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| 1 | PID控制器参数的ITAE最佳设定公式显示文摘针对一类可以由带有纯时间延迟的一阶模型来近似描述的被控对象,运用参数寻优及曲线拟合等方法得到了一组基于被控对象特征参数的PID控制器最佳设定公式.仿真结果表明:应用该方法所设计的PID控制系统具有超调小、调整时间短、稳态误差小等特点,系统的动态特性较以往的经验公式有了大幅度提高.即使当对象纯滞后时间与时间常数的比值较大时仍然具有较好的控制效果.该方法简洁实用,不仅解决了常规PID控制系统参数整定不良的难题,同时也为进一步构造基于过程特征参数的自适应PID控制系统提供了有力的依据. | 张福波 王国栋 张殿华 刘相华 | 2005 | 东北大学学报(自然科学版)2005，26，8： | 22 |
| 2 | NECESSARY AND SUFFICIENT CONDITIONS FOR ABSOLUTE STABILITY OF LURIE INDIRECT CONTROL SYSTEMS显示文摘In this paper, we transform the Lurie indirect control systems into a nonlinear system with separating variables by a topological transformation and introduce a definition of absolute stability for partial variables. The necessary and sufficient conditions (NASC) for the absolute stability of Lurie indirect control systems are given and some sufficient conditions are obtained. | 廖晓昕 | 1989 | Science China Mathematics1989，32，9： | 11 |
| 3 | DYNAMIC BEHAVIOR ANALYSIS FOR LANDING-GEAR WITH DIFFERENT TYPES OF DUAL-CHAMBER SHOCK-STRUTS显示文摘In this paper three types of dual- chamber shock- struts are considered in dynamic analyses of landing-gear behavior during impact and taxi. Their dynamic characteristics are compared with each other according to calculation results, and some conclusions are presented.It is very helpful for selecting a suitable type of dual-chamber shock-strut in landing-gear design. | Nie Hong Qiao XinAircraft Engineering Department, Nanjing Aeronautical InstituteNanjing 210016, China Gao Zejun R&D Institute of Chendu Aircraft Corp.Chendu 610041, ChinaZhou Lanqin Landing Gear Manufa ctoryBox 43#, Yangxian, Shaanxi 723313, China | 1991 | Chinese Journal of Aeronautics1991，6，2： | 10 |
| 4 | Change-point estimation for censored regression model显示文摘In this paper, we consider the change-point estimation in the censored regression model assuming that there exists one change point. A nonparametric estimate of the change-point is proposed and is shown to be strongly consistent. Furthermore, its convergence rate is also obtained. | Zhan-feng WANG Yao-hua WU Lin-cheng ZHAO | 2007 | Science China Mathematics2007，50，1： | 9 |
| 5 | Six-long non-coding RNA signature predicts recurrence-free survival in hepatocellular carcinoma显示文摘BACKGROUND Recent evidence shows that long non-coding RNAs(lncRNAs) are closely related to hepatogenesis and a few aggressive features of hepatocellular carcinoma(HCC). Increasing studies demonstrate that lncRNAs are potential prognostic factors for HCC. Moreover, several studies reported the combination of lncRNAs for predicting the overall survival(OS) of HCC, but the results varied. Thus,more effort including more accurate statistical approaches is needed for exploring the prognostic value of lncRNAs in HCC.AIM To develop a robust lncRNA signature associated with HCC recurrence to improve prognosis prediction of HCC.METHODS Univariate COX regression analysis was performed to screen the lncRNAs significantly associated with recurrence-free survival(RFS) of HCC in GSE76427 for the least absolute shrinkage and selection operator(LASSO) modelling. The established lncRNA signature was validated and developed in The Cancer Genome Atlas(TCGA) series using Kaplan-Meier curves. The expression values of the identified lncRNAs were compared between the tumor and non-tumor tissues. Pathway enrichment of these lncRNAs was conducted based on the significantly co-expressed genes. A prognostic nomogram combining the lncRNA signature and clinical characteristics was constructed.RESULTS The lncRNA signature consisted of six lncRNAs: MSC-AS1, POLR2 J4, EIF3 J-AS1,SERHL, RMST, and PVT1. This risk model was significantly associated with the RFS of HCC in the TCGA cohort with a hazard ratio(HR) being 1.807(95%CI[confidence interval]: 1.329-2.457) and log-rank P-value being less than 0.001. The best candidates of the six-lncRNA signature were younger male patients with HBV infection in relatively early tumor-stage and better physical condition but with higher preoperative alpha-fetoprotein. All the lncRNAs were significantly upregulated in tumor samples compared to non-tumor samples(P < 0.05). The most significantly enriched pathways of the lncRNAs were TGF-β signaling pathway, cellular apoptosis-associated pathways, etc. The nomogram showed great utility of the lncRNA signature in HCC recurrence risk stratification.CONCLUSION We have constructed a six-lncRNA signature for prognosis prediction of HCC.This risk model provides new clinical evidence for the accurate diagnosis and targeted treatment of HCC. | Jing-Xian Gu Xing Zhang Run-Chen Miao Xiao-Hong Xiang Yu-Nong Fu Jing-Yao Zhang Chang Liu Kai Qu | 2019 | World Journal of Gastroenterology2019，25，2： | 9 |
