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A Novel Integrated Measure for Energy Market Efficiency

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Journal of Systems Science & Complexity 2020年第4期33卷 1108-1125页

作者： TANG ling lüHuiling YANG Fengmei Yu lean lI Jingjing School of Economics and Management Beihang UniversityBeijing 100191China School of Science Beijing University of Chemical TechnologyBeijing 100029China School of Economics and Management Beijing University of Chemical TechnologyBeijing 100029China School of Economics Capital University of Economics and BusinessBeijing 100070China

This paper formulates a novel integrated measure for energy market efficiency,by investigating different aspects of the market *** from most existing models focusing on one certain aspect,the novel measure especially takes into consideration the self-similarity(or system memo ability or long-term persistence)via fractality,the attractor properties in phase-space via chaos,and disorder state of data dynamics via *** the proposed method,the most popular data analysis techniques of multi-fractal detrended fluctuation analysis,correlation dimension,and sample entropy are respectively conducted on the market returns to capture the corresponding features,and the entropy weight method is then used to generate the final integrated *** il.ustration and verification,the proposed measure is applied to three typical energy markets *** empirical results find that natural gas market and crude oil market are much more efficient than carbon market.

关键词： fractal entropy il.ustration

土壤性质对小白菜吸收铬(Cr)的影响及预测模型研究

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农业机械学报 2018年第1期49卷 244-250页

作者：代允超吕亚敏吕家珑西北农林科技大学资源环境学院陕西杨凌712100 农业部植物营养与农业环境重点实验室陕西杨凌712100

采集我国15个省份理化性质差异很大的耕作土壤,利用温室试验,以小白菜为研究对象,通过外源添加铬(Cr),研究Cr从土壤向植物的运移,探索影响Cr生物有效性的主要土壤因素,并建立预测模型。结果表明,土壤总Cr含量、pH值和有机碳(OC)含量对... 详细信息

采集我国15个省份理化性质差异很大的耕作土壤,利用温室试验,以小白菜为研究对象,通过外源添加铬(Cr),研究Cr从土壤向植物的运移,探索影响Cr生物有效性的主要土壤因素,并建立预测模型。结果表明,土壤总Cr含量、pH值和有机碳(OC)含量对小白菜吸收Cr有显著影响。小白菜Cr含量与土壤Cr含量呈正相关,而与土壤pH值、OC含量呈负相关。相比于土壤总Cr含量的单因素回归分析,将土壤总Cr含量、pH值和有机碳(OC)含量纳入逐步多元线性回归(SMlR)后评价Cr生物有效性时,相关性更高,决定系数由0.861提高到0.927。Cr在酸性土壤中生物富集系数(BCF)较碱性土壤中更大。利用合并CK、Cr1、Cr2处理3个处理的数据(n=45)得到Freundlich预测方程(R2=0.927,RMSE为0.12),较单独使用CK处理数据(R2=0.572,RMSE为0.25,n=15)和使用Cr1和Cr2处理结合的数据(R2=0.745,RMSE为0.17,n=30)得出的方程,能更准确地评估Cr在土壤中生物有效性,试验结果可用于预测Cr从土壤到小白菜的转移。

关键词：铬转移特性小白菜控制因素预测模型

An overview on GNSS carrier-phase time transfer research

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Science China(Technological Sciences) 2020年第4期63卷 589-596页

作者： ZHANG Ming lü JinHu BAI ZhengDong JIANG ZhiQi CHEN BoBo The Key laboratory of Systems and Control Institute o f Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Institute of Geomatics of Tsinghua university Beijing 100084China Management and Department of Energy and Resources Engineering College of EngineeringPeking UniversityBeijing 100871China

Global navigation satellite system(GNSS)carrier phase observations are two orders of higher accuracy than pseudo-range observations,and they are less affected by multipath *** a result,the time transfer accuracy can reach 0.1 ns,and the frequency transfer stability can reach 1×10^-15 with carrier phase(CP)method,therefore CP method is considered the most accurate and promising time transfer *** focus of this paper is to present a comprehensive summary of CP method,with specific attention directed toward day-boundary clock jump,ambiguity resolution(AR),multi-system time transfer and real-time time ***-boundary clock jump is essentially caused by pseudo-range *** approaches were proposed to solve the problem,such as continuously processing strategy,sliding batch and bidirectional filtering methods which were compared in this ***,researches on AR in CP method were *** scholars attempted to fix the single-difference ambiguities to improve the time transfer result,however,owing to the uncalibrated phase delay(uPD)was not considered,the current studies on AR in CP method were still ***,because four GNSS systems could be used for time-transfer currently,which was helpful to increase the accuracy and reliability,the researches on multi-system time transfer were ***’s more,real-time time transfer attracted more attention nowadays,the preliminary research results were presented.

