Search Results (280)

This paper introduces a dual-band planar microwave sensor system for measuring the complex dielectric constant of solid material. The sensor system comprises three constituent parts: the sensing probe, the circuit module and the broadband coupler. The sensing probe is composed of a host part and a sensing area. The host part is composed of a microstrip line, which facilitates system integration with other planar microwave components. The sensing area comprises two pairs of E-interdigital structures, which were originally developed from the interdigital capacitor. This configuration manifests two resonant frequency points, specifically 3 GHz and 3.92 GHz. Consequently, any environmental effects exhibit equivalent variation at both resonant frequency points, thereby substantiating the efficacy of the proposed sensor system for differential operation, which has the capacity to mitigate the impact of environmental conditions. The circuit module comprises a controller, two detectors and a signal generator, which facilitate the generation and processing of radio frequency signals within the system. The function of the broadband coupler is to differentiate between the incident signal and the reflected signal. The operating principle is predicated on the variation in the resonant frequency and peak attenuation with respect to the complex dielectric constant of the material under test (MUT). In order to validate the effectiveness of the proposed sensor system, a prototype is fabricated and tested. The proposed sensor system is distinguished by its high sensitivity and low cost. The apparatus is capable of performing measurements independently and without the necessity for auxiliary equipment. Full article

In recent years, urban risk incidents have become more common. Enhancing infrastructure resilience is not only crucial for adapting to climate change and addressing natural disasters but also serves as a key cornerstone for sustaining urban sustainable development. The research objects for this study are 17 coastal cities in the Bohai Rim region of China. Based on the Complex Adaptive System (CAS) theory, from the multi-dimensional perspective of urban sustainable development, a resilience evaluation index system covering five subsystems, namely transportation, water supply and drainage, energy, environment, and communication, is constructed. Employing panel data from 2013 to 2022, this study develops the entropy weight–TOPSIS model to quantify resilience levels, and applies the obstacle degree model, geographical detector, and Geographically and Temporally Weighted Regression (GTWR) model to analyze influencing factors. The main research results are as follows: (1) The regional infrastructure resilience shows a slow upward trend, but the insufficient synergy among subsystems restricts urban sustainable development; (2) The primary barrier is the drainage and water supply system, and the environmental and communication systems’ notable spatial heterogeneity will result in uneven regional sustainable development; (3) The influence of driving factors such as economic level gradually weakens over time. Based on the above research results, the following paths for resilience improvement and urban sustainable development are proposed: Improve the regional coordination and long-term governance mechanism; Focus on key shortcomings and implement a resilience enhancement plan for water supply and drainage systems; Implement dynamic and precise policy adjustments to stimulate multiple drivers; Enhance smart empowerment and build a digital twin-based collaborative management platform. Full article

Interference caused by multiple reflections is a critical issue in transmission measurements using continuous wave (CW) terahertz and sub-terahertz radiation. This study proposes a practical method to reduce interference effects and improve the stability of transmittance measurements. By deriving analytical expressions for interference patterns under both normal and oblique incidence conditions, we demonstrate that oblique incidence simplifies the interference behavior and allows the reliable extraction of transmittance values from maximum and minimum signal intensities. Using a 95 GHz CW oscillator (Model SFD-753114-103-10SF-P1, Eravant, Torrance, CA, USA) and a 1 mm-thick PET sample, we conducted transmission measurements while varying the detector position. The derived method enabled the calculation of interference-free transmittance values that were consistent across different sample positions. This approach offers a practical technique for material characterization, especially in applications such as nondestructive testing and plastic recycling. Full article

We describe and model a non-cryogenic optical detector designed to count incident photons with metrological accuracy. Our design consists of a semiconductor device operating at $-10$ °C and is predicted to resolve pulses of up to 10 photons with an error rate of 2% in the input number of photons. We present an estimate of the overall device performance using a combination of estimates and simulations of optical loss, discrete electron loss and noise, and electronic noise. Full article

This article proposes a novel three-dimensional trench electrode detector, named the through-type three-dimensional quasi-hemispherical electrode detector. The detector adopts a trench structure to package each independent unit and achieves complete penetration of trench electrodes with the help of an SOI substrate. The horizontal distances from the center anode of the detector to the trench cathode and the detector thickness are equal. It has a near-spherical structure and exhibits spherical-like electrical performance. In this study, we modeled the device physics of the new structure and conducted a systematic three-dimensional simulation of its electrical characteristics, including the electric field, electric potential, electron concentration distribution of the detector, the inducted current caused by incident ions, and the crosstalk between detector units. Computational and technology computer-aided design (TCAD) simulation results show that the detector has an ultra-small capacitance (2.7 fF), low depletion voltage (1.4 V), and uniform electric field distribution. The trench electrodes electrically isolate the pixel units from each other so that the coherence effect between the units is small and can be applied in high-resolution X-ray photon counting detectors to enhance the contrast-to-noise ratio of low-dose imaging and the detection rate of tiny structures, among other things. Full article

