基于伪故障度生成枚举树的极小诊断求解方法

基于模型诊断(model-based diagnosis,MBD)是人工智能领域一个极富有挑战性的问题.近年来,SAT求解器发展十分迅速,且已被应用于求解基于模型诊断问题并取得了显著成果.在对基于模型诊断问题求解方法 LLBRS-Tree深入研究的基础上,根据电路组件的拓扑结构信息、系统的观测行为和预期行为之间的差异以及集合枚举树的特点,首次提出了组件静态伪故障度和动态伪故障度的概念.计算所有组件的静态伪故障度,并根据静态伪故障度从大到小对组件重新排序,生成新的枚举树;并且在遍历到新的极小诊断解时,更新相关组件的动态伪故障度,动态建立新的枚举树,从而能较快地搜索到极小诊断解,删除大量冗余解,较大程度地减少SAT求解器的调用次数.实验结果表明:随着诊断系统中组件个数的增多以及极小诊断解长度的增加,提出的方法较LLBRS-Tree方法效率提升明显.

Reiter基本定理在连续系统故障诊断中的修正

对 Reiter基本定理在连续系统故障诊断中的应用做了修正。 Reiter的诊断定理是多解的 ,并且各个诊断解的发生概率不同 ,对数字电路的故障诊断其所有解都是可能的。而对连续系统的诊断 ,其一部分解是不可能的。因此 ,本文对连续系统给出一个与 Reiter定理相对应的基本定理 。

Clinical Diagnosis Technique of Goat Pox Disease

[Objective] The aim was to provide theoretical basis for effective prevention of goat pox disease.[Method] 5 cases of infected goats were diagnosed for goat pox with microbiology examination.The poxes on their skin,rumen,reticulum,omasum,abomasum and submandibular lymph nodes,bronchial lymph nodes,lung and spleen were macroscopically and microscopically observed with pathanatomical and histopathological technique.[Result] Poxes on skin mainly showed ashen hemisphere state and gave prominence to the surface of skin; some cases had hemorrhage in the poxes and showed dark purplish red.Poxes on gastric mucosa showed ashen.Cytoplasmic inclusion body could be all observed in epithelial cells of the poxes and macrphages of lymph node,lung and spleen.[Conclusion] Poxes on skin,lung and the surface of gastric mucosa as well as cytoplasmic inclusion body in the epithelial cells of pox and the macrphages of lymphoid organs were the especial pathochanges of goat pox,which could be taken as the proof of goat pox＇s clinic diagnisis.

Anatomical variations of the cystic duct:Two case reports

Anatomical variations of the cystic duct often occur and may be encountered during cholecystectomy. Knowledge of the variable anatomy of the cystic duct and cysticohepatic junction is important to avoid significant ductal injury in biliary surgery. Here, we present two unusual cases with an anomalous cystic duct, namely, low lateral insertion and narrow-winding of the cystic duct. The first case was a 64-year-old man with cholelithiasis and chronic cholecystitis. During surgery, the entrance of the cystic duct was misidentified as being short and leading into the right hepatic duct. Further exploration showed multiple calculi in the right and common hepatic ducts. Cholecystectomy was completed, followed by T-tube drainage of the common and right hepatic ducts. Postoperative T-tube cholangiography demonstrated that the two T tubes were respectively located in the cystic and common hepatic duct. Six weeks later, the retained stones in the distal choledochus were extracted by cholangioscopy through the sinus tract of the T-tube. The second case was a 41-year-old woman, in which, preoperative endoscopic retrograde cholangiopancreatography (ERCP) revealed a long cystic duct, with a narrow and curved-in lumen. The patient underwent open cholecystectomy. Both patients were cured. The authors propose that preoperative ERCP or magnetic resonance cholangiopancreatography (MRCP), and intraoperative cholangiography or cholangioscopy constitute a useful and safe procedure for determining anatomical variations of the cystic duct.

Disturbance decoupled fault diagnosis for sensor fault of maglev suspension system

A disturbance decoupled fault diagnosis strategy is proposed.This disturbance decoupled fault diagnosis is both robust to disturbances and sensitive to sensor faults of magnetic levitation control system.First,a robust controller based on a novel disturbance observer is devised to improve the disturbance attenuation ability,which greatly enhances the robustness of the system.Second,a fault reconstruction technique with adaptive method is presented,along with a strict verification for guaranteeing the robustness of fault.This fault reconstruction technique provides an accurate sensor fault reconstruction.From the results of simulation and experiments conducted on the CMS-04 maglev train,the integrated strategy is robust to model uncertainties of the system and the fault reconstruction algorithm is able to reconstruct the dynamic uncertain faults.