| 6 | Development and application of ergodicity model with FRCM and FLAR for hydrological process显示文摘In this paper, a new ergodic property analysis model of hydrological process is proposed based on fuzzy-rough c-means clustering (FRCM), autocorrelogram, and fuzzy least absolute regression (FLAR). A precipitation time series (1951―2004) from Shanghai Hydrology Station is then analyzed with the model. The results show that the precipitation time series of April, May, June, and September has er-godic property. We conclude that in the long run, the precipitation of April, May, June, and September will not keep decreasing; it will converge to its mean value in some period. | WANG HongRui1, FENG QiLei2, LIN Xin3 & ZENG WenYi4 1 College of Water Science, Key Laboratory for Water and Sediment Sciences of the Ministry of Education, Beijing Normal University, Beijing 100875, China 2 School of Science, Beijing Institute of Education, Beijing 100011, China 3 School of Mathematical Sciences, Beijing Normal University, Beijing 100875, China 4 College of Information Science and Technology, Beijing Normal University, Beijing 100875, China | 2009 | Science China(Technological Sciences)2009，52，2： | 9 |
| 7 | Review of low timing jitter mode-locked fiber lasers and applications in dual-comb absolute distance measurement显示文摘Passively mode-locked fiber lasers emit femtosecond pulse trains with excellent short-term stability. The quantum-limited timing jitter of a free running femtosecond erbium-doped fiber laser working at room temperature is considerably below one femtosecond at high Fourier frequency. The ultrashort pulse train with ultralow timing jitter enables absolute time-of-flight measurements based on a dual-comb implementation, which is typically composed of a pair of optical frequency combs generated by femtosecond lasers. Dead-zone-free absolute distance measurement with sub-micrometer precision and kHz update rate has been routinely achieved with a dual-comb configuration, which is promising for a number of precision manufacturing applications, from large step-structure measurements prevalent in microelectronic profilometry to three coordinate measurements in large-scale aerospace manufacturing and shipbuilding. In this paper, we first review the sub-femtosecond precision timing jitter characterization methods and approaches for ultralow timing jitter mode-locked fiber laser design. Then, we provide an overview of the state-of-the-art dual-comb absolute ranging technology in terms of working principles, experimental implementations, and measurement precisions. Finally, we discuss the impact of quantum-limited timing jitter on the dual-comb ranging precision at a high update rate. The route to highprecision dual-comb range finder design based on ultralow jitter femtosecond fiber lasers is proposed. | Haosen Shi Youjian Song Runmin Li Yuepeng Li Hui Cao Haochen Tian Bowen Liu Lu Chai Minglie Hu | 2018 | Nanotechnology and Precision Engineering2018，1，4： | 9 |
| 8 | Dual-comb spectroscopy resolved three-degreeof-freedom sensing显示文摘Precise and fast determination of position and orientation, which is normally achieved by distance and angle measurements, has broad applications in academia and industry. We propose a dynamic three-degree-of-freedom measurement technique based on dual-comb interferometry and a self-designed grating-corner-cube(GCC) combined sensor. Benefiting from its unique combination of diffraction and reflection characteristics, the absolute distance, pitch, and yaw of the GCC sensor can be determined simultaneously by resolving the phase spectra of the corresponding diffracted beams. We experimentally demonstrate that the method exhibits a ranging precision(Allan deviation) of 13.7 nm and an angular precision of 0.088 arcsec, alongside a 1 ms reaction time. The proposed technique is capable of precise and fast measurement of distances and two-dimensional angles over long stand-off distances. A system with such an overall performance may be potentially applied to space missions,including in tight formation-flying satellites, for spacecraft rendezvous and docking, and for antenna measurement as well as the precise manufacture of components including lithography machines and aircraftmanufacturing devices. | SIYU ZHOU VUNAM LE SHILIN XIONG YUETANG YANG KAI NI QIAN ZHOU GUANHAO WU | 2021 | Photonics Research2021，9，2： | 8 |