The capability to discriminate among nuclear fuel properties is essential for a successful nuclear safeguard and security program. Accurate nuclear material identification is hindered due to challenges such as differing levels of enrichments, weak radiation signals in the case of fresh nuclear fuel, and complex self-shielding effects. This study explores the application of supervised machine learning algorithms to digitized radiation detector data for classifying signatures of special nuclear materials. Three scintillation detectors, an EJ-309 liquid scintillator, a CLYC crystal scintillator, and an EJ-276 plastic scintillator, were used to measure gamma-ray and neutron data from special nuclear material at the National Criticality Experiments Research Center (NCERC) at the National Nuclear Security Site (NNSS), at Nevada, USA. Radiation detector pulse data was extracted from the collected digitized data and applied to three separate supervised learning models: Random Forest, XGBoost, and a feedforward Deep Neural Network, chosen for their wide-spread use and distinct data ingest and processing analytics. Through model refinement, such as adding an additional parameter feature, an accuracy of greater than 95% was achieved. Analysis on model parameter feature importance revealed Countrate, which is the overall gamma-ray and neutron incidents for each detector, was the most influential parameter and essential to include for improved classification. Initial model versions not including the Countrate parameter feature failed to classify. Supervised learning models allow for measured gamma-ray and neutron pulse data to be used to develop effective identification and discrimination between material compositions of different fuel assemblies. The study demonstrated that traditional pulse shape parameters alone were insufficient for discriminating between special nuclear materials; the addition of Countrate markedly improved model accuracy but all models were heavily dependent on this specific feature, thus illustrating the need for alternative, more distinct parameter features. The machine learning development framework captured in this study will be beneficial for future applications in discriminating between different fuel enrichments and additives such as burnable poisons. Full article

Three-dimensional trench electrode silicon detectors play an important role in particle physics research, nuclear radiation detection, and other fields. A novel polysilicon-fill-strengthened etch-through 3D trench electrode detector is proposed to address the shortcomings of traditional 3D trench electrode silicon detectors; for example, the distribution of non-uniform electric fields, asymmetric electric potential, and dead zone. The physical properties of the detector have been extensively and systematically studied. This study simulated the electric field, potential, electron concentration distribution, complete depletion voltage, leakage current, capacitance, transient current induced by incident particles, and weighting field distribution of the detector. It also systematically studied and analyzed the electrical characteristics of the detector. Compared to traditional 3D trench electrode silicon detectors, this new detector adopts a manufacturing process of double-side etching technology and double-side filling technology, which results in a more sensitive detector volume and higher electric field uniformity. In addition, the size of the detector unit is 120 µm × 120 µm × 340 µm; the structure has a small fully depleted voltage, reaching a fully depleted state at around 1.4 V, with a saturation leakage current of approximately $4.8\times {10}^{-10}\mathrm{A}$, and a geometric capacitance of about 99 fF. Full article

The movement towards low-emission and sustainable building practices has driven increased use of natural, carbon-based materials such as wood. While these materials offer significant environmental advantages, their inherent flammability introduces new challenges for timber building safety. Despite advancements in fire protection standards and building regulations, the risk of fire incidents—whether from technical failure, human error, or intentional acts—remains. The rapid detection of fire onset is crucial for safeguarding human life, animal welfare, and valuable assets. This study investigates the potential of monitoring fire precursor gases emitted inside building structures during pre-ignition and early combustion stages. The research also examines the sensitivity and effectiveness of commercial smoke detectors compared with custom sensor arrays in detecting these emissions. A representative structural sample was constructed and subjected to a controlled fire scenario in a laboratory setting, providing insights into the integration of gas sensing technologies for enhanced fire resilience in sustainable building systems. Full article

