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Differences and identification on multi-time hydrocarbon generation of carboniferous-permian coaly source rocks in the Huanghua Depression,Bohai Bay Basin
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作者 Jin-Jun Xu Xian-Gang Cheng +5 位作者 Shu-Nan Peng Jun-Cai Jiang Qi-Long Wu Da Lou Fu-Qi Cheng La-Mei Lin 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期765-776,共12页
Coal is a solid combustible mineral,and coal-bearing strata have important hydrocarbon generation potential and contribute to more than 12%of the global hydrocarbon resources.However,the deposition and hydrocarbon evo... Coal is a solid combustible mineral,and coal-bearing strata have important hydrocarbon generation potential and contribute to more than 12%of the global hydrocarbon resources.However,the deposition and hydrocarbon evolution process of ancient coal-bearing strata is characterized by multiple geological times,leading to obvious distinctions in their hydrocarbon generation potential,geological processes,and production,which affect the evaluation and exploration of hydrocarbon resources derived from coaly source rocks worldwide.This study aimed to identify the differences on oil-generated parent macerals and the production of oil generated from different coaly source rocks and through different oil generation processes.Integrating with the analysis of previous tectonic burial history and hydrocarbon generation history,high-temperature and high-pressure thermal simulation experiments,organic geochemistry,and organic petrology were performed on the Carboniferous-Permian(C-P)coaly source rocks in the Huanghua Depression,Bohai Bay Basin.The oil-generated parent macerals of coal's secondary oil generation process(SOGP)were mainly hydrogen-rich collotelinite,collodetrinite,sporinite,and cutinite,while the oil-generated parent macerals of tertiary oil generation process(TOGP)were the remaining small amount of hydrogen-rich collotelinite,sporinite,and cutinite,as well as dispersed soluble organic matter and unexhausted residual hydrocarbons.Compared with coal,the oil-generated parent macerals of coaly shale SOGP were mostly sporinite and cutinite.And part of hydrogen-poor vitrinite,lacking hydrocarbon-rich macerals,and macerals of the TOGP,in addition to some remaining cutinite and a small amount of crude oil and bitumen from SOGP contributed to the oil yield.The results indicated that the changes in oil yield had a good junction between SOGP and TOGP,both coal and coaly shale had higher SOGP aborted oil yield than TOGP starting yield,and coaly shale TOGP peak oil yield was lower than SOGP peak oil yield.There were significant differences in saturated hydrocarbon and aromatic parameters in coal and coaly shale.Coal SOGP was characterized by a lower Ts/Tm and C31-homohopane22S/(22S+22R)and a higher Pr/n C17compared to coal TOGP,while the aromatic parameter methyl dibenzothiophene ratio(MDR)exhibited coaly shale TOGP was higher than coaly shale SOGP than coaly TOGP than coaly SOGP,and coal trimethylnaphthalene ratio(TNR)was lower than coaly shale TNR.Thus,we established oil generation processes and discriminative plates.In this way,we distinguished the differences between oil generation parent maceral,oil generation time,and oil production of coaly source rocks,and therefore,we provided important support for the evaluation,prediction,and exploration of oil resources from global ancient coaly source rocks. 展开更多
关键词 Thermal simulation multi-time oil generation processes Coaly source rock CARBONIFEROUS-PERMIAN Huanghua Depression
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Multi-Time Scale Optimal Scheduling of a Photovoltaic Energy Storage Building System Based on Model Predictive Control
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作者 Ximin Cao Xinglong Chen +2 位作者 He Huang Yanchi Zhang Qifan Huang 《Energy Engineering》 EI 2024年第4期1067-1089,共23页
