Actual Width Research Articles

A low sampling rate method for the monopole UWB impulse parameter monitoring using waveform transformation

In ultra-wideband (UWB) impulse parameter monitoring, amplitude and pulse width measurements are crucial for detecting and classifying unknown impulse signals. Meanwhile, mass sampling data and the complexity of the current measurement technologies are the limitations of real-time and continuous monitoring. It urges to adopt a simple method that reduces the sampling rate without sacrificing accuracy. This article suggests a novel approach for the monopole UWB by analog signal preprocessing before sampling. A peak detector and integrator are utilized to retain the impulse amplitude and the area inside the impulse for a period, which is the so-called waveform transformation. A low-speed two-channel synchronous ADC samples the output signals from the peak detector and the integrator to determine the amplitude and the area. In the signal process, we demonstrate the concept that pulse width value equals the division of area and amplitude. Due to the distorted amplitude caused by the response time of the peak detector, the relationship between the distorted amplitude, the actual amplitude, and the pulse width is analyzed and examined based on the response function. Finally, the actual amplitude and pulse width are acquired and calculated by solving two equations. In terms of impulse waveform, rectangular and Gaussian waveform factors are developed and applied in the measurement. The proof-of-concept experimental results of a 0.68 V/ 18.8 ns rectangular impulse at a 10 Msps sampling rate is 0.711 V/ 17.00 ns with 4.56 %/ 9.57% relative error, tested and verified.

Effect of 3D laser point spacing on cement concrete crack width measurement

The objective of this paper is to examine the reliability of three-dimensional (3D) laser detection technology data density for crack width detection results of cement slabs. Four groups of cement concrete crack elevation data with a laser data density of 0.5–1.5 mm were obtained using an indoor 3D laser detection system, and 3D models were established. The nonlinear least squares method was applied to fit the fracture section, and the crack width was determined by the peak value analysis. The results demonstrate that the lateral spacing of laser points exerts a large impact on the mean and discrete degrees of cement concrete crack width detection results. The laser point spacing is positively correlated with crack identification errors. Insufficient laser accuracy leads to an overestimation of crack severity level and affects the accuracy of pavement damage condition evaluation. High-precision laser equipment exhibits certain reliability for detecting cement concrete crack width above 3 mm. In the actual pavement crack width detection process, the appropriate transverse spacing of laser points can be selected according to different error limit requirements to fulfill the requirements of both detection reliability and data processing efficiency. Suggestions for future research include expanding the experimental conditions, increasing the 3D laser point spacings, and selecting more road lanes and pavement materials to further examine the influential factors of pavement crack width measurement.

Research on the Method of Reducing Dynamic Cutting Force in Aspheric Machining.

With the rapid development of photoelectric communication and other fields, the demand for high-precision aspheric mirrors has been increasing. Predicting dynamic cutting forces is vital in selecting machining parameters and also affects the surface quality of the machined surface. This study comprehensively considers the effects of different cutting parameters and workpiece shape parameters on dynamic cutting force. The actual width of cut, depth of cut, and shear angle are modelled while considering the effects of vibration. A dynamic cutting-force model considering the aforementioned factors is then established. Using experimental results, the model accurately predicts the average value of dynamic cutting force under different parameters and the range of fluctuation of dynamic cutting force, with a controlled relative error of about 15%. The influence of workpiece shape and workpiece radial size on dynamic cutting force is also considered. The experimental results show that the greater the surface slope, the more dramatic the dynamic cutting force fluctuations. This lays the foundation for subsequent writing on vibration suppression interpolation algorithms. The influence of the radius of the tool tip on dynamic cutting forces leads to the conclusion that to achieve the goal of reducing the fluctuation of cutting forces, diamond tools with different parameters should be selected for different feed rates. Finally, a new interpolation-point planning algorithm is used to optimize the position of interpolation points in the machining process. This proves the reliability and practicability of the optimization algorithm. The results of this study are of great significance to the processing of high-reflectivity spherical/aspheric surfaces.

