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Temporal Characteristics of the Queueing Process ot 3uffer-aided Wireless Communications

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China Communications 2014年第A1期11卷 48-55页

作者： DONG Yunquan FAN Pingyi li Enyu SONG Chuanwang li yansheng SchoolofCommunicationandElectronicEngineering QingdaoTechnologicalUniversityQingdao266520China TsinghuaNationalLaboratoryforInformationScienceandTechnology andDepartmentofElectronicEngineeringTsinghuaUniversityBeijing100084China

Due to the fading property of wireless channels, the instant transmission capability of a fading channel, i.e., the instantaneous channel capacity, will change randomly along time. Usually, a finite size buffer is needed at the transmitter to match instant channel capacity with the source data stream. This paper is focused on the queuing process in the buffer. The temporal characteristics of the queueing process in the buffer are investigated, for a buffer-aided communication over block Rayleigh fading channel, in the low signal- to-noise ratio regime. Particularly, the average absorbing time for the buffer to transfer from empty state to overflow sate and from overflow state to empty state, as well as the stable working time in which neither buffer empty nor buffer overflow happens are derived. Theoretical and numerical results show that increasing the buffer size and traffic load properly will improve the efficiency of the transmission.

关键词： buffer-aided communication block Rayleigh fading absorbing time.

CH_4-CO_2 reforming to syngas over Pt-CeO_2-ZrO_2/MgO catalysts: Modification of support using ion exchange resin method

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Journal of Natural Gas Chemistry 2012年第1期21卷 76-82页

作者： Min Yang Haijun Guo yansheng li Qiong Dang School of Environment and Chemical Engineering Dalian Jiaotong UniversityDalian 116028LiaoningChina

Pt-CeO2-ZrO2/MgO （Pt-CZ/MgO） catalysts with 0.8 wt% Pt, 3.0 wt% CeO2 and 3.0 wt% ZrO2 were prepared by wet impregnation method. Support MgO was obtained using ion exchange resin method or using commercial MgO. XRD, BET, SEM, TEM, DTA-TG and CO2-TPD were used to characterize the catalysts. CH4-CO2 reforming to synthesis gas （syngas） was performed to test the catalytic behavior of the catalysts. The catalyst Pt-CZ/MgO-IE（D） prepared using ion exchange resin exhibits more regular structure, smaller and more unique particle sizes, and stronger basicity than the catalyst Pt-CZ/MgO prepared from commercial MgO. At 1073 K and atmospheric pressure, Pt-CZ/MgO-IE（D） catalyst has a higher activity and greater stability than Pt-CZ/MgO catalyst for CH4-CO2 reforming reaction at high gas hourly space velocity of 36000 mL/（g.h） with a stoichiometric feed of CH4 and C02. Activity measurement and characterization results demonstrate that modification of the support using ion exchange resin method can promote the surface structural property and stability, therefore enhancing the activity and stability for CH4-CO2 reforming reaction.

关键词： Pt-CeO2-ZrO2/MgO catalyst CH4-CO2 reforming support modification stability

MFVNet: a deep adaptive fusion network with multiple field-of-views for remote sensing image semantic segmentation

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Science China(Information Sciences) 2023年第4期66卷 93-106页

作者： yansheng li Wei CHEN Xin HUANG Zhi GAO Siwei li Tao HE Yongjun ZHANG School of Remote Sensing and Information Engineering Wuhan University

In recent years, the remote sensing image(RSI) semantic segmentation attracts increasing research interest due to its wide application. RSIs are difficult to be processed holistically on current GPU cards on account of their large field-of-views(FOVs). However, the prevailing practices such as downsampling and cropping will inevitably decrease the quality of semantic segmentation. To address this conflict,this paper proposes a new deep adaptive fusion network with multiple FOVs(MFVNet), which is specially designed for RSI semantic segmentation. Different from existing methods, MFVNet takes into consideration the differences among multiple FOVs. By pyramid sampling the RSI, we first obtain images on different scales with multiple FOVs. Images on the high scale with a large FOV can capture larger spatial contexts and complete object contours, while images on the low scale with a small FOV can keep the higher spatial resolution and more detailed information. Then scale-specific models are chosen to make the best predictions for all scales. Next, the output feature maps and score maps are aligned through the scale alignment module to overcome spatial misregistration among scales. Finally, the aligned score maps are fused with the help of adaptive weight maps generated by the adaptive fusion module, producing the fused prediction. The performance of MFVNet surpasses the previous state-of-the-art semantic segmentation models on three typical RSI datasets, demonstrating the effectiveness of the proposed MFVNet.

