Accurate Energy Measurements Research Articles

Verification Scheme and System Design of Charging Pile Electric Energy Measurement

Design a charging pile electric energy verification device to improve the electric energy measurement accuracy of the charging pile. The device is mainly used for detecting whether the charging pile can be correctly configured, including a tariff period, a billing unit power, a billing rate, and the like, and detecting the communication reliability of the charging station. The test charges the pile output data by the broadband current comparator. Through RS485 communication mode, the instrumentation communication with the charging pile is always used to improve the accuracy of detection and measurement. The design and development of the DC charging pile verification device promoted the construction of the charging infrastructure and solved the charging problem of the electric vehicle.

Using a Lithium Glass Scintillator to Record Neutron Radiation

Studies have been performed to improve the accuracy of energy measurements of neutron fields and to improve the spectrometric analysis of neutron radiation fields using scintillation detectors. The use of a scintillation detector based on 6Li2O lithium glasses of various diameters and thicknesses for recording neutron radiation energy, 0.4–15·106 eV, is considered. The main characteristics of this scintillation detector and the results of measurements obtained with it are compared with the characteristics and results of measurements of the scintillator using LiI (Eu). Spherical moderators with diameters of 70–300 mm were used for scintillation detector operation.

Count‐rate, linearity, and performance of new backgammon detector technology

The meander wire backgammon technology has high levels of flux and spatial linearity across a wide range of energies. One of the attractive features of these technologies is the stability of response and robustness under long X‐ray exposure, compactness, and portability. A key problem historically has been the limited range of count‐rate for processing to the optimum resolution. We report dramatic advances in this and other areas appropriate for high‐accuracy experiments including tests of quantum electrodynamics, fundamental relativistic atomic physics, X‐ray calibration, and crystallography. We illustrate this technology applied to the Kα1,2 spectra of titanium, chromium, and copper. The quality of the spectra permits deeper insight into atomic and solid state science and permits accurate measurement of energy and relativistic atomic physics processes, below 1‐μm accuracy or down to 1 ppm in energy.

Effect of specimen geometry on kinetics of thermal decomposition of minerals in porous ceramic tiles

AbstractPorous ceramic tiles are used as covering for indoor vertical surfaces in buildings. Clay and limestone are the starting raw materials. The firing step consolidates the product's properties in the manufacturing process. In this step several reactions occur, among them are the dehydroxylation of the clay minerals and decomposition of the carbonates. This study determined the kinetics parameters associated with the decomposition of these 2 minerals. Two different methods of samples preparation were investigated. In the first method, 60 mg of a spray‐dried powder was submitted to analysis in traditional thermogravimetric equipment. In the second method, compacted specimens with dimensions of 80 × 20 × 2.5 mm³ and a mass of 7 g, compacted at 25 MPa, were submitted to analysis using customized thermogravimetric apparatus. The curves were obtained for 6 different heating rates between 2.5 and 20 K min−1. The activation energy, the pre‐exponential factor of the specific velocity equation, and the reaction mechanism were determined. Depending on the methods and compaction degree the activation energy varies from 177.0 to 224.7 kJ mol−1 and from 188.5 to 230.2 kJ mol−1 for kaolinite and calcium carbonate, respectively. For accurate measurement of the activation energy, the heat transfer needs to be considered for each particular experimental configuration.

Systematic uncertainty of first-principle calculations of the radiation energy emitted by extensive air showers

The energy of extensive air showers can be determined from the energy radiated in the form of radio signals. The so-called radiation energy can be predicted with modern simulation codes using first-principle calculations without the need of free parameters. Here, we verify the consistency of radiation energy calculations by comparing a large set of Monte Carlo simulations made with the two codes CoREAS and ZHAireS. For the frequency band of 30 — 80 MHz, typically used by many current radio detectors, we observe a difference in the radiation energy prediction of 5.2%. This corresponds to a radio emission modelling uncertainty of 2.6% for thedetermination of the absolute cosmic-ray energy scale. Hence, radio detection offers the opportunity for a precise, accurate and independent measurement of the absolute energy of cosmic rays.

