bluuebunny/crossref_metadata_2025_split huggingface dataset:
Location-Optimized Aerodynamic Rotor Design of Small Wind Turbines and Lightweight Implementation Using Additive Hybrid Material
Authors: Lehser-Pfeffermann Daniel , Häfele Tobias , Rückert Frank U. , Griebsch Jürgen , Müller Tobias , Joos Franz 
Published: August 2020

Abstract
Wind power plays a crucial role in supplying cities with renewable energy. Combined with short transport routes, it is essential to establish site-specific small wind turbines in the urban environment. An increasing interest in small, decentralized, vertical-axis wind turbines (VAWT) can be observed here. However, concepts with low visual and auditory effects and economic efficiencies are largely limited. The project part described in this paper enables a specially developed design software tool of rotor geometries optimized for such boundary conditions. By using fiber-reinforced structures in combination with selective laser sintering, it is theoretically possible to economically produce even the smallest quantities of these geometries for a typical service life of wind turbines. The results presented and discussed in this work can serve as a basis for a subsequent feasibility study.
Numerical and Experimental Investigation of the Fan with Cycloidal Rotor
Authors: Dykas Sławomir , Majkut Mirosław , Smołka Krystian , Strozik Michał , Chmielniak Tadeusz , Staśko Tomasz 
Published: August 2020

Abstract
In this paper, the investigation of the cycloidal rotor fan (CRF) was presented. A CRF with four blades of the NACA0012 profile was used for the analysis. The CFD calculations were carried out by means of Ansys CFX commercial software. The experimental tests were done using velocity field measurement with the LDA technique. Numerical results were compared with experimental measurement in terms of velocity values. The CRF performance characteristic was prepared on the basis of experimental and numerical results.
Advances and Breakthroughs in Diffusers for Compressors and Pumps: A Short History of Diffusers for Centrifugal Machines
Authors: Japikse David 
Published: August 2020

Abstract
The diffuser plays an indispensable role in setting the useable flow range and efficiency for centrifugal machinery. Key aspects of the history and design of such diffusers are overviewed followed by a look at current, novel ideas for better systems. Improved machinery can be expected in the coming years due to decades of development work in this field.
Influence of the Diffuser on the Drag Coefficient of a Solar Car
Authors: Mierzejewska Paula , Cieśliński Artur , Jodko Daniel 
Published: August 2020

Abstract
The purpose of the research was to design a solar vehicle for Bridgestone World Solar Challenge competition which takes place biannually in Australia. The article, however, presents the aerodynamic research on the car body, especially on the exit diffuser. Numerous CFD simulations of different diffuser shapes were performed in ANSYS CFX software. The paper presents the results of pressure distribution on the body and velocity contours. The drag force acting on the car body is dependent on the pressure distribution. The article includes comparison of corresponding drag coefficient values for different cases. Furthermore, the variation of the lift force depending on the shape of the bodywork was also taken into consideration. The research shows that slight differences in the construction of the exit diffuser correspond to noticeable changes in the drag coefficient values (0.138 minimum, 0.168 maximum) and significant changes in the lift force (minimum 71 N, maximum 160 N).
Design and Manufacturing of Micro-Turbomachinery Components with Application of Heat Resistant Plastics
Authors: Żywica Grzegorz , Kaczmarczyk Tomasz , Ihnatowicz Eugeniusz , Bagiński Paweł , Andrearczyk Artur 
Published: August 2020

Abstract
The article discusses issues associated with the use of modern plastics for the construction of high-speed fluid-flow machines. Currently available plastics exhibit high chemical resistance as well as dimensional and shape stability across a wide temperature range. This allows them to be used for manufacturing components of micro turbomachinery, thereby reducing production time and costs. This article discusses the criteria for the selection of plastics suitable for a particular machine, namely micro turbogenerator operating in the organic Rankine cycle (ORC). In addition to the initial selection of materials based on their chemical and physical properties, strength calculations of selected turbogenerator subassemblies were carried out. The obtained results confirmed that some plastics can replace traditional materials used in the manufacture of ORC turbogenerators. This concerns, in particular, the components of the microturbine blade system. After the manufacture of a trial series of such components, it became apparent that, with appropriately chosen plastics, it is possible to shorten the machining time and reduce production costs, all while maintaining the required dimensional tolerances. The results obtained so far prove that it is possible to use plastics to produce components of modern turbomachines, for instance, parts of high-speed microturbines that have to withstand high operating temperatures.
An Interface Anticrack in a Periodic Two–Layer Piezoelectric Space under Vertically Uniform Heat Flow
Authors: Kaczyński Andrzej , Kaczyński Bartosz 
Published: August 2020

