Seismic Behaviour and Retrofit of Historic Masonry Minaret

U radu se razmatra dinamičko ponašanje blokovima zidanog minareta povijesne džamije u Istanbulu i metoda protupotresne sanacije. S obzirom na visoku seizmičku aktivnost regije, za određivanje bočnih pomaka i načina otkazivanja uslijed seizmičkih djelovanja odabran je prostorni model konačnih elemenata. Provedene analize pokazuju da se najveća oštećenja obično pojavljuju u podnožju i donjem dijelu minareta, te da se ojačavanjem tih dijelova trakama od polimera armiranog vlaknima (engl. FRP - Fiber Reinforced Polymer) poboljšava otpornost na bočne sile. Postignuti rezultati su u smislu seizmičke zaštite obećavajući.The dynamic behaviour of block masonry minaret of a historical mosque in Istanbul is analyzed, and a seismic retrofit method is proposed. Due to high seismicity of the region, a 3D finite element model is used to determine lateral displacements and failure modes under seismic load. The analyses show that the highest damage usually occurs at the base and the lower part of the minaret, and that lateral behaviour can be improved by strengthening these sections with fiber reinforced polymer (FRP) sheets. The results obtained are promising in terms of seismic protection

Seismic Response Analysis of Masonry Minaret and Possible Strengthening by Fiber Reinforced Cementitious Matrix (FRCM) Materials

This paper presents the analytical study on the dynamic response of a natural stone block masonry minaret of a historical mosque located in Istanbul, Turkey. A three-dimensional finite element model of the whole minaret, adjusted with former in situ ambient vibration test results, was used in order to get probable lateral displacements, stresses, and understanding of failure modes under seismic loading. Particularly, FEM has been used to evaluate the seismic safety of the minaret in present-day condition and after the application of a proposed strengthening method. In this method, by utilizing the fiber reinforced cementitious matrix (FRCM) material, the critical cross-sections were jacketed. The appearing damage for the bare minaret obtained from FEM analyses was located at the boot and transition part of the minaret. After FRCM material was wrapped around these critical cross-sections, the analytical results indicated that such method appears effective in terms of the seismic response. It also appears less invasive in terms of the conservation of historical heritage like minarets without causing aesthetic conflict on the existing structure when compared to other available techniques

Chemical composition of subcritical water extraction extract of Tribulus Terrestris

Subcritical water extraction of Tribulus terrestris leaves and fruits was performed at 100 ºC and 60 atm for 30 min. Chemical composition of volatile extracts was investigated.  A simple lactone compound Loliolide (23,82%) was  main components associated with 26 identified molecules which are mostly oxygenated compounds

Evaluation of the Repeatability and the Reproducibility of AL-Scan Measurements Obtained by Residents

. Purpose. To assess the repeatability and reproducibility of ocular biometry and intraocular lens (IOL) power measurements obtained by ophthalmology residents using an AL-Scan device, a novel optical biometer. Methods. Two ophthalmology residents were instructed regarding the AL-Scan device. Both performed ocular biometry and IOL power measurements using AL-Scan, three times on each of 128 eyes, independently of one another. Corneal keratometry readings, horizontal iris width, central corneal thickness, anterior chamber depth, pupil size, and axial length values measured by both residents were recorded together with IOL power values calculated on the basis of four different IOL calculation formulas (SRK/T, Holladay, and HofferQ). Repeatability and reproducibility of the measurements obtained were analyzed using the intraclass correlation coefficient (ICC). Results. Repeatability (ICC, 0.872-0.999 for resident 1 versus 0.905-0.999 for resident 2) and reproducibility (ICC, 0.916-0.999) were high for all biometric measurements. Repeatability (ICC, 0.981-0.983 for resident 1 versus 0.995-0.996 for resident 2) and reproducibility were also high for all IOL power measurements (ICC, 0.996 for all). Conclusions. The AL-Scan device exhibits good repeatability and reproducibility in all biometric measurements and IOL power calculations, independent of the operator concerned

Role of Chest Radiography in the Management of Patients with Chest Pain and Dyspnea in the Emergency Department

SUMMARY Objectives: Study objective was to investigate the contribution of chest radiography on the management of patients with chest pain or dyspnea and to analyze the consistency of the treatment strategies before and after chest radiography. Materials and Methods: All consecutive adult patients who were admitted to the emergency department with the chief complaint of non-traumatic chest pain or dyspnea who had a chest radiography were enrolled in the study. Results: The impact of chest radiography on the management plan was investigated. The management plans were changed in 12.9% of 387 subjects after chest radiography. The change of management plans was not significantly related to age, sex, past medical history and radiographic technique. Presenting symptom, initial diagnosis, chest radiography indications,the initial management plan were all associated with management plan change after radiographic evaluation. Conclusion: Chest radiographs may contribute to the diagnosis and treatment of selected emergency department patients with dyspnea and chest pain. Radiographies ordered routinely for hospital admission or for preoperation testing had no impact on the patient management plan in the emergency department

Unraveling Molecular Fingerprints of Catalytic Sulfur Poisoning at the Nanometer Scale with Near-Field Infrared Spectroscopy

Fundamental understanding of catalytic deactivation phenomena such as sulfur poisoning occurring on metal/metal-oxide interfaces is essential for the development of high-performance heterogeneous catalysts with extended lifetimes. Unambiguous identification of catalytic poisoning species requires experimental methods simultaneously delivering accurate information regarding adsorption sites and adsorption geometries of adsorbates with nanometer-scale spatial resolution, as well as their detailed chemical structure and surface functional groups. However, to date, it has not been possible to study catalytic sulfur poisoning of metal/metal-oxide interfaces at the nanometer scale without sacrificing chemical definition. Here, we demonstrate that near-field nano-infrared spectroscopy can effectively identify the chemical nature, adsorption sites, and adsorption geometries of sulfur-based catalytic poisons on a Pd(nanodisk)/Al2O3 (thin-film) planar model catalyst surface at the nanometer scale. The current results reveal striking variations in the nature of sulfate species from one nanoparticle to another, vast alterations of sulfur poisoning on a single Pd nanoparticle as well as at the assortment of sulfate species at the active metal-metal-oxide support interfacial sites. These findings provide critical molecular-level insights crucial for the development of long-lifetime precious metal catalysts resistant toward deactivation by sulfur

Ontology-based end-user visual query formulation: Why, what, who, how, and which?

Value creation in an organisation is a time-sensitive and data-intensive process, yet it is often delayed and bounded by the reliance on IT experts extracting data for domain experts. Hence, there is a need for providing people who are not professional developers with the flexibility to pose relatively complex and ad hoc queries in an easy and intuitive way. In this respect, visual methods for query formulation undertake the challenge of making querying independent of users’ technical skills and the knowledge of the underlying textual query language and the structure of data. An ontology is more promising than the logical schema of the underlying data for guiding users in formulating queries, since it provides a richer vocabulary closer to the users’ understanding. However, on the one hand, today the most of world’s enterprise data reside in relational databases rather than triple stores, and on the other, visual query formulation has become more compelling due to ever-increasing data size and complexity—known as Big Data. This article presents and argues for ontology-based visual query formulation for end-users; discusses its feasibility in terms of ontology-based data access, which virtualises legacy relational databases as RDF, and the dimensions of Big Data; presents key conceptual aspects and dimensions, challenges, and requirements; and reviews, categorises, and discusses notable approaches and systems