Building emission reduction is an important way to achieve China’s carbon peaking and carbon neutrality goals.Aiming at the problem of low carbon economic operation of a photovoltaic energy storage building system,a ... Building emission reduction is an important way to achieve China’s carbon peaking and carbon neutrality goals.Aiming at the problem of low carbon economic operation of a photovoltaic energy storage building system,a multi-time scale optimal scheduling strategy based on model predictive control(MPC)is proposed under the consideration of load optimization.First,load optimization is achieved by controlling the charging time of electric vehicles as well as adjusting the air conditioning operation temperature,and the photovoltaic energy storage building system model is constructed to propose a day-ahead scheduling strategy with the lowest daily operation cost.Second,considering inter-day to intra-day source-load prediction error,an intraday rolling optimal scheduling strategy based on MPC is proposed that dynamically corrects the day-ahead dispatch results to stabilize system power fluctuations and promote photovoltaic consumption.Finally,taking an office building on a summer work day as an example,the effectiveness of the proposed scheduling strategy is verified.The results of the example show that the strategy reduces the total operating cost of the photovoltaic energy storage building system by 17.11%,improves the carbon emission reduction by 7.99%,and the photovoltaic consumption rate reaches 98.57%,improving the system’s low-carbon and economic performance. 展开更多
关键词 Load optimization model predictive control multi-time scale optimal scheduling photovoltaic consumption photovoltaic energy storage building
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面向遥感图像场景分类的LAG-MANet模型 被引量:1
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作者 王威 郑薇 王新 《测绘学报》 EI CSCD 北大核心 2024年第7期1371-1383,共13页
遥感图像分类过程中,局部信息与全局信息至关重要。目前,遥感图像分类的方法主要包括卷积神经网络(CNN)及Transformer。CNN在局部信息提取方面具有优势,但在全局信息提取方面有一定的局限性。相比之下,Transformer在全局信息提取方面表... 遥感图像分类过程中,局部信息与全局信息至关重要。目前,遥感图像分类的方法主要包括卷积神经网络(CNN)及Transformer。CNN在局部信息提取方面具有优势,但在全局信息提取方面有一定的局限性。相比之下,Transformer在全局信息提取方面表现出色,但计算复杂度高。为提高遥感图像场景分类性能,降低复杂度,设计了LAG-MANet纯卷积网络。该网络既关注局部特征,又关注全局特征,并且考虑了多尺度特征。输入图像被预处理后,首先采用多分支扩张卷积模块(MBDConv)提取多尺度特征;然后依次进入网络的4个阶段,在每个阶段采用并行双域特征融合模块(P2DF)分支路提取局部、全局特征并进行融合;最后先经过全局平均池化、再经过全连接层输出分类标签。LAG-MANet在WHU-RS19数据集、SIRI-WHU数据集及RSSCN7数据集上的分类准确率分别为97.76%、97.04%、97.18%。试验结果表明,在3个具有挑战性的公开遥感数据集上,LAG-MANet更具有优越性。 展开更多
关键词 遥感图像 场景分类 CNN lag-MANet
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阿尔茨海默病中免疫检查位点LAG3的研究
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作者 孟凌云 段冉 陈静 《中国免疫学杂志》 CAS CSCD 北大核心 2024年第2期273-277,共5页
目的:探讨免疫检查位点基因LAG3在阿尔茨海默病(AD)中的作用和意义。方法:对GEO(https://www.ncbi.nlm.nih.gov/geo/)数据库中AD患者脑组织测序数据集GSE48350和血液测序数据集GSE140829进行分析,采用CIBERSORT计算脑组织中的免疫细胞评... 目的:探讨免疫检查位点基因LAG3在阿尔茨海默病(AD)中的作用和意义。方法:对GEO(https://www.ncbi.nlm.nih.gov/geo/)数据库中AD患者脑组织测序数据集GSE48350和血液测序数据集GSE140829进行分析,采用CIBERSORT计算脑组织中的免疫细胞评分,并观察LAG3的表达量变化;使用人源Aβ1-42淀粉样蛋白诱导小鼠海马神经元细胞系HT22作为AD细胞模型,RT-PCR检测LAG3的表达量变化。通过GSEA分析研究与LAG3直接相关的通路,String网站构建PPI网络,发现与LAG3相互作用的基因,最后通过KEGG和GO分析这些基因的生物学功能。结果:AD患者脑组织中免疫细胞与健康人存在较大差异,AD患者脑组织和血液中LAG3水平均高于健康人,AD细胞模型中LAG3的表达量也增高。结论:AD脑组织中免疫细胞构成与健康人存在差异,AD脑组织中未激活的记忆CD4^(+)T细胞和单核细胞的比例较高,激活的NK细胞偏低,且免疫检查位点LAG3的表达量增高,其可能与CD4细胞有关,也与免疫细胞的活化和调节存在联系。 展开更多
关键词 阿尔茨海默病 lag3 免疫检查位点 CD4 免疫细胞评分
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Bio-Inspired Optimal Dispatching of Wind Power Consumption Considering Multi-Time Scale Demand Response and High-Energy Load Participation 被引量:1
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作者 Peng Zhao Yongxin Zhang +2 位作者 Qiaozhi Hua Haipeng Li Zheng Wen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第2期957-979,共23页
