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Instant-Form and Light-Front Hamiltonian and Path Integral Formulations of the Conformally Gauge-Fixed Polyakov D1-Brane Action in the Presence of a Scalar Axion Field and an <i>U</i>(1) Gauge Field
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作者 Usha Kulshreshtha Daya S. Kulshreshtha 《Journal of Modern Physics》 2013年第4期57-69,共13页
Recently we have studied the instant-form quantization (IFQ) and the light-front quantization (LFQ) of the conformally gauge-fixed Polyakov D1 brane action using the Hamiltonian and path integral formulations. The IFQ... Recently we have studied the instant-form quantization (IFQ) and the light-front quantization (LFQ) of the conformally gauge-fixed Polyakov D1 brane action using the Hamiltonian and path integral formulations. The IFQ is studied in the equal world-sheet time framework on the hyperplanes defined by the world-sheet time σ0=τ=constant and the LFQ in the equal light-cone world-sheet time framework, on the hyperplanes of the light-front defined by the light-cone world-sheet time σ+= (τ+σ) =constant. The light-front theory is seen to be a constrained system in the sense of Dirac in contrast to the instant-form theory. However, owing to the gauge anomalous nature of these theories, both of these theories are seen to lack the usual string gauge symmetries defined by the world-sheet reparametrization invariance (WSRI) and the Weyl invariance (WI). In the present work we show that these theories when considered in the presence of background gauge fields such as the NSNS 2-form gauge field Bαβ(σ,τ) or in the presence of U(1) gauge field Aα(σ,τ) and the constant scalar axion field C(σ,τ), then they are seen to possess the usual string gauge symmetries (WSRI and WI). In fact, these background gauge fields are seen to behave as the Wess-Zumino or Stueckelberg fields and the terms containing these fields are seen to behave as Wess-Zumino or Stueckelberg terms for these theories. 展开更多
关键词 Lagrangian and HAMILTONIAN Approach HAMILTONIAN QUANTIZATION path Integral QUANTIZATION LIGHT-FRONT QUANTIZATION Theory of Quantized Fields Constrained Dynamics D-Brane Actions Polyakov Action Strings and Branes String GAUGE Symmetry GAUGE FIELD Theories
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Enhancing Critical Path Problem in Neutrosophic Environment Using Python
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作者 M.Navya Pratyusha Ranjan Kumar 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第9期2957-2976,共20页
In the real world,one of the most common problems in project management is the unpredictability of resources and timelines.An efficient way to resolve uncertainty problems and overcome such obstacles is through an ext... In the real world,one of the most common problems in project management is the unpredictability of resources and timelines.An efficient way to resolve uncertainty problems and overcome such obstacles is through an extended fuzzy approach,often known as neutrosophic logic.Our rigorous proposed model has led to the creation of an advanced technique for computing the triangular single-valued neutrosophic number.This innovative approach evaluates the inherent uncertainty in project durations of the planning phase,which enhances the potential significance of the decision-making process in the project.Our proposed method,for the first time in the neutrosophic set literature,not only solves existing problems but also introduces a new set of problems not yet explored in previous research.A comparative study using Python programming was conducted to examine the effectiveness of responsive and adaptive planning,as well as their differences from other existing models such as the classical critical path problem and the fuzzy critical path problem.The study highlights the use of neutrosophic logic in handling complex projects by illustrating an innovative dynamic programming framework that is robust and flexible,according to the derived results,and sets the stage for future discussions on its scalability and application across different industries. 展开更多
关键词 Classical critical path problem fuzzy critical path problem uncertainty neutrosophic triangular single-valued neutrosophic number neutrosophic critical path problem python programming languag
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LÉVY AREA ANALYSIS AND PARAMETER ESTIMATION FOR FOU PROCESSES VIA NON-GEOMETRIC ROUGH PATH THEORY
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作者 Zhongmin QIAN Xingcheng XU 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1609-1638,共30页
