Sensitivity Coefficients Research Articles

The influence of temperature and pressure on the self-diffusion characteristics and mechanical sensitivity of DNTF: a molecular dynamics study.

3,4-Bis(3-nitrofurazan-4-yl) furoxan (DNTF) is a typical low-melting-point, high-energy-density compound that can serve as a cast carrier explosive. Therefore, understanding the safety of DNTF under different casting processes is of great significance for its efficient application. This study employed molecular dynamics simulations to investigate the effects of temperature and pressure on the self-diffusion characteristics and mechanical sensitivity of DNTF. The analysis focused on the mean square displacement, self-diffusion coefficient, cohesive energy density, non-bonded energy, and critical bond length of DNTF under various temperatures (250 to 450K) and pressures (0.1 to 10MPa). The results indicate that the self-diffusion coefficient and mechanical sensitivity of DNTF are more sensitive to changes in temperature. As the temperature increases, the self-diffusion behavior of DNTF accelerates, making it more volatile. This effect is particularly notable within the temperature range of 350 to 400K, where the growth rate of the self-diffusion coefficient is significantly faster than in the 250 to 350K range. The trigger bond length (Lmax) gradually increases with rising temperature, accurately reflecting the objective trend that mechanical sensitivity increases with temperature. The results of this study provide a theoretical basis for the application of DNTF in high-energy materials, particularly in enhancing its safety. An 8 × 4 × 2 supercell model comprising 256 DNTF molecules was constructed in the Materials Studio 8.0 package. The DNTF supercell was geometrically relaxed using the conjugate gradient method. Subsequently, a 10-ps NPT molecular dynamics simulation was conducted on the supercell under conditions of 300K and 0.1MPa to relieve internal stresses, thereby obtaining DNTF crystals in the equilibrium state. NPT molecular dynamics simulations of the DNTF supercell were then carried out under the COMPASS force field at constant temperature. The temperatures were set to 250K, 300K, 350K, 400K, and 450K, and the pressures were set to 0.1MPa, 1MPa, 3MPa, 5MPa, and 10MPa. The total simulation time was 1000ps with a time step of 1fs. Every 1000 steps, information on mean square displacement, non-bonded energy, intermolecular forces, and critical bond length was recorded.

Reusable Turbine Material GH4586: Stochastic Analysis and Reliability Assessment of Low‐Cycle Fatigue Life Parameters at Multiple Temperatures

ABSTRACTTurbines, crucial in reusable rocket engines, benefit significantly from precise fatigue life forecasting in their force‐thermal cyclic loading conditions. Further, low‐cycle fatigue life predictions can be random due to uncertainties in material properties. This study aims to analyze the probabilistic low‐cycle fatigue life of GH4586 under different temperature. Mechanical and thermal tests were carried out for the temperatures between 87 K and 1173 K. Random distributions of low‐cycle fatigue parameters were obtained using various methods. The cyclic life reliability of a reusable rocket engine turbine rotor blisk was analyzed using stochastic low‐cycle fatigue parameters. Mitchell's method had a higher prediction accuracy when the reliability was greater than 0.8. Sensitivity analysis shows the significant impact of GH4586 fatigue parameters on cyclic life reliability. Sensitivity coefficients of strength coefficient and ductility coefficient are 32.73% and 27.06%, respectively. These findings provide valuable insights that inform the design of turbines and enhance their reliability.

An Evolutionary Game Model of a Regional Logistics Service Supply Chain Complex Network in a Blockchain Environment

