Prepoznavanje phishing napada u poslovnim organizacijama

Phishing is a form of social engineering and cybercrime which entails theft of confidential information (personal or official) for financial gain. That is one of the oldest cyber threats. There is a wide range of phishing attack techniques, and the most frequent one is performed via electronic mail. Due to major changes in conducting business in the last pandemic, which entail remote work, fast digital transformation and the increase of ICT technologies, the statistics show that phishing attacks are on the rise. Employees who lack developed awareness of phishing attacks, responsibility and knowledge represent a potential danger to the entire organisation. This paper describes the research on e-mail phishing recognition in business organisations in Primorje-Gorski kotar County. The research showed that employees are not aware of phishing attacks to a sufficient extent and that all the habits contributing to the IT security level regarding these attacks are not satisfying. To protect against such attacks, organisations should, in addition to implementing safety technical measures, actively educate employees and periodically implement testing.Phishing je oblik socijalnog inženjeringa i računalnog kriminaliteta koji podrazumijeva krađu povjerljivih podataka (osobnih ili službenih) radi financijske dobiti. To je jedna od najstarijih kibernetičkih prijetnji. Postoji širok raspon tehnika phishing napada, a najčešći se izvodi putem elektroničke pošte. Zbog znatnih promjena u vođenju poslovanja posljednjih pandemijskih godina, koje podrazumijevaju rad na daljinu, brzu digitalnu transformaciju i povećanje korištenja ICT tehnologija, statistika pokazuje kako su phishing napadi u porastu. Zaposlenici koji nemaju razvijenu svijest o phishing napadima predstavljaju potencijalnu opasnost za cijelu organizaciju. Ovaj rad opisuje istraživanje o prepoznavanju e-mail phishing napada u poslovnim organizacijama u primorsko-goranskoj županiji. Istraživanje je pokazalo kako zaposlenici nisu dovoljno svjesni phishing napada te da njihove poslovne navike koje pridonose razini IT sigurnosti u odnosu na ove napade nisu zadovoljavajuće. Osim implementacije sigurnosnih tehničkih mjera, organizacije bi za zaštitu od phishing napada trebale aktivno educirati zaposlenike i periodično provoditi testiranje prepoznavanja takve vrste napada

ANALYSIS OF CORROSION DEPTH PERCENTAGE ON THE INNER BOTTOM PLATES OF AGING BULK CARRIERS WITH AN AIM TO OPTIMIZE CORROSION MARGIN

To ensure the better structural integrity and maximum safety of bulk carriers in the ship design phase, an appropriate corrosion margin is introduced by the classification societies, which should enable the exploitation of ships during the projected 25-year life cycle. The new Common Structural Rules introduce even higher corrosion margin value to ensure the structural integrity of the ship. This directly affects the increase in hull weight and thus the need for more total installed power and higher fuel consumption. Higher fuel consumption results in increased emissions which directly affects environmental pollution. For these reasons, efforts are being made to introduce alternative energy sources, cleaner fuel, ship weight reduction, and the overall economic efficiency of ships. Therefore, using experimental data collected on aging bulk carriers, the paper explores the corrosion margin reduction potential considering its impact on hull weight. Assuming that the corrosive processes occur after four years of operation, a linear model that describes the percentage of plate wear as a function of the as build-in the thickness of inner bottom plates (IBP) of fuel oil tanks (FOT) located on the double bottom of aging bulk carriers, is analyzed. Over the course of 25 years, the IBP segment was monitored on 36 different ships surveys. In this way, 520 input data describing the depth of corrosion were formed. At the same time, records were kept on the mean thickness of the original metal plate, which enabled systematization of the empirical database and grouping of measured values by intervals of original plate thicknesses, and simple conversion of corrosion depth into adequate percentage values. Depth corrosion percentages were represented by standard linear models known in the literature. Based on this analysis, representative numerical and graphical results were obtained. Conclusions from the paper can assist to optimize corrosion margin and the energy efficiency of future vessels

Analysis of corrosion depth percentage on the inner bottom plates of aging bulk carriers with an aim to optimize corrosion margin

To ensure the better structural integrity and maximum safety of bulk carriers in the ship design phase, an appropriate corrosion margin is introduced by the classification societies, which should enable the exploitation of ships during the projected 25-year life cycle. The new Common Structural Rules introduce even higher corrosion margin value to ensure the structural integrity of the ship. This directly affects the increase in hull weight and thus the need for more total installed power and higher fuel consumption. Higher fuel consumption results in increased emissions which directly affects environmental pollution. For these reasons, efforts are being made to introduce alternative energy sources, cleaner fuel, ship weight reduction, and the overall economic efficiency of ships. Therefore, using experimental data collected on aging bulk carriers, the paper explores the corrosion margin reduction potential considering its impact on hull weight. Assuming that the corrosive processes occur after four years of operation, a linear model that describes the percentage of plate wear as a function of the as build-in the thickness of inner bottom plates (IBP) of fuel oil tanks (FOT) located on the double bottom of aging bulk carriers, is analyzed. Over the course of 25 years, the IBP segment was monitored on 36 different ships surveys. In this way, 520 input data describing the depth of corrosion were formed. At the same time, records were kept on the mean thickness of the original metal plate, which enabled systematization of the empirical database and grouping of measured values by intervals of original plate thicknesses, and simple conversion of corrosion depth into adequate percentage values. Depth corrosion percentages were represented by standard linear models known in the literature. Based on this analysis, representative numerical and graphical results were obtained. Conclusions from the paper can assist to optimize corrosion margin and the energy efficiency of future vessels

