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New Antenna Array Beamforming Techniques Based on Hybrid Convolution/Genetic Algorithm for 5G and Beyond Communications

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Computer Modeling in engineering & Sciences 2024年第3期138卷 2749-2767页

作者： Shimaa M.Amer Ashraf A.M.Khalaf Amr H.Hussein Salman A.Alqahtani Mostafa H.Dahshan Hossam M.Kassem Electronics and Communications engineering Department Higher Institute of Engineering and TechnologyKafr ElsheikhEgypt Electronics and Electrical Communications engineering Department Faculty of EngineeringMinia UniversityMiniaEgypt Electronics and Electrical Communications engineering Department Faculty of EngineeringTanta UniversityTantaEgypt Electronics and Electrical Communications engineering Department Faculty of EngineeringHorus University EgyptNew DamiettaEgypt Department of Computer engineering College of computer and Information SciencesKing Saud UniversityRiyadh11543Saudi Arabia school of Computing Mathematics and EngineeringCharles Sturt UniversityBathurstNSW2795Australia

Side lobe level reduction(SLL)of antenna arrays significantly enhances the signal-to-interference ratio and improves the quality of service(QOS)in recent and future wireless communication systems starting from 5G up to ***,it improves the array gain and directivity,increasing the detection range and angular resolution of radar *** study proposes two highly efficient SLL reduction *** techniques are based on the hybridization between either the single convolution or the double convolution algorithms and the genetic algorithm(GA)to develop the Conv/GA andDConv/GA,*** convolution process determines the element’s excitations while the GA optimizes the element *** M elements linear antenna array(LAA),the convolution of the excitation coefficients vector by itself provides a new vector of excitations of length N=(2M−1).This new vector is divided into three different sets of excitations including the odd excitations,even excitations,and middle excitations of lengths M,M−1,andM,*** the same element spacing as the original LAA is used,it is noticed that the odd and even excitations provide a much lower SLL than that of the LAA but with amuch wider half-power beamwidth(HPBW).While the middle excitations give the same HPBWas the original LAA with a relatively higher *** the increased HPBWof the odd and even excitations,the element spacing is optimized using the ***,the synthesized arrays have the same HPBW as the original LAA with a two-fold reduction in the ***,for extreme SLL reduction,the DConv/GA is *** this technique,the same procedure of the aforementioned Conv/GA technique is performed on the resultant even and odd excitation *** provides a relatively wider HPBWthan the original LAA with about quad-fold reduction in the SLL.

关键词： Array synthesis convolution process genetic algorithm(GA) half power beamwidth(HPBW) linear antenna array(LAA) side lobe level(SLL) quality of service(QOS)

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Effect of metal fractions on rice grain metal uptake and biological parameters in mica mines waste contaminated soils

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Journal of Environmental Sciences 2024年第2期136卷 313-324页

作者： Saibal Ghosh Sandip Mondal Jajati Mandal Abhishek Mukherjee Pradip Bhattacharyya Agricultural and Ecological Research Unit Indian Statistical InstituteGiridihJharkhand 815301India school of Science Engineering&EnvironmentUniversity of SalfordManchester M54WTUK

Heavy metals from mica waste not only deteriorate the soil quality but also results in the uptake of metals in the *** present investigation was conducted to evaluate the effects of different fractions of metals on the uptake in rice,soil microbial and biochemical properties in mica waste-contaminated soils of Jharkhand,*** each active mine,soil samples were randomly collected at distances of100 m(zone 3).Sequential metal extraction was used to determine the fractions of different metals(nickel(Ni),cadmium(Cd),chromium(Cr)and lead(Pb))including water-soluble(Ws)and exchangeable metals(Ex),carbonate-bound metals(CBD),Fe/Mn oxide(OXD)bound metals,organically bound metals(ORG),and residues(RS).The Ni,Cr,Cd and Pb in rice grain were 0.83±0.41,0.41±0.19,0.21±0.14 and 0.17±0.08 mg/kg *** the variable importance plot of the random forest(RF)algorithm,the Ws fraction of Ni,Cr and Cd and Ex fraction of Pb was the most important predictor for rice grain metal ***,the partial dependence plots(PDP)give us an insight into the role of the two most important metal fractions on rice grain metal *** microbial and enzyme activity was significantly and negatively correlated with Ws and Ex metal fractions,indicating that water-soluble and exchangeable fractions exert a strong inhibitory effect on the soil microbiological parameters and enzyme activities.

