• Korean Journal of Weed Science
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• v.17 no.1
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• pp.73-79
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• 1997

Governments and industry have a growing interest in the harmonization of environmental test methods and risk assessment procedures. OECD are currently producing a set of harmonised test guidelines for studying the environmental fate and ecological effects of pesticides. FAO has published an environmental risk assessment procedure. This procedure, which is similar to those used in US and Europe, is based on calculating the ratio of the toxicity of a pesticide to indicator organisms to their level of exposure to the pesticide. The exposure depends on both the concentration of the pesticide and its bioavailability. Ratios which indicate a pesticide will not produce a harmful effect have been established using ecological field studies. Examples are presented for assessing the risk to aquatic ecosystems, earthworms and honeybees. Long-term field studies(up to 20 years) have also shown that pesticides can be used indefinitely without harming soil fertility. Herbicides can be used to avoid the ecologically damaging effects of using soil cultivations excessively for weed control.

• Information Systems Review
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• v.18 no.3
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• pp.51-71
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• 2016

Tourism products are intangible goods. Given this nature, tourist experience should be recorded and visualized through media, such as pictures, videos, and souvenir. Online platforms played the role of media given the growth of information and communication technology. Tourists post their travels for real-time documentation of their experiences, but they also tend to reminisce about past experiences that they posted on social media. Social media is not only a channel of self-presentation or a means of communication with other people, but it also serves as an archive of electronic records to bring back memories. Given this finding, we investigated the impact of social media on the autobiographical memory (recollection and vividness) of tourists and their intention to revisit a certain destination. The results showed social media interface and the impact of display quality on the recollection and vivid memory. The predictor of memory recollection of tourists is intention to revisit a destination. Social media is considered an archive of travel memory that indulges people to reminisce. Theoretical and practical implications were provided based on these results.

• Korean Journal of Weed Science
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• v.32 no.3
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• pp.170-173
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• 2012

China is one of most important countries for production and consumption of herbicide. Although the chemical weeding technology promoted the development of agricultural modernization in Chinese, it led to the negative effects to agriculture. In particular, the weeds resistant herbicide in paddy field had been serious challenge for safe production of rice. The chemical control technology for weed resistant herbicide with effective, low cost and safety characteristic will be key problem being solved in futhure.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.1
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• pp.46.1-46.1
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• 2014

In understanding "cooling flow" problem and the galaxy-SMBH co-evolution, AGN feedback is considered as one of the most important phenomena. Among various AGN feedback phenomena, X-ray cavities are particularly useful for studying AGN feedback over 10 kpc scales, as the origin of X-ray cavities is believed to be related to radio jet from AGN. For a comprehensive study of X-ray cavities, we collect all available diffuse X-ray data of galaxies in various galaxy environments, ranging from field galaxies to galaxy clusters, using the Chandra X-ray data archive. As a result we build up a sample of 87 targets showing enough X-ray photons to perform the analysis. Using modeling and unsharp masking techniques, we detected X-ray cavities and measured their physical properties (i.e., cavity size) for the 49 targets. Here, we present X-ray cavity properties and discuss environmental effects.

• Weed & Turfgrass Science
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• v.7 no.1
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• pp.72-75
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• 2018

Balloon flower (Platycodon grandiflorum) is one of minor crops in Korea. Only four ACCase inhibiting herbicides are registered for P. grandiflorum and the farmers usually use general but unregistered herbicides which can cause critical phytotoxicity. So, this study was conducted to investigate effects of alachlor and pendimethalin on germination and early growth of P. grandiflorum. To evaluate the effect of alachlor and pendimethalin, two herbicides were treated to the seeds in petri-dish and soil. In the petri-dish, alachlor completely inhibited the germination as well as pendimethalin inhibited the germination slightly but not significantly. In case of soil application, alachlor inhibited germination and plant height of P. grandiflorum significantly as well as pendimethalin inhibited plant height and root length significantly. We showed the possibility of phytotoxicity of alachlor and pendimethalin to P. grandiflorum and strongly suggest that two herbicides should not be used to the cultivation of P. grandiflorum. Unregistered herbicides should not be used for weed management and additional researches for screening of safe herbicide to minor crops should be conducted as soon as possible.

