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Number of results: 52
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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 presents an approach to evaluating a building throughout its whole life cycle in relation to its sustainable development. It describes basic tools and techniques of evaluating and analysing the costs in the whole life cycle of the building, such as Life Cycle Assessment, Life Cycle Management, Life Cycle Cost and Social Life Cycle Assessment. The aim of the paper is to propose a model of cost evaluation throughout the building life cycle. The model is based on the fuzzy sets theory which allows the calculations to include the risks associated with the sustainable development, with the management of the investment and with social costs. Costs incurred in the subsequent phases of the building life cycle are analysed and modelled separately by means of a membership function. However, the effect of the analysis is a global cost evaluation for the whole life cycle of the building.
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Abstract

Results of Polish biological investigations and surveys on the state of mackerel icefish (Champsocephalus gunnari Lonnberg, 1905) stock served to undertake an attempt at an independent estimation of some of its biological parameters as well as at the assessment of its biomass and fishing mortality during 1975/76—1991/92 fishing seasons with virtual population analysis (VPA) method (using MAFFVPA programme). Laurec-Shepherd and hybrid methods were applied for the VPA tuning. Von Bertalanffy equation parameters were estimated and compared with those published earlier. F0l and F max values were assessed using Beverton and Holt model and Thompson and Bell method. Based on data from available literature the coefficient of natural mortality (M) was assumed to be 0.5. VPA results indicate that the total stock biomass (TSB) during the last 1991/92 season amounted to 34,818 tonnes and was approximately 10 times lower than in 1975/76 season. Spawning stock biomass (SSB) declined to a minimum of 7,396 tonnes in 1989/90 season. The assessment results point out to the recruitment as a major factor contributing to the stock fluctuations.
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Abstract

In this text, a critical reflection is presented on assessment practices in early childhood education, which are discussed in the context of the creation by those practices of the students’ sense of agency which, according to J. Bruner, is treated as a category of school culture. The discussion is based on the results of the recent research conducted in Poland on students’ agency and an analysis of the data collected as part of the author’s own research. The picture obtained by using the triangulation of methods and sources confirms that assessment in early childhood education strips children of the opportunity to build a sense of agency, even in terms of independent control of a task situation. The surveyed students, admittedly, are capable of a relatively independent reflection on the context of school assessment, but the world of their educational experience is limited to the incapacitating culture of the school grade. It is a culture that becomes one of the sources of children’s self-restraint in the perception of themselves as agents, perpetuating their external steerability and passivity. To change this situation, external regulations will not suffice, but only the organizing of the learning environment based on the relationship between the teacher and the student, which is free from the daily pressures of assessment and the worship of formal correctness.
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Abstract

These joints are used when the designer and contractor anticipate difficulties during the construction of overlap joints. They were not included in the PN EN 1993‒1‒8 in full scale. Resistance assessment of such joints is presented in accordance with standard rules. The results were compared with the experimental studies carried out at the “Mostostal” Centre; while the former research activities and the legitimacy of the proposed method of assessing the resistance of these joints was confirmed. This is an example of an overlap joint calculation.
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Abstract

The research of development capabilities is a fundamental of strategic issues, which has to be taken into consideration by coal mines. This is particularly difficult in the current environment, which is determined by its crisis situation. In such conditions, it is necessary to take difficult decisions, and serious, strategic challenges into account, which allow for the crisis to be overcome, for the renewal and economic effectiveness of the operation of these coal mines, which have potential to grow, and closing the coal mines, which have not potential to grow. Due to the effects of such decisions, which concern not only coal mines but also the Silesian region, it is essential to prepare information to support them and promote rational choices. This is related to the issue of research for development possibilities. The article presents considerations related to the subject of research for development possibilities of coal mines in a crisis situation. Taking the results of literature study into account, the model of research process was developed, and identified the research issues concerning the following: - the identification of external factors which determine the possibility of development of the Polish mines and drawing a schedule of their changes in the future, - the identification of internal factors which determine the possibility of development of the Polish mines, - developing a way for the assessment of the development potential of the coal mines, to show appropriate strategic options and action programmes for these options, - determining possible strategic options and corresponding schedules, appropriate for the specific nature of the mines. The proposition of their solutions, which were obtained in the process of using the specific methods and research tools, allowed the guidelines in terms of research of development capabilities of coal mines to be presented.
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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

