Flash Type Research Articles

Low Area and High Bit Resolution Flash Analog to Digital Converter for Wide Band Applications: A Review

: This work reviews the design challenges of CMOS flash type Analog-to-Digital Converter (ADC) for making high bit resolution, low area, low noise, low offset, and power-efficient architecture. Low-bit resolution flash ADC architecture, high-speed applications, and wide-area parallel comparators are identified on their suitability of the design for ADCs. These are effective in the area and bit resolution. The overview includes bit resolution, area, power dissipation, bandwidth and offset noise consideration for high-speed flash ADC design. A MUX-based two-step half flash architecture is considered for applications requiring 1 GHz 16-bit resolution low area and low power consumption. An advanced comparator, MUX, a high-speed digital-to-analog converter (DAC), and MUX-based encoder are also reviewed. The design of technology-efficient ADC architecture is highly challenging for the analog designer.

Rainer Waser – A Pioneer of Fundamentals of Resistive Switching Memories

Rainer Waser – A Pioneer of Fundamentals of Resistive Switching Memories

Adjustment of active protons of end-electron-withdrawing groups in small molecules for different memory characteristics

Owing to the diverse design strategy and convenient structural modification, the small molecular organic materials have been widely applicated in the fabrication of memory devices with complex memory behavior. In this work, we successfully synthesized two asymmetric quinacridone derivatives, BQTCH and BQTCE, with the same electron donors and molecular backbone, but different terminal groups. The sandwich-structured memory devices based on BQTCH and BQTCE have also successfully been prepared via spin-coating. The optical properties, packing performances, thermal stabilities and surface morphologies of the small molecules and their corresponding films are characterized via UV–vis and emission spectra, AFM, TGA and XRD. The I–V curves indicate all the as-prepared devices exhibit excellent memory performances, and the sandwich-structured memory devices based on ITO/BQTCH/Al exhibit a ternary memory behavior (WORM type from OFF to ON1 but FLASH type from ON1 to ON2), while the memory devices based on ITO/BQTCE/Al exhibit a typical ternary memory behavior (WORM type). To explain this difference, DFT molecular simulation and the energy level diagrams of HOMO and LUMO orbitals of BQTCH and BQTCE are investigated to demonstrate the crucial role of terminal groups in influencing the memory behavior.

Abnormal sensation during total body irradiation: a prospective observational study.

Light flash and odor during radiotherapy are well-known phenomena. Two prospective observational studies have indicated that 55% of patients observed a light flash during irradiation of the retina and 27% of patients sensed an odor during radiotherapy for the nasal cavity. A prospective observational study was performed in all patients at our hospital who received total body irradiation (TBI) between January 2019 to October 2021. Light flash and odor during TBI were examined using the same method as that used in previous studies. A total of 32 patients received TBI during the study period. The patients had a median age of 41 (18–60) years, and included 20 males and 12 females. A survey checklist showed that 14 patients (44%) sensed light and 14 patients (44%) sensed odor during TBI,. The color of the light during irradiation was yellow in six cases, white in four cases, and blue in four cases. The intensity of the light was 2–5 (median 3, 1 is very weak, 5 is very strong) and the time over which the light flash was felt was 4–60 s (median 10 s). Two patients each sensed smells of plastic, ozone and bleach, and others sensed one smell each. The intensity of the odor was 1–4 (median 3, 1 is very weak, 5 is very strong) and the time over which the odor was sensed was 1–25 s (median 3 s). We conclude that light flashes and odors are each sensed by 44% of patients during TBI. Various types of light flashes and odors were reported in this study.

Analog synaptic devices applied to spiking neural networks for reinforcement learning applications

In this work, we implement hardware-based spiking neural network (SNN) using the thin-film transistor (TFT)-type flash synaptic devices. A hardware-based SNN architecture with synapse arrays and integrate-and-fire (I&F) neuron circuits is presented for executing reinforcement learning (RL). Two problems were used to evaluate the applicability of the proposed hardware-based SNNs to off-chip RL: the Cart Pole balancing problem and the Rush Hour problem. The neural network was trained using a deep Q-learning algorithm. The proposed hardware-based SNNs using the synapse model with measured characteristics successfully solve the two problems and show high performance, implying that the networks are suitable for executing RL. Furthermore, the effect of variations in non-ideal synaptic devices and neurons on the performance was investigated.

