• Title/Summary/Keyword: non-stationary

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Correlation between the Position Accuracy of the Network RTK Rover and Quality Indicator of Various Performance Analysis Method (Network RTK 품질 분석 방법론별 성능 지표와 사용자 항법 정확도의 상관성)

  • Lim, Cheol-soon;Park, Byung-woon;Heo, Moon-beom
    • Journal of Advanced Navigation Technology
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    • v.22 no.5
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    • pp.375-383
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    • 2018
  • In order to apply the Network RTK (real time kinematics) technology, which has been used for positioning of stationary points, to the navigation of vehicles, its infrastructure should provide correction data with a quality indicator that can show the expected accuracy in real time. In this paper, we analyzed various indicator generation algorithms such as I95 (ionospheric index 95) / G95 (geodetic index 95), SBI (semivariance based index) and RIU (residual interpolation uncertainty). We also applied them to the raw observables from the reference stations of National Geographic Information Institute and VRS (virtual reference station) users, and then examined its feasibility to be used as a real-time performance index of the Network RTK rover. 24 hour data analysis shows that the RIU index, which can represent the non-linearty of the correction, has the strongest correlation with the Network RTK rover accuracy. Therefore, RIU index is expected to be used as a real-time performance index of the Network RTK rover.

Transfiguration in Fashion Design - Focused on Stationary Space Isolated from the Body - (탈(脫)신체적 패션 디자인에 관한 고찰 - 몸과 유리된 고정 공간의 형성을 중심으로 -)

  • Yim, Eun-Hyuk
    • Journal of the Korean Society of Costume
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    • v.57 no.4 s.113
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    • pp.70-80
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    • 2007
  • Clothes and human body are inseparably related. Aesthetic consciousness of the body determines the form of clothing, reflecting the time and culture as well as the individual and society. Clothes can even reorganize the meaning of the body, while transcending their instrumental functions of protecting, expanding and deforming the body. Using 'body' to analyze the clothing form, my study develops a framework by which to classify transfiguration in fashion design. In order to inquire tile formative style and aesthetic values expressed in transfiguration in fashion, my study examines subjects from the discourse on the body to the fashion collections of the late 20th and 21st century. The results of the study are as follows. Transfiguration signifies absence of body which questions the three dimensional construction of the body in more conventional clothing system. Transfiguration is expressed in non-figural forms which implies metaphorical plasticity and abstract extensity. Transfiguration in fashion stresses a will-to-form rather than mere bodily proportion and structure, which explores trans-extensity that goes beyond the boundary of the body. Ultimately, this phase also betrays the correspondence between signifiant and $signifi\acute{e}$ in sartorial convention. Aesthetic ideal of the body is visualized in the form of a dress. Some clothes prioritize the body, particularly the feminine bodily curves, while others focus on the clothing itself as abstract and sculptural forms. Fashion continues to explore forms and images that transcend the traditional representations of the clothed body. As a type of intimate architecture, fashion always mediates the dialogue between clothes and body, or fashion and figure. My study suggests a framework to analyze bodily representation in transfiguration in fashion, focusing on the relationship between the clothes and body.

An Efficient Processing of Continuous Range Queries on High-Dimensional Spatial Data (고차원 공간 데이터를 위한 연속 범위 질의의 효율적인 처리)

  • Jang, Su-Min;Yoo, Jae-Soo
    • Journal of KIISE:Computing Practices and Letters
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    • v.13 no.6
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    • pp.397-401
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    • 2007
  • Recent applications on continuous queries on moving objects are extended quickly to various parts. These applications need not only 2-dimensional space data but also high-dimensional space data. If we use previous index for overlapped continuous range queries on high-dimensional space data, as the number of continuous range queries on a large number of moving objects becomes larger, their performance degrades significantly. We focus on stationary queries, non-exponential increase of storage cost and efficient processing time for large data sets. In this paper, to solve these problems, we present a novel query indexing method, denoted as PAB(Projected Attribute Bit)-based query index. We transfer information of high-dimensional continuous range query on each axis into one-dimensional bit lists by projecting technique. Also proposed query index supports incremental update for efficient query processing. Through various experiments, we show that our method outperforms the CES(containment-encoded squares)-based indexing method which is one of the most recent research.