Assessment, Intervention, and Monitoring: Stepwise Nutritional Management in Pediatric Intensive Care Units: A Short Review

Context: Previous studies have indicated that 24 - 53 of children admitted to pediatric intensive care units (PICUs) suffer from acute or chronic malnutrition at admission. Furthermore, a large number of them undergo deterioration in nutritional status during hospitalization. Critically ill children are at an increased risk of malnutrition because of altered metabolism, and baseline nutritional assessment helps identify those patients at risk of developing malnutrition or further nutritional deterioration. This leads to an early nutritional intervention, which is the ultimate goal of nutrition support therapy. Principal Findings: This review was conducted to describe three main steps of nutritional management (baseline nutritional assessment, nutritional intervention, and monitoring) in PICU admitted patients and discuss the importance and considerations of each step. According to the fact that early and proper nutritional support is seriously important in intensive care medicine, considering a stepwise approach toward nutrition management in pediatric intensive care units might be so useful. The assessment of nutritional status, identifying patients at risk of further nutritional deterioration, accurate measurement of energy and nutrient need for each patient, initiating nutrition support based on the nutrition support team (NST)-approved protocols, and regular assessment of anthropometry and nutritional parameters during the admission period are the stepwise phases of nutritional management in PICU patients. Conclusions: Following these steps might reduce the number of PICU patients who deteriorate mainly due to the poor or late nutritional support. Copyright © 2018, Journal of Comprehensive Pediatrics.

Improved Parameter Identification Method for Envelope Current Signals Based on Windowed Interpolation FFT and DE Algorithm

Envelope current signals are increasingly emerging in power systems, and their parameter identification is particularly necessary for accurate measurement of electrical energy. In order to analyze the envelope current signal, the harmonic parameters, as well as the envelope parameters, need to be calculated. The interpolation fast Fourier transform (FFT) is a widely used approach which can estimate the signal frequency with high precision, but it cannot calculate the envelope parameters of the signal. Therefore, this paper proposes an improved method based on windowed interpolation FFT (WIFFT) and differential evolution (DE). The amplitude and phase parameters obtained through WIFFT and the envelope parameters estimated by the envelope analysis are optimized using the DE algorithm, which makes full use of the performance advantage of DE. The simulation results show that the proposed method can improve the accuracy of the harmonic parameters and the envelope parameter significantly. In addition, it has good anti-noise ability and high precision.

Fluorescent nuclear track detectors for alpha radiation microdosimetry

BackgroundWhile alpha microdosimetry dates back a couple of decades, the effects of localized energy deposition of alpha particles are often still unclear since few comparative studies have been performed. Most modern alpha microdosimetry studies rely for large parts on simulations, which negatively impacts both the simplicity of the calculations and the reliability of the results. A novel microdosimetry method based on the Fluorescent Nuclear Track Detector, a versatile tool that can measure individual alpha particles at sub-micron resolution, yielding accurate energy, fluence and dose rate measurements, was introduced to address these issues.MethodsBoth the detectors and U87 glioblastoma cell cultures were irradiated using an external Am241 alpha source. The alpha particle tracks measured with a Fluorescent Nuclear Track Detector were used together with high resolution 3D cell geometries images to calculate the nucleus dose distribution in the U87 glioblastoma cells. The experimentally obtained microdosimetry parameters were thereafter applied to simulations of 3D U87 cells cultures (spheroids) with various spatial distributions of isotopes to evaluate the effect of the nucleus dose distribution on the expected cell survival.ResultsThe new experimental method showed good agreement with the analytically derived nucleus dose distributions. Small differences (< 5%) in the relative effectiveness were found for isotopes in the cytoplasm and on the cell membrane versus external irradiation, while isotopes located in the nucleus or on the nuclear membrane showed a substantial increase in relative effectiveness (33 – 51%).ConclusionsThe ease-of-use, good accuracy and use of experimentally derived characteristics of the radiation field make this method superior to conventional simulation-based microdosimetry studies. Considering the uncertainties found in alpha radionuclide carriers in-vivo and in-vitro, together with the large contributions from the relative biological effectiveness and the oxygen enhancement ratio, it is expected that only carriers penetrating or surrounding the cell nucleus will substantially benefit from microdosimetry.

