Quantitative Evaluation Parameters Research Articles

The feasibility of half-dose contrast-enhanced scanning of brain tumours at 5.0 T: a preliminary study

PurposeThis study investigated and compared the effects of Gd enhancement on brain tumours with a half-dose of contrast medium at 5.0 T and with a full dose at 3.0 T.MethodsTwelve subjects diagnosed with brain tumours were included in this study and underwent MRI after contrast agent injection at 3.0 T (full dose) or 5.0 T (half dose) with a 3D T1-weighted gradient echo sequence. The postcontrast images were compared by two independent neuroradiologists in terms of the signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and subjective image quality score on a ten-point Likert scale. Quantitative indices and subjective quality ratings were compared with paired Student's t tests, and interreader agreement was assessed with the intraclass correlation coefficient (ICC).ResultsA total of 16 enhanced tumour lesions were detected. The SNR was significantly greater at 5.0 T than at 3.0 T in grey matter, white matter and enhanced lesions (p < 0.001). The CNR was also significantly greater at 5.0 T than at 3.0 T for grey matter/tumour lesions, white matter/tumour lesions, and grey matter/white matter (p < 0.001). Subjective evaluation revealed that the internal structure and outline of the tumour lesions were more clearly displayed with a half-dose at 5.0 T (Likert scale 8.1 ± 0.3 at 3.0 T, 8.9 ± 0.3 at 5.0 T, p < 0.001), and the effects of enhancement in the lesions were comparable to those with a full dose at 3.0 T (7.8 ± 0.3 at 3.0 T, 8.7 ± 0.4 at 5.0 T, p < 0.001). All subjective scores were good to excellent at both 5.0 T and 3.0 T.ConclusionBoth quantitative and subjective evaluation parameters suggested that half-dose enhanced scanning via 5.0 T MRI might be feasible for meeting clinical diagnostic requirements, as the image quality remains optimal. Enhanced scanning at 5.0 T with a half-dose of contrast agents might benefit patients with conditions that require less intravenous contrast agent, such as renal dysfunction.

Distinguishing heart failure subtypes: the diagnostic power of different cardiac magnetic resonance imaging parameters.

The aim of this retrospective study was to explore the diagnostic potential of various cardiac parameters in differentiating between heart failure with preserved ejection fraction (HFpEF) and heart failure with mid-ranged and reduced ejection fraction (HFm + rEF), and to discern their relationship with normal cardiac function. This research encompassed a comparative analysis of heart failure subtypes based on multiple indicators. Participants were categorized into HFm + rEF, HFpEF, and control groups. For each participant, we investigated indicators of left ventricular function (LVEDVi, LVESVi, and LVEF) and myocardial strain parameters (GLS, GCS, GRS). Additionally, quantitative tissue evaluation parameters including native T1, enhanced T1, and extracellular volume (ECV) were examined.For comprehensive diagnostic performance analysis, receiver operating characteristic (ROC) curve evaluations for each parameters were conducted. HFm + rEF patients exhibited elevated LVEDVi and LVESVi and decreased LVEF compared to both HFpEF and control groups. Myocardial strain revealed significant reductions in GLS, GCS, and GRS for HFm + rEF patients compared to the other groups. HFpEF patients showed strain reductions relative to the control group. In cardiac magnetic resonance imaging (CMR) evaluations, HFm + rEF patients demonstrated heightened native T1 times and ECV fractions. Native T1 was particularly effective in distinguishing HFpEF from healthy subjects. Native T1, ECV, and myocardial strain parameters have substantial diagnostic value in identifying HFpEF. Among them, native T1 displayed superior diagnostic efficiency relative to ECV, offering critical insights into early-stage HFpEF. These findings can play a pivotal role in refining clinical management and treatment strategies for heart failure patients.

