Investigating dimensional and geometrical accuracy of isothermally forged blades

Compressor blades are one of the well-known products made of titanium alloys. They are usually manufactured by a forging process followed by a sequence of machining processes. Precision forging eliminates a considerable amount of machining; however, due to the close tolerances, the process should be designed in a manner to meet dimensional and geometrical tolerances as well as the desired mechanical and metallurgical properties. In this paper, effects of two main process parameters, the process temperature and strain rate, on the dimensional and geometrical accuracy of the isothermally forged blades are investigated experimentally. The results are analyzed by the response surface method (RSM). In order to justify the results and have a tool for further studies, a coupled thermo-mechanical finite element method model is developed and verified by the experimental results. The results show that the process temperature and pressing speed and their interaction have a meaningful effect on the thickness error; however, the interaction effect of the process temperature and pressing speed on the twist error is not considerable and moreover the bow error of the forged blades is not significant. Finally, the results show that for a given geometry, by selection of appropriate process parameters, a sound workpiece with acceptable dimensional and geometrical aspects can be manufactured without any need for a die shape compensation

New Exact Solutions of the Brusselator Reaction Diffusion Model Using the Exp-Function Method

Firstly, using a series of transformations, the Brusselator reaction diffusion model is reduced into a nonlinear reaction diffusion equation, and then through using Exp-function method, more new exact solutions are found which contain soliton solutions. The suggested algorithm is quite efficient and is practically well suited for use in these problems. The results show the reliability and efficiency of the proposed method

Force Eruption of Mandibular Second Incisor in an 11- Year Old Boy: A Technical Report

There is a great challenge in the treatment of deeply fractured and un-restorable teeth among dentists. Orthodontic force eruption is a method of treatment for these teeth to preserve natural root system and periodontal structures. This technical report is a new modification of this procedure presented in an 11- year old boy with deeply fractured left second mandibular incisor. The fractured teeth were treated with root canal therapy and a file #80 was modified to become a hook cemented into the fractured tooth. Anterior teeth were splinted and used as anchorage to help the root extrusion. 1-year follow up of the tooth showed the convenience of the treatment. This simple and low-cost method can be an acceptable alternative to the current high cost techniques, achieving the same results

The Relation between Family Function and Attachment Styles with Social Adjustment of Male and Female High School Students in Bandar Abbas

ABSTRACT This study aimed to investigate relationship between family function and attachment styles with social adjustment of male and female high school students of Bandar Abbas City. Statistical population includes all high school students of Bandar Abbas in 2012-2013 academic year. 376 samples were selected through stratified and multistage sampling methods. Family Assessment Device (Fad), Simpson Attachment Styles (SAS) and Social Attachment questionnaires were employed as research tools. Data analysis indicates that family function and attachment styles micro scales are meaningfully predict students' adjustment. However, separate execution of regression equations among male and female students reveals different results. Relation, emotional education, role playing, general function, emotional companionship and behavior control in females group and family function including emotional education, role playing, general function, problem solving, emotional companionship, and behavior control in males group are among the micro scales that can predict students' adjustment. Every three different attachment styles (secure, ambivalent, insecure) in both male and female groups are predicating meaningfulness of students' adjustment in male and female groups

Effect of heat treatment on optical properties of crosslinkable Azo Chromophore doped in poly amic acid

In this work, we have studied the optical properties of a crosslinkable poly amic acid containing Disperse Red 1. The thin films were cured at 130, 160 and 195 °C. The structural and optical properties of the doped films were investigated by using UV-VIS spectra, and Prism Coupling techniques. The composite crosslinks during poling rendering it totally insoluble. A r33 of 1.5 pm/v was obtained after poling

Developing the attenuation relation for damage spectrum in X-braced steel structures with neural network

Evaluating structural damage, caused by earthquakes, is very important in seismic risk management. Zoning maps of structural damage are directly used in evaluating damage of different zones as well as planning to retrofit structures. Attenuation relation is applied in preparing the acceleration zoning of regions. Similarly, damage attenuation relations which are used in analyzing probabilistic hazard and preparing damage zoning are obtained by structural damage spectrum. This spectrum is nonlinear and designed by considering nonlinear parameters of a series of one-degree-of-freedom structures and time history dynamic analysis. After gathering and modifying 778 records of the earthquakes happened in Iran, the damage spectrum was prepared for X-braced steel structures with different specifications (yield force, hysteresis curves, and ductility capacity). Damage attenuation relation was developed for the structures through regression analysis and the obtained results were compared with those of artificial neural network method. Damage of three samples with different specifications was calculated by the developed attenuation relation. The obtained results were compared with those of time history dynamic analysis. The developed relations were used for analyzing the probabilistic damage risk and preparing the damage zoning maps for city of Qazvin, as a seismic region in Iran

Health-related quality of life and medication adherence in elderly patients with epilepsy

© 2019 Polish Neurological Society. Objective. Considering the high prevalence of epilepsy in the elderly and the importance of maximising their quality of life (QoL), this study aimed to investigate the relationship between medication adherence and QoL, and the mediating effects of medication adherence on the association between serum antiepileptic drug (AED) level and seizure severity with QoL in elderly epileptics. Methods. In a longitudinal study, 766 elderly patients with epilepsy who were prescribed a minimum of one antiepileptic drug were selected by convenience sampling method. A Medication Adherence Report Scale (MARS-5) questionnaire was completed at the baseline. Seizure severity and QoL were assessed after six months using the Liverpool Seizure Severity Scale (LSSS) and the QoL in Epilepsy (QOLIE-31) questionnaires respectively. Serum level of AED was also measured at six-month follow-up. Results. Medication adherence was significantly correlated with both seizure severity (β = -0.33, p < 0.0001) and serum AED level (β = 0.29, p < 0.0001) after adjusting for demographic and clinical characteristics. Neither QoL nor its sub-classes were correlated with seizure severity. In addition, a significant correlation was not observed between serum AED level and QoL. However, medication adherence was significantly correlated with QoL (β = 0.30, p < 0.0001). The mediating effects of medication adherence on the association between serum AED level (Z = 3.39, p < 0.001) and seizure severity (Z = -3.47, p < 0.001) with QoL were supported by the Sobel test. Conclusion. This study demonstrates that medication adherence has a beneficial impact on QoL in elderly epileptics. Therefore, adherence to treatment should be monitored to improve their QoL