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Optoelectronics Letters 2024年

作者： JIA Xishan li jining YAO Yuan WANG Yifan liU Bo XU Degang School of Precision Instruments and Opto-electronics Engineering， Tianjin University Key Laboratory of Optoelectronics Information Technology (Ministry of Education)， Tianjin University Institute of Modern Optics， College of Electronic Information and Optical Engineering， Nankai University Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology

In this paper， an improved error-rate sliding window decoder is proposed for spatially coupled low-density parity-check (SC-LDPC) codes. For the conventional sliding window decoder， the message retention mechanism causes unreliable messages along the edges of belief propagation (BP) decoding in the current window to be kept for subsequent window decoding. To improve the reliability of the retained messages during the window transition， a reliable termination method is embedded， where the retained messages undergo more reliable parity checks. Additionally， decoding failure is unavoidable and even causes error propagation when the number of errors exceeds the error-correcting capability of the window. To mitigate this problem， a channel value reuse mechanism is designed， where the received channel values are utilized to reinitialize the window. Furthermore， considering the complexity and performance of decoding， a feasible sliding optimized-window decoding (SOWD) scheme is introduced. Finally， simulation results confirm the superior performance of the proposed SOWD scheme in both the waterfall and error floor regions. This work has great potential in the applications of wireless optical communication and fiber optic communication.

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人工智能技术在电气自动化控制中的应用

模具制造 2024年第10期24卷 27-29页

作者：胡菁华李冀宁中冶北方(大连)工程技术有限公司辽宁大连116000

电气工程自动化智能控制作为新型工程科学较有代表性的一员,基于生产活动中工作可靠、高质量进行的要求,以人工智能对生产期间的工作进行分析与控制。智能控制技术已经获得较多研究成果,在具体场域中得到广泛运用,可实现工作的合理操控... 详细信息

电气工程自动化智能控制作为新型工程科学较有代表性的一员,基于生产活动中工作可靠、高质量进行的要求,以人工智能对生产期间的工作进行分析与控制。智能控制技术已经获得较多研究成果,在具体场域中得到广泛运用,可实现工作的合理操控,让活动高效进行。传统电气工程控制设备在生产期间的运用,能够减少人类在生产活动中的投入量,变相降低生产投资总额,提高生产工作的利润。围绕电气自动化控制中人工智能的运用进行论述,希望研究内容对人工智能在电气自动化控制中的运用价值提升带来积极作用。

关键词：电气自动化控制人工智能技术数据整合

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kHz、mJ量级的可调谐MgO∶PPLN中红外光参量振荡器

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中国激光 2024年第7期51卷 227-233页

作者：刘帅陈锴孙悦闫超乔鸿展常继英李吉宁王与烨钟凯徐德刚姚建铨天津大学精密仪器与光电子工程学院天津300072 天津大学光电信息技术教育部重点实验室天津300072 天津大学微光机电系统技术教育部重点实验室天津300072

3~5μm中红外波段激光在大气中具有较高的透过率,因此被广泛应用于光电对抗等领域。报道了基于掺杂氧化镁的周期极化铌酸锂(MgO∶PPLN)晶体的kHz、mJ量级的中红外光学参量振荡器(OPO)。采用纳秒脉冲1064 nm激光泵浦基于多周期MgO∶PPLN... 详细信息

3~5μm中红外波段激光在大气中具有较高的透过率,因此被广泛应用于光电对抗等领域。报道了基于掺杂氧化镁的周期极化铌酸锂(MgO∶PPLN)晶体的kHz、mJ量级的中红外光学参量振荡器(OPO)。采用纳秒脉冲1064 nm激光泵浦基于多周期MgO∶PPLN晶体的OPO,OPO采用泵浦双通单谐振平凹腔结构。中红外激光的重复频率为1 kHz,4.08μm处输出的最高单脉冲能量达到1.041 mJ。最高光-光转换效率为16.8%,斜效率为19.3%,中红外激光脉宽约为9.53 ns。在最高能量输出时,OPO运转30 min时输出功率的均方根(RMS)为0.24%。通过温度-极化周期结合的调谐方式,OPO在3.49~4.18μm的较宽范围内都能够保持0.9 W以上平坦的高能量输出。在极化周期27.5~29.6μm以及温度25~200℃的调节范围内,闲频光波长的调谐范围为3.49~4.48μm。实现了重复频率为kHz量级、单脉冲能量为mJ量级的可调谐中红外输出,其在光电对抗领域具有应用价值。

关键词：激光器中红外激光掺杂氧化镁的周期极化铌酸锂全固态激光器光参量振荡器

Microstructure and properties of Al_2O_3-13%TiO_2 coatings sprayed using nanostructured powders

