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Hierarchical mobility prediction in the future heterogeneous networks for the tradeoff between accuracy and complexity

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The Journal of China Universities of Posts and Telecommunications 2019年第3期26卷 15-24页

作者： liu Zhenya Li Xi Ji Hong Zhang heli Key Laboratory of Universal Wireless Communications Beijing University of Posts and Telecommunications Beijing 100876 China School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

Mobility prediction is one of the promising technologies for improving quality of service(QoS) and network resource utilization. In future heterogeneous networks(HetNets), the network topology will become extremely complicated due to the widespread deployment of different types of small-cell base stations(SBSs). For this complex network topology, traditional mobility prediction methods may cost unacceptable overhead to maintain high prediction accuracy. This problem is studied in this paper, and the hierarchical mobility prediction scheme(HMPS) is proposed for the future HetNets. By dividing the entire process into two prediction stages with different granularity, the tradeoff between prediction accuracy and computational complexity is investigated. Before performing prediction of user mobility, some frequently visited locations are identified from the user’s trajectory, and each location represents an important geographic area(IGA). In the coarse-grained prediction phase, the next most possible location to be visited is predicted at the level of the possible geographic areas by using a second-order Markov chain with fallback. Then, the fine-grained prediction of user position is performed based on hidden Markov model(HMM) from temporal and spacial dimensions. Simulation results demonstrate that, compared with the existing prediction methods, the proposed HMPS can achieve a good compromise between prediction accuracy and complexity.

关键词： mobility prediction heterogeneous networks prediction accuracy and complexity Markov chain, HMM

大鼠异位心脏移植对心脏减负荷模型制作的价值

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新医学 2022年第3期53卷 193-198页

作者：刘永辉孟嘉天孟自力蔡会卿刘何利周香坦河北省胸科医院石家庄050041 河北省安国市中医院安国071200 河北省沧州中西医结合医院沧州061000 河北省河间市人民医院沧州062450

目的探讨大鼠心脏减负荷模型的制作要点,为心力衰竭患者使用左心室辅助装置恢复机制提供实用模型。方法同系29只Lewis成年大鼠,通过结扎冠状动脉前降支形成缺血性心肌病,用UCG筛选符合心力衰竭条件的大鼠。将24只心力衰竭大鼠随机分为2... 详细信息

目的探讨大鼠心脏减负荷模型的制作要点,为心力衰竭患者使用左心室辅助装置恢复机制提供实用模型。方法同系29只Lewis成年大鼠,通过结扎冠状动脉前降支形成缺血性心肌病,用UCG筛选符合心力衰竭条件的大鼠。将24只心力衰竭大鼠随机分为2组:减负荷组(n=14)与心衰组(n=10)。心衰组不进行心脏移植。减负荷组对心力衰竭大鼠心脏作为供体异位移植于受体腹部下腔静脉及腹主动脉,形成左心室减负荷模型。另设空白对照组(n=8),这些大鼠仅仅接受开胸手术,而不实施冠状动脉前降支的结扎,其它处理方式同以上2组。实施心脏移植2周后,分别对3组小鼠进行检测。检测指标包括测量左室舒张末压、最大压力上升速率(+dp/dt_(max))及左室收缩压,并作心脏病理切片检测组织学改变。结果缺血性心肌病心力衰竭动物模型成功率为82.76%(24/29),心力衰竭大鼠进行心脏减负荷后的存活率是71.43%(10/14)。与心衰组相比,减负荷组左心室发展压升高(47.85±0.94 vs.35.94±0.95,F=250.993,P<0.05),左心室+dp/dt_(max)升高(1177.85±61.03 vs.841.64±40.26,F=942.304,P<0.05)。结论利用大鼠作为实验动物,通过先制作心肌梗死心力衰竭模型,再对其进行异位心脏移植,可作为经济、可重复的心室减负荷模型。

