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Detection probability for moving ground target of normal distribution using infrared satellite
摘要： In this article, we discuss the detection probability for a moving ground target such as vehicles using an infrared imaging satellite. In the ?rst part, we discuss a basic detection model for a regional ground target using a satellite. The probability of detection is calculated. In the second part, a basic model for the recognition of a ground target using an infrared imaging satellite is developed based on the model in the ?rst part. Based above two parts,we discuss a basic model of the detection probability for a moving ground target using an infrared imaging satellite in the third part. As the normal distribution has the maximum entropy, we analyze the normal distribution of a moving ground target such as some vehicles, and based on our conclusions, we develop a basic probability model for the detection of a moving ground target using an infrared imaging satellite. Finally, the simulation was carried on by STK software.
关键词： Moving ground target,Normal distribution,Detection probability,Regional ground target,Infrared light imaging satellite
更新于2025-09-23 15:23:52
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Photobiological properties of phthalocyanine photosensitizers Photosens, Holosens and Phthalosens: A comparative in vitro analysis
摘要： Photobiological properties of phthalocyanine photosensitizers, namely, clinically approved Photosens and new compounds Holosens and Phthalosens were analyzed on transitional cell carcinoma of the urinary bladder (T24) and human hepatic adenocarcinoma (SK-HEP-1). Photosens is a sulfated aluminum phthalocyanine with the number of sulfo groups 3.4, which is characterized by a high degree of hydrophilicity, slow cellular uptake, localization in lysosomes and the lowest photodynamic activity. Holosens is an octacholine zinc phthalocyanine, a cationic compound with significant charge. Holosens more efficiently enters the cells; it is localized in Golgi apparatus in addition to lysosomes and exhibits a significant inhibitory effect on cell viability upon irradiation. The highest photodynamic activity was demostrated by Phthalosens. Phthalosens is a metal-free analog of Photosens with a number of sulfo groups 2.5, which determines its amphiphilicity. Phthalosens is characterized by the highest rate of cellular uptake through the outer cell membrane, localization in cell membrane as well as in lysosomes and Golgi apparatus, and the highest activity upon irradiation among the photosensitizers studied. In general, changes in the physicochemical properties of Holosens and Phthalosens ensured an increase in their efficiency in vitro compared to Photosens. The features of accumulation, intracellular distribution and their interrelation with photodynamic activity, revealed in this work, indicate the prospects of Phthalosens and Holosens for clinical practice.
关键词： Photodynamic treatment,photodynamic activity,Holosens,dark toxicity,Phthalosens,Photosens,intracellular distribution,phthalocyanines
更新于2025-09-23 15:23:52
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An unstructured Monte Carlo ray-tracing method for solving radiative heat transfer in 3D gray semitransparent medium
摘要： Monte Carlo ray-tracing method (MCRTM) is widely used for solving the Radiative Transfer equation (RTE) due to its high accuracy and flexibility. In this paper, a MCRTM is developed for solving the radiative heat transfer in gray semitransparent media with complex geometries which are discretized by 3D unstructured grids. A novel algorithm associated to unstructured four-node tetrahedron element is proposed for generating random emitting positions of rays, and the ray tracing process is performed based on Beer's law. Meanwhile, radiation distribution factors are used for calculating radiative source terms which are loaded to the grid. The present method is first validated by comparing the predictive results with those from previous studies on a cubic enclosure, a 3D L-shaped enclosure, and a 3D elliptical enclosure, respectively. Furthermore, a radiation-conduction heat transfer problem is examined in a cylindrical enclosure. All the comparisons show that the present method is in good agreement with these previous cases. This method can be well adapted to various complex geometries. In addition, since the source term is calculated by the radiation distribution factor, which can be reused for different conditions as long as the volumetric radiative properties remain unchanged, this will bring great advantage when coupled with other heat transfer models such as conduction, convection, combustion, etc.
