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CSEE Journal of Power and Energy Systems 2024年第2期10卷 584-592页

作者： Zhi Ding Tianyao ji Mengshi Li q.H.Wu School of Electric Power Engineering South China University of Technology(SCUT)Guangzhou 510641China

In this paper, a novel signal processing method combining mathematical morphology (MM) and Walsh theory is proposed, which uses Walsh functions to control the structuring element (SE) and MM operators. Based on the Walsh-MM method, a scheme for power q.ality disturbances detection and classification is developed, which involves three steps: denoising, feature extraction and morphological clustering. First, various evolution rules of Walsh function are used to generate groups of SEs for the multiscale Walsh-ordered morphological operation, so the original signal can be denoised. Next, the fundamental wave of the denoised signal is suppressed by Hadamard matrix;thus, disturbances can be extracted. Finally, the Walsh power spectrum of the waveform extracted in the previous step is calculated, and the parameters of which are taken by morphological clustering to classify the disturbances. Simulation results reveal the proposed scheme can effectively detect and classify disturbances, and the Walsh-MM method is less affected by noise and only involves simple calculation, which has a potential to be implemented in hardware and more suitable for real-time application.

关键词： Hadamard matrix mathematical morphology morphological clustering power q.ality disturbance Walsh theory

Construction and Validity of Chinese Translation of the Universal Mental Health Literacy Scale for Adolescents

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International Journal of Mental Health Promotion 2024年第8期26卷 671-677页

作者： Wang q. ji Y. Chen K. Li K. jia F. Peng T. School of Education and Psychology University of Jinan Jinan 250022 China Psychology Research Group Jinan Quanjing Middle School Jinan 250024 China

Background: In this study, the Universal Mental Health Literacy Scale for Adolescents (UMHL-A) was revised and tested for its reliability and validity in Chinese middle school students, thus establishing a useful tool for assessing the mental health of individuals in this occupation. Methods: Our sample comprised 1208 junior high school students (58.85% male), aged between 11 and 15 years old. The Chinese version of the scale includes a mental health attitude subscale and mental health knowledge subscale, including attitudes towards seeking help, attitudes related to stigma, general mental health knowledge, and knowledge about specific mental illnesses, encapsulated in a total of 17 items. A series of psychometric analyses such as exploratory factor analysis (EFA), confirmatory factor analysis (CFA), and internal consistency reliability estimation were carried out in this study. Results: The results of the CFA indicated that the two-factor model had an acceptable model fit (Attitude (UMHL-A Likert): χ2/df = 4.107; RMSEA = 0.072; SRMR = 0.045; TLI = 0.932; CFI = 0.954; Knowledge (UMHL-A T/F): χ2/df = 3.647; RMSEA = 0.066; SRMR = 0.044; TLI = 0.923; CFI = 0.945). The Cronbach’s alpha coefficient of subscales of the Chinese version UMHL-A were 0.80 and 0.78, respectively. Conclusion: In general, the Chinese version of the Universal Mental Health Literacy Scale for adolescents has good reliability and validity and can be used as a tool to measure the mental health literacy of Chinese adolescents. © 2024 The Authors.

关键词： adolescents Chinese Mental health literacy validity

Precipitation of multi-type nano-q.asicrystals in a Mg-Zn-Y alloy

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Journal of Magnesium and Alloys 2024年第3期12卷 997-1008页

作者： W.Z.Wang X.Z.Zhou L.F.Zhang H.q.Ye Z.q.Yang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of ScienceShenyang 110016China ji Hua Laboratory Foshan 528251China Foshan University Foshan 528231China

Mg-6Zn-1Y(at.%)ribbons with strengthening precipitates of multi-type nanoq.asicrystals were prepared by melt-spinning followed by aging *** evolution of the rapidly solidified ribbons during isothermal aging was comprehensively studied using various electron microscopy *** new kinds of decagonal q.asicrystals were formed in aged ribbons,in addition to precipitation of nanometer icosahedral ***-resolution observations reveal that both decagonal q.asicrystals can be modeled by q.asiperiodic tiling with decagonal clusters of 2.5 nm in diameter,but overlap of neighboring clusters in both decagonal q.asicrystals is different from the Gummelt model observed in other q.asicrystals.A shell composed of complex Laves Mg-Zn domains was formed surrounding each decagonal q.asicrystal precipitate upon prolonged *** addition,all kinds of nanoprecipitates exhibit excellent structure and size stability at 573 *** findings may have implications for not only fundamental studies about q.asicrystals,but also microstructural manipulation of high-performance Mg alloys.