Bio-inspired computer modelling brings solutions fromthe living phenomena or biological systems to engineering domains.To overcome the obstruction problem of large-scale wind power consumption in Northwest China,this ... Bio-inspired computer modelling brings solutions fromthe living phenomena or biological systems to engineering domains.To overcome the obstruction problem of large-scale wind power consumption in Northwest China,this paper constructs a bio-inspired computer model.It is an optimal wind power consumption dispatching model of multi-time scale demand response that takes into account the involved high-energy load.First,the principle of wind power obstruction with the involvement of a high-energy load is examined in this work.In this step,highenergy load model with different regulation characteristics is established.Then,considering the multi-time scale characteristics of high-energy load and other demand-side resources response speed,a multi-time scale model of coordination optimization is built.An improved bio-inspired model incorporating particle swarm optimization is applied to minimize system operation and wind curtailment costs,as well as to find the most optimal energy configurationwithin the system.Lastly,we take an example of regional power grid in Gansu Province for simulation analysis.Results demonstrate that the suggested scheduling strategy can significantly enhance the wind power consumption level and minimize the system’s operational cost. 展开更多
关键词 Biological system multi-time scale wind power consumption demand response bio-inspired computermodelling particle swarm optimization
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Effect of different cold air intensities and their lagged effects on outpatient visits for respiratory illnesses in Handan in different seasons 被引量:1
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作者 Xingshan Zhang Guiqin Fu +4 位作者 Liang Zhao Ji Wang Caimeng Liang Juanhuai Wang Meng Li 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第1期39-44,共6页
本文利用2016年到2019年邯郸市气象要素和呼吸系统疾病门诊数据,分析了不同季节不同强度的冷空气过程及其对呼吸系统疾病的影响,结果显示:尽管呼吸系统疾病在冬季高发,夏季最低,但冷空气对呼吸系统疾病的影响在夏,春季最大,就诊人数分... 本文利用2016年到2019年邯郸市气象要素和呼吸系统疾病门诊数据,分析了不同季节不同强度的冷空气过程及其对呼吸系统疾病的影响,结果显示:尽管呼吸系统疾病在冬季高发,夏季最低,但冷空气对呼吸系统疾病的影响在夏,春季最大,就诊人数分别在冷空气日后两天和五天增加18.4%和13.3%,而冬季就诊人数在冷空气日后三天仅增加3.2%.冷空气对疾病影响的滞后时间在夏,秋和冬季随冷空气强度的增加而减少,而春季的滞后时间总是很长.这些发现可为科学应对气候异常导致的人群健康风险提供针对性依据. 展开更多
关键词 冷空气过程 降温幅度 呼吸系统疾病 滞后效应
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Cross-Correlation between Global Temperature and Atmospheric CO2 with a Temperature-Leading Time Lag
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作者 Masaharu Nishioka 《Atmospheric and Climate Sciences》 2024年第4期484-494,共11页
The temperature change and rate of CO2 change are correlated with a time lag, as reported in a previous paper. The correlation was investigated by calculating a correlation coefficient r of these changes for selected ... The temperature change and rate of CO2 change are correlated with a time lag, as reported in a previous paper. The correlation was investigated by calculating a correlation coefficient r of these changes for selected ENSO events in this study. Annual periodical increases and decreases in the CO2 concentration were considered, with a regular pattern of minimum values in August and maximum values in May each year. An increased deviation in CO2 and temperature was found in response to the occurrence of El Niño, but the increase in CO2 lagged behind the change in temperature by 5 months. This pattern was not observed for La Niña events. An increase in global CO2 emissions and a subsequent increase in global temperature proposed by IPCC were not observed, but an increase in global temperature, an increase in soil respiration, and a subsequent increase in global CO2 emissions were noticed. This natural process can be clearly detected during periods of increasing temperature specifically during El Niño events. The results cast strong doubts that anthropogenic CO2 is the cause of global warming. 展开更多
关键词 Global Warming Thermally-Induced CO2 Soil Respiration Cross-Correlation Coefficient Time lag El Niño
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胃窦癌组织中LAG-3 FGL1 MHC-Ⅱ的表达与预后的关系
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作者 戚颖 黄子祺 +2 位作者 别鸿宇 颜次慧 任秀宝 《中国肿瘤临床》 CAS CSCD 北大核心 2024年第2期64-69,共6页
