• Journal of Wetlands Research
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• v.19 no.2
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• pp.223-229
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• 2017

This study analyzed the relationship between environmental factors and the temporal changes of the bird populations during the every January from 1999 to 2016 (18 years) in Donglim reservoir. 'Winter Waterbird Census of Korea' data by National Institute of Biological Resources were used for the bird population data, and principal component analysis and cluster analysis were used to analyze the changes of annual population. The average temperature of January and the average storage rate of the reservoir were used as environmental factors. According to the results of the study, the population changes in the study area can be explained by the increase and decrease of two water bird groups and a mountain bird group. The average temperature of the years when the population of water bird groups increased was more than $1.4^{\circ}C$ in comparison with the year when mountain birds increased. On the other hand, the influence of the water content was not clear. The visiting of Baikal Teal affected by temperature was a factor affecting the other group of water bird and a mountain bird group. The results of this study suggest that the temperature change affects the global spatial distribution of birds and the migration of large population species such as Baikal Teal affects species composition and populations of birds at local scale. Therefore, understanding of environmental changes at large scale and spatial distribution of species and flock contributes to understand the temporal variation of the bird population at regional or local scales.

• Journal of Korean Society of Forest Science
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• v.88 no.4
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• pp.429-437
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• 1999

Heavy metals(Cd, Cu, Pb and Zn) in tree rings of P. thunbergii growing at Onsan Industrial Complex of air polluted area were analyzed to study the condition of heavy metal pollution. The tree ring width began to decrease after operation of factories and decreased abruptly at Onsan Industrial Complex after 1991. Cd contents in tree rings showed 119.4ppb to 867.0ppb level and suddenly increased after 1991. Cu contents showed 309.5ppb to 3686.8ppb, and Pb contents 911.33ppb to 7997.1ppb and fluctuations of those were high after operation of factories. Zn contents showed the highest level of 3528.7ppb to 23826.7ppb and largely ascended after 1960, and increased suddenly after 1992, as compared to former tendency. On the other hand, heavy metal contents in tree rings of P. thunbergii at Gosung of non-air polluted area were far lower than Onsan I. C., and there was a wide difference between both areas after 1990. On the heavy metal contents accumulated in bark of P. thunbergii of both areas, it was higher to 10 times in Cd, 1,000 times in Cu, 285 times in Pb and 133 times in Zn contents at Onsan than at Gosung. In the heavy metal analysis for circle plate and cores, heavy metal contents in cores were generally higher than those in disk and Pb contents showed specially high difference, but pattern of variation by tree age showed a similar tendency.

• Environmental and Resource Economics Review
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• v.18 no.2
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• pp.241-277
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• 2009

The purpose of this paper is to compare technical efficiencies and productivities without and with environmental constraints, and shadow prices of $SO_x$ in Korean and Chinese industries. The technical efficiencies without and with environment in Chinese manufacturing industries are higher than those in Korean manufacturing industries for 2000-2004. Most of individual Chinese manufacturing dominate those of Korean manufacturing in levels of technical efficiency. In terms of productivity changes excluding environmental constraints, the rates of annual growth in Korean and Chinese industries show 1.13 percent and 2.73 percent respectively. But Korean industry in productivity changes considering $SO_x$ reduction shows 2.41 percent, higher rate of growth than 1.58 percent of Chinese industry. In the shadow prices of $SO_x$, the reduction of an additional unit of $SO_x$ in the Korean manufacturing needs a decrease of 1.473 unit of output, while the shadow price of $SO_x$ in Chinese manufacturing is 0.0049, close to zero. Korean manufacturing should be specialized in higher sectors of technical efficiency and productivity and be also kept efficient in pollution abatement cost.

• Journal of Distribution Science
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• v.14 no.3
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• pp.73-83
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• 2016

Purpose - The parcel delivery service(courier) industry all over the world has been expanding its market so far, but its growth has been declining in recent years. In this situation, most parcel delivery companies are having trouble with managing themselves because of the pressure from the customer to increase service level and decrease the rate. The purpose of this study is to provide ways to improve competitive advantages of the parcel delivery service industry by evaluating the multi-period operating efficiency of Korea, Japan and global service providers. Research design, data, and methodology - The data for the period of 2011 to 2014 were collected from the annual reports published by parcel delivery companies. In this study, we analyze the marketability (revenue), profitability (operating profits), and management conditions (net profits) of parcel service companies by combining information on human resources (number of employees) and material resources (total assets and equity). Therefore, the number of employees, total assets, and equity are selected as input variables, and revenue, operating profits, and net profits as the output variables. In this study, DEA (Data Envelopment Analysis) is used to measure the comparative efficiency and MPI (Malmquist Productivity Index) is used to analyze the trend of change of the efficiency for a multi-year period. Results - The operational efficiency scores of medium-sized parcel delivery companies in Korea are higher than other larger competitors such as Korean, Japan and Global larger companies. As of 2014, Logen(1.878) was found to be the most efficient parcel delivery enterprise, followed by KGB (1.224), and Kyoungdong(1.002). Otherwise, Hanjin(0.235), CJ(0.262), Hyundai Logistics(0.657), DHL(0.611), UPS(0.766), FedEx(0.498), TNT(0.350), Yamato(0.762) and Sagawa(0.520), larger sized companies, were done inefficiently. The productivity of parcel delivery companies is influenced by endogenous factors as well as exogenous ones such as changes in business environment and technological advances. Conclusions - Korean medium-sized companies have relatively high efficiency scores in operation. That is why they still survive the competitive market in Korea where market restructuring on the industry has been expected to be conducted for many years. The reason why medium-sized couriers had higher efficient scores than larger couriers is that most of couriers spend more operating expenses versus unit price of delivery which is the amount of money that is needed in order to send a package by parcel service. So the delivery unit price must be taken into account by all the expenses associated with the cost of fuel, labor and maintenance expenses for facilities, etc. therefore, the unit price must be increased to strengthen business competitive power. In order for the industry to have more competitive advantage, the companies need to make profits by increasing demand volume and raising the delivery rate to provide high-quality delivery service to customers. And both endogenous and exogenous change must take precedence in order to strengthen their competitiveness.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.4
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• pp.32-40
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• 2008