Abstract
This paper aims to investigate 3D static thermoelectroelastic problem of a uniform heat flow in a bi-material periodically layered space disturbed by a thermally and electrically-insulated rigid sheet-like inclusion (so-called anticrack) situated at one of the interfaces. An approximate analysis of the considered laminated composite is given in the framework of the homogenized model with microlocal parameters. Accurate results are obtained by constructing suitable potential solutions and reducing to the corresponding homogeneous thermoelectromechanical (or thermomechanical) anticrack problems. The governing boundary integral equation for a planar interface anticrack of arbitrary shape is derived in terms of a normal stress discontinuity. As an illustration, a complete solution for a rigid circular inclusion is obtained in terms of elementary functions and interpreted from the failure perspective. Unlike existing solutions for defects at the interface of materials, the solution obtained displays no oscillatory behavior.
Fourier Variant Homogenization Treatment of Single Impulse Boundary Effect Behaviour
Authors: Kula Dorota , Wierzbicki Ewaryst , Witkowska-Dobrev Joanna , Wodzyński Łukasz 
Published: August 2020

Abstract
Boundary effect behavior understood as near-boundary suppression of boundary fluctuation loads is described in various ways depending on the mathematical representation of solutions and the type of the center. In the case of periodic composites, the homogenization method is decisive here. In the framework of the Tolerance Averaging Approach, developed by prof. Cz. Woźniak leading to an approximate model of phenomena related to periodic composites this effect is described by a homogeneous part of differential equation for fluctuation amplitudes and usually this approximate description of the boundary effect behavior is restricted to a single fluctuation. In this paper, contrary to the previous elaborations, the boundary effect is developed in the variant of the tolerance thermal conductivity model in which the temperature field is represented by the Fourier expansions composed by an average temperature with infinite number of Fourier terms imposed on the average temperature as tolerance fluctuation suppressed in the framework of the boundary effect.
Asymptotic Behavior of Magnetostrictive Elasticity for Microstructured Materials
Authors: Bojarski Jarosław L. , Wierzbicki Ewaryst 
Published: August 2020

Abstract
According to the classical theory of Weiss, Landau, and Lifshitz, in a ferromagnetic body there is a spontaneous magnetization field m, such that ∥m∥ = τ
0 = const in all points of this material Ω. In any stationary configuration, this ferromagnetic body consists of areas (Weiss domains) in which the magnetization is uniform (i.e. m = const) separated by thin transition layers (Bloch walls). Such stationary configuration corresponds to the minimum point of the magnetostrictive free energy E. We are considering an elastic magnetostrictive body in our paper. The elastic magnetostrictive free energy Eδ
depends on a small parameter δ such that δ → 0. As usual, the displacement field is denoted by u. We will show that each sequence of minimizers (ui, mi
) contains a subsequence that converges to a couple of fields (u
0, m
0). By means of a Γ-limit procedure we will show that this couple (u
0, m
0) is a minimizer of the new functional E
0. This new functional E
0 describes the magnetic-elastic properties of the body with microstructure.
Micro-Vibrations and Wave Propagation in Biperiodic Cylindrical Shells
Authors: Tomczyk Barbara , Litawska Anna 
Published: August 2020