Recognition and detection of unusual activities in ATM using dual-channel capsule generative adversarial network

Real-time detection of human activity has become essential for monitoring and security of public spaces such as bank ATMs and workplaces, due to daily rise in criminal activities. Currently, monocular CCTV cameras that only record RGB video are used for monitoring such restricted areas. In addition to RGB data, the RGB + D sensor also offers depth information about the scene. To overcome the issue of online recognition of anomalous activities in Bank ATMs, a supervised deep learning method utilizing Dual-Channel Capsule Generative Adversarial Network (DCCGAN) and RGB + D sensor is proposed. The input RGB + D Dataset is given to super pixel motion detection method to find the region of interest (ROI). Motion detection is a significant stage examination of wide scene for background subtraction and foreground detection. After arranging the motion detection, its region is positioned frame by frame. Then, the detected ROI is given to fast discrete curvelet transform with the wrapping (FDCT-WRP) method. FDCT-WRP feature extraction method. These extracting features are supplied to Deep Convolutional Spiking neural network (DCSNN), which realize the object. RGB and depth video segments are used to create motion templates from the RGB + D data online video stream. These templates are trained on DCCGANs to identify distrustful events in current activity and categorized as normal and abnormal. Additionally, a unique RGB + D dataset is employed because there was no existing dataset available for analyzing human activity in ATMs. The proposed DUA-DCCGAN-ATM approach is assessed on qualitative with quantitative statistical evaluation parameters and identify suspect occurrence with 0.932 precision and 98.2 % accuracy. The detailed statistical analysis exemplifies that the proposed technique can identify distrustful events in a real-time online manner prior completing the anomalous activity.

Multi-stage hysteresis modelling of magnetorheological dampers and experimental verification

An accurate theoretical model is the basis for the structural design and parameter optimisation of magnetorheological dampers (MRDs). Owing to the inability of existing models to accurately describe the motion characteristics of MRDs in the entire region, a multi-stage hysteresis (MSH) model for low-frequency conditions was proposed. The MSH model comprised a magnetic chain model and Bi-Viscous model to describe the characteristics of the pre-yield and yield flow stages, respectively. The local loss and inertia effect were considered in the MSH model. Steady-state and transient finite element methods were combined to analyse the magnetic field distribution during MRD motion, and an equivalent weighted mean magnetic field hypothesis was proposed to reduce the quantisation error and time consumption. The experimental results demonstrate the prediction effectiveness of the MSH model. Moreover, the quantitative evaluation parameters of the flow and hysteresis regions were obtained and the variation trend of the MRD main design indices with the magnetic circuit parameters was analysed. The obtained velocity distribution parameters indicate a smooth transition of the stages in the MSH model from a qualitative perspective. The mixed mode incorporates the physical properties of the shear and flow modes, but cannot simply be regarded as a linear superposition of these two modes.

The role of quantitative gray-scale ultrasound histogram in the differential diagnosis of infected and non-infected hydronephrosis.

The early detection of infected hydronephrosis is critical before lithotripsy. A feasible and noninvasive diagnostic method is of considerable clinical attention. This retrospective study was performed to find some quantitative evaluation parameters of B-mode Gray-scale ultrasound histogram analysis that might assist the early diagnosis of infected hydronephrosis and test their diagnostic efficacy. The ultrasound images and clinical data of 245 patients with hydronephrosis were retrospectively analyzed. Image J software was applied to obtain the gray-scale maps and the analysis results of the signal strength. The difference in the data between the infected and non-infected groups and the diagnostic value of the parameters were calculated. In this retrospective study, 70 patients with infected hydronephrosis and 175 patients with non-infected hydronephrosis were enrolled. The echogenicity of internal effusion and the echogenicity ratio of infected cases were significantly higher than those of non-infected cases (p < 0.05). The cutoff values were 23.82 (AUC = 0.859) of echogenicity of internal effusion, while 0.27 (AUC = 0.832) of echogenicity ratio. The quantitative evaluation of gray-scale ultrasound histogram is an objective and reliable method in differentiating infected from non-infected hydronephrosis.

