scholarly journals Spectral analysis of Floating Car Data

2003 ◽  
Vol 1 ◽  
pp. 139-142 ◽  
Author(s):  
F. Gössel ◽  
E. Michler ◽  
B. Wrase
Keyword(s):  
Spectral Characteristics ◽  
Measurement Data ◽  
Essential Property ◽  
Time Profiles ◽  
Floating Car Data ◽  
Starting Point ◽  
Vehicle Velocity ◽  
Low Pass ◽  
Traffic Scenario ◽  
Sample Rate

Abstract. Floating Car Data (FCD) are one important data source in traffic telematic systems. The original variable in these systems is the vehicle velocity. The paper analyses the measured value “vehicle velocity" by methods of information technology. Consequences for processing, transmission and storage of FCD under condition of limited resources are discussed. Starting point of the investigation is the analysis of spectral characteristics of velocity-time-profiles. The spectra are determined by the Discrete Fourier Transform (DFT) from measurement data and simulation data of a microscopic traffic model. One essential property of velocity-time-profiles is their low-pass characteristic. The resulting cut-off-frequency is comparatively small and depends on the traffic scenario. Conclusions concerning the necessary sample rate in FCD systems and the processing of raw data are discussed. Finally the transinformation of velocity-time-profiles is analysed. This results in similar values for an optimal sample rate of FCD systems under condition of limited transmission capacity.

Entropie analysis of floating car data systems

2005 ◽  
Vol 2 ◽  
pp. 169-174
Author(s):  
F. Gössel ◽  
E. Michler ◽  
B. Wrase
Keyword(s):  
Field Trials ◽  
Vehicle Speed ◽  
Data Systems ◽  
Traffic Condition ◽  
Time Profiles ◽  
Spatial Segmentation ◽  
Floating Car Data ◽  
Original Variable ◽  
Vehicle Velocity ◽  
Basic Prerequisite

Abstract. The knowledge of the actual traffic state is a basic prerequisite of modern traffic telematic systems. Floating Car Data (FCD) systems are becoming more and more important for the provision of actual and reliable traffic data. In these systems the vehicle velocity is the original variable for the evaluation of the current traffic condition. As real FCDsystems are operating under conditions of limited transmission and processing capacity the analysis of the original variable vehicle speed is of special interest. Entropy considerations are especially useful for the deduction of fundamental restrictions and limitations. The paper analyses velocity-time profiles by means of information entropy. It emphasises in quantification of the information content of velocity-time profiles and the discussion of entropy dynamic in velocity-time profiles. Investigations are based on empirical data derived during field trials. The analysis of entropy dynamic is carried out in two different ways. On one hand velocity differences within a certain interval of time are used, on the other hand the transinformation between velocities in certain time distances was evaluated. One important result is an optimal sample-rate for the detection of velocity data in FCD-systems. The influence of spatial segmentation and of different states of traffic was discussed.

scholarly journals Pasang Surut, Arus dan Gelombang Berdasarkan Data Pengukuran Acoustic Doppler Current Profiler di Perairan Pulau Cilik, Karimunjawa

2020 ◽  
Vol 9 (1) ◽  
pp. 37-44
Author(s):  
Elis Indrayanti ◽  
Diah Permata Wijayanti ◽  
Hendry Syahputra Ropinus Siagian
Keyword(s):  
Coral Cover ◽  
Measurement Data ◽  
Acoustic Doppler Current Profiler ◽  
Ocean Currents ◽  
Time Interval ◽  
Live Coral ◽  
Actual Measurement ◽  
M 10 ◽  
Current Profiler ◽  
Sample Rate

