Search results for: dispersion compensation
935 Model of Cosserat Continuum Dispersion in a Half-Space with a Scatterer
Authors: Francisco Velez, Juan David Gomez
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Dispersion effects on the Scattering for a semicircular canyon in a micropolar continuum are analyzed, by using a computational finite element scheme. The presence of microrotational waves and the dispersive SV waves affects the propagation of elastic waves. Here, a contrast with the classic model is presented, and the dependence with the micropolar parameters is studied.Keywords: scattering, semicircular canyon, wave dispersion, micropolar medium, FEM modeling
Procedia PDF Downloads 542934 Model Free Terminal Sliding Mode with Gravity Compensation: Application to an Exoskeleton-Upper Limb System
Authors: Sana Bembli, Nahla Khraief Haddad, Safya Belghith
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This paper deals with a robust model free terminal sliding mode with gravity compensation approach used to control an exoskeleton-upper limb system. The considered system is a 2-DoF robot in interaction with an upper limb used for rehabilitation. The aim of this paper is to control the flexion/extension movement of the shoulder and the elbow joints in presence of matched disturbances. In the first part, we present the exoskeleton-upper limb system modeling. Then, we controlled the considered system by the model free terminal sliding mode with gravity compensation. A stability study is realized. To prove the controller performance, a robustness analysis was needed. Simulation results are provided to confirm the robustness of the gravity compensation combined with to the Model free terminal sliding mode in presence of uncertainties.Keywords: exoskeleton- upper limb system, model free terminal sliding mode, gravity compensation, robustness analysis
Procedia PDF Downloads 144933 Price Compensation Mechanism with Unmet Demand for Public-Private Partnership Projects
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Public-private partnership (PPP), as an innovative way to provide infrastructures by the private sector, is being widely used throughout the world. Compared with the traditional mode, PPP emerges largely for merits of relieving public budget constraint and improving infrastructure supply efficiency by involving private funds. However, PPP projects are characterized by large scale, high investment, long payback period, and long concession period. These characteristics make PPP projects full of risks. One of the most important risks faced by the private sector is demand risk because many factors affect the real demand. If the real demand is far lower than the forecasting demand, the private sector will be got into big trouble because operating revenue is the main means for the private sector to recoup the investment and obtain profit. Therefore, it is important to study how the government compensates the private sector when the demand risk occurs in order to achieve Pareto-improvement. This research focuses on price compensation mechanism, an ex-post compensation mechanism, and analyzes, by mathematical modeling, the impact of price compensation mechanism on payoff of the private sector and consumer surplus for PPP toll road projects. This research first investigates whether or not price compensation mechanisms can obtain Pareto-improvement and, if so, then explores boundary conditions for this mechanism. The research results show that price compensation mechanism can realize Pareto-improvement under certain conditions. Especially, to make the price compensation mechanism accomplish Pareto-improvement, renegotiation costs of the government and the private sector should be lower than a certain threshold which is determined by marginal operating cost and distortionary cost of the tax. In addition, the compensation percentage should match with the price cut of the private investor when demand drops. This research aims to provide theoretical support for the government when determining compensation scope under the price compensation mechanism. Moreover, some policy implications can also be drawn from the analysis for better risk-sharing and sustainability of PPP projects.Keywords: infrastructure, price compensation mechanism, public-private partnership, renegotiation
Procedia PDF Downloads 179932 The Powerful of Training; Development and Compensation; Rewards in Sustaining SME’s Performance
Authors: Mohd Fitri Mansor, Noor Hidayah Abu, Hussen Nasir
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Human capital is one of valuable assets to the organization in order to sustain organization performance and to achieve both employees and employer objectives. The aim of the study is to examine the powerful of both Human Resource practices (i.e. Training & Development and Compensation & Rewards) towards sustaining SME’s performance. The objectives of the current study are to examine the relationship between training and development as well as compensation and rewards in sustaining Malaysian SME’s performance. Finally, is to identify the strongest variable contribute to the sustainability of SMEs performance. The result from 80 Malaysian SME’s owners found that both variables training & development and compensation & rewards significantly contributes to the sustainability of SME,s performance. Meanwhile, the strongest variable contributes to the sustainability of SMEs performance was training and development. The study contributes to the knowledge and awareness to the SME’s owners an important or the powerful of human resource practices in sustaining their organization performance.Keywords: training and development, compensation and rewards, sustainability, SME’s performance
