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Number of results: 12
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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

This article aims to identify potential risk factors affecting the implementation and synchronisation of surveying and construction works during building and operation of roads. The task was executed on the basis of literature studies and experience. The article is an introduction to the research that has been conducted by the authors on the reasonably precise index of factors which one may deal with during the implementation of facilities of this type. The raised issue is crucial for financial and time reasons, but what is important in the roads construction - also for social ones, as prolonged traffic disruption adversely affects the environment.
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Abstract

Statystyczny Polak spędza przeciętnie około 20% swojego życia na wykonywaniu pracy zawodowej, stąd działania pracodawcy, jego służb bhp i organów państwowej kontroli skupiają się nad zapewnieniem możliwie jak najbardziej bezpiecznych warunków środowiska pracy. Całkowite wyeliminowanie z otoczenia pracownika czynników, będących źródłem zagrożeń niebezpiecznych, szkodliwych bądź uciążliwych, w wielu przypadkach jest zadaniem trudnym, a często niemożliwym. Wynika to z faktu, iż dany czynnik stanowić może podstawową składową procesu technologicznego i nie może zostać wykluczony, tak jak to ma miejsce w przypadku prac szczególnie niebezpiecznych, np. podczas używania materiałów wybuchowych przeznaczonych do użytku cywilnego. W takim wypadku szczegółowa identyfikacja oraz ocena poziomu zagrożeń, uwzględniająca wiedzę ekspercką z zakresu stosowanych środków strzałowych oraz technologii, stanowi przyczynek do wzrostu poziomu bezpieczeństwa pracownika pomimo stosowania niebezpiecznych substancji, niebezpiecznych środków pracy czy niebezpiecznych technologii. W trakcie eksploatacji metodą odkrywkową jednym z najczęściej stosowanych sposobów odspojenia i rozdrobnienia złoża skalnego jest użycie materiałów wybuchowych. Taka technika urabiania powoduje konieczność zatrudnienia pracowników na stanowiskach specjalistycznych, na których występuje wiele zagrożeń tzw. ogólnokopalnianych oraz tych wynikających z bezpośredniej ekspozycji na czynnik niebezpieczny, jakim są środki strzałowe. W niniejszym artykule przedstawiono szczegółową identyfikację zagrożeń na stanowiskach związanych z używaniem materiałów wybuchowych, uwzględniającą wykonywane czynności podczas realizacji robót strzałowych w górnictwie odkrywkowym oraz zróżnicowanie tych zagrożeń w przypadku stosowania różnych systemów inicjowania materiałów wybuchowych. Po zidentyfikowaniu zagrożeń dokonano ich hierarchizacji z wykorzystaniem metody Analytic Hierarchy Process (AHP), która jest jedną z technik wielokryterialnego podejmowania decyzji, umożliwiającą bezpośrednie porównanie między sobą i szeregowanie według przyjętych kryteriów analitycznych. Na podstawie wyników przeprowadzonych analiz sporządzono ocenę macierzową dla wyznaczenia poziomu ryzyka zagrożeń dla specjalistycznego stanowiska pracy w ruchu odkrywkowego zakładu górniczego – górnika strzałowego.
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Abstract

The purpose of this article is to present the preparation of Project Risk Assessment Methodology and its mitigation in complex construction projects. The main text provides a summary of the approach, the method used and the findings. The conclusions have been drawn that the proper tools for quantifying risks have to be based on the criteria specific for mathematical statistic and probability or at least fuzziness. Function, which makes possible to categorize any risks into one of the five categories, is a combination of probability and the impact on one of the items: people and their safety or budget, cost, schedule and planning or quality and performance. An attempt was made to express numerically the relationship between risks impacts and their level of likelihood. Also, a method of associating the influence of projects risks impacts on the extent of the likelihood of project risk occurrence which makes possible to determine the direction and the strength of this relationship was presented.
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Abstract

