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Journal articles on the topic 'Ambient envelop-'
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1
Takao Katsura, Tomoya Ohara, Taichi Kamada, Katsunori Nagano, and Saim Memon. "Analysis of indoor environment and insulation performance of residential house with double envelope vacuum insulation panels." International Journal of Solar Thermal Vacuum Engineering 3, no. 1 (August 25, 2021): 15–28. http://dx.doi.org/10.37934/stve.3.1.1528.
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Double envelope vacuum insulation panels (VIPs) have a possibility to significantly increase the service lifetime. In this paper, double envelope VIPs were produced and installed in the residential house. The performance of installed VIPs was evaluated by using the measuring data of heat flux meter. In addition, the total energy, the heating load and the indoor thermal environment of this house were measured and analysed. The average heating load and the average temperature difference between room temperature and ambient air temperature on the representative day was 2.49 kW and 29.9 oC, respectively. The heat loss coefficient per floor area was estimated as 0.69 W/(m2K) and it was almost the same as the value calculated at the time of design. The result of indoor environment measurement showed that the room temperature was maintained at around 20 oC and PMV was -0.5 oC or higher although the outside air temperature fluctuated between -5 oC and -10 oC. The effective thermal conductivities of double envelop VIPs were all estimated as 0.01 W/(mK) or less. It is considered that the insulation performance of the vacuum insulation panels is maintained.
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Ndukwu, Macmanus Chinenye, Merlin Simo-Tagne, Ifiok Edem Ekop, Mathew I. Ibeh, Maureen A. Allen, Fidelis I. Abam, Lyes Bennamoun, and Razika Kharchi. "Energy in buildings: A review of models on hygrothermal transfer through the porous materials for building envelop." Future Technology 2, no. 4 (November 15, 2023): 33–44. http://dx.doi.org/10.55670/fpll.futech.2.4.4.
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The hygrothermal transfer is very important for the design of a building envelope for thermal comfort, economic and energy analysis of the building envelope. The lack of reference materials on models of moisture and temperature behavior in the building, including wooden walls, is a challenge. This paper reviewed the hygrothermal transfer models for building walls. Energy and mass conservation equations with boundary and input conditions were presented in this paper for concrete, bricks, and wooden walls. The review showed the presence of mainly physical-based models, while there is a dearth of data-based models. The influence of the type of wall, orientation, thickness, the density of the material, and climatic variations on the temperature and moisture evolutions within the building materials influenced the model mechanisms. Future research gaps should include shrinkage influence on hygroscopic materials like wood due to their behavior under ambient conditions. Data-based models should be explored too.
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Yan, Gongxing, Bin Teng, Azher M. Abed, Ahmed Deifalla, Hossein Mehdizadeh Youshanlouei, Zuhair R. Abdulghani, and Hazim Moria. "Computational fluid dynamics simulation of a designed envelop contenting phase change material and imposed solar heat flux and ambient air." Journal of Energy Storage 58 (February 2023): 106184. http://dx.doi.org/10.1016/j.est.2022.106184.
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Ayache, Ahmed, and Othman Echi. "The envelope of a subcategory in topology and group theory." International Journal of Mathematics and Mathematical Sciences 2005, no. 21 (2005): 3387–404. http://dx.doi.org/10.1155/ijmms.2005.3387.
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A collection of results are presented which are loosely centered around the notion of reflective subcategory. For example, it is shown that reflective subcategories are orthogonality classes, that the morphisms orthogonal to a reflective subcategory are precisely the morphisms inverted under the reflector, and that each subcategory has a largest “envelope” in the ambient category in which it is reflective. Moreover, known results concerning the envelopes of the category of sober spaces, spectral spaces, and jacspectral spaces, respectively, are summarized and reproved. Finally, attention is focused on the envelopes of one-object subcategories, and examples are considered in the category of groups.
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Kanoria, Akshay A., and Rajkumar S. Pant. "Winged Aerostat Systems for Better Station Keeping for Aerial Surveillance." Advanced Materials Research 433-440 (January 2012): 6871–79. http://dx.doi.org/10.4028/www.scientific.net/amr.433-440.6871.
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An aerostat is a tethered balloon with an aerodynamically shaped envelope containing a lighter-than-air gas that generates bulk of the lifting force. Aerostats are used extensively as an aerial platform for many scientific and commercial applications. Conventional aerostats envelopes have an ellipsoidal shape, due to which they suffer from a large amount of horizontal displacement (called blowby) due to the ambient winds. If the drag force acting on aerostat is high, the resulting blowbyis higher and a longer tether is required to maintain the specified operating altitude; this results in lower payload capacity. Recent studies have shown that winged aerostats (which have an envelope with airfoil cross-section) can reduce blowbydue to a much higher lift/drag ratio. This paper presents a comparative analysis of the operational effectiveness of a winged and conventional aerostat for scientific data gathering in lower Himalayas at various ambient wind speeds. The winged aerostat is seen to be much smaller in size, and has a much lower reduction in operating altitude due to blowby. The paper also describes the design of a prototype winged aerostat currently under development.
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Kubullek, M., Z. Wang, K. von der Brelje, D. Zimin, P. Rosenberger, J. Schötz, M. Neuhaus, et al. "Single-shot carrier–envelope-phase measurement in ambient air." Optica 7, no. 1 (January 7, 2020): 35. http://dx.doi.org/10.1364/optica.7.000035.
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Toure, Pape Moussa, Younouss Dieye, Prince Momar Gueye, Mactar Faye, and Vincent Sambou. "Influence of envelope thickness and solar absorptivity of a test cell on time lag and decrement factor." Journal of Building Physics 43, no. 4 (July 12, 2019): 338–50. http://dx.doi.org/10.1177/1744259119863446.
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This work deals with the influence of envelope thickness and solar absorption on the time lag and the decrement factor. For this, a test cell of 1 m3 of volume is built with a material commonly used in construction in Senegal, the compressed earth brick stabilized with cement. The ambient-air temperature inside and outside of test cell and solar direct normal irradiance is measured. The test cell is modeled using EnergyPlus software. The comparison of experimental and theoretical ambient-air temperature puts out a great linear showing the reliability of the model. The time lag and the decrement factor are calculated using the air-sol equivalent temperature of the test cell and the inside ambient-air temperature. The time lag and decrement factor of the compressed stabilized earth brick envelope are respectively 0.22 and 6.6 h showing the good thermal inertia of those bricks. A parametric study is performed to determine the effect of envelope thickness and solar absorptivity on the time lag and decrement factor. The results show that the decrement factor decreases with envelope thickness while the time lag increases linearly and that an envelope thickness of 32 cm has a decrement factor of around zero with a maximum time lag of about 12 h for this type of material. The envelope’s solar absorption has a moderate effect on the decrement factor and time lag.
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Furduev, A. V. "The two domains in envelope spectrum of ocean ambient noise." Journal of the Acoustical Society of America 105, no. 2 (February 1999): 1361. http://dx.doi.org/10.1121/1.426446.
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Zhao, Haoran, Elliott T. Gall, and Brent Stephens. "Measuring the Building Envelope Penetration Factor for Ambient Nitrogen Oxides." Environmental Science & Technology 53, no. 16 (July 19, 2019): 9695–704. http://dx.doi.org/10.1021/acs.est.9b02920.
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Lowrey, S., and G. Reboux. "Rotary Compressor Performance at Low Ambient Temperatures." International Journal of Air-Conditioning and Refrigeration 28, no. 04 (December 2020): 2050037. http://dx.doi.org/10.1142/s2010132520500376.
