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Research on novel multi-layer and multi-polarized slot-coupling planar antenna array
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作者 ZhangHou Wu Wenzhou Wang Jian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第2期297-303,共7页
A novel multi-layer planar antenna array to achieve multi-polarized radiation is developed. U-shaped coupling slots are embedded in the ground plane to extend the bandwidth. The phase relation between adjacent element... A novel multi-layer planar antenna array to achieve multi-polarized radiation is developed. U-shaped coupling slots are embedded in the ground plane to extend the bandwidth. The phase relation between adjacent elements in the radiation field is analyzed when adjacent elements are fed in opposite phase. Return loss and radiation pattern are measured for a 16-element antenna array at 12.5 GHz. The radiation pattern shows a good agreement with the calculated one in the shape of the main beam. The return-loss of the proposed antenna array is less than -20 dB in the 12.5 GHz frequency band (12.25-12.75 GHz). Because of two feed ports the antenna can transmit arbitrary elliptic polarized waves if the two feed ports have different amplitude and phase. The main factors such as element spacing, substrate medium and manufacturing imperfection are analyzed and the corresponding conclusions are presented. 展开更多
关键词 planar antenna multi-polarized slot-coupling cross polarization
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Construction of enhanced multi-polarization and high performance electromagnetic wave absorption by self-growing ZnFe_(2)O_(4)on Cu_(9)S_(5)
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作者 Wenxiong Chen Honglong Xing 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第8期1922-1934,共13页
The development of 3D structural composites with electromagnetic(EM)wave absorption could attenuate EM waves.Herein,magnetized flower-like Cu_(9)S_(5)/ZnFe_(2)O_(4)composites were fabricated through a multistep hydrot... The development of 3D structural composites with electromagnetic(EM)wave absorption could attenuate EM waves.Herein,magnetized flower-like Cu_(9)S_(5)/ZnFe_(2)O_(4)composites were fabricated through a multistep hydrothermal method.The crystallographic and surface phase chemical information,morphological structure,and magnetic and EM parameters of the composites were analyzed.The prepared Cu_(9)S_(5)/ZnFe_(2)O_(4)composites have multiple loss paths for EM waves and present an overall 3D flower-like structure.The Cu_(9)S_(5)/ZnFe_(2)O_(4)composites exhibit a minimum reflection loss of-54.38 dB and a broad effective absorption bandwidth of 5.92 GHz.Through magnetization,ZnFe_(2)O_(4)particles are self-assembled and grown on the surfaces of Cu_(9)S_(5).Such a modification is conducive to the generation of additional cross-linking contact sites and the effective introduction of a large number of phase interfaces,crystalline defects,special three-dimensional flower-like structures,and magneto-electrical coupling loss effects.Moreover,the synergistic effect of multiple loss strategies effectively improves EM wave absorption by the material.This work can provide a strategy for the use of magnetizationmodified sulfide composite functional materials in EM wave absorption. 展开更多
关键词 self-assembled material electromagnetic wave absorption enhanced multi-polarization effect Cu_(9)S_(5)/ZnFe_(2)O_(4)composites radar cross-section
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The internal COF features in Dome A of Antarctica revealed by multi-polarization-plane RES 被引量:5
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作者 王帮兵 田钢 +1 位作者 崔祥斌 张向培 《Applied Geophysics》 SCIE CSCD 2008年第3期230-237,共8页
The ice exceeding one million years old has significant meaning for verifying and interpreting the middle Pleistocene transition (MPT) and the relationship between greenhouse gas and climate change. The region near ... The ice exceeding one million years old has significant meaning for verifying and interpreting the middle Pleistocene transition (MPT) and the relationship between greenhouse gas and climate change. The region near Dome A in Antarctica satisfies the conditions for obtaining million-years-old ice since it has low temperatures and low accumulation rates. We analyze the corresponding relation between radar wave features and the crystal orientation fabric (COF) types based on the results of multi-polarization plane radio echo sounding (RES). The results show that, even in the summit of the ice sheet, the COF type is not perfect, but is an elongated single-pole COF. Principal-axis-orientation differences of the COF among the different periods exist and reveal that the ice flow orientations are not constant but deviate clockwise with the increasing depth. This may be related to the adjacent basal valley or both height and position changes of the summit during the glacial-interglacial periods. 展开更多