Blockchain technology offers a novel solution to address the issue of information silos present in the complex network system of regional logistics service supply chains. Furthermore, enhancing the willingness of participants to engage in this system has emerged as a critical issue requiring urgent resolution. This study assumes bounded rationality and constructs an evolutionary game model to analyze the adoption behaviors of logistics service providers (LSPs) and logistics service integrators (LSIs) in a blockchain environment. The stability theorem of differential equations is employed to elucidate the inherent decision-making mechanisms present in the game. Acknowledging that traditional evolutionary mechanisms often neglect individual heterogeneity and the dynamic changes in the topological structures of complex networks, this study further involves the development of an evolutionary game model tailored for the complex network of a regional logistics service supply chain. After validating the effectiveness of the model, this research investigates how market environmental factors influence the adoption behaviors of LSPs and LSIs. Finally, through case simulations, the effects of key influencing factors on participatory behaviors within the regional logistics service supply chain are analyzed. The findings indicate that, in a blockchain environment, both prior to and following the adoption of complex network technology in the regional logistics service supply chain, the equilibrium stability of the network system is jointly determined by the total revenues of LSPs and LSIs. External factors in the blockchain environment significantly influence technology adoption strategies. Notably, when both the sensitivity coefficients of market demand relative to price and logistics service costs concerning quality enhancement are high, the willingness of supply chain participants to adopt the technology declines rapidly. As the quality elasticity increases, the technology adoption rates of providers and integrators initially stabilize and subsequently increase exponentially. Changes in the revenues of logistics service providers have no significant impact on technology adoption rates within the regional logistics service supply chain.

A 291-day Evaluation of the Performance of a Consumer-grade Temporal Radon Detector.

Affordable, accurate, and robust temporal measurement devices are desirable for screening and assessment of radon levels in private homes and workplaces. This research expands upon prior research, using the RadonFTlab RadonEye device through a comparison of multiple samples of this instrument with a laboratory-grade instrument, the Saphymo AlphaGUARD, over a more extensive period than reported previously. Data were collected over 291 d in a poorly ventilated basement space in an occupied building. Environmental conditions varied naturally, changing both the radon source term and radon entry into the space approximating typically deployed conditions. The R-squared linear regression correlation coefficient and relative sensitivities of each RadonEye with the AlphaGUARD were computed. Overall temporal and diurnal variations were also studied. The sensitivities of all RadonEyes and the AlphaGUARD agreed to within 22% throughout the entire deployment period.

Exploring bioconvective heat transfer dynamics on curved surfaces: Insights into non‐Newtonian behavior and multifaceted influencing factors

AbstractThis research article investigates the bioconvective flow of a second‐grade fluid along a curved surface, considering non‐Newtonian behavior and diverse influencing factors such as heat generation, chemical reactions, slip, Lorentz force, and viscous dissipation. By employing MATLAB's bvp4c tool and the similarity transformations, the nondimensional partial differential equations are solved. We discover that the stable and unstable solutions differ significantly from one another, which has significant consequences for industries including microfluidic devices and curved surface manufacturing. The study also examines the effects of homogenous and heterogenous reaction parameters on reactant concentrations, revealing that higher values reduce concentration, particularly for the second solution. Designing effective heat exchangers and chemical reactors requires consideration of the sensitivity of skin friction coefficient and Nusselt number to curvature, slip, and heat generation, as demonstrated by this work. The findings may guide future experimental study and yield important insights for optimization of bioconvective systems.

Agreement between self-reported and objectively measured hypertension diagnosis and control: evidence from a nationally representative sample of community-dwelling middle-aged and older adults in China.

As the population ages, hypertension has become the leading risk factor for cardiovascular diseases (CVDs) and premature deaths worldwide. Accurate monitoring of CVD risks and planning community-based public health interventions require reliable estimates of hypertension prevalence and management. While the validity of self-reporting in assessing hypertension prevalence has been debated, the concordance between self-reports and clinical measurements of hypertension control remains underexplored, particularly in large, community-based older populations. This study aims to examine the agreement between self-reported and objectively measured data on both hypertension diagnosis and control, as well as the associated factors, among community-dwelling middle-aged and older Chinese adults. Data from the China Health and Retirement Longitudinal Study were utilized, with household survey responses combined with biomedical data. Sensitivity, specificity, and kappa coefficients were used to assess the agreement between self-reported and objectively measured hypertension diagnosis in the general sample, and the agreement on hypertension control among individuals who reported having hypertension. Binary and multinomial logistic regression analyses were conducted to identify individual, household, and community-level factors associated with the agreement. Self-reports exhibited substantial sensitivity, excellent specificity, and moderate agreement with objective measurements for hypertension diagnosis, while demonstrating fair sensitivity, excellent specificity, but low agreement for hypertension control. The odds of agreement on hypertension diagnosis were negatively associated with older age and heavy drinking, but positively related to marital status, higher education, chronic kidney disease, recent healthcare service utilization, and higher household economic levels. Meanwhile, the likelihood of agreement on hypertension control was negatively associated with older age, comorbid diabetes or cardiovascular disease, heavy drinking, BMI over 25, and antihypertensive medication adherence, but positively associated with recently healthcare service utilization. Self-reporting underestimated hypertension prevalence but significantly overestimated the hypertension control rates. For middle-aged and older Chinese adults, individual-level factors including age, multimorbidity, behavioural risks, and healthcare-seeking behaviours were identified as significant predictors of agreement between self-reported and objectively measured hypertension data. Recognizing these factors is essential for improving the accuracy of chronic condition estimates and facilitating targeted chronic disease management programs for China's aging population and other developing countries with similar demographic and health challenges.