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Small rotary compressors are used in domestic heat pump appliances, for example, in domestic dehumidifiers and heat pump clothes dryers. Compressor performance curves provided by the manufacturer can be based on testing at relatively high ambient temperatures, in some cases as high as 35∘C. This can be much higher compared with the ambient temperature in which the compressor operates when, for example, it is installed in a domestic dehumidifier which can operate in ambient temperatures as low as 10∘C. We have developed a compressor calorimeter to test a small R134a rotary compressor extracted from a commercial domestic dehumidifier and use this to measure compressor performance parameters including the isentropic and volumetric efficiencies and the compressor heat loss fraction. The performance testing has been carried out at ambient temperatures 10∘C, 15∘C, 20∘C and 25∘C for a fixed relative humidity of 70% to compare how the compressor performance varies with the ambient temperature, and to determine how well the compressor performs outside of the performance envelope provided by the manufacturer. The results show that isentropic and volumetric efficiency of these small compressors is relatively insensitive to variation in ambient temperature, even outside of the performance envelope provided by the manufacturer. However, the compressor heat loss fraction can, on average, double from 15% to 30%, between operation at ambient 25∘C and ambient 10∘C. The data obtained in this work is used to construct compressor sub-models for certain ambient temperatures. We show how these sub-models can be used to improve a domestic dehumidifier model for operation at low ambient conditions within the evaporator frosting regime and good agreement is obtained between experimental and simulated data. The authors are not aware of a domestic dehumidifier model designed to work at ambient temperatures within the frosting regime.
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Huifen, Zou, Fei Yingchao, Yang Fuhua, Tang Hao, Zhang Ying, and Ye Sheng. "Mathematical Modeling of Double-Skin Facade in Northern Area of China." Mathematical Problems in Engineering 2013 (2013): 1–10. http://dx.doi.org/10.1155/2013/712878.
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This paper focuses on the operation principles of the double-skin facade (DSF) in winter of severe cold area. The paper discussed the main influence factors of building energy consumption, including the heat storage cavity spacing, the air circulation mode, the building envelope, and the building orientation. First, we studied the relationship among the thermal storage cavity spacing, the temperature distribution in the cavity of the DSF, and the indoor temperature. Then, we discussed the influence on the ambient temperature in the building exerted by the air circulation system of the double-skin facade. Finally, we analyzed the influence on the whole building energy consumption of the DSF buildings under the situation of different building envelopes and different building orientations. Based on the results of the numerical simulation, the paper put forward an operation strategy analysis of the DSF buildings in severe cold area, in order to achieve the purpose of building energy saving.
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KEHINDE, Tolulope Olaitan, Moruf Ayodele ADEBISI, Isiaq Omoniyi LAWAL, Muibat Modupe SHITTU, and Evelyn Ese OKWI. "Seed longevity characteristics of tomato (Solanum lycopersicum L.) genotypes stored with different packaging materials under ambient tropical humid conditions." Acta agriculturae Slovenica 118, no. 1 (April 4, 2022): 1. http://dx.doi.org/10.14720/aas.2022.118.1.2444.
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<p class="042abstractstekst"><span lang="EN-US">Tomato seeds have a high commercial value, and the loss of seed physiological quality over time is demonstrated by their low storability unless hermetic conditions are used. This study aimed to store and preserve seed quality under ambient conditions using different packaging materials such as plastic bottles, glass bottles, paper envelope, earthen pot, polyethylene bag, galvanized iron tin. Freshly harvested seeds of four tomato genotypes were packed inside different containers and then sealed and stored for eight months under ambient humid tropical conditions. Data collected were subjected to Analysis of Variance (ANOVA) and means were separated using Tukey’s HSD test at 5 % probability level. The result revealed that envelope and earthen pot were not ideal for tomato seed storage for long time, because seed stored in air tight containers maintained desired seed quality than non- airtight packaging materials. Glass bottle was identified as the best packaging material in maintaining seed quality of tomato throughout the storage period. Tomato seeds could be stored up to between 120 and 180 days under ambient conditions, depending on genotype and storage medium of the seed lot. </span></p>
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Chapman, Nicholas L., Jacqueline A. Davidson, Paul F. Goldsmith, Martin Houde, Woojin Kwon, Zhi-Yun Li, Leslie W. Looney, et al. "ALIGNMENT BETWEEN FLATTENED PROTOSTELLAR INFALL ENVELOPES AND AMBIENT MAGNETIC FIELDS." Astrophysical Journal 770, no. 2 (June 6, 2013): 151. http://dx.doi.org/10.1088/0004-637x/770/2/151.
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Yang, Wan, and Linsey C. Marr. "Mechanisms by Which Ambient Humidity May Affect Viruses in Aerosols." Applied and Environmental Microbiology 78, no. 19 (July 20, 2012): 6781–88. http://dx.doi.org/10.1128/aem.01658-12.
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ABSTRACTMany airborne viruses have been shown to be sensitive to ambient humidity, yet the mechanisms responsible for this phenomenon remain elusive. We review multiple hypotheses, including water activity, surface inactivation, and salt toxicity, that may account for the association between humidity and viability of viruses in aerosols. We assess the evidence and limitations for each hypothesis based on findings from virology, aerosol science, chemistry, and physics. In addition, we hypothesize that changes in pH within the aerosol that are induced by evaporation may trigger conformational changes of the surface glycoproteins of enveloped viruses and subsequently compromise their infectivity. This hypothesis may explain the differing responses of enveloped viruses to humidity. The precise mechanisms underlying the relationship remain largely unverified, and attaining a complete understanding of them will require an interdisciplinary approach.
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Fidelis, Ana Paula Santos, Andreza Barboza da Silva, Myllena Matias da Silva, and Mariana Roberta Pedrosa Dias. "Abordagem da educação ambiental em uma escola estadual da região metropolitana do Recife." Natural Resources 3, no. 2 (January 7, 2014): 6. http://dx.doi.org/10.6008/ess2237-9290.2013.002.0001.
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Educação ambiental é um processo contínuo de aprendizagem, em que a escola e a sociedade, devem estar envolvidas, pois a escola é a peça fundamental no processo de conscientização dos alunos em relação aos problemas ambientais, e assim transformando os alunos em cidadãos conscientes e comprometidos com o futuro. Para sensibilizar os alunos utilizou-se de um problema ambiental enfrentado pela escola que são as enchentes, visto que a escola é localizada nas redondezas do canal do Jordão, sempre que chove intensamente esse canal transborda e impossibilita a passagem de pedestres e dos ônibus e assim causando um transtorno, então o objetivo deste estudo foi sensibilizar e demonstrar ao aluno, que o impacto ocorrido é consequência de hábitos inadequados como jogar lixo no canal. Realizou- se visitas em uma escola da Rede Estadual de Ensino no bairro do Jordão Baixo localizada na Região Metropolitana do Recife numa turma de quinta série composta por 21 alunos que participaram das atividades. No primeiro momento foi abordado a questão do lixo, reciclagem, coleta seletiva, tipos de lixos, questões geográficas, causas e consequência provocada pelo acúmulo de lixo incorretamente e educação ambiental, nesta primeira etapa abordou-se os impactos ambientais localizados na comunidade escolar, pois a educação ambiental não deve ser tratada apenas apontando as atitudes corretas e incorretas o ideal é sensibilizar o aluno demonstrando os problemas locais. Utilizou- se um jogo para discussão desses temas e posteriormente foi aplicado um questionário abordando os conhecimentos e conceitos trabalhados na atividade. O jogo Show do Lixão é constituído de perguntas e respostas, por isso, a turma foi separada em dois grupos denominados de uva e maçã, cada grupo recebeu um envelope de perguntas e respostas sobre causas e consequências de armazenamento inadequado do lixo, como por exemplo, enchentes provocadas pelo acúmulo de lixo em bueiros, coleta seletiva e entre outras questões. Quando questionados o que eles entendem por educação ambiental 61,9% alunos afirmaram que seria a pratica de preservação do meio ambiente e 38,09% deixaram a alternativa em branco; quando questionados se lixo era tudo aquilo que ninguém quer e sem utilidade 61,9% alunos disseram que a alternativa era falsa e 38,09% disseram que era verdadeira; quando questionados se lixo é qualquer resíduo proveniente das atividades humanas 61,9% disseram que alternativa era verdadeira e 38,09% disseram que a alternativa era falsa. Ao fim desse estudo percebe-se que mais de 50% dos alunos entendem o que é educação ambiental teoricamente, e tem conhecimento da importância da preservação do meio ambiente, mas não realizam atitudes que preservem o meio ambiente. Com a aplicação do jogo Show do lixão percebeu-se que o tema educação ambiental esta sendo abordado de forma transdisciplinar nesta escola. Os alunos entendem a relação causa consequência, ou seja, o quanto mais o homem prejudica o meio ambiente o homem será privado de recursos naturais nas gerações futuras.
