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Decomposition Based Fuzzy Model Predictive Control Approaches for Interconnected Nonlinear Systems
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作者 Latifa Dalhoumi Mohamed Chtourou Mohamed Djemel 《国际自动化与计算杂志:英文版》 EI CSCD 2019年第3期369-388,共20页
This paper proposes fuzzy model predictive control(FMPC)strategies for nonlinear interconnected systems based mainly on a system decomposition approach.First,the Takagi-Sugeno(TS)fuzzy model is formulated in such a wa... This paper proposes fuzzy model predictive control(FMPC)strategies for nonlinear interconnected systems based mainly on a system decomposition approach.First,the Takagi-Sugeno(TS)fuzzy model is formulated in such a way to describe the behavior of the nonlinear system.Based on that description,a fuzzy model predictive control is determined.The system under consideration is decomposed into several subsystems.For each subsystem,the main idea consists of the decomposition of the control action into two parts:The decentralized part contains the parameters of the subsystem and the centralized part contains the elements of other subsystems.According to such decomposition,two strategies are defined aiming to circumvent the problems caused by interconnection bet ween subsystems.The feasibility and efficiency of the proposed method are illustrated through numerical examples. 展开更多
关键词 MODEL PREDICTIVE CONTROL centralized CONTROL decentralized CONTROL Takagi-Sugeno(TS)fuzzy models·interconnected nonlinear systems FUZZY MODEL PREDICTIVE CONTROL parallel distributed compensation
Rail pressure controller design of GDI basing on predictive functional control
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作者 Zhiming ZHANG Lei XIE Hongye SU 《控制理论与技术:英文版》 EI CSCD 2019年第2期176-182,共7页
Gasoline direct injection(GDI)is a pivotal technique for a highly efficient engine.However,how to maintain a stable rail pressure which offers good fuel economy and low emissions,is still a challengeable work.In this ... Gasoline direct injection(GDI)is a pivotal technique for a highly efficient engine.However,how to maintain a stable rail pressure which offers good fuel economy and low emissions,is still a challengeable work.In this paper,a rail pressure controller is designed basing on predictive functional control(PFC),a model predictive control(MPC)method,to surmount the nonlinearity and disc on tinuity brought by the common rail pressure system(CRPS).A control-oriented piecewise linear model is prese nted to simplify the CRPS.The simulation results on a benchmark show that rail pressure tracks the setpoint accurately even with some perturbations.Profiting from the conciseness of PFC algorithm,the controller can compute the online solution in a short time,which makes it possible to realize the strategy on a fast response system. 展开更多
关键词 RAIL pressure CONTROL model based PREDICTIVE CONTROL PREDICTIVE FUNCTIONAL CONTROL
Adaptive and Predictive Control Strategies for Wind Turbine Systems: A Survey 预览
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作者 Magdi S.Mahmoud Mojeed O.Oyedeji 《自动化学报:英文版》 CSCD 2019年第2期364-378,共15页
The wind turbine(WT) is a renewable energy conversion device for transformation of kinetic energy from the wind to mechanical energy for subsequent use in different forms.This paper focuses on wind turbine control des... The wind turbine(WT) is a renewable energy conversion device for transformation of kinetic energy from the wind to mechanical energy for subsequent use in different forms.This paper focuses on wind turbine control design strategies.The content is divided into the following parts: 1) An overview of the recent advances that have been made in the application of adaptive and model predictive control strategies for wind turbines. 2) Summarizes some important aspects of modeling of wind turbines for control studies. 3) Provides an outlook on the application of adaptive model predictive control for uncertain systems to stimulate new research interests for wind turbine systems. We provide an overall picture of the research results with evaluation of the merits/demerits. 展开更多
关键词 ADAPTIVE CONTROL model PREDICTIVE CONTROL WIND turbine(WT)
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Low platelet count: Predictor of death and graft loss after liver transplantation 预览
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作者 Pedro Beltrame Santiago Rodriguez Ajacio Bandeira de Mello Brandao 《世界肝病学杂志:英文版(电子版)》 2019年第1期99-108,共10页