Influence of silver addition on textural properties of new synthetic activated carbon

Starting from macroreticular styrene/divinylbenzene sulfonic acid ion exchange resin the two samples of synthetic activated carbons (SAC), with and without silver, were obtained through carbonization in controlled regime. Detailed sample preparation procedure is described. Characterizations of synthesized samples were conducted using XRD, SEM and N2 physisorption at –196 °C measurements. The influence of applied silver on textural properties of CAS was discussed.Physical chemistry 2006 : 8th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 26-29 September 200

Floristic composition as an indicator of destabilisation of lowland forest ecosystems in Posavina

Background and Purpose: The succession of forests in the Posavina region follows a pattern from forests of black alder and ash through stands of pedunculate oak to pedunculate oak-hornbeam forests. In the past hundred years, this lowland area has been affected by a number of factors, among which anthropogenic influences hold a primary position. This has resulted in a considerable deviation from normal, natural succession. The purpose of this paper is to analyse the present condition, the degree of destabilisation and the future developmental trends of pedunculate oak stands by drawing on previous pedological, hydrological and vegetational research. One of the best indicators of the above is the ecoindicator values of the floristic composition. Materials and Methods: Phytocoenological relevés were taken in 25 localities of both stable and destabilised forest ecosystems of pedunculate oak in Žutica Forest. The principles of the Zurich-Montpellier School were applied for this process. The numerical analysis was carried out by means of SYN-TAX 2000 software. JUICE 6.3 and CANOCO 4.5 were also used to process the relevés, construct the phytocoenological tables and correlate species compositions and vegetation typeswith ecological factors. The obtained results were compared with the results of earlier ecological research. Results: Phytocoenological research revealed significant changes in the floristic composition. Ecoindicator values of plant species indicate a substantial change in ecological parameters and increased destabilisation, which leads to larger quantities of light, thermophilicity and humidity in sites. In addition, the sites are richer in nitrogen and the soil reaction becomes more basophilic, while central European species replace intermediary ones. Conclusions: The investigated plots show a regression process contrary to the normal direction of vegetation development in lowland areas. A return has been observed from the final community to transitional communities, and in some localities even to initial and pioneer communities

Assessment of efficiency of rare earth elements recovery from lignite coal combustion ash via five-stage extraction

Rare earth elements (REE) are frequently referred to as ingredients for enhancements in modern industry, as they are extensively applied in many industrial branches due to their accented electro-magnetic and optical properties. REE have end-utilizations as catalysts, magnets, and as dopants for ceramic materials. Rare earth minerals are scarce therefore the unconventional REE-containing resources such as waste materials and industrial byproducts are continuously being investigated. Coal combustion products comprise REE concentrations varying between 200 ppm and 1500 ppm. This quantity can be isolated though the extraction procedure. In this study, the five stages extraction was conducted on the coal combustion ash from the selected landfill site. The extractions of 32 elements (As, Ga, Ce, Be, Ge, Nd, Cr, Zr, Eu, Cu, Nb, Gd, Co, Mo, Dy, Li, Ag, W, Mn, Cd, Au, Ni, In, Hg, Pb, Sn, Tl, V, Sb, Th, Zn, and La) were conveyed. Chemical analyses were conducted via XRF, ICP-OES, ICP-MS, and AAS techniques. The complexity of the obtained data was examined by Principal component analysis and Cluster analysis in order to derive interconnections between quantity of elements and landfill characteristics, as well as mutual relationships among the elements of interest, and to assess the accomplishment of REE recovery from the coal ash

Evaluation of the Corrosion Depth of Double Bottom Longitudinal Girder on Aging Bulk Carriers

The longitudinal girder (LG) between fuel oil tanks (FOT) and water ballast tanks in the double bottoms of ships represent critical structural parts whose watertight nature could be harmed by corrosion, thus, causing the pollution of water ballast tanks and adjacent areas. The new common structural rules (CSR) define the minimum thickness values of structural elements and corrosion margins. The assessment of the deviations from the prescribed values during ship operation could optimize the prescribed criteria. Assuming that corrosive processes begin after four years of operation, the paper analyzes a linear model that describes the percentage of plate wear as a function of the built-in thickness of LG of FOT. The research included 20 ships and provided the database for 1918 corrosion depth values. The gauging records included the average values of the original thickness of steel plates grouped in three intervals (11–13 mm, 13–15 mm, 15–18 mm). Based on the difference between the built-in and subsequently measured values, the paper analyzes the percentage of thickness reduction due to corrosion, concerning the original plate thickness. The findings of the research should facilitate the optimization of corrosion margins and prevent potential structural collapse and pollution

