Weigh-in-Motion load effects and statistical approaches for development of live load factors

Arcan Yanik,Christopher Higgins 국제구조공학회 2020 Structural Engineering and Mechanics, An Int'l Jou Vol.76 No.1

The aim of this paper is to simply present live load factor calculation methodology formulation with the addition of a simple new future load projection procedure to previously proposed two methods. For this purpose, Oregon Weigh-in-Motion (WIM) data were used to calculate live load factors by using WIM data. These factors were calculated with two different approaches and by presenting new simple modifications in these methods. A very simple future load projection method is presented in this paper. Using four different WIM sites with different average daily truck traffic (ADTT) volume, and all year data, live load factors were obtained. The live load factors, were proposed as a function of ADTT. ADTT values of these sites correspond to three different levels which are approximately ADTT= 5,000, ADTT = 1,500 and ADTT ≤ 500 cases. WIM data for a full year were used from each site in the calibration procedure. Load effects were projected into the future for the different span lengths considering five-year evaluation period and seventy-five-years design life. The live load factor for ADTT=5,000, AASHTO HS20 loading case and five-year evaluation period was obtained as 1.8. In the second approach, the methodology established in the Manual for Bridge Evaluation (MBE) was used to calibrate the live load factors. It was obtained that the calculated live load factors were smaller than those in the MBE specifications, and smaller than those used in the initial calibration which did not convert to the gross vehicle weight (GVW) into truck type 3S2 defined by AASHTO equivalents.

A Discrete-Time Nonlinear Robust Controller for Current Regulation in PMSM Drives

Turker, Turker,Yanik, Gurcan,Buyukkeles, Umit,Bakan, Faruk,Mese, Erkan The Korean Institute of Electrical Engineers 2017 Journal of Electrical Engineering & Technology Vol.8 No.1

In this paper, a discrete-time robust current controller is proposed for PMSM drives. The structure of the proposed controller is quite simple and does not require high computational resource. The only difference of the proposed controller from the classical dead-beat controller is the integral term which can easily be implemented in a PMSM drive. The stability analysis of the proposed controller is performed accounting in parametric uncertainties, unmodelled dynamics and disturbances in the mathematical model. The boundedness of the dynamical system and asymptotic convergence of dq-axes currents to their reference values are provided under certain conditions. Various simulation and experimental studies are performed and the results taken at different operation conditions show the validity of the proposed controller.

A Discrete-Time Nonlinear Robust Controller for Current Regulation in PMSM Drives

Turker Turker,Gurcan Yanik,Umit Buyukkeles,Faruk Bakan,Erkan Mese 대한전기학회 2017 Journal of Electrical Engineering & Technology Vol.12 No.4

In this paper, a discrete-time robust current controller is proposed for PMSM drives. The structure of the proposed controller is quite simple and does not require high computational resource. The only difference of the proposed controller from the classical dead-beat controller is the integral term which can easily be implemented in a PMSM drive. The stability analysis of the proposed controller is performed accounting in parametric uncertainties, unmodelled dynamics and disturbances in the mathematical model. The boundedness of the dynamical system and asymptotic convergence of dq-axes currents to their reference values are provided under certain conditions. Various simulation and experimental studies are performed and the results taken at different operation conditions show the validity of the proposed controller.

Morphometric Evaluation of Bony Nasolacrimal Canal in a Caucasian Population with Primary Acquired Nasolacrimal Duct Obstruction: A Multidetector Computed Tomography Study

Erdogan Bulbul,Alper Yazici,Bahar Yanik,Hasmet Yazici,Gulen Demirpolat 대한영상의학회 2016 Korean Journal of Radiology Vol.17 No.2