BACKGROUND The impact of platelets on liver transplantation (LT) is well recognized, but not completely understood. Platelets exert dichotomous effects on the graft and on the patient. On the one hand, they are essent... BACKGROUND The impact of platelets on liver transplantation (LT) is well recognized, but not completely understood. Platelets exert dichotomous effects on the graft and on the patient. On the one hand, they are essential for primary hemostasis and tissue repair and regeneration. On the other hand, they support ischemia/reperfusion injury and inflammatory processes. Recent evidence has shown a new role for platelet count (PC) in predicting outcomes after LT. AIM To evaluate if low PC is a predictor of short- and long-term outcomes after LT. METHODS Four hundred and eighty consecutive LT patients were retrospectively assessed. PC from the preoperative to the seventh postoperative day (POD) were considered. C-statistic analysis defined the ideal cutoff point for PC. Cox regression was performed to check whether low PC was a predictor of death, retransplantation or primary changes in graft function within one year after LT. RESULTS The highest median PC was 86 × 10^9/L [interquartile range (IQR)= 65–100 × 10^9/L] on seventh POD, and the lowest was 51 × 10^9/L (IQR = 38–71 × 10^9/L) on third POD. The C-statistic defined a PC < 70 × 10^9/L on fifth POD as the ideal cutoff point for predicting death and retransplantation. In the multivariate analysis, platelets < 70 × 10^9/L on 5POD was an independent risk factor for death at 12 mo after LT [hazard ratio (HR)= 2.01; 95% confidence interval (CI) 1.06-3.79; P = 0.031]. In the Cox regression, patients with PC < 70 × 10^9/L on 5POD had worse graft survival rates up to one year after LT (HR = 2.76; 95%CI 1.52-4.99; P = 0.001). CONCLUSION PC < 70 × 10^9/L on 5POD is an independent predictor of death in the first year after LT. These results are in agreement with other studies that indicate that low PC after LT is associated with negative outcomes. 展开更多
关键词 PREDICTIVE factors Prognosis PLATELET COUNT Liver transplantation GRAFT survival MORTALITY
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The role of tumor size,ultrasonographic findings,and serum tumor markers in predicting the likelihood of malignant testicular histology
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作者 Gang Song Geng-Yan Xiong +6 位作者 Yu Fan Cong Huang Yong-Ming Kang Guang-Jie Ji Jin-Chao Chen Zhong-Cheng Xin Li-Qun Zhou 《亚洲男性学杂志:英文版》 SCIE CAS CSCD 2019年第2期196-200,共5页
The clin ical predictive factors for maligna nt testicular histology remain unclear because of the low prevale nee.Therefore,the aim of this study was to investigate predictors of malignant histology for testicular ma... The clin ical predictive factors for maligna nt testicular histology remain unclear because of the low prevale nee.Therefore,the aim of this study was to investigate predictors of malignant histology for testicular masses and decide more testis-sparing surgeries before surgery.This retrospective study enrolled 325 consecutive testicular mass patients who underwent radical orchiectomy(310/325)or testicular preserving surgery(15/325)from January 2001 to June 2016.The clinicopathological factors,including tumor diameter,cryptorchidism history,ultraso und fin dings,serum alpha-fetoprotein,and human chorio nic gonadotropin(HCG)levels,were collected retrospectively for statistical an alysis.A predictive no mogram was also gen erated to evaluate the qua ntitative probability.Among all patients,247(76.0%)were diagnosed with a malignant testicular tumor and 78(24.0%)with benign histology.Larger tumor diameter(percm increased,hazard ratio[HR]=1.284,P=0.036),lower ultrasound echo(HR=3.191,P=0.001),higher ultrasound blood flow(HR=3.320,P<0.001),and abnormal blood HCG(HR=10.550,P<0.001)were significant predictive factors for malignant disease in all testicular mass patients?The nomogram generated was well calibrated for all predicti ons of malig nant probability,and the accuracy of the model no mogram measured by HarrelTs C statistic(C-in dex)was 0.92.According to our data,the proportion of patients who underwent radical orchiectomy for benign tumors(24.0%)was much larger tha n gen erally believed(10.0%).Our results in dicated that the diameter,ultras onic echo,ultras onic blood flow,and serum HCG levels could predict the malignancy in testicular mass patients. 展开更多
关键词 MALIGNANT LIKELIHOOD predictive model TESTICULAR tumor UROLOGICAL ONCOLOGY
An integrated method of selecting environmental covariates for predictive soil depth mapping 预览
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作者 LU Yuan-yuan LIU Feng +2 位作者 ZHAO Yu-guo SONG Xiao-dong ZHANG Gan-lin 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第2期301-315,共15页
