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一种基于变参考电平的零点凹口双重可控方向图综合改进方法

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北京理工大学学报 2024年第4期44卷 421-427页

作者：刘海波韩宇新武兴恺陈广茂北京理工大学信息与电子学院北京100081 北京理工大学信息与电子学院国家重点实验室电磁感知研究中心北京100081

为了解决基于变参考电平的自适应波束形成方法无法同时控制方向图零点和凹口的问题,研究了基于最大信噪比准则的任意阵列方向图综合方法,重点对主瓣宽度固定条件下能够实现最低等副瓣电平的方向图综合方法进行了理论分析,并对前人提出... 详细信息

为了解决基于变参考电平的自适应波束形成方法无法同时控制方向图零点和凹口的问题,研究了基于最大信噪比准则的任意阵列方向图综合方法,重点对主瓣宽度固定条件下能够实现最低等副瓣电平的方向图综合方法进行了理论分析,并对前人提出的可变参考电平参量进行了重新定义,新定义的变参考电平能够在波束主瓣宽度固定的前提下,同时产生等副瓣电平、可控凹口宽度和深度和可控零点深度的抗干扰波束,并通过计算机仿真验证了算法的有效性.该方法对于提升相控阵雷达对抗杂波和干扰性能具有较高的应用价值.

关键词：波束形成共形阵抗干扰

黄体酮软胶囊不同给药方式治疗围绝经期功能性子宫出血的效果比较

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中国药物滥用防治杂志 2024年第7期30卷 1272-1275页

作者：陈静韩玉新李小娟解放军联勤保障部队第九八八医院焦作院区妇产科河南焦作454000

目的:分析黄体酮软胶囊不同给药方式治疗围绝经期功能性子宫出血的效果。方法:于2019年12月—2020年12月本院治疗的90例围绝经期功能性子宫出血患者作为研究对象,应用随机数字表法分为实验组、参照组,每组45例。所有患者均采取黄体酮软... 详细信息

目的:分析黄体酮软胶囊不同给药方式治疗围绝经期功能性子宫出血的效果。方法:于2019年12月—2020年12月本院治疗的90例围绝经期功能性子宫出血患者作为研究对象,应用随机数字表法分为实验组、参照组,每组45例。所有患者均采取黄体酮软胶囊治疗,其中参照组接受口服给药,实验组接受阴道给药,比较两组治疗效果、性激素水平、月经情况、血液指标、复发情况。结果:实验组治疗总有效率为97.78%,高于参照组的86.67%(P<0.05);实验组治疗后月经时间短于参照组、月经量少于参照组(P<0.05);实验组治疗后bFGF、VEGF、血红蛋白水平高于参照组,PBC计分低于参照组(P<0.05);实验组治疗后FSH、LH、E2、P水平低于参照组(P<0.05);实验组复发率为2.22%,低于参照组的13.33%(P<0.05)。结论:予以围绝经期功能性子宫出血患者黄体酮软胶囊具有显著效果,且经阴道给药的疗效优于口服给药,能够明显改善性激素水平及月经情况,还可调节bFGF、VEGF水平,降低疾病复发率,用药价值理想。

关键词：黄体酮软胶囊给药方式围绝经期功能性子宫出血复发

基于FPGA彩色图像自适应巴特沃斯滤波器及其应用

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微电子学与计算机 2024年第1期41卷 83-92页

作者：韩玉鑫王晓凯山西大学物理电子工程学院山西太原030006

传统巴特沃斯滤波器无法对不同图像自适应调整截止频率。针对此问题,提出频率自适应二维巴特沃斯滤波器,通过高频能量在图像总能量中所占比值,自适应地调整截止频率。所采用色彩空间为色相饱和度(Hue Saturation Intensity,HSI),数据格... 详细信息

