The hardware Trojan (HT) has become a major threat for the integrated circuit (IC) industry and supply chain, and has motivated numerous developments of Trojan detection schemes. Although the ...side-channel method is the most promising one, nearly all of the side-channel methods require fabricated golden chips, which are very difficult to obtain in reality. In this paper, we propose a novel strategy for HT detection using electromagnetic side-channel-based spectrum modeling and analyzing. We utilize the design data at early stage of the IC lifecycle, and the generated spectrum can serve as the golden reference, and thus we do not need the fabricated golden chips anymore. Another very important feature is that our method is immune to the process variation theoretically. Experimental results on selected Advanced Encryption Standard benchmark circuits on FPGA show that our proposed method can effectively detect Trojans even with very small traces.
The present study examined the relationship between thyroid function status and the prevalence of metabolic syndrome in a Chinese population.
Cross-sectional data were obtained from the Thyroid ...Disease, Iodine Nutrition and Diabetes Epidemiology (TIDE) Survey. A total of 62,408 subjects aged ≥18 years were enrolled. Differences in metabolic indicators and the prevalence of metabolic syndrome according to sex and thyroid function status were compared. Logistic regression was used to analyze the influence of thyroid function on metabolic syndrome and its components.
The prevalence of metabolic syndrome was generally higher in men than women. Overt hyperthyroidism and subclinical hypothyroidism had a significant effect on metabolism in men. Body mass index (BMI), waist circumference, and triglycerides (TGs) were significantly lower in men in the overt hyperthyroidism group, and BMI, waist circumference, systolic blood pressure (SBP) and TGs were higher in men in the subclinical hypothyroidism group than men in the normal group. Overt and subclinical hypothyroidism had significant impacts on metabolic components in women. BMI, waist circumference, TGs, SBP and DBP in the subclinical and overt hypothyroidism groups were significantly higher than the euthyroid group in women. The relative risk of abdominal obesity and hypertriglyceridemia was increased in women with hypothyroidism. Thyroid dysfunction had different effects on metabolic syndrome and its components before and after menopause.
Thyroid function had important effects on the prevalence of metabolic syndrome. Women with hypothyroidism, especially post-menopausal women, had a higher risk of metabolic syndrome than men.
Multi-channel airborne full-waveform LiDAR is widely used for high-precision underwater depth measurement. However, the signal quality of full-waveform data is unstable due to the influence of ...background light, dark current noise, and the complex transmission process. Therefore, we propose a nonlocal encoder block (NLEB) based on spatial dilated convolution to optimize the feature extraction of adjacent frames. On this basis, a coupled denoising encoder–decoder network is proposed that takes advantage of the echo correlation in deep-water and shallow-water channels. Firstly, full waveforms from different channels are stacked together to form a two-dimensional tensor and input into the proposed network. Then, NLEB is used to extract local and nonlocal features from the 2D tensor. After fusing the features of the two channels, the reconstructed denoised data can be obtained by upsampling with a fully connected layer and deconvolution layer. Based on the measured data set, we constructed a noise–noisier data set, on which several denoising algorithms were compared. The results show that the proposed method improves the stability of denoising by using the inter-channel and multi-frame data correlation.
Background
Headache during hemodialysis (HDH) is prevalent but not negligible. Despite the high prevalence of dialysis headaches, they have rarely been studied. Therefore, this study aimed to ...evaluate the prevalence, risk factors, and clinical characteristics of HDH and reappraise the HDH diagnostic criteria in the International Classification of Headache Disorders 3 (ICHD-3).
Methods
One hundred and fifty-four patients completed this randomized cross-sectional study. Consecutive patients who underwent haemodialysis were assessed using a semi-structured questionnaire. The patients were administered face-to-face questionnaires while undergoing dialysis.
Results
This study included 154 patients. Before commencing dialysis, 3.24% (5/154) of the patients had migraine without aura, 1.29% (2/154) had menstrual-related migraine, 0.6% (1/154) had tension-type headaches, and 0.6% (1/154) had an unclassifiable headache. One case (0.6%) of headache resolved after dialysis treatment. HDH was diagnosed in 9.09% (14/154) of the patients. Headache after haemodialysis (HAH) was reported in 6.49% (10/154) of patients. The most prevalent features of HDH were frontal or temporal location, bilateral headaches, dull and throbbing nature, and moderate severity. HDH started at a mean of 2.33 ± 0.79 h after dialysis commenced. The average headache duration was 6.56 ± 1.57 h (median = 3.0 h), with 66.67% of the patients reporting a duration of ≤4 h. HDH was more prevalent in females than males (
P
= 0.01,
P
< 0.05). Female sex was a risk factor for HDH (
P
= 0.01，
P
< 0.05).
