Abstract: Technologies are generally described for forming graphene and structures including graphene. In an example, a system effective to form graphene may include a chamber adapted to receive graphite oxide. The system may also include a source of an inert gas and a source of hydrogen, which may both be configured in communication with the chamber. A processor may be configured in communication with the chamber, the inert gas source and/or the hydrogen source. The processor may be further configured to control the flow of the inert gas from the first source through the chamber under first sufficient reaction conditions to remove at least some oxygen from the atmosphere of the chamber. The processor may also be configured to control the flow of the hydrogen from the second source to the graphite oxide in the chamber under second sufficient reaction conditions to form graphene from the graphite oxide.

Abstract: Methods for fabricating a piezoelectric device are provided. The methods can include providing a substrate and forming a nanocrystalline diamond layer on a first surface of the substrate. The methods can also include depositing a piezoelectric layer on a first surface of the nanocrystalline diamond layer.

Abstract: Methods of forming a diatom-based nanocomposite are provided. The methods include mixing at least one diatomic material, one or more metal precursors, and functionalized graphite oxide to form a mixture. The methods also include exfoliating the mixture in presence of hydrogen to reduce functionalized graphite oxide to graphene and reducing the one or more metal precursors to metal nanoparticles. The methods further include depositing the metal nanoparticles on the diatomic material to form the diatom-based nanocomposite.

Abstract: A non-invasive method for estimation of strain profile and dynamic evolution of the strain at a location interposed inside a block of soft material, includes forming a tracer grid consisting of microscopic lines or regularly spaced microscopic dots on a single plane buried inside the soft block; preparation of a deformable object embedded with the tracer grid in three primary steps: i. preparing a block of crosslinked material by crosslinking a first predetermined quantity of a pre-polymer solution containing a monomer, a crosslinking agent, and an initiator and promoter all mixed in a solvent at a known stoichiometric weight ratio; ii. transferring a grid comprising of lines or dots onto the face by direct writing or transferring from an easy release surface; and iii. crosslinking a second predetermined quantity of the same pre-polymer solution on the gel surface, such that this second crosslinked material gets welded to the first one.

Abstract: An apparatus for measuring rheological properties of a multi-phase fluid is provided. The apparatus includes a static chamber configured to contain a multi-phase fluid having at least a first phase and a second phase. The apparatus also includes a rotor member submersed in the multi-phase fluid in the static chamber. The rotor member is rotatable about a horizontal rotational axis within the static chamber and the static chamber and the rotor member are oriented in a substantially horizontal direction.

Abstract: A metal nanoparticles-doped porous carbon bead having an average size of about 0.4 millimeter (mm) to about 0.6 mm is provided. The metal nanoparticles-doped porous carbon bead is doped with silver, copper, or combinations thereof.

Abstract: Methods of forming a metal-alloy graphene nanocomposites are provided. The methods include providing a graphene substrate and forming a conducting polymer layer on a first major surface of the graphene substrate. The methods also include pyrolyzing the conducting polymer layer to form a nitrogen-doped graphene substrate and dispersing a plurality of metal-alloy nanoparticles on a first surface of the nitrogen-doped graphene substrate to form the nanocomposite.

Abstract: Embodiments herein provide a Multiple-Input Multiple-Output (MIMO) method for a communication system in general, and more particularly to an Orthogonal Frequency Division Multiplexing (OFDM) based communication system to serve more than one receivers on the same resources. The method includes selecting, by a transmitter, a plurality of precoder matrices for a plurality of receivers from a predefined codebook of precoders, where the plurality of precoder matrices is dynamically cycled within an allocated resource. Further, the method includes transmitting, by the transmitter, a symbol vector precoded with the plurality of precoder matrices over MIMO channel associated with the plurality of receivers.

Abstract: Technologies are generally described for a four-terminal, gate-controlled, thin-film thyristor device. The thyristor device may essentially be an n-type thin-film transistor (TFT) with an additional emitter terminal. The thyristor device may exhibit an S-shaped negative differential resistance (NDR) characteristic resulting from conductance modulation. The conductance modulation may be caused by formation of a secondary channel for current flow due to an inherent structure of the device. The secondary channel may be formed in a semiconductor area within the device, the semiconductor area including a hole transporting organic semiconductor layer (HTL) and an electron transporting organic semiconductor layer (ETL). A gate terminal of the thyristor device may further allow onset of NDR characteristics to be controlled and may allow the device to be switched off.

Abstract: Bi-metal nanoadsorbents and methods for their preparation and use are provided. Methods of using bi-metal nanoadsorbents to remove contaminants from samples, such as water, are also provided.

