaminated at a level of $2.32\;{\pm}\;6.54\;{\mu}gkg^{-1}$(mean ${\pm}$ SD), even though OTA was not detected in deep frozen red peppers right after long term storage. And contamination for OTA was a level of $0.33\;{\pm}\;0.91\;{\mu}gkg^{-1}$(mean ${\pm}$ SD) in red paprika powder after uv sterilization, while the contamination for OTA was $2.78\;{\pm}\;4.49\;{\mu}kg^{-1}$(mean ${\pm}$ SD) in non-uv sterilized powder. In addition, our investigation shows that higher OTA contamination occurred in some of famous brand products sold in super-market and domestic products than products collected through on-line shopping or from small stakeholder mills and imported products respectively, however, difference was not statistically significant.

• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.4
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• pp.307-312
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• 2009

This experiment was conducted to compare the agronomic characteristics and productivity of induced annual legumes at paddy field of Cheonan and Naju from 2004 to 2006. Chinese milk vetch (wild type), crimson clover (C.V. Linkarus), forage pea (C.V. Austrian pea), hairy vetch (C.V. Oregon commen) were used in this study. At the Naju region, the earliest flowering on 2nd may was found in Chinese milk vetch, while the latest on 18th May in forage pea. Fresh, dry matter (DM) and crude protein (CP) yields of crimson clover were highest as 28,870, 6,986 and 943 kg/ha, respectively. but the yield of chinese milk vetch was low by 9,885, 1,749 and 338 kg/ha. At the Cheonan region, the most fast flowering date variety was Chinese milk vetch, hairy vetch was very late as 19th May. Fresh, DM and CP yields of hairy vetch were highest as 7,916, 1,141 and 113 kg/ha, respectively. but the yield of chinese milk vetch showed the lowest by 270, 42 and 8 kg/ha. The CP content of annual legumes was 14.3%. chinese milk vetch showed the highest CP content by 19.3% and hairy vetch showed the lowest content by 9.9%. The present data showed that the productivity was closely dependent on winter hardness, in conclusion, crimson clover at Naju and hairy vetch at Cheonan region was suggested to be the most proper species as winter crop after rice harvest on paddy field when considered the winter hardiness.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.5
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• pp.535-548
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• 1994

Community structures and fish densit were investigated on three different types of artificial reefs, dice, turtle artificial reef and tubes, constructed in the Korean waters. Variations of fish fauna according to type of artificial reef and the proper artificial reef in each area for optimizing harvest were discussed. Fish were captured by trammel gill net during May, June, September and November, 1988 and both identified and counted. Fourty-five fish species were found in the artificial reefs. Of these, Sebastes spp., Hexagrammos otakii, Pleuronectidae, Navodon modestus and Stephanolepis cirrhifer showed high occurrence-frequency. The dominant species groups were coastal settlement, demersal or rock fishes such as Pleuronectidae, Rajiformes, Stephanolepis cirrhifer, Navodon modestus, Hexagrammos otakii and Sebastes spp. in all of the Artificial reefs except the oceanic area of southern waters. Scomber japonicus was predominant in the oceanic area of southern waters. Composition of demersal, rock and pelagic fishes were different depending on the types of artificial reef. Dice artificial reefs were occupied by rock fish, on the other hand turtle artificial reefs were dominated by dermersal fish. Fish density was high at the dice artificial reef in all survey areas except the middle area of Eastern waters, with high fish density evident in the Tube artificial reef. Fish community structures were remarkably different between Dice and Turtle artificial reefs. The Tube artificial reef showed intermediate characteristics between the above two types of artificial reefs. The coastal areas of Southern waters and the middle and southern areas of Western waters revealed similar fish fauna. Results from the oceanic areas of Southern waters were well associated with the middle and southern areas of Eastern waters.

• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.3
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• pp.261-268
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• 2011