This paper addresses the estimation problem of an unknown drift parameter matrix for a fractional Ornstein-Uhlenbeck process in a multi-dimensional setting.To tackle this problem,we propose a novel approach based on r... This paper addresses the estimation problem of an unknown drift parameter matrix for a fractional Ornstein-Uhlenbeck process in a multi-dimensional setting.To tackle this problem,we propose a novel approach based on rough path theory that allows us to construct pathwise rough path estimators from both continuous and discrete observations of a single path.Our approach is particularly suitable for high-frequency data.To formulate the parameter estimators,we introduce a theory of pathwise Itôintegrals with respect to fractional Brownian motion.By establishing the regularity of fractional Ornstein-Uhlenbeck processes and analyzing the long-term behavior of the associated Lévy area processes,we demonstrate that our estimators are strongly consistent and pathwise stable.Our findings offer a new perspective on estimating the drift parameter matrix for fractional Ornstein-Uhlenbeck processes in multi-dimensional settings,and may have practical implications for fields including finance,economics,and engineering. 展开更多
关键词 Itôintegration Lévy area non-geometric rough path fOU processes pathwise stability long time asymptotic high-frequency data
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Path Planning of Multi-Axis Robotic Arm Based on Improved RRT*
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作者 Juanling Liang Wenguang Luo Yongxin Qin 《Computers, Materials & Continua》 SCIE EI 2024年第10期1009-1027,共19页
An improved RRT∗algorithm,referred to as the AGP-RRT∗algorithm,is proposed to address the problems of poor directionality,long generated paths,and slow convergence speed in multi-axis robotic arm path planning.First,a... An improved RRT∗algorithm,referred to as the AGP-RRT∗algorithm,is proposed to address the problems of poor directionality,long generated paths,and slow convergence speed in multi-axis robotic arm path planning.First,an adaptive biased probabilistic sampling strategy is adopted to dynamically adjust the target deviation threshold and optimize the selection of random sampling points and the direction of generating new nodes in order to reduce the search space and improve the search efficiency.Second,a gravitationally adjustable step size strategy is used to guide the search process and dynamically adjust the step-size to accelerate the search speed of the algorithm.Finally,the planning path is processed by pruning,removing redundant points and path smoothing fitting using cubic B-spline curves to improve the flexibility of the robotic arm.Through the six-axis robotic arm path planning simulation experiments on the MATLAB platform,the results show that the AGP-RRT∗algorithm reduces 87.34%in terms of the average running time and 40.39%in terms of the average path cost;Meanwhile,under two sets of complex environments A and B,the average running time of the AGP-RRT∗algorithm is shortened by 94.56%vs.95.37%,and the average path cost is reduced by 55.28%vs.47.82%,which proves the effectiveness of the AGP-RRT∗algorithm in improving the efficiency of multi-axis robotic arm path planning. 展开更多
关键词 Multi-axis robotic arm path planning improved RRTalgorithm dynamic target deviation threshold dynamic step size path optimization
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Modeling of UAV path planning based on IMM under POMDP framework 被引量:4
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作者 YANG Qiming ZHANG Jiandong SHI Guoqing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第3期545-554,共10页
In order to enhance the capability of tracking targets autonomously of unmanned aerial vehicle (UAV), the partially observable Markov decision process (POMDP) model for UAV path planning is established based on the PO... In order to enhance the capability of tracking targets autonomously of unmanned aerial vehicle (UAV), the partially observable Markov decision process (POMDP) model for UAV path planning is established based on the POMDP framework. The elements of the POMDP model are analyzed and described. The state transfer law in the model can be described by the method of interactive multiple model (IMM) due to the diversity of the target motion law, which is used to switch the motion model to accommodate target maneuvers, and hence improving the tracking accuracy. The simulation results show that the model can achieve efficient planning for the UAV route, and effective tracking for the target. Furthermore, the path planned by this model is more reasonable and efficient than that by using the single state transition law. 展开更多
关键词 PARTIALLY OBSERVABLE MARKOV decision process (POMDP) interactive multiple model (IMM) filtering path planning target tracking state transfer law
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Light-Front Hamiltonian and Path Integral Formulations of the Conformally Gauge-Fixed Polyakov D1 Brane Action 被引量:1
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作者 Usha Kulshreshtha Daya Shankar Kulshreshtha 《Journal of Modern Physics》 2011年第5期335-340,共6页