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Boutet, Maria Laura, and Alejandro Luis Hernández. "Validación de propuestas de optimización ambiental de un jardín de infantes de tipología compacta, en clima muy cálido-húmedo." Revista Hábitat Sustentable 12, no. 1 (June 30, 2022): 24–43. http://dx.doi.org/10.22320/07190700.2022.12.01.02.
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This article presents the validation procedure of optimization proposals for a compact-typology kindergarten prototype, following passive bioclimatic design guidelines, using dynamic simulation physical models calibrated with onsite measurements. The objective is to verify the parameters for the glazed area (gA), weighted average solar absorptance (), and total envelope area (envelopeA), using them as input data to obtain correlations of glazing Factors (gF) into a tool to estimate optimal glazed areas, aiming at integrating thermal and visual comfort in the design of educational spaces, in the Very Hot-Humid climate of the Argentine Northeast. As a result, a reduction of up to 72% was obtained in November, the most unfavorable month for school activities, for cooling requirements, by lowering the solar absorptance of exterior surfaces to 0.25, with a glazed area per floor area ratio of 17%, which made noteworthy improvements possible in the spatial daylight distribution, a key resource for the comprehensive development of children from Initial Schooling Levels.
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Choi, Dong Hee, and Dong Hwa Kang. "Infiltration of Ambient PM2.5 through Building Envelope in Apartment Housing Units in Korea." Aerosol and Air Quality Research 17, no. 2 (2017): 598–607. http://dx.doi.org/10.4209/aaqr.2016.06.0287.
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Kumar, S., R. Sheeja, Perumal Pitchandi, B. Mullai Sudaroli, Chandrasekar Pichandi, and G. S. Sai Krishnan. "Numerical analysis of PCM integrated year-round thermal energy savings building for composite climatic conditions." IOP Conference Series: Earth and Environmental Science 1100, no. 1 (December 1, 2022): 012004. http://dx.doi.org/10.1088/1755-1315/1100/1/012004.
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Abstract Incorporating PCM in building envelopes is a promising energy-saving technique. Because the PCM container maintains a constant temperature when storing and retrieving energy. The PCM is used in building envelopes to diminish solar irradiation, reducing heat penetration and lowering heating and cooling loads. It’s vital to get the right PCM for different climates. Because the ambient air temperature fluctuated a lot throughout the year. PCM temperature effectiveness is highly determined by local ambient weather conditions. It is challenging to design the PCM integrated building for year-round thermal regulation. This research discussing PCM’s thermal energy effectiveness in building walls for decreasing interior temperature variance in composite climatic systems using numerical simulation using EnergyPlus software.
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Silvester, Warwick B., Janet K. Silvester, and John G. Torrey. "Adaptation of nitrogenase to varying oxygen tension and the role of the vesicle in root nodules of Alnus incana ssp. rugosa." Canadian Journal of Botany 66, no. 9 (September 1, 1988): 1772–79. http://dx.doi.org/10.1139/b88-243.
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Growth of Alnus incana ssp. rugosa plants with root systems at Po2 levels of 5, 21, and 40 kPa showed no significant differences among treatments over a 6-week period. Nitrogenase activity of attached nodulated foot systems run in an opencuvette continuous-flow system generally was responsive to Po2 over a broad range around the optimum. Plants expressed acetylene-induced and oxygen-induced transient declines in nitrogenase activity, from which they spontaneously recovered. Nitrogenase activity was seldom stable at any one Po2 during assay with apparent adaptation to both above- and below-ambient Po2 Nodule morphology showed quantitative decreases in aeration pathways as ambient Po2 was increased, with air spaces in the cortex and infected tissue being significantly affected. The major change in response to Po2 was the change in vesicle structure. Vesicles from nodules at low Po2 showed a vanishingly thin vesicle envelope under dark-field microscopy, while at high Po2 vesicles appeared very bright and apparently thickened. The results suggest that the major barrier to O2 diffusion in Alnus nodules is the vesicle envelope of the bacterium.
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Staszczuk, Anna, and Tadeusz Kuczyński. "Cumulative Multi-Day Effect of Ambient Temperature on Thermal Behaviour of Buildings with Different Thermal Masses." Energies 16, no. 21 (October 31, 2023): 7361. http://dx.doi.org/10.3390/en16217361.
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In most studies, the effect of the thermal capacity of the building envelope on changes in internal temperatures is reduced to a 24 h period. During this period, daytime heat gains are balanced by nighttime heat losses. The maximum indoor temperature, the diurnal variation of the indoor temperature and the time lag between the occurrence of the maximum daily temperature determine the effect achieved. The aim of the article was to show that the effect of the thermal capacity of a building on the indoor temperature is not limited to 24 h but accumulates over a period of several days, mainly depending on the temperature and solar radiation history of the previous days. As a result, contrary to what some studies have suggested, the bedrooms of heavier buildings remained significantly colder at night during periods of prolonged high outdoor temperatures. The results obtained may fundamentally influence the perception of the effect of using the high thermal capacity of the building envelope to reduce high indoor temperatures in hot weather.
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Karanafti, A. C., and T. G. Theodosiou. "Investigation of the envelope’s thermal transmittance influence on the energy efficiency of residential buildings under various Mediterranean region climates." IOP Conference Series: Earth and Environmental Science 899, no. 1 (November 1, 2021): 012009. http://dx.doi.org/10.1088/1755-1315/899/1/012009.
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Abstract Improving the energy efficiency of residential buildings is of outmost importance for reducing their environmental footprint. Recent studies demonstrate that a highly insulated building envelope may burden the building’s performance during the cooling period, especially in regions with hot summers. In this study, the energy performance of a residential building in different Mediterranean regions (Jordan, Greece, Iraq, Egypt, Syria, Morocco, Cyprus, Saudi Arabia, Libya, and Spain) is investigated. Two thermal transmittance values are applied to the building shell, a scenario with a very low one and a scenario with a higher one, to examine under which conditions the cooling performance is improved. A dynamic insulation configuration is also implemented, and its operation is studied for the cooling period of each city. It is concluded that in Southern European and Northern African regions building envelopes with lower thermal resistances perform better, while in even Southern regions an increased thermal resistance may prevent the heat from entering the building more effectively. With the switching insulation system, a great reduction in the cooling demands was reported, which reached up to 50% in Spain, and it was shown that in the southern regions the configuration’s operation should be customized to the ambient conditions to optimize its performance.
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Ma, N., Q. Zhang, and W. W. Braham. "Rethinking building envelope design: Machine learning approaches to evaluate its impact on indoor ozone exposures." Journal of Physics: Conference Series 2600, no. 10 (November 1, 2023): 102002. http://dx.doi.org/10.1088/1742-6596/2600/10/102002.
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Abstract Ozone is widely recognized as an ambient air contaminant that causes acute and chronic health effects. However, there is a limited number of studies investigating indoor exposures to ozone in occupied houses and linking design variables to the predictive power of indoor ozone levels. This study focuses on typical envelope airflow paths used in residences in the Philadelphia area in the United States. The model development draws from the field data, including indoor and outdoor ozone concentration, environmental parameters, and building characteristics from four building envelopes. Five machine learning algorithms (i.e., support vector machine, lasso regression, random forest, Bayesian bridge regression, and gradient boosting) are employed, with indoor ozone concentration as the dependent variable, as it indicates how the hot and sunny weather that might lead to the possibility of indoor air quality (IAQ) alerts due to ozone. The results showed that gradient boosting model based on all field measurements had the highest R-squared value of 0.974 and low enough root mean square error (RMSE) and mean absolute error (MAE) which are 1.182 and 0.788, respectively. We conclude that indoor ozone forecasting model based on inputting environmental survey (ES) in addition to either design variables or indoor environment characteristics can effectively predict and can therefore be used at the building design phase to improve healthy living environments.
