• Geophysics and Geophysical Exploration
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• v.4 no.4
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• pp.133-144
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• 2001

An effective seismic reflection technique for mapping the cavities and bedrock surface in carbonate rocks is described. The high resolution seismic reflection images were successfully registered by using the hydrophones employed in the stream-water driven trench, and were effectively focused by applying optimal data processing sequences. The strategy included enhancement of the signal interfered with the large-amplitude scattering noise, through pre- and post stack processing such as time-variant filtering, bad-trace editing, residual statics, velocity analysis, and careful muting after NMO (normal moveout) correction. The major reflections including the bedrock surface were mapped with the desired resolution and were correlated to the seismic crosshole tomographic data. Shallow major reflectors could be identified and analyzed on the AGC (auto gain control)-applied field records. Three subhorizontal layers were identified with their distinct velocities; overburden (<3000 m/s), sediments (3000-4000 m/s), limestone bedrock (>4000 m/s). Taking into account of no diffraction effects in the field records, gravel-rich overburdens and sediments are considered to be well sorted. Based on the images mapped consistently on the whole survey line and seismic velocity increasing with depth, this area probably lacks in sizable cavities (if any, no air-filled cavities).

• Journal of the Korean earth science society
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• v.30 no.3
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• pp.305-316
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• 2009

Experiments to explain fossilization have been introduced in elementary and middle school science textbooks. Most of them have explained the processes by the mold and cast formed by imprint of bivalve or leaf. The processes explained in the textbooks are more similar to that of trace fossil than body fossil, because the external molds from experiment are imprints after the model was taken off. However fossils of the figures in the textbooks are mostly body fossils. Therefore, the students may be willing to equate the experiment process with the fossilization of the body fossils. The misconceptions were confirmed in this study by the questionnaire which asked 9th grade students on this subject. Many students thought that the body fossils were fossilized imprints and the fossils of terrestrial organism were formed on land without transportation, that is, they did not understand well about biostratinomy and crustal movement. The misconception about the environment in which fossils formed was already reported in a survey on the elementary school students, but has not revised until ninth grade. Therefore, to remove the misconception related to the fossilization, the fossil models in the experiments may be replaced by trace fossils, or new experiments for body fossil should be designed.

• Journal of the Korean Institute of Landscape Architecture
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• v.33 no.3 s.110
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• pp.78-83
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• 2005

The purpose of this project is to create small parks in elementary schools in order to improve the educational environment and also to increase the amount of greenspace in the city. Above all, the main goal is to create space for local residents in which they can enjoy their leisure time. During a basic investigation and document investigation of elementary schools in Daegu, I placed the priority on choosing the schools that showed the most promise. Also, by doing a survey about the present conditions at schools, I verified, compared, and analyzed the validity of creating small parks in elementary schools. The summary of the results are as follows. The average area available for building small parte in Daegu elementary schools is $7,447m^2$. Even though this area is not as large as a neighborhood parti the difference is not that great. Therefore, I assumed that building small parks in schools would be as effective as building neighborhood parks. The standard size for a children's parks is $1,500m^2$, and if small parks were to be constructed in all school areas with available space larger than a children's park (i.e., larger than $1,500m^2$), the amount of added park greenspace would equal $1,217,953m^2$. The number of schools with areas under $1,500m^2$ is only 3% of all schools in which small parte can be created(5 schools). Schools that have between $1,500m^2$ and $8,000m^2$of greenspace make up 59.7% of all schools in which small parte can be created (98 schools). Schools that have greenspace of more than $8,000m^2$ make up 37% of all school in which small parks can be created (61 schools). The standard area for neighborhood parte is $10,000m^2$ (building-to-land ratio 20%). Schools that have areas that are larger than the standard area for neighborhood parte make up 31% of all elementary schools in Daegu (61 schools). Therefore city greenspace would increase to a total of $694,805m^2$ by making use of these schools, which would represent 7% of the park greenspace in Daegu.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.31 no.2
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• pp.82-91
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• 2013

