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2022 ◽  
Vol 354 ◽  
pp. 00030
Author(s):  
Florin Rădoi ◽  
Ion Gherghe ◽  
Alexandru Cămărășescu

The activity of evaluation and verification of industrial ventilation installations has a strong preventive role in terms of explosion risk mainly due to the fact that of the three determining elements that can lead to an explosion phenomenon, ventilation installations can determine the presence of two elements namely the presence of fuel (gases, vapours, dusts, mists) and the source of initiation (hot surface, flame, sparks of mechanical origin, electrical sparks, static electricity, etc.). The development of experimental systems on„ which particular hazardous aspects that may occur during the operation of industrial ventilation systems can be studied are vital to avoid dangerous situations in the current operation of ventilation installations. Knowledge of the dynamics of formation of explosive / toxic / asphyxiating environments is achieved by analysing explosive mixtures in relation to specific explosive intervals and is one of the most important priorities in ensuring optimal health and safety at work in industrial activities. The information obtained by analysing the dynamics of the formation of explosive / toxic / asphyxiating atmospheres is extremely useful for personnel responsible for health and safety at work, because with their help relevant decisions can be made to ensure safety and health conditions at the level of industrial premises. The paper presents an experimental equipment usable for the study of industrial ventilation systems.


Author(s):  
Zhulavska O.O.

Purpose. The purpose of the article is to establish and analyse the cases of synesthesia metaphors retention in English-Ukrainian translations, in which “less embodied” hearing, smell and taste sensations are mapped on “more embodied” touch sensations.Methods.Synesthesia is understood as a kind of conceptual metaphor within cognitive linguistics. Research methods applied in the article are based on the achievements of cognitive linguistics and the methodology introduced and developed by L. Kovalenko and A. Martyniuk (Kovalenko, Martynyuk, 2018), which allows us to study mental models underlying metaphorical descriptions and establish the type of cognitive operation employed by the translator. We define the cognitive operation of retention following Shuttleworth’s classification (Shuttleworth, 2017) as “translation that is essentially unchanged”. The degree of conventionality and rootedness of metaphorical models in English-speaking and Ukrainian-speaking linguistic cultures is determined within the theory of probability and statistical data obtained from the Corpus of Contemporary American English (COCA) and the General Regional Annotated Corpus of Ukrainian (ГРАК). The research material for the article encounters 100 English synesthetic metaphoric descriptions, extracted from Celeste Ng’s bestseller novels “Everything I Never Told You” (Ng, 2014) and “Little Fires Everywhere” (Ng, 2017) and retained in their Ukrainian translations (Інг, 2016; 2018).Results. The study resultsare presented by the detailed analysis of synesthetic metaphorical models’ retention examples, such as HEARING / SMELL / TASTE IS TOUCHING SOFT / SHARP / HOT SURFACE. In our article, the study of synesthetic metaphoric descriptions relative frequencies showed the semantic features, which are common and divergent in their meanings for the representatives of English and Ukrainian linguacultures.Conclusions. The conducted analysis showed that synesthetic metaphoric models are retained when the difficulties faced by the translator are minimal or absent. In this case, the translator resorts to translation with a direct dictionary equivalent. Synesthetic metaphoric models with similar conventionality degrees are retained.Key words: cognitive operation, language corpus, metaphoric model, synesthetic metaphoric description, conventionality degree. Мета статті полягає у встановленні та описі випадків відтворення синестезійних метафор в англо-українських перекладах, у яких «менш втілені» слухові, нюхові та смакові відчуття проєктуються на «більш втілені» дотикові відчуття.Методи. З позицій когнітивної лінгвістики синестезію розуміємо як поширений у мові різновид концептуальної метафори. Методологічне підґрунтя дослідження становить доробок когнітивної лінгвістики та методика Л. Коваленко та А. Мартинюк (Kovalenko, Martynyuk, 2018), що уможливлює вивчення когнітивних моделей, які лежать у підґрунті метафоричних дескрипцій, і встановлення типу когнітивної операції, що застосована перекладачем. Згідно з класифікацією М. Шуттлеворфа когнітивна операція відтворення (Shuttleworth, 2017) – це «переклад, що майже не змінений». Ступінь конвенційності і вкоріненості метафоричних моделей у представників англомовної та україномовної лінгвокультур визначаємо із застосуванням теорії вірогідності та статистичних даних, отриманих із Корпусу сучасної американської англійської мови (COCA) і Генерального регіонального анотованого корпусу української мови (ГРАК). Матеріалом дослі-дження є 100 англомовних синестезійних метафор, вилучених з англомовних текстів романів-бестселерів Celeste Ng “Everything I Never Told You” (Ng, 2014) і “Little Fires Everywhere” (Ng, 2017) та відтворених в українських перекладах цих творів («Несказане» (Інг, 2016) та «Усюди жевріють пожежі» (Інг, 2018)).Результати дослідження представлені детальним аналізом прикладів відтворення синестезійних метафоричних моделей СЛУХОВІ / НЮХОВІ / СМАКОВІ ВІДЧУТТЯ Є ВІДЧУТТЯ ДОТИКУ ДО М’ЯКОЇ / ГОСТРОЇ / ГАРЯЧОЇ ПОВЕРХНІ. Проведений аналіз відносних частот вживання синестезійних метафоричних дескрипцій показав спільні та відмінні семантичні ознаки у значеннях дескрипцій, що вкорінені у свідомості представників англомовної та україномовної лінгво-культур.Висновки. Проведений аналіз показав, що синестезійні метафоричні моделі відтворюються за умови, що труднощі, з якими стикається перекладач, є мінімальними або взагалі відсутні. Водночас перекладач вдається до перекладу за допомогою прямого словникового відповідника. Відтворюються такі моделі синестезійних метафор, у яких ступінь конвенційності в англійській та українській мовах однаковий.Ключові слова: когнітивна операція, корпус мови, метафорична модель, синестезійнаметафорична дескрипція, ступінь конвенційності.


