Digitization Scheme Research Articles

Analyzing One- and Two-bit Data to Reduce Memory Requirements for F -statistic-based Gravitational Wave Searches

Searches for continuous-wave gravitational radiation in data collected by modern long-baseline interferometers, such as the Laser Interferometer Gravitational-wave Observatory (LIGO), the Virgo interferometer, and the Kamioka Gravitational Wave Detector, can be memory intensive. A digitization scheme is described that reduces the 64-bit interferometer output to a one- or two-bit data stream while minimizing distortion and achieving considerable reduction in storage and input/output cost. For the representative example of the coherent, maximum-likelihood matched filter known as the F -statistic, it is found using Monte Carlo simulations that the injected signal only needs to be ≈24% stronger (for one-bit data) and ≈6.4% stronger (for two-bit data with optimal thresholds) than a 64-bit signal in order to be detected with 90% probability in Gaussian noise. The foregoing percentages do not change significantly when the signal frequency decreases secularly, or when the noise statistics are not Gaussian, as verified with LIGO Science Run 6 data.

Digitizing lattice gauge theories in the magnetic basis: reducing the breaking of the fundamental commutation relations

We present a digitization scheme for the lattice SU(2)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\ extrm{SU}}(2)$$\\end{document} gauge theory Hamiltonian in the magnetic basis, where the gauge links are unitary and diagonal. The digitization is obtained from a particular partitioning of the SU(2)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\ extrm{SU}}(2)$$\\end{document} group manifold, with the canonical momenta constructed by an approximation of the Lie derivatives on this partitioning. This construction, analogous to a discrete Fourier transform, preserves the spectrum of the electric part of the Hamiltonian and the canonical commutation relations exactly on a subspace of the truncated Hilbert space, while the residual subspace can be projected above the cutoff of the theory.

CUSTOMER SATISFACTION OF GOOGLE PAY UPI PAYMENT APPS

Digitization and Go cashless scheme has been extensively pushed by the Indian government to regularize and smoothen the cash transaction after demonetization. The demonetization consequences give extraordinary growth in digital payment such as E-banking, Mobile banking, Card transaction etc. Unified Payments Interface (UPI) is one of the fastest growing digital payment system through which a user can both send and receive money through a Virtual Payment Address (VPA). Uniqueness of UPI over other digital payment methods like 24*7 and 365 days availability, Easy and convenient to use and secure gateway attracts the customers of service sector. This research was mainly focused to study the customer perception (service sector) towards the awareness and adoption of UPI systems in Indore region. For this research primary data was collected through structured Questionnaire contains 5 point likert scale from service sector and secondary Data collected from Government Reports, Website etc. This research concludes with aspects of awareness and adoption of UPI through comparison between gender, age and occupational data of customers. The results of this study add to our knowledge about acceptation of UPI and its usefulness in cashless and immediate transactions that influence young male customers who belongs to service sectors. The research concluded that customer of service sector is more swing towards the adoption of UPI and there is significant difference found male and female customers towards the adoption and use of UPI.

Development of a self-powered digital LAMP microfluidic chip (SP-dChip) for the detection of emerging viruses.

Point-of-care (POC) diagnostics have emerged as a crucial technology for emerging pathogen detections to enable rapid and on-site detection of infectious diseases. However, current POC devices often suffer from limited sensitivity with poor reliability to provide quantitative readouts. In this paper, we present a self-powered digital loop-mediated isothermal amplification (dLAMP) microfluidic chip (SP-dChip) for the rapid and quantitative detection of nucleic acids. The SP-dChip utilizes a vacuum lung design to passively digitize samples into individual nanoliter wells for high-throughput analysis. The superior digitization scheme is further combined with reverse transcription loop-mediated isothermal amplification (RT-LAMP) to demonstrate dLAMP detection of Zika virus (ZIKV). Firstly, the LAMP assay is loaded into the chip and passively digitized into individual wells. Mineral oil is then pipetted through the chip to differentiate each well as an individual reactor. The chip did not require any external pumping or power input for rapid and reliable results to detect ZIKA RNA as low as 100 copies per μL within one hour. As such, this SP-dChip offers a new class of solutions for truly affordable, portable, and quantitative POC detections for emerging viruses.

