1,412 research outputs found
Depth estimation of inner wall defects by means of infrared thermography
There two common methods dealing with interpreting data from infrared thermography: qualitatively and quantitatively. On a certain condition, the first method would be sufficient, but for an accurate interpretation, one should undergo the second one. This report proposes a method to estimate the defect depth quantitatively at an inner wall of petrochemical furnace wall. Finite element method (FEM) is used to model multilayer walls and to simulate temperature distribution due to the existence of the defect. Five informative parameters are proposed for depth estimation purpose. These parameters are the maximum temperature over the defect area (Tmax-def), the average temperature at the right edge of the defect (Tavg-right), the average temperature at the left edge of the defect (Tavg-left), the average temperature at the top edge of the defect (Tavg-top), and the average temperature over the sound area (Tavg-so). Artificial Neural Network (ANN) was trained with these parameters for estimating the defect depth. Two ANN architectures, Multi Layer Perceptron (MLP) and Radial Basis Function (RBF) network were trained for various defect depths. ANNs were used to estimate the controlled and testing data. The result shows that 100% accuracy of depth estimation was achieved for the controlled data. For the testing data, the accuracy was above 90% for the MLP network and above 80% for the RBF network. The results showed that the proposed informative parameters are useful for the estimation of defect depth and it is also clear that ANN can be used for quantitative interpretation of thermography data
Adaptive thresholding in dynamic scene analysis for extraction of fine line
This paper presents an adaptive threshold method whereby a fine thin line of one-pixel width lines could be detected in a gray level images. The proposed method uses the percentage difference between the mean of the pixels within a window and the center pixel. The minimum threshold value however is heuristically set to 32. If the percentage difference is greater than 40% then the threshold value will be set to the difference value. This method has been applied in detecting moving objects with fine lines and the results showed that the method was able to pickup straight thin edges that belong to the moving objec
Exploring Psychological Well-Being Among Tahfiz Al-Quran Students: Emprical Study Using Psychoeducation Counseling and Therapy
This study aims to explore mental stress, self-efficacy and coping strategies that contribute to the stability of tahfiz students' mental health. This study is a qualitative study that uses phenomenological methods in psychoeducational group counseling. The respondents of this study consisted of 5 students of Tahfiz School and Malaysian Armed Forces Orphans (STAY ATM) who were 17 years old. Data analysis using content analysis techniques. The results of the study found that the mental stress faced by tahfiz students is caused by parental coercion, military- lifestyle and environmental factors. As a result of the mental stress experienced, emotional changes also occur. In the aspect of self-efficacy, tahfiz students have personal advantages such as being talented in various fields, extroverted, and independent, but their introvert attitude, low self-esteem and not knowing how to manage time are also their weaknesses. From the aspect of coping strategies, tahfiz students have a mature and rational coping strategy in managing the mental stress they face and have a clear future plan. Al Quran approach clearly shows that it can have a positive effect on the mental stability of tahfiz students. The results of this study have positive implications for students, parents, STAY ATM’s and community
A review on chemical diagnosis techniques for transformer paper insulation degradation
Energized parts within power transformer are isolated using paper insulation and are immersed in insulating oil. Hence, transformer oil and paper insulation are essential sources to detect incipient and fast developing power transformer faults. Several chemical diagnoses techniques are developed to examine the condition of paper insulation such as degree of polymerization, carbon oxides, furanic compounds and methanol. The principle and limitation of these diagnoses are discussed and compared in this paper
ELECTRICITY SAVINGS BY IMPLEMENTING ENERGY EFFICIENCY STANDARDS AND LABELS FOR CLOTHES WASHERS IN MALAYSIA
Clothes washers being one of the energy consuming household appliances in Malaysia have become a target for energy efficiency improvements. In the present study, a series of experiment investigations have been conducted on six clothes washers of varying capacities. The objectives are to develop the standards and labels. The test has been performed according to IEC (International Electrotechnical Commision) clothes washers test specification. Using the experimental data, a baseline standard has been developed by statistical method. From the baseline standards, 10% standards have been developed. The baseline unit energy consumption was calculated to be 32 Wh/kg/cycle (average unit energy consumption of the six models) and on the basis of baseline unit, standard unit energy consumption had been proposed to be 29 Wh/kg/cycle. It has been estimated with the introduction of minimum energy efficiency standards for clothes washer 38077037.46 kWh of energy could be saved per year. To develop a comprehensive energy guide labels, three labels had been design, which were star labeling, speedometer labeling and letter bin labeling. A survey was conducted with three different types of labels among the consumers and with the surveys respond, energy guide label of household clothes washers has been proposed for Malaysia. This is result from used of energy-efficient appliances product and is well positioned to promote more widespread efficient improvement