The Influence of the Surface Density of Thermally Expanded Graphite Sheets on the Acoustic Wave Transmission

The paper presents the results of experimental and theoretical studies of the influence of the surface density of a thin porous sheet of thermally expanded graphite on the transmission coefficient of the acoustic wave. The possibility of using the theory of thin films to describe the processes of transmission of acoustic waves through porous sheet in the field of low frequencies and small thicknesses has been proven. The influence of the operating frequency on the sensitivity of the transmission coefficient to the surface density of the sheet was assessed.

Sensitivity calibration method of FBG strain sensor in high and low temperature conditions

Abstract Strain and temperature sensitivity coefficients of fiber Bragg grating (FBG) sensors are of vital importance to measuring accuracy, especially in varying temperature conditions. To improve the measurement accuracy of the FBG strain sensor, its strain and temperature sensitivity coefficients must be calibrated before use. In this study, we designed a substrate FBG strain sensor using the metal packaging method and illustrated its packaging process. A sensitivity calibration method for FBG strain sensors under different high-low temperatures was proposed. Additionally, an equal-intensity cantilever beam with the same material as the application structures of the FBG strain sensor, which affords loads within the range of −2500 to 3000 μϵ was designed and manufactured. A modified coefficient of strain δ was introduced to modify the strain results according to the calibration principle of an equal-intensity cantilever beam. Furthermore, a FBG unstressed temperature compensation method was proposed to compensate for the temperature of the FBG strain sensor. To verify the performance of the proposed sensitivity calibration method, a series of calibration experiments under −55 °C, −20 °C, 0 °C, 20 °C, 50 °C, and 70 °C were implemented, which proved the excellent performance of the proposed calibration method. Finally, the temperature and strain sensitivity coefficients of the FBG strain sensor in the temperature range of −55 °C to 70 °C are achieved at 0.3022 nm °C−1 and 0.5039 pm μϵ −1. The proposed sensitivity calibration method in high-low temperatures is simple and easy to implement. Meanwhile, the calibrated FBG strain sensor has prospective applications for strain measurement in structural health monitoring of aircraft, especially under varying temperature conditions.

Quantification analysis of high-speed train aerodynamics with geometric uncertainty of streamlined shape

Purpose This study aims to get a better understanding of the impact of streamlined high-speed trains (HSTs) with geometric uncertainty on aerodynamic performance, as well as the identification of the key parameters responsible for this impact. To reveal the critical parameters, this study creates a methodology for evaluating the uncertainty and sensitivity of drag coefficient induced by design parameters of HST streamlined shapes. Design/methodology/approach Bézier curves are used to parameterize the streamlined shape of HSTs, and there are eight design parameters required to fit the streamlined shape, followed by a series of steady Reynolds-averaged Navier–Stokes simulations. Combining the preparation work with the nonintrusive polynomial chaos method results in a workflow for uncertainty quantification and global sensitivity analysis. Based on this framework, this study quantifies the uncertainty of drag, pressure, surface friction coefficient and wake flow characteristics within the defined ranges of streamline shape parameters, as well as the contribution of each design parameter. Findings The results show that the change in drag reaches a maximum deviation of 15.37% from the baseline, and the impact on the tail car is more significant, with a deviation of up to 23.98%. The streamlined shape of the upper surface and the length of the pilot (The device is mounted on the front of a train’s locomotive and primarily serves to remove obstacles from the tracks, thereby preventing potential derailment.) are responsible for the dominant factors of the uncertainty in the drag for HSTs. Linear regression results show a significant quadratic polynomial relationship between the length of the pilot and the drag coefficient. The drag declines as the length of the pilot enlarges. By analyzing the case with the lowest drag, the positive pressure area in the front of pilot is greatly reduced, while the nose tip pressure of the tail is enhanced by altering the vortices in the wake. The counter-rotating vortex pair is significantly attenuated. Accordingly, exerts the impacts caused by geometric uncertainty can be found on the wake flow region, with pressure differences of up to 900 Pa. The parameters associated with the shape of the upper surface contribute significantly to the uncertainty in the core of the wake separation region. Originality/value The findings contribute to a better understanding of the impact of streamlined HSTs with geometric uncertainty on aerodynamic performance, as well as the identification of the key parameters responsible for this impact. Based on this study, future research could delve into the detailed design of critical areas in the streamlined shape of HSTs, as well as the direction of shape optimization to more precisely and efficiently reduce train aerodynamic drag under typical conditions.