A village on the outskirts of a city. An analysis and assessment of the west part of Inowrocław for the purposes of spatial planning, The article presents results of a research concerning the landscape of the west part of Uzdrowisko Inowrocław which is characterized by a rural origin and physiognomy, despite being located in the city. The goal of the paper was to identify the resources of that landscape, determine the pace of its transformation, its value, and indicate the possible directions of development. The research consisted in a landscape diagnosis concerning physiognomy aspects in various dimensions (composition, panoramic, and planning), taking advantage of methods used in landscape architecture and urban design. The execution allowed to formulate guidelines concerning the protection and formation of the researched landscape. The goal was also to determine the usefulness of the used model of research proceedings in practice, including indicating the possibilities of implementing the identified results in spatial planning on a local scale. The work has a case study character which conclusions may be helpful in analyzing similar areas and their landscapes.
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Abstract

For the use of acoustic assessment of machinery, a global index of acoustic quality has been developed. Acoustic quality index is considered as a product of the following partial indices: sound power index, index of distance between the workstation and the machine, radiation directivity index, impulse and impact noise index and noise spectrum index. Each partial index always assumes positive value. If the value of global index does not exceed 1, the noise of the assessed machine will not exceed the admissible value of A-weighted sound pressure level at the workstation. Experimental tests were carried out in order to determine the values of global indices for a group of engine-generators, with the use of inversion method allowing for the determination of sound power level. The correctness of the determined values of indices was confirmed by the results of A-weighted sound pressure level measurements, at the hypothetically assumed workstations in simulated in situ conditions.
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Abstract

The use of ultrasonic energy has created versatile possibilities of their applications in many areas of life, especially in hydro location and underwater telecommunications, industry and medicine. The consequence of a widespread use of high intensity ultrasonics in technology is the increased number of people who are exposed to such ultrasonic noise. Therefore it is important to determine the types of machines and other devices that are responsible for the emission of ultrasonic noise (10-40 kHz of central frequencies of one-third octave bands) as harmful and annoying hazard in the work environment. This paper presents ultrasonic noise sources frequently used in industry and preventive measures reducing the exposure to ultrasonic noise. Two types of ultrasonic noise sources have been distinguished: machines and other devices used to carry out or improve production processes, the so-called technological sources and sources in which ultrasonic noise exists as a non-intentional result of operation of many machines and systems, the so-called non-technological sources of ultrasonic noise. The emission of SPL has been determined for each groups of devices based on own measurement results.
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Abstract

Nanotechnology has been widely applied in agriculture, and understanding of the mechanisms of plant interaction with nanoparticles (NPs) as environmental contaminants is important. The aim of this study was to determine the effects of foliar application of cobalt oxide (Co3O4) NPs on some morpho-physiological and biochemical changes of canola (Brassica napus L.) leaves. Seeds were sown in plastic pots and grown under controlled conditions. Fourteen-day-old seedlings were sprayed with different concentrations of Co3O4 NPs (0, 50, 100, 250, 500, 1000, 2000, and 4000 mg L-1) at weekly intervals for 5 weeks. Growth parameters of the shoot (length, fresh and dry weights) were stimulated by low concentrations of Co3O4 NPs (50 and 100 mg L-1) and repressed by higher concentrations. Similar trends were observed in photosynthetic pigment contents. The results indicated that high concentrations of Co3O4 NPs increased lipoxygenase (LOX) activity and the malondialdehyde (MDA), hydrogen peroxide (H2O2), and dehydroascorbate (DHA) contents, but reduced the membrane stability index (MSI), ascorbate (ASC), and glutathione (GSH). Despite the increase of antioxidant capacity (DPPH) and the accumulation of nonenzymatic antioxidants (total flavonoids and flavonols) and osmolytes (proline, glycine betaine (GB) and soluble sugars) at high concentrations of Co3O4 NPs, the growth and photosynthesis were reduced. The defence system activity did not seem to be sufficient to detoxify reactive oxygen species (ROS). Altogether, high concentrations of Co3O4 NPs showed a phytotoxic potential for canola as an oilseed crop.
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Abstract

