Single Module Research Articles

Enhanced ARIA-based counter mode deterministic random bit generator random number generator implemented in verilog

This paper presents a study aimed at effectively implementing a deterministic random bit generator (DRBG) IP in verilog language, based on the standard encryption algorithm. By controlling the existing round generation and key generation blocks, the internal modules of the counter mode deterministic random bit generator (CTR-DRBG) were successfully implemented and operated, ensuring the secure and efficient generation of random bit sequences. The research focused on parallel operation of modules and optimized module placement to achieve improved clock frequencies. By concurrently operating two modules in the derivation and internal update modules of CTR-DRBG, the processing speed was enhanced compared to the conventional algorithm. Additionally, integrating the reseeding and initialization modules of CTR-DRBG into a single module successfully reduced size. Furthermore, this IP supports the special function register (SFR) interface. The safety of the CTR-DRBG was validated through known answer test (KAT) verification utilizing test vectors from certification. Future research should explore additional studies on CTR-DRBG operating on real FPGA or ASIC, not only using normal algorithm but also employing other block cipher algorithms.

An advanced solid-state RF power source maximizing energy efficiency for optimal superconducting RF cavity charging

Abstract This paper outlines an experimental demonstration of an envelope tracking (ET) technique applied to a kilowatt-level single-ended solid-state power amplifier (SSPA), aimed at enhancing the charging efficiency of superconducting radio frequency (SRF) cavities by reducing reflection power while maintaining a high degree of efficiency. The technique is particularly designed for the pulsed operation of the European Spallation Source (ESS) at a nominal frequency of 352 MHz, with a 5% duty cycle and a pulse width of 3.5 ms. The study introduces an optimal charging scheme using a solid-state-based amplifier to maintain high efficiency, allowing for power ramp-up while minimizing reflections from SRF cavities and optimizing SSPA efficiency. A fast envelope tracking power supply (ETPS) system is implemented for the approximately 300 ms charging time required by the SRF cavities at ESS. The ETPS system, demonstrated on a single module as a proof-of-concept with scalability potential to a 400 kW power station, indicates an overall average efficiency of 70% and a 24% energy saving over traditional vacuum-tube based amplifiers. This demonstrates the ET technique’s effectiveness at the kilowatt level for efficient SRF cavity charging with reduced reflection, offering significant efficiency and energy savings.

Probable Autoimmune Lymphoproliferative Syndrome with Monogenic Lupus Due to KRAS Mutation.

Autoimmune lymphoproliferative syndrome (ALPS) is a disease characterized by dysfunction of the T lymphocyte apoptotic pathways, mostly due to dysfunctional FAS mediated signaling. However few cases can also occur independent of FAS pathway alteration. ALPS is characterized by various immuno-hematological manifestations. Monogenic lupus is an evolving entity, which describes the etiologic role of single gene modulation in systemic lupus erythematosus. In this manuscript, we describe a case of probable ALPS with monogenic lupus caused by a novel mutation in the KRAS gene.

Cascaded Multi-Input Single-Output Boost Inverter for Mismatch Mitigation at PV Submodule Level

Mismatched power generation is a serious issue in PV systems, resulting from unequal power generation between PV components. Solutions have been proposed to reduce or eliminate the mismatch concern. One practical strategy is individually harvesting the maximum power from each PV component; the more distributed MPPT is applied to a finer level, the more power can be obtained. This study proposes three-input single-output boost converters that are employed to effectively increase PV power generation and significantly reduce mismatch issues between the PV submodule (PV SM). Each boost converter will be controlled to harvest the maximum power from a group of PV cells inside a single PV module. The outputs of the three boost converters are connected in series to provide higher output voltage for grid integration. The cascaded power converters are linked with a forwarding diode to provide a protection feature for the system and prevent the reverse current from harming the PV module. On the grid side, a single-phase Voltage Source Inverter (VSI) is used to convert the DC power from the PV module to sinusoidal AC power. The performance of the suggested inverter has been confirmed through experimental tests.