Conclusions
The diagnostic criteria for 10.2 HDH in ICHD-3 may miss several HAH. Therefore, ICHD-3 should be revised according to the literature and further studies.
Acoustic sensors and acoustic measurements receive much attention in various applications. Because waveguides are commonly used in sensor design, theoretical means to study acoustic propagation and ...interaction in waveguides are necessary. However, current methods for elastic wave coupling, including the transfer matrix method and coupled mode theory in planar 2D waveguides, are not satisfactory. In this work, a coupled mode analysis for acoustic waves in 3D stress-free elastic waveguides is proposed. Similar to the coupled mode theory in optical waveguides, the analysis is presented by the evolution of modal amplitudes. It can solve various modal conversion and scattering problems in elastic waveguides with small changes of cross sections and stress-free boundaries. To demonstrate the practicability, the coupled mode analysis is used to calculate the reflection spectrum of the newly proposed structure, the acoustic fiber Bragg grating. In a notch-based grating fabricated on a thin cylindrical waveguide, the results from coupled mode analysis are in good agreement with those from the transfer matrix method, which has been already validated experimentally. The coupled mode analysis is a promising method to solve various scattering problems.
A novel concept of acoustic fiber Bragg grating (AFBG) was conceived and experimentally validated as an effective technique for high-temperature sensing. Similar to the well-known optical fiber Bragg ...grating, the AFBG employs interactions between waves and periodic structures on an elongated waveguide. Acoustic waves reflected from periodic structures interfere with each other and result in the emergence of resonance frequency when acoustic wavelength matches with pitch length of the periodic structures. When the single-mode operation condition is satisfied, the resonance frequency location can be accurately resolved and thus be used as an effective indicator for temperature sensing. To demonstrate this concept, an AFBG sample was fabricated on a telecommunication optical fiber (125-μm diameter) with femtosecond laser micromachining setup, and it demonstrated sensing capability up to 700 °C, which was limited by the fiber material (fused silica) and could be over 1400 °C if other material, such as sapphire, was used as the waveguide. With the features of various applicable material, low system cost, and potential multiplexing capability, this AFBG technology is a promising candidate for high-temperature sensing, even in a distributed manner.
This cross-sectional survey aimed to investigate the prevalence of depression among medical staff and its risk factors as well as the association between depression, anxiety, headache, and sleep ...disorders.
Stratified random cluster sampling was used to select medical staff from various departments of four hospitals in Sanya City. The Self-Rating Depression Scale (SDS), Self-Rating Anxiety Scale (SAS), and Pittsburgh Sleep Quality Index (PSQI) were used to quantitatively assess depression, anxiety, and sleep disorders. Correlation and regression analyses were performed to determine factors affecting the depression occurrence and scores.
Among 645 medical staff members, 548 (85%) responded. The 1-year prevalence of depression was 42.7% and the prevalence of depression combined with anxiety, headache, and sleep disorders was 23, 27, and 34.5%, respectively. The prevalence of depression in women, nurses, the unmarried or single group, and the rotating-shift population was significantly higher than that in men (48.3% vs. 27.1%, odds ratio OR = 2.512), doctors (55.2% vs. 26.7%, OR = 3.388), the married group (50.5% vs. 35.8%, OR = 1.900), and the day-shift population (35.2% vs. 7.5%, OR = 1.719). The occurrence of depression was correlated with anxiety, sleep disorders, headache, and migraines, with anxiety having the highest correlation (Spearman's Rho = 0.531). The SDS was significantly correlated with the SAS and PSQI (Spearman's Rho = 0.801, 0.503) and was also related to the presence of headache and migraine (Spearman Rho = 0.228, 0.159). Multiple logistic regression indicated that nurse occupation and anxiety were risk factors for depression, while grades of anxiety, sleep disorders and nurse occupation were risk factors for the degree of depression in multiple linear regression.
