Prediction of force reduction factor (R) of prefabricated industrial buildings using neural networks

Arslan, M. Hakan,Ceylan, Murat,Kaltakci, Yaspr M.,Ozbay, Yuksel,Gulay, Fatma Gulten Techno-Press 2007 Structural Engineering and Mechanics, An Int'l Jou Vol.27 No.2

The force (load) reduction factor, R, which is one of the most important parameters in earthquake load calculation, is independent of the dimensions of the structure but is defined on the basis of the load bearing system of the structure as defined in earthquake codes. Significant damages and failures were experienced on prefabricated reinforced concrete structures during the last three major earthquakes in Turkey (Adana 1998, Kocaeli 1999, Duzce 1999) and the experts are still discussing the main reasons of those failures. Most of them agreed that they resulted mainly from the earthquake force reduction factor, R that is incorrectly selected during design processes, in addition to all other detailing errors. Thus this wide spread damages caused by the earthquake to prefabricated structures aroused suspicion about the correctness of the R coefficient recommended in the current Turkish Earthquake Codes (TEC - 98). In this study, an attempt was made for an approximate determination of R coefficient for widely utilized prefabricated structure types (single-floor single-span) with variable dimensions. According to the selecting variable dimensions, 140 sample frames were computed using pushover analysis. The force reduction factor R was calculated by load-displacement curves obtained pushover analysis for each frame. Then, formulated artificial neural network method was trained by using 107 of the 140 sample frames. For the training various algorithms were used. The method was applied and used for the prediction of the R rest 33 frames with about 92% accuracy. The paper also aims at proposing the authorities to change the R coefficient values predicted in TEC - 98 for prefabricated concrete structures.

Effects of endodontic treatment on salivary levels of CGRP and substance P: a pilot study

Arslan, Hakan,Yildiz, Ezgi Doganay,Koseoglu, Serhat The Korean Academy of Conservative Dentistry 2020 Restorative Dentistry & Endodontics Vol.45 No.3

Objectives: The aim of this study was to evaluate the effects of endodontic treatment on levels of substance P (SP) and calcitonin gene-related peptide (CGRP) in the saliva of patients with symptomatic apical periodontitis. Materials and Methods: Twelve patients with mandibular molars with symptomatic apical periodontitis were enrolled in this study. An initial saliva sample was collected just before administration of anesthesia for root canal treatment, which was performed at the first visit. A second saliva sample was collected at a control visit 1 week after treatment. Salivary SP and CGRP levels were evaluated quantitatively using biochemical assays. The data were analyzed using Pearson correlation analysis, the paired samples t-test, and the Mann-Whitney U test (p = 0.05). Results: The postoperative salivary level of SP was significantly lower than the preoperative level (p = 0.005). However, the postoperative salivary level of CGRP was similar to the preoperative level (p = 0.932). Visual analog scale (VAS) scores of patients' subjective pain were found to be positively correlated with salivary levels of SP (r = 0.421; p = 0.040). No statistically significant correlations were observed between salivary levels of CGRP and VAS scores for patients' subjective percussion tenderness (p = 0.533) or VAS scores for patients' subjective pain (p = 0.459). Conclusions: According to the results of the present study, salivary SP levels may be used as an objective indicator in the diagnosis and assessment of the degree of pain in endodontic diseases.

Prediction of force reduction factor (R) of prefabricated industrial buildings using neural networks

M. Hakan Arslan,Murat Ceylan,M. Yasar Kaltakci,Yüksel Ozbay,Fatma Gulten Gulay 국제구조공학회 2007 Structural Engineering and Mechanics, An Int'l Jou Vol.27 No.2

The force (load) reduction factor, R, which is one of the most important parameters in earthquake load calculation, is independent of the dimensions of the structure but is defined on the basis of the load bearing system of the structure as defined in earthquake codes. Significant damages and failures were experienced on prefabricated reinforced concrete structures during the last three major earthquakes in Turkey (Adana 1998, Kocaeli 1999, Duzce 1999) and the experts are still discussing the main reasons of those failures. Most of them agreed that they resulted mainly from the earthquake force reduction factor, R that is incorrectly selected during design processes, in addition to all other detailing errors. Thus this wide spread damages caused by the earthquake to prefabricated structures aroused suspicion about the correctness of the R coefficient recommended in the current Turkish Earthquake Codes (TEC - 98). In this study, an attempt was made for an approximate determination of R coefficient for widely utilized prefabricated structure types (single-floor single-span) with variable dimensions. According to the selecting variable dimensions, 140 sample frames were computed using pushover analysis. The force reduction factor R was calculated by load-displacement curves obtained pushover analysis for each frame. Then, formulated artificial neural network method was trained by using 107 of the 140 sample frames. For the training various algorithms were used. The method was applied and used for the prediction of the R rest 33 frames with about 92% accuracy. The paper also aims at proposing the authorities to change the R coefficient values predicted in TEC - 98 for prefabricated concrete structures.

