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A Fairness Resource Allocation Algorithm for Coverage and Capacity Optimization in Wireless Self-Organized Network

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China Communications 2018年第11期15卷 10-24页

作者： Pan Zhao Lei Feng Peng yu Wenjing Li xuesong Qiu State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China Henan University of Technology Zhengzhou 450007 China

To achieve the higher resource efficiency, Coverage and Capacity Optimization(CCO) as an important role of the network self-healing and self-optimization, has become a focus topic in wireless Self-Organized Network(SON). In this paper, a novel CCO scheme is proposed to maximize utility function of the integrated coverage and capacity. It starts with the analysis on the throughput proportional fairness(PF) algorithm and then proposes the novel Coverage and Capacity Proportional Fairness(CCPF) allocation algorithm along with a proof of the algorithms convergence. This proposed algorithm is applied in a coverage capacity optimization scheme which can guarantee the reasonable network capacity by the coverage range accommodation. Next, we simulate the proposed CCO scheme based on telecom operators' real network data and compare with three typical resource allocation algorithms: round robin(RR), proportional fairness(PF) and max C/I. In comparison of the PF algorithm, the numerical results show that our algorithm increases the average throughput by 1.54 and 1.96 times with constructed theoretical data and derived real network data respectively.

关键词： self-organized network coverageand capacity optimization resource allocationalgorithm user fairness.

Evaluation of the secondary structures of protein in the extracellular polymeric substances extracted from activated sludge by different methods

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Journal of Environmental Sciences 2019年第6期31卷 128-136页

作者： Benyi Xiao yu Liu Meng Luo Tang Yang xuesong Guo Hao Yi Research Center for Eco-Environmental Sciences Chinese Academy of Sciences University of Chinese Academy of Sciences Beijing ZEHO Waterfront Ecological Environment Treatment Company South China Institute of Environmental Sciences Ministry of Environmental Protection

The changes of protein secondary structures in the extracellular polymeric substances(EPS) extracted from activated sludge by four different methods were studied by analyzing the amide I region(1700–1600 cm-1) of the Fourier transform infrared spectra and model protein test. The results showed the molecular weight distribution of organic matter extracted by centrifugation, heating and cation exchange resin(CER) was similar, while the EPS extracted by centrifugation(Control) and CER had similar fluorescent organic matter. The protein secondary structures of extracted EPS by the four methods were different. The similarities of protein secondary structures between the EPS extracted by CER with the Control were the highest among the four extracted EPS. Although the EPS yield extracted by formaldehyde + NaOH method were the highest, its protein secondary structures had the lowest similarity with those extracted by the Control. Additionally, the effects of centrifugation and CER extraction on the secondary structures of bovine serum albumin were also lower than that of other extraction processes. CER enables the second maximum extraction of EPS and maximum retention of the original secondary structure of proteins.

关键词： Activated sludge Different extraction methods Extracellular polymeric substances Protein secondary structure

regeneration of thermally deactivated commercial V-W-Ti catalysts

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Frontiers of Chemical Science and Engineering 2012年第1期6卷 38-46页

作者： xuesong SHANG Jianrong LI Xiaowei yu Jinsheng CHEN Chi HE Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China College of Chemical Engineering Huaqiao UniversityXiamen 361021China

An effective method for the regeneration of thermally deactivated commercial monolith SCR catalysts was investigated. Two types of regenerated solutions, namely NH4C1 （l mol/L） and dilute H2SO4 （0.5 tool/L）, were employed to treat the used catalyst. The effects of temperature and the regeneration process on the structural and textural properties of the catalysts were determined by X-ray diffraction, scanning electron microscopy, N2 adsorption/desorption, elemental analysis and Fourier transform infrared spectroscopy. The results suggest that the anatase phase of the used catalyst is maintained after exposure to high temperatures. Some of the catalytic activity was restored after regeneration. The catalyst regenerated by aqueous NH4C1 had a higher activity than that of the catalyst treated by dilute H2SO4. The main reason is that the NH3 generated from the decomposition of NH4C1 at high temperatures can be adsorbed onto the catalyst which promotes the reaction. The aggregated V205 were partially re-dispersed during the regeneration process, and the intrinsic oxidation of ammonia with high concentrations of O2 is a factorthat suppresses the catalytic activity.

关键词： V2O5-WO3/TiO2 catalysts thermal deactiva-tion regeneration NH4C1 dilute H2SO4 solution

Al 1060/Pure Iron Clad Materials by Vacuum Roll Bonding and Their Solderability

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Journal of Materials Science & Technology 2013年第10期29卷 948-954页

作者： Qian Wang xuesong Leng Jiuchun Yan Weibing Guo yu Fu Tianming Luan State Key Laboratory of Advanced Welding and Joining School of Materials Science and EngineeringHarbin Institute of Technology

Al 1060/pure iron clad materials were produced by vacuum roll bonding. The effects of preheating temperature, vacuum roll reduction and initial thickness of the A11060 sheet on the metal interface and bonding strength were investigated. The interfacial microstructure was investigated and the mechanical properties of the joint were evaluated by shear testing. The bonding strength of the clad materials was generally enhanced by increasing the total reduction or preheating temperature, which caused the metal interface to flatten. No obvious reaction or diffusion layer was observed at the interface between Al 1060 and pure iron. The bonding strength increased with decreasing the initial thickness of the Al 1060 sheets. The Al 1060/pure iron clad materials were soldered with Zn-Al alloy by using an ultrasonic-assisted method. Strong bonding of the Al 1060 layer and Al 7N01 was realized without obvious Al 1060 dissolution or effect on the initial interface of Al 1060/pure iron clad materials by soldering at relatively low temperature.

