5 research outputs found
Strengthening of MRF RC frames located in seismic areas with BRB and FRP
This paper presents the structural analysis of a RC frame GLD according to 50 years old Romanian standards. The design of the RC frame is followed by the structural analysis of the same frame strengthened by means of two methods. The first strengthening method is using a dissipative system represented by a BRB system applied in the middle spans of the frame as an inverted V system, pinned at the ends. The second method of strengthening is the confining of the columns, from the first two stories, by means of FRP techniques. In the first step the two methods are applied and analyzed separately on the frame, then a combination of them is applied and analysed
Multivariate Analysis of the Predicted Probability of Smoking Behavior of Foster Care Minors: Results of a Study from Romania
Background: There are a multitude of factors that influence smoking status, and minors from the social protection system are a vulnerable category in terms of smoking. Methods: The objective of this research was to assess the degree of smoking dependence and to identify potential predictors of smoking status in foster care teenagers. Smoker status was confirmed by dosing CO in the exhaled air, and the degree of dependence was assessed using the Fagerström score. We performed a multivariate logistic regression analysis. Results: From the 275 foster care minors, 22.5% were current smokers. Exhaled CO was not influenced by general demographic factors, was associated with the frequency of smoking, and was positively correlated with the estimated number of cigarettes consumed daily and with the Fagerström score. The calculated probability of being a smoker was less than 20.4% in 75% of nonsmokers, whereas 75% of actual smokers had a predicted probability higher than 30.3%. Conclusions: In addition to age, gender, social environment, previous exposure to secondhand smoking, and residential type of foster care system, the expressed opinions regarding the health effects of tobacco use were associated with smoking in foster care teenagers
New Dental Implant with 3D Shock Absorbers and Tooth-Like Mobility—Prototype Development, Finite Element Analysis (FEA), and Mechanical Testing
Background: Once inserted and osseointegrated, dental implants become ankylosed, which makes them immobile with respect to the alveolar bone. The present paper describes the development of a new and original implant design which replicates the 3D physiological mobility of natural teeth. The first phase of the test followed the resistance of the implant to mechanical stress as well as the behavior of the surrounding bone. Modifications to the design were made after the first set of results. In the second stage, mechanical tests in conjunction with finite element analysis were performed to test the improved implant design. Methods: In order to test the new concept, 6 titanium alloy (Ti6Al4V) implants were produced (milling). The implants were fitted into the dynamic testing device. The initial mobility was measured for each implant as well as their mobility after several test cycles. In the second stage, 10 implants with the modified design were produced. The testing protocol included mechanical testing and finite element analysis. Results: The initial testing protocol was applied almost entirely successfully. Premature fracturing of some implants and fitting blocks occurred and the testing protocol was readjusted. The issues in the initial test helped design the final testing protocol and the new implants with improved mechanical performance. Conclusion: The new prototype proved the efficiency of the concept. The initial tests pointed out the need for design improvement and the following tests validated the concept