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Mao, Ho-Kwang, and Wendy L. Mao. "Geomimicry—Liberating high-pressure research by encapsulation." Matter and Radiation at Extremes 7, no. 6 (November 1, 2022): 068102. http://dx.doi.org/10.1063/5.0126898.
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High pressures induce changes of properties and structures that could greatly impact materials science if such changes were preserved for ambient applications. Mimicking the geological process of diamond formation that the pressures and high-pressure phases in diamond inclusions can be preserved by the strong diamond envelope, we discuss the perspectives that such process revolutionizes high-pressure science and technology and opens a great potential for creation of functional materials with extremely favorable properties.
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Cardoso da Silva, Filipe, and Ana Belchior Melícias. "ROSA DE JERICÓ E O ENVELOPE INSTITUCIONAL." Revista Portuguesa de Psicanálise 41, no. 2 (December 31, 2021): 74–85. http://dx.doi.org/10.51356/rpp.412a6.
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Utilizaremos a metáfora da Rosa de Jericó para entrelaçar duas questões que a menina a quem chamaremos Rosa nos apresentou, com invulgar capacidade expressiva e transformativa. De um lado, a capacidade de sobrevivência psíquica (resiliência? competências inatas?) perante um ambiente traumático de violência, abandono, negligência, ruturas e descontinuidades. De outro, a hipótese de que as inúmeras instituições que acolheram este fio de descontinuidade funcionaram como uma pele psíquica (Bick, 1968/1991), um envelope institucional (Houzel, 2010), e como «anjos no quarto do bebé» (Lieberman et al., 2005), que permitiram que Rosa se nutrisse o suficiente para chegar, sem se fraturar psiquicamente, ao acompanhamento psicoterapêutico, também em instituição. Finalmente, foi este que lhe permitiu reintegrar-se progressivamente: voltar ao deserto, atravessá-lo acompanhada, preparar-se para a busca de um terreno-família, onde pudesse finalmente desenvolver-se. Tentaremos ilustrar essa concatenação entre a construção da subjetividade, o papel das instituições de suporte e o trabalho psicoterapêutico em instituição.
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Qiu, Jiayi, Haixi Zhang, Jialu Liu, and Yanhua Liu. "The Impact of Indoor Air Humidity on the Infiltration of Ambient Particles." Buildings 14, no. 4 (April 6, 2024): 1022. http://dx.doi.org/10.3390/buildings14041022.
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Ambient particles contribute to occupant exposure as they infiltrate indoor environments through building envelope cracks, impacting indoor air quality. This study investigates the impact of indoor air humidity on the infiltration of ambient particles, highlighting humidity’s crucial role in influencing particle dynamics in indoor environments. Employing a controlled chamber system, we conducted experiments to quantify the infiltration of size-resolved particles under varying relative humidity (RH) conditions. Both the total number and the mass concentration of particles increased with RH in the experimental chamber. The smallest particles (0.3–0.4 μm) experienced reduced infiltration at higher RH levels due to hygroscopic growth, while intermediate-sized particles showed increased infiltration, resulted from coagulation effects. Large particles (>1.0 μm) demonstrated reduced infiltration factors, caused by lower penetration and higher deposition rates, with minimal impact from RH changes. Our findings reveal that RH influences particle hygroscopic growth, deposition rate, and coagulation process, thereby affecting indoor particle size distribution and concentration.
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HACKENBERG, PETER, and GOTTFRIED MANN. "Parallel weak envelope solitons in multi-ion plasmas." Journal of Plasma Physics 61, no. 4 (May 1999): 633–44. http://dx.doi.org/10.1017/s0022377899007631.
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Heavy ions frequently appear as minor components in space plasmas, for example as charged helium in the solar wind and heavy ions in the vicinity of comets. Both the different components of ions and the associated plasma waves are observed by extraterrestrial in situ measurements. These plasma waves appear as large-amplitude magnetic field fluctuations in space plasmas. They must be described appropriately by means of multifluid equations. Because of the nonlinear nature of these waves, we here investigate nonlinear waves in multi-ion plasmas. Solitary waves that can only exist in a magnetized bi-ion plasma are presented. We employ a perturbation theory at the linear solution of a left-hand circularly polarized, low-frequency (below the proton gyrofrequency) plasma wave and take only the first nonlinear terms into account. Thus the multifluid equations are reduced to a single equation of the type of a nonlinear Schrödinger equation. The derived soliton solution is valid for magnetic field amplitudes lower than 10% of the ambient unperturbed magnetic field. The solutions are discussed for plasma parameters that are typical of the solar wind. A density enhancement can be observed within the soliton, where the helium ion density is more enhanced than the proton density.
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Weiter, Ross. "Integrity considerations for dehydration of carbon dioxide." APPEA Journal 62, no. 2 (May 13, 2022): S200—S204. http://dx.doi.org/10.1071/aj21040.
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Carbon capture, sequestration, and utilisation is widely considered to be one of the key enablers to decarbonising the economy. Transportation of carbon dioxide (CO2) is a key focal area in any carbon capture and storage project. While dehydration of natural gas for transportation is well understood and regulated, the same cannot be said for CO2. This is due to its immaturity relative to natural gas and due to properties of CO2 being radically different to those of hydrocarbons. One of those physical properties is the ability of CO2 to saturate with water. Excessive water in CO2 transportation and injection systems can cause integrity and operability problems such as corrosion, blockages from hydrates and water ice, and slugging due to liquid water dropout. Contaminants present in the CO2 stream such as methanol and hydrogen can also have a significant impact on the phase envelope. Therefore, to mitigate these issues, dehydration specifications need to be selected based on phase envelopes and other important project parameters such as corrosion, ambient temperatures, and hydrate formation. For every individual project, a selection needs to be made to determine the applicable CO2 dehydration specification, considering both the normal and transient operating conditions. Based on the selected specification, the most suitable method for implementing dehydration should be selected, along with the optimum location of the dehydration equipment in the multi-stage pressure-boosting plant. This study explores these challenges and presents a methodology for overcoming them.
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Amaral, Denise Campos, Geovanna Rafael Martins, Larissa Caldeira Alves Mendes, Diogo Rodrigues Cruvinel, Mayara Barbosa Viandelli Mundim, and Carolina Cintra Gomes. "REDUÇÃO DE RESÍDUOS NA CLÍNICA ODONTOLÓGICA APÓS IMPLANTAÇÃO DO PROTOCOLO DE FLUXO RADIOGRÁFICO DIGITAL." Scientific Investigation in Dentistry 25, no. 1 (November 5, 2020): 17–24. http://dx.doi.org/10.37951/2317-2835.2020v25i1.p17-24.
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Objetivo: O objetivo neste estudo foi contabilizar a quantidade de resíduos, provenientes dos filmes radiográficos convencionais, que deixou de ser produzido com a implantação do sistema de imagem digital no Centro de Diagnóstico por Imagem da UniEVANGÉLICA (CDI). Material e Métodos: Foram contabilizados 2554 exames intrabucais realizados durante o ano letivo de 2017. Cada componente do filme radiográfico intrabucal (película de chumbo, papel preto e envelope plástico) foi pesado individualmente e comparados com o peso do plástico usado para isolar o receptor de imagem do tipo placa de fósforo durante a tomada radiográfica. Esses dados possibilitaram o cálculo da quantidade de resíduos gerados a partir desses exames. Resultados: Após teste de porcentagem simples observou-se uma redução de 97% em peso total de resíduos gerados com o uso da Radiologia Digital. Conclusão: A partir dos resultados percebe-se uma redução significativa na quantidade de resíduos gerados pela radiologia após a implantação do sistema de imagem digital no CDI. Atualmente o CDI oferece aos pacientes exames de maior qualidade se adequando ao ambiente de Sistema de Comunicação e Arquivamento de Imagens (PACS) além de apresentar um impacto ambiental positivo com a redução de resíduos gerados.