传统巴特沃斯滤波器无法对不同图像自适应调整截止频率。针对此问题,提出频率自适应二维巴特沃斯滤波器,通过高频能量在图像总能量中所占比值,自适应地调整截止频率。所采用色彩空间为色相饱和度(Hue Saturation Intensity,HSI),数据格式由浮点数取代定点数,实现高速、高精度的2D-快速傅里叶变换(Fast Fourier Transform,FFT)和2D-快速傅里叶逆变换(Inverse Fast Fourier Transform,IFFT)。深度考虑Xilinx 7系列现场可编辑门阵列(Field Programmable Gate Array,FPGA)硬件底层结构,在xc7a100tfgg484-3芯片上实现该滤波器,并在此基础上实现图像细节增强,增强后图像色彩无明显失真,图像细节更为丰富。经硬件仿真测试,分辨率为512×512的图像完成一次2D-FFT所需时间为6548.892μs,与软件计算频谱结构相似度高达99.9998%。整个设计在资源、功耗和性能之间进行了权衡。

关键词：自适应巴特沃斯滤波器 2D-FFT FPGA 图像增强

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重金属-PAHs污染土壤植物微生物修复效果及机理

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洁净煤技术 2024年第1期30卷 205-216页

作者：贾建丽高小龙张犇赵燊炜韩宇欣原浩坤王业荃中国矿业大学(北京)化学与环境工程学院北京100083

针对焦化厂等土壤中铬(Cr)、砷(As)重(类)金属和菲(Phe)、苯并[a]芘(BaP)等多环芳烃(PAHs)风险高、绿色低碳修复技术缺乏等突出问题,以黑麦草-玉米-食醚红球菌(Rhodococcus aetherivorans,BW2)开展植物微生物联合。结果表明,63 d后植物... 详细信息

针对焦化厂等土壤中铬(Cr)、砷(As)重(类)金属和菲(Phe)、苯并[a]芘(BaP)等多环芳烃(PAHs)风险高、绿色低碳修复技术缺乏等突出问题,以黑麦草-玉米-食醚红球菌(Rhodococcus aetherivorans,BW2)开展植物微生物联合。结果表明,63 d后植物微生物联合修复组土壤中Cr、As、Phe和BaP浓度分别下降9.63%、5.28%、45.14%和26.87%,其中重金属的去除主要依赖于植物作用,而PAHs去除则在很大程度上取决于微生物与植物的共同作用;植物主要吸收可提取态重金属,63 d后不同修复组土壤中可交换态Cr平均下降2.19%,而As则由于降解作用使修复过程中可交换态增加;可交换态Cr和碳酸盐结合态Cr与土壤中放线菌门呈强正相关,2种形态As则与拟杆菌门、装甲菌门、FBP菌门和浮霉菌门呈正相关。污染物去除效率间存在明显的相互作用,同时受酶活性和不同功能微生物丰度的动态影响,反之土壤微生物群落结构和功能也在土壤污染物种类、浓度及理化性质等综合作用下发生改变。

关键词：重金属-多环芳烃复合污染土壤食醚红球菌黑麦草-玉米联合修复

肥胖和骨质疏松之间的关联:一项两样本双向孟德尔随机化分析

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中国组织工程研究 2024年第27期28卷 4319-4324页

作者：詹群璋张钰玲韩雨欣吕嘉振郑晓霞曲崇正广州中医药大学广东省广州市510405 广州中医药大学第三附属医院针灸推拿科广东省广州市510378

背景:多项临床研究观察表明肥胖与骨质疏松症之间存在密切关系,但肥胖与骨质疏松症之间是否存在遗传因果效应尚不清楚。目的:利用大规模全基因组关联研究的汇总数据,通过孟德尔随机化分析探究肥胖和骨质疏松之间的关联。方法:肥胖数据... 详细信息