关键词： Al 1060/pure iron clad materials Vacuum roll bonding Bonding strength Ultrasonic-assisted soldering

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基于改进高斯混合模型的变电站负荷聚类算法

全球能源互联网 2024年第5期7卷 591-601页

作者：余浩高镱滈潘险险徐衍会李雪松孙宇航广东电网有限责任公司电网规划研究中心广东省广州市510030 华北电力大学电气与电子工程学院北京市昌平区102206

针对传统高斯混合模型(Gaussian mixture model,GMM)聚类算法中计算复杂、收敛速度慢和人为确定聚类数目时存在盲目性和主观性等不足,提出了一种基于改进GMM的变电站负荷聚类算法。以传统GMM聚类算法为基础,采用k均值(k-means)算法确定... 详细信息

针对传统高斯混合模型(Gaussian mixture model,GMM)聚类算法中计算复杂、收敛速度慢和人为确定聚类数目时存在盲目性和主观性等不足,提出了一种基于改进GMM的变电站负荷聚类算法。以传统GMM聚类算法为基础,采用k均值(k-means)算法确定初始聚类中心。减少了GMM聚类算法迭代步骤,提高了输出结果的稳定性。输出不同聚类数下聚类结果的Davies-Bouldin(DB)指标、CalinskiHarabasz(CH)指标和轮廓系数(silhouette coefficient,SC),应用熵权法确定不同评价指标所占权重,构建聚类评价混合指数(cluster evaluation mixed index,CEM)。将聚类评价混合指数最大值对应的聚类个数作为最佳聚类数目,再次输入到改进GMM聚类算法中,得到变电站负荷聚类结果和聚类中心。结果表明,所提方法增强了传统GMM聚类算法的计算速度和稳定性,对变电站负荷具有良好的聚类综合能力,有助于实现聚类结果最优化。

关键词：高斯混合模型聚类负荷分类聚类算法聚类评价

Formation of overpressure system and its relationship with the distribution of large gas fields in typical foreland basins in central and western China

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Petroleum Exploration and Development 2021年第3期48卷 625-640页

作者： LI Wei CHEN Zhuxin HUANG Pinghui yu Zhichao MIN Lei LU xuesong PetroChina Research Institute of Petroleum Exploration&Development Beijing 100083China PetroChina Southwest Oil&Gas Field Company Chengdu 610051China PetroChina Tarim Oilfield Company Korla 841000China

Based on the data of measured formation pressure, drilling fluid density of key exploration wells and calculated pressure by well logging, combined with the analysis of natural gas geological conditions, the characteristics and formation mechanisms of formation fluid overpressure systems in different foreland basins and the relationship between overpressure systems and large-scale gas accumulation are discussed.(1) The formation mechanisms of formation overpressure in different foreland basins are different. The formation mechanism of overpressure in the Kuqa foreland basin is mainly the overpressure sealing of plastic salt gypsum layer and hydrocarbon generation pressurization in deep–ultra-deep layers, that in the southern Junggar foreland basin is mainly hydrocarbon generation pressurization and under-compaction sealing, and that in the western Sichuan foreland basin is mainly hydrocarbon generation pressurization and paleo-fluid overpressure residual.(2) There are three common characteristics in foreland basins, i.e. superimposed development of multi-type overpressure and multi-layer overpressure, strong–extremely strong overpressure developed in a closed foreland thrust belt, and strong–extremely strong overpressure developed in a deep foreland uplift area.(3) There are four regional overpressure sealing and storage mechanisms, which play an important role in controlling large gas fields, such as the overpressure of plastic salt gypsum layer, the overpressure formed by hydrocarbon generation pressurization, the residual overpressure after Himalayan uplift and denudation, and the under-compaction overpressure.(4) Regional overpressure is an important guarantee for forming large gas fields, the sufficient gas source, large-scale reservoir and trap development in overpressure system are the basic conditions for forming large gas fields, and the overpressure system is conducive to forming deep to ultra-deep large gas fields.