A Fault Diagnosis Approach for Broken Rotor Bars Based on EMD and Envelope Analysis

Empirical Mode Decomposition (EMD) used to deal with non-linear and non-stable signals,is a time-frequency analytical method that has been developed recently. In this paper the EMD method is used to filter the noise from the stator current signal that arises when rotor bars break. Then a Hilbert Transform is used to extract the envelope from the filtered signal. With the EMD method again,the frequency band containing the fault characteris-tic-frequency components,2sf,can be extracted from the signal's envelope. The last step is to use a Fast Fourier Trans-form (FFT) method to extract the fault characteristic frequency. This frequency can be detected in actual data from a faulty motor,as shown by example. Compared to the Extend Park Vector method this method is proved to be more sen-sitive under light motor load.

Anal fistula: Intraoperative difficulties and unexpected findings

Anal fistula surgery is a commonly performed procedure.The diverse anatomy of anal fistulae and their proximity to anal sphincters make accurate preoperative diagnosis essential to avoid recurrence and fecal incontinence.Despite the fact that proper preoperative diagnosis can be reached in the majority of patients by simple clinical examination,endoanal ultrasound or magnetic resonance imaging,on many occasions,unexpected findings can be encountered during surgery that can make the operation difficult and correct decision-making crucial.In this article we discuss the difficulties and unexpected findings that can be encountered during anal fistula surgery and how to overcome them.

Diagnostic model of saliva protein finger print analysis of patients with gastric cancer

AIM:To explore the method for early diagnosis of gastric cancer by screening the expression spectrum of saliva protein in gastric cancer patients using mass spectrometry for proteomics.METHODS:Proportional peptide mass fingerprints were obtained by analysis based on proteomics matrix-assisted laser desorption ionization time-of-flight/mass spectrometry.A diagnosis model was established using weak cation exchange magnetic beads to test saliva specimens from gastric cancer patients and healthy subjects.RESULTS:Significant differences were observed in the mass to charge ratio(m/z) peaks of four proteins(1472.78 Da,2936.49 Da,6556.81 Da and 7081.17 Da) between gastric cancer patients and healthy subjects.CONCLUSION:The finger print mass spectrum of saliva protein in patients with gastric cancer can be established using gastric cancer proteomics.A diagnostic model for distinguishing protein expression mass spectra of gastric cancer from non-gastric-cancer saliva can be established according to the different expression of proteins 1472.78 Da,2936.49 Da,6556.81 Da and 7081.17 Da.The method for early diagnosis of gastric cancer is of certain value for screening special biological markers.

Diagnosis of Valve-Slap of Diesel Engine with EEMD-EMD-AGST Approach

A hybrid of ensemble empirical mode decomposition and empirical mode decomposition (EEMD-EMD) is introduced to diagnose the valve-slap vibration signal,which is relative to the dominant combustion knock vibration signal given out by a diesel engine around the top dead center (TDC).The time-frequency representations of intrinsic mode functions (IMFs) decomposed by EEMD-EMD are obtained by adaptive generalized S transform (AGST).A type 493 diesel engine was used for the experiment,and the result indicates that the valve-slap of the diesel engine is serious,and the vibration frequencies are higher than the combustion knock.With EEMD-EMD-AGST approach,the valve-slap can be identified by the vibration analysis of the diesel engine.

A description of alkaline phosphatases from marine organisms

Alkaline phosphatases(APs) are non-specifi c phosphohydrolases, and they are widely used in clinical diagnostics and biological studies. APs are widespread in nature and exhibit dif ferent structural formulations. Based on the diversity of biogenetic sources, APs exhibit temperature-propensity traits, and they are classifi ed as psychrophilic, mesophilic, and thermophilic. In this article, the characteristics of psychrophilic APs from marine organisms were described, accompanied by a simple description of APs from other organisms. This review will facilitate better utilization of marine APs in the biotechnology fi eld.

