162 research outputs found
Synchronization dynamics of two nanomechanical membranes within a Fabry-Perot cavity
Spontaneous synchronization is a significant collective behavior of weakly
coupled systems. Due to their inherent nonlinear nature, optomechanical systems
can exhibit self-sustained oscillations which can be exploited for
synchronizing different mechanical resonators. In this paper, we explore the
synchronization dynamics of two membranes coupled to a common optical field
within a cavity, and pumped with a strong blue-detuned laser drive. We focus on
the system quantum dynamics in the parameter regime corresponding to
synchronization of the classical motion of the two membranes. With an
appropriate definition of the phase difference operator for the resonators, we
study synchronization in the quantum case through the covariance matrix
formalism. We find that for sufficiently large driving, quantum synchronization
is robust with respect to quantum fluctuations and to thermal noise up to not
too large temperatures. Under synchronization, the two membranes are never
entangled, while quantum discord behaves similarly to quantum synchronization,
that is, it is larger when the variance of the phase difference is smaller
The comparison of under-5-year nutritional status among Fars-native, Turkman and Sistani ethnic groups in the north of Iran
Background: Under nutrition is a health problem in developing countries and the main aim of this study was determine of the nutritional status and some sociodemographic factors among rural under-5-year children in the North of Iran in 2013. Methods: This was a descriptive, cross-sectional study, which carried out on 2530 children (637 = Fars-native, 1002 = Turkman and 891 = Sistani) from 21 villages in the North of Iran. Villages were chosen by random sampling among 118, and all of under-five children were chosen by simple sampling. For all of cases, a questionnaire with contain questions on the socialdemographic condition was completed and anthropometric indexes were measured by a learned team. Anthropometric data were compared with those in Centers for Disease Control and Prevention reference population. SPSS 18.0 software was used for statistical data analysis and P value under 0.05 included significations. Results: Generally, under nutrition (Z-score ≤ −2) was observed in 6.6%, 18.5% and 3.3% based on underweight, stunting and wasting, respectively and there were in boys more than girls and in Sistani more than other ethnic groups. Based on underweight and stunting, under nutrition was seen in Sistani more than other ethnic groups. Among three ethnic groups, stunting was significant both in boys (P = 0.013) and in girls (P = 0.004), but wasting was significant only in girls (P = 0.001). The estimated odds ratio (OR) with 95% confidence interval of under nutrition was obtained from logistic regression. Compared with good economic group, the OR was 1.831 in poor economic groups (P = 0.001). The risk of under nutrition in Sistanish ethnic group was 1.754 times more than Fars-native group (P = 0.001). Conclusions: Under nutrition is a health problem among under-5-year children in rural area in the North of Iran and stunting was seen in an alarming rate among them. Among ethnic groups, Sistanish children more than others were under nourished. Poor economic status is a risk factor for under nutrition in this area. © 2015 Veghari G
Interrelationships of emotional intelligence with the awareness of request and apology strategies in an EFL setting
Taking the approach of interlanguage pragmatic analysis based on the theories of Speech Acts and Emotional Intelligence (EI), the main purpose of the present study was to find the interrelationships among components of EI, and awareness of request and apology strategies among Iranian TEFL students. The study was conducted on 200 English teaching majors from Mashhad universities. EI was measured through a translated form of Bar-On emotional quotient inventory and a self-developed questionnaire for measuring the apology and request strategies. The results of path analysis showed that among five sub-constructs of EI, four variables positively and significantly predict request strategies: Interpersonal (β= .40, p.05), Intrapersonal (β= .16, p.05), Adaptability (β= .17, p.05), and Stress management (β= .15, p.05). Moreover, among five sub-constructs of EI, three variables of Interpersonal (β= .16, p.05), Intrapersonal (β= .22, p.05), and Stress management (β= .12, p.05) are predictors of apology strategy. The results also indicate that the proposed model had a perfect fit with the empirical data. Furthermore, the results of correlation showed that General Mood is positively and significantly correlated with apology and request. Thus, it is suggested that educators and policymakers consider the importance of EI in improving request and apology strategies
Automatic generation and verification of railway interlocking control tables using FSM and NuSMV
Due to the important role in providing safe conditions for train movements, railway interlocking systems are considered as safety critical systems. The reliability, safety and integrity of these systems, relies on reliability and integrity of all stages in their lifecycle including the design, verification, manufacture, test, operation and maintenance. In this paper, the automatic generation and verification of interlocking control tables, as one of the most important stages in the interlocking design process has been focused on, by the safety critical research group in the School of Railway Engineering. Three different subsystems including a graphical signalling layout planner, a control table generator and a control table verifier, have been introduced. Using NuSMV model checker, the control table verifier analyzes the contents of control table besides the safe train movement conditions and checks for any