关键词： central and western China foreland basin overpressure system large gas field hydrocarbon generation pressurization under-compaction salt gypsum layer overpressure sealing overpressure residual

Machining fixture for adaptive CNC machining process of near-net-shaped jet engine blade

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Chinese Journal of Aeronautics 2020年第4期33卷 1311-1328页

作者： Dongbo WU Hui WANG Jinsong PENG Kaiyao ZHANG Jie yu xuesong ZHENG yunhai CHEN State Key Laboratory of Tribology Beijing Key Lab of Precision/Ultra-Precision Manufacturing Equipment and ControlDepartment of Mechanical EngineeringTsinghua UniversityBeijing 100084China Yantai University Yantai 264005China AECC Xi’an Aero-engine LTD Xi'an 710021China BEIJING POLYTECHNIC Beijing 100176China

Low stiffness and positioning problems are difficulties and challenges in the precise machining of near-net-shaped *** paper aims to achieve high accuracy in manufacturing by fixture-and deformation-control in the adaptive CNC machining *** CNC machining technology is first analyzed,and new fixture-evaluation criteria and methods to evaluate the adaptive CNC machining process fixture design are ***,a machining fixture is designed and manufactured after analyzing its positioning scheme,clamping scheme,materials(PEEK-GF30),and structure ***,the designed fixture is analyzed by FEA and experimentally verified by a cutting *** results show that the deformation of the blade is an overall rigid-body displacement,the main deformation of the blade-fixture system occurs on the four clamping heads,and this fixture can effectively protect the blade from local *** proposed clamping-sequence method reliably and effectively controls the local maximum deformation of the *** system stiffness is increased by 20 Hz,with each clamping force increased by 200 *** high-and low-frequency displacement in roughing milling or finishing milling are acceptable relative to the accuracy demand of blade *** fixture and an adaptive CNC machining process can achieve high accuracy in blade manufacturing.

关键词： Adaptive CNC machining process Clamping force Clamping sequence Fixture displacement response Machining fixture Near-net-shaped blade

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象拔蚌多肽提取物的抗氧化活性研究

广东药科大学学报 2018年第2期34卷 173-178页

作者：李振桦余雪松曹萧萧亓兵程鹏黄泽波广东药科大学生命科学与生物制药学院广东广州510006 广东药科大学生物资源与创新药物研究中心广东广州510006

目的研究海洋贝类象拔蚌多肽提取物(Panopea generosa protein hydrolyzate;Pg PH)的抗氧化作用。方法通过1,1-二苯基-2-三硝基苯肼(DPPH)自由基清除实验检测Pg PH的体外抗氧化活性,利用Hep G2细胞氧化应激模型验证Pg PH的抗氧化活性并... 详细信息

目的研究海洋贝类象拔蚌多肽提取物(Panopea generosa protein hydrolyzate;Pg PH)的抗氧化作用。方法通过1,1-二苯基-2-三硝基苯肼(DPPH)自由基清除实验检测Pg PH的体外抗氧化活性,利用Hep G2细胞氧化应激模型验证Pg PH的抗氧化活性并检测对细胞抗氧化酶活力的影响,利用模式动物秀丽线虫氧化应激模型探讨Pg PH的体内抗氧化活性。结果 Pg PH对DPPH自由基具有较好的清除能力,在质量浓度为1.0 mg/m L时DPPH清除率近60%,当浓度高于4.0 mg/m L时清除率达到90%。Pg PH能缓解H2O2对Hep G2细胞的氧化损伤,同时提高细胞超氧化物歧化酶、过氧化氢酶等抗氧化酶活力。Pg PH还能显著提高在百草枯氧化损伤下秀丽线虫的存活率。结论 Pg PH不仅具有缓解细胞氧化性损伤的潜力,还具有提高秀丽线虫在百草枯氧化胁迫条件下存活率的能力。这些结果为象拔蚌相关产品的开发提供了实验基础。

关键词：象拔蚌多肽提取物 HepG2细胞秀丽线虫抗氧化

近红外光谱及成像检测影响因素与校正方法研究进展

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激光与光电子学进展 2024年第4期61卷 29-38页

作者：周禹张睿加袁伟东蒋雪松周宏平孙梦梦张聪姜洪喆南京林业大学机械电子工程学院江苏南京210037

近红外光谱及成像检测凭借其高效、无损、非接触等优点近年来被广泛应用于农林产品、食品检测等方面。该技术可快速获取样品光谱和图像信息,进而结合化学计量学、机器学习建模等对样品进行品质安全、掺杂掺假、理化指标和产地溯源等方... 详细信息

近红外光谱及成像检测凭借其高效、无损、非接触等优点近年来被广泛应用于农林产品、食品检测等方面。该技术可快速获取样品光谱和图像信息,进而结合化学计量学、机器学习建模等对样品进行品质安全、掺杂掺假、理化指标和产地溯源等方面检测,深受各行各业的认可。但光学仪器使用环境以及被测样品性质具有局限性,光学检测结果易受到各种因素干扰,从而影响检测精度,应当予以消除或削弱。简述了近红外光谱和高光谱成像的检测基本原理,并对国内外近红外光谱及成像技术在检测时受到的影响因素进行总结与归纳,结合国内外研究学者在相关方面的研究内容,重点在温度、光照、水分、曲率变化和湿度等5个方面及相关校正方法的应用进行阐述,对当前存在的部分问题提出总结与建议,以期为相关方向的研究人员提供参考及借鉴。

关键词：近红外光谱高光谱成像无损检测化学计量学影响因素校正方法