Robust Blind Source Separation to Noisy Environment For Speech Recognition in Car (차량용 음성인식을 위한 주변잡음에 강건한 브라인드 음원분리)

  • Kim, Hyun-Tae;Park, Jang-Sik
    • The Journal of the Korea Contents Association
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    • v.6 no.12
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    • pp.89-95
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    • 2006
  • The performance of blind source separation(BSS) using independent component analysis (ICA) declines significantly in a reverberant environment. A post-processing method proposed in this paper was designed to remove the residual component precisely. The proposed method used modified NLMS(normalized least mean square) filter in frequency domain, to estimate cross-talk path that causes residual cross-talk components. Residual cross-talk components in one channel is correspond to direct components in another channel. Therefore, we can estimate cross-talk path using another channel input signals from adaptive filter. Step size is normalized by input signal power in conventional NLMS filter, but it is normalized by sum of input signal power and error signal power in modified NLMS filter. By using this method, we can prevent misadjustment of filter weights. The estimated residual cross-talk components are subtracted by non-stationary spectral subtraction. The computer simulation results using speech signals show that the proposed method improves the noise reduction ratio(NRR) by approximately 3dB on conventional FDICA.

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Finite Element Modal Analysis of a Spinning Flexible Disk-Spindle System Supported by Hydro Dynamic Bearings and Flexible Supporting Structures In a HDD (유연한 지지 구조와 유체 동압 베어링으로 지지되는 HDD의 회전 유연 디스크-스핀들 시스템에 대한 유한 요소 고유 진동 해석)

  • 한재혁;장건희
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2003.11a
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    • pp.572-578
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    • 2003
  • The free vibration of a spinning flexible disk-spindle system supported by hydro dynamic bearings in a HDD is analyzed by FEM. The spinning flexible disk is described using Kirchhoff plate theory and von Karman non-linear strain, and its rigid body motion is also considered. It is discretized by annular sector element. The rotating spindle which includes the clamp, hub, permanent magnet and yoke, is modeled by Timoshenko beam including the gyroscopic effect. The flexible supporting structure with a complex shape which includes stator core, housing, base plate, sleeve and thrust pad is modeled by using a 4-node tetrahedron element with rotational degrees of freedom to satisfy the geometric compatibility. The dynamic coefficients of HDB are calculated from the HDB analysis program, which solves the perturbed Raynolds equation using FEM. Introducing the virtual nodes and the rigid link constraints defined in the center of HDB, beam elements of the shaft are connected to the solid elements of the sleeve and thrust pad through the spring and damper element. The global matrix equation obtained by assembling the finite element equations of each substructure is transformed to the state-space matrix-vector equation, and the associated eigenvalue problem is solved by using the restarted Arnoldi iteration method. The validity of this research is verified by comparing the numerical results of the natural frequencies with the experimental ones. Also the effect of supporting structures to the natural modes of the total HDD system is rigorously analyzed.

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Web-Based Data Processing and Model Linkage Techniques for Agricultural Water-Resource Analysis (농촌유역 물순환 해석을 위한 웹기반 자료 전처리 및 모형 연계 기법 개발)

  • Park, Jihoon;Kang, Moon Seong;Song, Jung-Hun;Jun, Sang Min;Kim, Kyeung;Ryu, Jeong Hoon
    • Journal of The Korean Society of Agricultural Engineers
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    • v.57 no.5
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    • pp.101-111
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    • 2015
  • Establishment of appropriate data in certain formats is essential for agricultural water cycle analysis, which involves complex interactions and uncertainties such as climate change, social & economic change, and watershed environmental change. The main objective of this study was to develop web-based Data processing and Model linkage Techniques for Agricultural Water-Resource analysis (AWR-DMT). The developed techniques consisted of database development, data processing technique, and model linkage technique. The watershed of this study was the upper Cheongmi stream and Geunsam-Ri. The database was constructed using MS SQL with data code, watershed characteristics, reservoir information, weather station information, meteorological data, processed data, hydrological data, and paddy field information. The AWR-DMT was developed using Python. Processing technique generated probable rainfall data using non-stationary frequency analysis and evapotranspiration data. Model linkage technique built input data for agricultural watershed models, such as the TANK and Agricultural Watershed Supply (AWS). This study might be considered to contribute to the development of intelligent watercycle analysis by developing data processing and model linkage techniques for agricultural water-resource analysis.

