- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2019 22nd International Conference on Computer and Information Technology (ICCIT) - Dhaka, Bangladesh (2019.12.18-2019.12.20)] 2019 22nd International Conference on Computer and Information Technology (ICCIT) - Enhancement of Conversion Efficiency of CdS-CdTe Photovoltaic Cell Sandwiching Intrinsic CdTe Layer between Window and Absorber Layers
摘要： Studies involving turbulent flow have been carried out in many parts of the cardiovascular system, and it has been widely reported that turbulence related to stenosis (narrowing) of arteries creates audible sounds, which may be analyzed to yield information about the nature and severity of the blockage. Results so far indicate that the high frequency content of the sounds generally increases with the degree of stenosis. In this paper, we designed and built an MEMs microphone array and a signal acquisition board to improve the detection of coronary occlusions using an approach based on the recording and analysis of isolated diastolic heart sounds associated with turbulent blood flow in occluded coronary arteries. The nonlinear dynamic analysis method based on approximate entropy has been proposed for the analysis of diastolic heart sounds from patients with single coronary occlusions, before and after stent placement procedures. The nonlinear dynamic analysis (approximate entropy) measures of the diastolic heart sounds recorded from eight patients with single coronary occlusions and two normal subjects were estimated. In addition, a spectral analysis based on the fast Fourier transform was used to estimate the energy content of the recorded signals. Results suggest the presence of high nonlinear (approximate entropy) values of diastolic heart sounds associated with coronary artery disease (p < 0.01) as well as significant differences in the energy content of the heart sound signals above and below 150 Hz (p < 0.05).
关键词： MEMs microphone array,approximate entropy,nonlinear dynamics analysis,Coronary artery disease
更新于2025-09-23 15:21:01
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[IEEE 2019 20th International Conference on Electronic Packaging Technology(ICEPT) - Hong Kong, China (2019.8.12-2019.8.15)] 2019 20th International Conference on Electronic Packaging Technology(ICEPT) - Effects of Cracks on Interfacial Thermal Properties of LED Packages by Entropy Generation
摘要： Entropy generation is a kind of available energy loss. Evolution of thermodynamic entropy during accelerated test of die attach in LED is studied with transient analysis. The existing models on the study of heat transfer in the solder layer, mainly including the effect of voids on the mechanical properties and the heat transfer performance. However, there are few investigations that relating the second law of thermodynamics to the voids in the DA layer, transient heat distribution is less considered. In this work, based on the temperature distribution, the convection entropy rate of the chip to the ambient and the conduction entropy of the DA layer are studied. The results show that, as the length of the crack increases, both the convection entropy rate and the conduction entropy increase. Particularly, when the crack length was increased from 30% to 40%, the normalized conduction entropy of the DA layer showed a sharp increase, which indicates that the large crack (more than 30%) will pose a serious challenge to the quality of the LED packaging.
关键词： thermal effect,DA layer,cracking,transient,entropy generation
更新于2025-09-23 15:21:01
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Bayesian High Resolution Range Profile Reconstruction of High-Speed Moving Target From Under-Sampled Data
摘要： Obtained by wide band radar system, high resolution range profile (HRRP) is the projection of scatterers of target to the radar line-of-sight (LOS). HRRP reconstruction is unavoidable for inverse synthetic aperture radar (ISAR) imaging, and of particular usage for target recognition, especially in cases that the ISAR image of target is not able to be achieved. For the high-speed moving target, however, its HRRP is stretched by the high order phase error. To obtain well-focused HRRP, the phase error induced by target velocity should be compensated, utilizing either measured or estimated target velocity. Noting in case of under-sampled data, the traditional velocity estimation and HRRP reconstruction algorithms become invalid, a novel HRRP reconstruction of high-speed target for under-sampled data is proposed. The Laplacian scale mixture (LSM) is used as the sparse prior of HRRP, and the variational Bayesian inference is utilized to derive its posterior, so as to reconstruct it with high resolution from the under-sampled data. Additionally, during the reconstruction of HRRP, the target velocity is estimated via joint constraint of entropy minimization and sparseness of HRRP to compensate the high order phase error brought by the target velocity to concentrate HRRP. Experimental results based on both simulated and measured data validate the effectiveness of the proposed Bayesian HRRP reconstruction algorithm.