Radiological assessment of facial recess and correlation with surgical measurement in cochlear implantation

BackgroundThe facial recess (FR) is the crucial landmark in posterior tympanotomy approach which is the conventional approach for cochlear implantation surgery. This work aimed to measure the facial recess width and length radiologically and correlate these measurements with the surgical measurements in cochlear implantation procedure. An observational cross-sectional study was conducted on one hundred patients with sensorineural hearing loss prepared for cochlear implantation according to health insurance regulations. Patients included in the study were subjected to the following protocol: a routine ENT examination formed the initial part of the evaluation, audiological tests for adults and children were done, and the radiological evaluation for the patients included high-resolution computed tomography (HRCT) scanning [axial plane, oblique sagittal plane, and curved multiplanar reconstruction (MPR CT)]. These HRCT images were used to measure the facial recess width and length. Measurement of the FR width and length was done intraoperative by using a sterile ruler. Radiological measurements were correlated with the surgical measurements.ResultsThere was a statistically significant correlation between FR width surgically and FR width radiologically (p-value < 0.001). FR width measured in CT axial cuts, curved MPR images, and oblique sagittal cuts could predict FR width surgically. There was a statistically significant correlation between FR length surgically and FR length radiologically (p-value < 0.001). There was no statistically significant correlation between age and sex on one hand and surgical and radiological measurements on the other hand.ConclusionPreoperative HRCT axial plane, oblique sagittal plane, and curved MPR CT can predict actual facial recess width and length.

Pixel‐level thin crack detection on road surface using convolutional neural network for severely imbalanced data

AbstractBecause roads are the major backbone of the transportation network, research about crack detection on road surfaces has been popular in computer and infrastructure engineering. When training a convolutional neural network (CNN) for pixel‐level road crack detection, three common challenges include (1) the data are severely imbalanced, (2) crack pixels can be easily confused with normal road texture and other visual noises, and (3) there are many unexplainable characteristics regarding the CNN itself. When it comes to very fine and thin cracks, these challenges are exaggerated and a new challenge is introduced, as there can be a discrepancy between the actual width and the annotated width of a crack. To tackle all these challenges of thin crack detection, this paper proposes a new variant of CNN named ThinCrack U‐Net, designed to provide thin results upon pixel‐level crack detection on road surfaces. The main contribution is to demystify how pixel‐level thin crack detection results are affected by different loss functions as well as various combinations of the U‐Net components. The experimental results show that ThinCrack U‐Net yields a significant performance boost in CrackTree260, from 65.71% to 94.48% F‐measure, compared to the existing variant of U‐Net previously proposed in the context of pixel‐level thin crack detection. Finally, this paper locates the source of undesirable result thickness and solves it with the balanced usage of downsampling/upsampling layers and atrous convolution. Unlike suggested by previous works, different loss functions show no significant impact on ThinCrack U‐Net, whereas normalization layers are proved crucial in pixel‐level thin crack detection.

Heteroatomic stitching of broken WS2 monolayer with enhanced surface potential.

Sub-nanometre thick two-dimensional (2D) materials suffer from severe cracking during the high temperature chemical vapour deposition growth process. The cracking can be utilised to generate more active edges. These active edges can be stitched with a homo- or hetero-material. While the direct growth of 2D-heterostructures is mostly limited to a small fraction of outer edges of monolayer flakes, the cracked monolayers can be utilised to produce a large fraction of heterostructures. Heterostructures are important for developing multifunctional components for nanoscale electronics and optoelectronics. In this work, we demonstrate the formation of WS2-MoS2 heterostructures in large fractions by atomic stitching of cracked WS2 monolayers with the sequential growth of MoS2. Aberration-corrected scanning transmission electron microscopy and Raman spectroscopy have been utillised to probe fine details on the stitched interface between WS2 and MoS2. Growth of MoS2 domains were observed to take place at the terminating edge of cracked WS2, which then merged to form MoS2 multilayers at the cracked site. Growth of MoS2 at the opposite edges of WS2 eventually results in a MoS2-MoS2 junction with a Σ = 7 tilt boundary. Kelvin probe force microscope (KPFM) measurement from the stitched region revealed that the work function of WS2 is ∼32.46 meV higher than that of MoS2, which also closely matches with the Fermi energy difference between these two materials. With the aid of an atomic force microscope and KPFM, the surface potential width at the stitched region was found to be ∼5 times higher than the actual width of the interface, confirming the modulation of properties near the interface.