关键词： Metal fractions Microbial parameters Mica waste soil Soil enzymes Rice Random forest

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Theoretical Exploration of Alloying Effects on Stabilities and Mechanical Properties ofγʹPhase in Novel Co–Al–Nb-Base Superalloys

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1238-1248页

作者： Guan-Cheng Gu Zhao-Jing Han Ze-Yu Chen Zhao-Xuan Li Sheng-Bao Xia Zheng-Ning Li Hua Jin Wei-Wei Xu Xing-Jun Liu Shenzhen Research Institute of Xiamen University School of Aerospace EngineeringXiamen UniversityXiamen361005China Institute of Materials Genome and Big Data Harbin Institute of TechnologyShenzhen518055China

The new developedγ/γʹCo–Al–Nb-base alloys show great potentials as high-temperature ***,finding appropriate compositions to improve performance of alloys still poses a great challenge to the development of Co–Al–Nb-base *** by the lack of alloying effects on fundamental properties of criticalγʹphase,we systematically performed a theoretical investigation on the effect of alloying elements TM(TM:Ti,V,Cr,Zr,Mo,Ta,W,Re,and Ru)on phase stabilities and mechanical properties of L1_(2)-typeγʹ(Co,Ni)_(3)(Al,Nb).By analyzing the stability ofγʹphase with respect to its competitive B2 and D0_(19) phases,the results shown that Ti,V,and Cr enhance the L1_(2) stability and widen the L1_(2)–D0_(19) energy barrier,in which V yields the maximum *** analysis of electronic structure indicated that the alternation of valence electrons at fermi level would be the atomic origin for doping TM inγʹ*** calculated results of mechanical properties shown that V and Cr are expected to be optimal dopant for enhancing the strength and the ductility ofγʹ*** addition of Ta is also beneficial for enhancing the strength at the slight expense of ductility ofγʹ*** drawing the mechanical maps,the preferred composition range for the phases with desired properties is roughly demarcated in theory for the multi-addition of V/Cr and V/Ta inγʹ*** findings would be useful for optimizing the performance of novelγ/γʹCo–Al–Nb-base superalloys.

关键词： Co-Al-Nb-base superalloys γ/γʹdual-phase Phase stability Mechanical properties First-principle methods

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Hybrid pedestrian positioning system using wearable inertial sensors and ultrasonic ranging

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Defence Technology（防务技术） 2024年第3期33卷 327-338页

作者： Lin Qi Yu Liu Chuanshun Gao Tao Feng Yue Yu school of Communication and Information engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China Department of Land Surveying and Geo-Informatics The Hong Kong Polytechnic UniversityHong Kong 999077China

Pedestrian positioning system(PPS)using wearable inertial sensors has wide applications towards various emerging fields such as smart healthcare,emergency rescue,soldier positioning,*** performance of traditional PPS is limited by the cumulative error of inertial sensors,complex motion modes of pedestrians,and the low robustness of the multi-sensor collaboration *** paper presents a hybrid pedestrian positioning system using the combination of wearable inertial sensors and ultrasonic ranging(H-PPS).A robust two nodes integration structure is developed to adaptively combine the motion data acquired from the single waist-mounted and foot-mounted node,and enhanced by a novel ellipsoid constraint *** addition,a deep-learning-based walking speed estimator is proposed by considering all the motion features provided by different nodes,which effectively reduces the cumulative error originating from inertial ***,a comprehensive data and model dual-driven model is presented to effectively combine the motion data provided by different sensor nodes and walking speed estimator,and multi-level constraints are extracted to further improve the performance of the overall *** results indicate that the proposed H-PPS significantly improves the performance of the single PPS and outperforms existing algorithms in accuracy index under complex indoor scenarios.

关键词： Pedestrian positioning system Wearable inertial sensors Ultrasonic ranging Deep-learning Data and model dual-driven

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Burst-mode pulse generation in passively mode-locked all-fiber green/orange lasers at 543 nm and 602 nm

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Photonics Research 2024年第6期12卷 1231-1238页

作者： QIUJUN RUAN JINHAI ZOU CHUNNA FENG TINGTING CHEN HANG WANG ZHIPENG DONG ZHENGQIAN LUO Fujian Key Laboratory of Ultrafast Laser Technology and Applications School of Electronic Science and EngineeringXiamen UniversityXiamen 361005China Shenzhen Research Institution of Xiamen University Shenzhen 518000China