关键词 Crystal orientation fabric (COF) radio echo sounding (RES) multi-polarization plane technique ice flow orientation
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安装制作工具Inno Setup及其在VC++工程中的应用 被引量:3
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作者 宋玉春 许伦辉 刘瑶 《韶关学院学报》 2006年第6期25-27,共3页
VC++工程开发完成时必须制作安装文件,Inno Setup是一个免费的、公开源码的安装制作工具,同时提供了相应的使用方法.文中针对Inno Setup打包VC++工程在安装VC++系统支持文件、ODBC数据源配置、Ac-tiveX控件注册等方面的问题,进行了详细... VC++工程开发完成时必须制作安装文件,Inno Setup是一个免费的、公开源码的安装制作工具,同时提供了相应的使用方法.文中针对Inno Setup打包VC++工程在安装VC++系统支持文件、ODBC数据源配置、Ac-tiveX控件注册等方面的问题,进行了详细研究并给出了解决方法. 展开更多
关键词 Inno setup 安装制作 VC++
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基于Inno Setup的Delphi应用程序的发布技巧 被引量:1
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作者 郑江花 秦立刚 张霞 《信息技术与信息化》 2008年第3期76-77,共2页
本文介绍安装制作工具Inno Setup为Delphi应用软件开发相应安装程序,特别对自动安装动态配置BDE数据库引擎、动态配置ODBC数据源、ActiveX控件注册等方面的问题进行了综合研究,并给出了一种解决方法,供软件开发者参考。
关键词 Inno setup DELPHI BDE ODBC
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单机序列相关Setup最小化最大拖期算法
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作者 罗小川 王成恩 《计算机应用》 CSCD 北大核心 2005年第8期1829-1832,共4页
研究了一个具有序列相关Setup带交货期的单机调度NP问题,优化目标是最小化最大拖期。提出了一个求解该问题的分枝定界枚举算法,其中包括确定问题上界和下界的方法,以及两条优势规则。计算实验证明了本文提出算法的有效性。
关键词 序列相关setup 交货期 最大拖期 分枝定界 单机调度
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序列相关Setup单机调度的最小化最大拖期分枝定界算法
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作者 罗小川 刘长勇 +1 位作者 刘晓 王成恩 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2005年第10期938-941,共4页
研究了具有序列相关Setup带交货期的单机调度NP问题,优化目标是最小化最大拖期.通过松弛子路径连通约束,提出了基于AP算法的下界方法.在算法下界的基础上,基于下界解建立了以改进Karp-Steel补偿启发式方法构成的上界构造方法.发现了反... 研究了具有序列相关Setup带交货期的单机调度NP问题,优化目标是最小化最大拖期.通过松弛子路径连通约束,提出了基于AP算法的下界方法.在算法下界的基础上,基于下界解建立了以改进Karp-Steel补偿启发式方法构成的上界构造方法.发现了反映问题特性的两条优势规则.最后依托Ragatz提出的分枝定界算法框架,引入上界和下界方法,以及两条优势规则,形成了求解该问题的分枝定界枚举算法.通过计算实验证明了算法的有效性. 展开更多
关键词 序列相关setup 交货期 最大拖期 单机调度 分枝定界
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实例阐述Setup Factory对软件进行打包发布
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作者 崔晓阳 《农业网络信息》 2007年第8期33-35,共3页
基于中华农业科教基金会信息管理系统打包发布文件(EXE)的制作经验,本文结合具体的实例对Setup Factory软件的使用进行简单的介绍,包括流程、设置和生成EXE可执行性文件等。
关键词 EXE setup FACTORY
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Mean water level setup/setdown in the inlet-lagoon system induced by tidal action—a case study of Xincun Inlet,Hainan Island in China 被引量:7
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作者 GONG Wenping SHEN Jian WANG Daoru 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2008年第5期63-80,共18页
With the tides propagating from the open sea to the lagoon, the mean water level (MWL) in the inlet and lagoon becomes different from that at the open sea, and a setup/setdown is generated. The change of MWL (setup... With the tides propagating from the open sea to the lagoon, the mean water level (MWL) in the inlet and lagoon becomes different from that at the open sea, and a setup/setdown is generated. The change of MWL (setup/setdown) in the system imposes a great impact on regulating the development of tidal marshes, on determining the long-term water level for harbor maintenance, on the planning for the water front development with the flood control for the possible inundation, and on the interpretation of the historical sea level change when using tidal marsh peat deposits in the lagoon as the indicator for open sea' s sea level. In this case study on the mechanisms which control the setup/setdown in Xincun Inlet, Hainan in China, the 2-D barotropic mode of Eulerian - Lagrangian CIRCulation (ELCIRC) model was utilized. After model calibration and verification, a series of numerical experiments were conducted to examine the effects of bottom friction and advection terms, wetting and drying of intertidal areas, bathymetry and boundary conditions on the setup/setdown in the system. The modeling results show that setup occurs over the inlet and lagoon areas with an order of one tenth of the tide range at the entrance. The larger the bottom friction is, a larger setup is generated. Without the advection term, the setup is reduced clue to a decrease of water level gradient to compensate for the disappearance of the advection term. Even without overtides, a setup can still be developed in the system. Sea level rise and dredging in the inlet and tidal channel can cause a decrease of setup in the system, whereas shoaling of the system can increase the setup. The uniqueness of the Xincun Inlet with respect to MWL change is that there is no evident setdown in the inlet, which can be attributed to the complex geometry and bathymetry associated with the inlet system. 展开更多
