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社保缴费与小微企业产品技术创新关系研究——基于CMES数据调查的实证分析

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中国物价 2024年第6期 58-62页

作者：张海峰张福春中共江门市委党校经济教研室中共海南省委党校经济教研部

本文基于中国小微企业调查数据,实证分析社保缴费对小微企业产品技术创新的影响。结果表明:(1)社保缴费能够促进小微企业的产品技术创新,社保缴费规模越大,小微企业的产品技术创新程度越高;(2)社保缴费对小微企业产品技术创新的作用存... 详细信息

本文基于中国小微企业调查数据,实证分析社保缴费对小微企业产品技术创新的影响。结果表明:(1)社保缴费能够促进小微企业的产品技术创新,社保缴费规模越大,小微企业的产品技术创新程度越高;(2)社保缴费对小微企业产品技术创新的作用存在地区差异,对东部地区小微企业的产品技术创新作用显著,对中西部地区的小微企业作用不显著;(3)社保缴费与规模对产品技术创新的作用存在企业主学历差异,企业主学历为低学历组的小微企业,社保缴费与规模对产品技术创新的作用显著,高学历组作用不显著。

关键词：社保缴费小微企业产品技术创新 CMES

First-principles study on electronic structures and optical properties of the single-walled (n, 0) ZnO nanotubes

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Science China(Physics,Mechanics & Astronomy) 2013年第4期56卷 706-712页

作者： DONG JunTang zhang fuchun zhang WeiHu zhang ZhiYong College of Physics and Electronic Information Yanan University Information Science and Technology Institution Northwest University

Using the first-principles calculations, we studied the geometric structures, electronic structures and optical properties of the single-walled (n, 0) ZnO nanotubes (NTs). The calculated results show that all the bind energies of the single-walled (n,0) ZnO NTs are of negative values, which indicate that the ZnO NTs can exist stably as single-walled NTs. While the calculated results of electronic structure indicate that the single-walled (n,0) ZnO NTs are a type of direct wide band-gap semiconductor materials, the whole valence bands are spread and drift to low-energy direction with the increase of the NT diameter. The defect energy levels caused by quantum size and surface effects emerge on the top of the valence bands. Furthermore, the calculated results of optical properties reveal that the dielectric peaks have a blue shift and the edge of absorption band corresponds to ultraviolet band with the decrease of the NT diameter. The single-walled (n, 0) ZnO NTs can be applied to ultraviolet semiconductor systems.

关键词： ZnO first-principles nanotube properties

Exact solution to a class of generalized Kitaev spin-1/2 models in arbitrary dimensions

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Science China(Physics,Mechanics & Astronomy) 2020年第4期63卷 125-135页

作者： JianJian Miao HuiKe Jin fuchun zhang Yi Zhou Kavli Institute for Theoretical Sciences University of Chinese Academy of SciencesBeijing 100190China Department of Physics Zhejiang UniversityHangzhou 310027China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100190China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China Beijing National Laboratory for Condensed Matter Physics&Institute of Physics Chinese Academy of SciencesBeijing 100190China

We construct a class of exactly solvable generalized Kitaev spin-1/2 models in arbitrary dimensions, which is beyond the category of quantum compass models. The Jordan-Wigner transformation is employed to prove the exact solvability. An exactly solvable quantum spin-1/2 model can be mapped to a gas of free Majorana fermions coupled to static Z2 gauge fields. We classify these exactly solvable models according to their parent models. Any model belonging to this class can be generated by one of the parent models. For illustration, a two dimensional(2D) tetragon-octagon model and a three dimensional(3D) xy bond model are studied.

关键词： exactly solvable models Kitaev honeycomb model quantum spin liquid

A first-principles study of the size-dependent electronic properties of SiC nanotubes

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Science China(Physics,Mechanics & Astronomy) 2010年第7期53卷 1333-1338页

作者： zhang WeiHu zhang fuchun zhang ZhiYong LU ShuYuan YANG YanNing Xi’an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi’an 710068China Graduate University of Chinese Academy of Sciences Beijing 100049China College of Physics and Electronic Information Yan’an UniversityYan’an 716000China College of Information Science and Technology Northwest UniversityXi’an 710127China Department of Telecommunications Xi’an Institute of Posts and TelecommunicationsXi’an 710121China

We investigate the structural and electronic properties of SiC nanotubes(NTs) with hexagonal cross sections by a first-principles calculation using plane-wave ultra-soft pseudo-potential technology based on the density-functional *** results reveal that surface-layer C and Si atoms relax significantly upon decreasing the tube-wall thickness because of surface-size and quantum-size *** also find that all relaxed SiC NTs stay stably on the nanoscale because of an admixture of sp2 and sp3 hybridization between C and Si atoms and a strong covalent,and that the band gap tends to decrease with increasing tube-wall *** calculations further indicate that both C and Si atoms on the inner and outer surface of SiC NTs contribute to defect states at the top of the valence band and at the bottom of the conduction *** results provide reference information for a thorough understanding of the properties of SiC nanostructures and also enable more precise monitoring and control of the growth of SiC nanostructures.

