In case of the private procurement auctions the entrepreneurs are not forced to limit themselves to the standard auction rules, and in practice one can observe many hybrid or quasi-auction mechanisms spontaneously introduced. The paper analyzes two of them, which start as a first-price sealed-bid auction, followed by a run-off in a form of an English auction, and which differ by the transparency of rules concerning the initiation of the second stage. The focus of the paper is on the analysis of the price and allocative efficiency of these mechanisms, in order to determine whether they can serve as an alternative to the standard auction rules. Theoretical analyses are followed by the laboratory experiments, which demonstrate that the mechanisms under study are characterized by both high price and allocative efficiency, and therefore could be considered an interesting substitute of the standard auction rules.

Maximum score estimation is a class of semiparametric methods for the coefficients of regression models. Estimates are obtained by the maximization of the special function, called the score. In case of binary regression models it is the fraction of correctly classified observations. The aim of this article is to propose a modification to the score function. The modification allows to obtain smaller variances of estimators than the standard maximum score method without impacting other properties like consistency. The study consists of extensive Monte Carlo experiments.

The article presents the results of experimental investigations of interactions between a deformable structure and a liquid. The investigations were performed on two prismatic tanks with elastically deformable top walls. During the investigations, different levels of tank filling with liquid were examined. The investigation of this phenomenon has direct reference to frequently recorded real events, such as collision of a tanker with another ship or a harbour berth, rapid braking of a road or rail tanker, etc. Recognition of this phenomenon is based on simultaneous measurements of the following parameters:

1. excited accelerations of the tank-liquid system,

2. elastic accelerations of top walls of the tank,

3. hydrodynamic pressures on the deformable top walls.

The objective of the study was to compare the impact of three systems of multiannual fertilization applied in two long-term field experiments on the content of phenolic compounds in the soil. In the study, both natural (manure, slurry) and mineral (NPK) fertilizers were used, along with combined, organic-and-mineral fertilization. Experiment I was established in 1972 on grey brown podzolic soil; experiment II, in 1973 on brown soil. In both experiments crops were cultivated in a 7-year rotation, with a 75% share of cereals. The experimental samples were taken from the top layer of soil after 36 (experiment I) and 35 (experiment II) years following the establishment of the experiments. It was demonstrated that the presence of phenolic compounds in the soils was significantly dependent on the contents of organic C and total N, type of soil and the type and dose of used fertilizers. In grey brown podzolic soil, the content of total phenolic compounds was at a lower level than the content found in brown soil. Multiannual fertilization contributed to an increase in the content of total phenolic compounds in relation to the values obtained in control objects, which was particularly reflected in the soil originating from objects fertilized with slurry applied at a dose being equivalent to manure in terms of the amount of introduced organic carbon. The percentage of water-soluble phenols in the total content of these compounds in grey brown podzolic soil was at the level of 18.4%, while in brown soil it amounted to 29.1%.

Experiments of filling the model moulds cavity of various inner shapes inserted in rectangular cavity of the casting die (dimensions: 280

mm (height) x 190 mm (width) x 10 mm (depth) by applying model liquids of various density and viscosity are presented in the paper.

Influence of die venting as well as inlet system area and inlet velocity on the volumetric rate of filling of the model liquid – achieved by

means of filming the process in the system of a cold-chamber casting die was tested. Experiments compared with the results of simulation

performed by means of the calculation module Novacast (Novaflow&Solid) for the selected various casting conditions – are also

presented in the paper.

The topic of incompressible fluid flow in rough channels is of practical interest in many diverse applications. It also forms the basis of our understanding of fluid-wall interactions, turbulent eddy generation, and their effect on the frictional pressure losses. Although this topic is also of fundamental interest, the work in this area is entirely guided by the experimental work of earlier investigators [1–6]. The works by Nikuradse [4] and Colebrook [5] constitute a major milestone from which useful empirical models are derived. As we approach the microscale, Nikuradse’s experimental work again is brought to focus, perhaps this time to gain an insight into the mechanisms affecting fluid-wall interaction in rough channels. In this paper, Nikuradse’s work is revisited in light of the recent experimental work on roughness effects in microscale flow geometries.

The paper presents the methodology that makes it possible to evaluate computational model and introduce current corrections to it. The methodology ensures proper interpretation of nonlinear results of numerical analyses of thin-walled structures. The suggested methodology is based on carrying out, in parallel to nonlinear numerical analysis, experimental research on some selected crucial zones of loadcarrying structures. Attention is drawn to the determinants concerning the performance of an adequate experiment. The author points out on indicating the role of model tests as a fast and economically justified research instruments practicable when designing thin-walled load-carrying structures.

