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Oriented Bounding Box Object Detection Model Based on Improved YOLOv8 被引量:1
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作者 ZHAO Xin-kang SI Zhan-jun 《印刷与数字媒体技术研究》 CAS 北大核心 2024年第4期67-75,114,共10页
In the study of oriented bounding boxes(OBB)object detection in high-resolution remote sensing images,the problem of missed and wrong detection of small targets occurs because the targets are too small and have differ... In the study of oriented bounding boxes(OBB)object detection in high-resolution remote sensing images,the problem of missed and wrong detection of small targets occurs because the targets are too small and have different orientations.Existing OBB object detection for remote sensing images,although making good progress,mainly focuses on directional modeling,while less consideration is given to the size of the object as well as the problem of missed detection.In this study,a method based on improved YOLOv8 was proposed for detecting oriented objects in remote sensing images,which can improve the detection precision of oriented objects in remote sensing images.Firstly,the ResCBAMG module was innovatively designed,which could better extract channel and spatial correlation information.Secondly,the innovative top-down feature fusion layer network structure was proposed in conjunction with the Efficient Channel Attention(ECA)attention module,which helped to capture inter-local cross-channel interaction information appropriately.Finally,we introduced an innovative ResCBAMG module between the different C2f modules and detection heads of the bottom-up feature fusion layer.This innovative structure helped the model to better focus on the target area.The precision and robustness of oriented target detection were also improved.Experimental results on the DOTA-v1.5 dataset showed that the detection Precision,mAP@0.5,and mAP@0.5:0.95 metrics of the improved model are better compared to the original model.This improvement is effective in detecting small targets and complex scenes. 展开更多
关键词 Remote sensing image Oriented bounding boxes object detection Small target detection YOLOv8
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Comparison of the Minimum Bounding Rectangle and Minimum Circumscribed Ellipse of Rain Cells from TRMM
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作者 Hongke CAI Yaqin MAO +2 位作者 Xuanhao ZHU Yunfei FU Renjun ZHOU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第3期391-406,共16页
Based on the TRMM dataset, this paper compares the applicability of the improved MCE(minimum circumscribed ellipse), MBR(minimum bounding rectangle), and DIA(direct indexing area) methods for rain cell fitting. These ... Based on the TRMM dataset, this paper compares the applicability of the improved MCE(minimum circumscribed ellipse), MBR(minimum bounding rectangle), and DIA(direct indexing area) methods for rain cell fitting. These three methods can reflect the geometric characteristics of clouds and apply geometric parameters to estimate the real dimensions of rain cells. The MCE method shows a major advantage in identifying the circumference of rain cells. The circumference of rain cells identified by MCE in most samples is smaller than that identified by DIA and MBR, and more similar to the observed rain cells. The area of rain cells identified by MBR is relatively robust. For rain cells composed of many pixels(N> 20), the overall performance is better than that of MCE, but the contribution of MBR to the best identification results,which have the shortest circumference and the smallest area, is less than that of MCE. The DIA method is best suited to small rain cells with a circumference of less than 100 km and an area of less than 120 km^(2), but the overall performance is mediocre. The MCE method tends to achieve the highest success at any angle, whereas there are fewer “best identification”results from DIA or MBR and more of the worst ones in the along-track direction and cross-track direction. Through this comprehensive comparison, we conclude that MCE can obtain the best fitting results with the shortest circumference and the smallest area on behalf of the high filling effect for all sizes of rain cells. 展开更多
关键词 TRMM minimum bounding rectangle minimum circumscribed ellipse
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State Bounding在目标跟踪中的应用 被引量:1
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作者 赵兴录 魏麦成 《现代雷达》 CSCD 北大核心 1999年第6期33-38,共6页
本文把Bounding估计引入目标跟踪领域,提出一种用状态估计集几何中心作为目标滤波值的递推算法。该算法使用椭圆集来描述状态的不确定性并给和系统和观测噪声的界,以最小值椭圆作为更新准则。仿真结果给出了本算法与Kalm... 本文把Bounding估计引入目标跟踪领域,提出一种用状态估计集几何中心作为目标滤波值的递推算法。该算法使用椭圆集来描述状态的不确定性并给和系统和观测噪声的界,以最小值椭圆作为更新准则。仿真结果给出了本算法与Kalman滤波算法的性能比较以及界内噪声分布不同时跟踪性能的差别。 展开更多
关键词 目标跟踪 bounding估计 滤波算法 状态估计
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基于无线传感器离散网络模型的Bounding Box定位算法研究
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作者 曾振东 《计算机应用与软件》 CSCD 北大核心 2013年第12期194-197,257,共5页