Pulau Cilik merupakan gugusan pulau di Karimunjawa yang menjadi salah satu destinasi wisata bahari di Indonesia. Perairan ini kaya akan terumbu karang dan ikan berwarna-warni dengan  tutupan karang hidup yang masih tinggi. Proses hidrodinamika seperti pasang surut, arus laut dan gelombang laut secara langsung maupun tidak langsung berpengaruh terhadap kondisi terumbu karang, oleh karena itu penelitian ini perlu dilakukan. Tujuan penelitian adalah untuk mengetahui karakteristik pasang surut, arus laut dan gelombang berdasarkan data pengukuran Acoustic Doppler Current Profiler (ADCP) di Perairan Pulau Cilik, Karimunjawa. Pengukuran dilaksanakan selama 7x24 jam dengan interval waktu 600 dt dan sample rate 300 dt. Posisi ADCP pada -5.8177°S  dan 110.5096°E. Kedalaman total pengukuran 14 m dengan kedalaman aktif pengukuran 12 m, yang terbagi menjadi 6 lapisan kedalaman yaitu 2 m, 4 m, 6 m, 8 m, 10 m, dan 12 m.  Hasil pengukuran menunjukkan bahwa Perairan Pulau Cilik, Karimunjawa memiliki tipe pasang surut campuran condong harian tunggal dengan nilai formzahl sebesar 2.55. Kecepatan arus bervariasi dengan rata-rata pada seluruh lapisan antara 5.57–6.35 cm/dt, sedangkan arahnya bi-directional yaitu memiliki dua muka arah (timur dan barat-barat daya). Tinggi dan periode gelombang yang didapatkan pada saat pengamatan relatif kecil. Cilik Island Waters in Karimunjawa is one of the marine tourism destinations in Indonesia. These waters are rich in coral reefs and colorful fish with high live coral cover. Hydrodynamic processes as tides, ocean currents, and waves influence the performance of coral reef through direct or indirect effects. Therefore this research needs to be done. The purpose of this study was to determine the characteristics of tides, ocean currents, and waves based on Acoustic Doppler Current Profiler (ADCP) measurement data in Cilik Island Waters, Karimunjawa. Measurements were carried out for 7 x 24 hours (2 April 2017 - 9 April 2017) with a time interval of 600 s and a sample rate of 300 s. The ADCP position is -5.8177 ° S and 110.5096 ° E. The total depth is 14 m with an actual measurement depth of 12 m, which is divided into 6 layers of depth namely 2 m, 4 m, 6 m, 8 m, 10 m, and 12 m. Result shown that  Cilik Island, Karimunjawa, have a single mixed daily tidal type with a formzahl value of 2.55. Current velocity varies with the average in all layers between 5.57-6.35 cm/s, while the direction is bi-directional, which has two faces (east and west-southwest). The height and wave period obtained at the time of observation are relatively small. 

Analysis on Adjusting Effect and Spectral Characteristics of Digital Image Sampling

2014 ◽  
Vol 539 ◽  
pp. 471-474
Author(s):  
Hai Ying Liu
Keyword(s):  
Digital Image ◽  
Hot Spot ◽  
Modern Art ◽  
Spectral Characteristics ◽  
Image Process ◽  
Pass Filter ◽  
Low Pass Filter ◽  
Image Sampling ◽  
Low Pass ◽  
Continuous Tone

When it comes to the digitized image, it is a process of converting analog image of continuous tone which has been sampled and quantized into digital image. The application of digital technology in modern art has become one of the hot spot in this field. First of all, this paper undertakes the digital image process of image. According to the filtering properties of the Dirac function, this paper analyzes the two-dimensional sampling principle of digital image. Based on this, the relationship between image spectrum before sampling and after sampling is compared and analyzed according to the related properties of Fourier transform. And then it is obtained that it is concluded that the ideal low-pass filter can make the sample undistorted. By further analyzing the error of the sampling value quantification processing, the rebuilt best quantitative values of image can be obtained. Thats to say, the reconstruction of digital image is the inverse process of image sampling. To a certain extent, it provides scientific theoretical basis for the integration of digital image in modern art design.

scholarly journals System of Laser Monitoring of Water Pollution with Application of Relative Description of Signal Shape

2020 ◽  
Vol 11 (2) ◽  
pp. 114-121
Author(s):  
V. A. Alekseev ◽  
S. I. Yuran ◽  
V. P. Usoltsev ◽  
D. N. Shulmin
Keyword(s):  
Water Pollution ◽  
Spectral Characteristics ◽  
Measurement Data ◽  
Rational Approach ◽  
Relationship Matrix ◽  
Design Basis ◽  
Separate Branch ◽  
Lattice Function ◽  
Design Basis Accident ◽  
Laser Monitoring

As a rule, the wastewater treatment system is not designed to filter substances formed, as a result of beyond design basis accident. The nature of the beyond design basis accident is associated with the shortterm appearance of a clot of these substances in wastewater, determined by the volume of the substance storage tank. Therefore, a rational approach is to divert this portion of the formed substances into a separate branch of the sewage system or sedimentation tanks. The aim of the work is to implement this approach by creating a laser monitoring system for water pollution.The article proposes a system for automatic detection of a clot of emergency discharge of pollutants into the wastewater of an industrial enterprise. The structural diagram of the system and the purpose of its main elements are given. The system should provide clot detection in real time. To ensure this function, a preliminary study is made of the spectral characteristics of all substances that may appear in wastewater in the event of an emergency.Based on these data, the wavelengths of laser radiation in the system are selected. The obtained measurement data from several probes are presented in the form of a lattice function, which is translated into a relative description representing the order relationship matrix on the set of lattice function components. The relative description is invariant to linear changes in the lattice function. The decision to detect any substance from emergency discharges is made based on a comparison of the relative description of the measurements with the standards prepared at the stage of system setup.The article provides an example of the formation of standards for emergency clots from glycerin and allyl alcohol. The graphs of the lattice functions obtained from the IR spectra of emergency discharges of these substances are given; algorithms for constructing a lattice function and comparison of lattice functions. Thus, using the developed mathematical description of the shape of digital signals based on the relative description, the signal of the monitoring curve can be described in the form of a curve of the optical density change of an aqueous medium.

