Dusko Letic

THE DISTRIBUTION OF TIME FOR CLARK'S FLOW AND RISK ASSESSMENT FOR THE ACTIVITIES OF PERT NETWORK STRUCTURE

This paper presents the ways of quantification of flow time qualifications that can be used for planning or other stochastic processes by employing Clarks methods, central limit theorem and Monte Carlo simulation. The results of theoretical researches on superponed flow time quantification for complex activities and events flow in PERT network for project management are also presented. By extending Clarks research we have made a generalization of flow models for parallel and ordinal activities and events and specifically for their critical and subcritical paths. This can prevent planning errors and decrease the project realization risk. The software solution is based on Clarks equations and Monte Carlo simulation. The numerical experiment is conducted using Mathcad Professional.

The Hyperspherical Functions of a Derivative

We present the results of theoretical research of the generalized hypersherical functionHS� by generalizing two known functions related to the sphere hypersurface and hypervolume and the recurrent relation between them. By introducing two-dimensional degrees of freedom k and nand the third, radius r� , we develop the derivative functions for all three arguments and the possibilities of their use. The symbolical evolution, numerical experiment, and graphical presentation of functions are realized using the Mathcad Professional and Mathematica softwares.

Orthogonal and diagonal dimension fluxes of hyperspherical function

In this paper, we present the theoretical research results of certain characteristics of the generalized hyperspherical function with two degrees of freedom as independent dimensions. Here, we primarily give the answers to the quantification of dimensional potentials (fluxes) of this function in the domain of natural numbers. In addition, we also give the solutions to continual fluxes of separate contour hyperspherical (HS) functions. The symbolical evaluation and numerical verification of the values of series and integrals are realized using MathCAD Professional and Mathematica.MSC 2010: 51M04; 33E99.

Researching Effects of Information Technologies Usage in Engineering Graphics Teaching

Universities and their faculties and colleges have a very complex function in society today, so it is necessary for them to establish the right balance when executing their tasks. On the other hand, economy has a need and obligation to invest in university educated personnel able to apply and develop new technological achievements. The paper presents new trends in technology and higher education of technical engineers which could be of great importance in future development of distance learning (e-learning). It also underlines the attempt of using the innovative models of work, which are presented and experimentally confirmed, to show a gradual transmission from traditional to a new view to engineering graphics teaching. Statistical analysis of the obtained results has confirmed that a distance learning model in engineering graphics teaching has a statistically relevant effect on teaching efficiency.

Some certain properties of the generalized hypercubical functions

AbstractIn this article, the results of theoretical research of the generalized hypercube function by generalizing two known functions referring to the cube hypervolume and hypersurface and the recurrent relation between them have been presented. By introducing two degrees of freedom k and n (and the third half-edge r), we are able to develop the derivative functions for all three arguments and discuss the possibilities of their use. The symbolic evaluation, numerical experiment, and graphic presentation of the functions are realized using Mathcad Professional and Mathematica. MSC 2010: 33E30; 33E50; 33E99; 52B11.

The Dimensional Fluxes of the Hypercylindrical Function

We present the results of the theoretical researches of some characteristics of the generalized hyperspherical function with two degrees as independent dimensions. Primarily are given the answers on the quantification of the dimensional potentials (fluxes) of this function in the domain of the integer natural numbers. Beside them, we have got the solutions for some continual fluxes of the contour hypercylindrical (HY) functions on the basis. The symbolical evaluation and numerical verification of the series values and integrals are realized through the program packages Mathcad Professional and Mathematica.

Software implementation of project duration assessment model and its evaluation

Determination of project completion time is crucial for considerable number of projects, especially for the time-terminated ones. Experience showed that it is not enough to use standard network planning methods (CPM/PERT) only, particularly for stochastic projects like research and development ones. In this paper, the project time determination is based on superposition for defined network diagram. Thereby, the basic network model that consists of two parallel flows is observed: critical and (sub)critical, and can be used for representation of any project plan. Then, the project time determination is calculated by analytical method — based on Clarks formulas. Project duration assessment model, that is developed, originates on analysis of analytical method, and its parameters are defined based on collected empirical material which includes sample of 43 completed project plans. It is implemented in interface of one of the project management software, and evaluation is achieved according to preset criteria.

Using automated reasoning system for data model correctness analysis

Data modeling is one of the most important activities in the process of information systems development which is based on domain knowledge in specific area. This paper presents a system for analyzing data model correctness from both syntax and semantic aspect. The system is based on using ontology for domain knowledge representation, transformation of data models and ontology to predicate logic form and their integration with data model quality rules. All components of the system are integrated by using XML form of their results. They create an input for an automated reasoning system, that provide answers regarding data model correctness.

The Relational Translators of the Hyperspherical Functional Matrix

We present the results of theoretical researches of the developed hyperspherical function for the appropriate functional matrix, generalized on the basis of two degrees of freedom, and , and the radius . The precise analysis of the hyperspherical matrix for the field of natural numbers, more specifically the degrees of freedom, leads to forming special translators that connect functions of some hyperspherical and spherical entities, such as point, diameter, circle, cycle, sphere, and solid sphere