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.
As a machining technology, welding can cause serious accidents by overloading or operation mistakes. Through analyzing the causes of various welding accidents, we found that the major cause for damage imposed after welding parts are loaded is the fracture of materials. Therefore, studying the influence of welding residual stress on the fracture property of materials is of great significance. This paper applied the digital image correlation technique to study the fracture property of welding parts under the influence of welding residual stress. In addition, standard parts and welding parts were selected to carry out a contrast experiment. Room temperature tensile tests were performed on both standard parts and test pieces after residual stress measurement. Using displacement field and strain field data obtained through VIC-2D software, the stress intensity factor around the crack tip of each specimen under the conditions of small load was calculated and corresponding analysis was carried out.
The correlation-regression method, as one of the indirect sampling methods, is only sporadically used in geological and mining activities. Theoretically, it should be particularly useful for predicting the content of some chemical components in limestone and marl deposits due to the correlation between them. The results of simple and multiple correlation and regression analysis for 5 selected components (CaO, SiO2, Al2O3, MgO, and SO3), determined in samples from exploratory boreholes and blast holes carried out in the Barcin-Piechcin-Pakość deposit, are presented in the article. The determination coefficients were used as a measure of the correlation power and the quality of the regression models. A very strong linear correlation between CaO and SiO2 content and strong linear correlations between CaO and Al2O3 and SiO2 with Al2O3 have been found. The correlation relationships of the remaining pairs of oxides are weak or very weak and do not provide a basis for prediction of their content based on regression models binding them with the content of other components. The use of nonlinear models for these pairs of oxides results in only a slight improvement in the quality of regression, insignificant from a practical point of view. The application of multiple regression models, linking the content of the mentioned components (with the exception of CaO), leads to similar conclusions. Compared to the determination coefficients of a simple linear correlation, a strong increase in determination coefficients obtained in two cases was found to be artificial and caused by a correlation between the content of the selected components acting as independent variables. From the geological and mining point of view, the results of the analysis indicate the possibility of a fully reliable prediction of SiO2 content and the limited reliability of the Al2O3 content prediction when the CaO content is determined using simple linear regression models.
Interferometria sejsmiczna jest dynamicznie rozwijającą się metodą, której pierwsze zastosowania sięgają początków obecnego stulecia. Aktualnie znajduje coraz szersze zastosowanie w zagadnieniach m.in. obrazowania głębokich struktur ziemi oraz utworów przypowierzchniowych, monitorowania procesów wulkanicznych oraz analizowania wpływu silnych trzęsień ziemi na obiekty budowlane. Metoda ta pozwala na odtworzenie odpowiedzi impulsowej tzw. funkcji Greena ośrodka pomiędzy parą odbiorników na podstawie zarejestrowanych w tym samym czasie sejsmicznych pól falowych na tych odbiornikach. W wyniku odpowiednich operacji matematycznych metoda ta zamienia zarejestrowane na odbiornikach koherentne fale sejsmiczne o nieznanym czasie oraz miejscu ich wzbudzenia na układ tzw. wirtualnych źródeł emitujących sejsmiczne pole falowe z dowolnego odbiornika. W artykule przedstawiono fizyczne uzasadnienie wyników eksperymentu akustyki odwróconego czasu (ang. time-reversed acoustics) według Derode i in. (2003), które jest zarazem wytłumaczeniem metody interferometrii sejsmicznej. Eksperyment laboratoryjny w pierwszym etapie polegał na rejestracji akustycznego pola falowego wyemitowanego na brzegu naczynia wypełnionego cieczą i stalowymi prętami. Następnie rejestracje zostały odwrócone w czasie i wysłane powtórnie do wewnątrz naczynia i odebrany po przeciwnej stronie. Zarejestrowany na końcu sygnał okazał się zbliżony do sygnału wyemitowanego, pomimo przejścia przez ośrodek wielokrotnie rozpraszający. Doświadczenie to uzasadniono wykorzystując technikę korelacji wzajemnej (ang. cross-correlation), zasadę superpozycji pola falowego oraz zasadę wzajemności Rayleigha.
According to Nicolai Hartmann, the correlativistic prejudice is the claim that a being must be a correlate of a subject, and this, he argues, is the main prejudice of Husserl’s phenomenology taken as an eidetic science of transcendental consciousness with its correlates. In contrast to Hartmann, the author of this article claims that Husserl’s conception of the noetic-noematic correlation does not lead to the correlativistic prejudice. Husserl distinguishes between two concepts of object: the noematic ‛object simpliciter’ (the pure X) and the ‛object in the How of its determinations’ (a noematic sense), and he demonstrates that the noematic ‛object simpliciter’ transcends the limit of actual noetic-noematic correlation, it is a correlate of the Idea in the Kantian sense of the term and this idea cannot be intrinsically given in its content. In the article the author shows that Husserl’s concept of the noematic ‘object simpliciter’ as a pure X is similar to Kant’s concept of transcendental object as ‛something in general = X’. In analogy to a transcendental object, noematic ‛object simpliciter’ is partially knowable and it appears to be an irrational fact in its unknowable rest. As a consequence, the ‛object simpliciter’ is something more than a correlate of consciousness and retains always its extra-noematic content. Therefore, the world is only partially correlative to the possibility of experience.
Bogusław Wolniewicz’s book Things and facts, although it is essentially devoted to the interpretation of the Wittgenstein’s Tractatus, also has a substantive layer in which Wolniewicz raises very important problems in the fields of methodology, semiotics and metaphysics, such as: (a) the problem of clarity of philosophical texts and its relation to simplicity and brevity, as well as to thoroughness and suggestiveness; (b) the problem of semantic correlation types; (c) the problem of analysis, interpretation and definition; (d) the problems of modality, negative facts, absolute monism and coherentionism; (e) the problem of abstraction and moral-praxeological antinomy. The author of the paper reconstructs Wolniewicz’s views on these matters.