• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.25 no.6_1
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• pp.507-516
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• 2007

Segmentation and organization of the LiDAR (Light Detection and Ranging) data of the Earth's surface are difficult tasks because the captured LiDAR data are composed of irregularly distributed point clouds with lack of semantic information. The reason for this difficulty in processing LiDAR data is that the data provide huge amount of the spatial coordinates without topological and/or relational information among the points. This study introduces LiDAR data segmentation technique by utilizing histograms of the LiDAR height image data and analyzing roof shape for 3D reconstruction and visualization of the buildings. One of the advantages in utilizing LiDAR height image data is no registration required because the LiDAR data are geo-referenced and ortho-projected data. In consequence, measurements on the image provide absolute reference coordinates. The LiDAR image allows measurement of the initial building boundaries to estimate locations of the side walls and to form the planar surfaces which represent approximate building footprints. LiDAR points close to each side wall were grouped together then the least-square planar surface fitting with the segmented point clouds was performed to determine precise location of each wall of an building. Finally, roof shape analysis was performed by accumulated slopes along the profiles of the roof top. However, simulated LiDAR data were used for analyzing roof shape because buildings with various shapes of the roof do not exist in the test area. The proposed approach has been tested on the heavily built-up urban residential area. 3D digital vector map produced by digitizing complied aerial photographs was used to evaluate accuracy of the results. Experimental results show efficiency of the proposed methodology for 3D building reconstruction and large scale digital mapping especially for the urban area.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.10A
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• pp.962-968
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• 2002

Reliable high-speed data communications over insufficient channel bandwidth is one of the major challenges of harsh wireless environments that push the achievable spectral efficiency far below its theoretical limits. A Quadrature amplitude modulation (QAM) scheme is a userful modulation technique for achieving high data rate transmission without increasing the bandwidth of wireless communication systems. The exact general bit error rate (BER) expression of arbitrary rectangular quadrature amplitude modulation has not yet been derived. In this paper, a generalized closed-form expression for the BER performance of rectangular QAM with Gray code bit mapping is derived and analyzed in the presence of additive white Gaussian noise (AWGN) channel. First we analyze the BER performance of an I-ary PAM scheme. Regular patterns in the k-th bit error probability are observed while developing the EBR expression. From these patterns we provide the exact and general closed-from EBR expression of an I-ary PAM. Then we present a general closed-from expression for BER of an arbitrary IXJ rectangular QAM by considering that this signaling format consists of two PAM scheme, i.e., I-ary and J-ary PAM. A simple approximate BER expression for rectangular QAM is given as well.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39B no.9
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• pp.614-619
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• 2014

In WSN (Wireless Sensor Networks) based surveillance system, it needs to know the occurrence of events or objects and their locations, because the data have no meaning without location information. Using traditional 2D localization mechanisms provide good accuracy where altitude is fixed. But the mapping the position estimated by 2D localization to the real world can cause an error. Even though 3D localization mechanisms provide better accuracy than 2D localization, they need four reference nodes at least and high processing overhead. In our surveillance system, it is needed to estimate the height of the detected object in order to determine if the object is human. In this paper, we propose a height estimation mechanism which does not require many reference nodes and high complexity. Finally, we verify the performance of our proposed mechanism through various experiments.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.2
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• pp.141-146
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• 1984

Variation of soil characteristics and purity were examined within mapping unit and estimates were given for the number of samples required to reach predetermined levels of accuracy for black soil, VDBr. soil, DBr. soil, and brown soil in Jeju. Variation of chemical properties except pH and CEC was higher than that of physical properties. Brown soil showed the lowest variation and hence required the smallest sample size. The soils examined were correctly classified with regard to brown soil at purity 74.1, to DBr. soil 60.8, to black soil 55.6, and to VDBr. soil 46.9%. Sample calculation was presented which showed approximate sample sizes required to detect the difference of 10 and 20% of the mean with 0.95 confidence level.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.2
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• pp.128-133
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• 1985

Variability of soil characteristics and purity were statistically summarized within mapping units and estimates were given for sample sizes required to reach predetermined levels of accuracy in mountainous area soils. Total variances within mapped soil series (expressed as CV): 30-60% for physical properties and CEC relatively affected by management and 80-230% for chemical properties except for pH affected by management. Means of some chemical properties were estimated on the assumption of log-normal distribution. These soils were correctly classified with regard to order at 73.9, to great group 56.9, and to series 47.4%. Approximate sample sizes required to detect the difference of 10 and 20% of the true mean with 0.95 confidence level were presented.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.3
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• pp.254-259
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• 1985

Variability of soil characteristics and purity were statistically summarized within mapping units and estimates were given for sample sizes required to reach predetermined levels of accuracy in mountain-foot slope soils. Total variances within mapped soil series (expressed as CV): 12-44% for pH, CEC, and particle size distribution was relatively unaffected and 56-196% for OM, ext.-cations, and available $P_2O_5$, affected by management. Means of some chemical properties were estimated on the assumption of lognormal distribution. These soils were correctly classified with regard to order at 52.2%, to great group 53.7%, and to series 39.7%. respectively. Approximate sample sizes required to detect the difference of 10 and 20% of the true mean with 0.95 confidence level were presented.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.3
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• pp.134-146
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• 2023

Phytophthora root rot (PRR) is a major soybean disease caused by an oomycete, Phytophthora sojae. PRR can be severe in poorly drained fields or wet soils. The disease management primarily relies on resistance genes called Rps (resistance to P. sojae). This study aimed to identify resistance loci associated with resistance to P. sojae isolate 40468 in Daepung × CheonAl recombinant inbred line (RIL) population. CheonAl is resistant to the isolate, while Daepung is generally susceptible. We genotyped the parents and RIL population via high-throughput single nucleotide polymorphism genotyping and constructed a set of genetic maps. The presence or absence of resistance to P. sojae was evaluated via hypocotyl inoculation technique, and phenotypic distribution fit to a ratio of 1:1 (R:S) (χ² = 0.57, p = 0.75), indicating single gene mediated inheritance. Single-marker association and the linkage analysis identified a highly significant genomic region of 55.9~56.4 megabase pairs on chromosome 18 that explained ~98% of phenotypic variance. Many previous studies have reported several Rps genes in this region, and also it contains nine genes that are annotated to code leucine-rich repeat or serine/threonine kinase within the approximate 500 kilobase pairs interval based on the reference genome database. CheonAl is the first domestic soybean genotype characterized for resistance against P. sojae isolate 40468. Therefore, CheonAl could be a valuable genetic source for breeding resistance to P. sojae.