Exergy optimisation for cascaded thermal storage

Cascaded thermal storage, consisting of multiple Phase Change Materials (PCMs) with different melting temperatures, has been proposed to solve the problem of poor heat transfer caused by unavoidable decrease of temperature differences during heat exchange process. This paper conducts a theoretical study of the overall thermal performance for a cascaded thermal storage system. Both heat transfer rate and exergy efficiency are taken into account. The main findings are: the cascaded arrangement of PCMs enhances the heat transfer rate by up to 30%, whilst it does not always improve the exergy efficiency (-15 to +30%). Enhanced heat transfer and reduced exergy efficiency can both be attributed to the larger temperature differences caused by the cascaded arrangement. A new parameter hex (exergy transfer rate) has been proposed to measure the overall thermal performance. It is defined as the product of heat transfer rate and exergy efficiency, representing the transfer rate of the utilisable thermal energy. The simulation results indicate that the cascaded thermal storage has higher overall thermal performance than the single-staged storage despite of higher exergy efficiency loss.Peer reviewe

Ukrainos prokuratūros teisinis statusas

The scientific article is devoted to the study of the legal status of the Prosecutor’s Office in Ukraine in the context of the development of judicial reform.The historical development of the Prosecutor’s Office during the independence of Ukraine, which was carried out by transforming from the Soviet model of “supervision service” to the model of the “prosecution service” established in Europe, is analyzed.The problems of determining the place of prosecutor’s office in the system of division of state power of Ukraine are investigated. The understanding of the prosecutor’s office as adjacent to the judicial authority of the legal institute is substantiated.The purpose and objectives of the prosecutor’s office, as well as the system of its functions, are described. The problems of functional appointment of the prosecutor’s office, as well as regulation of its functions are revealed.The system of prosecutor’s office is defined and its elements are characterized. The main links of the prosecutor’s office, as well as the division of prosecutors into territorial and specialized ones are investigated.Mokslinis straipsnis skiriamas Ukrainos prokuratūros teisinio statuso tyrimui teismų reformos kontekste. Analizuojama istorinė prokuratūros raida Ukrainos nepriklausomybės laikotarpiu, kuri buvo vykdoma pereinant nuo sovietinio „priežiūros tarnybos“ modelio prie Europoje įsteigtos „prokuratūros“ modelio. Tiriamos prokuratūros padėties Ukrainos valstybės valdžios pasidalijimo sistemoje problemos. Aprašomas prokuratūros tikslas ir uždaviniai, jos funkcijų sistema. Atskleidžiamos prokuratūros funkcinio paskyrimo problemos, taip pat jų reguliavimas. Nustatoma prokuratūros sistema, apibūdinami jos elementai. Tiriami pagrindiniai prokuratūros ryšiai, taip pat prokuratūrų suskirstymas į teritorines ir specializuotas

Exergy optimisation for cascaded thermal storage

Cascaded thermal storage, consisting of multiple Phase Change Materials (PCMs) with different melting temperatures, has been proposed to solve the problem of poor heat transfer caused by unavoidable decrease of temperature differences during heat exchange process. This paper conducts a theoretical study of the overall thermal performance for a cascaded thermal storage system. Both heat transfer rate and exergy efficiency are taken into account. The main findings are: the cascaded arrangement of PCMs enhances the heat transfer rate by up to 30%, whilst it does not always improve the exergy efficiency (-15 to +30%). Enhanced heat transfer and reduced exergy efficiency can both be attributed to the larger temperature differences caused by the cascaded arrangement. A new parameter hex (exergy transfer rate) has been proposed to measure the overall thermal performance. It is defined as the product of heat transfer rate and exergy efficiency, representing the transfer rate of the utilisable thermal energy. The simulation results indicate that the cascaded thermal storage has higher overall thermal performance than the single-staged storage despite of higher exergy efficiency loss

Statistics of the network of organic chemistry

A comprehensive analysis of statistical properties of a network of organic reactions reveals several generic traits. This knowledge can be used in the development of optimal reaction sequences.</p

Task Outcomes: A Focus on Immersion Students' Use of Pronominal Verbs in Their Writing

Grade eight French immersion students worked in pairs to complete one of two tasks (jigsaw or dictogloss) based on the same story, both involving the production of a written narrative. Before completing one of these tasks requiring them to reconstruct and write a story, either from visual (jigsaw task) or from auditory (dictogloss task) stimuli, two of the four classes viewed a videotaped mini-lesson on pronominal verbs. In this article we examine the learners' use and accuracy of pronominal verbs within each task, comparing the classes that did and did not receive the mini-lesson, and across tasks, comparing the jigsaw and dictogloss classes. We found that the mini-lesson had a significant impact on the students' use of pronominal verbs in their writing.Des élèves de huitième année en immersion française ont travaillé à deux pour terminer l'une de deux tâches jigsaw ou dictogloss) basées sur la même histoire, toutes deux comportant la production d'une narration écrite. Avant de faire l'un de ces exercices qui consistaient à reconstruire et à rédiger une histoire, soit à partir d'un stimulus visuel (tâche jigsaw) soit à partir d'un stimulus auditif (tâche dictogloss), deux des quatre classes ont visionné le vidéo d'une mini-leçon portant sur les verbes pronominaux. Dans cet article, nous examinons l'utilisation et la justesse des verbes pronominaux à l'intérieur de chaque tâche, en comparant les classes qui avaient reçu la mini-leçon à celles qui ne l'avaient pas reçue, de même qu'entre les tâches, en comparant les classes jigsaw et dictogloss. Nous avons constaté que la mini-leçon avait eu un impact important sur l'utilisation par les élèves des verbes pronominaux dans leurs écrits

