检索结果-南通市图书馆

Laguerre expansion on the Heisenberg group and Fourier-Bessel transform on C^n Dedicated to Professor Sheng GONG on the occasion of his 75th birthday

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2006年第11期49卷 1722-1739页

作者： chang der-chen GRIENER Peter Department of Mathematics Georgetown University Washington DC 20057USA Department of Mathematics University of Toronto TorontoON M5S 3G3Canada

Given a principal value convolution on the Heisenberg group Hn = Cn × R, we study the relation between its Laguerre expansion and the Fourier-Bessel expansion of its limit on Cn. We also calculate the Dirichlet kerne... 详细信息

关键词： Heisenberg group, Fourier transform, Laguerre expansion, Bessel functions,Poisson sum, Dirichlet kernel.

Ellipticity on spaces with higher singularities

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2017年第11期60卷 2053-2076页

作者： chang der-chen SCHULZE Bert-Wolfgang Department of Mathematics and Statistics Georgetown University Department of Mathematics Fu Jen Catholic University Institute of Mathematics University of Potsdam

We study corner-degenerate pseudo-differential operators of any singularity order and develop ellipticity based on the principal symbolic hierarchy, associated with the stratification of the underlying space. We construct parametrices within the calculus and discuss the aspect of additional trace and potential conditions along lower-dimensional strata.

关键词： pseudo-differential operators operator-valued symbols Fourier and Mellin transforms

Quaternion H-type group and differential operatorΔ_λ

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2008年第4期51卷 523-540页

作者： chang der-chen Irina MARKINA Department of Mathematics Georgetown University Department of Mathematics University of Bergen

We study the relations between the quaternion H-type group and the boundary of the unit ball on the two-dimensional quaternionic *** orthogonal projection of the space of square integrable functions defined on quaternion H-type group into its subspace of boundary values of q- holomorphic functions is *** precise form of Cauchy-Szeg(?)kernel and the orthogonal projection operator is *** fundamental solution for the operatorΔ_λis found.

关键词： quaternion Siegel upper half space q-holomorphic function subelliptic operator 35H20 42B30

Trace of heat kernel,spectral zeta function and isospectral problem for sub-laplacians

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2009年第12期52卷 2570-2589页

作者： chang der-chen YEUNG Sai-Kee Department of Mathematics Georgetown University Department of Mathematics Purdue University

In this article, we first study the trace for the heat kernel for the sub-Laplacian operator on the unit sphere in ? n+1. Then we survey some results on the spectral zeta function which is induced by the trace of the ... 详细信息

关键词： sub-Laplacian heat kernel CR-isospectral problem Riemannian zeta function Mellin transform pseudo-hermitian structure Primary: 53C17 Secondary: 34K10, 35H20

Musielak–Orlicz–Lorentz Hardy Spaces:Maximal Function,Finite Atomic,and Littlewood–Paley Characterizations with Applications to Dual Spaces and Summability of Fourier Transforms

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2025年第1期41卷 1-77页

作者： Hongchao Jia der-chen chang Ferenc Weisz Dachun Yang Wen Yuan Laboratory of Mathematics and Complex Systems(Ministry of Education of China) School of Mathematical SciencesBeijing Normal UniversityBeijing 100875P.R.China Department of Mathematics and Statistics Georgetown UniversityWashingtonDC 20057USA Graduate Institute of Business Administration College of ManagementFu Jen Catholic UniversityNew Taipei City 242TaiwanChina Department of Numerical Analysis E¨otv¨os L.UniversityP´azm´any P.s´et´any 1/C.Budapest 1117Hungary

Let q∈(0,∞]andϕbe a Musielak-Orlicz function with uniformly lower type p_(ϕ)^(−)∈(0,∞)and uniformly upper type p_(ϕ)^(−)∈(0,∞).In this article,the authors establish various realvariable characterizations of the Musielak-Orlicz-Lorentz Hardy space H^(ϕ,q)(R^(n)),respectively,in terms of various maximal functions,finite atoms,and various Little wood-Paley *** applications,the authors obtain the dual space of Hϕ,q(Rn)and the summability of Fourier transforms from Hϕ,q(Rn)to the Musielak-Orlicz-Lorentz space L^(ϕ,q)(R^(n))when q∈(0,∞)or from the Musielak-Orlicz Hardy space Hϕ(Rn)to Lϕ,∞(Rn)in the critical *** results are new when q∈(0,∞)and also essentially improve the existing corresponding results(if any)in the case q=∞via removing the original assumption thatϕis *** overcome the essential obstacles caused by both thatϕmay not be concave and that the boundedness of the powered Hardy-Littlewood maximal operator on associated spaces of Musielak-Orlicz spaces is still unknown,the authors make full use of the obtained atomic characterization of H^(ϕ,q)(R^(n)),the corresponding results related to weighted Lebesgue spaces,and the subtle relation between Musielak-Orlicz spaces and weighted Lebesgue spaces.

