1,356,951 research outputs found
Fluorinated nanosized zeolitic-imidazolate frameworks as potential devices for mechanical energy storage
No full textOriginal data sets of intrusion-extrusion isotherms for three ZIF materials. They were obtained using the high-pressure water porosimetry technique. A comparison between these three materials allows for a comprehension of the effect of functional modification on the energetic characteristics of ZIFs that are subjected to the intrusion-extrusion cycle.</p
Modeling the Dynamic Behavior of Objects On Events, Messages and Methods (Extended Abstract)
No full text) Ruth Breu, Radu Grosu Institut fur Informatik, TU Munchen, D-80290 Munchen email:breur,[email protected] Events, messages and methods are three central concepts for modeling the dynamic behavior of objects. Communication between objects by sending messages, changes of object states caused by incoming events and interface design based on methods are catchwords of object-oriented analysis and design. However, in most frameworks like OMT [5], the Booch method [1] and the new method UML [2] messages, events and methods are separate concepts used in different parts and phases of system development. The interrelation between these concepts remains often unclear and is left to the interpretation of the system designer. The focus of our paper is to provide clear concepts and techniques for the dynamic modeling of objects in concurrent environments. The central description technique we rely on is a powerful variant of state transition diagrams [4, 3]. In these diagrams, tr..
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Subnanometer Topological Tuning of the Liquid Intrusion/Extrusion Characteristics of Hydrophobic Micropores
No full textIntrusion (wetting)/extrusion (drying) of liquids in/from lyophobic nanoporous systems is key in many fields, including chromatography, nanofluidics, biology, and energy materials. Here we demonstrate that secondary topological features decorating main channels of porous systems dramatically affect the intrusion/extrusion cycle. These secondary features, allowing an unexpected bridging with liquid in the surrounding domains, stabilize the water stream intruding a micropore. This reduces the intrusion/extrusion barrier and the corresponding pressures without altering other properties of the system. Tuning the intrusion/extrusion pressures via subnanometric topological features represents a yet unexplored strategy for designing hydrophobic micropores. Though energy is not the only field of application, here we show that the proposed tuning approach may bring 20-75 MPa of intrusion/extrusion pressure increase, expanding the applicability of hydrophobic microporous materials
Liquid intrusion in and extrusion from non-wettable nanopores for technological applications
No full textIn this article, we review some recent theoretical results about intrusion and extrusion of non-wetting liquids in and out of cavities of nanotextured surfaces and nanoporous materials. Nanoscale confinement allows these processes to happen at conditions which significantly differ from bulk phase coexistence. In particular, the pressure at which a liquid penetrates in and exits from cavities is of interest for many technological applications such as energy storage, dissipation, and conversion, materials with negative compressibility, ion channels, liquid chromatography, and more. Notwithstanding its technological interest, intrusion/extrusion processes are difficult to understand and control solely via experiments: the missing step is often a simple theory capable of providing a microscopic interpretation of the results, e.g., of liquid porosimetry or other techniques used in the field, especially in the case of complex nanoporous media. In this context, simulations can help shedding light on the relation between the morphology of pores, the chemical composition of the solids and liquids, and the thermodynamics and kinetics of intrusion and extrusion. Indeed, the intrusion/extrusion kinetics is determined by the presence of free energy barriers and special approaches, the so-called rare event techniques, must be used to study these processes. Usually, rare event techniques are employed to investigate processes occurring in relatively simple molecular systems, while intrusion/extrusion concerns the collective dynamics of hundreds to thousands of degrees of freedom, the molecules of a liquid entering in or exiting from a cavity, which, from the methodological point of view, is itself a challenge
Variations on the Author
No full text“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Enhancing the Sustainability of the Aviation Industry: Airlines’ Commitment to “Green” Practices
No full textThe aviation industry represents an important polluter, being responsible for increasing
environmental impacts on global scale. Aiming to approach the adoption of suitable policies
in the aviation industry towards the achievement of the national and international
sustainability goals, the present research tackles airlines’ commitment to aviation-related
environmental issues, as well as their willingness to adopt sustainable aviation fuel (i.e., bio
jet fuel) and sustainable development strategies, focusing on those companies operating
flights in the Karol Wojtyła Airport (Bari, Italy). The paper adopts the χ2 test and the logistic
regression to investigate three different hypotheses related to airlines’ headquarters, carriers’
typology (i.e., low-cost or not, flag carriers or not) and years of service. Results outline that
traditional airlines, either flag carriers or not, as well as South and North American
companies, are more likely to be aware of aviation environmental consequences, publishing
environmental reports and offering to passengers the chance to participate to climate change
reduction (e.g., through online carbon offset programs or more expensive ticket to produce
bio jet fuels). In addition, airlines transiting in Karol Wojtyła Airport show a small
willingness to share information through environmental reports and are scarcely intentioned
to make use of bio jet fuels, confirming that low-cost companies are still less attentive
towards aviation environmental issues. The present research contributes to the empirical
studies on sustainable aviation and carriers’ commitment to environmental strategies,
highlighting the need to enhance carbon offsets programs and digital technologies as the
online compensation of CO2 emissions
Love Thy Neighbor: V-Formation as a Problem of Model Predictive Control (Invited Paper)
No full textWe present a new formulation of the V-formation problem for migrating birds in terms of model predictive control (MPC). In our approach, to drive a collection of birds towards a desired formation, an optimal velocity adjustment (acceleration) is performed at each time-step on each bird's current velocity using a model-based prediction window of time-steps. We present both centralized and distributed versions of this approach. The optimization criteria we consider are based on fitness metrics of candidate accelerations that birds in a V-formations are known to benefit from, including velocity matching, clear view, and upwash benefit. We validate our MPC-based approach by showing that for a significant majority of simulation runs, the flock succeeds in forming the desired formation. Our results help to better understand the emergent behavior of formation flight, and provide a control strategy for flocks of autonomous aerial vehicles
Strategii investiţionale ca instrument al dezvoltării durabile a întreprinderilor (experiența Elveției și a Republicii Moldova)”. Teză de doctor în științe economice.
No full textTeză de doctor în științe economice. Specialitatea: 521.03 – ECONOMIE ȘI MANAGEMENT ÎN DOMENIU DE ACTIVITATE. Conducător științific: MOVILĂ Irina, dr. hab., conf. univ.ADNOTARE: Grosu Victor „Strategii investiţionale ca instrument al dezvoltării durabile a întreprinderilor (experiența Elveției și a Republicii Moldova)”, teză de doctor în științe economice, Chişinău, 2020. STRUCTURA TEZEI: introducere, trei capitole, concluzii şi recomandări, bibliografia din 173 surse, 14 anexe, 149 pagini text de bază, 19 tabele şi 49 figuri. Rezultatele obţinute sunt publicate în 14 lucrări ştiinţifice. DOMENIUL DE STUDIU: management investiţional şi strategii investiţionale. SCOPUL LUCRĂRII: constă în dezvoltarea abordării teoretice şi practice pentru eficientizarea managementului investiţional și elaborarea strategiilor investiționale eficiente în întreprinderile din Republica Moldova, în vederea creșterii competitivității lor în dezvoltarea durabilă. CZU:330.332:658.1(478+494)(043.2
- …
