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The underwater multichannel analysis of surface wave (UMASW) is becoming an essential tool for surveying subbottom shear wave velocity. Current practice is limited to interpretation based on the fundamental mode. This paper investigates the full dynamic response of the underwater-multilayered structure under two different types of sources (impact and explosion). Fundamental solutions in the transformed domain, after applying both Fourier transform and Fourier–Bessel transform, are derived utilizing the global stiffness matrix method, analogous to a 1-D finite element approach. Solutions in the physical domain are then obtained using the fast and accurate Fourier series and Fourier–Bessel series approach proposed in this paper. The most attractive feature of this novel approach is that the expansion coefficients (or Love numbers) can be pre-calculated, saved, and repeatedly used for other field points. Through numerical analyses, we quantitatively investigate the effect of the water depth and source/receiver types/locations on different wave features (i.e., Scholte, fast-guided, and acoustic modes) from different perspectives (i.e., dispersion curve, Green’s function, frequency-velocity spectrum (FVS), and waveform). We find that (1) unlike the impact source, stronger acoustic waves can be produced by the explosive source, which sometimes causes difficulty in identifying the Scholte waves. (2) The acoustic and interface-guided waves exhibit distinct behaviors depending on the source and receiver locations. Scholte waves and fast-guided waves are weakened when the source and receivers are elevated far from the water/soil interface. Moreover, (3) the response of the Scholte wave can be enhanced by muting the direct acoustic waves. However, (4) the fast-guided wave may also arise in underwater surveys when the Vs of the underlying half-space is much higher than those of the upper layers, exerting a significant influence on the shallow water scenarios and posing challenges for correct mode identification. With the ability to model the entire wavefield (or FVS) that takes into account all propagation modes and the actual survey configuration, inversion can be performed by fitting the entire FVS. This approach eliminates the need to pick dispersion curves and provides a more accurate and stronger model constraint. [ABSTRACT FROM AUTHOR]

Magneto-electro-elastic (MEE) materials are a specific class of advanced smart materials that simultaneously manifest the coupling behavior under electric, magnetic, and mechanical loads. This unique combination of properties allows MEE materials to respond to mechanical, electric, and magnetic stimuli, making them versatile for various applications. This paper investigates the static and time-harmonic field solutions induced by the surface load in a three-dimensional (3D) multilayered transversally isotropic (TI) linear MEE layered solid. Green's functions corresponding to the applied uniform load (in both horizontal and vertical directions) are derived using the Fourier-Bessel series (FBS) system of vector functions. By virtue of this FBS method, two sets of first-order ordinary differential equations (i.e., N-type and LM-type) are obtained, with the expansion coefficients being Love numbers. It is noted that the LM-type system corresponds to the MEE-coupled P-, SV-, and Rayleigh waves, while the N-type corresponds to the purely elastic SH- and Love waves. By applying the continuity conditions across interfaces, the solutions for each layer of the structure (from the bottom to the top) are derived using the dual-variable and position (DVP) method. This method (i.e., DVP) is unconditionally stable when propagating solutions through different layers. Numerical examples illustrate the impact of load types, layering, and frequency on the response of the structure, as well as the accuracy and convergence of the proposed approach. The numerical results are useful in designing smart devices made of MEE solids, which are applicable to engineering fields like renewable energy. [ABSTRACT FROM AUTHOR]

Background: Studies have confirmed that osteoporosis has been considered as one of the complications of diabetes, and the health hazards to patients are more obvious. This study is mainly based on the Taiwan National Health Insurance Database (TNHID). Through the analysis of TNHID, it is shown that the combined treatment of traditional Chinese medicine (TCM) medicine in patients of diabetes with osteoporosis (T2DOP) with lower related risks. Methods: According to the study design, 3131 patients selected from TNHID who received TCM treatment were matched by 1-fold propensity score according to gender, age, and inclusion date as the control group. Cox proportional hazards analyzes were performed to compare fracture surgery, hospitalization, and all-cause mortality during a mean follow-up from 2000 to 2015. Results: A total of 1055/1469/715 subjects (16.85%/23.46%/11.42%) had fracture surgery/inpatient/all-cause mortality of which 433/624/318 (13.83%/19.93%/10.16%) were in the TCM group) and 622/845/397 (19.87%/26.99%/12.68%) in the control group. Cox proportional hazards regression analysis showed that subjects in the TCM group had lower rates of fracture surgery, inpatient and all-cause mortality (adjusted HR = 0.467; 95% CI = 0.225–0.680, P<0.001; adjusted HR = 0.556; 95% CI = 0.330–0.751, P<0.001; adjusted HR = 0.704; 95% CI = 0.476–0.923, P = 0.012). Kaplan-Meier analysis showed that the cumulative risk of fracture surgery, inpatient and all-cause mortality was significantly different between the case and control groups (all log-rank p<0.001). Conclusion: This study provides longitudinal evidence through a cohort study of the value of integrated TCM for T2DOP. More research is needed to fully understand the clinical significance of these results. [ABSTRACT FROM AUTHOR]

