45 research outputs found
An Anlysis on Email Classification by Using Topic Modeling
Email Classification is a broad term. It might be used to separate spam email, detect phishing emails, detect threat emails, and many other aspects. Many papers have been published on these topics over the years. This paper is focusing on classifying email into different categories by using the topic modeling technique. For that, the email body will be analyzed to categorize emails from scratch. In topic modeling, documents are considered a collection of topics, and topics are considered a collection of words, also known as a bag of words. We used the Latent Dirichlet Allocation topic model, also known as the LDA topic model to extract topics from email dataset. We used the Enron email dataset for our experiment, which is the largest open-source email dataset. The expected outcome will be human interpretable topics that can easily be identified and categorized by labeling them
Formulation and development of a topical combination cream for arthritis management
Purpose: To design and prepare a non-prescription cream for cost-effective, potent, rapid and longlasting relief from arthritic pain.Method: The cream was prepared by formulating the aqueous phase using glucosamine sulphate, potassium chloride and chondroitin sulphate sodium, and then pouring it into the oil phase under suitable conditions. The physicochemical and antimicrobial properties, in vitro and ex vivo drug release, and overall physical and chemical stability of the formulations were characterized.Results: Sodium metabisulfite (0.5 %) and butylated hydroxyanisole (BHA) (0.01 %) showed a very strong synergistic effect on overall stability of the cream.Conclusion: This study confirms that the formulated cream is potentially suitable for the management of arthritis pain in patients.
Keywords: Arthritis, Ex vivo drug release, Sodium metabisulfite, Butylated hydroxyanisole, Product stabilit
Compact Model of a Topological Transistor
The precession of a ferromagnet leads to the injection of spin current and
heat into an adjacent non-magnetic material. Besides, spin-orbit entanglement
causes an additional charge current injection. Such a device has been recently
proposed where a quantum-spin hall insulator (QSHI) in proximity to a
ferromagnetic insulator (FI) and superconductor (SC) leads to the pumping of
charge, spin, and heat. Here we build a circuit-compatible Verilog-A-based
compact model for the QSHI-FI-SC device capable of generating two topologically
robust modes enabling the device operation. Our model also captures the
dependence on the ferromagnetic precision, drain voltage, and temperature with
an excellent (> 99%) accuracy
Cryogenic Neuromorphic Hardware
The revolution in artificial intelligence (AI) brings up an enormous storage
and data processing requirement. Large power consumption and hardware overhead
have become the main challenges for building next-generation AI hardware. To
mitigate this, Neuromorphic computing has drawn immense attention due to its
excellent capability for data processing with very low power consumption. While
relentless research has been underway for years to minimize the power
consumption in neuromorphic hardware, we are still a long way off from reaching
the energy efficiency of the human brain. Furthermore, design complexity and
process variation hinder the large-scale implementation of current neuromorphic
platforms. Recently, the concept of implementing neuromorphic computing systems
in cryogenic temperature has garnered intense interest thanks to their
excellent speed and power metric. Several cryogenic devices can be engineered
to work as neuromorphic primitives with ultra-low demand for power. Here we
comprehensively review the cryogenic neuromorphic hardware. We classify the
existing cryogenic neuromorphic hardware into several hierarchical categories
and sketch a comparative analysis based on key performance metrics. Our
analysis concisely describes the operation of the associated circuit topology
and outlines the advantages and challenges encountered by the state-of-the-art
technology platforms. Finally, we provide insights to circumvent these
challenges for the future progression of research
Cryogenic Memory Technologies
The surging interest in quantum computing, space electronics, and
superconducting circuits has led to new developments in cryogenic data storage
technology. Quantum computers promise to far extend our processing capabilities
and may allow solving currently intractable computational challenges. Even with
the advent of the quantum computing era, ultra-fast and energy-efficient
classical computing systems are still in high demand. One of the classical
platforms that can achieve this dream combination is superconducting single
flux quantum (SFQ) electronics. A major roadblock towards implementing scalable
quantum computers and practical SFQ circuits is the lack of suitable and
compatible cryogenic memory that can operate at 4 Kelvin (or lower)
temperature. Cryogenic memory is also critically important in space-based
applications. A multitude of device technologies have already been explored to
find suitable candidates for cryogenic data storage. Here, we review the
existing and emerging variants of cryogenic memory technologies. To ensure an
organized discussion, we categorize the family of cryogenic memory platforms
into three types: superconducting, non-superconducting, and hybrid. We
scrutinize the challenges associated with these technologies and discuss their
future prospects.Comment: 21 pages, 6 figures, 1 tabl
Reorientation of the stripe Phase of 2D Electrons by a Minute Density Modulation
Interacting two-dimensional electrons confined in a GaAs quantum well exhibit
isotropic transport when the Fermi level resides in the first excited ()
Landau level. Adding an in-plane magnetic field () typically leads to
an anisotropic, stripe-like (nematic) phase of electrons with the stripes
oriented perpendicular to the direction. Our experimental data reveal
how a periodic density modulation, induced by a surface strain grating from
strips of negative electron-beam resist, competes against the -induced
orientational order of the stripe phase. Even a minute () density
modulation is sufficient to reorient the stripes along the direction of the
surface grating.Comment: Accepted for publication in Phys. Rev. Let
Reducing switching losses of resonant inverter
This thesis report is submitted in partial fulfillment of the requirements for the degree of Bachelor of Science in Electrical and Electronic Engineering, 2015.Inverter is used in different purposes of lives. Inverters are required in a variety of applications including electronic ballasts for gas discharge lamps, induction heating and electrosurgical generators. These applications usually require a sinusoid of tens or hundreds of kHz having moderate or low harmonic distortion. Induction heater is another field where inverter is needed. It is one of the popular techniques of producing high temperature. Since the inverter has been invented long ago now different types of topologies came to light. Resonant inverter is one of them. Voltage and current source inverter was invented before resonant inverter, but resonant inverter has brought something new in engineering society. Now here is a point why resonant inverter is more important than voltage and current source inverter especially for those applications where output power control is needed. A very common term in electrical field is switching loss. In normal inverter circuits when the switches swap their positions they consume some powers, as they conduct their activities when both current and voltage are nonzero. As a result of imperfect switching causes power loss which is strongly unexpected. Moreover with the increase of switching frequencies power loss increases. As expected smaller size filter components needed higher frequencies. So the invented solution for avoiding the power loss is using a new type of inverter which is known as resonant inverter. The most significant part of resonant inverter is, here switching takes place when voltage and current are zero which is known as ‗soft switching‘. Since switching takes place in zero voltage and current stage there is no possibility of power loss in resonant inverter
Observation of fractional quantum Hall effect in an InAs quantum well
The two-dimensional electron system in an InAs quantum well has emerged as a
prime candidate for hosting exotic quasi-particles with non-Abelian statistics
such as Majorana fermions and parafermions. To attain its full promise,
however, the electron system has to be clean enough to exhibit
electron-electron interaction phenomena. Here we report the observation of
fractional quantum Hall effect in a very low disorder InAs quantum well with a
well-width of 24 nm, containing a two-dimensional electron system with a
density cm and low-temperature mobility cm/Vs. At a temperature of mK and T, we
observe a deep minimum in the longitudinal resistance, accompanied by a nearly
quantized Hall plateau at Landau level filling factor