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111.
Chinmay Rao Asok Ray Soumik Sarkar Murat Yasar 《Signal, Image and Video Processing》2009,3(2):101-114
Symbolic dynamic filtering (SDF) has been recently reported in literature as a pattern recognition tool for early detection
of anomalies (i.e., deviations from the nominal behavior) in complex dynamical systems. This paper presents a review of SDF
and its performance evaluation relative to other classes of pattern recognition tools, such as Bayesian Filters and Artificial
Neural Networks, from the perspectives of: (i) anomaly detection capability, (ii) decision making for failure mitigation and
(iii) computational efficiency. The evaluation is based on analysis of time series data generated from a nonlinear active
electronic system.
This work has been supported in part by the U.S. Army Research Laboratory and the U.S. Army Research Office under Grant No.
W911NF-07-1-0376, by the U.S. Office of Naval Research under Grant No. N00014-08-1-380, and by NASA under Cooperative Agreement
No. NNX07AK49A. 相似文献
112.
Abdulselam Ertas Mustafa Abdullah Yilmaz Mehmet Boga Nesrin Hasimi Yeter Yesil Ahmet C. Goren 《International Journal of Food Properties》2016,19(1):124-138
The objectives of this study were to define the phenolic and fatty acid profiles, anticholinesterase, antioxidant, antimicrobial activities, and total phenolic-flavonoid contents of Lycopsis orientalis and Tragopogon latifolius var. angustifolius which have been used as food source and food supplement in Anatolia and have never been examined before. Rosmarinic and quinic acids (21.11 and 11.46 mg g–1 extract, respectively) were found to be the most abundant constituents in L. orientalis and T. latifolius var. angustifolius among the studied 27 compounds by liquid chromatography tandem mass spectrometry. In the fatty acid compositions of L. orientalis and T. latifolius var. angustifolius that were determined by gas chromatography mass spectrometry, oleic (29.1%) and palmitic (28.7%) acids were identified as the major components, respectively. The high antioxidant activity of the methanol extract of L. orientalis shows parallelism to its rosmarinic acid content. Besides, this extract showed medium anticholinesterase activity. The results of the present study proves that the L. orientalis might also be used as a food source due to its high phenolic acid content and strong antioxidant property. 相似文献
113.
A constrained model predictive control (MPC) is designed to regulate the air flow rate of proton exchange membrane fuel cell (PEMFC). Oxygen excess ratio, compressor flow rate and supply manifold pressure are constrained to avoid oxygen starvation, surge and choke phenomena. This is achieved by manipulating compressor voltage and stack current. The choice of the manipulated input to satisfy a constraint is investigated. Surge and choke avoidance is successful, when compressor voltage is manipulated. When stack current is utilized to satisfy surge and choke constraints, a large unrealistic current is needed. Oxygen starvation is successfully avoided utilizing stack current, while compressor voltage manipulation fails to prevent oxygen starvation. Thus, a current governor is implemented to handle oxygen starvation, while the compressor voltage is constrained to avoid surge and choke. Quadratic programming optimization, Laguerre and exponential weight function are employed to reduce the computational burden of the controller. The simulation results prove that the proposed controller managed to satisfy all constraints without any conflict. 相似文献
114.
115.
The authors developed a two-dimensional one-temperature chemical non-equilibrium (1T-NCE) model of Ar-CO2-H2 inductively coupled thermal plasmas (ICTP) to investigate the effect of pressure variation. The basic concept of one-temperature model is the assumption and treatment of the same energy conservation equation for electrons and heavy particles. The energy conservation equations consider reaction heat effects and energy transfer among the species produced as well as enthalpy flow resulting from diffusion. Assuming twenty two (22) different particles in this model and by solving mass conservation equations for each particle, considering diffusion, convection and net production terms resulting from hundred and ninety eight (198) chemical reactions, chemical non-equilibrium effects were taken into account. Transport and thermodynamic properties of Ar-CO2-H2 thermal plasmas were self-consistently calculated using the first-order approximation of the Chapman-Enskog method. Finally results obtained at atmospheric pressure (760 Torr) and at reduced pressure (500, 300 Torr) were compared with results from one-temperature chemical equilibrium (1T-CE) model. And of course, this comparison supported discussion of chemical non-equilibrium effects in the inductively coupled thermal plasmas (ICTP). 相似文献
116.