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Kamegai, Kazuhisa, Masaaki Hiramatsu, Takahiro Hayakawa, Ken'ichi Tatematsu, Tetsuo Hasegawa, Toshikazu Onishi, and Akira Mizuno. "Submillimeter-wave observations of outflow and envelope around the low mass protostar IRAS 13036-7644." Proceedings of the International Astronomical Union 2, S237 (August 2006): 432. http://dx.doi.org/10.1017/s1743921307002207.
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The interaction between molecular outflow from a protostar and ambient molecular cloud would play an important role in dissipating circumstellar envelope, changing chemical composition, and triggering next generation star formation. In order to investigate the interaction in submillimeter wavelength, we have made line observations toward the low mass protostar IRAS 13036-7644 (Class 0/I) in the Cha II dark cloud. Although millimeter observations found CO outflow and evidence of mass infall toward the protostar (e.g. Lehtinen 1997), no submillimeter observation has been reported so far.
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Cai, Huikang, Shuaijie Sha, Tai Xu, Yannan Li, and Hanzhong Tao. "Numerical simulation of indoor air distribution and wall heat storage under accident conditiohs in a main control room." Thermal Science, no. 00 (2024): 100. http://dx.doi.org/10.2298/tsci240119100c.
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The main control room serves as a refuge for staff in a nuclear power plant in the event of an accident. To determine whether the control room can meet habitability requirements under accident conditions, this study utilized computational fluid dynamics methods to establish a habitability model of the main control room under such conditions. The changing trends of temperature and velocity near personnel were analyzed. The numerical results indicate that the building envelope significantly contributes to reducing the indoor temperature. The average wall temperature measured at 72 hours was 27?C, with an average temperature increase of 4?C. The highest average ambient temperature in the main control room occurred at 24 hours. At this time, the indoor ambient temperature reached approximately 34.62?C, with a temperature increase of 11.62?C, while the wind speed near the personnel remained below 0.2m/s, meeting habitability requirements for personnel under extreme conditions.
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Agranovski, Igor E., Oleg V. Pyankov, and Igor S. Altman. "Bioaerosol Contamination of Ambient Air as the Result of Opening Envelopes Containing Microbial Materials." Aerosol Science and Technology 39, no. 11 (November 2005): 1048–55. http://dx.doi.org/10.1080/02786820500380230.
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Musorina, Tatiana A., Mikhail R. Petrichenko, Darya D. Zaborova, and Olga S. Gamayunova. "Determination of active and reactive thermal resistance of one-layer building envelopes." Vestnik MGSU, no. 8 (August 2020): 1126–34. http://dx.doi.org/10.22227/1997-0935.2020.8.1126-1134.
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Introduction. The subject of the study is the individual characteristics of a 0.51 m thick external single-layer building envelope made of solid ceramic bricks. The paper focuses on the heat engineering parameters of the wall, namely, the calculation of active and reactive thermal resistances. We determine the differences between the two types of resistances. We also provide an example of calculating the thermal boundary layer in which all temperature fluctuations occur and determining the amount of heat absorbed and released by the envelope.
Materials and methods. We give consideration to taking into account the two components of thermal resistance based on wave functions — thermal and temperature waves. Active thermal resistance is determined at any point of the building envelope with a fixed time value t (stationary heat transfer mode). The coordinate is recorded when determining total resistance. To calculate the thickness of the envelope thermal boundary layer, the temperature differential from −30 to 40 °С outside the premises is considered, the temperature inside the premises is assumed to be 18 °С. The temperature differential value is calculated from the ratio of the difference between current temperatures and the initial value. The required heat quantity and heat output are calculated using standard thermal physics formulas.
Results. The difference between active and reactive thermal resistances, which together make up total thermal resistance, was proved. Active resistance is always 1.57 times less than total resistance. In this case, the active resistance will drop as the temperature differential decreases, and will increase when the outside temperature is higher than the temperature inside the premise. The thermal boundary layer thickness is always less than half of the envelope thickness.
Conclusions. Using this method, it is sufficient to calculate the active thermal resistance of the building envelope to determine the remaining values. In addition, the greater the temperature differential, the thicker the temperature boundary layer, i.e. all temperature changes occur only in this layer while the rest of the envelope functions as a thermal accumulator. When the outside ambient temperature drops, all accumulated heat will be transferred into the premise. Such an envelope can be used to heat the premise or to direct this heat to various envelope elements.
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Anand, Y., A. Gupta, A. Maini, Avi Gupta, A. Sharma, A. Khajuria, S. Gupta, S. Sharma, S. Anand, and S. K. Tyagi. "Comparative Thermal Analysis of Different Cool Roof Materials for Minimizing Building Energy Consumption." Journal of Engineering 2014 (2014): 1–9. http://dx.doi.org/10.1155/2014/685640.
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The roof and walls in the urban areas contribute to major share in the absorption of solar radiations and also retard the outflow of the absorbed radiation from the building envelope, thereby increasing the global warming by inducing the heat island effect. The impact of using cool roof technologies on the thermal comfort of the office buildings has been estimated. Cool roofs reduce electricity consumption for maintaining the temperature of the air-conditioned buildings in the comfort level and also increase comfort in buildings merely not relying completely on cooling equipment. The cool roofs and cool pavements, however, can mitigate summer urban heat islands by improving indoor air quality and comfort. The thermal analysis of different materials has been carried out to analyze the impact of the rate of heat transfer on the building envelope and the results obtained indicate that different cool roof techniques are beneficial in maintaining the comfort level of the building which purely depends on the ambient temperature conditions.
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Busso, Maurizio. "Magnetic and non-magnetic AGB mixing for s-processing." EPJ Web of Conferences 275 (2023): 01005. http://dx.doi.org/10.1051/epjconf/202327501005.
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I outline a few features of recent models for the formation of the neutron source 13C(α,n)16O in low mass stars (1 ≲ M/M⊙ ≲ 3, LMS ) ascendingfor the second time the Red Giant Branch, generally called Asymptotic Giant Branch, or AGB stars. I also briefly outline the nucleosynthesis results obtained trough them. The mentioned models consider the physical structure below the frequent downward extensions of the convective envelope into the He-intershell (the so-called third dredge-up or TDU episodes). There, the conditions are such that the occurrence of further mixing is strongly facilitated, due to the minimal temperature gradient. A way to induce proton mixing from the envelope (certainly not the only one) arises whenever the ambient magnetic fields expected for LMS promote the buoyancy of strongly magnetized flux tubes. I review some characteristics of the ensuing mixing episodes, mentioning how different hydrodynamical processes might yield similar effects, thus encouraging stellar physicists to verify in more detail this possibility.
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Magalhães, A. M., A. C. Carciofi, and D. B. Seriacopi. "Circumstellar Polarimetry." Proceedings of the International Astronomical Union 10, S305 (December 2014): 257–68. http://dx.doi.org/10.1017/s1743921315004871.
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AbstractStarlight polarization provides insight into the physical mechanisms in and around the source as well as its geometry, whether or not the source is resolved. In this talk we will review mechanisms that polarize light in stellar envelopes. The observations and modeling can be used to probe the physics of the circumstellar environment as well as its relation to the ambient interstellar environment.
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Kompatscher, Karin, Rick P. Kramer, Bart Ankersmit, and Henk L. Schellen. "Indoor Airflow Distribution in Repository Design: Experimental and Numerical Microclimate Analysis of an Archive." Buildings 11, no. 4 (April 5, 2021): 152. http://dx.doi.org/10.3390/buildings11040152.
