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城市蔓延对绿色发展的影响

开发研究 2024年第1期 133-143页

作者：柳剑平魏子璇湖北大学商学院武汉430062 湖北省开放经济研究中心武汉430062

基于2006—2019年中国284个城市的面板数据,通过构建双向固定效应模型、门槛效应模型和空间计量模型,实证检验了城市蔓延对绿色发展的影响。研究发现,城市蔓延对绿色发展具有显著的负向影响,且该结论在经过一系列稳健性检验之后依然成立... 详细信息

基于2006—2019年中国284个城市的面板数据,通过构建双向固定效应模型、门槛效应模型和空间计量模型,实证检验了城市蔓延对绿色发展的影响。研究发现,城市蔓延对绿色发展具有显著的负向影响,且该结论在经过一系列稳健性检验之后依然成立;城市蔓延对绿色发展的影响存在异质性,对中东部地区、未开通高铁城市、中小城市的绿色发展的负向影响更加显著;城市蔓延对绿色发展的影响存在单一门槛效应,适度的城市蔓延有助于促进绿色发展水平的提升,但过度的城市蔓延则会对绿色发展产生不利影响。城市蔓延对绿色发展存在显著的空间溢出效应,会抑制本地及邻近地区的绿色发展。基于此,提出科学合理地划定城市蔓延边界、因地制宜地制定城市蔓延调控策略以及加强城市间城市蔓延调控的协同效应等对策建议,以提升城市绿色发展水平。

关键词：城市蔓延绿色发展门槛效应空间溢出效应

临床免疫检验过程中影响检验质量的因素及应对措施探讨

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智慧健康 2024年第3期10卷 163-166页

作者：张欣尉子萱丁晓争刘志敏北京市平谷区中医医院检验科北京101200

目的探讨临床免疫检验过程中影响检验质量的因素及应对措施。方法将2022年1—4月在本院检验科进行免疫检验的300例患者作为研究对象,统计检验质量不合格率,分析影响因素,提出应对措施。结果 300例患者中,共发生检验质量不合格14例(4.6... 详细信息

目的探讨临床免疫检验过程中影响检验质量的因素及应对措施。方法将2022年1—4月在本院检验科进行免疫检验的300例患者作为研究对象,统计检验质量不合格率,分析影响因素,提出应对措施。结果 300例患者中,共发生检验质量不合格14例(4.67%),其中包括患者因素、采血因素、送检因素、检验因素,共4项因素。结论临床免疫检验过程中影响检验质量的因素较多,有患者、采血、送检及检验四个方面,临床应加强检验前后的质量控制,针对相关因素积极防范,有助于提高免疫检验质量,保障检验结果的可靠性。

关键词：免疫检验影响检验质量的因素应对措施

Data and Model Driven Task Offloading Strategy in the Dynamic Mobile Edge Computing System

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Journal of Systems Science & Complexity 2024年第1期37卷 351-368页

作者： DONG Hairong WU wei SONG Haifeng LIU Zhen ZHANG zixuan School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044China School of Electronic and Information Engineering BeiHang UniversityBeijing 100191China CRSC Research&Design Institute Group Co. Ltd.Beijing 100070China

Mobile Edge Computing(MEC)provides communication and computational capabilities for the industrial Internet,meeting the demands of latency-sensitive tasks.Nevertheless,traditional model-driven task offloading strategies face challenges in adapting to situations with unknown network communication status and computational capabilities.This limitation becomes notably significant in complex industrial networks of high-speed railway.Motivated by these considerations,a data and model-driven task offloading problem is proposed in this paper.A redundant communication network is designed to adapt to anomalous channel states when tasks are offloaded to edge servers.The link switching mechanism is executed by the train according to the attributes of the completed task.The task offloading optimization problem is formulated by introducing data-driven prediction of communication states into the traditional model.Furthermore,the optimal strategy is achieved by employing the informer-based prediction algorithm and the quantum particle swarm optimization method,which effectively tackle real-time optimization problems due to their low time complexity.The simulations illustrate that the data and model-driven task offloading strategy can predict the communication state in advance,thus reducing the cost of the system and improving its robustness.