Procedia PDF Downloads 480931 Pd Supported on Activated Carbon: Effect of Support Texture on the Dispersion of Pd
Authors: Ji Sun Kim, Jae Ho Baek, Kyeong Ho Kim, Ji Hae Ha, Seong Soo Hong, Jung-Wook Park, Man Sig Lee
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Carbon supported palladium catalysts have been used in many industrial reactions, especially for hydrogenation in the fine chemical industry. Porous carbons had been widely used as catalyst supports due to its higher surface area and larger pore volume. The specific surface area, pore structure and surface chemical functional groups of porous carbon affects metal dispersion and particle size. In this paper, we confirm the effect of support texture on the dispersion of Pd. Pd catalyst supported on activated carbon having various specific surface area were characterized by BET, XRD and FE-TEM. Catalyst activity and dispersion of prepared catalyst were evaluated on the basis of the CO adsorption capacity by CO-chemisorption. As concluding remark to this part of our study, let us note that specific area of carbon play important role on the synthesis of Pd/C catalyst/.Keywords: carbon, dispersion, Pd/C, specific are, support
Procedia PDF Downloads 351930 Evaluation of the Impact of Green Infrastructure on Dispersion and Deposition of Particulate Matter in Near-Roadway Areas
Authors: Deeksha Chauhan, Kamal Jain
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Pollutant concentration is high in near-road environments, and vegetation is an effective measure to mitigate urban air quality problems. This paper presents the influence of roadside green infrastructure in dispersion and Deposition of Particulate matter (PM) by the ENVI-met Simulations. Six green infrastructure configurations were specified (i) hedges only, (ii) trees only, (iii) a mix of trees and shrubs (iv) green barrier (v) green wall, and (vi) no tree buffer were placed on both sides of the road. The changes in concentrations at all six scenarios were estimated to identify the best barrier to reduce the dispersion and deposition of PM10 and PM2.5 in an urban environment.Keywords: barrier, concentration, dispersion, deposition, Particulate matter, pollutant
Procedia PDF Downloads 144929 Numerical Study of Blackness Factor Effect on Dark Solitons
Authors: Khelil Khadidja
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In this paper, blackness of dark solitons is considered. The exact combination between nonlinearity and dispersion is responsible of solitons stability. Dark solitons get born when dispersion is abnormal and balanced by nonlinearity, at the opposite of brillant solitons which is born by normal dispersion and nonlinearity together. Thanks to their stability, dark solitons are suitable for transmission by optical fibers. Dark solitons which are a solution of Nonlinear Schrodinger equation are simulated with Matlab to discuss the influence of coefficient of blackness. Results show that there is a direct proportion between the coefficient of blackness and the intensity of dark soliton. Those gray solitons are stable and convenient for transmission.Keywords: abnormal dispersion, nonlinearity, optical fiber, soliton
Procedia PDF Downloads 198928 Effects of Compensation on Distribution System Technical Losses
Authors: B. Kekezoglu, C. Kocatepe, O. Arikan, Y. Hacialiefendioglu, G. Ucar
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One of the significant problems of energy systems is to supply economic and efficient energy to consumers. Therefore studies has been continued to reduce technical losses in the network. In this paper, the technical losses analyzed for a portion of European side of Istanbul MV distribution network for different compensation scenarios by considering real system and load data and results are presented. Investigated system is modeled with CYME Power Engineering Software and optimal capacity placement has been proposed to minimize losses.Keywords: distribution system, optimal capacitor placement, reactive power compensation, technical losses
Procedia PDF Downloads 673927 Effect of Management Compensation and Auditor Reputation on Tax Management in the Listed Banking Companies in Indonesia
Authors: Fahreza, Yudhi Herliansyah, Harnovinsah
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This study aims to examine how management compensation and auditor reputation effect on corporate tax management in banking using a sample banking companies listed in Indonesia Stock Exchange. At first, this study examines how the influence of management compensation on the implementation of tax management that may be made by management in order to improve the performance of the company. Second, this study also examines the effect of auditor reputation conducting audit on the implementation of the tax management. The population used in this study is the banking companies listed in Indonesia Stock Exchange. The method used was purposive sampling because the samples of this study have certain criteria that are tailored to the purpose of the study. Based on purposive sampling method, the number of samples in this study is 28 samples. Hypothesis tested using multiple regression analysis. The results of this study indicate that on the 5 % significance level, management compensation significantly influenced tax management as measured using the proxy book tax gap. Other result is management compensation does not significantly affect the tax management that measured using a proxy GAAP effective tax rate. In addition the auditor's reputation does significantly influence tax management as measured using the proxy book tax gap and GAAP effective tax rate.Keywords: tax management, management compensation, auditor reputation, corporate characteristic
