The collapse of the Soviet Union was the cause of a significant decline in many economies of the newly created countries. However, many of them, including the Ukrainian economy, are slowly recovering. One of the largest branches of the economy in this country is construction, which, despite political turmoil, is constantly growing, especially in the private real estate development sector. Despite the fact that the construction market is constantly developing, it is limited by the costs of rework and alterations resulting from many reasons. The key negative effects of modifications to the results of the project are exceeding the budget and time of project implementation, dissatisfaction with the project team, violation of contractual requirements and lowering the quality of the final product. Therefore, the purpose of this article was to determine the reasons for the emergence of rework in the in Ukraine by analyzing the results of surveys conducted among construction enterprises.

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During the planning and controlling of the construction process, most attention is focused 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.

Various human activities have been the main causes of surface water pollution. The uneven distribution of industrial enterprises in the territories of the main river basins of Ukraine do not always allow the real state of the water quality to be assessed. This article has three purposes: (1) the modification of the Ukrainian method for assessing the WQI, taking into account the level of negative impact of the most dangerous chemical elements, (2) the modeling of WQI assessment using fuzzy logic and (3) the creation of an artificial neural network model for the prediction of the WQI. The fuzzy logic model used four input variables and calculated one output variable (WQI). In the final stage of the study, six ANN models were analyzed, which differed from each other in various loss function optimizers and activation functions. The optimal results were shown using an ANN with the softmax activation function and Adam’s loss function optimizer (MAPE = 9.6%; R2 = 0.964). A comparison of the MAPE and R2 indicators of the created ANN model with other models for assessing water quality showed that the level of agreement between the forecast and target data is satisfactory. The novelty of this study is in the proposal to modify the WQI assessment methodology which is used in Ukraine. At the same time, the phased and joint use of mathematical tools such as the fuzzy logic method and the ANN allow one to effectively evaluate and predict WQI values, respectively.

The aim of the article is to develop an assessment model for the effect received from the integration of enterprises during the realization of investment projects in the construction. Having analysed the existing methods of the economic effect evaluation, we came to the conclusion that it is impossible to use them completely to assess the economic effect of the integration of enterprises during the investment projects in the construction. In the case of an integrated realization of a project in the construction sector, it is the information and communication links that are combined, and not the enterprises themselves. In addition to that, not all models take into account the synergistic effect. To solve the above-mentioned problem, we analysed the advantages gained by participants during the realization of the integrated project in construction and the benefits that have the greatest impact on the synergy effect. The calculation of the effect of the information and communication system management and the innovative nature of the process of its implementation suggest that this process has a clear investment component. Consequently, the process of enterprise integration should be considered as an investment project implemented at the level of network association.