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Measuring the anisotropies in astrophysical and cosmological gravitational-wave backgrounds with Taiji and LISA networks

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Science China(physics,Mechanics & Astronomy) 2024年

作者： Zhi-Chao Zhao Sai Wang Department of Applied physics College of Science China Agricultural University Theoretical physics Division Institute of High Energy Physics Chinese Academy of Sciences

We investigate the capabilities of space-based gravitational-wave detector networks, specifically Taiji and LISA, to measure the anisotropies in stochastic gravitational-wave background(SGWB), which are characterized by the angular power spectrum. We find that a detector network can improve the measurement precision of anisotropies by at most fourteen orders of magnitude,depending on the angular multipoles. By doing so, we can enhance our understanding of the physical origins of SGWB, both in astrophysical and cosmological contexts. We assess the prospects of the detector networks for measuring the parameters of angular power spectrum. We further find an inevitable effect of cosmic variance, which can be suppressed by a better angular resolution, strengthening the importance of configuring detector networks. Our findings also suggest a potential detection of the kinematic dipole due to Doppler boosting of SGWB.

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Flavone improves liver damage in nicotine-exposed rats via the Nrf2/HO-1 pathway

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Asian Pacific Journal of Tropical Biomedicine 2024年第8期14卷 341-349页

作者： Nora A.Elsayed Fatma SM Moawed Esraa SA Ahmed Ahmed Hammad Omayma AR Abo-Zaid Biochemistry and Molecular Biology Department Faculty of Vet.Med.Benha UniversityBenha cityEgypt Health Radiation Research National Center for Radiation Research and TechnologyEgyptian Atomic Energy AuthorityCairoEgypt Radiation Biology Department National Center for Radiation Research and TechnologyEgyptian Atomic Energy AuthorityCairoEgypt

Objective:To assess the hepatoprotective effects of flavone on nicotine-induced liver ***:Thirty-six rats were allocated into six groups:the control group,the nicotine group,the flavone alone groups(10 and 25 mg/kg/body weight),and the nicotine groups treated with flavone(10 and 25 mg/kg/body weight).Liver function,oxidative stress,Nrf2 pathway(HO-1,Nrf2,and Keap-1),and inflammatory markers(IL-17,TNF-α,and NF-κB)were ***,a histopathological examination of liver tissues was ***:Nicotine increased liver damage,inflammation,and oxidative ***,flavone suppressed nicotine-induced liver enzymes,oxidative stress,and inflammation,as manifested by increased antioxidants and decreased malondialdehyde level,liver enzymatic activities,and inflammatory ***(10 and 25 mg/kg/body weight)also reduced the level of Keap-1 and increased HO-1 and Nrf2 levels in the liver of nicotine-exposed ***:Flavone has hepatoprotective properties and may slow the progression of liver injury by reducing oxidative stress,liver enzymes,and inflammation possibly via the Nrf2 pathway.

关键词： Flavone Nicotine Liver Nrf2 HO-1 NF-κB

Tunable magneto-Seebeck effect in Co_(2)FeSi/MgO/Co_(2)FeSi heterostructure via optimized interfacial engineering

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Science China(physics,Mechanics & Astronomy) 2024年第3期67卷 128-135页

作者： Jingyu Li Xianbiao Shi Yurong Jin Le Ma Liuming Wei Chi Zhang Hang Li Peng-Fei Liu International Joint Research Laboratory of New energy Materials and Devices of Henan Province School of Physics and ElectronicsHenan UniversityKaifeng 475004China Institute of high energy physics Chinese Academy of SciencesBeijing 100049China Spallation Neutron Source Science Center Dongguan 523803China Defence Industry Secrecy Examination and Certification Center Beijing 100089China School of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China Department of network Security Henan Police CollegeZhengzhou 450046China College of Electrical Engineering Henan University of TechnologyZhengzhou 450001China