Procedia PDF Downloads 300926 Employee Inventor Compensation: A New Quest for Comparative Law
Authors: Andrea Borroni
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The evolution of technology, the global scale of economy, and the new short-term employment contracts make a very peculiar set of disposition of raising interest for the legal interpreter: the employee inventor compensation. Around the globe, this issue is differently regulated according to the legal systems; therefore, it is extremely fragmented. Of course, employers with transnational businesses should face this issue from a comparative perspective. Different legal regimes are available worldwide awarding, as a consequence, diverse compensation to the inventor and according to their own methodology. Given these premises, the recourse to comparative law methodology (legal formants, diachronic and synchronic methodology, common core approach) is the best equipped to face all these different national approaches in order to achieve a tidy systematic. This research, so, elaborates a map of the specific criteria to grant the compensation for the inventor and to show the criteria to calculate them. This finding has been the first step to find out a common core of the discipline given by the common features present in the different legal systems.Keywords: comparative law, employee invention, intellectual property, legal transplant
Procedia PDF Downloads 333925 Quantification of Dispersion Effects in Arterial Spin Labelling Perfusion MRI
Authors: Rutej R. Mehta, Michael A. Chappell
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Introduction: Arterial spin labelling (ASL) is an increasingly popular perfusion MRI technique, in which arterial blood water is magnetically labelled in the neck before flowing into the brain, providing a non-invasive measure of cerebral blood flow (CBF). The accuracy of ASL CBF measurements, however, is hampered by dispersion effects; the distortion of the ASL labelled bolus during its transit through the vasculature. In spite of this, the current recommended implementation of ASL – the white paper (Alsop et al., MRM, 73.1 (2015): 102-116) – does not account for dispersion, which leads to the introduction of errors in CBF. Given that the transport time from the labelling region to the tissue – the arterial transit time (ATT) – depends on the region of the brain and the condition of the patient, it is likely that these errors will also vary with the ATT. In this study, various dispersion models are assessed in comparison with the white paper (WP) formula for CBF quantification, enabling the errors introduced by the WP to be quantified. Additionally, this study examines the relationship between the errors associated with the WP and the ATT – and how this is influenced by dispersion. Methods: Data were simulated using the standard model for pseudo-continuous ASL, along with various dispersion models, and then quantified using the formula in the WP. The ATT was varied from 0.5s-1.3s, and the errors associated with noise artefacts were computed in order to define the concept of significant error. The instantaneous slope of the error was also computed as an indicator of the sensitivity of the error with fluctuations in ATT. Finally, a regression analysis was performed to obtain the mean error against ATT. Results: An error of 20.9% was found to be comparable to that introduced by typical measurement noise. The WP formula was shown to introduce errors exceeding 20.9% for ATTs beyond 1.25s even when dispersion effects were ignored. Using a Gaussian dispersion model, a mean error of 16% was introduced by using the WP, and a dispersion threshold of σ=0.6 was determined, beyond which the error was found to increase considerably with ATT. The mean error ranged from 44.5% to 73.5% when other physiologically plausible dispersion models were implemented, and the instantaneous slope varied from 35 to 75 as dispersion levels were varied. Conclusion: It has been shown that the WP quantification formula holds only within an ATT window of 0.5 to 1.25s, and that this window gets narrower as dispersion occurs. Provided that the dispersion levels fall below the threshold evaluated in this study, however, the WP can measure CBF with reasonable accuracy if dispersion is correctly modelled by the Gaussian model. However, substantial errors were observed with other common models for dispersion with dispersion levels similar to those that have been observed in literature.Keywords: arterial spin labelling, dispersion, MRI, perfusion
Procedia PDF Downloads 369924 New Result for Optical OFDM in Code Division Multiple Access Systems Using Direct Detection
Authors: Cherifi Abdelhamid
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In optical communication systems, OFDM has received increased attention as a means to overcome various limitations of optical transmission systems such as modal dispersion, relative intensity noise, chromatic dispersion, polarization mode dispersion and self-phase modulation. The multipath dispersion limits the maximum transmission data rates. In this paper we investigate OFDM system where multipath induced intersymbol interference (ISI) is reduced and we increase the number of users by combining OFDM system with OCDMA system using direct detection Incorporate OOC (orthogonal optical code) for minimize a bit error rate.Keywords: OFDM, OCDMA, OOC (orthogonal optical code), (ISI), prim codes (Pc)