关键词： semantic segmentation remote sensing image (RSI) field-of-view (FOV) adaptive fusion convolutional neural network

Electro-assisted regeneration of ion exchange resins

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Frontiers of Environmental Science & Engineering 2008年第4期2卷 410-414页

作者： Zhigang liU Ying WANG yansheng li Hui CHANG School of Environmental&Chemical Engineering Dalian Jiaotong UniversityDalian 116021China

Electro-assisted regeneration(EAR)for the mixed bed of strongly acidic cation and weakly basic anion exchange resins with the Al(OH)_(3) suspension in a three-compartment cell was *** desalination experiments were carried out to evaluate the characteristic of the regenerated mixed *** results showed that the efficiency of resin regeneration was strictly dependent on the voltage,regeneration time,and feed regenerant flow *** amount of the effluent reached 50 times the volume of the resins bed,and the conductivity was less than 1.0 ms/*** to the conventional ER,the total effluent volume of EAR was about 1000 mL more than that of ER under the same conditions,and the outlet conductivity was significantly *** desalination and regeneration reaction mechanisms of the mixed resins indicated the regeneration efficiency of resin with Al(OH)_(3) as the regenerant was much higher than that with H2O.

关键词： electro-assisted regeneration(EAR) Al form resins desalination Al(OH)_(3)

Temporal variation of soil carbon stock and its controlling factors over the last two decades on the southern Song-nen Plain,Heilongjiang Province

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Geoscience Frontiers 2010年第1期1卷 125-132页

作者： Xueqi Xia Zhongfang Yang Yan liao Yujun Cui yansheng li School of Earth Sciences and Resources China University of Geosciences Beijing 100083 China Heilongjiang Institute of Geological Survey Harbin 150036 China

Against the current background of global climate change, the study of variations in the soil carbon pool and its controlling factors may aid in the evaluation of soil＇s role in the mitigation or enhancement of greenhouse gas. This paper studies spatial and temporal variation in the soil carbon pool and their controlling factors in the southern Song-nen Plain in Heilongjiang Province, using soil data collected over two distinct periods by the Multi-purpose Regional Geochemical Survey in 2005-2007, and another soil survey conducted in 1982-1990. The study area is a carbon source of 1479 t/km2 and in the past 20 years, from the 1980s until 2005, the practical carbon emission from the soil was 0.12 Gt. Temperature, which has been found to be linearly correlated to soil organic carbon, is the domi- nant climatologic factor controlling soil organic carbon contents. Our study shows that in the relevant area and time period the potential loss of soil organic carbon caused by rising temperatures was 0.10 Gt, the potential soil carbon emission resulting from land-use change was 0.09 Gt, and the combined potential loss of soil carbon （0.19 Gt） caused by warming and land-use change is comparable to that of fossil fuel combustion （0.21 Gt）. Due to the time delay in soil carbon pool variation, there is still 0.07 Gt in the potential emission caused by warming and land-use change that will be gradually released in the future.

关键词： The southern Song-nen Plain in Heilongjiang Province Soil carbon pool Spatial and temporal variation Carbon cycle

Coupling changes of soil functional gene abundances and extracellular enzyme activities across the diagnostic horizons of agricultural Isohumosols

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Pedosphere 2024年第3期34卷 540-552页

作者： Zhuxiu liU Haidong GU Xiaojing HU Zhenhua YU yansheng li Junjie liU Jian JIN Xiaobing liU Guanghua WANG State Key Laboratory of Black Soils Conservation and Utilization Northeast Institute of Geography and AgroecologyChinese Academy of SciencesHarbin 150081(China) University of Chinese Academy of Sciences Beijing 100049(China)

Soil functional microbial taxa and extracellular enzymes are involved in a variety of biogeochemical cycling *** many studies have revealed the vertical change patterns of microbial communities along soil profile,the general understanding of the coupling changes in the functional gene abundances(FGAs)and extracellular enzyme activities(EEAs)in soil profiles is still limited,which hinders us from revealing soil ecosystem ***,we comparatively investigated the FGAs and EEAs in the diagnostic A,B,and C horizons of soil profiles obtained from two suborders of Isohumosols(Mollisols),Ustic and Udic Isohumosols,in Northeast China based on quantitative real-time polymerase chain reaction and standard fluorometric techniques,*** distribution patterns of both FGAs and EEAs significantly distinguished by the two soil suborders and were also separated from A to C ***,the variations of EEAs and FGAs were greater in Udic Isohumosols compared to Ustic Isohumosols along soil profiles,and greater changes were observed in C horizon than in A *** FGAs and EEAs correspondently decreased along the soil ***,when normalized by soil organic carbon,the specific EEAs significantly increased in deep soil horizons,suggesting that microorganisms will input more resources to the production of enzymes to ensure microbial nutrient requirements under resource *** importantly,we revealed that soil microbial nutrient demands were limited by carbon(C)and phosphorus(P),and the C and P limitations significantly increased along soil profiles with a greater C limitation observed in Ustic Isohumosols than in Udic ***,our findings provided solid evidence showing the links between FGAs,EEAs,and microbial nutrient limitations,which would be helpful for a better understanding of the ecosystem processes in soil profiles.

