Analytical and experimental modal analysis of model wind tunnel using microtremor excitation

Sertaç Tuhta 한국풍공학회 2021 Wind and Structures, An International Journal (WAS Vol.32 No.6

In this study was investigated of possibility using the recorded micro tremor data on ground level as ambient vibration input excitation data for investigation and application Experimental Modal Analysis (EMA) on the bench-scale earthquake simulator (The Quanser Shake Table) for model wind tunnel. As known EMA methods (such as EFDD, SSI and so on) are supposed to deal with the ambient responses. For this purpose, analytical and experimental modal analysis of a model wind tunnel for dynamic characteristics was evaluated. 3D Finite element model of the building was evaluated for the model wind tunnel based on the design drawing. Ambient excitation was provided by shake table from the recorded micro tremor ambient vibration data on ground level. Enhanced Frequency Domain Decomposition is used for the output only modal identification. From this study, best correlation is found between mode shapes. Natural frequencies and analytical frequencies in average (only) 2.5% are differences.

GFRP retrofitting effect on the dynamic characteristics of model steel structure

Sertaç Tuhta 국제구조공학회 2018 Steel and Composite Structures, An International J Vol.28 No.2

Nowadays, there are a great number of various structures that have been retrofitted by using different FRP Composites. Due to this, more researches need to be conducted to know more the characteristics of these structures, not only that but also a comparison among them before and after the retrofitting is needed. In this research, a model steel structure is tested using a bench-scale earthquake simulator on the shake table, using recorded micro tremor data, in order to get the dynamic behaviors. Columns of the model steel structure are then retrofitted by using GFRP composite, and then tested on the Quanser shake table by using the recorded micro tremor data. At this stage, it is needed to evaluate the dynamic behaviors of the retrofitted model steel structure. Various types of methods of OMA, such as EFDD, SSI, etc. are used to take action in the ambient responses. Having a purpose to learn more about the effects of GFRP composite, experimental model analysis of both types (retrofitted and no-retrofitted models) is conducted to evaluate their dynamic behaviors. There is a provision of ambient excitation to the shake table by using recorded micro tremor ambient vibration data on ground level. Furthermore, the Enhanced Frequency Domain Decomposition is used through output-only modal identification. At the end of this study, moderate correlation is obtained between mode shapes, periods and damping ratios. The aim of this research is to show and determine the effects of GFRP Composite implementation on structural responses of the model steel structure, in terms of changing its dynamical behaviors. The frequencies for model steel structure and the retrofitted model steel structure are shown to be 33.916% in average difference. Finally, it is shown that, in order to evaluate the period and rigidity of retrofitted structures, OMA might be used.

A CROSS VALIDATION OF CONSUMER-BASED BRAND EQUITY (CBBE) SCALES IN FASHION RETAIL INDUSTRY

Sertaç Çifci,Yüksel Ekinci,Georgina Whyatt 글로벌지식마케팅경영학회 2014 Global Marketing Conference Vol.2014 No.7

The Consumer-Based Brand Equity (CBBE) literature has, in recent years, introduced various CBBE models and measurement scales. This study aims to compare the external validity of the two prominent CBBE models in the fashion retail industry; those introduced by Yoo and Donthu (2011) based on Aaker (1991)’s CBBE concept and Nam et al. (2011). In order to make this comparison, the study collected data from 285 respondents in Turkey. Research findings show that Nam et al.’s (2011) CBBE model is, in the fashion industry context, the more reliable and valid. When the concept of “brand awareness” is included in this model, the psychometric properties of the model are improved.

Evaluation of Serum Zonulin and Occludin Levels in Bipolar Disorder

Zengil Sertaç,Laloğlu Esra 대한신경정신의학회 2023 PSYCHIATRY INVESTIGATION Vol.20 No.4

Objective The etiology of bipolar disorder (BD) is still not fully understood. Little is currently known about the relationship between the interaction the gastrointestinal system and brain function and BD. Zonulin is the only known physiological modulator of tight junctions and is a biomarker for intestinal permeability (IP). Occludin is an integral transmembrane tight junction protein involved in the maintenance and assembly of such junctions. The current study aims to determine whether zonulin and occludin levels are altered in BD and whether they can serve as clinical biomarkers of disease.Methods Forty-four patients with BD and 44 healthy controls were included in this study. The Young Mania Rating Scale (YMRS) was used to determine the severity of manic symptoms, while the Hamilton Depression Rating Scale (HDRS) was used to determine the severity of depressive symptoms, and the Brief Functioning Rating Scale (FAST) to assess functionality. Venous blood samples were taken from all participants and serum zonulin and occludin levels were measured.Results The mean serum zonulin and occludin levels of the patients were significantly higher compared to the healthy control group. There was no difference between manic, depressive, and euthymic patients in terms of zonulin and occludin levels. There was no correlation between the total number of attacks, duration of disease, YMRS, HDRS, FAST scores, and zonulin and occludin levels in the patient group. The groups were divided into three according to body mass index as normal, overweight, and obese. Zonulin and occludin levels increased as body mass index increased and were highest in the obese group.Conclusion The study shows that zonulin and occludin levels in BD increase independently of the disease stage. Consideration of the role of IP in the pathogenesis of BD may be helpful in determining the appropriate treatment modality.