Superconducting magnetic energy storage unit, an efficient energy technology for power systems
This paper discusses application of superconducting magnetic energy storage (SMES) unit to improve power system performance. The application of SMES unit in mitigating voltage sags and in damping dynamic oscillations in power systems is discussed. To show the effectiveness of the proposed controller in providing continuous voltage regulation and in enhancing power system dynamics, a three-phase short circuit is applied to the system and simulation is carried out with and with no SMES connected to the system. The results of these investigations are studied using the well-developed graphic facilities available in an industry standard power system package, namely PSCAD/EMTDC. Results have shown that SMES unit can effectively improve system stability and power quality of power systems
High frequency transformer computer modeling
Frequency response analysis (FRA) technique is nowadays widely used in both factory and field applications as a diagnostic tool for power transformers. The main problem about FRA techniques is to interpret the observed evolution of the frequency response in order to identify failures. Transformer high frequency computer modeling is proposed in this work to be used with the FRA. The physical meaning of the model parameters allows the identification of the problem inside the transformer. The paper presents the model and experimental results and analysis of the frequency responses on the variations of the winding parameters. Effect of core, bushings, oil and tank on FRA is also investigated
Fingerprint center point location using directional field
This paper presents a reliable fingerprint center point (CP) location algorithm for the alignment of fingerprints to construct a shift invariant fingerprint recognition system. The proposed algorithm is based on Alteration Tracking (AT) and CP estimation (CPE). AT is proposed to extract a track that records the transition from one quantized direction to another. CPE is aimed to find the bending point with highest transition of direction from the transition track. This algorithm is tested against fingerprints captured from SAGEM MSO100 optical scanner and the second database from University of Bologna. Experimental result shows that the proposed algorithm is capable of reliably locating fingerprint CP
Characterizations on microencapsulated sunflower oil as self-healing agent using In situ polymerization method
This paper emphasizes the characterization on the microencapsulation of sunflower oil as self-healing agent. In-situ polymerization method mainly implicates in the microencapsulation
process. The analysis of microencapsulated sunflower oil via prominent characterization of yield of microcapsules, microcapsules characteristics and Fourier Transmission Infa-Red Spectroscopy (FTIR). The prime optimization used was reaction time of microencapsulation process in the ranges of 2, 3 and 4 h. The higher reaction time of microencapsulation process resulted in a higher yield of microcapsules. The yield of microcapsules increases from 46 to 53% respectively by the increasing of reaction time from 2 to 4 h. The surface morphology study associating the diameter of microcapsules measured to analyse the prepared microcapsules. It was indicated that microcapsules were round in shape with smooth micro-surfaces. It was discovered that the diameter of microcapsules during microencapsulation process after 4 h reaction time was in average of
70.53 μm. This size was measured before filtering the microcapsules with solvent and dried in vacuum oven. Apparently, after filtering and drying stage, the diameter of microcapsules specifically identified under Field Emission Scanning Electron Microscopy (FESEM) showing the size of 2.33 μm may be due to the removing the suspended oil surrounded the microcapsules. Sunflower oil as core content and urea formaldehyde (UF) as shell of microcapsules demonstrated the proven chemical properties on characterization by FTIR with the stretching peak of 1537.99 - 1538.90 cm-1 (-H in -CH2), 1235.49 - 1238.77 cm-1 (C-O-C Vibrations at Ester) and 1017.65 - 1034.11 cm-1 (C-OH Stretching Vibrations). It was showed that sunflower oil can be considered as an alternative nature resource for self-healing agent in microencapsulation process. The characterization of microencapsulated sunflower oil using in-situ polymerization method showed that sunflower oil was viable self-healing agent to be encapsulated and incorporated in metal coating
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