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Remaining Useful Life Prediction for Aero-Engines Combining Sate Space Model and KF Algorithm

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Transactions of Nanjing University of Aeronautics and Astronautics 2017年第3期34卷 265-271页

作者： cai Jing Zhang Li Dong ping College of Civil Aviation Nanjing University of Aeronautics and Astronautics

The key to failure prevention for aero-engine lies in performance prediction and the exhaust gas temperature margin(EGTM)is used as the most important degradation parameter to obtain the operating performance of the *** of the complex environment interference,EGTM always has strong randomness,and the state space based degradation model can identify the noisy observation from the true degradation state,which is more close to the actual ***,a state space model based on EGTM is established to describe the degradation path and predict the remaining useful life(RUL).As one of the most effective methods for both linear state estimation and parameter estimation,Kalman filter(KF)is ***,with EGTM degradation data,state space model approach is used to set up a state space model for ***,RUL of aero-engine is analyzed,and expected RUL and distribution of RUL are ***,the sate space model and KF algorithm are applied to an example of *** expected RUL is predicted,and corresponding probability density distribution(PDF)and cumulative distribution function(CDF)are *** result indicates that the accuracy of RUL prediction reaches 7.76%ahead 580 flight cycles(FC),which is more accurate than linear regression,and therefore shows the validity and rationality of the proposed method.

关键词： Prediction remaining noisy situations exhaust ahead rationality validity cumulative Bayesian

Higher-order principal component pursuit via tensor approximation and convex optimization

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Journal of Systems Engineering and Electronics 2014年第3期25卷 523-530页

作者： Sijia cai ping Wang Linhao Li Chuhan Zhang School of Science Tianjin University Center for Applied Mathematics Tianjin University

Recovering the low-rank structure of data matrix from sparse errors arises in the principal component pursuit （PCP）. This paper exploits the higher-order generalization of matrix recovery, named higher-order principal component pursuit （HOPCP）, since it is critical in multi-way data analysis. Unlike the convexification （nuclear norm） for matrix rank function, the tensorial nuclear norm is stil an open problem. While existing preliminary works on the tensor completion field provide a viable way to indicate the low complexity estimate of tensor, therefore, the paper focuses on the low multi-linear rank tensor and adopt its convex relaxation to formulate the convex optimization model of HOPCP. The paper further propose two algorithms for HOPCP based on alternative minimization scheme： the augmented Lagrangian alternating direction method （ALADM） and its truncated higher-order singular value decomposition （ALADM-THOSVD） version. The former can obtain a high accuracy solution while the latter is more efficient to handle the computationally intractable problems. Experimental results on both synthetic data and real magnetic resonance imaging data show the applicability of our algorithms in high-dimensional tensor data processing.

关键词： tensor recovery principal component pursuit alternating direction method tensor approximation.

Comprehensive assessment on dynamic roof instability under fractured rock mass conditions in the excavation disturbed zone

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International Journal of Minerals,Metallurgy and Materials 2009年第1期16卷 12-18页

作者： Xing-ping Lai Fen-hua Ren Yong-ping Wu Mei-feng cai Energy School Xi＇an University of Science ＆ Technology Xi＇an 710054 China School of Civil and Environmental Engineering University of Science and Technology Beijing Beijing 100083 China Key Laboratory of Western Mine ＆ Hazard Prevention China Ministry of Education Xi＇an 710054 China

The damage process of fractured rock mass showed that the fracture in rocks induced roof collapse in Yangchangwan Coal Mine, China. The rock mass was particularly weak and fractured. There occurred 6 large-scale dynamical roof falls in the excavation disturbed zone （EDZ） with the collapsing volume of 216 m^3. First, the field detailed geological environment, regional seismic dynamics, and dynamic instability of roadways were generally investigated. Second, the field multiple-index monitoring measurements for detecting the deep delamination of the roof, convergence deformation, bolt-cable load, acoustic emission （AE） characteristic parameters, total AE events, AE energy-releasing rate, rock mass fracture, and damage were arranged. Finally, according to the time-space-strength relations, a quantitative assessment of the influence of rock-mass damage on the dynamic roof instability was accomplished.