Scaled Sensitivity of Pavement–Mechanistic-Empirical Transfer Function Coefficients for Flexible and Rigid Pavements

The American Association of State Highway and Transportation Officials (AASHTO)Ware Pavement–Mechanistic-Empirical (ME) transfer functions need local calibration for reliable performance predictions. It is often not viable to calibrate all coefficients at the same time. Therefore, it is crucial to identify the most sensitive transfer function coefficients. Moreover, the sensitivity also indicates the impact of each coefficient on the performance prediction. Several studies have shown the sensitivity of the Pavement-ME design inputs, but limited research is available on the sensitivity of transfer function coefficients. Typically, the sensitivity is obtained using a normalized sensitivity index (NSI). This paper estimated the sensitivity of the Pavement-ME transfer function coefficients using scaled sensitivity coefficients (SSCs). NSI values are compared with the SSCs. Ten sections, each from flexible and rigid pavements, were used to calculate the NSI values. These are existing pavement sections from the Michigan Department of Transportation (MDOT) pavement management system (PMS) database, designed using the 1993 AASHTO design guide. Results show that SSCs provide a more reliable sensitivity on a range of independent variables rather than a point estimate, unlike NSI. NSI values showed variability among different sections and magnitudes of predicted performance. Calculation of SSCs is a forward problem and does not require any input data. A mathematical model (transfer function) is needed; therefore, SSCs can be calculated on any range of independent variables. It also shows the potential correlation between different coefficients and accuracy in estimation.

Effect of thermal change on acoustoelastic effect in concrete

Acoustoelastic technology, which measures changes in ultrasonic wave velocity to determine structural stress, shows significant potential for assessing stress in concrete structures. However, environmental temperature variations can affect ultrasonic wave velocity, thereby influencing the accuracy of acoustoelastic measurements. This study examines the impact of thermal changes on ultrasonic wave velocity in concrete (thermo-acoustoelastic effect) and compares it with changes caused by stress variations (classical acoustoelastic effect). Theoretical expressions for both thermal and classical acoustoelastic effects in a natural coordinate system are derived, and the sensitivity coefficients for each effect are provided. Equivalent elastic constant method is proposed for preliminary numerical analysis of both effects. Experimental investigations further explore how the thermal changes influence the classical acoustoelastic effect. Results reveal that the velocity change due to a unit temperature variation is approximately 40 % of that caused by a unit stress variation. This underscores the significant impact of temperature fluctuations on the application of classical acoustoelastic technology and highlights the need for an effective temperature compensation mechanism to ensure measurement reliability. This finding is of substantial significance for advancing acoustoelasticity-based stress detection technology in concrete structures.

Validation and reproducibility of the International Study of Asthma and Allergies in Childhood (ISAAC) Written Allergic Rhinitis Questionnaire for phone survey in children aged 6‒7 years