关键词： Monte Carlo ray-tracing method,Radiative heat transfer,Semitransparent medium,Radiation distribution factor,Unstructured grids
更新于2025-09-23 15:23:52
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A novel approach for in-situ soot size distribution measurement based on spectrally resolved light scattering
摘要： The present study demonstrates the exploitation of the spectral elastic light scattering technique. Additional information provided by the spectral response of the light scattering signals enables the measurement of the soot size distribution with only two scattering angles. It also provides quantitative data on the spectral dependence of the soot optical index, which is related to the soot chemical composition. The measurement principle consists in dividing the scattered spectra collected at two scattering angles and processing this ratio using the Rayleigh–Debye–Gans theory for Fractal Aggregates (RDG-FA). It is shown that the median diameter of gyration and geometric standard deviation of a lognormal soot size distribution can be determined without any prior information on key parameters such as the fractal prefactor, particle primary diameter, aggregate number density and soot optical properties. A proof of concept was performed on soot particles produced by a miniCAST generator by comparing the optical results with the soot size distributions measured by SMPS. A statistical Bayesian inversion approach was used to determine posterior distributions with a particular emphasis on their uncertainty quantification.
关键词： Light scattering,Bayesian,Spectral scattering,Optical properties,Soot,Size distribution
更新于2025-09-23 15:23:52
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[IEEE 2018 7th International Conference on Renewable Energy Research and Applications (ICRERA) - Paris, France (2018.10.14-2018.10.17)] 2018 7th International Conference on Renewable Energy Research and Applications (ICRERA) - Performance-Improved Maximum Power Point Tracking Control for PV System
摘要： Dc distribution systems are gaining attracted because of expanding the utilization of solar photovoltaic (PV) power. In such a situation, the design of the maximum power point tracking (MPPT) controllers should consider not only varying solar irradiance but also the dc bus voltage fluctuation. The purpose of this paper is to present a performance-improved MPPT controller using a derivative control to a PV panel voltage. The proposed method provides better performances than an existing reported method which uses the derivative control to a reactor current of a dc-dc converter. It is verified that the proposed method obtains quick responses to the rapid change of solar irradiance and dc bus voltage compared to conventional methods.
关键词： dc distribution system,dynamic response,PV system,maximum power point tracking (MPPT),dc-dc converter
更新于2025-09-23 15:23:52
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Adaptive Decentralized Control of Residential Storage in PV-Rich MV-LV Networks
摘要： The rapid adoption of residential-scale photovoltaic (PV) systems in low voltage (LV) networks combined with the falling prices of residential-scale battery energy storage (BES) systems is paving the way for a future in which customers could locally supply most of their energy needs. However, off-the-shelf (OTS) storage systems operate for the sole benefit of the customer (reducing grid imports). This means that charging might not occur during times of high PV generation, resulting in technical issues on LV and medium voltage (MV) networks. This work proposes an adaptive decentralized control strategy for residential-scale BES systems to reduce voltage and thermal issues whilst still benefiting customers. With this strategy, the power charging and discharging rates constantly adapt throughout the day based on clear-sky irradiance, PV generation, demand, and state of charge; significantly reducing reverse power flows and ensuring adequate storage capacity the next morning. A real Australian MV feeder with realistically modelled LV networks is studied using smart meter data. Results demonstrate that the proposed control strategy overcomes the limitations of the OTS BES. It is also shown it can be as effective as an ideal optimization-based approach, being able to manage all technical issues without significantly affecting customers.
关键词： PV Systems,Self-Sufficiency,Distribution Networks,Battery Energy Storage Systems
更新于2025-09-23 15:23:52
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Efficient scheme for passive decoy-state reference-frame-independent quantum key distribution
摘要： Reference-frame-independent quantum key distribution (RFI-QKD) has been demonstrated to be reliable and useful both in theories and experiments, which is intrinsically robust against slowly varying reference frames. In this paper, we propose an efficient scheme of passive decoy-state RFI-QKD based on the parametric down-conversion source, where a beam splitter splits the idler pulses into four local detection events to improve the performance of RFI-QKD systems. In addition, we demonstrate the worst relative rotation of reference frames in our scheme. Simulation results show that our scheme can achieve good performance even at the worst-case scenario.
