• Title/Summary/Keyword: time-domain analysis

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Atmospheric Correction Issues of Optical Imagery in Land Remote Sensing (육상 원격탐사에서 광학영상의 대기보정)

  • Lee, Kyu-Sung
    • Korean Journal of Remote Sensing
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    • v.35 no.6_3
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    • pp.1299-1312
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    • 2019
  • As land remote sensing applications are expanding to the extraction of quantitative information, the importance of atmospheric correction is increasing. Considering the difficulty of atmospheric correction for land images, it should be applied when it is necessary. The quantitative information extraction and time-series analysis on biophysical variables in land surfaces are two major applications that need atmospheric correction. Atmospheric aerosol content and column water vapor, which are very dynamic in spatial and temporal domain, are the most influential elements and obstacles in retrieving accurate surface reflectance. It is difficult to obtain aerosol and water vapor data that have suitable spatio-temporal scale for high- and medium-resolution multispectral imagery. Selection of atmospheric correction method should be based on the availability of appropriate aerosol and water vapor data. Most atmospheric correction of land imagery assumes the Lambertian surface, which is not the case for most natural surfaces. Further BRDF correction should be considered to remove or reduce the anisotropic effects caused by different sun and viewing angles. The atmospheric correction methods of optical imagery over land will be enhanced to meet the need of quantitative remote sensing. Further, imaging sensor system may include pertinent spectral bands that can help to extract atmospheric data simultaneously.

Development Framework for Tightly Coupled Linking of Patent and Scientific Paper (특허와 학술문헌 강결합 연계를 위한 프레임웍 개발)

  • Noh, Kyung-Ran;Kim, Wan-Jong;Kwon, Oh-Jin;Seo, Jinny
    • Proceedings of the Korea Contents Association Conference
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    • 2006.11a
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    • pp.702-705
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    • 2006
  • Because of explosive increase of information, it spends a lot of time to trace and analysis research trends during total R&D process. It has rapidly evolved from R&D or process development within a specific domain of knowledge to R&D or process development through knowledge convergency. To accept such a paradigm, it is necessary to convert dissemination system from a separate, standalone, and fragmentary information to highly coupled fusion information. Although there are several studies on knowledge flows between science and technology or technology and industry, it is difficult to analyse and utilize quantitatively to establish policy of Science, Technology, and Industry. The reason is the lack of information resource to analyse knowledge flow from science to industry. This paper intends to develop framework of highly coupled linking system between patent and scientific paper to utilize R&D, S&T policy, and industry policy.

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A Analysis on the Result of CE/CS Test on the KOMPSAT-I ETB (아리랑1호 위성 ETB의 전도성 전자파 환경 시험결과 분석)

  • 임성빈;천용식
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.12 no.2
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    • pp.184-192
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    • 2001
  • In this paper, we analyze the result of the conduced emission and susceptibility tests performed on the KOMPSAT-I ETB Platform. The ETB platform consists of the EM (Engineering Model) boxes developed to perform the electrical functional test. During the conducted emission test, we measured the instant waveform in time domain when each switch was turn on, and spectrum of the noise in the frequency range of 10 Hz up to100 MHz fur the steady state of the ETB. During the conducted susceptibility test, no malfunction and no serious damage of the electronic box were observed when a simulated noise waveform was applied to the DC power bus. The simulated waveform was obtained by adding the 6 dB-system margin to the worst case waveform measured from the conducted emission. This test was performed as co-development of the KOMPSAT-I with TRW in USA.

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Comparative Modeling and Molecular Dynamics Simulation of Substrate Binding in Human Fatty Acid Synthase: Enoyl Reductase and β-Ketoacyl Reductase Catalytic Domains

  • John, Arun;Umashankar, Vetrivel;Krishnakumar, Subramanian;Deepa, Perinkulam Ravi
    • Genomics & Informatics
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    • v.13 no.1
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    • pp.15-24
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    • 2015
  • Fatty acid synthase (FASN, EC 2.3.1.85), is a multi-enzyme dimer complex that plays a critical role in lipogenesis. This lipogenic enzyme has gained importance beyond its physiological role due to its implications in several clinical conditions-cancers, obesity, and diabetes. This has made FASN an attractive pharmacological target. Here, we have attempted to predict the theoretical models for the human enoyl reductase (ER) and ${\beta}$-ketoacyl reductase (KR) domains based on the porcine FASN crystal structure, which was the structurally closest template available at the time of this study. Comparative modeling methods were used for studying the structure-function relationships. Different validation studies revealed the predicted structures to be highly plausible. The respective substrates of ER and KR domains-namely, trans-butenoyl and ${\beta}$-ketobutyryl-were computationally docked into active sites using Glide in order to understand the probable binding mode. The molecular dynamics simulations of the apo and holo states of ER and KR showed stable backbone root mean square deviation trajectories with minimal deviation. Ramachandran plot analysis showed 96.0% of residues in the most favorable region for ER and 90.3% for the KR domain, respectively. Thus, the predicted models yielded significant insights into the substrate binding modes of the ER and KR catalytic domains and will aid in identifying novel chemical inhibitors of human FASN that target these domains.