| 9 | Computational dynamics of soft machines显示文摘Soft machine refers to a kind of mechanical system made of soft materials to complete sophisticated missions, such as handling a fragile object and crawling along a narrow tunnel corner, under low cost control and actuation.Hence, soft machines have raised great challenges to computational dynamics. In this review article, recent studies of the authors on the dynamic modeling, numerical simulation, and experimental validation of soft machines are summarized in the framework of multibody system dynamics. The dynamic modeling approaches are presented first for the geometric nonlinearities of coupled overall motions and large deformations of a soft component, the physical nonlinearities of a soft component made of hyperelastic or elastoplastic materials, and the frictional contacts/impacts of soft components,respectively. Then the computation approach is outlined for the dynamic simulation of soft machines governed by a set of differential-algebraic equations of very high dimensions,with an emphasis on the efficient computations of the nonlinear elastic force vector of finite elements. The validations of the proposed approaches are given via three case studies, including the locomotion of a soft quadrupedal robot,the spinning deployment of a solar sail of a spacecraft, and the deployment of a mesh reflector of a satellite antenna,as well as the corresponding experimental studies. Finally,some remarks are made for future studies. | Haiyan Hu Qiang Tian Cheng Liu | 2017 | Acta Mechanica Sinica2017，33，3： | 7 |
| 10 | 部分线性单指标模型的复合分位数回归及变量选择显示文摘本文提出复合最小化平均分位数损失估计方法 (composite minimizing average check loss estimation,CMACLE)用于实现部分线性单指标模型(partial linear single-index models,PLSIM)的复合分位数回归(composite quantile regression,CQR).首先基于高维核函数构造参数部分的复合分位数回归意义下的相合估计,在此相合估计的基础上,通过采用指标核函数进一步得到参数和非参数函数的可达最优收敛速度的估计,并建立所得估计的渐近正态性,比较PLSIM的CQR估计和最小平均方差估计(MAVE)的相对渐近效率.进一步地,本文提出CQR框架下PLSIM的变量选择方法,证明所提变量选择方法的oracle性质.随机模拟和实例分析验证了所提方法在有限样本时的表现,证实了所提方法的优良性. | 吕亚召 张日权 赵为华 刘吉彩 | 2014 | 中国科学:数学2014，44，12： | 7 |
| 11 | Participation in the absolute gravity comparison with a compact cold atom gravimeter显示文摘The first Asia-Pacific Comparison of Absolute Gravimeters(APMP.M.G-K1) was organized by the National Institute of Metrology(NIM) of China from December 21, 2015 to March 25, 2016 in Changping, Beijing. Our compact cold atom gravimeter(CCAG) was transported from Hangzhou to Beijing with a long distance of about1200 km to participate in this comparison. The CCAG is the only one, to the best of our knowledge, that is based on the principle of atom interferometry among all the instruments. Absolute gravity in the indicated three test sites has been measured as requested by the organizer. The sensitivity of our CCAG is estimated to be90 μGal∕Hz p, even when the measurements are carried out without any vibration isolation. Besides, the accuracy of this gravimeter has been evaluated to be about 19 μGal by considering the significant system errors.Our results show a good agreement with the given reference value. | 付志杰 王启宇 王兆英 吴彬 程冰 林强 | 2019 | Chinese Optics Letters2019，17，1： | 7 |
| 12 | Absolute monocyte and lymphocyte count prognostic score for patients with gastric cancer显示文摘AIM:To measure the prognostic significance of absolute monocyte count/absolute lymphocyte count prognostic score(AMLPS) in patients with gastric cancer.METHODS:We retrospectively examined the combination of absolute monocyte count(AMC) and absolute lymphocyte count(ALC) as prognostic variables in a cohort of 299 gastric cancer patients who underwent surgical resection between 2006 and 2013 and were followed at a single institution.Both AMC and ALC were dichotomized into two groups using cut-off points determined by receiving operator characteristic curve analysis.An AMLPS was generated,which stratified patients into three risk groups:low risk(both low AMC and high ALC),intermediate risk(either high AMC or low ALC),and high risk(both high AMC and low ALC).The primary objective of the study was to validate the impact of AMLPS on both disease-free survival(DFS) and overall survival(OS),and the second objective was to assess the AMLPS as an independent prognostic factor for survival in comparison with known prognostic factors.RESULTS:Using data from the entire cohort,the most discriminative cut-off values of AMC and ALC selected on the receiver operating characteristic curve were 672.4/μL and 1734/μL for DFS and OS.AMLPS risk groups included 158(52.8%) patients in the lowrisk,128(42.8%) in the intermediate-risk,and 13(4.3%) in the high-risk group.With a median followup of 37.2 mo(range:1.7-91.4 mo),five-year DFS rates in the low-,intermediate-,and high-risk groups were 83.4%,78.7%,and 19.8%,respectively.And fiveyear OS rates in the low-,intermediate-,and high-risk groups were 89.3%,81.1%,and 14.4%,respectively.On multivariate analysis performed with patient- and tumor-related factors,we identified AMLPS,age,and pathologic tumor-node-metastasis stage as the most valuable prognostic factors impacting DFS and OS.CONCLUSION:AMLPS identified patients with a poor DFS and OS,and it was independent of age,pathologic stage,and various inflammatory markers. | Wan Kyu Eo Da Wun Jeong Hye Jung Chang Kyu Yeoun Won Sung Il Choi Se Hyun Kim Sung Wook Chun Young Lim Oh Tae Hwa Lee Young Ok Kim Ki Hyung Kim Yong Il Ji Ari Kim Heung Yeol Kim | 2015 | World Journal of Gastroenterology2015，21，9： | 6 |