Abstract
The objects of consideration are thin linearly elastic Kirchhoff-Love-type circular cylindrical shells having a periodically microheterogeneous structure in circumferential and axial directions (biperiodic shells). The aim of this contribution is to study a certain long wave propagation problem related to micro-fluctuations of displacement field caused by a periodic structure of the shells. This micro-dynamic problem will be analysed in the framework of a certain mathematical averaged model derived by means of the combined modelling procedure. The combined modelling applied here includes two techniques: the asymptotic modelling procedure and a certain extended version of the known tolerance non-asymptotic modelling technique based on a new notion of weakly slowly-varying function. Both these procedures are conjugated with themselves under special conditions. Contrary to the starting exact shell equations with highly oscillating, non-continuous and periodic coefficients, governing equations of the averaged combined model have constant coefficients depending also on a cell size. It will be shown that the micro-periodic heterogeneity of the shells leads to exponential micro-vibrations and to exponential waves as well as to dispersion effects, which cannot be analysed in the framework of the asymptotic models commonly used for investigations of vibrations and wave propagation in the periodic structures.
An Evaluation of On-Tool System for Sanding Dust Collection: Pilot Study
Authors: Dado Miroslav , Lamperová Anna , Kotek Luboš , Hnilica Richard 
Published: August 2020

Abstract
Hazards identification is essential step in framework of occupational health & safety (OH&S) management system. The task of spruce wood sanding with hand-held power belt sander is considered as a significant resource of exposure to wood dust. Dust from spruce wood is hazard that can cause negative health effects such as asthma and chronic bronchitis. A dust collection box is a commonly used technical measure for reducing exposure to wood dust for this task in practice. The objective of this pilot study was to evaluate the effectiveness of commercially available dust collection box at reducing exposure to wood dust during the task of sanding spruce wood using hand-held power belt sander. Laboratory experiment involved sanding spruce planks (250 mm × 50 mm × 500 mm) in longitudinal direction using belt sander (Bosch, PBS 75 A) with 120 grit sanding belt. Spruce dust mass concentrations were sampled using an aerosol monitor (TSI Inc., DustTrak DRX 8533) in the breathing zone of operator. Inhalable and respirable dust concentrations were both significantly lower (P < 0.0001) when dust box was attached to belt sander compared with sander without a dust box. Results from this pilot study indicate that dust collection box is efficient technical measure for decreasing exposure to aerosol mass concentration during sanding spruce wood with hand-held belt sander.
Summer–winter contrast in carbon isotope and elemental composition of total suspended particulate matter in the urban atmosphere of Krakow, Southern Poland
Authors: Zimnoch Miroslaw , Morawski Filip , Kuc Tadeusz , Samek Lucyna , Bartyzel Jakub , Gorczyca Zbigniew , Skiba Alicja , Rozanski Kazimierz 
Published: August 2020

Abstract
The city of Krakow located in southern Poland ranks among the most polluted urban agglomerations in Europe. There are persisting controversies with respect to impact of different pollution sources operating in Krakow agglomeration on air quality within the city. The presented pilot study was aimed at exploring the possibilities offered by elemental and carbon isotope composition of total suspended particulate matter (TSPM) for better characterization of its sources in Krakow atmosphere. The analyses of carbon isotope composition of total carbon in the investigated TSPM samples were supplemented by parallel analyses of radiocarbon content in atmospheric carbon dioxide (CO2). This study revealed large seasonal variability of carbon isotope composition in the analysed TSPM samples. This large variability reflects seasonally varying contribution of different sources of fossil and modern carbon to the TSPM pool. The elemental composition of TSPM also reveals distinct seasonal variability of the analysed elements, reflecting varying mixture of natural and anthropogenic sources of those elements. A linear relationship between the fossil carbon load in the TSPM samples and the fossil carbon load in the atmospheric CO2 was found, pointing to the presence of additional source of anthropogenic carbonaceous particles not associated with burning of fossil fuels. Wearing of tyres and asphalt pavement is most probably the main source of such particles.
Tandem: Securing Keys by Using a Central Server While Preserving Privacy
Authors: Lueks Wouter , Hampiholi Brinda , Alpár Greg , Troncoso Carmela 
Published: August 2020

