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Ground-layer Adaptive Optics for the 2.5 m Wide-field and High-resolution Solar Telescope

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Research in Astronomy and Astrophysics 2024年第3期24卷 224-236页

作者： Ying Yang Lan-Qiang Zhang Nan-Fei Yan Jin-Sheng Yang Zhen Li Teng-Fei Song Xue-Jun rao Chang-Hui rao Key Laboratory on Adaptive Optics Chinese Academy of SciencesChengdu 610209China Institute of Optics and Electronics Chinese Academy of SciencesChengdu 610209China School of Electronic Electrical and Communication Engineering of the University of Chinese Academy of SciencesBeijing 100049China university of Chinese Academy of Sciences Beijing 100049China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Key Laboratory of modern A&A Ministry of EducationNanjing 210023China Yunnan Observatories Chinese Academy of SciencesKunming 650216.China

The 2.5 m wide-field and high-resolution solar telescope(WeHoST)is currently under developing for solar *** aims to achieve high-resolution observations over a super-wide field of view(FOV)of5′×5′,and a desired resolution of 0.3″.To meet the scientific requirements of WeHoST,the ground-layer adaptive optics(GLAO)with a specially designed wave front sensing system is as the primary *** introduce the GLAO configuration,particularly the wave front sensing *** analytic method,we simulate the performance of both classical AO and GLAO systems,optimize the wave front sensing system,and evaluate GLAO performance in terms of PSF uniformity and correction improvement across whole *** results indicate that,the classical AO will achieve diffraction-limited resolution;the suggested GLAO configuration will uniformly improve the seeing across the full 5′×5′FOV,reducing the FWHm across the axis FOV to less than0.3″(λ≥705 nm,r0≥11 cm),which is more than two times *** specially designed wave front sensor schedule offers new potential for WeHoST’s GLAO,particularly the multi-FOV GLAO and the flexibility to select the detected *** capabilities will significantly enhance the scientific output of the telescope.

关键词： instrumentation adaptive optics-instrumentation detectors-instrumentation high angular resolution-methods numerical-telescopes-Sun activity

Simulation Study on Constraining Gravitational Wave Propagation Speed by Gravitational Wave and Gamma-ray Burst Joint Observation on Binary Neutron Star mergers

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Research in Astronomy and Astrophysics 2024年第8期24卷 42-51页

作者： Jin-Hui rao Shu-Xu Yi Lian Tao Qing-Wen Tang Department of Physics School of Physics and Materials ScienceNanchang UniversityNanchang 330031China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Theories of modified gravity suggest that the propagation speed of gravitational waves(GW)v_gmay deviate from the speed of light c.A constraint can be placed on the difference between c and v_gwith a simple method that uses the arrival time delay between GW and electromagnetic wave simultaneously emitted from a burst *** simulated the joint observation of GW and short gamma-ray burst signals from binary neutron star merger events in different observation campaigns,involving advanced LIGO(aLIGO)in design sensitivity and Einstein Telescope(ET)joint-detected with Fermi/*** a result,the relative precision of constraint on v_gcan reach~10~(-17)(aLIGO)and~10^(-18)(ET),which are one and two orders of magnitude better than that from GW170817,*** continue to obtain the bound of graviton mass m_g≤7.1(3.2)×10~(-20)eV with aLIGO(ET).Applying the Standard-model Extension test framework,the constraint on v_gallows us to study the Lorentz violation in the nondispersive,nonbirefringent limit of the gravitational *** obtain the constraints of the dimensionless isotropic coefficients S_(00)^(4)at mass dimension d=4,which are-1×10^(-15)

关键词： gravitational waves-(stars)gamma-ray burst general-stars neutron

Phase transition of multi-component(TiZrVNb)C ceramics—Part I:Phase decomposition induced by carbon content

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Journal of Advanced Ceramics 2024年第5期13卷 679-688页