A dynamic economy contributes to the increase in the number of workers exposed to mechanical vibration caused by machines and transport equipment. As the means of transport are insufficiently recognised sources of mechanical vibrations, this article presents the results of whole-body and hand-arm vibration tests of 30 most common means of in-house transport. An analysis of vibration signals recorded at each workstation according to PN-EN 14253 and PN-EN ISO 5349 made it possible to determine the weighted values of components of directional vibration acceleration and the values of daily vibration exposure A(8). In order to assess exposure to whole-body and hand-arm vibration at the tested workstations of in-house transport, indices of vibration hazard related to admissible values, the total evaluation index (developed in a previous study at CIOP-PIB) and a three-degrees scale for assessing exposure to vibrations were used. The assessment showed that the workstations were a major hazard. Vibration hazards at all those workstations were classified as either medium or high.
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Abstract

In parallel to the ultrasonic noise assessment procedures and research activity in the field there have appeared several papers in the domain of so called high-frequency audiometry which covers the range of frequencies 8-20 kHz. They are important for recognizing the harmfulness and hazard of the audible high frequency sound components in the same range as the one of the low frequency ultrasonic noise. On the other hand there exists a certain inconsequent situation in the general approach to the problem of ultrasonic noise hazard assessment in work places environment which concerns the convention to include the frequency range of 10-20 kHz to the domain of ultrasonics. The range consists of one third octave bands of central frequencies: 10, 12.5, 16, 20 kHz and conventionally is called low frequency ultrasonic noise though at least the components of the two lowest bands are naturally audible by a majority of population (mainly young people).The paper presents a discussion related to some achievements of the two domains and some conclusions which could be useful for a more consequent description of the subject and could be taken into account in the future regulations for the ultrasonic noise assessment in work places environment.
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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

The paper presents a new method of lifetime calculations of steam turbine components operating at high temperatures. Component life is assessed on the basis of creep-fatigue damage calculated using long-term operating data covering the whole operating period instead of representative events only. The data are analysed automatically by a dedicated computer program developed to handle big amount of process data. Lifetime calculations are based on temperature and stress analyses performed by means of finite element method and using automatically generated input files with thermal and mechanical boundary conditions. The advanced lifetime assessment method is illustrated by an example of lifetime calculations of a steam turbine rotor.
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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 the paper toxicity assessment of hospital wastewaters samples was performed using direct-contact tests consisting of five species, which represent three different trophic levels of the food chain. IC50 or EC50 values were estimated for each tested organism: Pseudokirchneriella subcapitata IC50/72h 18.77%, Daphnia magna EC50/48h 20.76%, Thamnocephalus platyurus EC50/24h 22.62%, Artemia salina EC50/24h 59.87% and Vibrio fisheri EC50/15min 46.17%. Toxic potential of hospital wastewater was described using a system of wastewater toxicity classification. The toxic units (TU) values estimated for each test indicate that hospital wastewaters are toxic (Class III). The variable results of the tests’ sensitivity confirmed the need of application of microbiotests battery with organisms of different trophic levels.
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Abstract

In the article the author discusses peculiarities of three areas of psychologists’ professional activity: conducting scientific research, educating new generations of psychologists, and having a private practice. He particularly stresses the significance of empirical testability of theories for correct and ethical assessment practice (according to Evidence-Based Assessment standard) and therapeutic practice (according to Evidence-Based Practice in Psychology standard). The author also explores the cultural immersion of psychological activity.
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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

