Weather records from recent years performed better than analogue years when merging with real-time weather measurements for dynamic within-season predictions of rainfed maize yield

A multipath is a major error source in bridge deformation monitoring and the key to achieving millimeter-level monitoring. Although the traditional MHM (multipath hemispherical map) algorithm can be applied to multipath mitigation in real-time scenarios, accuracy needs to be further improved due to the influence of observation noise and the multipath differences between different satellites. Aiming at the insufficiency of MHM in dealing with the adverse impact of observation noise, we proposed the MHM_V model, based on Variational Mode Decomposition (VMD) and the MHM algorithm. Utilizing the VMD algorithm to extract the multipath from single-difference (SD) residuals, and according to the principle of the closest elevation and azimuth, the original observation of carrier phase in the few days following the implementation are corrected to mitigate the influence of the multipath. The MHM_V model proposed in this paper is verified and compared with the traditional MHM algorithm by using the observed data of the Forth Road Bridge with a seven day and 10 s sampling rate. The results show that the correlation coefficient of the multipath on two adjacent days was increased by about 10% after residual denoising with the VMD algorithm; the standard deviations of residual error in the L1/L2 frequencies were improved by 37.8% and 40.7%, respectively, which were better than the scores of 26.1% and 31.0% for the MHM algorithm. Taking a ratio equal to three as the threshold value, the fixed success rates of ambiguity were 88.0% without multipath mitigation and 99.4% after mitigating the multipath with MHM_V. The MHM_V algorithm can effectively improve the success rate, reliability, and convergence rate of ambiguity resolution in a bridge multipath environment and perform better than the MHM algorithm.

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Evaluation of IMERG Level-3 Products in Depicting the July to October Rainfall over Taiwan: Typhoon Versus Non-Typhoon

Remote Sensing ◽

10.3390/rs13040622 ◽

2021 ◽

Vol 13 (4) ◽

pp. 622

Author(s):

Wan-Ru Huang ◽

Pin-Yi Liu ◽

Ya-Hui Chang ◽

Cheng-An Lee

Keyword(s):

Real Time ◽

Tropical Rainfall Measuring Mission ◽

Temporal Variations ◽

Rain Gauge ◽

Advantages And Disadvantages ◽

Level 3 ◽

Spatio Temporal ◽

Typhoon Season ◽

Early Late ◽

Better Than

This study assesses the performance of satellite precipitation products (SPPs) from the latest version, V06B, Integrated Multi-satellitE Retrievals for Global Precipitation Mission (IMERG) Level-3 (including early, late, and final runs), in depicting the characteristics of typhoon season (July to October) rainfall over Taiwan within the period of 2000–2018. The early and late runs are near-real-time SPPs, while final run is post-real-time SPP adjusted by monthly rain gauge data. The latency of early, late, and final runs is approximately 4 h, 14 h, and 3.5 months, respectively, after the observation. Analyses focus on the seasonal mean, daily variation, and interannual variation of typhoon-related (TC) and non-typhoon-related (non-TC) rainfall. Using local rain-gauge observations as a reference for evaluation, our results show that all IMERG products capture the spatio-temporal variations of TC rainfall better than those of non-TC rainfall. Among SPPs, the final run performs better than the late run, which is slightly better than the early run for most of the features assessed for both TC and non-TC rainfall. Despite these differences, all IMERG products outperform the frequently used Tropical Rainfall Measuring Mission 3B42 v7 (TRMM7) for the illustration of the spatio-temporal characteristics of TC rainfall in Taiwan. In contrast, for the non-TC rainfall, the final run performs notably better relative to TRMM7, while the early and late runs showed only slight improvement. These findings highlight the advantages and disadvantages of using IMERG products for studying or monitoring typhoon season rainfall in Taiwan.

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Modified Posicast Control Design Method Based on the Parameters of a Fractional Order System

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.4049549 ◽

2021 ◽

Vol 143 (4) ◽

Author(s):

Erhan Yumuk ◽

Müjde Güzelkaya ◽

İbrahim Eksin

Keyword(s):

Real Time ◽

Fractional Order ◽

Control Method ◽

Design Method ◽

Order System ◽

Half Cycle ◽

Empirical Formulas ◽

Real Time System ◽

Novel Design ◽

Better Than

Abstract In this study, a novel design method for half-cycle and modified posicast controller structures is proposed for a class of the fractional order systems. In this method, all required design variable values, namely, the input step magnitudes and their application times are obtained as functions of fractional system parameters. Moreover, empirical formulas are obtained for the overshoot values of the compensated system with half-cycle and modified posicast controllers designed utilizing this method. The proposed design methodology has been tested via simulations and ball balancing real-time system. It is observed that the derived formulas are in coherence with outcomes of the simulation and real-time application. Furthermore, the performance of modified posicast controller designed using proposed method is much better than other posicast control method.

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Aerosol optical depth in the European Brewer Network

10.5194/acp-2017-1003 ◽

2017 ◽

Author(s):

Javier López-Solano ◽

Alberto Redondas ◽

Thomas Carlund ◽

Juan J. Rodriguez-Franco ◽

Henri Diémoz ◽

...

