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低本高效人脸识别系统设计的汽车记忆座椅模块开发

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科学技术与工程 2024年第13期24卷 5443-5449页

作者：肖森安嘉骏高雨李伟亮刘晓昂河北工业大学亚利桑那工业学院天津300401 河北工业大学机械工程学院天津300401

近年来,记忆座椅作为一种新型的座椅形式,因其简便的操作过程受到广大消费者的青睐。但是目前国内外绝大多数的记忆座椅仍然面临着成本高、调节准确度低的问题。为改善车主的使用体验,提出一种座椅自适应调节电控模块,基于人脸识别技术... 详细信息

近年来,记忆座椅作为一种新型的座椅形式,因其简便的操作过程受到广大消费者的青睐。但是目前国内外绝大多数的记忆座椅仍然面临着成本高、调节准确度低的问题。为改善车主的使用体验,提出一种座椅自适应调节电控模块,基于人脸识别技术,通过更加简洁高效的代码使得操作更加便捷、调节更加准确。首先,通过单片机使用OpenCV确定最佳人体识别方案;然后运用微型控制器(microcontroller unit,MCU)自动控制技术进行座椅控制系统的电路设计及电控程序的编写;最后使用STM32单片机运行电控模块并进行验证,识别成功率达92%。研究结果显示,该人脸识别系统在保证了识别准确率的同时控制了成本,结合汽车中的记忆座椅后对于简化座椅调整流程、改善用户实际体验效果具有实际意义。

关键词：记忆座椅电控模块人脸识别哈尔特征 OpenCV 树莓派

Dot-shaped beamforming analysis of subarray-based sin-FDA

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Frontiers of Information Technology & electronic engineering 2019年第10期20卷 1429-1444页

作者： Bo Wang Jun-wei XIe Jing ZHang Jia-ang Ge Air and Missile Defense College Air Force Engineering UniversityXi'an 710051China Shaanxi Vocational and Technical College of Transport Xi'an 710018China

Phased array (PA) radar is one of the most popular ty.es of radar. In contrast to PA, the frequency diverse array (FDA) is a potential solution to suppress range-related interference because of its time-range-angle-dependent beampattern. However, the range-angle coupling inherent in the FDA transmit beampattern may degrade the output signal-to-interference-plus-noise ratio (sinR). We propose a dot-shaped beamforming method based on the analy.ed four subarray-based FDAs and subarray-based planar FDAs using a sinusoidally increasing frequency offset with elements transmitting at multiple frequencies. The numerical results show that the proposed approach outperforms the existing log-FDA with logarithmical frequency offset in transmit energy focus, sidelobe suppression, and array resolution. Comparative simulation results validate the effectiveness of the proposed method.

关键词： Frequency diverse array Subarray-based frequency diverse array Decoupling Dot-shaped beamforming

2014—2021年北京市儿童过敏性疾病门诊就诊构成比及变化趋势分析

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中国全科医学 2024年第27期27卷 3395-3400页

作者：侯晓玲皇惠杰姜楠楠李昂孔勤魏勉向莉国家儿童医学中心、儿科重大疾病教育部重点试验室、国家呼吸系统疾病临床医学研究中心、首都医科大学附属北京儿童医院过敏反应科北京市100045 国家儿童医学中心、儿科重大疾病教育部重点试验室、国家呼吸系统疾病临床医学研究中心、首都医科大学附属北京儿童医院信息中心北京市100045

背景过敏性疾病的患病率在全球人群中急剧增长,已经影响着10%~40%的世界人口。该类疾病常在儿童期始发,但我国尚缺乏10年内儿童过敏性疾病发病率趋势分析数据,本研究拟通过对单中心电子病历数据进行挖掘,从而为国内过敏性疾病预防和管... 详细信息

