New examples of K-monotone weighted Banach couples

Some new examples of K-monotone couples of the type (X, X(w)), where X is a symmetric space on [0, 1] and w is a weight on [0, 1], are presented. Based on the property of the w-decomposability of a symmetric space we show that, if a weight w changes sufficiently fast, all symmetric spaces X with non-trivial Boyd indices such that the Banach couple (X, X(w)) is K-monotone belong to the class of ultrasymmetric Orlicz spaces. If, in addition, the fundamental function of X is t^{1/p} for some p \in [1, \infty], then X = L_p. At the same time a Banach couple (X, X(w)) may be K-monotone for some non-trivial w in the case when X is not ultrasymmetric. In each of the cases where X is a Lorentz, Marcinkiewicz or Orlicz space we have found conditions which guarantee that (X, X(w)) is K-monotone.Comment: 31 page

Stability of Biaxial Nematic Phase for Systems with Variable Molecular Shape Anisotropy

We study the influence of fluctuations in molecular shape on the stability of the biaxial nematic phase by generalizing the mean field model of Mulder and Ruijgrok [Physica A {\bf 113}, 145 (1982)]. We limit ourselves to the case when the molecular shape anisotropy, represented by the alignment tensor, is a random variable of an annealed type. A prototype of such behavior can be found in lyotropic systems - a mixture of potassium laurate, 1-decanol, and $D_2O$, where distribution of the micellar shape adjusts to actual equilibrium conditions. Further examples of materials with the biaxial nematic phase, where molecular shape is subject to fluctuations, are thermotropic materials composed of flexible trimeric- or tetrapod-like molecular units. Our calculations show that the Gaussian equilibrium distribution of the variables describing molecular shape (dispersion force) anisotropy gives rise to new classes of the phase diagrams, absent in the original model. Depending on properties of the shape fluctuations, the stability of the biaxial nematic phase can be either enhanced or depressed, relative to the uniaxial nematic phases. In the former case the splitting of the Landau point into two triple points with a direct phase transition line from isotropic to biaxial phase is observed.Comment: 18 pages containing 6 figure

AmbieSense: a system and reference architecture for personalised and context-sensitive information services for mobile users

The purpose of AmbieSense is to provide personalised, context-sensitive information to the mobile user. It is about augmenting digital information to physical objects, rooms, and areas. The aim is to provide relevant information to the right user and situation. Digital content is distributed from the surroundings and onto your mobile phone. An ambient information environment is provided by a combination of context tag technology, a software platform to manage and deliver the information, and personal computing devices to which the information is served. This paper describes how the AmbieSense reference architecture has been defined and used in order to deliver information to the mobile citizen at the right time, place and situation. Information is provided via specialist content providers. The application area addresses the information needs of travellers and tourists

Ways residents of large cities in Poland, commute before and during the Covid-19 pandemic

PURPOSE: The article concerns the issues related to the methods of movement of people in urban areas by means of cars, trams, buses, bicycles, e-scooters, electric scooters and on foot. Its purpose is to present selected factors determining this choice.DESIGN/METHODOLOGY/APPROACH: The authors, using the proprietary questionnaire, conducted a survey among the inhabitants of one of the largest cities in Poland - Szczecin to determine their current preferences related to the way of movement before and during the pandemic caused by the Covid-19 virus. Non-parametric dual and multiple comparison tests, the Mann-Whitney U test and the Kruskal-Wallis rank ANOVA were performed. The Cronbach's α coefficient was used to assess the reliability of the measuring scale.FINDINGS: The conducted analyzes allowed to determine the most common ways of traveling, the level of their safety and accessibility for residents. Statistically significant differences were found in respondents' opinions, depending on age, gender, industry, and education. The impact of the Covid-19 pandemic on opinions on the frequency of use, safety, and availability of means of transport in Szczecin was verified. The analysis showed a slight decrease in the declared frequency of using the analyzed means of transport and no decrease in the safety assessment of the analyzed means of transport during the application of the restrictions related to Covid-19.PRACTICAL IMPLICATIONS: The presented analysis and assessment of the ways in which the inhabitants of Szczecin move could be used in rational actions of the local authorities aimed at improving the quality of life of the inhabitants and friendly to the inhabitants of the city in the context of public and individual transport.ORIGINALITY/VALUE: The authors compared the preferences of the ways of movement and the implemented solutions with the parameters of their effectiveness, based on the experimental results and foreign literature.peer-reviewe

