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Number of results: 11
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Abstract

Construction risk assessment is the final and decisive stage of risk analysis. When highly changeable conditions of works execution are predicted, risk should be evaluated in the favorable, moderate, and difficult random conditions of construction. Given the random conditions, the schedule and cost estimate of the construction are developed. Based on these values, the risk of final deadline delay and the risk of total cost increase of construction completion are calculated. Next, the charts of the risks are elaborated. Risk changes are shown in the charts and are analyzed in the range [1, 0].
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Abstract

The paper concerns the assessment of blackout hazards in the power systems. On the basis of statistical data from more than one hundred failures in power systems that affected the world in the last fifty years, the analysis was carried out regarding the number of people affected by a blackout, power losses in the system, duration of a failure and its direct causes. The paper also describes the methodology of risk analysis and vulnerability analysis of the extraordinary events occurrence in electrical power systems resulting in failures. The structure of risk analysis was based on the bow tie model, identifying threats, unwanted events, barriers and consequences of a system failure. Moreover, particular attention was drawn to the impact of the power reserve deficit in the Polish Power System in the coming years on the increase in the risk of a blackout failure.
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Abstract

This work is a contribution to a normative approach of noise assessment in the professional environment. It permits the identification of the affected workstations on the one hand and on the other hand it constitutes an important support to the preoccupations of the impact study on the environment in plants. It also informs us on the adequate preparation of the procedures required by the Environmental Management System (ISO 14001) being implemented in steel-making complex ArcelorMittal Algeria. It constitutes an answer to the recommended environmental politics. The proposed calculation methods are verified according to the recognized sources (ISO 9612, 2009) and the results will be estimated in relation to the legal thresholds recommended by international bodies. The methodology for measuring the noise exposure levels has been done according to the following steps: work analysis; selection of measurement strategy; measurements; error handling and uncertainty evaluations; calculations; and presentation of results. This will lead us to an implementation of a corrective and preventive action plan intended to master this occupational risk carrying prejudice to the health of the workers.
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Abstract

This paper addresses the issue of antibacterial drugs, estrogens and cytostatic drugs’ presence in surface waters and their influence on animals. The ecotoxicity and the impact of three active compounds: ciprofloxacin, 17α-ethinylestradiol and 5-fluorouracil on protozoa, crustaceans and fish were examined. Acute tests (crustaceans’ immobilization test, fish survival test, enzymatic test on Daphnia magna) and chronic tests (growth test on protozoa, reproduction test on crustaceans and juvenile growth test on two species of fish) were performed. Acute toxicity studies revealed diversified species - sensitivity to the tested compounds. Crustaceans Artemia salina were the most resistant to all three pharmaceuticals. Fish also demonstrated low sensitivity to ciprofloxacin and 5-fluorouracil (LC(EC)50-96h > 100 mg/l). In the survival tests, the greatest harm in respect to fish and crustaceans was demonstrated by 17α-ethinylestradiol, and in the enzymatic tests - by ciprofloxacin. In all chronic tests, the toxic effects of drugs were proven. Tested compounds limited reproduction of crustaceans and growth of protozoa and fry. The risk assessment, conducted on the basis of the PEC/PNEC quotient, showed a significant risk in relation to aquatic animals caused by the presence of 17α-ethinylestradiol and 5-fluorouracil in concentrations detected in surface waters.
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Abstract

In this article, authors analyze methods of the analysis of data integrity, security and availability loss results for business processes. Assessing those results, one can judge the importance of a process in organization; thus, determine which business process requires more attention. The importance of those processes can be determined with Business Impact Analysis (BIA). In article, first phase of BIA is presented – in specific, a construction of Business Impact Category Tables, Loss Levels and process weight calculation methods. A variety of weight calculating methods is presented. Authors also present their proposed method – square sum percentage – as a solution eliminating problems of other weight calculation methods in business impact analysis.
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Abstract

Environmental risks associated with Co, Cr, Cu, Mn, Ni, Pb, V and Zn in street dust collected from Baotou, a medium-sized industrial city in a semi-arid area of northwest China, were assessed by using enrichment factor and the potential ecological index. Their spatial distributions and sources in the dust were analyzed on the basis of geostatistical methods and multivariate statistical analysis, respectively. The results indicate that street dust in Baotou has elevated heavy metal concentrations, especially of Co, Cr, Cu, Pb and Zn. Co in the dust was significantly enriched. Cr and Pb were from moderate to significant enrichment. Cu and Zn were from minimal to moderate enrichment, whereas Mn, Ni and V in the dust were from deficient to minimal enrichment. The ecological risk levels of Co and Pb in the dust were moderate to considerable and low to moderate, respectively, whereas those of other heavy metals studied in the dust presented low ecological risk. Different distribution patterns were found among the analyzed heavy metals. Three main sources of these heavy metals were identified. Cr, Mn, Ni and V originated from nature and industrial activities. Cu, Pb and Zn derived mainly from traffic sources, and Co was mainly from construction sources.
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Abstract

