Equal Height Research Articles

Shake table tests on story-to-story pounding between adjacent RC buildings

Pounding between adjacent buildings and their devastating effects have been frequently reported during numerous major earthquakes. Although poundings exhibit more destructive effects on RC buildings compared to steel buildings, the majority of previous experimental studies have mainly concentrated on steel specimens. Furthermore, there has been a notable scarcity of extensive large-scale experimental studies on this subject. Therefore, the primary objective of this study is to experimentally determine the effects of different types of pounding on the seismic responses of RC buildings. To this aim, three half-scaled two-story RC specimens were constructed and were tested. In the tests, three cases were considered: (i) without pounding, (ii) pounding between taller and shorter buildings (slab-to-slab interaction at one floor), and (iii) pounding between buildings with equal heights (slab-to-slab interaction at the two floors). The experimental results showed that pounding and its types played a critical role in structural responses such as floor accelerations, displacements, hysteretic responses, and dynamic characteristics. Additionally, each pounding type led to different damage mechanisms in the specimens.

An Enhanced LBPH Algorithm for Robust Face Feature Extraction

From security systems to human-computer interaction, face recognition technology is a key component in many different applications. In this domain, the local binary pattern histogram (lbph) algorithm has shown great promise due to its ability in texture-based feature extraction and robustness. In this study, the performance of lbph algorithm is improved by optimising important parameters: radius, number of neighbours and grid configuration. Tweaking these parameters systematically enable us to get the most success out of this algorithm. Lbph algorithm parameters has been tuned into a 5x7 dimensional matrix, which gives us total of 35 grids with equal width and height pixels. In other words, one central pixel plus 34 neighbouring pixels where the radii of 3 square neighbourhoods can be adjusted. The study combines the experimental exploration with fine-tuning via machine learning approaches to optimize lbph algorithm. Finally, we have provided experimental results on intra-class and inter-class feature distribution analysis conducted on selected images taken under constraints and unconstraint environments. The performance of our novel 34N-LBPH algorithm showed very low values by obtaining intra-class average means of 0.031, 0.078, and 0.101 for three classes under constraint environment indicating the proposed 34n-lbph is robust for facial feature extraction. The findings suggest that our enhanced algorithm, 34 neighbour linear binary pattern Histogram (34N-LBPH) can effectively handle variations in lighting, expressions and occlusions, contributing to the advancement of facial feature extraction for face recognition.

SA-SatMVS: Slope Feature-Aware and Across-Scale Information Integration for Large-Scale Earth Terrain Multi-View Stereo

Satellite multi-view stereo (MVS) is a fundamental task in large-scale Earth surface reconstruction. Recently, learning-based multi-view stereo methods have shown promising results in this field. However, these methods are mainly developed by transferring the general learning-based MVS framework to satellite imagery, which lacks consideration of the specific terrain features of the Earth’s surface and results in inadequate accuracy. In addition, mainstream learning-based methods mainly use equal height interval partition, which insufficiently utilizes the height hypothesis surface, resulting in inaccurate height estimation. To address these challenges, we propose an end-to-end terrain feature-aware height estimation network named SA-SatMVS for large-scale Earth surface multi-view stereo, which integrates information across different scales. Firstly, we transform the Sobel operator into slope feature-aware kernels to extract terrain features, and a dual encoder–decoder architecture with residual blocks is applied to incorporate slope information and geometric structural characteristics to guide the reconstruction process. Secondly, we introduce a pixel-wise unequal interval partition method using a Laplacian distribution based on the probability volume obtained from other scales, resulting in more accurate height hypotheses for height estimation. Thirdly, we apply an adaptive spatial feature extraction network to search for the optimal fusion method for feature maps at different scales. Extensive experiments on the WHU-TLC dataset also demonstrate that our proposed model achieves the best MAE metric of 1.875 and an RMSE metric of 3.785, which constitutes a state-of-the-art performance.