关键词：动物模型,大鼠左心室辅助装置减负荷心脏移植

维普期刊数据库博看期刊

More than Carbon Stocks:A Case Study of Ecosystem-based Benefits of REDD+ in Indonesia

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Chinese Geographical Science 2012年第4期22卷 390-401页

作者： LU heli YAN Weiyang QINYaochen liu Guifang Institute of Natural Resources and Environmental Science Henan University Kaifeng 475004 China Key Laboratory of Geospatial Technology for Middle and Lower Yellow River Regions of Ministry of Education Henan University Kaifeng 475004 China)

During the 15th Conference of the Parties （COP 15）, Parties agreed that reducing emissions from deforesta- tion and forest degradation and enhancing ＇removals of greenhouse gas emission by forests＇（REDD＋） in developing countries through positive incentives under the United Nations Framework Convention on Climate Change （UNFCCC） was capable of dealing with global emissions. As REDD＋ seeks to lower emissions by stopping deforestation and for- est degradation with an international payment tier according to baseline scenarios, opportunities for ecosystem benefits such as slowing habitat fragmentation, conservation of forest biodiversity, soil conservation may be also part of this effort. The primary objective of this study is to evaluate ecosystem-based benefits of REDD＋, and to identify the rela- tionships with carbon stock changes. To achieve this goal, high resolution satellite images are combined with Normal- ized Difference Vegetation Index （NDVI） to identify historical deforestation in study area of Central Kalimantan, In- donesia. The carbon emissions for the period of 2000-2005 and 2005-2009 are 2.73 ×10^5 t CO2 and 1.47× 10^6 t CO2 respectively, showing an increasing trend in recent years. Dring 2005-2009, number of patches （NP）, patch density （PD）, mean shape index distribution （SHAPE_MN） increased 30.8%, 30.7% and 7.6%. Meanwhile, largest patch index （LPI）, mean area （AREA MN）, area-weighted mean of shape index distribution （SHAPE_AM）, neighbor distance （ENN_MN） and interspersion and juxtaposition index （IJI） decreased by 55.3%, 29.7%, 15.8%, 53.4% and 21.5% re- spectively. The area regarding as positive correlation between carbon emissions and soil erosion was approximately 8.9 x l03 ha corresponding to 96.0% of the changing forest. These results support the view that there are strong syner- gies among carbon loss, forest fragmentation and soil erosion in tropical forests. Such mechanism of REDD＋ is likely to present opportunities for multiple benefits that

关键词： REDD+ carbon ecosystem-based benefits deforestation Indonesia

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苏州市近年吸毒流行病学特征分析及对策

中国药物滥用防治杂志 2005年第6期11卷 337-338页

作者：杨之江朱晓峰刘贺丽何朝根顾永康苏州市戒毒所苏州215000

目的:调查与分析近一年多来苏州市毒品吸食的流行病学特征。方法:对苏州市公安局戒毒所2004年1月―2005年3月期间,收戒治疗的1003例强制戒毒人员进行调查分析,并与我所1999年的相关资料进行了比较。结果:近期苏州市吸毒人群以16～35a的... 详细信息

目的:调查与分析近一年多来苏州市毒品吸食的流行病学特征。方法:对苏州市公安局戒毒所2004年1月―2005年3月期间,收戒治疗的1003例强制戒毒人员进行调查分析,并与我所1999年的相关资料进行了比较。结果:近期苏州市吸毒人群以16～35a的外来汉族男性青年为主,大多为无业人员,文化程度普遍较低,多在初中以下(含初中),毒品主要来源是黑市购买。结论:近年苏州地区吸毒人员以外来人员为多,比五年前有了显著上升,并就上述特征提出了相应对策。

