Buckling analysis of sandwich plate using layerwise theory

Arash Ranjbaran,Mohammad Reza Khoshravan,Mahsa Kharazi 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.7

Buckling analysis of sandwich plate was investigated using layerwise method. The formulation was based on the first-order shear deformationtheory, and the Rayleigh-Ritz method was used for approximating and determining the displacement field. The results obtainedfrom layerwise theory was compared with finite element results and showed good agreement. This study demonstrated that layerwisetheory could describe buckling behavior of sandwich plates with high accuracy and represents a more realistic and acceptable descriptionof behavior of the plates with much less computational cost.

Epidemiologic and Socioeconomic Status of Bladder Cancer in Mazandaran province, Northern Iran

Ahmadi, Mohammad,Ranjbaran, Hossein,Amiri, Marzeih Momeninejad,Nozari, Jamshid,Mirzajani, Mohammad Reza,Azadbakht, Mohammad,Hosseinimehr, Seyed Jalal Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.10

Background: Bladder cancer is one the most common malignancies of the genitourinary tract. The present study aimed to assess the epidemiology, of bladder cancer in Mazandaran, a large province in northern Iran as high-incidence cancer area, during a 2-year period. Methods: The data for this study were obtained from the population-based cancer registry of the Vice-Chancellory for Health Affairs of Mazandaran University of Medical Sciences and Mazandaran hospitals between March 1, 2010 and March 1, 2011. Demographic data, including sex, age, residency and symptoms were investigated through careful review of medical records. Using a questionnaire protocol, several variables were assessed for these cases such as smoking, history of opium, vegetable consumption habits, and history of other cancers. Results: A total of 112 cases were analyzed, 98 (87.5%) in men and 14 (12.5%) in women (mean age of $68.0{\pm}14.6$ years). Urban and rural residence were 60.7% and 39.3%. Tobacco and opium use were found in 45.5% and 21.4% of patients, respectively. Approximately 60% consumed vegetables an average of fewer than one time per day. Hematuria was the first symptom in these cases which were mainly diagnosed as having bladder cancer by ultrasonography. Conclusion: The results showed that bladder cancer tends to be found in the elderly and the male to female ratio is high. Macroscopic hematuria is a very important symptom for indicating probably urothelial tumor that should be followed up patients with transabdominal ultrasonography as a routine modality.

A New Method for Developing Seismic Collapse Fragility Curves Grounded on State-Based Philosophy

Aref Baharvand,Abdolrasoul Ranjbaran 한국강구조학회 2020 International Journal of Steel Structures Vol.20 No.2

Since the current process to achieve the collapse fragility curve in practical applications seems too complicated, also time-consuming to dominant by structure designers, the focus of this study is on introducing of a new approach for establishing collapse fragility curves which requires less analytical effort. To achieve this goal, state-based philosophy (SBP) has been taken into consideration. This theory benefits from some similarities in the nature of every failure process in solid mechanics regardless of its source. In this study these similarities are used intelligently in procedure of formulating new fragility function which has couple of unknown parameters. Next, it will be shown that these parameters can be attained from two different sources: the pushover curves of the structure, some selective damage data from incremental dynamic analysis analyses. Finally a complete form of new collapse fragility function which is called "SBP fragility function" proposed as a substitute for conventional collapse fragility function. The most important advantage of this new fragility function is its non-probabilistic structure that will make a huge difference in the amount of effort required to achieve the fragility curves. In this research, in order to ensure the efficiency, accuracy of this fragility function all steps of SBP fragility analyses are done on some special moment frames models, their results are presented.

