Volume 21, No. 3 (2015)
Articles
KINEMATICS OF THE V MECHANISM USED FORELECTRIC SWITCHERS BASED ON SPECIALISED SOFTWARE
PĂUN ANTONESCU(1), LIVIU-MARIAN UNGUREANU(2), COSTANTIN BREZEANU(3)
This paper is representing a continuing research of the doctoral thesis "Geometrical analysis and synthesis of mechanisms in the electrotechnical field". Using two Mathcad programs as mathematics analysis software and Solidworks as graphical analysis software it is dimensioned the new kinematics scheme of the high voltage V mechanism. Kinematic analysis is based on the mathematical model presented in the doctoral thesis mentioned above and graphical modeling and analysis is conducted to compare and complete the research regarding the V mechanism triadic chain 5R + T type.
NUMERICAL SIMULATION OF THE MOVEMENT OF SMOOTH PARTICLES AT THE ELECTROMAGNETIC SEPARATORS WITH DRUM
TUDOR CĂSĂNDROIU(1), GABRIELA VALERIA CIOBANU(1 2), LIANA ALEXANDRA VIŞAN(2)
The paper presents the main theoretical elements underlying the seeds separation process after their surface. During the seed cleaning and sorting process according to the surface condition machines with electromagnetic or magnetic separators drums are used. In this paper is made a comparative theoretical analyze of smooth seeds movement on electromagnetic drum surface and trajectory in free flight, neglecting and taking into consideration air resistance, detached from the separation drum and it is evaluated the collection area of detached seeds. On this basis, were carried out several case studies and numerical simulations for three different machines.
PREVENTION MEASURES OF ENVIRONMENTAL RISKS GENERATED BY UNCONTROLLED STORAGE OF WASTES – A REVIEW
MIRELA DINCĂ(1), GIGEL PARASCHIV(1), GHEORGHE VOICU(1), GEORGIANA MOICEANU(1), NICOLETA UNGUREANU(1), MIHAI CHIȚOIU(1)
The issue regarding the negative impact on the human health and environment, as a result of waste storage by using improper methods remains of great actuality, especially with the increasing trend of the generated wastes quantity. The present paper aims to present the most efficient methods that can be used to reduce and prevent environmental risks caused by uncontrolled storage of agricultural waste. Will be treated theoretical aspects related to the actual state of waste management in the E.U. but also in Romania, methods of treating organic waste, as well as prevention measures of environmental risks.
ENHANCING THE EFFICIENCY OF INDOOR LOCAL VENTILATION USING CROSS-FLOW FANS: CASE STUDY FOR A SMOKING CABIN
ANDREI DRAGOMIRESCU(1), ADRIAN CIOCĂNEA(1)
The paper presents an original solution for increasing air quality and reducing energy consumption of the local indoor ventilation by using cross-flow fans. The solution is a combination between the local exhaust ventilation (LEV) technique from industry, negative-pressure isolation rooms used in hospitals, and air curtains (AC) used for isolating of indoor/outdoor spaces. The solution provides a high air flow rate at low velocity due to the high value of the flow coefficient of the cross flow fans and, in the same time, allows modular setup according to local space geometry. A case study is proposed regarding the isolation of a smoking area where smell and airborne particles appear. A 3D numerical simulation was performed, in which one cross-flow fan with long axial length was considered. The optimum air flow rate and flow pattern was obtained in order to isolate the local space. The results show that a new approach for reducing sick building syndrome could be addressed by providing modular and local ventilation using cross-flow fans.
GIS BASED DECISION SUPPORT SYSTEM FOR SEISMIC RISK IN BUCHAREST. CASE STUDY – THE HISTORICAL CENTRE
DIANA GHEORGHE(1), IULIANA ARMAS(1)
Because of the increasing volume of information, problem decisions tend to be more difficult to deal with. Achieving an objective and making a suitable decision may become a real challenge. In order to better deal with decision making, decision support systems (DSS) have been developed. The decision support systems (DSS) can be used in any kind of a decision-making process and are very suitable in situations that involve a lot of stakeholders and a large number of criteria. DSS offers support in the decision-making process (how a decision should be made), and it does not focus on the result (what decision that should be made). DSS can also involve a large number of stakeholders and criteria, in the same time. A limitation of this method is that, regardless of the mathematical results, the final decision has to be made by the decision maker. Depending on the nature of the decision problem, a decision maker can use decision support systems (DSS), if the decision problem is economic or technical, and spatial decision support systems (SDSS), if the decision maker is faced with a spatial decision problem. The main objective of the present study is to apply a spatial decision support system in order to find a suitable shelter in the historical centre of Bucharest City in the post-disaster phase, in case of an earthquake occurrence. The present work represents a first step in applying SDSS in the context of the seismic risk in Bucharest. For the present paper, the SMCE Module for ILWIS 3.4 was used. The method included the following steps: structuring the problem in a decision tree, applying standardization and weighting methods to the criteria, finding suitable alternatives and choosing one of the alternatives. The results show that several buildings can be used as a shelter and among these are ‘Creditul Roman’ Bank Palace, the National History Museum and the National Bank of Romania.
