scholarly journals Behavior of Steel Plate Girders with Deep Section under Dynamic Effect

2020 ◽  
Vol 10 (1) ◽  
pp. 207-209
Keyword(s):  
Cross Section ◽  
Dynamic Effect ◽  
Welding Distortion ◽  
Minimum Mass ◽  
Plate Girders ◽  
Section Modulus ◽  
Web Stiffeners ◽  
Assembly Procedure ◽  
The Cost ◽  
The Web

Having a minimum mass, equal-sized flanges and no web stiffeners is the most economical plate girder to fabricate. As with rolled I-sections, for a given section modulus a section with a greater depth will have a lower mass than one with a smaller depth, except in some instances where a thicker web is required in the deeper section. A wider flange plate to resist the buckling tendency may be necessary to use, when the compression flange is laterally unrestrained, but this will add to the cost because of the more difficult assembly procedure. In order to arrive at a minimum-mass cross section as much as possible of the material should be located in the flanges and as little as possible in the web, consistent with shear requirements. There is usually an advantage, however, in using a somewhat thicker web in order to reduce welding distortion, or to avoid the use of or number of stiffeners. It can be shown that for a given web depth to thickness ratio the minimum-mass cross section is that in which the area of the two flanges combined equals that of the web, i.e. 2Af = Aw.An important consideration in cost reduction is the use of preferred plate widths and thicknesses for the flange and web elements.

Bridge Girders with Corrugated Webs

2000 ◽  
Vol 1696 (1) ◽  
pp. 162-170 ◽  
Author(s):  
Mohamed Elgaaly ◽  
Anand Seshadri ◽  
Roberto Rodriquez ◽  
Sherif Ibrahim
Keyword(s):  
Moment Capacity ◽  
Design Recommendations ◽  
Plate Girders ◽  
Analytical Results ◽  
Corrugated Webs ◽  
Shear Buckling ◽  
The Moment ◽  
The Cost ◽  
Web Plates ◽  
The Web

In plate girders, the use of corrugated webs permits the use of thin web plates without stiffeners, which reduces the cost of beam fabrication and improves fatigue life. Experimental and analytical studies on the behavior of girders with corrugated webs were conducted that have led to design recommendations. For girders with corrugated webs subjected to shear, it was noted from the experimental as well as the analytical results that failure of the web occurs because of local or global shear buckling, which depends on the corrugation configuration. For girders with corrugated webs subjected to uniform bending, the failure was due to yielding and vertical buckling of the compression flange into the web. The test and analytical results indicate that the web offered negligible contribution to the moment-carrying capacity of the beam, and the ultimate moment capacity may be calculated on the basis of the flange yielding, ignoring any contribution from the web. The behavior of girders with corrugated webs under in-plane compressive edge loads applied directly on the top flange was investigated, and design recommendations are made. Tests to examine the behavior of girders with corrugated webs under repeated loads are few. The results from the available tests are reported and compared with the results from test on conventionally stiffened girders with flat webs.

Classification of the factors forming the cost of the web-site

2017 ◽  
Vol 31 (2) ◽  
pp. 82-89
Author(s):  
E. S. Epifanov
Keyword(s):  
Web Site ◽  
Internet Site ◽  
Advantages And Disadvantages ◽  
Major Factors ◽  
The Cost ◽  
The Web

This article presents a classification of major factors that shape the cost of Internet site. Also discusses the limitations in determining the objectives of the web site; advantages and disadvantages of different factors.

scholarly journals Development of Filters with Minimal Hydraulic Resistance for Underground Water Intakes

2020 ◽  
Vol 6 (5) ◽  
pp. 919-927
Author(s):  
A. A. Akulshin ◽  
N. V. Bredikhina ◽  
An. A. Akulshin ◽  
I. Y. Aksenteva ◽  
N. P. Ermakova
Keyword(s):  
Hydraulic Resistance ◽  
Cross Section ◽  
High Performance ◽  
Underground Water ◽  
Performance Characteristics ◽  
Design Stage ◽  
Performance Loss ◽  
Filter Performance ◽  
Optimal Section ◽  
The Cost

The development of modern structures of water wells filtering equipment with enhanced performance characteristics is a vital task. The purpose of this work was to create filters for taking water from underground sources that have high performance, long service life, quickly and economically replace or repair in case of performance loss. The selection of the filter device must be made taking into account all the geological features of the aquifers, the performance characteristics of the filter devices and the size of the future structure. Filter equipment designs for water intake wells have been developed in this study. These filters have low hydraulic resistance, high performance and are easy to repair. This article presents the dependency of flow inside the receiving part of the well, the dependence of filter resistance at various forms of the cross section of the filter wire and the selected optimal section. The paper proposes a method for selecting the optimal cross-section of the filter wire used in the manufacture of a water well filter. The proposed structures of easy-to-remove well filters with increased productivity allow replacing the sealed well filter with a new one easily, reducing capital and operating costs, and increasing the inter-repair periods of their operation. Based on the presented method, examples are given for selecting the parameters of the filter wire cross-section. The above calculations showed that the use of the hydraulic resistance criterion at the design stage of underground water intakes can significantly reduce the cost of well construction. Studies have found that the minimum hydraulic resistance to ensure maximum filter performance is achieved when using filter wire teardrop and elliptical shapes.