Eight-channel integrated device for electro-optic modulation and dense wavelength division multiplexing based on photonic crystals

We propose an eight-channel integrated device for electro-optic modulation and dense wavelength division multiplexing based on photonic crystals. The device consists of eight photonic crystal AAH cavities and eight reflection cavity filters to contribute a modulation module and a dense wavelength division multiplexing module, respectively. First, the physical model of the eight-channel integrated device is established, and then modeling and analyzing the transmission performance of the single channel modulator according to the coupled mode theory. The parameters of the proposed device are calculated by two dimensional finite-difference time-domain method for verification. The numerical results shows that the minimum insertion loss, channel crosstalk in the “on” state are 0.24 dB and −17.8 dB, respectively, and the extinction ratio in the “off” state is higher than 19.3 dB. The designed eight-channel integrated device has the advantages of low loss, small size (114.81×16×0.22)μm3 and easy cascading structure, which can realized “on” and “off” modulation with channel space of 0.8 nm, dense wavelength division multiplexing function in the operating wavelength range of 1552.8 nm–1558.4 nm and applied in data center and highly integrated optical communication system.

A long-reach radio over free space optics (Ro-FSO) system using hybrid orthogonal frequency division multiplexing (OFDM)-multibeam concept with enhanced detection

Abstract This paper focuses on designing of a 10 Gbit/s-10GHz hybrid Orthogonal frequency division multiplexing (FDM) based Radio over Free Space Optics (Ro-FSO) transmission link using optical single sideband modulation format and its performance has been compared using a different number of transmission beams. The proposed link has been simulated and compared using 1-beam, 2-beam, and 4-beam in the system. We show that by using the 4-beam system in the OFDM-Ro-FSO link, a 3000 m range has been achieved reliably, which a notable improvement when compared to previous work is. Also, we show an improved performance of the system by using an enhanced detection mechanism using a Square root module (SRm) at the receiver side.

Modeling of Integrated Hollow-Fiber Solar-Powered VMD Modules for Desalination for a Better Understanding and Management of Heat Flows.

The direct integration of membrane distillation and solar energy collection in a single module is a promising technology for autonomous seawater desalination in remote regions; however, the modeling and design of such modules are challenging because of the coupling of the radial and longitudinal heat and mass transfers. In a previous study, we provided as a first modeling approach a hollow fiber solar collector vacuum membrane distillation (VMD) module, considering a constant temperature at the shell side and a pure water feed. Here, a full model is developed to describe the coupled effects of the solar collector and a hollow fiber VMD module operating in an outside/in mode with saline water. The model considers all the main phenomena (membrane distillation, temperature and concentration polarization, absorption of solar radiation and energy balances over the solar collector, radial and longitudinal heat and mass transfer, seawater properties, and more than 30 variables). Applied to simulate the behavior of a semi-industrial-scale module, it allows the influence of solar radiation on the performance/limits of the integrated module to be discussed based on the radial and longitudinal profiles and heat flows. The model can be used to identify key points in the module design to better utilize solar radiation and manage heat flows.

Scalable all‐perovskite double‐ and triple‐junction solar modules: Modeling for configuration optimization

AbstractWe modeled the photovoltaic conversion of all‐perovskite (PVK) double‐ and triple‐junction solar modules to clarify the configurations suitable for the monolithically series‐interconnected structure, which offers high scalability by fully exploiting the advantages of the thin‐film modules over wafer‐based crystalline‐silicon modules. We first formulated the photovoltaic processes of single cells and modules by reference to previously reported data, next optimized the module structure parameters including the bandgaps of PVKs, cell widths, and transparent‐electrode thicknesses, and then evaluated the annually averaged conversion efficiencies (ηannual) defined by the ratio of the annual energy yield to the annual insolation in outdoor environments using a meteorological database. The double‐junction four‐terminal (2J‐4T) module overcomes the shortcomings involved in the two‐terminal module consisting of series‐connected top and bottom cells, providing higher ηannual and more options of the top‐cell bandgap; the latter allows us to select a more durable PVK composition. However, the dual output (four terminals) is practically a serious drawback. The double‐junction voltage‐matched (2J‐VM) configuration eliminates this drawback, that is, realizes the single output (two terminals) with taking over the advantages of 2J‐4T, and hence, 2J‐VM would be the most promising candidate. However, when the VM configuration is applied to the triple‐junction modules, the ohmic loss and optical loss in the transparent electrodes used for the three submodules are more detrimental. To mitigate this shortcoming, we proposed a new configuration of the triple‐junction series/parallel‐connecting voltage‐matched (3J‐SPVM) module. This uses only two substrates with securing high ηannual and other advantages of the VM configuration, which contributes to cost reduction. Consequently, 3J‐SPVM is potentially the most promising configuration for widespread use.