Rice seed size measurement using a rotational perception deep learning model

The size of the rice seed is one of the most important traits affecting rice yield quality. Some drawbacks are inherent in the current automated seed measurement technology: First, the seed must be preprocessed prior to measurement. Secondly, a large overlap of seeds is not permitted. And thirdly, it is slow to take pictures using equipment such as scanners. To address these issues, we propose a rotational perception deep learning model YOLO-rot for automatic seed number and size measurement in this work. The YOLO-rot algorithm is divided into four major steps: (1) Image partition. (2) Full seed detection, where the data representation, the detection module, the IOU evaluation, the non-maximal suppression algorithm, and the loss function included in the YOLOv5 model are all improved. (3) Fuse the detection results. (4) Determine the actual length and width of each seed. We evaluated the impact of two different photographic methods and overlap rates on the detection accuracy of the YOLO-rot model. The results of the experiment indicated that mAP@0.5 reaches a maximum value of 0.92 when the number of overlapping pixels between subimages is 250. And the performance of YOLO-rot was compared with ImageJ, GrainScan, and GridFree. The MSE of length and width estimates was not greater than 0.11 using the YOLO-rot model for all 900 seeds. The promising results of this research have led to the development of an application tool for automatic seed measurement in real time.

Bandgap prediction for a beam containing membrane-arch-mass resonators

This work aims to propose a promising locally resonating system consisting of a tensioned elastic membrane and two-arch masses attached on the membrane surface. Traditional membrane-type resonators, which usually create one obvious attenuation zone at low frequencies, might not be efficient in multi-frequency vibration suppression. The proposed structure can produce an extra clear flexural attenuation region and shift bandgap frequencies below 300 Hz. By adjusting geometric parameters (thickness, width, and location) of the arch mass, the bandgap region can be tuned. Introducing a feasible analytical model for accurately predicting the first and second initial frequencies of the bandgaps for a beam structure containing membrane-arch-mass resonators is another focus of this study. The proposed theoretical framework can be used to tune the bandgap to different target frequency ranges without knowing the actual width of the bandgap. Finite-element analysis and experiments are conducted to verify the theoretical predictions. A good agreement is seen among the theoretical, finite-element analysis, and experimental results. In addition, adjacent cells with different arch-mass distributions can generate two pairs of flexural bandgaps, increasing the practicality in engineering applications. The proposed structure might be used in low-frequency vibration isolation and filters.

Interaction between two horizontal axis tidal turbines in model scale – experiment and simulation

Up to 6 Schottel Instream Turbines (SIT250) can be mounted on the tidal platform PLAT-I developed by Sustainable Marine Energy. Due to the close proximity of the turbines interactions can occur between them. Two horizontal axis tidal turbines in model scale are investigated experimentally and numerically to analyze these interactions. Experimental data were measured in a towing tank and consist of integral values for torque, thrust and rotational speed. Both a steady state and an unsteady three-dimensional Reynolds Averaged Navier Stokes (RANS) approach are utilized for simulating the turbine flow field. The first part of the paper compares simulation results of a single turbine at different tip speed ratios with measurements to validate the numerical approach and its employed models. The second part analyses the interaction between two turbines. The axial distance in main flow direction between the turbines is half the rotor diameter. The radial distance measured between the hubs of the turbines is varied in steps of 0.2 between 0.0 and 2.0 times the rotor diameter in the experiment and between 0.0 and 1.4 in the simulations. Measurements were conducted for tip speed ratios of 3, 4 and 5. In the simulations the tip speed ratio was fixed at 4. The used simulation domain replicates the actual width and height of the towing tank and a sufficient length up- and downstream of the turbines. The water surface is modeled with a free slip wall. Both thrust and torque are compared between simulation results and experimental data. Furthermore, a detailed analysis of the results and flow field in the numerical simulations is presented and the interaction between the turbines is discussed.