A deep journey into image enhancement: A survey of current and emerging trends

Image captured under poor-illumination conditions often display attributes of having poor contrasts, low brightness, a narrow gray range, colour distortions and considerable interference, which seriously affect the qualitative visual effects on human eyes and severely restrict the efficiency of several machine vision systems. In addition, underwater images often suffer from colour shift and contrast degradation because of an absorption and scattering of light while travelling in water. These unpleasant effects limits visibility, reduce contrast and even generate colour casts that limits the use of underwater images and videos in marine archaeology and biology. In medical imaging applications, medical images are important tools for detecting and diagnosing several medical conditions and ailments. However, the quality of medical images can often be degraded during image acquisition due to factors such as noise interference, artefacts, and poor illumination. This may lead to the misdiagnosis of medical conditions, which can further aggravate life threatening situations. Image enhancement is one of the most important technologies in the field of image processing, and its purpose is to improve the quality of images for specific applications. In general, the basic principle of image enhancement is to improve the quality and visual interpretability of an image so that it is more suitable for the specific applications and the observers. Over the last few decades, numerous image enhancement techniques have been proposed in the literature This study covers a systematic survey on existing state-of-the-art image enhancement techniques into broad classification of their algorithms. In addition, this paper summarises the datasets utilised in the literature for performing the experiments. Furthermore, an attention has been drawn towards several evaluation parameters for quantitative evaluation and compared different state-of-the-art algorithms for performance analysis on benchmark datasets. In addition, we discussed the recent areas of applications in image enhancement in detail. Lastly, we have also discussed numerous unresolved open problems and suggested possible future research directions. We believe that by putting forth all our efforts this study may presents a comprehensive resource for the future research.

How to Measure the Success or Failure Rate of a New Product Strategy in Competitive Markets

Abstract This paper attempts to present a method for determining the level of goal achievement corresponding to a marketing strategy formulated for a new product launched in a competitive market. The research method used in this paper is a literature review in the area of new product development (NPD) and marketing strategy. The obtained scientific results indicate the importance of measurement of the effects of a new product strategy and provide various new metrics in this field. In practice, the author proposes useful indicators to measure the effects of a new product strategy in competitive markets. Given the economic and marketing implications of the study, its originality concerns the results that provide the basis for the improvement of company’s efforts in effect measurement of a new product strategy and also marketing strategy in competitive markets. The present paper contains an overview of scientific works about new product competitiveness, and also proposes a modification of the method used to measure new product competitiveness on the marketplace. The research contribution to marketing sciences primarily includes the formulation of a set of real rates to measure success or fail rate of a new product strategy in a competitive market. The novelty of the research lies in the approach used to obtain quantitative parameters for evaluation of market competitiveness of a new product in various industries.

Feasibility study of improved median filtering in PET/MR fusion images with parallel imaging using generalized autocalibrating partially parallel acquisition

This study aimed to analyze the applicability of the improved median filter in positron emission tomography (PET)/magnetic resonance (MR) fusion images based on parallel imaging using generalized autocalibrating partially parallel acquisition (GRAPPA). In this study, a PET/MR fusion imaging system based on a 3.0T magnetic field and 18F radioisotope were used. An improved median filter that can set a mask of the median value more efficiently than before was modeled and applied to the acquired image. As quantitative evaluation parameters of the noise level, the contrast to noise ratio (CNR) and coefficient of variation (COV) were calculated. Additionally, no-reference-based evaluation parameters were used to analyze the overall image quality. We confirmed that the CNR and COV values of the PET/MR fusion images to which the improved median filter was applied improved by approximately 3.32 and 2.19 times on average, respectively, compared to the noisy image. In addition, the no-reference-based evaluation results showed a similar trend for the noise-level results. In conclusion, we demonstrated that it can be supplemented by using an improved median filter, which suggests the problem of image quality degradation of PET/MR fusion images that shortens scan time using GRAPPA.

Study on the quantitative evaluation parameter system for basic acupuncture manipulations based on 3D motion tracking technology