This study was carried out to determine the forage production and quality of Italian ryegrass (IRG) and forage barley developed by Korea in Suwon, 2009~'10. The nine treatments were two IRG varieties (Kowinearly with early maturity and Kowinmaster with medium maturity), five barley varieties (Youngyang, Wooho, Yuyeon, Dami and Youho), and two mixtures (Kowinearly + Yuyeon and Kowinmaster + Yuyeon). The heading dates of Kowinearly and Kowinmaster were 14 May and 18 May, respectively. The growth stage of barley investigated at 22 May were late milk in Youngyang and Wooho, early dough in Dami and early to medium dough in Yuyeon and Youho. Plant length of IRG in IRG + barley mixtures was 117~118 cm, which was longer than those of IRG monoculture of 98~101 cm, and no lodging was found in mixtures. The dry matter (DM) percentage at harvest was 20.7~25.4% in all treatments. The botanical composition of IRG in mixtures was 43.1%. The percentage of spike per barley plant was become high according to progressed maturity, as a 35.7%, 44.1%, 54.8% and 57.2% in late milk, dough, yellowish and full ripeness stage, respectively, and the spike percentages of Youngyang and Wooho were tends to high. The crude protein (CP) content of IRG as 9.0~10.0% was higher than that of barley (7.0~8.5%), and the contents of NDF and ADF of barley were lower than those of IRG, and in vitro DM digestibility were 64.4% in Kowinearly, 64.1% in Kowinmaster, 64.5% in mixture, and 60.2% (Youho) to 66.4% (Wooho) in barley. The yields of DM, CP and in vitro digestible DM were high in Kowinmaster+barley mixture as a 11,508 kg, 1,046 kg and 7,422 kg per ha, respectively (p<0.05). However, no significant differences in forage yield were observed among cultivar of IRG, and barley, although Wooho was tends to high in digestibility and forage yield among five barley varieties. In conclusion, the mixture cultivation of IRG Kowinmaster + forage barley was recommended, because of preventing of IRG lodging, higher plant length of IRG, increasing of forage yield, and stable production. Selection of suitable winter forage species and variety for district, climate environment, and utilization type of farm was also important.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.29 no.3
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• pp.22-32
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• 2011

This study explored the architectural nature, the thought reflected in the place and the 'meaning-landscape' characteristic of a place, to where a retired scholar had lived. The object of the study is the Maechun-Byulup Toesu-jeong wonlim, which consists of a summer house and a garden forest. The results of the study are as following. Toesu-jeong wonlim is located at Daejeong-ri, Sannae-myeon, Namwon-si. It had been built by Maechun Park Chi-Gi in 1870 for his residence after retirement. It is a villa type pavilion and a garden forest which have Banseondaegi(伴仙臺記), Banseondae-10-yeong, Toesu-jeong(退修亭) Sangryangmun, a writing dedicated when putting up the ridge beam of a wooden house), Toesu-jeong Wonwun Byeongsoseo, hanging boards and tablets with poems written on them. In the Toesu-jeong wonlim, there are various 'meaning-landscapes' such as the Maechun-Byulup, Banseondae, Yabakdam and Simjinam together with engraved calligraphy related to the landscaping culture. It is also possible to find the remains of beautiful engraving on the stones and woods at Goksoo Yoogeo(曲水流渠) that suggest the banquets they had while discussing the elegant tastes and appreciating the landscape. The Toesu-jeong wonlim consists of the Toesu-jeong area(a pavilion), the Gwanseon-jae area(a shrine) area and the Gyejeong area(a garden with a brook) area. The pedantic 'meaning-landscape' elements, as the residence of retired scholar who spent his remaining life with elegant tastes, and the expertise of Maechun Park Chi-Gi, as a landscaping architect who built a villa and a garden forest in the motif of a Taoist hermit, can be extracted through the Banseondae-10yeong. The Banseondae-10yeong is the first Toesu-jeong poem and consisting of the Samseon-dae, Sejin-dae, Samcheong-dam, Yabak-dam, Samseo, Takgeum-dam, flat stones, caves, stone sculptures and harvest. The existing vegetation and plants in the Toesu-jeong wonlim are; natural pine forest in the rear garden, zelkova trees, wild cherry trees, apricot trees and pine trees bent to the waterfront direction. Except some ornament-species and shielding-species such as the poplars, most of current trees and vegetation keep the shape of the original Toesu-jeong wonlim landscape.

• Journal of Bio-Environment Control
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• v.31 no.1
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• pp.28-34
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• 2022

This study was conducted to determine the changes in ginsenosides content according to additional UV-A, and UV-B LED irradiation before harvesting the ginseng sprouts. One-year-old ginseng seedlings (n=100) were transplanted in a tray containing a ginseng medium. The ginseng sprouts were grown for 37 days at a temperature of 20℃ (24h), a humidity of 70%, and an average light intensity of 80 µmol·m^-2·s^-1 (photoperiod; 24h) in a container-type plant factory. Ginseng sprouts were then transferred to a custom chamber equipped with UV-A (370 nm; 12.90 W·m^-2) and UV-B (300 nm; 0.31 W·m^-2) LEDs and treated for 3 days. Growth parameters and ginsenoside contents in shoot and root were conducted by harvesting on days 0 (control), 1, 2, and 3 of UV treatments, respectively. The growth parameters showed non-significant differences between the control and the UV treatments (wavelengths or the number of days). Ginsenoside contents of the shoot was highly improved by 186% in UV-A treatment compared to the control in 3 days of the treatment time. The ginsenoside contents of the roots was more improved in UV-A 1-day treatment and UV-B 3-day treatment, compared to the control by 171% and 160%, respectively. As a result of this experiment, it is thought that UV LED irradiation before harvesting can produce sprout ginseng with high ginsenoside contents in a plant factory.