Estimation of Curvature and Displacement Ductility in Reinforced Concrete Buildings

M. Hakan Arslan 대한토목학회 2012 KSCE JOURNAL OF CIVIL ENGINEERING Vol.16 No.5

Ensuring sufficient ductility in building load bearing systems and elements of the load bearing system is quite important for their seismic performance. The Seismic Codes stipulate that certain requirements must be met to maintain ductility values above a certain level. The purpose of this study is to determine how ductility values of both elements and load bearing systems vary as parameters related to the conditions specified in the codes change and as estimates of these values are used. With this aim in mind, the curvature ductility in columns and beams of a four-storey Reinforced Concrete (RC) building differs depending on parameters that include the axial load level, longitudinal reinforcement, transverse reinforcement, compression bar ratio and concrete strength. The value of the curvature ductility was found to vary according to the number of parameters and variance range, which was found to be 60 and 135in the beam section and column section, respectively. Later, a pushover analysis was applied to 540 different statuses of the sample RC system for the same parameters, and the ratio variations and respective displacement (global) ductility of the frames were calculated. The relationship between obtained ductility values with the parameters, as well as the accuracy of the established model,were estimated using regression analyses (Multi-linear and Nonlinear Regression (MLR, NLR)) and 11 various Artificial Neural Networks (ANN) methods. According to the estimation methods, it was found that the test parameters that significantly affect curvature ductility values are not sufficient to explain the displacement ductility values. On the other hand, it was seen that the estimation strength of ANNs proved to be greater than MLR in both curvature ductility and displacement ductility. Outcomes also indicated that the NLR model exhibits superior performance for estimating displacement ductility.

Can Cochlear Nerve Size Assessment With Magnetic Resonance Enhance the Understanding of Idiopathic Sudden Sensorineural Hearing Loss?

Arslan Hande,Özdemir Meltem,Kavak Rasime Pelin,Keseroğlu Kemal,Mutlu Murad,Korkmaz Mehmet Hakan 대한청각학회 2024 Journal of Audiology & Otology Vol.28 No.1

Background and Objectives: Idiopathic sudden sensorineural hearing loss (ISSHL) is a rapid loss of hearing, exceeding 30 dB in at least 3 consecutive frequencies within 3 days, without any identifiable cause despite thorough investigations. Currently, the etiology and pathogenesis of ISSHL have not been fully elucidated. This study aimed to assess the size of the cochlear nerve in patients with ISSHL and explore its relationship with pretreatment audiograms and treatment response.Subjects and Methods: A total of 125 patients (59 [47.2%] women; mean age 47.7±13.8 years [minimum-maximum: 21-76]) and 60 healthy participants (27 [45%] women; mean age 45.7±16.8 years [minimum-maximum: 20-76]) as a control group were included in this study. The size of the cochlear nerve was assessed on the affected side, compared to the control group, as well as on the unaffected side. Pretreatment and posttreatment audiological values were also analyzed.Results: The cross-sectional area (CSA), vertical diameter (VD), and horizontal diameter (HD) of the CN were found to be smaller on the affected side of ISSHL patients compared to the control group (p<0.01; p=0.04; p=0.02, respectively). In the study group (affected side of ISSHL patients), there were no significant differences in VD, HD, and CSA values between pretreatment audiogram types (p=0.23; p=0.53; p=0.39, respectively), and initial hearing levels (p=0.16; p=0.22; p=0.23, respectively). Furthermore, there were no significant differences in VD, HD, and CSA values between the recovery groups according to Furuhashi criteria (p=0.18; p=0.37; p=0.27, respectively).Conclusions: The size of the CN may be a risk factor for ISSHL, but it does not affect the type of audiogram curves and was not prognostic in terms of treatment response.

