Vulnerability to natural disasters in Serbia: spatial and temporal comparison

The frequency of natural disasters and the extent of their consequences at a global level are constantly increasing. This trend is partially caused by increased population vulnerability, which implies the degree of population vulnerability due to high magnitude natural processes. This paper presents an analysis of vulnerability to natural disaster in Serbia in the second half of the twentieth and the early twenty-first century. Vulnerability changes were traced on the basis of demographic–economic indicators derived from statistical data for local government units (municipalities) provided by the Statistical Office of the Republic of Serbia. Calculations were performed in the geographical information system environment. The results of the study show that spatial and temporal vulnerability variations are causally correlated with changes in the selected components. Significant rise of vulnerability is related to urban areas, while lower values are characteristic for other areas of Serbia; this is primarily a consequence of different population density

Development of reprogenetics and its demographic aspects

The development of reprogenetics during the last two decades of the XX century has brought a new age of reproduction. The paper surveys different types of reprogenetics in a wider sense, i.e. different assisted reproductive technologies (ART) that include manipulation of female reproductive cell out of a woman's womb. Development of reprogenetics is documented by available quantitative indicators of the number and success of ART procedures in developed countries at the beginning of the XXI century. Since 1978, when the first baby was born from in vitro fertilization, the number of children born that way has reached 1% of all children, and in some countries even over 3%. Moreover, existing documentation is incomplete and does not include all forms of assisted reproduction - in reality, the importance of assisted reproduction is even higher and becomes demographically significant. Hence the paper indicates existing and potential effects of the ART development on the demographic development i.e. on specific demographic aspects of this phenomenon. It also points out the effects on the level of fertility, on the changes of direct fertility determinants, and on the levels of mortality and infant mortality, as well as a new understanding of birth control, the possibility of affecting biological structures, and the changes of the fundaments of marriage and family. Development perspectives of reprogenetics are also being raised in the context of bioethical discussions and indicate ethical dilemmas related to assisted reproduction. Solutions to the dilemmas define the scope of applying new reproductive technologies in the future

Application of response surface methodology and fuzzy logic based system for determining metal cutting temperature

The heat produced in metal cutting process has negative influence on the cutting tool and the machined part in many aspects. This paper deals with measurement of cutting temperature during single-point dry machining of the AISI 4140 steel, using an infrared camera. Various combinations of cutting parameters, i.e. cutting speed, feed rate and depth of cut lead to different values of the measured cutting temperature. Analysis of the measured data should explain the trends in temperature changes depending on changes in the cutting regimes. Furthermore, the temperature data is modelled using response surface methodology and fuzzy logic. The models obtained should determine the influence of cutting regimes on cutting temperature. The main objective is the reduction of cutting temperature, i.e. enabling metal cutting process in optimum conditions