• Korean Journal of Weed Science
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• v.10 no.3
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• pp.227-232
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• 1990

The effects of alachlor [2-chloro-2', 6' diethyl-N-(methoxymethyl) acetanilide] treatment on nucleic acid, amino acid and protein synthesis were studied. The amide herbicide alachlor blocks the biosynthesis of the amino acids isoleucine, valine and aromatic amino acid in oat root tips. Nucleic acid was inhibited, but was not proportional to reduction in protein synthesis. $1{\times}10^{-4}M$ of alachlor treatment of oat roots inhibited 36% DNA synthesis, but DNA synthesis was not inhibited at $1{\times}10^{-5}M$. RNA synthesis was inhibited by $1{\times}10^{-5}M$ and $1{\times}10^{-4}M$ of alachlor 16 and 27%, respectively, while inhibition of protein synthesis did occur at same concentrations. Inhibition of protein synthesis also did not occur at concentration below $1{\times}10^{-4}M$ alachlor. It suggest that inhibition of protein sythesis caused significantly by alachlor($1{\times}l0^{-3}M$) result from secondary action.

• Weed & Turfgrass Science
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• v.7 no.2
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• pp.98-110
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• 2018

The fragrance has a great influence on consumers' cognition, emotional response, attitude, memory, and behavior since the human sense of fragrance is physically and neurologically closer to the hippocampus of the brain. The fragrance materials are exposed to humans ranging from skin interaction to inhalation. We have lots of stories and literature on the usage of fragrance in everyday life in Korea from the Dangun myth to present K-beauty cosmetics. In Korean history, such archives as Dong-Eui-Bo-Gam and Gyu-Gak-Chong-Seo at Joseon Dynasty clearly recorded the application of many weeds for the manufacture of various fragrance products. In recent times, fragrances in weeds have been being applied to touch the consumer's feelings. The present mini-review is an attempt to introduce and discuss fragrant weeds in the archives and in science journals, effects of fragrant weeds on the human electroencephalographic activity, and effects of fragrance on the behavior of consumers. This review could be useful for the development of natural cosmetic and perfumery products from fragrant weeds.

• Korean Journal of Social Welfare
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• v.46
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• pp.60-88
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• 2001

This paper examined the impacts of the welfare reform program, California Work Pays Demonstration Program(CWPDP), implemented in 1992. CWPDP was designed to move welfare recipients into the labor market by reducing the amount of AFDC grants and one-third earned income disregard. The evaluation of the policy impacts on the welfare recipients was conducted in two areas: employment and earnings. This study used a subset of a database created by the California Department of Social Services, and University of California Data Archive and Technical Assistance. The subset is composed of 3,936 AFDC-FG cases selected in LA County: 1,311 control cases and 2,625 experimental cases. The control group was kept on the AFDC rules as of September 1992, while the experimental group was subject to AFDC rule changes implemented under CWPDP. The analyses of the employment and earnings using the random effects probit model and the random effects regression model, respectively, indicated that CWPDP did not effectively encourage female heads to participate in the labor market. It also revealed that CWPDP did not significantly increase the earnings of female heads. The findings imply that the disincentive structure of the public assistance program is not the main barrier preventing female heads from getting jobs and leaving the welfare rolls. Rather, participation in the labor market and exit from welfare is mainly determined by their own demographic characteristics and the economic cycle. Based on the findings, policy implications are suggested on the National Minimum Protection Program in Korea. Those include a flexible exemption rate for the earned income of beneficiaries, affordable child care services, and guaranteed public jobs.

• Korean Journal of Weed Science
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• v.31 no.4
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• pp.401-404
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• 2011

Bromobutide, a paddy field herbicide, can effectively control annual and perennial weeds. It has an excellent weeding effect especially against Monochoria vaginalis and Scirpus juncoides etc. When it is mixed with other herbicides controlling weed spectrum and application timing can be broaden. Bromobutide has stable weeding effects regardless of field and weather conditions, and there is almost no phyototoxic effects to rice.

• Weed & Turfgrass Science
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• v.2 no.2
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• pp.164-169
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• 2013

Alternatives to commercial chemical herbicide are currently being searched and tested due to the numerous adverse effects of commercially available herbicides to the environment. Barnyardgrass (Echinochloa crusgalli) is an important weed species around the world, especially in paddy rice fields. This study focuses on the favorable effects of mixing pyroligneous acids with commercial liquid herbicides. Seedlings were transplanted and grown under greenhouse conditions. The effect of treatment time or leaf-stage on herbicide-pyroligneous acid efficacies was checked, coupled with isolation and quantification of biochemical compounds. Results revealed that herbicide treatment at early post emergence (2~3 leaf stage) of Echnochloa crus-galli leads to effective control. Both liquid herbicides affected fatty acid, protein, and amino acid syntheses as reflected on their contents. The influence of wood vinegar (WV) or rice vinegar (RV) on these compounds was not thoroughly verified due to lack of information on the pyroligneous products. We observed that mixing WV or RV with BCB (bentazone + cyhalof-butyl) gives more favorable results than BUC (butachlor + clomazone), mixed with WV or RV. The result would indicate the potential of mixing pyroligneous acid in reducing herbicide application rate.