关键词： Data driven model informer mobile edge computing quantum particle swarm optimization task offloading.

Tuning microstructures of TC4 ELI to improve explosion resistance

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Defence Technology（防务技术） 2024年第3期33卷 78-99页

作者： Changle Zhang Yangwei Wang Lin Wang zixuan Ning Guoju Li Dongping Chen Zhi-wei Yan Yuchen Song Xucai Wang School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Science and Technology on Materials under Shock and Impact Beijing 100081China State Key Laboratory of Explosive Science and Technology Beijing Institute of TechnologyBeijing 100081China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China School of Aeronautical Engineering Zhengzhou University of AeronauticsHenan ProvinceZhengzhou 450046China Shanxi Jiangyang Chemical Co. Ltd.Shanxi ProvinceTaiyuan 030041China Shandong Institute of Non-metallic Materials Shandong ProvinceJinan 250031China

A reasonable heat treatment process for TC4 ELI titanium alloy is crucial to tune microstructures to improve its explosion resistance.However,there is limited investigation on tuning microstructures of TC4 ELI to improve explosion resistance.Moreover,the current challenge is quantifying microstructural changes'effects on explosion resistance and incorporating microstructural changes into finite element models.This work aims to tune microstructures to improve explosion resistance and elucidate their anti-explosion mechanism,and find a suitable method to incorporate microstructural changes into finite element models.In this work,we systematically study the deformation and failure characteristics of TC4 ELI plates with varying microstructures using an air explosion test and LS-DYNA finite element modeling.The Johnson-Cook(JC)constitutive parameters are used to quantify the effects of microstructural changes on explosion resistance and incorporate microstructural changes into finite element models.Because of the heat treatment,one plate has equiaxed microstructure and the other has bimodal microstructure.The convex of the plate after the explosion has a quadratic relationship with the charge mass,and the simulation results demonstrate high reliability,with the error less than 17.5%.Therefore,it is feasible to obtain corresponding JC constitutive parameters based on the differences in microstructures and mechanical properties and characterize the effects of microstructural changes on explosion resistance.The bimodal target exhibits excellent deformation resistance.The response of bimodal microstructure to the shock wave may be more intense under explosive loading.The well-coordinated structure of the bimodal target enhances its resistance to deformation.

关键词： Microstructure Finite element modelling Parameter optimization Failure characteristics Explosion resistance

Room-temperature ferromagnetism and piezoelectricity in metalfree 2D semiconductor crystalline carbon nitride

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Nano Research 2024年第6期17卷 5670-5679页

作者： Yong Wang Dingyi Yang wei Xu Yongjie Xu Yu Zhang zixuan Cheng Yizhang Wu Xuetao Gan wei Zhong Yan Liu Genquan Han Yue Hao Wide Bandgap Semiconductor Technology Disciplines State Key Laboratory School of MicroelectronicsAcademy of Advanced Interdisciplinary ResearchXidian UniversityXi’an 710071China Emerging Device and Chip Laboratory Hangzhou Institute of TechnologyXidian UniversityHangzhou 311200China INRS Centre for Energy Materials and Telecommunications1650 Boul.Lionel BouletVarennesQC J3X 1P7Canada National Laboratory of Solid State Microstructures Collaborative Innovation Center of Advanced Microstructures and Jiangsu Provincial Key Laboratory for NanotechnologyNanjing UniversityNanjing 210093China School of Education Jiangsu Open UniversityNanjing 210036China Department of Physics Shaanxi University of Science and TechnologyXi’an 710021China Department of Applied Physical Sciences The University of North Carolina at Chapel HillChapel HillNC 27514USA Key Laboratory of Light Field Manipulation and Information Acquisition Ministry of Industry and Information Technologyand Shaanxi Key Laboratory of Optical Information TechnologySchool of Physical Science and TechnologyNorthwestern Polytechnical UniversityXi'an 710129 China