Procedia PDF Downloads 651923 Design of Active Power Filters for Harmonics on Power System and Reducing Harmonic Currents
Authors: Düzgün Akmaz, Hüseyin Erişti
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In the last few years, harmonics have been occurred with the increasing use of nonlinear loads, and these harmonics have been an ever increasing problem for the line systems. This situation importantly affects the quality of power and gives large losses to the network. An efficient way to solve these problems is providing harmonic compensation through parallel active power filters. Many methods can be used in the control systems of the parallel active power filters which provide the compensation. These methods efficiently affect the performance of the active power filters. For this reason, the chosen control method is significant. In this study, Fourier analysis (FA) control method and synchronous reference frame (SRF) control method are discussed. These control methods are designed for both eliminate harmonics and perform reactive power compensation in MATLAB/Simulink pack program and are tested. The results have been compared for each two methods.Keywords: parallel active power filters, harmonic compensation, power quality, harmonics
Procedia PDF Downloads 457922 Low Nonlinear Effects Index-Guiding Nanostructured Photonic Crystal Fiber
Authors: S. Olyaee, M. Seifouri, A. Nikoosohbat, M. Shams Esfand Abadi
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Photonic Crystal Fibers (PCFs) can be used in optical communications as transmission lines. For this reason, the PCFs with low confinement loss, low chromatic dispersion, and low nonlinear effects are highly suitable transmission media. In this paper, we introduce a new design of index-guiding nanostructured photonic crystal fiber (IG-NPCF) with ultra-low chromatic dispersion, low nonlinearity effects, and low confinement loss. Relatively low dispersion is achieved in the wavelength range of 1200 to 1600nm using the proposed design. According to the new structure of nanostructured PCF presented in this study, the chromatic dispersion slope is -30(ps/km.nm) and the confinement loss reaches below 10-7 dB/km. While in the wavelength range mentioned above at the same time an effective area of more than 50.2μm2 is obtained.Keywords: optical communication systems, nanostructured, index-guiding, dispersion, confinement loss, photonic crystal fiber
Procedia PDF Downloads 559921 Experimental Investigation on the Effect of Ultrasonication on Dispersion and Mechanical Performance of Multi-Wall Carbon Nanotube-Cement Mortar Composites
Authors: S. Alrekabi, A. Cundy, A. Lampropoulos, I. Savina
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Due to their remarkable mechanical properties, multi-wall carbon nanotubes (MWCNTs) are considered by many researchers to be a highly promising filler and reinforcement agent for enhanced performance cementitious materials. Currently, however, achieving an effective dispersion of MWCNTs remains a major challenge in developing high performance nano-cementitious composites, since carbon nanotubes tend to form large agglomerates and bundles as a consequence of Van der Waals forces. In this study, effective dispersion of low concentrations of MWCNTs at 0.01%, 0.025%, and 0.05% by weight of cement in the composite was achieved by applying different sonication conditions in combination with the use of polycarboxylate ether as a surfactant. UV-Visible spectroscopy and Transmission electron microscopy (TEM) were used to assess the dispersion of MWCNTs in water, while the dispersion states of MWCNTs within the cement composites and their surface interactions were examined by scanning electron microscopy (SEM). A high sonication intensity applied over a short time period significantly enhanced the dispersion of MWCNTs at initial mixing stages, and 0.025% of MWCNTs wt. of cement, caused 86% and 27% improvement in tensile strength and compressive strength respectively, compared with a plain cement mortar.Keywords: dispersion, mechanical performance, multi wall carbon nanotubes, sonication conditions
Procedia PDF Downloads 320920 Numerical Simulation of the Air Pollutants Dispersion Emitted by CPH Using ANSYS CFX
Authors: Oliver Mărunţălu, Gheorghe Lăzăroiu, Elena Elisabeta Manea, Dana Andreya Bondrea, Lăcrămioara Diana Robescu
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This paper presents the results obtained by numerical simulation of the pollutants dispersion in the atmosphere coming from the evacuation of combustion gases resulting from the fuel combustion used by electric thermal power plant using the software ANSYS CFX-CFD. The model uses the Navier-Stokes equation to simulate the dispersion of pollutants in the atmosphere. We considered as important factors in elaboration of simulation the atmospheric conditions (pressure, temperature, wind speed, wind direction), the exhaust velocity of the combustion gases, chimney height and the obstacles (buildings). Using the air quality monitoring stations we have measured the concentrations of main pollutants (SO2, NOx and PM). The pollutants were monitored over a period of 3 months, after that we calculated the average concentration, which is used by the software. The concentrations are: 8.915 μg/m3 (NOx), 9.587 μg/m3 (SO2) and 42 μg/m3 (PM). A comparison of test data with simulation results demonstrated that CFX was able to describe the dispersion of the pollutant as well the concentration of this pollutants in the atmosphere.Keywords: air pollutants, computational fluid dynamics, dispersion, simulation
