The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
This paper presents the results of a series of tests to determine the influence of high-frequency injected ripple currents on the Dynamic Charge Acceptance (DCA) performance of lead-acid batteries. A wide-bandwidth battery model is described, this being a hybrid of the standard Randles model and a high-frequency model previously described in literature. A bespoke test procedure is described, based...
This paper investigates methods of magnet mass reduction in linear flux switching permanent magnet (LFSPM) machines by introducing tapered consequent poles. Based on the finite element analysis (FEA) three different models are designed, investigated and compared. The obtained results indicate that by adopting the proposed tapered ferromagnetic poles a considerable saving of material cost and weight...
In this paper a novel E-core Linear Variable Reluctance Vernier Hybrid Permanent Magnet (LVR-VHPM) machine with inherent magnetic gearing is proposed for use in the long stroke application of a wave energy converter. The proposed topology is a combination of a doubly salient flux reversal machine, a consequent pole machine and a surface mounted Halbach array Permanent Magnet (PM) machine. The stator...
RADEval is a tool developed to assess the expected clinical impact of contouring accuracy when comparing manual contouring and semi-automated segmentation. The RADEval tool, designed to process large scale datasets, imported a total of 2,760 segmentation datasets, along with a Simultaneous Truth and Performance Level Estimation (STAPLE) to act as ground truth tumor segmentations. Virtual dose-maps...
The range of candidate bands considered for 5G wireless systems extends from 6-100 GHz. In this paper we examine the impact of key parameters of millimeter-wave (mmWave) and microwave channel models on various system performance metrics, e.g., spectral efficiency, eigenvalue structure and convergence to massive multiple-input multiple-output (MIMO) properties. We consider 6 spatial channel model (SCM)...
Heralded single-photon sources are a standard experimental tool for studying quantum optics and quantum information in few-photon systems. These sources use spontaneous parametric wave mixing to probabilistically emit pairs of photons. One photon of the pair, the heralding photon, is detected to indicate the presence of the other. In theory, the maximal probability of emitting a single pair of photons...
Failures in Umbilicals caused by insulation breakdown from partial discharge (PD) in MV cables can lead to excessive down time and costs. Ideally these discharges would be detected & located before complete breakdown occurred. This paper discusses acoustic emission sensing methods used to detect PD events along with time difference of arrival (TDOA) and time delay estimation (TDE) algorithms to...
The uniqueness of the ITER fusion project drives purpose and scope here to fulfil (functional) Procurement Arrangement (PA) requirements for the Central Solenoid (CS) and Correction Coil (CC) magnets' electrical insulation [1–3]; as used and undertaken for covering high voltage testing operations of the magnet coil winding pack (WP) vacuum pressure insulation (VPI) beam qualification, followed in...
A miniature in-situ CH4 concentration measurement instrument based upon tunable laser spectroscopy (TLS) was developed and applied in numerous field campaigns. The instrument, a 3.4 μm laser spectrometer developed at NASA Jet Propulsion Lab (JPL), is lightweight (250g), low power (< 8 W), and high sensitivity (10 ppb s−1). The payload was further developed and integrated onto a small UAV at UC...
Wave energy conversion can be simplified by using direct drive linear generators which may improve reliability. Numerous topologies of direct drive linear generators have been proposed in the last few decades such as the linear vernier hybrid permanent magnet (LVHPM) machine. However, the cost of this kind of machine is driven by the quantity of permanent magnet (PM) material. This paper proposes...
Results of recent measurement campaigns demonstrate a significant increase in the degrees of freedom introduced by the elevation domain, and consequently, a large capacity gap as predicted by 3D and 2D MIMO channel models. To gain further insight into the effects of the elevation domain on MIMO system performance, we derive new spatial correlation (SC) expressions for 3D and 2D channel models, given...
This paper proposes a new topology of a Linear Veriner Hybrid Permanent Magnet (LVHPM) machine with E-core stators and a segmented chamfered translator, which is shown to give mass reduction and better magnetic flux path compared to existing designs. Linear Permanent Magnet (PM) generators have the capability to reduce the number of moving parts, providing a simpler mechanical drive train when used...
Energy and Process control systems were once conveniently separated. Tighter integration is now required because of more widespread use of higher efficiency motors and variable frequency drives as well as faster dynamic load management schemes for plants with a minimal spinning reserve capability. Digital age IIoT interactions between the ANSI/ISA95 and IEC61850 Bus Architectures present challenges...
We analyze topological entropy in wireless networks that are subject to local scattering and macroscopic shadowing effects. To this end, we model a network as a random geometric graph with probabilistic pair connections (due to channel randomness) and define uncertainty as the Shannon entropy of the underlying graph ensemble. We present new bounds on topological entropy that are functionals of the...
Nowadays, planning studies for distribution power systems require the inclusion of non-conventional loads. These loads refer to devices that converts energy integrating multiple functionalities not included in traditional simulation tools. These technologies are continuously changing and adding new functionalities that need to be tested before being implemented by utilities. However, most available...
Closed-form approximations to the expected perterminal signal-to-interference-plus-noise-ratio (SINR) and ergodic sum spectral efficiency of a large multiuser multiple-input multiple-output system are presented. Our analysis assumes correlated Ricean fading with maximum ratio combining on the uplink, where the base station (BS) is equipped with a uniform linear array (ULA) with physical size restrictions...
Growth in voice-based applications and personalized systems has led to increasing demand for speech- analytics technologies that estimate the state of a speaker from speech. Such systems support a wide range of applications, from more traditional call-center monitoring, to health monitoring, to human-robot interactions, and more. To work seamlessly in real-world contexts, such systems must meet certain...
Large Engineered Adjustable Speed Drive Systems are typically rated above 7kV, 5,000 or 10,000hp and are considered “engineered products and systems” (i.e. “one-of-a-kind” or “one-off” designs) as opposed to “off the shelf” equipment. As such, they require more attention to application, design, system validation and commissioning than typical “off-the-shelf” equipment and systems. Hazards associated...
Additive manufactured prototypes based on a novel inverted-F antenna design are presented and measured results discussed. Radiation efficiency is computed with the aid of a Wheeler cap box; the resulting ratio of the antenna's quality factor to the lower limit described by Chu is shown to be 1.9 for a spherical variant. Measured and simulated S-parameter results show good agreement, with some evident...
We present a method to completely characterize the temporal wave function of heralded single photons using spectral shearing interferometry. Frequency shear is applied by electro-optic modulation and spectrally-resolved detection is performed by frequency-to-time spectrometry.
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.