One of the important issues concerning development of spatial data infrastructures (SDIs) is the carrying out of economic and financial analysis. It is essential to determine expenses and also assess effects resulting from the development and use of infrastructures. Costs and benefits assessment could be associated with assessment of the infrastructure effectiveness and efficiency as well as the infrastructure value, understood as the infrastructure impact on economic aspects of an organisational performance, both of an organisation which realises an SDI project and all users of the infrastructure. The aim of this paper is an overview of various assessment methods of investment as well as an analysis of different types of costs and benefits used for information technology (IT) projects. Based on the literature, the analysis of the examples of the use of these methods in the area of spatial data infrastructures is also presented. Furthermore, the issues of SDI projects and investments are outlined. The results of the analysis indicate usefulness of the financial methods from different fields of management in the area of SDI building, development and use. The author proposes, in addition to the financial methods, the adaptation of the various techniques used for IT investments and their development, taking into consideration the SDI specificity for the purpose of assessment of different types of costs and benefits and integration of financial aspects with non- financial ones. Among the challenges are identification and quantification of costs and benefits, as well as establishing measures which would fit the characteristics of the SDI project and artefacts resulting from the project realisation. Moreover, aspects of subjectivity and variability in time should be taken into account as the consequences of definite goals and policies as well as business context of organisation undertaking the project or using its artefacts and also investors.
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Abstract

During the IceAGE ( Icelandic marine Animals – Genetics and Ecology ) expeditions in waters around Iceland and the Faroe Islands in 2011 and 2013, visual assessments of habitats and the study of surface sediment characteristics were undertaken in 119–2750 m water depth. Visual inspection was realized by means of an epibenthic sled equipped with a digital underwater video camcorder and a still camera. For determination of surface sediment characteristics a subsample of sediment from box corer samples or different grabs was collected and analyzed in the lab. Muddy bottoms predominated in the deep basins (Iceland Basin, Irminger Basin, deep Norwegian and Iceland Seas), while sand and gravel dominated on the shelves and the ridges, and in areas with high currents. Organic contents were highest in the deep Norwegian and Iceland Seas and in the Iceland Basin, and at these sites dense aggregations of mobile epibenthic organisms were observed. Large dropstones were abundant in the Iceland Sea near the shelf and in the Denmark Strait. The dropstones carried diverse, sessile epibenthic fauna, which may be underestimated using traditional sampling gear. The paper supplies new background information for studies based on IceAGE material, especially studies related to ecology and taxonomy.
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Abstract

This article provides a comparison of a three methods that can be used for calculating effective coverage of image quality assessment database. The aim of this metric is to show how well the database is filled with variety of images. For each image in the database the Spatial Information (SI) and Colorfulness (CF) metric is calculated. The area of convex hull containing all the points on SI x CF plane is indication of total coverage of the database, but it does not show how efficiently this area is utilized. For this purpose an effective coverage was introduced. An analysis is performed for 16 databases - 13 publicaly available and 3 artificial created for the purpose of showing advantages of the effective coverage.
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Abstract

Improving the technology for determining the investment attractiveness of urban land requires the development and implementation of an integrated assessment method. In this context, the formation of a system of indicators used for the integral assessment is very important. Based on the two-level system of factors proposed in the article, which influence the formation of investment attractiveness of urban land and using a hierarchical classification method, an appropriate system of indicators is constructed. The transition from factors to indicators is ensured by the established causal dependence, which characterizes the causal relationships between factors and functional-planning, territorial indicators, indicators of engineering and territory improvement, indicators of ecology, historical and cultural significance. In article it is proposed to consider the information support as a set of functional-planning, territorial, engineering support and improvement of the territory, environment, ecology, historical and cultural indicators, which are formed on the basis of normative legal acts, systematization of theoretical and methodological provisions, considering technological features and factors, which affect the investment attractiveness of land. Considering the existing directions for the implementation of technology for assessing the investment attractiveness of urban land, the economic, spatial, complex, multifactorial, rating approaches and approach based on the tools and results of mathematical modelling, considering technical, environmental, social and economic factors, which influence the investment attractiveness of urban land have been proposed.
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Abstract

The condition of the conical surface of the needle and seat in a fuel atomizer can be assessed by using the acoustic emission method. The assessment of this conical tribological pair can be performed by up-to-date measurement methods that substantially enhance the quality of evaluating the technical condition of conical surfaces of the atomizer needle and seat.
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