作者： Qingyi Kong rao Zhang Lei Chen Sijia Huo Wenyu Lu Yujin Wang Boxin Wei Yu Zhou Institute for Advanced Ceramics School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150080China Key Laboratory of Advanced Structure‒Function Integrated materials and Green manufacturing Technology Harbin Institute of TechnologyHarbin 150001China School of materials Science and Chemical Engineering Harbin University of Science and TechnologyHarbin 150001China National Key Laboratory of Precision Hot Processing of metals Harbin Institute of TechnologyHarbin 150001China

Phase decomposition can effectively enhance the mechanical properties of carbide ceramics and can overcome the difficulty of enhancing the mechanical properties of single-phase multicomponent carbide *** this work,a series of nonstoichiometric(TiZrVNb)Cx ceramics were prepared by spark plasma sintering(SPS)at different *** effects of the carbon content on the phase composition,microstructure evolution,and mechanical properties were investigated in *** decomposition occurred with decreasing carbon *** different solid solutions of(Ti,V)-rich and Zr-rich phases formed from the decomposition of equimolar single-phase solid solutions,namely,the Zr-poor phase and Zr-rich phase,*** distribution of Nb element is relatively *** semicoherent interfaces between the Zr-poor phase and the Zr-rich phase can harden and strengthen effectively under the synergistic effect of grain *** with phase decomposition structures have apparent advantages compared to single-phase high-entropy *** work provides an important train of thought for the microstructure tailoring and properties optimization of multi-component carbide ceramics.

关键词： multicomponent ceramics nontoichiometry microstructure evolution phase decomposition mechanical properties

Design-build-test of recombinant Bacillus subtilis chassis cell by lifespan engineering for robust bioprocesses

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Synthetic and Systems Biotechnology 2024年第3期9卷 470-480页

作者： Kexin Ren Qiang Wang Jianghua Chen Hengwei Zhang Zhoule Guo meijuan Xu Zhiming rao Xian Zhang Key Laboratory of Industrial Biotechnology of the ministry of Education School of BiotechnologyJiangnan UniversityWuxiJiangsu214122China Yixing Institute of Food and Biotechnology Co. LtdYixing214200China

microbial cell factories utilize renewable raw materials for industrial chemical production,providing a promising path for sustainable *** subtilis is widely used in industry for its food safety properties,but challenges remain in the limitations of microbial *** study proposes a novel strategy based on lifespan engineering to design robust *** chassis cells to supplement traditional metabolic modification strategies that can alleviate cell autolysis,tolerate toxic substrates,and get a higher mass transfer *** modified chassis cells could produce high levels of L-glutaminase,and tolerate hydroquinone to produceα-arbutin *** a 5 L bioreactor,the L-glutaminase enzyme activity of the final strain CRE15TG was increased to 2817.4±21.7 u m L^(-1),about 1.98-fold compared with that of the wild ***α-arbutin yield of strain CRE15A was increased to 134.7 g L^(-1),about 1.34-fold compared with that of the *** our knowledge,both of the products in this study performed the highest yields reported so *** chassis modification strategy described in this study can Improve the utilization efficiency of chassis cells,mitigate the possible adverse effects caused by excessive metabolic modification of engineered strains,and provide a new idea for the future design of microbial cell factories.

关键词： Bacillus subtilis Chassis cell Lifespan engineering Robustness Industrial production

Dimethylamine oxalate manipulating CsPbI_(3) perovskite film crystallization process for high efficiency carbon electrode based perovskite solar cells

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Journal of Energy Chemistry 2024年第6期93卷 221-228,I0006页

作者： Wenran Wang Xin Peng Jianxin Zhang Jiage Lin Rong Huang Guizhi Zhang Huishi Guo Zhenxiao Pan Xinhua Zhong Huashang rao Key Laboratory for Biobased materials and Energy of ministry of Education College of Materials and EnergySouth China Agricultural UniversityGuangzhou 510642GuangdongChina College of Chemistry and Civil Engineering Shaoguan UniversityShaoguan 512005GuangdongChina Guangdong Provincial Key Laboratory of utilization and Conservation of Food and medicinal Resources in Northern Region Shaoguan UniversityShaoguan 512005GuangdongChina

