• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.2
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• pp.291-298
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• 2022

Recently developed drones are inexpensive and very convenient to operate. As a result, the production and utilization of spatial information using drones are increasing. However, most drones acquire images with a low-cost global navigation satellite system (GNSS) and an inertial measurement unit (IMU). Accordingly, the accuracy of the initial location and rotation angle elements of the image is low. In addition, because these drones are small and light, they can be greatly affected by wind, making it difficult to maintain a certain overlap, which degrades the positioning accuracy. Therefore, in this study, images are taken at different times in order to analyze the positioning accuracy according to changes in certain exterior orientation parameters. To do this, image processing was performed with Pix4D Mapper and the accuracy of the results was analyzed. In order to analyze the variation of the accuracy according to the exterior orientation parameters in detail, the exterior orientation parameters of the first processing result were used as meta-data for the second processing. Subsequently, the amount of change in the exterior orientation parameters was analyzed by in a strip-by-strip manner. As a result, it was proved that the changes of the Omega and Phi values among the rotation elements were related to a decrease in the height accuracy, while changes in Kappa were linked to the horizontal accuracy.

• Journal of Cadastre & Land InformatiX
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• v.53 no.1
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• pp.5-20
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• 2023

The government is operating a course evaluation-type qualification system for the purpose of overcoming the limitations of the test-type qualification system and cultivating talents with practical skills applicable to related industries. However, there is a part that does not match the purpose of the course evaluation qualification system by educating competency units in the field of surveying rather than the field of cadastral field in the education and training course of the course evaluation qualification. Therefore, this study closely analyzed the course evaluation qualification system in the cadastral field and suggested improvement plans accordingly. First, NCS in the cadastral field has not been supplemented or developed since its development in 2014, and there are many parts that do not conform to the current laws, so supplementary development is necessary. Second, It was proposed to improve the optional competency unit in the field of surveying to the NCS competency unit in the cadastral field. In addition, if the 12 competency units of the current NCS in the cadastral field are designated as essential competency units and education and training are operated, it will be possible to foster working-level talents with sufficient competency at the cadastral engineer level. However, for practical system operation and application, supplementation and development of NCS in the cadastral field, which is used for education and training of the course evaluation qualification system, must be preceded.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.24 no.1
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• pp.89-97
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• 2006

Soil erosion has caused serious environmental problems which threaten the foundation of natural resources. In this paper, we chose RUSLE erosion model, which could be connected easily with GSIS and available generally in mid-scale watershed among soil erosion models, and extracted factors entered model by using GSIS spatial analysis method. First, this study used GIS database as soil map, DEM, land cover map and rainfall data of typhoon Memi (2003) to analyze soil loss amount of Dam basin. To analyze the changes of soil loss in considering basin characteristics as up-, mid- and downstream, this study calculated soil erodibility factor (K), topographic factors (LS), and cover management factor (C). As a result of analysis, K and LS factors of upstream showed much higher than those of downstream because of the high ratio of forest. But C factor of downstream showed much higher than that of upstream because of the high ratio of agricultural area. As a result of analysis of soil loss, unit soil loss of upstream is 4.3 times than soil loss of downstream. Therefore, the establishment of countermeasures for upstream is more efficient to reduce soil loss.

• Journal of Ecology and Environment
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• v.38 no.4
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• pp.505-515
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• 2015