ObjectiveTo validate and assess the reproducibility of the ISAAC Written Allergic Rhinitis Questionnaire (WARQ) for children aged between 6 and 7 years by telephone contact. MethodsObservational study through interviews with guardians of children aged 6–7 years using the ISAAC Allergic Rhinitis (AR) module questionnaire in three different phases separated by 2 weeks each: telephone interviews in the first and third contacts and face-to-face interviews, with the same guardian of telephone interviews, in the second contact. Reproducibility was estimated using the Kappa index and validation using the sensitivity and specificity coefficients. ResultsData from 94 children (48 from the allergic rhinitis Control Group ‒ CG) were analyzed. Reproducibility showed perfect agreement (100%) for the question number 1 – Which refers to the symptoms of AR, ever: “Has your child ever had a problem with sneezing or a runny or a blocked nose when he/she did not have a cold or the flu?” and for the question number 2 – Which refers to current symptoms of AR: “In the past 12 months, has your child had a problem with sneezing or a runny or a blocked nose when he/she did not have a cold or the flu?” A strong agreement was also observed for the question number 3 (κ = 0.871) – it defines the presence of comorbidity of allergic rhinoconjuntivitis “In the past 12 months, has this nose problem been accompanied by itchy-watery eyes?” The validation showed high specificity (≥76.7%) and sensitivity (≥98%) for all questions, except for the ones related to seasonality and intensity of symptoms. ConclusionsOur results showed that the ISAAC AR module questionnaire by telephone interviews has good reproducibility and high agreement with the clinical diagnosis of AR. It may be an appropriate alternative tool in epidemiological studies of childhood AR, especially in periods of social isolation, such as Coronavirus pandemic. Level of evidenceCohort Study. Level IV

Sensitivities in protein allocation models reveal distribution of metabolic capacity and flux control.

Expanding on constraint-based metabolic models, protein allocation models (PAMs) enhance flux predictions by accounting for protein resource allocation in cellular metabolism. Yet, to this date, there are no dedicated methods for analyzing and understanding the growth-limiting factors in simulated phenotypes in PAMs. Here, we introduce a systematic framework for identifying the most sensitive enzyme concentrations (sEnz) in PAMs. The framework exploits the primal and dual formulations of these models to derive sensitivity coefficients based on relations between variables, constraints, and the objective function. This approach enhances our understanding of the growth-limiting factors of metabolic phenotypes under specific environmental or genetic conditions. Compared to other traditional methods for calculating sensitivities, sEnz requires substantially less computation time and facilitates more intuitive comparison and analysis of sensitivities. The sensitivities calculated by sEnz cover enzymes, reactions and protein sectors, enabling a holistic overview of the factors influencing metabolism. When applied to an Escherichia coli PAM, sEnz revealed major pathways and enzymes driving overflow metabolism. Overall, sEnz offers a computational efficient framework for understanding PAM predictions and unraveling the factors governing a particular metabolic phenotype. sEnz is implemented in the modular toolbox for the generation and analysis of PAMs in Python (PAModelpy; v.0.0.3.3), available on Pypi (https://pypi.org/project/PAModelpy/). The source code together with all other python scripts and notebooks are available on GitHub (https://github.com/iAMB-RWTH-Aachen/PAModelpy).

Dynamic pricing and inventory model for perishable products with reference price and reference quality

Reference price (quality) is a benchmark point used by consumers to make price (quality) judgements. Combining reference price and reference quality with dynamic pricing and inventory management, this paper applies differential equations theory to construct a optimal control model for perishable products when the quality of products declines exponentially. The demand of products depends on price, quality, reference price and reference quality, among which reference price and reference quality are influenced by consumers’ past memory. The aim is to maximize the retailer’s profit during the period. The conclusions are as follows. Firstly, a optimal dynamic pricing and inventory model for perishable products with reference price and reference quality is constructed, and the model is extended to dual decision variables, stochastic demand, time-dependent effects, competitive and infinite planing horizon setups. Secondly, through the Pontryagin maximum principle, the analytical expression of the optimal dynamic price is derived. Thirdly, a linear search method to solve the optimal static price is proposed. Finally, the sensitivity of the main parameters is analyzed and the corresponding management enlightenments are given. By comparison of dynamic and static pricing, we find that dynamic pricing can achieve more profits and take a shorter selling period. In addition, for the sales problem of perishable products affected by both reference price and reference quality, retailers should adopt skimming pricing strategy (the optimal price decreases with time). Furthermore, to obtain more profit, retails should strive to increase the sensitivity coefficients of two types of reference, and the reference quality memory coefficient, while to decrease the reference price memory coefficient.