背景过敏性疾病的患病率在全球人群中急剧增长,已经影响着10%~40%的世界人口。该类疾病常在儿童期始发,但我国尚缺乏10年内儿童过敏性疾病发病率趋势分析数据,本研究拟通过对单中心电子病历数据进行挖掘,从而为国内过敏性疾病预防和管理工作的开展提供流行病学支持。目的分析2014—2021年首都医科大学附属北京儿童医院0~18岁儿童过敏性疾病门诊就诊年度构成比及变化趋势。方法回顾性分析首都医科大学附属北京儿童医院2014—2021年医院信息系统门诊电子病历数据,对过敏性疾病就诊年度构成比及变化趋势进行分析。计算不同性别、年龄过敏性疾病包括湿疹、荨麻疹、过敏性鼻炎、支气管哮喘、过敏性咳嗽、过敏性结膜炎、食物过敏、药物过敏、花粉症、严重过敏反应等疾病的就诊年度构成比。进一步分析年度构成比排名稳定在前10位的过敏性疾病构成比变化趋势。结果2014—2021年门诊过敏性疾病就诊儿童累计1231890例次,去除缺失数据后共纳入1231863例次,其中男童727082例次(59.0%),女童504781例次(41.0%);过敏性疾病就诊患儿年龄以3岁以下为主(46.9%)。删除过敏性紫癜、支气管炎、呼吸道感染等非免疫球蛋白e介导的过敏性疾病,纳入疾病谱分析病例1208265例次。2016—2021年首都医科大学附属北京儿童医院儿童过敏性疾病门诊就诊例次在全院门诊就诊例次中的占比呈上升趋势。2014—2017年儿童过敏性疾病门诊就诊构成比前5位分别是湿疹、荨麻疹、过敏性鼻炎、支气管哮喘、过敏性咳嗽;2018—2021年儿童过敏性疾病门诊就诊构成比前5位分别是过敏性鼻炎、湿疹、荨麻疹、过敏性结膜炎、支气管哮喘。年度构成比变化趋势分析显示,2014—2021年,过敏性鼻炎、过敏性结膜炎及食物过敏占全部过敏性疾病的构成比呈逐年上升趋势,构成比峰值分别达45.4%、11.1%及2.8%;湿疹、荨麻疹及支气管哮喘构成比呈下降趋势,构成比峰值分别为46.5%、24.9%及11.3%。结论2016—2021年首都医科大学附属北京儿童医院儿童过敏性疾病门诊就诊例次在全院门诊就诊例次中的占比呈上升趋势;2014—2021年,过敏性鼻炎、过敏性结膜炎及食物过敏年度构成比呈上升趋势,湿疹、荨麻疹及支气管哮喘年度构成比呈下降趋势。

关键词：过敏反应过敏性疾病儿童门诊医疗构成比趋势分析北京

extensive spectral tuning of the proton transfer emission from green to red via a rational derivatization of salicylideneaniline

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Chinese Chemical Letters 2012年第11期23卷 1279-1282页

作者： Hsing yang Tsai sin Kai Fang Kew yu Chen Department of Chemical engineering Feng Chia University

A series of salicylideneaniline derivatives 1a-lf were synthesized under mild condition in high y.elds, and characterized by ^1H NMR, HRMS, UV-vis and emission spectra. In solid and aprotic solvents 1a-1f exist mainly as e conformers that possess a sixmembered-ring hydrogen bond and undergo excited-state intramolecular proton transfer （eSIPT） reactions, resulting in a protontransfer tautomer emission. Depending on the electronic donor or acceptor strength of the substituent in either the HOMO or LUMO site, a broad tuning range of the emission from green （1c） to red （1a） has been achieved.

关键词： eSIPT Schiff bases Salicylideneaniline derivatives Db'T calculations

effects of osmotic stress on the expression profiling of aquaporin genes in the roughskin sculpin(Trachidermus fasciatus)

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Acta Oceanologica sinica 2020年第6期39卷 19-25页

作者： Qian Ma Xinfu Liu ang Li Shufang Liu Zhimeng Zhuang College of Fisheries Guangdong Ocean UniversityZhanjiang 524088China yellow Sea Fisheries Research Institute Chinese Academy of Fishery SciencesQingdao 266071China

Aquaporins(AQPs)are a family of integral membrane proteins that have been shown to be important for osmoregulation in many *** identify potential stress resistance-related aqp genes in salinity adaptation of the roughskin sculpin Trachidermus fasciatus,we investigated the time-course expression dynamics of seven aquaporin genes(aqp1,4,7,8,10,11 and 12)in three osmoregulatory tissues(kidney,gill and intestine)and one metabolic tissue(liver).The fish were subjected to two different acute osmotic treatments(seawater-tofreshwater transfer respectively achieved in 1 h and 24 h,namely.e-acute and acute group).The expression profiling of the seven aqp genes were performed using quantitative real-time PCR(qRT-PCR).At the time of all sampling time points(0 h,12 h,24 h and 48 h),no expression of aqp4 was found in the gill,liver and intestine;no expression of aqp7 was found in the gill and *** differences of aqp expression were determined in the four target tissues,and the mRNA levels were largely variable among gene members and *** patterns of the time-course expression were detected in most of the aqp genes in *** between the two acute groups,except that only one gene(aqp12)in the kidney and three genes(aqp7,aqp8 and aqp10)in the intestine revealed different expression *** results suggest that the expression response of aqp genes was similar under osmotic changes with different rates.

关键词： Trachidermus fasciatus aquaporin salinity changes stress response gene expression

Oxidation Modification of Polyacrylonitrile-Based Carbon Fiber and Its electro-Chemical Performance as Marine electrode for electric Field Test

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Journal of Ocean University of China 2020年第2期19卷 361-368页

作者： ZAI Xuerong LIU ang TIAN yuhua CHAI Fanggang FU yubin College of Chemistry and Chemical engineering Ocean University of ChinaQingdao 266100China School of Materials Science and engineering Ocean University of ChinaQingdao 266100China

A novel sensor for ocean electric field testing has been fabricated by polyacrylonitrile-based on carbon fibers with electro-chemical *** surface profile characteristics of the carbon fibers were characterized by scanning electron microscope,Fourier transform infrared spectra and contact *** voltammetry and Tafel curves have been used to study its electro-chemical *** identical electrodes in sea water as the electric field sensor will swiftly respond to applied electric field which causes positive and negative ions to move in opposite direction,resulting in a electric potential difference(Δe).Test result indicates that the offset potential is typically below 1 m V with a drift of 60-170μVd^-*** self noise level is 1.07 nV√Hz^(1/2)@1 *** electric field response indicates that the modified electrode pair shows better response to AC sine signal of amplitude and frequency(5 mV and 1 mHz)respectively than its *** electric field response model of the modified electrodes is creatively presented according to its electric double layer capacitance and Faraday *** advantages of the carbon fiber electric field electrode will make it have potential application prospect.