关键词：吸毒流行病学特征流行病学对策

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锌浸渣浮选银精矿还原焙烧-低酸浸出脱锌

有色金属（冶炼部分） 2024年第7期 25-32页

作者：黄玉柱裴双刘宇倩周合理朱晓红胡宇杰湖南工业大学材料与先进制造学院湖南株洲412007

以某湿法炼锌厂产出的锌浸渣浮选银精矿为原料,采用回转炉还原焙烧—低酸浸出工艺进行脱锌研究。结果表明:在碳粉加入量10%、焙烧温度600℃、时间120 min、原料粒度-0.1 mm、回转炉转速5 r/min的条件下,铁酸锌还原焙烧分解效果最优,焙... 详细信息

以某湿法炼锌厂产出的锌浸渣浮选银精矿为原料,采用回转炉还原焙烧—低酸浸出工艺进行脱锌研究。结果表明:在碳粉加入量10%、焙烧温度600℃、时间120 min、原料粒度-0.1 mm、回转炉转速5 r/min的条件下,铁酸锌还原焙烧分解效果最优,焙烧产物中可溶锌率达到85.83%。在硫酸终点pH为2、液固比5 mL/g、浸出温度70℃、浸出时间90 min优化条件下,对焙烧产物进行选择性浸出,锌和铁的浸出率分别为84.23%和34.71%。浸出渣中未溶解铁锌氧化物主要为还原焙烧过程中团聚成块的大颗粒及被硫酸铅熔化包裹形成的颗粒。

关键词：锌浸渣浮选银精矿铁酸锌还原焙烧低酸浸出脱锌工艺

超纯铁素体不锈钢中TiN夹杂析出的热力学分析

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武汉科技大学学报 2012年第5期35卷 347-351页

作者：张帆李光强李永军刘赫莉陈兆平武汉科技大学钢铁冶金及资源利用省部共建教育部重点实验室湖北武汉430081 宝山钢铁股份有限公司研究院上海201900

为了控制TiN夹杂对材料性能的不利影响,对TiN在超纯铁素体不锈钢冶炼和凝固过程中析出的热力学条件进行分析。结果表明,在Cr含量为16%～23%的条件下,超纯铁素体不锈钢的最佳钛含量为0.1%～0.3%;当w(Ti)=0.3%时,将w(N)控制在0.004 6%以... 详细信息

为了控制TiN夹杂对材料性能的不利影响,对TiN在超纯铁素体不锈钢冶炼和凝固过程中析出的热力学条件进行分析。结果表明,在Cr含量为16%～23%的条件下,超纯铁素体不锈钢的最佳钛含量为0.1%～0.3%;当w(Ti)=0.3%时,将w(N)控制在0.004 6%以下才能避免在液相区中生成TiN夹杂;超纯铁素体不锈钢凝固过程中钛的富集程度稍低于氮;凝固末期残余液相中[Ti]和[N]的浓度分别提高到其初始浓度的2.5倍和3.2倍;随着钢液的逐渐凝固,凝固前沿温度和凝固前沿钛氮平衡浓度积下降,凝固前沿钛氮实际浓度积升高;降低钢中氮含量能推迟TiN析出时间,使TiN夹杂在凝固末期形成,可减小TiN夹杂尺寸,减少其析出数量。

关键词：超纯铁素体不锈钢 TiN夹杂析出热力学分析

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缺氧性血管内皮细胞凋亡分子机制的实验研究

包头医学院学报 2007年第4期23卷 345-347页

作者：石瑞丽刘和莉孙小荣俞惠敏张胜张建军包头医学院内蒙古包头014010 中国医学科学院药物研究所

目的:研究Caspase-3在缺氧性血管内皮细胞凋亡中的作用。方法:用NaCN合并无糖培养基造成培养的牛主动脉内皮细胞(BAECs)化学性缺氧(C I);应用台盼兰染色、TUNEL、流式细胞仪计数和Hoechst 33342荧光染色的方法观察细胞受损和凋亡情况;... 详细信息