背景:多项临床研究观察表明肥胖与骨质疏松症之间存在密切关系,但肥胖与骨质疏松症之间是否存在遗传因果效应尚不清楚。目的:利用大规模全基因组关联研究的汇总数据,通过孟德尔随机化分析探究肥胖和骨质疏松之间的关联。方法:肥胖数据来自人体特征遗传调查(GIANT)和英国生物样本库(UKBB)的汇总统计数据。骨质疏松症的数据来自从骨质疏松症遗传因素联盟(GeFOS)获得的2种骨密度表型:全身骨密度和跟骨骨密度。逆方差加权法为主要分析方法,基于Egger回归的孟德尔随机化法(Mendelian randomization method based on Egger regression,MR-Egger)和加权中位数法作为补充方法来计算肥胖遗传变异与骨质疏松症之间的因果关联。采用敏感性分析来验证结果的可靠性,利用Cochran’s Q检验分析结果的异质性,利用MR-Egger截距检验分析结果的水平多效性,留一法评估合并的逆方差加权法估计值是否具有潜在影响的单核苷酸多态性。结果与结论:①肥胖对骨质疏松症的影响:除身体质量指数与前臂骨密度外,身体质量指数、腰臀比、经身体质量指数调整的腰臀比与全身骨密度、跟骨骨密度、前臂骨密度、腰椎骨密度及股骨颈骨密度两两之间呈正向因果关系;进一步Meta分析显示,肥胖会增加骨密度的风险(OR=1.08,95%CI:1.05-1.11,P<0.01);②骨质疏松症对肥胖的影响:除了前臂骨密度、腰椎骨密度作为暴露因素对肥胖有因果关系外,其他数据集均显示全身骨密度、跟骨骨密度、股骨颈骨密度与肥胖之间不呈现因果效应;进一步Meta分析显示,骨密度并不会增加肥胖的风险(OR=0.99,95%CI:0.98-1.01,P<0.01)。③结果证实:肥胖与骨质疏松之间存在因果关系,即肥胖可能是骨质疏松症的危险性因素,但未发现骨质疏松症对于肥胖的因果关联。

关键词：肥胖骨质疏松症孟德尔随机化因果关系骨密度 Meta分析身体质量指数

Numerical simulation of the dynamic effects of grounding icebergs on summer circulation in Prydz Bay,Antarctica

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Advances in Polar Science 2022年第2期33卷 135-144页

作者： han yuxin SHI Jiuxin HOU Saisai XIAO Changhao Physical Oceanography Laboratory Ocean University of ChinaQingdao 266100China Qingdao National Laboratory for Marine Science and Technology Qingdao 266237China

The Regional Ocean Modeling System(ROMS)is employed to create a three-dimensional numerical model of the summer circulation in the Prydz Bay region,*** with the currents measured using an underway acoustic Doppler current profiler during a Chinese cruise,the simulated current field illustrates the major features of the Prydz Bay circulation,including the Antarctic Slope Current(ASC)along the continental shelf break,the cyclonic Prydz Bay Gyre,and the Prydz Bay Eastern Coastal Current(PBECC).The effects of grounding icebergs D15 and B15 on the circulation in Prydz Bay are investigated via numerical *** results indicate that these giant grounding icebergs substantially affect the flows into and within the bay,which may differ with the different grounding *** grounding iceberg D15 is located close to the southwestern part of the West Ice Shelf(WIS),it cuts off the coastal current along the outer edge of the WIS,and the ASC can only enter Prydz Bay from the west side of iceberg D15,whereupon it becomes a main source of the *** D15 also weakens the circulation in the bay in *** relatively small iceberg B15 entered Prydz Bay from 2007 to 2009 and grounded on the southwestern section of the Four Ladies *** numerical experiments indicate that iceberg B15 guides the ASC flowing into the bay around its west side and reduces the width of the inflow on the eastern side of the Prydz Bay *** grounding of iceberg B15 has also led to adjustments of the circulation within the bay,among which the most significant is that the outflow along the western flank of Fram Bank has shifted to the west and become more intensive.