Keyword(s):

Real Time ◽

Aerosol Optical Depth ◽

Optical Depth ◽

Temporal Variability ◽

Input Data ◽

Spatial And Temporal Variability ◽

Ultraviolet Range ◽

Using Data ◽

Better Than

Abstract. The high spatial and temporal variability of aerosols make networks capable of measuring their properties in near real time of high scientific interest. In this work we present and discuss results of an aerosol optical depth algorithm to be used in the European Brewer Network, which provides data in near real time of more than 30 spectrophotometers located from Tamanrasset (Algeria) to Kangerlussuaq (Greenland). Using data from the Brewer Intercomparison Campaigns in the years 2013 and 2015, and the period in between, plus comparisons with Cimel sunphotometers and UVPFR instruments, we check the precision, stability, and uncertainty of the Brewer AOD in the ultraviolet range from 300 to 320 nm. Our results show a precision better than 0.01, an uncertainty of less than 0.05, and a stability similar to that of the ozone measurements for well-maintained instruments. We also discuss future improvements to our algorithm with respect to the input data, their processing, and the characterization of the Brewer instruments for the measurement of aerosols.

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A Real-Time Structure of Attitude Algorithm for High Dynamic Bodies

Journal of Control Science and Engineering ◽

10.1155/2017/9542423 ◽

2017 ◽

Vol 2017 ◽

pp. 1-8

Author(s):

Xingcheng Li ◽

Shuangbiao Zhang

Keyword(s):

Real Time ◽

Time Structure ◽

Flow Diagram ◽

The Real ◽

Time Problem ◽

Conventional Structure ◽

High Dynamic ◽

Two Stages ◽

Better Than ◽

Attitude Matrix

To solve the real-time problem of attitude algorithm for high dynamic bodies, a real-time structure of attitude algorithm is developed by analyzing the conventional structure that has two stages, and a flow diagram of a real-time structure for a Matlab program is provided in detail. During the update of the attitude matrix, the real-time structure saves every element of attitude matrix in minor loop in real time and updates the next attitude matrix based on the previous matrix every subsample time. Thus, the real-time structure avoids lowering updating frequency, though the multisubsample algorithms are used. Simulation and analysis show that the real-time structure of attitude algorithm is better than the conventional structure due to short update time of attitude matrix and small drifting error, and it is more appropriate for high dynamic bodies.

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Depth-averaged instantaneous currents in a tidally dominated shelf sea from glider observations

10.5194/bg-2016-118 ◽

2016 ◽

Author(s):

Lucas Merckelbach

Keyword(s):

Real Time ◽

North Sea ◽

Current Data ◽

Pass Filter ◽

Low Pass Filter ◽

Real Time Mode ◽

The North ◽

Shelf Sea ◽

The North Sea ◽

Better Than

Abstract. Ocean gliders have become ubiquitous observation platforms in the ocean in recent years. They are also increasingly used in coastal environments. The coastal observatory system COSYNA has pioneered the use of gliders in the North Sea, a shallow tidally energetic shelf sea. For operational reasons, the gliders operated in the North Sea are programmed to resurface every 3–5 hours. The glider's deadreckoning algorithm yields depth averaged currents, averaged in time over each subsurface interval. Under operational conditions these averaged currents are a poor approximation of the instantaneous tidal current. In this work an algorithm is developed that estimates the instantaneous current (tidal and residual) from glider observations only. The algorithm uses a second-order Butterworth low-pass filter to estimate the residual current component, and a Kalman filter based on the linear shallow water equations for the tidal component. A comparison of data from a glider experiment with current data from an ADCP deployed nearby shows that the standard deviations for the east and north current components are better than 7 cm s−1 in near-real time mode, and improve to better than 5 cm s−1 in delayed mode, where the filters can be run forward and backward. In the near-real time mode the algorithm provides estimates of the currents that the glider is expected to encounter during its next few dives. Combined with a behavioural and dynamic model of the glider, this yields predicted trajectories, the information of which is incorporated in warning messages issued to ships by the (German) authorities. In delayed mode the algorithm produces useful estimates of the depth averaged currents, which can be used in (process-based) analyses in case no other source of measured current information is available.

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Image Completion Using Randomized Correspondence

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.271-273.229 ◽

2011 ◽

Vol 271-273 ◽

pp. 229-234

Author(s):

Yun Ling ◽

Hai Tao Sun ◽

Jian Wei Han ◽

Xun Wang

Keyword(s):

Real Time ◽

Random Sampling ◽

Nearest Neighbor ◽

Structural Constraint ◽

Image Completion ◽

Image Patches ◽

Real Time Applications ◽

Surrounding Areas ◽

Straight Lines ◽

Better Than

Image completion techniques can be used to repair unknown image regions. However, existing techniques are too slow for real-time applications. In this paper, an image completion technique based on randomized correspondence is presented to accelerate the completing process. Some good patch matches are found via random sampling and propagated to surrounding areas. Approximate nearest neighbor matches between image patches can be found in real-time. For images with strong structure, straight lines or curves across unknown regions can be manually specified to preserve the important structures. In such case, search is only performed on specified lines or curves. Finally, the remaining unknown regions can be filled using randomized correspondence with structural constraint. The experiments show that the quality and speed of presented technique are much better than that of existing methods.