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Rare Metals 2007年第4期26卷 391-397页

作者： ZHANG Jianxin HE jining DONG Yanchun li Xiangzhi YAN Dianran School of Materials Science and Engineering Hebei University of Technology Tianjin 300130 China

The microstructure and wear performance of M203-13% TiO2 coatings prepared by plasma spraying of agglom- erated nanoparticle powders were investigated. SEM analysis showed that the as-sprayed Al2O3-TiO2 coatings comprise of two kinds of typical region： fully melted region and unmelted/partially melted nanostructured region, which is different than the conventional coating with lamellar structure. It is shown that the microhardness of the nanostructured coatings was about 15%-30% higher than that of the conventional coating and the wear resistance is significantly improved, especially under a high wear load. The nanostructured coating sprayed at a lower power shows a lower wear resistance than the coatings produced at a higher power, because of the presence of pores and microstructural defects which are detrimental to the fracture toughness of the coatings.

关键词： surface coating nanostructured coating plasma spray microhardness wear resistance

Post-evaluation of a water pollution control plan： methodology and case study

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Frontiers of Environmental Science & Engineering 2015年第4期9卷 712-724页

作者： lin ZENG Xin DONG Siyu ZENG Tianzhu ZHANG Jing li jining CHEN School of Environment Tsinghua University Beijing 100084 China

China has developed more than 20 water pollution control plans for river basins （RBWPs） since 1996. However, the implementation has generally lagged. This paper proposes a three-step, post-evaluation methodology to analyze the implementation result of a RBWP and its influential factors. First, a multi-attribute evaluation method based on an index system is established to score the enforcement results of a RBWP. Indicators measure how well a RBWP has achieved its objectives, which include water quality compliance, pollution load control, project construction, financial inputs, and related management requirements. Second, an interpretive structural model is used to detect the significant factors that affect RBWP implementation. This model can effectively analyze the cause-effect chain and hierarchical relationship among variables. Five groups of factors were identified, namely, plan preparation, water resource endowment, policy, institution, and management. Both qualitative and quantitative methods are employed in the third step to evaluate the extent to which these factors have influenced the execution result of a RBWP, including pre-post contrast, scenario analysis, and correlation analysis. This research then post-evaluated the implementation of the Huai River Basin water pollution control plans （H-RBWPs） over a period of 10 years as a case study. Results showed that the implementation of the H-RBWPs was unsatisfactory during 2001–2005, although it improved during 2006–2010. The poor execution of these plans was partially caused by the underestimation of regional economic development in combination with ineffective industrial structure adjustment policies. Therefore, this case study demonstrates the feasibility and flexibility of the proposed post-evaluation methodology.

关键词： river basin water pollution control plan postplan evaluation multi-attribute comprehensive evaluation,interpretive structural model combined qualitative/quantitative method

Trade-off evaluation using carbon dioxide equivalent and hazard index of a paddy soil with application of organic liquid fertilizer

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Pedosphere 2022年第6期32卷 928-932页

作者： Shohei RIYA Ryo IMANO jining li Huifeng SUN Sheng ZHOU Masaaki HOSOMI Department of Chemical Engineering Faculty of EngineeringTokyo University of Agriculture and Technology2-24-16 Naka-ChoKoganeiTokyo 184-8588(Japan) School of Environment Nanjing Normal UniversityNanjing 210023(China) Eco-Environmental Protection Research Institute Shanghai Academy of Agricultural SciencesShanghai 201403(China)

Dear Editor,Rice is an important staple food crop in Asia,but the anaerobic soil conditions in rice fields cause emission of the potent greenhouse gas,methane(CH)(Le Mer and Roger,2001),and promote the accumulation of arsenic(As)in the grain(Le Mer and Roger,2001;Khanam et al.,2020).To facilitate sustainable agriculture,using wastewater as an organic fertilizer is essential for reducing wastewater treatment-associated energy consumption and the recycling of wastewater nutrients(Zou et al.,2009).

关键词： wastewater soil dioxide

Molecular diversity of arbuscular mycorrhizal fungi at a large-scale antimony mining area in southern China

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Journal of Environmental Sciences 2015年第3期27卷 18-26页

作者： Yuan Wei Zhipeng Chen Fengchang Wu Hong Hou jining li Yuxian Shangguan Juan Zhang Fasheng li Qingru Zeng State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Science College of Resources and Environment Hunan Agricultural University