Spectral analysis of surface waves (SASW) and multichannel analysis of surface waves (MASW) are the two main active surface wave methods, and their common inversion schemes are effective mode (EM) inversion and fundamental mode (FM) inversion, respectively. The former has a more rigorous inversion scheme, which considers receiver locations and dynamic response, while the latter has a more convenient dispersion analysis and fast inversion process. This paper introduces an improved dynamic response solution for elastic layered media subjected to vertical load. It is fast, accurate, and unconditionally stable, facilitating the full-wavefield inversion in terms of the frequency–velocity spectrum (FVS). The MASW FVS inversion merges the convenience and robustness of MASW dispersion analysis with the rigorous inversion scheme adopted by SASW. It is based on the actual dynamic response at receiver locations and takes into account possible higher modes and nonRayleigh waves. In this study, various types of synthetic velocity profiles are used to compare the inversion results among three different inverted schemes (SASW EM, MASW FM, and MASW FVS inversion). The results indicate that, when phase-unwrapping in SASW is not problematic, SASW EM inversion and MASW FVS inversion are theoretically sounder and produce better inverted results than the MASW FM inversion, while the process of MASW FVS inversion is more convenient and robust. Finally, a field example is used to further demonstrate the advantages of FVS inversion and its applicability. [ABSTRACT FROM AUTHOR]

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Mathematical modeling of multilayered piezoelectric (PE) ceramic substantially acquires attention due to its distinctive advantages of fast response time, positioning, optical systems, vibration feedback, and sensors, such as deformation and vibration control. As such, fundamental solution of a PE structure is essential. This paper presents three-dimensional (3D) static and dynamic solutions (i.e. Green's functions) in a multilayered transversally isotropic (TI) PE layered half-space. The uniform vertical mechanical load, vertical electrical displacement, and horizontal mechanical load are applied on the surface of the structure. The novel Fourier-Bessel series (FBS) system of vector functions (which is computationally more powerful and streamlined) and the dual-variable and position (DVP) method are employed to solve the related boundary-value problem. Two systems of first-order ordinary differential equations (i.e. the LM- and N-types) are obtained in terms of the FBS system of vector functions, with these expansion coefficients being the Love numbers. A recursive relation for the expansion coefficients is established by using DVP method that facilitates the combination of two neighboring layers into a new one and minimizes the computational effort to a great extent. The corresponding physical-domain solutions are acquired by applying the appropriate boundary/interface conditions. Several numerical examples pertaining to static and dynamic response are solved, and the efficiency and accuracy of the proposed solutions are validated with the existing results for the reduced cases. The solutions provided could be beneficial to better developments of PE materials, configurations, fabrication, and applications in the future. [ABSTRACT FROM AUTHOR]

Background: Diabetes with co-existing bone fragility or osteoporosis is common in elderly patients, whereas is frequently underestimated. Methods: We conducted dual-energy x-ray absorptiometry (DXA) with 7-site skinfold (SF) and dominant hand grip strength measurements among patients with type 2 diabetes (T2DM) to assess their gender-specific associations. A total of 103 patients with T2DM (60 females and 43 males), aged between 50 and 80 years (median 68.0 years) were enrolled and 45 non-DM females were also included to compare with T2DM females. Results: Our results revealed osteoporosis was negatively correlated with grip strength in both genders, negatively correlated with lean mass solely in males and negatively correlated with fat mass (particular the gynoid fat mass and thigh SF thickness) in females. Via performing multivariable stepwise logistic regression, we identified grip strength in both genders and thigh SF thickness in females as predictors for osteoporosis. Receiver operating characteristic curve analysis further disclosed 20.5 mm female thigh skinfold thickness, 18.1 kg female grip strength and 29.0 kg male grip strength as reasonable cutoff levels for predicting osteoporosis in the Taiwanese patients with T2DM. Conclusions: Patients with T2DM presented gender-specific associations between osteoporosis, body composition and grip strength. Grip strength and thigh SF thickness might serve as predictors for detection of osteoporosis in patients with T2DM. [ABSTRACT FROM AUTHOR]