Numerical simulations of the interactions between counterflowing density currents

The collision and interactions between counterflowing density currents frequently occur in nature and engineering practices along the coastal regions. However, the mechanisms and implications of these interactions remain an active research area. In this study, we developed a high-resolution numerical model to simulate the hydrodynamic characteristics of symmetric and asymmetric colliding saline density currents. The aim was to understand the interaction mechanisms, quantify collision parameters, and provide baseline physical insights into the implications of such interactions. The direct numerical simulations reveal that when equal height counterflowing saline density currents collide, the dynamic characteristics of the resulting flow depend on the density difference between the colliding currents, collaborating experimental results. The interaction process initiated mixing and significant vertical motion in the resulting mixed fluid, which attained a maximum rise height of approximately twice that of the colliding currents, thereby enhancing the vertical motion of hypersaline fluid in the ambient column. While the extent of mixing at the collision boundary increases with increasing asymmetry between the colliding currents, a relationship is observed between the buoyancy ratio of the colliding currents and the maximum rise height of the vertically displaced fluid. Given that desalination operations require effective dispersion of brine into the marine environment to minimize local impacts, understanding the collision dynamics of counterflowing saline currents would facilitate improved engineering design and implementation of environmentally compliant coastal management strategies.

UG secondary development of path generation of straight profile toroidal worm finishing tool

Abstract Due to the complexity of the right and left tooth surfaces of the straight profile toroidal worm, it is difficult in 3D modeling and NC programming. Based on the equal residual height algorithm, this paper deduces the calculation formula of the cutter contact and cutter point of the tooth surface of the straight profile toroidal worm by using the round nose milling cutter, calculates the cutter point coordinates and rotation angles of each point of the tooth surface of the straight profile toroidal worm through the UG secondary development interface and Visual Studio software, and generates the numerical control code on this basis. The machining simulation and experiment show that the machining efficiency and error of the straight profile torus worm machined by the tool path prepared by the equal residual height method are better than that of the isoparametric method.

Simulation study on the dynamic characteristics of natural circulation coupled phase change material for equal height difference passive containment cooling system

The passive containment cooling system (PCCS) plays a significant role in ensuring the safety of nuclear power plants. To further reduce peak pressure in the containment during a loss of coolant accident (LOCA), phase change materials (PCMs) are utilized to improve the system’s cooling effectiveness. The dynamic simulation model of PCCS has been developed using Apros software. This article focuses on examining the system’s dynamic characteristics related to various tube startup methods and comparatively analyzing the impact of different PCM thicknesses on heat transfer capacity. The results indicate that post-accident, PCM significantly suppresses peak pressure in the containment. Under the full tube startup method with 4 mm PCM, the peak pressure decreases to 1.75 MPa, whereas under the empty tube startup method, it is reduced to 1.69 MPa. With natural circulation empty tube startup method, PCM can reduce pressure change intensity in the containment but negatively affects natural circulation heat transfer. Although the full tube startup method underperforms the empty tube startup method on suppressing peak pressure, PCM can positively affect natural circulation heat transfer in the early stages of the accident. Empty tube startup offers the advantages of higher heat transfer capacity and lighter weight, making it the optimal choice for ocean nuclear platforms. Additionally, the higher peak power of PCM heat transfer under the empty tube startup method indicates that system can withstand larger thermal shocks.

Chasing the objective upper eyelid symmetry formula; R2, RMSE, POC, MAE, and MSE.