Cave feature extraction and classification from rockery point clouds acquired with handheld laser scanners

Rockeries are unique elements of Chinese classical gardens with historical, cultural, artistic, and scientific value. One of the essential characteristics of garden rockery is the cave features since cave morphological features determine the degree of “Tou” (riddled through) and “Lou” (hollowed out well) features as the defined by rockery appreciation theory, which is important for rockery heritage conservation, assessment, and management. However, in heritage studies, accurately identifying and evaluating rockery caves is a difficult task because of a cave's irregular shape. This paper proposes a methodology to extract and classify cave features by point clouds obtained from data using a handheld laser scanner with a camera. Without completing surface reconstruction, the rockery point cloud is first sliced into chips, then cave chips were extracted from these approximately two-dimensional chips and next merged to obtain three-dimensional cave point clouds. Finally, the cave boundary points are extracted from the cave and fitted by an ellipse for classification. To extract and classify cave features, a methodology to improve rockery digitalization quality is also proposed. The raw point cloud data were preprocessed by pose adjustment, noise removal, and hole repair. The experimental results for the two rockeries in Tongji University and Qiuxiapu Garden indicate that the improved digitization scheme generates complete and closed rockery point clouds, all types of caves were effectively extracted and classified by our proposed method. Additionally, the extracted caves are still represented by point clouds, which suggest the possibility for other research in the future.

Social Media Marketing and TOE Framework Exploration in Digital Micro or Small and Medium Enterprises

This article aims to determine the function and role of digital MSMEs stands for Micro or Small-Medium Enterprises using TOE exploration during the Covid-19 pandemic. The Covid-19 pandemic has made the majority of the economic sector, especially MSMEs, decline. The majority of MSMEs actors cannot develop and many ended up in bankruptcy. This is what makes MSMEs business actors change the function and role of digital MSMEs during the COVID-19 pandemic with a sales strategy through a digitalization scheme. The digitization scheme is by utilizing a market place (intermediary) and using social media as a marketing technique. In addition, digital MSMEs actors must be able to synergize with consumers in marketing products and services. Thus the digital MSMEs development scheme can be an alternative to save business actors in the midst of the Covid-19 pandemic. This article uses the literature study method by elaborating various literatures on the development of digital MSMEs. This article argues that the development of digital MSMEs has become an alternative to saving as well as developing the functions and roles of digital MSMEs during the COVID-19 pandemic.

Stationary scattering solution and logic operations in X-coupled tight-binding chains

The realization of logical operations on X-shaped structures consisting of two discrete input chains, which are linearly connected to two output chains through a central coupling region, is investigated. We provide the exact stationary scattering solution for the harmonic waves propagating in the proposed structure and report the full transmission spectrum. We show that a number of Boolean logic operations can be implemented using a digitization scheme of the output signal based on the amplitude modulation of the transmission coefficients. In particular, we show that the relative phase between input harmonics can be used as a control parameter to select the desired logic operation. A detailed study of the contrast ratio is used to identify optimal regions in the parameter space for the operation of each logical function.

Spectrum of digitized QCD: Glueballs in a S(1080) gauge theory

Quantum simulations of QCD require digitization of the infinite-dimensional gluon field. Schemes for doing this with the minimum amount of qubits are desirable. We present a practical digitization for $SU(3)$ gauge theories via its discrete subgroup $S(1080)$. Using a modified action that allows classical simulations down to $a\ensuremath{\approx}0.08\text{ }\text{ }\mathrm{fm}$, the low-lying glueball spectrum is computed with percent-level precision at multiple lattice spacings and is shown to extrapolate to the continuum limit $SU(3)$ results. This suggests that this digitization scheme is sufficient for precision quantum simulations of QCD.

An SNR-improved Transmitter of Delta-sigma Modulation Supported Ultra-High-Order QAM Signal for Fronthaul/WiFi Applications

