This paper presents a technique to reproduce compatible seismogran3s involving permanent displacen3ent effects at sites close to the fault source. A multi-objective evolutionary algorithm is used to minimize the diffe...This paper presents a technique to reproduce compatible seismogran3s involving permanent displacen3ent effects at sites close to the fault source. A multi-objective evolutionary algorithm is used to minimize the differences between the response spectra and multi-tapered power spectral delsilies corresponding to the recorded and simulated wavelbrms. The multi-taper method is used to reduce the spectral leakage that is inherent in the Fourier rams formed form ofwavelbrms, ieading to a reduction of variance in power spectral amplitudes, thus permitting the calibration of the two sets of data. The technique is implemented using the 1998-Fandoqa （lran） earthquake data and the results are compared with the actual observed data. Additionally, a comparison is made with a SAR interfcrometry study leading to fair agreement with the reported dislocation along the main fault. The simulation procedure and results are discussed and assessed concluding that, although the technique may be associated with uncertainties, it can still be used to reproduce wavelbnns at near source sites that include permanent dislocation, and can be used for seismic pertbrmance evaluation of structures in the region under study.展开更多
In this paper, a distributed algorithm is proposed to solve a kind of multi-objective optimization problem based on the alternating direction method of multipliers. Compared with the centralized algorithms, this algor...In this paper, a distributed algorithm is proposed to solve a kind of multi-objective optimization problem based on the alternating direction method of multipliers. Compared with the centralized algorithms, this algorithm does not need a central node. Therefore, it has the characteristics of low communication burden and high privacy. In addition, numerical experiments are provided to validate the effectiveness of the proposed algorithm.展开更多
Spatial data, including geometrical data, attribute data, image data and DEM data, are huge in volume and relations among them are complex. How to effectively organize and manage those data is an important problem in ...Spatial data, including geometrical data, attribute data, image data and DEM data, are huge in volume and relations among them are complex. How to effectively organize and manage those data is an important problem in GIS. Several problems about space data organization and management in GeoStar which is a basic GIS software made in China are discussed in this paper. The paper emphasizes on object model of spatial vector, data organization, data management and how to realize the goal, and the like.展开更多
In the constrained reentry trajectory design of hypersonic vehicles, multiple objectives with priorities bring about more difficulties to find the optimal solution. Therefore, a multi-objective reentry trajectory opti...In the constrained reentry trajectory design of hypersonic vehicles, multiple objectives with priorities bring about more difficulties to find the optimal solution. Therefore, a multi-objective reentry trajectory optimization (MORTO) approach via generalized varying domain (GVD) is proposed. Using the direct collocation approach, the trajectory optimization problem involving multiple objectives is discretized into a nonlinear multi-objective programming with priorities. In terms of fuzzy sets, the objectives are fuzzified into three types of fuzzy goals, and their constant tolerances are substituted by the varying domains. According to