目的:探索新型免疫检查点淋巴细胞激活基因3(lymphocyte-activation gene 3,LAG-3)、纤维蛋白原样蛋白1(fibrinogenlike protein 1,FGL1)、主要组织相容性复合体Ⅱ类分子(major histocompatibility complex classⅡ,MHC-Ⅱ)在胃窦癌(gas... 目的:探索新型免疫检查点淋巴细胞激活基因3(lymphocyte-activation gene 3,LAG-3)、纤维蛋白原样蛋白1(fibrinogenlike protein 1,FGL1)、主要组织相容性复合体Ⅱ类分子(major histocompatibility complex classⅡ,MHC-Ⅱ)在胃窦癌(gastric antral cancer,GAC)中的表达情况与预后的相关性。方法:收集2012年1月至2014年12月于天津医科大学肿瘤医院诊断为GAC的67例患者病理标本,分别进行石蜡切片制作,采用免疫组织化学法检测LAG-3、FGL1、MHC-Ⅱ三个指标的表达情况,并用统计学方法分析组间差异。采用Kaplan-Meier法评估LAG-3、FGL1、MHC-Ⅱ的表达水平与GAC患者预后之间的关系并绘制生存曲线。结果:GAC患者中,肿瘤大小<4 cm的患者和无淋巴结转移的患者LAG-3免疫细胞阳性率更高(P<0.05);女性患者MHC-Ⅱ免疫细胞阳性率更高(P<0.05)。免疫细胞中LAG-3、MHC-Ⅱ高表达的患者总生存期(overall survival,OS)较好(P<0.05);肿瘤细胞中MHC-Ⅱ高表达的患者OS、无病生存期(disease-free survival,DFS)较差(P<0.05);而FGL1在免疫细胞和肿瘤细胞中的表达与OS、DFS无显著相关性(P>0.05)。结论:GAC患者LAG-3、MHC-Ⅱ在不同区域的表达量存在差异,GAC患者LAG-3及其配体在免疫细胞的表达对预后产生积极影响,提示免疫细胞中LAG-3/MHC-Ⅱ可以作为GAC患者预后标志物,为临床个体化免疫治疗提供新的依据。 展开更多
关键词 胃窦癌 淋巴细胞激活基因3 纤维蛋白原样蛋白1 主要组织相容性复合体Ⅱ类分子 生存 预后
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宫颈癌组织中EZH2、LAG-3表达及与病理特征的相关性
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作者 李学敏 吴莉莉 +1 位作者 方琴 田静 《齐齐哈尔医学院学报》 2024年第19期1807-1812,共6页
目的分析宫颈癌组织中Zeste增强子同源物2(EZH2)、淋巴细胞激活基因-3(LAG-3)表达及与病理特征的相关性。方法选择2013年5月—2023年11月本院收治的54例经病理确诊为宫颈癌并行宫颈根治术的患者作为观察组;并选取同期1477例宫颈良性病... 目的分析宫颈癌组织中Zeste增强子同源物2(EZH2)、淋巴细胞激活基因-3(LAG-3)表达及与病理特征的相关性。方法选择2013年5月—2023年11月本院收治的54例经病理确诊为宫颈癌并行宫颈根治术的患者作为观察组;并选取同期1477例宫颈良性病变患者作为对照组。比较两组患者EZH2、LAG-3表达水平,比较不同宫颈癌病理特征患者组织EZH2、LAG-3表达水平差异,分别采用单因素与多因素Logistic回归分析法筛选造成宫颈癌术后患者预后不良的危险因素。结果观察组EZH2、LAG-3阳性表达率相较于对照组均更高(P<0.05);临床分期在Ⅲ或Ⅳ期、分化程度为低中分化、浸润深度>3 mm、已发生脉管浸润和淋巴转移患者的EZH2、LAG-3阳性表达率相较于临床分期在Ⅰ或Ⅱ期、分化程度为高分化、浸润深度≤3 mm、未发生脉管浸润和淋巴转移的宫颈癌患者更高(P<0.05);随访6个月后,54例患者中6例患者发生预后不良,预后不良发生率为11.11%(6/54);预后不良组低中分化、浸润深度>3 mm、淋巴转移阳性、EZH2和LAG-3阳性表达占比相较于预后良好组均更高(P<0.05);(4)Logistic回归分析结果显示,低中分化程度、淋巴转移阳性、EZH2和LAG-3阳性表达是造成宫颈癌术后患者出现预后不良的危险因素(P<0.05)。结论宫颈癌患者组织EZH2、LAG-3阳性表达率较高,其表达水平与临床分期、分化程度、浸润深度、脉管浸润、淋巴转移病理特征密切相关;低中分化程度、淋巴转移阳性、EZH2和LAG-3阳性表达是造成宫颈癌患者预后不良的危险因素,临床在收治上述患者时应提前采取干预措施,谨防预后不良。 展开更多
关键词 宫颈癌 Zeste增强子同源物2 淋巴细胞激活基因-3 病理特征 相关性 预后
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Decay rates and time lags of heat conduction in building construction under field conditions
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作者 彭昌海 吴智深 +1 位作者 陈振乾 李敏 《Journal of Southeast University(English Edition)》 EI CAS 2010年第2期249-253,共5页
The field measurements of decay rates and time lags of heat conduction in a building construction taken in Nanjing during the summer of 2001 are presented.The decay rates and time lags are calculated according to the ... The field measurements of decay rates and time lags of heat conduction in a building construction taken in Nanjing during the summer of 2001 are presented.The decay rates and time lags are calculated according to the frequency responses of the heat absorbed by the room's internal surfaces,inside surface temperature,indoor air temperature and outdoor synthetic temperature.The measured results match very well with the theoretical results of the zeroth and the first order values of the decay rates and time lags of heat conduction in the building construction,but the difference between the measured values and the theoretical values for the second order is too great to be accepted.It is therefore difficult to accurately test the second order value.However,it is still advisable to complete the analysis using the zeroth-and the first-orders values of the decay rates and time lags of heat conduction in building construction under field conditions,because in these cases the decay rates of heat conduction reach twenty which meets the requirements of engineering plans. 展开更多
关键词 decay rates time lags heat conduction building construction FIELD
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Low-carbon generation expansion planning considering uncertainty of renewable energy at multi-time scales 被引量:14
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作者 Yuanze Mi Chunyang Liu +2 位作者 Jinye Yang Hengxu Zhang Qiuwei Wu 《Global Energy Interconnection》 EI CAS CSCD 2021年第3期261-272,共12页