A real-time and durable system for scour process monitoring with sufficient spatial precision is in pressing need for bridge safety management. In light of this, an innovative bundled time domain reflectometry sensing cable was recently proposed to enhance the time domain reflectometry technique for scour monitoring. However, current development only dealt with the construction of bundled sensing cable and the corresponding new data reduction method. Before it can be put into practical use, issues related to the effect of hydrological conditions, long-distance measurement, and actual field implementation are yet to be investigated. This study used both numerical simulations and laboratory experiments to examine the time domain reflectometry signals in response to both scour and deposition in different water-level conditions. As a result, the first guideline of waveform classification and interpretation is newly proposed to validly determine scour depth under various field conditions. Since field measurements often come with significant signal attenuation from resistance loss of long cable and dielectric and conductive loss in the sensing section, numerical simulations and a series of full-scale experiments were also conducted to assess the time domain reflectometry scour measurement range. The maximum measurement range of the latest time domain reflectometry scour sensing cable was found to be about 6 m. Within this range, the maximum error of scour estimation is within 0.2 m. Considering the new findings, a field time domain reflectometry scour monitoring system using the bundled time domain reflectometry sensing cable was designed accordingly and implemented at a bridge for the first time. The monitoring system successfully captured the scour process during a storm event and revealed some practical issues for future improvement as well. [ABSTRACT FROM AUTHOR]

Quality control of jet grouting at large depth is a challenging task. An in-hole electrical resistivity method was recently shown to have high potential for assessing the diameter and integrity of jet grouting. To facilitate visualised inspection and practical use of the in-hole resistivity method for jet grouting, this study introduces a novel and practical tomographic approach. An analogous mapping approach from axially symmetric in-hole electrical resistivity tomography (ERT) to two-dimensional (2D) half-space surface ERT is proposed, allowing direct implementation of widely available 2D inversion software. A quantitative reduction method is also proposed to determine accurately the variation of column diameter from the inverted tomogram. Numerical simulations validate the proposed approach and show that the estimation error is within 10% when the electrode spacing is less than 1/5 of the column diameter. The spatial resolution and the effect of axially asymmetric condition are numerically investigated, the latter suggesting the importance of centralising electrodes in the soilcrete column. Two physical model tests are performed and verify the performance of the proposed method experimentally. [ABSTRACT FROM AUTHOR]

In the past decade, the 2D electrical resistivity tomography (ERT) has been extensively used in the investigation and monitoring of geotechnical engineering and environment engineering, but there are many uncertainties hidden behind its vivid color earth-resistivity profiles. In order to use the 2D ERT in the scale of geotechnical engineering effectively, the accuracy and spatial resolution capability of measurements must be enhanced, or at least these uncertainties should be mastered to avoid overreading the measurement results. There were seven common geological models built in this study to discuss the variance in spatial analysis capability of 2D electrical resistivity profiles under different geologic conditions. The findings show that the resolution capability of 2D electrical resistivity profiles was influenced by depth, and in different strata, it may be influenced by the resistivity ratio, layer depth, covering depth, interlayer thickness, tilt angle, medium size, and noise intensity. Generally speaking, the relatively low resistance stratum had better resolution capability; if the relatively high resistance stratum was located under the relatively low resistance stratum, its resolution capability declined. In different strata, the resolution capability may be degraded under the effect of different factors. In addition, any noise in the course of measurement resulted in a random jump of the electrical resistivity profile, which worsened as the noise increased. These circumstances should be paid special attention to avoid misrecognition of electrical resistivity profile images. [ABSTRACT FROM AUTHOR]

