• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.8
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• pp.2052-2063
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• 1998

Various full-scale radio location systems have been developed since ground-based radio navigation systems appeared during World War II, and more recently global positioning systems (GPS) have been widely used as a representative location system. In addition, radio location systems based on cellular systems are intensively being studied as cellular services become more and more popular. However, these studies have been focused mainly on macrocellular systems of which based stations are mutually synchronized. There has been no study about systems of which based stations are asynchronous. In this paper, we proposed two radio location algorithms in microcellular CDMA systems of which base stations are asychronous. The one is to estimate the position of a personal station at the center of rectangular shaped area which approximates the realistic common area. The other, as a method based on road map, is to first find candidate positions, the centers of roads pseudo-range-distant from the base station which the personal station belongs to and then is to estimate the position by monitoring the pilot signal strengths of neighboring base stations. We compare these two algorithms with three wide-spread algorithms through computer simulations and investigate interference effect on measuring pseudo ranges. The proposed algorithms require no recursive calculations and yield smaller position error than the existing algorithms because of less affection of non-line-of-signt propagation in microcellular environments.

• The Korean Journal of Air & Space Law and Policy
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• v.29 no.1
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• pp.199-236
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• 2014

This paper analyses from the perspective of distributive justice the legal mechanisms for international allocation of orbital slots, which are of co-owned nature and thereby limited natural resources in outer space. The allocative function is delegated to the International Telecommunication Union. The Radio Regulation, amongst such other legal instruments as the Constitution and Convention, by which the ITU and contracting States thereof abides, dictates how the orbital positions are distributed. Thus, the RR is thoroughly reviewed in the essay. The mechanisms are in a broad sense categorized into two systems: 'a posteriori system' where the 'first come, first served' principle prevails; and 'a priori system' designed to foster the utilisation of the slots by those who lack space resources and are, in especial, likely to be marginalised under the former system. The argument proceeds on the premise that a posteriori system places the under-resourced States in unfavourable positions in the securement of the slots. In contrast with this notion, seven factors were instantiated for an assertion that the degradation of the distributive justice derived from the 'first come, first served' rule, which lays the foundation for the system, could be either mitigated or counterbalanced by the alleged exceptions to the rule. However, the author of this essay argues for counterevidences against the factors and thereby demonstrating that the principle still remains as an overwhelming doctrine, posing a threat to the pursuit of fair allocation. The elements he set forth are as in the following: 1) that the 'first come, first served' principle only applies to assignments capable of causing harmful interferences; 2) the interoperability of the principle with the 'rule of conformity' with the all the ITU instruments; 3) the viability of alternative registrations, as an exception of the application of the principle, on the condition of provisional and informational purposes; 4) another reference that matters in deciding the priority: the types of services in the TFA; 5) the Rule of Procedure H40 proclaiming a ban on taking advantage of coming first to the Register; 6) the technical factors and equity-oriented norms under international and municipal laws along with; 7) the changes of 'basic characteristics' of registered assignments. The second half of this essay illustrates by examining the relevant Annexes to the Regulation that the planned allocation, i.e., a priori system, bear the structured flaws that hinder the fulfillment of the original purpose of the system. The Broadcasting and Fixed Satellite Systems are the reviewed Plans in which the 'first come, first served' principle re-emerges in the end as a determining factor to grant the 'right to international recognition' to administrations including those who has not the allotted portions in the Plan.

• Korean Journal of Remote Sensing
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• v.38 no.2
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• pp.139-151
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• 2022

SAGD (Steam-Assisted Gravity Drainage) method is widely used for oil recovery in oil sands regions. The SAGD operation causes surface displacement, which can affect the stability of oil recovery plants and trigger various geological disasters. Therefore, it isimportant to monitor the surface displacement due to SAGD in the oil sands region. In this study, the surface displacement due to SAGD operations of the Athabasca oil sands region in Alberta, Canada, was observed by applying Permanent Scatterer Interferometric Synthetic Aperture Radar (PSInSAR) technique to the Sentinel-1 time series SAR data acquired from 2016 to 2021. We also investigated the construction and expansion of SAGD facilitiesfrom Landsat-7/8 time seriesimages, from which the characteristics of the surface displacement according to the oil production activity of SAGD were analyzed. Uplift rates of 0.3-2.5 cm/yr in the direction of line of sight were observed over the SAGDs and their vicinity, whereas subsidence rates of -0.3--0.6 cm/yr were observed in areas more than several kilometers away from the SAGDs and not affected by oil recovery activities. Through the analysis of Landsat-7/8 images, we could confirm that the SAGDs operating after 2012 and showing high oil production activity caused uplift rates greater than 1.6 cm/yr due to the subsurface steam injection. Meanwhile, very small uplift rates of several mm per year occurred over SAGDs which have been operated for a longer period of time and show relatively low oil production activity. This was probably due to the compression of reservoir sandstone due to continuous oil recovery. The subsidence observed in areas except for the SAGDs and their vicinity estimated to be a gradual land subsidence caused by melting of the permafrost. Considering the subsidence, it was expected that the uplift due to SAGD operation would be greater than that observed by the PSInSAR. The results of this study confirm that the PSInSAR can be used as an effective means for evaluating productivity and stability of SAGD in the extreme cold regions.