Comparison of sensible heat flux measured by large aperture scintillometer and eddy covariance in a seasonally-inundated wetland

The eddy covariance (EC) technique has been widely used to measure ecosystem surface energy fluxes. However, with a relatively small representative area (footprint), errors are often introduced when upscaling EC data based on variables derived from large-footprint satellite products. Furthermore, EC measurements often fail to close the energy balance in ecosystems such as wetlands. As an alternative to EC, large aperture scintillometers (LAS) have been used to measure sensible heat fluxes (H) over representative areas comparable to the resolution of large-scale satellite images. However, because LAS measurements are based on semi-empirical simulations, their accuracy needs further evaluation across ecosystems. Changes in hydrology on the land surface significantly alter measurement conditions as well as the processes of energy transfer, and thus, may affect the accuracy of energy measurements from LAS. To address this issue, we compared the LAS-measured H (HLAS) to EC-derived H (HEC) in a seasonally inundated wetland within Everglades National Park. Overall, the HLAS was 7.1 ± 0.3 (SE) % greater than HEC, and the ratio of HLAS to HEC remained similar between the wet season, when the ecosystem was inundated, and the dry season. However, inundation, as a thermal buffer in the system, reduced the magnitude of H in the wet season and resulted in a smaller difference of seasonal H budget estimates between LAS and EC measurements. Because of the homogenous land surface at our site, the discrepancies between HLAS and HEC could not be explained by footprint mismatch. Compared to the energy balance closure calculated with HEC, the closure calculated with HLAS was improved by 6% during the dry season but remained similar during the wet season. Overall, we conclude that LAS can be a reliable approach to measure H in wetland ecosystems and its measurements were stable with seasonal hydrological changes.

Probing the pathways of free charge generation in organic bulk heterojunction solar cells

The fact that organic solar cells perform efficiently despite the low dielectric constant of most photoactive blends initiated a long-standing debate regarding the dominant pathways of free charge formation. Here, we address this issue through the accurate measurement of the activation energy for free charge photogeneration over a wide range of photon energy, using the method of time-delayed collection field. For our prototypical low bandgap polymer:fullerene blends, we find that neither the temperature nor the field dependence of free charge generation depend on the excitation energy, ruling out an appreciable contribution to free charge generation though hot carrier pathways. On the other hand, activation energies are on the order of the room temperature thermal energy for all studied blends. We conclude that charge generation in such devices proceeds through thermalized charge transfer states, and that thermal energy is sufficient to separate most of these states into free charges.

Performance of the CMS precision electromagnetic calorimeter at LHC Run II and prospects for High-Luminosity LHC

Many physics analyses using the Compact Muon Solenoid (CMS) detector at the LHC require accurate, high-resolution electron and photon energy measurements. Following the excellent performance achieved during LHC Run I at center-of-mass energies of 7 and 8 TeV, the CMS electromagnetic calorimeter (ECAL) is operating at the LHC with proton-proton collisions at 13 TeV center-of-mass energy. The instantaneous luminosity delivered by the LHC during Run II has achieved unprecedented levels. The average number of concurrent proton-proton collisions per bunch-crossing (pileup) has reached up to 40 interactions in 2016 and may increase further in 2017. These high pileup levels necessitate a retuning of the ECAL readout and trigger thresholds and reconstruction algorithms. In addition, the energy response of the detector must be precisely calibrated and monitored. We present new reconstruction algorithms and calibration strategies that were implemented to maintain the excellent performance of the CMS ECAL throughout Run II. We will show performance results from the 2015-2016 data taking periods and provide an outlook on the expected Run II performance in the years to come. Beyond the LHC, challenging running conditions for CMS are expected after the High-Luminosity upgrade of the LHC (HL-LHC) . We review the design and R&D studies for the CMS ECAL and present first test beam studies. Particular challenges at HL-LHC are the harsh radiation environment, the increasing data rates, and the extreme level of pile-up events, with up to 200 simultaneous proton-proton collisions. We present test beam results of hadron irradiated PbWO crystals up to fluences expected at the HL-LHC . We also report on the R&D for the new readout and trigger electronics, which must be upgraded due to the increased trigger and latency requirements at the HL-LHC.

Implementation of Smart Metering based on Internet of Things

From the aspect of saving energy, there is a continuous modification in communication technology and information in order to satisfy all customers demand. Today customers are demanding for accurate energy measurement, timely data and for good customer services. The best solution is smart grid system with various communication technologies which can be cost effective and electrical section to have a bidirectional communication in which information about electrical energy consumption is shared between consumers as well as by utility for remote checking. This paper describes the monitoring of energy consumption with Arduino Uno board and Ethernet using IoT (Internet of Things) concept. This proposed design eliminates human inclusion in the conservation of electricity. The consumer can receive the information about consumption of energy by using IP address on their devices. The web client code is uploaded for checking the client information such as location, content, connection, and disconnection to the web server. This proposed system gives reliable and accurate information regarding electrical energy management system (EMS) through Internet of things (IoT).