Background/Objectives: In digital radiography imaging, dual-layer flat-panel detectors (DFDs), in which two flat-panel detector layers are stacked with a minimal distance between the layers and appropriate alignment, are commonly used in material decompositions as dual-energy applications with a single x-ray exposure. DFDs also enable more efficient use of incident photons, resulting in x-ray images with improved noise power spectrum (NPS) and detection quantum efficiency (DQE) performances as single-energy applications. Purpose: Although the development of DFD systems for material decomposition applications is actively underway, there is a lack of research on whether single-energy applications of DFD can achieve better performance than the single-layer case. In this paper, we experimentally observe the DFD performance in terms of the modulation transfer function (MTF), NPS, and DQE with discussions. Methods: Using prototypes of DFD, we experimentally measure the MTF, NPS, and DQE of the convex combination of the images acquired from the upper and lower detector layers of DFD. To optimize DFD performance, a two-step image registration is performed, where subpixel registration based on the maximum amplitude response to the transform based on the Fourier shift theorem and an affine transformation using cubic interpolation are adopted. The DFD performance is analyzed and discussed through extensive experiments for various scintillator thicknesses, x-ray beam conditions, and incident doses. Results: Under the RQA 9 beam conditions of 2.7 μGy dose, the DFD with the upper and lower scintillator thicknesses of 0.5 mm could achieve a zero-frequency DQE of 75%, compared to 56% when using a single-layer detector. This implies that the DFD using 75 % of the incident dose of a single-layer detector can provide the same signal-to-noise ratio as a single-layer detector. Conclusions: In single-energy radiography imaging, DFD can provide better NPS and DQE performances than the case of the single-layer detector, especially at relatively high x-ray energies, which enables low-dose imaging. Full article

Background/Objectives: Ibrutinib is a selective Bruton’s tyrosine kinase inhibitor approved for the treatment of chronic lymphocytic leukemia (CLL). This drug exhibits significant variability in response and toxicity profile, possibly due to genetic polymorphisms in drug-metabolizing enzymes and transporters. The aim of this observational study is to address interindividual variability in the efficacy and safety of ibrutinib treatment in 49 CLL patients. Methods: Genotyping of nine polymorphisms was performed by quantitative polymerase chain reaction (qPCR) using a ViiA7^® PCR Instrument and TaqMan assays, and ibrutinib plasma concentrations were determined using high-performance liquid chromatography coupled to a tandem mass spectrometry detector (HPLC-MS/MS). Results: Our study confirmed a high response rate, with 62% of patients achieving complete remission (CR), 9% CR with incomplete hematologic recovery (CRi), and 24% partial remission (PR). The impact of genetic polymorphisms on the CR rate was evaluated, revealing no statistically significant associations for CYP3A4, CYP3A5, ABCB1, ABCG2, and SLCO1B1 variants. However, a tendency was observed for patients carrying ABCB1 rs1128503, rs1045642 T/T, or rs2032582 A/A genotypes to achieve a higher CR rate. Adverse drug reactions (ADRs) were frequent, with vascular disorders (39%) and infections (27%) being the most common. Genetic polymorphisms influenced ibrutinib toxicity, with CYP3A4 *1/*22 appearing to be protective against overall ADRs. Conclusions: The unexpected association between CYP3A4 *1/*22 genotype and lower ADR incidence, as well as the trend toward improved treatment response in patients carrying ABCB1 genotypes, suggests compensatory metabolic mechanisms. However, given the small sample size, larger studies are needed to confirm these findings and their clinical implications, while also aiming to uncover other non-genetic factors that may contribute to a better understanding of the variability in treatment response and toxicity. Full article

This study evaluated the prevalence of aflatoxin M1 (AFM1) in milk marketed in Tirana, Albania, along with dietary exposure and associated potential health risks. The World Health Organization has categorized Albania in cluster G02 of GEMS/FOOD, highlighting that milk is a staple in the Albanian diet, which points to a possible health risk. A total of 141 milk samples, comprising both Ultra-High Temperature (UHT) and pasteurized types, were collected from local markets in Tirana and analyzed from March 2023 to February 2024. The determination of AFM1 levels was carried out using High-Pressure Liquid Chromatography with a Fluorescence Detector (HPLC-FLD), a precise and dependable technique for identifying and measuring aflatoxins in food products. Aflatoxin M1 was found in 62.4% of the milk samples, with 26.2% surpassing the European Union’s maximum residue levels (MRL). The mean AFM1 concentrations were 58.8 ± 95.8 ng/kg, reaching a maximum level of 399.0 ng/kg. The Estimated Daily Intake (EDI) for various groups—toddlers, children, adolescents, and adults—was determined to be 2.161, 1.297, 0.519, and 0.370 ng/kg of body weight per day, respectively. The Hazard Index (HI), derived from the AFM1 exposure for four population groups, was 10.81 (toddlers), 6.48 (children), 2.59 (adolescents), and 1.85 (adults). The Margin of Exposure (MoE) was 1.85, 3.08, 7.71, and 10.81, respectively. The incidence of hepatocellular carcinoma (HCC) per 100,000 people in the four groups was 0.034, 0.021, 0.008, and 0.006, respectively. The study is the first comprehensive evaluation of AFM1 prevalence, highlighting the potential risks associated with milk consumption, as milk is a dietary staple in Albanian households. It addresses a critical public health concern regarding aflatoxin M1 (AFM1) contamination in milk consumed in Tirana, Albania, by highlighting the need for ongoing monitoring, regulatory measures, and educational outreach to enhance food safety and safeguard public health in Albania, as well as in other regions facing similar concerns. Full article

