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Nitinol shape memory alloys present many applications in the industrial areas based on exceptional memory effect properties. The behavior of a shape memory alloy (superelastic effect) underwire form (four diameters: 1, 1.5, 2 and 2.5 mm and three lengths: 75, 150 and 375 mm) at drawing was analyzed using finite element analysis (FEA). The wire shape was C letter. The experimental temperature test, in a first step, was 23 °C (room temperature) and we analyze the appliance of four solicitation forces in order to determine the specific deformations and tensions. In second simulation step we apply a higher temperature, respectivelly 80 °C, in order to analyze the behavior of the element through transformation phase from martensite to austenite. The simulation provides information on the total deformation, equivalent stress, and equivalent elastic deformation of the intelligent elements under external solicitations pointing the appearance of maximum and minimum solicitation areas.

The present paper describes the challenges and preliminary results obtained during the design and implementation of a disassembly system for capacitors placed on printed circuits boards. This research is included in an attempt to reduce the impact of the electronic waste. The proposed architecture includes a six axis multipurpose industrial robot, dedicated sensors and a custom built tool. An originally designed rotary tool, with a specific type of drill bit, was used to dismantle each capacitor on the board. A sensor triggers the tool for the drill rotation when the perforation is accomplished accordingly, so that the friction force is big enough to initiate the dismantling procedure. Using the rotation movement of the drill, at a calculated number of rotations, the capacitors are successfully dismantled from the printed circuits board. An artificial vision system composed from a stereo camera and an image-processing algorithm, provides data with regard to the position of each capacitor on the printed circuit board. A vacuum cleaner was integrated in the scheme to recover the capacitors after dismantling. The scheme design was perpetually optimized using dedicated simulation software. Also, preliminary results obtained on the physical system underline the potential advantages of the proposed approach.

We describe in this paper an extension of standard Genetic Programming where the terminal set of the algorithm is expanded with a set of basic models generated offline using a deterministic approach. The new algorithm called EMM-GP (Genetic Programming based Evolvement of Models of Models) uses a specialized mutation operator to sample this set during the recombination phase in order to create models that reuse valuable building blocks. In this work, a preprocessing of model set by means of clustering is considered.

In this study we have enhanced the structural assessment analysis of a river-shipyard small size floating dock, with length overall of 60 m, for equivalent quasi-static oblique design wave conditions. The small size floating dock hull has two constructive layouts for the water ballast side tanks. The oblique design wave heading angle is in the range of 0 to 360 deg. The floating dock equilibrium in oblique equivalent design waves is achieved by own non-linear three parameters iterative program. The numerical analyses are done on full extended 3D-FEM structural models, from side to side and from stern to bow, of the small size floating dock, with specific boundary conditions for global and local strength computations. The modelling of the external oblique equivalent design wave pressure has requested to develop specialized user functions into FEM code. There are considered several loading scenarios of the small size floating dock, according to the shipbuilding classification societies. The structural assessment is based on three criteria: yielding stress, buckling and freeboard limit values. The numerical results of the structural assessment for the small size floating dock in oblique equivalent design waves made possible to establish the wave design height limits, according to the safety criteria restrictions.

The subject of this paper is to the study the microclimate inside a heritage building. The Gheorghe Asachi Auditorium is one of most important building in the university and in the history of Jassy. Build in 1897, it was inaugurated by King Carol I. The auditorium serves as meeting place and manifestations for different occasions. Auditorium is built in baroque style with multiple paintings, artworks and wooden elements sensitive to moisture and temperature variations. CFD analysis is the proper tool for understanding the phenomena’s regarding the movement of large volume of warm and moisture air. The analysis allowed us to make some recommendations to the conservation of such historical place but with regard to main human comfort.

Thermal comfort is a general term that describes the sensation of warm or cold for the occupant, defining the state of mind of humans that expresses satisfaction. Because 90% of our time is spend inside the buildings is essential to achieve a good thermal comfort. In this paper we present two different heating system that are used in more than 90% of the church in our country. The article test two different heating system in order to evaluate the thermal comfort of the occupants and if the climate meet the requirements for the churches where the paints and the artworks must be kept in good condition for future generation.

