检索结果-南通市图书馆

维普期刊数据库

Tadpole Diagrams and Relativistic Hartree Approximation

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 1996年第4期13卷 261-264页

作者： WU Shi-shu yao yu-jie Research Center for Theoretical Physics Department of PhysicsJilin UniversityChangchun 130023

It is pointed out that the infinite series of the tadpole contribution to the baryon self-energy can be summed rigorously and expressed in a simple *** latter provides a new way for the calculation and explains more c... 详细信息

关键词： form Hartree Approximation

Concept of Excessive Mesons in Nuclei

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 1996年第5期13卷 347-350页

作者： WU Shi-shu yao yu-jie Research Center for Theoretical Physics Department of PhysicsJilin UniversityChangchun 130023

The concept of excessive mesons in nuclei is *** nucleons are identical particles,it is pointed out that the physical content of a meson distribution around a bound nucleon in nuclei is different from that of a meson clotid around a free nucleon,if the effect of the principle of identity cannot be *** difference is enunciated in detail.

关键词： meson neglected identical

A Possible New Effect of Self-Consistency in the Relativistic Hartree-Fock Approximation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2000年第10期17卷 720-722页

作者： yao yu-jie ZHANG Hai-Xia ZHU Jiang-Ming LIU Guang-Zhou WU Shi-Shu Center for Theoretical Physics and Department of Physics Jilin UniversityChangchun 130023

A new effect of self-consistency in the relativistic Hartree-Fock(HF)approximation suggested previously is con firmed by a renormalized calculation with the on-shell renormalization *** self-consistency schemes,ne requiring self-consistency in the HF potential(scheme P)and the other in the baryon propagator(scheme BP),are *** is pointed out that the on-shell renormalization conditions make the self-consistency require-ment in scheme P automatically *** calculated results show that scheme P is a good approximation to scheme BP for the calculation of the baryon propagator and the self-consistency in scheme BP diminishes the continuum part of the spectral representation for the baryon propagator,while scheme P yields a baryon propagator which is the same as the HF result contributed by the single particle part of the above spectral representation ***,it is demonstrated that the region of validity of the quasi-particle approximationmay depend on the renormalization conditions.

关键词： scheme Hartree consistency

Analysis on Marketing Moral Construction of Tourism Enterprise

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Technology Management 2013年第8期 142-144页

作者： yu yao Wang jie Jingdezhen Institute of Jiangxi Jingdezhen Jiangxi 333000

The paper analyzes the current marketing moral status of tourism enterprise, expounds the immoral conduct of marketing of tourism enterprise and the damage on consumer and society, and proposes the countermeasures to ... 详细信息

关键词： tourism enterprise tourism practitioners marketing moral construction

Multi-Robot Cooperative Localization: Time-Varying Unobservable Subspace Analysis and Consistent Algorithm Design

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2024年第5期37卷 1937-1955页

作者： HAO Ning HE Fenghua yao yu School of Astronautics Harbin Institute of Technology

This paper investigates the problem of cooperative localization(CL) for a multi-robot system(MRS) under dynamic measurement topology, which involves a group of robots collectively estimating their poses with respect to a common reference frame using ego-motion measurements and robot-to-robot relative measurements. The authors provide a theoretical analysis of the time-varying unobservable subspace and propose a consistent cooperative localization algorithm. First, the authors introduce the relative measurement graph(RMG) to represent the relative pose measurements obtained by the MRS at each instant. Then, the authors derive the local observability matrix over a time *** equivalent relationship is established between the local observability matrix and the spectral matrices of the RMG. Moreover, the authors present a method for constructing the unobservable subspace based on the RMG under different topology conditions. Based on this analysis, the authors design a consistent cooperative localization algorithm that satisfies the constraints of the time-varying unobservable subspace. An analytical optimal solution is derived for the constrained optimization *** Carlo numerical simulations are conducted to demonstrate the consistency and accuracy of the proposed method.

关键词： Consistency cooperative localization multi-robot system null space relative measurement graph time-varying unobservable subspace

A visual modeling method for spatiotemporal and multidimensional features in epidemiological analysis:Applied COVID-19 aggregated datasets

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Computational Visual Media 2024年第1期10卷 161-186页

作者： yu Dong Christy jie Liang Yi Chen jie Hua School of Computer Science University of Technology SydneySydneyNSW2007Australia Beijing Key Laboratory of Big Data Technology for Food Safety Beijing Technology and Business UniversityBeijing100048China

The visual modeling method enables flexible interactions with rich graphical depictions of data and supports the exploration of the complexities of epidemiological ***,most epidemiology visualizations do not support the combined analysis of objective factors that might influence the transmission situation,resulting in a lack of quantitative and qualitative *** address this issue,we developed a portrait-based visual modeling method called+*** method considers the spatiotemporal features of virus transmission patterns and multidimensional features of objective risk factors in communities,enabling portrait-based exploration and comparison in epidemiological *** applied+msRNAer to aggregate COVID-19-related datasets in New South Wales,Australia,combining COVID-19 case number trends,geo-information,intervention events,and expert-supervised risk factors extracted from local government area-based *** perfected the+msRNAer workflow with collaborative views and evaluated its feasibility,effectiveness,and usefulness through one user study and three subject-driven case *** feedback from experts indicates that+msRNAer provides a general understanding for analyzing comprehension that not only compares relationships between cases in time-varying and risk factors through portraits but also supports navigation in fundamental geographical,timeline,and other factor *** adopting interactions,experts discovered functional and practical implications for potential patterns of long-standing community factors regarding the vulnerability faced by the *** confirmed that+msRNAer is expected to deliver visual modeling benefits with spatiotemporal and multidimensional features in other epidemiological analysis scenarios.