• The Korean Journal of Quaternary Research
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• v.14 no.1
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• pp.7-31
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• 2000

Quaternary Geological and geophysical investigation was performed at the Eurimji reservoir of Jaechon City in order to interprete depositional environment and genesis of lake sediments. For this purpose, echo sounding, bottom sampling and columnar sampling by drilling on board and GPR survey were employed for a proper field investigation. Laboratory tests cover grain size population analysis, pollen analysis and $^{14}C$ datings for the lake sediments. The some parts of lake bottom sediments anthropogenically tubated and filled several times to date, indicating several mounds on the bottom surface which is difficult to explain by bottom current. Majority of natural sediments were accumulated both as rolling and suspended loads during seasonal flooding regime, when flash flow and current flow are relatively strong not only at bridge area of the western part of Eurimji, connected to stream valley, but at the several conduit or sewage system surrounding the lake. Most of uniform suspend sediments are accumulated at the lake center and lower bank area. Some parts of bottom sediments indicate the existence of turbid flow and mudflow probably due to piezometric overflowing from the lake bottom, the existence of which are proved by CM patterns of the lake bottom sediments. The columnar samples of the lake sediments in ER-1 and ER-3-1 boreholes indicate good condition without any human tubation. The grain size character of borehole samples shows poorly sorted population, predominantly composed of fine sand and muds, varying skewness and kurtosis, which indicate multi-processed lake deposits, very similar to lake bottom sediments. Borehole columnar section, echo sounding and GPR survey profilings, as well as processed data, indicate that organic mud layers of Eurimji lake deposits are deeper and thicker towards lower bank area, especially west of profile line-9. In addition the columnar sediments indicate plant coverage of the Eurimji area were divided into two pollen zones. Arboreal pollen ( AP) is predominant in the lower pollen zone, whreas non-aboreal pollen(NAP) is rich in the upper pollen zone. Both of the pollen zones are related to the vegetation coverage frequently found in coniferous and deciduous broad-leaved trees(mixed forest) surrounded by mountains and hilly areas and prevailing by aquatic or aquatic margin under the wet temperate climate. The $^{14}C$ age of the dark gray organic muds, ER1-12 sample, is 950$\pm$40 years B.P. As the sediments are anthropogenetically undisturbed, it is assumed that the reliability of age is high. Three $^{14}C$ ages of the dark gray organic muds, including ER3-1-8, ER3-1-10, ER3-1-11 samples, are 600$\pm$30 years B.P., 650$\pm$30 years B.P., 800$\pm$40 years B.P. in the descending order of stratigraphic columnar section. Based on the interpretation of depositional environments and formation ages, it is proved that Eurimji reservoir were constructed at least 950$\pm$40 years B.P., the calibrated ages of which ranges from 827 years, B.P. to 866 years B.P. Ancient people utilize the natural environment of the stream valley to meet the need of water irrigation for agriculture in the local valley center and old alluvium fan area.

• Journal of the Korean Institute of Landscape Architecture
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• v.42 no.4
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• pp.48-59
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• 2014

This study was carried out to present raw data on managing the restored urban stream by studying the naturalized plants distributed in Gaeumjeong Stream, Changwon-si, Gyeongsangnam-do, Korea. The results were as follows. The numbers of naturalized plants were summarized as 45 taxa including 17 families, 36 genera, 43 species and 2 varieties. The invasive alien plants were 2 taxa including Ambrosia artemisiifolia and Lactuca sativa. The following summarizes the attributes of the naturalized plants. Most of the plants commonly originated from Europe and North America. The 5 naturalized degree that was widely distributed and had many individual was the most common. Until 1921, after the opening of 1 period was the most common in the introduced period. Section 12 had the highest NI at 41.9%, and the lowest, at 20.5%, in sections 9 and 19 were analyzed. Section 1 had the highest UI at 6.2%, whereas, the lowest, at 2.5%, was calculated in sections 19 and 20. Section 2 showed the highest DI at 16.7%. The first results of the analysis of the causes for the invasion of naturalized plants on the riverside and waterways, and physical factors and maintenance are directly affected. Second, sewage, muddy water and sediment deposits this naturalized plant caused by a chemical factor. Third, it is thought that invasive alien plants are irregular as it happens in biological factor. The proposed management plan naturalized plants, the first, disturbance caused by species management is a young object is removed immediately before flowering scape to eliminate or suppress the propagation of physical methods will be needed. Second, the fact that the national spread of native plant species and planting management does not provide space for the growth is very important. Third, agricultural land is disturbed by agricultural practices by interfering with the action of naturalized plants because the source of the river should be prohibited in agriculture. In the future, if we studied the naturalized plants distributed in restored streams located in Changwon-si, the characteristics of change in the ecosystem impact is expected to be beneficial.

