Object oriented fault diagnosis system for space shuttle main engine redlines

A great deal of attention has recently been given to Artificial Intelligence research in the area of computer aided diagnostics. Due to the dynamic and complex nature of space shuttle red-line parameters, a research effort is under way to develop a real time diagnostic tool that will employ historical and engineering rulebases as well as a sensor validity checking. The capability of AI software development tools (KEE and G2) will be explored by applying object oriented programming techniques in accomplishing the diagnostic evaluation

Breakdown voltage modelling for leatherite paper dielectrics using fuzzy logic technique & estimating the lifetime using step-stress test

OBJECTIVE The real insulation systems are often heterogeneous and some times nonlinear. Quality of insulation is accessed in terms of break down strengths. Partial discharge caused in insulation system by local defects and the resultant overstressing caused by them ultimately lead to breakdown. So the estimation has to be done properly to save insulation from failure. The use of modern computers in bdv analysis has lead to the estimation based on fuzzy logic modeling. The mamdani fuzzy logic using triangular and trapezoidal mf used for the modeling. The bdv got from the modeling section is used to get the weibull parameters using MLE. The shape parameters are used for the life estimation of the dielectric. DESCRIPTION Fuzzy logic modeling is widely used in those fields where the boundary between having a property and not having it is not sharp. The construction of this model can be viewed as a process in which a collection of objects called variables and parameters of the model are related by some other objects called the operators of the model. In the present case it is tried to estimate the bdv of dielectrics depending upon various input conditions. The most important source of partial discharge and breakdown in dielectrics is the voids. Voids are produced due to process control errors at the time of production of most of the solid dielectrics. This is a gas discharged event. The test dielectric is taken as leatherite paper and the estimation is based on data experimentally generated in the laboratory using a CIGRE-2 electrode. The choice of test procedure to know the breakdown voltage of a typical insulation material on insulation system is determined by the test objective. Constant voltage tests provide reliable comprehensive data for the distribution function of the breakdown time but is very time consuming. An accelerated test with increase in voltage stress in discrete steps is quite often used for an electrical insulation study and is widely accepted by the insulation designers. With this method the stress at which the insulation breaks down and time to failure is taken as 6 observed variable The effect of void dimensions on the output is studied and implemented in MATLAB environment. The various steps in modeling include study of the range variation, grouping, rule list generation and simulation. Present system is a MISO system having three inputs (thickness of dielectric, depth and diameter of void) and one output (bdv). The min max algorithm is used as t-norm and s-norm operator. Coa is used for difuzzification. Programming approach is adopted for estimation. The surface plot is plotted to study the variation. Weibull probability has gained wide acceptance in the statistical treatment of time to electrical breakdown of solid dielectrics. It seems to fit experimental data well. MLE is used for parameter estimation. Confidence interval is chosen to get lower and upper limits of the parameters within which the estimation lie for a surety. Throughout the experiment the step stress test is considered. The inverse power law is applied to life estimation. From the slope of the graph the slope is to be found out and used for estimating the life. RESULTS In the mamdani fuzzy logic modeling using the triangular and trapezoidal mf the Mae is found out to be 1.4% and 1.324% respectively. The weibull parameters and life estimation values have close resemblance with the experimentally generated value. CONCLUSION Fuzzy logic provides an easier and a better computation technique based on the fuzzyness of rules. By accurately choosing the parameters and deciding the rule bases the error can be significantly reduced. The weibull parameter calculation using MLE and lifetime also found to be in good agreement. Thus the results indicates that the modeling can be well implemented for such kind of estimation

Fracture union and complication following internal fixation of clavicle by plate and screw

Background: Among all long bones clavicle is the only bone placed horizontally and has membranous ossification. Clavicle fractures accounting for about 2.6% of total body fractures and 34% to 45% of total shoulder girdle injuries in adults. Most fractures occur in middle third of clavicle and common in young male patients. It has wide range of management from conservative to variant internal fixation. Each procedure has its own outcome and complications. We tried to find out the outcome and complications following internal fixation of clavicle with plate and screws.Methods: In a prospective study 50 patients of fracture mid shaft clavicle who were treated with plate and screw were followed for a period of two years. Only adults more than 18 years were included in the study. All patients were followed at 2nd post-operative day 5th post-operative day 14th post-operative day and at 1, 2, 6, 12 and 24 months. Only two parameters were observed i.e. union of fracture and post-operative complications.Results: Of all patients operated with plate and screw 48 patients had good radiological union by six months. Only two patients had non-union and one with implant failure at 12 months. Of complications one had stitch abscess and seven had hardware discomfort.Conclusions: Clavicle fracture in adults has multimodal treatment option. Though conservative management has good results it has high chance of mal-union and non-union. Operative fixation should be opted for adult individuals where chance of non-union is high. Plate and screw fixation has good results in terms of union with least complication.