With the development of carbon electricity,achieving a low-carbon economy has become a prevailing and inevitable trend.Improving low-carbon expansion generation planning is critical for carbon emission mitigation and ... With the development of carbon electricity,achieving a low-carbon economy has become a prevailing and inevitable trend.Improving low-carbon expansion generation planning is critical for carbon emission mitigation and a lowcarbon economy.In this paper,a two-layer low-carbon expansion generation planning approach considering the uncertainty of renewable energy at multiple time scales is proposed.First,renewable energy sequences considering the uncertainty in multiple time scales are generated based on the Copula function and the probability distribution of renewable energy.Second,a two-layer generation planning model considering carbon trading and carbon capture technology is established.Specifically,the upper layer model optimizes the investment decision considering the uncertainty at a monthly scale,and the lower layer one optimizes the scheduling considering the peak shaving at an hourly scale and the flexibility at a 15-minute scale.Finally,the results of different influence factors on low-carbon generation expansion planning are compared in a provincial power grid,which demonstrate the effectiveness of the proposed model. 展开更多
关键词 Renewable energy multi-time scales UNCERTAINTY Low-carbon Generation planning
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Effective Iterated Greedy Algorithm for Flow-Shop Scheduling Problems with Time lags 被引量:4
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作者 Ning ZHAO Song YE +1 位作者 Kaidian LI Siyu CHEN 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第3期652-662,共11页
Flow shop scheduling problem with time lags is a practical scheduling problem and attracts many studies. Permutation problem(PFSP with time lags) is concentrated but non-permutation problem(non-PFSP with time lags... Flow shop scheduling problem with time lags is a practical scheduling problem and attracts many studies. Permutation problem(PFSP with time lags) is concentrated but non-permutation problem(non-PFSP with time lags) seems to be neglected. With the aim to minimize the makespan and satisfy time lag constraints, efficient algo- rithms corresponding to PFSP and non-PFSP problems are proposed, which consist of iterated greedy algorithm for permutation(IGTLP) and iterated greedy algorithm for non-permutation (IGTLNP). The proposed algorithms are verified using well-known simple and complex instances of permutation and non-permutation problems with various time lag ranges. The permutation results indicate that the proposed IGTLP can reach near optimal solution within nearly 11% computational time of traditional GA approach. The non-permutation results indicate that the proposed IG can reach nearly same solution within less than 1% com- putational time compared with traditional GA approach. The proposed research combines PFSP and non-PFSP together with minimal and maximal time lag consideration, which provides an interesting viewpoint for industrial implementation. 展开更多
关键词 PERMUTATION Non-permutation Flow shopTime lags . Makespan Iterated greedy algorithm
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Impact of time lags on diurnal estimates of canopy transpiration and canopy conductance from sap-flow measurements of Populus cathayana in the Qinghai–Tibetan Plateau 被引量:3
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作者 Hui Wang Kangning He +4 位作者 Runjie Li Zhuping Sheng Yun Tian Jun Wen Bo Chang 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第3期481-490,共10页