Crystallization process determines the quality of perovskite films and the performances of resultant perovskite solar cells(PSCs).Dimethylamine oxalate has been proven as a multifunctional modulator,and is explored as an efficient additive in manipulating the crystallization process of CsPbI_(3) perovskite *** one hand,oxalate serves as the precipitator that facilitates the nucleation process of *** larger size of intermediate is conductive to the larger size and smaller grain boundaries of resultant *** the other hand,in subsequent annealing process,the phase conversion and growth process of transient perovskite can be decelerated due to the strong interactions of oxalate with both dimethylamine cation(DmA^(+))and Pb^(2+).Due to the optimized crystallization kinetics,the morphology and quality of CsPbI_(3) perovskite films are comprehensively improved with lower defect concentrations,and charge recombination loss is effectively *** from the optimized crystal quality of perovskite films,the carbon electrode-based CsPbI_(3) PSCs exhibit a champion efficiency of 18.48%.This represents one of the highest levels among all hole transport layer-free inorganic perovskite solar cells.

关键词： Solar cells Perovskite CsPbI_(3) Carbon electrodes Oxalate

Improved monarchy Butterfly Optimization Algorithm (ImBO): Intrusion Detection using mapreduce Framework Based Optimized ANu-Net

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Computers, materials & Continua 2023年第6期75卷 5887-5909页

作者： kunda Suresh Babu Yamarthi Narasimha rao School of Computer Science and Engineering VIT-AP UniversityAmaravathi522237Andhra PradeshIndia

The demand for cybersecurity is rising recently due to the rapid improvement of network *** a primary defense mechanism,an intrusion detection system(IDS)was anticipated to adapt and secure com-puting infrastructures from the constantly evolving,sophisticated threat ***,various deep learning methods have been put forth;however,these methods struggle to recognize all forms of assaults,especially infrequent attacks,because of network traffic imbalances and a shortage of aberrant traffic samples for model *** work introduces deep learning(DL)based Attention based Nested u-Net(ANu-Net)for intrusion detection to address these issues and enhance detection *** this IDS model,the first data preprocessing is carried out in three stages:duplication elimi-nation,label transformation,and data *** the features are extracted and selected based on the Improved Flower Pollination Algorithm(IFPA).The Improved monarchy Butterfly Optimization Algorithm(ImBO),a new metaheuristic,is used to modify the hyper-parameters in ANu-Net,effectively increasing the learning rate for spatial-temporal information and resolving the imbalance *** the use of parallel programming,the mapReduce architecture reduces computation complexity while signifi-cantly accelerating *** publicly available data sets were used to evaluate and test the *** investigational outcomes suggest that the proposed technique can more efficiently boost the performances of IDS under the scenario of unbalanced *** proposed method achieves above 98%accuracy and classifies various attacks significantly well compared to other classifiers.

关键词： Intrusion detection system(IDS) attention based nested u-Net

Delamination Testing of AlSi10mg Sandwich Structures with Pyramidal Lattice Truss Core made by Laser Powder Bed Fusion

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Chinese Journal of mechanical Engineering 2021年第6期34卷 51-62页

作者： m.Nuño J.Bühring m.N.rao K.-u.Schröder Institute of Structural mechanics and Lightweight Design RWTH Aachen UniversityWüllnerstraβe 752072 AachenGermany

Sandwich structures possess a high bending stiffness compared to monolithic structures with a similar *** makes them very suitable for lightweight applications,where high stiffness to weight ratios are *** common manufacturing methods of sandwich structures involve adhesive bonding of the core material with the ***,adhesive bonding is prone to delamination,a failure mode that is often difficult to *** paper presents the results of delamination testing of fully additive manufactured(Am)AlSi10mg sandwich structures with pyramidal lattice truss core using Laser Powder Bed Fusion(LPBF).The faces and struts are 0.5 mm thick,while the core is 2 mm *** inclination of the struts is 45°.To characterise the bonding strength,climbing drum peel tests and out-of-plane tensile tests are *** formulas are derived to predict the expected failure loads and *** analytics and tests are supported by finite element(FE)*** the analytic approach,design guidelines to avoid delamination in Am sandwich structures are *** study presents a critical face sheet thickness to strut diameter ratio for which the structure can *** ratio is mainly influenced by the inclination of the *** peel tests resulted in face yielding,which can also be inferred from the analytics and *** out-of-plane tensile tests didn’t damage the structure.