In a recent paper we have studied the Hamiltonian and path integral quantizations of the conformally gauge-fixed Polyakov D1 brane action in the instant-form of dynamics using the equal world-sheet time framework on t... In a recent paper we have studied the Hamiltonian and path integral quantizations of the conformally gauge-fixed Polyakov D1 brane action in the instant-form of dynamics using the equal world-sheet time framework on the hyperplanes defined by the world- sheet time . In the present work we quantize the same theory in the equal light-cone world-sheet time framework, on the hyperplanes of the light-front defined by the light-cone world-sheet time , using the standard constraint quantization techniques in the Hamiltonian and path integral formulations. The light-front theory is seen to be a constrained system in the sense of Dirac, which is in contrast to the corresponding case of the instant-form theory, where the theory remains unconstrained in the sense of Dirac. The light-front theory is seen to possess a set of twenty six primary second-class contraints. In the present work Hamiltonian and path integral quantizations of this theory are studied on the light-front. 展开更多
关键词 LIGHT-FRONT QUANTIZATION HAMILTONIAN QUANTIZATION path Integral QUANTIZATION Constrained Dynamics Constraint QUANTIZATION GAUGE SYMMETRY STRING GAUGE SYMMETRY STRING Theory D-brane Actions Polyakov Action Light-Cone Quantization.
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Light-Front Hamiltonian, Path Integral and BRST Formulations of the Chern-Simons Theory under Appropriate Gauge-Fixing 被引量:6
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作者 Usha Kulshreshtha Daya Shankar Kulshreshtha James P. Vary 《Journal of Modern Physics》 2010年第6期385-392,共8页
The Chern-Simons theory in two-space one-time dimensions is quantized on the light-front under appropriate gauge-fixing conditions using the Hamiltonian, path integral and BRST formulations.
关键词 HAMILTONIAN QUANTIZATION path Integral QUANTIZATION BRST QUANTIZATION CHERN-SIMONS Theories LIGHT-CONE QUANTIZATION LIGHT-FRONT QUANTIZATION Constrained Dynamics Quantum Electrodynamics Models in Lower Dimensions
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An Improved Bounded Conflict-Based Search for Multi-AGV Pathfinding in Automated Container Terminals
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作者 Xinci Zhou Jin Zhu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2705-2727,共23页
As the number of automated guided vehicles(AGVs)within automated container terminals(ACT)continues to rise,conflicts have becomemore frequent.Addressing point and edge conflicts ofAGVs,amulti-AGVconflict-free path pla... As the number of automated guided vehicles(AGVs)within automated container terminals(ACT)continues to rise,conflicts have becomemore frequent.Addressing point and edge conflicts ofAGVs,amulti-AGVconflict-free path planning model has been formulated to minimize the total path length of AGVs between shore bridges and yards.For larger terminalmaps and complex environments,the grid method is employed to model AGVs’road networks.An improved bounded conflict-based search(IBCBS)algorithmtailored to ACT is proposed,leveraging the binary tree principle to resolve conflicts and employing focal search to expand the search range.Comparative experiments involving 60 AGVs indicate a reduction in computing time by 37.397%to 64.06%while maintaining the over cost within 1.019%.Numerical experiments validate the proposed algorithm’s efficacy in enhancing efficiency and ensuring solution quality. 展开更多
关键词 Automated terminals multi-AGV multi-agent path finding(MAPF) conflict based search(CBS) AGV path planning
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Correlation and Pathway Analysis of the Carbon,Nitrogen,and Phosphorus in Soil-Microorganism-Plant with Main Quality Components of Tea(Camellia sinensis)
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作者 Chun Mao Ji He +3 位作者 Xuefeng Wen Yangzhou Xiang Jihong Feng Yingge Shu 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第3期487-502,共16页