The mass electronics sector is one of the most important sources of waste, both in terms of volume and materials content with dangerous effects on the environment. Printed Circuit Boards (PCBs) are the most valuable component embedded into Electrical and Electronic Equipment (EEEs). The current amount of electronic systems is impressive while manual dismantling is a very common and non-efficient solution. On average, waste PCB accounts almost from 3% to 5% of the overall weight of waste electrical and electronic equipment. At this time, in Romania, the implemented solutions for waste PCB reduction are in a research phase, with no existing technological procedures that can be replicated. In the context of the TRADE-IT project we aim to design replicable architectures for waste printed boards reduction. Starting from the largest base plate and continuing to the smallest size, Extended ATX, ATX, Micro ATX, Mini ITX are some of the most used boards in a computer. When choosing a base plate from the ATX and/or microATX range, the shape factor must fit on a universal support bracket. The shape factor identifies the size of the circuit board, the location of the slots, and the location of the display board that comes out on the back of the computer. The shape factor also identifies the location of the holes that are used to mount the base plate in the universal clamp holder. Taking into account that capacitors represent approximately 8.6% of the PCB mass, we aim at designing an automated driven tool for their removal. The design is based on a robotic arm for motion manoeuvring, a programmable screwdriver and a custom-made end tool. In the current phase the proposed design was evaluated on controlled individual tests. The initial results highlight the feasibility of the proposed design while uncovering potential challenges for real-time implementation.

IRT – infrared thermography has met an extensive popularity among the non-destructive technologies. This paper is presenting some of the monumental church that had been examine with thermovision camera in order to assess the behavior of structure to ageing, earthquake damages, detect hidden characteristics or order anomalies. IRT investigation is based on principle that heat flowing in a material is altered by presence of all kind of anomalies, our job been to discover and interpreting. Thus heat bridges can be detected, heat loses and air leakage can be identify or the presence of mold, moisture is growing in a particular area.

This study is developed for the strength analysis of a large floating dock, with length over all of 209.2 m, obtained from a conversion of an off-shore barge. The docking operations are evaluated by global and local strength criteria. The first operation scenario includes an entire translation process of a ship from the quay to the floating dock railway system, in a river shipyard location, including the main intermediate steps. A second set of operation scenarios include several trial docking cases, at full capacity, considering also the initial state without docking ship that is specific for transit condition between ports. The structural numerical analysis is developed on a very large 3D-FEM model, one sided, full extended over the length, involving an own iterative algorithm for the dock and head design wave equilibrium parameters computation and user functions for the quasi-static head wave pressure application on the external dock shell. The large floating dock has operations in sheltered and unsheltered environments and can be relocated on river and costal waterways, under specific wave’s conditions, according to the shipbuilding classification societies design rules. The numerical results are making possible to evaluate the several operations of the large floating dock by strength criteria.

Surface roughness plays a very important role in micro milling process and in any machining process, because indicates the state of the machined surface. Many surface roughness parameters that can be used to analyse a surface, but the most common surface roughness parameter used is the average roughness (Ra). This paper presents the experimental results obtained at micro milling of the C45W steel and the ways to determine the Ra parameter with respect to the working conditions. The chemical characteristics of the material were determined from a spectral analysis, chemical composition was measured at one point and two points, graphical and tabular. A profilometer Surtronic 3+ was used to examine the surface roughness profiles; the effect of independent parameters can be investigated and can get a proper relationship between the Ra parameter and the process variables. The mathematical model were developed, using multiple regression method with four independent variables D, v, ap, fz; the analysis was done using statistical software SPSS. The ANOVA analysis of variance and the F- test was used to justify the accuracy of the mathematical model. The multiple regression method was used to determine the correlation between a criterion variable and the predictor variables. The prediction model can be used for micro milling process optimization.