Spatiotemporal dynamics and driving factors of ecosystem services value in Lanzhou City, China

Aligned with the imperatives of national ecological civilization construction, the systematic investigation into the intricate interplay between shifts in land utilization and the assessment of ecosystem services plays a pivotal and indispensable role in advancing ecological civilization. This endeavor holds significant implications. It aids in optimizing the ecological landscape at the regional level and fosters harmonious coexistence between humanity and the natural world. The study utilizes land-use remote sensing interpretation data from three time periods (2000, 2010, and 2020) and employs various methodologies, including equivalent factor coefficient correction, sensitivity analysis, and spatial autocorrelation. The objective is to uncover the spatiotemporal dynamics of land-use changes and Ecosystem Service Value (ESV) in Lanzhou City. Furthermore, geographic detectors are applied to explore the driving factors influencing ESV spatial heterogeneity and their interactions. The research findings indicate the following: (1) From 2000 to 2020, grassland and cropland were the predominant land-use types in Lanzhou City, with cropland and urban land experiencing the most active changes. (2) ESV in Lanzhou City increased from 179.37 billion RMB in 2000 to 193.86 billion RMB in 2020, reflecting an ESV total growth rate of 8.07% and a gradual improvement in the ecological environment. Spatially, ESV exhibits a “west high, east low” distribution pattern, with the center shifting towards the northwest and southeast, gradually reducing spatial imbalance. (3) Analysis of ESV spatial autocorrelation reveals that high-high clusters are predominantly found within the Tulu Gou National Forest Park and the Xinglong Mountain National Natural Reserve, while low-low clusters are primarily concentrated in the central urban area of Lanzhou City. Over the period from 2000 to 2020, the spatial clustering effect of ESV within the study area has progressively intensified. 4)NDVI, precipitation, and GDP emerge as pivotal factors influencing spatial differentiation within Lanzhou City, with natural and societal elements exerting interactive effects on ESV spatial disparities. The research results integrate environmental considerations into the decision-making process, offering valuable insights for formulating targeted ecological protection policies in Lanzhou City. This study embodies concrete measures taken by Lanzhou City in practicing China’s concept of “green water and green mountains are golden silver mountains,” providing a theoretical basis for the harmonious and sustainable development of the ecological economy.

Experimental and numerical study on critical oxygen concentration for shale gas detonation induced by oxygen-enriched combustion

To improve the shortcomings of Shchelkin spiral in enhancing overpressure utilizing oxygen-enriched combustion-induced detonation (OEC-DET) has seldom been touched upon. Systematic experiments and simulations have been conducted to reveal the kinetic mechanism and critical conditions of OEC-DET. Longmaxi (LMX) and Cambrian (HWX) shale gases with 4 % and 20 % nitrogen content were selected as fuels. Explosion overpressure histories of 0.8, 1.0 and 1.2 equivalence ratio fuels at different oxygen concentrations were tested in a 90 L multiphase fuel detonation tube. Temperature sensitivity coefficients of combustion reactions were then supplemented by kinetic simulations. OEC-DET was demonstrated to be a manifestation of pressure wave development promoted by liquid–gas phase transition of H2O produced by OEC. One underlying mechanism is that the increase in oxygen concentration enhances the temperature sensitivity and H2O production rate, thus favoring the occurrence of OEC-DET. The critical oxygen concentration (COC) of OEC-DET in shale gas has been determined to be around 25 %–30 % herein. The lower the nitrogen content and equivalence ratio, the lower the COC. Both the explosion overpressure and pressure rise rate exhibit segmented linear and exponential growth with the increase of COC, and particularly the growth trend becomes accelerated after OEC-DET. Two COC prediction equations have thus been derived with an accuracy exceeding 90 % and these shed light on the thermal engineering such as in-situ methane deflagration fracturing.

How Accurate are Your Experimental Data? A More Accessible GUM-Based Methodology for Uncertainty Evaluation

A methodology for evaluating experimental uncertainty is presented. Based on the Guide to the Expression of Uncertainty in Measurement (GUM) in conjunction with a sensitivity analysis, this method readily applies to systems of various degrees of complexity. It consists of three steps: (1) to estimate each uncertainty contribution of the system based on GUM; (2) to determine the sensitivity of the calculated results to variations in each of the input measurands in turn, replacing the partial derivatives of the GUM with a purely numerical approach; and (3) to calculate the overall uncertainty using the error propagation principle. Furthermore, the calculated sensitivity coefficients enable a critical evaluation of the investigated system, allowing the detection of possible targeted improvements. For this reason, the presented method is called “the sensitivity analysis method.” This is applied to three case studies with increasing complexity: a mass calibration procedure, a volume calibration procedure, and a gravimetric densimeter characterized by a multi-parameter nonlinear measuring model. When possible, the results are compared to the GUM uncertainty framework or values available in the literature.