Democracy, Elections, and Constitutionalism in Africa

2021 ◽  
Keyword(s):  
Cross Section ◽  
Nation Building ◽  
Legal Traditions ◽  
Design Systems ◽  
The Cost ◽  
Opposition Parties

This book is the outcome of the sixth Stellenbosch Annual Seminar on Constitutionalism in Africa (SASCA). The theme of the seminar was ‘Democracy, elections and Constitutionalism in Africa.’ The participants examined how the fledgling foundations of African constitutionalism could sail through the stormy seas of authoritarian revival and prevent the democratic recession spiralling into a depression. They examined a number of intricate issues concerning the role of elections in fostering democracy and constitutionalism. Some of the issues looked at included how we could design systems that will ensure that elections on the continent are genuinely competitive and reflect a real contest between competing approaches to nation-building and not a contest between perceived enemies? Or again, how we could reduce the cost of losing an election and encourage incumbents and opposition parties to accept defeat and continue to play by the rules of the democratic game? Whilst there are no easy and obvious answers to the numerous questions that arise, they nevertheless are important and urgent issues that need to be seriously interrogated. This is because, even if constitutionalism and democracy may not be working well today in Africa, there is no better alternative. The chapters in this book have been written by attendees from the seminar and cover a cross section of the continent’s regions and legal traditions.

Morpheus Web Testing: A Tool for Generating Test Cases for Widget Based Web Applications

2021 ◽  
Author(s):  
Romulo de Almeida Neves ◽  
Willian Massami Watanabe ◽  
Rafael Oliveira
Keyword(s):  
User Interfaces ◽  
Web Application ◽  
Web Applications ◽  
Test Cases ◽  
Code Coverage ◽  
Web Testing ◽  
The Cost ◽  
Software Lifecycle ◽  
The Web

Context: Widgets are reusable User Interfaces (UIs) components frequently delivered in Web applications.In the web application, widgets implement different interaction scenarios, such as buttons, menus, and text input.Problem: Tests are performed manually, so the cost associated with preparing and executing test cases is high.Objective: Automate the process of generating functional test cases for web applications, using intermediate artifacts of the web development process that structure widgets in the web application. The goal of this process is to ensure the quality of the software, reduce overall software lifecycle time and the costs associated with tests.Method:We elaborated a test generation strategy and implemented this strategy in a tool, Morpheus Web Testing. Morpheus Web Testing extracts widget information from Java Server Faces artifacts to generate test cases for JSF web applications. We conducted a case study for comparing Morpheus Web Testing with a state of the art tool (CrawlJax).Results: The results indicate evidence that the approach Morpheus Web Testing managed to reach greater code coverage compared to a CrawlJax.Conclusion: The achieved coverage values represent evidence that the results obtained from the proposed approach contribute to the process of automated test software engineering in the industry.

Nep-Endotrainer: A cost-effective home-made laparoscopic simulation tool

2021 ◽  
Vol 23 (2) ◽  
pp. 52-55
Author(s):  
Uttam Laudari ◽  
Deepak Mahat ◽  
Rosi Pradhan ◽  
Suyog Bhandari ◽  
Deepak Raj Singh
Keyword(s):  
Laparoscopic Surgery ◽  
Mobile Phones ◽  
Cost Effective ◽  
Simulation Tool ◽  
Drilling Machine ◽  
Web Camera ◽  
The Cost ◽  
Training Modules ◽  
Established Treatment ◽  
The Web

Introduction: Laparoscopic surgery is an established treatment modality worldwide. Opportunities to acquire this skill using expensive simulation at workplace are not always feasible due to cost, time and accessibility constraints. Nep-Endotrainer is a cost effective homemade laparoscopic simulation tool built in Nepal. Methods: Nep-Endotrainer was built using plastic manikins easily available in market. Nine apertures were created with a drilling machine, four on each side of umbilicus and one at the epigastric region. These apertures were covered by thick piece of rubber of vehicle tire with apertures in them. Logitech® C270 HD webcam was fixed interiorly with metal screws. The base of the manikin was fixed to a wooden board with hinge joint. Five different interchangeable training modules were assembled in 10×10 cm2 size wooden boards. The LED light was fixed interiorly near the web camera. The camera USB can be easily connected with laptops, tablets and mobile phones. We used discarded hand instruments from laparoscopic centers to reduce the cost of the endotrainer. Conclusion: Nep-Endotrainer is accessible to any personal budget and can be readily constructed. It allows more frequent practice at home, outside the venue and hours of surgical departments.