scholarly journals Numerical methodology for evaluation the combustion and emissions characteristics on WLTP in the light duty dual-fuel diesel vehicle

2021 ◽  
Author(s):  
Zbigniew Kneba ◽  
Denys Stepanenko ◽  
Jacek Rudnicki
Keyword(s):  
Internal Combustion Engines ◽  
Test Procedure ◽  
Real Life ◽  
Dual Fuel ◽  
Velocity Versus ◽  
Engine Operation ◽  
Time Profiles ◽  
General Terms ◽  
Vehicle Velocity ◽  
Harmful Emissions

The worldwide aim of reducing environmental impact from internal combustion engines bring more and more stringent emission regulations. In 2017 by EU has been adopted new harmonized test procedure called WLTP. In general terms this test was designed for determining the levels of harmful emissions and fuel consumption of traditional and hybrid cars. This procedure contains specific driving scenarios which representing real-life driving patterns. Test cycles contain vehicle velocity versus time profiles and directly in powertrain analysis on the test benches cannot be used. In order to back calculate drive cycles to engine rpm versus torque profiles a simple longitudinal vehicle dynamics method was used in this paper. Moreover, in order to determine most representative engine operation points duing WLTP a density based grid clustering method was implemented. The experimental part of the study focuses on the comparative evaluation of the effect of various diesel to LPG substitution ratios (0% LPG, 10% LPG, 20% LPG and 30% LPG) on combustion and emission characteristics of dual-fuel diesel engine.

scholarly journals Turbulence in a coastal environment: the case of Vindeby

2021 ◽  
Author(s):  
Rieska Mawarni Putri ◽  
Etienne Cheynet ◽  
Charlotte Obhrai ◽  
Jasna Bogunovic Jakobsen
Keyword(s):  
Wind Turbines ◽  
Wind Farm ◽  
Similarity Theory ◽  
Spectral Characteristics ◽  
Measurement Data ◽  
Offshore Wind ◽  
Wind Component ◽  
Neutral Atmosphere ◽  
Strong Wind ◽  
Offshore Wind Turbines

Abstract. Turbulence spectral characteristics for various atmospheric stratifications are studied using the observations from an offshore mast at Vindeby wind farm. Measurement data at 6 m, 18 m and 45 m above the mean sea level are considered. At the lowest height, the normalized power spectral densities of the velocity components show deviations from Monin-Obukhov similarity theory (MOST). A significant co-coherence at the wave spectral peak frequency between the vertical velocity component and the velocity of the sea surface is observed, but only when the significant wave heights exceed 0.9 m. The turbulence spectra at 18 m generally follow MOST and are consistent with the empirical spectra established on the FINO1 offshore platform from an earlier study. The data at 45 m is associated with a high-frequency measurement noise which limits its analysis to strong wind conditions only. The estimated co-coherence of the along-wind component under near-neutral atmosphere matches remarkably well with those at FINO1. The turbulence characteristics estimated from the present dataset are valuable to better understand the structure of turbulence in the marine atmospheric boundary layer and are relevant for load estimations of offshore wind turbines. Yet, a direct application of the results to other offshore or coastal sites should be exercised with caution, since the dataset is collected in shallow waters and at heights lower than the hub height of the current and the future state-of-the-art offshore wind turbines.

scholarly journals Influence of a Light Source Installed in a Luminaire of Opal Sphere Type on the Effect of Light Pollution

Energies ◽  
2020 ◽  
Vol 13 (2) ◽  
pp. 306 ◽  
Author(s):  
Przemyslaw Tabaka ◽  
Pawel Rozga
Keyword(s):  
Light Source ◽  
Spectral Distribution ◽  
Spectral Characteristics ◽  
Measurement Data ◽  
Luminous Flux ◽  
Light Pollution ◽  
Light Sources ◽  
Pollution Effect ◽  
The Impact ◽  
Effect Of Light

The article presents the results of the studies concerning the influence of a light source installed in luminaire of opal sphere type on the light pollution effect of the night sky. It is known from literature reports that the effect of light pollution is influenced by the spectral distribution of light. Although the influence of the spectral distribution has been widely studied from different perspectives, there is still a need to study this phenomenon—for example, from the point of view of the spectral reflection properties of the ground, on which the lanterns are installed. Hence, the above-mentioned aspect was considered in the authors’ investigations. The luminaire considered has been equipped with 20 different light sources, including the latest generation of lamps (light-emitting diodes, LEDs) as well as the conventional ones. With respect to these light sources, the measurements of light distribution and spectral distribution of emitted radiation of the luminaire were performed. Having these measurement data, the simulations were carried out using the DIALux software, and the calculations were made using the specially prepared calculation tool. On the basis of the results obtained in this way this was stated that the type of light source installed in the luminaire has a significant effect on the sky glow. An important factor affecting light pollution is not only the value of the luminous flux emitted upward but also the spectral characteristics of the emitted radiation, the impact of which is most noticeable. The conclusions from the studies indicate the next steps in the analysis of the light pollution effect. These steps will be focused on extended analysis of LEDs as modern and developed light sources.

