Future Sixth-Generation (6G) mobile communication networks extremely require the global connectivity and the ground Base Stations (BSs) are difficult to develop in some specific areas,such as mountainous ***,the aeria...
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Future Sixth-Generation (6G) mobile communication networks extremely require the global connectivity and the ground Base Stations (BSs) are difficult to develop in some specific areas,such as mountainous ***,the aerial networks are the key framework for the future communications,in which the aerial vehicle could act as the access ***,Mobile Edge Computing (MEC) is also essential to enhance the data processing capabilities of aerial *** this paper,we study a comprehensive communication-computation resource management problem for jointly optimizing user pairing,power and time allocation in the MEC aided Cognitive radio (Cr) aerial networks,namely Cr-MEC aerial ***,this multilevel optimization problem could be decomposed into the user pairing and power allocation as well as time allocation *** the conceived Cr-MEC aerial networks,we propose a User Pairing and Computation Offloading Management Algorithm (UPCOMA) based on three-sided matching theory,aiming to minimize the system’s energy *** the first step of UPCOMA,multiple Primary Users (PUs) and Cognitive Users (CUs) on the ground negotiate to each other with the suitable power allocation coefficients and construct the stable user ***,the stable user pairs would match to a high altitude platform who act as the base station,which is for appropriately allocating Transmission Time Slots (TSs) at the second step of ***,a hybrid offloading mode is proposed in our conceived networks in order to support ground users to offload their tasks adaptively according to their individual ***,the simulation results reveal that the relative performance of UPCOMA is close to that of the Brute-Force Search Algorithm (BFSA) with low ***,the hybrid offloading mode with less energy consumption supports much more ground user pairs to offload tasks compared to the binary mode.
Previous studies of the transition metal chalcogenide Ta2NiSe5 has identified two phase transitions occurring between 0-10 GPa, involving the excitonic insulator-to-semiconductor transition at 1 GPa and the semiconduc...
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Previous studies of the transition metal chalcogenide Ta2NiSe5 has identified two phase transitions occurring between 0-10 GPa, involving the excitonic insulator-to-semiconductor transition at 1 GPa and the semiconductor-to-semimetal transition at 3 GPa. However, there is still a lack of in-depth research on the changes in its physical properties changes above 10 GPa. In this study, Ta2NiSe5 were investigated under high-pressure conditions using high-pressure x-ray diffraction and high-pressure x-ray absorption experiments. during the experimental process, a novel phase transition from the semimetal to the metal phase was observed between 10-60 GPa, specifically between 10-14 GPa, and the structure of the new phase was determined to be P2(1)/m through first-principles calculations. This transition mechanism is attributed to the sliding of the weakly coupled layers of Ta2NiSe5 within the a-c plane, leading to changes in the crystal lattice constants and symmetry. This research fills a gap in the understanding of Ta2NiSe5 's crystal structure under high pressure and contributes to the broader field of transition metal chalcogenides.
The existing physical layer security schemes,which are based on the key generation model and the wire-tap channel model,achieve security by utilizing channel reciprocity entropy and noise entropy,*** contrast,we propo...
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The existing physical layer security schemes,which are based on the key generation model and the wire-tap channel model,achieve security by utilizing channel reciprocity entropy and noise entropy,*** contrast,we propose a novel secure transmission framework that combines noise entropy with reciprocity entropy,achieved by inserting reciprocity entropy into the frozen bits of polar *** that in real-world scenarios,when eavesdroppers employ polynomial-time attacks,the bit errorrate(BEr)increases due to the introduction of computational *** achieve indistinguishability security,we convert the practical physical layer security metric,BEr,into the average min-entropy,a widely accepted concept in *** simulation results demonstrate that the eavesdropper’s BEr can be significantly increased without compromising the communication performance of the legitimate *** concrete parameters we selected,when compared to the joint scheme of physical layerkey generation and one time pad,the modular semantically-secure scheme based on the wire-tap channel model,and the simple channel entropy combination scheme,our scheme achieves a message rate approximately 1.2 times,3.8 times,and 1.4 times better,*** testing validates the feasibility of our scheme.
To address the mooring issues of floating photovoltaic systems in areas with large tidal variations,three mooring schemes were designed and compared in this paper:anchor chain,anchor chain with added weights,and ancho...
