Analele Universitatii

9-16

Authors: Olga-Ioana Amariei, Codruta-Oana Hamat, Daniel-Mihai Amariei

In this paper we propose a protocol for economic decision-making by the management of an industrial enterprise, which wishes to set up a new production unit. The problem is finding the location of the new production unit, which will minimize the total transport cost, consisting of an amount of costs directly proportional to the distances between the new and existing locations. In order to obtain the optimum location, the QSB software package was used, which uses, besides the Manhattan model and the Euclidean and Euclidean quadratic distance measurement model.

25-30

Authors: Marcel Burduniuc, Ion Stratan, Tudor Ambros

In the paper is done the calculation of the magnetic field of the threephase power transformer with three columns in extreme conditions. The calculation is performed with FEMM application based on finite element theory. The distribution of the magnetic flux from the transformer's magnetic core was obtained. It has been demonstrated the possibility of specifying of the winding and the magnetic system parameters of the transformer.

45-48

Authors: Kristijan Cincar

Ambient Assisted Living (AAL) systems help people to stay active and have a decent life with the help of continuous monitoring for healthcare. Sensors help us to monitor, but the activity of sensors to false positive or negative decay of these monitoring and the status of worships.This work we analyzed detection and tolerance for event triggering sensors in AAL systems.

53-58

Authors: Lenuta Cîndea, Vasile Iancu

The paper includes a comparative study on the efficiency of dimensional stabilization of welded stitches in P265GH steel pipes by local-stress relief heat-treatment and low frequency mechanical vibration. Considering the fields of use, these steels must provide high temperature resistance (creep) and ductility, especially elongation and cracking, at high, stable values during the use of the metal structure. Taking a decision on applying stress relieving treatment to a welded structure should take account of certain major factors. Also, depending on the level and distribution of the residual stresses, the volume of the weld structure and its complexity, it will be decided whether the stress will be done totally or locally. Also, one of the drawbacks of applying the method is that stress relieves the manufacturing time and cost of the welded structure. If for a thermally stressed part the duration is 24 hours or more in the case of mechanical vibration stabilization, the time shortens significantly.

67-75

Authors: Anthony Ede, Oluwarotimi Olofinnade, Solomon Oyebisi, Akpabot Akpabot, John Oluwafemi, Kehinde Oyeyemi

Selection of construction materials are normally based on their ability to support design loads all through the service life of the structure to be built. For a reinforced concrete structure, the prime choices fall on the quality of concrete and steel reinforcing bars. Concrete is a composite of cement matrix which fills the space between aggregates and binds them together. Concrete quality fluctuates considerably for various reasons such as immense variability of constituent materials’ properties,the skill of the producer, placement procedure and environmental issues. Concrete is universally accepted for its excellent compressive strength. Concrete’s poor tensile strength is normally combined with the high tensile strength of steel reinforcing bar, providing a reinforced concrete composite that is universally accepted for construction. Steel is manufactured in specialized plants and the properties are controlled and certified by the manufacturer. The designer is, therefore, more confident in specifying steel quality complying with a relevant standard, while the choice of concrete mixes is not easy. Nevertheless, concrete and steel complement each other, compensating the weaknesses in the properties of the two materials, thereby making it a universal accepted construction material that has built the world’s most buildings and infrastructure. But due to the frequent cases of the collapse of reinforced concrete buildings and infrastructure in Nigeria, a study of the properties of steel samples available in Nigeria is essential. The scope of this research is on factors that influence the ductility of reinforced concrete, i.e., the properties of steel rebar. This study considers the yield strength and the chemical properties of the three most common diameters of steel rebar used in Nigeria. The results show some deviations in mechanical characteristics and chemical properties of some of the samples. This confirms that some of the samples fell short of the BS codes’ benchmarks for steel rebar.

86-92

Authors: Gilbert-Rainer Gillich, Vasile Iancu, Nicoleta Gillich, David Lupu, Andrea Amalia Minda

Estimating the harmonic components of a signal is based on calculating the signal energy on certain spectral bins that position is defined by the signal time length. Because of this mode of calculation, a difference between the true frequency and the estimate is usually found. In this paper, we present an advanced frequency estimation method, which searches first for the time length for which an entire number of cycles is contained in the signal and afterward calculates the Discrete Fourier Transform (DFT). The results have been found significantly closer to the true frequency as those obtained by a standard DFT applied to the original signal, but it still depends on the number of cycles involved. To further improve the estimation results we propose a methodology to make a correction depending on the number of cycles and sampling frequency.

99-106

Authors: Sava Ianici, Draghiţa Ianici

Research on the harmonic transmissions has shown that their functional performances are mainly influenced by the kinematic and dynamic behavior of the flexible wheels in these transmissions. The paper presents a study of the particular aspects of kinematics within a double harmonic transmission. This study aims to present the mathematical algorithm for determining and constructing the trajectories of points located on the average fibers in the two front surfaces of the flexible wheel from a double harmonic transmission. In order to realize the graphical constructions of the trajectories of these points of the flexible wheel, an original calculation program was developed and run, written in the language Visual Basic.

119-124

Authors: Tatian-Cristian Mălin, Gilbert-Rainer Gillich, Dorian Nedelcu

The retrieval and storage of information from historical earthquake records are very important for the study of seismic activity and the prevention of the danger that earthquakes represent in areas with intense seismic activity. This is possible due to modern techniques and methods of processing, converting old data into digital data and storing them on online databases. This paper presents some important web-based database that provides tools for searching, selecting and downloading ground motion data.