The role of volatile organic compounds in the oxidation-driven fragmentation of soot particles

In this work, the role of volatile organic compounds (VOCs) in soot oxidation and fragmentation was investigated in a lean, premixed CH4 flame. An aerosol generator was used to homogeneously disperse soot with and without VOCs (termed Soot-W and Soot-WO, respectively) into the flame. Because minimal soot was formed in the flame itself, information on the fragmentation of the Soot-W and Soot-WO during the oxidation process was readily captured to determine the role of VOCs in soot fragmentation. The integrated number concentration of fine mode particles and the degree of particle aggregation show that the presence of VOCs suppresses soot aggregate fragmentation, primarily by the mitigating consumption of the neck sites between primary particles due to the decreased specific surface area. The actual oxygen diffusion route and effective pore width between the crystallite structures were determined using the image analysis technique. To determine the characteristic regime of oxygen diffusion, the distribution of effective pore width was studied using high-resolution transmission electron microscopy and image analysis. The estimated effectiveness factor indicates that the presence of VOCs lowers the propensity of internal burning via intra-particle oxygen diffusion, and reduces the extent of primary particle fragmentation, as evidenced by a relatively smaller peak of ultrafine particles. The analysis of the nanostructure of neck sites vs. the bulk discovers significantly more disordered and thus reactive structure at neck sites, explaining the prevalence of aggregate fragmentation over primary particle fragmentation. The finding of the role of VOCs in oxidation-driven fragmentation is beneficial to the optimization of existing models for predicting the number concentration of fine and ultrafine particles. Furthermore, a better understanding of this role may aid in the control of the most harmful fine and ultrafine particle emissions.

СРАВНИТЕЛЕН АНАЛИЗ НА ШИРИНАТА НА ИВИЦАТА ЗА ЗАВИВАНЕ ПРИ ИЗВЪРШВАНЕ НА ГЪБОВИДНИ ЗАВОИ ОТ НАВЕСЕН МАШИННО-ТРАКТОРЕН АГРЕГАТ В ПОЛЕ С НЕПРАВИЛНА ФОРМА

Analytical relations for determining the headland width when making T-turns by a machine-tractor unit with a mounted machine on an irregularly-shaped field have been specified. Five types of T-turns are described in two variants – open turn and closed turn. Each of these is done in two directions of movement. A total of 20 variants of the turns are described. The method for determining the headland width of a specific machine-tractor unit consisting by a tractor and mounted row seeder is demonstrated. For each type of turn the headland width is determined according to the angle between the direction of movement of the agricultural unit and the field border. A range of angle modification from 10° to 90° is adopted. The analysis show that for obtaining minimum headland width closed turns in left to right direction of movement should not be made. The smallest theoretical headland width is when making a closed T-turn with arch-shaped backward movement and left-to-right direction of movement on the field. When using T-turns with an arch-shaped backward movement and T-turns with straight ahead movement when entering the headland, the actual headland width is the same (6 m) regardless of the type and direction of the turn.

Flow-structure interference effects with the surrounding structure in the choked quasi-steady condition of tsunami: Comparison with traditional obstruction approach

To understand tsunami flow interaction with the structure occupying a certain percentage of flow channel width in the field, several authors modelled experiments or numerical simulations with the single structure occupying the same obstruction ratio, denoted by b/W (b = single structure width; W = flow channel width, considered as flume width). This setup resulted from laboratory width constraints or computational time reduction in numerical modelling, leading to the inherent assumption of symmetrical flow conditions at the flume walls. In this study, we compare the flow and force characteristics of the b/W setup with the results from the unsteady flow-structure interaction experiments conducted along with the adjacent structures in the flow choked condition, thereby replicating a realistic flow behaviour (termed as b/W* setup, here W* represents the actual flow width replicating the real field). The results from the experiments indicate that the change in the bore height at the structure front (h*f) is marginal or almost negligible between the two setups, independent of Fr. However, the bore height at the structure backside (h*r) is significantly altered. The existence of the hydrostatic pressure at the structure front and backside still ensured F*≈ρbg(hf*2−hr*2)/2 in flow-choked condition for the b/W* setup. Further, the 'h*f' prediction using the conservation of mass and momentum equations is improved. In regards to the vertical uplift force (F*u), the ratio of F*u/F*ub (F*ub = buoyancy force calculated using the average of h*f and h*r in the b/W* setup) is found to be approximately 1.15 times higher than Fu/Fub in the b/W setup (Harish et al., 2022a).