In this paper, we proposed an improved mobile fronthaul architecture employing the SNR-improved delta-sigma digitization scheme and 4-level pulse amplitude modulation (PAM-4) format. Different from traditional 2-bit quantization, this scheme deploys two-fold delta-sigma quantization, which uses 1-bit delta-sigma modulator to quantize the signal, and another 1-bit delta-sigma modulator to quantize the in-band noise. A significant reduction of the in-band noise can be achieved only applying a differentiator, bringing about a much better noise shaping performance. Meanwhile, the two 1-bit streams can be combined and transmitted in a PAM-4 manner through an intensity modulation direct detection (IM-DD) channel. We have successfully experimentally demonstrated the digitization and transmission of 65536 quadrature amplitude modulation (QAM) baseband orthogonal frequency division multiplexing (OFDM) signal with sampling rate of 1.25 GSa/s over 20-km fiber with standard 10-Gbaud PAM-4 signal, with a signal to noise ratio (SNR) of 57.7 dB. Compared to the conventional 2-bit quantized OFDM scheme, experimental results show that a significant SNR improvement of 17.7 dB has been achieved by the proposed scheme. In addition, we also realized a transmission of 16384-QAM intermediate frequency (IF) signal at the center frequency of 3.5 GHz (with an SNR of 49.6 dB). An improvement of 15.9 dB can also be maintained.

ONLINE BUSINESS TRANSFORMATION IN THE COVID-19 PANDEMIC ERA (CASE STUDY OF MSME ACTIVITIES IN TANGERANG CITY)

This study aims to find out how the online business transformation in Micro, Small and Medium Enterprises (MSMEs) during the Covid-19 pandemic. The Covid-19 pandemic has made the majority of economic sectors, especially MSMEs stagnant. The majority of MSME actors cannot develop and many end up in bankruptcy. This is what makes MSME business actors change their sales strategy through digitalization schemes. The digitization scheme is by utilizing a marketplace (intermediary) and using social media as a marketing technique. In addition, digital MSME actors must be able to synergize with netizens in marketing products and services. Thus, the digital MSME development scheme can be an alternative to saving business actors in the midst of the Covid-19 pandemic. This research uses descriptive qualitative method. The formulation of the problem in the research is: how MSMEs adapt to the online business transformation in the era of the Covid-19 pandemic, the impact of MSME turnover on the Covid-19 pandemic, and how big the impact of the COVID-19 The pandemic is on the MSME workforce. This study argues that the development of digital MSMEs has become an alternative to saving as well as developing digital entrepreneurship in Indonesia during the Covid-19 pandemic

Monte Carlo evaluation of hypothetical long axial field-of-view PET scanner using GE Discovery MI PET front-end architecture.

The development of total-body PET scanners is of growing interest in the PET community. Investigation into the imaging properties of a hypothetical extended axial field-of-view (AFOV) GE Healthcare SiPM-based Discovery MI (DMI) system architecture has not yet been performed. In this work, we assessed its potential as a whole-body scanner using Monte Carlo simulations. The aim of this work was to (1) develop and validate a Monte Carlo model of a four-ring scanner and (2) extend its AFOV up to 2m to evaluate performance gain through NEMA-based evaluation. The DMI four-ring geometry and its pulse digitization scheme were modeled within the GATE Monte Carlo platform using published literature. The GATE scanner model was validated by comparing results against published NEMA performance measurements. Following the validation of the four-ring model, the model was extended to simulate 8-, 20-, 30-, and 40-ring systems. Spatial resolution, sensitivity, NECR, and scatter fraction were characterized with modified NEMA NU-2 2018 standards; however, the image quality measurements were not acquired due to computational limitations. Spatial resolutions were simulated for all scanner ring configurations using point sources to examine the effects of parallax errors. NEMA count rates were estimated using a standard 70cm scatter phantom and an extended version of scatter phantom of length 200cm with (1-800) MBq of 18 F for all scanners. Sensitivity was evaluated using NEMA methods with a 70cm standard and a 200cm long line source. The average FWHM of the radial/tangential/axial spatial resolution reconstructed with filtered back-projection at 1 and 10cm from the scanner center were 3.94/4.10/4.41mm and 5.29/4.89/5.90mm for the four-ring scanner. Sensitivity was determined to be 14.86cps/kBq at the center of the FOV for the four-ring scanner using a 70cm line source. Sensitivity enhancement up to 21-fold and 60-fold were observed for 1 and 2m AFOV scanners compared to four-ring scanner using a 200cm long line source. Spatial resolution simulations in a 2m AFOV scanner suggest a maximum degradation of ∼23.8% in the axial resolution compared to the four-ring scanner. However, the transverse resolution was found to be relatively constant when increasing the axial acceptance angle up to ±70°. The peak NECR was 212.92 kcps at 22.70 kBq/ml with a scatter fraction of 38.9% for a four-ring scanner with a 70cm scatter phantom. Comparison of peak NECR using the 200cm long scatter phantom relative to the four-ring scanner resulted in a NECR gain of 15 for the 20-ring and 28 for the 40-ring geometry. Spatial resolution, sensitivity, and scatter fraction showed an agreement within ∼7% compared with published measured values. The four-ring DMI scanner simulation was successfully validated against published NEMA measurements. Sensitivity and NECR performance of extended 1 and 2 m AFOV scanners based upon the DMI architecture were subsequently simulated. Increases in sensitivity and count-rate performance are consistent with prior simulation studies utilizing extensions of the Siemens mCT architecture and published NEMA measurements with the uEXPLORER system.