We report on the experimental realization of,to the best of our knowledge,the first green and orange passively mode-locked all-fiber *** mode-locking in the burst-pulse status is achieved at the wavelengths of 543.3 nm and 602.5 *** figure-9 cavity comprises the fiber end-facet mirror,gain fiber(Ho^(3+):ZBLAN fiber or Pr^(3+)/Yb^(3+):ZBLAN fiber),and fiber loop mirror(FLM).The FLM with long 460 HP fiber is not only used as an output mirror,but also acts as a nonlinear optical loop mirror for initiating visible-wavelength *** green/orange mode-locked fiber lasers with the fundamental repetition rates of 3.779/5.662 MHz produce long bursts containing ultrashort pulses with the 0.85/0.76 GHz intra-burst repetition rates,*** ultrashort intra-burst pulses stem from the dissipative four-wave-mixing effect in the highly nonlinear FLM as well as the intracavity Fabry–Perot *** bursts of 22.2/11.6 ns with ultrashort pulses of 87/62 ps are obtained in our *** visible-wavelength passively mode-locked lasers in an all-fiber configuration and burst-mode would represent an important step towards miniaturized ultrafast fiber lasers and may contribute to the applications in ablation-cooling micromachining,biomedicine imaging,and scientific research.

关键词： fiber passive pulse

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Aβ-Aggregation-Generated Blue Autofluorescence Illuminates Senile Plaques as well as Complex Blood and Vascular Pathologies in Alzheimer’s Disease

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Neuroscience Bulletin 2024年第8期40卷 1115-1126页

作者： Hualin Fu Jilong Li Chunlei Zhang Peng Du Guo Gao Qiqi Ge Xinping Guan Daxiang Cui Institute of Nano Biomedicine and engineering School of Sensing Science and EngineeringSchool of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Institute of Marine Equipment Shanghai Jiao Tong UniversityShanghai 200240China National Center for Translational Medicine Shanghai Jiao Tong UniversityShanghai 200240China Department of Colorectal Surgery School of MedicineXinhua HospitalShanghai Jiao Tong UniversityShanghai 200092China Department of Automation Shanghai Jiao Tong UniversityShanghai 200240China The Key Laboratory of System Control and Information Processing Ministry of EducationShanghai 200240China

Senile plaque blue autofluorescence was discovered around 40 years ago,however,its impact on Alzheimer’s disease(AD)pathology has not been fully *** analyzed senile plaques with immunohistochemistry and fluorescence imaging on AD brain sections and also Aβ aggregation in *** DAPI or Hoechst staining,the nuclear blue fluorescence could only be correctly assigned after subtracting the blue plaque *** flower-like structures wrapping dense-core blue fluorescence formed by cathepsin D staining could not be considered central-nucleated neurons with defective lysosomes since there was no nuclear staining in the plaque core when the blue autofluorescence was *** Aβ self-oligomers and Aβ/hemoglobin heterocomplexes generated blue *** Aβ amyloid blue autofluorescence not only labels senile plaques but also illustrates red cell aggregation,hemolysis,cerebral amyloid angiopathy,vascular plaques,vascular adhesions,and *** summary,we conclude that Aβ-aggregation-generated blue autofluorescence is an excellent multi-amyloidosis marker in Alzheimer’s disease.

关键词： Senile plaque Blue autofluorescence Aβ Amyloid aggregation Hemoglobin Cathepsin D.Microaneurysm Alzheimer's disease

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New Algebraic Attacks on Grendel with the Strategy of Bypassing SPN Steps

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Chinese Journal of Electronics 2024年第3期33卷 635-644页

作者： Wenxiao QIAO Siwei SUN Lei HU State Key Laboratory of Information Security Institute of Information Engineering Chinese Academy of Sciences school of Cyber Security University of Chinese Academy of Sciences school of Cryptology University of Chinese Academy of Sciences State Key Laboratory of Cryptology

The rapid development of modern cryptographic applications such as zero-knowledge,secure multiparty computation,fully homomorphic encryption has motivated the design of new so-called arithmetization-oriented symmetric *** designing ciphers in this domain is relatively new and not well-understood,the security of these new ciphers remains to be completely *** this paper,we revisit the security analysis of arithmetizat ionoriented cipher *** uses the Legendre symbol as a component,which is tailored specifically for the use in zero-knowledge and efficiently-varifiable proof *** FSE 2022,the first preimage attack on some original full GrendelHash instances was *** a countermeasure,the designer adds this attack into the security analysis and updates the formula to derive the secure number of *** our work,we present new algebraic attacks on *** the preimage attack,we can reduce the complexity or attack one more round than previous attacks for some *** addition,we present the first collision attack on some round-reduced instances by solving the constrained input/constrained output problem for the underlying permutations.