Procedia PDF Downloads 455919 Variable Shunt Reactors for Reactive Power Compensation of HV Subsea Cables
Authors: Saeed A. AlGhamdi, Nabil Habli, Vinoj Somasanran
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This paper presents an application of 230 kV Variable Shunt Reactors (VSR) used to compensate reactive power of dual 90 KM subsea cables. VSR integrates an on-load tap changer (OLTC) that adjusts reactive power compensation to maintain acceptable bus voltages under variable load profile and network configuration. An automatic voltage regulator (AVR) or a power management system (PMS) that allows VSR rating to be changed in discrete steps typically controls the OLTC. Typical regulation range start as minimum as 20% up to 100% and are available for systems up to 550kV. The regulation speed is normally in the order of seconds per step and approximately a minute from maximum to minimum rating. VSR can be bus or line connected depending on line/cable length and compensation requirements. The flexible reactive compensation ranges achieved by recent VSR technologies have enabled newer facilities design to deploy line connected VSR through either disconnect switches, which saves space and cost, or through circuit breakers. Lines with VSR are typically energized with lower taps (reduced reactive compensation) to minimize or remove the presence of delayed zero crossing.Keywords: power management, reactive power, subsea cables, variable shunt reactors
Procedia PDF Downloads 249918 The Applicability of Just Satisfaction in Inter-State Cases: A Case Study of Cyprus versus Turkey
Authors: Congrui Chen
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The European Court of Human Rights (hereinafter ECtHR) delivered its judgment of just satisfaction on the case of Cyprus v. Turkey, ordering a lump sum of 9,000,000 euros as the just compensation. It is the first time that the ECtHR applied the Article 41 of just compensation in an inter-state case, and it stands as the highest amount of just compensation awarded in the history of the ECtHR. The Cyprus v. Turkey case, which represents the most crucial contribution to European peace in the history of the court. This thesis uses the methodologies of textual research, comparison analysis, and case law study to go further on the following two questions specifically:(i) whether the just compensation is applicable in an inter-state case; (ii) whether such just compensation is of punitive nature. From the point of view of general international law, the essence of the case is the state's responsibility for the violation of individual rights. In other words, the state takes a similar diplomatic protection approach to seek relief. In the course of the development of international law today, especially with the development of international human rights law, States that have a duty to protect human rights should bear corresponding responsibilities for their violations of international human rights law. Under the specific system of the European Court of Human Rights, the just compensation for article 41 is one of the specific ways of assuming responsibility. At the regulatory level, the European Court of Human Rights makes it clear that the just satisfaction of article 41 of the Convention does not include punitive damages, as it relates to the issue of national sovereignty. Nevertheless, it is undeniable that the relief to the victim and the punishment to the responsible State are two closely integrated aspects of responsibility. In other words, compensatory compensation has inherent "punitive".Keywords: European Court of Human Right, inter-state cases, just satisfaction, punitive damages
Procedia PDF Downloads 270917 Simulations of High-Intensity, Thermionic Electron Guns for Electron Beam Thermal Processing Including Effects of Space Charge Compensation
Authors: O. Hinrichs, H. Franz, G. Reiter
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Electron guns have a key function in a series of thermal processes, like EB (electron beam) melting, evaporation or welding. These techniques need a high-intensity continuous electron beam that defocuses itself due to high space charge forces. A proper beam transport throughout the magnetic focusing system can be ensured by a space charge compensation via residual gas ions. The different pressure stages in the EB gun cause various degrees of compensation. A numerical model was installed to simulate realistic charge distributions within the beam by using CST-Particle Studio code. We will present current status of beam dynamic simulations. This contribution will focus on the creation of space charge ions and their influence on beam and gun components. Furthermore, the beam transport in the gun will be shown for different beam parameters. The electron source allows to produce beams with currents of 3 A to 15 A and energies of 40 keV to 45 keV.Keywords: beam dynamic simulation, space charge compensation, thermionic electron source, EB melting, EB thermal processing
Procedia PDF Downloads 334916 A Three Phase Shunt Active Power Filter for Currents Harmonics Elimination and Reactive Power Compensation
