检索结果-南通市图书馆

Adaptive Power Control for mutual Interference Avoidance in Industrial Internet-of-Things

在线全文

学校读者我要写书评

暂无评论

China Communications 2016年第S1期13卷 124-131页

作者： zheng Tao QIN yajuan ZHANG Hongke KUO Syyen School of Electronics and Information Engineering Beijing Jiaotong University Department of Electrical Engineering National Taiwan University

With the vigorous development of the Internet of Things and 5G technology, such as machine-to-machine and device-todevice, all kinds of data transmission including environmental monitoring and equipment control strengthens the key role of wireless sensor networks in the large-scale wireless communication system. However, especially in the complex industrial wireless applications, the low utilization efficiency of the limited wireless radio resource enhances the coexistence problem between heterogeneous networks. In this paper, from the severe mutual interference point of view, a mathematical model regarding cumulative interferences in the industrial wireless sensor networks is described. Then, from the perspective of mutual interference avoidance, an adaptive power control scheme is proposed in order to handle the normal communication needs on both the primary link and the secondary link. At last, nonlinear programming is taken to solve the corresponding optimization problem. Some typical analyses are given to verify the effectiveness of the proposed scheme on optimizing the tradeoff between the system throughput and energy consumption. Especially, the energy-efficiency of the novel scheme for Industrial Internet of Things is also analysed. Results show that the proposed power control is efficient. The throughput could be enhanced and the energy consumption could be reduced with the guarantee of mutual interference avoidance.

关键词： industrial wireless sensor networks optimization power control mutual interference

在线全文

学校读者我要写书评

暂无评论

基于单体石墨纤维的场发射特性研究

人工晶体学报 2021年第5期50卷 866-870页

作者：霍海波郑亚娟麻华丽董子华李倩倩李明玉丁佩曾凡光郑州航空工业管理学院材料学院郑州450015

利用化学气相沉积(CVD)法,以甲烷为碳源在管式炉中合成了单体石墨纤维(MGF)。选取长度为3.426 mm,顶端球面半径为11.26μm的单体石墨纤维直立于圆铜片上作为阴极,以导电ITO玻璃作为阳极,采用二极管结构在真空室中进行直流场发射测试,证... 详细信息

利用化学气相沉积(CVD)法,以甲烷为碳源在管式炉中合成了单体石墨纤维(MGF)。选取长度为3.426 mm,顶端球面半径为11.26μm的单体石墨纤维直立于圆铜片上作为阴极,以导电ITO玻璃作为阳极,采用二极管结构在真空室中进行直流场发射测试,证实MGF的开启场强为0.4775 V/μm。基于有限元仿真软件ANSYS进行电磁场分析,计算了MGF在不同电压下的有效发射面积。结果表明,当电压为5.36 kV时,MGF达到最大发射面积为796.226μm^(2),在实验测量电压范围内,平均发射电流密度可以达到46.069 A/cm^(2),单体石墨纤维具有良好的场发射特性。

关键词：单体石墨纤维场发射有效发射面积电流密度场增强因子

在线全文

学校读者我要写书评

暂无评论

性激素在视神经疾病中的研究进展

新医学 2019年第11期50卷 801-804页

作者：李艳霞聂圣琼牛灵芝郑雅娟吉林大学第二医院眼科中心

近年来,性激素在视神经疾病中所起的作用越来越受到关注。例如雌激素可减轻青光眼患者的视神经损伤并且有一定程度的降眼压作用,血清孕酮水平的降低与非动脉炎性前部缺血性视神经病变密切相关,男性相对更易患Leber遗传性视神经病变,以... 详细信息

近年来,性激素在视神经疾病中所起的作用越来越受到关注。例如雌激素可减轻青光眼患者的视神经损伤并且有一定程度的降眼压作用,血清孕酮水平的降低与非动脉炎性前部缺血性视神经病变密切相关,男性相对更易患Leber遗传性视神经病变,以及多发硬化相关性视神经炎的复发率存在性别差异等,提示性激素在视神经疾病中扮演重要角色。该文就性激素在视神经疾病中的作用及其机制进行综述。

关键词：性激素视神经疾病青光眼 Leber遗传性视神经病变非动脉炎性前部缺血性视神经病变多发硬化相关性视神经炎

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

血液透析患者血钙浓度的调查分析和护理

中国医药指南 2021年第36期19卷 14-16页

作者：郭秀蝶张亚真郑雅娟林晨芳吴群福建医科大学附属漳州市医院血液透析室福建漳州363000

目的回顾性分析单中心维持性血液透析患者钙浓度,调查低钙血症、高钙血症的患病率、诊疗和护理措施。方法本研究为单中心回顾性研究。分析福建医科大学附属漳州市医院血透室2019年5月血液透析266例患者钙浓度检查的结果。并分析其诊疗... 详细信息