Effects of anatomical position on esophageal transit time:A biomagnetic diagnostic technique

AIM： To study the esophageal transit time （ETT） and compare its mean value among three anatomical inclinations of the body; and to analyze the correlation of ETT to body mass index （BMI）. METHODS： A biomagnetic technique was implemented to perform this study： （1） The transit time of a magnetic marker （MM） through the esophagus was measured using two fluxgate sensors placed over the chest of 14 healthy subjects; （2） the EIF was assessed in three anatomical positions （at upright, fowler, and supine positions; 90°, 45° and 0°, respectively）. RESULTS： ANOVA and Tuckey post-hoc tests demonstrated significant differences between E-IT mean of the different positions. The ETT means were 5.2 ± 1.1 s, 6.1 ± 1.5 s, and 23.6 ± 9.2 s for 90°, 45° and 0°, respectively. Pearson correlation results were r = -0.716 and P 〈 0.001 by subjects＇ anatomical position, and r = -0.024 and P 〉 0.05 according the subject＇s BMI. CONCLUSION： We demonstrated that using this biomagnetic technique, it is possible to measure the ETT and the effects of the anatomical position on the ETT.

Proteasome Inhibitors Sensitize Hepatocellular Carcinoma Cells to TRAIL

OBJECTIVE To investigate the effect of proteasome inhibition on the sensitivity of carcinoma cells to TRAIL-inducing apoptosis, and to study the mechanism of the response. METHODS Human hepatocellular carcinoma cells, pretreated with the proteasome inhibitor, MG132, were cotreated with TRAIL. Western blot assays, immunoprecipitation and RT-PCR were performed to test the expression of the Bcl-2 family proteins and Bax mRNA. RESULTS We found that (i) proteasome inhibition sensitized the human hepatocellular carcinoma cells to TRAIL; and (ii) resulted in Bax accumulation before release of cytochrome C and induction of apoptosis. These results were associated with the ability of proteasome inhibitors to overcome Bcl-2-mediated antiapoptotic function; (iii) Bax is regulated by an ubiquitin/proteasome-dependent degradation pathway. CONCLUSION Proteasome inhibition sensitized hepatocellular carcinoma cells to TRAIL by the inhibition of the ubiquitin/proteasome-mediated Bax degradation pathway.

Combined Signal Detection Method in Differential Frequency Hopping System

In order to enhance communication reliability of differential frequency hopping system, a receiver implemented with the concatenation of an optimal subblock-by-subblock maximum a posteriori probability (OBB-MAP) detector and a soft-decision Turbo decoder is proposed and validated in both AWGN and Rayleigh flat fading channels. It is shown that the OBB-MAP decoder can iteratively decode a cyclic trellis, and back-search the trellis for any state to obtain estimates for the prior information bits which can be employed by soft-decision Turbo decoder. The proposed receiver achieves a better bit error rate(BER) performance than maximum likelihood sequence estimation(MLSE) detector employing Viterbi algorithm. The simulation results demonstrate that the combined signal detection method improves communication quality.

Research on Hybrid Renewable Energy Systems with Fault Detection Technology

Early and accurate fault detection and diagnosis for renewable energy systems can increase their safety and ensure the continuity of their service. This paper presents a comprehensive review of different fault detection and diagnosis methods for hybrid renewable energy systems consisting of a wind turbine power generator, a PV （photovoltaic） array, a PEM （polymer electrolyte membrane） fuel cell and a battery storage system. The need of batteries to store the generated power from the solar panel, wind turbine or PEM fuel cell is also emphasized. Finally, an overview of the current methods used in the diagnosing of the lead-acid battery degradation is given.

Concurrent gemcitabine and cisplatin combined with 3D conformal radiotherapy for stage III non-small cell lung cancer