Bounding Box算法是一种典型的基于离散网络模型的无线传感器网络节点定位算法。针对Bounding Box算法定位误差大、覆盖率低的缺点,提出一种采用虚拟锚节点策略的改进定位算法。首先未知节点利用其通信范围内的锚节点进行定位;其次,已... Bounding Box算法是一种典型的基于离散网络模型的无线传感器网络节点定位算法。针对Bounding Box算法定位误差大、覆盖率低的缺点,提出一种采用虚拟锚节点策略的改进定位算法。首先未知节点利用其通信范围内的锚节点进行定位;其次,已定位的节点根据升级策略有选择性的升级为虚拟锚节点;最后,无法定位的节点利用虚拟锚节点实现定位。另外,在离散网络模型的基础上,通过建立双半径网络节点模型从而进一步约束了未知节点的位置。理论分析及仿真结果均表明,该算法在显著提高定位覆盖率的同时,有效地提高了定位精度。 展开更多
关键词 无线传感器网络 定位 bounding Box算法 离散网络 虚拟锚节点
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一种基于虚拟锚节点策略改进的Bounding Box定位算法
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作者 周莹 《电子器件》 CAS 北大核心 2014年第2期332-336,共5页
针对Bounding Box算法定位误差大、覆盖率低的缺点,提出了一种采用虚拟锚节点策略的改进定位算法。首先未知节点利用其通信范围内的锚节点进行定位;其次,已定位的节点根据升级策略有选择性的升级为虚拟锚节点;最后,无法定位的节点利用... 针对Bounding Box算法定位误差大、覆盖率低的缺点,提出了一种采用虚拟锚节点策略的改进定位算法。首先未知节点利用其通信范围内的锚节点进行定位;其次,已定位的节点根据升级策略有选择性的升级为虚拟锚节点;最后,无法定位的节点利用虚拟锚节点实现定位。另外,在离散网络模型的基础上,通过建立双半径网络节点模型从而进一步约束了未知节点的位置。理论分析及仿真结果均表明,该算法在显著提高定位覆盖率的同时,有效地提高了定位精度。 展开更多
关键词 无线传感器网络 定位 bounding Box算法 离散网络 虚拟锚节点
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State Bounding跟踪机动目标研究
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作者 赵兴录 《空军工程大学学报(自然科学版)》 CSCD 2000年第2期40-43,共4页
提出一种用 State Bounding估计跟踪机动目标的算法。用预测集、观测集中心距检测目标机动 ,修正系统噪声集尺寸适应目标机动 ,很好地解决了用 state Bounding估计跟踪机动目标问题。模拟结果表明本算法与相应的 kalman滤波器的性能相比 。
关键词 目标跟踪 bounding估计 滤波算法
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Helicopter maritime search area planning based on a minimum bounding rectangle and K-means clustering 被引量:3
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作者 Peisen XIONG Hu LIUa +3 位作者 Yongliang TIAN Zikun CHEN Bin WANG Hao YANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2021年第2期554-562,共9页
Helicopters are widely used in maritime Search and Rescue(SAR) missions. To ensure the success of SAR missions, search areas need to be carefully planned. With the development of computer technology and weather foreca... Helicopters are widely used in maritime Search and Rescue(SAR) missions. To ensure the success of SAR missions, search areas need to be carefully planned. With the development of computer technology and weather forecast technology, the survivors’ drift trajectories can be predicted more precisely, which strongly supports the planning of search areas for the rescue helicopter. However, the methods used to determine the search area based on the predicted drift trajectories are mainly derived from the continuous expansion of the area with the highest Probability of Containment(POC), which may lead to local optimal solutions and a decrease in the Probability of Success(POS), especially when there are several subareas with a high POC. To address this problem, this paper proposes a method based on a Minimum Bounding Rectangle and Kmeans clustering(MBRK). A silhouette coefficient is adopted to analyze the distribution of the survivors’ probable locations, which are divided into multiple clusters with K-means clustering. Then,probability maps are generated based on the minimum bounding rectangle of each cluster. By adding or subtracting one row or column of cells or shifting the planned search area, 12 search methods are used to generate the optimal search area starting from the cell with the highest POC in each probability map. Taking a real case as an example, the simulation experiment results show that the POS values obtained by the MBRK method are higher than those obtained by other methods,which proves that the MBRK method can effectively support the planning of search areas and that K-means clustering improves the POS of search plans. 展开更多
关键词 K-means clustering Minimum bounding rectangle Mission planning Probability map Search and rescue
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A New Relay Attack on Distance Bounding Protocols and Its Solution with Time-Stamped Authentication for RFID 被引量:2
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作者 WEI Guoheng ZHANG Huanguo WANG Ya 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2016年第1期37-46,共10页
Relay attack is one of the most threatening challenges against radio frequency identification(RFID) now. Distance bounding protocols have been introduced to thwart relay attacks. They form a family of challenge-resp... Relay attack is one of the most threatening challenges against radio frequency identification(RFID) now. Distance bounding protocols have been introduced to thwart relay attacks. They form a family of challenge-response authentication protocols and confirm the round-trip time at the Rapid Bit Exchange phase. They enable a reader to authenticate and to establish an upper bound on the physical distance to an entrusted tag. We design an effective attack against a family of such protocols to launch the spoofing attacks within effective distance successfully, which demonstrates that existing protocols cannot eliminate such attacks completely. The thesis proposes a new program with time- stamping verification to correct the defect and verify the effectiveness. 展开更多
关键词 radio frequency identification(RFID) distance bounding protocol relay attack rapid bit exchange
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Collision detection of virtual plant based on bounding volume hierarchy: A case study on virtual wheat 被引量:7