An adaptive scalloping suppression method for spaceborne ScanSAR images based on pre-estimation and weighted filtering

Spaceborne scanning synthetic aperture radar (ScanSAR) is widely used in global observations due to its ability to perform wide-swath mapping in the range direction. However, its special working mode causes scalloping, which reduces the quality of images and affects subsequent applications. According to its characteristics, an adaptive method based on pre-estimation and weighted filtering is proposed in this paper to suppress scalloping in the image domain. First, the azimuth intensity distribution of the image after scalloping suppression is estimated, which is used for scene stationarity test. Then, the images that cannot meet the stationary standard are segmented into subimages using maximum entropy principle and mathematical morphology. Finally, an algorithm based on adaptive weighted filtering is introduced to suppress scalloping, and the suppressed subimages are fused to obtain final results. The performance of the proposed method is tested with real ScanSAR data from the Gaofen-3 (GF-3) satellite. The experimental results indicate that the effect of scalloping suppression is excellent, since the depth of scalloping can be suppressed to approximately 0.3 dB. Notably, the proposed system is efficient in processing large-area images, such as GF-3 ScanSAR images whose actual width is more than 300 km. The entire process requires no parameter adjustment, and the proposed method is suitable for various complex scenes. The effectiveness, high efficiency, adaptability and robustness of the proposed system are verified.

The Importance of the Maxillary and Mandibular Incisors in Predicting the Canines and Premolars Crown Widths.

Background The purpose of the present study was to use the combined mesiodistal crown widths of the mandibular and maxillary incisors as predictors for the combined mesiodistal crown widths of mandibular and maxillary canines and premolars. Materials and Methods One hundred and twenty pairs of study models belong to 120 Iraqi adult subjects with normal dental and skeletal relations were included in the study. The crown widths of the mandibular and maxillary incisors, canines, and premolars were assessed at the maximum mesiodistal dimension on the dental casts using a digital electronic caliper with 0.01 mm sensitivity. The correlation between combined mesiodistal crown widths of the mandibular and the maxillary incisors and combined mesiodistal crown widths of mandibular and maxillary premolars and canines has been determined using Pearson's coefficient correlation test for each arch and gender. Using simple regression analysis, the equations predicting the widths of the mandibular and maxillary premolars and canines were established. The predicted and the actual mesiodistal crown width values have been compared with the use of a paired sample t-test. Results According to the findings of the present study, males had significantly wider teeth compared to females. Correlations between the measured parameters ranged from moderate to strong. A nonsignificant difference between actual and predicted mesiodistal crown widths was discovered. Conclusions With a high degree of accuracy, the combined mesiodistal widths of the maxillary and the mandibular incisors could be utilized for predicting the combined mesiodistal crown widths of the mandibular and maxillary canines and premolars.

Multistage semisupervised active learning framework for crack identification, segmentation, and measurement of bridges

AbstractIn bridge health monitoring (BHM), crack identification and width measurement are two of the most important indices for evaluating the functionality of bridges. In order to reduce the labor cost in field detection, researchers have proposed a variety of deep learning (DL)‐based detection techniques for crack recognition. However, some problems still exist in extending these techniques to practical applications, such as data annotation difficulty, limited model generalization ability, and inaccuracy of the DL identification of the actual crack width measurement. In this paper, an application‐oriented multistage crack recognition framework is proposed, namely, Convolutional Active Learning Identification‐Segmentation‐Measurement (CAL‐ISM). It includes four steps: (1) pretraining of the benchmark classification model, (2) retraining of the semisupervised active learning model, (3) pixel‐level crack segmentation, and (4) crack width measurement. Beyond numerical experiments, the performance of the CAL‐ISM is validated for practical applications: (i) bridge column test specimen and (ii) field BHM projects. In conclusion, the obtained results from these applications shed light on the high potential of CAL‐ISM for BHM applications, which is recommended in future deployments for BHM.