Environmental covariates are the basis of predictive soil mapping.Their selection determines the performance of soil mapping to a great extent,especially in cases where the number of soil samples is limited but soil s... Environmental covariates are the basis of predictive soil mapping.Their selection determines the performance of soil mapping to a great extent,especially in cases where the number of soil samples is limited but soil spatial heterogeneity is high.In this study,we proposed an integrated method to select environmental covariates for predictive soil depth mapping.First,candidate variables that may influence the development of soil depth were selected based on pedogenetic knowledge.Second,three conventional methods(Pearson correlation analysis(PsCA),generalized additive models(GAMs),and Random Forest(RF))were used to generate optimal combinations of environmental covariates.Finally,three optimal combinations were integrated to produce a final combination based on the importance and occurrence frequency of each environmental covariate.We tested this method for soil depth mapping in the upper reaches of the Heihe River Basin in Northwest China.A total of 129 soil sampling sites were collected using a representative sampling strategy,and RF and support vector machine(SVM)models were used to map soil depth.The results showed that compared to the set of environmental covariates selected by the three conventional selection methods,the set of environmental covariates selected by the proposed method achieved higher mapping accuracy.The combination from the proposed method obtained a root mean square error(RMSE)of 11.88 cm,which was 2.25–7.64 cm lower than the other methods,and an R~2 value of 0.76,which was 0.08–0.26 higher than the other methods.The results suggest that our method can be used as an alternative to the conventional methods for soil depth mapping and may also be effective for mapping other soil properties. 展开更多
关键词 ENVIRONMENTAL COVARIATE selection integrated method PREDICTIVE SOIL MAPPING SOIL depth
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Predictive analysis for race detection in software-defined networks
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作者 Gongzheng LU Lei XU +1 位作者 Yibiao YANG Baowen XU 《中国科学:信息科学(英文版)》 SCIE EI CSCD 2019年第6期34-53,共20页
Race condition remains one kind of the most common concurrency bugs in software-defined networks(SDNs). The race conditions can be exploited to lead to security and reliability risks. However,the race conditions are n... Race condition remains one kind of the most common concurrency bugs in software-defined networks(SDNs). The race conditions can be exploited to lead to security and reliability risks. However,the race conditions are notoriously difficult to detect. The existing race detectors for SDNs have limited detection capability. They can only detect the races in the original traces(observed traces) and cause false negatives. In this study, we present a predictive analysis framework called SDN-predict for race detection in SDNs. By encoding the order between the specified network events in SDNs as constraint, we formulate race detection as a constraint solving problem. In addition to detecting the races in the original trace, our framework can also detect the races in the feasible traces got from reordering the events in the original trace while satisfying the consistency requirements of trace. Moreover, we formally prove that our predictive analysis framework is sound and can achieve the maximal possible detection capability for any sound dynamic race detector with respect to the same trace. We evaluate our framework on a set of traces collected from three SDN controllers(POX, Floodlight, ONOS), running 5 representative applications including reactive and proactive applications in large networks, on three different network topologies. These experiments show that our framework has higher race detection capability than exisiting SDN race detector-SDNRacer, and detects more 1173 races. These 1173 races were previously undetected and confirmed by checking the race graphs. 展开更多
关键词 CONSTRAINT SOLVING PREDICTIVE analysis RACE detection software-defined NETWORKS
Eosinopenia is a predictive factor for the severity of acute ischemic stroke 预览
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作者 Hui-Min Zhao Wen-Qian Qin +1 位作者 Pei-Ji Wang Zhong-Min Wen 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第10期1772-1779,共8页
Previous data have revealed an association between eosinopenia and mortality of acute ischemic stroke.However,the relationship of eosinopenia with infarct volume,infection rate,and poor outcome of acute ischemic strok... Previous data have revealed an association between eosinopenia and mortality of acute ischemic stroke.However,the relationship of eosinopenia with infarct volume,infection rate,and poor outcome of acute ischemic stroke is still unknown.The retrospective study included 421 patients(273 males,65%;mean age,68.0± 13.0 years)with first acute ischemic stroke who were hospitalized in the Second Affiliated Hospital of Soochow University,China,from January 2017 to February 2018.Laboratory data,neuroimaging results,and modified Rankin Scale scores were collected.Patients were divided into four groups according to their eosinophil percentage level(<0.4%,0.4-1.1%,1 1-2.3%,≥2.3%).Spearman’s correlation analysis showed