关键词： inverse synthetic aperture radar (ISAR) imaging,entropy minimization,Newton method,variational Bayesian inference,High resolution range profile (HRRP),under-sampled data,velocity estimation
更新于2025-09-23 15:21:01
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Configurational entropy of optical bright similariton in tapered graded-index waveguide
摘要： Con?gurational entropy (CE) consists of a family of entropic measures of information used to describe the shape complexity of spatially-localized functions with respect to a set of parameters. We obtain the Differential Con?gurational Entropy (DCE) for similariton waves traveling in tapered graded-index optical waveguides modeled by a generalized nonlinear Schr?dinger equation. It is found that for similariton’s widths lying within a certain range, DCE attains minimum saturation values as the nonlinear wave evolves along the effective propagation variable ζ (t). In particular, saturation is achieved earlier for lower values of the width, which we show correspond to global minima of the DCE. Such low entropic values lead to minimum dispersion of momentum modes as the similariton waves propagate along tapered graded-index waveguides, and should be of importance in guiding their design.
关键词： Optical ?ber communications,Tapered graded-index waveguide,Bright similariton,Con?gurational entropy,Generalized nonlinear Schr?dinger equation
更新于2025-09-23 15:21:01
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Wehrl entropy based quantification of nonclassicality for single mode quantum optical states
摘要： Nonclassical states of a quantized light are described in terms of Glauber-Sudarshan P distribution which is not a genuine classical probability distribution. Despite several attempts, defining a uniform measure of nonclassicality (NC) for the single mode quantum states of light is yet an open task. In our previous work [Phys. Rev. A 95, 012330 (2017)] we have shown that the existing well-known measures fail to quantify the NC of single mode states that are generated under multiple NC-inducing operations. In this paper, we propose a new quantification of NC for the single mode quantum states as the difference between the total Wehrl entropy of the state and the maximum Wehrl entropy arising due to its classical characteristics. The classical reference state is chosen at the same randomness, given by the von-Neumann entropy, as the state itself. We further suggest operational interpretation of the proposed measure in terms of phase-space sampling entropy as well as potential to generate entanglement, in the case of pure states. We obtain analytic expressions of NC for pure states and Gaussian mixed states. We show that, along with the states generated under single NC-inducing operations, also for the broader class of states that are generated under multiple NC-inducing operations, our quantification enumerates the NC consistently. However, the evaluation of NC for the non-Gaussian mixed states is subject to extensive numerical computation that lies beyond the scope of the current work. We finally conclude with certain open questions.
关键词： Wehrl Entropy,Quantumness,Phase Space Distributions,Quantum Optics,Nonclassicality
更新于2025-09-23 15:21:01
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[IEEE 2018 IEEE 3rd International Conference on Image, Vision and Computing (ICIVC) - Chongqing (2018.6.27-2018.6.29)] 2018 IEEE 3rd International Conference on Image, Vision and Computing (ICIVC) - Voice Pathology Detection Based on the Vocal Fold Signal and the Vocal Tract Signal Separation
摘要： Voice pathology correlates with vocal fold problems, so extracting valid features from the vocal fold excitation signal is helpful for classifying the normal and pathological voice. A novel feature extraction method which combines wavelet packet decomposition and nonlinear feature extraction is proposed in this paper. The original speech signals are firstly decomposed into 5 layers using wavelet packet-based method, and the high frequency signals which correlate with the vocal fold are reconstructed. Then nonlinear features are extracted from the reconstructed signals. Support Vector Machine is used to classify the normal and pathological voice using the nonlinear features. The proposed method and features are evaluated on the Massachusetts Eye and Ear Infirmary databases. The second-order renyi entropy features give very promising classification accuracy of 98.21%. The highest accuracy is 99.21% when the Hurst parameter and second-order renyi entropy features are combined. Experimental results show that the vocal fold excitation signal can express the pathological information about sound efficiently, which can be used for the automatic detection and classification of the pathological voice.
关键词： support vector machine,wavelet packet,entropy,vocal fold excitation
更新于2025-09-23 15:21:01
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[IEEE 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - Rome, Italy (2019.6.17-2019.6.20)] 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - High-Enthalpy Flow Investigations by UV Laser-Induced Fluorescence
摘要： With the advance of software receiver, multipath estimation becomes a key issue for high accuracy positioning systems. It is crucial for eliminating the multipath error and improving the positioning accuracy to estimate multipath parameters. The accessible multipath estimation algorithms are usually designed for Gaussian noise, and their performances degrade dramatically in non-Gaussian noise, since the mean square error criterion is adopted. To tackle the problem, a new filter based on centered error entropy criterion (CEEC) is proposed for multipath estimation. In the proposed filter, the CEEC is considered as a performance index, which is not limited to the assumption of Gaussian and linearity. According to a stochastic information gradient method, an optimal filer gain matrix is obtained by maximizing the performance function of centered error entropy. Meanwhile, a convergence analysis of the proposed filter is offered. Furthermore, a recursive estimation method based on modified Parzen windowing technique is proposed for practical implementation. The simulation results indicate that the proposed filter outperforms the filter based on minimum error entropy criterion for multipath estimation.
