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Jitter analysis of real-time services in IEEE 802.15.4 WSNs and wired IP concatenated networks

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The Journal of china Universities of Posts and Telecommunications 2016年第4期23卷 1-8页

作者： Na Fei CHI Xuefen Dong Wen Yu Haifeng School of Communication Engineering Jilin University

It is challenging and significant to explore the impacts of non-real-time services on real-time services from the perspective of jitter. Most of current researches on jitter made too many mathematical hypotheses on networks and traffic. This paper puts forward a tandem queuing model to characterize the real communication scenario where heterogeneous services are served by IEEE 802.15.4 wireless sensor networks（WSNs）, and then the packets served successfully are fed to Internet protocol（IP） networks. By analyzing the contention access processes in IEEE 802.15.4 WSNs, the authors derive the departure processes of the two types of services, i.e., the arrival processes of IP networks. The IP network is modeled as a queuing system, in which the real-time service is forwarded accompanied by the non-real-time service. Investigating the jitter of real-time services is intractable. Therefore, this paper abstracts this problem as a dynamic queuing system evolving on a dynamic time interval. Referring the transient analysis method（TAM）, this paper obtains the queue length in a random time interval which is scaled by the arrival of real-time services. Queue length evolution is closely connected with the jitter. Benefiting from the derivation in probability generation domain, the jitter of real-time services is obtained.

关键词： jitter heterogeneous M2M services transient analysis IEEE 802.15.4 WSNs IP networks

Research on mobile phone swaying and receiving position in optical camera communication

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Optoelectronics Letters 2022年第2期18卷 85-90页

作者： JIANG Keyu CHI Xuefen JI Fenglei LI Shuai Department of Communications Engineering Jilin UniversityChangchun 130012China

Optical camera communication(OCC) is gaining increasing attention in researches. However, applying it to a real-world scenario may encounter many practical problems, such as the communication device may sway or there may be a position offset between the camera and the light source, which may distort the stripes and make the message unreceivable. To this end, we propose pilot-based stripe area estimation(P-SAE) decoding algorithm, and design a pixels rearrangement(PR) scheme and stripes separation logic decision method(SSLD) to improve the decoding performance under sway or receiving position offset. Finally, we build a practical OCC system and carry out experiments to verify the effectiveness of the decoding algorithm. Experimental results show that the lightweight decoding algorithm can resist the impact of smartphone sway and receiving position offset on decoding accuracy.

关键词： communication offset camera

The Research of Indoor Positioning Based on Visible Light Communication

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china Communications 2015年第8期12卷 85-92页

作者： WANG Chunyue WANG Lang CHI Xuefen LIU Shuangxing SHI Wenxiao DENG Jing College of Communication Engineering Jilin University University of North Carolina at Greensboro

The key techniques in indoor positioning based on visible light communication and the state of the art of this research were surveyed. First, the significance of indoor positioning based on visible light communication from two aspects of the limitations of current indoor positioning technology and the advantages of visible light communication was discussed; And then, the main four technology of indoor positioning based on visible light communication were summarized and the triangulation of RSS method and the principle of image positioning were introduced in detail; Next, the performance characteristics of various typical algorithms were compared and analyzed; In the end, several suggestions on future research of indoor positioning based on visible light communication were given.

关键词：可见光通信室内定位定位技术形象定位三角测量性能特点阳离子 S方法

Multi-Hop Routing Optimization Method Based on Improved Ant Algorithm for Vehicle to Roadside Network

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Journal of Bionic Engineering 2014年第3期11卷 490-496页

作者： Hao Dong Xiaohui Zhao Liangdong Qu xuefen chi Xinyu Cui College of Communication Engineering Jilin University Changchun 130000 P. R. China

This paper proposes a route optimization method to improve the performance of route selection in Vehicle Ad-hoc Network （VANET）. A novel bionic swarm intelligence algorithm, which is called ant colony algorithm, was introduced into a traditional ad-hoc route algorithm named AODV. Based on the analysis of movement characteristics of vehicles and according to the spatial relationship between the vehicles and the roadside units, the parameters in ant colony system were modified to enhance the performance of the route selection probability rules. When the vehicle moves into the range of several different roadsides, it could build the route by sending some route testing packets as ants, so that the route table can be built by the reply information of test ants, and then the node can establish the optimization path to send the application packets. The simulation results indicate that the proposed algorithm has better performance than the traditional AODV algorithm, especially when the vehicle is in higher speed or the number of nodes increases.