• Journal of Environmental Impact Assessment
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• v.26 no.4
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• pp.272-289
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• 2017

This study analyzed the status of the naturalized plants in islands in Jeollanamdo from an island biogeographic perspective. As a result of a floristic analysis at 47 inhabited islands and 194 uninhabited islands, 30 families and 134 species naturalized plants are reported. The most commonly occurring naturalized plant from 141 islands was Rumex crispus. The average number of naturalized plants by islands is 20.6 species (${\pm}14.22$) at the inhabited islands and 3.7 species (${\pm}3.89$) at the uninhabited islands. Presence of fifty nine naturalized species at Geumodo in Yeosu-si is the largest in number. The naturalization ratio, which is the ratio of naturalized plants to native plants, is 7.66% (${\pm}3.96$) in the inhabitable islands and 4.97% (${\pm}3.70$) in the uninhabitable islands. The naturalization ratio among islands of the West Sea in Jeollanam-do is 5.92% (${\pm}4.49$), and it is higher than 4.96% (${\pm}2.15$) in islands in the South Sea. Especially, the naturalization ratio at the inhabitable islands, i.e., 8.39% (${\pm}4.37$) at the islands of the West Sea is higher than 5.80% (${\pm}1.41$) at islands in the South Sea. The naturalization ratio of naturalized plants at the islands shows positive correlation with the size of the island (r=0.412, p<0.01), but the correlations with distance from the mainland and altitude above sea level are not significant. Eight ecosystem disturbing species designated by law are reported, and each species shows distinct distributional ranges. The regional differences in the number of naturalized plant species seem to be a result of the complex reflection of natural and human environmental factors, such as the degree of traffic between mainland and islands, degree of cultivation activities, along with the physical environmental differences. Since islands have limited habitats and resources, islands could be more vulnerable to the incoming species from outside, and environmental changes than mainland. Therefore, continuous monitoring and management against the naturalized plants in islands are needed.

• Korean Journal of Environmental Agriculture
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• v.25 no.1
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• pp.7-13
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• 2006

Plastichouse cultivation for crops and vegetables in the winter has been widely popularized in Korea. In the vinylhouse Ultraviolet B penetration is lower than in the field, and so some problems, as plant overgrowth and outbreak of disease, occurred frequently. The effect of artificial supplement ultraviolet B $(UV-B:280{\sim}320nm)$ radiation on the physiological responses and yield of perilla (perilla frutescens) was investigated UV-B ray was radiated on perilla with the 10th leaf stage at the distance of 90, 120 and 150 cm from the plant canopy for 30 days after planting in the vinylhouse. The production of fresh perilla leaves was high in the order of plastic house, ambient+50% of supplemental UV-B, ambient ambient+100% of supplemental UV-B. Enhanced UV-B radiation affected the intensity of thirty-three proteins in 2-dimensional electrophoretic analysis of proteins and ten proteins out of them seemed to be responsive to UV-B : a protein was, ATP synthase CF1 alpha chain, down regulated and nine proteins (Chlorophyll a/b bindng protein type I, Chlorophyll a/b binding protein type II precursor, Photosystem I P700 chlorophyll a apoprotein A2, DNA recombination and repair protein recF, Galactinol synthase, S-adenosyl-L-methionine, Heat shock protein 21, Calcium-dependent protein kinase(CDPK)-like, Catalase) were up-regulated.