Elastic energy trapping in Kresling origami

In this study, elastic energy trapping strategy is exploited to investigate the energy absorption capability of origami structures. The twofold novelty of this paper can be summarized as (i) comprehensive analysis of a single Kresling module from a geometrical point of view to illustrate its energy trapping capability in the pathway of compression; (ii) introducing translational and torsional ACKS (achiral coupled Kresling structures); demonstrating their potential to be utilized as a platform for designing energy absorption systems that can trap energy applied by compressional and torsional loads. The outcomes pave the way toward utilizing origami structures in reusable energy-absorbing systems.

Effect of flux and shear rate on E. coli recovery in tangential flow filtration through a single hollow fiber.

Pathogenic bacteria which enter a viable but non-culturable (VBNC) state impede efforts to reach detectable concentrations required for PCR methods. This motivated a strategy for tangential flow filtration to concentrate bacteria in aqueous samples while maintaining the bacteria in a viable state, maximizing their recovery and achieving high fluxes through a single hollow fiber membrane. Filtrations were carried out for green fluorescent protein (GFP) E. coli at high shear rates (up to 27,000 sec-1) through 0.2 μm cut-off polyethersulfone (PES) microfilter membranes or 50 kDa polysulfone (PS) ultrafilter membranes. High shear minimized bacterial attachment on membrane surfaces, which would otherwise occur due to forced convection of the particles to the membrane surface at high flux conditions. Single fiber filter modules were constructed to facilitate concentration of Escherichia coli at fluxes ranging from 55 to 4500 L m-2 h-1. The effect of high shear rates on bacterial viability was found to be minimal with bacterial losses during filtration caused principally by their accumulation on the membrane surface. Recoveries of 90% were achievable at high shear rates when the average flux was ≤300 L m-2 h-1. This corresponded to a 3-h filtration time for a 225 mL sample through a single hollow fiber. Detectable bacteria concentrations of 1800 colony-forming unit (CFU)/mL were achieved for starting concentrations of 140 CFU/mL.

The first crystal structure of a family 45 glycoside hydrolase from a brown-rot fungus, Gloeophyllum trabeum GtCel45A.

Here we describe the first crystal structure of a beta-1,4-endoglucanase from a brown-rot fungus, Gloeophyllum trabeum GtCel45A, which belongs to subfamily C of glycoside hydrolase family 45 (GH45). GtCel45A is ~ 18 kDa in size and the crystal structure contains 179 amino acids. The structure is refined at 1.30 Å resolution and Rfree 0.18. The enzyme consists of a single catalytic module folded into a six-stranded double-psi beta-barrel domain surrounded by long loops. GtCel45A is very similar in sequence (82% identity) and structure to PcCel45A from the white-rot fungus Phanerochaete chrysosporium. Surprisingly though, initial hydrolysis of barley beta-glucan was almost twice as fast in GtCel45A as compared to PcCel45A.

A Single Sampling Double Update Modulation Method to Enhance Low-Carrier Ratio Operation

A Single Sampling Double Update Modulation Method to Enhance Low-Carrier Ratio Operation

A High-Power-Density Quasi-Resonant Switched-Capacitor DC–DC Converter With Single Semiperiod Tank Current Modulation

A High-Power-Density Quasi-Resonant Switched-Capacitor DC–DC Converter With Single Semiperiod Tank Current Modulation

Multibody Analysis of Wave Energy Converters and a Floating Platform in the Time Domain

Generally, new and renewable energy systems generate electricity by installing and operating multiple modules simultaneously. In the Republic of Korea, recent studies and developments have focused on asymmetric wave energy converters (hereafter referred to as rotors) suitable for marine environments off the western coast of Jeju. These rotors are arranged on a large floating truss-structure platform and designed to harness electricity from the rotors’ pitch motion. However, when multiple rotors operate on a platform, their behavior diverges from that of a single module due to hydrodynamic interactions between them. Moreover, because the rotors are connected to the floating platform, their motion is influenced by the platform’s dynamics. In this study, a time-domain multibody motion equation was established to analyze changes in the behavioral characteristics of the rotors, both with and without a floating platform. The hydrostatic and hydrodynamic coefficients were derived in the frequency domain using WAMIT, a commercial code based on linear potential flow theory for three-dimensional diffraction/radiation analyses. The motion equation was then applied under regular and irregular wave conditions using OrcaFlex version 11.3, a marine systems design and analysis program. The resulting behaviors were compared to elucidate the influence of the platform and hydrodynamic interactions on the rotors’ performance.

