Control of Cavity-Induced Drag Using Steady Jets

Separated shear layer oscillations in open cavities can induce drag, noise and vibration. This issue has many aerospace applications such as Landing gears and control surfaces [1]. Recently, phase-cancellation [1] and offinstability frequency excitation [2] & [3] approaches have been incorporated in different open-loop and feedback control systems. Despite the high control performance of these systems, further enhancement is still possible. In this study, steady jets, as shown in fig. 1, are forced through 2mm, two-dimensional slots at the leading and trailing edges of the cavity. In order to study the performance of this novel approach, different cases will be examined, including: jet combination (blowing from cavity leading edge, suction from cavity leading edge and blowing-suction), jet angle (parallel or deflected jet) and jet-to-free stream velocity factor /.

Control of Cavity-Induced Drag Using Steady Jets

Separated shear layer oscillations in open cavities can induce drag, noise and vibration. This issue has many aerospace applications such as Landing gears and control surfaces [1]. Recently, phase-cancellation [1] and offinstability frequency excitation [2] & [3] approaches have been incorporated in different open-loop and feedback control systems. Despite the high control performance of these systems, further enhancement is still possible. In this study, steady jets, as shown in fig. 1, are forced through 2mm, two-dimensional slots at the leading and trailing edges of the cavity. In order to study the performance of this novel approach, different cases will be examined, including: jet combination (blowing from cavity leading edge, suction from cavity leading edge and blowing-suction), jet angle (parallel or deflected jet) and jet-to-free stream velocity factor /.

Call and Response: SEM President’s Roundtable 2016, “Ethnomusicological Responses to the Contemporary Dynamics of Migrants and Refugees”

The privilege of organizing the SEM President’s Roundtable in 2016 and 2017 provided an opportunity to call attention to a topic that has concerned my teaching and research since graduate school. For the first iteration of “Ethnomusicological Responses to the Contemporary Dynamics of Migrants and Refugees” I convened a panel of people whose perspectives I admire. I wanted to learn from them, and I did. As someone who has been involved with Middle Eastern and more specifically Arab music and culture within my own academic and regional community, I was making new efforts in the fall of 2016 toward engaged ethnomusicology in Virginia among my own newest neighbors, and organizing this SEM President’s Roundtable gave me courage and inspiration. Our “Call and Response” presents snapshots from five colleagues who are engaged with communities of migrants and refugees in Africa, the Middle East, Europe, and North America..

N=2 superparticle near horizon of extreme Kerr-Newman-AdS-dS black hole

Conformal mechanics related to the near horizon extreme Kerr-Newman-AdS-dS black hole is studied. A unique N=2 supersymmetric extension of the conformal mechanics is constructed.Comment: V2: the version to appear in NP

Second extracellular loop of human glucagon-like peptide-1 receptor (GLP-1R) differentially regulates orthosteric but not allosteric agonist binding and function

The glucagon-like peptide-1 receptor (GLP-1R) is a prototypical family B G protein-coupled receptor that exhibits physiologically important pleiotropic coupling and ligand-dependent signal bias. In our accompanying article (Koole, C., Wootten, D., Simms, J., Miller, L. J., Christopoulos, A., and Sexton, P. M. (2012) J. Biol. Chem. 287, 3642-3658), we demonstrate, through alanine-scanning mutagenesis, a key role for extracellular loop (ECL) 2 of the receptor in propagating activation transition mediated by GLP-1 peptides that occurs in a peptide- and pathway-dependent manner for cAMP formation, intracellular (Ca 2+ i) mobilization, and phosphorylation of extracellular signal-regulated kinases 1 and 2 (pERK1/2). In this study, we examine the effect of ECL2 mutations on the binding and signaling of the peptide mimetics, exendin-4 and oxyntomodulin, as well as small molecule allosteric agonist 6,7-dichloro-2-methylsulfonyl-3-tert-butylaminoquinoxaline (compound 2). Lys-288, Cys-296, Trp-297, and Asn-300 were globally important for peptide signaling and also had critical roles in governing signal bias of the receptor. Peptide-specific effects on relative efficacy and signal bias were most commonly observed for residues 301-305, although R299A mutation also caused significantly different effects for individual peptides. Met-303 was more important for exendin-4 and oxyntomodulin action than those of GLP-1 peptides. Globally, ECL2 mutation was more detrimental to exendin-4-mediated Ca 2+ i release than GLP-1(7-36)-NH 2, providing additional evidence for subtle differences in receptor activation by these two peptides. Unlike peptide activation of the GLP-1R, ECL2 mutations had only limited impact on compound 2 mediated cAMP and pERK responses, consistent with this ligand having a distinct mechanism for receptor activation. These data suggest a critical role of ECL2 of the GLP-1R in the activation transition of the receptor by peptide agonists

Researchers and Social Networking Sites usage: the application of UTAUT theory

Purpose (limit 100 words) This study aims to investigate the use of SNS by researchers and their behaviours when conducting research-related activities by applying the UTAUT theory Design/methodology/approach (limit 100 words) An online survey was distributed. This study's design is derived from the UTAUT framework's questionnaire items. The sample of this study comprised 216 respondents from 40 universities in the United Kingdom. Descriptive statistics were used to analyse the data. Findings (limit 100 words) Respondents revealed a positive relationship between the four constructs of the UTAUT framework (performance expectancy, effort expectancy, social influence, and facilitating condition) associated with their intention to use SNS. Research limitations/implications (limit 100 words) Most of the respondents were from the University of Strathclyde, so we cannot generalize the findings to other universities. Practical implications (limit 100 words) The findings will offer an extensive understanding of the value of social networking sites, which will aid researchers to increase their visibility, and research activities online. Originality/value (limit 100 words) The results will provide an in-depth knowledge of the importance of social networking sites, helping scholars to become more visible and engage in online research. A number of factors impacted how researchers behaved on social networking sites and what they intended to use for research-related activity. School administrators, experts, and other sponsors could take action to promote the use of social networking sites (SNSs) in educational settings based on the findings. The study's findings offer insightful knowledge to those who create SNS websites. By using this information, they will be able to improve these sites for research and study and gain a better understanding of the demands of SNS users

Optimal Configuration and Sizing of Seaport Microgrids including Renewable Energy and Cold Ironing—The Port of Aalborg Case Study

Microgrids are among the promising green transition technologies that will provide enormous benefits to the seaports to manage major concerns over energy crises, environmental challenges, and economic issues. However, creating a good design for the seaport microgrid is a challenging task, considering different objectives, constraints, and uncertainties involved. To ensure the optimal operation of the system, determining the right microgrid configuration and component size at minimum cost is a vital decision at the design stage. This paper aims to design a hybrid system for a seaport microgrid with optimally sized components. The selected case study is the Port of Aalborg, Denmark. The proposed grid-connected structure consists of renewable energy sources (photovoltaic system and wind turbines), an energy storage system, and cold ironing facilities. The seaport architecture is then optimized by utilizing HOMER to meet the maximum load demand by considering important parameters such as solar global horizontal irradiance, temperature, and wind resources. Finally, the best configuration is analyzed in terms of economic feasibility, energy reliability, and environmental impacts