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作者 TANG Liang SONG Wei-guo +3 位作者 HOU Tian-cheng LIU Lei-lei CAO Wei-xing ZHU Yan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第2期306-314,共9页
Visualization of simulated crop growth and development is of significant interest to crop research and production. This study aims to address the phenomenon of organs cross-drawing by developing a method of collision ... Visualization of simulated crop growth and development is of significant interest to crop research and production. This study aims to address the phenomenon of organs cross-drawing by developing a method of collision detection for improving vivid 3D visualizations of virtual wheat crops. First, the triangular data of leaves are generated with the tessellation of non-uniform rational B-splines surfaces. Second, the bounding volumes(BVs) and bounding volume hierarchies(BVHs) of leaves are constructed based on the leaf morphological characteristics and the collision detection of two leaves are performed using the Separating Axis Theorem. Third, the detecting effect of the above method is compared with the methods of traditional BVHs, Axis-Aligned Bounding Box(AABB) tree, and Oriented Bounding Box(OBB) tree. Finally, the BVs of other organs(ear, stem, and leaf sheath) in virtual wheat plant are constructed based on their geometric morphology, and the collision detections are conducted at the organ, individual and population scales. The results indicate that the collision detection method developed in this study can accurately detect collisions between organs, especially at the plant canopy level with high collision frequency. This collision detection-based virtual crop visualization method could reduce the phenomenon of organs cross-drawing effectively and enhance the reality of visualizations. 展开更多
关键词 wheat collision detection bounding volume hierarchy virtual plant morphology
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Improved shape hardening function for bounding surface model for cohesive soils 被引量:1
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作者 Andrés Nieto-Leal Victor N.Kaliakin 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2014年第4期328-337,共10页
A shape hardening function is developed that improves the predictive capabilities of the generalized bounding surface model for cohesive soils, especially when applied to overconsolidated specimens. This improvement i... A shape hardening function is developed that improves the predictive capabilities of the generalized bounding surface model for cohesive soils, especially when applied to overconsolidated specimens. This improvement is realized without any changes to the simple elliptical shape of the bounding surface, and actually reduces the number of parameters associated with the model by one. 展开更多
关键词 Constitutive model bounding surface plasticity Shape hardening function Clay
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The bounding-surfaces record of a barrier spit from Huangqihai Lake,North China:implications for coastal barrier boundary hierarchy
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作者 单新 于兴河 +3 位作者 Peter D.CLIFT 王天意 谭程鹏 金丽娜 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第5期1097-1105,共9页
Ground-penetrating radar and trenching studies of a barrier spit on the north shore of Huangqihai Lake were made,that reveal important implications for the coastal washover barrier boundary hierarchy and interpretatio... Ground-penetrating radar and trenching studies of a barrier spit on the north shore of Huangqihai Lake were made,that reveal important implications for the coastal washover barrier boundary hierarchy and interpretations of this depositional record.A four-fold hierarchy bounding-surface model,representing different levels of impact and genesis,is defined.Each level of the hierarchy is enclosed by a distinct kind of surface characterized by different ground-penetrating radar reflection features,sedimentary characteristics(color,grain size,sorting,rounding and sedimentary structures) and origin.We suggest that this hierarchical model can be applied to any coastal washover barrier deposits. 展开更多
关键词 coastal barrier boundary hierarchy washover deposits ground-penetrating radar bounding surface Huangqihai Lake
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Visibility Culling Algorithm with Hierarchical Adaptive Bounding Setting
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作者 郑福仁 李凤霞 +1 位作者 战守义 杨兵 《Journal of Beijing Institute of Technology》 EI CAS 2006年第1期76-80,共5页
Hierarchical adaptive bounding setting (HABS), a novel algorithm to reduce potentially visible set, is designed to be Used for various geometry shape character in complex simulation scene to greatly improve geometry... Hierarchical adaptive bounding setting (HABS), a novel algorithm to reduce potentially visible set, is designed to be Used for various geometry shape character in complex simulation scene to greatly improve geometry spatial storage precision. A spatial hierarchy tree is used to represent the topology of the model, and then the visibility geometry set from the viewpoint is determined by processing the hierarchy tree and frustum detection. In this process, HABS improves the viewpoint-to-region visibility detection efficiently. The algorithm is well-suited for complex models whose shape characters are various. 展开更多
