925 research outputs found

    Self Designing Pattern Recognition System Employing Multistage Classification

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    Recently, pattern recognition/classification has received a considerable attention in diverse engineering fields such as biomedical imaging, speaker identification, fingerprint recognition, etc. In most of these applications, it is desirable to maintain the classification accuracy in the presence of corrupted and/or incomplete data. The quality of a given classification technique is measured by the computational complexity, execution time of algorithms, and the number of patterns that can be classified correctly despite any distortion. Some classification techniques that are introduced in the literature are described in Chapter one. In this dissertation, a pattern recognition approach that can be designed to have evolutionary learning by developing the features and selecting the criteria that are best suited for the recognition problem under consideration is proposed. Chapter two presents some of the features used in developing the set of criteria employed by the system to recognize different types of signals. It also presents some of the preprocessing techniques used by the system. The system operates in two modes, namely, the learning (training) mode, and the running mode. In the learning mode, the original and preprocessed signals are projected into different transform domains. The technique automatically tests many criteria over the range of parameters for each criterion. A large number of criteria are developed from the features extracted from these domains. The optimum set of criteria, satisfying specific conditions, is selected. This set of criteria is employed by the system to recognize the original or noisy signals in the running mode. The modes of operation and the classification structures employed by the system are described in details in Chapter three. The proposed pattern recognition system is capable of recognizing an enormously large number of patterns by virtue of the fact that it analyzes the signal in different domains and explores the distinguishing characteristics in each of these domains. In other words, this approach uses available information and extracts more characteristics from the signals, for classification purposes, by projecting the signal in different domains. Some experimental results are given in Chapter four showing the effect of using mathematical transforms in conjunction with preprocessing techniques on the classification accuracy. A comparison between some of the classification approaches, in terms of classification rate in case of distortion, is also given. A sample of experimental implementations is presented in chapter 5 and chapter 6 to illustrate the performance of the proposed pattern recognition system. Preliminary results given confirm the superior performance of the proposed technique relative to the single transform neural network and multi-input neural network approaches for image classification in the presence of additive noise

    Effects of fan inlet temperature disturbances on the stability of a turbofan engine

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    The effects of steady-state and time-dependent fan inlet total temperature disturbances on the stability of a TF30-P-3 turbofan engine were determined. Disturbances were induced by a gaseous-hydrogen-fueled burner system installed upstream of the fan inlet. Data were obtained at a fan inlet Reynolds number index of 0.50 and at a low-pressure-rotor corrected speed of 90 percent of military speed. All tests were conducted with a 90 deg extent of the fan inlet circumference exposed to above-average temperatures

    NASA Lewis F100 engine testing

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    Two builds of an F100 engine model derivative (EMD) engine were evaluated for improvements in engine components and digital electronic engine control (DEEC) logic. Two DEEC flight logics were verified throughout the flight envelope in support of flight clearance for the F100 engine model derivative program (EMPD). A nozzle instability and a faster augmentor transient capability was investigated in support of the F-15 DEEC flight program. Off schedule coupled system mode fan flutter, DEEC nose-boom pressure correlation, DEEC station six pressure comparison, and a new fan inlet variable vane (CIVV) schedule are identified

    Summary of investigations of engine response to distorted inlet conditions

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    A survey is presented of experimental and analytical experience of the NASA Lewis Research Center in engine response to inlet temperature and pressure distortions. This includes a description of the hardware and techniques employed, and a summary of the highlights of experimental investigations and analytical modeling. Distortion devices successfully simulated inlet distortion, and knowledge was gained about compression system response to different types of distortion. A list of NASA research references is included

    Hydrogen Production in the Cyanobacterium Synechocystis sp. PCC 6803 with Engineered Subunit of the Bidirectional H2-ase

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    Hydrogenase (H2-ase) enzyme holds great promise as a bio-generator for bio-solar hydrogen (H2) production. Consequently, an oxygen-tolerant H2-ase is needed in a photosynthetic organism.  In this work, a mutant strain of Synechocystis sp. PCC 6803 with modified H2-ase analyzed under various physiological conditions. The growth rate was higher than that of wt strain and cellular capacity to fix carbon was increased, as shown by higher glycogen accumulation. Oxygen evolution by mutant strain in chemostats was higher than by wt cells over a range of pH levels. The mutant displayed significantly higher hydrogen (H2) production than wt cells, especially at high pH. Examinations of electron flow pathways in the presence of various inhibitors indicated that the genetically modified H2-ase apparently behaves similarly to the wt with respect to its electron source. Remarkably, it was consistently observed H2 production under continuous light conditions, in the presence of oxygen (O2), under many circumstances in both chemostat and batch tests. H2 production in the light was improved under alkaline pH in mutant strain than wt. The data suggest that the genetically modified hydrogenase (H2ase) is a functionally active. Several lines of evidence suggest that O2 may be important in draining electrons from the donor side of photosystem I (PSI) in turn increases the linear electron flow and thereby helping to feed the H2ase activity. In conclusion, the bidirectional H2ase in Synechocystis may play a critical role in cell physiology not only under anoxic conditions but also under O2-evolving activity. Keywords: Cyanobacteria, Hydrogen, Hydrogenase, Protein engineering

    SCIENCE AS A SUBJECT OF LEARNING IN ISLAMIC UNIVERSITY

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    This paper aims to searching theological impact when applied a science as a subject of learning at Agrotechnology Department in the Faculty of Sciences and Technology of State Islamic University of Bandung. The atmospheric experiment was implemented as a subject of learning. By observing the atmospheric data recorded, the plant growth measured significantly affected by the implementation of treatments, the best water supply and fertilizer application. Furthermore, it found that local climate has changed, and Schmidt and Ferguson classification of regional rain types is no more valid, thus, should be renewed. The experiment impacted to a science learning program in Islamic University. Climatic change is a natural law affected by human destructed to the nature. It has been affecting farmers to maintain for their plantation activities. When organisms were effort to surviving in warmer and unpredictable condition, that is shows to human kind has to obligatory to the Almighty God

    Full-scale engine demonstration of an advanced sensor failure detection, isolation and accommodation algorithm: Preliminary results

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    The objective of the advanced detection, isolation, and accommodation (ADIA) program is to improve the overall demonstrated reliability of digital electronic control systems for turbine engines. For this purpose, algorithms were developed which detect, isolate, and accommodate sensor failures using analytical redundancy. Preliminary results of a full scale engine demonstration of the ADIA algorithm are presented. Minimum detectable levels of sensor failures for an F100 turbofan engine control system are determined and compared to those obtained during a previous evaluation of this algorithm using a real-time hybrid computer simulation of the engine

    Science as a Subject of Learning in Islamic University

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    This paper aims to searching theological impact when applied a science as a subject of learning at Agrotechnology Department in the Faculty of Sciences and Technology of State Islamic University of Bandung. The atmospheric experiment was implemented as a subject of learning. By observing the atmospheric data recorded, the plant growth measured significantly affected by the implementation of treatments, the best water supply and fertilizer application. Furthermore, it found that local climate has changed, and Schmidt and Ferguson classification of regional rain types is no more valid, thus, should be renewed. The experiment impacted to a science learning program in Islamic University. Climatic change is a natural law affected by human destructed to the nature. It has been affecting farmers to maintain for their plantation activities. When organisms were effort to surviving in warmer and unpredictable condition, that is shows to human kind has to obligatory to the Almighty God
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