• Title/Summary/Keyword: Sun-Acquisition

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The Effect of Self-esteem on Operation Performance: Perspective on Air Navigation System Operator in Airport (공항 항행시스템 운영자 관점에서 자존감이 운영성과에 미치는 영향)

  • Song, Jong-sun;Lee, Yung-kil
    • Journal of Advanced Navigation Technology
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    • v.20 no.6
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    • pp.544-555
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    • 2016
  • Organizations of airport continue to invest heavily in the acquisition of self-esteem. Because, it is that self-esteem will become more productive. In this article, We verify to influence in the operation performance by the air navigation system and moderated effect of self-esteem. A survey of Incheon International Airport and Gimpo International Airport was conducted to better understand the factors that affect air navigation system to explain operation performance of airport perspective on air navigation system operator. The findings indicate that the positively moderated self-esteem affects operation performance of airports. We also confirmed that air navigation policy, maintenance, and promotion activities of air navigation system factors are affecting the operation performance of airports. The results of this study suggest that self-esteem could be the basis for a strong measurement tool to evaluate whether self-esteem in a given organization of airport are meeting enhancement of operation performance.

DEVELOPMENT OF GOCI/COMS DATA PROCESSING SYSTEM

  • Ahn, Yu-Hwan;Shanmugam, Palanisamy;Han, Hee-Jeong;Ryu, Joo-Hyung
    • Proceedings of the KSRS Conference
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    • v.1
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    • pp.90-93
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    • 2006
  • The first Geostationary Ocean Color Imager (GOCI) onboard its Communication Ocean and Meteorological Satellite (COMS) is scheduled for launch in 2008. GOCI includes the eight visible-to-near-infrared (NIR) bands, 0.5km pixel resolution, and a coverage region of 2500 ${\times}$ 2500km centered at 36N and 130E. GOCI has had the scope of its objectives broadened to understand the role of the oceans and ocean productivity in the climate system, biogeochemical variables, geological and biological response to physical dynamics and to detect and monitor toxic algal blooms of notable extension through observations of ocean color. The special feature with GOCI is that like MODIS, MERIS and GLI, it will include the band triplets 660-680-745 for the measurements of sun-induced chlorophyll-a fluorescence signal from the ocean. The GOCI will provide SeaWiFS quality observations with frequencies of image acquisition 8 times during daytime and 2 times during nighttime. With all the above features, GOCI is considered to be a remote sensing tool with great potential to contribute to better understanding of coastal oceanic ecosystem dynamics and processes by addressing environmental features in a multidisciplinary way. To achieve the objectives of the GOCI mission, we develop the GOCI Data Processing System (GDPS) which integrates all necessary basic and advanced techniques to process the GOCI data and deliver the desired biological and geophysical products to its user community. Several useful ocean parameters estimated by in-water and other optical algorithms included in the GDPS will be used for monitoring the ocean environment of Korea and neighbouring countries and input into the models for climate change prediction.

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Cramer-Rao Lower Bound of Effective Carrier-to-noise Power Ratio Estimation for a GPS L1 C/A Signal under Band-limited White Noise Jamming Environments (대역제한 백색잡음 재밍환경에서 GPS L1 C/A 신호를 위한 유효 반송파 대 잡음 전력비 추정치의 CRLB)

  • Yoo, Seungsoo;Yeom, Dong-Jin;Jee, Gyu-In;Kim, Sun Yong
    • Journal of Institute of Control, Robotics and Systems
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    • v.20 no.8
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    • pp.890-894
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    • 2014
  • In this paper, we derive the CRLB (Cramer-Rao Lower Bound) of effective carrier-to-noise power ratio ($C/N_0$) estimation for a GPS (Global Positioning System) L1 C/A (Coarse/Acquisition) signal under band-limited white noise jamming environments. The quality of a received GPS signal is commonly described in terms of its $C/N_0$, implying that the noise is white and thus can be described by scalar noise density. However, if some intentional interference is received to a victim GPS receiver, then the $C/N_0$ is no longer the efficacious performance indicator. The correct and straightforward measurement to analyze the receiving situation is the effective $C/N_0$. In this paper, we consider a band-limited white noise jamming whose bandwidth is 2MHz and is the same as one of the first null-to-null bandwidth of the GPS L1 C/A signal.

