A Novel Approach for Bolted T-Stub Connections

This paper reports an investigation into new connection types and their behaviors determined using full-scale experiments. T-shaped connections were created using the IPE standard profile. The aim of this study was to analyze the influence of T connections based on the IPE standard profile, height of beam to height of T-stub joint (H) of T-stub joints, and lengths (X) of T-stub joints on the behavior of steel connections, in order to provide the necessary data for improving Eurocode 3 and enable efficient use of residue IPE standard profiles and back to the consumption cycle. While the moment resistance values increased with an increase in H from H_min to H_max in model groups with X of 126 mm, and the energy dissipation increased with an increase in H from H_min to H_max and also with an increase in the lengths (X) of T-stub joints from 54 to 126 mm.     

Numerical implementation of drop and tilt method of five-axis tool positioning for tensor product surfaces

The Drop and Tilt tool position method for five-axis machining positions a toroidal tool to have two points of contact with a tensor product Bézier surface. The method results in high order simultaneous non-linear transcendental equations that are slow to solve. In this paper, an efficient numerical implementation of the Drop and Tilt Method of multi-point tool positioning on tensor product surfaces is presented. The method was implemented in C++, and is a direct method that does not convert the tensor product surface into an intermediate representation such as triangles or point clouds. The method is successfully demonstrated on a number of tensor product Bézier surfaces.     

Electron beam processed surface textures on titanium alloys for fluid-drag reduction

Ti-6Al-4V and Ti-4Al-1.5Mn alloys were employed for electron beam processing with the aim to produce surface textures efficient for fluid-drag reduction. The as-resulted surface textures were examined by using advanced optical microscopy for surface morphology analysis, optical microscopy and scanning electron microscopy for near-surface microstructure observation. The titanium model with electron beam processed surface textures was tested in wind tunnel to evaluate their fluid-drag reduction efficiency. It showed that the as-resulted non-smooth surface was characterized by parallel ridges and grooves, with height and spacing able to be customized by adjusting processing parametres. The ridges displayed continuous scales while the valley of grooves presented V-shaped ripples. Their dimensions were also related to and could be controlled by processing parametres. Further, the near-surface region was occupied by fusion zone, heat-affected zone and base metal from the outermost surface to the underlying bulk alloy. The microstructure of fusion zone was characterized by martensite phase. A heat-affected zone was sandwiched between fusion zone and the underlying base metal, with different microstructural features compared to both fusion zone and the base metal. With respect to fluid-drag reduction efficiency, titanium model with electron beam processed surface textures exhibits a reducing efficiency over 15% at attack angles of 0° and ±1°, with an air flow velocity at 24 m/s.     

The role of psychology and social influences in energy efficiency adoption

Current energy efficiency policy and incentive programs tend to target economic motivations, which may misalign with other potentially important motivations arising from situational factors, individual differences, and social context. Thus, in this research, we review areas of work that have focused on psychological and social influences to energy efficiency adoption in commercial buildings. We then conduct an empirical scoping study interviewing 10 commercial building owners/managers (decision makers) and 10 experts/consultants (decision influencers) regarding perceived motives and barriers to energy efficient investments, decision-maker attributes, and the social context of the decision. Potential factors that emerge from the interviews, which are not yet extensively discussed in the energy efficiency literature, include owners/managers’ resistance to change and the influence of investment funding origins on the decision. Our results also suggest potential heterogeneity in energy efficiency decision-making philosophies between the two groups. Interviewed owners/managers prioritize corporate social responsibility (CSR) and prefer internal consulting (e.g., building engineers). Conversely, experts/consultants do not emphasize CSR and are more concerned with external policies. These findings suggest that accounting for the decision maker and the social context in which decisions are made could enhance the design of commercial sector energy efficiency programs.     

Climate dependence of energy saving strategies in public buildings characterized by change of use: an original case study

In the perspective of reducing land occupation of built environments, the most efficient strategy is to increase the reuse of obsolete or abandoned constructions instead of designing new buildings. This is particularly true regarding public buildings, usually characterized by considerable dimensions. The paper is focused on this issue, particularly on its energy implications. It analyzes the headquarters of the “G. D’Annunzio” University in Pescara, Italy, initially designed for commercial use and later converted to a university building during its construction. The authors first carried out a numerical analysis of the building energy performance in its current state and then they proposed some improvement interventions evaluating their incidence on the annual energy balance of the building, showing how the most commonly used energy saving strategies do not give the best results in any case, being greatly influenced by the climatic zone in which the building is located. Starting from these considerations, the authors carried out the analysis by considering three different Italian climatic conditions so as to determine their influence on the building energy performance and to define the best strategy for energy requalification in each climatic zone.     