The contents of carbon(C),nitrogen(N),and phosphorus(P)in soil-microorganisms-plant significantly affect tea quality by altering the main quality components of tea,such as tea polyphenols,amino acids,and caffeine.Howev... The contents of carbon(C),nitrogen(N),and phosphorus(P)in soil-microorganisms-plant significantly affect tea quality by altering the main quality components of tea,such as tea polyphenols,amino acids,and caffeine.However,few studies have quantified the effects of these factors on the main quality components of tea.The study aimed to explore the interactions of C,N,and P in soil-microorganisms-plants and the effects of these factors on the main quality components of tea by using the path analysis method.The results indicated that(1)The contents of C,N,and P in soil,microorganisms,and tea plants were highly correlated and collinear,and showed significant correlations with the main quality components of tea.(2)Optimal regression equations were established to esti-mate tea polyphenol,amino acid,catechin,caffeine,and water extract content based on C,N,and P contents in soil,microorganisms,and tea plants(R^(2)=0.923,0.726,0.954,0.848,and 0.883,respectively).(3)Pathway analysis showed that microbial biomass phosphorus(MBP),root phosphorus,branch nitrogen,and microbial biomass carbon(MBC)were the largest direct impact factors on tea polyphenol,catechin,water extracts,amino acid,and caffeine content,respectively.Leaf carbon,root phosphorus,and leaf nitrogen were the largest indirect impact factors on tea polyphenol,catechin,and water extract content,respectively.Leaf carbon indirectly affected tea polyphenol content mainly by altering MBP content.Root phosphorus indirectly affected catechin content mainly by altering soil organic carbon content.Leaf nitrogen indirectly affected water extract content mainly by altering branch nitrogen content.The research results provide the scientific basis for reasonable fertilization in tea gardens and tea quality improvement. 展开更多
关键词 Soil-microorganisms-plant system CARBON NITROGEN PHOSPHORUS tea quality path analysis
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Light-Front Hamiltonian, Path Integral and BRST Formulations of the Chern-Simons-Higgs Theory in the Broken Symmetry Phase
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作者 Usha Kulshreshtha Daya S. Kulshreshtha James P. Vary 《Journal of Modern Physics》 2013年第4期38-48,共11页
In the present work we study the Hamiltonian, path integral and BRST formulations of the Chern-Simons-Higgs theory in two-space one-time dimensions, in the so-called broken symmetry phase of the Higgs potential (where... In the present work we study the Hamiltonian, path integral and BRST formulations of the Chern-Simons-Higgs theory in two-space one-time dimensions, in the so-called broken symmetry phase of the Higgs potential (where the phase φ(xμ) of the complex matter field Φ(xμ) carries the charge degree of freedom of the complex matter field and is akin to the Goldstone boson) on the light-front (i.e., on the hyperplanes defined by the fixed light-cone time). The theory is seen to possess a set of first-class constraints and the local vector gauge symmetry. The theory being gauge-invariant is quantized under appropriate gauge-fixing conditions. The explicit Hamiltonian and path integral quantization is achieved under the above light-cone gauges. The Heisenberg equations of motion of the system are derived for the physical degrees of freedom of the system. Finally the BRST quantization of the system is achieved under appropriate BRST gauge-fixing, where the BRST symmetry is maintained even under the BRST light-cone gauge-fixing. 展开更多
关键词 LIGHT-FRONT QUANTIZATION HAMILTONIAN QUANTIZATION path Integral QUANTIZATION BRST QUANTIZATION Constrained Dynamics Gauge SYMMETRY Chern-Simons-Higgs Theory Broken SYMMETRY Phase HIGGS Potential Spontaneous SYMMETRY Breaking
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A Cascading Fault Path Prediction Method for Integrated Energy Distribution Networks Based on the Improved OPA Model under Typhoon Disasters
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作者 Yue He YaxiongYou +4 位作者 ZhianHe Haiying Lu Lei Chen Yuqi Jiang Hongkun Chen 《Energy Engineering》 EI 2024年第10期2825-2849,共25页
In recent times,the impact of typhoon disasters on integrated energy active distribution networks(IEADNs)has received increasing attention,particularly,in terms of effective cascading fault path prediction and enhance... In recent times,the impact of typhoon disasters on integrated energy active distribution networks(IEADNs)has received increasing attention,particularly,in terms of effective cascading fault path prediction and enhanced fault recovery performance.In this study,we propose a modified ORNL-PSerc-Alaska(OPA)model based on optimal power flow(OPF)calculation to forecast IEADN cascading fault paths.We first established the topology and operational model of the IEADNs,and the typical fault scenario was chosen according to the component fault probability and information entropy.The modified OPA model consisted of two layers:An upper-layer model to determine the cascading fault location and a lower-layer model to calculate the OPF by using Yalmip and CPLEX and provide the data to update the upper-layer model.The approach was validated via the modified IEEE 33-node distribution system and two real IEADNs.Simulation results showed that the fault trend forecasted by the novel OPA model corresponded well with the development and movement of the typhoon above the IEADN.The proposed model also increased the load recovery rate by>24%compared to the traditional OPA model. 展开更多