Predictive factors affecting morcellation efficiency in holmium laser enucleation of the prostate

Hakan Anıl,Ahmet Güzel,Ali Yıldız,Serkan Akdemir,Kaan Karamık,Murat Arslan 대한비뇨의학회 2023 Investigative and Clinical Urology Vol.64 No.4

Purpose: To determine the factors affecting morcellation efficiency in holmium laser enucleation of the prostate (HoLEP) surgery. Materials and Methods: Patients who underwent HoLEP surgery by a single surgeon between 2018 and 2022 were included in the study. Our primary outcome of interest in this study was morcellation efficiency. The effect of preoperative and perioperative variables on morcellation efficiency was evaluated with linear regression analysis. Results: A total of 410 patients were included in the study. The mean morcellation efficiency was 6.95±1.70 g/min. Univariable and multivariable linear regression analysis was performed to identify factors affecting morcellation efficiency. Presence of the “beach ball” effect (small, round prostatic tissue fragments that are fibrotic and difficult to morcellate), the learning curve, resectoscope sheath type, prostate-specific antigen (PSA) density, morcellated tissue weight, and the presence of prostate calcification were found to be independent predictive factors (β=-1.107, 95% CI: -1.59 to -0.55, p<0.001; β=-0.514, 95% CI: -0.85 to -0.17, p=0.003; β=-0.394, 95% CI: -0.65 to -0.13, p=0.003; β=-0.302, 95% CI: -0.59 to -0.09, p=0.043; β=0.062, 95% CI: 0.05 to 0.06, p<0.001; β=-0.329, 95% CI: -0.55 to -0.10, p=0.004; respectively). Conclusions: This study reports that presence of the beach ball effect, the learning curve, small resectoscope sheath, PSA density, and presence of prostate calcification negatively affect morcellation efficiency. On the contrary, morcellated tissue weight has a linear relationship with morcellation efficiency.

Slide Session : OS-NEP-01 ; Nephrology : Dipping Status in Individuals Monitored by Ambulatory Blood Pressure Measurements

( Hakan Sarlak ),( Fatih Bulucu ),( Erol Arslan ),( Seref Demirbas ),( Kenan Saglam ) 대한내과학회 2014 대한내과학회 추계학술대회 Vol.2014 No.1

Considering the low rate of dipping, the presence of an evening dose seems to be important in elderly hypertensive women when arranging the treatment for their hypertension. In monotherapy, divided doses will be rational.

Impact of Poster Presentations on Academic Knowledge Transfer from the Oncologist Perspective in Turkey

Arslan, Deniz,Koca, Timur,Tastekin, Didem,Basaran, Hamit,Bozcuk, Hakan Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.18

Background: Currently poster presentations offer a common visual medium for knowledge transfer by a wide range of health professionals. Our study aimed to determine the scientific importance of poster presentations for Medical and Radiation Oncologists. Methods: A survey form including 40 questions was distributed to a total of 131 oncologists experienced in poster presentations. One hundred completed survey forms were included in the study. Descriptive statistics and modified thematic analyses were performed on the responses. Results: Overall 64% of the participants agreed that posters were a good medium for knowledge transfer. Some 88% agreed that concise and clear styled presentations would increase appealing interests for poster contents. Visual appearance was cited more influential than content of the subject; 70% of participants agreed that appearances of posters could help to draw more viewer attention. Of respondents, 63% believed that posters accompanied by their author were more attractive for congress attendees, and 33% of them declared that the halo effect of the poster presenter was also important. Conclusion: The present study indicated that intelligibility, appearance and visuality of posters are most important factors from the aspect of oncologist participants. Presenters must take into account these important points when preparing their academic posters.

Poster Session : PS 0098 ; Cardiology : R Wave Amplitude of Avl Derivation Seems to be Important in Predicting Arterial Stiffness Parameters

( Hakan Sarlak ),( Fatih Bulucu ),( Erol Arslan ),( Seref Demirbas ),( Muharrem Akhan ),( Sait Demirkol ) 대한내과학회 2014 대한내과학회 추계학술대회 Vol.2014 No.1

