peak points
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2021 ◽  
Vol 2021 ◽  
pp. 1-19
Author(s):  
Rui Tao ◽  
Jian Liu ◽  
Yuqing Song ◽  
Rui Peng ◽  
Dali Zhang ◽  
...  

Traffic peak is an important parameter of modern transport systems. It can be used to calculate the indices of road congestion, which has become a common problem worldwide. With accurate information about traffic peaks, transportation administrators can make better decisions to optimize the traffic networks and therefore enhance the performance of transportation systems. We present a traffic peak detection method, which constructs the Voronoi diagram of the input traffic flow data and computes the prominence of candidate peak points using the diagram. Salient peaks are selected based on the prominence. The algorithm takes O(n log n) time and linear space, where n is the size of the input time series. As compared with the existing algorithms, our approach works directly on noisy data and detects salient peaks without a smoothing prestep and thus avoids the dilemma in choosing an appropriate smoothing scale and prevents the occurrence of removing/degrading real peaks during smoothing step. The prominence of candidate peaks offers the subsequent analysis the flexibility to choose peaks at any scale. Experiments illustrated that the proposed method outperforms the existing smoothing-based methods in sensitivity, positive predictivity, and accuracy.


Author(s):  
Volodymyr Kripak ◽  
Vira Koliakova

At the design stage is very important for the formation of the reliability of any building is the stage of formation of the design model of the building, which is the basis for the construction of its load-bearing elements. The main at this stage is the adequacy of the adopted calculation model to the actual design scheme. A very important condition for assessing the actual operation of the building is to take into account the joint work of the upper part of the building (frame) with the foundations and soil base. The article examines some problems in the operation of structures, which are related to the choice of design models used in their design, on the example of a 9-storey parking lot built in the early 2000s on Pobeda Square in Kyiv. Chi-rural studies using PC LIRA-CAD analyzed the impact of joint work of the framework and foundations on the efforts at their contact. It was found that: - the impact of joint work of the frame and foundations is significant and is manifested only within a few lower floors of the frame; - taking into account the nonlinear operation of reinforced concrete structures in most cases significantly reduces the calculated forces at peak points - concentrators; - in the design process it is necessary to consider and analyze the variant design solutions of the system.


Symmetry ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1997
Author(s):  
Hai Zhang ◽  
Chenyu Zhang ◽  
Fengtao Lin ◽  
Xiugang Wang ◽  
Gengzhe Fu

Once a train breaks down on a busy railway line, it will affect the whole traffic network. However, when a rescue locomotive is hooked up to the broken train for towing it to the next station, it is common that coupling dislocation occurs, which results in damages to couplers and the driver’s cab. To ensure the safety of the trains during the coupling, it becomes crucial to determine whether they can be linked safely and automatically under different line conditions. In this paper, position and pose of the rescue locomotive and the broken train on the line are calculated by geometric analytical calculation method, which determines the position relation of their couplers. Then a so-called “coupling characteristic triangle” was proposed to determine whether trains can be safely and automatically linked on the railway line. The triangles are constructed by the peak points of the couplers head of the front vehicle and the rear one and border lines of secure coupling area on the couplers. By judging the shape of the triangle, it can directly judge whether their couplers can be connected successfully. The method has been applied to check the safety of the trains during coupling on the Nanchang urban railway Line 4. The results show that the maximum swing angle of the coupler reaches 17.3957° in the straight–curve section with a radius of 325 m. At this time, coupling is most difficult, and trains need to be connected manually through the tractor; all the calculation results are verified in the actual line. By comparing different calculation methods for judging coupling safety, it is shown that the method proposed in this paper is accurate, efficient, and users can judge coupling safety more intuitively.