Objective: The bony nasolacrimal duct (BNLD) morphology as a contributory factor in primary acquired nasolacrimal duct obstruction (PANDO) is still controversial. The objectives of this study were to evaluate the morphometric differences of BNLDs in unilateral PANDO patients between PANDO and non-PANDO sides, as compared with the control group using multidetector computed tomography (CT). Materials and Methods: Bilateral BNLDs in 39 unilateral PANDO patients and 36 control subjects were retrospectively reviewed. CT images with 0.5-mm thickness were obtained with a 64-slice scanner. The length, volume, coronal orientation type, sagittal orientation angle of BNLD, and relative lacrimal sac-BNLD angle were assessed. The entrance, minimum and distal end transverse diameters (TD) of BNLD was investigated. Results: The mean minimum and distal end BNLD TDs measurements were significantly narrower in PANDO patients, both in PANDO and non-PANDO sides, as compared with the control group (p < 0.001 and p = 0.040, respectively); however, there were no significant differences between PANDO and non-PANDO sides within PANDO patients. The length, entrance TD, volume, coronal orientation type, sagittal orientation angle of BNLD, and relative lacrimal sac-BNLD angle were not significantly different between PANDO patients and control subjects, as well as between PANDO and non-PANDO sides within PANDO patients. Conclusion: The narrow mean minimum and distal end BNLD TD in PANDO patients, in both PANDO and non-PANDO sides, may be associated with PANDO development. The lack of difference between PANDO and non-PANDO sides within PANDO patients and some overlap between PANDO patients and control subjects suggest that narrow BNLD is not the sole factor.

Intraspinal Anomalies in Individuals with Scheuermann’s Kyphosis: Is the Routine Use of Magnetic Resonance Imaging Necessary for Preoperative Evaluation?

Serdar Demiroz,Ismail Emre Ketenci,Hakan Serhat Yanik,Samet Bayram,Koray Ur,Sevki Erdem 대한척추외과학회 2018 Asian Spine Journal Vol.12 No.4

Study Design: Retrospective study. Purpose: This study aimed to determine the incidence of intraspinal pathologies (ISPs) in individuals with Scheuermann’s kyphosis (SK) and to validate whether the routine use of magnetic resonance imaging (MRI) is necessary for preoperative evaluation. Overview of Literature: There are several studies on the necessity of routine MRI screening and prevalence of ISPs related to different types of scoliosis have been conducted. However, despite the well-established association between ISPs and a higher risk for neurological complications there is no any study on the scientific literature concerning the prevalence of ISPs in patients with SK has been conducted. Methods: The database of the institution was retrospectively reviewed to identify all patients diagnosed with SK who underwent surgery between 2012 and 2015. Patients were excluded from the study if their hospital database records did not include spinal images, which are routinely collected before surgery. The presence or absence of ISPs, as indicated on magnetic resonance images, was evaluated by a radiologist. Results: Of the 138 potential participants, 120 were included in the study. Of these, seven patients (5.8%) had ISPs, and all the cases involved syringomyelia. None of the seven patients with ISPs required additional neurosurgical procedures before corrective surgery. No complications were reported during the perioperative period, and none of the patients developed postoperative neurological deficits. Conclusions: According to this study, the incidence rate of ISPs in patients with SK was 5.8%, and we recommend that all patients with SK should be evaluated using MRI of the spine before corrective surgery.

CASE REPORT : Aneurysmal Bone Cyst of Sphenoid Bone and Clivus Misdiagnosed as Chordoma: A Case Report

( Fethi Emre Ustabasioglu ),( Cesur Samanci ),( Murat Asik ),( Inanc Yanik ),( Seyma Ozkanli ),( Onur Tutar ),( Zehra Isik Hasiloglu ) 대한뇌종양학회·대한신경종양학회 2015 Brain Tumor Research and Treatment Vol.3 No.2

Aneurysmal bone cysts (ABCs) are benign and rapidly expanding bone destructive lesions of any bone. They are commonly localized in the metaphysis of long bones, whereas skull base ABCs are rare. We report a case of a 21-year-old man who had been misdiagnosed as chordoma and undergone surgery. However, histopathological examination revealed it to be an ABC.