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Depth-averaged instantaneous currents in a tidally dominated shelf sea from glider observations

Biogeosciences ◽

10.5194/bg-13-6637-2016 ◽

2016 ◽

Vol 13 (24) ◽

pp. 6637-6649 ◽

Cited By ~ 1

Author(s):

Lucas Merckelbach

Keyword(s):

Real Time ◽

North Sea ◽

Current Data ◽

Pass Filter ◽

Low Pass Filter ◽

Real Time Mode ◽

The North ◽

Shelf Sea ◽

The North Sea ◽

Better Than

Abstract. Ocean gliders have become ubiquitous observation platforms in the ocean in recent years. They are also increasingly used in coastal environments. The coastal observatory system COSYNA has pioneered the use of gliders in the North Sea, a shallow tidally energetic shelf sea. For operational reasons, the gliders operated in the North Sea are programmed to resurface every 3–5 h. The glider's dead-reckoning algorithm yields depth-averaged currents, averaged in time over each subsurface interval. Under operational conditions these averaged currents are a poor approximation of the instantaneous tidal current. In this work an algorithm is developed that estimates the instantaneous current (tidal and residual) from glider observations only. The algorithm uses a first-order Butterworth low pass filter to estimate the residual current component, and a Kalman filter based on the linear shallow water equations for the tidal component. A comparison of data from a glider experiment with current data from an acoustic Doppler current profilers deployed nearby shows that the standard deviations for the east and north current components are better than 7 cm s−1 in near-real-time mode and improve to better than 6 cm s−1 in delayed mode, where the filters can be run forward and backward. In the near-real-time mode the algorithm provides estimates of the currents that the glider is expected to encounter during its next few dives. Combined with a behavioural and dynamic model of the glider, this yields predicted trajectories, the information of which is incorporated in warning messages issued to ships by the (German) authorities. In delayed mode the algorithm produces useful estimates of the depth-averaged currents, which can be used in (process-based) analyses in case no other source of measured current information is available.

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The Range Values for the Design Parameters of Nanoengineered Concrete Components. Characteristics, Properties, Amounts and Effects on the Concrete Behaviour

Advanced Engineering Forum ◽

10.4028/www.scientific.net/aef.8-9.277 ◽

2013 ◽

Vol 8-9 ◽

pp. 277-284

Author(s):

Olar Radu ◽

Traian Onet

Keyword(s):

Compressive Strength ◽

Structural Material ◽

Real Time ◽

New Products ◽

Structural Behavior ◽

Design Parameters ◽

Quality Requirements ◽

Research Goal ◽

Better Than

The nanometric scale researches results can be found, in present, in every industry domains, due to the effects of the new products, obtained on the basis of this researches. In the concrete industry, the research goal at this level is to obtain, finally, a material with new features, whose structural behavior to be considerably better than of the current one. Basically, it aims to achieve, using nanotechnologies, a new structural material for constructions, starting from the current concrete advantages (good compressive strength, durability, etc.), eliminating the disadvantages (low tensile resistance, cracks, etc.), and controlling, in the same time, the costs. Thus, in this paper are presented the required parameters in order to obtain this kind of material, by highlighting the nanocomponents characteristics and the quantities that are used to achieve the expected quality requirements. The real time influence of these nanocomponents on the quality of the studied material can be observed using a dedicated software, specially developed for this purpose.

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Thermal Decomposition of Energetic Materials 26. Simultaneous Temperature Measurements of the Condensed Phase and Rapid-Scan FT-IR Spectroscopy of the Gas Phase at High Heating Rates

Applied Spectroscopy ◽

10.1366/0003702874447626 ◽

1987 ◽

Vol 41 (7) ◽

pp. 1147-1151 ◽

Cited By ~ 36

Author(s):

J. T. Cronin ◽

T. B. Brill

Keyword(s):

Real Time ◽

Condensed Phase ◽

Energetic Materials ◽

Buffer Gas ◽

Heating Rates ◽

Decomposition Products ◽

Gaseous Products ◽

Rapid Scan ◽

Ft Ir ◽

Better Than

Rapid-scan infrared spectroscopy (RSFT-IR) with better than 100-ms temporal resolution has been used to quantify the gas decomposition products of energetic materials in real time at various heating rates up to 800°C/s and under buffer gas pressures of 1 to 1000 psi. A new method is described that permits simultaneous real-time recording of the temperature of the condensed phase and of the IR spectra of the gaseous products under the above conditions. Endothermic and exothermic events in the condensed phase can now be correlated with the evolved gases under conditions approaching those of combustion. The design and procedure for using the cell are given and are applied to the thermolysis of 1,7-diazido-2,4,6-trinitro-2,4,6-triazaheptane (DATH) and pentaery-thrityltetrammonium nitrate (PTTN).

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