Smartphone application-based measurements of stem-base width and plant height in rice seedling

The measurements of stem-base width and plant height in rice seedlings are significantly associated with the assessment of in-field seedling growth quality, the determination of optimal seedling transplanting time, and the decision-making of later fertilization use. At present, the measurements of such two morphological traits heavily rely on the inefficient manual measurement method. Herein, we develop a smartphone application to accomplish these tedious and repetitive measurement tasks. Using the developed smartphone application, the reference object and rice seedling were taken into an entire image and then were performed image pre-processing, thereby segmenting the foreground from the background. The reference object image and rice seedling image in the foreground were respectively separated via a comparison in heights of the foreground contours. The reference object image was used for obtaining a scale factor, while the rice seedling image was used for measuring actual stem-base width and plant height by employing the obtained scale factor. The results of automatic measurements resulted from different conditions were compared with those of manual measurements, accomplishing the assessment of measurement accuracy. Collectively, the smartphone application achieved R2 values of 0.9832 and 0.9796 in measuring stem-base width and plant height respectively, and corresponding RMSE values were 0.0307 mm and 1.2311 mm respectively, when tests were performed in various conditions including three camera resolutions, three photographing heights, and three sunlight conditions. The mean runtime for processing an individual image was about 1796.164 ms when a total of 350 rice seedlings were measured under various conditions. This work not only demonstrates that the smartphone application allows low-cost, fast, and accurate measurements of stem-base width and plant height in rice seedling, which can be used as a reasonable alternative to the traditional manual measurement method; but also offers a valuable reference for farmers or researchers in terms of evaluating in-field seedling growth quality, determining optimal seedling transplanting time, as well as guiding follow-up in-field fertilizer expenditures; and further provides methodological support for relevant researches in other crops or domains.

A Comparison of Four Different Methods of Prediction of Mesiodistal Widths of Unerupted Permanent Canines and Premolars

The success of orthodontic treatment depends upon the accurate assessment of mesiodistal widths of unerupted canines and premolars in mixed dentition stage. There are several methods available for mixed dentition analysis with dubious reliability in our population. Objective: To statistically develop new prediction equations for Pakistani subjects to predict the widths of unerupted upper canines and premolars (U345) and lower canine and premolars (L345) using mesiodistal widths of lower incisors (I1I2) and lower incisors and first molars (I1I2M1) and compare their performance with previously established methods of Moyers and Tanaka-Johnston. Methods: Study was conducted using the data from the dental casts of 200 Pakistani subjects with permanent teeth. Linear regression analysis was used to develop general and gender specific equations for estimation of U345 and L345 using the combined mesiodistal width I1I2 and I1I2M1. The actual and estimated sum of of U345 and L345 as determined by Moyers and Tanaka-Johnston and those from prediction equations based on I1I2 and I1I2M1 were compared using the paired sample t-test. Results: There were signficant differences in the actual mesiodistal widths of U345 and L345 and those calculated using Tanaka-Johnston and Moyers methods. Newly developed equations based on I1I2 and I1I2M1 performed better than the Moyers and Tanaka-Johnston methods in both the arches. Conclusion: Moyers and Tanaka-Johnston analyses generally overestimated U345 and L345 dimensions. The newly developed prediction equations based on I1I2 and I1I2M1 performed better for the prediction of mesiodistal widths of U345 and L345.

