• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2004.11a
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• pp.247-252
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• 2004

To secure stability and availability of Rammed Aggregate Pier method as the foundation of a structure, the bearing capacity and failure behavior characteristics was studied through soil laboratory tests in a model ground. In this study, soil laboratory tests use carried out to find the applicability of RAP method as the foundation of a structure. And bearing capacity and the failure mechanism of RAP method was studied according to relative density($60\%,\;70\%,\;90\%$), diameter(45mm, 60mm, 70mm) of each pier ana depth(5cm, l0cm, 15cm, 20cm, 25cm, 30cm). Earth pressure cell is set up approach RAP and 1.0D space at RAP center. Bearing acpacity and the failure mechanism of RAP is investigated by load test As a result, bulging failure was happened in $5\~10cm\;(1.0D\~2.00)$ depth which the maximum lateral earth pressure is acting. Especially, diameter changing of RAP are in inverse proportion to the relative density and the lateral stress is very much influenced by the lateral earth pressure in every layer and tends to decrease according to depth.

• BMB Reports
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• v.51 no.1
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• pp.1-2
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• 2018

Positive selection on a new beneficial mutation generates a characteristic pattern of DNA sequence polymorphism when it reaches an intermediate allele frequency. On genome sequences of African Drosophila melanogaster, we detected such signatures of selection at 37 candidate loci and identified "sweeping haplotypes (SHs)" that are increasing or have increased rapidly in frequency due to hitchhiking. Based on geographic distribution of SH frequencies, we could infer whether selective sweeps occurred starting from de novo beneficial mutants under simple constant selective pressure. Single SHs were identified at more than half of loci. However, at many other loci, we observed multiple independent SHs, implying soft selective sweeps due to a high beneficial mutation rate or parallel evolution across space. Interestingly, SH frequencies were intermediate across multiple populations at about a quarter of the loci despite relatively low migration rates inferred between African populations. This invokes a certain form of frequency-dependent selection such as heterozygote advantage. At one locus, we observed a complex pattern of multiple independent that was compatible with recurrent frequency-dependent positive selection on new variants. In conclusion, genomic patterns of positive selection are very diverse, with equal contributions of hard and soft sweeps and a surprisingly large proportion of frequency-dependent selection in D. melanogaster populations.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.9
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• pp.1547-1553
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• 2008

This paper presents a method that generates various facial expressions of vector graphic character by using the simplified principle component vector. First, we analyze principle components to the nine facial expression(astonished, delighted, etc.) redefined based on Russell's internal emotion state. From this, we find principle component vector having the biggest effect on the character's facial feature and expression and generate the facial expression by using that. Also we create natural intermediate characters and expressions by interpolating weighting values to character's feature and expression. We can save memory space considerably, and create intermediate expressions with a small computation. Hence the performance of character generation system can be considerably improved in web, mobile service and game that real time control is required.

• Journal of the Optical Society of Korea
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• v.16 no.4
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• pp.343-348
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• 2012

This paper described an off-axis five-mirror-anastigmatic telescope. It is composed of three aspheric surfaces and one spherical surface while the third mirror and fifth mirror have the same parameters at the same place. This configuration is useful for having wide field of view. The strip full field of view for the near infrared telescope is $20^{\circ}{\times}0.2^{\circ}$. The entrance pupil is located in front of the first mirror. There is an intermediate image between the second mirror and the third mirror. The entrance pupil diameter is 100 mm and the effective focal length is 250 mm. The spectral range is $0.85-1.75{\mu}m$. The pixel pitch is $15{\mu}m$. The image quality is near the diffraction limit. Some methods were used to restrain the stray light such as a field stop near the intermediate image, the baffle, the narrow-band pass filter and a stop in front of the focal plane.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.24 no.3
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• pp.19-31
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• 2021

The waste landfill that has been used as a park through a stabilization project to provide green space to local residents. Vegetation restoration is necessary for the landfill park project, but it is difficult to restore vegetation due to various disturbances in the landfill. This study analyzed the successional dynamics and ecological characteristics of Robinia pseudoacacia communities from the slopes of Noeul Park by applying the 7-stage successional hypothesis. As a result of the study, there was almost no intermediate successional stage. There are only the early successional stage which Robinia pseudoacacia has an absolute dominance of 100% in the crown and middle layers, and the degeneration successional stage which formed by the introduction of Morus alba. This result showed that the succession of Robinia pseudoacacia communities were not able to proceed to the climax forest due to various disturbances in the waste landfill. Therefore, it was analyzed that it is necessary to induce the succession through intermediate steps such as Morus alba, since it is difficult to transition from Robinia pseudoacacia community to the native Quercus spp. community.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.55.1-55.1
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• 2014