Polymer-Gel Radiation Dosimetry of Laser-Based Relativistic Electron Sources for Biomedical Applications: First Qualitative Results and Experimental Challenges

The generation of laser based relativistic electron sources involves impressive basic science as well as innovative applications. This study reports first novel qualitative results on polymer-gel radiation dosimetry of ultrafast laser-based relativistic electron beams. The fabricated polymer-gels are irradiated by the ultra-high dose rate (FLASH) laser-generated electron beams and then are analysed using magnetic resonance imaging. The reading of the irradiated dosimeters is performed using a clinical 1.5 T Magnetic Resonance Imaging system. Three-dimensional colour parametric T2 maps are then constructed from the original PD-T2 weighted images obtained from the clinical MRI scanner. For comparison, the gels are also irradiated with standard electron beams of various energies utilizing a radiotherapy clinical linear accelerator system. For the calibration measurements of the gel dosimetry method, special calibrated dosimetric films are also implemented. The preliminary results demonstrate the potential of polymer gel dosimetry for 3D-dose-distribution of FLASH type irradiation of laser generated electron beams. Furthermore, they illustrate potential issues related to the polymer gel based dosimetry in challenging irradiation arrangements, such as the oxygen sensitivity and necessity for oxygen impermeable container material.

Selective etching of silicon nitride over silicon oxide using ClF3/H2 remote plasma

Precise and selective removal of silicon nitride (SiNx) over silicon oxide (SiOy) in a oxide/nitride stack is crucial for a current three dimensional NOT-AND type flash memory fabrication process. In this study, fast and selective isotropic etching of SiNx over SiOy has been investigated using a ClF3/H2 remote plasma in an inductively coupled plasma system. The SiNx etch rate over 80 nm/min with the etch selectivity (SiNx over SiOy) of ~ 130 was observed under a ClF3 remote plasma at a room temperature. Furthermore, the addition of H2 to the ClF3 resulted in an increase of etching selectivity over 200 while lowering the etch rate of both oxide and nitride due to the reduction of F radicals in the plasma. The time dependent-etch characteristics of ClF3, ClF3 & H2 remote plasma showed little loading effect during the etching of silicon nitride on oxide/nitride stack wafer with similar etch rate with that of blank nitride wafer.

PRODUKSI KALIMAT DI MEDIA SOSIAL YOUTUBE

This study aims to describe errors in sentence production that focus on two types of errors, quiet and tongue flash. This research is included in the scope of psycholinguistic studies. This research is descriptive qualitative. The data method in this study is the observation method and note-taking technique as advanced methods. After the data is collected, the data is then transcribed autographically and the results are presented in the form of a description. The results of this study were a smile and a tongue glow. Silence is divided into two types namely silent silence and filled silence. The silence that occurs is caused by several things including unpreparedness, forgetfulness, and doubts. Tongue discharge can be due to a variety of things, is rushed, humorous, unconscious, and unfocused.

The influence of camera-trap flash type on the behavioural response, detection rate and individual recognition of Eld’s deer

Context Camera traps are available with infrared or white flash, with the former being more commonly used. However, white flash produces colour night-time photographs that can be critically useful for both species and individual identification. White flash was thought to cause more disturbance to wildlife than was infrared and this may lead to camera avoidance. Evaluating the extent of this response, and differences between the flash types, is useful to develop improved survey designs. Aims This research aimed to quantify the behavioural responses of Eld’s deer to white and infrared flash, to determine whether white-flash cameras were suitable for use in population surveys of this species. Methods A behavioural ethogram was used to quantify the responses of the deer to the two flash types, as well as the responses of different sex-age classes and group sizes when encountering a camera trap. Additionally, the detection rate for white flash and infrared flash cameras was compared through time, to determine any pattern of avoidance. Key results While deer were more likely to observe and be startled by white flash than infrared, this did not adversely affect the detection of the deer, with no significant change in the detection rate between the two different flash types over time. Group size was found not to influence behavioural response when encountering camera traps, whereas different age–sex classes of deer showed very few differences in response to camera traps. Conclusions White flash cameras were found to be suitable for Eld’s deer population surveys and were beneficial in providing colour night-time photos that allow for spotted female deer to be individually identified. Implications Practitioners should not be concerned about the influence of white flash when using camera traps to monitor populations of Eld’s deer, and using white flash is recommended when individual identification is required.