Two-dimensional(2D)materials that combine ferromagnetic,semiconductor,and piezoelectric properties hold significant potential for both fundamental research and spin electronic devices.However,the majority of reported 2D ferromagnetic-semiconductor-piezoelectric materials rely on d-electron systems,which limits their practical applications due to a Curie temperature lower than room temperature(RT).Here,we report a high-crystallinity carbon nitride(CCN)material based on sp-electrons using a chemical vapor deposition *** exhibits a band gap of 1.8 eV and has been confirmed to possess substantial in-plane and out-of-plane piezoelectricity.Moreover,we acquired clear evidences of ferromagnetic behavior at room temperature.Extensive structural characterizations combined with theoretical calculations reveal that incorporating structural oxygen into the highly ordered heptazine structure causes partial substitution of nitrogen sites,which is primarily responsible for generating room-temperature ferromagnetism and piezoelectricity.As a result,the strain in wrinkles can effectively modulate the domain behavior and piezoelectric potential at room temperature.The addition of RT ferromagnetic-semiconductor-piezoelectric material based on sp-electrons to the family of two-dimensional materials opens up numerous possibilities for novel applications in fundamental research and spin electronic devices.

关键词： crystallinity carbon nitride room-temperature ferromagnetism piezoelectricity magnetic force microscopy density functional theory(DFT)calculations

Interorgan communication in neurogenic heterotopic ossification: the role of brain-derived extracellular vesicles

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Bone Research 2024年第1期12卷 137-152页

作者： weicheng Lu Jianfei Yan Chenyu Wang Wenpin Qin Xiaoxiao Han zixuan Qin Yu wei Haoqing Xu Jialu Gao Changhe Gao Tao Ye Franklin R.Tay Lina Niu Kai Jiao Department of Stomatology Tangdu Hospital&State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration&School of StomatologyThe Fourth Military Medical UniversityXi’anShaanxiChina State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration&National Clinical Research Center for Oral Diseases&Shaanxi Key Laboratory of Stomatology School of StomatologyThe Fourth Military Medical UniversityXi’anShaanxiChina The Dental College of Georgia Augusta UniversityAugustaGAUSA

Brain-derived extracellular vesicles participate in interorgan communication after traumatic brain injury by transporting pathogens to initiate secondary injury.Inflammasome-related proteins encapsulated in brain-derived extracellular vesicles can cross the blood‒brain barrier to reach distal tissues.These proteins initiate inflammatory dysfunction,such as neurogenic heterotopic ossification.This recurrent condition is highly debilitating to patients because of its relatively unknown pathogenesis and the lack of effective prophylactic intervention strategies.Accordingly,a rat model of neurogenic heterotopic ossification induced by combined traumatic brain injury and achillotenotomy was developed to address these two issues.Histological examination of the injured tendon revealed the coexistence of ectopic calcification and fibroblast pyroptosis.The relationships among brain-derived extracellular vesicles,fibroblast pyroptosis and ectopic calcification were further investigated in vitro and in vivo.Intravenous injection of the pyroptosis inhibitor Ac-YVAD-cmk reversed the development of neurogenic heterotopic ossification in vivo.The present work highlights the role of brain-derived extracellular vesicles in the pathogenesis of neurogenic heterotopic ossification and offers a potential strategy for preventing neurogenic heterotopic ossification after traumatic brain injury.

关键词： neurogenic ossification pathogenesis

基于深度神经网络的梯次利用电池健康状态评估

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太阳能学报 2022年第5期43卷 518-524页

作者：魏梓轩韩晓娟李炫华北电力大学控制与计算机工程学院北京102206

随着大量退役电池梯次利用,对退役动力电池健康状态的准确估计是保障电池梯次利用安全高效运行的前提。针对上述问题,提出基于深度神经网络学习的梯次利用电池健康状态评估方法。根据不同循环次数下梯次利用电池充放电性能的差异性,从... 详细信息

随着大量退役电池梯次利用,对退役动力电池健康状态的准确估计是保障电池梯次利用安全高效运行的前提。针对上述问题,提出基于深度神经网络学习的梯次利用电池健康状态评估方法。根据不同循环次数下梯次利用电池充放电性能的差异性,从梯次利用电池物理特性角度挖掘影响梯次利用电池老化特征的主要参数,利用皮尔逊法计算电池老化特征与梯次利用电池健康状态的相关系数,选取较高相关度特征作为深度神经网络的输入,建立基于深度神经网络学习的梯次利用电池健康状态评估模型。通过美国国家航空航天局Ames卓越预测中心的锂离子电池测试数据仿真实例验证了该文方法的有效性。仿真结果表明,与传统神经网络相比,深度神经网络学习可明显提高梯次利用电池健康状态的预测精度,为退役动力电池健康状态评估提供理论依据。