Electrical resistivity tomography (ERT) is one of the most widely used geophysical methods in geological, hydrogeological, and geo-environmental investigations. Although 3D ERT is now available, 2D ERT remains state-of-the-practice due to its simplicity in fieldwork and lower space requirements. 2D ERT assumes that the ground condition is perpendicular to the survey line and outside the survey line is homogeneous. This assumption can often be violated in conditions such as geologic strikes not perpendicular to the survey line and topographic changes or buried objects near the survey line. Possible errors or artifacts in the 2D resistivity tomogram arising from violating the 2D assumption are often overlooked. This study aimed to numerically investigate the boundary effects on 2D ERT under various simplified conditions. Potential factors including resistivity contrast, depth and size of buried objects, and electrode spacing were considered for the parametric studies. The results revealed that offline geologic features may project onto the 2D tomogram to some extent, depending on the aforementioned factors. The mechanism and implications of boundary effects can be drawn from these parametric studies. [ABSTRACT FROM AUTHOR]

Most dielectric spectroscopy techniques require careful system calibration, tedious measurement, specially designed probes, precise input source, and some even involved complicated inversion models. This paper proposed a rapid, robust, and model-free multiple reflection analysis (MRA) of time-domain reflectometry (TDR) signals to measure the complex dielectric permittivity (CDP) spectrum. The key to MRA approach is to decompose the first top reflection and the subsequent multiple reflections from TDR signal and to compare their spectral ratio (MRA ratio). This ratio was theoretically derived from the transmission line theory and found to be independent of source function and impedance mismatches in the leading sections. Based on this theoretical formulation, the CDP spectrum can be uniquely inverted from the measured MRA ratio through optimization and an iterated initial guess method. Numerical evaluations and experimental verifications had proven that MRA is a reliable algorithm for measuring CDP spectrum covering 10 MHz–1 GHz. Factors influencing the reliable frequency region were discussed and recommendations on enhancing CDP measurement was proposed for highly dispersive materials. The MRA approach enables dielectric spectroscopy to be conveniently conducted in both laboratory and field, without complicated system setup and calibration. [ABSTRACT FROM AUTHOR]

This study introduced two major contributions for freeway health monitoring during the pipe roof construction and subsequent excavation to enlarge an existing underpass. First, a horizontal-plane settlement indication system (HSIS) was developed to monitor inevitable settlement due to shallow overburden above the steel pipes. Second, the experience gained from the field monitoring program was detailed with emphasis on encountered problems and countermeasures for freeway safety decision-making. On the basis of two microelectromechanical systems tilt sensors embedded as a differential pair, HSIS effectively minimizes the effect of ambient temperature whose fluctuation was expected at shallow depth. The measurement accuracy (≤4 mm) and repeatability (≤0.05 mm) were verified experimentally. Thereby, three HSIS arrays were positioned in the freeway pavement to continuously detect local settlement and based on which to issue possible alarm. The RS485 data acquisition protocol, which is characterized by fast synchronized communication, was applied for HSIS to reduce the dynamic error due to heavy traffics. The observed settlement was close to the alarm threshold, which is considered as the combination effects of the simulated settlement and the penetrating deviation during the pipe roof construction. Furthermore, an approach to account for false vertical drift due to instability of the fixed point of HSIS was proposed such that the settlement behavior during excavation phase could be effectively described. The unique implementation is a benefit to further HSIS application in practice. [ABSTRACT FROM AUTHOR]

Time domain reflectometry (TDR) is a measurement technique based upon transmission line theory. The solutions of transmission line equations are reformulated in terms of independent physical properties, instead of coupled per-unit-length circuit parameters. The complete TDR response is effectively modeled by a non-uniform transmission line using the non-recursive ABCD matrix approach. Approaches to calibrate line parameters and perform TDR measurements based upon such model are introduced with an example on dielectric spectroscopy. TDR modeling in terms of decoupled physical parameters and non-recursive algorithm allows more convenient calibration of line parameters and facilitates interpretation of TDR measurements. [ABSTRACT FROM AUTHOR]

Dispersion analysis in surface wave testing is conventionally associated with a certain method of data acquisition, such as phase angle analysis in the two-station spectral analysis of surface wave (SASW) method and two-dimensional (2D) multistation wavefield transformation in the multistation analysis of surface wave (MASW) method. A new procedure has been developed to reconstruct the SASW data as MASW-imitating data, taking advantage of the 2D multistation wavefield transformation to better analyze the SASW data. Numerical simulations and a real-world example demonstrate the feasibility of this procedure, but also reveal an unwanted side effect associated with aliasing. A common-receiver survey is proposed for future experiments to eliminate this unwanted side effect and at the same time increase the lateral resolution. [ABSTRACT FROM AUTHOR]

