Photoionization of Fullerens and Atoms Confined in Fullerenes

The photoionization cross sections of small fullerenes (C28, C32, C40, C44, and C50), and the outer and near-outer shells of atoms (noble gases, alkaline earth) confined endohedrally inside a C60 molecule are calculated employing a time-dependent local density approximation formulation. Plasmon and confinement resonances are found to be a general feature of these cross sections, and dramatic interchannel coupling effects, significantly increasing the atomic cross sections, are exhibited in all cases in the vicinity of the C60 plasmons. Hybridization effects, the mixing of the atomic and cage bound state wave functions, are also found, but no systematics of the hybridization present themselves. Also, in the case of Ar@C60, Inter-atomic Columbic decay (ICD) has been found and studied

The frequency of expressions and proverbs in different Iranian generations' speech styles

Change is one of the fundamentals of every language. Every community consists of different generations with various perspectives toward life. The difference among different generations' vernaculars are so drastic that it would not be an exaggeration to claim that every generation of a society or a speech community has its own language or vernacular which distinguishes it from other generations or age-groups of the society in lexico-grammatical terms. This study put the frequency of expressions and proverbs in different generations' speech styles under investigation. Hence, inspired by stratified randomization technique, the researcher randomly selected a group of 24 middle-aged and similarly a group of 24 teenager participants of the two genders. Each of the age-groups consisted of 12 male and 12 female subjects in order to provide the possibility to determine the role of gender on expression or proverb usage. All the subjects were individually interviewed for elicitation of the needed data then their sentences were recorded and accurately transcribed for further investigation. By counting the expressions or proverbs in sentences of male/female teenagers' and middle-aged subjects of the research, their expression and proverb usage frequencies were illuminated. The study's results suggested that middle-aged speakers of Iranian community employed expressions and proverbs more than teenagers. This implies that the older would have a stronger relationship with the literature and are more satisfied with their culture and identity. Middle-aged subjects used those expressions which were deeply rooted in the literature and culture while teenagers were highly in use of those expressions and proverbs which were suddenly entered into the lexicon of the society by the advent of new television series or expanded advertisements of mass media, for example. Furthermore, it was found that males generally were more interested in using expression and proverb in their daily conversations than females

Shear strength of cross laminated timber-concrete connections reinforced with carbon fibre polymer composites

This paper presents an experimental study on the mechanical behaviour of four different timber concrete composite (TCC) connections. Experimental shear tests were conducted to assess the strength and stiffness of the composite connection system. A new type of connection based on carbon fibre reinforced polymer (CFRP) was also proposed to achieve enhanced performance at the cross laminated timber. The stiffness and strength for each type of connection were identified by assessing the load-slip behaviour and load capacity. In addition, the relationship between applied force and slip characteristic of each type of connecting system was also established. Results showed that the addition of CFRP to the connection can effectively improve the maximum shear capacity and stiffness of the connection.ARC DE150101703, ARC DP140100529, ARC LP14010059

Stereoscopic modelling and monitoring of the roughness in concrete pavements

The detection and measurement of surface properties, such as cracks and roughness, on concrete structures have been of significant interest in recent years. Crack formation, width and propagation as well as surface roughness are important indicators of the structural integrity and condition of a concrete pavement that can determine the need for an upgrade or maintenance operation in roads and bridges. The use of non-destructive testing techniques for development of analytical and numerical processing tools that enables the efficient measurement of surface properties is the aim of this work. In the proposed framework, a stereo camera set-up is utilised to map and register surface roughness of a concrete pavement. The benefit of using a depth image to create a surface map lies in its low-cost and ability to provide depth changes at a highly-refined level with approximately 0.05 mm accuracy. Concrete samples of different roughness are used to assess the viability of such technique in enhancing inspection ability and the effectiveness of robust structural health monitoring and assessment. The focus is placed on: the acquisition of spatial and visual data and creating a 3D point cloud mesh using XYZ and RGB data; an efficient algorithm for the registration and analysis of XYZ- RGB data; and accuracy assessment of stereo cameras in detection and measurement. The investigation herein outlined capitalises on the potential for stereo cameras in developing a pipeline for data acquisition, detection and measurement of cracks and surface roughness in concrete structures.ARC DE150101703, ARC DP140100529, ARC LP14010059

Bond behaviour of fibre reinforced polymer strengthened concrete structures using advanced composite processing techniques