that the percentage of eosinophils was negatively correlated with infarct volume(rs=-0.514,P<0.001).Receiver operating characteristic analysis demonstrated that eosinopenia predicted a large infarct volume more accurately than neutrophilia;the area under curve was 0.906 and 0.876,respectively;a large infarct was considered as that with a diameter larger than 3 cm and involving more than two major arterial blood supply areas.Logistic regression analysis revealed that eosinophil percentage was an independent risk factor for acute ischemic stroke(P=0.002).Moreover,eosinophil percentage was significantly associated with large infarct volume,high infection rate(pulmonary and urinary tract infections),and poor outcome(modified Rankin Scale score>3)after adjusting for potential confounding factors(P-trend<0.001).These findings suggest that eosinopenia has the potential to predict the severity of acute ischemic stroke.This study was approved by the Ethics Committee of the Second Affiliated Hospital of Soochow University,China(approval number:K10)on November 10,2015. 展开更多
关键词 nerve REGENERATION eosinopenia EOSINOPHIL ISCHEMIA stroke INFARCT volume infection clinical outcome neutrophilia risk factors PREDICTIVE factor neural REGENERATION
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Learning Hand Latent Features for Unsupervised 3D Hand Pose Estimation 预览
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作者 Jamal Banzi Isack Bulugu Zhongfu Ye 《自主智能(英文)》 2019年第1期1-10,共10页
Recent hand pose estimation methods require large numbers of annotated training data to extract the dynamic information from a hand representation.Nevertheless,precise and dense annotation on the real data is difficul... Recent hand pose estimation methods require large numbers of annotated training data to extract the dynamic information from a hand representation.Nevertheless,precise and dense annotation on the real data is difficult to come by and the amount of information passed to the training algorithm is significantly higher.This paper presents an approach to developing a hand pose estimation system which can accurately regress a 3D pose in an unsupervised manner.The whole process is performed in three stages.Firstly,the hand is modelled by a novel latent tree dependency model (LTDM) which transforms internal joints location to an explicit representation.Secondly,we perform predictive coding of image sequences of hand poses in order to capture latent features underlying a given image without supervision.A mapping is then performed between an image depth and a generated representation.Thirdly,the hand joints are regressed using convolutional neural networks to finally estimate the latent pose given some depth map.Finally,an unsupervised error term which is a part of the recurrent architecture ensures smooth estimation of the final pose.To demonstrate the performance of the proposed system,a complete experiment was conducted on three challenging public datasets,ICVL,MSRA,and NYU.The empirical results show the significant performance of our method which is comparable or better than the state-of-the-art approaches. 展开更多
关键词 HAND Pose Estimation Convolutional NEURAL NETWORKS Recurrent NEURAL NETWORKS HUMAN-MACHINE Interaction Predictive Coding UNSUPERVISED LEARNING
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Control of the common rail pressure in gasoline engines through an extended state observer based MPC
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作者 Chao WU Kang SONG Hui XIE 《控制理论与技术:英文版》 EI CSCD 2019年第2期156-166,共11页
In this paper,a model predictive control(MPC)solution,assisted by extended state observer(ESO),is proposed for the common rail pressure control in gasoline engines.The rail pressure dynamic,nonlinear with large uncert... In this paper,a model predictive control(MPC)solution,assisted by extended state observer(ESO),is proposed for the common rail pressure control in gasoline engines.The rail pressure dynamic,nonlinear with large uncertainty,is modeled as a simple first order system.The discrepancy of the model from the real plant is lumped as"total disturbance",to be estimated in real-time by ESO and the n mitigated in the nonlin ear MPC,assuming the total disturbance does not change in the prediction horiz on.The non linear MPC problem is solved using the Newton/generalized minimum residual(GMRES)algorithm.The proposed ESO-MPC solution,is compared with the conventional proportional-integral-differential(PID)controller,based on the high-fidelity model provided in the benchmark problem in IFAC-E-CoSM.Results show the following benefits from using ESO-MPC relative to PID(benchmark):1)the disturbance rejection capability to fuel inject pulse step is improved by 12%in terms of recovery time;2)the transient response of rail pressure is improved by 5%in terms of the integrated absolute tracking error;and 3)the robustness is improved without n eed for gain scheduling,which is required in PID.Additionally,in creasing the ban dwidth of ESO allows reducing the complexity of the model implemented in MPC,while maintaining the disturbance rejection performance at the cost of high noise-sensitivity.Therefore,the ESO-MPC combination offers a simpler and more practical solution for common rail pressure control,relative to the standard MPC,which is consistent with the findings in simulation. 展开更多