To establish a quantitative evaluation parameter system for basic acupuncture manipulations based on 3D motion tracking technology, and to further analyze the characteristics of acupuncture manipulation. The motion tracking system Simi Motion Ver.8.5 was used to collect parameters of acupuncture manipulations, so as to establish a quantitative evaluation system mainly in spatial control parameters, time control parameters and stability parameters. Based on the evaluation parameter system, data of acupuncture manipulations (even reinforcing-reducing manipulation using lifting-thrusting technique and twirling technique) were collected from 19 teachers majored in acupuncture-moxibustion, of which the characteristics were analyzed and were compared with the results tested by traditional ATP-Ⅱ acupuncture manipulation parameter determination apparatus (ATP-Ⅱ). The evaluation parameter system could quantitatively analyze the basic acupuncture manipulations in 3 aspects, i.e. space, time and stability. Acupuncture manipulations were performed by shifting the needle body in a certain range along X, Y and Z axes. The amplitude and speed of thumb movement were greater than those of index finger. The time-history of lifting was similar to thrusting, while the time-history of twirling to left was similar to twirling to right in even reinforcing-reducing manipulation. The coordinate-time curve of finger movement of the evaluation system had consistent wave pattern compared with the voltage-time curve generated by ATP-Ⅱ. The quantitative evaluation parameter system based on 3D motion tracking technology can objectively evaluate basic acupuncture manipulations, and show the characteristics of different manipulations and the movement details of finger joints.

Fracture effectiveness evaluation in ultra-deep reservoirs based on geomechanical method, Kuqa Depression, Tarim Basin, NW China

Onshore ultra-deep oil and gas resource is abundant, which has become the main area for exploration and development in the future. Fracture is an important factor affecting the development of ultra-deep reservoir, and its effectiveness, as a significant parameter for quantitative evaluation of the reservoir, determines the production. Taking the DB-4 ultra-deep gas reservoir in Kuqa Depression as an example, through geomechanical methods, the in situ stress distribution of the wellbore is determined by using drilling data and logging data. Based on the identification and quantitative characterization of fracture parameters, the stress state and shear slip trend of fractures are analyzed by three-dimensional Mohr's circle analysis technique and Mohr Coulomb criterion, so as to quantitatively evaluate the effectiveness of ultra-deep fractures. Based on above analysis, the fracture opening under the condition of fluid injection is simulated to establish the relationship between fracture effectiveness and oil and gas production capacity. The results show that the gas reservoir where Well X4 of DB-4 gas reservoir has a burial depth of more than 8,000m, a typical onshore ultra-deep gas reservoir, and it is in an environment with extreme strong in situ stress. For the Cretaceous target reservoir, the horizontal minimum principal stress ranges between 165–180 MPa and the horizontal maximum principal stress generally exceeds 200 MPa. Natural fractures of Well X4 are largely developed, and the wellbore fracture parameters show strong heterogeneity. The Well X4 has low fracture opening pressure and high fracture effectiveness on the whole. The production capacity of gas wells in the ultra-deep reservoir shows extremely obvious positively correlation with the effectiveness of fractures under the influence of in situ stress, while it has little influence on petrophysical properties such as porosity and reservoir thickness. Both the fracture effectiveness evaluation method and results of DB-4 ultra-deep gas reservoir is helpful to provide geological reference for the efficient development of ultra-deep oil and gas resources in Kuqa Depression, and it is of significance for similar ultra-deep fractured reservoirs in the world.

Evaluation of hydrocarbon resources of the Devonian terrigenous rock basin of Perm Region

The geological structure of the Devonian terrigenous complex within the Bashkirian arch located in the well-explored southern part of Perm Krai has been considered in the paper. Due to the limited extent and complex structure of the bulk of reservoir rock in the prospective horizons, these deposits are explored unevenly, usually alongside with the overlying oil and gas bearing complexes. On the basis of the performed analysis of systematic data, the authors justify quantitative parameters for evaluation of non-localized resources after the method of comparative geological analogies in the Devonian terrigenous deposits. The estimated quantity of hydrocarbon resources in the territory under study unequivocally defines it as prospective for exploration and discovery of reserves in the Devonian oil and gas bearing complex. Therefore, the authors have identified areas for priority prospect evaluation survey taking into account the extent of the most promising facies zones of deltaic channels and beach bars.

Lightweight and Amplitude-Free Ultrasonic Imaging Using Single-Bit Digitization and Instantaneous Phase Coherence.