conflicting settings in the table. This includes settings for conflicting routes, signals, points and also settings for route isolation and single and multiple overlap situations. The latest two settings, as route isolation and multiple overlap situations are from new outcomes of the work comparing to works represented on the subject recently
Optimal Huygens' Metasurface for Wireless Power Transfer Efficiency Improvement
In this paper, we investigate the electromagnetic response of a Huygens' metasurface (HMS) embedded between the transmitter and receiver coils of a near field wireless power transfer (WPT) system and their interactions for the feasibility of increasing efficiency. To analyze the proposed configuration, we use the point-dipole approximation to describe the electromagnetic fields and boundary conditions governing HMS to calculate the mutual inductance between the coils and to obtain closed-form analytical expressions. The proposed theory shows that by optimally designing the HMS inclusions, the amplitude of the mutual inductance between the transmitter and receiver coils in the near-field WPT can be increased, resulting in improved efficiency. Finally, by drawing on the proposed theory, we design a thin layer and finite-size HMS consisting of 64 elements. The bianisotropic Omega-type particle is used to design the HMS to improve the efficiency of the sample WPT system at the frequency of 100 MHz. The results of the full-wave simulation show that the power transfer efficiency in the free space increases from 25% to 42% in the presence of the proposed HMS
Small Multi-Band Rectangular Dielectric Resonator Antennas for Personal Communication Devices
The design of a novel rectangular dielectric resonator antenna (DRA) for multi-band application has been presented in this paper. The presented antenna has been composed of very low cost and relatively low dielectric constant substrate materials while three-segment thin dielectrics with different sizes have been used and separated by two metal plates in order to set the four different frequency bands. The proposed quad-band antenna operates at 2.4/3.5/5.2 & 5.8 GHz. The radiation pattern, gain and VSWR of this antenna show very good operation for this antenna in all frequency bands. The first method based on finite element method (FEM) and the second one based on finite integral technique (FIT) have been used to analyze antenna structure, and subsequently the Genetic Algorithm (GA) has been applied by using HFSS simulator to obtain the optimized parameters.DOI:http://dx.doi.org/10.11591/ijece.v4i1.457
The Role of Learning Organizations in Improving Human Resources Management
The rapid pace of changes in internal and external business environment affects the organizations to develop a new strategy such as learning ; in this change process, what is more important is that how organizations struggle to survive and succeed in business environment . The proposed strategy is that organizations develop into learning organizations , in other words , innovations in different dimensions make the organizations to learn as much as or faster than outside environment , in case the organizations do not embrace change and not learn as much as or even more than environmental changes , doubtlessly, they shall be destroyed. Organizational learning in terms of methods, structures within organization encourages the human resources in the organizations. Keywords: Learning, learning Organizations, Human Resource
Affine Frequency Division Multiplexing For Communications on Sparse Time-Varying Channels
This paper addresses channel estimation for linear time-varying (LTV)
wireless propagation links under the assumption of double sparsity i.e.,
sparsity in both the delay and the Doppler domains. Affine frequency division
multiplexing (AFDM), a recently proposed waveform, is shown to be optimal (in a
sense that we make explicit) for this problem. With both mathematical analysis
and numerical results, the minimal pilot and guard overhead needed for
achieving a target mean squared error (MSE) while performing channel estimation
is shown to be the smallest when AFDM is employed instead of both conventional
and recently proposed waveforms.Comment: 6 pages, 9 figures, submitted to Globecom 202
Estimating CO2-Brine diffusivity using hybrid models of ANFIS and evolutionary algorithms
One of the important parameters illustrating the mass transfer process is the diffusion coefficient of carbon dioxide which has a great impact on carbon dioxide storage in marine ecosystems, saline aquifers, and depleted reservoirs. Due to the complex interpretation approaches and special laboratory equipment for measurement of carbon dioxide-brine system diffusivity, the computational and mathematical methods are preferred. In this paper, the adaptive neuro-fuzzy inference system (ANFIS) is coupled with five different evolutionary algorithms for predicting the diffusivity coefficient of carbon dioxide. The R2 values forthe testing phase are 0.9978, 0.9932, 0.9854, 0.9738 and 0.9514 for ANFIS optimized by particle swarm optimization (PSO), genetic algorithms (GA), ant colony optimization (ACO), backpropagation (BP), and differential evolution (DE), respectively. The hybrid machine learning model of ANFIS-PSO outperforms the other models
A quasi-experimental study on the role of multiple intelligences in developing motivational orientation and listening proficiency among Iranian tefl students.
Berasaskan trend semasa dalam pendidikan yang memberi tumpuan atau pemusatan khusus terhadap pelajar, maka Teori Kecerdasan Pelbagai (Multiple Intelligences Theory, MIT) dipercayai dapat membantu para guru menilai perbezaan kognitif dan afektif bagi setiap pelajar ESL/EFL.
Multiple Intelligences Theory (MIT) is believed to provide for teachers to consider ESL/EFL learners’ individual cognitive and affective differences. However, there is no research on cognition and affect in one single study to investigate the problem of listening
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