Multimodal deep fusion model based on Transformer and multi-layer residuals for assessing the competitiveness of weeds in farmland ecosystems

Weed competitiveness monitoring is crucial for field management at specific locations. Recent research in the fusion of multimodal data from unmanned aerial vehicles (UAVs) has propelled this advancement. However, these studies merely stack extracted features equivalently, neglecting the full utilization of fused information. This study utilizes hyperspectral and LiDAR data collected by UAVs to proposes a multimodal deep fusion model (MulDFNet) using Transformer and multi-layer residuals. It utilizes a comprehensive competitive index (CCI-A) based on multidimensional phenotypes of maize to assess the competitiveness of weeds in farmland ecosystems. To validate the effectiveness of this model, a series of ablation studies were conducted involving different modalities data, with/without the Transformer Encoder (TE) modules, and different fusion modules (shallow residual fusion module, deep feature fusion module). Additionally, a comparison was made with early/late stacking fusion models, traditional machine learning models, and deep learning models from relevant studies. The results indicate that the multimodal deep fusion model utilizing HSI, VI, and CHM data achieved a predictive effect of R2 = 0.903 (RMSE = 0.078). Notably, the best performance was observed during the five-leaf stage. The combination of shallow and deep fusion modules demonstrated better predictive performance compared to a single fusion module. The positive impact of the TE module on model performance is evident, as its multi-head attention mechanism aids in better capturing the relationships and importance between feature maps and competition indices, thereby enhancing the model's predictive capability. In weed competition prediction, the multimodal deep fusion model proposed in this study has demonstrated significantly better predictive performance compared to early/late stacking fusion models and other machine learning models (RF, SVR, PLS, DNN-F2 and Multi-channel CNN). Overall, the multimodal deep fusion model developed in this study demonstrates outstanding performance in assessing weed competitiveness and can predict the competitive intensity of weeds in maize across various growth stages on a broad scale.

Shooting Three Birds with One Stone: Device Construction and Thermal Management for Simultaneous Photothermal Conversion Water Evaporation, Thermoelectric Generation and Photocatalytic Degradation

AbstractIt's a promising way to address the global freshwater crisis and energy shortage through solar‐driven devices with evaporate, degrade, and generate electricity at the same time. Low‐efficient light‐thermal conversions for multi‐usage limit application. This paper presents a low‐cost melamine foam/TiO2/carbon black/bismuth (MF/TiO2/CB/Bi) composite with excellent activity to simultaneously process photothermal water evaporation, pollutant degradation, and thermoelectric output, namely‚ shooting three birds with one stone. Under 1 sunlight light intensity, the water evaporation rate reach 4.235 kg m−2 h−1, and the maximum electric power output of a single module is 0.733 W m−2. Meanwhile, Rhodamine B (RhB) solution with 4.0 × 10−4 mol L−1 can be almost degraded within 60 min. Excellent performance benefits from the enhanced adsorption by chemicals, 3D structure for accepting more incident light, and hydrophilic group reducing evaporation enthalpy. Combined with the simulation and experiment, the relationship between heat distribution and thicknesses is studied. When less than 1.98 cm, the lateral temperature is higher than the ambient temperature, thus additional energy cannot be obtained. This work provides a facile and novel method for the construction of photothermal conversion materials with multi‐functional, as a new and useful attempt to solve the shortage of fresh water and electric energy, as well as environmental pollution.

Control of PV power plants with quasi-Z-source cascaded H-bridge multilevel inverters under failure