关键词： multi-hop routing optimization ant colony algorithm VANET bionic swarm intelligence algorithm

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上颌骨性扩弓器对成年女性眼眶容积的评价

华西口腔医学杂志 2022年第3期40卷 314-319页

作者：史晓扬林雪芬马驰陈沐寒刘东旭山东大学齐鲁医学院口腔医学院·口腔医院正畸科山东省口腔组织再生重点实验室山东省口腔生物材料与组织再生工程实验室济南250012

目的评价上颌骨性扩弓器(MSE)治疗成年女性上颌骨宽度不足(MTD)对眼眶容积及眶周骨骼间宽度的影响。方法选取采用MSE治疗的MTD成年女性患者20例,年龄为(22.60±6.29)岁。分别于扩弓前(T0)和扩弓结束3周内(T1)拍摄锥形束CT,将数据导入Mim... 详细信息

目的评价上颌骨性扩弓器(MSE)治疗成年女性上颌骨宽度不足(MTD)对眼眶容积及眶周骨骼间宽度的影响。方法选取采用MSE治疗的MTD成年女性患者20例,年龄为(22.60±6.29)岁。分别于扩弓前(T0)和扩弓结束3周内(T1)拍摄锥形束CT,将数据导入Mimics 21.0软件,测量眼眶容积及眶周骨骼间宽度,采用SPSS 20.0软件进行统计分析,扩弓前后测量数据采用配对样本t检验,P0.05)。结论MSE对成年女性眼眶容积有轻微的扩大效应,可增大眶周骨骼横向宽度。

关键词：上颌骨性扩弓器上颌骨宽度不足成年女性眼眶容积

支持终端晃动的多光源可见光通信系统有效容量研究

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电子与信息学报 2022年第8期44卷 2717-2724页

作者：钱磊刘飞扬赵琳琳戈立军迟学芬天津工业大学电子与信息工程学院天津300387 天津市光电检测技术与系统重点实验室天津300387 吉林大学通信工程学院长春130012 伦敦大学学院计算机科学学院伦敦WC1E 6BT

作为下一代网络的重点候选技术,可见光通信(VLC)以其超高的传输速率有望提供严格的时延服务质量(QoS)保障。现有VLC研究大多假设终端在接收信号过程中始终保持垂直向上。然而,在实际VLC系统中,终端晃动将对接收端入射角产生较大的影响,... 详细信息

作为下一代网络的重点候选技术,可见光通信(VLC)以其超高的传输速率有望提供严格的时延服务质量(QoS)保障。现有VLC研究大多假设终端在接收信号过程中始终保持垂直向上。然而,在实际VLC系统中,终端晃动将对接收端入射角产生较大的影响,从而对VLC的信道增益与传输速率产生影响。该文针对统计时延QoS约束下多光源VLC系统晃动终端的可达传输速率展开研究。首先,基于3维离散时间马尔可夫链,提出VLC终端3自由度晃动模型,从时间相关性的角度刻画了VLC终端的随机晃动过程;其次,将终端晃动下多光源VLC系统的矢量传输过程映射为马尔可夫式服务过程,基于有效容量理论,研究支持终端晃动的VLC系统在统计时延QoS约束下的可达传输速率;最后,通过仿真实验说明了终端晃动对VLC系统容量的影响并验证了所推导有效容量的准确性。

关键词：可见光通信终端晃动时延QoS 有效容量

Ultrathin two-dimensional hybrid perovskites toward flexible electronics and optoelectronics

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National Science Review 2022年第5期9卷 10-12页

作者： Junran Zhang xuefen Song Lin Wang Wei Huang Key Laboratory of Flexible Electronics and Institute of Advanced Materials School of Physical and Mathematical Sciences Nanjing Tech University Frontiers Science Center for Flexible Electronics Key Laboratory of Flexible ElectronicsShaanxi Institute of Flexible Electronics Institute of Flexible Electronics Northwestern Polytechnical University

The past decade has witnessed an explosion of research into organic-inorganic hybrid perovskites (OIHPs) due to their outstanding properties,including high flexibility,high absorption/emission efficiency,large defect tolerance and long-distance carrier diffusion [1].Recently,the ultrathin two-dimensional(2D) OIHP (Fig.1),combining the attractive features of hybrid components and 2D morphology,can be considered a rising star among novel flexible materials.