关键词： Musielak-Orlicz-Lorentz Hardy space finite atom duality Littlewood-Paley characterization Fourier transform

Utilizing BP neural networks to accurately reconstruct the tritium depth profile in materials for BIXS

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2025年第1期36卷 176-187页

作者： chen Zhao Wei Jin Yan Shi chang-An chen Yi-Ying Zhao Institute of Materials China Academy of Engineering Physics

β-ray-induced X-ray spectroscopy (BIXS) is a promising method for tritium detection in solid materials because of its unique advantages, such as large detection depth, nondestructive testing capabilities, and low requirements for sample ***, high-accuracy reconstruction of the tritium depth profile remains a significant challenge for this technique. In this study, a novel reconstruction method based on a backpropagation (BP) neural network algorithm that demonstrates high accuracy, broad applicability, and robust noise resistance is proposed. The average reconstruction error calculated using the BP network (8.0%) was much lower than that obtained using traditional numerical methods (26.5%). In addition, the BP method can accurately reconstruct BIX spectra of samples with an unknown range of tritium and exhibits wide applicability to spectra with various tritium distributions. Furthermore, the BP network demonstrates superior accuracy and stability compared to numerical methods when reconstructing the spectra, with a relative uncertainty ranging from 0 to 10%. This study highlights the advantages of BP networks in accurately reconstructing the tritium depth profile from BIXS and promotes their further application in tritium detection.

关键词： BP network Reconstruction problem Ridge regression Tritium detection β-ray-induced X-ray spectroscopy

Climate changes drive phytoplankton community through complementarity and selection effects in a large mesotrophic reservoir

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Oceanology and Limnology 2025年第1期43卷 119-133页

作者： Yue WU Qi YE Siwen chen Lei JIANG Kaining chen Shuzhan MA Yiheng chang Jie LIU Xiaoli SHI State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China College of Nanjing University of Chinese Academy of SciencesNanjing 211135China China State Environmental Protection Key Laboratory of Aquatic Ecosystem Health in the Middle and Lower Reaches of Yangtze River Jiangsu Provincial Academy of Environmental ScienceNanjing 210036China School of Geography and Ocean Science Nanjing UniversityNanjing 210023China

Understanding the response of the phytoplankton community to climate change is essential for reservoir *** analyzed a long-term data series(2009–2020)on the phytoplankton community in a large mesotrophic reservoir in the wet season to investigate the impacts of temperature and precipitation increases caused by climate change on the functioning and trait composition of the phytoplankton *** the last twelve years,the 3-month accumulative precipitation increased from 291.03 mm to 590.91 mm,and the surface water temperature increased from 25.06℃to 26.49℃in wet season,*** changes caused a higher water level,stronger thermal stratification and lower nitrogen concentration in Daxi *** dynamic equilibrium model indicated that the increased precipitation and water temperature-related environmental changes would result in a more diverse and productive phytoplankton *** effects of increasing water temperature and precipitation on the niche complementarity and selection effects within the phytoplankton community were analyzed using structural equation model by means of the functional divergence index and functional evenness index,respectively,elucidating the reasons for the increase in cyanobacteria in the absence of a significant increase in nutrient *** on these results,it is advisable that more stringent phosphorus control standards might be conducted to reduce the risks of cyanobacteria proliferation in the context of global warming.

关键词： global warming climate change reservoir trait-based phytoplankton functional group cyanobacteria

Tranylcypromine upregulates Sestrin 2 expression to ameliorate NLRP3-related noise-induced hearing loss