| 13 | Approximation by randomly weighting method in censored regression model显示文摘Censored regression ('Tobit') models have been in common use, and their linear hypothesis testings have been widely studied. However, the critical values of these tests are usually related to quantities of an unknown error distribution and estimators of nuisance parameters. In this paper, we propose a randomly weighting test statistic and take its conditional distribution as an approximation to null distribution of the test statistic. It is shown that, under both the null and local alternative hypotheses, conditionally asymptotic distribution of the randomly weighting test statistic is the same as the null distribution of the test statistic. Therefore, the critical values of the test statistic can be obtained by randomly weighting method without estimating the nuisance parameters. At the same time, we also achieve the weak consistency and asymptotic normality of the randomly weighting least absolute deviation estimate in censored regression model. Simulation studies illustrate that the per-formance of our proposed resampling test method is better than that of central chi-square distribution under the null hypothesis. | WANG ZhanFeng WU YaoHua ZHAO LinCheng | 2009 | Science China Mathematics2009，52，3： | 6 |
| 14 | Determination of the absolute ^(32)S/^(34)S ratio of IAEA-S-1 reference material and V-CDT sulfur isotope standard显示文摘The absolute 32S/34S ratios of IAEA-S-1 reference material and V-CDT standard are determined. For cross-checking, two sets of synthetic isotope mixtures are prepared from high purity 32S and 34S-enriched materials in different forms: the first set is prepared from BaSO4 whereas the second is prepared from Ag2S. The sulfur isotope analyses are done by using SF6 method with a MAT-251 EM mass spectrometer. The resulting 32S/34S ratio of IAEAS-1 reference material is 22.656 4±0. 006 0, and that of V-CDT is 22. 649 6±0. 006 0. | 丁悌平 白瑞梅 李延河 万德芳 邹晓秋 张青莲 | 1999 | Science China Earth Sciences1999，42，1： | 6 |
| 15 | Test of the uplift of Tibetan Plateau by FG5 absolute gravimeter at Lhasa station显示文摘The uplift of the Tibetan Plateau has been monitored by the FG5 absolute gravimeter, whose observing accuracy is as high as 1×10-8m/s2. The analysis of the gravity observation results at the Lhasa station in 1999 and 1993 shows that the gravity value has decreased by 12×10-8 m/s2, and it is confirmed that the Lhasa region is uplifting at a rate of 10 mm/a. | Weimin Zhang Yong Wang Houze Xu Chijun Zhang Xinghua Hao Ming Liu | 2001 | Chinese Science Bulletin2001，46，3： | 5 |
| 16 | A WiFi Fingerprint Based High-Adaptability Indoor Localization via Machine Learning显示文摘For received signal strength(RSS)fingerprint based indoor localization approaches,the localization accuracy is significantly influenced by the RSS variance,device heterogeneity and environment complexity.In this work,we present a high-adaptability indoor localization(HAIL)approach,which leverages the advantages of both relative RSS values and absolute RSS values to achieve robustness and accuracy.Particularly,a backpropagation neural network(BPNN)is devised in HAIL to measure the fingerprints similarities based on absolute RSS values.With this aid,the characteristics of the applied area could be specially learned such that HAIL could be adaptive to different environments.The experiments demonstrate that HAIL achieves high localization accuracy with the average localization error of 0.87 m in the typical environments.Moreover,HAIL has the minimum amount of large errors and decreases the average localization error by about 30%~50%compared with the existing approaches. | Jianzhe Xue Junyu Liu Min Sheng Yan Shi Jiandong Li | 2020 | China Communications2020，17，7： | 5 |
| 17 | The existence theorem of absolute equilibrium about games on connected graph with state payoff vector显示文摘By introducing state payoff vector to every state node on the connected graph in this paper,dynamic game is researched on finite graphs.The concept of simple strategy about games on graph defined by Berge is introduced to prove the existence theorem of absolute equilibrium about games on the connected graph with state payoff vector.The complete algorithm and an example in the three-dimensional connected mesh-like graph are given in this paper. | GAO HongWei,YANG HuiJing,WANG GuiXi & YU Kun College of Mathematics,Qingdao University,Qingdao 266071,China | 2010 | Science China Mathematics2010，53，6： | 5 |