关键词： carbon fiber electrode electro-chemical oxidation modification electro-chemical performance electric field response electric field test

Nuclear DNA damages generated by reactive oxy.en molecules (ROS) under oxidative stress and their relevance to human cancers, including ionizing radiation-induced neoplasia part I: Physical, chemical and molecular biology aspects

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Radiation Medicine and Protection 2020年第4期1卷 140-152页

作者： Robert Nilsson Ning-ang Liu Vinca Institute of Nuclear Sciences Laboratory for Physical ChemistryUniversity of BelgradeSerbia State Key Laboratory of Radiation Medicine and Protection School of Radiation Medicine and ProtectionCollaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education InstitutionsSoochow UniversitySuzhou215123PR China

Oxidative stress(OS)occurs when the production of reactive oxy.en species(ROS)overpowers the body’s natural defence,causing macromolecular *** role of OS in cancer initiation will depend on the likelihood of interaction between short lived ROS and nuclear *** this reason,a description of the physico-chemical properties of the various ROS that have been suggested to be involved is *** damages that are not repaired or mis-repaired during cell proliferation are necessary but not sufficient for cancer *** characteristics of DNA pro-mutagenic lesions and their potential role in cancer induction will be assessed,while stressing quantitative aspects as well as the importance of DNA repair.A low level of a specific DNA adduct can be compensated for by its persistence and high pro-mutagenic *** ionizing radiations generate some of the same oxidative ROS as those involved in OS,the cancer spectrum from whole body radiation exposure should be compared with that associated with OS.A causal link between electromagnetic radiations and human cancer lacks adequate scientific *** knowledge dictates that emphasis should be shifted from oxidative damages of low genotoxicity towards pro-mutagenic lesions induced by reaction products of nitrogen monoxide and complex highly reactive carbonyls,*** the peroxidation of lipids.A common shortcoming when assessing the role of OS in disease is the failure to distinguish between cause and *** the indicators of harmful OS be the result of the pathological condition in question,rather than its cause?Further,little attention has been paid to exposure in food to some of the same ROS(*** carbonyl compounds),as are generated endogenously by *** have the simultaneous presence of an ubiquitous high background of potent pro-carcinogenic DNA adducts which are not generated by ROS been taken into account.

关键词： Oxidative stress Cancer DNA adducts Ionizing radiation

Discovering Overlapping Communities by Clustering Local Link Structures

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Chinese Journal of electronics 2017年第2期26卷 430-434页

作者： TAO Haicheng Wang youquan WU Zhi'ang BU Zhan CAO Jie College of Computer Sci.and eng. Nanjing University of Science and Technology

Recent advances point out that the existing community detection methods commonly face two challenges:incorrect base-structures and incorrect membership of *** overcome both problems,a Local link structure(LLS) clustering based method for overlapping community detection is *** extend the similarity of a pair of links to a group of links named LLS,and thus transform mining LLSs as a pattern mining *** prove that LLS with an appropriate threshold can filter weak-ties in the form of bridge and local bridge with its span being larger than 3.A compositive framework is presented for overlapping community detection based on LLS mining and *** experiments on both synthetical and real-world networks demonstrate that our method has advantage over six existing methods on discovering higher quality communities.

关键词： Complex network Overlapping community detection Weak-ties Hy.ergraph Clustering

The Corrected Finite Volume element Methods for Diffusion equations Satisfying Discrete extremum Principle

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Communications in Computational Physics 2022年第10期32卷 1437-1473页

作者： ang Li Hongtao yang yonghai Li Guangwei yuan School of Mathematics Jilin UniversityChangchun 130012JilinChina Institute of Applied Physics and Computational Mathematics Fenghaodong RoadHaidian DistrictBeijing 100094China

In this paper,we correct the finite volume element methods for diffusion equations on general triangular and quadrilateral ***,we decompose the numerical fluxes of original schemes into two parts,i.e.,the principal part with a twopoint flux structure and the defective *** then with the help of local extremums,we transform the original numerical fluxes into nonlinear numerical fluxes,which can be expressed as a nonlinear combination of two-point *** is proved that the corrected schemes satisfy the discrete strong extremum principle without restrictions on the diffusion coefficient and *** results indicate that the corrected schemes not only satisfy the discrete strong extremum principle but also preserve the convergence order of the original finite volume element methods.

关键词： Diffusion equations finite volume element flux-correct maximum principle