The objectives of this study were to determine the effects of stream nutrient regime, N:P ratios and suspended solids on fish tolerance/trophic compositions and stream ecosystem health, based on multi-metric model, during 2008-2013. Also, stream ecosystem health was evaluated in relation to chlorophyll-a (CHL) as a measure of algal productivity or indicators of trophic state to water chemical parameters. Total number of sampled fish species were 50 and showed a decreasing trend from 2008 to 2013. The minnow of Zacco platypus, based on the catch per unit effort (CPUE), was the most dominant species (25.9%) among the all species. Spatial heterogeneity was evident in the fish tolerance guilds that showed the dominance of sensitive species (89%) in the headwaters (S1) and the dominance of tolerant species (57%) in the urban. These conditions were directly influenced by concentrations of nutrients and organic matter (COD). The N:P ratios, as a barometer of water pollution, had a negative linear function (R² = 0.40, P < 0.01) with CHL, and the ratios had an important role in changes of COD concentration (R² = 0.40, P < 0.01). Under the circumstances, the N:P ratio directly influenced the relative proportions of fish trophic/tolerance compositions. According to the regression analysis of omnivore (O_m) and insectivore sp. (I_n) on total nitrogen and total phosphorus, nitrogen had no significant influences (P > 0.05) to the two compositions, but phosphorus influenced directly the two guilds [slope (a) = -32.3, R² = 0.25, P < 0.01 in the I_n; a = 40.7, R² = 0.19, P < 0.01 in the O_m]. Such water chemistry and fish trophic guilds determined the stream ecosystem health, based on the multi-metric fish model.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.6
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• pp.845-855
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• 2000

As high as 50% of pregnancies are known to fail and the majority of such losses occur during the peri-implantation period. For the establishment of pregnancy in mammalian species, therefore, implantation of the conceptus to the maternal endometrium must be completed successfully. Physiological events associated with implantation differ among mammals. In ruminant ungulates, an elongation of the trophohlast in early conceptus development is required before the attachment of the conceptus to the uterine endometrium. Moreover, implantation sites are restricted to each uterine caruncula where tissue remodeling, feto-maternal cell fusion and placentation take place in a coordinated manner. These unique events occur under strict conditions and are regulated by numerous factors from the uterine endometrium and trophoblast in a spatial manner. Interferon-tau (IFN-${\tau}$), a conceptus-derived anti-Iuteolytic factor, which rescues corpus luteum from its regression in ruminants, is particularly apt to play an important role as a local regulator in coordination with other factors, such as TGF-${\beta}$, Cox-2 and MMPs at the attachment and placentation sites.

• Journal of Korean Society for Geospatial Information Science
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• v.21 no.4
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• pp.29-35
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• 2013

Generally, Calculation of carbon dioxide absorption in the forest area is calculated using the information of the forest, such as tree height and DBH(Diameter of Breast Height). Tree height and DBH of these are obtained using the remote sensing data such as imagery and information of local forest survey. However, Mixed forest with a high proportion of field survey to lower the accuracy of forest information. In this study, vertical structure of the tree were identified by applying region growing method based on the slope using LiDAR data and height and number of the tree were identified by applying extracting top of the tree algorithm. Through the vertex tree extraction algorithm to identify height of tree and the number of individuals, substitute this for the DBH relation formula which is drawn from data through field surveys. In this, a quantitative calculation of carbon dioxide absorption were able to calculate the basic data. Also, carbon dioxide absorption of three type trees were calculated and average per unit area of carbon dioxide absorption were able to estimate.

• Korean Journal of Agricultural Science
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• v.43 no.4
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• pp.537-546
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• 2016

The development of models for agriculture systems, especially for crop production, has supported the prediction of crop yields under various environmental change scenarios and the selection of better crop species or cultivar. Crop models could be used as tools for supporting reasonable nutrient management approaches for agricultural land. This paper outlines the simplified structure of main crop models (crop growth model, crop-soil model, and crop-soil-environment model) frequently used in agricultural systems and shows diverse application of their simulated results. Crop growth models such as LINTUL, SUCROS, could provide simulated data for daily growth, potential production, and photosynthesis assimilate partitioning to various organs with different physiological stages, and for evaluating crop nutrient demand. Crop-Soil models (DSSAT, APSIM, WOFOST, QUEFTS) simulate growth, development, and yields of crops; soil processes describing nutrient uptake from root zone; and soil nutrient supply capability, e.g., mineralization/decomposition of soil organic matter. The crop model built for the DSSAT family software has limitations in spatial variability due to its simulation mechanism based on a single homogeneous field unit. To introduce well-performing crop models, the potential applications for crop-soil-environment models such as DSSAT, APSIM, or even a newly designed model, should first be compared. The parameterization of various crops under different cultivation conditions like those of intensive farming systems common in Korea, shortened crop growth period, should be considered as well as various resource inputs.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.28 no.2
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• pp.141-148
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• 2017