Characterization of Simulator and Relative Spectral Responsivity Measurements of Photovoltaic Modules with Band Pass Filter Technique

One of the most important parameter used for the evaluation of the energy rating of PV modules is, their spectral responsivities which are the measure of electrical performance parameters per incident solar radiation. In this work, spectral responsivity measurements of a mono-crystalline, a poly-crystalline, a CIGS thin film and a bifacial module were measured using xenon-based flash type solar simulator system and a set of band pass filters. For the comprehensive characterization of parameters that may influence the spectral responsivity measurements, initially the simulator system was characterized both optically and thermally according to the IEC60904-9 and IEC60891 standard requirements. The optical characterizations in terms of spectral match, spatial non-uniformity and temporal instability indicate that the measured results (~3.0%, ~0.30% and ~0.20%) according to the IEC 60904-9 standard’s classification requirements correspond to A+A+A+ classes. Moreover, thermal characterizations in terms of the temperature uniformity show that over the 2 × 2 m area temperature uniformity of simulator system’s light distribution (1ºC) is almost two times better than the IEC 60891 standard requirements (±2ºC). Next, PV modules were electrically stabilized according to the IEC 61215-2 standard requirement’s (stability test) to reduce the fluctuations in their electrical performance parameters. Then, using the band pass filters, temperature controlled xenon-based solar simulator system and a reference PV module of the spectral responsivity of PV modules were measured from 400 nm to 1100 nm with 50 nm steps with relative uncertainty of 10-3 level.

Trimetallic AuPtCo Nanopolyhedrons with Peroxidase- and Catalase-Like Catalytic Activity for Glow-Type Chemiluminescence Bioanalysis.

Chemiluminescence (CL) with stable and glowing light emission is vital for the accurate detection of biomarkers. Moreover, the catalyst plays an important role in CL systems. Herein, the trimetallic AuPtCo nanopolyhedrons with peroxidase- and catalase-like catalytic activities are readily synthesized via a one-step reduction method. After reaction with the substrate ABEI and oxidant H2O2, the AuPtCo nanozyme can catalyze the CL emission in a flash type. Interestingly, it has been found that the biofunctionalization of the AuPtCo surface can endow the catalytic interface with a slow-diffusion effect, thereby prolonging the emission of glow-type CL. On this basis, two biofunctionalized AuPtCo nanocomposites, named as AuPtCo@Cys and AuPtCo@Ab, are prepared, achieving sensitive and selective detection of H2O2 and lipoprotein-associated phospholipase A2 (Lp-PLA2), respectively. Further, the proposed glow-type CL assays are successfully applied for the determination of H2O2 and Lp-PLA2 in female vaginal discharge and human serum samples, respectively, which exhibit good correlation with the clinical results. Overall, the trimetallic AuPtCo nanozyme-based glow-type CL analysis has demonstrated as a powerful and robust tool for biomarker analysis, which holds great promise in clinical applications.

Classification of GLM Flashes Using Random Forests

Abstract[The Geostationary Lightning Mapper (GLM) detects total lightning continuously from space, and does not distinguish intra‐cloud (IC) from cloud‐to‐ground (CG) lightning. This research focuses on differentiating CG and IC lightning detected by GLM using a random forests (RF) model. GLM flash and group characteristics are implemented into the RF model and used to predict flash type. The most important flash characteristic for distinguishing flash type is the maximum group area. Other features with high feature importance include time‐of‐day, elongation, propagation, footprint, slope, maximum distance between groups and events, and mean energy. Skill scores showcase the model's ability to distinguish flash type with moderate skill, with 81% probability of detection, 71% percent correct, 36% false alarm rate, 36% false alarm ratio, and 56% critical success index. These scores improve further when study area is limited to CONUS and the Southeastern United States. These results can be used to aid in future climatological analysis of flash type.]

Observations Show Charge Density of Volcanic Plumes is Higher Than Thunderstorms

AbstractWe analyze slow electric field change and lightning mapping measurements to provide insight into the characteristics of volcanic lightning and the associated implications on charging processes and the charge structure of a Vulcanian eruption plume. Data were obtained during a multi‐instrumental field campaign at Sakurajima volcano in 2015 when the Showa crater was active. We combine the electric field change and lightning mapping data from one explosive eruption on June 6, 2015 to identify individual flashes. From this, we interpret the flash type and polarity. In addition, the long‐time constant of the electric field change instrument allowed measurement of the quasi‐static field associated with charge separation in the eruption plume. We find that both intracloud and cloud‐to‐ground discharges occurred, and the polarity of cloud‐to‐ground discharges were all negative. The quasi‐static field measurement showed the plume carried a net negative charge. We calculate both the total charge transferred by cloud‐to‐ground discharges and the net charge density of the eruption plume. We find that cloud‐to‐ground discharges transfer an average of −0.41C per flash and the net charge density was −33C/. The percent error is at least 200%, due to uncertainty in the antenna gain. We show that these estimates are consistent with lightning that is 100 m in length. Further, the average flash rate during the first 8 s following the onset of eruption was five flashes per second. After that time, the flash rate abruptly decreased, which may be related to the end of gas‐thrust forcing.

