• Korean Journal of Weed Science
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• v.7 no.1
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• pp.52-57
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• 1987

To know the effects of weeding periods (weeding from 12 days, 28 days and 42 days after seeding to harvest, and weeding from seeding to 14 days, 28 days and 42 days after seeding) and growing conditions such as transparent polyethylene film mulch (P.E. mulch) and bare soil on growth and yield of peanuts, "Yeongho-Tangkong" was planted on May 10, 1984. Under P.E. mulch, the number of weeds was higher, but the weed dry weight was lower than in bare soil by the middle of July. Sixty days after seedings, the length of main stems in weedy check plots was longer, but shoot dry weight was lower compared to weed free plot. In the correlation coefficients between weed dry weight and the shoot dry weight of peanut on July 14, the growth retardation of peanuts due to weeds was showed earlier under P.E. mulch than in bare soil. Shoot dry weight, shelling ratio, number of seeds per pod, 100 pod weight, and seed yield were higher under P.E, mulch compared to bare soil. But weed dry weight, length of branches, number of pod bearing branches, number of pods per square meters, and pod yield were similar between P.E. mulch and bare soil. Shoot dry weight of peanuts, length of branches, number of pod bearing branches, number of pods per square meters, pod yield, 100 pod weight, 100 seed weight, and seed yield in weed free plots from 28 days after seeding to harvest (28 DAS-Harvest) were higher compared to weed free plots from 42 DAS-Harvest. However, in the weed free plot from seeding to 42 days after seeding seed yield was lower than that of the continuous weeding plot due to lower number of pod bearing branches and number of pods per square meters. When weed was not controlled at the later growth stages of peanuts, reduction in seed yield due to weeds was greater in bare soil than that under P.E. mulch.

• Korean Journal of Weed Science
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• v.7 no.2
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• pp.236-242
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• 1987

The study was conducted to interprete the fluctuation of weed vegetation in plant-sociological impacts as affected by the mixture use of oxyfluorfen and glyphosate with various dosages. Also, intended to know the real interaction between two herbicides in weeding efficacies. The better efficacy from the above mixture was recognized than from the oxyfluorfen + paraquat mixture on the perennial-sites. In lower rate mixture of oxyfluorfen, the dominance index was increased by the annual grass species (ie. Digitaria), and of glyphosate by the biennial Stellaria and perennial species (ie. Artemisia). Also, the positive maximum action of both oxyfluorfen and glyphosate in various mixture rates was categorized upto 0.55kg ai/ha for oxyfluorfen and 0.35kg ai/ha for glyphosate, respectively. However, the interaction between the above two herbicides recognized actually as negative. Consequently, the use of mixture compound of oxyfluorfen with glyphosate are expected rather to promote the control efficacy of specific weed species, to enlarge the weeding spectrum and to prolong the weeding periods than to reduce the application rate of both chemicals depending on any synergic interactions.

• Korean Journal of Weed Science
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• v.16 no.1
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• pp.72-75
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• 1996

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1998.12a
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• pp.69-75
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• 1998

• Korean Journal of Organic Agriculture
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• v.6 no.2
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• pp.127-140
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• 1998

Organic farming excludes any use of the herbicide. The present paper reviews what can be done for effective weed control with existing weed control technology by farmers crop-ping paddy rice, field crops, vegetables, and fruit trees. If condition of the crop-land-al-lows diversified rotational use of the paddy land as paddy and upland field would minimize weed problem. Practising this is limited in acreage due to extremely limited governmental investment to the land for the purpose. Secondly, rotation of crops in the upland field breaking life cycles of various weeds adapted to each crop should reduce the weed problem. This is also limited as only a few crops are making the farmer profitable. In addition climate and tolerance of crops to high and low temperature. Monsoon rains and poor drainage restrict the freedom of choice. For any crop land year-round multiple cropping in denser planting shall lessen the weed problem, this multiple cropping practiced by 1960s has been abandoned due to laborshortage and increased production cost. Deep flooding the rice is impractical at present in Korean. Mulching crop with transparent, black , or combinated polyethylene sheet, hs been in-creasingly used. Progresses in development and use of mulch with allelopathic crop residues. inexpensive paper mulch, allelopathic crop residues, inexpensive paper mulch, allelopathic crop cultivar development, recently developed ex-perimental weeding machinaries, flamers, microbial herbicides, biological control organisms, soil sterilization techniques have been critically reviewed for their adoption into existing in-tegrated weeding system. Unfortunately, information on cost-benifit, and labor-benefit, for the various methods above mentioned are lacking. Urgent need for the research on rational weeding in organic farming, and herbicide low-input farming is emphasized.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.2
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• pp.169-175
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• 2007

This experiment was carried out to compare weed occurrence and to evaluate the field performance of some leguminous plant species under no-weeding fallow condition during summer months from middle of June to middle of August. In 2005 and 2006, the first dominant weed species was Digitaria sanguinalis, and other major weed species, such as Cyperus amuricus, Portulaca oleracea, and Amaranthus retroflexus, were similar among treatments. In both years, total shoot dry weight of weeds was the highest In the control plot, and the lowest in the cowpea plot, indicating that cowpea most effectively suppressed the growth of weeds among treatments. When the growth of four different leguminous species were compared after seeding during middle of June in 2006, cowpea and rice bean grew vigorously under no-weeding condition during hot and humid summer months, while wild soybean and hairy vetch did not. Shoot dry weight was in the order of cowpea > rice bean > wild soybean > hairy vetch. In conclusion, cowpea is a leguminous species which can be used as a green manure cover crop during summer months under no-weeding and our climate condition. Further works are needed to use cowpea as a green cover crop during summer months for various cropping systems.

