Scientific Bulletin Series C, Volume XIX (2005)

REDUCING THE ENVIRONMENTAL IMPACT OF MINING IN THE CONTEXT OF SUSTAINABLE DEVELOPMENT

Livia ADAM, Eng. Corneliu POPESCU, Eng. Mihail Nicolae RUDEANU, Economist,. Adriana BOCIAT, Eng

Abstract: The paper, a synthesis of a larger analysis performed in the past years, deals with the problems of identifying the factors affecting environment related to mining activity an d proposals to reducing the negative effects. In this respect, the main characteristics of the Romanian mining industry are analyzed, and the impact assessment on main environmental factors is evaluated. On this basis, the key measures to be performed, in the idea of sustainable development are presented.

Keywords: –

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INTELLIGENT END-EFFECTORS FOR ASSEMBLY ROBOTS

Ferenc ALPEK, Ferenc SZEKELY

Abstract: Manufacturing automation helps to increase the qu ality and reliability of products with reduced costs. The Intelligent Manufacturing Systems (IMSs) using robots can realise the advanced automated production. The most important and complicated operation of the robotized production is the assembly. During automated assembly a lot of end-effect ors (grippers, tools and special devices) have to be used to make the “final version” of the product. The end –effectors are built into the last robot wrist. During automation the human involvement has to be replaced with sensory systems and advanced control systems realising the monitoring and adaptive control of processes. Intelligent end-effectors (grippers, micro-grippers, tools and gripper and tool changers) are the very important components of the assembly robots.
To replace partly the human intelligence with machine intelligence using intelligent end-effectors is the goal of this development work.
The present paper gives a brief overview about recent developments in these fields, primarily focused on the gripper applications.

Keywords: Robot grippers, micro-grippers, sensory systems, intelligent peripheries, end-effector’s changers

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THE RATIONAL PARAMETERS OF THE TOP CAVING LONGWALL FACES IN THE CONDITIONS OF JIU VALLEY – ROMANIA COALFIELD

Iosif ANDRAS, Nicolae ILIAS, Sorin RADU, Ph.D., Mihael MELCZER

Abstract: The top caving mining method is a high productivity technology being more and more widely used worldwide. In order to implement this method in Jiu Valley coalfield, the rational parameters of faces were determined, such as: the mining height, the hanging block height, the shifting between two adjacent slices, as a function of the different categories of mining conditions (seam thickness and slope, mining depth, physical-mechanical properties of surrounding rocks and coal, the mining method etc.). The paper deals with these calculation using deterministic and FEM modeling.

Keywords: coal mining, top coal caving, mining methods

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MATHEMATICAL MODELING OF WASTE WATER CLEANING PROCESS IN SEDIMENTATION TANKS

Iosif Andras, Valeria Victoria Iovanov, Miodrag Iovanov, Angela Draghici

Abstract: A model of the concentrations of suspended solids (SS) in the aeration tanks and in the effluent from these during sedimentation operation is established. The model is based on simple SS mass balances, a model of the sludge settling and a simple model of how the SS concentration in the effluent from the aeration tanks depends on the actual concentrations in the tanks and the sludge blanket depth.
The model is formulated in continuous time by means of stochastic differential equations with discrete-time observations. The parameters of the model are estimated using a maximum likelihood method from data from an alternating wastewater treatment plant.
The model is an important tool for analyzing ATS operation and fo r selecting the appropriate control actions during ATS, as the model can be used to predict the SS amounts in the aeration tanks as well as in the effluent from the aeration tanks.

Keywords: Aeration Tank Settling, mass balance, grey-box models, statistical identification, on-line measurements

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SELF-REGULATING TWO D-O-F CONNECTED PLANETARY GEAR DRIVES HAVING CONSTANT TRANSMISSION RATIO

Dr. Ferenc, Levente Czégé

Abstract: The study below deals with the two degree-of-freedom connected drives having constant transmission ratio. These connected systems consist of two differential gear drives and two one degree-of-freedom gear drives. We define the necessary kinematic- and inner ratios, than we determine the possible powerflows of the connected system. The study shows expressively the evolution of the inner motion state which meets the moment- and power equlibrium conditions. In this state the connected planetary gear drive works with optimal efficiency.

Keywords: differential gear drive, connected drive, self regulation, two degree-of-freedom system

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A comparison of a tensile test with a planar simple shear test in sheet metals

Tadeusz Balawender

Abstract: The tensile test is commonly considered as the standard test in sheet metals, although the mechanism of plastic deformation during tension is very complicated. The planar simple shear test is more suitable to determining mechanical properties of these materials. In the article, the characteristics obtained in the tensile test are compared with the same obtained in the simple shear test. The investigations were performed on ETP-cooper, CuZn37 brass and low-carbon steel sheets.

Keywords: plasticity criteria, simple shear test, tensile test

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COMPUTER AIDED EQUITHERMICAL ADJUSTMENT IN THERMAL MANAGEMENT

Petr BARON, Peter BRÁZDA

Abstract: The paper describes the possibilities of communication adjustment system with superior layer, represented by software package created by PAUFEX Co. for adjusting of regulator using ekvithermical regulation by scanning temperature of water in central heating and outdoor temperature with servo-unit controlling converter vent.

Keywords: Ekvitermical regulation, outdoor temperature, Servo-unit controlling converter vent

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CONSIDERATIONS CONCERNING THE MANUFACTURING THE SPIROID HOB WITH REVERSE TAPERED

Vasile BOLOŞ, Codruţa BOLOŞ, Bogdan BUCUR

Abstract: The paper presents the manufacturing particularities of the milling worm used in the processing of the spiroid hob with reversed tapered. It is taken as an example the real case of the archimedical type worm milling tool used in the construction of spiroid wheels with axial module ma=2,5 mm, Z2=47 and axial distance A=56.

Keywords: Hob, Hobing, Spiroid

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AUGMENTED VIRTUAL REALITY APPLICATIONS IN MANUFACTURING

Peter Brázda, Jozef Novák-Marcinčin

Abstract: Augmented Reality (AR) is a growing area in vi rtual reality research. The world environment around us provides a wealth of information t hat is difficult to duplicate in a comput er. This is evidenced by the worlds used in virtual environments. Either these worlds are very simplistic such as the environments created for immersive entertainment and games, or th e system that can create a more realistic environment has a million dollar price tag such as flight simula tors. An augmented reality system generates a composite view for the user.
It is a combination of the real scene viewed by the user and a virtual scene generated by the computer that augments the scene with additional information.

Keywords: virtual reality, augmented reality, virtual technologies

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CAD ASPECTS OF THE DESIGN PROCESS OF A COUPLING WITH FRICTION SHOES AND ADJUSTABLE CENTRIFUGAL DRIVING

Adrian BUDALĂ, Aurel JULA

Abstract: The paper presents few stages of the design process of a coupling with friction shoes and adjustable centrifugal driving. There are also presented some advantages of the using of CAD software.

Keywords: Coupling, adjustable centrifugal driving, CAD

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