关键词 IEADNs OPA model cascading fault path prediction fault probability optimal power flow typical fault scenario
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A Study on Optimizing the Double-Spine Type Flow Path Design for the Overhead Transportation System Using Tabu Search Algorithm
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作者 Nguyen Huu Loc Khuu Thuy Duy Truong +3 位作者 Quoc Dien Le Tran Thanh Cong Vu Hoa Binh Tran Tuong Quan Vo 《Intelligent Automation & Soft Computing》 2024年第2期255-279,共25页
Optimizing Flow Path Design(FPD)is a popular research area in transportation system design,but its application to Overhead Transportation Systems(OTSs)has been limited.This study focuses on optimizing a double-spine f... Optimizing Flow Path Design(FPD)is a popular research area in transportation system design,but its application to Overhead Transportation Systems(OTSs)has been limited.This study focuses on optimizing a double-spine flow path design for OTSs with 10 stations by minimizing the total travel distance for both loaded and empty flows.We employ transportation methods,specifically the North-West Corner and Stepping-Stone methods,to determine empty vehicle travel flows.Additionally,the Tabu Search(TS)algorithm is applied to branch the 10 stations into two main layout branches.The results obtained from our proposed method demonstrate a reduction in the objective function value compared to the initial feasible solution.Furthermore,we explore howchanges in the parameters of the TS algorithm affect the optimal result.We validate the feasibility of our approach by comparing it with relevant literature and conducting additional tests on layouts with 20 and 30 stations. 展开更多
关键词 Overhead transportation systems tabu search double-spine layout transportationmethod empty travel flow path design
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Feynman Path Integral Using Operator Integration in Banach Space
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作者 Reza R. Ahangar Erbil Cetin Serife Muge Ege 《Journal of Applied Mathematics and Physics》 2024年第2期432-444,共13页
Feynman-Path Integral in Banach Space: In 1940, R.P. Feynman attempted to find a mathematical representation to express quantum dynamics of the general form for a double-slit experiment. His intuition on several slits... Feynman-Path Integral in Banach Space: In 1940, R.P. Feynman attempted to find a mathematical representation to express quantum dynamics of the general form for a double-slit experiment. His intuition on several slits with several walls in terms of Lagrangian instead of Hamiltonian resulted in a magnificent work. It was known as Feynman Path Integrals in quantum physics, and a large part of the scientific community still considers them a heuristic tool that lacks a sound mathematical definition. This paper aims to refute this prejudice, by providing an extensive and self-contained description of the mathematical theory of Feynman Path Integration, from the earlier attempts to the latest developments, as well as its applications to quantum mechanics. About a hundred years after the beginning of modern physics, it was realized that light could in fact show behavioral characteristics of both waves and particles. In 1927, Davisson and Germer demonstrated that electrons show the same dual behavior, which was later extended to atoms and molecules. We shall follow the method of integration with some modifications to construct a generalized Lebesgue-Bochner-Stieltjes (LBS) integral of the form , where u is a bilinear operator acting in the product of Banach spaces, f is a Bochner summable function, and μ is a vector-valued measure. We will demonstrate that the Feynman Path Integral is consistent and can be justified mathematically with LBS integration approach. 展开更多
关键词 Feynman path Integral Lebesgue-Bochner-Stieltjes Integral Operator Integral Particle-Wave Function Operator Integration Position and Momentum Operators
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The Influencing Factors and Improvement Paths of Applied Talent Training Mode under the Digital Informatization
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作者 Fuze Fang Huanyang Zeng +3 位作者 Xiaojun Ke Xin Li Binsheng Chen Bohang Chen 《Sociology Study》 2024年第4期183-189,共7页