Background: Studies have shown that arterial stiffness is an independent predictor of cardiovascular diseases. Left ventricular hypertrophy (LVH) is an independent risk factor for early death. It is caused by malignant ventricular arrhythmias due to ventricular hypertrophy. In this study we aimed to investigate the relationships between arterial stiffness parameters and electrocardiographic criteria for LVH. Methods: A total of 59 subjects (30 females, 29 males) were included into the study. The subjects were the patients having arterial stiffness and electrocardiographic measurements applied in the internal medicine out-patient clinics for their chronic diseases or based upon their complaints. Results: The pulse wave velocity (PWV) was signifi cantly associated with Sokolow-Lyon ‘II’ (r=0.269; p=0.041) and the central aortic pressure (CAP) was signifi cantly associated with Sokolow-Lyon ‘II’ and Romhilt-Estes Score (r=0.303; p=0.021 and r=0.275; p=0.037, respectively) in whole group. The augmentation index of aortic (AIXao) was signifi cantly associated with Sokolow-Lyon ‘II’ (r=0.381; p=0.042) in men. The CAP was signifi cantly associated with Sokolow-Lyon ‘II’, Cornell Product and Romhilt-Estes Score (r=0.524; p=0.004, r=0.402; p=0.031 and r=0.444; p=0.016, respectively) in women. Conclusions: These data suggest that some arterial stiffness parameters may be predicted by using R wave amplitude of aVL derivation. Although our small scale preliminary investigation confers some clues for this approach, it is obvious that large scale and more detailed investigations are needed.

Survival Results and Prognostic Factors in T4 N0-3 Non-small Cell Lung Cancer Patients According to the AJCC 7^th Edition Staging System

Arslan, Deniz,Bozcuk, Hakan,Gunduz, Seyda,Tural, Deniz,Tattli, Ali Murat,Uysal, Mukremin,Goksu, Sema Sezgin,Bassorgun, Cumhur Ibrahim,Koral, Lokman,Coskun, Hasan Senol,Ozdogan, Mustafa,Savas, Burhan Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.6

Background: The American Joint Committee on Cancer (AJCC) published a new staging system ($7^{th}$ edition) in 2009. In our study, we evaluated the survival results and prognostic factors among T4 local advanced non-small cell lung cancer (LA-NSCLC) patients in a large heterogeneous group, in accordance with this new system. Materials and Methods: We retrospectively evaluated the files of 122 T4 N0-3 M0 LA-NSCLC patients, identified according to the new staging system, treated at two centers between November 2003 and June 2012. Variables correlating with univariate survival at p<0.20 were later included in multivariate Cox regression analysis. Here, selection of relevant predictors of survival was carried out in accordance with the likelihood ratio formula with p<0.05 regarded as significant. Results: The median age was 60 and the median follow-up period was 17.4 months. Median overall survival (OS) was 18.3 months, the 1 year overall survival (OS) rate was 72%, and the 5 year OS rate was 28%. Statistically significant predictors of survival were (p<0.20) ECOG-PS (Eastern Cooperative Oncology Group Performance Status), age, T4 factor subgroup, stage and primary treatment in OS univariate analysis. On multivariate analysis for OS ECOG-PS (p=0.001), diagnostic stage (p=0.021), and primary treatment (p=0.004) were significant. In the group receiving non-curative treatment, the median OS was 11.0 months, while it was 19.0 months in the definitive RT group and 26.6 months in the curative treatment group. There was a significant difference between the non-curative group and the groups which had definitive RT and curative operations (respectively p<0.001 and p=0.001) in terms of OS, but not between the groups which had definitive RT and curative operations. The median event free survival (EFS) rate was 9.9 months, with rates of 46% and 19% at 3 and 5 years, respectively. On univariate analysis of EFS rate with ECOG-PS, weight loss and staging, statistical significance was found only for thorax computerized tomography (CT)+18F-fluorodeoxy-glucose positron emission tomography-CT (PET-CT) use, stage and primary treatment (p<0.20). In multivariate analysis with EFS, only the primary treatment was statistically significant (p=0.001). In the group receiving non-curative treatment, the median EFS was 10.5 months while in the curative operation group it was 14.7 months. When all the primary treatment groups were taken into consideration, grade III/IV side effect swas observed in 57 patients (46.6%). Esophagitis was most prominent among those that received definitive radiotherapy. Conclusions: Independent prognostic factors among these 122 heterogeneous LA-NSCLC T4 N0-3 M0 patients were age at diagnosis, ECOG-PS, stage and primary treatment, the last also being a significant prognostic indicator of EFS. Our findings point to the importance of appropriate staging and a multidisciplinary approach with modern imaging methods in this patient group. In those with T4 lesions, treatment selection and the effective use of curative potential should be the most important goal of clinical care.