ISSUES ON THE APPLICATION OF A QUALITY-RISK MANAGEMENT SYSTEM IN A HEALTHCARE SERVICES PROVIDER UNIT
CONSTANTIN MILITARU(1), LEONARDO VOINESCU(2)
A medical service, as a public service, is composed of a provider represented by the medical staff and a framework that carries out their work. Therefore, a qualitative management of services must be taken into account, on the one hand by the quality of care itself, and on the other hand by how the resource material is managed throughout the services provided. Fortunately, quality and risk management systems concepts are becoming more widely used in their speech, by the responsible with those services at European and national level. A quality medical service can be attained through a rigorous and effective management of the quality of medical care itself, and through increased quality of human resources and materials involved and ensuring health and reduce the risks of treatment/ care patients. The authors present in brief a model of risk assessments and risk classification in a medical unit.
INFLUENCE OF SCREENING BLOCK SUPPORTING WAY ON THE BEHAVIOUR OF A SOLID PARTICLE ON AN OSCILLATING SURFACE
EMILIAN MOŞNEGUŢU(1), VALENTIN NEDEFF(1), NARCIS BÂRSAN(1), ALEXANDRA-DANA CHIŢIMUŞ(1), DRAGOŞ RUSU(1)
This article shows a study aiming to identify the influence carried out by the supporting way of the working surface in the case of plane oscillating screening device, over the behavior of a solid particle. In order to achieve this, a theoretical study has been conducted by using a simulation program, Working Model 2D, within which two ways of supporting the screening block have been conceived: the working surface supported by tie-rods, and the surface suspended on tie-rods. Following the simulation, a series of physical parameters has been determined: the trajectory followed by the solid particle; the circuit of the solid particle during its movement on the working surface; the acceleration of the solid particle and the reaction force occurred between the solid particle and the working surface. Following the analysis of resulting values it may be noted that the best way to support the working surface, as far as the efficiency of mechanical separation is concerned, according to width and thickness of the solid particle, is obtained in the case where the working surface is supported by tie-rods, since the running time of the working surface is the highest and it is 4.12 seconds, value generating the high average moving speed; the particle’s rotation angle is from -2 rad to +4.8 rad, having as a result the amplest possible rotation.
NOISE PREDICTION, CALCULATION AND MAPPING USING SPECIALIZED SOFTWARE
ALINA PETROVICI(1), CLAUDIA TOMOZEI(1), RICARDO GEY FLORES(2), FLORIN NEDEFF(1), OANA IRIMIA(1)
This paper presents a set of software for prediction, calculation and noise mapping. These are useful both in assessing noise and adopting practical measures in order to reduce noise in areas with intense traffic. The software, through their working tools, allows making comparisons concerning noise before and after implementing noise reduction measures. The analyzed software's of noise prediction, calculation and mapping are specialized for noise generated by traffic.
THEORETICAL ASPECTS ON THE MOVEMENT OF PLANT FRAGMENTS ON THE SURFACE OF A PLANE SIFTERS CLASSIFIER
AUGUSTINA PRUTEANU(1), VALENTIN VLADUT(1), LADISLAU DAVID(2)
This paper presents the main theoretical elements underlying the process of dimensional separation of the fragments of chopped medicinal plants. To sort chopped plant mixture from the same medicinal plant, there are used vibratory classifiers with plane sifters, which are the active working body. Case studies were conducted and there were analyzed, based on numerical applications, the movements of plant fragments on a classifier with linear vibrations along the sifter, existing in practice. Numerical simulation has provided information on trajectory parameters of the jump of a plant fragment on the vibratory plane sifter, useful elements in the theoretical grounding of the equipment workflow.
EXPERIMENTAL RESEARCHES ON THE VEGETAL MATERIAL QUALITY, IN ORDER TO OPTIMIZE OF SOME PROCESSING PROCESSES OF THE MEDICINAL PLANTS
AUGUSTINA PRUTEANU(1), LADISLAU DAVID(2), VALENTIN VLADUT(1), ADRIANA MUSCALU(1)
In the production of medicinal plants, the phytotherapeutic products quality is given by the content and the amount of bioactive substances from the plant. The quality of the phytotherapeutic products is dependent on the quality of the vegetal raw material as well as by the quality of the manufacturing processes. This paper presents the experimental determinations of some physical and dimensional properties of the vegetal material, in order to separate by sorts and of obtaining of some vegetal extracts therefrom. The determinations were performed in order to optimize the separation and extraction processes of medicinal plants. Knowing the characteristics of the vegetal material is particularly important for the achievement of some high-performance technical equipment for processing of medicinal plants.
OPTIMIZATION OF DIMENSION AND SHAPE FOR BALL VALVE BODY IN FIRE SAFE DESIGN
GHEORGHIŢA TOMESCU(1), RADU IATAN(2), IULIANA IAŞINICU (STAMATE)(3)
The fire safe valves are designed for petroleum and petrochemical complexes and allied industries because working fluid characteristics result in a high fire risk, detonation and / or explosion. Fire Safe Certification is achieved through a standardized fire testing. This article aims to show how to optimize the shape and size of the main body of a ball valve in sequence CAD – FEM - testing and evaluation of the performance of valves when exposed to fire. This analysis is necessary because fire testing is expensive to verify and the validation of constructive solutions helps reduce production costs and achieve fire prevention through design.