Compact Bandpass Filters Using Dual-Mode Microstrip Closed-Loop Ring Resonators for Wireless Communication Systems

Microwave filters have important role in many wireless and communication systems such as satellite and cellular mobile organizations. In such kind of systems, factors such as compact size, low cost, light weight, high performance, and low loss in designing of microwave filters are of primary importance. In comparison with waveguide filters, microstrip filters are smaller and in such applications mentioned before there are needs to have smaller microstrip filters. In this thesis, filters using dual-mode ring resonators is proposed, because they can be designed easier than the other kind of microwave filters and are more compact. In this thesis, a new compact form of dual-mode microstrip octagonal loop resonator filter is proposed in two forms; conventional and compact. These structures are designed to operate at WiMax frequency of 2.3 GHz with a 5% fractional bandwidth. The new dual-mode resonator will be produced by adding a rectangular patch inside the loop resonator. The experimental results and simulated values are presented and show good agreement. The filter is fabricated on CER-10 substrate having a relative dielectric constant of 10 and 0.64 mm thickness. The primary dimension of the filter is 15.8 mm´15.8 mm and the measured minimum insertion loss is 1.68 dB and return loss is better than -20 dB. After minimization and compressing the filter structure, the final dimension is reduced to 9.1 mm´9.1 mm. The minimum insertion loss in this structure is 1.52 dB and the return loss is better than -20 dB. In the final design in addition to size reduction (about 42%), feed lines structure is changed from orthogonal to straight line form, which are more desirable in microwave networks. This new design is reduced in size by approximately 25% compared to the conventional square loop dual-mode filter. By using meander square loop structure more reduction in size (about 27%) can be achieved but this filter configuration has a weak frequency response including high passband insertion loss (more than 2.6 dB) and return loss less than -12dB at the same center frequency. Therefore its performance is less than the dual-mode filter proposed in this thesis. Apart from WiMax, this model of filters is also useful for WLAN and mobile communication applications, because it is compact in size, low loss and has good performance due to its elliptic response with sharp rejection and adequate fractional bandwidth

Income inequality and intergenerational transmission of wealth.

openThis paper reviews various aspects of income inequality and wealth transmission, highlighting the multifaceted nature of these phenomena. It emphasizes the pivotal role of education as a potential tool for breaking the cycle of inequality and promoting intergenerational economic mobility. Policy interventions, such as equitable access to education and support for lifelong learning, can play a crucial role in addressing income inequality and fostering a more inclusive and prosperous society

Idiopathic Submitral Left Ventricular Aneurysm: an Unusual Substrate for Ventricular Tachycardia in Caucasians

Annular submitral aneurysms have been rarely reported in Caucasians. They are typically diagnosed in non-white adults who present with severe mitral regurgitation, heart failure, systemic embolism, ventricular arrhythmias, and sudden cardiac death. In this article, we describe the case of a white woman, presenting with ventricular tachycardia, who had a large submitral left ventricular aneurysm diagnosed incidentally during coronary angiography

Abnormal heart rate recovery after exercise predicts coronary artery disease severity

Background: Slow heart rate recovery (HRR) after exercise is considered to represent impaired parasympathetic tone and to be a predictor of all-cause and cardiovascular mortality, but the independent value of abnormal HRR in predicting the presence and severity of coronary artery disease (CAD) is unknown. The aim of this study was to evaluate these relationships in our patients. Methods: This prospective cross-sectional study included 208 patients (67.3% men), aged 34 to 74 (mean 53) years. Patients who had an ischemic response during symptom-limited exercise testing underwent selective coronary angiography. The value for HRR was defined as the decrease in heart rate from peak exercise to one minute after the exercise ceased. Eighteen beats per minute was defined as the lowest normal value for HRR. Results: Significant CAD was detected in 140 (67.3%) patients. There were 66 (31.7%) patients with an abnormal HRR. In multivariable logistic regression analysis adjusted for established CAD risk factors, abnormal HRR was independently correlated with the extent of major epicardial coronary involvement (p = 0.04). The sensitivity, specificity, positive and negative predictive values, and accuracy of abnormal HRR for predicting extensive CAD were 48%, 83.3%, 72.7%, and 63.4%, respectively. There was also a significant correlation between HRR one minute after exercise and smoking (p = 0.004), chronotropic variables (p = 0.001), and the calculated risk score for the exercise test (p = 0.03). There was no significant correlation between HRR and other risk factors including age and gender, left ventricular systolic function, and history of myocardial infarction. Conclusions: There is a significant correlation between abnormal post-exercise HRR at one minute and the extent of major epicardial coronary involvement. (Cardiol J 2011; 18, 1: 47-54

Un modelo de banca universal basado en el empoderamiento y el desarrollo de habilidades