Interpretation of the vibrational spectra of glassy polymers using coarse-grained simulations

The structure and vibrational density of states (VDOS) of polymer glasses are investigated using numerical simulations based on the classical Kremer-Grest bead-spring model. We focus on the roles of chain length and bending stiffness, the latter being set by imposing three-body angular potentials along chain backbones. Upon increasing the chain length and bending stiffness, structural reorganisation leads to volumetric expansion of the material and build-up of internal stresses. The VDOS has two dominant bands: a low frequency one corresponding to inter- and intra-chain non-bonding interactions and a high frequency one corresponding principally to vibrations of bonded beads that constitute skeletal chain backbones. Upon increasing the steepness of the angular potential, vibrational modes associated with chain bending gradually move from the low-frequency to the high-frequency band. This redistribution of modes is reflected in a reduction of the so-called Boson peak upon increasing chain stiffness. Remarkably, the finer structure and the peaks of the high-frequency band, and their variations with stiffness, can, for short chains, be explained using an analytical solution derived for a model triatomic molecule. For longer chains, the qualitative evolution of the VDOS with chain stiffness is similar, although the distinct peaks observed for short chains become increasingly smoothed-out. Our findings can be used to guide a systematic approach to interpretation of Brillouin and Raman scattering spectra of glassy polymers in future work, with applications in polymer processing diagnostics.Comment: To appear in Macromolecule

The effectiveness of debriefing in simulation-based learning for health professionals: A systematic review

© the authors 2012. Background: Simulation is defined as a technique used to replace or amplify real experiences with guided experiences that evoke or replace substantial aspects of the real world in a fully interactive manner. The use of simulation for educational purposes began decades ago with the use of low-fidelity simulations and has evolved at an unprecedented pace. Debriefing is considered by many to be an integral and critical part of the simulation process. However, different debriefing approaches have developed with little objective evidence of their effectiveness. Objectives: The aim of this review was to identify, appraise and synthesise the best available evidence for the effectiveness of debriefing as it relates to simulation-based learning for health professionals

A systematic review of speech recognition technology in health care

BACKGROUND To undertake a systematic review of existing literature relating to speech recognition technology and its application within health care. METHODS A systematic review of existing literature from 2000 was undertaken. Inclusion criteria were: all papers that referred to speech recognition (SR) in health care settings, used by health professionals (allied health, medicine, nursing, technical or support staff), with an evaluation or patient or staff outcomes. Experimental and non-experimental designs were considered. Six databases (Ebscohost including CINAHL, EMBASE, MEDLINE including the Cochrane Database of Systematic Reviews, OVID Technologies, PreMED-LINE, PsycINFO) were searched by a qualified health librarian trained in systematic review searches initially capturing 1,730 references. Fourteen studies met the inclusion criteria and were retained. RESULTS The heterogeneity of the studies made comparative analysis and synthesis of the data challenging resulting in a narrative presentation of the results. SR, although not as accurate as human transcription, does deliver reduced turnaround times for reporting and cost-effective reporting, although equivocal evidence of improved workflow processes. CONCLUSIONS SR systems have substantial benefits and should be considered in light of the cost and selection of the SR system, training requirements, length of the transcription task, potential use of macros and templates, the presence of accented voices or experienced and in-experienced typists, and workflow patterns.Funding for this study was provided by the University of Western Sydney. NICTA is funded by the Australian Government through the Department of Communications and the Australian Research Council through the ICT Centre of Excellence Program. NICTA is also funded and supported by the Australian Capital Territory, the New South Wales, Queensland and Victorian Governments, the Australian National University, the University of New South Wales, the University of Melbourne, the University of Queensland, the University of Sydney, Griffith University, Queensland University of Technology, Monash University and other university partners

Automatic discovery and optimization of chemical processes

This paper presents the first overview of recent developments in techniques and methods that enable closed-loop optimization, also sometimes called ‘self optimization’, as well as discovery in different areas of molecular sciences. The closed-loop experimental platforms offer tremendous new opportunities by significantly increasing productivity, as well as enabling completely new types of experiments to be performed. Such experiments involve three main enabling technology areas: automated experimental systems, analytical instruments connected to automated chemoinformatics software and optimization or decision-making algorithms. We review the most exciting developments concerning robotic experiments, 3D printed lab-ware, experimental systems with multiple analytical instruments and advanced optimization algorithms based on machine learning approaches. A range of different chemical problems is described, which show the breadth of potential applications of this emerging experimental approach.This work was in part funded by EPSRC project “Closed Loop Optimization for Sustainable Chemical Manufacture” [EP/L003309/1].This is the final version of the article. It first appeared from Elsevier via http://dx.doi.org/10.1016/j.coche.2015.07.00