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Abstract

Nowadays, digital technology and measurement are improving to measure some systems in accurate conditions without errors. From these improvements and developments, it is necessary to analyse performances and condition of bicycle and biker before high level computations. In this experimental investigation, a high quality and very light bicycle and a well-equipped trained biker were trained to test the system with different road and region conditions. The purpose of this investigation is to predict unwanted conditions of bicycle before computations and activity. Otherwise, this kind of experimental trained testing will give some information from unwanted bicycle accidents. Moreover, in this experimental work, a power meter and measurement instrument with sensors are used to measure real time parameters. As can be concluded from experimental results and the analysis, the proposed work has a good design and analysis for good material bicycles. The displacement analysis is also outlined with load of a 63 kg biker.

Open access

Abstract

Presence of pathogenic strains of Escherichia coli in foodstuffs may pose a health risk for a consumer. Therefore, knowledge on the effect of environmental factors on the growth ability of E. coli is of great importance. In this work, the effect of incubation temperature (6–46 °C) and the combined effect of temperature and water activity (0.991–0.930) on the growth dynamic of E. coli PSII were analysed. Based on the growth curves obtained, growth parameters were calculated by using the Baranyi D-model. Growth parameters were further analysed in secondary phase of predictive modelling. Using the CM model that describes the effect of combined factors, cardinal values (T min = 4.8 ± 0.4 °C, T opt = 41.1 ± 0.8 °C, T max = 48.3 ± 0.9 °C, a wmin = 0.932 ± 0.001, and a wopt = 0.997 ± 0.003) for the isolate were calculated. Under optimal conditions, the specific growth rate is µ opt = 2.84 ± 0.08 h−1. The results obtained may contribute to the assessment of the risk associated with the possible E. coli presence in raw materials and to the search for preventive measures with defined degree of accuracy and reliability.

Open access

Abstract

A numerical simulation procedure is presented to predict residual stress states in multi-pass welds in oil transportation pipes. In this paper, a two-dimensional thermo-mechanical finite element model is used to calculate the temperature distribution, hardness, and the distribution of residual stresses during multi-pass welding of pipes of dissimilar metals and varying thicknesses. In this model, the temperature dependence of the thermal and mechanical properties of the material was considered. The present model was validated using the hardness measurement. Good agreement was found between the measurement and the numerical simulation results. The simulated result shows that the two-dimensional model can be effectively used to simulate the hardness test and predict the residual stress in the pipe weld. The simulation results and measurements suggest that the model with moving heat source can obtain a good prediction of residual welding stress. Both the two-dimensional and the three-dimensional modeling can be used to estimate the residual stresses in different weld regions and help saving time.

Open access

Abstract

A numerical simulation procedure is presented to predict residual stress states in multi-pass welds in oil transportation pipes. In this paper, a two-dimensional thermo-mechanical finite element model is used to calculate the temperature distribution, hardness, and the distribution of residual stresses during multi-pass welding of pipes of dissimilar metals and varying thicknesses. In this model, the temperature dependence of the thermal and mechanical properties of the material was considered. The present model was validated using the hardness measurement. Good agreement was found between the measurement and the numerical simulation results. The simulated result shows that the two-dimensional model can be effectively used to simulate the hardness test and predict the residual stress in the pipe weld. The simulation results and measurements suggest that the model with moving heat source can obtain a good prediction of residual welding stress. Both the two-dimensional and the three-dimensional modeling can be used to estimate the residual stresses in different weld regions and help saving time.

Open access

Abstract

Energy storage on grid level is still a critical issue. Inventions related to development and control of smart buildings, including integrated solar systems can be easily realized by smart control of building management including storage. At buildings, which have high heat capacitance the part of the stored heat can be used for grid stabilization. This means the grid can be balanced with well-set up heating/cooling strategy and well-scheduled timetable via intelligent control of buildings. A possible solution is introduced in this paper, where the surplus production is used for overcooling the building, while the building thermodynamic properties are making it possible to store this amount of energy for days. This paper analyses a cost-effective solution of grid energy storage through a case study.