the principle that the objective with higher priority has higher satisfactory degree, the priority requirement is modeled as the order constraints of the varying domains. The corresponding two-side, single-side, and hybrid-side varying domain models are formulated for three fuzzy relations respectively. By regulating the parameter, the optimal reentry trajectory satisfying priorities can be achieved. Moreover, the performance about the parameter is analyzed, and the algorithm to find its specific value for maximum priority difference is proposed. The simulations demonstrate the effectiveness of the proposed method for hypersonic vehicles, and the comparisons with the traditional methods and sensitivity analysis are presented.展开更多
目的观察临床操作技能评估(Direct observation of procedural skills,DOPS)为工具的形成性评价在临床医学学士(Bachelor of Medicine,MBBS)心肺复苏教学中的应用效果。方法选择北华大学附属医院、临床医学院2020届MBBS毕业实习生为对照...目的观察临床操作技能评估(Direct observation of procedural skills,DOPS)为工具的形成性评价在临床医学学士(Bachelor of Medicine,MBBS)心肺复苏教学中的应用效果。方法选择北华大学附属医院、临床医学院2020届MBBS毕业实习生为对照组,2021届MBBS毕业实习生为试验组。对照组心肺复苏教学采用客观结构化临床考试(objective structured clini‐cal examination,OSCE)模式,试验组采用OSCE+DOPS模式。观察两组理论知识与技能考核成绩。问卷调查试验组对DOPS为工具的形成性评价体系应用满意度。结果对照组技能考核成绩(88.6±5.6)分,明显低于试验组的(98.0±3.2)分(P<0.05)。试验组学生认为DOPS形成性评价的运用可提高临床急救能力和临床思维能力、激发学习兴趣、巩固理论知识的学习,提高学生开展急救的信心,提高临床分析、解决问题的能力。结论应用DOPS为工具的形成性评价可以提高在MBBS心肺复苏教学效果。展开更多
近年来,无人机因体积小、灵活性好等优势被广泛应用在车辆跟踪领域。当无人机在高空飞行时,其捕捉的图像中车辆目标存在像素点少、拥挤以及被遮挡的情况。现有的多目标跟踪研究方法在车辆被遮挡过程中发生非线性运动时,使用卡尔曼滤波预...近年来,无人机因体积小、灵活性好等优势被广泛应用在车辆跟踪领域。当无人机在高空飞行时,其捕捉的图像中车辆目标存在像素点少、拥挤以及被遮挡的情况。现有的多目标跟踪研究方法在车辆被遮挡过程中发生非线性运动时,使用卡尔曼滤波预测,会出现车辆位置预测不准确的问题。为了解决这些问题,采用先检测后跟踪(tracking by detection,TBD)范式,对YOLOv8检测算法进行改进,在网络结构中引入了BiFormer稀疏动态注意力模块,用于提取小目标特征信息。同时使用轻量级上采样算子CARAFE替换原最近邻插值上采样,减少上采样过程中小目标特征丢失的问题。提出一种轻量化跟踪模型FA-SORT,针对SORT算法提出三点改进:改进KF、添加速度方向一致性匹配和检测值匹配。在自制地组合了多个车辆数据集上验证改进的YOLOv8算法。实验结果表明,与YOLOv8相比,精确率(precision)提高了0.97%,召回率(recall)提高了0.898%。对所提出的FA-SORT算法使用UAVDT数据集进行验证,结果表明,与现有的多目标跟踪算法相比,HOTA指标首个达到70.05%,IDF1达到87.45%,跟踪速度达到29.93 FPS。验证了FA-SORT跟踪算法在多车辆跟踪任务中的优越性。展开更多
文摘This paper presents a technique to reproduce compatible seismogran3s involving permanent displacen3ent effects at sites close to the fault source. A multi-objective evolutionary algorithm is used to minimize the differences between the response spectra and multi-tapered power spectral delsilies corresponding to the recorded and simulated wavelbrms. The multi-taper method is used to reduce the spectral leakage that is inherent in the Fourier rams formed form ofwavelbrms, ieading to a reduction of variance in power spectral amplitudes, thus permitting the calibration of the two sets of data. The technique is implemented using the 1998-Fandoqa （lran） earthquake data and the results are compared with the actual observed data. Additionally, a comparison is made with a SAR interfcrometry study leading to fair agreement with the reported dislocation along the main fault. The simulation procedure and results are discussed and assessed concluding that, although the technique may be associated with uncertainties, it can still be used to reproduce wavelbnns at near source sites that include permanent dislocation, and can be used for seismic pertbrmance evaluation of structures in the region under study.
文摘In this paper, a distributed algorithm is proposed to solve a kind of multi-objective optimization problem based on the alternating direction method of multipliers. Compared with the centralized algorithms, this algorithm does not need a central node. Therefore, it has the characteristics of low communication burden and high privacy. In addition, numerical experiments are provided to validate the effectiveness of the proposed algorithm.