| 18 | A New Flexible Multibody Dynamics Analysis Methodology of Deployable Structures with Scissor-Like Elements显示文摘There are vast constraint equations in conventional dynamics analysis of deployable structures,which lead to differential-algebraic equations(DAEs)solved hard.To reduce the difficulty of solving and the amount of equations,a new flexible multibody dynamics analysis methodology of deployable structures with scissor-like elements(SLEs)is presented.Firstly,a precise model of a flexible bar of SLE is established by the higher order shear deformable beam element based on the absolute nodal coordinate formulation(ANCF),and the master/slave freedom method is used to obtain the dynamics equations of SLEs without constraint equations.Secondly,according to features of deployable structures,the specification matrix method(SMM)is proposed to eliminate the constraint equations among SLEs in the frame of ANCF.With this method,the inner and the boundary nodal coordinates of element characteristic matrices can be separated simply and efficiently,especially on condition that there are vast nodal coordinates.So the element characteristic matrices can be added end to end circularly.Thus,the dynamic model of deployable structure reduces dimension and can be assembled without any constraint equation.Next,a new iteration procedure for the generalized-a algorithm is presented to solve the ordinary differential equations(ODEs)of deployable structure.Finally,the proposed methodology is used to analyze the flexible multi-body dynamics of a planar linear array deployable structure based on three scissor-like elements.The simulation results show that flexibility has a significant influence on the deployment motion of the deployable structure.The proposed methodology indeed reduce the difficulty of solving and the amount of equations by eliminating redundant degrees of freedom and the constraint equations in scissor-like elements and among scissor-like elements. | Qi’an Peng Sanmin Wang Changjian Zhi Bo Li | 2019 | Chinese Journal of Mechanical Engineering2019，32，5： | 5 |
| 19 | Impact of Surface Potential Vorticity Density Forcing over the Tibetan Plateau on the South China Extreme Precipitation in January 2008. Part Ⅰ:Data Analysis显示文摘The external source/sink of potential vorticity (PV) is the original driving force for the atmospheric circulation. The relationship between surface PV generation and surface PV density forcing is discussed in detail in this paper. Moreover, a case study of the extreme winter freezing rain/snow storm over South China in January 2008 is performed, and the surface PV density forcing over the eastern flank of the Tibetan Plateau (TP) has been found to significantly affect the precipitation over South China in this case. The TP generated PV propagated eastward in the middle troposphere. The associated zonal advection of positive absolute vorticity resulted in the increasing of cyclo-nic relative vorticity in the downstream region of the TP. Ascending air and convergence in the lower troposphere developed, which gave rise to the development of the southerly wind. This favored the increasing of negative meridio-nal absolute vorticity advection in the lower troposphere, which provided a large-scale circulation background conducive to ascending motion such that the absolute vorticity advection increased with height. Consequently, the ascending air further strengthened the southerly wind and the vertical gradient of absolute vorticity advection between the lower and middle troposphere in turn. Under such a situation, the enhanced ascending, together with the moist air transported by the southerly wind, formed the extreme winter precipitation in January 2008 over South China. | Tingting MA Guoxiong WU Yimin LIU Zhihong JIANG Jiahui YU | 2019 | Journal of Meteorological Research2019，33，3： | 4 |
| 20 | On Absolute Stability for a Class of Nonlinear Control Systems With Delay显示文摘1 Introduction It is known that the stability of control systems is very important. So far, the absolute stability of nonlinear ordinary control systems has been widely studied and many outstanding results have been obtained. However, for the absolute stability of nonlinear control systems with delay, seldom results have been reported. Since the nonlinear control systems with delay are defined on the function space, the absolute stability of it is more difficult and complex than that of nonlinear ordinary control systems. On the other hand, almost all the closed loop control systems are affected by delay. It must be interesting to study the absolute stability of nonlinear control systems with delay. In | 王联 张毅 章毅 | 1993 | Chinese Science Bulletin1993，38，20： | 4 |
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