基于小波核双重加权SVM模型的蓝藻水华识别与变化检测

以淀山湖为研究区域,利用Landsat系列遥感影像,提出了归一化蓝藻指数的构建方法,结合波段组合和Gabor滤波器构建多特征空间,并基于变精度粗糙集和灰色关联决策相结合的方法进行特征空间的优化。在此基础上,采用小波核双重加权SVM分类模型,得到研究区蓝藻水华空间分布格局的识别与检测结果。以误差矩阵证明此分类模型能够较准确地识别出蓝藻水华覆盖区,满足环境调查的要求。研究成果为淀山湖蓝藻水华的防治和水生生态系统的保护提供了科学依据。

六胺银加马松三色双重染色在肾穿刺活检组织中的应用

肾小球病是发病率较高的疾病，肾穿刺检查是确诊肾脏疾病的重要手段，光镜观察肾组织病变在进行肾小疾球疾病诊断和分类工作中起重要作用。常规HE染色不能清晰地显示肾小球基膜，在实际工作中除免疫荧光抗体检测外，PAS、PASM、Masson特殊染色才能将基膜清晰地显示出来。尤其是六胺银加马松三色双重染色在光镜下观察基膜增厚和钉突、双轨，对诊断膜性。肾小球肾炎及其它各种肾小球疾病有重要价值，是观察肾小球基膜改变的重要方法之一。

输尿管扩张加双重双J管置入治疗输尿管中下段狭窄

目的探讨输尿管扩张加双重双J管置入治疗输尿管中下段狭窄的临床疗效。方法 65例输尿管中下段狭窄患者,依据随机数字法分为观察组(33例)和对照组(32例),观察组采取输尿管扩张加双重双J管置入治疗,对照组采取传统开放性手术治疗,对比两组患者手术治疗效果和并发症发生率。结果观察组并发症发生率为6.06%,治疗总有效率为96.97%;对照组并发症发生率为25.00%,治疗总有效率为81.25%;两组患者并发症发生率和治疗总有效率比较,差异均有统计学意义(P<0.05)。结论输尿管扩张加双重双J管置入治疗输尿管中下段狭窄的临床疗效显著,患者并发症发生率较低,值得推广应用。

B超、双重胆囊胆道造影与手术病理133例的对照研究

本文报道133例胆系手术,术前均经B超和口服加静脉双重胆囊胆道造影检查,依据手术病理结果,对两种诊断方法进行评价。B超与口服加静脉双重胆囊胆道造影相比较,诊断胆囊结石敏感度分别为98.23％,74.76％;特异度8O％,88.89％;准确度95.49％,77.69％。结果显示,对于胆囊疾病的诊断,B超优于口服加静脉双重胆囊胆道造影。当B超检查未显示胆囊或不能作出结论,或临床高度疑有胆囊疾病而未证实时,酌情作口服胆囊造影。静脉胆道造影对诊断胆管病变价值不高。

复合材料层合板的高阶理论

应用双重迭加方法 ,对复合材料层合板建立和导出了未知量不随层数而变化 ,且满足层间横向剪应力和位移连续性条件的位移场模型以及相应的位移形式的平衡方程和边界条件 .

基于双有源桥的三端口变换器回流功率优化控制

为了实现对负载连续稳定的供电,采用新能源发电与储能相结合的能源结构业已成为电力系统的主流热点技术.本文针对该储能中交错并联双向Buck-Boost与双有源桥构成的集成三端口变换器运行控制中所存在的功率回流问题,详细分析回流功率的产生机理,建立了该集成三端口变换器的传输功率与回流功率数学模型.研究了回流功率与传输功率的耦合关系,提出基于单闭环的集成三端口变换器最小回流功率控制的优化控制策略.采用PSIM进行仿真,对比分析了集成三端口变换器的回流功率的变化,验证了通过简单的调制策略即可实现稳定的输出.

未来大湾区文旅产业需要全力成就的5件大事

文旅业态创新的主要方式有三个,一是文化重塑,就是深度向旅游业态注入文化理念、文化资源、文化遗产、文化产业,实现文旅的高度创新融合发展;二是科技异变,通过AR、VR、人工智能、全息技术等先进科技成果的导入,推升和创新文旅业态;三是场景要素整合,利用文旅空间特点,注入可改变空间和场景的创新价值和设计,例如当下流行的沉浸式体验文旅新业态和产品。

基于SAPSO算法的集成型三端口变换器回流功率优化

占空比加双重移相控制下的交错并联Buck-Boost和双有源全桥集成的三端口变换器功率密度高、工作方式灵活、应用广泛,但是由于控制方式较为复杂,回流功率高也成为其发展的瓶颈。针对该集成型三端口变换器工作过程中存在的功率回流问题,分析了回流功率产生原理,建立了此变换器传输功率与回流功率数学模型,得到了回流功率与占空比和移相占空比的关系方程;基于此方程,采用模拟退火粒子群算法对占空比与移相角进行优化。通过运行工况为输入电压100 V、输出电压48 V、开关频率20 kHz的仿真与实验结果表明:所提方法可以实现减小回流功率的目标回流功率减少近13%,与模拟退火算法相比,该方法使集成型三端口变换器的回流功率明显降低。

A group decision making method based on double hesitant linguistic preference relations

A simple decision method is proposed to solve the group decision making problems in which the weights of decision organizations are unknown and the preferences for alternatives are provided by double hesitant linguistic preference relations. First, double hesitant linguistic elements are defined as representing the uncertain assessment information in the process of group decision making accurately and comprehensively, and the double hesitant linguistic weighted averaging operator is developed based on the defined operational laws for double hesitant linguistic elements. Then, double hesitant linguistic preference relations are defined and a means to objectively determine the weights of decision organizations is put forward using the standard deviation of scores of preferences provided by the individual decision organization for altematives. Finally the correlation coefficient between the scores of preferences and the scores of preferences are provided by the other decision organizations. Accordingly, a group decision method based on double hesitant linguistic preference relations is proposed, and a practical example of the Jiudianxia reservoir operation alternative selection is used to illustrate the practicability and validity of the method. Finally, the proposed method is compared with the existing methods. Comparative results show that the proposed method can deal with the double hesitant linguistic preference information directly, does not need any information transformation, and can thus reduce the loss of original decision information.

Analysis of the Pragmatic Functions of Double Negative

Double negative in English has three functions： to strengthen the affirmatives, and to affirm euphemism and to strengthen the negative meaning, which are analyzed in the present paper.

FEM analyses for influences of stress corrosion and pressure solution on THM coupling in dual-porosity rock mass

With the models of stress corrosion and pressure solution, by Yasuhara et al., two computation conditions were designed for a hypothetical nuclear waste repository in an unsaturated dual-porosity rock mass: (i) the fracture apertures are changed with the stress corrosion and pressure solution (the porosity of rock matrix is also a function of stress); (ii) the fracture apertures and the porosity of rock matrix are constants. Then the corresponding two-dimensional FEM analyses for the coupled thermohydro-mechanical processes were carried out, and the states of temperatures, rates and magnitudes of aperture closure, pore pressures, flow velocities and stresses in the rock mass were investigated. The results show the followings: The aperture closure rates caused by stress corrosion are almost six orders higher than those caused by pressure solution, and the two kinds of closure rates climb up, then decline, furthermore tend towards stability; the fracture apertures decrease from the original value and tend towards the residual value, and the contact-area ratios of asperities increase also from the original value and tend towards the nominal value; when the effects of stress corrosion and pressure solution are considered, the negative fracture pressures in near field rise very highly; the differences between the magnitudes and distributions of stresses within the rock mass in two calculation cases are very small.