The prevalence of depression among medical staff was higher than that in the general population, especially among women, nurses, unmarried people, and rotating-shift workers. Depression is associated with anxiety, sleep disorders, headache, and migraines. Anxiety and nursing occupation are risk factors for depression. This study provides a reference for the promotion of occupational health among medical professionals.
•The bubble growth characteristics of pure and mixed refrigerants were studied.•An experimental test was conducted to observe the single bubble growth processes.•The mass diffusion effect of bubble ...growth was underestimated in literatures.•A correlation for the effective superheat was developed.
The reduction of the bubble growth rate in mixed liquid refrigerants is one of the main reasons for the reduction of the boiling heat transfer coefficient. To study the mass diffusion effect and the reduction of the bubble growth rate in boiling of non-azeotropic mixtures, an experiment was conducted to investigate the bubble growth rates of R142b, R134a, isobutane and R142b/R134a mixtures in a vertical transparent quartz tube. The pressure used in this experiment ranged from 0.2 to 0.47 MPa, and the superheats ranged from 1.5 to 23.3 °C. Moreover, in order to obtain a uniformly superheated liquid, the bubbles were grown at a single nucleation site, and the departure frequency for the successive bubbles was lower than 20 Hz. Experimental bubble growth constants were obtained, and the reliability of the experimental study was supported by theoretical models for pure refrigerants. Additionally, for the study of bubble growth rate in binary mixtures, the attenuation factors for superheat were calculated and compared with different proposed models. The experimental attenuation factors were much smaller than the calculated results. Thus, a correlation was identified, and the errors were primarily in the range of −30% to +30%.
•The concentration fluctuation effect was proposed to account for the reduction of boiling site density.•A model adopting the fluctuation theory was developed to calculate the concentration ...fluctuation effect.•Experimental tests were conducted to investigate the boiling site density of pure and mixed refrigerants.•Based on the present data, a correlation is proposed to predict the boiling site density for pure refrigerants.•Attenuation factors were calculated for the boiling site densities of binary mixtures.
The reduction of the boiling nucleation site density in mixed liquid refrigerants is one of the main reasons for the reduction of the boiling heat transfer coefficient. Instead of the mass diffusion effect, this work proposes the concentration fluctuation effect to account for the reduction in the boiling site density. Evidence is provided to support this hypothesis, and a model adopting the fluctuation theory is developed. In addition, experimental tests were conducted to investigate the boiling site densities of i-butane, propane, R134a/R32 and i-butane/propane under pressures in the range of 0.25–1MPa and wall superheats in the range of 3–25°C. For the pure refrigerants, the boiling nucleation site density showed a linear relation with wall superheat. Additionally, a correlation is proposed to predict the boiling site density based on the present data. In the case of binary mixtures, the boiling site density first decreased and then increased as the concentration of the high boiling point fraction was increased. The experimental attenuation factors of boiling site densities were calculated for binary mixtures. Qualitative calculations from the proposed model showed good agreement with the experimental data.
Side-channel attack (SCA) is one of the physical attacks, which will reveal the confidential information from cryptographic circuits by statistically analyzing physical manifestations. Various ...circuit-level countermeasures have been proposed as fundamental solutions to eliminate the correlations between side-channel information and circuit's internal operations. The existing solutions, however, will introduce nonnegligible power and area overheads, making them difficult to be deployed in resource-constrained applications. In this article, a novel three-independent-gate silicon nanowire field effect transistor (TIGFET) with the intrinsic SCA-resilience characteristics is introduced to balance the tradeoffs among cost, performance, and security of cryptographic implementations. We construct six TIGFET-based current mode logic (CML) gates that can retain lower power variation under all possible transitions compared to the CMOS counterparts. As a proof of concept, advanced encryption standard (AES), SM4 block cipher algorithm (SM4), and lightweight cryptographic algorithm PRESENT are implemented utilizing the TIGFET-based CML gates. Correlation power attack is performed to evaluate the improvement of SCA resilience. Simulation results verify that the TIGFET-based cryptographic implementations decrease 42.37% area usage, lower 61.16% energy efficiency, reduce <inline-formula> <tex-math notation="LaTeX">5.35\times </tex-math></inline-formula> power variation, and achieve a similar level of SCA resistance compared to the CMOS counterpart, which is applicable for the resource-constrained applications.
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