Fault diagnosis of main engine journal bearing based on vibration analysis using Fisher linear discriminant, K-nearest neighbor and support vector machine

Vibration technique in a machine condition monitoring provides useful reliable information, bringing significant cost benefits to industry. By comparing the signals of a machine running in normal and faulty conditions, detection of defected journal bearings is possible. This paper presents fault diagnosis of a journal bearing based on vibration analysis using three classifiers: Fisher Linear Discriminant (FLD), K-Nearest Neighbor (KNN) and Support Vector Machine (SVM). The frequency-domain vibration signals of an internal combustion engine with intact and defective main journal bearings were obtained. 30 features were extracted by using statistical and vibration parameters. These features were used as inputs to the classifiers. Two different solution methods - variable K value and RBF kernel width (σ) were applied for FLD, KNN and SVM, respectively, in order to achieve the best accuracy. Finally, performance of the three classifiers was calculated in journal bearing fault diagnosis. The results demonstrated that the performance of SVM was significantly better in comparison to FLD and KNN. Also the results confirmed the potential of this procedure in fault diagnosis of journal bearings

Some Physical Properties of Apple cv. ‘Golab’

Apple is among the popular fruits and of a high economic value. Sorting and grading of apple is needed for the fruit to be presented to local and foreign markets. A study of apple physical properties therefore is imperative. Some physical properties of apples were determined. These properties include: dimensions, mass, volume, surface area, porosity, packaging coefficient and coefficient of static friction. The maximum, average and minimum diameters of apple were 65.04, 53.50 and 35.14 mm respectively. Average volume and mass were 104.5 cm3 and 74.87 g respectively. As for an apple pile, the density and apparent density were respectively calculated as 0.7427 and 0.2401 g/cm3. Maximum, average and minimum porosity of apples were 57.24, 54.13 and 50.17 percent with their sphericity being 1.0028, 0.93 and 0.84 respectively. Average static friction angle of apple on galvanized, glass and plywood surfaces were 20, 26.3 and 26.8 degrees respectively. Average packaging coefficient for the apples studied was 0.45

Mathematical Modeling of Kinetics of Thin-layer Drying of Apple (var. Golab)

Mathematical models of thin-layer drying of apple were studied and verified with experimental data. Fourteen different mathematical drying models were compared according to three statistical parameters, i.e. root mean square error (RMSE), chi-square (X2) and modeling efficiency (EF). The thin-layer drying kinetics of apple slices was experimentally investigated in a laboratory convective dryer and the mathematical modeling, using thin-layer drying models present in the literature, was performed. The main objective of the study was the verification of models already developed. Experiments were performed at air temperature between 40 and 80 °C, velocity of 0.5, 1 and 2 m/s, and thickness of thin layer of 2, 4, 6 mm. Besides the effects of drying air temperature and velocity, effects of slice thickness on the drying characteristics and drying time were also determined. Drying curves obtained from the experimental data were fitted to the-thin layer drying models. The results have shown that, model introduced by Midilli et al. (2002) obtained the highest value of EF = 0.99972, the lowest value of RMSE = 0.00292 and X2 = 10-5. Therefore this model was the best for describing the drying curves of apples. The effects of drying air temperature, velocity and thickness on the drying constant and coefficient were shown to compare the circumstances of drying

Assessing the technical efficiency of energy use in different barberry production systems

The main objectives of this study were to analyze the technical and scale efficiencies of farmers and to identify the wasteful uses of energy in different farm sizes of barberry production in Iran. For these purposes the data envelopment analysis approach was applied to the data of energy use for barberry production in individual farms. The results indicated that total energy input and yield value of small farms were higher than those of large farms. Also, energy resources are used more efficiently in small farms; technical efficiency of farmers in small and large farms was calculated as 0.66 and 0.50, respectively; also, scale efficiency was 0.82 and 0.62 for the respective farms. Total energy input in small and large farms could be reduced by 13.2% and 15.2%, respectively; accordingly, total energy requirement in target conditions was calculated as 20,702.4 and 13,761.2 MJ ha(-1). The highest potential improvement was derived from diesel fuel, followed by electricity and biocides. Improving energy use efficiency of water pumping systems, improving timing, amount and reliability of water application, employing the conservation tillage methods and applying integrated pest management technique are suggested for improving energy use efficiency and reducing the environmental footprints of barberry production. (C) 2012 Elsevier Ltd. All rights reserved