In the field of ultrasonic nondestructive testing (NDT), the total focusing method (TFM) and its derivatives are now commercially available on portable devices and are getting more popular within the NDT community. However, its implementation requires the collection of a very large amount of data with the full matrix capture (FMC) as the worst case scenario. Analyzing all the data also requires significant processing power, and consequently, there is an interest in: 1) reducing the required storage capacity used by imaging algorithms, such as delay-and-sum (DAS) imaging and 2) allowing the transmission and postprocessing of inspection data remotely. In this study, a different implementation of the TFM algorithm is used based on the vector coherence factor (VCF) that is used as an image itself. This method, also generally known as phase coherence imaging, presents certain advantages, such as a better sensitivity to diffracting geometries, consistency of defect restitution among different views, and an amplitude-free behavior as only the instantaneous phase of the signal is considered. Some drawbacks of this method must also be mentioned, including the fact that it poorly reproduces planar reflectors and presents a lower signal-to-noise ratio (SNR) than amplitude-based methods. However, previous studies showed that it can be used as a reliable tool for crack-like defect sizing. Thus, a lightweight acquisition process is proposed through single-bit digitization of the signal, followed by a phase retrieval method based on the rising and falling edge locations, allowing to feed the phase coherence imaging algorithm. Simulated and experimental tests were first performed in this study on several side-drilled holes (SDHs) in a stainless steel block and then extended to an experimental study on angled notches in a 19.05-mm ( 3/4" )-thick steel sample plate through multiview imaging. Results obtained using the array performance indicator (API) and the contrast-to-noise ratio (CNR) as quantitative evaluation parameters showed that the proposed lightweight acquisition process, which relies on binary signals, allows a reduction of the data throughput of up to 47 times. This throughput reduction is achieved while still presenting very similar results to phase coherence imaging based on the instantaneous phase derived from the Hilbert transform of the full waveform. In an era of increasing wireless network speed and cloud computing, these results allow considering interesting perspectives for the reduction of inspection hardware costs and remote postprocessing.

FRACTAL CHARACTERISTICS OF LOW-PERMEABILITY SANDSTONE RESERVOIRS

The sandstone micro-structure is one of the most important parameters for quantitative evaluation of groundwater/oil/gas resources and prediction of flow rates of water/oil/gas. In this study, we applied seven low-permeability sandstone samples obtained from North China to study the structures of pore and solid phase based on digital core technology and the fractal theory. In this work, rock images were collected by scanning electron microscopy (SEM), and then image software (image pro plus) was applied to convert the SEM images into binary images and calculated the perimeter and area of pores and particles. Using the fractal medium criterion, we analyzed the fractal characteristics of pore and solid phases, and then we extended the criterion from the pore phase to both pore and solid phases. This paper explores the relationship among the pore and solid phase fractal characteristics, porosity, pore size, particle size and fractal dimensions for pores and particles. The results were compared with the experimental data and showed that the solid phase satisfies the fractal distribution, while the pore phase dissatisfies the fractal distribution. It was also found that the minimum and maximum pore and particle sizes, magnification times have a significant effect on the results. In addition, by introducing the diameter and mean hydraulic radius into Ergun–Wu equation, the permeabilities of the samples were calculated.

Analysis of Microstructure and Low Permeability with 3D Digital Rock Modeling

The sandstone microstructure and permeability are important parameters for quantitative evaluation of groundwater/oil/gas resources and prediction of flow rates of water/oil/gas. In this study, we applied seven low-permeability sandstone samples obtained from North China to research the microstructure and permeability based on digital core technology. Rock images were collected by X-ray microcomputed tomography (μCT), and then software (Avizo) was applied to analyze the microstructure and calculate the parameters such as porosity, connected porosity, average equivalent diameter, tortuosity, and shape factor. By introducing the shape factor into the Kozeny–Carman equation, we modified the Kozeny–Carman equation and found that the modified equation is a function of porosity, diameter of particles, tortuosity, and particle shape factor.

Quantitative Fluorescence Imaging of Perfusion-An Algorithm to Predict Anastomotic Leakage.