Yasar Islamoglu 《传热工程》2013,34(4):073-076
Abstract In the present study, the ability of an artificial neural network model to evaluate the thermal performance of a cooling tower, which used in the heating, ventilating, and air conditioning industries to reject heat to the atmosphere, is examined. The network is trained with the following experimental values: the ratio of the water mass flow rate to air mass flow rate, the inlet water temperature, and the outlet water temperature, and the inlet air wet-bulb temperature are selected as input variables, while the output is the coefficient of performance. It is concluded that a well-trained neural network provides fast, accurate, and consistent results, making it an easy-to use tool for preliminary engineering studies. 相似文献
117.
This paper is concerned with the energy and exergy analyses of the thin layer drying process of mulberry via forced solar dryer. Using the first law of thermodynamics, energy analysis was carried out to estimate the ratios of energy utilization and the amounts of energy gain from the solar air collector. However, exergy analysis was accomplished to determine exergy losses during the drying process by applying the second law of thermodynamics. The drying experiments were conducted at different five drying mass flow rate varied between 0.014 kg/s and 0.036 kg/s. The effects of inlet air velocity and drying time on both energy and exergy were studied. The main values of energy utilization ratio were found to be as 55.2%, 32.19%, 29.2%, 21.5% and 20.5% for the five different drying mass flow rate ranged between 0.014 kg/s and 0.036 kg/s. The main values of exergy loss were found to be as 10.82 W, 6.41 W, 4.92 W, 4.06 W and 2.65 W with the drying mass flow rate varied between 0.014 kg/s and 0.036 kg/s. It was concluded that both energy utilization ratio and exergy loss decreased with increasing drying mass flow rate while the exergetic efficiency increased. 相似文献
118.
Hairus Abdullah Noto Susanto Gultom Dong-Hau Kuo 《Journal of Materials Science》2017,52(11):6249-6264
Indium oxysulfide nanosheet (In2(O,S)3 NS) had been successfully synthesized by a solution-based process at 90 °C. To further study some properties of photocatalyst, the 90 °C-prepared In2(O,S)3 NS was annealed at 350, 400, and 450 °C in air for 2 h. It was found that the nanosheet structure at 90 °C changed to nanoparticle at higher temperature. All the as-prepared and annealed photocatalysts were carefully characterized and examined toward photocatalytic hexavalent chromium (Cr(VI)) reduction. Among the photocatalysts, 90 °C-prepared In2(O,S)3 NS exhibited the greatest photocatalytic reduction of Cr(VI) without using any hole scavenger reagent under 150 W visible light illumination. After the Ag deposition on In2(O,S)3 NS, the photocatalyst could produce nearly 400 μmol/g hydrogen gas in ethanol solution under 150 W Xe-lamp irradiation for 5 h. The great performance of 90 °C-prepared In2(O,S)3 NS was due to the high surface area of nanosheet morphology and the formation of solid solution which significantly increased the visible light absorbance. The photocatalytic activities and their mechanisms of 90 °C-prepared In2(O,S)3 NS were evaluated and elaborated in this work. 相似文献
119.
C.Y. Khor M.Z. Abdullah M. Abdul Mujeebu F. Che Ani 《International Communications in Heat and Mass Transfer》2010
In this paper, the finite volume method (FVM) based numerical simulation is used for the flow visualization of capillary driven underfill process for different solder bump arrangements of flip chip packages is presented. Three different 3D flip chip package models are developed and simulated using computational fluid dynamic (CFD) code, FLUENT 6.3. Capillary action and cross viscosity model are taken into account in the simulation. One-line dispensing method is applied in the analysis and the volume of fluid (VOF) technique is used to track the flow front. The effect of solder balls arrangement on flow behavior and filling time is studied and the solder balls arrangement is found to affect the flow behavior and filling time. The flow patterns of simulation are observed for three flip chip packages and compared. The ability of the proposed model and FLUENT in handling flip chip underfill problems is proved to be excellent. 相似文献
120.
Muha Abdullah Al Pavel Masud Abdullah Chowdhury 《The International journal of environmental studies》2013,70(3):261-269
This paper offers an economic evaluation of the floating garden as a means of adapting to climate change in Bangladesh. The study showed that the monthly income of some farmers using such gardens increased from US$12.02 to US$48.08. These folk farmers lacked alternative work especially during the monsoon period. The floating garden uses available natural resources, adjusts to wet conditions and helps the flood-prone people to earn a living, and can be an adaptive response to frequent disaster events in Bangladesh. 相似文献