Abstract: Technology is generally described for improving resistance to cache timing attacks made on block cipher encryption implementations. In some examples, the technology can include identifying one or more tunable parameters of the block cipher encryption algorithm; creating multiple encryption algorithm implementations by varying one or more of the parameter values; causing a computing system to encrypt data using the implementations; measuring average execution times at the computing system for the implementations subjecting the implementations to a cache timing attack; measuring average execution times at the computing system for the implementations subjected to a cache timing attack; computing a time difference between the average execution times for the implementations when not subjected and when subjected to a cache timing attack; selecting an implementation having a lower time difference; and using the selected implementation for a subsequent encryption operation.

Abstract: Methods and systems for managing relays in LTE based communication networks. Embodiments herein use of a packet handler node and an additional radio interface in the UE, enabling the creation of an overlay network on top of an existing LTE network. The overlay network helps in the transfer of data between the UE and the AS even when the UE is not directly connected to the LTE network by encapsulating the data from the out-of-coverage UE within the IP packet of at least one nearby relay UE connected to the LTE network and is then forwarded to the LTE core network. The out-of-coverage UE uses the additional radio interface to send packets to the relay UE.

Abstract: Embodiments herein provide a modular multilevel converter configured to increase one of number of an output voltage level and an output current level. The modular multilevel converter includes a plurality of legs where each leg includes a plurality of arms. Each arm of the modular multilevel voltage source converter includes a main wave shaping (WS) circuit, an auxiliary WS circuit and an arm inductor. The main WS circuit includes one or more half bridge sub-module(s) that includes a capacitor. The auxiliary WS circuit includes one or more full bridge sub-module(s) that includes a capacitor. Each arm of the modular multilevel current source converter comprises a plurality of half-bridge modules connected in parallel, and a plurality of arm capacitor connected across the plurality of half-bridge modules and one or more auxiliary full bridge module(s).

Abstract: A system for early detection of onset of oscillatory instabilities in practical devices is described. The system consists of a measuring device, an instability detection unit and a control unit. The measuring device is configured to generate signals corresponding to the dynamics happening inside the practical device. The instability detection unit is configured to diagnose the stability of the practical device from the signals that are generated by the measuring device. Further, the control unit is configured to control various operating parameters in the practical device based on the information obtained from the instability detection unit.

Abstract: Embodiments herein provide a method of estimating channel states of a plurality of user equipments (UEs) in a single instance. The method includes receiving pilot samples from the plurality of UEs. The method includes selecting a predetermined number of tones, wherein the channel associated with each UE across the selected pre-determined number of tones is same. The method includes collecting the received pilot samples from each pilot symbol and stacking the received pilot samples as a vector. Further, the method includes constructing a matrix. The matrix includes known pilot values used by each UE. Furthermore, the method includes estimating channel states of the plurality of UEs by applying a filter on the vector formed from the received pilot samples. The number of channel states to be estimated is reduced by selecting the pre-determined number of tones.

Abstract: A highly available network architecture for a LTE based communication network. Embodiments herein disclose an architecture for a highly available and resilient Long Term Evolution (LTE) based wireless communication network, wherein the network comprises of at least one Base Station (BS) further comprising of a merged LTE eNodeB (eNB) and a LTE Evolved Packet Core (EPC) entities and except for a single active BS, the other BSs can act as a backup for the currently active BS. Embodiments herein disclose a network architecture for a highly available and resilient architecture for Long Term Evolution (LTE) based wireless communication network, wherein a LTE radio interface is used for connectivity between components of the LTE communication network.

Abstract: Standalone LTE based communication networks. Embodiments herein disclose methods and systems for providing LTE based communication to at least one User Equipment (UE) over a small region using a rapidly deployable standalone network wherein at least one LTE UE would be able to connect to an Application Server (AS).

Abstract: A polymer based photo-detector has photoresponsivity in Ultraviolet, Visible, Near and Mid Infrared regions. The photo-detector comprises a single layer of polyvinyl alcohol (PVA) as a photoactive layer; with no additional buffer layer for accepting Ultraviolet, Visible and Infrared radiation as well as no buffer layer to block charge carrier injection. The PVA layer's photoresponsivity is extended from Ultraviolet to Near Infrared by changing its nano-morphology on a low thermal device structure. The primarily photo-generated charge carriers diffuse through the amorphous part of the polymer layer and split into charge carriers on the electrodes or by the charge traps in the layer. The charge carrier generation is in the picosecond range; thus the exciton and Polaron drift diffusion cause electrical conduction of the polymer layer under Ultraviolet illumination.

Abstract: Systems and methods for imaging characteristics of a sample and for identifying regions of damage in the sample are generally described. Some example systems and methods for non-destructive evaluation of regions of material may operate in a direct current (DC) mode in which the system directly images regions of material where weak structural damage has occurred by imaging a self magnetic field generated by a DC electric current coupled through the material. Some example systems may operate in an alternating current (AC) mode to image regions of material where damage has occurred by generating a time varying magnetic field due to AC excitation coils inducing eddy currents in the sample, and imaging a magnetic field generated by the eddy currents around the regions of damage. The systems may use magneto-optical imaging techniques (MOI) to measure and map the magnetic field and channels of current flow in the material, for example.