Investigate the most appropriate mathematical formula to objectively express upper eyelid contour symmetry. 62 eyes of 31 patients were included in the study. The upper eyelid contour symmetry of the patients was classified subjectively (independent of MRD1) as poor, acceptable, and good by three oculoplastic specialists (senior, expert, and junior surgeon). Bézier curves of the upper lid contour were drawn with ImageJ software (NIH, Bethesda, MA, USA). Using the algorithms created by Author SKC in Spyder (Python 3.7.9.), the symmetry of the Bézier curves of the left eyelids were obtained according to the y-axis, and the mid-pupils of both eyes were superimposed. The lower curve moved vertically to the equal height of the other curve to equalize MRD1's. R2 (Coefficient of determination), RMSE (Root-mean-square error), MSE (Mean squared error), POC (Percentage of co-efficiency), and MAE (Mean absolute error) were calculated. We evaluated the correlation between these objective formulas and the subjective grading of three surgeons using Spearman's rho (ρ). The correlation coefficient of RMSE and MSE were the same for all surgeons grading. There was a strong correlation between the senior surgeon's subjective scoring (N; poor = 8, acceptable = 16, good = 8) and R2, RMSE, POC, MAE (ρ = 0.643, p < 0.001, ρ = -0.607, p < 0.001, ρ = 0.562, p < 0.001, ρ = -0.517, p < 0.001, respectively). We found a strong relationship between the expert surgeon's subjective scoring (N; poor = 9, acceptable = 13, good:10) and R2 (ρ = 0.611, p < 0.001), RMSE (ρ = -0.549, p < 0.001), POC (ρ = 0.511, p < 0.001), and MAE (ρ = -0.450, p < 0.05). We found a strong correlation between junior surgeon's subjective scoring (N; poor = 6, acceptable = 18, good = 8) and R2, RMSE, and POC (ρ: -0.517, p < 0.001; ρ: -0.470, p < 0.001; ρ: 0.521, p < 0.001; respectively) and moderate correlation between MAE (ρ:-0.394, p < 0.05). The highest correlation is observed with R2. RMSE, MSE, POC, MAE, and especially R2, may quantitatively express upper eyelid contour symmetry, comparable with the oculoplastic surgeon. The highest correlation was observed between the senior surgeon and R2, and decreases with the experience of the surgeon.

A design of tuned mass damper with piezoelectric stack energy harvester and two-stage force amplification frame

The paper deals with a novel tuned mass damper (TMD) with an energy harvester consisting of a combination of piezo stacks and two-stage force amplification frames connected in series with TMD springs (TMD-2sPSFAFs). The governing equations of 2sPSFAF are established first, followed by those of TMD-2sPSFAF. It will be demonstrated that the reduced order model of the series combination of 2sPSFAF and TMD spring is an equivalent piezo stack energy harvester. Using the optimal results according to the fixed point theory, the conditions for selecting stiffnesses of piezo stacks and TMD spring are obtained. Next, a numerical examination of the electromechanical system reveals that the voltage amplitude curve has a fixed point independent of TMD spring stiffness. Furthermore, an effective stiffness of the TMD spring would be found to ensure that the peaks of mechanical magnification and voltage amplitude curves are of equal heights.

Drought tolerance improvement for grain yield of a modern rice variety based on morphological and physiological response

Growth of rice (Oryza sativa L.) is severely affected by drought stress, which leads to decreased rice production in rainfed ecosystems worldwide. Particularly, modern rice varieties are more susceptible to drought stress rather than traditional rice varieties. In the present study, a modern short-term rice variety, ADT37, abundantly cultivated in the Cauvery delta region of the southern part of India, was improved for grain yield by introducing qDTY1.1 through the conventional backcross method. Positive F1 progenies were identified using RM431 linked with qDTY1.1 in PCR amplification. In phenotypic selection, rice progenies with suitable plant height to avoid linkage drag as well as high degree of drought tolerance to manage the drought stress were selected and advanced through the backcrossing process up to the BC3 generation. Finally, two near isogenic lines with equal plant height to the recurrent parent and high degree of drought tolerance were selected. A positive effect of qDTY1.1 on plant height and fertile seeds was revealed. In the future, the selected superior near isogenic lines would be useful to rice researchers and farmers facing unexpected water crises. Moreover, the morphological marker associated with the performance of crops according to the intensity of stress will support climate resilient agriculture.

Morphology combined with HER2 D-DISH ploidy analysis to diagnose partial hydatidiform mole: an evaluation audit using molecular genotyping

AimsA hydatidiform mole (HM) is classified as complete (CHM) or partial (PHM) based on its morphology and genomic composition. Ancillary techniques are often required to confirm a morphologically suspected PHM...