on the observation with the Gemini Multi-Object Spectrograph on the Gemini-South 8.1 m telescope. The radial velocities of four ESCs do not display any sign of systematic motion, unlike the intermediate age carbon stars in NGC 6822. The ages and metallicities derived using the Lick indices show that the ESCs are old (>=8 Gyr) and metal poor ([Fe/H] <= -1.5). NGC 6822 is found to have both metal poor ($[Fe/H]{\approx}-2.0$) and metal rich ($[Fe/H]{\approx}-0.9$) star clusters within 15' (2 kpc) from the center, whereas only metal poor clusters are observed in the outer halo with r >= 20'(2.6 kpc). Based on the kinematics, old ages, and low metallicities of ESCs, we discuss the possible origin of ESCs and the formation of the outer halo of a small dwarf irregular galaxy NGC6822.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.61.2-61.2
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• 2014

A non-axisymmetric mass distribution of galactic structures including bulge (or bar) causes gas inflow from the disk to the nuclear region, including intense star formation within few hundred parsecs of galactic central. In order to investigate the relation between the ellipticity of the bulge and the presence of a nuclear starburst, we use a volume-limited sample of galaxies with Mr < -19.5 mag at 0.02 < z < 0.05 from the Sloan Digital Sky Survey Data Release 7. Total sample is 3252 spiral galaxies, which include nuclear starburst galaxies. We find that the occurrence of nuclear starbursts has a moderate correlation with bulge ellipticity of intermediate-type spiral galaxies (morphology classes Sab-Sb) in low galaxy number density environments and isolated regions where the distance between the target galaxies and the closest galaxies is relatively far. In high galaxy number density environments and interacting regions, close encounters and mergers between galaxies can cause gas inflow to the nuclear region even without the presence of non-axisymmetric bulges.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.546-551
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• 2001

Space Test Department at KARI(Korea Aerospace Research Institute) plans to carry out the GVT(Ground Vibration Test) for the KSR(Korea Sounding Rocket)-III FM(Flight Model) which is being developed by Space Technology R＆D Division. KSR-III will be an intermediate to the launch vehicle capable of carrying satellites to their orbits. GVT offers very important information to predict the behavior of KSR in its operation, and to develop the flight control and aerodynamic analysis. For development of test facilities, testing and analysis methods which can be used for the future test, Space Test Department has performed the GVT with KSR-II PFM(Proto-Flight Model) at Satellite Integration ＆ Test Center of KARl This paper discusses the procedures, techniques and the results of it. In this test, to simulate free-free condition, test object hung in the air by 4 bungee cords specially devised. The GVT was carried out using pure random excitation technique with MIMO(Multi-Input-Multi-Output) method with three electromagnetic shakers, and poly-reference parameter estimation was used to identify the modal parameters. As the result of the test, 11 mode shapes and modal parameters below 200㎐ were identified and compared with analytical results.

• ETRI Journal
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• v.37 no.6
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• pp.1077-1086
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• 2015

This paper presents a general-purpose design scheme of a filter bank (FB)-based radio frequency (RF) transceiver that operates across the entire ultra-high frequency (UHF) TV band from 470 MHz to 698 MHz and complies with the TV white space (TVWS) regulatory requirements. To this end, an intermediate frequency (IF) band-pass filter (BPF) with a sharp skirt characteristic is considered as a solution for handling the incoming signals from a baseband modem. Specifically, an FB-based BPF structure with four ceramic resonator filters that effectively rejects unwanted signals is proposed to extract a desired signal in the TV band. Achievable data rates of a cognitive radio system (CRS) employing the proposed FB-based RF transceiver at the application layer are investigated in both wired and wireless environments. The service coverage of the CRS network is measured according to several modulation and coding schemes (MCSs) of the CRS. The results show that the coverage of a wireless network in a nearly open area can be extended by more than 9.3 km in the TVWS. Experimental results also confirm that the proposed FB-based RF transceiver is adequate for utilization in TVWS applications.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.1
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• pp.38.1-38.1
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• 2014

A non-axisymmetric mass distribution in the galactic bulge (or bar) causes gas flow from the disk to the nuclear region, inducing intense star formation in the nucleus. We investigate the relation between the ellipticity of the bulge and the presence of a nuclear starburst by using a volume-limited sample of galaxies. We use 1,680 spiral galaxies with Mr < -19.5 at 0.02 <= z < 0.05 in the Sloan Digital Sky Survey Data Release 7. We find that the occurrence of nuclear starburst has a moderate correlation with bulge ellipticity in intermediate-type spiral galaxies (morphology classes Sab~Sb) in low galaxy number density environments. In high galaxy number density environments, close encounters and mergers between galaxies can cause gas inflow to the nuclear region even without the presence of non-axisymmetric bulges.