In this study, we monitor ice cap using calculated NDSI from September to December in 2001, 2003, 2006, 2007 and snow cover area in 2007 decrease by compare with 2001. Global warming is one of the most important issue in this world. Because global-warming is the reason of various meteorological disasters and extreme weather events in these days and snow and glaciers showed that global warming effect most easily. Snow and glaciers play an important role in Earth cooling system because of their high reflectance. The present study has been carried out monitoring ice cap in Himalayas, using MODIS(Moderate Resolution Imaging Spectroradiometer)data. Indicator to monitoring ice cap, NDSI(Normalized Differenced Snow Index) was used in this study. The NDSI is a spectral band ratio that takes advantage of the spectral differences of snow in visible and short-wave infrared domain to detect snow cover area versus non-snow cover area in a scene. This study is quantitative evaluation about effect of global warming for icecap.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.2
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• pp.103-112
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• 2011

The main objective of this research was to estimate Nitrogen budget of South Korea in 2008. Input-output budgets for nitrogen fluxes were categorized into three sections: cities, agricultural area, and forest. Chemical and biological fixation, dry and wet deposition, imported food and feed were used as the nitrogen input. Crop uptake, volatilization, denitrification, leaching, runoff, and forest consumption were used as the nitrogen outputs. Annual total nitrogen input was 1,294,155 ton/yr, and output was 632,228 ton/yr. Comparison with a previous research in 2005 indicates that nitrogen input was decreased by 1.9% due to the decrease in nitrogen fertilizer while nitrogen output was decreased by 6.3%. Non-point source (NPS) pollution was also estimated by mass balance approach, which increased by 22% than the previous research in 2005. The emission of nitrous oxide ($N_2O$) caused by denitrification was newly examined in this research. About 8,289 ton/yr of $N_2O$ was released from agriculture area and domestic wastewater treatment plant.

• Korean Journal of Weed Science
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• v.4 no.2
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• pp.169-178
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• 1984

This experiment was conducted to find out selective herbicides which are safe to the rice seedlings and to provide effective weed control method in protected semi-irrigated rice seedbed. There was no crop injury in rice with benzophenap [2-(4-2, 4-dichloro-3-methylbenzoyl)-1, 3-dimethyl-pyrazol-5-yl-oxy)-4'-methyl acetophenone] (240g), pyrazoxyfene [1,3-dimethyl-4-(2,4-dichlorobenzoyl)-Sphenacyloxy pyrazole] (200g), chlormethoxynil [2,4-dichlorophenyl-4-nitro-3-methoxyphenyl ether] (180g), dimepiperate [S-(1-methyl-1-phenethyl)-piperidine-l-carbathioate] (210g), dimepiperate + probenazol [3-allyloxy-1,2-benzisothiazol-1,1-dioxide] (210 + 120g) mixture and dimepiperate + probenazol + molinate [S-ethyl-N,N-hexamethylene-thiol-carbamate] (120 + 120 + 120g) mixture at times of application studied. Butachlor [2-chloro-2',6'-diethyl-N-buthoxymethyl acetanilide] + pyrazolate [4-(2,4-dichlorbenzoyl)-1,3dimethyl-pyrazol-5-yl-p-toluene-sulfonate] (70 + 120g) mixture and butachlor + chlormethoxynil (60 + 120g) mixture caused root length to shorten and root viability to decrease. However, the crop injury was recovered at 25 days after seeding. Benzophenap, pyraxoxyfene and butachlor + pyrazolate mixture were effective for weed control when applied at 2 days before seeding. Chlormethoxynil and butachlor + chlormethoxynil mixture was very effective for controlling annual weed. Dimepiperate, dimepiperate + probenazol mixture and dimepiperate + probenazol + molinate mixture did not control most weeds except for Echinochloa crus-galli (L.) Beauv.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.30 no.3
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• pp.150-160
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• 1994