Recently, canopy transpiration (Ec) has been often estimated by xylem sap-flow measurements. However, there is a significant time lag between sap flow measured at the base of the stem and canopy transpiration due to... Recently, canopy transpiration (Ec) has been often estimated by xylem sap-flow measurements. However, there is a significant time lag between sap flow measured at the base of the stem and canopy transpiration due to the capacitive exchange between the transpiration stream and stem water storage. Significant errors will be introduced in canopy conductance (gc) and canopy transpiration estimation if the time lag is neglected. In this study, a cross-correlation analysis was used to quantify the time lag, and the sap flowbased transpiration was measured to pararneterize Jarvistype models of gc and thus to simulate Ec of Populus cathayana using the Penman-Monteith equation. The results indicate that solar radiation (Rs) and vapor pressure deficit (VPD) are not fully coincident with sap flow and have an obvious lag effect; the sap flow lags behind Rs and precedes VPD, and there is a 1-h time shift between Eo and sap flow in the 30-min interval data set. A parameterized Jarvis-type gc model is suitable to predict P. cathayana transpiration and explains more than 80% of the variation observed in go, and the relative error was less than 25%, which shows a preferable simulation effect. The root mean square error (RMSEs) between the predicted and measured Ec were 1.91×10^-3 (with the time lag) and 3.12×10^-3cm h^-1 (without the time lag). More importantly, Ec simulation precision that incorporates time lag is improved by 6% compared to the results without the time lag, with the mean relative error (MRE) of only 8.32% and the mean absolute error (MAE) of 1.48 × 10^-3 cm h^-1. 展开更多
关键词 Canopy transpiration Model - Populuscathayana Qinghai-Tibetan Plateau Sap flow Time lags
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Boundary Control Problem of Infinite Order Distributed Hyperbolic Systems Involving Time Lags 被引量:2
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作者 Bahaa Gaber Mohamed 《Intelligent Control and Automation》 2012年第3期211-221,共11页
Various optimal boundary control problems for linear infinite order distributed hyperbolic systems involving constant time lags are considered. Constraints on controls are imposed. Necessary and sufficient optimality ... Various optimal boundary control problems for linear infinite order distributed hyperbolic systems involving constant time lags are considered. Constraints on controls are imposed. Necessary and sufficient optimality conditions for the Neumann problem with the quadratic performance functional are derived. 展开更多
关键词 BOUNDARY CONTROL (n × n) Hyperbolic Systems Time lags DISTRIBUTED CONTROL Problems NEUMANN Conditions Existence and UNIQUENESS of Solutions Infinite Order Operator
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Multi-time scale analysis of precipitation variation in Guyuan, China:1957-2005 被引量:1
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作者 Liu Delin Li Bicheng 《Ecological Economy》 2008年第4期512-518,共7页
Morlet wavelet transformation is used in this paper to analyze the multi time scale characteristics of pre cipitation data series from 1957 to 2005 in Guyuan region.The results showed that(1) the annual precipitation ... Morlet wavelet transformation is used in this paper to analyze the multi time scale characteristics of pre cipitation data series from 1957 to 2005 in Guyuan region.The results showed that(1) the annual precipitation evo lution process had obvious multi time scale variation characteristics of 15 25 years,7 12 years and 3 6 years,and different time scales had different oscillation energy densities;(2) the periods at smaller time scales changed more frequently,which often nested in a biggish quasi periodic oscillations,so the concrete time domain should be ana lyzed if necessary;(3) the precipitation had three main periods(22 year,9 year and 4 year) and the 22 year period was especially outstanding,and the analysis of this main period reveals that the precipitation would be in a relative high water period until about 2012. 展开更多
关键词 Precipitation variation multi-time scale Wavelet analysis Guyuan region Loess Plateau
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A New Smoothing Approach with Diverse Fixed-lags Based on Target Motion Model
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作者 Chen Li, Chong-Zhao Han, Hong-Yan Zhu Electronic and Information Engineering, Xi’an Jiaotong University, Xi’an 710049, PRC 《International Journal of Automation and computing》 EI 2006年第4期425-430,共6页