Enhancing the tunneling magneto-Seebeck(TMS) ratio and uncovering its underlying mechanism are greatly demanded in spin *** magnitude and sign of the TMS effect depend on the type of atom and the stacking order of atoms at the ***,we demonstrate that TMS ratios can be effectively manipulated by altering heterogonous or homogeneous interface through decoration on the CoFeSi(001) surface inserted on the MgO insulating *** maximum TMS ratio of pure Co_(2)/O termination is 4565% at 800 ***,the TMS ratio of the FeSi/O termination has two peak values,of which the maximum could reach up to-3290% at 650 *** comparing two different atom arrangements at the interface,we reveal that the sign and symbol of the TMS ratio can be controlled by the temperature and different atomic configurations at the Co_(2)FeSi/MgO ***,the spin-Seebeck coefficient up to ~150 μV/K is also possible when we select suitable terminations and *** findings will provide useful insights into how to control the sign and symbol of the TMS ratio and accordingly stimulate the development field of magneto-thermoelectric power and spin caloritronic devices based on the magneto-Seebeck effect in Heusler-based metallic multilayers.

关键词： magneto-Seebeck effect interface spintronics electronic structure spin-Seebeck effect

Design Research of a Novel Aftercool-Humidifier Concept for Humid Air Turbine Cycle

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Journal of Thermal Science 2024年第3期33卷 951-969页

作者： ZHANG Junzheng XU Zhen School of energy and Power Engineering Shandong UniversityJi’nan250061China Shandong Engineering Laboratory for high-efficiency energy Conservation and energy Storage Technology&Equipment Shandong UniversityJi’nan250061China

Humid air turbine cycle(HAT)has potential of electrical efficiencies comparable to combined cycle,with lower investment cost and NO_(x) *** typical heat exchanger network of HAT consists of intercooler(if there is),aftercooler,recuperator,economizer and humidifier,which brings higher efficiency but makes the system more *** simplify HAT layout,a novel humidifier concept is proposed by integrating the aftercooler into traditional counter-current *** on this concept,a one-dimensional model including pressure drop and exergy calculation is established to distinguish the thermodynamic and hydrodynamic characteristics,and then the structural parameters,such as the number of rows and columns,tube diameter,pitch and type for a micro HAT are *** results show that the aftercool-humidifier plays the same role as original aftercooler and humidifier,and can match the in-tube air,out-tube air and water stream well with lower *** the case of micro HAT cycle,the volume of heat and mass transfer area can be reduced by 47%compared with traditional *** major thermal resistance occurred in the convection heat transfer process inside the tube;however,using enhanced tube cannot effectively improve the compactness of device.

关键词： humid air turbine cycle humidifier thermodynamic analysis one-dimensional model

Research on intelligent search-and-secure technology in accelerator hazardous areas based on machine vision

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Nuclear Science and Techniques 2024年第4期35卷 96-107页

作者： Ying-Lin Ma Yao Wang Hong-Mei Shi Hui-Jie Zhang School of Traffic and Transportation Beijing Jiaotong UniversityBeijing 100044China School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Institute of high energy physics Chinese Academy of SciencesBeijing 100049China

Prompt radiation emitted during accelerator operation poses a significant health risk,necessitating a thorough search and securing of hazardous areas prior to ***,manual sweep methods are ***,the limitations of manual sweeps have become increasingly evident with the implementation of large-scale *** leveraging advancements in machine vision technology,the automatic identification of stranded personnel in controlled areas through camera imagery presents a viable solution for efficient search and *** the criticality of personal safety for stranded individuals,search and security processes must be sufficiently *** ensure comprehensive coverage,180°camera groups were strategically positioned on both sides of the accelerator tunnel to eliminate blind spots within the monitoring *** YOLOV8 network model was modified to enable the detection of small targets,such as hands and feet,as well as larger targets formed by individuals near the ***,the system incorporates a pedestrian recognition model that detects human body parts,and an information fusion strategy is used to integrate the detected head,hands,and feet with the identified pedestrians as a cohesive *** strategy enhanced the capability of the model to identify pedestrians obstructed by equipment,resulting in a notable improvement in the recall ***,recall rates of 0.915 and 0.82were obtained for Datasets 1 and 2,*** there was a slight decrease in accuracy,it aligned with the intended purpose of the search-and-secure software *** tests conducted within an accelerator tunnel demonstrated the effectiveness of this approach in achieving reliable recognition outcomes.