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The majority of cultural heritage is stored in archives, libraries and museum storage spaces. To reduce degradation risks, many archives adopt the use of archival boxes, among other means, to provide the necessary climate control and comply with strict legislation requirements regarding temperature and relative air humidity. A strict ambient indoor climate is assumed to provide adequate environmental conditions near objects. Guidelines and legislation provide requirements for ambient indoor climate parameters, but often do not consider other factors that influence the near-object environment, such as the use of archival boxes, airflow distribution and archival rack placement. This study aimed to provide more insight into the relation between the ambient indoor conditions in repositories and the hygrothermal conditions surrounding the collection. Comprehensive measurements were performed in a case study archive to collect ambient, local and near-object conditions. Both measurements and computational fluid dynamics (CFD) modeling were used to research temperature/relative humidity gradients and airflow distribution with a changing rack orientation, climate control strategy and supply as well as exhaust set-up in a repository. The following conclusions are presented: (i) supplying air from one air handling unit to multiple repositories on different floors leads to small temperature differences between them. Differences in ambient and local climates are noticed; (ii) archival boxes mute and delay variations in ambient conditions as expected—however, thermal radiation from the building envelope may have a large influence on the climate conditions in a box; (iii) adopting night reduction for energy conservation results in an increased influence of the external climate, with adequate insulation, this effect should be mitigated; and (iv) the specific locations of the supply air and extraction of air resulted in a vertical gradient of temperature and insufficient mixing of air, and adequate ventilation strategies should enhance sufficient air mixing in combination with the insulation of external walls, and gradient forming should be reduced.
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Zhang, Zhen-dong, Mamdoh Alajami, and Tariq Alkhalifah. "Wave-equation dispersion spectrum inversion for near-surface characterization using fibre-optics acquisition." Geophysical Journal International 222, no. 2 (May 1, 2020): 907–18. http://dx.doi.org/10.1093/gji/ggaa211.
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SUMMARY Distributed acoustic sensing (DAS) acquisition is becoming more and more popular for its dense sampling at a lower cost than seismometers. However, data processing for DAS data is challenging, especially for surface-deployedfibers, in which only the horizontal component of strain variation is effectively recorded. Also, the coupling between the fiber and the Earth is usually poor and the recorded single-component data are noisy. Thus, we introduce data processing strategies dedicated to enhancing the ambient-noise and active-source seismic data recorded by a horizontally deployed tactical fiber-optics cable buried in a sand dune area in Saudi Arabia. We propose a similarity-weighted stacking of randomly selected short-time duration windows to generate virtual common shot gathers (CSG) from the recorded ambient noise. The similarity-weighted stacking only counts the primary contributions of coherent events, while a short-time correlation can suppress the crosstalk usually present in late arrivals. The stacking fold is preserved or even can be increased by generating plenty of random time segments compared to stacking the full recording time. For the recorded active-source data, we skip the interferometric step, but use the envelope of the CSG. The envelope is needed to mitigate the complexity of waveforms, while preserving the slopes of arrivals. Then, we use the wave-equation-based Rayleigh-wave dispersion spectrum inversion, which utilizes all the dispersion modes available and does not require picking the dispersion curve, in estimating the shallow S-wave velocities. The local cross-correlation objective function allows for additional freedom in matching the modelled and observed data, and thus, helps us avoid falling into a local minimum when starting with kinematically poor velocity models.
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Chamandy, Luke, Eric G. Blackman, Adam Frank, Jonathan Carroll-Nellenback, and Yisheng Tu. "Common envelope evolution on the asymptotic giant branch: unbinding within a decade?" Monthly Notices of the Royal Astronomical Society 495, no. 4 (May 8, 2020): 4028–39. http://dx.doi.org/10.1093/mnras/staa1273.
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ABSTRACT Common envelope (CE) evolution is a critical but still poorly understood progenitor phase of many high-energy astrophysical phenomena. Although 3D global hydrodynamic CE simulations have become more common in recent years, those involving an asymptotic giant branch (AGB) primary are scarce, due to the high computational cost from the larger dynamical range compared to red giant branch (RGB) primaries. But CE evolution with AGB progenitors is desirable to simulate because such events are the likely progenitors of most bi-polar planetary nebulae (PNe), and prominent observational testing grounds for CE physics. Here we present a high-resolution global simulation of CE evolution involving an AGB primary and 1-$\mathrm{M_\odot }$ secondary, evolved for 20 orbital revolutions. During the last 16 of these orbits, the envelope unbinds at an almost constant rate of about 0.1–$0.2\, \mathrm{M_\odot \, yr^{-1}}$. If this rate were maintained, the envelope would be unbound in less than $10\, {\rm yr}$. The dominant source of this unbinding is consistent with inspiral; we assess the influence of the ambient medium to be subdominant. We compare this run with a previous run that used an RGB phase primary evolved from the same 2-$\mathrm{M_\odot }$ main-sequence star to assess the influence of the evolutionary state of the primary. When scaled appropriately, the two runs are quite similar, but with some important differences.
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Chen, Xinxin, and Shuli Sun. "Resonance Detection Method and Realization of Bearing Fault Signal Based on Kalman Filter and Spectrum Analysis." Applied Sciences 13, no. 3 (January 22, 2023): 1472. http://dx.doi.org/10.3390/app13031472.
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The rolling bearing is an important part of mechanical equipment, and its performance significantly affects the quality and life of the mechanical equipment. This article uses the integrated fiber Bragg grating resonant structure sensor excited by periodic micro-shocks caused by micro faults to realize the extraction of information relating to potential faults. Because the fault signal is weak and can easily be interfered with by ambient noise, in order to extract the effective signal, this article determines the autoregressive model of bearing vibration by the final prediction error criterion and the recursive least squares estimation algorithm. The augmented state space model is established based on the autoregressive model. A Kalman filter is used to reduce the noise interference, and then the reduction noisy signal is analyzed by power spectrum and improved autocorrelation envelope spectrum to realize the detection of bearing faults. Through data analysis and method comparison, the proposed improved autocorrelation envelope spectrum analysis can directly extract the bearing fault frequency, which is superior to other methods such as cepstral analysis.
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Tu, Qiang, Fei Yuan, Weidi Yang, and En Cheng. "An Approach for Diver Passive Detection Based on the Established Model of Breathing Sound Emission." Journal of Marine Science and Engineering 8, no. 1 (January 15, 2020): 44. http://dx.doi.org/10.3390/jmse8010044.
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Diver breathing sounds can be used as a characteristic for the passive detection of divers. This work introduces an approach for detecting the presence of a diver based on diver breathing sounds signals. An underwater channel model for passive diver detection is built to evaluate the impacts of acoustic energy transmission loss and ambient noise interference. The noise components of the observed signals are suppressed by spectral subtraction based on block-based threshold theory and smooth minimal statistic noise tracking theory. Then the envelope spectrum features of the denoised signal are extracted for diver detection. The performance of the proposed detection method is demonstrated through experimental analysis and numerical modeling.
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Sanders, Nicholas J., and Alan I. Barreca. "Adaptation to Environmental Change: Agriculture and the Unexpected Incidence of the Acid Rain Program." American Economic Journal: Economic Policy 14, no. 1 (February 1, 2022): 373–401. http://dx.doi.org/10.1257/pol.20190060.
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The Acid Rain Program (ARP) cut sulfur dioxide (SO2) emissions from power plants in the United States, with considerable benefits. We show this also reduced ambient sulfate levels, which lowered agriculture productivity through decreased soil sulfur. Using plant-level SO2 emissions and an atmospheric transport model, we estimate the relationship between airborne sulfate levels and yields for corn and soybeans. We estimate crop revenue losses for these two crops at around $1–$1.5 billion per year, with accompanying decreases in land value. Back-of-the-envelope calculations of the costs to replace lost sulfur suggest producer responses were limited and suboptimal. (JEL Q15, Q24, Q53, Q58)
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Wild, Peter, Claudia Senn, Céline L. Manera, Esther Sutter, Elisabeth M. Schraner, Kurt Tobler, Mathias Ackermann, Urs Ziegler, Miriam S. Lucas, and Andres Kaech. "Exploring the Nuclear Envelope of Herpes Simplex Virus 1-Infected Cells by High-Resolution Microscopy." Journal of Virology 83, no. 1 (October 15, 2008): 408–19. http://dx.doi.org/10.1128/jvi.01568-08.