The influence and the potential risk due to hidden faults of a relay protection system on power supply in distribution systems are paid more and more attention to. A probability analysis method is used to analyse fault characteristics and action mechanism of dominant faults, hidden misoperation and non-operation of the relay protection systems, and failure probability model of relay protection system is constructed and simplified. The effects of dominant faults, hidden misoperation and non-operation of the relay protection systems on the reduced power supply load power are analysed, and a probabilistic model for reduced power supply load power is constructed by three parts corresponding to dominant faults, hidden misoperation and non-operation. A probability calculation method of power supply risk occurrence due to hidden faults of relay protecttion system is proposed considering the fault probability of the relay protection systems, the frequency of the hidden faults occurring in operation period, the reduced power supply load power or load power outage, and the connection mode of the in-lines, out-lines and transformers in a substation. The feasibility and applicability of the proposed method for estimation of risk value probability of the relay protection systems is verified by two studied examples.
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Abstract

Uranium concentrations in groundwater taken from private drilled wells have been never determined in Poland, implying a lack of available data to quantify the human exposure to U through drinking water consumption, especially in rural areas influenced by mining activities. The main aim of the study was the assessment of human health risk related to the consumption of well waters containing U, collected from selected rural areas of the Lower Silesian region (Poland). The random daytime (RDT) sampling method was applied to the collection of well waters from three control study areas (CSA): Mniszków (CSA-A), Stara Kamienica/M. Kamienica/Kopaniec (CSA-B) and Kletno (CSA-C). The analyses of RDT samples were performed by validated method based on inductively coupled plasma mass spectrometry (ICP-MS). Uranium concentration ranges in well waters and the estimated geometric means for individual control study areas were: 0.005-1.03 μg/L and 0.052 μg/L (CSA-A), 0.027-10.6 μg/L and 0.40 μg/L (CSA-B), and 0.006-27.1 μg/L and 0.38 μg/L (CSA-C). The average and individual chronic daily intakes (CDI) of U by drinking water pathway (adults/children) were in the ranges of: 0.0017-0.013/0.0052-0.040 μg · kg-1 · day-1 and 0.0002-0.90/0.0005-2.71 μg · kg-1 · day-1. The average %TDI and ranges of individual %TDI (adults/children) were: 0.17%/0.52% and 0.02-3.4%/0.05-10.3% (CSA-A), 1.3%/4.0% and 0.09-35%/0.27-106% (CSA-B), and 1.3%/3.8% and 0.02-90%/0.06-271% (CSA-C). The estimated average CDI values of U through well water are significantly lower than the TDI (1 μg · kg-1 · day-1), while for individual CDI values the contribution to the TDI can reach even 90% (adults) and 271% (children), indicating essential human health risk for children consuming well water from private drilled wells located in CSA-B and CSA-C (5.3% of total number of samples collected).
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Abstract

The difficulty of innovation risk assessment makes it necessary to use a multi-criteria analysis. Innovative projects are related to unstructured problems and the uncertainty, therefore, the use of fuzzy logic in the innovation risk assessment is analyzed. This paper proposes a method of determining the weights of criteria in order to innovation risk assessment. The weights are determined by 5 general criteria and 14 detailed criteria of innovation risk assessment. The proposed method is an extension of the fuzzy AHP method. The extension consists in taking into consideration the group decision-making approach with experts’ psychological conditions. The groups of experts have been chosen based on an elaborated form. The form makes it possible to characterize the persons within the scope of different psychological conditions. The proposed method provides objective and rational decision-making. The paper presents also a comparison of results with the fuzzy AHP method without the group decision making. The weights obtained by the proposed method are more diversified and bring out the most important criteria.
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Abstract

The article presents a shock safety model of an indirect contact with a low-voltage electric device. This model was used for computations and analyses concerning the following: the probabilities of appearance of the particular shock protection unreliability states, electric shock states (ventricular fibrillation), contributions of the unreliability of different shock protection elements to the probability of occurrence of these states, as well as the risk of electric shock (and the shock safety), and contributions of the intensity of occurrence of damages to different shock protection elements to this risk. An example of a possibility to reduce the risk of an electric shock through changing the intensity of occurrence of damages to the selected protection elements was provided.
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Abstract

The article describes a shock safety modeling method for low-voltage electric devices, based on using a Bayesian network. This method allows for taking into account all possible combinations of the reliability and unreliability states for the shock protection elements under concern. The developed method allows for investigating electric shock incidents, analysing and assessing shock risks, as well as for determining criteria of dimensioning shock protection means, also with respect to reliability of the particular shock protection elements. Dependencies for determining and analysing the probability of appearance of reliability states of protection as well as an electric shock risk are presented in the article.
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