AbstractUsers’ devices, e.g., smartphones or laptops, are typically incapable of securely storing and processing cryptographic keys.We present Tandem, a novel set of protocols for securing cryptographic keys with support from a central server. Tandemusesone-time-use key-share tokensto preserve users’ privacy with respect to a malicious central server. Additionally, Tandemenables users to block their keys if they lose their device, and it enables the server to limit how often an adversary can use an unblocked key. We prove Tandem’s security and privacy properties, apply Tandemto attributebased credentials, and implement a Tandemproof of concept to show that it causes little overhead.
Automatic Discovery of Privacy–Utility Pareto Fronts
Authors: Avent Brendan , González Javier , Diethe Tom , Paleyes Andrei , Balle Borja 
Published: August 2020

Abstract
Differential privacy is a mathematical framework for privacy-preserving data analysis. Changing the hyperparameters of a differentially private algorithm allows one to trade off privacy and utility in a principled way. Quantifying this trade-off in advance is essential to decision-makers tasked with deciding how much privacy can be provided in a particular application while maintaining acceptable utility. Analytical utility guarantees offer a rigorous tool to reason about this tradeoff, but are generally only available for relatively simple problems. For more complex tasks, such as training neural networks under differential privacy, the utility achieved by a given algorithm can only be measured empirically. This paper presents a Bayesian optimization methodology for efficiently characterizing the privacy– utility trade-off of any differentially private algorithm using only empirical measurements of its utility. The versatility of our method is illustrated on a number of machine learning tasks involving multiple models, optimizers, and datasets.
PriFi: Low-Latency Anonymity for Organizational Networks
Authors: Barman Ludovic , Dacosta Italo , Zamani Mahdi , Zhai Ennan , Pyrgelis Apostolos , Ford Bryan , Feigenbaum Joan , Hubaux Jean-Pierre 
Published: August 2020

AbstractOrganizational networks are vulnerable to trafficanalysis attacks that enable adversaries to infer sensitive information fromnetwork traffic—even if encryption is used. Typical anonymous communication networks are tailored to the Internet and are poorly suited for organizational networks.We present PriFi, an anonymous communication protocol for LANs, which protects users against eavesdroppers and provides high-performance traffic-analysis resistance. PriFi builds onDining Cryptographers networks (DC-nets), but reduces the high communication latency of prior designs via a new client/relay/server architecture, in which a client’s packets remain on their usual network path without additional hops, and in which a set of remote servers assist the anonymization process without adding latency. PriFi also solves the challenge of equivocation attacks, which are not addressed by related work, by encrypting traffic based on communication history. Our evaluation shows that PriFi introduces modest latency overhead (≈ 100ms for 100 clients) and is compatible with delay-sensitive applications such as Voice-over-IP.
Privacy Preserving Detection of Path Bias Attacks in Tor
Authors: Watson Lauren , Mediratta Anupam , Elahi Tariq , Sarkar Rik 
Published: August 2020

Abstract
Anonymous communication networks like Tor are vulnerable to attackers that control entry and exit nodes. Such attackers can compromise the essential anonymity and privacy properties of the network. In this paper, we consider the path bias attack– where the attacker induces a client to use compromised nodes and thus links the client to their destination. We describe an efficient scheme that detects such attacks in Tor by collecting routing telemetry data from nodes in the network. The data collection is differentially private and thus does not reveal behaviour of individual users even to nodes within the network. We show provable bounds for the sample complexity of the scheme and describe methods to make it resilient to introduction of false data by the attacker to subvert the detection process. Simulations based on real configurations of the Tor network show that the method works accurately in practice.
Lung function testing assessment by impulse oscillometry in chronic lung disease
Authors: Cîrjaliu Roxana Elena , Arghir Ioan Anton , Beitula Enis , Odagiu Ionel , Ion Ileana , Nicolae Maria , Danteș Elena , Arghir Oana Cristina 
Published: August 2020