A Fast Multiresolution Motion Estimation Algorithm in the Adaptive Wavelet Transform Domain (적응적 웨이브렛 영역에서의 고속의 다해상도 움직임 예측방법)

  • 신종홍;김상준;지인호
    • Journal of Broadcast Engineering
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    • v.7 no.1
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    • pp.55-65
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    • 2002
  • Wavelet transform has recently emerged as a promising technique for video processing applications due to its flexibility in representing non-stationary video signals. Motion estimation which uses wavelet transform of octave band division method is applied In many places but if motion estimation error happens in the lowest frequency band. motion estimation error is accumulated by next time strep and there has the Problem that time and the data amount that are cost In calculation at each steps are increased. On the other hand. wavelet packet that achieved the best image quality in a given bit rate from a rate-distortion sense is suggested. But, this method has the disadvantage of time costs on designing wavelet packet. In order to solve this problem we solved this problem by introducing Top_down method. But we did not find the optimum solution in a given butt rate. That image variance can represent image complexity is considered in this paper. In this paper. we propose a fast multiresolution motion estimation scheme based on the adaptive wavelet transform for video compression.

Time Series Analysis and Forecasting of Electrical Conductivity in Coastal Aquifers (연안암반대수층의 해수침투경향성 파악을 위한 전기전도도 시계열 분석과 예측)

  • Ju, Jeong-Woung;Yeo, In Wook
    • Economic and Environmental Geology
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    • v.50 no.4
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    • pp.267-276
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    • 2017
  • Seawater intrusion into coastal fractured rock aquifer, resulting in groundwater contamination, is of serious concern in coastal areas of Jeolla Namdo, Korea, which heavily depends on groundwater resources. Time series analysis and forecasting were carried out to analyze and predict EC which is a major indicator of seawater intrusion. Two time series models of autoregressive integrated moving average (ARIMA) and seasonal autoregressive integrated moving average (SARIMA) were tested for suggesting appropriate time series model. Time series data of EC measured over one year showed a increasing trend with short periodic fluctuations, due to tidal effect and pumping, which indicated that EC time series data tended to be non-stationary. SARIMA model was found better fitted to observed EC than any other time series model. Time series analysis and modeling was found to be a useful tool to analyze EC at coastal fractured rock aquifer subject to seawater intrusion.

Characterization of V/TiO2 Catalysts for Selective Reduction (V/TiO2 촉매의 선택적 촉매 환원 반응특성 연구)

  • Lee, Sang-Jin;Hong, Sung-Chang
    • Applied Chemistry for Engineering
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    • v.19 no.5
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    • pp.512-518
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    • 2008
  • The present work studied the selective catalytic reduction (SCR) of NO to $N_2$ by $NH_3$ over $V/TiO_2$ focusing on NOx control for the stationary sources. The SCR process depends mainly on the catalyst performance. The reaction characteristics of SCR with $V/TiO_2$ catalysts were closely examined at low and high temperature. In addition, adsorption and desorption characteristics of the reactants on the catalyst surface were investigated with ammonia. Seven different $TiO_2$ supports containing the same loading of vanadia were packed in a fixed bed reactor respectively. The interaction between $TiO_2$ and vanadia would form various non-stoichiometric vanadium oxides, and showed different reaction activities. There were optimum calcination temperatures for each samples, indicating different reactivity. It was finally found from the $NH_3-TPD$ test that the SCR activity was nothing to do with $NH_3$ adsorption amount.

Wavelet Analysis of Visualized Image (가시화 영상의 웨이브렛 해석)

  • Park, Young-Sik;Kim, Okug-Gyu
    • Journal of the Institute of Convergence Signal Processing
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    • v.8 no.3
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    • pp.143-148
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    • 2007
  • The many studies have been proceeding to express accurately the feature of a sudden signal and a uncertain system in the image processing field. It is well know that Fourier Transform is widely used for frequency analysis of any signal. However, The frequency transform domain is not used for expressing the sudden signal change and non-stationary signal at the time-axis by this method. This paper describes of image analysis by discrete wavelet transform. Wavelet modulus maxima on transformed plane gives the Lipschitz exponent expression, which is useful to examine the characteristics of signal or the edge of an image. It is possible to reconstruct the original image only using the few maxima points. The fractal analysis is applied as an examples. The visualized image of oil flow on a ship model is analyzed. The fractal variable is obtained by the maxima analysis and the good results on the exprement is obtained by the visualized image analysis.

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