关键词： visual modeling epidemiological analysis spatiotemporal multidimensional COVID-19

石墨烯/有机物复合吸附剂的设计及其在水处理中的应用

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

化学进展 2017年第6期29卷 582-592页

作者：马垚于飞马杰同济大学长江水环境教育部重点实验室上海200092 上海应用技术大学化学与环境工程学院上海201418 江苏盐城环保产业工程研发服务中心盐城224000

当今,资源和能源极度紧缺,改良传统吸附剂,开发高效、低成本、高性能的复合吸附剂成为一大研究课题。石墨烯/有机物复合吸附剂结合了无机材料石墨烯和有机材料的优势,在水处理吸附领域有着广阔的应用前景。目前有关石墨烯/有机物复合吸... 详细信息

当今,资源和能源极度紧缺,改良传统吸附剂,开发高效、低成本、高性能的复合吸附剂成为一大研究课题。石墨烯/有机物复合吸附剂结合了无机材料石墨烯和有机材料的优势,在水处理吸附领域有着广阔的应用前景。目前有关石墨烯/有机物复合吸附剂的设计思路、合成方法及其在水处理中的应用缺少相关的综述。因此,本文对近些年在石墨烯/有机物复合吸附剂的制备及其应用等方面取得的进展进行了综述,探讨和分析了不同类型石墨烯/有机物复合吸附剂的性能以及存在的问题,对其发展方向进行了展望,为后续开展石墨烯/有机物复合吸附剂的相关研究及应用提供了参考。

关键词：石墨烯有机物吸附剂性能水处理

维普期刊数据库

Phase behavior of gas condensate in porous media using real-time computed tomography scanning

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2024年第2期21卷 1032-1043页

作者： Wen-Long Jing Lei Zhang Ai-Fen Li Jun-jie Zhong Hai Sun Yong-Fei Yang yu-Long Cheng Jun yao Institute of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina

The phase behavior of gas condensate in reservoir formations differs from that in pressure-volume-temperature(PVT)cells because it is influenced by porous media in the reservoir *** was used as a sample to investigate the influence of porous media on the phase behavior of the gas *** pore structure was first analyzed using computed tomography(CT)scanning,digital core technology,and a pore network *** sandstone core sample was then saturated with gas condensate for the pressure depletion *** each pressure-depletion state was stable,realtime CT scanning was performed on the *** scanning results of the sample were reconstructed into three-dimensional grayscale images,and the gas condensate and condensate liquid were segmented based on gray value discrepancy to dynamically characterize the phase behavior of the gas condensate in porous *** network models of the condensate liquid ganglia under different pressures were built to calculate the characteristic parameters,including the average radius,coordination number,and tortuosity,and to analyze the changing mechanism caused by the phase behavior change of the gas *** types of condensate liquid(clustered,branched,membranous,and droplet ganglia)were then classified by shape factor and Euler number to investigate their morphological changes dynamically and *** results show that the dew point pressure of the gas condensate in porous media is 12.7 MPa,which is 0.7 MPa higher than 12.0 MPa in PVT *** average radius,volume,and coordination number of the condensate liquid ganglia increased when the system pressure was between the dew point pressure(12.7 MPa)and the pressure for the maximum liquid dropout,Pmax(10.0 MPa),and decreased when it was below *** volume proportion of clustered ganglia was the highest,followed by branched,membranous,and droplet *** study provides crucial experimental evidence for the phase behavior chan

关键词： Gas condensate Pressure depletion Real-time micro-computed tomography scanning Distribution of condensate liquid

维普期刊数据库

Double-nylon purse-string suture in closing postoperative wounds following endoscopic resection of large(≥3 cm)gastric submucosal tumors

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2024年第9期30卷 1143-1153页

作者： Shan-Shan Wang Meng-yao Ji Xu Huang Yan-Xia Li Shi-jie yu yu Zhao Lei Shen Department of Gastroenterology Renmin Hospital of Wuhan UniversityWuhan 430000Hubei provinceChina

BACKGROUND Endoscopic full-thickness resection(EFTR)of gastric submucosal tumors(SMTs)is safe and effective;however,postoperative wound management is equally *** on suturing following EFTR for large(≥3 cm)SMTs is scarce and *** To evaluate the efficacy and clinical value of double-nylon purse-string suture in closing postoperative wounds following EFTR of large(≥3 cm)*** We retrospectively analyzed the data of 85 patients with gastric SMTs in the fundus of the stomach or in the lesser curvature of the gastric body whose wounds were treated with double-nylon purse-string sutures after successful tumor resection at the Endoscopy Center of Renmin Hospital of Wuhan *** operative,postoperative,and follow-up conditions of the patients were *** All tumors were completely resected using EFTR.36(42.35%)patients had tumors located in the fundus of the stomach,and 49(57.65%)had tumors located in the body of the *** patients underwent suturing with double-nylon sutures after EFTR without laparoscopic assistance or further surgical *** fever and stomach pain were reported in 13(15.29%)and 14(16.47%)patients,*** serious adverse events occurred during the intraoperative or postoperative periods.A postoperative review of all patients revealed no residual or recurrent *** Double-nylon purse-string sutures can be used to successfully close wounds that cannot be completely closed with a single nylon suture,especially for large(≥3 cm)EFTR wounds in SMTs.

关键词： Endoscopic full-thickness resection Purse-string suture Postoperative wounds Submucosal tumors