目的回顾性分析单中心维持性血液透析患者钙浓度,调查低钙血症、高钙血症的患病率、诊疗和护理措施。方法本研究为单中心回顾性研究。分析福建医科大学附属漳州市医院血透室2019年5月血液透析266例患者钙浓度检查的结果。并分析其诊疗和护理措施。同时调查患者自行购买钙制剂的比例。结果本研究纳入266例的患者资料。患者血液透析前的平均血钙水平为2.08 mmol/L(1.51~2.87 mmol/L),其中146例患者低钙血症,1例患者高钙血症。上述患者均无明显低钙或高钙的相关症状。89例口服钙制剂治疗,25例维生素D制剂治疗,10例口服西那卡塞治疗,19例口服开同治疗。3例患者自行购买钙制剂。护理措施包括:饮食宣教、用药指导等。结论血液透析患者合并钙代谢紊乱的发生率高,二者均可无症状。严格的掌握钙制剂、维生素D制剂和开同应用,并加强护理宣教可以有效控制高钙血症。

关键词：血液透析患者血钙浓度调查分析护理

Multi-Object Detection of Chinese License Plate in Complex Scenes

在线全文

学校读者我要写书评

暂无评论

Computer Systems Science & Engineering 2021年第1期36卷 145-156页

作者： Dan Liu yajuan Wu Yuxin He Lu Qin Bochuan zheng School of Computer Science China West Normal UniversityNanchong637002China School of Mathematics and Information China West Normal UniversityNanchong637002China Internet of Things Perception and Big Data Analysis Key Laboratory of Nanchong China West Normal UniversityNanchong637002China

Multi-license plate detection in complex scenes is still a challenging task because of multiple vehicle license plates with different sizes and classes in the images having complex *** edge features of high-density distribution and the high curvature features of stroke turning of Chinese character are important signs to distinguish Chinese license plate from other *** accurately detect multiple vehicle license plates with different sizes and classes in complex scenes,a multi-object detection of Chinese license plate method based on improved YOLOv3 network was proposed in this *** improvements include replacing the residual block of the YOLOv3 backbone network with the Inception-ResNet-A block,imbedding the SPP block into the detection network,cutting the redundant Inception-ResNet-A block to suit for the multi-license plate detection task,and clustering the ground truth boxes of license plates to obtain a new set of anchor boxes.A Chinese vehicle license plate image dataset was built for training and testing the improved network,and the location and class of the license plates in each image were accurately *** dataset has 62,153 pieces of images and 4 classes of China vehicle license plates,almost images have multiple license plates with different *** demonstrated that the multilicense plate detection method obtained 83.4%mAP,98.88%precision,98.17%recall,98.52 F1 score,89.196 BFLOPS and 22 FPS on the test dataset,and whole performance was better than the other five compared networks including YOLOv3,SSD,Faster-RCNN,EfficientDet and RetinaNet.

关键词： Chinese vehicle license plate multiple license plate multi-object detection Inception-ResNet-A spatial pyramid pooling

基于微信平台的口腔健康指导对口腔正畸治疗患者遵医行为和牙周健康的影响

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国美容医学 2023年第5期32卷 171-175页

作者：魏雅静李颖郑亚娟刘丹张明李利利北京市大兴区人民医院口腔科北京102600

目的:探讨基于微信平台的口腔健康指导对口腔正畸治疗患者遵医行为和牙周健康的影响。方法:选择笔者医院2020年6月-2021年6月需口腔正畸治疗的150例患者为研究对象,依据随机、平行、对照的原则,按随机数字表法分为观察组和对照组各75例... 详细信息

目的:探讨基于微信平台的口腔健康指导对口腔正畸治疗患者遵医行为和牙周健康的影响。方法:选择笔者医院2020年6月-2021年6月需口腔正畸治疗的150例患者为研究对象,依据随机、平行、对照的原则,按随机数字表法分为观察组和对照组各75例。观察组采用基于微信平台的口腔健康指导干预,对照组常规床旁口腔健康指导干预。评价两组患者遵医行为、口腔健康知识与正畸治疗知识掌握情况、菌斑指数(Plaque index,PLI)、牙龈指数(Gingival index,GI)、龈沟出血指数(Gingival sulcus bleeding index,SBI)及并发症情况。结果:干预前,两组患者遵医行为评分、口腔健康知识与正畸治疗知识掌握情况评分、PLI、GI、SBI组间比较,差异无统计学意义(P>0.05);干预后,两组患者遵医行为、口腔健康知识与正畸治疗知识掌握情况各评分均升高,且观察组各评分均高于对照组,差异均有统计学意义(P<0.05);干预后,两组患者PLI、GI、SBI各指标评分均降低,且观察组各指标评分均低于对照组,差异均有统计学意义(P<0.05);观察组各项并发症发生率均低于对照组(P<0.05)。结论:基于微信平台的口腔健康指导方式应用于正畸治疗患者护理中,可有效提高患者的遵医行为及对相关知识的掌握程度,能有效改善患者口腔及牙周状态,降低口腔正畸并发症,具有一定的临床应用价值。