MOTION ARTIFACT CANCELLATION IN AMBULATORY ECG MEASUREMENT SYSTEM FOR THE DETECTION OF CARDIAC DISEASES

Abstract-In this work, a simple and efficient artifact cancellation in ambulatory ECG using adaptive filter is designed for the detection of different cardiac diseases like bradycardia, tachycardia, left ventricular hypertrophy and right ventricular hypertrophy. Our work is focused on extraction of noise free ECG signal and the real-time implementation of artifacts removal techniques. As ECG signal is very sensitive in nature, and even if small noise mixed with original signal the various characteristics of the signal changes, data corrupted with noise must either filtered or discarded, filtering is important issue for design consideration of real-time ECG measurement systems. Here we have implemented different adaptive filtering algorithms (LMS-Least Mean Square, RLS-Recursive Least Squares) using virtual instrumentation technique to minimize the noisy components and to analyze different cardiac diseases like bradycardia, tachycardia, left ventricular hypertrophy and right ventricular hypertrophy. Finally the overall performance of LMS and RLS algorithm is also compared according to the error signal generated by the techniques

Transcriptional reprogramming under vancomycin pressure in Staphylococcus aureus

534-545The World Health Organization (WHO) has defined Vancomycin intermediate Staphylococcus aureus (VISA) and Vancomycin resistant Staphylococcus aureus (VRSA) as high priority pathogens. VISA and VRSA are produced by different mechanisms, hence VISA cannot convert to VRSA. Consequently, upon vancomycin treatment of VSSA isolates, there can be emergence of VISA but not its conversion to VRSA. But we observed that when VSSA (MIC ≤2 μg/mL) isolates, lacking vanA or vanB genes, are grown under vancomycin stress for 60 days, 4 out of 8 isolates get converted to VISA (MIC = 4-8 μg/mL), and 1 converted to VRSA (MIC ≥16 μg/mL). Further, the VRSA isolate had a vancomycin MIC that was 8-fold higher than that of its sensitive counterpart. Hence, the VRSA has been interpreted as a heteroresistant isolate. To dissect the molecular underpinning of this transient resistance pattern, we analyzed the gene expression profile of these isolates and publicly available datasets. pbp2 gene was observed to be consistently upregulated in all the VISA isolates except the heteroresistant isolate. Pathway analysis revealed upregulation of peptidoglycan biosynthesis in VISA isolates. However, the distinct transcriptional profile of the heteroresistant isolate (with upregulation of recR, ureC and atl) suggests potential role of increased mutation due to SOS response or biofilm formation in this phenotype

Sufficient conditions for extremum of fractional variational problems

Sufficient conditions for extremum of fractional variational problems are formulated with the help of Caputo fractional derivatives. The Euler–Lagrange equation is defined in the Caputo sense and Jacobi conditions are derived using this. Again, Wierstrass integral for the considered functional is obtained from the Jacobi conditions and the transversality conditions. Further, using the Taylor’s series expansion with Caputo fractional derivatives in the Wierstrass integral, the Legendre’s sufficient condition for extremum of the fractional variational problem is established. Finally, a suitable counterexample is presented to justify the efficacy of the fresh findings

Investigation of Physiochemical and Thermal Properties of Eichhornia Crassipes Fibers

The physical, chemical, structural, crystallographic, thermal and surface topographical properties of fiber extracted from the steam of Eichhornia crassipes (EC) plant was characterized for the first time in this study. Physical and chemical analysis results revealed that Eichhornia crassipes fiber (ECF) has comparatively lower density (1350 kg/m3) and higher cellulose content (59.86 wt.%). The chemical functional groups and relevant chemical composition of the ECF were documented by the FTIR. The XRD results acknowledged that ECF has the crystallinity index (44.32%) and crystalline size of 5.09 nm, respectively. Thermogravimetric analysis (TGA) and differential scanning calorimeter analysis (DSC) results of ECF exhibited that it can be thermally stable up to 200° C. All the results of ECF establish that it is a suitable substitute for the artificial fibers used as reinforcement in fiber-reinforced plastics

Second-Order Symmetric Duality And Variational Problems

The concept of second-order symmetric duality of the variational problem is studied in the present investigation. Appropriate duality results for a pair of second order symmetric variational problems are established under generalized invexity assumptions. It is observed that some of the known results in the literature are the particular cases of our work

A numerical study of the wall effects for Newtonian fluid flow over a cone

The effect of blockage ratio i.e. ratio of diameter of cone, d and flow channel, D on the drag coefficients due to Newtonian fluid flow over cone is studied numerically by solving the CFD equations in Ansys FLUENT. The drag coefficients (CD) as a function of Reynolds number (Re) and d/D are reported in the range of Re: 0.01–30,000 and d/D: 0.0015–0.9. The obtained CD values are higher for confined flow (high d/D) than unconfined flow. Validity of CDRe2=constant is ascertained for the confined Newtonian fluid flow over the cone. The variations of angle of separation and its effect on the drag coefficients are examined and justified. The comparative studies among the drag coefficients of sphere, cylinder and cone are carried out in terms of wall effect, re-circulation length and slope of axial velocity profile. The observations revealed the order of CD as cylinder > cone > sphere. The hydrodynamic interactions between wall and fluid medium are presented with the help of velocity contour plots. More asymmetric flow is observed around the particle at higher Reynolds number and for higher wall effect. The simulated results presented herein for unconfined flow are in good agreement with the literature data