关键词 tidal inlet water level setup/setdown ELCIRC Hainan Island
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A Comparative Study of Numerical Models for Wave Propagation and Setup on Steep Coral Reefs 被引量:4
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作者 ZHANG Shan-ju ZHU Liang-sheng ZOU Kai 《China Ocean Engineering》 SCIE EI CSCD 2019年第4期424-435,共12页
Complex factors including steep slopes, intense wave breaking, large bottom friction and remarkable wave setup should be considered while studying wave propagation over coral reefs, and how to simulate wave propagatio... Complex factors including steep slopes, intense wave breaking, large bottom friction and remarkable wave setup should be considered while studying wave propagation over coral reefs, and how to simulate wave propagation and setup on coral reefs efficiently has become a primary focus. Several wave models can be used on coral reefs as have been published, but further testing and comparison of the reliability and applicability of these models are needed. A comparative study of four numerical wave models (i.e., FUNWAVE-TVD, Coulwave, NHWAVE and ZZL18) is carried out in this paper. These models’ governing equations and numerical methods are compared and analyzed firstly to obtain their differences and connections;then the simulation effects of the four wave models are tested in four representative laboratory experiments. The results show that all four models can reasonably predict the spectrum transformation. Coulwave, NHWAVE and ZZL18 can predict the wave height variation more accurately;Coulwave and FUNWAVE-TVD tend to underestimate wave setup on the reef top induced by spilling breaker, while NHWAVE and ZZL18 can predict wave setup relatively accurately for all types of breakers;NHWAVE and ZZL18 can predict wave reflection by steep reef slope more accurately. This study can provide evidence for choosing suitable models for practical engineering or establishing new models. 展开更多
关键词 CORAL REEFS STEEP slope BOUSSINESQ equations WAVE propagation and setup WAVE breaking numerical simulation comparative study
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Measuring Radiotherapy Setup Errors in IMRT Treated Head and Neck Cancer Patients Requiring Bilateral Neck Irradiation, NCI-Egypt Experience 被引量:3
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作者 May G. Ashour Tarek H. Shouman +3 位作者 Ashraf H. Hassouna Reem M. Emad El Din Maha H. Mokhtar Mohamed A. Khalil 《Journal of Cancer Therapy》 2017年第13期1160-1168,共9页
Objective: We aim to quantify the magnitude of setup errors in intensity-modulated radiotherapy (IMRT) treated Head and Neck cancer patients and recommend appropriate PTV margin. Methods: 60 patients with head and nec... Objective: We aim to quantify the magnitude of setup errors in intensity-modulated radiotherapy (IMRT) treated Head and Neck cancer patients and recommend appropriate PTV margin. Methods: 60 patients with head and neck cancer required bilateral neck irradiation were planned and treated by simultaneous integrated boost IMRT technique either treated radically or postoperative. Patients undergoing image-guided radiotherapy (IGRT) each with once weekly scheduled cone beam computed tomography (CBCT). The 3D displacements, systematic and random errors were calculated. The appropriate PTV expansion was determined using Van Herk’s formula. Results: Mean 3D displacement was 0.16 cm in the vertical direction, 0.14 cm in the horizontal direction and 0.16 cm in the longitudinal direction. Conclusion: Use of weekly CBCT allows the planning target volume (PTV) expansion to be reduced according to our setup. The appropriate clinical target volume (CTV)-PTV margin for our institute is 0.30 cm, 0.38 cm, and 0.33 cm in the horizontal, vertical, and longitudinal directions, respectively. 展开更多
关键词 IMRT CBCT setup Errors Head and NECK
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A Compact Setup of Saturated Absorption Spectroscopy for Diode Laser Frequency Stabilization 被引量:3