Development of synergistic between digitalization MSMEs and digital society in Indonesia

This article aims to elaborate on Micro, Small, and Medium Enterprises (MSMEs) and the Digital Society during the Covid-19 pandemic in Indonesia. The Covid-19 pandemic has paralyzed most sectors of the economy, especially micro-enterprises. The profits of most MSME actors did not increase, and many went bankrupt. That is why MSME business actors change their sales strategy with digitalization schemes. The digitization scheme is to use the marketplace as an intermediary and social media as a marketing technique. In addition, digital MSME actors must synergize with the digital community in marketing products and services. Therefore, the SME digital development initiative can be an alternative to saving business actors during the Covid-19 pandemic. This article uses a literature study with a library research method approach by elaborating various literature on the development of digital SMEs. Twenty-five articles were reviewed in this study from Sinta (Science and Technology Index) and Google Scholar. The paper argues that the development of digital MSMEs has become an alternative to saving and developing digital entrepreneurship in Indonesia during the Covid-19 pandemic.

A Photonic Digitization Scheme With Enhanced Bit Resolution Based on Hierarchical Quantization

The major limitation of the photonic digitization schemes based on the phase-shifting of modulation transfer function lies in its relatively low bit resolution, which is log 2 (2N ), where N is the number of optical channels or modulators. In this paper, we propose a novel photonic digitization scheme based on hierarchical quantization, which could greatly improve the system resolution with a relatively simple configuration. It is shown that 6N quantization levels, can be realized by using only three Mach-Zehnder modulators (MZMs) and a hierarchical quantization module (HQM) in the proposed scheme. By adjusting the fine quantization module inside HQM, the system resolution can be enhanced greatly. A proof-of-concept experiment is implemented, which fully verifies the correctness of the approach. Since simpler configuration and higher resolution are achieved, the proposed scheme provides a promising solution for high-performance photonic analog-to-digital conversion.

Gluon field digitization for quantum computers

Simulations of gauge theories on quantum computers require the digitization of continuous field variables. Digitization schemes that uses the minimum amount of qubits are desirable. We present a practical scheme for digitizing $SU(3)$ gauge theories via its discrete subgroup $S(1080)$. The $S(1080)$ standard Wilson action cannot be used since a phase transition occurs as the coupling is decreased, well before the scaling regime. We proposed a modified action that allows simulations in the scaling window and carry out classical Monte Carlo calculations down to lattice spacings of order $a\approx 0.08$ fm. We compute a set of observables with sub-percent precision at multiple lattice spacings and show that the continuum extrapolated value agrees with the full $SU(3)$ results. This suggests that this digitization scheme provides sufficient precision for NISQ-era QCD simulations.

Photonic Digitization With Differential Encoding Based on Orthogonal Vector Superposition

In this paper a novel photonic digitization scheme with differential encoding based on orthogonal vector superposition (OVS) is proposed and demonstrated. A phase modulator (PM) and two delay-line interferometers (DLIs) with π/2 difference in bias phase are employed to generate two orthogonal modulated signals. By adjusting and combining the intensity of two orthogonal signals with an OVS module, the desired phase shifts among different transfer functions can be obtained. The proposed scheme can differentially encode the input signal with enhanced bit resolution. Compared with the existing photonic digitization schemes based on modulators, this scheme features its simple configuration, because only a single PM, two DLIs and an OVS module are required; moreover, since the desired phase shifts of transfer functions are realized by attenuating the signal intensities, the proposed scheme can effectively alleviate the problem of phase bias drift induced by modulators. Proof-of-concept experiments of 3- and 4-bit photonic digitization systems based on OVS are successfully carried out, which demonstrate the feasibility of the approach.