This study takes the human resource management major of Guangzhou Institute of Science and Technology as an example to discuss the factors influencing the applied talent training mode and improvement paths under digit... This study takes the human resource management major of Guangzhou Institute of Science and Technology as an example to discuss the factors influencing the applied talent training mode and improvement paths under digital informatization.The research points out that digital informatization poses new challenges and opportunities to higher education and requires the applied talent training mode to practice and innovate.This study identified five key influencing factors of the applied talent training mode under digital informatization:curriculum setting,teaching methods,faculty structure,practical teaching,and student training.This research presents the improvement paths,including optimizing curriculum settings,innovating teaching methods,adjusting teacher structure,improving practical teaching,and creating student training.Implementing these paths will help students master the latest knowledge and skills of digital informatization,improve their practical ability and innovative thinking to meet the social demand for human resource management professionals,and promote the development of higher education system. 展开更多
关键词 digital informatization application talents training mode influencing factors improvement paths higher education
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Exploration of the Integration of Curriculum Ideology and Politics into the Educational Pathway of Standardized Training for General Practice Residents
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作者 Zhuan Huang Yaodong Li +4 位作者 Lina Ma Rui Xu Fang Yang Yingpeng Shi Junlin Liu 《Journal of Contemporary Educational Research》 2024年第5期91-96,共6页
In recent years,the national higher education reform has proposed the concept of curriculum ideological and political education as a major element.This integration into the standardized training of general practice re... In recent years,the national higher education reform has proposed the concept of curriculum ideological and political education as a major element.This integration into the standardized training of general practice residents(commonly referred to as general resident training)is an unavoidable trend in the teaching field.Based on the actual situation of our unit at The First Affiliated Hospital of Xi’an Medical University,this paper emphasizes the necessity of incorporating ideological and political education into the general resident training curriculum,despite the absence of pertinent practical experience in how to effectively incorporate such courses into comprehensive residential training.In our hospital,we must assess the ideological and political education in the curriculum of general resident training,proposing a scientific,reasonable ideological and political education concept system for general practice courses,integrating ideological and political education with general practice resident training,and strengthening the team of ideological and political education physicians to teach them to carry out such education,this would foster enthusiasm and initiative.Strengthening admission education and training for general practice resident training,as well as regularly hosting symposiums to share ideas and understand the mission of doctors can provide effective experience for ideological and political education in general resident training courses. 展开更多
关键词 Curriculum ideological and political education General practice General practice residents Standardized training Education path EXPLORATION
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Nonlinear Relationship and Its Evolutionary Trace between Node Degree and Average Path Length of China Aviation Network Based on Complex Network
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作者 Cheng Xiangjun Zhang Xiaoxuan Li Yangqi 《Journal of Traffic and Transportation Engineering》 2024年第1期11-22,共12页
In order to reveal the complex network characteristics and evolution principle of China aviation network,the relationship between the node degree and the average path length of China aviation network in 1988,1994,2001... In order to reveal the complex network characteristics and evolution principle of China aviation network,the relationship between the node degree and the average path length of China aviation network in 1988,1994,2001,2008 and 2015 was studied.According to the theory and method of complex network,the network system was constructed with the city where the airport was located as the network node and the airline as the edge of the network.On the basis of the statistical data,the node average path length of China aviation network in 1988,1994,2001,2008 and 2015 was calculated.Through regression analysis,it was found that the node degree had a logarithmic relationship with the average length of node path,and the two parameters of the logarithmic relationship had linear evolutionary trace.Key word:China aviation network,complex network,node degree,average length of node path,logarithmic relationship,evolutionary trace. 展开更多
关键词 China aviation network complex network node degree average length of node path logarithmic relationship evolutionary trace.
