Volume 114 (2017): Issue 9 (September 2017)

The region of the Saar Basin in Germany and Moselle in France used to be one of the most important centres of coal mining. Spatial transformations of the region are related to the close-down of collieries and to the redevelopment of the former mining facilities. The research carried out by the Author in 2015 enabled an analysis of mines, taking into account the mode and scope of their redevelopment, as well as significance of these facilities. Several types of transformations have been distinguished – ranging from demolition of the former mining facilities to their adaptation for a new use. The analysis has given grounds for an evaluation of the observed processes, also in the aspect of the significance of the mines for revitalisation of the degraded areas. The conclusions primarily refer to the mining facilities in the Saarland-Moselle region, yet they may provide a reference point in the evaluation of transformations of similar European regions.

Buildings can create a sense of community and add to the character of neighborhoods and cities. They can also support communities by either directly contributing to the infrastructure requirements of their neighbors, or by reducing their own demands and/or creating their own supply and treatment systems to create capacity for others in, for example, community energy and water systems. Buildings can also reduce wastage with its environmental and economic burdens by recapturing heat being lost through inefficient systems and by using municipal waste, especially bio-waste, as a fuel source. Building energy demands are a significant part of the challenge to reduce dependence on fossil fuels, save on resources, to cut emissions and mitigate the effects of climate change, while also representing opportunities to reduce the negative impacts on municipal infrastructure. This paper explains how buildings can mitigate such impacts while also acting as elements of infrastructure.

This paper summarises methods of scheduling construction processes with the use of artificial intelligence methods. Rules used for the calculation are characterised taking into account the implementation of priorities and resource constraints.

This paper describes the laboratory examination of the dynamic parameters of cohesive soil together with an analysis of these parameters using artificial intelligence. The analysis yielded the propagation velocity of shear wave V_s and the dynamic Kirchhoff modulus G obtained during the soil tests in the triaxial stress apparatus. The investigation was conducted using bender elements. The artificial neural networks trained on data obtained from the test were used for the further analysis.

This article presents basic ideas for flexible design in construction investments through the presentation of methods used for assessing the financial effectiveness of investments. The classification of these methods based on two main factors, time and risk, is shown. The authors propose an algorithm for the analysis of the economic efficiency of projects implemented in a flexible manner.

This paper presents average normalised acceleration response spectra calculated for mining induced seismic events which were recorded by twenty-one stations located in the area of Legnica-Glogow Copper District (LGCD). In this paper, 5.246 ground motion signals with peak ground acceleration (PGA) over 0.03 m/s² were analysed. The ground motions were caused by 1.886 mining events with M_L greater than 2 (energy > 10⁵J), which occurred from 2004 to 2015. The design response spectra were estimated based on average normalised acceleration response spectra. Further analysis of results shows that the shape and amplitude of response spectra are strongly dependent on the event magnitude, the epicentral distance and the location of the stations. The obtained response spectra could be used for computing seismic forces which have impact on buildings response to ground motions caused by mining events in LGCD.

Modern technologies, which may include unmanned aerial vehicles (UAV, Polish abbreviation BSL), potentially have a very wide range of applications. Research has been conducted on the possibility of using UAVs to control the execution of construction works by the authors of the article among other researchers. The technical parameters of the applied measurement instruments are of great significance. This paper presents a possibility for the optimal choice of unmanned aerial vehicles using the AHP method. The popularity of this method results not only from its effectiveness in solving complex decision problems, but also from its transparency and ease of application. The decision-making analysis adopts the criteria that are essential with regard to the supervision of construction works which they may support.

The aim of this paper is to indicate solutions which fulfil the conditions for laying concrete mix before it starts setting. Using models M/M/N/-/N, for organization I for the so-called delivery directly after unloading, with automatic transfer of information using the RFID system, and M/M/1/FIFO/N/F, for organisation II with transportation units working in closed cycle. Of example, organisation I, with RFID system is more advisable as it is characterised by a shorter waiting time on construction sites; and longer at the concrete-mixing plant. At the same time, it increases the efficiency of working units compared with organisation II which has self-regulating transportation units running in closed cycle.

The article presents an analysis of influence of the LEED certification process to achieve the passive house standard of the building. The purpose of LEED certification is to reduce building energy consumption, water consumption and to reduce building impact on the environment. The passive building is characterized by low energy demand of 15 kWh/(m²*year). Passive buildings are the result of introducing new ideas in the design process of buildings. This article presents the results of the analysis based on example objects. The results show that the LEED certification significantly influences the achievement of the passive building standard.