Objective： To study the toxicities and efficacy of concurrent gemcitabine plus cisplatin combined with three-dimensional conformal radiotherapy for stage Ⅲ non-small cell lung cancer （NSCLC）. Methods： Thirty-six patients with pathologically diagnosed NSCLC received radiotherapy and concurrent chemotherapy. There were 22 patients with stage Ilia and 14 patients with IIIb. Radiotherapy was given a total of 60-70 Gy in conventional fractionation. Chemotherapy included gemcitabine （600 mg/m^2） and cisplatin （20 mg/m^2）, once per week. Results： Thirty-two patients received a total dose of 60-72 Gy. Two patients received 56 Gy and another two patients received 58 Gy. Thirty-four patients received 4-6 weeks of chemotherapy, while two patients received only 2 weeks of chemotherapy. The overall response rate （CR ＋ PR）, complete response rate （CR）, partially response rate （PR） were 83.3% （30/36）, 11.1% （4/36） and 72.2% （26/36） respectively. The median follow-up duration was 18.4 months. The 1- and 2-year overall survival rates were 77.8% （28/36） and 55.6% （20/36）, respectively. Conclusion： Concurrent gemcitabine and cisplatin combined with three-dimensional conformal radiotherapy for stage III non-small cell lung cancer is effective and well tolerated. Lone-term results need further study.

Impulsive component extraction using shift-invariant dictionary learning and its application to gear-box bearing early fault diagnosis

The impulsive components induced by bearing faults are key features for assessing gear-box bearing faults.However,because of heavy background noise and the interferences of other vibrations,it is difficult to extract these impulsive components caused by faults,particularly early faults,from the measured vibration signals.To capture the high-level structure of impulsive components embedded in measured vibration signals,a dictionary learning method called shift-invariant K-means singular value decomposition(SI-K-SVD)dictionary learning is used to detect the early faults of gear-box bearings.Although SI-K-SVD is more flexible and adaptable than existing methods,the improper selection of two SI-K-SVD-related parameters,namely,the number of iterations and the pattern lengths,has an adverse influence on fault detection performance.Therefore,the sparsity of the envelope spectrum(SES)and the kurtosis of the envelope spectrum(KES)are used to select these two key parameters,respectively.SI-K-SVD with the two selected optimal parameter values,referred to as optimal parameter SI-K-SVD(OP-SI-K-SVD),is proposed to detect gear-box bearing faults.The proposed method is verified by both simulations and an experiment.Compared to the state-of-the-art methods,namely,empirical model decomposition,wavelet transform and K-SVD,OP-SI-K-SVD has better performance in diagnosing the early faults of a gear-box bearing.

Application of empirical mode decomposition in early diagnosis of magnetic memory signal

In order to eliminate noise interference of metal magnetic memory signal in early diagnosis of stress concentration zones and metal defects, the empirical mode decomposition method combined with the magnetic field gradient characteristic was proposed. A compressive force periodically acting upon a casing pipe led to appreciable deformation, and magnetic signals were measured by a magnetic indicator TSC-1M-4. The raw magnetic memory signal was first decomposed into different intrinsic mode functions and a residue, and the magnetic field gradient distribution of the subsequent reconstructed signal was obtained. The experimental results show that the gradient around 350 mm represents the maximum value ignoring the marginal effect, and there is a good correlation between the real maximum field gradient and the stress concentration zone. The wavelet transform associated with envelop analysis also exhibits this gradient characteristic, indicating that the proposed method is effective for early identifying critical zones.

系统性红斑狼疮合并大疱表皮松解型药疹1例分析

我科2010—08—10收治1例系统性红斑狼疮（SLE）伴大泡表皮松解型药疹并发肝功能严重损害及下消化道出血的患者，经中西医结合疗法救治痊愈出院，现介绍如下。

Multi-scale bistable stochastic resonance array: A novel weak signal detection method and application in machine fault diagnosis

Weak signal detection based on stochastic resonance （SR） can hardly succeed when noise intensity exceeds the optimal value of SR. This paper explores a novel parallel bistable SR array mechanism by decomposed multi-scale noises from input signal. A smoother output with lower noise is obtained from the combination of colored noise SR ellect and parallel bistable SR array. The influence of noise intensity and array size on the SR effect and output noise intensity is analyzed through numerical simu- lation. A signal detection method based on the new SR mechanism and normalized scale transform is proposed for the case of heavy background noise. Simulation is conducted to confirm the effectiveness of parameter tuning and amplitude tuning of normalized scale transform on the proposed SR model. The proposed method has three advantages： the input noise intensity of each unit is reduced by wavelet decomposition; the output noise level decreases due to array ensemble average; the SR effect of each unit is optimized by normalized scale transform for high frequency signal. Experiment on bearing inner and outer race fault diagnosis has verified the effectiveness and advantages of the proposed SR model in comparison with traditional SR method and kurlogram.