Recently, lots of smoothing techniques have been presented for maneuvering target tracking. Interacting multiple model-probabilistic data association (IMM-PDA) fixed-lag smoothing algorithm provides an efficient sol... Recently, lots of smoothing techniques have been presented for maneuvering target tracking. Interacting multiple model-probabilistic data association (IMM-PDA) fixed-lag smoothing algorithm provides an efficient solution to track a maneuvering target in a cluttered environment. Whereas, the smoothing lag of each model in a model set is a fixed constant in traditional algorithms. A new approach is developed in this paper. Although this method is still based on IMM-PDA approach to a state augmented system, it adopts different smoothing lag according to diverse degrees of complexity of each model. As a result, the application is more flexible and the computational load is reduced greatly. Some simulations were conducted to track a highly maneuvering target in a cluttered environment using two sensors. The results illustrate the superiority of the proposed algorithm over comparative schemes, both in accuracy of track estimation and the computational load. 展开更多
关键词 Maneuvering target tracking smoothing lag interacting multiple model (IMM) probabilistic data association(PDA)
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The Legal Conflicts, the Legislative Vacancies and the Legislative Lags in the Chinese Environmental Legal System
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作者 Yue Zhu 《Journal of Geoscience and Environment Protection》 2019年第3期12-45,共34页
The inconsistency and disharmony in China’s environmental legal system are seriously undermining the authority and effectiveness of environmental laws, making it hard to achieve the national environmental legislative... The inconsistency and disharmony in China’s environmental legal system are seriously undermining the authority and effectiveness of environmental laws, making it hard to achieve the national environmental legislative goals. It is found in this study that at least 18 administrative regulations and rules conflict with the five recently-revised environmental laws. The legislative vacancy rate of province-level environmental laws reaches 27.8%, and that of city-level environmental laws in the major cities reaches 59.7%. Besides, 66% of the local including both province-level and city-level environmental laws have the problem of legislative lags, with an average lag of 2547.8 days. In addition, there are many legal conflicts between national environmental laws and local environmental laws. In order to help China to build a harmonious and unified environmental legal system, some suggestions are proposed in this study, including comprehensively examining the lower-level environmental laws, strengthening the leading role of local people’s congresses in environmental legislation, improving the construction of filing and review mechanism, and optimizing the mechanisms for information disclosure and public participation. 展开更多
关键词 China The Environmental LEGAL System LEGAL CONFLICT LEGISLATIVE VACANCY LEGISLATIVE lag
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靶向淋巴细胞激活基因3(LAG-3)纳米抗体的筛选与活性分析 被引量:1
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作者 文蕊鑫 陈玥雯 +3 位作者 杨紫薇 闫凤英 李卿 武卫党 《细胞与分子免疫学杂志》 CAS CSCD 北大核心 2023年第11期1024-1031,共8页
目的建立淋巴细胞激活基因3(LAG-3)免疫噬菌体纳米抗体文库,获得高特异性和亲和力的抗LAG-3纳米抗体,并鉴定其功能活性。方法采用人LAG-3蛋白免疫羊驼,获取外周血cDNA;通过巢式PCR获得纳米抗体基因,构建至pComb3XSS质粒,电转至大肠杆菌X... 目的建立淋巴细胞激活基因3(LAG-3)免疫噬菌体纳米抗体文库,获得高特异性和亲和力的抗LAG-3纳米抗体,并鉴定其功能活性。方法采用人LAG-3蛋白免疫羊驼,获取外周血cDNA;通过巢式PCR获得纳米抗体基因,构建至pComb3XSS质粒,电转至大肠杆菌XL1-Blue中构建纳米抗体噬菌体免疫文库,并对文库进行质量分析。通过噬菌体展示技术筛选抗LAG-3特异性纳米抗体,通过第二代基因测序技术获得纳米抗体的基因序列。将目的序列构建到大肠杆菌BL21(DE3)周质表达载体pET-22b(+)中进行抗体表达,Prism A柱进行纯化,通过高效液相色谱-质谱分析(HPLC-MS)、ELISA、Western blot法和表面等离子共振技术(SPR)进行抗体性质和功能分析。结果构建的纳米抗体噬菌体免疫文库的库容为7.20×10^(8)菌落形成单位(CFU),序列分析文库多样性良好,经过4轮淘筛后获得3条具有不同氨基酸序列的抗LAG-3纳米抗体,分别为重链抗体重链可变区结构域-L1-3(VHH-L1-3)、VHH-L3-2和VHH-L13-2,纳米抗体表达纯化后纯度在95%以上,三种抗体均可以与重组人LAG-3蛋白进行特异性结合;其中VHH-L13-2抗体的亲和力指数KD值为3.971×10^(-9)mol/L,且对于LAG-3和纤维蛋白原样蛋白1(FGL-1)的结合具有抑制作用,半数抑制浓度(IC_(50))值为15.58 nmol/L。结论成功构建了LAG-3纳米抗体噬菌体免疫文库,筛选获得了特异性好、亲和力高的LAG-3纳米抗体,且对于LAG-3与其配体的结合具有一定的抑制作用。 展开更多