Findings of DTI-p maps in comparison with T 2 /T 2 -FLAIR to assess postoperative hyper-signal abnormal regions in patients with glioblastoma

Abstract Purpose The aim of this study was to compare diffusion tensor imaging (DTI) isotropic map (p-map) with current radiographically (T 2/T 2 -FLAIR) methods based on abnormal hyper-signal size and location of glioblastoma tumor using a semi-automatic approach. Materials and methods Twenty-five patients with biopsy-proved diagnosis of glioblastoma participated in this study. T 2, T 2 -FLAIR images and diffusion tensor imaging (DTI) were acquired 1 week before radiotherapy. Hyper-signal regions on T 2, T 2 -FLAIR and DTI p-map were segmented by means of semi-automated segmentation. Manual segmentation was used as ground truth. Dice Scores (DS) were calculated for validation of semiautomatic method. Discordance Index (DI) and area difference percentage between the three above regions from the three modalities were calculated for each patient. Results Area of abnormality in the p-map was smaller than the corresponding areas in the T 2 and T 2 -FLAIR images in 17 patients; with mean difference percentage of 30 ± 0.15 and 35 ± 0.15, respectively. Abnormal region in the p-map was larger than the corresponding areas in the T 2 -FLAIR and T 2 images in 4 patients; with mean difference percentage of 26 ± 0.17 and 29 ± 0.28, respectively. This region in the p-map was larger than the one in the T 2 image and smaller than the one in the T 2 -FLAIR image in 3 patients; with mean difference percentage of 34 ± 0.08 and 27 ± 0.06, respectively. Lack of concordance was observed ranged from 0.214–0.772 for T 2 -FLAIR/p-map (average: 0.462 ± 0.18), 0.266–0.794 for T 2 /p-map (average: 0.468 ± 0.13) and 0.123–0.776 for T 2 / T 2 -FLAIR (average: 0.423 ± 0.2). These regions on three modalities were segmented using a semi-automatic segmentation method with over 86% sensitivity, 90% specificity and 89% dice score for three modalities. Conclusion It is noted that T 2 , T 2 -FLAIR and DTI p-maps represent different but complementary information for delineation of glioblastoma tumor margins. Therefore, this study suggests DTI p-map modality as a candidate to improve target volume delineation based on conventional modalities, which needs further investigations with follow-up data to be confirmed

Conventional chemoradiation with Cisplatin Versus hemoradiation with Cisplatin plus Gemcitabine in uterine cervical cancer

Background and Objective: Due to high mortality and morbidity of the cervical cancer we decided to compare benefits and advers effects of Gemcitabine plus conventional chemoradiation with conventional chemoradiation with cisplatin alone in Imam Hossein hospital, in Tehran, Iran. Materials and Methods: This double blind clinical trial, was carried out on 34 patients with documented cervical carcinoma during 2006-07 the patients divided into two sub groups: (A)Conventional concurrent chemoradiation with cisplatin(N=18) versus(B) concurrent chemoradiation with cisplatin plus gemicitabine (N=16). The patients with clinical stage of IB2-IVA and normal cell blood count with normal renal and liver function tests included in the study. Irradiation was delivered to all patients through external and internal beams with same dose and schedule. The patients followed for 3 months at least. Clinical response rate and adverse events included Neutropenin, Thrombocytopenia, anemia, diarrhea, nausea, and vomiting compared in two groups with fisher exact test, and t-test. Results: Despite increasing of complete response rate with adding gemcitabine to conventional treatment(81.2% vs. 66.7%), the difference in two groups was not statistically significant. Conclusion: This study indicated that the addition of gemicatabine to conventional chemoradiation with cisplatinrevealed no significant benefits. All adverse events in combination chemotherapy group were greater than conventional treatment