Drift gillnet fishery for neon flying squid in the North pacific was one of the major pelagic fisheries of Korea until 1992, its annual catch was 79, 000M/T as average during 1988-1992, but moratoriumed since 1993 according to the decision of UN. Therefore, for the developing of the new fishing gear for the squid, the seven types of rip hook by automatic squid jigging machine were experimented by the korean research vessel Pusan 851 (G/T 1.126, 2.600 PS) in the North Pacific (38 $^{\circ}$30'-43 $^{\circ}$N, 152 $^{\circ}$E-178 $^{\circ}$W) from July 6. 1993 to August 31. 1993. The investigation on catch rate, dropout rate, and catch condition of the rip hooks related to the fishing lamp power for aggregating the squid were carried out during the period. The results obtained are as follows: The composition of catch by automatic squid jigging machine was 83.9% for neon flying squid. 15.5% for boreopacific gonate squid. 0.6% for boreal clubhook squid, and 0.01% for luminous flying squid. The catch rate of neon flying squid was 94.6% in 13.6-18.3$^{\circ}C$ of surface water temperature and 5.4% in others. The higher catch rate of neon flying squid was made in the range 13.6-18.3$^{\circ}C$ of temperature at the surface and about 1$0^{\circ}C$ of temperature at the 100m layer. The CPUE of neon flying squid in the 13.6-18.3$^{\circ}C$ of surface water temperature was ranged 0.8-11.8kg (8.7kg as average). The mantle length and body weight of neon flying squid caught in the experiment were ranged 18.3-51.3 cm, 140-3, 980g and mean mantle length and mean body weight were 29.4cm, 972g respectively. The catch rate of neon flying squid was the highest at dawn with a value of 25.0% of the total catch. The body weight of neon flying squid caught by the D type hooks was 1.7 times more than that of the A type hooks. The dropout rate of neon flying squid caught by the seven types hooks was 7.9-57.5% (19.0% as average), and dropout rate of the D type hooks was 7.9% with 2.7 times decrease than that of the A type hooks. The catch efficiency of small sized neon flying squid in case of using on-off switch method on fishing lamp in 15 minutes intervals was 2.6 times higher than that of the on-switch method with same fishing lamp power.

• Korean Journal of Organic Agriculture
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• v.27 no.4
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• pp.513-528
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• 2019

Coriandrum sativum L., an annual herbaceous plant of Apiaceae family. The present study evaluated the anti-oxidant activities and anti-inflammatory effects of ethanol extracts of C. sativum. The anti-oxidant activities of C. sativum were measured by total contents of polyphenol, flavonoid, DPPH and ABTS radical scavenging and reducing power activity. And anti-inflammatory effects of C. sativum were measured by LPS-induced RAW 264.7 cells. The results showed that the contents of total polyphenol and flavonoid were 76.03 ± 1.36 mg of gallic acid equivalents/g and 182.23 ± 4.32 mg of rutin equivalents/g at concentration 1 mg/mL of C. sativum. The DPPH radical scavenging activity was found to be 52.8% at 500 ㎍/mL. The ABTS radical scavenging activity was shown in 58.3% after exposure to 1,000 ㎍/mL. Reducing power activity was found to be 66.8% at 2,000 ㎍/mL. The inhibitory effect of NO production was found to be 65% concentration 500 ㎍/mL. In the generation quantity of inflammatory cytokines such as TNF-α and IL-1β in cell culture medium, the expression levels of inflammatory proteins in cells were showed decrease with the increase of concentration. Therefore, we suggest that the C. sativum should be a potential source of alternative anti-inflammatory drug with good anti-inflammatory effects.

• Korean Journal of Environmental Biology
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• v.32 no.4
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• pp.389-394
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• 2014

This study was conducted to find out the soil $CO_2$ emission characteristic due to rain fall pattern and intensity changes. Using Automatic Opening and Closing Chambers (AOCCs), we have measured annual soil respiration changes in Pinus koraiensis plantation at Seoul National University experimental forest in Mt. Taehwa. In addition, we have monitored heterotrophic respiration at trenching sites ($4{\times}6m$). Based on the one year data of soil respiration and heterotrophic respiration, we observed that 24% of soil respiration was derived from root respiration. During the rainy season (end of July to September), soil respiration at trenching site and trenching with rainfall interception site were measure during portable soil respiration analyzer (GMP343, Vaisala, Helsinki, Finland). Surprisingly, even after days of continuous heavy rain, soil water content did not exceed 20%. Based on this observation, we suggest that the maximum water holding capacity is about 20%, and relatively lower soil water contents during the dry season affect the vital degree of trees and soil microbe. As for soil respiration under different rain intensity, it was increased about 14.4% under 10 mm precipitation. But the high-intensity rain condition, such as more than 10 mm precipitation, caused the decrease of soil respiration up to 25.5%. Taken together, this study suggests that the pattern of soil respiration can be regulated by not only soil temperature but also due to the rain fall intensity.