关键词： Ciphers Symbols Multi-party computation Complexity theory Homomorphic encryption

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Enhanced gas production and CO_(2) storage in hydrate-bearing sediments via pre-depressurization and rapid CO_(2) injection

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Chinese Journal of Chemical engineering 2024年第3期67卷 126-134页

作者： Hongnan Chen Yifei Sun Bojian Cao Minglong Wang Ming Wang Jinrong Zhong Changyu Sun Guangjin Chen State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China school of Chemistry and Chemical engineering Changsha University of Science&TechnologyChangsha 410114China

Carbon emission reduction and clean energy development are urgent demands for mankind in the coming *** an efficient CO_(2) storage method can significantly reduce CO_(2) emissions in the short *** this study,we attempted to construct sediment samples with different residual CH_(4) hydrate amounts and reservoir conditions,and then investigate the potentials of both CO_(2) storage and enhanced CH_(4) recovery in depleted gas hydrate deposits in the permafrost and ocean zones,*** results demonstrate that CO_(2) hydrate formation rate can be significantly improved due to the presence of residual hydrate seeds;However,excessive residual hydrates in turn lead to the decrease in CO_(2) storage *** by the T-P conditions of the reservoir,the storage amount of liquid CO_(2) can reach 8 times that of gaseous CO_(2),and CO_(2) stored in hydrate form reaches 2-4 ***,we noticed two other advantages of this *** is that CO_(2) injection can enhance CH_(4) recovery rate and increases CH_(4) recovery by 10%-20%.The second is that hydrate saturation in the reservoir can be restored to 20%-40%,which means that the solid volume of the reservoir avoids serious ***,this is crucial for protecting the goaf *** summary,this approach is greatly promising for high-efficient CO_(2) storage and safe exploitation of gas hydrate.

关键词： Hydrate Depressurization CO_(2) storage CH_(4) production Reservoir remediation

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Plasma density enhancement in radio-frequency hollow electrode discharge

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Plasma Science and Technology 2024年第4期26卷 44-51页

作者：贺柳良何锋欧阳吉庭 College of Science Beijing University of Civil Engineering and ArchitectureBeijing 102616People’s Republic of China school of Physics Beijing Institute of TechnologyBeijing 100081People’s Republic of China

The plasma density enhancement outside hollow electrodes in capacitively coupled radio-frequency(RF) discharges is investigated by a two-dimensional(2D) particle-in-cell/Monte-Carlo collision(PIC/MCC) model. Results show that plasma exists inside the cavity when the sheath inside the hollow electrode hole is fully collapsed, which is an essential condition for the plasma density enhancement outside hollow electrodes. In addition, the existence of the electron density peak at the orifice is generated via the hollow cathode effect(HCE), which plays an important role in the density enhancement. It is also found that the radial width of bulk plasma at the orifice affects the magnitude of the density enhancement, and narrow radial plasma bulk width at the orifice is not beneficial to obtain high-density plasma outside hollow *** electron density at the orifice, combined with larger radial plasma bulk width at the orifice,causes higher electron density outside hollow electrodes. The results also imply that the HCE strength inside the cavity cannot be determined by the magnitude of the electron density outside hollow electrodes.

关键词： RF capacitively coupled plasma sources plasma density enhancement hollow cathodeeffect hollow electrode

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Approaching high oxygen evolution reaction performance by synergetic dual-ion leaching

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Nano Research 2024年第9期17卷 7975-7983页

作者： Hancheng Ma Yao Ding Jianqi Li Wei Peng Liqiang Mai school of Materials Science and engineering Wuhan University of TechnologyWuhan 430070China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Self-reconstruction of catalysts during oxygen evolution reaction(OER)is crucial for the development of energy conversion ***,the relationship between the specific atomic structure of pre-catalysts and their electrocatalytic behavior after reconstruction via dual-ion leaching has not been extensively *** this work,we design a highly effective non-noble metal OER catalyst with heterointerface through continuous self-reconstruction of Co_(2)(OH)_(3)Cl@NiMoO_(4)as pre-catalyst by a straightforward dual-ion(***_(4)^(2-)and Cl^(-))***-situ Raman and in-situ Fourier transform infrared(FT-IR)spectroscopy have precisely identified the progressive phase transformation of the pre-catalyst during self-reconstruction,which results in a stable heterojunction of CoOOH and NiOOH(CoOOH@NiOOH).Further calculations based on density functional theory(DFT)of CoOOH@NiOOH evident that more electrons will be aggregated in the Fermi level of ***,Gibbs free energy(ΔG)for different OER steps of CoOOH@NiOOH exhibit lower energy costs of all intermediates,implying the well catalytic ***,the catalyst derived from dual-ion leaching displays outstanding OER performance,characterized by an overpotential of 275 mV at a current density of 10 mA·cm^(-2)and exceptional stability over 12 h *** work successfully paves a way of finding high-performance OER catalysts based on non-noble metal through dual-ion leaching during self-reconstruction.

关键词： dual-ion leaching oxygen evolution reaction chemical reconstruction NiMoO_(4) Co_(2)(OH)_(3)Cl

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