Stability is one of the most critical problems in the design of welded metal structures, since in many cases instability causes failure or collapse of the structures. The present study aims to show the minimum mass design procedure for welded steel box columns loaded by a compression force. The normal stresses and overall stability are calculated for pinned columns. The dimensions of the box columns are optimized by using constraints on global stability, local buckling of webs and flanges. Different design rules and standards are compared: Eurocode 3, Japan Railroad Association, American Petroleum Institute, and American Institute of Steel Construction. The calculations are made for different loadings, column length and steel grades. The yield stress varies between 235 and 690 MPa. Optimization is carried out using the generalized reduced gradient method in Excel solver. Cost calculations and comparisons show the most economical structure.
. Specifically, we are interested in the standard selective catalytic reduction (SCR) of NO by NH 3 ,
on metal-exchanged zeolites, Fe-ZSM-5 or Cu-ZSM-5. This reaction, reviewed recently in detail by Brandenberger et al. [ 5 ], is of high current interest due to
a simple reaction scheme of N 2 O decomposition running in the presence of oxygen on single Fe atoms [ 3 ] and a much more complex scheme of standard selective catalytic reduction (SCR) of NO by NH 3 ,
Authors:Amahjour Narjisse and Khamlichi Abdellatif
models following the RANS approach that have been extensively used one finds: standard k − ϵ and S S T k − ω [ 28–33 ]. Considering hilly terrain, the above mentioned closure models have been used to predict wind flow in the ABL around hills. Due to
The STEP NC system that replaces the ISO 6983 standard has been under development more than 10 years. However, just a few control developers find alternatives in the new standard that includes several completed modules. The paper shows in which role the industrial companies could use a new generation NC standard. The paper concludes the parameters that support the setting up of a mathematical model for a place-centered application with the help of case studies. The expected powerful opportunities of the application of a new generation NC standard are described with the help of case studies.
In different Comfort Standards, for different building functions the requirements for summer and also for winter period differ. The operative temperature is one of these parameters, which in different Comfort Standards for summer-winter period specifies the building's comfort category.
This paper presents the results of measurement of the operative temperature in PASSOL laboratory with different heat storage and using night ventilation.
Authors:Olena Yakymchuk, Dmytro Yakymchuk, Nataliia Bilei-Ruban, Iryna Nosova, Serhiy Horiashchenko, Kostyantyn Horiashchenko, Tetyana Kisil, and Viacheslav Tuz
experimental research of headwear details forming of difficult spatial non-standard form. 3 Results and discussion To expand the technological capabilities of headwear details forming from fabrics an experimental equipment was prepared, which allows to simulate
Authors:Muaayed F. Al-Rawi and Muhanned F. Al-Rawi
in an era of personal computers and most students now own a computer, speed and performance notwithstanding. Since a soundcard is standard on most computers, it would be a noble idea to make use of the inherent digital signal processor to construct an