• Korean Journal of Weed Science
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• v.1 no.1
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• pp.69-77
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• 1981

Six herbicides were evaluated to investigate the phytotoxicity of rice plant and the weeding efficacy influenced by the time of application in mechically transplanted paddy field. The amount of each chemical applied was 3 kg, a. i, /ha. Chlormethoxynil : Rotala indica KOEHNE and Lindernia pyxuiaria PHILCOX were effectively controlled when applied on the 12th day after transplanting (12 DAT) and this herbicide was excellent for the control of Echinochloa crusgalli P. BEAUV, Monochoria vaginalis PRESL and Sagittaria pygmaea MIQ, when applied early (7 days after puddling) but its weeding effect for these weeds decreased greatly as the application time became later. It had a controlling effect for Potamogeton distinctus A. BENN, Cyperus serotinus ROTTB and Scirpus hotarui ROXB at the initial period at the earlier application time. Butachlor was effective in controlling E. crusgalli, R. indica and L. pyxidaria at 12 days after transplanting (DAT) but was not effective in controlling P. distinctus and S. pygmaea even at the early application time. M. vaginalis, C. serotinus and S. hotarui were effectively controlled by the butachlor treatment at 7 days after final puddling (2 DBT-SDAT) but this weeding effect decreased at the late application time. A combination of butachlor and naproanilide excellently controlled E. crusgalli, R. indica, L. pyxidaria and S. pygmaea regardless of the application time. For the control of M. vaginalis, C. serotinus and P. distinctus, the weeding effect of this mixtures was much greater than that of the single treatment of butachlor. Perfluidone was excellent for the control of E. crusgalli, R. indica, L. pyxidaria, M. vaginalis and S. pygmaea at either application time tested. P. distinctus, C. serorinus and S. hotarui could be controlled by this chemicals until the time of first observation (23 DAT) but the effect for these weeds somewhat decreased as time passed. The effect of pyrazolate on E. crusgalli, M. vaginalis, S. hotarui and P. distinctus was very excellent regardless of the application time but R. indica and L. pyxidaria could not be completely eliminated by this chemical. This chemical was effective in controlling C. serotinus when applied at 7-9 days after final puddling and showed a controlling effect for S. hotaruionly at the initial period. Piperophos + dimethametryn was very excellent for the control of all the annual weeds and P. distinctus. It showed a controlling effect on S. pygmaea, C. serotinus and S. hotarui only at the initial period. There was no difference in the effects on phytotoxicity and yield between chlormethoxynil and pyrazolate at either times of application tested. The later the application time was, the less the phytotoxicity of butachlor and piperophos+dimethametryne was. The phytotoxicity of butachlor + naproanilide and perfluidone decrease in the plots treated at the later application time. When the last two chemicals were treated at 2 days before transplanting (DBT) the yield decreased as compared with the hand weeded plot.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2002.05b
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• pp.388-389
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• 2002

옥상지반의 무기질계 토양종류와 야생초화류별 식물생육생태를 파악하고자 본 실험을 수행한 결과 초기 발아정도는 버미큘라이트에서 우수한 것으로 나타났으며, 초장과 피복율의 경우도 1, 2차 실험기간동안에는 버미큘라이트가 우수했으나 3차 이후부터는 오히려 펄리아트 처리구에서 효과적인 것으로 확인되었다. 다음으로 야생초화류의 토양종류별 생육특성을 실험한 결과 대체적으로 민들레, 벌개미취, 마타리, 큰달맞이의 생육상태가 우수한 것으로 나타났다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.3B
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• pp.355-361
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• 2008

A water quality analysis of rainwater collected from catchment equipment ($2m{\times}1m$) was conducted to determine its suitability for domestic purposes, in this study. As the results of analysis, the pH of rainwater was $6.3{\pm}0.3$, and the turbidity of rainwater was over the 5 times than drinking water guidelines. For the usage of rainwater as the domestic and drinking water, the rainwater is need to treat. The analysis values of heavy metal as the Pb, Cd, Fe, Mn, ${Cr_6}^+$ and Cu was satisfied with drinking guidelines. Rainwater quality was improved in the rainfall duration. Overall results of analysis support the possibility of rainwater as the domestic and drinking water.

• Korean journal of applied entomology
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• v.31 no.4
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• pp.536-542
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• 1992

Control effects of carbofuran soil incorporation just before transplanting on the early occur-ring rice insect pests were studied in the rice field. Also, its residual effects on the brown planthopper (BPH) were studied by pot experiments. Carbofurn soil incorporation in late May was much more effective in controlling the early occurring rice insect pests such as small brown planthopper, green leafhopper and rice stem borer than carbofuran broadcasting or diazinon (3G) + BPMC (50% EC) treatment in mid June. Residual effects of carbofuran soil incorportaion on the female adult BPH decreased ca. a half one month after treatment. However, its residual effects on the next generation of the BPH lasted much longer; control effects on the next generation were above 90 and 70% on 37 and 46 days after treatment, respectively. From these results, it is thought that carbofuran soil incorporation just before rice transplanting can be a good control method to the early occurring rice insect pests and the brown planthopper immigrating during June. Also, it can suppress immigrating BPH popula¬tion moderately in early July.