关键词 RAIL pressure CONTROL fuel system CONTROL model PREDICTIVE CONTROL extended state OBSERVER active DISTURBANCE REJECTION CONTROL
A two-level hierarchical discrete-device control method for power networks with integrated wind farms 预览
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作者 Fengda XU Qinglai GUO +2 位作者 Hongbin SUN Boming ZHANG Lin JIA 《现代电力系统与清洁能源学报(英文)》 CSCD 2019年第1期88-98,共11页
Power systems depend on discrete devices, such as shunt capacitors/reactors and on-load tap changers, for their long-term reliability.In transmission systems that contain large wind farms, we must take into account th... Power systems depend on discrete devices, such as shunt capacitors/reactors and on-load tap changers, for their long-term reliability.In transmission systems that contain large wind farms, we must take into account the uncertainties in wind power generation when deciding when to operate these devices.In this paper, we describe a method to schedule the operation of these devices over the course of the following day.These schedules are designed to minimize wind-power generation curtailment, bus voltage violations, and dynamic reactive-power deviations,even under the worst possible conditions.Daily voltagecontrol decisions are initiated every 15 min using a dynamic optimization algorithm that predicts the state of the system over the next 4-hour period.For this, forecasts updated in real-time are employed, because they are more precise than forecasts for the day ahead.Day-ahead schedules are calculated using a two-stage robust mixedinteger optimization algorithm.The proposed control strategies were tested on a Chinese power network with wind power sources;the control performance was also validated numerically. 展开更多
关键词 Automatic voltage CONTROL Model PREDICTIVE CONTROL On-load tap CHANGER SHUNT capacitor/reactor TWO-STAGE robust optimization Wind-power integration
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Economical Optimization of Grid Power Factor Using Predictive Data 预览
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作者 Chaojiong Huang Jason Gu +2 位作者 Haiying Liu Yuansheng Lu Jun Luo 《自动化学报:英文版》 CSCD 2019年第1期258-267,共10页
We present an electrical grid optimization method for economical benefit. After simplifying an IEEE feeder diagram, we build a compact smart grid system including a photovoltaic-inverter system, a shunt capacitor, an ... We present an electrical grid optimization method for economical benefit. After simplifying an IEEE feeder diagram, we build a compact smart grid system including a photovoltaic-inverter system, a shunt capacitor, an on-load tapchanger(OLTC) and transmission lines. The system power factor(PF) regulation and reactive power dispatching are indispensable to improve power quality. Our control method uses predictive weather and load data to decide engaging or tripping the shunt capacitor, or reactive power injection by the photovoltaic-inverter system, ultimately to keep the system PF in a good range. From the perspective of economics, the economical model is considered as a decision maker in our predictive data control method.Capacitor-only control strategy is a common photovoltaic(PV)regulation method, which is treated as a baseline case. Simulations with GridLAB-D on profiled loads and residential loads have been carried out. The comparison results with baseline control strategy and our predictive data control method show the appreciable economical benefit of our method. 展开更多
关键词 GRID OPTIMIZATION GridLAB-D INVERTER power factor PREDICTIVE DATA control SHUNT capacitor
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A predictive deconvolution method for non-white-noise refl ectivity 预览
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作者 Wang De-Ying Kong Xue +3 位作者 Dong Lie-Qian Chen Li-Hua Wang Yong-Jun Wang Xiao-Chen 《应用地球物理:英文版》 SCIE CSCD 2019年第1期101-115,共15页