关键词： q.asicrystal Mg alloys Rapid solidification Scanning-transmission electron microscopy.

Differential Operator Approach to■q.antum Groups and Their Oscillator Representations

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1360-1374页

作者： Zhao Bing FAN ji Cheng GENG Shao Long HAN College of Mathematical Science Harbin Engineering UniversityHarbin 150001P.R.China

For a q.asi-split Satake diagram,we define a modified q.Weyl algebra,and show that there is an algebra homomorphism between it and the corresponding■q.antum *** other words,we provide a differential operator approach to■q.antum ***,the oscillator representations of■q.antum groups are *** crystal basis of the irreducible subrepresentations of these oscillator representations are constructed.

关键词： ■q.antum group differential operator oscillator representation crystal basis

Recent advances in promising drugs for primary prevention of gastroesophageal variceal bleeding with cirrhotic portal hypertension

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 4-13页

作者： ji-Yao Sheng Zi-Fan Meng q.ao Li Yong-Sheng Yang Department of Hepatobiliary and Pancreatic Surgery the Second Hospital of Jilin UniversityChangchun 130041China jilin Engineering Laboratory for Translational Medicine of Hepatobiliary and Pancreatic Diseases the Second Hospital of Jilin UniversityChangchun 130041China

Background:Gastroesophageal variceal bleeding is one of the most severe complications of patients with *** primary prevention drugs,including non-selectiveβ-blockers,have effectively reduced the incidence of bleeding,their efficacy is limited due to side effects and related *** recent advances in precision medicine,precise drug treatment provides better treatment *** sources:Literature search was conducted in PubMed,MEDLINE and Web of Science for relevant articles published up to May *** on clinical trials was obtained from https://***/and http://***/.Results:The in-depth understanding of the pathogenesis and advances of portal hypertension has enabled the discovery of multiple molecular targets for promising *** to the site of action,these drugs could be classified into four classes:intrahepatic,extrahepatic,both intrahepatic and extrahepatic targets and *** these classes of drugs offer advantages over traditional treatments in prevention of gastroesophageal variceal bleeding in patients with cirrhotic portal ***:This review classified and summarized the promising drugs,which prevent gastroesophageal variceal bleeding by targeting specific markers of pathogenesis of portal hypertension,demonstrating the significance of using the precision medicine strategy to discover and develop promising drugs for the primary prevention of gastroesophageal variceal bleeding in patients with cirrhotic portal hypertension.

关键词： Cirrhotic portal hypertension Target drug Primary prevention Bleeding

Accurate simulations of pure-viscoacoustic wave propagation in tilted transversely isotropic media

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Petroleum Science 2024年第2期21卷 866-884页

作者： q.ang Mao jian-Ping Huang Xin-Ru Mu ji-Dong Yang Yu-jian Zhang Geosciences Department China University of Petroleum(East China)Qingdao266580ShandongChina Pilot National Laboratory for Marine Science and Technology(q.ngdao) Qingdao266207ShandongChina