Identification of threats in the supply chain of a production process

PURPOSE: Economic growth, along with aggressive competition, directly influences the functioning of supply chains and equally shapes all internal and external threats. This publication aims to present the identification process and analyse the significance of threats in supply chains at the stage of the production process of structural elements.DESIGN/METHODOLOGY/APPROACH: An appropriate questionnaire and checklist have been developed to determine the frequency of threats. The analysis of measurement scale reliability was performed using the α-Cronbach coefficient and Guttman split-half method. Finally, the research results were analysed using the proprietary ranking method based on the adopted measurement scale.FINDINGS: The empirical results indicate that the survey conducted using the adopted questionnaire and the checklist allows for identifying threats in the supply chains occurring in the manufacturing process. In contrast, the frequencies of threat occurrence determined using a survey questionnaire allow for appropriate ranking.PRACTICAL IMPLICATIONS: The study should be treated as a pilot for a group of medium-sized manufacturing companies implementing a sustainable development policy.ORIGINALITY/VALUE: Threat assessment in production processes and supply chains can have a practical impact on shaping enterprises' policy of sustainable development.peer-reviewe

A Hybrid Neural Network for Graph-Based Human Pose Estimation from 2D Images

© 2013 IEEE. This paper investigates the problem of human pose estimation (HPE) from single 2-dimensional (2D) still images using a convolutional neural network (CNN). The aim was to train the CNN to analyze a 2D input image of a person to determine the person's pose. The CNN output was given in the form of a tree-structured graph of interconnected nodes representing 2D image coordinates of the person's body joints. A new data-driven tree-based model for HPE was validated and compared to the traditional anatomy-based tree-based structures. The effect of the number of nodes in anatomy-based tree-based structures on the accuracy of HPE was examined. The tree-based techniques were compared with non-tree-based methods using a common HPE framework and a benchmark dataset. As a result of this investigation, a new hybrid two-stage approach to the HPE estimation was proposed. In the first stage, a non-tree-based network was used to generate approximate results that were then passed for further refinement to the second, tree-based stage. Experimental results showed that both of the proposed methods, the data-driven tree-based model (TD_26) and the hybrid model (H_26_2B) lead to very similar results, obtaining 1% higher HPE accuracy compared to the benchmark anatomy-based model (TA_26) and 3% higher accuracy compared to the non-tree-based benchmark (NT_26_A). The best overall HPE results were obtained using the anatomy-based benchmark with the number of nodes increased from 26 to 50, which also significantly increased the computational cost

Roundoff-induced Coalescence of Chaotic Trajectories

Numerical experiments recently discussed in the literature show that identical nonlinear chaotic systems linked by a common noise term (or signal) may synchronize after a finite time. We study the process of synchronization as function of precision of calculations. Two generic behaviors of the average coalescence time are identified: exponential or linear. In both cases no synchronization occurs if iterations are done with {\em infinite} precision.Comment: 6 pages, 3 postscript figures, to be published in Phys. Rev.

Level Eulerian Posets

The notion of level posets is introduced. This class of infinite posets has the property that between every two adjacent ranks the same bipartite graph occurs. When the adjacency matrix is indecomposable, we determine the length of the longest interval one needs to check to verify Eulerianness. Furthermore, we show that every level Eulerian poset associated to an indecomposable matrix has even order. A condition for verifying shellability is introduced and is automated using the algebra of walks. Applying the Skolem--Mahler--Lech theorem, the ${\bf ab}$-series of a level poset is shown to be a rational generating function in the non-commutative variables ${\bf a}$ and ${\bf b}$. In the case the poset is also Eulerian, the analogous result holds for the ${\bf cd}$-series. Using coalgebraic techniques a method is developed to recognize the ${\bf cd}$-series matrix of a level Eulerian poset