Transport coefficient sensitivities in a semi-analytic model for magnetized liner inertial fusion

Performance of magnetized liner inertial fusion (MagLIF) experiments is highly dependent on transport processes including magnetized heat flows and magnetic flux losses. Magnetohydrodynamic simulations used to model these experiments require a choice of model for the transport coefficients, which are the constants of proportionality relating driving terms, such as temperature gradients and currents, to the associated heat and magnetic field transport. The coefficients have been the subject of repeated recalculation using various methods throughout the years. Using a semi-analytic MagLIF model [McBride and Slutz, Phys. Plasmas 22, 052708 (2015)], we compare models for the transport coefficients provided by Braginskii [Reviews of Plasma Physics, edited by M. A. Leontovich (Consultants Bureau, New York, 1965), Vol. 1, p. 205], Epperlein and Haines [Phys. Fluids 29, 1029 (1986)], Ji and Held [Phys. Plasmas 20, 042114 (2013)], Davies et al. [Phys. Plasmas 28, 012305 (2021)], and Sadler et al. [Phys. Rev. Lett. 126, 075001 (2021)]. The choice of model modifies magnetic-flux losses caused by the Nernst thermoelectric effect and thermal conduction losses. We present simulated results from parameter scans conducted in order to compare the effects of the different models on parameters of interest in MagLIF. In some regions of parameter space, discrepancies of up to 38% are found in integrated quantities like the fusion yield. These results may serve as a guide for experimental validation of the various models, particularly as laser preheat energies and initial axial field strengths are increased on MagLIF experiments.

Passive wireless RFID strain sensor for directional-independent structural deformation monitoring

The advancement of Radio-frequency identification (RFID) sensor technology presents a novel approach to monitoring the health of structures. However, the traditional RFID antenna sensor encounters issues with limited sensitivity and strain measurement capabilities in a single direction. In this investigation, we propose, model, analyze, and test an enhanced wireless and passive RFID strain sensor that offers improved sensitivity to strains and quantifiable measurements in orthogonal directions. Theoretical analysis based on multiphysics elastodynamics and electromagnetics illustrating the resonant response and distribution of current field density between two sets of orthogonally installed sensors under applied stress. Our findings reveal that the RFID strain sensor exhibits characteristics to electromagnetically induced transparency like (EIT-like) effect, enabling independent and intensified measurement of strains both horizontally and vertically. Experimental data demonstrates a linear correlation between the shift in resonant frequency of the sensor antenna and transverse strains as well as longitudinal strains, with sensitivity coefficients measuring −1.76 kHz με−1 for transverse strain and 2.17 kHz με−1 for longitudinal strain respectively. Consequently, by accurately analyzing variations in resonant frequency it becomes possible to deduce both magnitude and direction of strains on the antenna effectively laying groundwork for future engineering applications.

Sensitivity and uncertainty analysis of neutron activation source terms based on statistical sampling method

The calculation of neutron activation source terms is an essential task in the radiation of nuclear reactors, and its sensitivity and uncertainty (S&U) analysis can help better identify and control the influencing factors and safety margin of activation source terms. In this paper, we studied the statistical sampling strategies for the S&U analysis of activation source terms, established the calculation process of sensitivity coefficient and uncertainty, and the S&U analysis module based on sampling methods was integrated for the proprietary developed activation computation program ABURN. Two sampling ways, Monte Carlo and Latin hypercube sampling treatments, were employed to figure out the cases of pure decay single chain, pure activation single chain, and complex reaction network. The sensitivity coefficients and uncertainty of nuclide inventory were evaluated by taking the uncertainty of decay constant or reaction cross-section into account. The simulation results indicate that after introducing the LHS sampling method, the activation calculation program ABURN can improve computational efficiency in sensitivity and uncertainty analysis. Subsequent results demonstrated that the sensitivity coefficients and uncertainty solutions based on the sampling methods in the ABURN program were in good agreement with the analytical solutions and the FISPACT program, which verified the accuracy of the approaches and program in this paper.