23,997 research outputs found
Dispersive shock waves in the Kadomtsev-Petviashvili and Two Dimensional Benjamin-Ono equations
Dispersive shock waves (DSWs) in the Kadomtsev-Petviashvili (KP) equation and
two dimensional Benjamin-Ono (2DBO) equation are considered using parabolic
front initial data. Employing a front tracking type ansatz exactly reduces the
study of DSWs in two space one time (2+1) dimensions to finding DSW solutions
of (1+1) dimensional equations. With this ansatz, the KP and 2DBO equations can
be exactly reduced to cylindrical Korteweg-de Vries (cKdV) and cylindrical
Benjamin-Ono (cBO) equations, respectively. Whitham modulation equations which
describe DSW evolution in the cKdV and cBO equations are derived in general and
Riemann type variables are introduced. DSWs obtained from the numerical
solutions of the corresponding Whitham systems and direct numerical simulations
of the cKdV and cBO equations are compared with excellent agreement obtained.
In turn, DSWs obtained from direct numerical simulations of the KP and 2DBO
equations are compared with the cKdV and cBO equations, again with remarkable
agreement. It is concluded that the (2+1) DSW behavior along parabolic fronts
can be effectively described by the DSW solutions of the reduced (1+1)
dimensional equations.Comment: 25 Pages, 16 Figures. The movies showing dispersive shock wave
propagation in Kadomtsev-Petviashvili II and Two Dimensional Benjamin-Ono
equations are available at https://youtu.be/AExAQHRS_vE and
https://youtu.be/aXUNYKFlke
S-wave charmed mesons in lattice NRQCD
Heavy-light mesons can be studied using the 1/M expansion of NRQCD, provided
the heavy quark mass is sufficiently large. Calculations of the S-wave charmed
meson masses from a classically and tadpole-improved action are presented. A
comparison of O(1/M), O(1/M^2) and O(1/M^3) results allows convergence of the
expansion to be discussed. It is shown that the form of discretized heavy quark
propagation must be chosen carefully.Comment: LATTICE98(heavyqk), 3 pages including 3 figure
Experimental investigation of the energy performance of a novel Micro-encapsulated Phase Change Material (MPCM) slurry based PV/T system
© 2015 Elsevier Ltd. As a follow-on work of the authors' theoretical study, the paper presented an experimental investigation into the energy performance of a novel PV/T thermal and power system employing the Micro-encapsulated Phase Change Material (MPCM) slurry as the working fluid. A prototype PV/T module of 800mmĂ1600mmĂ50mm was designed and constructed based on the previous modelling recommendation. The performance of the PV/T module and associated thermal and power system were tested under various solar radiations, slurry Reynolds numbers and MPCM concentrations. It was found that (1) increasing solar radiation led to the increased PV/T module temperature, decreased solar thermal and electrical efficiencies and reduced slurry pressure drop; (2) increasing the slurry Reynolds number led to the increased solar thermal and electrical efficiencies, decreased module temperature, and increased pressure drop; and (3) increasing the MPCM concentration led to the reduced module temperature and increased pressure drop. The experimental results were used to examine the accuracy of the established computer model, giving a derivation scale ranging from 1.1% to 6.1% which is an acceptable error level for general engineering simulation. The recommended operational conditions of the PV/T system were (1) MPCM slurry weight concentration of 10%, (2) slurry Reynolds number of 3000, and (3) solar radiation of 500-700W/m 2 ; at which the system could achieve the net overall solar efficiencies of 80.8-83.9%. To summarise, the MPCM slurry based PV/T thermal and power system is superior to conventional air-sourced heat pump systems (ASHP) and solar assisted heat pump systems (ISAHP), and has the potential to help reduce fossil fuel consumption and carbon emission to the environment
Investigation of electrical properties for cantilever-based piezoelectric energy harvester
In the present era, the renewable sources of energy, e.g., piezoelectric materials are in great demand. They play a vital role in the field of micro-electromechanical systems, e.g., sensors and actuators. The cantilever-based piezoelectric energy harvesters are very popular because of their high performance and utilization. In this research-work, an energy harvester model based on a cantilever beam with bimorph PZT-5A, having a substrate layer of structural steel, was presented. The proposed energy scavenging system, designed in COMSOL Multiphysics, was applied to analyze the electrical output as a function of excitation frequencies, load resistances and accelerations. Analytical modeling was employed to measure the output voltage and power under pre-defined conditions of acceleration and load resistance. Experimentation was also performed to determine the relationship between independent and output parameters. Energy harvester is capable of producing the maximum power of 1.16 mW at a resonant frequency of 71 Hz under 1g acceleration, having load resistance of 12 k Omega. It was observed that acceleration and output power are directly proportional to each other. Moreover, the investigation conveys that the experimental results are in good agreement with the numerical results. The maximum error obtained between the experimental and numerical investigation was found to equal 4.3%
THE MODERATING ROLE OF CORPORATE IMAGE BETWEEN USER EXPERIENCE TOWARDS CUSTOMER LOYALTY: A STUDY ON INDIHOME BY TELKOM INDONESIA
The research titled â
(2013).
