• 한국표면공학회지
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• 제53권5호
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• pp.241-248
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• 2020

The change of the deposition behavior of diamond through a pretreatment process of the base metal prior to diamond deposition using HFCVD was investigated. To improve the specific surface area of the base material, sanding was performed using sandblasting first, and chemical etching treatment was performed to further improve the uniform specific surface area. Chemical etching was performed by immersing the base material in HCl solutions with various etching time. Thereafter, seeding was performed by immersing the sanded and etched base material in a diamond seeding solution. Diamond deposition according to all pretreatment conditions was performed under the same conditions. Methane was used as the carbon source and hydrogen was used as the reaction gas. The most optimal conditions were found by analyzing the improvement of the specific surface area and uniformity, and the optimal diamond seeding solution concentration and immersion time were also obtained for the diamond particle seeding method. As a result, the sandblasted base material was immersed in 20% HCl for 60 minutes at 100 ℃ and chemically etched, and then immersed in a diamond seeding solution of 5 g/L and seeded using ultrasonic waves for 30 minutes. It was possible to obtain optimized economical diamond film growth rates.

• 한국초지조사료학회지
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• 제43권4호
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• pp.199-205
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• 2023

Pasture formation and management are crucial to avoid yield reduction. This experiment aimed to examine the effects of tall fescue-centered mixed-seeding combinations on yield and vegetation changes in perennial pastures in the central region for two years, from September 2020 to October 2022. The treatments were arranged in three replications in a randomized block design: control (C), tall fescue-based mixture-1 (T-1), and tall fescue-based mixture-2 (T-2). The tall fescue (TF), orchard grass (OG), perennial ryegrass (PRG), Kentucky bluegrass (KBG), and white clover (WC) were used. The emergency rate of grasses (70.0 to 73.3%) did not differ among mixed seeding combinations. Overwintering rates (81.7 to 83.3%) were similar among treatments. The plant height of grasses was similar at each harvest date, with the highest height (86.2 cm) recorded in the second harvest of the first year, followed by that (58.4 cm) in the third harvest of the first year; it was least (38.9 cm) in the fourth harvest of the second year. There was no significant difference in the dry matter yield of grasses among the mixed seeding combination treatments in the first, third, or fourth harvests of the first year (p>0.05). For second-year grasses, dry matter yield was not significantly different in harvest date among the treatments (p>0.05). Based on mixed seeding ratio, orchard grass showed the highest yield at 70% in the C treatment, followed by tall fescue at 80% and 60% in the T-1 and T-2 treatments, respectively, in the first harvest after seeding. There was no significant difference in feed value between treatments (p>0.05), but a significant difference was observed between the third and fourth harvest (p<0.05). Therefore, it indicated that it is important to create perennial pastures in the central region through mixed seeding combinations centered on tall fescue.

• 한국잡초학회지
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• 제30권3호
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• pp.252-257
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• 2010

뚝새풀의 친환경 관리법 개발을 위해 밀 파종 전 토양 로타리 경운을 추가하고 파종한 결과 뚝새풀 발생 수는 85%가 감소되었다. 잔여 뚝새풀의 발생밀도를 더 줄이기 위하여 밀 파종시기와 파종량에 따른 효과를 검토코자 밀 종자량 150kg $ha^{-1}$을 기준하여 시기를 달리하여 파종한 결과 10월 16일 파종시에는 뚝새풀 발생이 $m^2$ 당 40개가 발생하였으나 10월 26일 29개 11월 6일 파종시에는 4개로 밀 파종시기가 늦을수록 뚝새풀 발생이 감소되었다. 밀 파종량에 따른 영향은 10월 26일에 ha당 종자 150kg을 파종하였을 때는 $m^2$당 29개가 발생하였으나 파종량 200kg $ha^{-1}$ 이상에서는 8~11개로 감소되었다. 이상의 결과를 종합하면 남부지방에서 10월 하순경 밀 파종 전에 로타리를 이용하여 토양을 파쇄하고, 종자량을 ha당 200kg으로 증량하여 파종하면 제초제를 사용하지 않고도 뚝새풀을 비롯한 잡초에 의한 수량감소를 최소화 할 수 있을 것으로 판단된다.

• 한국작물학회지
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• 제58권3호
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• pp.319-323
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• 2013

앵미의 온도와 파종깊이 및 토양수분에 따른 발아와 유묘생육의 특성을 규명하기 위하여 앵미 2종과 대안벼를 공시하여 시험한 결과는 다음과 같다. 1. 저온조건에서 발아시험 결과 앵미가 대안벼보다 발아율이 높았고 발아속도도 빨랐으며 종자세가 우수하였다. 2. 저온조건에서는 수분함량이 많을수록 발아율이 높았고, 중온조건에서는 토양수분 45% 조건에서 발아율이 가장 높았다. 3. 영천앵미의 발아 특성은 파종심도 6 cm 처리구에서는 저온과 중온에서는 발아를 하지 않았으나 고온에서는 발아를 하였다. 4. 합천앵미와 영천앵미의 발아 특성중 영천앵미가 합천앵미보다 발아율 및 종자세가 우수한 것으로 나타났다.

