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Open access

J. O. Hamed, O. O. Ogunleye and C. A. Osheku

-100. 6. Yang R., An H., Tan H., Combustion and Thermal Decomposition of HNIW and HTPB/HNIW Propellants with Additives, Combustion and Flame, 135 (2003), 463-473. 7. Singh S., Raina C. S., Bawa A. S., Sexena D. C., Sweet potato-based pasta product: optimization of ingredient levels using response surface methodology, International Journal of Food Science and Technology 38 (2003). 1-10. 8. Langlet A., Wingborg N., Ostmark H., A New High Performance Oxidizer for Solid Propellants, International Journal of Energetic Materials and Chemical

Open access

M. Brzeziński, A. Stawowy and R. Wrona

Abstract

Systemic approach to design of factories requires that engineering, organisational and economic aspects should be considered concurrently. That prompts the need to develop a solution, based on the state-of-the-art IT technologies, to enable us to solve the problems associated with foundry production planning. The paper outlines a methodology of creating the simulation model of a virtual foundry, as a tool for foundry design. An integrative approach is suggested for development of a complete foundry model, enabling the design of more efficient production systems. The underlying principles of such models are discussed, the basic stages involved in the methodology are outlined and the range of its applicability is defined.

Open access

Renata Patyńska

emission system, calculation of emissions for the last year using the indications of the OECD/IPCC methodology and given methodologies of current information updating, National Fund of Environmental Protection, Warsaw, 1994, (nonpublished). [4] GAWLIK L., GRZYBEK I., Methodology of estimation of methane emissions connected with coal exploitation in Poland, Mineral Raw Materials Management, Vol. II, Booklet 3, 1995. [5] GAWLIK L., GRZYBEK I., Investigation results and recommendations for uncertainty reduction and clarity improvement of

Open access

Mathias Flansbjer and Jan Erik Lindqvist

Abstract

This project focused on how the cracking process in concrete is influenced by both the micro and meso structures of concrete. The aim was to increase knowledge pertaining to the effect of critical parameters on the cracking process and how this is related to the material’s macroscopic properties. A methodology based on the combination of different experimental methods and measuring techniques at different scales was developed. Crack propagation during tensile loading of small-scale specimens in a tensile stage was monitored by means of Digital Image Correlation (DIC) and Acoustic Emission (AE). After testing, crack patterns were studied using fluorescence microscopy.

Open access

P. Raczyński and K. Warnke

Abstract

The main pipelines, like many engineering structures, are subject to high operational safety standards. The safety of their operation is supervised by various institutions from the operator, including supervisors such as the Office of Technical Inspection. Safe operation requires knowledge of their technical condition and trends. One of the important sources of information on the condition of pipelines is their periodic inspection carried out with so-called smart pigs. As a result of the inspection, the operator expects the following questions to be answered: what is the condition of the pipeline examined; where and what metal losses are occurring in its construction; what are the hazards causing these damages for the safety of the pipeline operation; what is the rate of increase in the size of metal losses in the pipeline wall. This article presents technical solutions and methodology to answer the above questions.

Open access

Ż. A. Mierzejewska and W. Markowicz

Abstract

Rapid prototyping technology (RP), based on designing and computer aided manufacturing, is widely used in traditional branches of industry. Due to its ability to accurately and precisely manufacture designed elements of various dimensions and complicated geometry, this technology is more and more frequently applied in the field of biomedical engineering. Selective laser sintering (SLS) is a universal RP technique, utilizing a laser beam to sinter powdered materials and create three-dimensional objects. Data for producing parts for tissue replacement come from medical imaging capabilities and digital presentation of test results. This paper presents the following: general classification of RP methods, the concept and methodology of performing laser sintering, sintering mechanisms, and the application of elements manufactured using this technology in biomedical engineering, particularly for the production of scaffolds used in tissue cultures, skeletal and dental prostheses in dental implantation, manufacturing of custom-made implants that are individually adjusted to the patient, and for production of training models on which a team of surgeons can train a surgical technique.

Open access

O.O. Ogunleye, A.G. Adeniyi and M.O. Durowoju

Abstract

The effects of chloride concentration, creviced scaling factor and immersion time on the percentage area and maximum depth of attack for Type 304 stainless steel (SS304) in chloride solutions were investigated. The crevice assembly comprised of coupon (SS-304), polytetrafluoroethylene (crevice former) and fasteners (titanium bolt, nut and washers). The full immersion tests were based on ASTM G-78 using full factorial design to study the effects of chloride concentration (1.5, 3.0 and 4.5 w/w%), crevice scaling factor (8, 16 and 24) and immersion time (15, 30 and 45 days) on the percentage area of attack (Y1) and maximum depth of attack (Y2) of SS-304. Data obtained was used to develop and optimize the models of Y1 and Y2 in terms of the three factors using Response Surface Methodology (RSM). The R2 of Y1 and Y2 were 0.98 and 0.91, respectively. The minimum Y1 (5.63%) and Y2 (3.32×10−7 mm) were obtained at 4.5% chloride concentration, 20 scaling factor and 15 days immersion time. The predicted optimal conditions agreed with the experimental results for validation with a maximum absolute relative error of 5.75%.

Open access

Mohammad H. Baghban, Mahdi Kioumarsi and Sotirios Grammatikos

pastes”, Materials and Structures , Vol. 46, No. 9, 2013, pp. 1537-1546. 4. Monteiro P J M, “A note on the Hirsch model,” Cement and Concrete Research , Vol. 21, 1991, pp. 947-950. 5. Hashin Z, Shtrikman S, “A Variational Approach to the Theory of the Effective Magnetic Permeability of Multiphase Materials,” Journal of Applied Physics , Vol. 33, No. 10, 1962, pp. 3125-3131. 6. Bezerra M A, Santelli R E, Oliveira E P, Villar L S, Escaleira L A, “Response surface methodology (RSM) as a tool for optimization in analytical chemistry,” Talanta , Vol

Open access

W. Szymański and M. Lech-Grega

References 1. Kula E., Weiss V.: Residual Stress and Stress Relaksation. Plenum Press New York,1982. 2. Kokosza A.: Application of the method magnetic Barkhausen noise measurement to evaluate the stress in steels, [in Polish]. Seminar on Methodological problems of residual stress measurement, Poznań 1994. 3. Noyan I.C., Cohen J.B.: Residual stress measurement by diffraction and interpretation, Springer- Verlag New York, 1987. 4. Pszonka A., Ziaja J.: X-ray stress measurement methods [in Polish

Open access

W. Raczkiewicz

high-strength steel fiber-reinforced concrete, Construction and Building Materials, 18 (9), (2004), 669–673. 5. Goszczyński S., Raczkiewicz W.: Methodology Research axial compression specimens fibroconcrete process variable loads (in Polish), Budownictwo z. 1-B/2007 Wydawnictwo Politechniki Krakowskiej, 2007. 6. Raczkiewicz W.: Shrinkage of concrete - Features important due to the design of concrete structures (in Polish), Przegląd Budowlany, 2 (2012), 43-46. 7. Eurocode 2: Design of concrete structures – Part 1-1: General rules and rules for