This study tests fluorescence imaging-derived quantitative parameters for perfusion evaluation of the gastric tube during surgery and correlates these parameters with patient outcomes in terms of anastomotic leakage. Poor fundus perfusion is seen as a major factor for the development of anastomotic leakage and strictures. Fluorescence perfusion imaging may reduce the incidence of complications. Parameters for the quantification of the fluorescence signal are still lacking. Quantitative parameters in terms of maximal intensity, mean slope and influx timepoint were tested for significant differences between four perfusion areas of the gastric tube in 22 patients with a repeated ANOVA test. These parameters were compared with patient outcomes. Maximal intensity, mean slope and influx timepoint were significantly different between the base of the gastric tube and the fundus (p < 0.0001). Patients who developed anastomotic leakage showed a mean slope of almost 0 in Location 4. The distance of the demarcation of ICG to the fundus was significantly higher in the three patients who developed anastomotic leakage (p < 0.0001). This study presents quantitative intra-operative perfusion imaging with fluorescence. Quantification of the fluorescence signal allows for early risk stratification of necrosis.

Quantitative evaluation of liver function with gadoxetic acid enhanced MRI: Comparison among signal intensity-, T1-relaxometry-, and dynamic-hepatocyte-specific-contrast-enhanced MRI- derived parameters

Aims Three types of gadoxetic acid enhanced MRI parameters have been proposed to quantify liver function. However, until now there is no consensus on which one that has the greatest potential for use in clinical practice. This study was conducted to compare the efficacy of three types of gadoxetic acid enhanced MR parameters for quantitative assessment of liver function. Methods Imaging data of 10 patients with chronic liver disease and 20 healthy volunteers were analyzed. Parameters based on signal intensity(SI), T1 changes or dynamic-hepatocyte-specific-contrast-enhancement MR were calculated. Their mutual correlations, discriminatory capacity between cirrhotic and healthy liver and correlations with Child-Pugh score and Model for end-stage liver-disease (MELD) were estimated. Results The strongest correlations were observed between relative enhancement of the liver and T1 time at 20 min after contrast agent injection, and between liver-spleen contrast ratio at 20 min after contrast agent injection and hepatic uptake rate (|r|> 0.90, p < .05, both). All parameters but input-relative blood flow (p = 0.17) were significantly different between patient and control group (p < .05), with AUROCs of liver-to-muscle ratio (LMR), increase of LMR and hepatic extraction fraction greater than 0.90 (p < .05). Liver-to-spleen ratio, LMR and hepatic uptake index presented a strong correlation with Child-Pugh score and MELD (|r|> 0.8, p < .05). Conclusion Simple SI-based parameters were as good as more complex parameters in evaluating liver function at gadoxetic acid enhanced MR. In clinical routine LMR seems to be the easiest-to-use parameter for quantitative evaluation of liver function.

Analysis of Discrete Wavelet Transforms Variants for the Fusion of CT and MRI Images

Background: Medical image fusion methods are applied to a wide assortment of medical fields, for example, computer-assisted diagnosis, telemedicine, radiation treatment, preoperative planning, and so forth. Computed Tomography (CT) is utilized to scan the bone structure, while Magnetic Resonance Imaging (MRI) is utilized to examine the soft tissues of the cerebrum. The fusion of the images obtained from the two modalities helps radiologists diagnose the abnormalities in the brain and localize the position of the abnormality concerning the bone. Methods: Multimodal medical image fusion procedure contributes to the decrease of information vulnerability and improves the clinical diagnosis exactness. The motive is to protect salient features from multiple source images to produce an upgraded fused image. The CT-MRI image fusion study made it conceivable to analyze the two modalities straightforwardly. Several states of the art techniques are available for the fusion of CT &amp; MRI images. The discrete wavelet transform (DWT) is one of the widely used transformation techniques for the fusion of images. However, the efficacy of utilization of the variants of wavelet filters for the decomposition of the images, which may improve the image fusion quality, has not been studied in detail. Therefore the objective of this study is to assess the utility of wavelet families for the fusion of CT and MRI images. In this paper investigation on the efficacy of 8 wavelet families (120 family members) on the visual quality of the fused CT &amp; MRI image has been performed. Further, to strengthen the quality of the fused image, two quantitative performance evaluation parameters, namely classical and gradient information, have been calculated. Results: Experimental results demonstrate that amongst the 120 wavelet family members (8 wavelet families), db1, rbio1.1, and Haar wavelets have outperformed other wavelet family members in both qualitative and quantitative analysis. Conclusion: Quantitative and qualitative analysis shows that the fused image may help radiologists diagnose the abnormalities in the brain and localize the position of the abnormality concerning the bone more easily. For further improvement in the fused results, methods based on deep learning may be tested in the future.