The aim of the paper is to prove two theorems on continuous dependence of mild solutions, on initial nonlocal data, of the nonlocal semilinear evolution Cauchy problems. For this purpose, the method of semigroups and the theory of cosine family in Banach spaces are applied. The paper is based on publications [1–6] and is a generalization of paper [3].

Tidal turbines are gaining more and more interest as a source of renewable energy. Energy from tidal currents may be extracted in a similar way as wind energy but tidal turbines have to meet much higher requirements. Cavitation phenomena, which are difficult to predict, have great influence on hydrodynamic efficiency. This paper presents the use of CFD simulation for prediction of cavitation during flow over typical NACA airfoils.

The paper presents an analysis of the usability of a selected web site using the QFD quality method. User requirements and related technical parameters used for creating diagrams of similarities and dependencies have been identified. Diagrams showing user and technical benchmarking as well as graphs of target values evaluated for user requirements and technical parameters were created.

This paper presents the homotopy perturbation method for solving linear and non–linear two–point boundary value problems in the form of a fourth–order differential equation and five boundary conditions. Three initial and two final conditions were taken into account. The solution of this problem is possible only when the considered equation includes an unknown parameter. The presented method has been illustrated with a numerical example.

The Earned Value Method (EVM) is a method commonly used in the quantitative project management. The course of the actual curve is usually different from the course of the planned curve. In order to provide a reliable estimation of the time of the project implementation or its real cost, the method of on-line updating the actual cost (AC) original curve can be applied. The actual cost curve is usually of the S-curve character. The approximation method is often used in the engineering applications. In the paper, the possibility of applying the polynomial type approximation method to the on-line updating of the actual cost curve is discussed.

The paper presents multi-thread calculations using parallel evolutionary algorithms (EA) for single and multicriteria design optimization. This approach was implemented to avoid a negative influence of incorrectly chosen initial and EA’s control parameters for the accuracy of generated solutions and thereby to improve the effectiveness of the EA’s use. Parallel computation for single optimization problems relies just on running n threads with different randomly chosen parameters in order to find the best final solution. For multicriteria optimization problems, each thread generates a set of Pareto optimal solutions and at the end these sets are combined together, giving a real set of Pareto optimal solutions. During the run of the algorithm, random interactions between threads were applied. The experiments were carried out using ten-thread processes for different examples of single and multicriteria design optimization problems, two of which are presented in the paper.

This article presents the results of pioneer experimental research into the impact of whole body vibration (WBV) and hand arm vibration (HAV) with different amplitudes and frequencies on percussive tools which are controlled by hand. In these studies the human operator is considered as the active element of the control system. The quality of control executed by the participants of the tests was assessed by the typical parameters existing in control system engineering, such as rise time, settling time, overshoot and integral square error (ISE). The tests were performed on an especially built stand. Results are presented in the form of time histories of step reference force. Forces realized by the operator were statistically analysed and graphically presented. Local (HAV) vibration of tools and accompanying dynamic forces between the handle and the vibrating tool have a big influence on control of the tool. An increase in the frequency of the tools’ vibration increases the adjustment range. The influence of platform vibrations on the adjustment range is relatively small.

The paper presents the optimization problem of a thread root undercut in the roller of planetary roller screw using FEM. The depth and shape of the undercut as well as the radii of thread profiles curvature were optimized for the series of cooperating threads. The maximum HMH reduced stress in the undercut was accepted as an objective function. The limitation to the maximum contact pressure was assumed. The procedure aimed at limiting the range of variables was accepted in order to improve the efficiency of optimization method.

Modeling a flow thorough a fluidized bed is a complicated, time-consuming and power-demanding task. However, in some cases such a flow could be simplified as a porous media flow, when we treat it as a fixed bed. This publication presents a comparison between free flow and porous media flow in order to assess the effect on the surface layer erosion.

The article presents a method used in the process of generating smart designs of experiment in a dedicated computer program with the application of pseudo-random numbers, the use of which may have a considerable impact on the quality of generated designs. In order to increase the probability of generating the optimal design for the defined parameters of generating, a special method was applied, in which several designs were generated and the best of them selected, based on the equipartitional analysis parameters. The results confirm a significant positive influence of the analyzed method on the smart design’s quality.