At the present time, quasi-Z-source cascaded H-bridge multilevel inverters (qZS-CHBMLI) have gained attention in photovoltaic (PV) applications, due to their advantages over traditional multilevel inverters. They allow single-stage power conversion of a PV power plant by independently adjusting the DC voltage in each module; thus, each PV array operates at the maximum power. This advantage permits dispensing with a DC/DC boost converter and reduces the number of modules required. This paper develops a novel control strategy for a qZS-CHBMLI connected to a single-phase system that guarantees proper operation when a fault occurs in a quasi-impedance source inverter (qZSI). The control strategy is employed in a grid-connected qZS-CHBMLI with three modules, each one with a quasi-impedance network, a 4.8 kW PV array and a voltage source inverter (VSI), with H-bridge topology. The purpose of the control system is to deliver a suitable DC voltage at the input of the VSI and ensure the grid power requirements after a fault in a module. The proposed control system is evaluated through a 40 s simulation in MATLAB/Simulink® in two cases: A) analysis of the system behaviour when there is a variation in the operation limit equation; and B) evaluation of the control strategy under dissimilar operating conditions. In addition, an experimental setup based on an OPAL RT-4510 unit and a dSPACE MicroLabBox prototyping unit is employed to validate the results. The results confirmed the correct response of the applied strategy with the failure of a single module.

Color liquid crystal grating based color holographic 3D display system with large viewing angle

Holographic 3D display is highly desirable for numerous applications ranging from medical treatments to military affairs. However, it is challenging to simultaneously achieve large viewing angle and high-fidelity color reconstruction due to the intractable constraints of existing technology. Here, we conceptually propose and experimentally demonstrate a simple and feasible pathway of using a well-designed color liquid crystal grating to overcome the inevitable chromatic aberration and enlarge the holographic viewing angle, thus enabling large-viewing-angle and color holographic 3D display. The use of color liquid crystal grating allows performing secondary diffraction modulation on red, green and blue reproduced images simultaneously and extending the viewing angle in the holographic 3D display system. In principle, a chromatic aberration-free hologram generation mechanism in combination with the color liquid crystal grating is proposed to pave the way for on such a superior holographic 3D display. The proposed system shows a color viewing angle of ~50.12°, which is about 7 times that of the traditional system with a single spatial light modulator. This work presents a paradigm for achieving desirable holographic 3D display, and is expected to provide a new way for the wide application of holographic display.

Automatic detection of small bowel lesions with different bleeding risks based on deep learning models.

Deep learning provides an efficient automatic image recognition method for small bowel (SB) capsule endoscopy (CE) that can assist physicians in diagnosis. However, the existing deep learning models present some unresolved challenges. To propose a novel and effective classification and detection model to automatically identify various SB lesions and their bleeding risks, and label the lesions accurately so as to enhance the diagnostic efficiency of physicians and the ability to identify high-risk bleeding groups. The proposed model represents a two-stage method that combined image classification with object detection. First, we utilized the improved ResNet-50 classification model to classify endoscopic images into SB lesion images, normal SB mucosa images, and invalid images. Then, the improved YOLO-V5 detection model was utilized to detect the type of lesion and its risk of bleeding, and the location of the lesion was marked. We constructed training and testing sets and compared model-assisted reading with physician reading. The accuracy of the model constructed in this study reached 98.96%, which was higher than the accuracy of other systems using only a single module. The sensitivity, specificity, and accuracy of the model-assisted reading detection of all images were 99.17%, 99.92%, and 99.86%, which were significantly higher than those of the endoscopists' diagnoses. The image processing time of the model was 48 ms/image, and the image processing time of the physicians was 0.40 ± 0.24 s/image (P < 0.001). The deep learning model of image classification combined with object detection exhibits a satisfactory diagnostic effect on a variety of SB lesions and their bleeding risks in CE images, which enhances the diagnostic efficiency of physicians and improves the ability of physicians to identify high-risk bleeding groups.

Elastostatic analysis of a module-based shape morphing snake-like robot

This paper describes the stiffness analysis of a module-based shape morphing snake-like robot. Snake-like robots have the characteristic of adapting to unstructured environments by exploiting their ability to reconfigure their body’s shape. However, the excellent mobility contrasts with the ability to transmit high loads, precluding its application in manufacturing operations. This article presents a hybrid structure based on reconfigurable modules equipped with lockable joints. The use of multiple modules in series allows for a large workspace. Furthermore, the parallel structure of the single modules provides for transferring or sustaining high loads. First, the reliability and precision of the theoretical model has been verified using finite element analysis (FEA). The relative errors are less than 5%. Then, a morphing module has been constructed as a physical demonstrator for the kinematic parameters and stiffness parameters used in elastostatic analysis. Finally, a five-segment prototype has been manufactured and tested. There is a deviation between the experimental results and the theoretical results due to manufacturing errors of the prototype but the trend of displacement change shown in the experimental results is basically consistent with the theoretical results.