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作者 ZHANG Xian HUANG Kai-Kai +3 位作者 XU Hao XU Zhou-Xiang LI Nan LU Xuan-Hui 《Chinese Physics Letters》 SCIE CAS CSCD 2012年第7期114-117,共4页
A novel setup of saturated absorption spectroscopy (SAS) is presented.It is based on laser reflections at surfaces of a sample vapor cell.It only needs one cell and one photodiode and is more compact than conventional... A novel setup of saturated absorption spectroscopy (SAS) is presented.It is based on laser reflections at surfaces of a sample vapor cell.It only needs one cell and one photodiode and is more compact than conventional setups of SAS.Its spectrum is similar to a conventional SAS.The frequency stabilization performance of an external-cavity diode laser with this setup is investigated.A frequency stability of 1.1 × 10^(-11) is achieved at an averaging time of 60s in the Allen variance measurements. 展开更多
关键词 setup COMPACT STABILIZATION
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Single Machine Scheduling with Time-Dependent Learning Effect and Non-Linear Past-Sequence-Dependent Setup Times 被引量:1
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作者 Yuling Yeh Chinyao Low Wen-Yi Lin 《Journal of Applied Mathematics and Physics》 2015年第1期10-15,共6页
This paper studies a single machine scheduling problem with time-dependent learning and setup times. Time-dependent learning means that the actual processing time of a job is a function of the sum of the normal proces... This paper studies a single machine scheduling problem with time-dependent learning and setup times. Time-dependent learning means that the actual processing time of a job is a function of the sum of the normal processing times of the jobs already scheduled. The setup time of a job is proportional to the length of the already processed jobs, that is, past-sequence-dependent (psd) setup time. We show that the addressed problem remains polynomially solvable for the objectives, i.e., minimization of the total completion time and minimization of the total weighted completion time. We also show that the smallest processing time (SPT) rule provides the optimum sequence for the addressed problem. 展开更多
关键词 Scheduling TIME-DEPENDENT Learning setup TIME Past-Sequence-Dependent Total COMPLETION TIME
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Psychosomatic symptoms affect radiotherapy setup errors in early breast cancer patients 被引量:1
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作者 Yi He Chang Gao +2 位作者 Ying Pang Jixiang Chen Lili Tang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2021年第3期323-330,共8页
Objective: To examine the trajectory of psychosomatic symptoms and to explore the impact of psychosomatic symptoms on setup error in patients undergoing breast cancer radiotherapy.Methods: A total of 102 patients with... Objective: To examine the trajectory of psychosomatic symptoms and to explore the impact of psychosomatic symptoms on setup error in patients undergoing breast cancer radiotherapy.Methods: A total of 102 patients with early breast cancer who received initial radiotherapy were consecutively recruited. The M.D. Anderson Symptom Inventory(MDASI) and three different anxiety scales, i.e., the Self-Rating Anxiety Scale(SAS), State-Trait Anxiety Inventory(STAI), and Anxiety Sensitivity Index(ASI), were used in this study. The radiotherapy setup errors were measured in millimetres by comparing the real-time isocratic verification film during radiotherapy with the digitally reconstructed radiograph(DRR). Patients completed the assessment at three time points: before the initial radiotherapy(T1), before the middle radiotherapy(T2), and before the last radiotherapy(T3).Results: The SAS and STAI-State scores of breast cancer patients at T1 were significantly higher than those at T2 and T3(F=24.44, P<0.001;F=30.25, P<0.001). The core symptoms of MDASI were positively correlated with anxiety severity. The setup errors of patients with high SAS scores were greater than those of patients with low anxiety levels at T1(Z=-2.01, P=0.044). We also found that higher SAS scores were associated with a higher risk of radiotherapy setup errors at T1(B=0.458, P<0.05).Conclusions: This study seeks to identify treatment-related psychosomatic symptoms and mitigate their impact on patients and treatment. Patients with early breast cancer experienced the highest level of anxiety before the initial radiotherapy, and then, anxiety levels declined. Patients with high somatic symptoms of anxiety may have a higher risk of radiotherapy setup errors. 展开更多