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第5期20卷 1483-1494页

作者： Xihang chen Zhifeng chen Menghua Li Weiwei Guo Shuolong Yuan Liangwei Xu chang Lin Xi Shi Wei chen Shiming Yang Senior Department of Otolaryngology Head and Neck Surgery Chinese PLA General HospitalChinese PLA Medical SchoolBeijingChina State Key Laboratory of Hearing and Balance Science BeijingChina National Clinical Research Center for Otolaryngologic Diseases BeijingChina Key Laboratory of Hearing Science Ministry of EducationBeijingChina Beijing Key Laboratory of Hearing Impairment Prevention and Treatment BeijingChina Department of Otorhinolaryngology Head and Neck Surgery The First Affiliated Hospital of Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Otolaryngology Head and Neck Surgery The 940th Hospital of Joint Logistics Support Force of Chinese PLALanzhouGansu ProvinceChina Key Laboratory of Tropical Biological Resources of Ministry of Education School of Pharmaceutical SciencesHainan UniversityHaikouHainan ProvinceChina Academician Workstation of Hainan University School of Pharmaceutical SciencesYazhou BaySanyaHainan ProvinceChina

Noise-induced hearing loss is the primary non-genetic factor contributing to auditory ***,there are currently no effective pharmacological interventions for patients with noise-induced hearing ***,we present evidence suggesting that the lysine-specific demethylase 1 inhibitor–tranylcypromine is an otoprotective agent that could be used to treat noise-induced hearing loss,and elucidate its underlying regulatory *** established a mouse model of permanent threshold shift hearing loss by exposing the mice to white broadband noise at a sound pressure level of 120 d B for 4 *** found that tranylcypromine treatment led to the upregulation of Sestrin2(SESN2)and activation of the autophagy markers light chain 3B and lysosome-associated membrane glycoprotein 1 in the cochleae of mice treated with *** noise exposure group treated with tranylcypromine showed significantly lower average auditory brainstem response hearing thresholds at click,4,8,and 16 k Hz frequencies compared with the noise exposure group treated with *** findings indicate that tranylcypromine treatment resulted in increased SESN2,light chain 3B,and lysosome-associated membrane glycoprotein 1 expression after noise exposure,leading to a reduction in levels of 4-hydroxynonenal and cleaved caspase-3,thereby reducing noise-induced hair cell ***,immunoblot analysis demonstrated that treatment with tranylcypromine upregulated SESN2 expression via the autophagy *** treatment also reduced the production of NOD-like receptor family pyrin domaincontaining 3(NLRP3)*** conclusion,our results showed that tranylcypromine treatment ameliorated cochlear inflammation by promoting the expression of SESN2,which induced autophagy,thereby restricting NLRP3-related inflammasome signaling,alleviating cochlear hair cell loss,and protecting hearing *** findings suggest that inhibiting lysine-specific demethylase 1 is a

关键词： 4-hydroxynonenal apoptosis autophagy cleaved caspase-3 inflammation NOD-like receptor family pyrin domain-containing 3(NLRP3) noise-induced hearing loss oxidative stress Sestrin2 tranylcypromine

Long-term trends and response of wet ammonia deposition to changes in anthropogenic emissions in the Pearl River delta of China

在线全文

学校读者我要写书评

暂无评论

JOURNAL OF ENVIRONMENTAL SCIENCES 2025年第5期151卷 373-386页

作者： Li, Mingyue Ye, Lyumeng chang, Ming chen, Weihua He, Shuidi Zhong, Buqing Wang, Xuemei Jinan Univ Inst Environm & Climate Res Guangdong Hongkong Macau Joint Lab Collaborat Inno Guangzhou 511443 Guangdong Peoples R China Minist Ecol & Environm PRC South China Inst Environm Sci Guangzhou 510530 Peoples R China Chinese Acad Sci Key Lab Vegetat Restorat & Management Degraded Eco South China Bot Garden Guangzhou 510650 Peoples R China

The Pearl River Delta (PRD) region has been identified as a significant hotspot of wet ammonium deposition. However, the absence of long-term monitoring data in the area hinders the comprehension of the historical trends and changes in wet NH4+-N deposition in response to emissions, which interferes with the ability to make effective decisions. This study has analyzed the long-term trends of wet NH4+-N deposition flux and has quantified the effect of anthropogenic emissions and meteorological factors at a typical urban site and a typical forest site in the PRD region from 2009 to 2020. It revealed a significant decreasing trend in wet NH4+-N flux in both the typical urban and forest areas of the PRD region, at -6.2%/year (p change alone explained 10%-31%. NH3 emissions have the greatest impact on the urban area among anthropogenic emission factors, while SO2 emissions have the greatest impact on the forest area. Additionally, precipitation was identified as the primary meteorological driver for both sites. Our findings also imply that the benefits of NH3 emissions reductions might not immediately emerge due to interference from weather-related factors.

关键词： Long-term trends Inter-annual variation Wet ammonium deposition Anthropogenic emission change Meteorological condition The Pearl River Delta region