• 한국해양학회지
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• v.30 no.2
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• pp.91-115
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• 1995

Air-sea heat fluxes in the East Sea were estimated from the various ship's data observed from 1961 to 1990 and the JMA buoy #6 data from 1976 to 1985. The oceanic heat transport in the sea was also determined from the fluxes above and the heat storage rate of the upper layer of 200m from the sea surface. In winter, The incoming solar radiation is almost balanced with the outgoing longwave radiation. but the sea loses her heat through the sea surface mainly due to the latent and sensible heat fluxes. The spatial variation of the net surface heat flux is about 100 Wm/SUP -2/, and the maximum loss of heat is occurred near the Tsugaru Strait. There are also lots of heat losses in the southern part of the East Sea, Korea Strait and Ulleung Basin. Particularly, the heat strong loss in the south-western part of the sea might be concerned with the formation of her Intermediate Homogeneous Water. In summer, the sea is heated up to about 120∼140 Wm/SUP -2/ sue to strong incoming solar radiation and weak turbulent heat fluxes and her spatial variation is only about 20 Wm/SUP -2/. The oceanic heat flux is positive in the southeasten part f the sea and the magnitude of the flux is larger than that of the net surface heat flux. This shows the importance of the area. In the southwestern part of the sea, however, the oceanic heat flux is negative. This fact implies cold water inflow, the North Korean Cold Water. The sigh of net surface heat flux is changed from negative to positive in March and from positive to negative in September. The heat content in the upper surface 200 m from the sea surface reaches its minimum in March and maximum in October. The annual variation of the net surface heat flux is 580 Wm/SUP -2/ in southwestern part of the sea. The annual mean values of net surface heat fluxes are negative, which mean the net heat transfer from the sea to the atmosphere. The magnitude of the flux is about 130 Wm/SUP -2/ near the Tsugaru Strait. The net surface fluxes in the Korea Strait and the Ulleung Basin are relatively larger than those of the rest areas. The spatial mean values of surface heat fluxes from 35$^{\circ}C$ to 39$^{\circ}$N are 129, -90, -58, and -32 Wm/SUP -2/ for the incoming solar radiation, latent hear flux, outgoing longwave radiation, and sensible heat flux, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.3
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• pp.121-133
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• 2023

The purpose of this study was to improve weed management systems under varying carbon dioxide concentrations and temperatures by evaluating the growth of Acalypha australis and observing the efficacy of four foliar and four soil herbicides, as well as measuring phytotoxicity in soybean crops treated with these herbicides. In both growth chamber and greenhouse conditions, plant height and shoot fresh weight of Acalypha australis increased as temperature increased. The variable to maximum fluorescence ratio (Fv/Fm), relative electron transport rate (ETR), plant height, leaf area, and shoot fresh weight of Acalypha australis were higher at carbon dioxide concentrations of 800 ppm than at 400 ppm. The efficacy of a foliar herbicide, glufosinate, on Acalypha australis was lower at 30℃ than at 20℃ and 25℃ in the growth chamber condition and was also lower at 29℃ than at 21℃ and 25℃ in greenhouse conditions. In contrast, mecoprop efficacy on Acalypha australis was lower at 20℃ and 25℃ than at 30℃ in growth chamber conditions and lower at 21℃ and 25℃ than at 29℃ in greenhouse conditions. Glyphosate efficacy was lower at 21℃ than at 25℃ and 29℃ under greenhouse conditions. With soil herbicides, metolachlor and ethalfluraline, efficacies were higher at relatively high temperatures under both growth chamber and greenhouse conditions. However, in the case of linuron, the difference in efficacy was not observed under varying temperatures in both growth chamber and greenhouse conditions. When ¼ of the recommended glyphosate rates were applied to Acalypha australis, efficacy was lower under 800 ppm carbon dioxide concentrations than under 400 ppm. In contrast, when ¼ of the recommended rate of bentazone was applied to Acalypha australis, efficacy was higher under 800 ppm carbon dioxide concentrations than under 400 ppm. Despite application rates, glufosinate efficacy differed insignificantly under different carbon dioxide concentrations. When applied at ¼ of the recommended rate, the efficacy of ethalfuralin was higher under 800 ppm carbon dioxide concentrations than under 400 ppm. However, efficacies of other herbicides were not different despite varying carbon dioxide concentrations. Soybean phytotoxicity in crops treated with the recommended rate and twice the recommended rate of soil herbicides was not significantly different regardless of temperature and carbon dioxide concentrations. Overall, weed efficacy of some herbicides decreased in response to different temperatures and carbon dioxide concentrations. Therefore, new weed management methods are required to ensure high rates of weed control in conditions affected by climate change.

• Korean Business Review
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• v.21 no.2
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• pp.137-170
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• 2008

This study is presenting the logistics strategy in the international logistics markets which makes competition and corporation among north-east Asian countries to establishing the multi-pass Eurasian railroads. The countries located in north-east area of Eurasia like China, Japan, Russia and Korea are paying higher costs and disutility to the transportations and communications due to repeated conflicts and confrontations causes from the politic problems. They are being used surface transportation for most of all logistics between Europe and Asia except special merchandises because of characteristic of cargo to be air, the Silk Road remains vestige only which was main logistic passage to this area since BC. So far the Trans-Siberian Railway is being used by Russia mostly as north of Eurasian transport because of difficulties of service. The Trans-China Railway built in 1992 is not accomplishing as a international logistic passages. It is expected to take a long lead time because of characteristic of resource development and poor logistic infrastructure to the countries like Uzbekistan, double landlocked country, Mongolia and Azerbaijan, the countries do not be adjacent to the sea, even they have great economic jump-up plans through the development of their own resources. The Shanghai Cooperation Organization(SCO) start to sail officially in 2001 is constructed with China, Russia, Tadzhikistan, Kyrgyzstan, Kazakhstan and Uzbekistan as regular members of 6 countries and Mongolia, India, Pakistan, Afghanistan and Iran as observers 5 countries. It is started as a military alliance to protect terror, but now, it is expended to cooperate with the traffic, transportation, trade and share of energies. The Russia is doing their best to activate TSR as a government target to developnorth area equivalently, and economic develop of far-east Siberia. And also it is agreed provisionally to improve and repair of rail road between Nahjin and Hassan to connect TSR and TKR( Trans-Korea Railroad) by Russia, North Korea and South Korea with Russian's aggressive efforts. The development plan of this area is over lapped with GTI(Greater Tumen Initiative) promoted by UNDP, and is a cooperated project by 5 countries of South Korea, Mongolia, China, Russia and North Korea, subject to review the appropriation of energy, tour, environment, rail road connection between Mongolia and China and establishing a ferry route to north-east Asia. It is Japanese situation to pay attention to Russia and China even they have been supplying large-scope of infrastructure in Mongol area without any charges, target to get East Asia Main Rail Road to connect Mongolia and Zalubino of Russia. In case of the program for the Denuclearization of North Korea is not creeping, it will be accelerated to connect the TKR and TSR, TKR and TCR by somehow attending United States, including developing program promoted by UN ESCAP. As the result, Korean peninsular will continue the central role of competition and cooperation as in the past, now and future of north-east Asia, as of geographical-economics and geographical-politics whether it is requested or not wanted by neighbor countries.