The presented considerations are illustrated by an example of a structure whose geometrical complexity and ranges of deformation are characteristic for modern solutions applied in the load-carrying structures of airframes. As the representative example, one selected the area of the load-carrying structure that contains an extensive cut-out, in which the highest levels and stress gradients occur in the conditions of torsion evoking the post-buckling states within the permissible loads. The stress distributions within these ranges of deformations were used as the basis for determining the fatigue life of the structure.

Flexible, slender structures like cables, hoses or wires can be described by the geometrically exact Cosserat rod theory. Due to their complex multilayer structure, consisting of various materials, viscoplastic behavior has to be expected for cables under load. Classical experiments like uniaxial tension, torsion or three-point bending already show that the behavior of e.g. electric cables is viscoplastic. A suitable constitutive law for the observed load case is crucial for a realistic simulation of the deformation of a component. Consequently, this contribution aims at a viscoplastic constitutive law formulated in the terms of sectional quantities of Cosserat rods. Since the loading of cables in applications is in most cases not represented by these mostly uniaxial classical experiments, but rather multiaxial, new experiments for cables have to be designed. They have to illustrate viscoplastic effects, enable access to (viscoplastic) material parameters and account for coupling effects between different deformation modes. This work focuses on the design of such experiments.

Consumer experiences as a driver of contemporary brand and marketing management are taken up nowadays by many researchers and academics. It’s merely compelled by bored with generic products and services consumers who much more than ever look for intensive, personalized experiences. However, there is a significant gap in knowledge how to transfer these global changes to the needs of effective tourist product management. The article presents a brand-new approach called ‘the experience key’ for discovering, grouping and converting common, dedicated to a certain destination customers experiences into clear and desirable tourist offer with meaningful competitive impact. One of most important advantages of the methodology is its simplicity and ease-of-use for any professionals involved in destination product management by using well-know research methods and apparent applicability into the process of building and selling tourist offer of a place. The Experience Key can be regarded as a missing link between theoretical considerations led by academics and expectations of tourism industry representatives in the context of applying customer experience to place brand and product management.

There is a growing body of research investigating the relationships among gratitude, self-esteem, and subjective well-being. However, there remains a scarcity of research examining the impact of self-esteem on the relationship between gratitude and subjective well-being within Arabic context. In this study, 300 Arabic speaking adults completed measurements of gratitude, self-esteem, satisfaction with life, and positive and negative experiences. Participants’ ages ranged between 18 and 54 years with a mean age of 29.67 years (SD = 8.91). The correlation results revealed that there were significant positive relationships between gratitude, self-esteem, satisfaction with life, and positive experience, while there were significant negative relationships between gratitude, self-esteem, satisfaction with life, and negative experience. The results also showed that gratitude and self-esteem directly predicted subjective well-being. Additionally, using structural equation modeling, self-esteem exerted a mediation effect on the relationship between gratitude and subjective well-being. The results suggest that enhancing self-esteem could assist adults who have gratitude to experience greater subjective well-being. Using the source of self-esteem, researchers and professionals could improve one’s subjective wellbeing by employing various gratitude activities.

This work attempts to reconstruct the culture that contributed to the philosophical way of thinking. My goal is to extract two important factors: religion carrying individual experience and the importance of certain ideas which are present in that culture. Sources of philosophical thinking can be found in the structure of polis. Only on its basis could the idea of the wise man and citizen as well as religion-oriented individual experience be raised. Greek polis paves the way for a new style of thinking by creating the conditions for its citizens to follow the ideal, regardless of the position they occupy in society. Sustainability, which should be a feature of a good citizen, is also the essence of society. Highly positioned wisdom as moral reflection tinged with religiosity allows thinking according to the laws of logos. Finally, the experience offered by the mystery cults leads to the transformation of their own existence and the emergence of a way of recognition of reality different than before. Undeniably, all the elements related to structure policies with its ideals contribute to the emergence of a new way of thinking in the form of philosophy. One could say that the philosophical objectivity is preceded by the subjectivity and rationality of its roots dating back to irrationality.

The article presents scientific achievements of Alfred Nobel Memorial Prize Laureates in economic sciences in 2019: Esther Duflo, Abhijit Banerjee, and Michael Kremer. The paper describes their contribution to the research on the sources of poverty in the world and the ways of alleviating it, and their contribution to the development of experimental research in social sciences using randomized control trials (RCT). In this context, the authors explain the reasons for growing popularity of this approach in development economics and discuss its strengths and weaknesses.