关键词： fractured rock mass excavation disturbed zone (EDZ) roof collapse acoustic emission (AE) quantitative assessment

自体骨与富血小板纤维蛋白修复牙槽骨重度缺损

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中国组织工程研究 2025年第10期29卷 2044-2051页

作者：刘子略王智宋文尚李苏娜蔡世新衡水市人民医院口腔正畸修复科河北省衡水市053000 衡水市人民医院神经内科河北省衡水市053000

背景:有研究将富血小板纤维蛋白与自体骨联合应用于牙周骨缺损治疗取得了良好效果,但二者联合治疗牙槽骨重度缺损的研究目前较为匮乏。目的:观察自体骨移植与富血小板纤维蛋白联合修复牙槽骨重度缺损的效果。方法:选择2022年4月至2023年... 详细信息

背景:有研究将富血小板纤维蛋白与自体骨联合应用于牙周骨缺损治疗取得了良好效果,但二者联合治疗牙槽骨重度缺损的研究目前较为匮乏。目的:观察自体骨移植与富血小板纤维蛋白联合修复牙槽骨重度缺损的效果。方法:选择2022年4月至2023年2月衡水市人民医院收治的102例牙槽骨重度缺损患者,采取随机数字表法分为对照组(n=51)与观察组(n=51),两组患者均进行引导性组织再生手术,对照组术中采用自体骨填充骨缺损,观察组术中采用自体富血小板纤维蛋白与自体骨填充骨缺损。观察两组临床疗效、手术前后牙齿松动度、牙周微生态环境(探诊深度、临床附着丧失、出血指数)、牙槽骨高度及密度、龈沟液指标(转化生长因子β、丝氨酸蛋白酶抑制剂、基质金属蛋白酶3)变化及不良反应情况。结果与结论:术后6个月,两组治疗有效率比较差异无显著性意义(P> 0.05);观察组患者术后3,6个月的牙齿松动度及牙周探诊深度、临床附着丧失、出血指数均低于对照组(P <0.05),术后6个月的牙槽骨高度高于对照组(P <0.05),术后3,6个月的龈沟液转化生长因子β水平高于对照组(P <0.05),术后3,6个月的龈沟液丝氨酸蛋白酶抑制剂、基质金属蛋白酶3水平均低于对照组(P <0.05)。结果提示:在引导性组织再生手术中,采用自体富血小板纤维蛋白与自体骨联合填充可改善牙槽骨重度缺损患者的牙周微生态环境、减轻牙龈组织炎症、促进牙槽骨组织再生与修复、降低牙齿松动度。

关键词：牙槽骨缺损自体骨富血小板纤维蛋白引导骨组织再生骨移植材料

Stroke-GAN Painter:Learning to paint artworks using stroke-style generative adversarial networks

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Computational Visual Media 2023年第4期9卷 787-806页

作者： Qian Wang cai Guo Hong-Ning Dai ping Li School of Computer Science and Engineering Macao University of Science and TechnologyMacaoChina Department of Computing The Hong Kong Polytechnic UniversityHong KongChina School of Computing and Information Engineering Hanshan Normal UniversityChaozhouChina Department of Computer Science Hong Kong Baptist UniversityHong KongChina School of Design The Hong Kong Polytechnic UniversityHong KongChina

It is a challenging task to teach machines to paint like human artists in a stroke-by-stroke *** advances in stroke-based image rendering and deep learning-based image rendering,existing painting methods have limitations:they(i)lack flexibility to choose different art-style strokes,(ii)lose content details of images,and(iii)generate few artistic styles for *** this paper,we propose a stroke-style generative adversarial network,called Stroke-GAN,to solve the first two ***-GAN learns styles of strokes from different stroke-style datasets,so can produce diverse stroke *** design three players in Stroke-GAN to generate pure-color strokes close to human artists’strokes,thereby improving the quality of painted *** overcome the third limitation,we have devised a neural network named Stroke-GAN Painter,based on Stroke-GAN;it can generate different artistic styles of *** demonstrate that our artful painter can generate various styles of paintings while well-preserving content details(such as details of human faces and building textures)and retaining high fidelity to the input images.