关键词： carrier phase(CP) time transfer day-boundary clock jump ambiguity resolution(AR) multi-system time transfer real-time time transfer

Generalized Weighted Morrey Estimates for Marcinkiewicz Integrals with Rough Kernel Associated with Schrodinger Operator and Their Commutators

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Chinese Annals of Mathematics,Series B 2020年第1期41卷 77-98页

作者： Ferit GuRBuZ Faculty of Education Department of Mathematics EducationHakkari UniversityHakkari 30000Turkey

let l =-△+V(x) be a Schrodinger operator, where △ is the laplacian on R^n,while nonnegative potential V(x) belonging to the reverse Holder class. The aim of this paper is to give generalized weighted Morrey estimates for the boundedness of Marcinkiewicz integrals with rough kernel associated with Schrodinger operator and their ***, the boundedness of the commutator operators formed by BMO functions and Marcinkiewicz integrals with rough kernel associated with Schrodinger operators is discussed on the generalized weighted Morrey spaces. As its special cases, the corresponding results of Marcinkiewicz integrals with rough kernel associated with Schrodinger operator and their commutators have been deduced, respectively. Also, Marcinkiewicz integral operators, rough Hardy-littlewood(H-l for short) maximal operators, Bochner-Riesz means and parametric Marcinkiewicz integral operators which satisfy the conditions of our main results can be considered as some examples.

关键词： Marcinkiewicz operator Rough kernel Schrodinger operator generalized weighted Morrey space Commutator BMO

温度效应对F-P腔光纤液位传感器系统的影响及自补偿

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光子学报 2007年第8期36卷 1471-1474页

作者：吕涛中国地质大学数理学院武汉430074

分析了温度效应对F-P腔光纤液位传感器系统的影响,提出相应的解决方案以实现对温度效应的自补偿.在26℃-28℃环境温度条件下,实验结果表明,在1 .87 m(水)量程内经过优化的传感系统参考光动态稳定性可达到0 .059 9 %,准确度误差为1 .122 ... 详细信息

分析了温度效应对F-P腔光纤液位传感器系统的影响,提出相应的解决方案以实现对温度效应的自补偿.在26℃-28℃环境温度条件下,实验结果表明,在1 .87 m(水)量程内经过优化的传感系统参考光动态稳定性可达到0 .059 9 %,准确度误差为1 .122 mm.自补偿措施对获得高准确度、长期稳定性的光纤液位传感器具有重要意义.

关键词：光纤传感器 F-P腔液位温度效应自补偿

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自成像魏格纳函数分析

光子学报 2007年第12期36卷 2325-2328页

作者：吕岑陕西科技大学电气与信息工程学院光电子系西安710021

在空域-频域空间,基于魏格纳变换和魏格纳分布函数,分析讨论了一维物体的自成像及其形成过程.从成像过程中各衍射频谱分量的光程差,给出了Talbot效应和Montgomery效应的统一解释.对于周期物的Talbot效应,得到了用杨氏双缝干涉解释自成... 详细信息

在空域-频域空间,基于魏格纳变换和魏格纳分布函数,分析讨论了一维物体的自成像及其形成过程.从成像过程中各衍射频谱分量的光程差,给出了Talbot效应和Montgomery效应的统一解释.对于周期物的Talbot效应,得到了用杨氏双缝干涉解释自成像现象的理论依据.周期物的自成像是物平面上间距为两倍周期、光程差为波长的整数平方倍的各衍射频谱分量同相相干迭加的结果.Montgomery效应是物平面上间距为抛物线关系、光程差为波长整数倍的各衍射频谱分量同相相干迭加的结果.