Propagation Characteristic Analysis of Square and Gaussian Pulse Signals on the Microstrip Line (구형 및 가우시안 펄스신호의 마이크로스트립 선로상 전파특성 해석)

  • Park, Sun-Kuen;kim, Nam;Rhee, Sung-Yup;Choi, Jung-Hyun
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.7 no.5
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    • pp.384-394
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    • 1996
  • The propagation properties of square and Gaussian pulse signals on the microstrip line are investigated by using proper conventional models to meet the frequency range of a pulse, accuracy, and geometrical requirements of the microstrip line. Numerical integration technique which has its accuracy and is easily simulated, is used to obtain the time domain response of pulse signals. The dispersion of pulse signals is analyzed regarding to the relative permittivity $\varepsilon_r$, substrate height h, strip width w of the microstrip line and pulse width $\tau$ of signal pulse. The simulation results show that small relative permittivity and small rationale of w/h are advantageous for the dispersion of the pulse signals, and that pulse signals with small bandwidth cause smaller dispersion. The results of this paper are compatible to the trade-off determination of relative permittivity, substrate height, strip width and pulse width of signal pulse when a design of MIC and MMIC is necessary.

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Investigation of Motion of Single Point Moored Duct-type TCP System by Both Numerical and Experimental Method (수치 해석 및 모형실험을 이용한 수중 일점 계류식 조류발전 장치의 운동 성능 고찰)

  • JO, CHUL HEE;PARK, HONG JAE;CHO, BONG KUN;KIM, MYEONG JOO
    • Journal of Hydrogen and New Energy
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    • v.28 no.2
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    • pp.212-219
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    • 2017
  • As an environmental pollution and global warming due to an excessive carbon emission are intensified, the importance of renewable energy is in rise today. TCP (Tidal Current Power), one of the renewable energy sources, generates electricity by converting kinetic energy of current into rotational energy of turbine. Also the TCP has a great advantages of predictability and reliability. Because the generating power is proportional to cubic of stream velocity, amplifying current speed by applying duct is highly effective to increase the generating power. SPM (Single Point Mooring) can be applied for the weather vane with various current direction and also augments generating power of the system. In addition, simple installation and retrieval could be a merit of SPM system. By combining duct and SPM, TCP system for relatively low-speed-current and shallow water region can be feasible and economical. In this study, single point moored duct-type TCP system was designed and the motion of submerged structure was investigated in both numerical and experimental method. DNV wadam V4.8-1 and OrcaFlex 10.0a were used for the frequency and time domain motion analysis of system respectively. Duct model scaled by 0.05 of Froude conformity ratio and CWC (Circulate Water Channel) are used for experiment.

Structurally Conserved Aromaticity of Tyr249 and Phe264 in Helix 7 Is Important for Toxicity of the Bacillus thuringiensis Cry4Ba Toxin

  • Tiewsiri, Kasorn;Angsuthanasombat, Chanan
    • BMB Reports
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    • v.40 no.2
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    • pp.163-171
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    • 2007
  • Functional elements of the conserved helix 7 in the poreforming domain of the Bacillus thuringiensis Cry $\delta$- endotoxins have not yet been clearly identified. Here, we initially performed alanine substitutions of four highly conserved aromatic residues, $Trp^{243}$, $Phe^{246}$, $Tyr^{249}$ and $Phe^{264}$, in helix 7 of the Cry4Ba mosquito-larvicidal protein. All mutant toxins were overexpressed in Escherichia coli as 130-kDa protoxins at levels comparable to the wild-type. Bioassays against Stegomyia aegypti mosquito larvae revealed that only W243A, Y249A or F264A mutant toxins displayed a dramatic decrease in toxicity. Further mutagenic analysis showed that replacements with an aromatic residue particularly at $Tyr^{249}$ and $Phe^{264}$ still retained the high-level toxin activity. In addition, a nearly complete loss in larvicidal activity was found for Y249L/F264L or F264A/ Y249A double mutants, confirming the involvement in toxicity of both aromatic residues which face towards the same direction. Furthermore, the Y249L/F264L mutant was found to be structurally stable upon toxin solubilisation and trypsin digestion, albeit a small change in the circular dichroism spectrum. Altogether, the present study provides for the first time an insight into the highly conserved aromaticity of $Tyr^{249}$ and $Phe^{264}$ within helix 7 playing an important role in larvicidal activity of the Cry4Ba toxin.

