Quasi-regular Tessellation of Hexagons

An algorithm for quasi-regular hexagon tessellation of uniformly distributed points is presented. At first, the needed definitions and notations are introduced. Then, the algorithm for the tessellation, based on "laying-down the sticks" analogy, is given. At the end, the estimation of the algorithm time complexity is done

A New Approach for Vertex Guarding of Planar Graphs

Vertex guarding is one of many optimisation problems in graph theory with wide area of applications. It is proven to be NP-hard, therefore fast approximative solutions are significant. In the paper, at first, known algorithms are considered, and then a new algorithm working on planar graphs is introduced. The new algorithm is based on the dynamic approach and produces better and faster solutions. Its efficiency among other algorithms is demonstrated experimentally. In addition, ideas to additionally improve the algorithm are presented at the end

Approximative Terrain Guarding with Given Number of Guards

Guarding a surface is a well known optimization problem of the visibility site analysis and has many applications. The basic problem is searching for the minimum number of guards needed to guard (see) the entire surface. More realistic is the guarding where the number of guards is upward limited and the optimization problem is to search for their locations in order to guard as much surface as possible. In the paper this problem is treated in detail. Several known heuristics (greedy add, greedy add with swap and stingy drop) are revised and a new technique called solution improving technique is proposed. The technique improves the results of the known algorithms and is used in indirect solving of the problem. Tests on 44 DEMs from USGS DEM Repository showed that our technique yields comparative results for smaller number of guards and better results for higher number of guards

Green strength sustainability: a case study of chemical engineering students

Green chemistry is a relatively new area of science and technology aimed at improving chemical processes and thereby avoiding negative impacts on human health, safety, and the environment (EHS). It is based on careful selection of raw materials for the production of various products, excluding the use of hazardous substances. The field of green chemistry has received much attention from the scientific and industrial communities in almost every highly industrialized nation. It is understandable that the principles of green chemistry should generate strong interest in countries or regions with high production capacities. Unfortunately, that industry resulted in a number of highly contaminated sites, hazardous and resource consuming production tools. A strong industrial development in European Union (EU) countries took place in last two decades focused on a profit, when there was small or no concern about some specific environmental issues. Human health and safety was rather controlled with robust standards. Environmental, health and safety protection remain a major component of co-operative activities between EU and other world. In particular, management of environmental risks associated with man-made changes, industrial, agricultural and military wastes, including risks for soil, water, air and the food chain and possible remediation are identified as one of the three priorities of the EU “Specific measures in support of international co-operation” program. These are challenges that need to be faced worldwide. With that respect, Green Chemistry is a promising approach to pollution prevention because it applies innovative scientific solutions to real world environmental situations. Green sustainability has started from educational and training institutions on entire vertical of education. In our research, we investigated chemical engineering freshman and senior students considering their perception toward importance of EHS area and about self-reported level of green competencies achievement during study. Freshman and senior students of chemical engineering estimated importance of green competencies as highly desirable. Existing curriculum in chemical engineering allows students achievements at basic level, while for high level of green chemistry; curriculum upgrade / modification is needed. It was judged that proposed green chemistry courses show potential for implementation and use at competitive higher education and training

Development of STRENGTH e-platfom

In this part of the project a technical framework (e-platform) was developed in terms of design, planning, arrangement and operation (including approbation of demo and final versions) as a mutual concept of project consortium. The planned activities included five steps, each exploiting appropriate methods and techniques as follows: Preparation / planning; Building up; Deploying - transfer of the site to live server(s); Maintenance - scheduling the technical support regarding time, content, updating and financial resources; Evaluation of operation - review of feedback comments / errors, bug fixing, upgrading