关键词：梯次利用电池神经网络模型电池建模健康状态评估相关性分析电池老化特征

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一种新型微弱ADS-B信号译码算法

无线电工程 2023年第11期53卷 2652-2658页

作者：魏子轩高勇四川大学电子信息学院四川成都610065

广播式自动相关监视(Automatic Dependent Surveillance-Broadcast,ADS-B)广泛应用于空中交通管制,但传播距离远时,ADS-B信号可能十分微弱,不易正确译码。针对此问题,提出低信噪比ADS-B信号的译码算法。该算法计算含噪信号数据块的协方... 详细信息

广播式自动相关监视(Automatic Dependent Surveillance-Broadcast,ADS-B)广泛应用于空中交通管制,但传播距离远时,ADS-B信号可能十分微弱,不易正确译码。针对此问题,提出低信噪比ADS-B信号的译码算法。该算法计算含噪信号数据块的协方差矩阵,利用该矩阵修正信号起始位置的估计值后,再重新确定新的协方差矩阵,对新的矩阵做奇异值分解,得到脉冲波形估计值;利用脉冲波形估计值与标准脉冲波形分别进行初步译码,并对低置信度比特进行循环冗余纠错。理论计算和仿真表明,在噪声为加性高斯白噪声且前导脉冲位置确定时,该译码算法能明显提高信号的正确接收概率。实验表明,当实测微弱信号的功率为-99 dBm时,正确接收概率为97.9%。

关键词：广播式自动相关监视奇异值分解微弱信号译码算法

利用CRISPR/Cas9在人类黑色素瘤细胞中编辑MC1R与功能分析

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遗传 2022年第7期44卷 581-590页

作者：张充魏子璇王敏陈瑶生何祖勇中山大学生命科学学院有害生物控制与资源利用国家重点实验室广州510006

MC1R(melanocortin 1 receptor)基因编码黑皮质素1型受体,它在配体α-黑素细胞刺激素(α-melanocyte stimulating hormone,α-MSH)的刺激下,可促进细胞内cAMP(cyclic adenosine monophosaphate)的生成,从而激活PKA(protein kinase A system)信号通路,促进黑色素合成调控的关键转录因子–小眼畸形相关转录因子(microphthalmia-associated transcription factor,MITF),以及限速酶–酪氨酸酶(tyrosinase,TYR)的表达,进而调控真黑素和褐黑素的合成,影响动物的毛色表型。有研究表明,杜洛克猪(Susscrofa domestica)MC1R蛋白第6个跨膜结构域(transmembrane domain 6,TM6)发生了A243T突变,该突变可能影响MC1R蛋白生物学功能,被认为是导致杜洛克猪红毛表型的主要因素,然而却一直未被验证过。因此,本研究以单链寡核苷酸(single-stranded oligo-deoxyribonucleotides,ssODN)作为同源重组模板,利用CRISPR/Cas9技术在人类黑色素瘤细胞系SK-MEL-2中引入MC1R基因的c.727G>A(A243T)突变,以分析其对MC1R功能的影响。结果表明ssODN发生同源重组的效率可达10%。通过对共转染ssODN和CRISPR/Cas9表达载体的细胞进行筛选和培养,获得6个单克隆细胞株,进行测序鉴定,结果未能筛选到发生预期突变的单克隆细胞株,所有单克隆细胞株皆在目标位点周围出现突变。对转染后的细胞群进行功能分析,结果发现其cAMP信号强度、MITF基因和TYR基因表达量均显著低于未转染的细胞,表明编辑MC1R可影响细胞的黑色素合成功能。本研究为深入分析MC1R突变影响动物毛色提供了进一步的参考。

关键词： MC1R 基因定点突变 CRISPR/Cas9 A243T