基于数字化脉冲处理器的α/β射线甄别方法研究

表面污染检测设备多采用ZnS(Ag)和塑料闪烁体组成的复合探测器对α/β射线进行同时测量,其中α/β射线的甄别方法至关重要。传统的甄别方法主要有脉冲幅度甄别法和脉冲宽度甄别法,其受模拟元件参数的影响而甄别稳定性降低。本文基于数字化脉冲处理器对α/β射线进行甄别,在FPGA内部构建电流恢复器、两路方形滤波器、比值计算器计算两路方形滤波器的输出峰值的比值。α/β射线在比值统计图中的不同区间呈高斯分布,由此实现对α/β射线的甄别。结果表明：该甄别方法能实时甄别出α/β射线,甄别品质因子为352,串道比均小于05%。对α、β探测效率分别不小于577%、37%。     

A new region-primitive method for classification of colour meat image texture based on size, orientation, and contrast

A new structural method was developed to characterise texture of colour meat images. Structural primitives or region-primitives were constructed using a region-growing method with a global and automatically calculated threshold. A total of eight textural features under the consideration of size, orientation, and contrast, which are the primary factors of human perception of texture pattern, were obtained from the region-primitives. An experiment was set up to classify the texture pattern of a set of 60 cooked meat colour images consisting of 20 beef images, 20 lamb images, and 20 pork images using texture features obtained from the proposed region-primitive method and run-length matrix method, respectively. The proposed region-primitive method (error rate: 18.3%) was found to perform better than the run-length matrix method (error rate: 35.0%). Results also indicated that the texture features obtained by the proposed method carried adequate texture information for classification and that the proposed region-primitive method could be potentially used for the characterisation of irregular textural pattern in cooked meat images, which was inapproachable by conventional structural texture analysis techniques.     

3种植物油傅里叶变换红外光谱信息的判别分析研究

针对花生油、大豆油和棕榈油样品,采用傅里叶变换红外光谱仪,采集红外吸收光谱,对光谱预处理后,提取红外特征信息,以1 746 cm-1和2 855 cm-1波数处吸收峰特征参数比值为X轴, 1 099 cm-1与1 119 cm-1波数处吸收峰特征参数的比值为Y轴,及3种油O-C-C对称伸缩振动各自所产生的吸收带所在波数(cm-1)值作为Z轴,绘制三维分布图,对这3种油样进行判别分析.结果显示这3种油样之间有明显区分.     

考虑价格歧视的端对端正负瓦特耦合市场:基于纳什谈判的合作模型EI北大核心CSCD

在碳达峰、碳中和的能源转型背景下,正负瓦特能量共享市场将是电力市场转型的重要方向之一。针对正负瓦特市场中能源共享的定价机制与多方合作模型展开研究。基于能源共享的定义,建立了去中心化的共享交易机制,并通过与中心化模型进行比较,证明了去中心化交易市场的效率。在传统去中心化的市场中考虑正负瓦特的交易与价格歧视的机制,通过引入价格歧视增强了能源产消者参与市场的积极性。基于纳什谈判模型建立能源产消者与系统运营商的合作关系,并将其等效为联盟效益最大化和交易支付谈判2个子问题,应用增广Benders分解算法在求解过程中保护各方主体的隐私。最后,通过仿真算例验证了价格歧视机制对能源产消者和系统运营商效益的积极影响。此外,基于纳什谈判的合作博弈可以产生额外的联盟合作效益,实现能源共享市场各主体效用的Pareto改进;去中心化的结构可以保证信息对称,促进市场公平。     

电子分析天平称量数据预处理方法研究

如何提高稳定度和灵敏度一直是电子分析天平的研究重点。本文介绍了电子分析天平的称重原理,构建了一种称量数据自适应滤波方法,以提高天平称量的稳定性和准确度;依据电磁力平衡传感器的动态响应特性,利用设定的多个阈值对连续称量数据单元进行多级判别,建立了一种称量数据多阈值判别方法,提高了天平的响应速度。计量测试结果表明,基于上述称量数据预处理方法研制的量程210g、分辨率0.1 mg的电子分析天平响应时间0.3s,稳定时间≤4s,称量的最大允许误差MPE≤±0.3mg,优于国家标准《JJG1036-2008电子天平检定规程》规定的一级天平示值误差指标。     

玄武岩类形成的大地构造环境Ta、Hf、Th、La、Zr、Nb比值对比判别

玄武质岩浆见于板块构造演化的全过程和各个重要阶段,是所有火成岩中最主要的构造地球化学指示剂,因此,玄武岩类相关元素图解和比值成为研究火成岩成岩作用和形成构造环境判别的首选对象。Ta、Hf、Th、La、Zr、Nb都是高场强元素和较强不相容元素,由于地球化学性质的相似性和在玄武岩类成岩过程中的规律性变化,所以它们是玄武岩类成因研究和构造环境判别图解中使用频率最高的元素,而且两两元素含量之间的比值能较好地区分其形成时的构造环境。在前人发明的玄武岩类Th/Hf-Ta/Hf、Th/Zr-Nb/Zr及La/Zr-Nb/Zr双对数判别图解基础上,运用这6个元素两两组对的Ta/Hf、Th/Ta、Th/Hf、Nb/Zr、Th/Nb、La/Nb值,建立比值判别表,极好地区分了几乎最常见的各种构造环境中有关的玄武岩类。该比值判别表是对双对数判别图解的极好补充。     

Modified variable return to scale back-propagation neural network robust parameter optimization procedure for multi-quality processes

Selecting the optimum process parameter level setting for multi-quality processes is cumbersome. Previous methods were plagued by complex computational search, unrealistic assumptions, ignoring the interrelationship between responses and failure to select optimum process parameter level settings. The methods of variable return to scale (VRS) back-propagation neural network (BPNN) previously adopted were limited by the use of weak models, poor discriminatory tendency and an inability to select the optimum parameter level setting. This study applied a modified VRS–adequate BPNN topology model in the robust parameter procedure to solve this problem. Here, standard VRS models are allowed to self-assess, leading to partitioning. The upper bound of the free variable of the VRS model is restricted and the VRS penalization coefficient is adopted to determine the optimum process parameter level setting. The effectiveness of the proposed model measured by the total anticipated improvement yielded the highest total improvement over the existing methods.     

Unambiguous discrimination among three linearly independent symmetric states

We investigate the unambiguous discrimination of three linearly independent symmetric states. We derive the minimum inconclusive probability by using an ancillary system and introducing a unitary transformation which acts on the input states and produces the output measured on the ancilla. We generalize to the case of discriminating the symmetric states with multiple copies. Our results show that the minimum inconclusive probabilities can be expressed as a form, not only dependent on the modular and the phase factors but also dependent on the number of the copies.