Seismic Fragility Functions Grounded on State-Based Philosophy: Application to Low to Midrise Steel Frame Buildings

Aref Baharvand,Abdolrasoul Ranjbaran 대한토목학회 2020 KSCE Journal of Civil Engineering Vol.24 No.6

In this study, a new formulation for structural fragility function based on the theory of state-based philosophy (SBP) is introduced. In this innovative approach, gradual changes in stiffness (or flexibility) of the structure is considered as a firm base for describing changes in the state of the structure due to damage from various sources. In this study, the source of damage data is considered ground motions. After formulating state changes by using SBP theory, a new fragility function is proposed. Therefore, this new function is based on observations of various failure stages of the structure and, besides, it is organized specifically for the structural damage data. In order to prove the accuracy of this method, some special moment frames (SMFs) are modeled, and incremental dynamic analysis (IDA) is performed on them. Thus damage data are provided as initial input to the fragility function. After that, the final results of the SBP fragility function are compared with the results of the conventional methods of plotting the fragility curve, and lastly, the fragility curve's accuracy obtained by using this new function is verified. This new fragility function is called ‘SBP fragility function’ and has some advantages over the ordinary fragility functions, which are discussed in this article.

Fully Automated Transcranial Doppler Ultrasound for Middle Cerebral Artery Insonation

Michael J. O’Brien,Amber Y. Dorn,Mina Ranjbaran,Zhaojun Nie,Mateo Scheidt,Nasim Mirnateghi,Shankar Radhakrishnan,Robert B. Hamilton 대한신경초음파학회 2022 대한신경초음파학회지 (JNN) Vol.14 No.1

Background: Transcranial Doppler ultrasound (TCD) is utilized in the assessment of neurological conditions in clinical environments such as the intensive care unit and emergency department. However, obstacles for widespread use of TCD include a lack of trained registered vascular technologists (RVT) and operator variability. We present a study comparing RVT and a fully automated robotic TCD system (NovaGuide rTCD) for insonation of the middle cerebral artery (MCA). Methods: A trained RVT and rTCD sequentially collected bilateral MCA cerebral blood flow velocity (CBFV) from 86 healthy subjects. Mean CBFV (mCBFV) and the signal quality assessment (SQA) acquired manually by RVT and autonomously via rTCD were compared. Comparison metrics evaluated include mean accuracy ratio (MAR), and Bland-Altman mean-difference (MD) between rTCD and RVT with paired t-Test for significance. Bootstrapping was used in the accuracy ratio and mean-time to best signal computations to establish 95% confidence intervals. Results: The mCBFVs and SQAs found by rTCD compared to RVT had MAR of 99.7% (97.7-101.7%) and 102.7% (101.1-104.8%), respectively. The rTCD mean-time to best-quality signal was 0.87 min (0.71-1.05) (RVT was not timed). The mean-difference scores for mCBFV and SQA were MD=-0.43cm/s (p=0.053) and MD=-0.36 (p=0.61), respectively. The rTCD had a 3.5% no-window failure rate compared to RVT no-window rate of 4.1%. Conclusion: Comparison of bilateral TCD signals collected by rTCD and RVT demonstrated equivalence in mCBFV and signal quality, suggesting rTCD’s potential to expand utility of TCD in clinical settings that are resource-limited.

Prevalence of obesity and overweight in Iranian children aged less than 5 years: a systematic review and meta-analysis

Mansori, Kamyar,Khateri, Sorour,Moradi, Yousef,Khazaei, Zaher,Mirzaei, Hossein,Hanis, Shiva Mansouri,Aliabadi, Mehran Asadi,Ranjbaran, Mehdi,Varse, Fatemeh,Parang, Serveh The Korean Pediatric Society 2019 Clinical and Experimental Pediatrics (CEP) Vol.62 No.6

Purpose: The present study aimed to determine the prevalence of childhood obesity and overweight in Iranian children under 5 years of age using a systematic review and meta-analysis. Methods: We searched MEDLINE (PubMed), Web of Science, Google Scholar, Scopus, CINHAL, and the Iranian databases, including Scientific Information Database (www.sid.ir), Iranian Research Institute for Information Science and Technology (Irandoc.ac.ir), Iranmedex (www.iranmedex.com), and Magiran (www.magiran.com), for all articles published between January 1989 and August 2017. Sources of heterogeneity were determined using subgroup analysis and meta-regression. Results: Six articles were ultimately included in the meta-analysis to estimate the pooled prevalence, based on which the prevalence of obesity and overweight were estimated to be 8% (95% confidence interval [CI], 6%-10%) and 9% (95% CI, 7%-11%), respectively. The results of the subgroup analysis showed that the prevalence of obesity in boys and girls was 9% (95% CI, 6%-13%) and 7% (95% CI, 4-10%), respectively, and the prevalence of overweight in boys and girls was 10% (95% CI, 5%-15%) and 9% (95% CI, 5%-13%), respectively. Conclusion: Despite high heterogeneity among the results of the articles included in the meta-analysis, the prevalence of obesity and overweight is higher in Iranian children under 5 years of age. Therefore, parents and the health system must pay more attention to the lifestyle, nutritional habits, and physical activity of these children.