关键词： Search and secure Machine vision Camera Human body parts recognition Particle accelerator Hazardous area

Domain wall network:A dual solution for gravitational waves and Hubble tension?

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Science China(physics,Mechanics & Astronomy) 2024年第11期67卷 39-46页

作者： Ligong Bian Shuailiang Ge Changhong Li Jing Shu Junchao Zong Department of physics and Chongqing Key Laboratory for Strongly Coupled physics Chongqing UniversityChongqing 401331China Center for high energy physics Peking UniversityBeijing 100871China School of physics and State Key Laboratory of Nuclear physics and Technology Peking UniversityBeijing 100871China Department of Astronomy Key Laboratory of Astroparticle Physics of Yunnan ProvinceSchool of Physics and AstronomyYunnan UniversityKunming 650091China Beijing Laser Acceleration Innovation Center Beijing 101400China Department of physics Nanjing UniversityNanjing 210093China CAS Key Laboratory of Theoretical physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China

We explore the possibility that domain wall networks generate the stochastic gravitational wave background(SGWB) observed as a strong common power-law process in the Data Release-2 of Parkes Pulsar Timing Array. We find that a broad range of parameters, specifically wall tension around σ_(DW)^(29-414 TeV)^(3) and wall-decay temperature within T_(d) ~ 20-257 MeV, can explain this phenomenon at a 68% credible level. Meanwhile, the same parameters could ease the Hubble tension if particles from these domain wall networks decay into dark radiation. We establish a direct analytical relationship, ΩGW(f_(p), T_(0))h^(2)~ Ω_(rad)h^(2)(Ω_νΩN_(eff))^(2),to illustrate this coincidence, underlining its importance in the underlying physics and potential applicability to a wider range of models and data. Conversely, if the common power-law process is not attributed to domain wall networks, our findings impose tight limits on the wall tension and decay temperature.

关键词： domain wall gravitational waves Hubble tension

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Linear OPF-based Robust Dynamic Operating Envelopes with Uncertainties in Unbalanced Distribution networks

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Journal of Modern Power Systems and Clean energy 2024年第4期12卷 1320-1326页

作者： Bin Liu Julio H.Braslavsky Nariman Mahdavi energy Centre Commonwealth Scientific and Industrial Research Organisation(CSIRO)Newcastle 2300Australia the network Planning Division TransgridSydney 2000Australia the energy Systems Program Energy CentreCommonwealth Scientific and Industrial Research Organisation(CSIRO)Newcastle 2300Australia

Dynamic operating envelopes(DOEs),as key enablers to facilitate distributed energy resource(DER)integration,have attracted increasing attention in the past ***,uncertainties,which may come from load forecasting errors or inaccurate network parameters,have been rarely discussed in DOE calculation,leading to compromised quality of the hosting capacity allocation *** letter studies how to calculate DOEs that are immune to such uncertainties based on a linearised unbalanced three-phase optimal power flow(UTOPF)*** uncertain parameters constrained by norm balls,formulations for calculating robust DOEs(RDOEs)are presented along with discussions on their *** cases,including a 2-bus illustrative network and a representative Australian network,are tested to demonstrate the effectiveness and efficiency of the proposed approach.