关键词： circulation grounding iceberg numerical simulation Prydz Bay Antarctica

Plasma-exfoliated g-C_(3)N_(4) with oxygen doping: tailoring photocatalytic properties

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Frontiers of Chemical Science and Engineering 2024年第2期18卷 27-39页

作者： yuxin Li Junxin Guo Rui han Zhao Wang National Engineering Research Centre of Industry Crystallization Technology School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

Heteroatom doping and defect engineering have been proposed as effective ways to modulate the energy band structure and improve the photocatalytic activity of g-C_(3)N_(4). In this work, ultrathin defective g-C_(3)N_(4) was successfully prepared using cold plasma. Plasma exfoliation reduces the thickness of g-C_(3)N_(4) from 10 nm to 3 nm, while simultaneously introducing a large number of nitrogen defects and oxygen atoms into g-C_(3)N_(4). The amount of doped O was regulated by varying the time and power of the plasma treatment. Due to N vacancies, O atoms formed strong bonds with C atoms, resulting in O doping in g-C_(3)N_(4). The mechanism of plasma treatment involves oxygen etching and gas expansion. Photocatalytic experiments demonstrated that appropriate amount of O doping improved the photocatalytic degradation of rhodamine B compared with pure g-C_(3)N_(4). The introduction of O optimized the energy band structure and photoelectric properties of g-C_(3)N_(4). Active species trapping experiments revealed ·O_(2)^(–) as the main active species during the degradation.

关键词： graphitic carbon nitride cold plasma oxygen doping nitrogen defect visible-light photocatalysis

Monocular Distance Estimated Based on PTZ Camera

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Computers, Materials & Continua 2024年第5期79卷 3417-3433页

作者： Qirui Zhong Xiaogang Cheng yuxin Song han Wang Bell Honors School Nanjing University of Posts and Telecommunications Nanjing210003China College of Telecommunications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing210003China College of Automation and College of Artificial Intelligence Nanjing University of Posts and TelecommunicationsNanjing210003China

This paper introduces an intelligent computational approach for extracting salient objects fromimages and estimatingtheir distance information with PTZ (Pan-Tilt-Zoom) cameras. PTZ cameras have found wide applications innumerous public places, serving various purposes such as public securitymanagement, natural disastermonitoring,and crisis alarms, particularly with the rapid development of Artificial Intelligence and global infrastructuralprojects. In this paper, we combine Gauss optical principles with the PTZ camera’s capabilities of horizontal andpitch rotation, as well as optical zoom, to estimate the distance of the *** present a novel monocular objectdistance estimation model based on the Focal Length-Target Pixel Size (FLTPS) relationship, achieving an accuracyrate of over 95% for objects within a 5 km range. The salient object extraction is achieved through a simplifiedconvolution kernel and the utilization of the object’s RGB features, which offer significantly faster computingspeeds compared to Convolutional Neural Networks (CNNs). Additionally, we introduce the dark channel beforethe fog removal algorithm, resulting in a 20 dB increase in image definition, which significantly benefits distanceestimation. Our system offers the advantages of stability and low device load, making it an asset for public securityaffairs and providing a reference point for future developments in surveillance hardware.

关键词： Public security location information PTZ camera image processing

On the electric behaviour of conductive grease inside the contact zone

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Friction 2024年第4期12卷 683-697页

作者： yuxin ZHOU Jinjie LIU Xinming LI He CHONG Bo han Qinghua BAI SKF(Shanghai)Automotive Technologies Co. Ltd.Shanghai 201814China School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao 266250China

Conductive grease has been considered as a potential solution in addressing electric erosion issue inside motor *** the conductive grease performance,especially the electric and tribological behaviour is crucial for its *** paper combines bulk grease characterization and contact film study considering both electrical and tribological loading *** results show that the electric performance for the selected conductive grease sample is electric field dependent,including both frequency and voltage *** film impedance inside the contact area is closely related to the external electric field,running condition,and lubrication *** following film impedance calculation tells that not only bulk grease electric parameters,but the contact parameter,lubricant film contour and lubrication condition should be considered when performing the overall bearing electrical modelling.

关键词： Electric erosion lubricant conductivity grease film impedance