关键词： ecoenzymatic stoichiometry microbial nutrient limitation microbial nutrient requirement Mollisols soil ecosystem process soil profile

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丁二烯装置溶剂精制塔的设计

石油化工 2006年第10期35卷 980-982页

作者：李延生上海惠生化工工程有限公司上海201203

根据丁二烯装置溶剂精制塔的特点,提出了溶剂精制塔的计算模型,采用PRO/Ⅱ软件对溶剂精制塔进行了计算,计算结果与设计值基本吻合。溶剂精制塔宜采用浮阀板式塔,并设计了塔的结构。实际操作中,塔板上不能保持适宜的液面高度,针对这一问... 详细信息

根据丁二烯装置溶剂精制塔的特点,提出了溶剂精制塔的计算模型,采用PRO/Ⅱ软件对溶剂精制塔进行了计算,计算结果与设计值基本吻合。溶剂精制塔宜采用浮阀板式塔,并设计了塔的结构。实际操作中,塔板上不能保持适宜的液面高度,针对这一问题,采取密封塔板边缘和装配间隙的措施,并将F1型浮阀改为A1型浮阀,取得了很好的效果。运行结果表明,溶剂精制塔的设计是成功的,对低处理量的小直径板式塔的设计具有一定的参考价值。

关键词：精馏塔板式塔模拟计算塔板设计丁二烯溶剂

Nutritional quality of different potassium efficiency types of vegetable soybean as affected by potassium nutrition

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Food Quality and Safety 2022年第2期6卷 214-224页

作者： Changkai liu Xue Wang Heng Chen Houyu Xia Bingjie Tu yansheng li Qiuying Zhang Xiaobing liu Key Laboratory of Mllisols Agroecology Northeast Institute of Geography and AgroecologyChinese Academy of SciencesHarbinChina University of Chinese Academy of Sciences BeiingChina Innovation Academy for Seed Design Chinese Academy of SciencesHarbinChina Mollisols Protection and Monitoring Center Jilin Soil and Fertilizer StationJilinChina

Pot experiments were conducted in 2017,2019,and 2020 to examine the effects of potassium nutrition on the nutritional components of vege-table soybeans with different K efficiency at immature and mature *** vegetable soybean varieties with higher K efficiency and two varieties with lower K efficiency were studied in the low available K soil under the conditions of no K and normal K *** results indicated that almost all nutritional components in vegetable soybean were affected by K,genotypes,interannual differences,and their *** general,no K fertilization increased protein and amino acid concentrations but decreased oil,soluble sugar,sucrose,K,Mg,and Fe concentrations in immature and mature vegetable *** sensitivity of nutritional components to K nutrition differed among *** instance,K high-efficiency varieties generally exhibited higher protein and amino acid concentrations without K application.K high-efficiency vegetable soybeans are low-K tolerance varieties to *** results of this study provide insights for high yield and quality vegetable soybean breeding against soil K deficiency.

关键词： Vegetable soybean amino acids isflavones sucrose potassium nutritional quality

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减压深拔工艺的开发与应用

石油炼制与化工 2010年第10期41卷 12-16页

作者：李炎生中国石化武汉分公司武汉430082

介绍了中国石化武汉分公司5Mt/a常减压蒸馏装置减压深拔技术的开发及设计特点,并对装置开工后的标定数据进行了计算分析与对比。结果表明,装置的生产运行达到了设计的预期目的,在保证产品质量的同时直馏蜡油收率提高了约2.38个百分点,... 详细信息

介绍了中国石化武汉分公司5Mt/a常减压蒸馏装置减压深拔技术的开发及设计特点,并对装置开工后的标定数据进行了计算分析与对比。结果表明,装置的生产运行达到了设计的预期目的,在保证产品质量的同时直馏蜡油收率提高了约2.38个百分点,按月加工原油350kt计算,直馏蜡油产量增加8300t/月,月增效约400万元,取得了良好的社会效益和经济效益。

关键词：常减压蒸馏装置减压深拔拔出率减压塔