目的:研究Caspase-3在缺氧性血管内皮细胞凋亡中的作用。方法:用NaCN合并无糖培养基造成培养的牛主动脉内皮细胞(BAECs)化学性缺氧(C I);应用台盼兰染色、TUNEL、流式细胞仪计数和Hoechst 33342荧光染色的方法观察细胞受损和凋亡情况;应用免疫细胞化学染色的方法观察内皮细胞Caspase-3的表达。结果:Caspase-3的选择性抑制剂可显著减少缺氧性血管内皮细胞凋亡的发生,在Caspase-1和Caspase-6的选择性抑制剂作用下,Caspase-3的表达明显减少。结论:提示Caspase-3参与了缺氧性血管内皮细胞凋亡的发生,在Caspases的蛋白酶级联切割反应中,Caspase-3位于Caspase-1和Caspase-6的下游。

关键词：血管内皮细胞缺氧凋亡 Caspases-1 Caspases-3 Caspases-6

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丹皮酚的抗炎作用研究

包头医学院学报 2008年第3期24卷 238-239页

作者：武海军徐继辉李月玲刘和莉杨玉梅包头医学院药理学教研室内蒙古包头014010

目的:观察二氧化碳(CO2)超临界提取的丹皮酚的抗炎作用。方法:用醋酸导致小鼠腹腔毛细血管通透性增加;用角叉菜胶导致大鼠足跖肿胀。结果:丹皮酚50.0、25.0、12.5 mg/kg灌胃给药,可明显降低小鼠腹腔毛细血管通透性;丹皮酚32.0、16.0、8.... 详细信息

目的:观察二氧化碳(CO2)超临界提取的丹皮酚的抗炎作用。方法:用醋酸导致小鼠腹腔毛细血管通透性增加;用角叉菜胶导致大鼠足跖肿胀。结果:丹皮酚50.0、25.0、12.5 mg/kg灌胃给药,可明显降低小鼠腹腔毛细血管通透性;丹皮酚32.0、16.0、8.0mg/kg灌胃给药,能显著抑制角叉菜胶所引起的大鼠足肿胀。结论:经CO2超临界提取的丹皮酚具有明显的抗炎作用。

关键词：丹皮酚二氧化碳超临界提取抗炎

Modeling the impacts of policy interventions from REDD+ in Southeast Asia: A case study in Indonesia

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Science China Earth Sciences 2014年第10期57卷 2374-2385页

作者： LU heli liu GuiFang Institute of Natural Resources and Environmental Science Henan Collaborative Innovation Center for Coordinated Developments in Central China Economic Zone Henan University United Nations University-Institute of Advanced Studies

Reducing Emissions from Deforestation and Forest Degradation(REDD+) and enhancing "removals of greenhouse gas emissions by forests" in developing countries through positive incentives is regarded as an essential component of the post-2012 climate regime for stabilizing greenhouse gas emissions and an important way of engaging developing countries in global mitigation efforts. We aimed to evaluate the potential effectiveness of REDD+ by integrating it into a land use option framework. One of our goals was to develop scenarios for evaluating the impacts of land use changes on carbon and environmental processes. In addition, we aimed to quantify the potential economic benefits to society of compensated reductions and to identify hotspots for applying REDD+. Three land use change scenarios were examined:(I) business as usual(BAU),(II) economic development, and(III) REDD+. A case study in Indonesia was examined using these land use scenarios and policy interventions, evaluating their effects on carbon emissions, socioeconomics, and environmental features of a spatial system using land use models. Significant emissions and water erosion reductions were predicted to be achieved under the REDD+ scenario, due to reduced deforestation of 0.14 Mt CO2 e reduction was predicted relative to the BAU scenario. Furthermore, the spatial land use model indicated that REDD+ payments of forest carbon credits in the compliance market would play a key role in compensating rural communities and plantation companies for their opportunity cost in ending deforestation. This study provides an example of integrating land use modeling with a scenario analysis framework to evaluate plausible future forecasts and to evaluate the potential impacts of REDD+.

关键词： deforestation and forest degradation greenhouse gas emissions land use Southeast Asia policy intervention