STR-828: BEHAVIOR OF CIRCULAR FRP-REINFORCED CONCRETE COLUMNS UNDER ECCENTRIC LOADING

This paper presents the results of an investigation of the eccentric compression behavior of three full-scale circular concrete columns reinforced with the glass-fiber-reinforced polymer (GFRP) bars and spirals. The column specimens measured 1500 mm height, 305 mm diameter and were tested under monotonic eccentric loading. The main variable was the eccentricity-to-dimeter ratio. Three values were considered in this study (8.20%, 16.39%, and 65.57%). The failure mechanism was changeable according to the level of the applied eccentricity. The failure mechanism of columns at small eccentric loading was defined as compression-controlled due to concrete crushing. At high eccentric loading, the failure of the column cannot simply be characterized by a compression failure, it was rather controlled by the properties of the GFRP bars. The test results were plotted to obtain the experimental P-M interaction diagram. Finally, the experimental results were analyzed and compared with predicted results

Optimum Remedial Operation of Permanent Magnet Synchronous Motor

In critical systems, the reliability of the drive is very important. The faults are unwanted. The faults may be lead to loss of the human life and capital. This paper is addressed this problem and suggested two models to solve it. The first model doesn’t contain any special tools to improve the torque ripple and THD. The second model contains 2PI current controllers to improvement the performance at fault and remedial operation. One is for the torque and the other is for the flux. The first PI controller is feeding from the torque error between the reference and estimated torques to get new q-axis current component representing modifier current arises from uncertain things inside the machine and drive system such as temperature and parameters variations. This current will add to reference q-axis current to get robust new q-axis current to satisfy the drive requirement and solve the torque problem (ripple torque). With robust current, the total harmonic distortion is a decrease but doesn’t reach the best value so the other PI controller is used to adjust the THD. In this PI controller, the d-axis flux is compared to rotor permanent magnet flux to solve this problem arises from non-sinusoidal of the magnetic flux. The output of the PI controller is introduced to the reference d-axis current. The new d-axis current will reach the best value of THD. The simulation of the second controller is compared to the simulation of first controller to show if the second controller strong or weak. Matlab simulink is used to simulate the drive system.DOI:http://dx.doi.org/10.11591/ijece.v2i5.72

STR-824: FATIGUE BEHAVIOR OF CONCRETE UNDERGROUND CHAMBERS REINFORCED WITH GFRP BARS

Precast underground concrete chambers reinforced with steel bars are used frequently in construction and electrical industry for housing power cables and transformers. In Quebec, more than 30,000 of these chambers have been installed by Hydro-Quebec during the last 30 years. However, like other conventionally reinforced concrete structures, corrosion of steel reinforcement constitutes the major cause of chambers deterioration, leading to costly repairs and rehabilitation as well as a significant reduction in service life. This paper presents experimental data on the fatigue and static behavior of full-scale underground concrete chamber reinforced totally with glass fiber-reinforced polymer (GFRP) bars. The chamber measure 2,300 mm in width by 3,800 mm in length and the walls are 2,800 mm high. The chamber was tested under fatigue loading up to one million cycles then test under static load to simulate the traffic load on the manhole. The experimental results were reported in terms of strain and deformation behavior

Association of Helicobacter pylori infection and severity of coronary artery atherosclerosis in patients with suspected coronary artery disease

Background: There is a strong correlation between Helicobacter pylori (HP) infection and coronary artery disease (CAD). There is also a strong correlation between HP infection and the severity of coronary artery atherosclerosis in patients with CAD. Our study determined the association of HP infection and severity of coronary artery atherosclerosis in patients with suspected CAD. Methods: A prospective study of 100 individuals who had coronary angiography for coronary atherosclerosis was conducted. Body mass index (BMI), blood pressure, blood cholesterol, blood glucose, leukocyte count, hemoglobin, and urea breath test were all done on the patients. Coronary angiograms were graded based on vascular and angiographic severity scores. Results: Triglyceride, (TG), Low Density Lipoprotein (LDL), C- Reactive Protein (CRP), Erythrocyte Sedimentation Rate (ESR), vessel score, and angiographic severity score all showed high correlations with Gensini score. There was a substantial association between vessel score and TG, LDL and angiographic severity score. It was found that angiographic severity score has a substantial positive link to a person's BMI; LDL; CRP; ESR, and vessel score. Conclusion: Although HP infection has been linked to an increased risk of coronary artery disease (CAD), established risk variables outweigh their potential impact