E-Impresa

2010 ◽  
pp. 470-485
Author(s):  
Habib Sedehi
Keyword(s):  
Sustainable Growth ◽  
Strategic Decisions ◽  
Whole Process ◽  
On Line ◽  
Business Game ◽  
Break Even Point ◽  
The Cost ◽  
The Web

Electronic commerce, marketing on line, and network economy are today’s keywords of (possible) success. But how many managers effectively know about the cost and benefits of starting to sell their products and services through the Web? How much they should invest at the beginning and how long does it takes to have a break-even point of their investment? In order to give support for better understanding the process of the Web marketing and to have more elements to decide to “dive” or not in this virtual world a System Dynamics (SD) model (Forrester J.W. 1961, 1971, 1980), has been developed. The model has the aim to support strategic decisions for SME involvement in e-Commerce, pointed out to guarantee sustainable growth and medium-long term success. The project e-Impresa1 analyses the whole process of the investment in building and maintaining a web site, taking into account the main variables of E-commerce. Through a case study, a SD business game model has been developed. The model gives the opportunity to users to evaluate different what-if analysis through the simulation period time (2 years) at each model step time (4 weeks). This chapter will explain the overall architecture of the model and will present some results of use of the model in different conditions.

scholarly journals The creation of a computational model of corrugated beams using the author’s program “GOPRO”

2018 ◽  
Vol 251 ◽  
pp. 04007 ◽  
Author(s):  
Vadim Alpatov ◽  
Alexey Lukin ◽  
Irina Laguta
Keyword(s):  
Finite Element ◽  
Computational Model ◽  
Cross Section ◽  
Geometrical Shape ◽  
File Format ◽  
Element Mesh ◽  
Automated Generation ◽  
Numerical Studies ◽  
Geometrical Scheme ◽  
The Web

The program «Gofro» is intended for the automated generation of data on the geometrical scheme of the beam with corrugated or plane web for further use in design complexes. The program has got a window interface, and it consists of one module for the input of feed da-ta, for calculation and for the display of its results in txt file format. The program offers a possibility to choose the outline of the structure, the profile of the web, the type of cross-section, and to set other parameters of the structure. When building up the model with the help of the author program «Gofro» and GMSH preprocessor for the automatic genera-tion of finite element mesh, the correctness of geometrical shape of elements is monitored by the algorithms that are input in the preprocessor. The author compares the time re-quired to create the models using the author program and GMSH preprocessor and using the standard resources of «Lira» software system. The authors performed numerical studies of various I-beams created in the program «GOPRO».

scholarly journals Treatment of Myeloproliferative Disorders With Hydroxyurea: Effects on Red Blood Cell Geometry and Deformability

Blood ◽  
1998 ◽  
Vol 91 (10) ◽  
pp. 3986-3991 ◽  
Author(s):  
K. Gunnar Engström ◽  
Eva Löfvenberg
Keyword(s):  
Cross Section ◽  
Blood Cells ◽  
Flow Resistance ◽  
Myeloproliferative Disorders ◽  
Initial Deformation ◽  
Cell Geometry ◽  
Membrane Area ◽  
Section Modulus ◽  
Rbc Membrane ◽  
Before And After

Abstract Hydroxyurea (HU) is used in suppressing the bone marrow and producing fetal-like red blood cells (RBCs). These RBCs are large in size and may theoretically disturb the microcirculation. In five patients with myeloproliferative disorders (MPD), the RBC geometry and deformability were analyzed before and after 6 to 8 months of HU treatment. In untreated MPD, the RBC geometry and filterability was normal. After HU, the RBC membrane area increased 24% and the cell volume increased 39% (P < .005). This change resulted in a 12% increase in the minimum cylindrical diameter (MCD). From a static bending model of initial deformation, the RBC diametrical cross-section had a significantly increased section modulus. However, this increase in profile stiffness was compensated for by its larger projected cell area and, thus, pressure load on the RBC corpuscle. The resulting resistance to initial deformation therefore remained unchanged after HU. These findings were tested experimentally; with 3-μm filter membranes, HU treatment caused a significant increase in flow resistance (P < .02), in accordance with MCD. However, with 5-μm pores, no difference was seen, again in consonance with the theoretical findings of initial deformation. Because most capillaries are larger than 3 μm, we suggest that HU is acceptable from a perspective of cellular microrheology.

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