关键词： Additive manufacturing Sandwich Structures Pyramidal Lattice Core

Analysis of vibrational spectra of nano-bio molecules: Application to metalloporphrins

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Chinese Physics B 2013年第9期22卷 225-232页

作者： K Srinivasa rao G Srinivas J.Vijayasekhar V.u.m.rao Y.Srinivas K.Sunil Babu V.Sunndadara Siva Kumar A.Hanumaiah Department of Electronics & Instrumentation Engineering Lakireddy Bali Reddy College of Engineering Department of Physics KL University Research Scholar Department of MathematicsJawaharlal Nehru Technological University Department of Applied mathematics College of Science & TechnologyAndhra University Department of Computer Science GITAM University Department of Physics Miracle Engineering College Department of Electronics & Instrumentation Rajeev Gandhi Memorial Engineering College Department of Physics Lara's Vignan Institute of Technology and Science

In this paper, we have applied the Lie algebraic model to nano-bio molecules to determine the vibrational spectra of different stretching and bending vibrational modes. The determined vibrational energy levels by the Lie algebraic model are compared with the experimental data. The results from the theoretical mode[ are consistent with the experimental data. The vibrational energy levels are clustering in the excited states.

关键词： Lie algebraic model vibrational spectra vibrational modes metalloporphyrins

列车荷载作用下CRTS Ⅲ型板式无砟轨道层间离缝水力特性研究

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中南大学学报（自然科学版） 2024年第7期55卷 2600-2611页

作者：宋力饶佳琪刘冉蒋丽忠余志武中南大学土木工程学院湖南长沙410075 高速铁路建造技术国家工程研究中心湖南长沙410075

在雨水充沛或排水不畅地区,积水会造成无砟轨道层间离缝扩展显著加速。针对含层间离缝的CRTS Ⅲ型板式无砟轨道的水力特性问题,建立列车荷载与水耦合作用下的CRTS Ⅲ型板式无砟轨道-离缝积水双向瞬态流固耦合计算模型,揭示无砟轨道层间... 详细信息

在雨水充沛或排水不畅地区,积水会造成无砟轨道层间离缝扩展显著加速。针对含层间离缝的CRTS Ⅲ型板式无砟轨道的水力特性问题,建立列车荷载与水耦合作用下的CRTS Ⅲ型板式无砟轨道-离缝积水双向瞬态流固耦合计算模型,揭示无砟轨道层间离缝内动水压力和水流速度的分布及其峰值的变化规律,并分析列车轴重、行车速度、离缝形态及积水深度对动水压力和水流速度的影响。研究结果表明:随着列车的趋近与远离,层间离缝内固定点处的动水压力与水流速度呈周期性的正负交替变化;动水压力沿着离缝出口方向逐渐减小,其峰值发生在离缝尖端处,而水流速度沿着离缝出口方向逐渐增大,其峰值发生在离缝出口处;动水压力与水流速度峰值随列车轴重增加而线性增大,轴重每增加1 t,动水压力和水流速度峰值分别增加2.850 kPa、0.085 m/s;动水压力峰值与车速呈二次方增大关系,而在车速小于300 km/h时水流速度峰值与车速基本上呈线性关系,超过该车速后流速增长趋势较之前更大;动水压力、水流速度峰值与离缝开口量呈反比关系;动水压力与水流速度峰值都随着离缝深度和离缝积水深度增加而显著增大,且两者都与离缝深度呈3次多项式增大关系,与离缝积水深度呈2次方增大关系。研究结果可为CRTS Ⅲ型板式无砟轨道在列车荷载与水耦合作用下的层间离缝扩展分析以及养护维修工作提供依据和参考。

关键词： CRTSⅢ型板式无砟轨道层间离缝流固耦合动水压力水流速度

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