关键词 Psychosomatic symptom ANXIETY setup error RADIOTHERAPY breast cancer
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No-Wait Flowshops to Minimize Total Tardiness with Setup Times 被引量:1
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作者 Tariq Aldowaisan Ali Allahverdi 《Intelligent Control and Automation》 2015年第1期38-44,共7页
The m-machine no-wait flowshop scheduling problem is addressed where setup times are treated as separate from processing times. The objective is to minimize total tardiness. Different dispatching rules have been inves... The m-machine no-wait flowshop scheduling problem is addressed where setup times are treated as separate from processing times. The objective is to minimize total tardiness. Different dispatching rules have been investigated and three were found to be superior. Two heuristics, a simulated annealing (SA) and a genetic algorithm (GA), have been proposed by using the best performing dispatching rule as the initial solution for SA, and the three superior dispatching rules as part of the initial population for GA. Moreover, improved versions of SA and GA are proposed using an insertion algorithm. Extensive computational experiments reveal that the improved versions of SA and GA perform about 95% better than SA and GA. The improved version of GA outperforms the improved version of SA by about 3.5%. 展开更多
关键词 NO-WAIT FLOWSHOP Scheduling setup TIMES Total TARDINESS Simulated Annealing GENETIC Algorithm
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Scheduling a three-machine no-wait flowshop with separated setup time 被引量:1
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作者 常俊林 邵惠鹤 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2006年第2期206-210,共5页
In many practical flowshop production environments, there is no intermediate storage space available to keep partially completed jobs between any two machines. The workflow has to be continuous, implying that the no-w... In many practical flowshop production environments, there is no intermediate storage space available to keep partially completed jobs between any two machines. The workflow has to be continuous, implying that the no-wait conditions must be abided, which is typical in steel and plastic production. We discuss the three-machine no-wait flowshop scheduling problem where the setup times are considered as separated from processing times and sequence independent. The scheduling goal is to minimize the total flowtime. An optimal property and two heuristic algorithms for this problem are proposed. Evaluated over a large number of problems, the proposed heuristics are found that they can yield good solutions effectively with low computational complexity, and have more obvious advantage for the large size problem compared with the existing one. 展开更多
关键词 three-machine flowshop setup time NO-WAIT total flow time
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Multi-polarization reconstruction from compact polarimetry based on modified four-component scattering decomposition 被引量:1
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作者 Junjun Yin Jian Yang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第3期399-410,共12页
An improved algorithm for multi-polarization reconstruction from compact polarimetry (CP) is proposed. According to two fundamental assumptions in compact polarimetric reconstruction, two improvements are proposed. ... An improved algorithm for multi-polarization reconstruction from compact polarimetry (CP) is proposed. According to two fundamental assumptions in compact polarimetric reconstruction, two improvements are proposed. Firstly, the four-component model-based decomposition algorithm is modified with a new volume scattering model. The decomposed helix scattering component is then used to deal with the non-reflection symmetry condition in compact polarimetric measurements. Using the decomposed power and considering the scattering mechanism of each component, an average relationship between copolarized and crosspolarized channels is developed over the original polarization state extrapolation model. E-SAR polarimetric data acquired over the Oberpfaffenhofen area and JPL/AIRSAR polarimetric data acquired over San Francisco are used for verification, and good reconstruction results are obtained, demonstrating the effectiveness of the proposed algorithm. 展开更多
关键词 polarimetric synthetic aperture radar (SAR) target decomposition compact polarimetry (CP) multi-polarization reconstruction.