Soil properties in beech-fir forests on Mt. Medvednica (NW Croatia)

Background and Purpose: Beech-fir forests in Croatia have very broad edaphic amplitude. On Mt. Medvednica they are predominantly developed on dystric cambisol, but also, to a smaller extent, on several other soil types. The purpose of this paper was to investigate soil properties in these forests and establish relations with pedogenetic factors, and especially with the bedrock and the relief. Materials and Methods: Research was based on the study of 14 soil profiles and soil samples from the horizons, and on the analysis of 39 composite samples from the surface 5 cm of soil. The following parameters were assessed from the samples: pH in water and 0.01MCaCl2, the carbonate content, and the content of biogenic elements Org C., TotalN, P,K, Ca and Mg, as well as the texture of profile samples. Results: Dominant soils in beech-fir forests on Medvednica are dystric cambisol and eutric cambisol. Most of the profiles are situated on moderately steep and steep slopes, so their A-horizon is colluvially influenced. All profiles were shallower than 100 cm, except for the stagnosol profile. The most variable parameter in the surface 5 cm was organic carbon, ranging from 40.9 to 367.2 g kg–1, whereas the pH value measured in water suspension oscillated between 3.69 and 7.21 and corresponded with the calcium content in the soil, with carbonate substrates in the central part of the range and with carbonate quantity in the soil. Conclusions: The distribution range of beech-fir forests on Mt. Medvednica is highly complex both from the pedogenetic and pedophysiographic aspect. It provides a good basis for the application of more complex models of spatial prediction of soil properties, but also for phytocoenological and ecological management profiling of beech-fir forests

Mg-Ni supported on perlite as hydrogenation catalyst: Influence of Mg and Ni content

Use of broken honeycomb-like expanded perlite as support for magnesium modified nickel catalysts in process of partial hydrogenation of sunflower oil was studied. By the use of the precipitation-deposition method, two groups of precursors were synthesized: different Ni/SiO2 mole ratios with constant Mg/Ni mole ratio 0.1, and different Mg/Ni mole ratios with constant Ni/SiO2 mole ratio 0.25. Characterizations of precursors were done (scanning electron microscopy, diffuse reflectance UV–Vis, infrared spectroscopy, N2-physisorption, temperature programmed reduction (TPR) and He-pycnometry) to determine the material differences, considering the change in morphology, structure, texture and reducibility with overall Ni and Mg content. In addition, TPR and hydrogen chemisorption were performed in order to estimate the temperature reduction range of supported precursors and the dispersion degree of nickel in reduced precursors, respectively. The interaction between Ni2+ and perlite support was established. Different reducibility and dispersion were obtained as a function of Ni/SiO2 and Mg/Ni mole ratios. After the precursor’s reduction and paraffin oil impregnation, the obtained catalysts were tested in a sunflower oil hydrogenation reaction. Catalyst activity was monitored through the decrease of the refractive index and hydrogen consumption that gave the insight that the influence on catalyst activity represents the accessibility of triacylglycerols and not always the hydrogen determined dispersion degreeProučavana je moguća upotreba ekspantiranog perlita, oblika lomljenog pčelinjeg saća, kao nosača magnezijum modifikovanog niklenog katalizatora u procesu parcijalne hidrogenizacije suncokretovog ulja. Primenom precipitaciono-depozicione metode, sintetisane su dve grupe prekursora: različitog molskog odnosa Ni/SiO2 sa konstantnim Mg/Ni molskim odnosom 0,1 i različitog Mg/Ni molskog odnosa sa konstantnim Ni/SiO2 molskim odnosom 0,25. Izvršena je karakterizacija prekursora (skenirajuća elektronska mikroskopija, difuziona refleksiona ULj-Vid, infracrvena spektroskopija, N2-fizisorpcija, temperaturski programirana redukcija - TPR i He-piknometrija) u cilju utvrđivanja razlika u materijalu, uzimajući u obzir promene u morfologiji, strukturi, teksturi i reducibilnosti ukupnog sadržaja Ni i Mg. Dodatno, TPR i hemisorpcija vodonika urađene su u cilju procene opsega temperature redukcije prekursora i stepena disperzije nikla u redukovanim prekursorima. Utvrđeno je postojanje interakcija između Ni 2+ i perlitnog nosača, a dokazana je za različite reducibilnosti i disperznosti kao funkcija Ni/SiO2 i Mg/Ni molskog odnosa. Nakon redukcije prekursora i impregnacije parafinskim uljem, dobijeni katalizatori su testirani u reakciji hidrogenizacije suncokretovog ulja. Katalitička aktivnost je praćena padom indeksa refrakcije i potrošnjom vodonika. Utvrđeno je da na katalitičku aktivnost dominantan uticaj ima dostupnost aktivnih Ni0 centara molekulima triacilglicerola, a ne njihov stepen disperzije utvrđen vodonikom