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Nonlinear Relationship and Its Evolutionary Trace between Average Degree and Average Path Length of Edge Vertices of China Aviation Network Based on Complex Network
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作者 Cheng Xiangjun Chen Xumei Guo Jianyuan 《Journal of Traffic and Transportation Engineering》 2024年第5期224-237,共14页
In order to reveal the complex network characteristics and evolution principle of China aviation network,the relationship between the average degree and the average path length of edge vertices of China aviation netwo... In order to reveal the complex network characteristics and evolution principle of China aviation network,the relationship between the average degree and the average path length of edge vertices of China aviation network in 1988,1994,2001,2008 and 2015 was studied.According to the theory and method of complex network,the network system was constructed with the city where the airport was located as the network node and the airline as the edge of the network.On the basis of the statistical data,the average degree and average path length of edge vertices of China aviation network in 1988,1994,2001,2008 and 2015 were calculated.Through regression analysis,it was found that the average degree had a logarithmic relationship with the average path length of edge vertices and the two parameters of the logarithmic relationship had linear evolutionary trace. 展开更多
关键词 China aviation network complex network average degree of edge vertices average path length of edge vertices logarithmic relationship evolutionary trace
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Light-Front Hamiltonian and Path Integral Formulations of the Conformally Gauge-Fixed Polyakov D1 Brane Action with a Scalar Dilation Field
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作者 Usha Kulshreshtha Daya Shankar Kulshreshtha 《Journal of Modern Physics》 2011年第8期826-833,共8页
Recently we have studied the instant-form quantization (IFQ) of the conformally gauge-fixed Polyakov D1 brane action with and without a scalar dilaton field using the Hamiltonian and path integral formulations in the ... Recently we have studied the instant-form quantization (IFQ) of the conformally gauge-fixed Polyakov D1 brane action with and without a scalar dilaton field using the Hamiltonian and path integral formulations in the equal world-sheet time framework on the hyperplanes defined by the world- sheet time σ0=τ=constant . The light-front quantization (LFQ) of this theory without a scalar dilaton field has also been studied by us recently. In the present work we study the LFQ of this theory in the equal light-cone world-sheet time framework, on the hyperplanes of the light-front defined by the light-cone world-sheet time σ+=τ+σ=constant , using the Hamiltonian and path integral formulations. The light-front theory is seen to be a constrained system in the sense of Dirac. The light-front theory is seen to possess a set of twenty seven primary second-class contraints. In the present work Hamiltonian and path integral quantizations of this theory are studied on the light-front. 展开更多
关键词 LIGHT-FRONT QUANTIZATION HAMILTONIAN QUANTIZATION path Integral QUANTIZATION Constrained Dynamics Constraint QUANTIZATION GAUGE SYMMETRY STRING GAUGE SYMMETRY STRING Theory D-brane Actions Polyakov Action Light-Cone QUANTIZATION
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A Reanalysis of the Two Swimmers Problem, as Frequent Model of Michelson’s Interferometric Experiment Demonstrating that Transversal Path Is Not an Isosceles but a Right Triangle and the Race Will End in a Tie
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作者 Ioan Has Simona Miclaus Aurelian Has 《Journal of Applied Mathematics and Physics》 2018年第7期1507-1521,共15页