This study aims to
Tarus and Rabach
ABSTRACT
The Moderating Role of Corporate Image Between
Influencing Factor of User Experience into Customer Loyalty: A Study on Indihome By Telkom Indonesiaâ has two variables and a moderator. The Independent variable; User Experience (X) that consists of Service Value, Service Quality, Customer Satisfaction, and Social Pressure. The Dependent Variable; Customer Loyalty (Y) that is customer loyalty. This research has a moderating role
of corporate image (M). All of those variables are adapted from
examine the influence of user experience towards
customers loyalty as well as examines the moderating role of corporate image towards user experience towards customers loyalty of PT. Telekomunikasi
Indonesia.
The population used in this study are the customers of Indihome by PT.
Non-Probability Sampling that gathers data from 400 respondents. This study conducted within
August 2017 until April 2018.
The research reveals that Service Value, Customer Satisfaction and Social Pressure are predictors of customer loyalty of Indihome. Furthermore, Social Pressure is the most powerful predictor compared to other predictors. The role of corporate image is proven to have a positive effect of moderator in between; Service Value towards Customer Loyalty, Customer Satisfaction towards Customer Loyalty, and Social Pressure towards Customer Loyalty.
Keywords: Service Value, Service Quality, Customer Satisfaction, Social Pressure, Corporate Image, Customer loyalty
The Place and Importance of Associations in Strengthening Trade Unions
Developments in the globalization process play an important role in the power loss of trade unions. This situation reveals the problems of unionization in the current industrial relations system. At this point, associations with aspects similar to the trade unions and important non-governmental organizations (NGOs), have an important place in terms of understanding the position, the importance, and the functions of today's industrial relations system where different ways of solutions are sought for unionism. In this context, this investigation focuses on the role, importance and functions of associations in the protection and reinforcement of the existing forces of the trade unions.The investigation aims to evaluate the position, importance and the potential functions of the associations in development of new strategies for strengthening the trade unions, and to suggest new ideas on this direction. The topic (in the direction of the determined purpose) was evaluated under the titles of âchange and transformation in trade unionismâ, ânew strategies discussed and developed in the process of strengthening the trade unionsâ, and âthe associations in development of new strategiesâ. According to basic findings, in the process of the re-empowerment of trade unions, associations are emerging as important NGOs in the realization of positive scenarios and taking precautions against negative scenarios. In conclusion; besides unionization, importance should be attached to association in every matter. In this process, associations should function in the independent status, in the dependent status, and in the core status
Urban Form and Structure Explain Variability in Spatial Inequality of Property Flood Risk among US Counties
Understanding the relationship between urban form and structure and spatial
variation of property flood risk has been a longstanding challenge in urban
planning and city flood risk management. Yet limited data-driven insights exist
regarding the extent to which variation in spatial inequality of property flood
risk in cities can be explained by heterogenous features of urban form and
structure. In this study, we explore eight key features (i.e., population
density, point of interest density, road density, minority segregation, income
segregation, urban centrality index, gross domestic product, and human mobility
index) related to urban form and structure to explain variability in spatial
inequality of property flood risk among 2567 US counties. Using rich datasets
related to property flood risk, we quantify spatial inequality in property
flood risk and delineate features of urban form and structure using
high-resolution human mobility and facility distribution data. We identify
significant variation in spatial inequality of property flood risk among US
counties with coastline and metropolitan counties having the greatest spatial
inequality of property flood risk. The results also reveal variations in
spatial inequality of property flood risk can be effectively explained based on
principal components of development density, economic activity, and centrality
and segregation. Using a classification and regression tree model, we
demonstrate how these principal components interact and form pathways that
explain levels of spatial inequality in property flood risk in US counties. The
findings offer important insights for the understanding of the complex
interplay between urban form and structure and spatial inequality of property
flood risk and have important implications for integrated urban design
strategies to address property flood risk as cities continue to expand and
develop
solveME: fast and reliable solution of nonlinear ME models.
BackgroundGenome-scale models of metabolism and macromolecular expression (ME) significantly expand the scope and predictive capabilities of constraint-based modeling. ME models present considerable computational challenges: they are much (>30 times) larger than corresponding metabolic reconstructions (M models), are multiscale, and growth maximization is a nonlinear programming (NLP) problem, mainly due to macromolecule dilution constraints.ResultsHere, we address these computational challenges. We develop a fast and numerically reliable solution method for growth maximization in ME models using a quad-precision NLP solver (Quad MINOS). Our method was up to 45 % faster than binary search for six significant digits in growth rate. We also develop a fast, quad-precision flux variability analysis that is accelerated (up to 60Ă speedup) via solver warm-starts. Finally, we employ the tools developed to investigate growth-coupled succinate overproduction, accounting for proteome constraints.ConclusionsJust as genome-scale metabolic reconstructions have become an invaluable tool for computational and systems biologists, we anticipate that these fast and numerically reliable ME solution methods will accelerate the wide-spread adoption of ME models for researchers in these fields
Inclusive CP Asymmetries in Semileptonic Decays of B Mesons
We estimate the sensitivity of single lepton CP violation measurements with
respect to that of traditional di-lepton measurements. We find that the
sensitivity of the single lepton method is better than that of the di-lepton
method. The achievable sensitivity with the currently available data is already
in the range relevant to standard model predictions. We also give general
expressions for inclusive decay time distributions on where the
other is not measured, which will be used to obtain time dependent
asymmetries. The expression is of general use whenever one deals with inclusive
time-dependent as well as time-integrated measurements in where the final state of the other is not reconstructed or
when only the time difference is measured.Comment: 7 pages, 1 figure. Two references added, and a few typos correcte
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