1,720,965 research outputs found
Modeling of indoor particulate matter deposition to occupant typical wrinkled shirt surface
Get PDFsponsorship: The authors would like to acknowledge the American University of Beirut (AUB) and the Lebanese National Council for Scientific Research (CNRS-L), Lebanon, for granting a doctoral fellowship to Ms. Douaa Al Assaad. (American University of Beirut (AUB), Lebanese National Council for Scientific Research (CNRS-L), Lebanon)status: Publishe
High-Resolution Indoor Environmental Dataset from a Living Lab with Personalized Environmental Control Systems (PECS)
No full textThe building sector faces growing challenges in balancing energy efficiency with occupant comfort, especially amid climate change, air pollution, and post-pandemic demands on HVAC systems. Personalized Environmental Control Systems (PECS) offer a promising solution by allowing individuals to control their immediate environment (e.g., temperature, air quality), thereby enabling energy savings without sacrificing comfort. Despite their proven benefits, PECS have seen limited market adoption due to the lack of standardized performance evaluation methods and benchmark data.
Computational Fluid Dynamics (CFD) is commonly used to study PECS, but creating accurate CFD models is resource-intensive and requires detailed experimental validation—something many researchers struggle to provide due to limited infrastructure. Currently, only one known benchmark dataset exists, which is not representative of real-world settings.
To address this gap, the current work presents a high-resolution dataset of indoor environmental measurements (air velocity, temperature, and CO₂) from a living lab designed to simulate an open-plan office. The dataset, detailed in an accompanying Excel file, supports the creation and validation of CFD models for spaces equipped with various ventilation setups, including standalone systems and PECS configurations
Evaluation of different personalized ventilation air terminal devices: Inhalation vs. clothing-mediated exposures
Get PDFsponsorship: The authors would like to acknowledge the American University of Beirut (AUB) and the National Council for Scientific Research of Lebanon (CNRS-L) for granting a doctoral fellowship to Ms. Douaa Al Assaad. In addition, this collaborative research was made possible by the award (QUEX-CENG-ASPIRE-11/12-7) from ASPIRE Zone Foundation, Doha, Qatar. (American University of Beirut (AUB), National Council for Scientific Research of Lebanon (CNRS-L), ASPIRE Zone Foundation, Doha, Qatar|QUEX-CENG-ASPIRE-11/12-7)status: Publishe
Performance of Mixing Ventilation System Coupled With Dynamic Personalized Ventilator for Thermal Comfort
No full textThis study optimizes the performance of a mixing ventilation system coupled with a personalized ventilator that emits a cool sinusoidal horizontal airflow jet towards the occupant upper body in order to achieve good overall thermal comfort and good air quality in the occupant breathing zone. A transient 3-D computational fluid dynamics (CFD) model coupled with a transient bio-heat model was deployed to predict airflow and temperature fields in the space and around the occupant as well as segmental skin temperature profiles for local and overall thermal sensation and comfort analysis.
Simulations were performed using the CFD model to determine the airflow optimal supply frequency, mean flow rate and amplitude at room temperature of 25 °C and PV jet temperature of 22 °C. The system also showed, that when increasing frequency at fixed mean flow rate, thermal comfort increased from by 15.2 %. However when increasing mean flow rate at a fixed frequency, thermal comfort dropped at the low frequency of 0.3 Hz but remained acceptable at the higher frequency of 0.5 Hz.</jats:p
Effect of individually controlled personalized ventilation on cross-contamination due to respiratory activities
Get PDFsponsorship: The authors would like to acknowledge the financial support of the Munib and Angela Masri Institute of Energy and Natural Resources at the American University of Beirut grant award 103973. In addition, the American University of Beirut PhD scholarship to Ms. Katramiz is highly acknowledged. The authors would like to also acknowledge the American University of Beirut (AUB) and the National Council for Scientific Research of Lebanon (CNRS-L) for granting a doctoral fellowship to Ms. Douaa Al Assaad. In addition, this collaborative research was made possible by the award [QUEX-CENG-ASPIRE-11/12-7] from ASPIRE Zone Foundation, Doha, Qatar. (Munib and Angela Masri Institute of Energy and Natural Resources at the American University of Beirut|103973, American University of Beirut PhD scholarship, American University of Beirut (AUB), National Council for Scientific Research of Lebanon (CNRS-L), ASPIRE Zone Foundation, Doha, Qatar|QUEX-CENG-ASPIRE-11/12-7)status: Publishe
Evaluation of the spatial aspect of building resilience in classrooms equipped with displacement ventilation
No full textThroughout their lifetime, buildings might face unpredictable shocks leading to fast deterioration of comfort levels. The ability of buildings and systems to absorb the shock and bring back the indoor conditions to their designed state is termed as “resilience”. Ventilation and thermal resilience have been studied under homogeneous conditions. However, the established airflow indoors and hence resilience is non-homogeneous. In this work, the spatial aspect of ventilation and thermal resilience will be assessed in a classroom equipped with displacement ventilation using 3D CFD modeling. Two sources of pollution were considered in the space: CO2 and VOCs. To study resilience, the numerical model was simulated until steady state. Subsequently, a power outage shock of 60 min was induced. The temporal and spatial mappings of temperature, and pollutants’ concentration were recorded in the occupied zone at the breathing height of 1.2 m and compared to that at the exhaust. Building resilience was assessed through ppm.hours and degree.hours and compared at both locations. Results showed that resilience is rather a non-homogeneous field that depends on the location of heat sources and pollution sources in the space. However, results showed that any over or under estimations (~20 − 28%) in assessing the thermal or ventilation resilience are negligible when evaluated at either the breathing plane or the exhaust
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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