• The Journal of Korea Robotics Society
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• v.9 no.3
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• pp.147-153
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• 2014

In this paper, we proposed a new algorithm of the guidance line extraction for autonomous weeding robot based on infrared vision sensor in wet paddy. It is the critical process for guidance line extraction which finds the central point or area of rice row. In order to improve accuracy of the guidance line, we are trying to use the morphological characteristics of rice that the direction of rice leaves have convergence to central area of rice row. Using Hough transform, we were represented the curved leaves as a combination of segmented straight lines on binary image that has been skeletonized and segmented object. A slope of the guidance line was gotten as calculate the average slope of all segmented lines. An initial point of the guidance line was determined that is the maximum pixel value of the accumulated white columns of a binary image which is rotated the slope of guidance line in the opposite direction. We also have verified an accuracy of the proposed algorithm by experiments in the real wet paddy.

• The Plant Pathology Journal
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• v.19 no.2
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• pp.92-96
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• 2003

The study was conducted to determine the cultural conditions and the effect of inert fillers for melanization and sporulation abilities of sodium alginate pellets, and the weeding efficacy of the formula in the field. Melanin production of E. nematosporus was affected by striking frequency. Percentage of melanized beads was increased to 80.6% at higher rpm up to 180. The melanized pellets produced more conidia with abundant mucilage than unmelanized pellets. Shaker culture of Epicoccosorus nematosporus with sodium alginate yielded a total of 55 mg per 100 pellets. Percentage of melanized pellets was highest with 81.0% and 83.3% of melanization, when wheat bran and rice polish were amended and produced the conidia with 65.4 and 68.4 mg per 100 pellets, respectively. When 1 L of conidial suspension of 6.0$\times$$10^5$ conidia per ml was applied on 30-day-old plants in a plot, 74.5% of the plants were killed within 20 days, whereas, its melanized sodium alginate pellets killed 57.8% of the plants in the same period. The number of tuber formation of Eleocharis kuroguwai in the untreated control plots was 128.5 per plot, but those of the plots treated with conidial suspension and melanized pellets were 22.1 and 39.7, respectively, at the end of the season. Results of this study showed that melanization of mycelia-mixed sodium alginate are an important sporulation factor in E. namatosporus as a mycoherbicide.

• 보존과학연구
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• s.24
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• pp.187-213
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• 2003

Sungseonsa Temple site in Chungju city in Chungcheongbuk-doProvince is written in "Goryeosa" as a building for Queen Sinmyeongsunseong, the mother of Gwangjong in AD 954 in Goryeo Dynasty. The museum in Chungcheong University takes charge of the excavation for 3 times from 2000 to 2002 and identified that its construction was carried out till Joseon Dynasty. Among the iron artifacts from the first excavation such as a weeding hoe, a hand knife, a lock, two nails and a plow which had conservation treatments, the sample was collected. Its micro-structure and method of manufacture were investigated. Excavation report for those artifacts has not published yet, therefore, the date of each artifacts is not clearly confirmed. The samples were collected from each part of the objects and then embedded in epoxy resin and etched with nitric acid. The examination of its microstructure is carried out under the microscope and the hardness values were measured by Vickers hardness tester. From the results, some artifacts show different manufacture method sin the each parts. The forming processes of the iron weeding hoe and the iron sickle are similar but the blade of iron weeding hoe was strengthened by carbonization whereas the blade of the iron sickle was done by quenching. The hand knife and the nails were produced through almost same methods and shows similar microstructures. The hand knife seems to be made by repeated beating and folding in low temperature resulting in fine crystallization, but the nail shows large crystallization due to processes in high temperature. Lock is made of white cast iron, that does not show any heat treatment.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.13
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• pp.93-105
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• 1973

Differential tolerance of rice varieties, Tongil and Mangyung(or Milsung) varieties, against herbicides combined with Simetryne was investigated by the rate of application in 4 places; Jeonju, Gwangju, Iri and Milyang, whose soil textures were Lic, Sic, CL and Lic respectively. The results are summarized as follows: 1) Jeonju a. Initial crop injury At the rate of 2kg/10a prod. no initial crop injury was caused(both to Mangyung and Tongil varieties) on light clay soil, even when treated at high temperature of $30^{\circ}C$ and above. Crop injury was first caused at 3kg/l0a prod. to Tongil variety and the damage increased in proportion to the increase of application rate, while no crop injury was caused to Mangyung variety even at high rate of 5kg/l0a prod. b. Yield Tongil variety: Under high temperature condition in a vinyl house no statistical difference was observed between treated and hand weeding plot at the rates of 3kg/l0a prod. and below. Under air temperature conditions no statistical difference was observed between treated and hand weeding plot at the rates of 4kg/l0a prod. and below. Mangyung variety: No statistical difference was observed between treated and hand weeding plot at the rates of 5kg/l0a prod. and below both under air and high temperature conditions. 2) Gwangju a. Initial crop injury Although almost the same tendency as in Jeonju was observed, a little lighter crop injury was observed in general in Gwangju than in Jeonju at the time of application. And so, no crop injury was caused to Tongil variety until 4kg/l0a prod. and above. b. Yield Tongil variety: No statistical difference was observed between treated and hand weeding plot at 4kg/l0a prod. and below. Mangyung variety: No statistical difference was observed between treated and hand weeding plot at 4kg/l0a prod. and below. 3) Iri No crop injury was caused both to Tongil and Mangyung varieties at 4kg/l0a prod. and below. Also, no reduction of grain yield was observed. 4) Milyang A little lighter crop injury was observed in general. No crop injury was caused to Milsung variety at 5kg/l0a prod. ; Only a slight crop injury was caused to Tongil variety. Yield: No statistical difference was observed between treated and hand weeding plot both of Tongil and Milsung varieties even at 5kg/l0a prod. and below.