文摘Spatial data, including geometrical data, attribute data, image data and DEM data, are huge in volume and relations among them are complex. How to effectively organize and manage those data is an important problem in GIS. Several problems about space data organization and management in GeoStar which is a basic GIS software made in China are discussed in this paper. The paper emphasizes on object model of spatial vector, data organization, data management and how to realize the goal, and the like.
基金supported by the Natural Science Foundation of Tianjin(12JCZDJC30300)the Research Foundation of Tianjin Key Laboratory of Process Measurement and Control(TKLPMC-201613)the State Scholarship Fund of China
文摘In the constrained reentry trajectory design of hypersonic vehicles, multiple objectives with priorities bring about more difficulties to find the optimal solution. Therefore, a multi-objective reentry trajectory optimization (MORTO) approach via generalized varying domain (GVD) is proposed. Using the direct collocation approach, the trajectory optimization problem involving multiple objectives is discretized into a nonlinear multi-objective programming with priorities. In terms of fuzzy sets, the objectives are fuzzified into three types of fuzzy goals, and their constant tolerances are substituted by the varying domains. According to the principle that the objective with higher priority has higher satisfactory degree, the priority requirement is modeled as the order constraints of the varying domains. The corresponding two-side, single-side, and hybrid-side varying domain models are formulated for three fuzzy relations respectively. By regulating the parameter, the optimal reentry trajectory satisfying priorities can be achieved. Moreover, the performance about the parameter is analyzed, and the algorithm to find its specific value for maximum priority difference is proposed. The simulations demonstrate the effectiveness of the proposed method for hypersonic vehicles, and the comparisons with the traditional methods and sensitivity analysis are presented.
文摘目的观察临床操作技能评估(Direct observation of procedural skills,DOPS)为工具的形成性评价在临床医学学士(Bachelor of Medicine,MBBS)心肺复苏教学中的应用效果。方法选择北华大学附属医院、临床医学院2020届MBBS毕业实习生为对照组,2021届MBBS毕业实习生为试验组。对照组心肺复苏教学采用客观结构化临床考试(objective structured clini‐cal examination,OSCE)模式,试验组采用OSCE+DOPS模式。观察两组理论知识与技能考核成绩。问卷调查试验组对DOPS为工具的形成性评价体系应用满意度。结果对照组技能考核成绩(88.6±5.6)分,明显低于试验组的(98.0±3.2)分(P<0.05)。试验组学生认为DOPS形成性评价的运用可提高临床急救能力和临床思维能力、激发学习兴趣、巩固理论知识的学习,提高学生开展急救的信心,提高临床分析、解决问题的能力。结论应用DOPS为工具的形成性评价可以提高在MBBS心肺复苏教学效果。
文摘近年来,无人机因体积小、灵活性好等优势被广泛应用在车辆跟踪领域。当无人机在高空飞行时,其捕捉的图像中车辆目标存在像素点少、拥挤以及被遮挡的情况。现有的多目标跟踪研究方法在车辆被遮挡过程中发生非线性运动时,使用卡尔曼滤波预测,会出现车辆位置预测不准确的问题。为了解决这些问题,采用先检测后跟踪(tracking by detection,TBD)范式,对YOLOv8检测算法进行改进,在网络结构中引入了BiFormer稀疏动态注意力模块,用于提取小目标特征信息。同时使用轻量级上采样算子CARAFE替换原最近邻插值上采样,减少上采样过程中小目标特征丢失的问题。提出一种轻量化跟踪模型FA-SORT,针对SORT算法提出三点改进:改进KF、添加速度方向一致性匹配和检测值匹配。在自制地组合了多个车辆数据集上验证改进的YOLOv8算法。实验结果表明,与YOLOv8相比,精确率(precision)提高了0.97%,召回率(recall)提高了0.898%。对所提出的FA-SORT算法使用UAVDT数据集进行验证,结果表明,与现有的多目标跟踪算法相比,HOTA指标首个达到70.05%,IDF1达到87.45%,跟踪速度达到29.93 FPS。验证了FA-SORT跟踪算法在多车辆跟踪任务中的优越性。