Open access
Pollack Periodica
Authors: Istvan Ervin Haber, Gergely Bencsik, Basma Naili, and Istvan Szabo

Abstract

Energy storage on grid level is still a critical issue. Inventions related to development and control of smart buildings, including integrated solar systems can be easily realized by smart control of building management including storage. At buildings, which have high heat capacitance the part of the stored heat can be used for grid stabilization. This means the grid can be balanced with well-set up heating/cooling strategy and well-scheduled timetable via intelligent control of buildings. A possible solution is introduced in this paper, where the surplus production is used for overcooling the building, while the building thermodynamic properties are making it possible to store this amount of energy for days. This paper analyses a cost-effective solution of grid energy storage through a case study.

Open access

Abstract

Skidmore, Owings & Merrill Limited Liability Partnership as one of the best ‘localized’ overseas design companies in China, has participated in more than ten large-scale urban design projects in Wuhan, which has greatly changed the urban image and architectural style of Wuhan. Its space model of ‘grid road system + high-rise building’ replaces the traditional urban pattern of ‘street + residence’, causing huge cultural conflicts and historical rupture. Based on the planning of Wuhan Hanzheng street as an example, this paper attempts to uncover the cause of formation, the motivation mechanism of ‘grid road system + high-rise buildings’ space model, and to explore how Chinese cities realize the urban modernization with Chinese characteristics.

Open access

Abstract

Skidmore, Owings & Merrill Limited Liability Partnership as one of the best ‘localized’ overseas design companies in China, has participated in more than ten large-scale urban design projects in Wuhan, which has greatly changed the urban image and architectural style of Wuhan. Its space model of ‘grid road system + high-rise building’ replaces the traditional urban pattern of ‘street + residence’, causing huge cultural conflicts and historical rupture. Based on the planning of Wuhan Hanzheng street as an example, this paper attempts to uncover the cause of formation, the motivation mechanism of ‘grid road system + high-rise buildings’ space model, and to explore how Chinese cities realize the urban modernization with Chinese characteristics.

Open access

Abstract

Fly ash-based geopolymer fine aggregate is a potential replacement material for the natural river sand as it has similar physicochemical properties. This paper reports the experimental investigation of a study conducted using this fine aggregate in concrete with a focus on the properties of fresh and hardened concrete. The geopolymer fine aggregate was developed by air curing process and oven curing method. The oven curing method yielded relatively better mechanical properties in concrete specimens. The oven curing results in better behavior at later age also. Laboratory tests were conducted to ascertain the fresh concrete density, slump value, hardened concrete density, compressive strength, tensile strength, and flexural strength of the concrete specimens. The microstructure of the concrete specimens was analyzed using scanning electron microscope which indicated the agglomeration of the fly ash particles with few voids demonstrating the higher water adsorption capacity of the same. The unreacted particles noted in the microstructure later tend to merge with the lime obtained from the hydration of cement so as to develop improved later age mechanical strength. The results on mechanical properties of the concrete indicate much similar results to that of the concrete developed with the normal river sand, which confirms that the geopolymer sand is an ideal replacement choice for natural river sand.

Open access

Abstract

Rail monitoring is an important activity which aims to preserve the safety and availability of railways. According to statistics, the primary cause of railway accidents is due to transverse defects that occur in the rail head. These special defects develop generally in a plane orthogonal to the rail running direction. The detection of these defects is a priority to increase the safety of rail transportation. Rail control monitoring techniques mostly rely on infrared thermography, eddy currents, air-coupled acoustic sensors, and ultrasounds. The present research studies the rail diagnosis by means of a non-contact device. The focus is on ultrasonic based methods where excitation is generated by thermal elastic coupling following laser irradiation of the rail head. For the reception of echoes, a special ultrasound sensor was used. In order to sense defects, phased array elements, which use multiple transducers and electronic time delays, are used to increase and to focalise the signal intensity. Flaws that have a moderate extension are better detected by the proposed method than with laser irradiation consisting of a single spot.

Open access