Purposes: Disseminated intravascular coagulation (DIC) is a complex systemic thrombohemorrhagic disorder involving intravascular coagulation and hemorrhage. The aim of this study is to test whether static magnetic field (SMF) is effective in attenuating lipopolysaccharide (LPS)-induced DIC. Materials and methods: In vivo experiments were performed in this study using male BALB/cByJ mice. An intraperitoneal injection of 50 mg/kg LPS was shown to lead to approximately 50% mortality and this dose was used in subsequent experiments. To test the effects of SMF on the survival rate of LPS-induced animals, the mice were exposed to 0.25-T SMF for 2 h before LPS injection. In addition, the effect of a 2-h SMF treatment on the production of anti-inflammatory cytokines was evaluated. Results: In the first set of experiments, we found that the survival rate was higher in the SMF-exposed group than in the sham-exposed group. The circulating platelet (PLT) counts in the SMF-exposed mice were significantly higher than in the unexposed animals. However, no significant changes in inflammatory cytokine, including tumour necrosis factor-α (TNF-α), interleukin-1α (IL-1α), interleukin-6 (IL-6) and monocyte chemotactic protein 1 (MCP-1), in plasma were found after SMF treatment. The results from the second experiment showed that the plasma levels of interleukin-1 receptor antagonist (IL-1ra) were higher in the SMF-exposed group than in the sham group. Conclusions: Exposure to an SMF increases the plasma levels of IL-1ra. This effect may inhibit the reduction in PLT in plasma, resulting in prevention in LPS induced DIC. [ABSTRACT FROM AUTHOR]

Time domain reflectometry (TDR) technology has become a valuable tool for detecting displacements and locating shear planes in rock or soil slopes. It is based on transmitting an electromagnetic pulse into a coaxial cable grouted in rock or soil mass and watching for reflections of this transmission due to cable deformity induced by the ground deformation. Early detection of localized shear deformation in soft soils and quantifying the shear displacement using TDR remains a challenging work. The TDR response due to localized shear deformation is affected by cable resistance, soil-grout-cable interaction, and shear bandwidth. A comprehensive TDR wave propagation model considering cable resistance is introduced to model TDR response to cable deformity. Effects of the influencing factors on the relationship between the reflection spike and the shear displacement are investigated through laboratory tests and numerical simulations. The implications to enhancing TDR response and quantifying shear displacement are stressed. Practical suggestions are made, including procedure for correcting resistance effect, selection of cable and grout, and how to quantify shear displacement using TDR. [ABSTRACT FROM AUTHOR]

Purposes: Lipopolysaccharide (LPS) is one of the major substances initiating the immune host response in microbial infections that results in cytotoxicity. In terms of treatment of the immune response, research has been conducted on physical environments that can reduce LPS-induced damage. In this experiment, a long-term continuous static magnetic field (SMF) was used as a physical resource to reduce LPS-induced immune host response. Materials and methods: Cultured fibroblasts were challenged with LPS to initiate an inflammatory reaction. Cell viability and various proinflammatory cytokine levels were detected and compared between SMF and sham-exposed groups. Results: Our in vitro study revealed that, with LPS challenge, fibroblasts continuously exposed to a 0.4-T SMF for 12 h demonstrated higher cell viability compared to unexposed analogs. From cytokine test, the levels of LPS-induced interleukin-1β (IL-1β) in the SMF-exposed groups were significantly lower relative to their unexposed counterparts (p < 0.05). By contrast, SMF exposure tended to increase the level of LPS-induced IL-1 receptor antagonist (IL-1Ra) and IL-6. Conclusions: Our results suggest that SMF stimulation inhibits LPS-induced cytotoxicity through reduction of proinflammatory cytokines and increase in anti-inflammatory cytokines of NIH-3T3 cells. [ABSTRACT FROM AUTHOR]

Flavonoids are natural compounds found in food items of plant origin. The study examined systematically the interaction of structurally diverse dietary flavonoids with trace metal ions and the potential impact of dietary flavonoids on the function of intestinal cells. Spectrum analysis was first performed to determine flavonoid-metal interaction in the buffer. Among the flavonoids tested, genistein, biochanin-A, naringin, and naringenin did not interact with any metal ions tested. Members of the flavonol family, quercetin, rutin, kaempferol, flavanol, and catechin, were found to interact with Cu(II) and Fe(III). On prolonged exposure, quercetin also interacted with Mn(II). Quercetin at 1:1 ratio to Cu(II) completely blocked the Cu-dependent color formation from hematoxylin. When quercetin was added to the growth medium of cultured human intestinal cells, Caco-2, the level of metal binding antioxidant protein, metallothionein, decreased. The effect of quercetin on metallothionein was dose and time-dependent. Genistein and biochanin A, on the contrary, increased the level of metallothionein. The interaction between dietary flavonoids and trace minerals and the effect of flavonoids on metallothionein level imply that flavonoids may affect metal homeostasis and cellular oxidative status in a structure-specific fashion. [ABSTRACT FROM AUTHOR]