Praktyka badawcza w biomedycynie ma fundamentalne znaczenie dla rozwoju bardziej bezpiecznych i skutecznych metod leczniczych. Praktyka ta ma więc ogromną wartość społeczną, jest jednak działalnością moralnie problematyczną, ponieważ jej realizacja wymaga narażania ludzi na ryzyko dla dobra innych – nauki, przyszłych pacjentów i społeczeństwa jako całości. Problem ten jest szczególnie widoczny w przypadku badań niemających potencjału dostarczenia uczestnikom bezpośrednich korzyści zdrowotnych – tzw. badaniach „nieterapeutycznych”. Istnieje międzynarodowy konsensus co do tego, że prowadzenie badań „nieterapeutycznych” na osobach niezdolnych do wyrażenia zgody jest dopuszczalne tylko wtedy, gdy ryzyko związane z udziałem w takich badaniach nie przekracza pewnego minimalnego progu. Brak jednak zgody co do tego, czy powinien istnieć nieprzekraczalny próg ryzyka badawczego, na jakie mogą narażać się osoby kompetentne za swoją zgodą. Celem pracy jest przedstawienie argumentów etycznych przemawiających za wyznaczeniem maksymalnego dopuszczalnego poziomu ryzyka w badaniach „nieterapeutycznych” z udziałem ochotników. Przeanalizowane zostają także sposoby wyznaczenia takiego maksymalnego progu ryzyka, zawarte w dokumentach regulacyjnych oraz sformułowane w literaturze bioetycznej.
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Abstract

In Poland, it often happens that construction objects are subject to demolition work for different reasons. Demolition, according the Construction Law, is defined as a type of construction works and, as such, represents a particular type of construction project. As in other construction projects, a very important phase, in addition to execution of the works, is to prepare, design and plan demolition works. Some demolition activities are covered by appropriate regulations and can be described as typical. On the other hand the technical side of demolition works depends on many factors such as: the type of building, its age, technical condition, type of construction, etc. This article covers the analysis of the stages and tasks in the preparatory phase of the building demolition. This work will also present a description of the tasks carried out during the demolition works based on the example of a historic tenement house located in Krakow. This analysis aims to identify implementation problems and sources of risk that may occur during this type of construction work.
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Abstract

Risks pertaining to construction work relate to situations in which various events may randomly change the duration and cost of the project or worsen its quality. Because of possible significant changes of random events, favorable, moderate, and difficult conditions of construction work are considered. It is the first stage of the construction risk analysis. The probabilistic parameters of construction are identified and described by using the design characteristics model of the structure and the construction technology model. The first describes the probabilistic properties of the structure execution's technology. The second describes the probabilistic properties of the works execution. Both models contain basic probabilistic data for scheduling, cost estimating, and risk assessment of the construction.
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Abstract

During the planning and controlling of the construction process, most attention is focu sed on risk analysis, especially in the context of final costs and deadlines of the investment. In this analysis, the primary and most significant concern is the proper identification and quantification of events, which on a certain level of probability may affect the development process. This paper presents the result of a risk analysis for a particular building object, made after completion of the investment and accepting it for use. Knowledge of the planned values and the actual investment process allowed for the identification of the events and their effects that in this case have significantly disrupted the investment process. The limited total cost of the investment project in question had a considerable impact on the progress of the project execution. Despite three transitions of administrative procedures, the opening date of the shopping centre was delayed by only three weeks.
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Abstract

This article shows incidents associated with the use of gas as an energy carrier. It presents selected incidents which have occurred in Poland and around the world in recent decades. Based on this, consequences of gas and air mixture explosions were analysed as well. The article presents the main causes of gas incidents which have taken place, as per instances which are similar worldwide. Incidents associated with the use of gas are not frequent, but at the same time very tragic as they often lead to illness or even death. In Poland, in the last twenty years, construction area disasters caused by gas explosions account for only 5% of all which have occurred, but the number of fatalities resulting from these cases is approximately 14%. The number of individuals injured reached 39% of all construction disaster victims. Considering all these facts, it is necessary to undertake wide preventive measures in order to increase safety in the use of gaseous fuels.
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Abstract