Performance Review of a Cycloid Speed Reducer for Ship Transport Vehicles using FEM (유한요소해석을 이용한 선박수송차량용 사이클로이드 감속기의 성능 검토)

  • Kang, Hyung-Sun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.5
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    • pp.2061-2066
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    • 2011
  • A cycloid speed reducer is one of the rotational speed regulation devices of the machinery. A cycloid speed reducer has an advantage of transmitting high torque, but is known to be unsuitable for high speed rotation. However, it is almost impossible in an analytical method to find a use limit speed when installing such a speed reducer in a 200ton loading transporter. In this research the cycloid reducer was simulated to get its performance depending on friction energy loss in time domain by using by LS-DYNA. The maximum torque of the cycloid speed reducer is 3.5ton-m, so the comparison of analysis results between a case of 60rpm rotation and a case of 162rpm rotation with such a torque showed the following results. In the case of 60rpm rotation, the maximum stress appearing in the RV gear and the pin gear was 463MPa and 507MPa. Lost power due to friction was 50kW; In the case of 162rpm rotation, the maximum stress appearing in the RV gear and the pin gear was 550MPa and 538MPa. Lost power due to friction was 175kW, which was shown to be almost impossible to use.

Analysis of Saturation and Ground Water Level at Embankment by TDR Sensor (TDR센서를 이용한 제방의 포화도 및 지하수위 해석)

  • Kim, Ki-Young;Han, Heui-Soo;Lee, Jae-Ho;Park, Min-Cheol
    • Journal of the Korean Geotechnical Society
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    • v.27 no.2
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    • pp.63-72
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    • 2011
  • The measured ground water behavior by TDR (time domain reflectometer) sensors were analyzed by the data filtering technique such as moving average method and Fourier transform, and the ground water level and unsaturated zone were tried to be determined numerically. At first, the variation of TDR data according to the saturation degree was measured by lab test, which is translated as a function of saturation degree. Then, changes of ground water level and lateral seepage in field conditions were simulated using acrylic pipe, and the measured data were analyzed to make calibration curve. Furthermore, TDR sensors were installed into the in-situ embankment to insure the field application. The saturation degree, unsaturated and dried zones were determined from the measured data.

An Analysis of the Content Elements and Inquiry Activities in the Revised "Wise Life" Curriculum 2007 (2007년 개정 슬기로운 생활 교육 과정의 내용 요소 및 탐구 활동 분석)

  • Park, Jae-Keun;Baik, Hyun-Jung
    • Journal of Korean Elementary Science Education
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    • v.28 no.1
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    • pp.55-66
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    • 2009
  • The purpose of this study is to assist understanding the integrated subjects and to obtain implications required on the actual operation of curriculum by analyzing content elements and basic inquiry activities in the revised "wise lift" curriculum 2007. The result of this study is as follows. First, the formation of elements in contents of "wise life" deals with the passage of time based on changing seasons, myself and family in the 1st grade and the concept of space based on home and a village in the 2nd grade. Six main subjects and twelve activity subjects are presented per each grade. Second, number of activity subjects and content elements are reduced as compared with 7th curriculum so that the responsibility of operating classes based on activities is reduced and the purpose of rationalizing contents is somewhat fulfilled. Third, eliminating a relevant domains decisively when presenting the activity subjects assures the identification and purpose as the integrated subject focused on inquiry activities. Fourth, the result of analyzing the course-relevance on content elements shows that the allotment per each domain and course is less considered but the relevance of social studies is higher regardless of non-course characteristics as the integrated subject. Fifth, according to the component ratio of basic inquiry activities, 'Observing' and 'Debating' were presented as the most essential activities, and 'Measuring' and 'Making' were relatively low. By considering characteristics of course requiring balanced and various experiences of inquiry activities, additional discussions are required on appropriateness of the component ratio. Sixth, 'Observing' was increased and 'Debating' and 'Making' were decreased on the main activities in this revised curriculum as compared with 7th curriculum.

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