关键词： stochastic information gradient (SIG),minimum error entropy criterion (MEEC),centered error entropy criterion (CEEC),Multipath estimation
更新于2025-09-23 15:19:57
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Evaluation of performance of near-field thermophotovoltaic systems based on entropy analysis
摘要： Near-field radiative heat transfer can significantly improve the output power of thermophotovoltaic (TPV) systems. Therefore, it is crucial to explore how to increase the energy conversion efficiencies of near-field TPV systems. In this study, based on the fluctuation–dissipation theorem with the effective medium theory, we evaluate the performance of a near-field TPV system from the formulation of thermodynamics. It is found that a near-field TPV system consisting of InAs or GaSb cell can achieve higher heat flux or efficiency limit, respectively. Moreover, the TPV system with a hyperbolic metamaterial (HMM) emitter composed of nanowire or nanohole arrays can achieve higher heat flux and efficiency limit compared to that of the bulk reference. This is attributable to the HMMs being able to support hyperbolic modes, and the radiation with the HMM emitter exhibits a favorable entropy content for the energy conversion efficiency. This work provides an approach to determine the efficiency limit and establish a target for efficiency of the near-field TPV system without considering how the system works. The results of this study will facilitate the design and application of the HMM emitter and material of the TPV cell to improve the efficiency of near-field TPV systems.
关键词： Thermophotovoltaic systems,Near-field radiative heat transfer,Energy conversion efficiency,Hyperbolic metamaterial,Entropy analysis
更新于2025-09-23 15:19:57
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Probing exciton/exciton interactions with entangled photons: Theory
摘要： Quantum entangled photons provide a sensitive probe of many-body interactions and offer a unique experimental portal for quantifying many-body correlations in a material system. In this paper, we present a theoretical demonstration of how photon–photon entanglement can be generated via interactions between coupled qubits. Here, we develop a model for the scattering of an entangled pair of photons from a molecular dimer. We develop a diagrammatic theory for the scattering matrix and show that one can correlate the von Neumann entropy of the outgoing bi-photon wave function with exciton exchange and repulsion interactions. We conclude by discussing possible experimental scenarios for realizing these ideas.
关键词： exciton exchange,repulsion interactions,quantum entangled photons,von Neumann entropy,many-body interactions
更新于2025-09-23 15:19:57
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Observation of Dislocations in Graded Buffer Layers of IMM Single Junction InGaAs Solar Cells by Two-Photon Excitation Photoluminescence
摘要： In binary classi?cation, two-way confusion matrices, with corresponding measures, such as sensitivity and speci?city, have become so ubiquitous that those who review results may not realize there are other and more realistic ways to visualize data. This is, particularly, true when risk and reward considerations are important. The approach suggested here proposes that classi?cation need not offer a conclusion on every instance within a data set. If an algorithm ?nds instances (e.g., patient cases in a medical data set) in which attributes pertaining to a patient’s disease offer zero to nil information, there should be no classi?cation offered. From the physician’s perspective, disclosure of nil information should be welcome because it might prevent potentially harmful treatment. It follows from this that the developer of a classi?er can provide summary results amendable for helping the consumer decide whether or not it is prudent to pass or act (commission versus omission). It is not always about balancing sensitivity and speci?city in all cases, but optimizing action on some cases. The explanation is centered on John Kelly’s link of gambling with Shannon information theory. In addition, Graham’s margin of safety, Bernoulli’s utiles, and Hippocratic Oath are important. An example problem is provided using a Netherlands Cancer Institute breast cancer data set. Recurrence score, a popular molecular-based assay for breast cancer prognosis, was found to have an uninformative zone. The uninformative subset had been grouped with positive results to garner higher sensitivity. Yet, because of a positive result, patients might be advised to undergo potentially harmful treatment in the absence of useful information.
关键词： data compression,cancer,clinical diagnosis,sensitivity and speci?city,Data analysis,genetic expression,entropy
更新于2025-09-23 15:19:57