关键词： density function theory SiC nanotube electronic properties quantum-size effects

Computational exploration and screening of novel Janus MA2Z4 (M = Sc–Zn, Y–Ag, Hf–Au;A=Si, Ge;Z=N, P) monolayers and potential application as a photocatalyst

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Frontiers of physics 2022年第6期17卷 51-61页

作者： Weibin zhang Woochul Yang Yingkai Liu Zhiyong Liu fuchun zhang College of Physics and Electronics Information Yunnan Key Laboratory of Opto-Electronic Information TechnologyKey Laboratory of Advanced Technique&Preparation for Renewable Energy Materials-Ministry of EducationYunnan Normal UniversityKunming 650500China College of Physics and Electronic Information Yan’an UniversityYan’an 716000China Department of Physics Dongguk UniversitySeoul 04620Republic of Korea

By high-throughput calculations,13 thermally and environmentally stable Janus MA_(2)Z_(4) monolayers were screened from 104 types of *** 13 stable monolayers have very high charge carrier concentrations(×10^(15) cm^(–2)),which are better than those of the well-known graphene and TaS_(2).Because of their excellent conductivity,the 6 monolayers with band gaps less than 0.5 eV are identified as potential electrode materials for hydrogen evolution reaction *** potential applications as photoelectric or photocatalytic materials,bandgaps(Eg-HSE)higher than 0.5 eV remained,which resulted in 7 potential *** on optical absorption analysis in the visible-light range,H-HfSiGeP_(4) and HMoSiGeP_(4) have higher absorption ability and optical conductivity,which is quite impressive for optoelectronic,solar cell device,and photocatalysis ***,the transmittance coefficient of Janus MA_(2)Z_(4) monolayers is approximately 70%–80%in the visible-light range,which implies that these monolayers show good light *** potential applications as photocatalysts,the redox potential and charge effective mass analysis indicate that H-HfSiGeP_(4),HMoSiGeP_(4),T-ScSiGeN_(4),and T-ZrSiGeN_(4) are suitable photocatalysts for CO_(2) reduction *** high-throughput identification,13 types of new and stable Janus MA2Z4 monolayers were explored,and the basic properties and potential applications were investigated,which can reduce the time for experiments and provide basic data for the material genome initiative.

关键词： Janus MA2Z4 high-throughput identification charge carrier concentration electronic structure optical properties

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企业家创新精神与小微企业创新关系研究

新乡学院学报 2024年第7期41卷 28-36,48页

作者：张海峰张福春董法尧中共江门市委党校经济教研室广东江门529000 中共海南省委党校经济教研部海南海口571101 中共成都市委党校马克思主义学院四川成都610110

小微企业创新能力的提升对于促进就业、科技进步、增强经济活力具有不可替代的作用。以中国小微企业调查数据(CMES)为研究样本,通过构建二元Logistic模型,实证分析企业家创新精神对小微企业创新的多维度影响,并进一步探究企业地区、品... 详细信息

小微企业创新能力的提升对于促进就业、科技进步、增强经济活力具有不可替代的作用。以中国小微企业调查数据(CMES)为研究样本,通过构建二元Logistic模型,实证分析企业家创新精神对小微企业创新的多维度影响,并进一步探究企业地区、品牌及创新程度异质性对小微企业创新促进效应的影响差异。研究结果表明:企业家创新精神对小微企业的产品技术创新、其他类型创新、专利申请均有显著促进作用,但是从匹配估计结果看促进效应存在高估的情况;企业家创新精神对小微企业创新的促进影响并不存在显著地区差异,与有自有品牌的小微企业相比,无自有品牌小微企业企业家创新精神对产品技术创新、其他创新的促进效应更大,但对专利申请的促进效应并不显著;创新投入对不同程度的企业创新均产生正向影响,而且随着创新程度的提高,创新投入的积极促进效应也相应增大。研究结果为精准解决小微企业创新面临的问题和困境提供证据,同时也为制定小微企业创新发展政策,因地制宜、分类施策提供理论依据。

关键词：企业家创新精神小微企业企业创新

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基于YOLOv7的交通目标检测算法研究

计算机测量与控制 2024年第4期32卷 74-80页

作者：王沛雪张富春董晨乐延安大学物理与电子信息学院陕西延安716000

针对交通场景中,由于光照、遮挡、目标小以及背景复杂等因素导致目标检测精度低,易出现漏检和误检问题的情况,提出了一种基于YOLOv7的交通目标检测算法;该算法在主干网络中融入多头注意力机制,以增强网络特征学习能力,从而更好地捕获数... 详细信息