Objectives: The current study examined the effect of birth weight on the relationship between age and IQ of children, who were born preterm with very low birth weight (VLBW) or extremely low birth weight (ELBW). Methods: The study subjects were 82 children, aged between 3-5 years, who visited the neonatal intensive care unit of a university hospital located in Seoul. The children had been born prematurely with VLBW or ELBW. Their IQ was tested using the performed Korean-Wechsler Preschool and Primary Scale of Intelligence fourth edition. Results: A hierarchical regression analysis showed a significant interaction effect of birth weight and age on Full Scale IQ (FSIQ); the effect of age on FSIQ differed according to birth weight. For the group with VLBW, FSIQ was more likely to be higher with increasing age. Conversely, for the group with ELBW, FSIQ remained low regardless of the age level. In addition, birth weight and age had a significant interaction effect on the Visual Spatial Index. Birth weight had a significant main effect on Verbal Comprehension Index. Conclusion: This research suggested the possibility of predicting the cognitive developmental of premature children, by highlighting the fact that prematurely born children, with VLBW/ELBW, have different cognitive developmental trajectories.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.53 no.1
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• pp.1-9
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• 2004

In this paper, we proposed a hardware(H/W) structure which can compress and recontruct the input image in real time operation and implemented it into a FPGA platform using VHDL(VHSIC Hardware Description Language). All the image processing element to process both compression and reconstruction in a FPGA were considered each of them was mapped into a H/W with the efficient structure for FPGA. We used the DWT(discrete wavelet transform) which transforms the data from spatial domain to the frequency domain, because use considered the motion JPEG2000 as the application. The implemented H/W is separated to both the data path part and the control part. The data path part consisted of the image processing blocks and the data processing blocks. The image processing blocks consisted of the DWT Kernel for the filtering by DWT, Quantizer/Huffman Encoder, Inverse Adder/Buffer for adding the low frequency coefficient to the high frequency one in the inverse DWT operation, and Huffman Decoder. Also there existed the interface blocks for communicating with the external application environments and the timing blocks for buffering between the internal blocks. The global operations of the designed H/W are the image compression and the reconstruction, and it is operated by the unit or a field synchronized with the A/D converter. The implemented H/W used the 54％(12943) LAB(Logic Array Block) and 9％(28352) ESB(Embedded System Block) in the APEX20KC EP20K600CB652-7 FPGA chip of ALTERA, and stably operated in the 70MHz clock frequency. So we verified the real time operation. that is. processing 60 fields/sec(30 frames/sec).

• Journal of the Korean housing association
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• v.16 no.6
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• pp.21-27
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• 2005

The purpose of this study was to explore behavioral patterns on residential spaces such as the patterns of residential space usage and perception on residential spaces. A questionnaire survey and interview were conducted with 426 residents living in apartment with 3 bedrooms, stairway access, and 3-bay style in the City of Seoul, Busan, and Gwangju, during the month of September in 2004. The data was analyzed with frequency, factor analysis by using the SPSS 10.0 for windows, and with proc iml by using SAS. The major findings of this study were that: 1) The most typical activities in the Anbang are $\ulcorner$sleeping and getting dressed$\lrcorner$, $\ulcorner$family communication and T.V. watching$\lrcorner$, and $\ulcorner$private affairs$\lrcorner$ ; Anbang(master bedroom) has been perceived and used as couple's private area. 2) Living room was used as a multi-purpose room carrying out various activities such as $\ulcorner$family interaction$\lrcorner$, $\ulcorner$entertaining guest with meals$\lrcorner$, $\ulcorner$children's private affairs$\lrcorner$, $\ulcorner$private affairs$\lrcorner$, $\ulcorner$hobby activities$\lrcorner$, $\ulcorner$clothes management$\lrcorner$, $\ulcorner$couple interaction$\lrcorner$, and $\ulcorner$occasions$\lrcorner$. 3) The representative patterns of activities in dining-kitchen was food $\ulcorner$preparation$\lrcorner$, and the need for social interaction in DK has been growing. The patterns of residential space usages can be used to develop and evaluate the unit plan of Korean middle-size apartment.