Role of Shear Wave Elastography of Synovium to Differentiate Rheumatoid and Tubercular Arthritis.

Background:Synovitis is the underlying pathology in various arthritis, and sometimes, it is difficult to differentiate various arthritis clinically or even by imaging. The purpose of our study was to use shear wave elastography (SWE) to evaluate rheumatoid arthritis (RA) and tubercular (TB) arthritis and to differentiate them using synovial stiffness.Methods:The prospective study was performed on Supersonic Imagine Aixplorer Ultrasound (USG) machine using a linear array probe SL10-2 (2–10 MHz). A total of 29 participants, 15 of RA (ACR/EULAR criteria) and 14 of proven TB arthritis were included. Region of interest of 1 mm was applied on the hypertrophied synovium and quantitative SWE data in form of elasticity (kPa) and velocity (m/s) were measured. Discrete categorical data were presented as n (%). Mean values were recorded along with standard deviation and the range of values. To find a maximal cutoff value of elasticity and velocity - receiver operating characteristic curve were plotted.Results:The mean elasticity and velocity values were 54.81 ± 10.6 kPa and 4.2 m/s ± 0.42 for RA and 37 ± 10 kPa and 3.4 ± 0.47 m/s for TB group. Significant difference (P < 0.001) was seen in elastic modulus values between rheumatoid and TB group with cutoff of 43.6 kPa to differentiate the two groups (sensitivity – 86.7% and specificity – 80%). Similar significant (P < 0.001) results were seen with velocity values, with cutoff of 3.76 m/s (sensitivity – 86.7% and specificity – 80%).Conclusion:SWE shows the potential to be a useful adjunct to gray scale and color Doppler USG in differentiating various arthritis on the basis of elastic properties of the synovium. Elastic modulus and velocity are useful SWE quantitative parameters for synovial evaluation and can differentiate RA and TB arthritis.

Development of technology for determining the face shotcrete thickness by logistic regression

The authors have been studying to evaluate the risk of rock falling from the face in consideration of the geological condition of the face and the face shotcrete thickness using logistic regression in order to prevent the face falling accident in tunnel excavation. This technique estimates the risk of rock falling by a logistic function obtained from computer jumbo drilling data, quantitative evaluation of weathering and cracks by image analysis of the face, and face shotcrete thickness as parameters. In this paper, the authors report the results of collecting data at a tunnel site of slate and sandstone and examining the method of determining the face shotcrete thickness according to the ground conditions using the logistic function. The logistic function that calculates the face falling probability obtained by logistic regression is transformed into a function that calculates the face shotcrete thickness by inputting the geological quantitative evaluation parameters and assuming the presence of rock falling at the probability of 50%. By using this function, it is possible to output the face shotcrete thickness to prevent rock falling by inputting the quantitative geological evaluation values of the face. As a result of examining slate and sandstone tunnel, the accuracy of determining the occurrence of rock falling was 69%.

Experimental study on the micro-mechanism for strength degradation of deep-sea soft soil

In this study, the cyclic strength degradation mechanism of deep-sea soft soil is investigated from a microscopic perspective. To explore this problem, a series of cyclic penetration tests are carried out for reconstituted soil by proved T-bar penetrometer to obtain the variations of strength under cycle loading. The undrained shear strength for reconstituted deep-sea soft soil degrades under cycle loading and eventually tends to be stable. At the same time, the SEM images are got at different stages. A new quantitative evaluation parameter of microstructure (probability entropy, H) is defined to analyze the changes of soil microstructure. In the continuous cyclic penetration process, the H of reconstituted deep-sea soft soil first increases and decreases after a maximum value. Based on the T-bar penetrometer tests and probability entropy results, the cyclic strength degradation mechanism is proposed. The process of cyclic strength degradation is that the microstructure is constantly destroyed, and eventually a stable structure with uniform particle shape and direction is formed.