Conventional predictive deconvolution assumes that the reflection coefficients of the earth conform to an uncorrelated white noise sequence. The Wiener-Hopf (WH) equation is constructed to solve the filter and elimina... Conventional predictive deconvolution assumes that the reflection coefficients of the earth conform to an uncorrelated white noise sequence. The Wiener-Hopf (WH) equation is constructed to solve the filter and eliminate the correlated components of the seismic records, attenuate multiples, and improve seismic resolution. However, in practice, the primary refl ectivity series of fi eld data rarely satisfy the white noise sequence assumption, with the result that the correlated components of the primary reflectivity series are also eliminated by traditional deconvolution. This results in signal distortion. To solve this problem, we have proposed an improved method for deconvolution. First, we estimated the wavelet correlation from seismic records using the spectrum-modeling method. Second, this wavelet autocorrelation was used to construct a new autocorrelation function which contains the correlated components caused by the existence of multiples and avoids the correlated components of the primary reflectivity series. Finally, the new autocorrelation function was brought into the WH equation, and the predictive fi lter operator was calculated for deconvolution. In this paper, we have applied this new method to simulated and field data processing, and we have compared its performance with that of traditional predictive deconvolution. Our results show that the new method can adapt to non-white refl ectivity series without changing the statistical characteristics of the primary reflection coefficient series. Compared with traditional predictive deconvolution, the new method reduces processing noise and improves fidelity, all while maintaining the ability to attenuate multiples and enhance seismic resolution. 展开更多
关键词 Non-white reflectivity series predictive DECONVOLUTION spectrum-modeling multiples resolution AUTOCORRELATION
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晚期卵巢癌患者卵巢癌组织中免疫细胞表达水平与新辅助化疗敏感性的关系 预览
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作者 李贺群 徐晖 +3 位作者 严波 侯莹 黄大福 张雷 《癌症进展》 2019年第3期344-347,365共5页
目的探讨晚期卵巢癌患者肿瘤局部CD8^+细胞毒性T细胞(TLC)和叉头/翼状螺旋转录因子(FOXP3^+)调节性细胞(Treg)表达与新辅助化疗敏感性的关系。方法回顾性分析82例接受新辅助化疗的晚期卵巢癌患者的临床资料。采用免疫组织化学染色检测CD... 目的探讨晚期卵巢癌患者肿瘤局部CD8^+细胞毒性T细胞(TLC)和叉头/翼状螺旋转录因子(FOXP3^+)调节性细胞(Treg)表达与新辅助化疗敏感性的关系。方法回顾性分析82例接受新辅助化疗的晚期卵巢癌患者的临床资料。采用免疫组织化学染色检测CD8^+TLC和FOXP3^+Treg在卵巢癌组织和癌旁组织中的表达情况,晚期卵巢癌患者客观缓解率(ORR)的影响因素采用Logistic回归分析。依据是否达到病理学完全缓解分为缓解组(n=15)和未缓解组(n=67),比较两组患者CD8^+TLC和FOXP3^+Treg的表达水平。结果新辅助化疗前和化疗后,癌旁组织中CD8^+CTL和FOXP3^+Treg表达水平均明显高于卵巢癌组织(P﹤0.01);且FOXP3^+Treg在卵巢癌组织和癌旁组织中的表达水平均明显低于化疗前(P﹤0.01),但CD8^+CTL在卵巢癌组织和癌旁组织中的表达水平与化疗前比较,差异均无统计学意义(P﹥0.05)。新辅助化疗后,61例(74.39%)患者达到客观缓解,15例(18.29%)患者达到病理学完全缓解。Logistic回归分析结果显示,癌旁组织CD8^+CTL高表达、卵巢癌组织FOXP3^+Treg低表达、国际妇产科联盟(FIGO)分期为Ⅳ期是ORR的影响因素。卵巢癌组织和癌旁组织中,未缓解组患者FOXP3^+Treg表达水平高于缓解组患者(P﹤0.05);但缓解组和未缓解组患者CD8^+CTL表达水平比较,差异均无统计学意义(P﹥0.05)。结论晚期卵巢癌患者肿瘤局部FOXP3^+Treg细胞浸润状态可作为新辅助化疗敏感性的有效预测指标。 展开更多
关键词 晚期卵巢癌 新辅助化疗 肿瘤浸润淋巴细胞 预测价值
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Vlean platelet volume might.be an effective ndicator of arterial erectile dysfunction
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作者 Xue-Sheng Wang Li-Qiang Guo +7 位作者 Zhi-Ying Xiao Yong Guan Jian-Ye Zhang Ming Li Zhen Ma Zhi-He Xu Guo-Mei Ye Ming-Zhen Yuan 《亚洲男性学杂志:英文版》 SCIE CAS CSCD 2019年第1期62-66,共5页
The aim of our study was to investigate the role of platelet parameters including mean platelet volume (MPV)and platelet count (PC) in the pathogenesis of penile arteriogenic erectile dysfunction (ED)and to evaluate t... The aim of our study was to investigate the role of platelet parameters including mean platelet volume (MPV)and platelet count (PC) in the pathogenesis of penile arteriogenic erectile dysfunction (ED)and to evaluate the association between the platelet parameters and arteriogenic ED.There were 244 patients with ED (based on the International Index of Erectile Function [IIEF]-5≤21)and 60 healthy controls (IIEF-5 >21)enrolled.All participants were asked to undergo a laboratory examination,and penile vascular function was evaluated using penile color Doppler ultrasonography (pDUS).Among these ED patients,24 patients with no abnormality on nocturnal penile tumescence (NPT)and 84 with normal vasculature or mixed vascular abnormalities were excluded.The other patients were classified into three groups as follows:control (n =60),arteriogenic ED (n =99),and venous leakage (n =37) groups.MPV and PC were significantly higher in the arteriogenic ED group compared with the venous and control groups (P<0.05). Receiver operating characteristic curve analysis revealed that the area under the curve for MPV to predict arteriogenic ED was 0.707. MPV≥9.65 fl was recognized as a cut-off value for potential arteriogenic ED (sensitivity:47.5%;specificity:91.7%).A significant inverse correlation was detected between MPV and lO-min peak systolic velocity (PSV)(r =-0.34;P <0.001)in the arteriogenic ED group.These findings suggest that the MPV might be a powerful indicator to predict and diagnose arteriogenic ED,and MPV may be a marker for ED when using pDUS. 展开更多
关键词 ARTERIAL erectile DYSFUNCTION color Doppler ULTRASONOGRAPHY mean PLATELET volume peak SYSTOLIC velocity PREDICTIVE indicator
Semi-Active Predictive Control of Isolated Bridge Based on Magnetorheological Elastomer Bearing