Slab Culvert Design as a Review

Abstract: Culverts are the monolithic structure made to pass across a roadway, railway lines etc. Soil strengthening is most to balance the flood water on both sides. It follows the traffic, water deigning, walking purpose, and any other activity is taken on culverts. The risk follow water level and up word and downward flooding is most important earth to reduce, water level reducing risk for the flooding. The structures to accomplish such water flow and traffic flow without any disturbance flow across the road are called culverts, small and major bridges depending on their span such as major span, lesser span it is totally depend on water flowing discharge. Culverts are commonly used both as cross drains for channel release and to pass water under a road at natural drainage and river crossings. Drains can be of changed forms such as circular arch, span, flat slab etc. Culverts can be built with different substantial material such as masonry, concrete, Bricks, stone or reinforced cement concrete. The structural elements are required to be designed to withstand to safety point and design structure and economical with all criteria are competed such as maximum bending moment and shear force. This research Paper provides full thoughts on the provisions in the Codes, design criteria, considerations and justification of all the above aspects on design. Culverts are required to be provided under earth embankment for crossing of water course like streams, Nallas across the embankment as road embankment cannot be allowed to obstruct the natural water way without any obstruction. The structural design involves consideration of load cases Slab empty, full, surcharge loads and design criteria are covered. And factors like live load, actual width, braking force, dispersal of load through fill, impact factor, co-efficient of earth compression etc. Applicable IRC Codes are compulsory to be mentioned in the examination and design of Slab ducts. The aim of this project is to analyse the Slab Culvert using STAAD PRO software. The structural basics of Slab Culvert are designed to resist maximum bending moment and shear force. The results obtained from STAAD in Research paper are almost similar to manual calculations as per the authors are suggested. The factor consideration cushion Depth, coefficient of earth pressure for lateral pressures on walls, width or angle of dispersion for live loads on Slab without cushion and with cushion for structural deformations are important items. The IS standard requirements in the design manual for roads and bridges (IRC-6-2000, IS 21- 2000) is used in the structural designing of concrete Slab Culverts. Keywords: culvert, types of culverts, IRC Condition, Software, Percent reinforcement, Pressure Cases, Side walls, Top slab.

Evaluation of soil wetting patterns in drip irrigation

Increasing agricultural water use efficiency is of prime importance owing to the decrease in availability of fresh water for agriculture. In these circumstances, drip irrigation is considered so far as the most efficient irrigation systems and can be utilized correctly with the knowledge of dimension of the soil wetted volume which is the main factors in determining the spacing of drippers. Therefore, the present study was conducted at the Instructional Farm, Faculty of Agricultural Engineering, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, Nadia, West Bengal during 2019–20 to examine the vertical (Z) and horizontal (W) water fronts advance within the soil profile at the dripper in a clay loam soil. Same volume of water (50 litre) was applied at the rate of 2.3 and 4.9 lph at each irrigation. By observing the soil on the tips of the auger, the depth of wetting was determined and noted down for different points on the line of the wetted area. It was found that there is little variation in the theoretical width and depth with the actual width and depth of wetting of the soil in case of 4.9 lph discharge rate. For the given discharge rate, the inaccuracy was less for the wetted depth than the wetted diameter. So, the information obtained from this investigation, about soil wetting pattern of drip irrigation system can be helpful to decide emitter, lateral spacing and system pressure for delivering required amount of water to the plant root zone. Thus, this investigation can be instrumental in design and management of drip system, which is slowly becoming a promising agricultural water management practice to tackle the huge food productivity problem and environmental issues of developing and under-developed countries.

Three-dimensional transient simulation of CO2 laser tissue vaporization and experimental evaluation with a hydrogel phantom

A quantitative analysis method of CO2 laser treatments promotes laser treatment performance and rapid clinical application of novel treatment devices. The in silico clinical trial approach, which is based on computational simulation of light-tissue interactions using the mathematical model, can provide quantitative data. Although several simulation methods of laser tissue vaporization with CO2 laser treatments have been proposed, validations of the CO2 laser wavelength have been insufficient. In this study, we demonstrated a tissue vaporization simulation using a CO2 laser and performed the experimental validation using a hydrogel phantom with constant physical parameters to evaluate the simulation accuracy of the vaporization process. The laser tissue vaporization simulation consists of the calculation of light transport, photothermal conversion, thermal diffusion, and phase change in the tissue. The vaporization width, depth, and area with CO2 laser irradiation to a tissue model were simulated. The simulated results differed from the actual vaporization width and depth by approximately 20% and 30%, respectively, because of the solubilization of the hydrogel phantom. Alternatively, the simulation vaporization area for all light irradiation parameters, which is related to the vaporization amount, agreed well with the actual vaporization values. These results suggest that the computational simulation can be used to evaluate the amount of tissue vaporization in the safety and effectiveness analysis of CO2 laser treatments.