• Korean Security Journal
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• no.12
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• pp.149-175
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• 2006

The purpose of this study is to understand and analyze the character of Islamic fundamentalism and Middle-Ease Terrorism. The aim of Islamic fundamentalism is reconstruction of Ummah(Muslim Unity), thee early society of Muhammad's age. Islamic movement insist to restore the spirit of Islam and purify the society of Islam from the United State and Western world. Now, Islamic fundamentalism movement as a new ideology, appeals to muslim in the world. The concept of modern national state from the Western countries do not accord with the traditional Islamic principles of reign and a spirit of nationalism. On the other hand, Islamic movement have no legitimacy in the system of modern state which govern the Arab world, regardless of the form of government. For this reasons, Islamic fundamentalist have an insecure position and their political activities. It is yet far from their purpose, to reconstruct the muslim unity, to realize the Islamic political principle close to their practical methods. Yet Islamic fundamental movement have not overcome the system of secular state. The Middle East terrorism supported by government might be eradicated by America's anti-terrorism policy. However, it will be serious and spread all over the world that the terrorist attack against the U. S. and western countries is acted by militant warriors of Islamic fundamentalism, uniting Arab and Islamic people's emotions against America and western countries. There are some reasons that we need to focus on the Arab and Islamic fundamentalism. We need to get out of misunderstanding and discrimination about Islamic religion and culture from America's and Western' standard Which are only their new world order. The discrimination of America and western nations against muslim could make other ideologies, opposite to the world peace. There are a lot of foreign workers from Islam countries in Korea. We need to give consideration and attention to them for the our globalization and world peace. It is time to consider what to do for the nation's profit(economical, political, strategic)with right understanding. We are not safe and free from the terrorism yet.

• Korean Journal of Environment and Ecology
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• v.18 no.4
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• pp.369-381
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• 2004

This study was achieved to present the way to restore the Seonheulgot pasture-grassland damaged by landuse and interference for a long time to evergreen broad-leaved forests as the native vegetation structure. As a result of analyzing ecological succession tendency of structure in survey area, we established the optimal restoration model. The total of survey sites were 26, and the classified plant community types were four types by M.I.P of dominant woody species. Finally we classified the four types based on diameter of dominant woody species in canopy layer. The six community types are as follows: Community I was runner-shrub forest, community II was evergreen broad-leaved shrub forest, and community III was evergreen broad-leaved forest of small diameter. Community IV and V were evergreen broad-leaved forest of middle diameter. Community Ⅵ was evergreen broad-leaved forest of large diameter. The number of constituent species was 24 in community I, 28 in community II as the shrub forest, 16 as the evergreen broad-leaved forest of small diameter, 29 in community III, 30 in community IV as the evergreen broad-leaved forest of middle diameter and 27 in community Ⅵ as the evergreen broad-leaved forest of large diameter. The range of Shannon's index of all communitys was from 0.8763 to 1.2630 and the Similarity index between the community composed of middle diameter woody species and large diameter woody species. The ecological succession of community I, II, and III were changed from pasture-grassland to broad-leaved forest and the structure of community IV, V, and Ⅵ was similar to evergreen broad-leaved forest in warm temperate region. We suggest the restoration planting model evergreen broad-leaved forest of in Seonheulgot pasture-grassland, as follows: The target restoration vegetation were Castanopsis cuspidata var. sievoldii community and Queycus glauca community. Castanopsis cuspidata var. sievoldii and Quercus glauca should be dominant woody species in canopy layer, the number of trees was 10 per 100$m^2$, and Castanopsis cuspidata var, sievoldii, Quercus glauca, Camellia japonica, and Eurya japonica should be dominant woody species in the understory layer, the number of trees was 14 per 100$m^2$.

• Korean Journal of Environment and Ecology
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• v.30 no.4
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• pp.771-782
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• 2016

For basic information collection for the ecological management of forest vegetation in Korean island areas, forest vegetation between inhabited(Daemodo) and uninhabited(Gudo) island was classified in the Z-M phytosociological method and their ecological characteristics in terms of both floristic composition and structure analyzed. Forest vegetation of Daemodo and Gudo were divided into a total of 11 units and 8 units, respectively. Total cover and species diversity index(H') of forest vegetation showed significant differences between the two island, Daemodo has a high value in the tree layer, but, Gudo has a high value in the shrub layer. Composition of Life forms, Daemodo was N-$R_5-D_2$-e and Gudo MM-$R_5-D_2$-e. Family importance value(FIV), Daemdo has a high value in Theaceae(12.2) and Pinaceae(12.0) and Gudo in Lauraceae(16.5) and Fagaceae (11.6). The percentage of the total number of species in the family level, Daemodo is Asteraceae(4.5%) was the highest and Gudo is Liliaceae(7.3%). Indicator species of forest vegetation of the two islands, Daemodo is Nanophanerophytes(N) including Smilax china, Ligustrum japonicum and Eurya japonica was significant inicator species and Gudo is Megaphanerophytes(MM) including Dendropanax morbiferus, Castanopsis sieboldii and Actinodaphne lancifolia.