scholarly journals Optimization of relativistic laser–ion acceleration

2014 ◽  
Vol 2 ◽  
Author(s):  
J. Schreiber ◽  
F. Bell ◽  
Z. Najmudin
Keyword(s):  
Radiation Pressure ◽  
Pulse Energy ◽  
Laser System ◽  
Target Thickness ◽  
Ion Acceleration ◽  
Essential Property ◽  
Ion Energy ◽  
Starting Point ◽  
Ion Energies ◽  
Acceleration Model

Abstract Experiments have shown that the ion energy obtained by laser–ion acceleration can be optimized by choosing either the appropriate pulse duration or the appropriate target thickness. We demonstrate that this behavior can be described either by the target normal sheath acceleration model of Schreiber et al. or by the radiation pressure acceleration model of Bulanov and coworkers. The starting point of our considerations is that the essential property of a laser system for ion acceleration is its pulse energy and not its intensity. Maybe surprisingly we show that higher ion energies can be reached with reduced intensities.

Adaptive surface geometry determination in multi-material x-ray computed tomography using fringe projection

2021 ◽  
Author(s):  
Jonas Großeheide ◽  
Kilian Geiger ◽  
Ânderson Schmidt ◽  
Calvin Bütow ◽  
Benjamin Montavon ◽  
...  
Keyword(s):  
Measurement Data ◽  
Internal Surface ◽  
Detection Algorithm ◽  
Fringe Projection ◽  
X Rays ◽  
Surface Geometry ◽  
Data Set ◽  
X Ray ◽  
Starting Point ◽  
X Ray Computed

Abstract One of the main challenges during digital post-processing of x-ray computed tomographic (XCT) measurement data is the reconstruction of the surface geometry of the measured objects. Conventionally, the surface geometry is defined as an isosurface of identical greyscale values, i.e. the x-ray absorbance of the material, based on a linear interpolation between neighboring voxels. Due to the complex surface geometry and rough surface, XCT measurements of additively manufactured (AM) parts are particularly prone to measurement artefacts caused by various physical effects when the x-rays penetrate the material. The irregular greyscale values at the measured surface geometry render commonly used single threshold greyscale value based isosurfaces as insufficient for representing the external and internal surface of the measured objects. This issue becomes particularly apparent when measuring multi-material objects, such as additively manufactured objects with integrated RFID tags. To address this challenge, this study presents a methodology for reliable surface geometry determination of XCT data based on previously acquired fringe projection (FP) data. For this purpose, the conventionally acquired surfaces geometries from the XCT and FP measurements are extracted, pre-processed and registered to each other before being merged into a single mesh. This merged data set is subsequently used as a starting point or reference for a locally adaptive threshold surface detection algorithm, which is able to capture the surface geometry at a sub-voxel resolution. In order to validate the methodology and confirm the envisaged benefits, selected geometry elements of the resulting surface geometry from measurements samples manufactured by additive manufacturing with integrated RIFD tags are compared to coordinate measurement machine (CMM) reference measurements. The results indicate a more robust surface geometry detection against artifacts especially for multi-material applications.

scholarly journals Navigation Algorithm Applied to the Bit of Underwater Horizontal Directional Drilling in a Vibration Environment

2019 ◽  
Vol 36 (2) ◽  
pp. 249-256
Author(s):  
Ke Yang
Keyword(s):  
Angular Velocity ◽  
Spectral Characteristics ◽  
Sensor Data ◽  
Directional Drilling ◽  
Horizontal Directional Drilling ◽  
Pass Filter ◽  
Low Pass Filter ◽  
Navigation Algorithm ◽  
Low Pass ◽  
Kalman Filter Algorithm

Abstract In its working state, the bit used in underwater horizontal directional drilling (UHDD) produces a high-frequency vibration that can affect accuracy of navigation. We designed a low-pass filter with linear phase on the basis of spectral characteristics of sensor data. To improve further the accuracy of navigation, we deduce the state error model on the basis of the random walk model of acceleration and angular velocity. We use an indirect Kalman filter algorithm to correct the attitude and position of the bit used with UHDD on the basis of observations coming from our working state analysis. Last, we derive a complete navigation algorithm function, including the acquisition method of steady-state component of acceleration and angular velocity. Experimental results show that the navigation algorithm proposed in this paper can obtain accurate attitude and location information of the bit in a vibration environment.

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