关键词： Distributed energy resource(DER) dynamic operating envelope(DOE) feasible region robust optimisation uncertainty modelling unbalanced optimal power flow

FusionNN:A Semantic Feature Fusion Model Based on Multimodal for Web Anomaly Detection

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Computers, Materials & Continua 2024年第5期79卷 2991-3006页

作者： Li Wang Mingshan Xia Hao Hu Jianfang Li Fengyao Hou Gang Chen Institute of high energy physics Chinese Academy of SciencesBeijing100049China Spallation Neutron Source Science Center(SNSSC) Dongguan523803China School of Nuclear Technology University of Chinese Academy of SciencesBeijing100049Chin

With the rapid development of the mobile communication and the Internet,the previous web anomaly detectionand identificationmodels were built relying on security experts’empirical knowledge and attack *** approach can achieve higher detection performance,it requires huge human labor and resources to maintainthe feature *** contrast,semantic feature engineering can dynamically discover new semantic featuresand optimize feature selection by automatically analyzing the semantic information contained in the data itself,thus reducing dependence on prior ***,current semantic features still have the problem ofsemantic expression singularity,as they are extracted from a single semantic mode such as word segmentation,character segmentation,or arbitrary semantic feature *** paper extracts features of web requestsfrom dual semantic granularity,and proposes a semantic feature fusion method to solve the above *** first preprocesses web requests,and extracts word-level and character-level semantic features of URLs viaconvolutional neural network(CNN),*** constructing three loss functions to reduce losses betweenfeatures,labels and *** on the HTTP CSIC 2010,Malicious URLs and HttpParams datasetsverify the *** show that compared withmachine learning,deep learningmethods and BERTmodel,the proposed method has better detection *** it achieved the best detection rate of 99.16%in the dataset HttpParams.

关键词： Feature fusion web anomaly detection multimodal convolutional neural network(CNN) semantic feature extraction

Enhanced heavy and extra heavy oil recovery: Current status and new trends

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PETROLEUM 2024年第3期10卷 399-410页

作者： Gomaa, Sayed Salem, Khalaf G. El-hoshoudy, A. N. Al Azhar Univ Fac Engn Min & Petr Engn Dept Cairo Egypt South Valley egyptian Petr Holding Co GANOPE Dept Reservoir Engn Cairo Egypt egyptian Petr Res Inst PVT Lab Prod Dept Cairo 11727 Egypt egyptian Petr Res Inst EPRI PVT Serv Ctr Cairo 11727 Egypt

Due to the increased demand for energy resources these days, especially due to the Russian-Ukrainian war, the focus of the major countries is turning strongly towards improving oil production, especially heavy and extra heavy oil, which represents 40% of the world oil reserve. Steam-based and thermal (EOR) procedures are promising techniques for recovering heavy oil reservoirs, but they suffer from a sequence of problems and complications that arise after long-term application. These complications comprise steam breakthrough, steam overlap, and steam/rock interactions. This research presents the currently applied techniques to maximize the productivity of heavy oil, such as steam injection, cyclic steam stimulation, in-situ combustion, and steam-assisted gravity drainage. Thermal technologies face numerous obstacles, as they are energy and water-intensive processes that are not environmentally friendly. The research also presents future trends in energy-saving and environmentally friendly techniques that enhance heavy oil recovery through vapor extraction (VAPEX) steam-solvent hybrid techniques, electromagnetic energy, sonication, and nanotechnology. The findings of this review reported that all the presented techniques focus on how to reduce the oil viscosity and in-situ upgrade the crude oil properties. In turn, these enhance both the productivity rate and oil recovery and minimize the production cost. This article can be considered a comprehensive review of thermal recovery methods in heavy and extra-heavy oil, in addition to screening criteria used for each method. (c) 2023 Southwest Petroleum University. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license (http:// ***/licenses/by-nc-nd/4.0/).

关键词： Enhanced oil recovery Heavy crude oil Steam flood Hybrid techniques Nanotechnology IN-SITU-COMBUSTION ASSISTED GRAVITY-DRAINAGE CYCLIC-STEAM-STIMULATION ROCK WETTABILITY VAPOR EXTRACTION INJECTION PERFORMANCE BITUMEN SAGD EOR