Authors: Amar Omeiri
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This paper presents a three-phase shunt active power filter for current harmonics suppression and reactive power compensation using the supply current as reference. The proposed APF has a simple control circuit; it consists of detecting the supply current instead of the load current. The advantages of this APF are simplicity of control circuits and low implementation cost. The simulation results show that the proposed APF can compensate the reactive power and suppress current harmonics with two types of non-linear loads.Keywords: active power filter, current harmonics and reactive power compensation, PWM inverter, Total Harmonic Distortion, power quality
Procedia PDF Downloads 587915 Investigation of Dispersion of Carbon Nanoparticles in Polymer Melt for the Fabrication of Functional Filaments
Authors: Merle Bischoff, Thomas Gries, Gunnar Seide
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Nanocomposites have become more and more important as the implementation of nanoparticles in polymer allows additional functions in common industrial parts. Especially in the fabrication of filaments or fibres nanomodification is important, as only very small fillers can be added to the very fine fibres (common diameter is 20 µm, fine filament are 1 µm). Discharging fibres, conductive fibres, and many other functional fibres raise in their importance nowadays. Especially the dispersion quality is essential for the final enhancement of the filament propertied. In this paper, the dispersion of carbon nanoparticles in polymer melt is enhanced by a newly developed sonication unit of ITA and BANDELIN electronic GmbH & Co. KG. The first development steps of the unit fabrication, as well as the first experimental results of the modification of the dispersion, are shown. Special focus will be laid on the sealing of the new sonication unit as well as the positioning and equipment size when being implemented in an existing melt spinning unit. Furthermore, the influence on the thereby manufactured nano-modified filaments will be shown.Keywords: dispersion, sonication, carbon nanoparticles, filaments
Procedia PDF Downloads 301914 Characteristics of Speed Dispersion in Urban Expressway
Authors: Fujian Wang, Shubin Ruan, Meiwei Dai
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Speed dispersion has tight relation to traffic safety. In this paper, several kinds of indicating parameters (the standard speed deviation, the coefficient of variation, the deviation of V85 and V15, the mean speed deviations, and the difference between adjacent car speeds) are applied to investigate the characteristics of speed dispersion, where V85 and V15 are 85th and 15th percentile speed, respectively. Their relationships are into full investigations and the results show that: there exists a positive relation (linear) between mean speed and the deviation of V85 and V15; while a negative relation (quadratic) between traffic flow and standard speed deviation. The mean speed deviation grows exponentially with mean speed while the absolute speed deviation between adjacent cars grows linearly with the headway. The results provide some basic information for traffic management.Keywords: headway, indicating parameters, speed dispersion, urban expressway
Procedia PDF Downloads 352913 Reduced General Dispersion Model in Cylindrical Coordinates and Isotope Transient Kinetic Analysis in Laminar Flow
Authors: Masood Otarod, Ronald M. Supkowski
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This abstract discusses a method that reduces the general dispersion model in cylindrical coordinates to a second order linear ordinary differential equation with constant coefficients so that it can be utilized to conduct kinetic studies in packed bed tubular catalytic reactors at a broad range of Reynolds numbers. The model was tested by 13CO isotope transient tracing of the CO adsorption of Boudouard reaction in a differential reactor at an average Reynolds number of 0.2 over Pd-Al2O3 catalyst. Detailed experimental results have provided evidence for the validity of the theoretical framing of the model and the estimated parameters are consistent with the literature. The solution of the general dispersion model requires the knowledge of the radial distribution of axial velocity. This is not always known. Hence, up until now, the implementation of the dispersion model has been largely restricted to the plug-flow regime. But, ideal plug-flow is impossible to achieve and flow regimes approximating plug-flow leave much room for debate as to the validity of the results. The reduction of the general dispersion model transpires as a result of the application of a factorization theorem. Factorization theorem is derived from the observation that a cross section of a catalytic bed consists of a solid phase across which the reaction takes place and a void or porous phase across which no significant measure of reaction occurs. The disparity in flow and the heterogeneity of the catalytic bed cause the concentration of reacting compounds to fluctuate radially. These variabilities signify the existence of radial positions at which the radial gradient of concentration is zero. Succinctly, factorization theorem states that a concentration function of axial and radial coordinates in a catalytic bed is factorable as the product of the mean radial cup-mixing function and a contingent dimensionless function. The