133-138

Authors: Calin-Octavian Miclosina, Zoltan-Iosif Korka, Vasile Cojocaru

The paper presents the manner of determination of forces that act on a workpiece grasped by a pneumatically driven robotic gripper. The starting point consists of experimental determination of the pushing force necessary to move the workpiece held between the gripper's fingers. Then, by using theoretical relations, the friction force between the workpiece and the fingers, and the prehension force (also called gripping force) are computed, for different values of the pneumatic driving system pressure.

147-152

Authors: Ion-Cornel Mituletu, Deian-Dorel Ardeljan, Andrei-Viorel Aniţulesei

The paper describes the way of a system dimensioning required to achieve a linear displacement measurement. The system is based on a microcontroller and an incremental encoder. Taking into account the needing of electronic parameter adaptation at the interfacing of the incremental encoder and the microcontroller, a constructive-functional optimization is accomplished. The sensibility of displacement measurement is given by the number of pulses per angular unit, the microcontroller processing and counting speed as well as the efficiency of implemented algorithm and source code. At the dimensioning of electronic circuit is also requested to consider the possibility of perturbation inducing due to the electromagnetic interference of own sources or from environment.

161-168

Authors: Siti Nur Aqilah Amanina Mohd Kassim, Md Azree Othuman Mydin

In recent years, there has been a growth in the population and migration of people from rural areas to urban settings. This phenomenon serves as a contributing factor to the increase number of flyovers. Even though the growth of urban flyovers has optimized the urban transport system and improved the spatial structure of the city, the utilization of space under overpasses has many problems, and they can be dark, short, hostile, and abandoned spaces which are full of girders and include ill-shaped areas in some parts. A huge number of idle and forgotten spaces under the flyovers have been bred. Presently, dark and neglected, that is, the kind of derelict space that lurks below most highways and elevated roadways. Since the number of flyovers has been increasing nowadays, the idea of utilizing spaces under flyovers has become a moot point. The increase number of flyovers also resulted in many leftover spaces available under flyover. These unplanned spaces, if utilized properly, offer an abundance of opportunities. Hence, this study focuses on exploring possible construction and adaptive use of “grey space” under flyover. The case study will be in three main cities which is Penang, Kuala Lumpur and Johor Bahru. This research will be conducted through a combination of site observations, interview and questionnaire surveys. The main objective of this research is to propose three suitable designs for adaptive use of “grey space” under flyover that comply with rules and regulations. As for the conclusion, the size and the location of flyover will determine what can be developed. Hence, without performing any large construction, we will be able to utilize the leftover space under flyover.

181-190

Authors: Dorian Nedelcu, Gilbert-Rainer Gillich, Istvan Biro, Zoltan-Iosif Korka, Attila Gerocs

The objective of the paper is to calculate the velocities and accelerations for some points of the punching cards mechanism and to compare the results calculated through grapho-analytical method with the SolidWorks Motion results.

197-204

Authors: Marius Romocea

Given that the competition between the industrial companies is increasingly tough, the problem of setting up by them of the spare parts manufacturing programs with own resources has become of a great importance. Determining an optimal manufacturing program means setting up a program to ensure, with the material and human resources of the unit, an optimization criterion such as maximum profit, minimal expenses, minimum costs, etc. Next, we present the case where the "profit" optimization criterion is chosen using linear programming.

213-220

Authors: Vasile Solcanu, Marian Gaiceanu

The multitude of disturbing signals from the military operations theatres and battle platforms can lead to the nonlinear operation of radiofrequency (RF) modules in radio receivers with unfavorable effects on the processing of the useful signal. The authors propose in this paper a new way to compensate the operating effects of RF amplifiers in the nonlinear area by introducing a feedback loop based on signal decomposition in reverse power series.

231-238

Authors: Mihaela Dorica Stroia, Cornel Hațiegan

In the present paper we present 3D models of three types of components, parts of power supply system found in automobiles. Components were designed and dimensioned according to the needs of their rational exploitation. The three parts under analysis are battery connectors used in petrol or diesel automobiles. Material used for designing is nickel. Case studies consider a comparison between components behavior in terms of von Misses stresses, displacements, elongation, damage, life cycle, load factor or safety factor, when subjected to constraints and different loads.

245-252

Authors: Mohamad Izzat Zulkanain, Md Azree Othuman Mydin

Sensory integration provides a foundation for more complex learning and behavior. For most of us, effective sensory integration occurs automatically. For many people with autism, the process demands effort and attention with no guarantee of accuracy. Autism Spectrum Disorder (ASD) is referred as a spectrum disorder because each individual has different symptoms, sensitivities and level of functioning. Each of the autistic children’s sensory sensitivities differs from one to another. Specialized design of learning spaces for ASD children may unlock their full potential. Hence this research attempted to design sensory- friendly spaces for children with ASD to stimulate learning environment. The objectives of this research are in 3 folds; (1) to scrutinize the existing body of knowledge to ascertain relevant criteria exist to design space for ASD; (2) to evaluate three centres for children with ASD in relation to the body of knowledge examined; (3) to propose an inclusive design of spaces for children with ASD. Three case studies are chosen for these studies that are Calvary Victory Centre (Johor), Penawar Special Learning Centre (Johor) and National Autism Society Malaysia (NASOM) One Stop Centre (Selangor). Then, six components are identified to be considered in the design of the spaces and four stimuli consideration are identified that is needed to be implemented. So, designing a space that provide conducive environment for these children to use any of their senses comfortably, it may lead to effectiveness in learning process.