Research on the Influence of Load Characteristics of Distributed Power Grid on Electric Energy Metering

As a large number of Distributed Generation Connecting Electric Grid put into operation, there are many impacts on power metering of power grid due to the problems of large fluctuation of load and frequent reverse of power, injecting DC component and harmonic component into power grid, generating voltage deviation, voltage fluctuation and flicker, and voltage unbalance. Measurement accuracy of traditional metering devices is difficult to guarantee. Therefore, the adaptability of traditional metering devices in the distributed power grid environment and the improvement of new technical methods to the Distributed Generation Connecting Electric Grid need to be studied. In this paper, through the analysis of the field operation data, it is proposed that the load fluctuation and frequent reverse of power can be solved by using the bidirectional and wide-range metering gateway meter; by analyzing the influence of the secondary transformer on the DC component, it is proposed that the influence of the DC component on the power metering can be almost ignored under the 0.5% DC component injection of the Distributed Generation Connecting Electric Grid. By analyzing zero flux technology, phase matching technology and high frequency sampling technology, a method to solve the problem of synchronous sampling of voltage and current under the influence of harmonics is proposed. By analyzing the point product and harmonic algorithm, the sampling rate requirement of accurate measurement of electric energy is proposed. A series of reasonable technical means and requirements are put forward in this paper, which greatly improves the power metering problem under the Distributed Generation Connecting Electric Grid.

Design of an energy analyzer for low energy 1+ charged ion beams at RISP Project

Accurate measurement of the energy spread with a compact device has been accomplished by developing a new prototype of a retarding field energy analyzer (RFEA). The device is capable of handling all kinds of low energy mono-charged ion beams at RISP Project. Numerical simulations have been performed in order to study and evaluate dependency of RFEA energy resolution to beam emittance, beam energy, beam energy spread, space charge effects, and most significantly the optics system. Simulation results have shown that the use of developed optics system with particular voltage applied on the focusing cylinder and suitable positioning of the retarding grid may lead to high efficiency energy resolutions not exceeding 0.31 eV for beam energy going up to 20 keV . Small errors on the measured energy spread are obtained despite the presence of degradations stemming from various energy resolution dependencies. Typical mono-charged ion beams delivered from ion trap devices, ISOL beam-line and stable ion sources have been studied. The error on the optimum measured energy spread for beams delivered from ion trap devices is 5 ∼ 10% owing to beam emittances. For a larger beam size, delivered from an ISOL beam-line, a larger error occurs on the measured energy spread at around 23.5%. The energy spread of ion beams delivered from stable ion sources with good optical quality relative to the ISOL sources can be measured with an error around 21.7%. This prototype enables accurate measurement of the average beam energy with an error around 1.5 eV per 20 keV beam energy.

Laser backscattering for beam energy calibration in collider experiments

Laser backscattering was implemented as a tool for accurate beam energy measurement at three of the five existing electron-positron colliders. The present report summarizes the experience obtained during these experiments.

Elastic-plastic analysis of the adhesively bonded end-notched flexure specimen

The end-notched flexure (ENF) specimen has often been employed to characterise the mode II fracture of adhesive joints. This paper reports a beam model for ENF specimens with metal adherends and typical bondline thickness values. The initial formulation adopting adhesive linear elasticity predicted accurately the shear stress distribution, the compliance and the strain-energy release rate. The adhesive elastic-perfectly plastic behaviour subsequently introduced generated a plastic zone whose size could be predicted by a closed-form expression. The model provides a basis for selecting specimen geometries that enable accurate fracture energy measurements from a corrected beam theory with effective crack length scheme.

A new method for the measurement and analysis of biomechanical energy delivered by kicking

An accurate measurement of force and biomechanical energy that people can impart through kicking is useful for kick-related sports training. Existing methods are indirect measurements or focus on force and not on the total energy of the kick. A kick test rig was designed, constructed and instrumented to measure the force and displacement of a vertical target subjected to kicking. The kick energy was calculated from the recorded force and displacement histories. The methodology for measurement of kick force and energy was validated by an open stance front kick test by 52 volunteers. The results showed that 67% of the participants could achieve an average energy above 100 J. An increasing trend of kick energy with increasing body weight of participant was observed. The participant’s gender had a strong influence on the kick energy, while training in martial arts does not appear to be a significant parameter. A probability analysis showed that one in one hundred adults will be able to kick with energies exceeding 215 J.

