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Accuracy analysis of a single-fault Markov model for FADEC system

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Journal of Systems Engineering and Electronics 2019年第5期30卷 1044-1052页

作者： cai jing HU Wei cai Kunye College of Civil Aviation Nanjing University of Aeronautics and Astronautics

Time-limited dispatching(TLD)analysis of the full authority digital engine control(FADEC)systems is an important part of the aircraft system safety analysis and a necessary task for the certification of commercial aircraft and *** the time limited dispatch guidance document ARP5107B,a single-fault Markov model(MM)approach is proposed for TLD ***,ARP5107B also requires that the loss of thrust control(LOTC)rate error calculated by applying the single-fault MM must be less than 5%when performing airworthiness ***,the sources of accuracy errors in three kinds of MM are analyzed and specified through a case study of the general FADEC system,and secondly a two-fault MM considering maintenance policy is established through analyzing and calculating the expected repair time when two related faults ***,a specific FADEC system is given to study on the influence factors of accuracy error in the single-fault MM,and the results show that the accuracy error of the single-fault MM decreases with the increase of short or long prescribed dispatch time,and the range values of short time(ST)and long time(LT)are determined to satisfy the requirement of accuracy error within 5%.

关键词： full authority digital engine control(FADEC)system Markov model(MM) accuracy analysis loss of thrust control(LOTC)

Joint optimization of maintenance inspection and spare provisioning for aircraft deteriorating parts

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Journal of Systems Engineering and Electronics 2017年第6期28卷 1133-1140页

作者： jing cai Xin Li Xi Chen College of Civil Aviation Nanjing University of Aeronautics and Astronautics Shanghai Aircraft Customer Service Co. Ltd.

With the wide application of condition based maintenance(CBM) in aircraft maintenance practice, the joint optimization of maintenance and inventory management, which can take full advantage of CBM and reduce the aircraft operational cost, is receiving increasing attention. In order to optimize the inspection interval, maintenance decision and spare provisioning together for aircraft deteriorating parts, firstly, a joint inventory management strategy is presented, then, a joint optimization of maintenance inspection and spare provisioning for aircraft parts subject to the Wiener degradation process is proposed based on the ***, a combination of the genetic algorithm(GA) and the Monte Carol method is developed to minimize the total cost ***, a case study is conducted and the proposed joint optimization model is compared with the existing optimization model and the airline real case. The results demonstrate that the proposed model is more beneficial and effective. In addition, the sensitivity analysis of the proposed model shows that the lead time has higher influence on the optimal results than the urgent order cost and the corrective maintenance cost, which is consistent with the actual situation of aircraft maintenance practices and inventory management.

关键词： joint optimization maintenance spare provision aircraft part Wiener process

Comparative Studies of Two Major Sets of Tibetan Medical Paintings: A Historical Perspective

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Chinese Journal of Integrative Medicine 2019年第11期25卷 803-811页

作者： ZHEN Yan cai jing-feng China Institute for History of Medicine and Medical Literature China Academy of Chinese Medical Sciences

Tibetan medicine, one of the time-honored medical systems in the world, has increasingly been receiving attention the world over. Tibetan medical paintings (TMP, tib. Smart thang) has become one of the focal points in the studies of this medical system. To date, there are many atlases and publications on TMP, which are principally based on the two major sets of TMP series existing today in the world, the Lhasa set and the Buryat set. It has been found that the Buryat set is based on the Lhasa set, which was brought in late 19th to the first half of the 20th century from Tibet to Buryatia, Russia. A careful investigation on the basic structure of the two sets reveals that there are many differences between the two sets of paintings, including the total number of the paintings invoIved, of which some are missing in one set, the details of the captions of some of the paintings, the existenee of the 80th painting and its supervisor, and the overall order of the entire set, etc. The details of the differences are elaborated and discussed, and the prospective of developing the research to arrive at a standard and perfect TMP set in the future is also analyzed and anticipated.

关键词： Tibetan medical painting Sman thang Lhasa set Buryat set Tibetan painting art Sde srid Sangs rgyas rgya mtsho

Global Existence of Strong Solutions for the Generalized Navier-Stokes Equations with Damping

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Acta Mathematicae Applicatae Sinica 2022年第3期38卷 627-634页

作者： Xiao-jing cai Yan-jie ZHOU School of mathematics and statistics Beijing Technology and Business UniversityBeijing 100048China

This paper mainly focus on the global existence of the strong solutions for the generalized NavierStokes equations with damping. We obtain the global existence and uniqueness when α ≥5/4 for β ≥ 1 and when 1/2+β/... 详细信息

关键词： generalized Navier-Stokes equations damping global existence

Hydrate-based carbon dioxide capture from simulated integrated gasification combined cycle gas

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Journal of Natural Gas Chemistry 2012年第5期21卷 501-507页

作者： Chungang Xu Xiaosen Li jing cai Zhaoyang Chen Key Laboratory of Renewable Energy and Gas Hydrate Guangzhou Institute of Energy ConversionChinese Academy of SciencesGuangzhou 510640GuandongChina Guangzhou Center for Gas Hydrate Research Chinese Academy of SciencesGuangzhou 510640GuangdongChina Graduate University of Chinese Academy of Sciences Beijing 100083China

The equilibrium hydrate formation conditions for CO2/H2 gas mixtures with different CO2 concentrations in 0.29 mol% TBAB aqueous solution are firstly *** results illustrate that the equilibrium hydrate formation pressure increases remarkably with the decrease of CO2 concentration in the gas *** on the phase equilibrium data,a three stages hydrate CO2 separation from integrated gasification combined cycle （IGCC） synthesis gas is *** the separation efficiency is quite low for the third hydrate separation,a hybrid CO2 separation process of two hydrate stages in conjunction with one chemical absorption process （absorption with MEA） is proposed and *** experimental results show H2 concentration in the final residual gas released from the three stages hydrate CO2 separation process was approximately 95.0 mol% while that released from the hybrid CO2 separation process was approximately 99.4 mol%.Thus,the hybrid process is possible to be a promising technology for the industrial application in the future.