ASTRONIRCAM—the infrared camera-spectrograph for the 2.5-m telescope of SAI Caucasian observatory

ASTRONIRCAM is a cryogenic-cooled slit spectrograph for the spectral range 1-2.5 mkm installed at the Nasmyth focus of the 2.5-meter telescope of the Caucasian observatory of Sternberg Astronomical Institute of Lomonosov Moscow State University. The instrument is equipped with the HAWAII-2RG 2048x2048 HgCdTe array. Grisms are used as dispersive elements. In the photometric mode ASTRONIRCAM allows for extended astronomical object imaging in the field of view of 4.6x4.6 arc minutes with the 0.269 arcsec/pixel scale in standard photometric bands J, H, K and Ks as well as in narrow-band filters CH_4, [Fe II], H_2 v=1-0 S(1), Br_gamma and CO. In the spectroscopic mode, ASTRONIRCAM takes spectra of extended or point-like sources with spectral resolution R=lambda/Delta lambda <= 1200. The general design, optical system, detector electronics and readout, amplification and digitization scheme are considered. The conversion factor GAIN measurement results are described as well as its dependence on the accumulated signal (non-linearity). The full transmission of the atmosphere-to-detector train ranges from 40 to 50\% in the wide-band photometry mode. The ASTRONIRCAM sensitivity at the 2.5-m telescope is characterized by the limiting J=20, K=19 star magnitudes measured with the 10% precision and 15 minutes integration at the 1 arcsec atmospheric seeing conditions. The references to first results published on the base of ASTRONIRCAM observations are given.

A digitization scheme of sub-microampere current using a commercial comparator with hysteresis and FPGA-based wave union TDC

A digitization scheme of sub-microampere current using a commercial comparator with adjustable hysteresis and FPGA-based Wave Union TDC has been tested. The comparator plus a few passive components forms a current controlled oscillator and the input current is sent into the hysteresis control pin. The input current is converted into the transition times of the oscillations, which are digitized with a Wave Union TDC in FPGA and the variation of the transition times reflects the variation of the input current. Preliminary tests show that input charges < 25 fC can be measured at > 50 M samples/s without a preamplifier.

A General Analysis of the Impact of Digitization in Microwave Correlation Radiometers

This study provides a general framework to analyze the effects on correlation radiometers of a generic quantization scheme and sampling process. It reviews, unifies and expands several previous works that focused on these effects separately. In addition, it provides a general theoretical background that allows analyzing any digitization scheme including any number of quantization levels, irregular quantization steps, gain compression, clipping, jitter and skew effects of the sampling period.

Digitization scheme that assures faithful reconstruction of plane figures

In the present extensive work, we propose a digitization scheme for a broad class of plane figures. It includes arbitrary polygons (possibly, non-convex and with holes) and plane sets whose boundary consists of smooth curves or straight segments. Our approach is based on an appropriate scaling of the original continuous real object so that the obtained magnified object and its (appropriately constructed) digitization feature analogous geometric properties. As a bi-product of the presented theory we prove the strong NP-hardness of the problem of obtaining an optimal (i.e., with a minimal number of facets) polyhedral reconstruction in which the facets are trapezoids or triangles. This result implies the strong NP-hardness of the general polyhedral reconstruction problem, which was a long-standing open problem. As another major result, we show that the proposed digitization scheme allows faithful reconstruction of plane figures from the considered general class. The reconstructed set features the basic properties of the original object, such as location of curve and straight segments and inflection points of its boundary.

Improving the accuracy of isotropic granulometries

Morphological sieves are capable of classifying objects in images according to their size. They yield a granulometry, which describes the imaged structure. The discrete sieve has some disadvantages that its continuous-domain counterpart does not have: sampled disks (used as isotropic structuring elements) are rather anisotropic, especially at small scales, and their area, as a function of the size in the continuous domain, shows jumps at apparently arbitrary locations. These problems cause a severe bias and low precision of the derived size distribution. Therefore we propose a new digitization scheme for implementing continuous sieves. First we increase the sampling density of the structuring element and the image. This does not add new detail to the image, but yields a sampled structuring element that is a much better approximation to its continuous counterpart, and thereby substantially reduces the discretization error. The second innovation is to shift the structuring element with respect to the sampling grid; this makes the size increments smoother, and further reduces the discretization errors. These ideas are validated on synthetic images. We also show that the proposed improvements allow for a finer scale sampling.