In this paper, the stable operation domain of a parametric resonance (PR) based screen machine is thoroughly investigated. The dynamic model of a screen with two di erential equations coupled by a geometric nonlinearity is applied to study the structural motion. In order to address the strong nonlinearities in the equations of motion, the Homotopy Perturbation Method (HPM) is used to compute the longitudinal and transverse oscillations. Since, under excessive excitation, the contact of the vibration screen and loaded materials displays an undesirable vibro-impact response, the HPM is applied under impact and non-impact operation conditions. By considering appropriate technological parameters, including the maximum amplitude desired, spring sti ness, screen mass, initial velocity and acceleration, the best domain of excitation is calculated. The results provide the optimal parameter domain for the new design of a vibrating screen, where the parametric oscillations are excited and the analytically obtained steady oscillation regime is stable. The outcomes of this research respond to changes in the production quality and quantity that are required by customers, and deliver a design guideline for engineers.

Purpose: We aimed to investigate the histopathological correlation of the suspected prostate malignancy detected in multiparametric prostate magnetic resonance imaging (mpMRI). Materials and Methods: The data of 93 patients who underwent radical prostatectomy and had preoperative mp-MRI were examined. Age and pre-operative Prostate-Specific Antigen values were retrospectively collected from patient files. The pathology specimens were examined again and post-operative ISUP grade group, other pathological findings (seminal vesicle invasion, lymph node involvement, and extraprostatic extension), pre-operative mpMRI were re-examined and PIRADS score, extracapsular extension, seminal vesicle invasion, neurovascular bundle invasion, lymph node involvement, and ADC values were recorded. Results: 151 (92, 07%) of 164 lesions detected in mpMRI were histopathologically correlated. 80% of patients with seminal vesicle invasion (P < 0. 001), 28. 8% of patients with extracapsular extension (P < 0. 052) and 42. 9% of patients with lymph node involvement (P =. 001) in mpMRI were histopathologically correlated. A significant relationship was found between PIRADS scores and ISUP grade groups (P < 0. 001). There was a negative correlation between ADC values and ISUP grade groups (P < 0. 001). Conclusion: Our study showed that the lesions detected by mpMRI showed a high histopathological correlation.

Risers are one of the main vessel structural members. So, non-linear vibration analysis of risers, is particularly important. To achieve a proper design, understanding how the transverse vibrations of risers and obtain their frequency response is very useful. In this paper, the transverse vibrations analysis of risers under variable axial load are investigated. The effects of mid-plane stretching is also considered. For this study, the method of multiple time scale is used. In order to verify the accuracy of this method, the results are compared with the results of four order Runge-Kutta numerical method, which has a good accuracy. The frequency response of the system is represented Bifurcation phenomenon. Study of frequency response indicating that there is bifurcation phenomenon in vibrational system, and also the mid-plane stretching of riser will create a hardening behavior. parametric study is also performed that the effect of various parameters is review on the starting point of the bifurcation phenomenon.

Background: The most common cancer (non-cutaneous) malignancy among men is prostate cancer. Management of prostate cancer, including staging and treatment, playing an important role in decreasing mortality rates. Among all current diagnostic tools, multiparametric MRI (mp-MRI) has shown high potential in localizing and staging prostate cancer. Quantification of mp-MRI helps to decrease the dependency of diagnosis on readers’,opinions. Objective: The aim of this research is to set a method based on quantification of mp-MRI images for discrimination between benign and malignant prostatic lesions with fusion-guided MR imaging/transrectal ultrasonography biopsy as a pathology validation reference. Material and Methods: It is an analytical research that 27 patients underwent the mp-MRI examination, including T1-and T2-weighted and diffusion weighted imaging (DWI). Quantification was done by calculating radiomic features from mp-MRI images. Receiver-operating-characteristic curve was done for each feature to evaluate the discriminatory capacity and linear discriminant analysis (LDA) and leave-one-out cross-validation for feature filtering to estimate the sensitivity, specificity and accuracy of the benign and malignant lesion differentiation process is used. Results: An accuracy, sensitivity and specificity of 92. 6%, 95. 2% and 83. 3%, respectively, were achieved from a subset of radiomics features obtained from T2-weighted images and apparent diffusion coefficient (ADC) maps for distinguishing benign and malignant prostate lesions. Conclusion: Quantification of mp-MRI (T2-weighted images and ADC-maps) based on radiomics feature has potential to distinguish benign with appropriate accuracy from malignant prostate lesions. This technique is helpful in preventing needless biopsies in patients and provides an assisted diagnosis for classifications of prostate lesions.