• Microbiology and Biotechnology Letters
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• v.35 no.2
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• pp.135-141
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• 2007

To increase the consumer acceptability of yam and the shelf-life of fresh-cut yam, organic acid-treated fresh-cut yam was prepared. When uncontaminated fresh-cut yam was stored at $4^{\circ}C$ for 14 days after treatment with 1% (v/w) organic acids, the browning and microbial putrefaction of fresh-cut yam were inhibited by treatment of acetic acid or maleic acid, whereas treatment of citric acid and ascorbic acid, commonly used browning inhibitors in food industry, did not show apparent effects on the browning and putrefaction of yam. The Inhibitory effects of acetic acid or maleic acid were superior than those of NaOCl (100 ppm), hydrogen peroxide (100 ppm) or commercially available washing solution. Also, treatments of 1% acetic acid, or 1% maleic acid Into artificially-contaminated yam $(10^5\;CFU/g-yam)$ showed strong inhibition of browning and putrefaction during long term storage at $4^{\circ}C$. The growth inhibition test indicated that 0.1% is enough to inhibit the growth of psychrotrophic yam-putrefactive Pseudomonas sp., and treatment of 0.1% acetic acid, or 0.1% maleic acid inhibited the browning and microbial putrefaction of fresh-cut yam. Our results suggested long-term distribution of yam or other root crops products is possible by treatment of organic acid, such as acetic acid, combined with aseptic vacuum packaging technology.

• Proceedings of the Korea Information Processing Society Conference
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• 2002.11a
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• pp.373-376
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• 2002

K-Means 알고리즘은 재배치 기법의 일종으로 K 개의 초기 클러스터중심(centroid)를 중심으로 K 개의 클러스터가 될 때까지 클러스터링을 반복하는 것이다. K-Means 알고리즘은 특성상 초기 클러스터 중심과 새롭게 생성된 클러스터 중심에 따라 클러스터링 결과가 달라진다. 본 논문에서는 K-Means Algorithm 의 초기 클러스터중심 선택 방법과 새로운 클러스터 중심 결정 방법을 개선한 변형 K-Means Algorithm을 제안한다. SMART 시스템에서 제안한 16가지 가중치 계산 방식에 의하여 두 알고리즘의 성능을 평가한 결과 제안한 변형 알고리즘이 재현률과 F-Measure 에서 20%이상 향상된 결과를 얻을 수 있었으며 특정 주제 아래 문서가 할당되는 클러스터링 성능이 우수하였다.

• KSBB Journal
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• v.16 no.3
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• pp.290-294
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• 2001

The removal of nitrogen compounds from waste water is essential and is often accomplished by biological process. The denitrifying bacterium, Paracoccus denitrificans (KCTC 2530), was employed to study the characteristics and the denitrification differences of Permeabilized strains and untreated strains. The permeabilization rate increased with increasing toluene concentration, but some part of the toluene contributed to denaturing the datachment of proteins from the plasma membrane. Permeabilized Paracoccus denitrificans had long lag phase and high specific growth rate in cultivation, and showed excellent denitrification characteristic compared with untreated strains. But, in both cases, the denitrification ability was significantly reduced after 4 or 5 denitrifications. It seems that the strains fall into the death phase when the nutrient was exhausted. When the nutrient recovered to its initial level, the denitrification ability also recovered to the normal level. The results obtained were encouraging enough to apply to practical water treatment situation.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2019.10a
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• pp.94-94
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• 2019

• The Transactions of the Korea Information Processing Society
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• v.6 no.10
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• pp.2608-2617
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• 1999

One of the most important functionality that commercial video storage servers should provide is to maximize the number of concurrent streams and to minimize the initial latency of new requests. In this paper, we propose a data placement scheme whose disk read unit size can be twice large than that of conventional striping methods. The proposed scheme can significantly increase the number of concurrent streams, since the ratio of rotational latency time is decreased and the disks are effectively utilized. The disk scheduling scheme we propose guarantees constant initial latency time. We also propose a procedural design method for a storage server by introducing the concept of allowed initial latency. The comparison with previous research shows that the proposed scheme provides better performance.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2007.04a
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• pp.7-8
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• 2007

Ti을 전극으로 한 RF plasma 를 사용한 표면 처리와 200 eV 이하의 저에너지 반응성 이온빔을 사용한 PI 표면 처리에 의해 초기 및 내열성이 우수한 COF 용 FCCL를 제작하였다. 임계 rf power 이상에서 새롭게 $TiO_2$층의 형성이 접착력 증대의 원인이었으며, Ni-Cr-Zn의 삼원계 접착층의 내열성 향상 특성 등을 연구하였다.