2021 ◽  
Vol 9 (4B) ◽  
Author(s):  
Samira Payan ◽  
◽  
Sameh A. Nada ◽  
A. H. Sarhaddi ◽  
◽  
...  

This paper examines the prospect of increasing or decreasing the heat transfer through a rectangular enclosure with an aspect ratio of 2 in two Rayleigh numbers 105 and 106 by optimizing its inclination angle and the parameters of a highly conductive thin fin attached to its hot surface. The enclosure is heated from below, and the dominant heat transfer mechanism within the enclosure is the free convection. Optimization is performed by particle swarm optimization algorithm. The equations of energy, continuity, and momentum for free convection heat transfer in the enclosure are discretized by the finite volume method and are numerically solved. The optimization objective is to adjust the enclosure inclination angle and the fin parameters (position and height), so that heat transfer into the cold wall becomes minimized or maximized. The attained results reveal that the heat transfer through such an enclosure can be increased significantly up to 23% by its inclination angle 20.6° and the addition of a thin fin at the optimal location 0.72 and optimal height 0.2 in Rayleigh 106. Also, the obtained results show that heat transfer can be decreased up to 32% by the slight adjustment of its inclination angle 1.7° and addition of a thin fin at the optimal location 1.41 and optimal height 0.2 in Rayleigh number 105.


Author(s):  
Seán Stewart

Abstract When drops of liquid are placed onto highly heated substrates at temperatures well above their boiling point, the drops float on a thin layer of vapour formed between the liquid and the hot surface. In a 290 year old phenomenon referred to as the Leidenfrost effect, drops freed from contact with the surface below can undergo a range of surprising and unexpected dynamical behaviour. In this paper we trace various early developments associated with the dynamics of Leidenfrost drops. By showing how many of the more recent discoveries found in the dynamic behaviour of Leidenfrost drops were either anticipated or antedated, we hope to draw attention to the long, rich, and largely overlooked history of the Leidenfrost effect and show there is much one can learn from its forgotten past.


Author(s):  
S. A. Suvorov ◽  
A. P. Shevchik ◽  
V. V. Kozlov ◽  
N. V. Arbuzova

Experimental studies of changes in the pore structure and physical and technical properties of carbonated spinel-corundum refractories under different conditions of decarbonization and the formation of a protective regulatory layer on their hot surface, suppressing decarbonization of the refractory material and mass transfer between the lining and the flow of slag melt, are presented. The results of industrial tests of carbonated spinel-corundum refractories in the working layer of the lining of a 400-ton steel-ladle lining, as well as the topography and consumption specific coefficients of refractories for the functional zones of the ladle lining, the amount of refractory destruction products of the lining during its operation are considered.