concentration of adsorbed compounds are also factorable since they are piecewise continuous functions and suffer the same variability but in the reverse order of the concentration of mobile phase compounds. Factorability is a property of packed beds which transforms the general dispersion model to an equation in terms of the measurable mean radial cup-mixing concentration of the mobile phase compounds and mean cross-sectional concentration of adsorbed species. The reduced model does not require the knowledge of the radial distribution of the axial velocity. Instead, it is characterized by new transport parameters so denoted by Ωc, Ωa, Ωc, and which are respectively denominated convection coefficient cofactor, axial dispersion coefficient cofactor, and radial dispersion coefficient cofactor. These cofactors adjust the dispersion equation as compensation for the unavailability of the radial distribution of the axial velocity. Together with the rest of the kinetic parameters they can be determined from experimental data via an optimization procedure. Our data showed that the estimated parameters Ωc, Ωa Ωr, are monotonically correlated with the Reynolds number. This is expected to be the case based on the theoretical construct of the model. Computer generated simulations of methanation reaction on nickel provide additional support for the utility of the newly conceptualized dispersion model.Keywords: factorization, general dispersion model, isotope transient kinetic, partial differential equations
Procedia PDF Downloads 269912 Grating Scale Thermal Expansion Error Compensation for Large Machine Tools Based on Multiple Temperature Detection
Authors: Wenlong Feng, Zhenchun Du, Jianguo Yang
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To decrease the grating scale thermal expansion error, a novel method which based on multiple temperature detections is proposed. Several temperature sensors are installed on the grating scale and the temperatures of these sensors are recorded. The temperatures of every point on the grating scale are calculated by interpolating between adjacent sensors. According to the thermal expansion principle, the grating scale thermal expansion error model can be established by doing the integral for the variations of position and temperature. A novel compensation method is proposed in this paper. By applying the established error model, the grating scale thermal expansion error is decreased by 90% compared with no compensation. The residual positioning error of the grating scale is less than 15um/10m and the accuracy of the machine tool is significant improved.Keywords: thermal expansion error of grating scale, error compensation, machine tools, integral method
Procedia PDF Downloads 364911 Research on Transverse Ecological Compensation Mechanism in Yangtze River Economic Belt Based on Evolutionary Game Theory
Authors: Tingyu Zhang
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The cross-basin ecological compensation mechanism is key to stimulating active participation in ecological protection across the entire basin. This study constructs an evolutionary game model of cross-basin ecological compensation in the Yangtze River Economic Belt (YREB), introducing a central government constraint and incentive mechanism (CGCIM) to explore the conditions for achieving strategies of protection and compensation that meet societal expectations. Furthermore, using a water quality-water quantity model combined with factual data from the YREB in 2020, the amount of ecological compensation is calculated. The results indicate that the stability of the evolutionary game model of the upstream and downstream governments in the YREB is closely related to the CGCIM. When the sum of the central government's reward amount to the upstream government and the penalty amount to both sides simultaneously is greater than 39.948 billion yuan, and the sum of the reward amount to the downstream government and the penalty amount to only the lower reaches is greater than 1.567 billion yuan, or when the sum of the reward amount to the downstream government and the penalty amount to both sides simultaneously is greater than 1.567 billion yuan, and the sum of the reward amount to the upstream government and the penalty amount to only the upstream government is greater than 399.48 billion yuan, the protection and compensation become the only evolutionarily stable strategy for the evolutionary game system composed of the upstream and downstream governments in the YREB. At this point, the total ecological compensation that the downstream government of the YREB should pay to the upstream government is 1.567 billion yuan, with Hunan paying 0.03 billion yuan, Hubei 2.53 billion yuan, Jiangxi 0.18 billion yuan, Anhui 1.68 billion yuan, Zhejiang 0.75 billion yuan, Jiangsu 6.57 billion yuan, and Shanghai 3.93 billion yuan. The research results can provide a reference for promoting the improvement and perfection of the cross-basin ecological compensation system in the YREB.Keywords: ecological compensation, evolutionary game model, central government constraint and incentive mechanism, Yangtze river economic belt
Procedia PDF Downloads 64910 A Case Study at PT Bank XYZ on The Role of Compensation, Career Development, and Employee Engagement towards Employee Performance
Authors: Ahmad Badawi Saluy, Novawiguna Kemalasari