On-chip trainable hardware-based deep Q-networks approximating a backpropagation algorithm

Reinforcement learning (RL) using deep Q-networks (DQNs) has shown performance beyond the human level in a number of complex problems. In addition, many studies have focused on bio-inspired hardware-based spiking neural networks (SNNs) given the capabilities of these technologies to realize both parallel operation and low power consumption. Here, we propose an on-chip training method for DQNs applicable to hardware-based SNNs. Because the conventional backpropagation (BP) algorithm is approximated, a performance evaluation based on two simple games shows that the proposed system achieves performance similar to that of a software-based system. The proposed training method can minimize memory usage and reduce power consumption and area occupation levels. In particular, for simple problems, the memory dependency can be significantly reduced given that high performance is achieved without using replay memory. Furthermore, we investigate the effect of the nonlinearity characteristics and two types of variation of non-ideal synaptic devices on the performance outcomes. In this work, thin-film transistor (TFT)-type flash memory cells are used as synaptic devices. A simulation is also conducted using fully connected neural network with non-leaky integrated-and-fire (I&F) neurons. The proposed system shows strong immunity to device variations because an on-chip training scheme is adopted.

Key Technology Practice of High-Speed Access and Research on the Temperature Dependence of Key Time Parameters Based on NAND Flash Memory

This paper focuses on the NAND flash memory as a data storage medium in the Internet of things data acquisition system, which plays an important role from beginning to end. The flow process of multi-channel sensor data sampling, holding, conversion, coding, and storage in the data acquisition system is described. The basic working principle and working process of NAND flash memory are introduced. Based on Interleaved Two-plane Program Technology, and the solution of burst massive throughput in high-speed data transmission is proposed. Compared with previously published papers, the temperature dependence of key time parameters of NAND flash memory is studied and analyzed under the condition of temperature change more concretely. The changing trend of three key time parameters of NAND type flash under different temperatures is analyzed by using appropriate test samples. At the same time, the analysis of the causes of reflection from the phenomenon is further expanded and discussed. The combination of theory and practice can provide powerful suggestions for more efficient and accurate application of NAND flash memory.

Thermodynamic Analysis of Multistage Flash Seawater Desalination System

Liu, R.; Zhang, T.; Zhang, H., and Zhao, Q., 2020. Thermodynamic analysis of multistage flash seawater desalination system. In: Hu, C. and Cai, M. (eds.), Geo-informatics and Oceanography. Journal of Coastal Research, Special Issue No. 105, pp. 237–241. Coconut Creek (Florida), ISSN 0749-0208.In this article, the structure of the seawater temperature difference energy multistage flash type seawater desalination system was studied, and the selection of the working medium, the thermodynamic analysis of the circulation system, and the exergy loss of the system were analyzed according to the system structure. The results showed that R134a refrigerants are more suitable to be used as working media in the system. According to the formula of the exergy loss of the circulating system and the flash evaporator, as the temperature of the surface seawater increases, the efficiency of the flash evaporator exergy loss will reduce. Through the analysis of the above-mentioned thermodynamics, a method for improving the energy utilization efficiency of the system can be found.

Geographical personality gradient in herbivorous animals: Implications for selective culling to reduce crop damage

AbstractTraditional lethal techniques used to mitigate wildlife damage have targeted entire populations through the use of random harvesting. However, recent literature has suggested that controlling population size by random harvesting is not the only mean to mitigate human‐wildlife conflicts. Controlling problem individuals may also be important because individuals with behavioral characteristics such as greater boldness and low neophobia are predicted to cause more damage to crops. Reducing the number of bold individuals may therefore mitigate crop damage, but a method to selectively cull bold individuals has not been determined. Hence, this study aimed to demonstrate their distribution in native habitats because if bold and shy individuals prefer different habitats, selective culling could target areas preferred by bold individuals. To detect differences in neophobia (i.e., shyness/boldness), 17 visible flash and invisible infrared flash sensor cameras were randomly placed in forest areas based on the assumption that neophobic (shy) sika deer (Cervus nippon) would be deterred by visible flash cameras (a novel stimulus). The relationship between camera flash type and the probability of detection (i.e., of being photographed by a camera) was used as an index of shyness/boldness. Geographical information system and regression analyses showed that bold individuals preferred forested areas near farmland. These results indicate that selective lethal control could be conducted in forest areas near farmlands to mitigate crop damage.

