270 research outputs found
Thermal analysis, optimization and design of a Martian oxygen production plant
The objective is to optimally design the thermal components of a system that uses carbon dioxide (CO2) from the Martian atmosphere to produce oxygen (O2) for spacecraft propulsion and/or life-support. Carbon dioxide is thermally decomposed into carbon monoxide (CO) and O2 followed by the electrochemical separation of O2. The design of the overall system and its various individual components depends on, among other things, the fraction of the stoichiometric yield of O2 that can be realized in the system and the temperature of operation of the electrochemical separation membrane. The analysis indicates that a substantial reduction could be obtained in the mass and power requirements of the system if the unreacted CO2 were to be recycled. The concepts of an optimum temperature of the zirconia cell and impracticality of plant operation at low cell efficiencies are also discussed. The design of the thermal equipment is such that the mass and power requirements of the individual components and of the overall system are optimized
Recommended from our members
R -parity violation in a warped GUT scale Randall-Sundrum framework
© 2016 American Physical Society. We consider a modified Randall-Sundrum (RS) framework between the Planck scale and the grand unified theory (GUT) scale. In this scenario, RS works as a theory of flavor and not as a solution to the hierarchy problem. The latter is resolved by supersymmetrizing the bulk, so that the minimal supersymmetric standard model is the effective four-dimensional theory. Matter fields are localized in the bulk in order to fit fermion-mass and mixing data. If R-parity violating (Rp) terms are allowed in the superpotential, their orders of magnitude throughout flavor space are then predicted, resulting in rich flavor textures. If the Rp contributions to neutrino masses are somewhat suppressed, then lepton-number violating models exist which explain the neutrino oscillation data while not being in contradiction with current experimental bounds. Another promising model is one where baryon number is violated and Dirac neutrino masses result solely from fermion localization. We sketch the likely discovery signatures of the baryon-number and the lepton-number violating cases.This work was partially supported by STFC grant ST/L000385/1. BCA was adjunct faculty in DTP TIFR during December 2014 and would like to thank the department for the hospitality extended during the early stages of this work and the Cambridge SUSY Working Group for helpful suggestions. BCA, AI and KS would like to thank Sudhir Vempati for the motivation and useful discussions. AI and KS also thank the organisers at WHEPP 2013 for the hospitality where the idea was conceived. AI and KS would also like to thank the CERN theory division for hospitality where part of the work was completed. AI would like to thank Tuhin Roy for discussions on contribution to renormalization of soft masses due to hidden sector effects
Kaluza–Klein gluon + jets associated production at the Large Hadron Collider
AbstractThe Kaluza–Klein excitations of gluons offer the exciting possibility of probing bulk Randall–Sundrum (RS) models. In these bulk models either a custodial symmetry or a deformation of the metric away from AdS is invoked in order to deal with electroweak precision tests. Addressing both these models, we suggest a new channel in which to study the production of KK-gluons (gKK): one where it is produced in association with one or more hard jets. The cross-section for the gKK + jets channel is significant because of several contributing sub-processes. In particular, the 1-jet and the 2-jet associated processes are important because at these orders in QCD the qg and the gg initial states respectively come into play. We have performed a hadron-level simulation of the signal and present strategies to effectively extract the signal from what could potentially be a huge background. We present results for the kinematic reach of the LHC Run-II for different gKK masses in bulk-RS models
TinyML: Tools, Applications, Challenges, and Future Research Directions
In recent years, Artificial Intelligence (AI) and Machine learning (ML) have
gained significant interest from both, industry and academia. Notably,
conventional ML techniques require enormous amounts of power to meet the
desired accuracy, which has limited their use mainly to high-capability devices
such as network nodes. However, with many advancements in technologies such as
the Internet of Things (IoT) and edge computing, it is desirable to incorporate
ML techniques into resource-constrained embedded devices for distributed and
ubiquitous intelligence. This has motivated the emergence of the TinyML
paradigm which is an embedded ML technique that enables ML applications on
multiple cheap, resource- and power-constrained devices. However, during this
transition towards appropriate implementation of the TinyML technology,
multiple challenges such as processing capacity optimization, improved
reliability, and maintenance of learning models' accuracy require timely
solutions. In this article, various avenues available for TinyML implementation
are reviewed. Firstly, a background of TinyML is provided, followed by detailed
discussions on various tools supporting TinyML. Then, state-of-art applications
of TinyML using advanced technologies are detailed. Lastly, various research
challenges and future directions are identified.Comment: 12 pags, 3 tables, 4 figure
Middleware Architecture - History and Adaptation with IEEE 802.11
Communication, which intends to provide a link between any two people, is now moving towards man-to-machine and machine-to-machine connection for transferring different types of data. This transmission scenario, with and ever expanding number of active and passive users, lays the foundation to variety of communication protocols owing to the different types of data which is involved in the process. Within this ever expanding communication arena, Middle-ware can be thought of as a set of hardware and software which is used to connect different platforms with the end-users that are increasing in number day-by-day, with a possible wide spread over any region spanning from few meters to several kilometers. IEEE 802.11 is the set of standards which guides the wireless technology for device implementation and demands seamless integration across the entire protocol stack. This in turn demands an overview of the middleware architecture in broader perspective. This chapter explores the concept of middleware in the existing communication scenario, current trends and future scope
A Framework of Exercise Recommendation for Novice Learners in Computer Programming
To support novice learners majoring in Information Technology, this paper proposed an ontology-based framework to recommend exercise to learners in response to their understanding levels. This framework involves three essential mechanisms: (1) determination of the level of exercise, (2) evaluation of learner's understanding, and (3) recommendation of exercise. The prototype system will be implemented to enable the instructors to add or edit exercises based on 60 questions with solutions covering 20 topics of introductory programming which are initially determined by this research
Recognition of Error Symptoms in Large Systems
Coordinated Science Laboratory was formerly known as Control Systems LaboratoryJoint Services Electronics Program / N00014-84-C-0149IBM Corporatio
- …