• 한국작물학회지
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• 제44권2호
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• pp.97-101
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• 1999

No-till direct seeding cultivation of rice has major advantages such as saving of labor and cost by eliminating tillage, preparation of seed bed and trans-planting procedure compared to the conventional transplanting cultivation. A field experiment was conducted to evaluate the effects of straw treatment and nitrogen levels on the rice growth in no-till direct-seeding cultivation. Rice straw, vetch straw, and the mixture of both of the straws were mulched on the surface of soil before seeding while 4 levels of nitrogen fertilizer, 0, 7, 9, and 11 kkg/10a respectively, were applied at 3 split times, 3-weeks after sowing, 5-weeks after sowing and the panicle initiation stage. Mulching of vetch straw significantly reduced seedling establishment of rice which may be attributed to low oxidation-reduction potential of soil by vetch mulching treatment. Vetch straw increased the concentration of soil ammonium leading to an extension of the greenish leaf to panicle initiation stage. Agronomic nitrogen use efficiency (AD $E_{N}$) in heavy-mixed straw mulching plots was lower than other treatments. Grain yield and AU $E_{N}$ in the vetch treatment were less affected by fertilized N levels. Conclusively, it is suggested that heavy straw mulching was not efficient for rice seedling establishment and nitrogen usage.e.

• 한국작물학회지
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• 제46권1호
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• pp.64-67
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• 2001

Snap bean is a new corp in Korea but believed to have a great deal of potentials for both domestic and overseas markets. The present study was performed to obtain the basic information about growth- and quality-related characteristics and to determinate the optimum seeding date and harvesting time for snap bean. Pod yield was significantly affected by seeding date. The highest pod yield was obtained from March 20 for determinate type and April 4 for indeterminate one, respectively, with the range of 13.0-23.7 t/ha. The pod length of indeterminate type was over 13cm, and the pod length was over 5 grams. The pod width for tested varieties was less than 1.0cm. Considering the pod growth characters such as pod length, pod width, and pod weight, the optimum harvesting time for immature pods of snap bean was supposed to be from 15 to 20 days after flowering. The daily yield of snap bean was begun to sharply increase from 15 days after the first flowering and the maximum yield was recorded at 30 days after flowering. For the accumulated yield, nearly 90% of total yield was obtained in 42 days after flowering.

• 농업과학연구
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• 제42권2호
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• pp.87-92
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• 2015

This study was conducted to evaluate the herbicidal efficacy of carfentrazone-ethyl mixtures in direct-seeding flooded rice. The efficacy of three different carfentrazone-ethly mixtures was greater than pyrazosulfuron-ethyl pyriminobac-methyl GR (PP GR). Weeding efficacy of three different carfentrazone-ethly mixtures was more than 96.9%. No phytotoxic effect was observed in the rice based on the plant height and the number of tillers. Yield of rice un three different carfentrazone-ethly mixtures application was more than both in the PP GR and in the hand weeding. Based on these data, three different carfentrazone-ethly mixtures can be applied to provide an effective weed management in direct-seeding flooded rice.

• Journal of Korean Neurosurgical Society
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• 제49권2호
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• pp.124-127
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• 2011

A 43-year-old male presenting with headache and dizziness underwent craniotomy and gross total resection of an extraaxial tumor was achieved via left occipital interhemispheric approach. The tumor was diagnosed as papillary meningioma arising from the left falcotentorium with such pathologic characteristics of bronchoalveolar adenocarcinoma. At postoperative day 40, he developed generalized tonic clonic seizure and then progressed to a status epilepticus pattern. Brain magnetic resonance imaging showed irregular leptomeningeal enhancement with a significant peritumoral area. Through a cerebrospinal fluid (CSF) study, we identified the meningioma cells of the papillary type from the CSF. At the postoperative day 60, he fell into semicomatose state, and the computed tomography imaging showed low density on both cerebral hemispheres, except the basal ganglia and cerebellum, with overall brain swelling and an increased intracranial pressure. He died on the following day. We experienced a rare case of a papillary meningioma with leptomeningeal seeding.

• 한국환경복원기술학회지
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• 제9권1호
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• pp.41-54
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• 2006

In case of leaving artificial slopes resulting from large-scale constructions, there may be secondary damage caused by soil loss due to erosion and collapse. Furthermore, slope-restoring constructions have a few problems such as monotonous landscape and difficult succession of secondary vegetation due to reckless use of exotic grass, despite attaining the initial purpose of revegetation. To settle this problem, selected plants deemed to be proper for revegetation were used on one of thin vegetation base methods, CODRA SYSTEM, and made seeding mixture experimental plots considering germination rates differing in each season. Native herbs, native shrubs and exotic herbs contents were increased by 30% and 50% respectively, centered on seeding quantity(30g/$m^2$) used as design standard in the seed spray method, in order to figure out proper quantity for revegetation in each season.

• 한국작물학회지
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• 제50권2호
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• pp.79-83
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• 2005

Rice and weed interference in the paddy field caused by resource competition and allelopathy. Evaluation method of active weed suppressive behavior of rice to weed was developed by eliminating light competition at soil condition. Twenty eight days old rice seedlings (6-7 leaf stage) which was grown at saturated, no drainage pot were clipped above $3\~4cm$ from the soil surface. Weeds seeded around clipped rice stem, named ratoon seeding screening method, showed varietal suppressive difference to Echinochloa crus-galli, Echinochloa crusgalli var. praticola and Monochoria vaginalis. Potential allelopathic rice varieties, Sathi, AC1423 and PI312777 showed better suppressive activity to weed seedling growth than Nonganbyeo and Keumobyeo. Weed suppression of one plant of rice cultivars could be evaluated by the cell size of $2.5\times2.5cm$ at rice clipping of seedling 29 days after rice seeding.