RBE study using solid state microdosimetry in heavy ion therapy

The response of two types of 10 μm thick silicon-on-insulator (SOI) detectors in a 12C ion therapy beam with extremely high spatial resolution are presented in this work. The two detectors used are the “bridge” microdosimeter with isolated 3D sensitive volumes (SVs) and the ultra-thin 3D (U3DTHIN) detector with n+ and p+ 3D columnar structures. Both detectors were investigated at various depths in a water phantom along the central axis of the spread-out Brag peak (SOBP) of a 290 MeV/u 12C ion beam at the Heavy Ion Medical Accelerator in Chiba, Japan. Based on the Microdosimetric Kinetic (MK) model and the microdosimetric quantities measured with the two detectors, the relative biological effectiveness (RBE) values were derived and compared to results obtained with the tissue-equivalent proportional counter (TEPC). Derived RBE10 values obtained with the U3DTHIN detector were considerably higher than those obtained with the bridge microdosimeter and the TEPC along the SOBP. Due to the high spatial resolution of the microdosimeters, more detailed measurements were obtained at the end of the SOBP compared to the TEPC. The maximum derived RBE10 found using the U3DTHIN detector and bridge microdosimeter were approximately 2.66 and 2.58, respectively which are higher than the RBE10 value of 2.35 obtained with the TEPC due to the lack of high spatial resolution in the TEPC. The discrepancy in the results obtained using the two detectors is due to the difference in geometry of the SVs in the two detectors. This work presents an application of different types of SOI micodosimeters in a 12C ion therapy beam and has demonstrated that the microdosimeter with micron sized 3D SVs is more desirable for accurate lineal energy measurement and RBE determination. Silicon microdosimetry has demonstrated a simple, fast and accurate method for routine Quality Assurance in charged particle therapy.

Marcher: A Heterogeneous System Supporting Energy-Aware High Performance Computing and Big Data Analytics

Abstract Excessive energy consumption is a major constraint in designing and deploying the next generation of supercomputers. Minimizing energy consumption of high performance computing and big data applications requires novel energy-conscious technologies (both hardware and software) at multiple layers from architecture, system support, and applications. In the past decade, we have witnessed the significant progress toward developing more energy-efficient hardware and facility infrastructure. However, the energy efficiency of software has not been improved much. One obstacle that hinders the exploration of green software technologies is the lack of tools and systems that can provide accurate, fine-grained, and real-time power and energy measurement for technology evaluation and verification. Marcher, a heterogeneous high performance computing infrastructure, is built to fill the gap by providing support to research in energy-aware high performance computing and big data analytics. The Marcher system is equipped with Intel Xeon CPUs, Intel Many Integrated Cores (Xeon Phi), Nvidia GPUs, power-aware memory systems and hybrid storage with Hard Disk Drives (HDDs) and Solid State Disks (SSDs). It provides easy-to-use tools and interfaces for researchers to obtain decomposed and fine-grained power consumption data of these primary computing components. This paper presents the design of the Marcher system and demonstrates the usage of Marcher power measurement tools to obtain detailed power consumption data in various research projects.

Precision determination of electron scattering angle by differential nuclear recoil energy method

The accurate determination of the scattered electron angle is crucial to electron scattering experiments, both with open-geometry large-acceptance spectrometers and ones with dipole-type magnetic spectrometers for electron detection. In particular, for small central-angle experiments using dipole-type magnetic spectrometers, in which surveys are used to measure the spectrometer angle with respect to the primary electron beam, the importance of the scattering angle determination is emphasized. However, given the complexities of large experiments and spectrometers, the accuracy of such surveys is limited and insufficient to meet demands of some experiments. In this paper, we present a new technique for determination of the electron scattering angle based on an accurate measurement of the primary beam energy and the principle of differential nuclear recoil. This technique was used to determine the scattering angle for several experiments carried out at the Experimental Hall A, Jefferson Lab. Results have shown that the new technique greatly improved the accuracy of the angle determination compared to surveys.