Author(s):  
Yao Zhao ◽  
Kaiyuan Peng ◽  
Jiaxin Xi ◽  
Shima Shahab ◽  
Reza Mirzaeifar

Abstract Locomotion is a critically important topic for soft actuators and robotics, however, the locomotion applications based on two-way shape memory polymers have not been well explored so far. In this work, a crosslinked poly(ethylene-co-vinyl acetate) (cPEVA)-based two-way shape memory polymer is synthesized using dicumyl peroxide (DCP) as the crosslinker. The influence of the DCP concentration on the mechanical properties and the two-way shape memory properties is systematically studied. A Venus flytrap-inspired soft actuator is made by cPEVA, and it is shown that the actuator can efficiently perform gripping movements, indicating that the resultant cPEVA SMP is capable of producing large output force and recovering from large deformations. This polymer is also utilized to make a self-rolling pentagon-shaped device. It is shown that the structure will efficiently roll on a hot surface, proving the applicability of the material in making sophisticated actuators. With introducing an energy barrier, jumping can be accomplished when the stored energy is fast released. Finite element simulations are also conducted to further understand the underlying mechanisms in the complex behavior of actuators based on cPEVA SMP. This work provides critical insights in designing smart materials with external stimulus responsive programmable function for soft actuator applications.


2021 ◽  
Author(s):  
Sang-Guk Kang ◽  
Je Ir Ryu ◽  
Austen H. Motily ◽  
Prapassorn Numkiatsakul ◽  
Tonghun Lee ◽  
...  

Abstract Energy addition using a hot surface probe is required for reliable ignition of aircraft compression ignition engines running on fuel variations and at altitude conditions. Thus, durability of the hot surface probe is crucial for application in these engines. Thermo-mechanical stress is one of the key parameters that determine durability, which requires an accurate prediction of the transient temperature field based on well-defined boundary conditions representing the dynamic and complex fluid flow inside engines. To meet this requirement, the present study focuses on transient thermo-mechanical stress analysis using a sequentially coupled CFD-FEA approach to understand transient thermo-mechanical responses of the hot surface probe. A 3D transient reacting flow simulation was conducted first using CONVERGE software, the results of which were exported to map thermal and pressure boundary conditions onto a structural finite element mesh. Transient thermo-mechanical stress analysis was performed sequentially using ABAQUS software utilizing the mapped boundary conditions. The results such as transient temperature history, resultant thermo-mechanical stress, displacement, potential failure modes, etc. were critically reviewed, which can provide helpful information for further design improvement.


2021 ◽  
Vol 8 ◽  
Author(s):  
Jun Pan ◽  
Fangping Cheng ◽  
Fei Yu ◽  
Yongqiang Shi ◽  
Fan Sun ◽  
...  

Calanus sinicus, a temperate copepod with a lethal temperature >27°C, is one of the key species in Chinese coastal marine ecosystems. The C. sinicus population increases in spring and declines in early summer annually due to increasing water temperature. Numerous C. sinicus individuals then congregate in the Yellow Sea Cold Water Mass (YSCWM) and remain under the thermocline from early summer to early autumn. Development and reproduction is halted in this cold and foodless bottom water and they avoid ascending to the hot surface water, which is regarded as an over-summering strategy. Based on discrete water sampling approaches, previous studies demonstrated that higher chlorophyll a (Chl a) levels appeared in the mixed hot surface water layer; however, the subsurface chlorophyll a maximum layer (SCML) has seldom been described. In the present study, various probes and a visual plankton recorder (VPR) were used to determine the fine vertical distributions of environmental factors and C. sinicus. VPR observations showed the ecological responses in fine scale and indicated that few C. sinicus individuals ascend at night, the main population preferred to remain below the SCML all day long. The results demonstrated that a constant thin SCML existed in the YSCWM area, and that the SCML location coincided with or was beneath the thermocline and halocline layers, where the temperature was suitable for C. sinicus. The relationship between abundance and Chl a, showed the diel vertical migration trend of C. sinicus to feed at night in the YSCWM area. In addition to temperature as a main influencing factor, dissolved oxygen concentrations and column depth were also influencing factors. Therefore, in addition to avoiding high surface temperature, energy supplement may be an important driving force confining the diel vertical migration of C. sinicus in the Yellow Sea in summer.


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