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作者 李锐 周梦娇 +1 位作者 吴孟娟 唐晓铭 《上海交通大学学报:英文版》 EI 2019年第1期64-70,共7页
Time-delay of magnetorheological elastomer bearing(MRB) can bring structural response menace to bridges. This paper investigates a bridge pier-bearing semi-active-coupling control method based on model predictive cont... Time-delay of magnetorheological elastomer bearing(MRB) can bring structural response menace to bridges. This paper investigates a bridge pier-bearing semi-active-coupling control method based on model predictive control(MPC). The presented strategy takes the structure prediction model to predict the state responses of the controlled plant in a period of future time. Then, the control law can be determined by solving a finite horizon optimization problem. The peak shearing force of pier top, the displacement and the acceleration of beam are chosen as control goals, and the vibration isolation rate is applied to characterize the vibration isolation effect.It is noted that MPC method naturally takes the time-delay and uncertain interference into consideration, and significantly improves the control performance of the system. Finally, the numerical example is described and the seismic response of isolated bridge based on MRB is analyzed. The simulation results show that predictive control can be used to control the time-delay of bridge system in different degrees. The best control performance is at0.4 s. Even if the time-delay reaches 2 s, it is still good. Therefore, the control method significantly reduces the adverse effects of time-delay on the system, and has a good vibration isolation performance. 展开更多
关键词 bridge MAGNETORHEOLOGICAL ELASTOMER bearing(MRB) predictive control TIME-DELAY
Trajectory Tracking of Autonomous Vehicle with the Fusion of DYC and Longitudinal–Lateral Control
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作者 Fen Lin Yaowen Zhang +3 位作者 Youqun Zhao Guodong Yin Huiqi Zhang Kaizheng Wang 《中国机械工程学报:英文版》 SCIE EI CAS CSCD 2019年第1期212-227,共16页
The current research of autonomous vehicle motion control mainly focuses on trajectory tracking and velocity tracking. However, numerous studies deal with trajectory tracking and velocity tracking separately, and the ... The current research of autonomous vehicle motion control mainly focuses on trajectory tracking and velocity tracking. However, numerous studies deal with trajectory tracking and velocity tracking separately, and the yaw stability is seldom considered during trajectory tracking. In this research, a combination of the longitudinal–lateral control method with the yaw stability in the trajectory tracking for autonomous vehicles is studied. Based on the vehicle dynamics, considering the longitudinal and lateral motion of the vehicle, the velocity tracking and trajectory tracking problems can be attributed to the longitudinal and lateral control. A sliding mode variable structure control method is used in the longitudinal control. The total driving force is obtained from the velocity error in order to carry out velocity tracking. A linear time-varying model predictive control method is used in the lateral control to predict the required front wheel angle for trajectory tracking. Furthermore, a combined control framework is established to control the longitudinal and lateral motions and improve the reliability of the longitudinal and lateral direction control. On this basis, the driving force of a tire is allocated reasonably by using the direct yaw moment control, which ensures good yaw stability of the vehicle when tracking the trajectory. Simulation results indicate that the proposed control strategy is good in tracking the reference velocity and trajectory and improves the performance of the stability of the vehicle. 展开更多
关键词 Autonomous vehicle TRAJECTORY tracking Direct yaw MOMENT control(DYC) Model PREDICTIVE CONTROL (MPC) Longitudinal–lateral CONTROL
基于模型预测的波能转换装置阵列的控制策略 预览
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作者 Qian Zhong Ronald W. Yeung 《船舶与海洋工程学报:英文版》 CSCD 2019年第1期26-37,共12页
To facilitate the commercialization of wave energy in an array or farm environment, effective control strategies for improving energy extraction efficiency of the system are important. In this paper, we develop and ap... To facilitate the commercialization of wave energy in an array or farm environment, effective control strategies for improving energy extraction efficiency of the system are important. In this paper, we develop and apply model-predictive control(MPC) to a heaving point-absorber array, where the optimization problem is cast into a convex quadratic programming(QP)formulation,which can be efficiently solved by a standard QP solver. We introduced a term for penalizing large slew rates in the cost function to ensure the convexity of this function. Constraints on both range of the states and the input capacity can be accommodated. The convex formulation reduces the computational hurdles imposed on conventional nonlinear MPC. For illustration of the control principles,a point-absorber approximation is adopted to simplify the representation of the hydrodynamic coefficients among the array by exploiting the small devices to wavelength assumption. The energycapturing capabilities of a two-cylinder array in regular and irregular waves are investigated. The performance of the MPC for this two-WEC array is compared to that for a single WEC, and the behavior of the individual devices in head or beam wave configuration is explained. Also shown is the reactive power required by the power takeoff system to achieve the performance. 