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ABSTRACT Herpesviruses are composed of capsid, tegument, and envelope. Capsids assemble in the nucleus and exit the nucleus by budding at the inner nuclear membrane, acquiring tegument and the envelope. This study focuses on the changes of the nuclear envelope during herpes simplex virus 1 (HSV-1) infection in HeLa and Vero cells by employing preparation techniques at ambient and low temperatures for high-resolution scanning and transmission electron microscopy and confocal laser scanning microscopy. Cryo-field emission scanning electron microscopy of freeze-fractured cells showed for the first time budding of capsids at the nuclear envelope at the third dimension with high activity at 10 h and low activity at 15 h of incubation. The mean number of pores was significantly lower, and the mean interpore distance and the mean interpore area were significantly larger than those for mock-infected cells 15 h after inoculation. Forty-five percent of nuclear pores in HSV-1-infected cells were dilated to more than 140 nm. Nuclear material containing capsids protrude through them into the cytoplasm. Examination of in situ preparations after dry fracturing revealed significant enlargements of the nuclear pore diameter and of the nuclear pore central channel in HSV-1-infected cells compared to mock-infected cells. The demonstration of nucleoporins by confocal microscopy also revealed fewer pores but focal enhancement of fluorescence signals in HSV-1-infected cells, whereas Western blots showed no loss of nucleoporins from cells. The data suggest that infection with HSV-1 alters the number, size, and architecture of nuclear pores without a loss of nucleoporins from altered nuclear pore complexes.
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Dwarkadas, Vikram V., Roger A. Chevalier, and John M. Blondin. "Effect of ambient wind velocity on Planetary Nebula morphology." Symposium - International Astronomical Union 180 (1997): 224. http://dx.doi.org/10.1017/s0074180900130451.
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Planetary Nebulae (PNe) are formed by the interaction of the fast wind from a post-Asymptotic Giant Branch Star with the slow ambient wind from a previous epoch. If the two interacting winds have constant properties, the velocity of the PN shell tends towards a constant with time and the shape becomes self-similar. Additionally, if the velocity of the fast wind is much higher than the expansion velocity of the shell, the interior of the hot shocked bubble becomes isobaric. Using semi-analytical methods, complemented by hydrodynamic simulations, we have calculated the shapes of PNe in the self-similar stage (Dwarkadas et al. 1996). We have investigated the contribution of the ambient wind velocity to PN morphology, which has hitherto not received much attention since the work of Kahn & West (1985). We find that the nebular morphology is a consequence of the density contrast between pole and equator in the ambient medium, the steepness of the density profile and the velocity of the ambient wind; classification of PNe purely on the basis of the first two factors may be misleading. In particular, the ratio of ambient wind velocity to PN velocity is important in determining whether the nebula shows a bulge or a cusp at the equator. A high density contrast coupled with a low velocity for the external medium gives rise to extremely bipolar nebulae. For large density contrasts and a significant value of the slow wind velocity, the surface density maximum of the shell shifts away from the equator, giving rise to peanut-shaped structures with pronounced equatorial bulges. As long as the external wind velocity is small compared to the expansion velocity of the nebula, the PNe tend to be more bipolar, even with a moderate density contrast. If the PN velocity is close to that of the external wind, the shape is relatively spherical. However, inclusion of an asymmetric velocity profile in the slow wind, with the velocity increasing towards the pole, can lead to a bipolar nebula if the equatorial velocity is sufficiently low. Preliminary results with a slow wind velocity increasing towards the equator (as is found in calculations of common envelope evolution) show that the nebulae tend to be more oblate, which is not often observed in nature. Representative results for shapes of PNe using various values of the relevant parameters are presented.
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Maureira, María José, Héctor G. Arce, Michael M. Dunham, Diego Mardones, Andrés E. Guzmán, Jaime E. Pineda, and Tyler L. Bourke. "ALMA observations of envelopes around first hydrostatic core candidates." Monthly Notices of the Royal Astronomical Society 499, no. 3 (September 24, 2020): 4394–417. http://dx.doi.org/10.1093/mnras/staa2894.
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ABSTRACT We present ALMA 3 mm molecular line and continuum observations with a resolution of ∼3.5 arcsec towards five first hydrostatic core (FHSC) candidates (L1451-mm, Per-bolo 58, Per-bolo 45, L1448-IRS2E, and Cha-MMS1). Our goal is to characterize their envelopes and identify the most promising sources that could be bona fide FHSCs. We identify two candidates that are consistent with an extremely young evolutionary state (L1451-mm and Cha-MMS1), with L1451-mm being the most promising FHSC candidate. Although our envelope observations cannot rule out Cha-MMS1 as an FHSC yet, the properties of its CO outflow and SED published in recent studies are in better agreement with the predictions for a young protostar. For the remaining three sources, our observations favour a pre-stellar nature for Per-bolo 45 and rule out the rest as FHSC candidates. Per-bolo 58 is fully consistent with being a Class 0, while L1448 IRS2E shows no emission of high-density tracers (NH2D and N2H+) at the location of the previously identified compact continuum source, which is also undetected in our observations. Thus, we argue that there is no embedded source at the presumptive location of the FHSC candidate L1448 IRS2E. We propose instead that what was thought to be emission from the presumed L1448 IRS2E outflow corresponds to outflow emission from a nearby Class 0 system, deflected by the dense ambient material. We compare the properties of the FHSC candidates studied in this work and the literature, which shows that L1451-mm appears as possibly the youngest source with a confirmed outflow.
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Dzieran, L., M. Thorwart, and W. Rabbel. "Seismoelectric monitoring of aquifers using local seismicity—a feasibility study." Geophysical Journal International 222, no. 2 (April 30, 2020): 874–92. http://dx.doi.org/10.1093/gji/ggaa206.
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SUMMARY Seismoelectric (SE) signals, accompanying seismic wave fields radiated from earthquakes, can be observed on records of magnetotelluric stations. Assuming that these SE signals are generated by electrokinetic coupling we investigate whether they can be used as a ‘pore-space monitoring’-tool. Regarding future field experiments we analyse synthetic SE waveforms calculated for a fully saturated base model consisting of five layers overlying a half-space, resembling the conditions of the Armutlu Peninsula (Turkey). This example site stands for a location with near-surface thermal aquifers exposed to tectonic stress and significant microseismicity. As expected, coseismic SE waves arrive simultaneously with the seismic onsets whereas interface response (IRs) SE waves arrive (shortly) before the generating seismic onsets. Therein, so-called evanescent IRs show a similar moveout as seismic phases and so-called radiation IRs travel with zero slowness. We found that the influence of IRs on the overall SE signal can be identified by envelope analysis of SE time series and by seismoelectric spectral ratios (SESRs) in the frequency domain. For a sensitivity analysis we added an extra layer to the base model with differing porosity, porefluid salinity and permeability values. At near-epicentral distances both trace-envelopes and SESRs are sensitive to the porosity and porefluid salinity changes in the simulated near-surface aquifer. The SESRs’ and SE envelopes’ amplitudes vary in the order of up to some 10 per cent in response to porosity and salinity increases of factor 2 and 100, respectively. In contrast, a decrease of the permeability value by the factor 100 leads to an SESR amplitude variation of less than 1–10 per cent. In the Armutlu model the largest relative changes of SE signals occur near the epicentre where the ratio between coseismic and IR amplitudes is close to 1. For 1–6 km deep source depth the SE detection swell at the earth surface is in the order of magnitude 2–3, depending on the ambient electromagnetic noise and hypocentral distance. This estimate assumes that SE signals are recorded with standard magnetotelluric stations. It can improve if array methods are applied.