Arbuscular mycorrhizal fungi （AMF） have great potential for assisting heavy metal hyperaccumulators in the remediation of contaminated soils. However, little information is available about the community composition of AMF under natural conditions in soils contaminated by antimony （Sb）. The objective of this study was to investigate the characteristics of AMF molecular diversity, and to explore the effects of Sb content and soil properties on the AMF community structure in an Sb mining area. Four Sb mine spoils and one adjacent reference area were selected from around the Xikuangshan mine in southern China. The association of AMF molecular diversity and community composition with the rhizosphere soils of the dominant plant species was studied by Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis （PCR-DGGE）. Results from all five studied sites showed that the diversity of AMF decreased with increasing Sb concentration. Principal component analysis （PC_A） indicated that the AMF community structure was markedly different among these groups. Further redundancy analysis （RDA） showed that Sb contamination was the dominating factor influencing the AMF community structure in the Sb mine area. However, the multivariate analysis showed that, apart from the soil Sb content, extractable nitrogen content and organic matter content also attributed to AMF sequence distribution type. Some AMF sequences were only found in the highly contaminated area and these might be ideal candidates for improving phytoremediation efficiency in Sb mining regions. Gene sequencing analysis revealed that most species were affiliated with Gloraus, suggesting that Glomus was the dominant AMF genus in the studied Sb mining area.

关键词： Antimony Arbuscular mycorrhizal fungi Molecular diversity Gommunity structure

“互联网+”背景下“园艺综合实验”课程的教学改革探索

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计算机应用文摘 2024年第7期40卷 32-33,37页

作者：李金英高悦王颖吴林刘海广吉林农业大学园艺学院长春130118

随着互联网时代的快速发展,我国的教育教学方式经历了翻天覆地的变革。作为在课本知识基础上进行的实践能力拓展,园艺实践教学对当代农业学生来说至关重要。文章以吉林农业大学园艺专业为例,对“园艺综合实验”课程在教学过程中存在的... 详细信息

随着互联网时代的快速发展,我国的教育教学方式经历了翻天覆地的变革。作为在课本知识基础上进行的实践能力拓展,园艺实践教学对当代农业学生来说至关重要。文章以吉林农业大学园艺专业为例,对“园艺综合实验”课程在教学过程中存在的问题进行了简要分析,并提出了相应的改革措施。

关键词：园艺专业综合实验教学互联网+ 课程改革

Study on Environment Perception and Automatic Navigation Technology for the Automatic Parking System

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World Journal of Engineering and Technology 2015年第3期3卷 46-51页

作者： Yibing Zhao jining li Yuan Yang Department of Vehicle Engineering State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian China The Digital Arts Department Dalian Neusoft Institute of Information Dalian China

The traffic accidents, traffic jams and parking problems come to appear, and have caused more and more concerns of people. The automatic parking system can help us a lot to solve these problems. The automatic parking system in this paper includes two sections, environment perception and automatic controller. The median filter and least square method are used to process the laser sensor data. Then, feasible parking space can be displayed by using K-means clustering method. The Matlab fuzzy GUI is used to establish the fuzzy controller. The kinematics equation of car is utilized to simulate the automatic vertical parking in the Matlab/simulation with the different initial path angles. Experiment results show that the environmental perception method has perfect performance and the controlling algorithm of the automatic parking system has good feasibility.

关键词： Environment Perception Automatic Navigation Automatic Parking System

Optical rectification in 4H-SiC:paving the way to generate strong terahertz fields with ultra-wide bandwidth

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High Power Laser Science and Engineering 2023年第5期11卷 115-126页

作者： Fangjie li Kai Zhong Yiwen Zhang Tong Wu Yuxin liu Hongzhan Qiao jining li Degang Xu Jianquan Yao School of Precision Instruments and Optoelectronics Engineering Tianjin UniversityTianjinChina Key Laboratory of Opto-electronic Information Technology Ministry of Education(Tianjin University)TianjinChina School of Marine Science and Technology Tianjin UniversityTianjinChina

The 4H-SiC crystal is found to have great potential in terahertz generation via nonlinear optical frequency conversion due to its extremely high optical damage threshold,wide transparent range,*** this paper,optical rectification(OR)with tilted-pulse-front(TPF)setting based on the 4H-SiC crystal is *** theory accounts for the optimization of incident pulse pre-chirping in the TPF OR process under high-intensity femtosecond laser *** with the currently recognized liNbO3-based TPF OR,which generates a single-cycle terahertz pulse within 3 THz,4HSiC demonstrates a significant advantage in producing ultra-widely tunable(up to over 14 THz,TPF angle 31◦–38◦)terahertz waves with high efficiency(~10–2)and strong field(~MV/cm).Besides,the spectrum characteristics,as well as the evolution from single-to multi-cycle terahertz pulses can be modulated flexibly by *** simulation results show that 4H-SiC enables terahertz frequency extending to an unprecedent range by OR,which has extremely important potential in strong-field terahertz applications.

关键词： optical rectification silicon carbide terahertz radiation tilted-pulse-front