关键词：微信平台口腔指导口腔正畸牙周健康遵医行为

维普期刊数据库博看期刊

A Genetic Algorithm for Optimizing Yaw Operation Control in Wind Power Plants

在线全文

学校读者我要写书评

暂无评论

Fluid Dynamics & Materials Processing 2022年第3期18卷 511-519页

作者： Lisha Shang yajuan Jia Liming zheng Erna Shi Min Sun Xi’an Traffic Engineering Institute Xi’an710300China

A genetic algorithm is proposed to optimize the yaw control system used for the stable and efficient operation of turbines in wind power *** particular,the factors that produce yaw static deviation are ***,the sought optimization method for the yaw static deviation of the wind turbine is implemented by using a lidar wind meter in the engine room in order to solve the low accuracy problem caused by yaw static *** is shown that fuzzy control can overcome problematic factors such as the randomness of wind direction and track the change of wind direction *** control implementation is simple,as only the voltage and current of the generator need to be measured.

关键词： Genetic algorithm yaw control system power control the control strategy

Formamidinium Lead Bromide (FAPbBr_3) Perovskite Microcrystals for Sensitive and Fast Photodetectors

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano-Micro Letters 2018年第3期10卷 62-69页

作者： Fengying Zhang Bin Yang Kaibo zheng Songqiu Yang yajuan Li Weiqiao Deng Rongxing He Key Laboratory of Luminescence and Real-Time Analytical Chemistry of Ministry of Education College of Chemistry and Chemical Engineering Southwest University State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics Chinese Academy of Science Department of Chemical Physics and NanoLund Chemical Center Lund University

Because of the good thermal stability and superior carrier transport characteristics of formamidinium lead trihalide perovskite HC(NH_2)_2 PbX_3(FAPbX_3), it has been considered to be a better optoelectronic material than conventional CH_3NH_3-PbX_3(MAPbX_3). Herein, we fabricated a FAPbBr_3 microcrystal-based photodetector that exhibited a good responsivity of 4000 A W-1 and external quantum efficiency up to 106% under one-photon excitation, corresponding to the detectivity greater than 1014 Jones. The responsivity is two orders of magnitude higher than that of previously reported formamidinium perovskite photodetectors. Furthermore, the FAPbBr_3 photodetector's responsivity to two-photon absorption with an 800-nm excitation source can reach 0.07 A W^(-1), which is four orders of magnitude higher than that of its MAPbBr_3 counterparts. The response time of this photodetector is less than 1 *** study provides solid evidence that FAPbBr_3 can be an excellent candidate for highly sensitive and fast photodetectors.

关键词： Formamidinium lead trihalide (FAPbBr3) Perovskite microcrystals Photodetector External quantum efficiency

Plain metallic biomaterials:opportunities and challenges

在线全文

学校读者我要写书评

暂无评论

Regenerative Biomaterials 2023年第1期10卷 140-147页

作者： Jiazhen Zhang Bao Zhai Jintao Gao zheng Li Yufeng zheng Minglong Ma Yongjun Li Kui Zhang yajuan Guo Xinli Shi Bin Liu Guobiao Gao Lei Sun Center for Medical Device Evaluation National Medical Product AdministrationBeijing 100081China Guangdong-Hong Kong-Macao Greater Bay Area Center for Medical Device Evaluation and Inspection of NMPAShenzhen 518045China School of Materials Science and Engineering Peking UniversityBeijing 100871China State Key Laboratory of Nonferrous Metals and Process GRINM Group Corporation Limited(General Research Institute for Nonferrous Metals)Beijing 100088China

The‘plainification of materials’has been conceptualized to promote the sustainable development of *** perspective,for the first time in the field of biomaterials,proposes and defines‘plain metallic biomaterials(PMBs)’with demonstrated research and application case studies of pure titanium with high strength and toughness,and biodegradable,fine-grained and high-purity ***,after discussing the features,benefits and opportunities of PMBs,the challenges are analyzed from both technical and regulatory *** perspectives on PMB-based medical devices are also provided for the benefit of future research,development and commercialization.

关键词： plainification metallic biomaterials regulatory science medical devices pure titanium high-purity magnesium