This study developed a neutron-beam-focusing supermirror for grazing-incidence small-angle neutron scattering (GISANS) measurements. We adopted point-to-point beam focusing based on an ellipse whose two foci correspond to a virtual point source and a spot on the detector surface. The focusing supermirror was fabricated by depositing NiC/Ti supermirror film with ion-beam sputtering on a precise elliptic surface of fused quartz figured using the elastic emission machining technique. Neutron measurements at the pulsed neutron reflectometer BL17 of the MLF, J-PARC, successfully demonstrated that the focusing supermirror enhances the beam intensity twentyfold compared with an optimally collimated beam, achieving a signal-to-background ratio of the focal spot as high as 500. The mirror can be readily installed and used at BL17 for time-of-flight GISANS measurements. Full article

In this paper, a method of estimating the probability of susceptibility of a component on a circuit board to electromagnetic interference (EMI) is presented. The integrated circuit electromagnetic compatibility (IC EMC) standard IEC 62132-4 enables the assessment of the susceptibility of an IC by determining the forward power incident on each pin required to induce a malfunction. Although we focus on IC susceptibility, the method might be applied to other components and sub-circuits where the same information is known. Building upon a previously established numerical model capable of estimating the average coupled forward power at the end of a trace of a lossless PCB trace for a known load in a reverberant environment, this paper updates the model by incorporating PCB losses and utilizes the updated model to estimate the distribution of coupled forward power at the package pin over a number of boundary conditions in a reverberant field. Thus, the probability of failure can be predicted from the known component susceptibility level, the length, transmission line parameters, and the loading of the track to which it is attached. To validate this numerical model, the paper includes measurements obtained with a custom-designed RF IC detector, created for the purpose of measuring RF power coupled into the package pin via test PCB tracks. Full article

Recent advances in machine learning have opened new avenues for optimizing detector designs in high-energy physics, where the complex interplay of geometry, materials, and physics processes has traditionally posed a significant challenge. In this work, we introduce the end-to-end. AI Detector Optimization framework (AIDO), which leverages a diffusion model as a surrogate for the full simulation and reconstruction chain, enabling gradient-based design exploration in both continuous and discrete parameter spaces. Although this framework is applicable to a broad range of detectors, we illustrate its power using the specific example of a sampling calorimeter, focusing on charged pions and photons as representative incident particles. Our results demonstrate that the diffusion model effectively captures critical performance metrics for calorimeter design, guiding the automatic search for a layer arrangement and material composition that align with known calorimeter principles. The success of this proof-of-concept study provides a foundation for the future applications of end-to-end optimization to more complex detector systems, offering a promising path toward systematically exploring the vast design space in next-generation experiments. Full article

To push the boundaries of confocal microscopy beyond its current limitations by predicting sensor responses for complex surface geometries, we build digital twins using three rigorous models, the finite element method (FEM), Fourier modal method (FMM), and boundary element method (BEM) to model light–surface interactions. Fourier optics are then used to calculate the sensor signals at the back focal plane and at the detector. A 3D illumination model is applied to 2D periodic structures for FEM and FMM modelings and to 3D aperiodic structures for BEM modeling. The lateral and vertical scanning processes of the confocal microscope are achieved through focal-point shifts of the objective, using plane-wave illuminations with varying incident and azimuthal angles. This approach reduces the need for repeated, time-intensive rigorous simulations of the scattering process when a fine scanning is desired. Furthermore, we give an in-depth description of a novel confocal microscopy method using FMM. For rectangular grating surfaces, the three models yield identical, highly accurate results, as validated by measured results. Simulations of the instrument transfer function, tilted gratings, and gratings with edge rounding offer insights into some experimentally observed effects. This research therefore provides a promising approach for correcting systematic errors in confocal microscopy. Full article