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胸部肿瘤螺旋断层放疗系统setup功能位置矫正与误差来源分析
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作者 徐士飞 冯欢 +2 位作者 刘海洋 胡杰 马露 《医学新知》 CAS 2022年第1期47-52,共6页
目的探讨螺旋断层放疗(helical tomotherapy,HT)系统setup功能矫正位置误差的作用并分析误差的来源。方法分析36例胸部肿瘤患者兆伏级计算机断层扫描图像信息,收集首次放疗常规复位和第二次放疗setup功能复位扫描的图像,并分别记录与千... 目的探讨螺旋断层放疗(helical tomotherapy,HT)系统setup功能矫正位置误差的作用并分析误差的来源。方法分析36例胸部肿瘤患者兆伏级计算机断层扫描图像信息,收集首次放疗常规复位和第二次放疗setup功能复位扫描的图像,并分别记录与千伏级计算机断层扫描图像配准的位置误差。比较2次复位误差间差异,构建重复测量混合线性回归模型分析可能的误差来源。结果除左右方向平移误差外,setup功能复位后误差均值总体上均小于首次复位,尤其在前后方向上,setup功能复位后误差显著小于首次复位(0.17±1.14 vs.5.04±2.43,P<0.001)。多因素分析发现,体质量指数(BMI)对胸部肿瘤前后方向平移误差和Roll旋转误差存在影响,回归系数β分别为0.191(P=0.001)和0.034(P=0.040)。此外,前后方向平移误差还受到分次剂量和治疗次数的影响。未发现性别、年龄和疾病类型对位置误差有明确影响。结论setup功能能够矫正位置误差,尤其前后方向平移误差。BMI、分次剂量和治疗次数影响胸部肿瘤放疗前后方向位置精准性。 展开更多
关键词 螺旋断层放疗系统 位置误差 setup功能 BMI
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Constitutive relationship of ionic polymer-metal composite and static response character of its cantilever setup to voltage 被引量:1
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作者 唐华平 聂拓 +3 位作者 唐运军 殷陈峰 唐春喜 王桥医 《Journal of Central South University of Technology》 EI 2008年第3期387-391,共5页
As a new ionic polymer-metal composite(IPMC) for artificial muscle,the mechanical performance parameters and the relationship between the deformation and the electrical parameters of the IPMC were studied. With the di... As a new ionic polymer-metal composite(IPMC) for artificial muscle,the mechanical performance parameters and the relationship between the deformation and the electrical parameters of the IPMC were studied. With the digital speckle correlation method,the constitutive relationship of the IPMC was confirmed. With non-contact photography measurement,a cantilever setup was designed to confirm the relationship between the deformation of the IPMC film and the applied voltage. The relationship curve of tip displacement of the IPMC cantilever setup vs the voltage was achieved. The results indicate that the IPMC is isotropic,its elastic modulus is 232 MPa and Poisson ratio is 0.163. The curve achieved from the test of the tip displacement of the IPMC cantilever setup shows that the tip displacement reaches the maximum when the stimulated voltage is 5 V. And the tip displacement descends largely when the frequency of the applied voltage is between 30 mHz and 100 mHz. 展开更多
关键词 constitutive relationship ionic polymer-metal composite(IPMC) cantilever setup static response
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Theoretical study on setup of expanded-base pile considering cavity contraction
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作者 齐昌广 刘干斌 +1 位作者 王艳 邓岳保 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第11期4355-4365,共11页
When an expanded-base pile is installed into ground, the cavity expansion associated with penetration of the enlarged pile base is followed by cavity contraction along the smaller-diameter pile shaft. In order to acco... When an expanded-base pile is installed into ground, the cavity expansion associated with penetration of the enlarged pile base is followed by cavity contraction along the smaller-diameter pile shaft. In order to account for the influence of cavity contraction on the change of bearing capacity of expanded-base pile, a theoretical calculation methodology, predicting the setup of expanded-base pile, was established by employing the cavity contraction theory to estimate the shaft resistance of expanded-base pile, and horizontal consolidation theory to predict the dissipation of excess pore pressure. Finally, the numerical solutions for the setup of expanded-base pile were obtained. The parametric study about the influence of cavity contraction on setup of expanded-base pile was carried out, while a field test was introduced. The parametric study shows that the decrements in radial pressure and the maximum pore water pressure after considering cavity contraction are increased as the expanded ratio(base diameter/shaft diameter) and rigidity index of soil are raised. The comparison between calculated and measured values shows that the calculated results of ultimate bearing capacity for expanded-base pile considering cavity contraction agree well with the measured values; however, the computations ignoring cavity contraction are 2.5-3.0 times the measured values. 展开更多
关键词 expanded-base PILE setup CAVITY CONTRACTION numeri
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