关键词 HABS visibility culling OCTREE adaptive bounding frustum
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Piezoelectrically Actuated Biomimetic Self-Contained Quadruped Bounding Robot
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作者 Thanhtam Ho Sangyoon Lee 《Journal of Bionic Engineering》 SCIE EI CSCD 2009年第1期29-36,共8页
This paper presents the development of a mesoscale self-contained quadruped mobile robot that employs two pieces of piezocomposite actuators for the bounding locomotion.The design of the robot leg is inspired by legge... This paper presents the development of a mesoscale self-contained quadruped mobile robot that employs two pieces of piezocomposite actuators for the bounding locomotion.The design of the robot leg is inspired by legged insects and animals, and the biomimetic concept is implemented in the robot in a simplified form,such that each leg of the robot has only one degree of freedom.The lack of degree of freedom is compensated by a slope of the robot frame relative to the horizontal plane.For the implementation of the self-contained mobile robot,a small power supply circuit is designed and installed on the robot.Experimental results show that the robot can locomote at about 50 mm·s^(-1)with the circuit on board,which can be considered as a significant step toward the goal of building an autonomous legged robot actuated by piezoelectric actuators. 展开更多
关键词 piezoelectric actuator quadruped robot bounding locomotion self-contained legged robot
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Bounding box based on probability density for the pedestrian tracking
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作者 Jaehyun So Hernsoo Hahn Youngjun Han 《Journal of Measurement Science and Instrumentation》 CAS 2012年第4期333-335,共3页
This paper proposes a pedestrian tracking approach using bounding box based on probability densities.It is generally a difficult task to track features like corner points in outdoor images due to complex environment.T... This paper proposes a pedestrian tracking approach using bounding box based on probability densities.It is generally a difficult task to track features like corner points in outdoor images due to complex environment.To solve this problem,the feature points are projected along X and Y direction separately,and a histogram is constructed for each projection,with horizontal axis as positions and vertical axis as the number of feature points that lie on each position.Finally,the vertical axis is normalized for expression as probability.After histogram is constructed,the probability of each feature point is checked with a threshold.A feature point will be ignored if its probability is lower than a threshold,while the remaining feature points are grouped,based on which a bounding box is made.Kanade-Lucas Tomasi(KLT)algorithm is adopted as the tracking algorithm because it is able to track local features in images robustly.The efficiency of the tracking results using this method is verified in real environment test. 展开更多
关键词 pedestrian tracking probability density bounding box Kanade-Lucas Tomasi(KLT) feature tracker
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Shortest Alternate Path Discovery through Recursive Bounding Box Pruning
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作者 Rajendra S. Parmar Bhushan H. Trivedi 《Journal of Transportation Technologies》 2017年第2期167-180,共14页
Congestion is a dynamic phenomenon and hence efficiently computing alternate shortest route can only help expedite decongestion. This research is aimed to efficiently compute shortest path for road traffic network so ... Congestion is a dynamic phenomenon and hence efficiently computing alternate shortest route can only help expedite decongestion. This research is aimed to efficiently compute shortest path for road traffic network so that congestion can be eased resulting in reduced CO2 emission and improved economy. Congestion detection is achieved after evaluating road capacity and road occupancy. Congestion index, a ratio of road occupancy to road capacity is computed, congestion index higher than 0.6 necessitates computation of alternate shortest route. Various algorithms offer shortest alternate route. The paper discusses minimization of graph based by removing redundant nodes which don’t play a role in computation of shortest path. The proposal is based on continuous definition of a bounding box every time a next neighboring node is considered. This reduces maximum number of contentious nodes repeatedly and optimizes the network. The algorithm is deployed from both the ends sequentially to ensure zero error and validate the shortest path discovery. While discovering shortest path, the algorithm also offers an array of shortest path in ascending order of the path length. However, vehicular traffic exhibits network duality viz. static and dynamic network graphs. Shortest route for static distance graph is pre-computed and stored for look-up, alternate shortest path based on assignment of congestion levels to edge weights is triggered by congestion index. The research also supports directed graphs to address traffic rules for lanes having unidirectional and bidirectional traffic. 展开更多