STR-827: SHEAR STRENGTH OF CIRCULAR CONCRETE BEAMS REINFORCED WITH GFRP BARS

This paper presents the results of an investigation of the shear strength and behavior of three circular concrete beams reinforced with glass-FRP (GFRP) bars and spirals. The beams, which measured 3,000 mm in length by 500 mm in diameter, were tested under four-point bending. The test parameters included the GFRP-spiral-reinforcement ratio (different spiral spacings [150 and 200 mm] and spiral diameters [13 and 15 mm]). As designed, the beams failed in shear due to GFRP-spiral rupture. The test results indicated that the higher the GFRP spiral reinforcement ratio, the higher the enhancement of the shear strength due to the confinement, which controls shear cracks and improves aggregate interlocking

Evaluation of physical and durability characteristics of new headed glass fiber–reinforced polymer bars for concrete structures

This paper presents the results of a collaborative research project with Quebec’s Ministry of Transportation and the Ontario’s Ministry of Transportation, which aimed at characterizing a new type of headed glass-fiber-reinforced-polymer (GFRP) reinforcing bar and evaluating its suitability as internal reinforcement for concrete structures. To achieve these objectives, the project was implemented in three stages: (1) evaluation of the physical and mechanical properties; (2) determination of the pullout behavior in concrete; and (3) characterization of the long-term durability of the headed GFRP bars. A total of 57 specimens embedded in a 200 mm concrete cube were tested with the direct pullout test to investigate the effect of confinement, bar size, concrete compressive strength, and exposure conditions on the pullout behavior of the headed GFRP bars. Simultaneously, microstructural analyses and measurements of the physicochemical and mechanical properties were carried out on conditioned and unconditioned headed GFRP bars. The results show that the materials, geometry, and interface configuration of the head provided very good mechanical interlocking to the GFRP bars. Up to 63% and 53% of the guaranteed tensile strength of the straight GFRP bars were achieved for 15.9 mm and 19 mm diameter bars with headed ends, respectively. Scanning electron microscopy and differential scanning calorimetry showed no material changes in the head and bars after exposure to alkaline solution and freeze–thaw cycling. Exposure to the alkaline solution under sustained loading had the most detrimental effect, with the bar retaining 79.4% of its pullout strength. The results indicate that the tested headed GFRP bar has suitable mechanical and durability properties for use as reinforcement in concrete bridge components

Arabic open information extraction system using dependency parsing

Arabic is a Semitic language and one of the most natural languages distinguished by the richness in morphological enunciation and derivation. This special and complex nature makes extracting information from the Arabic language difficult and always needs improvement. Open information extraction systems (OIE) have been emerged and used in different languages, especially in English. However, it has almost not been used for the Arabic language. Accordingly, this paper aims to introduce an OIE system that extracts the relation tuple from Arabic web text, exploiting Arabic dependency parsing and thinking carefully about all possible text relations. Based on clause types' propositions as extractable relations and constituents' grammatical functions, the identities of corresponding clause types are established. The proposed system named Arabic open information extraction(AOIE) can extract highly scalable Arabic text relations while being domain independent. Implementing the proposed system handles the problem using supervised strategies while the system relies on unsupervised extraction strategies. Also, the system has been implemented in several domains to avoid information extraction in a specific field. The results prove that the system achieves high efficiency in extracting clauses from large amounts of text

Evaluation of Color Difference and Translucency of Modified PEEK Restorations Veneered with Different Veneering Materials Before and After Thermal Cycling

Objective: The aim of this study was to investigate the effect of different PEEK veneering materials, as well as thermocycling on the color difference (ΔE) and the translucency parameter (TP) of modified PEEK veneered restorations. Materials and Methods: Thirty disc shaped specimens of veneered BioHPP (1.5 mm X 12 mm) were randomly divided into three groups (n=10) based on the type of the veneering material. Group (A): Discs veneered with CAD milled Lithium Disilicate, group (B): Discs veneered with pre-cured milled composite, and group (C): Discs veneered with conventional light cured composite. CIELab values were calculated for all specimens over white and black backgrounds using a laboratory spectrophotometer and then (ΔE) and (TP) were calculated. Specimens were subjected to thermal cycling, after which the same procedure for calculating (ΔE) and (TP) was repeated. Results: Repeated measures ANOVA showed that both the veneering material, and thermocycling had a statistically significant effect on mean ΔE, and on (TP) (P-value Conclusions: All veneering techniques rendered an amount of color difference that was clinically unacceptable, as well as displaying much lower translucency levels than that of natural enamel and dentine