Evaluation on Dorsey Method in Surface Tension Measurement of Solder Liquids Containing Surfactants

With the purpose of developing a feasible approach for measuring the surface tension of solders containing surfactants, the surface tension of Sn–3Ag–0.5Cu–xP solder alloys, with various drop sizes as well as different phosphorus (P) content, was evaluated using the Dorsey method based on the sessile drop test. The results show that the accuracy of the surface tension calculations depends on both of sessile drop size and the liquid metal composition. With a proper drop size, in the range of 4.5 mm to 5.3 mm in equivalent spherical diameters, the deviation of the surface tension calculation can be limited to 1.43 mN·m^?1 and 6.30 mN·m^?1 for SnAgCu and SnAgCu–P, respectively. The surface tension of SnAgCu–xP solder alloys decreases quickly to a minimum value when the P content reaches 0.5 wt% and subsequently increases slowly with the P content further increasing. The formation of a P-enriched surface layer and Sn₄P₃ intermetallic phases is regarded to be responsible for the decreasing and subsequent increasing of surface tension, respectively.     

Controlled Creating of Cracks in Concrete for Non-destructive Testing

The non-destructive assessment of cracks in concrete is a common task for which non-destructive evaluation solutions have been published. Primarily, these tests have been carried out on artificial cracks that have been created by using notches instead of natural cracks. This study evaluates a procedure designed to create reproducible and controlled cracks in concrete. The procedure is based on using expanding mortar in a series of blind holes. This is done in combination with carefully aligned reinforcement to guide the direction of the crack development. The depth of the crack is also controlled by reinforcement. Crack depth varies statistically in the range of the maximum aggregate size (16 mm) used for concrete.     

A model of energy management analysis,case study of a sugar factory in Turkey

This study presents a case study of energy management in a sugar factory in Turkey. The main idea of the study is to analyse energy consumption, the quantity of material production, and figure out a suitable energy efficiency for the case study of a sugar factory subsequently. Firstly, a material production and energy consumption audit were performed for the sugar factory. Secondly, energy efficiency was calculated from the energy data. The SPSS (Statistical Package for the Social Sciences) statistical software was used to ensure the accuracy of the data. The factory’s energy consumption was calculated as 43,590.25 toe (tons of oil equivalent) over the last year. These results were used for CUSUM (Cumulative Sum Deviation Method) graphics. This research poses the consumption of energy, cost of energy and the relationship between energy usage and material production of sugar. The unit of energy cost was 688.22 [$/toe] for the last year. This result showed that the factory decreased the unit of energy by optimisation. The results indicated that the investigated sugar factory should pay attention to the energy management issue in order to comply with the Energy Efficiency of Turkish Law and Directives.     

Thermal,electrical, mechanical and fluidity properties of polyester-reinforced concrete composites

Polyester particles in concrete are preferred because they provide thermal, chemical and water resistance. In this study, thermal conductivity, electrical resistivity, mechanical strength and water resistance properties of concretes containing polyester granules such as flame-retardant polyester, cationic dyeable polyester and polyester with a low melting point-filled concrete have been analyzed using a full factorial design via Minitab^® version 17. The effect of the most influential factors on thermal conductivity of polyester aggregate reinforced concrete composite has been determined as an interaction between the cationic dyeable and low-melt–point polyester. This mixture is suitable for production of thermal insulating concrete. Moreover, it is concluded that cationic dyeable polyester is the highest corrosion- and water-resistant product among the polyesters used in this study. The recovery rate of 33.94% in the thermal conductivity and 214.89% in the electrical resistivity of polyester-reinforced concrete composites has been obtained with a 28-day compressive strength loss of 41.94% according to the reference concrete in the full factorial design application. These results indicate that the polyester-reinforced concrete composites are quite effective in achieving thermal and corrosion resistance concrete but with noticeable compressive strength loss.