Forward modeling of seismic wave propagation is crucial for the realization of reverse time migration(RTM) and full waveform inversion(FWI) in attenuating transversely isotropic media. To describe the attenuation and anisotropy properties of subsurface media, the pure-viscoacoustic anisotropic wave eq.ations are established for wavefield simulations, because they can provide clear and stable wavefields. However, due to the use of several approximations in deriving the wave eq.ation and the introduction of a fractional Laplacian approximation in solving the derived eq.ation, the wavefields simulated by the previous pure-viscoacoustic tilted transversely isotropic(TTI) wave eq.ations has low accuracy. To accurately simulate wavefields in media with velocity anisotropy and attenuation anisotropy, we first derive a new pure-viscoacoustic TTI wave eq.ation from the exact complex-valued dispersion formula in viscoelastic vertical transversely isotropic(VTI) media. Then, we present the hybrid finite-difference and low-rank decomposition(HFDLRD) method to accurately solve our proposed pure-viscoacoustic TTI wave eq.ation. Theoretical analysis and numerical examples suggest that our pure-viscoacoustic TTI wave eq.ation has higher accuracy than previous pure-viscoacoustic TTI wave eq.ations in describing q.P-wave kinematic and attenuation characteristics. Additionally, the numerical experiment in a simple two-layer model shows that the HFDLRD techniq.e outperforms the hybrid finite-difference and pseudo-spectral(HFDPS) method in terms of accuracy of wavefield modeling.

关键词： Pure-viscoacoustic TTI wave eq.ation Attenuation anisotropy Seismic modeling Low-rank decomposition method

Research on the Encapsulation Device for Lunar Samples

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Chinese Journal of Mechanical Engineering 2024年第3期37卷 104-117页

作者： Yonggang Du Chunyong Wang Haoling Li Ying Zhou Ming ji Xuesong Wang Lanzhou Institute of Physics CASTLanzhou 730000China

The encapsulation of lunar samples is a core research area in the third phase of the Chinese Lunar Exploration *** seal assembly,opening and closing mechanism(OCM),and locking mechanism are the core components of the encapsulation device of the lunar samples,and the req.irements of a tight seal,lightweight,and low power make the design of these core components *** this study,a combined sealing assembly,OCM,and locking mechanism were investigated for the *** sealing architecture consists of rubber and an Ag-In alloy,and a theory was built to analyze the *** of the electroplate Au coating on the knife-edge revealed that the hermetic seal can be significantly *** driving principle for coaxial double-helical pairs was investigated and used to design the ***,a locking mechanism was created using an electric initiating explosive device with orifice *** optimizing the design,the output parameters were adjusted to meet the req.irements of the lunar *** experimental results showed that the helium leak rate of the test pieces were not more than 5×10^(-11) Pa·m^(3)·s^(-1),the minimum power of the OCM was 0.3 W,and the total weight of the principle prototype was 2.9 *** explosive driven locking mechanism has low *** investigation solved the difficulties in achieving tight seal,light weight,and low power for the lunar explorer,and the results can also be used to explore other extraterrestrial objects in the future.

关键词： Lunar samples Encapsulation Vacuum seal Mechanism

Taiji-Tianq.n-LISA network:Precisely measuring the Hubble constant using both bright and dark sirens

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 59-77页

作者： Shang-jie jin Ye-Zhu Zhang ji-Yu Song jing-Fei Zhang Xin Zhang Key Laboratory of Cosmology and Astrophysics(Liaoning)&College of Sciences Northeastern UniversityShenyang 110819China Key Laboratory of Data Analytics and Optimization for Smart Industry(Ministry of Education) Northeastern UniversityShenyang 110819China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern UniversityShenyang 110819China

In the coming decades,the space-based gravitational-wave(GW)detectors such as Taiji,Tianq.n,and LISA are expected to form a network capable of detecting millihertz GWs emitted by the mergers of massive black hole binaries(MBHBs).In this work,we investigate the potential of GW standard sirens from the Taiji-Tianq.n-LISA network in constraining cosmological *** the optimistic scenario in which electromagnetic(EM)counterparts can be detected,we predict the number of detectable bright sirens based on three different MBHB population models,i.e.,popⅢ,q.d,and *** results show that the TaijiTianq.n-LISA network alone could achieve a constraint precision of 0.9%for the Hubble constant,meeting the standard of precision ***,the Taiji-Tianq.n-LISA network could effectively break the cosmological parameter degeneracies generated by the CMB data,particularly in the dynamical dark energy *** combined with the CMB data,the joint CMB+Taiji-Tianq.n-LISA data offerσ(w)=0.036 in the wCDM model,which is close to the latest constraint result obtained from the CMB+SN *** also consider a conservative scenario in which EM counterparts are not *** to the precise sky localizations of MBHBs by the Taiji-Tianq.n-LISA network,the constraint precision of the Hubble constant is expected to reach 1.2%.In conclusion,the GW standard sirens from the Taiji-Tianq.n-LISA network will play a critical role in helping solve the Hubble tension and shedding light on the nature of dark energy.