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To address the mooring issues of floating photovoltaic systems in areas with large tidal variations,three mooring schemes were designed and compared in this paper:anchor chain,anchor chain with added weights,and anchor chain with *** model was established via the numerical simulation tool Orcaflex,which considers the combined effects of wind,waves,and currents.A time-domain coupleddynamic analysis was conducted on the performance of the three mooring schemes under various tidal conditions to determine the mooring cable tension and platform motion ***,the mooring system with an anchor chain and Superflex was optimized,with a focus on analyzing the effects of the Superflex length,the diameter of the anchor chains,and the mooring *** mooring system with the anchor chain and Superflex exhibits more controllable and stable mooring performance in areas with large tidal variations,so that it more effectively maintains the required mooring tension *** findings not only provide a reference for the feasibility and optimization design of photovoltaic systems in areas with large tidal variations but also offer valuable experience for the sustainable application of clean energy under specific environmental conditions.
Question Generation(QG)is the task of generating questions according to the given *** of the existing methods are based on recurrent Neural Networks(rNNs)for generating questions with passage-level input for providing...
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Question Generation(QG)is the task of generating questions according to the given *** of the existing methods are based on recurrent Neural Networks(rNNs)for generating questions with passage-level input for providing more details,which seriously suffer from such problems as gradient vanishing and ineffective information *** fact,reasonably extracting useful information from a given context is more in line with our actual needs during questioning especially in the education *** that end,in this paper,we propose a novel Hierarchical Answer-Aware and Context-Aware Network(HACAN)to construct a high-quality passage representation and judge the balance between the sentences and the whole ***,a Hierarchical Passage Encoder(HPE)is proposed to construct an answer-aware and context-aware passage representation,with a strategy of utilizing multi-hop ***,we draw inspiration from the actual human questioning process anddesign a Hierarchical Passage-aware decoder(HPd)which determines when to utilize the passage *** conduct extensive experiments on the SQuAddataset,where the results verify the effectivenesss of our model in comparison with several baselines.
For combined sensible-latent heat storage system(CSLHS)(termed as the hybrid configuration),macro encapsulation can effectively solve the leakage problem of ***,due to the poor thermal conductivity of PCMs,the chargin...
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For combined sensible-latent heat storage system(CSLHS)(termed as the hybrid configuration),macro encapsulation can effectively solve the leakage problem of ***,due to the poor thermal conductivity of PCMs,the charging performance of the hybrid configuration slightly increases compared to the solid structure(with only sensible materials).Meanwhile,the natural convection in the PCMs zone could improve the charging ***,how to improve natural convection intensity is a key issue for the CSLHS by macro *** is found that adding fins can significantly enhance natural convection and accelerate the melting of *** this paper,we proposed the hybrid configuration with fins built-in by macro encapsulation,and analyzed its charging performance with different fin structural parameters in the PCM zone by CFd *** the case,the sensible heat storage material is high-temperature concrete and the PCM is a low-melting-point mixed molten *** analyzed the effects of fin number,fin length and fin thickness on the charging performance of the hybrid configuration *** the result,the charging performance increases with the fin number,but the increase rate gradually *** the fin number is 6,the charging performance increases by 20.18%compared to the situation without *** charging performance increases gradually with the fin *** with the hybrid configuration without fin,for each 10 mm increase in fin length,its charging performances increase by 4.09%,5.26%,7.02%,8.77%,11.70%,and 15.79%,*** from number and length of fins,the effect of thickness on the charging performance is very *** the fin thickness increased from 1 mm to 4 mm,the charging performance only increased by 2.3%.It indicates that the main reason for the improving the charging performance is to increase the natural convection intensity by dividing the PCM zone through *** results show that the charging performance
High-quality optical components have been widely used in various applications;thus,extremely high beam quality is ***,surface roughness is a key indicator of the surface *** this study,the angulardistribution of ligh...