The article initially reviews various works describing the physical model (PM) of Michelson’s interferometric experiment (ME), represented by the race between two swimmers Sw1, Sw2 (or boats, or planes, or sound sign... The article initially reviews various works describing the physical model (PM) of Michelson’s interferometric experiment (ME), represented by the race between two swimmers Sw1, Sw2 (or boats, or planes, or sound signals, etc.). The two swimmers must each swim the same distance, but Sw1 will swim along the river flow, and Sw2 will swim perpendicularly to this direction. In all such works, it is considered that Sw2’s path will require less time and that it will reach the start point first. However, in this work, it has been determined that in order to make this possible, Sw2 must not observe the orthogonality rule of his start direction. This action would be deceitful to the arbiters and thus considered as non-fair-play towards Sw1. The article proves by swimming times calculus, that if the fair-play rules are observed, then the correct crosswise path (in water reference frame) is a right triangle instead of the isosceles triangle considered by Michelson. Consequently, the two times shall be perfectly equal and the race ends in a tie, and the myth of Sw2 as the race winner shall be debunked. Note that the same result shall also be applicable to Michelson’s interferometric experiment (ME) as well as to any similar experiment. Therefore, utilising the isosceles triangle as the transversal path in PM and also in ME is an erroneous act. 展开更多
关键词 Michelson EXPERIMENT TWO SWIMMERS Model Swimming Times Calculation Right TRIANGLE Correct TRANSVERSAL path Error of Isosceles TRIANGLE for TRANSVERSAL path
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An Optimal Feed Interpolator Based on G^2 Continuous Bézier Curves for High-Speed Machining of Linear Tool Path 被引量:6
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作者 Yongqiao Jin Sheng Zhao Yuhan Wang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第3期109-118,共10页
A numerical control (NC) tool path of digital CAD model is widely generated as a set of short line segments in machining. However, there are three shortcomings in the linear tool path, such as discontinuities of tange... A numerical control (NC) tool path of digital CAD model is widely generated as a set of short line segments in machining. However, there are three shortcomings in the linear tool path, such as discontinuities of tangency and curvature, huge number of line segments, and short lengths of line segments. These disadvantages hinder the development of high speed machining. To smooth the linear tool path and improve machining efficiency of short line segments, this paper presents an optimal feed interpolator based on G^2 continuous Bézier curves for the linear tool path. First, the areas suitable for fitting are screened out based on the geometric characteristics of continuous short segments (CSSs). CSSs in every area are compressed and fitted into a G^2 Continuous Bézier curve by using the least square method. Then a series of cubic Bézier curves are generated. However, the junction between adjacent Bézier curves is only G^0 continuous. By adjusting the control points and inserting Bézier transition curves between adjacent Bézier curves, the G^2 continuous tool path is constructed. The fitting error is estimated by the second-order Taylor formula. Without iteration, the fitting algorithm can be implemented in real-time environment. Second, the optimal feed interpolator considering the comprehensive constraints (such as the chord error constraint, the maximum normal acceleration, servo capacity of each axis, etc.) is proposed. Simulation and experiment are conducted. The results shows that the proposed method can generate smooth path, decrease the amount of segments and reduce machining time for machining of linear tool path. The proposed research provides an effective method for high-speed machining of complex 2-D/3-D profiles described by short line segments. 展开更多
关键词 G^2 CONTINUOUS path Least SQUARE method High-speed MACHINING CONTINUOUS short SEGMENTS Optimal FEED INTERPOLATOR Data compression
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