A case report of furosemide extravasation in the hand: a rare cause of compartment syndrome

Güler Sertaç,Kocaşaban Dilber Üçöz 대한응급의학회 2023 Clinical and Experimental Emergency Medicine Vol.10 No.4

In emergency departments, many drugs, fluids, and materials for medical examinations and treatment are typically administered to patients intravenously. One of the most common complications of the intravenous bolus or infusion of drugs is extravasation injuries. These injuries may cause certain morbidities for the patient, increase the cost of treatment, and prolong hospital stays. At the same time, these injuries also carry medicolegal risks for health personnel. Furosemide is a potent diuretic that is commonly used in emergency departments for volume overload conditions. To the best of our knowledge, there have been no cases reported in the literature of furosemide-induced extravasation injury with subsequent compartment syndrome that has required surgical intervention. Presented herein is the case of a 70-year-old female patient who was administered intravenous furosemide from the dorsum of the left hand and whose extravasation injury progressed to compartment syndrome requiring an emergency fasciotomy.

Application of OMA on the bench-scale earthquake simulator using micro tremor data

Azer A. Kasımzade,Sertaç Tuhta 국제구조공학회 2017 Structural Engineering and Mechanics, An Int'l Jou Vol.61 No.2

In this study was investigated of possibility using the recorded micro tremor data on ground level as ambient vibration input excitation data for investigation and application Operational Modal Analysis (OMA) on the bench-scale earthquake simulator (The Quanser Shake Table) for model steel structures. As known OMA methods (such as EFDD, SSI and so on) are supposed to deal with the ambient responses. For this purpose, analytical and experimental modal analysis of a model steel structure for dynamic characteristics was evaluated. 3D Finite element model of the building was evaluated for the model steel structure based on the design drawing. Ambient excitation was provided by shake table from the recorded micro tremor ambient vibration data on ground level. Enhanced Frequency Domain Decomposition is used for the output only modal identification. From this study, best correlation is found between mode shapes. Natural frequencies and analytical frequencies in average (only) 2.8% are differences.

An experimental study on different socket base connections under cyclic loading

Selim Pul,Metin Hüsem,Mehmet Emin Arslan,Sertaç Hamzaçebi 사단법인 한국계산역학회 2014 Computers and Concrete, An International Journal Vol.13 No.3

This paper presents an experimental study on socket base connections of precast reinforced concrete columns. The main purpose of this study is to determine socket base connection which has the closest behavior to monolithic casted column-base joints. For this purpose, six specimens having different column-socket base connection details were tested under cyclic loading. For each test, strength, stiffness, ductility and drift ratios of the specimens were determined. Test results indicated that a suggested connection type is 10% - 30% stronger than the other type of connections under lateral loading. The welded connection (PC-5) had better lateral load carrying capacity and ductility. On the other hand, performance of standard connection (PC-1) which is commonly used in construction was weaker than other connections. Thus, decision of connection type should be referred not only performance but also applicability.

Modified pectoral nerve block versus bi-level erector spinae plane block for postoperative analgesia after radical mastectomy surgery: a prospective, randomized, controlled trial

Cesur Sevim,Aksu Can,Güler Sertaç Ata,Kuş Alparslan 대한마취통증의학회 2023 Korean Journal of Anesthesiology Vol.76 No.4

Background: Regional anesthesia techniques constitute an important part of successful analgesia strategies in the perioperative care of patients undergoing breast surgery. The advent of ultrasound-guided regional anesthesia has led to the development of fascial plane blocks. The large array of blocks available for postoperative analgesia in breast surgery has increased the accessibility of regional anesthesia but has also created a dilemma of choice. This study compared the analgesic efficacy of the ultrasound-guided modified pectoral nerve (PECS) block and erector spinae plane block (ESPB) in patients undergoing radical mastectomy.Methods: Seventy women were enrolled in this prospective, double-blind, randomized control trial. After exclusion, 67 female patients who underwent radical mastectomy were finally analyzed. Ultrasound-guided PECS blocks and ESPBs were performed with 30 ml 0.25% bupivacaine. Postoperative morphine and pain scores were compared between the groups.Results: Postoperative total morphine consumption in the first 24 h was significantly higher in the PECS group (P < 0.001). The ESPB group exhibited significantly reduced morphine consumption at all postoperative time points. Numeric rating scale scores were lower in the ESPB group at 6, 12, and 24 h postoperatively at rest and when coughing.Conclusions: Ultrasound-guided bi-level ESPBs provided better postoperative analgesia than PECS blocks after radical mastectomy surgery.

A CROSS VALIDATION OF CONSUMER-BASED BRAND EQUITY (CBBE) SCALES IN FASHION RETAIL INDUSTRY

Serta? ?ifci,Y?ksel Ekinci,Georgina Whyatt 글로벌지식마케팅경영학회 2014 Global Marketing Conference Vol.2014 No.7

The Consumer-Based Brand Equity (CBBE) literature has, in recent years, introduced various CBBE models and measurement scales. This study aims to compare the external validity of the two prominent CBBE models in the fashion retail industry; those introduced by Yoo and Donthu (2011) based on Aaker (1991)’s CBBE concept and Nam et al. (2011). In order to make this comparison, the study collected data from 285 respondents in Turkey. Research findings show that Nam et al.’s (2011) CBBE model is, in the fashion industry context, the more reliable and valid. When the concept of “brand awareness” is included in this model, the psychometric properties of the model are improved.