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超顺磁性还原氧化石墨烯/Fe_3O_4空心球纳米复合材料的合成、表征及性能研究（英文）

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稀有金属材料与工程 2016年第7期45卷 1669-1673页

作者：董浩迟学芬曲良东赵晓晖吉林大学吉林长春130012

采用一种简单有效的静电自组装的方法成功合成出还原氧化石墨烯包覆Fe_3O_4空心球纳米复合材料(r-GO/Fe_3O_4)。运用X射线粉末衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、高分辨透射电镜(HRTEM)、红外-可见光谱(FT-IR)以及... 详细信息

采用一种简单有效的静电自组装的方法成功合成出还原氧化石墨烯包覆Fe_3O_4空心球纳米复合材料(r-GO/Fe_3O_4)。运用X射线粉末衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、高分辨透射电镜(HRTEM)、红外-可见光谱(FT-IR)以及拉曼光谱等手段对合成出的产物进行了系统的表征。r-GO/Fe_3O_4纳米复合材料表现出优良的超顺磁性,室温下的饱和磁化强度高达70.2A·m^2·kg^(-1),并且在外加磁场下可以快速在水溶液中实现分散和分离。较高的饱和磁化强度和优良的水分散性使得这种新型的r-GO/Fe_3O_4纳米复合材料在包括磁共振成像、生物传感器、通信以及微波吸收等领域具有一定的应用价值。

关键词： Fe_3O_4 石墨烯纳米复合材料超顺磁性

Coordination of thin-film nanofibrous composite dialysis membrane and reduced graphene oxide aerogel adsorbents for elimination of indoxyl sulfate

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chinese Journal of Chemical Engineering 2022年第9期35卷 111-121页

作者： Yuanyuan Jin Siping Ding Peiyun Li xuefen Wang State Key Lab for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China

The protein-bound uremic toxins,represented by indoxyl sulfate(IS),have been associated with the progression of chronic kidney disease and the development of cardiovascular disease in the presence of impaired renal function.Herein,we proposed a novel strategy of thin-film nanofibrous composite(TNFC)dialysis membrane combined with reduced graphene oxide(rGO)aerogel adsorbents for clinical removal of IS as well as high retention of proteins.The TFNC membrane was prepared by electrospinning in conjunction with coating-reaction method and proved to have good selectivity and permeability.To further improve the removal rate of toxins,we used a medium hydrothermal method following by freeze-drying treatment to obtain the r GO aerogel adsorbents.It exhibited excellent adsorption for IS with a maximum adsorption capacity of 69.40 mg·g^(-1)throughπ-πinteraction and hydrogen bonding interaction based on Langmuir isotherm models.Time-dependent absorption experiments showed that it reached adsorption equilibrium within 4 h,which was matched with the hemodialysis time.The coordination was significantly exhibited by introducing r GO aerogel blocks into the dialysate for absorbing the diffused free IS during hemodialysis.Taking the advantages of the TFNC dialysis membrane and the rGO aerogel,the volume of dialysate for hemodialysis was only one-tenth of that without adsorbent blocks but with very comparable dialysis performance(the clearance of IS at 51.8%and the retention of HSA over 98%),which could lighten conventional hemodialysis effectively and be benefit to realize the miniaturization of the hemodialysis equipment.Therefore,the coordination of the TFNC dialysis membrane and rGO aerogel adsorbents would open a new path for the development of portable artificial kidney.

关键词： Indoxyl sulfate Thin-film nanofibrous composite membrane rGO aerogel adsorbents Hemodialysis Coordination Portable artificial kidney