The use of time domain reflectometry (TDR) for real-time monitoring of bridge scour process has gone through several stages of development. The recently-proposed concept of bundled TDR sensing cable, in which two sets of insulated steel strands are twisted around and connected to a central coaxial cable to form a compact sensing cable, is a major change that has several advantages including the bottom-up sensing mechanism. Nevertheless, there is big room for improving its measurement sensitivity and signal to noise ratio (SNR). Changes in waveguide configuration also need to be made to avoid the adverse effect of insulation abrasion observed in field implementation. This study evaluated three new conductor and insulator configurations for constructing the sensing waveguide, including a balanced two-conductor waveguide (Type I), an unbalanced three-conductor waveguide with insulation coating on the middle conductor (Type II) and an unbalanced three-conductor with insulation coating on the two outer conductors (Type III). In all cases, the spacing between the two sets of steel strands (i.e., the waveguide conductors) was especially enlarged by replacing some steel strands with non-conductor wires to increases measurement sensitivity and avoid shorted conditions due to insulation abrasion. Experimental results show that Type III has the best performance on all counts. A new improved TDR sensing cable was hence proposed based on Type III configuration. Its performance was further evaluated by a full-scale experiment to take into consideration the long range of measurement in most field conditions. Detailed discussions on improvements of measurement sensitivity and SNR, limitation of sensing range, and mitigating the adverse effect of insulation abrasion are presented. [ABSTRACT FROM AUTHOR]

Summary: Scour monitoring is crucial for providing early warning of bridge safety and extending the knowledge of scour process. Traditional methods that rely on underwater instruments encounter difficulties in installation and operation in harsh fluvial environment. Time domain reflectometry (TDR)‐based scour sensing wire was recently introduced as a promising technique to improve field deployment and durability. This study focused on further improving the concept of TDR sensing wire for better sensor package and performance. An innovative bundled bottom‐up sensing cable was proposed to improve sensor durability and avoid the adverse effect of sensor fouling. The sensor durability is enhanced by twisting two sets of steel strands (as two opposing electrodes for the waveguide) around a coaxial cable into a composite sensing cable. The inner coaxial cable is introduced and armored by the sensing steel strands to direct TDR pulse to the bottom end before connecting to the sensing waveguide formed by steel strands for bottom‐up sensing. Furthermore, taking advantage of a new data reduction method by using time‐lapse differential waveform, robustness of system calibration and scour estimation is further enhanced. Experimental results revealed the optimal design of bundled TDR sensing cable, effectiveness of the bottom‐up sensing approach, and better performance of the differential waveform method. [ABSTRACT FROM AUTHOR]

Time-domain reflectometry (TDR) has been a powerful tool for measuring soil dielectric properties. Initiating from apparent dielectric constant ( K a ) measurement up until apparent and complex dielectric spectroscopies, the embedded information in the TDR signal can be extracted to inspire our understanding of the underlying dielectric behaviors. Multiple full waveform inversion techniques have been developed to extract complex dielectric permittivity (CDP) spectrum, but most of them involved prior knowledge of input function and tedious calibration. This rendered the field dielectric spectroscopy challenging and expensive to conduct. Dual reflection analysis (DRA) is proposed in this study to measure CDP spectrum from 10 MHz to 1 GHz. DRA is a simple, robust, model-free, and source-function free algorithm which requires minimal calibration effort. The theoretical framework of DRA is established and the necessary signal processing procedures are elaborated in this study. Eight materials with different dielectric characteristics are selected to evaluate DRA's performance, by using both simulated and experimental signals. DRA is capable of measuring non-dispersive materials very well, whereas dispersive materials require the assistance of a long-time-window (LTW) extraction method to further extend the effective bandwidth. The DRA approach is suitable for field applications that can only record a limited amount of data points and in-situ dielectric spectroscopy. [ABSTRACT FROM AUTHOR]