针对交通场景中,由于光照、遮挡、目标小以及背景复杂等因素导致目标检测精度低,易出现漏检和误检问题的情况,提出了一种基于YOLOv7的交通目标检测算法;该算法在主干网络中融入多头注意力机制,以增强网络特征学习能力,从而更好地捕获数据和特征内部的相关性;在YOLOv7颈部网络引入协调注意力模块(CA),将位置信息嵌入到注意力机制中,忽略无关信息的干扰,以增强网络的特征提取能力;增加一个多尺度检测网络,以增强模型对不同尺度目标的检测能力;将CIoU损失函数更改为SIoU函数,以减少模型收敛不稳定问题,提高模型的鲁棒性;实验结果表明,改进的算法在BDD100K公开数据集上的检测精度和速度分别达到了59.8%mAP和96.2 FPS,相比原算法检测精度提高了2.5%;这表明改进的算法在满足实时性要求的同时,具备良好的检测精度,适用于复杂情况下的交通目标检测任务。

关键词：交通目标检测 YOLOv7网络注意力机制浅层网络检测层 SIoU损失函数

The Motion Planets Detection and Tracking Algorithm Based on Gestalt Principle

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Chinese Journal of Electronics 2018年第4期27卷 808-812页

作者： QIU Shi TANG Ying zhang Wenbo FENG Jun zhang fuchun LI Chen Xi'an Institute of Optics and Precision Mechanics of CAS Chengdu University of Technology College of Information Science & Technology School of Electronic Engineering Xidian University School of Information Science and Technology Engineering Northwestern University Department of Aviation Theory Aviation University of Air Force Institute of Deep-sea Science and Engineering Chinese Academy of Sciences

The moving planets have a few of pixels which can lead to lacking enough image characteristics when tracking them. So we propose the motion planets detection and tracking algorithm based on gestalt principle. We structure Gaussian mixture model to detect the motion area from the visual cognition perspective, and use astronomy images graphics characteristics to confirm the planet position. Then we propose space-time fusion model for tracking planet. All the experiments use 1000 16-bitframe images of wide view CCD camera which contain 5684 motion planets in total. The results show that our algorithm reaches an accuracy of 94% and has robustness.

关键词： The moving planets Gestalt principle Tracking

153例急性期和慢性期布鲁氏菌病患者临床表现、实验室特征及治疗比较

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中华地方病学杂志 2024年第5期43卷 398-403页

作者：杨慧勤郑海鹏陈旭丹谭颖张复春李凌华王建广州医科大学附属市八医院感染病中心，广州510440

目的了解急性期和慢性期布鲁氏菌病(简称布病)患者的临床表现、实验室特征及治疗情况。方法回顾性收集2012-2022年广州医科大学附属市八医院收治的153例布病患者临床资料,包括一般资料、流行病学特征、临床表现、实验室检查结果、影像... 详细信息

目的了解急性期和慢性期布鲁氏菌病(简称布病)患者的临床表现、实验室特征及治疗情况。方法回顾性收集2012-2022年广州医科大学附属市八医院收治的153例布病患者临床资料,包括一般资料、流行病学特征、临床表现、实验室检查结果、影像学检查结果、治疗及预后情况。按病程<180 d和≥180 d分为急性期组和慢性期组,对比分析两组患者临床资料。结果共纳入布病患者153例,其中急性期组119例、慢性期组34例。年龄为(46.2±13.8)岁,男性115例(75.2%)、女性38例(24.8%),85例(55.6%)患者为职业接触。90例(58.8%)患者出现并发症,慢性期组并发症发生率高于急性期组[76.5%(26/34)比53.8%(64/119),χ^(2)=5.62,P=0.018]。临床表现主要为发热和关节痛,分别有128例(83.7%)和124例(81.0%)。急性期组发热发生率高于慢性期组[87.4%(104/119)比70.6%(24/34),χ^(2)=5.46,P=0.019],而关节痛发生率低于慢性期组[77.3%(92/119)比94.1%(32/34),χ^(2)=4.83,P=0.027]。实验室检查中,血培养阳性率为59.5%(91/153),急性期组血培养阳性率高于慢性期组[67.2%(80/119)比32.4%(11/34),P<0.05];急性期组降钙素原(PCT)升高发生率[58.6%(58/99)比24.1%(7/29),χ^(2)=10.65,P=0.001]和肝功能异常发生率均高于慢性期组[33.9%(40/118)比15.2%(5/33),χ^(2)=4.33,P=0.037]。影像学检查中,61例(39.9%)患者发生骨质破坏,慢性期组骨质破坏发生率高于急性期组[55.9%(19/34)比35.3%(42/119),χ^(2)=4.68,P=0.031]。所有患者均使用抗生素治疗,急性期、慢性期组使用抗生素种类的中位数分别为3、4种。总体药物不良反应发生率为5.2%(8/153),治疗后65例(42.5%)痊愈、70例(45.8%)好转、18例(11.8%)未愈。结论布病患者的主要临床表现为发热和关节痛,并发症发生率较高,均采用联合抗感染治疗。急性期患者发热、血培养阳性、PCT升高、肝功能异常发生率较高,慢性期患者并发症、关节痛、骨质破坏发生率较高。

关键词：布鲁氏菌病临床表现实验室特征治疗

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