关键词： AI painting painting strokes artistic style

Multisymplectic Scheme for the Improved Boussinesq Equation

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Chinese Physics Letters 2013年第7期30卷 5-8页

作者： cai Jia-Xiang QIN zhi-Lin BAI Chuan-zhi School of Mathematics Science Huaiyin Normal UniversityHuai'an 223300 Jiangsu Key Laboratory for NSLSCS School of Mathematics ScienceNanjing Normal UniversityNanjing 210046

We first note that the improved Boussinesq equation has a multisymplectic *** on it,a multisymplectic scheme is *** relations analysis and linear stability analysis show that the proposed scheme has excellent *** resu... 详细信息

关键词： properties. structure. Boussinesq

A facile approach to asymmetrical biaryls via coupling reaction of aryl halides with sodium tetraphenylborate catalyzed by MCM-41-supported sulfur palladium(0) complex

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Chinese Chemical Letters 2007年第4期18卷 387-389页

作者： Qiu Hua Xu ping ping Wang Ming Zhong cai Department of Chemistry Jiangxi Normal University 330027 Nanchang China Department of Chemistry Jiujiang University 332000 Jiujiang China

Various functionalized asymmetrical biaryls can be synthesized in high to excellent yields via coupling reaction of aryl iodides or bromides with NaBPh4 catalyzed by MCM-41-supported sulfur palladium（0） complex. Thi... 详细信息

关键词： Asymmetrical biaryl NaBPh4 Aryl halide Palladium Coupling reaction

Decoding the electron dynamics in high-order harmonic generation from asymmetric molecular ions in elliptically polarized laser fields

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Chinese Physics B 2022年第4期31卷 287-292页

作者： cai-ping Zhang Xiang-Yang Miao College of Physics and Information Engineering Shanxi Normal UniversityTaiyuan 030031China Key Laboratory of Spectral Measurement and Analysis of Shanxi Province Shanxi Normal UniversityTaiyuan 030031China

The high-order harmonic generation from an asymmetric molecular ion is theoretically investigated based on the Born-Oppenheimer model with two-dimensional electron *** is shown that the harmonic intensity changes periodically in elliptically polarized laser *** periodical character is *** establishing the physical image,the periodicity of the harmonic intensity can be ascribed to the contributions of the ground state and the excited ***,the electron dynamics from different electronic states can be selected via combining the elliptically polarized laser field with a static electric *** harmonics dominated either by ground state or excited state are emitted once in an optical cycle in the combined laser field.

关键词： asymmetric molecular ion high-order harmonic generation electron dynamics elliptically polarized laser field

L-Proline as an efficient and reusable promoter for the synthesis of coumarins in ionic liquid

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第12期9卷 990-995页

作者： Xiu-hong LIU Ji-cai FAN Yang LIU zhi-cai SHANG Department of Chemistry Zhejiang University Hangzhou 310027 China

The effect of L-proline as a promoter on the condensation reaction of salicylaldehyde or its derivatives with ethyl acetoacetate in neutral ionic liquid [emim]BF4 was studied. All reactions were carried out under mild reaction conditions and achieved high yields. Moreover, the ionic liquid containing L-proline could be recycled and reused for several times without noticeably decreasing in productivity. The results show that the L-proline-[emim]BF4 system has a potential in contribution to the development of environmentally friendly and inexpensive processes in organic syntheses.

关键词： L-Proline Ionic liquid Coumarins Knoevenagel condensation