关键词 bounding Box PRUNING Geometric Containers Shortest ALTERNATE PATH Shortest PATH Vehicular Traffic Vehicular CONGESTION DETECTION SYSTEM Vehicular CONGESTION DETECTION SYSTEM
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Bounding Inequalities for Eigenvalues of Principal Submatrices
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作者 Achiya Dax 《Advances in Linear Algebra & Matrix Theory》 2019年第2期21-34,共14页
Ky Fan trace theorems and the interlacing theorems of Cauchy and Poincaré are important observations that characterize Hermitian matrices. In this note, we introduce a new type of inequalities which extend these ... Ky Fan trace theorems and the interlacing theorems of Cauchy and Poincaré are important observations that characterize Hermitian matrices. In this note, we introduce a new type of inequalities which extend these theorems. The new inequalities are obtained from the old ones by replacing eigenvalues and diagonal entries with their moduli. This modification yields effective bounding inequalities which are valid on a larger range of matrices. 展开更多
关键词 Cauchy INTERLACING THEOREM POINCARÉ INTERLACING THEOREM Ky Fan Trace Theorems NON-HERMITIAN MATRICES Normal MATRICES bounding INEQUALITIES
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Ellipsoidal bounding set-membership identification approach for robust fault diagnosis with application to mobile robots 被引量:7
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作者 Bo Zhou Kun Qian +1 位作者 Xudong Ma Xianzhong Dai 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第5期986-995,共10页
A robust fault diagnosis approach is developed by incorporating a set-membership identification (SMI) method. A class of systems with linear models in the form of fault related parameters is investigated, with model u... A robust fault diagnosis approach is developed by incorporating a set-membership identification (SMI) method. A class of systems with linear models in the form of fault related parameters is investigated, with model uncertainties and parameter variations taken into account explicitly and treated as bounded errors. An ellipsoid bounding set-membership identification algorithm is proposed to propagate bounded uncertainties rigorously and the guaranteed feasible set of faults parameters enveloping true parameter values is given. Faults arised from abrupt parameter variations can be detected and isolated on-line by consistency check between predicted and observed parameter sets obtained in the identification procedure. The proposed approach provides the improved robustness with its ability to distinguish real faults from model uncertainties, which comes with the inherent guaranteed robustness of the set-membership framework. Efforts are also made in this work to balance between conservativeness and computation complexity of the overall algorithm. Simulation results for the mobile robot with several slipping faults scenarios demonstrate the correctness of the proposed approach for faults detection and isolation (FDI). 展开更多
关键词 set-membership identification fault diagnosis fault detection and isolation (FDI) bounded error mobile robot
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Transferring and Bounding Single Photon in Waveguide Controlled by Quantum Node Based on Atomic Ensemble
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作者 LU Jing DONG Hui KUANG Le-Man 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第9期500-506,共7页
We study the scattering process of photons confined in a one-dimensional optical waveguide by a laser controlled atomic ensemble. The investigation leads to an alternative setup of quantum node controlling the coheren... We study the scattering process of photons confined in a one-dimensional optical waveguide by a laser controlled atomic ensemble. The investigation leads to an alternative setup of quantum node controlling the coherent transfer of single photon in such one dimensional continuum. To exactly solve the effective scattering equations by using the discrete coordinate approach, we simulate the linear waveguide as a coupled resonator array at the high energy limit. We generally calculate the transmission eoet^cients and its vanishing at resonance reflects the good controllability of our scheme. We also show that there exist two bound states to describe the localize photons around the cavity. 展开更多
关键词 one-dimensional waveguide single photon bound states
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