Abstract
Impulse oscillometry (IOS) is a variant of forced oscillation technique described by Dubois 50 years ago, which allows us to measure the reactance of the airways and the resistance of the small and large airways during tidal breathing. It requires minimal patient cooperation from subjects who are unable to perform spirometry, like elders, children and patients with neurologic disorders. IOS can outline the diagnosis of obstructive airway disease, differentiate small airway obstruction from large airway obstruction. It is more sensitive than spirometry for peripheral airway disease in determining the severity of the disease, the exacerbations and evaluate the therapeutic response. Other applications include early evaluation of transplant rejection, cystic fibrosis, vocal cord disorder, bronchiectasis, hypersensitivity pneumonitis, obstructive sleep apnea.
The Secret of Our Own Mortality
Authors: Dobrescu Georgiana 
Published: August 2020

Abstract
In this paper, the author tries to underline some aspects about one of the most important secrets: the secret of our own mortality. It is a paradox, all of us know that we will eventually die, but this knowledge is quite unbearable and makes us anxious, which is why it is very difficult for us to represent our death.
This secret of mortality is related to what Freud called “the biological rock” – our supreme and ultimate limit! – which represents the constitutional, biological dimension of the human being in its uniqueness and the way in which our psyche manages this reality, impossible to change.
The first part of paper is an exploration in the nature of secrets, healthy and pathogenic ones, known or unknown, conscious and unconscious. There are secrets which represent the intimate core of every person, what Winnicott called “an incommunicado element”. This is very precious, secret and sacred, and allows us to maintain a constant creative dialogue with ourselves and others while also ensuring our psychic sanity. There are also other secrets, pathogenic ones, which we encounter in the perverse, narcissistic structures and that disturb the relations with others.
There is a third category of secrets which we call ‘The secrets of Polichinelle’. They are like taboo subjects, as nobody touches them, but everybody knows them. In this category we find all the secrets connected to sexuality and, as a normal extension of them, the secrets linked to our own mortality.
In the second part of the paper, the author presents some vignettes from a case, which illustrate the theme of loss and the difficulty in accepting the limits set by the biological rock.
The Couple Object
Authors: Roussillon R. 
Published: August 2020

Abstract
The author argues for a conception of the oedipal complex that excludes the idea of a pre-oedipal phase which, according to him, comes from a confusion with the pre-genital. The author seeks to identify the existence of a “couple object” present early on in the young child whose pre-history he returns to in the first lineaments of a form of “being with”, as in the first form of recording relational models concerning the meeting with the first objects. This matrix will then be made more complex over time and brought into crisis in the “oedipal crisis”, and the way in which the child will be able to meet and go through this crisis, to organize himself and to organize the solutions to the crisis, will configure its model of “oedipal organization”.
Midlife: When the Body Challenges Time
Authors: de Vogelfanger Liliana Singman 
Published: August 2020

Abstract
This paper considers what occurs during midlife when the certainty-uncertainty tension that inhabits every subject is affected. The body with its drives becomes the messenger who announces the passage of time and life’s finitude. Time is challenged by one’s own body, triggering a psychic work that will enable the subject to deal with his/her own transience. Based on Freud’s writings, the author suggests that one’s own body is experienced as an annoying intruder that now bothers, because what is being touched is the idea of his/her own immortality. The emotional state that is generated is one of perplexity and the experience, one of disorientation, accompanied by a feeling of alienation. Each subject’s uniqueness will give him/her (or not) the possibility of passing from a feeling of alienation to the re-appropriation of that foreign-familiar zone. Due to the psychic impact generated, a change of paradigm is also put forward, if the necessary resources are available. Once the limitations of personal time and the uncertainty of living are recognized, the opening up of what-is-to-come can paradoxically take place, enabling the re-launching of one’s own desire.
Encounter with Death (I)
Authors: Popescu Alice 
Published: August 2020

Abstract
The article focuses on psychic mechanisms at work in a life experience of maximum intensity: imprisonment awaiting the death penalty. “Dialogue with death”, the memories of Arthur Koestler on the most traumatic period of his life – his stay in the prison of Seville during the Spanish Civil War – was initially published in 1937, as an important part of the “Spanish Testament”, and was in itself one of the most significant testimonial works of the 20th century on the subject of death. The perspective to which we have subjected it draws on psychoanalysis and is based, more precisely, on the Freudian theory on defenses against traumatic affects.