关键词： Quantum key distribution,Passive decoy-state,Reference-frame-independent
更新于2025-09-23 15:23:52
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[IEEE 2018 IEEE Power & Energy Society General Meeting (PESGM) - Portland, OR, USA (2018.8.5-2018.8.10)] 2018 IEEE Power & Energy Society General Meeting (PESGM) - Comparative Study of Active Power Curtailment Methods of PVs for Preventing Overvoltage on Distribution Feeders
摘要： Overvoltage is one of the major issues on distribution grids with high penetration of photovoltaic (PV) generation. Overvoltage could be prevented through the control of active/reactive power of PVs. However, given the high R/X ratio of low voltage feeders, voltage control by using reactive power would not be as effective as using active power. Therefore, active power curtailment (APC) of PVs, though not desirable, becomes necessary at times to prevent the overvoltage issues. Existing literature is rich in centralized and droop-based methods for APC and/or reactive power control of PVs to prevent overvoltage issues. In this context, this paper revisits the most popular existing methods, and evaluates the performance of droop-based and centralized methods using a typical North American 240 V low voltage feeder with 24 residential homes. In this work, our key findings are: a) droop-based methods provided conservative solutions or did not eliminate the overvoltages completely, b) power flow sensitivity based droop approach led to 13% more curtailment than the centralized approaches, c) centralized approach had 40% less energy curtailed compared with standard droop while no overvoltages were observed, and d) operating PVs at non-unity power factor in centralized approach led to 5% less energy curtailment.
关键词： Inverter,Overvoltage,Photovoltaic,Power Curtailment,Voltage Control,Distribution Grid
更新于2025-09-23 15:23:52
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Hybrid Method for the Synthesis of Isophoric Phase-Shaped Beams
摘要： A novel hybrid approach to the power synthesis of mask-constrained shaped beams by means of concentric-ring isophoric arrays is presented. The basis of this procedure is to use the complex aperture distribution obtained by Elliott–Stern method as a starting point of an innovative algorithm that combines a classical density tapering method with a simulated annealing one. The proposed technique allows to outperform the previous procedures.
关键词： uniform distribution,shaped beams,Density tapering,sparse arrays
更新于2025-09-23 15:23:52
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Li- and Mg-codoped bismuth niobate pyrochlores: Synthesis, structure, electrical properties
摘要： The structure and conductivity of the new Li- and Mg-codoped bismuth niobates Bi1.5Mg1?xLixNb1.5O7?δ (0 ≤ x ≤ 0.50) with the pyrochlore structure have been investigated. The samples were synthesized by the method of organic-inorganic precursors combustion. A structural characterization was performed using 7Li nuclear magnetic resonance (NMR) spectroscopy in combination with the ?tting of X-ray di?raction patterns. The Li+ cations dynamics were studied by temperature-dependent 7Li NMR lineshape analysis. The measurements have shown that the Li+ cations are distributed in one of two possible sublattices in the structure and are not mobile up to 120 °C. According to the results of structural analysis of the Bi1.5Mg1?xLixNb1.5O7?δ (x = 0.25; 0.50) pyrochlores the lithium atoms are distributed in the bismuth sites. The electrical properties were investigated by impedance spectroscopy method in the air, oxygen and “wet” atmospheres in the 25–750 °C temperature range. The activation energy value of dc conductivity is about 1.2–1.3 eV for the all samples and corresponds to the ionic (oxygen) conductivity at T > 400 °C. Electronic (p-type) conductivity was determined at T < 360 °C. 1H MAS NMR data and the results of the comparison of the conductivity of Li- and Mg-codoped bismuth niobates in dry and “wet” atmospheres point to the proton conductivity up to 500 °C. The dielectric permittivity ε′ values increase with lithium content from 86 (x = 0) to 143 (x = 0.5) at the same dielectric loss tanδ = 0.002 (1 MHz, 25 °C), TCC values vary from ?590 to ?530 ppm/°C in the 25–280 °C temperature range.
关键词： Conductivity,Dielectric properties,Pyrochlore,Dopant distribution,NMR spectroscopy,Bismuth niobate
更新于2025-09-23 15:23:52