Design of an Efficient Coarse Frequency Estimator Using a Serial Correlator for DVB-S2 (직렬 상관기를 이용한 디지털 위성방송 주파수 추정회로 설계)

  • Yun, Hyoung-Jin;SunWoo, Myung-Hoon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.4A
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    • pp.434-439
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    • 2008
  • This paper proposes an efficient coarse frequency synchronizer for digital video broadcasting - second generation (DVB-S2). The input signal requirement of acquisition range for coarse frequency estimator in the DVB-S2 is around ${\pm}1.5625Mhz$, which corresponds to 6.25% of the symbol rate at 25Mbaud. At the process of analyzing the robust algorithm among data-aided approaches, we find that the Luise & Reggiannini (L&R) algorithm is the most promising one for coarse frequency estimation with respect to estimation performance and complexity. However, it requires many multipliers and adders to compute output values of correlators. We propose an efficient architecture identifying the serial correlator with the buffer and multiplexers. The proposed coarse frequency synchronizer can reduce the hardware complexity about 92% of the direct implementation. The proposed architecture has been implemented and verified on the Xilinx Virtex II FPGA.

A Novel Carrier-to-noise Power Ratio Estimation Scheme with Low Complexity for GNSS Receivers (GNSS 수신기를 위한 낮은 복잡도를 갖는 새로운 반송파 대 잡음 전력비 추정기법)

  • Yoo, Seungsoo;Baek, Jeehyeon;Yeom, Dong-Jin;Jee, Gyu-In;Kim, Sun Yong
    • Journal of Institute of Control, Robotics and Systems
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    • v.20 no.7
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    • pp.767-773
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    • 2014
  • The carrier-to-noise power ratio is a key parameter for determining the reliability of PVT (Position, Velocity, and Time) solutions which are obtained by a GNSS (Global Navigation Satellite System) receiver. It is also used for locking a tracking loop, deciding the re-acquisition process, and processing advanced navigation in the receiver subsystem. The representative carrier-to-noise power ratio estimation schemes are the narrowband-wideband power ratio method (NW), the MM (Moment Method), and Beaulieu's method (BL). The NW scheme is the most classical one for commercial GNSS receivers. It is often used as an authoritative benchmark for assessing carrier-to-noise power estimation schemes. The MM scheme is the least biased solution among them, and the BL scheme is a simpler scheme than the MM scheme. This paper focuses on the less biased estimation with low complexity when the residual phase noise remains, then proposes a novel carrier-to-noise power ratio estimation scheme with low complexity for GNSS receivers. The asymptotic bias of the proposed scheme is derived and compared with others, and the simulation results demonstrate that the complexity of the proposed scheme is lowest among them, while the estimation performance of the proposed scheme is similar to those of the BL and MM schemes in normal and high gained reception environments.

Molecular and biochemical characterization of hemoglobinase, a cysteine proteinase, in Paragonimus westermani

  • Choi Joon-Hyuck;Lee Jae-Hyuk;Yu Hak-Sun;Jeong Hae-Jin;Kim Jin;Hong Yeon-Chul;Kong Hyun-Hee;Chung Dong-Il
    • Parasites, Hosts and Diseases
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    • v.44 no.3
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    • pp.187-196
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    • 2006
  • The mammalian trematode Paragonimus westermani is a typical digenetic parasite, which can cause paragonimiasis in humans. Host tissues and blood cells are important sources of nutrients for development, growth and reproduction of P. westermani. In this study, a cDNA clone encoding a 47 kDa hemoglobinase of P. westermani was characterized by sequencing analysis, and its localization was investigated immunohistochemically. The phylogenetic tree prepared based on the hemoglobinase gene showed high homology with hemoglobinases of Fasciola hepatica and Schistosoma spp. Moreover, recombinant P. westermani hemoglobinase degradaded human hemoglobin at acidic pH (from 3.0 to 5.5) and its activity was almost completely inhibited by E-64, a cysteine proteinase inhibitor. Immunohistochemical studies showed that P. westermani hemoglobinase was localized in the epithelium of the adult worm intestine implying that the protein has a specific function. These observations suggest that hemoglobinase may act as a digestive enzyme for acquisition of nutrients from host hemoglobin. Further investigations may provide insights into hemoglobin catabolism in P. westermani.

Link Margin Analysis on Telemetry for KSLV-I Launch (KSLV-1 발사를 위한 원격측정신호 Link Margin 분석)

  • Oh, Chang-Yul;Lee, Sung-Hee;Kim, Dong-Hyun;Kwon, Sun-Ho
    • Aerospace Engineering and Technology
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    • v.8 no.2
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    • pp.105-112
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    • 2009
  • Telemetry data is very important for the Launch Mission and Flight Safety Control during the Space Launch. In Naro Space Center, several telemetry stations such as a small station in the NARO space center, two stations in Jeju and a downrange station on a ship are deployed for the stable acquisition/receiving of the telemetry signals. In this paper, the Link Margin and Reliability for the telemetry are analyzed to evaluate the probability of the signal receiving of each station. Even though the proper analysis is to using the on-board EIRP(Effective Isotropic Radiation Power) values in the direction of the ground station considering the predicted flight trajectory and the locations of the stations, the global EIRP of 95% spatial coverage has been used for the analysis, due to the limitation of the available data.