The present paper aims to propose a universal banking system focusing on the empowerment and skill development of bank employees. This study used the Delphi fuzzy method to select experts and classify and analyze their responses. Further, the DEMATEL method was used to identify and investigate the criteria correlations and map the network relationships. A robust statistical method was used to solve optimization problems based on data uncertainty. The results drawn from the model indicated that factors such as employee decision-making ability, responsibility towards executing a decision, access to decision tools, and employee self-efficacy sources influence the empowerment of employees and correct implementation of private, corporate, business, and investment banking. Further, they showed that sense of competence, motivation, participation, sense of effectiveness, and information technology influence universal banking. In addition, training and reward influence all types of universal banking.El presente documento tiene como objetivo proponer un sistema bancario universal centrado en el empoderamiento y el desarrollo de habilidades de los empleados bancarios. Este estudio utilizó el método difuso Delphi para seleccionar expertos y clasificar y analizar sus respuestas. Además, el método DEMATEL se utilizó para identificar e investigar las correlaciones de criterios y mapear las relaciones de red. Se utilizó un método estadístico robusto para resolver problemas de optimización basados ​​en la incertidumbre de los datos. Los resultados extraídos del modelo indicaron que factores tales como la capacidad de toma de decisiones de los empleados, la responsabilidad de ejecutar una decisión, el acceso a las herramientas de decisión y las fuentes de autoeficacia de los empleados influyen en el empoderamiento de los empleados y la correcta implementación de empresas privadas, corporativas y comerciales. banca de inversión. Además, mostraron que el sentido de competencia, motivación, participación, sentido de efectividad y tecnología de la información influyen en la banca universal. Además, la capacitación y la recompensa influyen en todos los tipos de banca universal

Narrowband elliptic bandpass filter using dual-mode microstrip square loop resonator for WiMax application

In this paper, a narrowband bandpass filter using dual-mode microstrip square loop resonator is proposed. This structure has a 5.1% fractional bandwidth at 2.3GHz. By using some simple techniques, the optimum results will be achieved. The dual-mode resonator will be produced by adding a square patch inside the loop resonator. The simulation and measurement results are also presented. The filter is fabricated on RT/Duroid 6010 substrate having a relative dielectric constant of 10.2 and 0.635 mm thickness. The final dimension is measured at 19.65 mm 19.65 mm. The minimum measured insertion loss is 1.68 dB and return loss obtained is better than -20 dB, where experimental results and simulated values are in good agreement

Promotional effect of nitric acid treatment on CO sensing properties of SnO2/MWCNT nanocomposites

In this paper, SnO2/MWCNT nanocomposites with different types of MWCNTs, namely as-received, acid treated and Ag-decorated, were synthesized via a facile method and their CO gas sensing properties were investigated. Microstructure and phase formation of the synthesized composites were studied using FE-SEM and XRD, respectively. Fourier transform infrared spectroscopy (FTIR) was employed to study the functional groups on the surface of MWCNTs after acid treatment. CO gas sensing results showed that the samples containing 0.8 wt.% MWCNT with 2 h acid treatment by HNO3 have the best response to CO gas

Idiopathic Submitral Left Ventricular Aneurysm: an unusual substrate for ventricular tachycardia in Caucasians

Annular submitral aneurysms have been rarely reported in Caucasians. They are typically diagnosed in non-white adults who present with severe mitral regurgitation, heart failure, systemic embolism, ventricular arrhythmias, and sudden cardiac death. In this article, we describe the case of a white woman, presenting with ventricular tachycardia, who had a large submitral left ventricular aneurysm diagnosed incidentally during coronary angiography

Habitat suitability and modelling the potential distribution of the Plateau Snake Skink Ophiomorus nuchalis (Sauria Scincidae) on the Iranian Plateau

Species distribution models estimate the relationship between species occurrences and environmental and spatial characteristics. Herein, we used maximum entropy distribution modelling (MaxEnt) for predicting the potential distribution of the Plateau Snake Skink Ophiomorus nuchalis on the Iranian Plateau, using a small number of occurrence records (i.e. 10) and environmental variables derived from remote sensing. The MaxEnt model had a high success rate according to test AUC scores (0.912). A remotely sensed enhanced vegetation index (39.1%), and precipitation of the driest month (15.4%) were the most important environmental variables that explained the geographical distribution of O. nuchalis. Our results are congruent with previous studies suggesting that suitable habitat of O. nuchalis is limited to the central Iranian Plateau, although mountain ranges in western and eastern Iran might be environmentally suitable but not accessible.Peer reviewe

A comparison of artificial intelligence algorithms in diagnosing and predicting gastric cancer: a review study

Today, artificial intelligence is considered a powerful tool that can help physicians identify and diagnose and predict diseases. Gastric cancer has been the fourth most common malignancy and the second leading cause of cancer mortality in the world. Thus, timely diagnosis of this type of cancer could effectively control it. This paper compares AI (artificial intelligence) algorithms in diagnosing and predicting gastric cancer based on types of AI algorithms, sample size, accuracy, sensitivity, and specificity.  This narrative-review paper aims to explore AI algorithms in diagnosing and predicting gastric cancer. To achieve this goal, we reviewed English articles published between 2011 and 2021 in PubMed and Science direct databases. According to the reviews conducted on the published papers, the endoscopic method has been the most used method to collect and incorporate samples into designed models. Also, the SVM (support vector machine), convolutional neural network (CNN), and deep-type CNN have been used the most; therefore, we propose the usage of these algorithms in medical subjects, especially in gastric cancer