Overseas mining investment generally faces considerable risk due to a variety of complex risk factors. Therefore, indexes are often based on conditions of uncertainty and cannot be fully quantified. Guided by set pair analysis (SPA) theory, this study constructs a risk evaluation index system based on an analysis of the risk factors of overseas mining investment and determines the weights of factors using entropy weighting methods. In addition, this study constructs an identity-discrepancycontrary risk assessment model based on the 5-element connection number. Both the certainty and uncertainty of the various risks are treated uniformly in this model and it is possible to mathematically describe and quantitatively express complex system decisions to evaluate projects. Overseas mining investment risk and its changing trends are synthetically evaluated by calculating the adjacent connection number and analyzing the set pair potential. Using an actual overseas mining investment project as an example, the risk of overseas mining investment can be separated into five categories according to the risk field, and then the evaluation model is quantified and specific risk assessment results are obtained. Compared to the field investigation, the practicability and effectiveness of the evaluation method are illustrated. This new model combines static and dynamic factors and qualitative and quantitative information, which improves the reliability and accuracy of risk evaluation. Furthermore, this evaluation method can also be applied to other similar evaluations and has a certain scalability.
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Abstract

The extraction of mineral deposits is usually charged with additional taxes or royalty fees that go beyond the general income tax. As a rule, countries prefer stable sources of fiscal revenues based on the volume of raw material extraction, and investors prefer models based on profit tax, i.e. taking operating costs and risks lower than the expected profitability of the project into account. As a rule, too high a burden for the mining sector affects investors’ decisions regarding the introduction of new investments. There are a number of examples where excessive fiscal burdens force investors to move to countries with more favorable tax systems. An analysis of various forms of taxation of mining enterprises around the world has been presented and compared with the system implemented in Poland. Usually, the countries that apply the royalty fee in the mining sector at the same time introduce a number of adaptation mechanisms. This is crucial for new investments due to the fact that they may to some extent compensate for the high costs of transition from the investment to the operational phase. In most cases, several incentive mechanisms are used at the same time, e.g. the accelerated settlement of investment expenditures and the unlimited settlement of losses. The copper and silver mining tax introduced in Poland increased the discounted effective tax rate (ETR) from 38.5% to 89% for the entire investment period, which resulted in a 11-year return on investment, as well as a drop in the internal rate of return (IRR).There are currently no mechanisms in Poland which would balance the burden of this tax for a new investor. In order to balance the extraction tax for certain minerals in terms of the IRR and ETR key indicators, the introduction of several adaptation mechanisms has been proposed. For new investments the most essential mechanism is the preferential settlement of capital expenditures incurred in the pre-production phase of an investment. The others include accelerated amortization, the ability to deduct certain expenses for the exploration phase from the tax base, along with an extended tax loss settlement period, or a mechanism for deducting a certain percentage of investment expenses directly from the tax.
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Abstract

In the over 150 years of hydrocarbon history, the year 2017 will be one of the many similar. However, it will be a breakthrough year for liquefied natural gas. In Asia, China grew to become the leader of import growth, becoming the second world importer, overtaking even South Korea and chasing Japan. The Panama Canal for LNG trade and the “Northern Passage” was opened, so that Russian LNG supplies appeared in Europe. The year 2017 was marked by a dramatic shortening of the length of long-term concluded contracts, their shorter tenure and reduction of volumes – that is, it was another period of market commoditization of this energy resource. The article describes the current state of LNG production and trade till 2018. It focuses on natural gas production in the United States, Qatar, Australia, Russia as countries that can produce and supply LNG to the European Union. The issue of prices and the contracts terms in 2017 was analyzed in detail. The authors stress that the market is currently characterized by an oversupply and will last at least until mid–2020. Novatek, Total – Yamal-LNG project leaders have put the condensing facility at 5.5 million tons into operation. The Christophe de Margerie oil tanker was the first commercial unit to cross the route to Norway and then further to the UK without icebreakers and set a new record on the North Sea Road. In 2017, the Russian company increased its share in the European gas market from 33.1 to 34.7%. In 2017, Russia and Norway exported record volumes of „tubular” – classic natural gas to Europe (and Turkey), 194 and 122 billion m3 respectively, which is 15 and 9 billion m3 more natural gas than in 2016. The thesis was put forward that Russia would not easily give up its sphere of influence and would do everything and use various mechanisms, not only on the market, that it would simply be more expensive and economically unprofitable than natural gas. It was also emphasized that the pressure of the technically possible and economically viable redirection to European terminals of methane carriers landed in the American LNG, results in Gazprom not having a choice but to adjust its prices. The Americans, but also any other supplier (Australia?) can simply do the same and this awareness alone is enough for Russian gas to be present in Europe at a good price.
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