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Functional Prediction of Imprinted Genes in Chicken Based on a Mammalian Comparative Expression Network

  • Kim, Hyo-Young;Moon, Sun-Jin;Kim, Hee-Bal
    • Genomics & Informatics
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    • v.6 no.1
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    • pp.32-35
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    • 2008
  • Little evidence supports the existence of imprinted genes in chicken. Imprinted genes are thought to be intimately connected with the acquisition of parental resources in mammals; thus, the predicted lack of this type of gene in chicken is not surprising, given that they leave their offspring to their own heritance after conception. In this study, we identified several imprinted genes and their orthologs in human, mouse, and zebrafish, including 30 previously identified human and mouse imprinted genes. Next, using the HomoloGene database, we identified six orthologous genes in human, mouse, and chicken; however, no orthologs were identified for SLC22A18, and mouse Ppp1r9a was not included in the HomoloGene database. Thus, from our analysis, four candidate chicken imprinted genes (IGF2, UBE3A, PHLDA2, and GRB10) were identified. To expand our analysis, zebrafish was included, but no probe ID for UBE3A exists in this species. Thus, ultimately, three candidate imprinted genes (IGF2, PHLDA2, and GRB10) in chicken were identified. GRB10 was not significant in chicken and zebrafish based on the Wilcoxon-Mann-Whitney test, whereas a weak correlation between PHLDA2 in chicken and human was identified from the Spearman's rank correlation coefficient. Significant associations between human, mouse, chicken, and zebrafish were found for IGF2 and GRB10 using the Friedman's test. Based on our results, IGF2, PHLDA2, and GRB10 are candidate imprinted genes in chicken. Importantly, the strongest candidate was PHLDA2.

Kinematic Analysis of a Legged Walking Robot Based on Four-bar Linkage and Jansen Mechanism (4절 링크 이론과 얀센 메커니즘을 기반으로 한 보행 로봇의 운동학 해석)

  • Kim, Sun-Wook;Kim, Dong-Hun
    • Journal of the Korean Institute of Intelligent Systems
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    • v.21 no.2
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    • pp.159-164
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    • 2011
  • In this study, a crab robot is implemented in H/W based on four-bar linkage mechanism and Jansen mechanism, and its kinematics is analysed. A vision camera is attached to the mechanism, which makes the proposed robot a kind of biologically inspired robot for image acquisition. Three ultrasonic sensors are adopted for obstacle avoidance. In addition, the biologically inspired robot can achieve the mission appointed by a programmer outside, based on RF and Blue-tooth communication module. For the design and implementation of a crab robot, it is need to get joint variable, a foot point, and their relation. Thus, the proposed kinematic analysis is very important process for the design and implementation of legged robots.

Observation of the Ground Subsidence in the Abandoned Gaeun Coal Mining Area using JERS-1 SAR (JERS-1 SAR를 이용한 가은 폐탄광 지역 지반침하 관측)

  • Jung Hahn Chul;Kim Sang-Wan;Kim Bok Chul;Min Kyung Duck;Won Joong-Sun
    • Economic and Environmental Geology
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    • v.37 no.5
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    • pp.509-519
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    • 2004
  • The ground subsidence that occurred in the abandoned coal mining area, Gaeun, Korea, was observed using 25 JERS-1 SAR interferograms from November 1992 to October 1998. We carried out measurements on a subset of image pixels corresponding to point-wise stable reflectors(PS: permanent scatterer) by exploiting a long temporal series of interferometric phases and compared it with the distribution map of in situ examined crack level. PSs could be identified by means of amplitude dispersion index and coherence of the interferograms and the density of PS was much higher in an urban area than in a mountainous region. The measured subsidence rate represented the average velocity in a period of image acquisition and excluded complex nonlinear displacements such as an abrupt collapse. The mean line-of-sight velocity in the study area is 0.19cm/yr and the estimation error is 0.18cm/yr. The center of the abandoned Gaeun coal mine(0.49cm/yr) and the area opposite Gaeun station(1.66cm/yr) were observed as the most highly subsiding areas.