The research presented in this thesis consists of experimental, analytical and numerical studies of the interface behaviour in adhesively bonded joints manufactured with common and new developed FRP processing methods. The wet lay-up and pultruded laminates are categorized as common, and vacuum assisted resin infusion (VARI) and heated vacuum bag only (HVBO) are considered as recently developed processing methods. The effect of the principal parameters on the interface behaviour is studied through several series of experiments. Local and global investigations of the interface indicate that through application of VARI and HVBO, a bond with high quality is achievable. To monitor the bond characteristics during the experiments, a new single lap shear test set-up is developed and employed in this research. Results indicate that accurate and reliable results can be achieved in terms of interfacial responses using modified single lap shear test set-up. Through the experimental program, the effect of the bondline thickness is specifically studied for different types of processing techniques. Investigation on the local and global bond parameters show that after a specific bondline thickness, load carrying capacity of the joint does not change. Therefore, a new concept, the optimum bondline thickness, is proposed and the load-bondline thickness relationships are adopted based on the nonlinear regression analysis of the experimental results. Since in this research various techniques are compared and considering this fact that the fabrication method in these techniques is different therefore, the bond characteristics are scaled in a way that the comparison can be possible. This scaling factor here is called “equalisation of the processing techniques.” A new analytical approach is presented for determination of the interface behaviour in FRP-to-concrete bonded joints. Based on the boundary conditions, two distinctive methods are proposed to predict the bond-slip relationships and interfacial fracture energy. Since the models are derived solely based on boundary conditions of the joints, they can be applied to any type of the FRP processing technique. In addition, the interface characteristics are obtained from the value of the applied load at each stage and the properties of the materials which are available in most of the tests. Comparison between the experimental and the analytical results of the maximum load carrying capacity, the strain, shear stress and slip profiles and also the fracture energy of the interface indicate that the proposed analytical methods are capable to predict the interfacial behaviour between the FRP and concrete substrates with satisfactory precision. Finally, considering the proper material constitutive laws, a finite element analysis is carried out and the outcomes are presented

Chattering-free sliding mode control with a fuzzy model for structural applications

This paper proposes a chattering-free sliding mode control (CFSMC) method for seismically excited structures. The method is based on a fuzzy logic (FL) model applied to smooth the control force and eliminate chattering, where the switching part of the control law is replaced by an FL output. The CFSMC is robust and keeps the advantages of the conventional sliding mode control (SMC), whilst removing the chattering and avoiding the time-consuming process of generating fuzzy rule basis. The proposed method is tested on an 8-story shear frame equipped with an active tendon system. Results indicate that the new method not only can effectively enhance the seismic performance of the structural system compared to the SMC, but also ensure system stability and high accuracy with less computational cost. The CFSMC also requires less amount of energy from the active tendon system to produce the desired structural dynamic response.ARC DE150101703 and ARC LP14010059

Seismic resilience of retrofitted reinforced concrete buildings

The fundamentals of the seismic resilience and evaluation method are presented. The evaluation is based on a non-dimensional analytical function for loss variation and a linear recovery function for a community in an average state of preparedness within a specified 'recovery period'. The loss function is a normalized function where the drop of functionality right after the extreme event. The formulated framework, applied for a complex system of six hospitals (considering direct and indirect losses), is employed for low and medium-rise retrofitted reinforced concrete buildings in which the seismic performance has been evaluated by the displacement-based design method. Although this type of design prevents loss of people life it cannot maintain functionality or limit damages. A newly developed Resilience-Based Earthquake Design is promising to address these demands. This research shows that the FRP retrofit is more effective than steel bracing in terms of improving performance and ductility in low-rise RC buildings and the measuring seismic resilience shows an enhanced value as opposed to the un-retrofitted structure

Assessment of the ratio of cross-matched to transfused blood amounts in pregnant patients in Alzahra Hospital in Tabriz before and after the implementation of the health reform program in 2013-2015

Background: Postpartum hemorrhage is the most common cause of mortality in women with vaginal or cesarean delivery. WHO statistics shows that about 500 thousands women have died of complications related to pregnancy or during childbirth in 2013. haemorrhage probability is the main reason to order blood requests in delivery and cesarean units. The purpose of this study is to evaluate the ratio of cross-matched to transfused blood in pregnant women during one year before and after the implementation of health reform program.Materials and Methods: In this retrospective descriptive study, the requests of blood reserves for pregnant patients with the gravid of 34±7 weeks and the age of 30±16 years old in two periods, before and after the implementation of health reform program were being collected and compared. Blood group antiserums and anti-human globulins with bovine albumins were purchased from LORN company and Baharafshan Company respectively.Results: The total number of requests for reserved cross-matched blood during the year before the health reform program were 2837 units which 277 of them had been transfused and a year later the total number of requests was for 3029 units, which 270 of them had been transfused. This study showed 6.76 percent increase in requests and 2.53 percent decrease in transfusion in comparison with its past year.Conclusion: The implementation of health reform program have accompanied by relative reduction of cesarean but considerable increase in vaginal delivery, and to prevent blood loss complications, the requests for reserved cross-matched blood have been increased without noticeable change in the proportion of necessarily transfused amount of them

Partial safety factors for prestressed concrete girders strengthened with CFRP laminates

This paper provides a framework for the calibration of partial safety factors in prestressed concrete (PC) girders strengthened in flexure with carbon fibre-reinforced polymer (CFRP) laminates. A hybrid approach was proposed to take advantage of comprehensive non-linear numerical models in reliability analysis using a first order reliability method (FORM) in conjunction to the response surface method (RSM). The PC girders selected for analyses were taken from real structures designed and built since the 1980s, based on old standards, now requiring strengthening and upgrade due to partial corrosion of prestressing strands. Using the proposed approach, a sensitivity analysis was performed to identify the most relevant variables and assess the area of CFRP laminates needed to restore the capacity to new design standards. Following this study, a partial safety factor was proposed for strengthening PC girders using CFRP laminates. A sensitivity analysis also showed the traffic loads and model uncertainties to be the most important variables for calibration