关键词 纳米抗体 淋巴细胞激活基因3(lag-3) 噬菌体展示技术 原核表达
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Market-based control strategy for long-span structures considering the multi-time delay issue
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作者 Li Hongnan Song Jianzhu Li Gang 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2017年第1期153-164,共12页
To solve the different time delays that exist in the control device installed on spatial structures, in this study, discrete analysis using a 2N precise algorithm was selected to solve the multi-time-delay issue for l... To solve the different time delays that exist in the control device installed on spatial structures, in this study, discrete analysis using a 2N precise algorithm was selected to solve the multi-time-delay issue for long-span structures based on the market-based control (MBC) method. The concept of interval mixed energy was introduced from computational structural mechanics and optimal control research areas, and it translates the design of the MBC multi-time-delay controller into a solution for the segment matrix. This approach transforms the serial algorithm in time to parallel computing in space, greatly improving the solving efficiency and numerical stability. The designed controller is able to consider the issue of time delay with a linear controlling force combination and is especially effective for large time-delay conditions. A numerical example of a long-span structure was selected to demonstrate the effectiveness of the presented controller, and the time delay was found to have a significant impact on the results. 展开更多
关键词 market based control multi-time delay interval mixed energy 2N precise algorithm discrete system
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Research on multi-time scale doubly-fed wind turbine test system based on FPGA+CPU heterogeneous calculation
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作者 Qing Mu Xing Zhang +3 位作者 Xiaoxin Zhou Xiaowei Fan Yingmei Liu Dongbo Pan 《Global Energy Interconnection》 2019年第1期7-18,共12页
As the proportion of renewable energy increases, the interaction between renewable energy devices and the grid continues to enhance. Therefore, the renewable energy dynamic test in a power system has become more and m... As the proportion of renewable energy increases, the interaction between renewable energy devices and the grid continues to enhance. Therefore, the renewable energy dynamic test in a power system has become more and more important. Traditional dynamic simulation systems and digital-analog hybrid simulation systems are difficult to compromise on the economy, flexibility and accuracy. A multi-time scale test system of doubly fed induction generator based on FPGA+ CPU heterogeneous calculation is proposed in this paper. The proposed test system is based on the ADPSS simulation platform. The power circuit part of the test system is setup up using the EMT(electromagnetic transient simulation) simulation, and the control part uses the actual physical devices. In order to realize the close-loop testing for the physical devices, the power circuit must be simulated in real-time. This paper proposes a multi-time scale simulation algorithm, in which the decoupling component divides the power circuit into a large time scale system and a small time scale system in order to reduce computing effort. This paper also proposes the FPGA+CPU heterogeneous computing architecture for implementing this multitime scale simulation. In FPGA, there is a complete small time-scale EMT engine, which support the flexibly circuit modeling with any topology. Finally, the test system is connected to an DFIG controller based on Labview to verify the feasibility of the test system. 展开更多
关键词 Renewable energy gen erati on DOUBLY fed in duction generator ADPSS simulati on SYSTEM Wind turbine test SYSTEM multi-time scale FPGA+CPU
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