关键词： space-based gravitational wave detection standard sirens the Taiji-Tianq.n-LISA network the Hubble constant dark energy

Ceramic-based meta-material absorber with high-temperature stability

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Rare Metals 2024年第9期43卷 4433-4440页

作者： Xing-Cong Chen Wei-jia Luo Run-Ni Zhao Yong-Zheng Wen ji Zhou State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua University

With the continuous exploration of uncharted and extreme environments,enhanced temperature robustness of passive devices has become particularly *** this study,a ceramic-based meta-material absorber with exceptional temperature stability is developed using a fusion design approach that combines rare metal-based tungsten bronze structural ceramics and ***,the absorbance of the meta-material array based on Mie resonance exceeds 49.0%in both waveguides and free space,approaching the theoretical *** to impedance analysis,the absorption performance can be distinctly correlated with the dielectric loss （q.f）.Notably,the high-temperature robustness is verified to still be effective at 400℃.These advancements in our design allow for the use of monolithic materials in fabricating temperature-stable perfect absorbers,providing greater freedom in the dielectric performance and expanding their potential applications,including in space exploration and 5G millimeter-wave scenarios.

关键词： Meta-material absorber Microwave absorption Miniaturization Rare metal-based ceramics Temperature robustness

Impact of an oligosaccharide-based polymer on the metabolic profiles and microbial ecology of weanling pigs experimentally infected with a pathogenic ***

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Journal of Animal Science and Biotechnology 2024年第2期15卷 749-764页

作者： Kwangwook Kim Cynthia jinno Xunde Li David Bravo Eric Cox Peng ji Yanhong Liu Department of Animal Science University of CaliforniaDavisCA 95616USA Department of Animal Science Michigan State UniversityEast LansingMI 48824USA Cedars-Sinai Medical Center Los AngelesCA 90084USA School of Veterinary Medicine University of CaliforniaDavisCA 95616USA Pancosma|ADM 1180 RolleSwitzerland Nutreco Exploration NutrecoThe Netherlands Department of Virology Parasitology and ImmunologyGhent University9000 GhentBelgium Department of Nutrition University of CaliforniaDavisCA 95616USA

Background Our previous study has reported that supplementation of oligosaccharide-based polymer enhances gut health and disease resistance of pigs infected with enterotoxigenic ***(ETEC)F18 in a manner similar to *** objective of this study was to investigate the impacts of oligosaccharide-based polymer or antibiotic on the host metabolic profiles and colon microbiota of weaned pigs experimentally infected with ETEC *** Multivariate analysis highlighted the differences in the metabolic profiles of serum and colon digesta which were predominantly found between pigs supplemented with oligosaccharide-based polymer and *** relative abundance of metabolic markers of immune responses and nutrient metabolisms,such as amino acids and carbohydrates,were significantly differentiated between the oligosaccharide-based polymer and antibiotic groups(q.0.2 and fold change>2.0).In addition,pigs in antibiotic had a reduced(P<0.05)relative abundance of Lachnospiraceae and Lactobacillaceae,whereas had greater(P<0.05)Clostridiaceae and Streptococcaceae in the colon digesta on d 11 post-inoculation(PI)compared with d 5 *** The impact of oligosaccharide-based polymer on the metabolic and microbial profiles of pigs is not fully understood,and further exploration is ***,current research suggest that various mechanisms are involved in the enhanced disease resistance and performance in ETEC-challenged pigs by supplementing this polymer.

关键词： Carbadox Colon microbiota Enterotoxigenic E.coli F18 Metabolomics Oligosaccharide-based polymer Weaned pigs