关键词：物理光学自成像 Talbot效应魏格纳函数 Montgomery效应

基于性能评价网状图的装载机发动机与液力变矩器匹配优化

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农业工程学报 2012年第1期28卷 50-54页

作者：常绿淮阴工学院交通工程学院淮安223003

为了解决装载机发动机与液力变矩器匹配性能评定指标较多,多项评价指标权重难以确定的问题,该文提出了基于性能评价网状图的发动机与液力变矩器匹配优化方法。装载机发动机与液力变矩器匹配性能评定指标有额定工况接近度、起动能度、经... 详细信息

为了解决装载机发动机与液力变矩器匹配性能评定指标较多,多项评价指标权重难以确定的问题,该文提出了基于性能评价网状图的发动机与液力变矩器匹配优化方法。装载机发动机与液力变矩器匹配性能评定指标有额定工况接近度、起动能度、经济区宽容度、功率输出系数、燃油消耗率系数等5项,分别定义和计算5项匹配性能指标,根据计算值的大小构建发动机与液力变矩器匹配性能网状评价图,以网状评价图面积最小为优化目标,构建目标函数,优化液力变矩器有效直径。原液力变矩器有效直径等于0.360 m;优化后的装载机液力变矩器有效直径等于0.350 m。优化后发动机与液力变矩器匹配性能提高了5.7%。基于性能网状图的优化方法提高了发动机与液力变矩器匹配性能。

关键词：柴油发动机液力变矩器优化装载机性能评价网状图

Chronic intestinal failure and short bowel syndrome in Crohn’s disease

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World Journal of Gastroenterology 2021年第24期27卷 3440-3465页

作者： Aysegül Aksan Karima Farrag Irina Blumenstein Oliver Schröder Axel.u Dignass Jürgen Stein Institute of Nutritional Sciences Justus-Liebig-UniversitätGiessen 35392Germany Department of Clinical Research Interdisziplinäres Crohn Colitis Centrum Rhein-MainFrankfurt am Main 60594Germany Department of Gastroenterology and Clinical Nutrition DGD Kliniken SachsenhausenTeaching Hospital of the JW Goethe UniversityFrankfurt am Main 60594Germany Department of Gastroenterology Hepatology and Clinical NutritionFirst Medical ClinicJW Goethe University HospitalFrankfurt am Main 60529Germany Department of MedicineⅠ Agaplesion Markus HospitalGoethe-UniversityFrankfurt am Main 60431Germany Institute of Pharmaceutical Chemistry JW Goethe University60438 Frankfurt am MainGermany

Chronic intestinal failure(CIF)is a rare but feared complication of Crohn’s *** on the remaining length of the small intestine,the affected intestinal segment,and the residual bowel function,CIF can result in a wide spectrum of symptoms,from single micronutrient malabsorption to complete intestinal *** of CIF has improved significantly in recent *** in home-based parenteral nutrition,in particular,have translated into increased survival and improved quality of ***,60%of patients are permanently reliant on parenteral *** results with new drugs such as teduglutide have added a new dimension to CIF *** outcomes of patients with CIF could be greatly improved by more effective prevention,understanding,and *** complex cases,the care of patients with CIF requires a multidisciplinary approach involving not only physicians but also dietitians and nurses to provide optimal intestinal rehabilitation,nutritional support,and an improved quality of ***,we summarize current literature on CIF and short bowel syndrome,encompassing epidemiology,pathophysiology,and advances in surgical and medical management,and elucidate advances in the understanding and therapy of CIF-related complications such as catheter-related bloodstream infections and intestinal failure-associated liver disease.

关键词： Chronic intestinal failure Short bowel syndrome Crohn's disease Inflammatory bowel disease Parenteral nutrition Intestinal failure-associated liver disease

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自相似网络流量的处理和分析

清华大学学报（自然科学版） 2008年第7期48卷 1186-1189页

作者：吕军清华大学信息网络工程研究中心北京100084

为了解决自相似模型难以进行自相似网络流量趋势预测的问题,提出时间序列分析中短时相关模型(自适应自回归模型)的方法用于流量数据的估计;同时为了提高预测精度,提出改进的最小平方格型(modified least squarelattice,MlSl)算法,使模... 详细信息

为了解决自相似模型难以进行自相似网络流量趋势预测的问题,提出时间序列分析中短时相关模型(自适应自回归模型)的方法用于流量数据的估计;同时为了提高预测精度,提出改进的最小平方格型(modified least squarelattice,MlSl)算法,使模型参数不断递推修正,收敛到最佳值。仿真试验结果验证了短时相关模型在网络流量预测应用中的可行性,实现了自相似网络流量的短期预测,该算法比最小平方(least square,lS)算法均方误差减少20%,具有收敛快、预测精度高的优点,而该算法的计算量减少一半。

关键词：计算机网络自相似特性流量模型短时相关模型