This study was performed in order to analysis the landscape change and cause of scenic sites and surrounding environment is located in the Urban Residential Area since modern. The study was carried out using of field observations, literature review, cadaster map analysis from 1962 to 2010, and survey. It trace about Seongnagwon, Mapo Choi Sa-Young's old house, Seoul Seonjamdanji, Seoul Hanyang castle and those can be process of change per period. Also, it examine to original view of cultural assets and analysis about lots alteration with landscape alteration. Seongnagwon has original view which constructed the Songseokjeong and pond in 1954. Mapo Choi Sa-Young's old house has original view that move to Sungbook-dong and restore an old house. Seoul Seonjamdanji has it define original view that remained ruins by 1960's development. Seoul Hanyang castle has original view that stone fortress. Seongnagwon's landscape was changed by institutional factors. Mapo Choi Sa-Young house's landscape was changed by society economic factors. Seoul Seonjamdanji was changed by society economic and institutional factors. Seoul Hanyang castle was changed by technical and institutional factors. Generally cultural heritage of Sungbook-dong was changed by institutional and society economic factors. It is guessed that Seoul urban planning influenced Sungbook-dong development. The establishment of capitalistic economy system was backgrounds to it. Therefore, it expect to realized desirable landscape alteration that recognized potential value as culture resources.

• Journal of Korean Society of Forest Science
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• v.63 no.1
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• pp.1-8
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• 1984

These surveys were conducted to estimate the winter bird population inhabiting in the estuary of Nakdong River by unit distances, by unit times, by sections and by observation points. The results were summarized as follows: 1) A total of 70,032 birds were observed, which composed of 82 species under 27 families. 2) An average of 2,103.06 individuals per kilometer was observed and 23,344.00 individuals per hour. Anatidae showed the most dominance (65.13% of the total), followed by Scolopacidae(14.55%), and Laridae(7.28%). 3) The present population by areas were observed as follows; 61.8% of the total in the tideland and swamp, 31.9% in the surface of water, and 6.4% in the air and land, respectively. 4) Among the five sections, the greatest population was observed in section 3 which figured 22,852 individuals (30.0%), and the least in section 4 (9.8%). 5) In this observation point, six species such as Anas platyrhynchos, Tadorna tadorna, Anser albifrons, Aythya ferina, Calidris alpina and Larus crassirostris were the most dominant birds inhabiting which reached 83.1% of the total.

• Journal of the Korean Society of Industry Convergence
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• v.12 no.2
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• pp.79-83
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• 2009

In this study, actual state of operation of rotary tillage was surveyed in the central part of Korea which includes 29 rural community around Asan city, Choongnam principal. 29 heads of the village and 44 farmers were surveyed at the field with a questionnaire on the operation of rotary tillage with farm tractors. Power requirement of rotary tillage operation was measured at the field of each farmers during rotary tilling operation in the central part of Korea. Summaries of this study are summarized as follows. 1) Operations of tillage and land preparation were found to be carried out with farm tractors by 98 percents which are results of the survey on 29 heads of the village and 44 farmers. 2) More than half of the farms had tractors with horsepower more than 38 kW which states that most tractors were supplied in middle and large size. 3) The case of applying secondary tillage after the first primary tillage were 79 percent among the most of operations of tillage and field preparation. Rotary tillage were carried out on the most of wet paddy fields and only 14 percent of dry fields were cultivated with rotary tillage. 4) 63.6 percent of farm tractors were surveyed to meet the recommended field capacity on tillage operation by the government which were ranged from 15.1 to 34.9 ha. And the field capacity of these farm tractors were greater than that of annual total area of operation field, 13.2ha (data from Information of agricultural machinery, National agricultural products quality service, Korea), which states the utilization of agricultural machinery was high in the area surveyed. 5) 46 percent of farmers changed the blade of rotary implement when they used it over the field capacity of rotary blade of 33 ha which is the area of field for rotary operation per a blade change. 55 percent of farmers changed the rotary blade more than once per two years. 6) The required power for rotary operation of each farm tractors were measured as 17.206 kW at untilled paddy field and 34.989 kW at untilled dry field on the average, respectively. The required power for rotary operation was measured as 28.248 kW on the average at the paddy field which had been plowed once and 28.015 at the paddy field that had rotary tillage operation. Untilled dry field showed the highest value of the required power for rotary operation.