Time-Correlated Photon Counting for Estimating the Duration of Na-Line and Continuum Emission Flashes in the Spectra of Multi-Bubble Sonoluminescence

The time-correlated photon counting technique using software is used to estimate the duration and succession of Na-line and continuum emission flashes upon irradiation of aqueous solutions of NaCl and Na dodecyl sulfate with ultrasound at a frequency of 20 kHz. The duration of Na flashes was determined as 5.1, 8.0, and 11.7 ns for 5 M NaCl, 0.5 M NaCl, and 5 mM Na dodecyl sulfate solutions, respectively. The duration of a continuum emission flash varied insignificantly within 2.1–2.9 ns for all solutions. The close correlation revealed between the Na-line and continuum emission flashes allows us to conclude that bubbles producing both types of flashes emit them simultaneously with a measured delay of ~0.5 ns for Na.

Novel Protease-Free Long-Lasting Chemiluminescence System Based on the Dox-ABEI Chimeric Magnetic DNA Hydrogel for Ultrasensitive Immunoassay.

Most of chemiluminescence (CL) substrates exhibit the flash-type light emission. Therefore, the long-lasting CL system is always the crown in the field of CL-based analysis methodology. In this work, we constructed a Dox-ABEI chimeric magnetic DNA hydrogel (MDH) as a novel protease-free long-lasting CL reaction system. The functional MDH can transform flash-type ABEI/H2O2/CO2+ reaction into a glow-type CL system because of its block effect on delaying the diffusion rate of co-reactants, making the CL reaction gradually occur. More importantly, the functional MDH possessed the advantages of biocompatibility and controllability and could be well-designed to incorporate different biosensing strategies. Subsequently, we established a functional MDH-based long-lasting CL immunoassay system for ultrasensitive and highly specific detection of d-dimer and fibrin degradation products (FDPs). The designed CL immunoassay can detect d-dimer and FDP down to 53.7 and 31.6 fg/mL, respectively, with a wide line ranging from 100 fg/mL to 100 ng/mL, which was superior to the previously reported CL biosensing strategies. Moreover, benefiting from the magnetic separation of MDH and excellent CL performance, the developed immunoassaying method was successfully applied in the detection of clinical samples, which showed a close correlation with clinical reference technology. Thus, this functional MDH proved to be an excellent long-lasting CL system and a potential technical platform for clinical bioanalysis applications.

Multiscale computational fluid dynamics modeling and reactor design of plasma-enhanced atomic layer deposition

Plasma-enhanced atomic layer deposition (PEALD) is one of the most widely adopted deposition methods in the semiconductor industry. It is chosen largely due to its superior ability to deliver ultra-conformal dielectric thin-films with high aspect-ratio surface structures, which are encountered more and more often in the novel design of metal-oxide-semiconductor field-effect transistors (MOSFETs) in the NAND (Not-And)-type flash memory devices. Compared with the traditional thermal ALD method, PEALD allows for lower operating temperature and speeds up the deposition process with the involvement of plasma species. Despite its popularity, the development of PEALD operation policies remains a complicated and expensive task, which motivates the construction of an accurate and comprehensive simulation model. While existing models have described the individual or partially coupled domains, none of these models has captured all three domains in the PEALD process: surface reaction, macroscopic gas transport, and plasma generation. In this work, a comprehensive multiscale computational fluid dynamics (CFD) model is developed for a remote PEALD reactor used in the deposition of HfO2 thin-films. First, a previously developed kinetic Monte-Carlo (kMC) model is adapted for the multiscale simulation to describe the surface reactions. Then, two macroscopic models, specifically tailored for the remote plasma reactor, are formulated to describe the dynamic behaviors of the plasma generation and bulk species transport domains, respectively. Additionally, an integrated message passing interface (MPI) scheme is built to couple and resolve the communication between different scales in the model. The model results are then validated with experimental data and an automated workflow is established for model calculations without human intervention. Finally, a set of baseline operating conditions derived from the model simulation results is proposed to guarantee the production of high-quality thin-films.