The 14th issue of RECENT journal was edited and multiplied with support of:
MATHEMATICAL MODELS FOR HSS TOOL RELIABILITY PARAMETRICAL ESTIMATION
» Abstract. Starting from the failure mechanism of HSS tools, in the paper are proposed two new theoretical models for the reliability model. These models can describe more accurate the tool reliability than the normal model and are easier to use. On the basis of these models, one can estimate the MTBF which leads to a smaller risk for the manufacturer facing the tool reliability certification.
» Keywords: reliability, estimation, cutting tools
MULTI-OBJECTIVE OPTIMIZATION IN SPUR GEAR DESIGN
» Abstract. The multi-criterion design problem of a pair of involutes spur gears is formulated and solved as a general nonlinear optimization problem. Its distinguished feature is the use of life balance criteria of gear teeth (bending fatigue and contact fatigue) by varying of the strength of their materials. The proposed approach has two stages: at the first stage, the parametric space is preliminary determined by the use of quasi-Monte Carlo method and a feasible set of possible solutions is pointed out. At the second stage, contracted subsets of Pareto optimal points are selected in order to make a final compromised decision. The proposed approach is illustrated by a numerical example.
» Keywords: multi-objective optimization, nonlinear optimization, spur gears
DESIGN OF A FAMILY OF PARTS USING ProE 2001
» Abstract. The paper presents a method for developing a number of screws based on a certain model. The screws will be automatically designed upon entering their dimensions into a table.
» Keywords: design, family of parts, ProE 2001
LOWEST DATA BASE FOR THE SYNTHESIS OF MANUFACTURING TASK IN FLEXIBLE MANUFACTURING SYSTEMS
» Abstract. The first stage in designing any of the flexible manufacturing system consists in the analysis of the manufacturing task. Flexible manufacturing systems (FMS) are adapted to the manufacturing charge. There is no “general” FMS, but only adapted FMS to the peculiarities of an item class or family – in this analyzed case, the flexible manufacturing system for round shafts processing. The data basis so constituted contains the elementary geometrical components of the manufacturing task, accordingly to the symbols of the mathematical model matrix. A data basis was conceived, containing the sizes and features of all the elements belonging to all fixed round shaft families. The computer software was realized in the Visual C++ programming language.
» Keywords: flexible manufacturing system, manufacturing task, simulation
Aurel FRATU, Mariana FRATU
DYNAMICS MODEL OF ROBOTS
» Abstract. Dynamic modeling of a robot manipulator consists of finding the mapping between the forces exerted on the structures and the joint positions, velocities and accelerations effectuated in joints of robot. Two formulations are mainly used to derive the dynamic model namely, the Lagrange formulation and Newton - Euler formulation, the former being simpler and more systematic.
» Keywords: robots, modeling, dynamics
Mariana FRATU, Aurel FRATU
APPLICATION’S DEVELOPMENT WITH SCADA SYSTEM
» Abstract. This paper describe the SCADA systems in terms of their architecture, their interface to the process hardware, the functionality and the application develop-ment facilities they provide. Some attention is also paid to the industrial standards to which they abide their planned evolution as well as the potential benefits of their use.
» Keywords: supervisory, monitoring, control system
DEVICE FOR SPATIAL ORIENTATION
» Abstract. The paper presents the kinematical and constructive principles of a device for spatial orientation through rotation around two axles, based on the principle of the planetary gearing and powered by electrical step-by-step engines, digitally controlled.
» Keywords: device, spatial orientation
NOISE IN TV CHANNEL. NOISE MEASURING AT TV RECEIVER ENTRANCE (4th PART)
» Abstract. This paper presents the experimentally results of noise indicators measuring in different receiving conditions at TV receiver entrance. The experimentally measurements were concentrated onto determining the parameters of the noise in UHF frequency band TV channels. The data acquisition system was used to measure various parameters of fluctuation noise at TV receiver entrance for identifying the character of the noise that predominantly affects image quality. Noise parameters are important in understanding the noise influence on the quality of received images and for selection radio channels which permissive optimum radio links.
» Keywords: channel noise, radio communications system noise, fluctuation noise measuring
Ioan PANTEA, Horia TÂRZIU
STUDY OF MOTION EQUATIONS IN A TECHNOLOGICAL PROCESS
» Abstract. In this paper the movement equations necessary to simulate a technological process are determined. The equations express the trajectory of the relieved motion of the points linked to the relieving device in relation to the xkykzk system considered immobile and they are used to determine the profile of the rectifying disk used for obtaining the profile of the given chipping edge. More so, the reciprocal problem is being put under discussion: knowing the disk’s profile, the equations of the trajectory of the relieved motion of the points linked to the relieving device in relation to the xkykzk system considered immobile are determined and are applied to solving the problem of the chipping edge’s profile in the calculus section.
» Keywords: coordinates, trajectory, profiled motion, mobile system
Maria POPESCU, Elena HELEREA, Dana LUPSA-TĂTARU, Alina NEAGOE
QUALITY ASSURANCE IN HIGHER EDUCATION: PROCESSES, STRUCTURES, ACTORS
» Abstract. The accent on the quality has become an important element of the strategies applied in the Romanian Higher Education in order to maintain in competition the universities in a very competitive and rapidly changing world. These strategies must assure the convergence of the university actions to the European exigencies on quality of the educational services, a central axis of the reform in the Higher Education area, usually named Bologna Process and also the Romanian documents concerning quality in education adopted by Education and Research Ministry (MEdC). The central idea developed both in the European and the Romanian documents concerning the quality of the educational services is the basic role of each university in achieving the quality and developing their own quality assurance system. The aims of this paper are: clarifying the concepts on quality assurance of the educational services; presenting the basic components of the quality systems in Higher Education Institutions; underlying the importance of the behavioural aspects and the attention that must be accorded in order to develop the quality culture as part of the programs for the implementation of the quality management systems in universities.
» Keywords: Total Quality, Quality Assurance System, Quality Culture
ENVIRONMENT PROTECTION IN A CUTTING TOOLS PRODUCTION SYSTEM
» Abstract. This article is about environment protection in a cutting tools production system. It treats problems about water, air and sol protection measures, sonorous and thermo pollution and finally classify wastes in metallic wastes (metal chips, ends and bar ends, pieces resulted from dissembles), nonmetallic wastes (paper wastes, plastic wastes, glass wastes, blown lubricant, gum elastic, bricks, abrasive blade, wood chips), asbestos, slime, residual water, grinding compound and garbage.
» Keywords: environment protection, waste