关键词： integrated gasification combined cycle (IGCC) gas hydrate CO2 separation H2 purification chemical absorption

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

Joint Optimization Scheme Based on Beam Selection and Interference Cancellation in Lens Millimeter Wave NOMA Systems

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China Communications 2022年第4期19卷 57-66页

作者： Lei Xu jing cai jing Chang Hongyu Fang Xiaohui Li School of Electronics and Information Engineering Anhui UniversityHefei 230601China

Non-orthogonal multiple access(NOMA)has been integrated in millimeter-wave(mmWave)Massive MIMO systems to further enhance the spectrum efficiency, but NOMA has not been fully considered in lens mmWave systems. The fusion of these two technologies requires the joint design of beam selection and interference cancellation. In addition, when users follow the spatial cluster distribution, although the user clustering schemes based on K-means algorithm have been applied, the influence of the virtual and actual cluster center users on achievable sum rate has not been differentiated and analyzed in detail. To solve the above problems, a joint optimization scheme is proposed to maximize the achievable sum rate. The optimization problem is NP-hard, which is solved by using the divide-and-conquer approach. Concretely,based on the signal power loss analysis of directional deviation, a beam selection algorithm is designed for inter-cluster interference cancellation based on the Kmeans algorithm. Further for intra-cluster interference cancellation, a power allocation algorithm based on the bisection method is designed to guarantee the fairness of users in each cluster. The simulation results show that the proposed scheme offers a significant performance improvement in terms of both achievable sum rate and energy efficiency, and it is suitable for the large-scale user scenario due to its low complexity.

关键词： lens mmWave systems NOMA user clustering beam selection power allocation

Near-infrared diffuse reflectance spectroscopy with sample spots and chemometrics for fast determination of bovine serum albumin in micro-volume samples

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Chinese Chemical Letters 2013年第1期24卷 67-69页

作者： cai-jing Cui Wen-Sheng cai Xue-Guang Shao Research Center for Analytical Sciences College of ChemistryNankai University

Near-infrared diffuse reflectance spectroscopy （NIRDRS） has attracted more and more attention in analyzing the components in samples with complex matrices. However, to apply this technique to micro-analysis, there are still some obstacles to overcome such as the low sensitivity and spectral overlapping associated with this approach. A method for fast determination of bovine serum albumin （BSA） in micro-volume samples was studied using NIRDRS with sample spots and chemometric techniques. 10 p^L of sample spotted on a filter paper substrate was used for the spectral measurements. Quantitative analysis was obtained by partial least squares （PLS） regression with signal processing and variable selection. The results show that the correlation coefficient （R） between the predicted and the reference concentration is 0.9897 and the recoveries are in the range of 87.4%-114.4% for the validation samples in the concentration range of 0.61-8.10 mg/mL. These results suggest that the method has the potential to quickly measure proteins in micro-volume solutions.

关键词： Near-infrared diffuse reflectancespectroscopySample spotFilter paperProteinMicro-volume analysis

Effects of glossy privet fruit on neural cell apoptosis in the cortical parietal lobe and hippocampal CA1 region of vascular dementia rats

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Neural Regeneration Research 2008年第11期3卷 1192-1196页

作者： jing cai Fan Zhou Jian DU Academy of Integrative Medicine Fujian University of Traditional Chinese Medicine Fuzhou 350003 Fujian Province China Fujian Institute of Traditional Chinese Medicine Fuzhou 350003 Fujian Province China

BACKGROUND： Glossy privet fruit inhibits neural cell apoptosis following the onset of vascular dementia. OBJECTIVE： To confirm glossy privet fruit effects on neural cell apoptosis in the cortical parietal lobe and hippocampal cai region of rat models of vascular dementia using molecular biology techniques. DESIGN, TIME AND SETTING： The neural cell morphology experiment was performed at the Laboratory of Flow Cells and Biochemistry, Academy of Integrative Medicine, Fujian University of Traditional Chinese Medicine, and the Basic Room of Pathology, Academy of Chinese Medicine from December 2006 to May 2008. MATERIALS： A total of 60 Wistar rats were used to establish vascular dementia models using a photochemical reaction method. Glossy privet fruit was purchased from Fujian, China. Hydergine was co-produced by Sandoz, Switzerland and Huajin, China. METHODS： The 60 Wistar rats were randomly divided into 6 equal sized groups （n = 10）, i.e. model, blank, high, moderate and low doses of Chinese medicine, and hydergine control groups. Rats in the model group were treated with distilled water （1 mL/100 g） by gavage following model establishment. Rats in the blank group underwent experimental procedures as for the model group, except that rat models were created without illumination. Rats in the high, moderate and low doses of Chinese medicine groups, and the hydergine control group respectively received high, moderate and low doses of glossy privet fruit, and hydergine suspension （1 mL/100 g） by gavage, once a day, for 30 days. MAIN OUTCOME MEASURES： Morphology of neural cells from the rat cortical parietal lobe and hippocampal CA1 region of all groups was observed with an electron microscope. Positive neural cells in the injury site of the rat cortical parietal lobe and hippocampal CA1 region were investigated using the Fas immunohistochemieal method. Absorbance of Fas-positive neurons was detected by the MPIAS-500 multimedia color imaging analysis system. RESULTS： Neural

关键词： glossy privet fruit cell apoptosis vascular dementia