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High-quality optical components have been widely used in various applications;thus,extremely high beam quality is ***,surface roughness is a key indicator of the surface *** this study,the angulardistribution of light scattering field intensity was obtained for surfaces having different roughness profiles based on the finite difference time domain(FdTd)method,and the results were compared with those obtained using the generalized Harvey-Shack(GHS)*** was shown that the FdTd approach can be used for an accurate simulation of the scattered field of a rough surface,and the superposition of results obtained from many surfaces that have the same roughness level was in good agreement with the result given by the analytic GHS model.A light scattering matrix(LSM)method was proposed based on the FdTd simulation results that could obtain rich surface roughness *** classification effect of LSM was compared with that of the single-incidence scattering distribution(SISd)based on a resNet-50 deep learning *** classification accuracy of the model trained with the LSM dataset was obtained as 95.74%,which was 23.40%higher than that trained using the SISd ***,the effects of different noise types and filtering methods on the classification performance were analyzed,and the LSM was also shown to improve the robustness and generalizability of the trained surface roughness ***,the proposed LSM method has important implications for improving the data acquisition scheme of current light scattering measurement systems,and it also has the potential to be used fordetection and characterization of surface defects of optical components.
2,2 ',4,4 ',6,6 '-hexanitrostilbene (HNS) is a heat-resistant, low-sensitivity energetic material with widespread applications in pliable linear-shaped charges, high-temperature-resistant oil well perforat...
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2,2 ',4,4 ',6,6 '-hexanitrostilbene (HNS) is a heat-resistant, low-sensitivity energetic material with widespread applications in pliable linear-shaped charges, high-temperature-resistant oil well perforating charges, androcket propellants. However, the presence of highly toxic and mutagenic nitroaromatic compounds in HNS wastewater necessitates efficient and accurate detection methods. Unfortunately, the existing analytical methods for HNS detection are outdated and incompatible with modern equipment. This limits their application due to issues with detection range, accuracy, and cost. To address this gap, an improved method was developed using an Ultimate 3000 UHPLC system with methanol and water as the mobile phase and UV-Vis detection at 271 and 226 nm wavelengths. The results indicate that the optimal detection conditions are achieved with a methanol-to-waterratio of 70:30 and a flow rate of 0.5 mL/min, providing high accuracy and efficiency. Compared to traditional methods, this approach reduced the detection time by nearly 70%, with the shortest analysis time ranging from 6 to 6.5 min, significantly lowering the cost of HNS detection. The methoddemonstrated excellent linearity (r-2 > 0.9999) and high sensitivity within the concentration range of 0.50-150.00 mg/L, with precise andreliable results. This work provides both theoretical insights and experimental validation for the detection and analysis of HNS in wastewater.
The spin superconductor state is the spin-polarized triplet exciton condensate,which can be viewed as a counterpart of the charge superconductor *** an analogy of the charge Josephson effect,the spin Josephson effect ...
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The spin superconductor state is the spin-polarized triplet exciton condensate,which can be viewed as a counterpart of the charge superconductor *** an analogy of the charge Josephson effect,the spin Josephson effect can be generated in the spin superconductor/normal metal/spin superconductor *** we study the spin supercurrent in the Josephson junctions consisting of two spin superconductors with noncollinear spin *** the Josephson junctions with out-of-plane spin polarizations,the possibleπ-state spin supercurrent appears due to the Fermi momentum-splitting Andreev-like reflections at the normal metal/spin superconductor *** the Josephson junctions with in-plane spin polarizations,the anomalous spin supercurrent appears and is driven by the misorientation angle of the in-plane *** symmetry analysis shows that the appearance of the anomalous spin Josephson current is possible when the combined symmetry of the spin rotation and the time reversal is broken.
A virtual cosmetics try-on system provides a realistic try-on experience for consumers and helps them efficiently choose suitable *** this article,we propose a real-time augmentedreality virtual cosmetics try-on syst...
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A virtual cosmetics try-on system provides a realistic try-on experience for consumers and helps them efficiently choose suitable *** this article,we propose a real-time augmentedreality virtual cosmetics try-on system for smartphones(ArCosmetics),taking speed,accuracy,and stability into consideration at each step to ensure a better user experience.A novel and very fast face tracking method utilizes the face detection box and the average position of facial landmarks to estimate the faces in continuous frames.A dynamic weight Wing loss is introduced to assign a dynamic weight to every landmark by the estimated errorduring *** balances the attention between small,medium,and large range error and thus increases the accuracy and *** also designed a weighted average method to utilize the information of the adjacent frame for landmark refinement,guaranteeing the stability of the generated *** experiments conducted on a large 106-point facial landmark dataset and the 300-VW dataset demonstrate the superior performance of the proposed method compared to other state-of-the-art *** also conducted user satisfaction studies further to verify the efficiency and effectiveness of our ArCosmetics system.
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