展开更多
关键词 Wave-energy conversion Wave-energy ARRAYS Point-absorber approximation Model PREDICTIVE control CONVEX formulation
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Initial management for acute lower gastrointestinal bleeding 预览
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作者 Tomonori Aoki Yoshihiro Hirata +1 位作者 Atsuo Yamada Kazuhiko Koike 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第1期69-84,共16页
Acute lower gastrointestinal bleeding(LGIB)is a common indication for hospital admission.Patients with LGIB often experience persistent or recurrent bleeding and require blood transfusions and interventions,such as co... Acute lower gastrointestinal bleeding(LGIB)is a common indication for hospital admission.Patients with LGIB often experience persistent or recurrent bleeding and require blood transfusions and interventions,such as colonoscopic,radiological,and surgical treatments.Appropriate decision-making is needed to initially manage acute LGIB,including emergency hospitalization,timing of colonoscopy,and medication use.In this literature review,we summarize the evidence for initial management of acute LGIB.Assessing various clinical factors,including comorbidities,medication use,presenting symptoms,vital signs,and laboratory data is useful for risk stratification of severe LGIB,and for discriminating upper gastrointestinal bleeding.Early timing of colonoscopy had the possibility of improving identification of the bleeding source,and the rate of endoscopic intervention,compared with elective colonoscopy.Contrast-enhanced computed tomography before colonoscopy may help identify stigmata of recent hemorrhage on colonoscopy,particularly in patients who can be examined immediately after the last hematochezia.How to deal with nonsteroidal antiinflammatory drugs(NSAIDs)and antithrombotic agents after hemostasis should be carefully considered because of the risk of rebleeding and thromboembolic events.In general,aspirin as primary prophylaxis for cardiovascular events and NSAIDs were suggested to be discontinued after LGIB.Managing acute LGIB based on this information would improve clinical outcomes.Further investigations are needed to distinguish patients with LGIB who require early colonoscopy and hemostatic intervention. 展开更多
关键词 Lower GASTROINTESTINAL BLEEDING PREDICTIVE model COLONOSCOPY COMPUTED tomography MEDICATION
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The macular microstructure repair and predictive factors of surgical outcomes after vitrectomy for idiopathic macular hole
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作者 Jing-Ling Zou Jun Zeng 《国际眼科杂志:英文版》 SCIE CAS 2019年第5期852-857,共6页
To evaluate the macular microstructure repair and explore the factors related to those changes and visual improvement after vitrectomy for idiopathic macular hole(IMH). Totally 19 eyes of 18 IMH patients who underwent... To evaluate the macular microstructure repair and explore the factors related to those changes and visual improvement after vitrectomy for idiopathic macular hole(IMH). Totally 19 eyes of 18 IMH patients who underwent macular hole(MH) surgery were evaluated with bestcorrected visual acuity(BCVA) and spectral-domain optical coherence tomography(SD-OCT) images. All 19 eyes closed at 6 mo postoperatively. BCVA was observed gradually improved(P<0.001), with subretinal fluid(SRF) gradually absorbed(P=0.021) and the rate of external limiting membrane(ELM) defects gradually decreased(P=0.011) with follow-up time. Poorer postoperative logMAR BCVA correlated with larger MH minimum diameter(P<0.001), larger MH basal diameter(P=0.008), longer symptom duration(P=0.002) and poorer preoperative logMAR BCVA(P=0.010). More improvement in BCVA correlated only with poorer preoperative in logMAR BCVA(P=0.002). The earlier reconstruction of ELM was associated with smaller MH basal diameter(P=0.022) and shorter symptom duration(P=0.008). In conclusion, smaller basal diameter of MH and shorter symptom duration were key factors in earlier reconstruction of ELM. 展开更多
关键词 IDIOPATHIC MACULAR HOLE MACULAR MICROSTRUCTURE PREDICTIVE factors
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