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Ai 艾, Tsung-Han 宗瀚, Chun-Fan 君帆 Liu 劉, Hsien 賢. Shang 尚, Doug Johnstone, and Ruben Krasnopolsky. "A Unified Model for Bipolar Outflows from Young Stars: Kinematic and Mixing Structures in HH 30." Astrophysical Journal 964, no. 2 (March 27, 2024): 147. http://dx.doi.org/10.3847/1538-4357/ad2355.
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Abstract The young stellar source HH 30 is a textbook example of an ionic optical jet originating from a disk in an edge-on system shown by the Hubble Space Telescope. It has a remnant envelope in 12CO observed by the Atacama Large Millimeter/submillimeter Array. The optical jet is characterized by its narrow appearance, large line width at the base, and high temperature inferred from line diagnostics. Three featured structures can be identified, most evident in the transverse position–velocity diagrams: an extremely-high-velocity wide-angle wind component with large spectral widths in the optical, a very-low-velocity ambient surrounding medium seen in 12CO, and a low-velocity region traced by 12CO nested both in velocity and location between the primary wind and ambient environment. A layered cavity with multiple shells forms nested morphological and kinematic structures around the optical jet. The atomic gas originating from the innermost region of the disk attains a sufficient temperature and ionization to emit brightly in forbidden lines as an optical jet. The wide-angle portion expands, forming a low-density cavity. The filamentary 12CO encompassing the wind cavity is mixed and advected inward through the action of the magnetic interplay of the wide-angle wind with the molecular ambient medium. The magnetic interplay results in the layered shells penetrating deeply into the vast cavity of tenuous atomic wind material. The HH 30 system is an ideal manifestation of the unified wind model of Shang et al. (2020, 2023), with clearly distinguishable atomic and molecular species mixed through the atomic lightly ionized magnetized wind and the surrounding cold molecular ambient material.
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Demirci, Tunahan, and Gerhard Wurm. "Accretion of eroding pebbles and planetesimals in planetary envelopes." Astronomy & Astrophysics 641 (September 2020): A99. http://dx.doi.org/10.1051/0004-6361/202038690.
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Wind erosion is a destructive mechanism that completely dissolves a weakly bound object like a planetesimal into its constituent particles, if the velocity relative to the ambient gas and the local gas pressure are sufficiently high. In numerical simulations we study the influence of such wind erosion on pebble and planetesimal accretion by a planetary body up to 10 REarth. Due to the rapid size reduction of an in-falling small body, the accretion outcome changes significantly. Erosion leads to a strong decrease in the accretion efficiency below a threshold size of the small body on the order of 10 m. This slows down pebble accretion significantly for a given size distribution of small bodies. The threshold radius of the small body increases with increasing planet radius and decreases with increasing semi-major axis. Within the parameters studied, an additional planetary atmosphere (up to 1 bar) is of minor importance.
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Tsai, Bor Jang, Koo David Huang, and Chien Ho Lee. "Hybrid Structural Systems of An Active Building Envelope System(ABE)." Advanced Materials Research 168-170 (December 2010): 2359–70. http://dx.doi.org/10.4028/www.scientific.net/amr.168-170.2359.
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This study takes the ventilation into consideration, making the active building envelope (ABE) system more close to the realistic application conditions. The ABE system is comprised of a photovoltaic unit (PV unit) and a thermoelectric heat pump unit (TE unit). The PV unit consists of photovoltaic cells, which convert solar radiation energy into electrical energy. The TE unit consists of thermoelectric heaters/coolers (referred to here onwards as TE coolers), which convert electrical energy into thermal energy, or the reverse. The PV and the TE units are integrated within the overall ABE enclosure. The new mechanism of a hybrid system was proposed. A ducted wind turine will be integrated with the ABE system becoming dual core. Then the analytic model of original ABE system has to be revised and analytic solution will be resulted and verified by the numerical solution of CFD. The ducted wind mill will provide air conditioning and power the ABE system, to higher the thermal efficiency of the heat sinks of TE system. Numerical and experimental works will be investigated. a building installed the ABE system wind, solar driven, bypass the windmill flow as a air flow, ambient temperature, To is equal to 35 oC and indoor temperature, Ti is 28 oC. Numerical results show the Ti will decrease 2 oC when the ABE operating with heat sinks, without fan. As fan is opened, strong convective heat transfer, Ti will decrease approximately 4 to 5 oC. We hope findings of this study can make the dream of healthy living comfortable room come true.
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Hoffer, András, Aida Meiramova, Ádám Tóth, Beatrix Jancsek-Turóczi, Gyula Kiss, Ágnes Rostási, Erika Andrea Levei, Luminita Marmureanu, Attila Machon, and András Gelencsér. "Assessment of the contribution of residential waste burning to ambient PM10 concentrations in Hungary and Romania." Atmospheric Chemistry and Physics 24, no. 3 (February 6, 2024): 1659–71. http://dx.doi.org/10.5194/acp-24-1659-2024.
Full textAbstract:
Abstract. The illegal burning of solid waste in residential stoves is an existing practice, but until now it has been completely disregarded as an emission source of atmospheric pollutants in many developed countries, including those in eastern Europe. Various types of solid waste (plastics, treated wood, plyboards, tyre, rag) serve as an auxiliary fuel in many households, in particular during the heating season. In this work, for the first time ever in atmospheric pollution studies, specific tracer compounds identified previously in controlled test burnings of different waste types in the laboratory were detected and quantified in ambient PM10 samples collected in five Hungarian and four Romanian settlements. Using the identified tracers and their experimentally determined relative emission factors, the potential contribution of illegal waste burning emissions to ambient PM10 mass concentrations was assessed. Our findings implied that the burning of polyethylene terephthalate (PET)-containing waste (food and beverage packaging, clothes) was predominant at all the locations, especially in north-eastern Hungary and Romania. There is substantial evidence that the burning of scrap furniture is also common in big cities in Hungary and Romania. Back-of-the-envelope calculations based on the relative emission factors of individual tracers suggested that the contribution of solid waste burning particulate emissions to ambient PM10 mass concentrations may be as high as a few percent. This finding, when considering the extreme health hazards associated with particulate emissions from waste burning, is a matter of serious public health concern.
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Wagner, Karl. "Adaption of a tropical passive house as holistic approach." South Florida Journal of Development 3, no. 3 (June 7, 2022): 3755–72. http://dx.doi.org/10.46932/sfjdv3n3-056.
Full textAbstract:
Several attempts have been made in tropical countries to conduct green mock-up research on which parameters can better withstand the heat and humidity: Walls, windows, roofs, and even shadings have been tested in mainly so-called contrived experiments. The challenge of a tropical "holistic" Passive building is to bring ALL those relevant parameters into play in different seasonal and weather situations whilst expelling the interference of the hot outside air. In principle, this is happening anyway for most commercial buildings and Passive Houses in all other hemispheres alike, but it is not common for tropical residential building strategies. The author refers back to a database of 250 days from a suburban area in Malaysia. Data out of 4 typically hot months in the year 2017 in detail with 3 adjacent real mini-residential Passive and 1 "red" House(s) with the same positioning for ambient temperature and the most vulnerable part of the building envelope which is the window were cross-examined. The well insulated, basically almost airtight and optimum shaded building with ventilation performed cooler in almost all cases during the rainy season and the increasing number of transition periods. Without aircon and due to the lack of a moisture barrier it remained humid, but with no harm for occupants and the building envelope. The Passive holistic design will work best i.e. energy efficiently in a combination of a) nighttime active usage of green cooling (i.e. cross ventilation or water-based cooling ceilings). During b) daytime, among other related modules looked in, cooling is based upon passive envelope features PLUS shading. For various reasons, compared to buildings in the colder hemisphere (such as tropical thin building envelope and no triple glazing required), the payback of the Tropical Mass Residential Passive House comparing OPEX and CAPEX is reasonable with 5-6 years.