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This study aims to examine, analyze and explain the impacts of compensation, career development and employee engagement to employee’s performance partially and simultaneously (Case Study at PT Bank XYZ). The research design used is quantitative descriptive research causality involving 30 respondents. Sources of data are from primary and secondary data, primary data obtained from questionnaires distribution and secondary data obtained from journals and books. Data analysis used model test using smart application PLS 3 that consists of test outer model and inner model. The results showed that compensation, career development and employee engagement partially have a positive impact on employee performance, while they have a positive and significant impact on employee performance simultaneously. The independent variable has the greatest impact is the employee engagement.Keywords: compensation, career development, employee engagement, employee performance
Procedia PDF Downloads 150909 Simple Multipath Compensation for Frequency Modulated Signals: A Case of Radio Frequency vs. Quadrature Baseband
Authors: Lusungu Ndovi
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Radio propagation from point-to-point is affected by the physical channel in many ways. A signal arriving at a destination travels through a number of different paths which are referred to as multi-paths. Research in this area of wireless communications has progressed well over the years with the research taking different angles of focus. By this is meant that some researchers focus on ways of reducing or eluding Multipath effects whilst others focus on ways of mitigating the effects of Multipath through compensation schemes. Baseband processing is seen as one field of signal processing that is cardinal to the advancement of software-defined radio technology. This has led to wide research into the carrying out certain algorithms at baseband. This paper considers compensating for Multipath for Frequency Modulated signals. The compensation process is carried out at Radio frequency (RF) and at Quadrature baseband (QBB) and the results are compared. Simulations are carried out using MatLab so as to show the benefits of working at lower QBB frequencies than at RF.Keywords: quadrature baseband, qadio frequency, qultipath compensation, frequency qodulation, signal processing
Procedia PDF Downloads 479908 Eye Diagram for a System of Highly Mode Coupled PMD/PDL Fiber
Authors: Suad M. Abuzariba, Liang Chen, Saeed Hadjifaradji
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To evaluate the optical eye diagram due to polarization-mode dispersion (PMD), polarization-dependent loss (PDL), and chromatic dispersion (CD) for a system of highly mode coupled fiber with lumped section at any given optical pulse sequence we present an analytical modle. We found that with considering PDL and the polarization direction correlation between PMD and PDL, a system with highly mode coupled fiber with lumped section can have either higher or lower Q-factor than a highly mode coupled system with same root mean square PDL/PMD values. Also we noticed that a system of two highly mode coupled fibers connected together is not equivalent to a system of highly mode coupled fiber when fluctuation is consideredKeywords: polarization mode dispersion, polarization dependent loss, chromatic dispersion, optical eye diagram
Procedia PDF Downloads 864907 Pollutant Dispersion in Coastal Waters
Authors: Sonia Ben Hamza, Sabra Habli, Nejla Mahjoub Saïd, Hervé Bournot, Georges Le Palec
Abstract:
This paper spots light on the effect of a point source pollution on streams, stemming out from intentional release caused by unconscious facts. The consequences of such contamination on ecosystems are very serious. Accordingly, effective tools are highly demanded in this respect, which enable us to come across an accurate progress of pollutant and anticipate different measures to be applied in order to limit the degradation of the environmental surrounding. In this context, we are eager to model a pollutant dispersion of a free surface flow which is ejected by an outfall sewer of an urban sewerage network in coastal water taking into account the influence of climatic parameters on the spread of pollutant. Numerical results showed that pollutant dispersion is merely due to the presence of vortices and turbulence. Hence, it was realized that the pollutant spread in seawater is strongly correlated with climatic conditions in this region.Keywords: coastal waters, numerical simulation, pollutant dispersion, turbulent flows
Procedia PDF Downloads 512906 Effect of DG Installation in Distribution System for Voltage Monitoring Scheme
Authors: S. R. A. Rahim, I. Musirin, M. M. Othman, M. H. Hussain
Abstract:
Loss minimization is a long progressing issue mainly in distribution system. Nevertheless, its effect led to temperature rise due to significant voltage drop through the distribution line. Thus, compensation scheme should be proper scheduled in the attempt to alleviate the voltage drop phenomenon. Distributed generation has been profoundly known for voltage profile improvement provided that over-compensation or under-compensation phenomena are avoided. This paper addresses the issue of voltage improvement through different type DG installation. In ensuring optimal sizing and location of the DGs, predeveloped EMEFA technique was made to be used for this purpose. Incremental loading condition subjected to the system is the concern such that it is beneficial to the power system operator.Keywords: distributed generation, EMEFA, power loss, voltage profile
Procedia PDF Downloads 366