Prevalence of obesity and overweight in Iranian children aged less than 5 years: a systematic review and meta-analysis

Kamyar Mansori,Sorour Khateri,Yousef Moradi,Zaher Khazaei,Hossein Mirzaei,Shiva Mansouri Hanis,Mehran Asadi Aliabadi,Mehdi Ranjbaran,Fatemeh Varse,Serveh Parang 대한소아청소년과학회 2019 Clinical and Experimental Pediatrics (CEP) Vol.62 No.6

Purpose: The present study aimed to determine the prevalence of childhood obesity and overweight in Iranian children under 5 years of age using a systematic review and meta-analysis. Methods: We searched MEDLINE (PubMed), Web of Science, Google Scholar, Scopus, CINHAL, and the Iranian databases, including Scientific Information Database (www.sid.ir), Iranian Research Institute for Information Science and Technology (Irandoc.ac.ir), Iranmedex (www.iranmedex.com), and Magiran (www.magiran.com), for all articles published between January 1989 and August 2017. Sources of heterogeneity were determined using subgroup analysis and meta-regression. Results: Six articles were ultimately included in the meta-analysis to estimate the pooled prevalence, based on which the prevalence of obesity and overweight were estimated to be 8% (95% confidence interval [CI], 6%–10%) and 9% (95% CI, 7%–11%), respectively. The results of the subgroup analysis showed that the prevalence of obesity in boys and girls was 9% (95% CI, 6%–13%) and 7% (95% CI, 4–10%), respectively, and the prevalence of overweight in boys and girls was 10% (95% CI, 5%–15%) and 9% (95% CI, 5%–13%), respectively. Conclusion: Despite high heterogeneity among the results of the articles included in the meta-analysis, the prevalence of obesity and overweight is higher in Iranian children under 5 years of age. Therefore, parents and the health system must pay more attention to the lifestyle, nutritional habits, and physical activity of these children.

Accuracy of Endoscopic Ultrasonography for Determination of Tumor Invasion Depth in Gastric Cancer

Razavi, Seyed Mohsen,Khodadost, Mahmoud,Sohrabi, Masoudreza,Keshavarzi, Azam,Zamani, Farhad,Rakhshani, Naser,Ameli, Mitra,Sadeghi, Reza,Hatami, Khadijeh,Ajdarkosh, Hossein,Golmahi, Zeynab,Ranjbaran, M Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.8

Background: Gastric cancer (GC) is one the common lethal cancers in Iran. Detection of GC in the early stages would assesses to improve the survival of patients. In this study, we attempt to evaluate the accuracy of EUS in detection depth of invasion of GC among Iranian Patients. Materials and Methods: This study is a retrospective study of patients with pathologically confirmed GC. They underwent EUS before initiating the treatment. The accuracy of EUS and agreement between the two methods was evaluated by comparing pre treatment EUS finding with post operative histopathological results. Results: The overall accuracy of EUS for T and N staging was 67.9% and 75.47, respectively. Underestimation and overestimation was seen in 22 (14.2%) and 40 (25.6%) respectively. The EUS was more accurate in large tumors and the tumors located in the middle and lower parts of the stomach. The EUS was more sensitive in T3 staging. The values of weighted Kappa from the T and N staging were 0.53 and 0.66, respectively. Conclusions: EUS is a useful modality for evaluating the depth of invasion of GC. The accuracy of EUS was higher if the tumor was located in the lower parts of the stomach and the size of the tumor was more than 3 cm. Therefore, judgments made upon other criteria evaluated in this study need to be reconsidered.