Commutators, Lefschetz fibrations and the signatures of surface bundles

We construct examples of Lefschetz fibrations with prescribed singular fibers. By taking differences of pairs of such fibrations with the same singular fibers, we obtain new examples of surface bundles over surfaces with non-zero signature. From these we derive new upper bounds for the minimal genus of a surface representing a given element in the second homology of a mapping class group.Comment: 20 pages, 7 figures, accepted for publication in Topolog

Impact of Autonomous Vehicles on Parking Spaces

The United States has an enormous supply of parking and with the appropriation of Autonomous vehicles, the interest for these spaces could change drastically. Parking is among the most pervasive land utilizes involving up to 31% of urban territory. With completely automated vehicles expected on the customer advertise by 2020, the $30 billion leaving industry will encounter gigantic changes as autos develop. The purpose of this paper is to analyse how the parking and garage spaces can be utilized after the implementation of automated vehicles in every household. Analysis has been conducted about different households in Ypsilanti Township using Zillow application which includes the address, area of the house, parking area and year in which it is built. Results are based on the analysis conducted on the houses and the impact of the autonomous vehicles on their parking space

Composing a high-frequency financial conditions index and the implications for economic activity

In this study, we construct an index using high-frequency data related to financial markets and intermediation services in Turkey, called the High-Frequency Financial Conditions Index, employing alternative statistical techniques for the period from 2006 to 2020. We also analyze the informative nature of the indices constructed with respect to the course of economic activity. Additionally, we perform a detailed empirical analysis of the relationship between financial conditions and growth tendencies. The results of the time-series analysis show that the series constructed are quite informative for monitoring economic activity. In this context, probit model estimations indicate that the index constructed can be used as an early indicator to predict “loss of momentum” episodes in economic growth, taking the lead-lag relationship into consideration. When a similar methodology is applied to emerging market economies, indices exhibit a high level of comovements with growth indicators. Panel vector autoregression estimation shows that, after country-specific characteristics are controlled for, a shock to financial conditions facilitates a significant response in the growth rates of emerging market economies. In terms of policy making, the indices can contribute to a better understanding of the financial outlook and its interaction with economic activity.Publisher PDFPeer reviewe

Spontaneous internal jugular vein thrombosis: A case report

Internal jugular vein thrombosis (IJVT) is an elusive vascular disease that is rarely seen, with potentially lethal complications such as sepsis and pulmonary embolism. Spontaneous IJVT is considered when no apparent predisposing cause of thrombosis is present. A previously healthy, 31-year-old woman presented to the university-based emergency department because of painless swelling in the right anterior side of her neck. Physical examination revealed a painless, soft and immobile mass in the right anterior side of her neck beneath the sternocleidomastoid muscle, without hyperemia or local heat. On ultrasonographic examination, a hyperechogenic mass was visualized around the thoracic entrance of the right internal jugular vein, which was suggestive of a thrombus. The patient was administered intravenous antibiotic and low-molecular-weight heparin followed by oral coumadin as anticoagulant therapy. Her complaints were relieved within 5 days. She was completely well after 6 months. Venous thrombosis generally results from impaired blood flow locally or systemically that leads to activation of coagulation. Primary care physicians should sustain a high index of suspicion in patients who present with undiagnosed swelling in the neck, or other signs and symptoms attributed to IJVT. © 2010 Elsevier. All rights reserved

Evaluating the use of Drones in the area of Transportation/Construction

Drones are proving out as a valuable tool and growing quickly in the world of technological advances. The applications of these vehicles are spreading widely in the areas of remote sensing, real time monitoring, goods delivery, security, defense, surveillance, infrastructure inspection. Although, the intent behind creating this tool was remote sensing. Smart drones will be the next big innovation and modification, which would have much wider applications especially in the field of infrastructure where it can reduce risks and lower costs. Current direct evaluation techniques are tedious, and the information caught is frequently not led in a precise manner with the areas tested not being geographically correct and the resulting reports being delivered past the point of no return. These were the reasons, which have increased the demand and usage of unmanned vehicles. In this research paper, we present critical review of main advancements of Drones in the area of transportation and agriculture. We present all the research related to civil applications in those areas and challenges including traffic monitoring, Bridge condition assessment, Roadway asset detection and many other applications related to infrastructure inspection enhancement. The paper also contributes with a discussion on the opportunities, which are opened, and the challenges that need to be addressed. Findings from the case studies, it is reported that around 25% of the bridges in united states are deficient and need continuous monitoring for enhancements to prevent any hazard. Unmanned vehicles could be a great help in monitoring these bridges and other important components of transportation, which can efficiently minimize the cost as well as the time spent on inspection for each of this component, as manual inspection requires labor and time which would be subsequently reduced by incorporating the usage of drones in the area of transportation

Capacity Increase for Existing Steel Bridges Using Prestressed Cables

In the present study, a practical approach is proposed for geometric nonlinear analysis of existing steel bridges. The approach is defined by finite element displacement direct rigidity procedure, which is based on an iterative procedure. Tangent rigidity matrix is used for cable truss and/or framed steel structures formed by finite elements. Hence, effects of prestressed cables in system rigidity can be taken into account in the analyses. Moreover, stressing effects on cables are taken into account with equivalent temperature change. The research has three main parts. In the first part, prestressed cables are investigated for capacity increase for steel bridges. In the second part, an iterative procedure is proposed for existing steel bridges that can be used for geometric nonlinear analysis. In the third part, a representative bridge is modeled and analyzed. In the model, first, the representative model is analyzed as it is existing form and then, it is analyzed with prestressed cables in two different forms. So, three different results are investigated for their structural behaviors. In the analyses, geometric nonlinear behavior is investigated and results are evaluated. As a result of the study, capacity change by using stressed cables is defined for existing bridges

Investigation of Tractor Dealer Profile in Aydın Province

Tractor sales and usage varies depending on many factors like of the region and the products. The main purpose of this study is to investigate of sales and marketing profiles of tractor dealers operating in Aydın Province. Survey form was conducted through face to face interviews to authorized tractor dealers operating in Aydın Province (14 total). Data about firms (number of employees, brand preferences, customer portfolio, marketing campaigns, marketing calanders, approach to the expected scrap reduction and customer’s brand expectations) were obtained with questionnaires. Half of the dealers are selling the tractors produced by domestic firms. The brands ranking which are most preferred by dealers, first is New Holland (42%) and the second is Turk-Fiat (35%). Dealers stated that, the most important criteria for customers' preferences are engine parts and price and the most intense period for sales is spring. Results of this study are, state-sector cooperation must be developed in order to increase competitiveness of the Turkish firms in the tractor market, modern marketing tecniques must be used, consumer behaviors must be determined and the firms which makes sales according to these factors must improve themselves for the future of the tractor industry. Keywords: Advertising, Dealers Profile, Marketing, Sales, Tracto