2021 ◽  
Vol 13 (9) ◽  
pp. 4688
Author(s):  
Khurram Shehzad ◽  
Umer Zaman ◽  
Xiaoxing Liu ◽  
Jarosław Górecki ◽  
Carlo Pugnetti

COVID-19 has significantly affected the financial and commodity markets. The purpose of this investigation is to understand the impact of the COVID-19 crisis on Dow Jones and West Texas Intermediate (WTI) oil returns in relation to other crises using the Exponential Generalized Autoregressive Conditional Heteroskedasticity (EGARCH) model. The results indicate that COVID-19 and the accompanying lockdown have adversely impacted both yields and that the impact on oil prices is more significant than on the Dow Jones index. The variance and squared residuals of oil prices and the Dow Jones reached their highest historical levels during the COVID-19 outbreak, even higher than during the global financial crisis, and especially the VaR of both markets reached their historical peak points during the COVID-19 era. The variance of WTI during COVID-19 is higher than that of DJI, as was also the case during the financial crisis. These findings confirm that COVID-19 has negatively impacted investors’ ability to determine optimal portfolios and thus the sustainability of financial and energy markets more than the global financial crisis of 2007–2009. We, therefore, suggest that policy changes are needed to maintain financial sustainability and help investors deal with future financial and other crises.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
H. Busra Cagirici ◽  
Hikmet Budak ◽  
Taner Z. Sen

AbstractG-quadruplexes (G4s) are four-stranded nucleic acid structures with closely spaced guanine bases forming square planar G-quartets. Aberrant formation of G4 structures has been associated with genomic instability. However, most plant species are lacking comprehensive studies of G4 motifs. In this study, genome-wide identification of G4 motifs in barley was performed, followed by a comparison of genomic distribution and molecular functions to other monocot species, such as wheat, maize, and rice. Similar to the reports on human and some plants like wheat, G4 motifs peaked around the 5′ untranslated region (5′ UTR), the first coding domain sequence, and the first intron start sites on antisense strands. Our comparative analyses in human, Arabidopsis, maize, rice, and sorghum demonstrated that the peak points could be erroneously merged into a single peak when large window sizes are used. We also showed that the G4 distributions around genic regions are relatively similar in the species studied, except in the case of Arabidopsis. G4 containing genes in monocots showed conserved molecular functions for transcription initiation and hydrolase activity. Additionally, we provided examples of imperfect G4 motifs.


2021 ◽  
Vol 11 (3) ◽  
pp. 1032
Author(s):  
Dongbing Guo ◽  
Chunhui Wang ◽  
Baoling Qi

A novel differential method based on linear fitting is proposed to improve the accuracy of the pulse-ranging system. In this method, the Peak Points (PPs) of the traditional echo signal transformed into the Positive-Going Zero-Crossing Points (PGZCPs) of the differential echo signal. Then, we obtained the true zero-crossing point by the linear fitting of points near PGZCPs. We compared the differential method based on linear fitting (DMLF) and peak method. The Root Mean Square Error (RMSE) found with our method (0.1661 ns) is nearly a 50% reduction compared to that of the peak method (0.3318 ns), and a large number of experiments have demonstrated that the Relative Error (RE) of our proposed method is less than 30 ppm.


2020 ◽  
Author(s):  
Ondřej Mottl ◽  
John-Arvid Grytnes ◽  
Alistair W.R. Seddon ◽  
Manuel J. Steinbauer ◽  
Kuber P. Bhatta ◽  
...  

AbstractDynamics in the rate of compositional change beyond the time of human observation are uniquely preserved in palaeoecological sequences from peat or lake sediments. Changes in sedimentation rates and sampling strategies result in an uneven distribution of time intervals within stratigraphical data, which makes assessing rates of compositional change and the detection of periods with a high rate-of-change (RoC) or ‘peak-points’ challenging. Despite these known issues and their importance, and the frequent use of RoC in palaeoecology, there has been relatively little exploration of differing approaches to quantifying RoC.Here, we introduce R-Ratepol (an easy to use R package) that provides a robust numerical technique for detecting and summarising RoC patterns in complex multivariate time-ordered stratigraphical sequences. We compare the performance of common methods of estimating RoC using simulated pollen-stratigraphical data with known patterns of compositional change and temporal resolution. In addition, we apply our new methodology to four representative European pollen sequences.Simulated data show large differences in the successful detection of known patterns in RoC peak-point detection depending on the smoothing methods and dissimilarity coefficients used, and the level density and their taxonomic richness. Building on these results, we propose a new method of binning with a moving window in combination with a generalised additive model for peak-point detection. The method shows a 22% increase in the correct detection of peak-points and 4% lower occurrence of false positives compared to the more traditional way of peak selection by individual levels, as well as achieving a reasonable compromise between type I and type II errors. The four representative pollen sequences from Europe show that our methodological combination also performs well in detecting periods of significant compositional change including the onset of human activity, early land-use transformation, and changes in fire frequency.Expanding the approach using R-Ratepol to the increasingly available stratigraphical data on pollen, chironomids, or diatoms will allow future palaeoecological and macroecological studies to quantify, and then attribute, major changes in biotic composition across broad spatial areas through time.


The Novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused 414179 infected cases and 18440 deaths up to March 25, 2020. The aim of this study was to estimate the new cases of COVID-19 in future days in Iran based on multiple factors such as governmental actions and peoplechr('39')s behavior. We constructed the model based on governmental actions, peoplechr('39')s behavior and lag time for governmental action. We estimated the governmental actions ratio and people’s behavior with minimum sum square error with OptQuest arena software. By estimation the new cases under three scenarios for governmental actions, we predicted the new cases and cumulative death for different genders for all scenarios. Based on the first scenario, the maximum number of newly infected cases was 3117. Total cumulative death for 110th day for males and females respectively was 3157 and 2285. According to the second scenario, the maximum number of newly infected cases was 3117. Total cumulative death for 151st day for males and females respectively was 3504 and 2536. By selecting the third scenario, there were two peak points. In the first peak point, the maximum number of newly infected cases was 3117. In the second peak, the maximum number of newly infected cases was 3190. Based on the result of this study, it seems that the best option for the government is to keep social distance and close economic activity, so the number of new cases will be decreased.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Shengrong Xie ◽  
Yaohui Sun ◽  
En Wang ◽  
Dongdong Chen ◽  
Xiaoyu Wu ◽  
...  

Abstract To promote the engineering applications of high water backfill materials (HWBM) in mining, a series of experiments are performed to investigate the effects of the direct current (DC) electric field on the mechanic properties and electrical resistivity of HWBMs. Based on X-ray diffraction (XRD) and scanning electron microscopy (SEM) investigations, the influence of electrochemical treatment on the hydration products and the microstructure of the HWBM was studied. The results show that the peak strength, elastic modulus, deformation modulus and electrical resistivity of the HWBM samples all first increased and then decreased with the increasing of the potential gradient, and the peak points appeared when the potential gradient was 0.2 V/cm. The anisotropy of content of ettringite and calcium silicate hydrates (C–S–H) increased betweent the anodic and cathodic regions of samples. Meanwhile, microstructure in the anodic region of the samples was more stable after electrochemical treatment, which indicates that the different variation of mineralogical compositions and microstructures in different regions of the samples are the primary factors affecting the mechanic properties and electrical resistivity of the HWBM. Therefore, the electrochemical method is a potential technology to modify the engineering properties of the HWBM.


2020 ◽  
Vol 1010 ◽  
pp. 228-232
Author(s):  
Noruzaman Daud ◽  
Julie Juliewatty Mohamed ◽  
Mohamad Johari bin Abu ◽  
Mohd Fariz Ab Rahman ◽  
Siti Roshayu binti Hassan ◽  
...  

CCTO consist of huge dielectric constant up to 105 at temperature range -173 °C to 326 °C becomes an attraction to investigate the CCTO ceramics. The samples were tested using simultaneous thermogravimetry (TGA) and differential calorimetry (DSC) measurement in dual atmospheric gases condition by flowing nitrogen and oxygen gas. Phase changes of CCTO precursor were analyzed by X-ray diffraction machine. The samples CT900 and CT1000 occur both of mass loss and reabsorption due to the oxygen-rich environment. The mass loss for both samples CT900 and CT1000 has complete curves of CaCO3 decomposition. Sample CT900 shows incomplete of heat flow changes compare to samples CTNML and CT1000. The result shows that the formation of the CCTO phase structure does not depend on the oxygen gas environment but also requires specific heat of energy and temperature to changes the phase structure. DSC graph shows two magnitudes of heat flow changes for sample CT1000 that are an endothermic at temperature peak points 824 °C and 984 °C.


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