• Journal of the Korean association of regional geographers
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• v.19 no.4
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• pp.641-653
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• 2013

This study analyzed the location of manufacturing industries and works' residence in Yangsan city of which large part of industries were relocated from Busan metropolitan area along the industrial suburbanization process. Through the field survey, in-depth interview, and analysis of statistical data, the study tried to describe the relocation characteristics of manufacturing industries in Yangsan city. The results of the analysis are as follows: 1. The relocation rate of manufacturing industries from Busan to Yangsan was very high in 1980s. As a result of analysis, the first prime factor on relocation was the site problem for industrial land use. But for the newly starting industries, the most important factor was the subcontract networks among industries which differed from relocated ones. 2. The industrial suburbanization process influenced on the industrial structure strongly, as the compositional weight of rubber and plastic industries in Yangsan became greater and the size of the major plants got larger. 3. The manufacturing industries in Yangsan city were widely distributed on the main national industrial districts. Also, they were diffused out to the other places beyond the boundary of industrial districts. 4. The commuting workers' residence in Busan, employed by the plants of Yangsan marked 44.5%. That confirmed the strong influence of Busan labor market.

• Geophysics and Geophysical Exploration
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• v.14 no.3
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• pp.220-226
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• 2011

In the elastic wave equations, both horizontal and vertical displacements are defined. Since we can measure both the horizontal and vertical displacements in field acquisition, these displacements compose a displacement vector. In this study, we propose a frequency-domain elastic waveform inversion technique taking advantage of the magnitudes of displacement vectors to define objective function. When we apply this displacement-vector objective function to the frequency-domain waveform inversion, the inversion process naturally incorporates the back-propagation algorithm. Through the inversion examples with the Marmousi model and the SEG/EAGE salt model, we could note that the RMS error of the solution obtained by our algorithm decreased more stably than that of the conventional method. Particularly, the density of the Marmousi model and the low-velocity sub-salt zone of the SEG/EAGE salt model were successfully recovered. Since the gradient direction obtained from the proposed objective function is numerically unstable, we need additional study to stabilize the gradient direction. In order to perform the waveform inversion using the displacementvector objective function, it is necessary to acquire multi-component data. Hence, more rigorous study should be continued for the multi-component land acquisition or OBC (Ocean Bottom Cable) multi-component survey.

• Journal of the Korean Geographical Society
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• v.41 no.3 s.114
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• pp.331-345
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• 2006

This study deals with geomorphological process of the sand dune landform including the distribution and surface environments, characteristics of sediments, origins and moving processes in lower reach and mouth delta of Duman River, Northeast Korea and China. The methodology of the study includes image analysis of Landsat TM(1992.10) and ETM(2000.9) and Spot(2005.4) for analysis of land cover, 2 times field survey for recognition of landform and acquisition of sediments raw data materials, and grain analysis and exoscopy about raw data materials. The geomorphic elements from satellite image analysis are composed of the delta, sand spit, active and stable dune, sand bar and riparian vegetated zone. Results of the grain analysis indicate the sediments originated from marine coastal zone than riverine one. This means that present sand dune not so much reflect present climatic and geomorphic environments. Result of the exoscopy analysis show that ratio of quartz, which is comparatively resistant to environment, is highest as $65{\sim}83%$ out of sediments. But the surface of the $30{\sim}40%$ of mineral grains was coated by yellow-colored stained materials, due to chemical weathering. Some grains show rough skin, looking as acicular, network structure and etching pits, affected by physical and chemical weathering.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.30 no.3
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• pp.29-41
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• 2012

This study's objective is to inform people of the value and identity and to understand the cultural landscape characteristics of coastal village forest, which have not been studied in-depth in previous studies. This study was conducted by selecting 10 village forest sites in the southern coast of Gyeongsangnam-do, Korea and the present state of forests were investigated through bibliographical and on-the-spot survey, as well as interviews with local villagers. The following points(characteristics of traditional culture, practical characteristics, scenic characteristics) are the important factors for analyzing cultural landscape characteristics of coastal village forest verified through the study. First, The coastal village forest in the village commons is mental space for the local community affected by folk belief rather than confucian backgrounds. Second, The coastal village forest is a reasonable space contriving economic efficiency and solving the real problems facing the coastal village. Third, The coastal village forest identities should be understood the land use around village and behind mountain from the sea of wide range rather than confined to just a forest consisting of trees. This study's significance is to make the basic data and to enhance the value of the coastal village forest unnoticed. In addition, the subjects of the study should be extended to the east and west coastal village forests and subsequent research should be conducted to notification the characteristics and differences of each coastal village forest.