Effects of Stepdown Pressure and Wettability on Bubble Nucleation in Gas-Supersaturated Oil-Water Systems

Summary This study investigates the influences of wettability and stepdown pressure on pressure-driven bubble nucleation within a gas-supersaturated oil-water system. Two gases—carbon dioxide (CO2), which is highly soluble in water, and methane (CH4), which is sparingly soluble in water—were used individually for the bubble nucleation experiments. Equal heights of oil (n-decane) and water, in a wettability-controlled glass vial placed in a saturation cell, were saturated with either of the gases at 6000-mbar pressure, followed by applying a stepdown pressure of either 6000 mbar, 500 mbar, or 100 mbar to start the bubble nucleation process. The average bubble nucleation pressures for CO2 and CH4 gases on a hydrophobic vial surface with 500-mbar stepdown pressure were 4333 ± 289 mbar and 3833 ± 289 mbar, respectively. It is important to note that the bubble nucleation took place exclusively on the portion of the solid surface submerged in water. However, bubble nucleation did not take place with 100-mbar stepdown pressure for either gas in the hydrophobic vial despite the pressure being brought down to atmospheric pressure. As expected, bubble nucleation did not take place in the hydrophilic vial for the gases despite the pressure being brought down to atmospheric pressure from the saturation pressure, regardless of the stepdown pressure. In addition, bubble nucleation did not take place in CO2-supersaturated water in the oil-wetted hydrophilic and hydrophobic vials, even at maximum supersaturation.

The impact of sward height, forage quality and competitive conditions on foraging behaviour of free-ranging rabbits (Oryctolagus cuniculus L.)

The habitat choice of the small hindgut fermenter, the European rabbit (Oryctolagus cuniculus L.), was studied in relation to sward height, forage quality, population size fluctuations and spatial distribution of burrows in a temperate grassland. In a multi-phase differential clipping experiment with alternating short and tall vegetation strips, rabbits tended to graze near the closest burrows in situations of equal vegetation heights, while a clear preference for short swards was found during summer (July). In this period, general crude protein content was significantly lower than in spring (April) and autumn (September), apparently leading to a potential forage quality deficit. The summer behavioural pattern with short sward preference coincided with the relatively higher crude protein content of short swards as compared to tall swards in this period, and with higher intraspecific competition, due to significantly larger numbers of animals present in summer. In autumn, rabbit densities decreased, while crude protein content of both short and tall vegetation increased to a higher, though not significantly different level, comparable with spring crude protein content. In those conditions, significant preference for low vegetation height could no longer be detected. Data suggest that selection for nutritive quality appears when intraspecific competition is high and nutritive quality remains under a certain threshold value. When, in autumn, competition decreases and nutritive quality increases again, short sward preference disappears. We conclude that short sward preference is primarily caused by the better forage quality of re-growth in periods of forage quality limitation, while this preference disappears when forage quality limitation no longer occurs.

Design of a multi-scale cylindrical porous fin based on constructal theory

Porous fin (PF) has obvious advantages in heat dissipation, so it is necessary to analyze and optimize its performance. In this paper, a multi-scale cylindrical porous fin (PF) model is built. Firstly, the fin length and height ratio are chosen as the optimization variables, constructal design is conducted with the objective of complex function (CF) composed of maximum temperature difference (MTD) and pumping power consumption (PPC). Then, an artificial neural network (ANN) model is established by using data samples, and multi-objective optimization (MOO) is performed using the NSGA-II method. The findings indicated that the optimal length and height ratio of the fin are 4.763 mm and 1.017 under the conditions that the total PF envelope volume and PF-material volume are fixed. The CF is reduced by 51.0% compared with that before optimization. The multi-scale cylindrical porous fin with different heights is superior to the single-scale one with equal height. For MOO, the lowest deviation index obtained by TOPSIS or LINMAP decision-making strategy (DMS) is 0.258. For this case, the MTD is reduced by 81.9%, and the PPC is reduced by 18.7%. Therefore, the relevant optimal structure herein can be used as the optimal design solution for the multi-scale cylindrical porous fin.

Farklı Zemin Sınıfına Göre Elde Edilmiş Düşey Elastik Tasarım Spektrumlarının Yapı Davranışına Etkisi ve K.Maraş Deprem Verileri ile Karşılaştırılması

In practice and theory, many types of reinforced concrete slabs are used, such as beamed, beamless, and ribbed slabs. Beamed floors are connected to the columns by means of beams, and their vertical and horizontal loads are transferred to the columns through these beams. Therefore, beams are accepted as an important structural element by earthquake experts and many formulas and approaches have been developed in terms of horizontal and vertical load effects that occur in order to transfer the load transfer to the elements as desired. In this study, beam shear forces that occur under the influence of vertical earthquakes at the i and j ends of the beams of a fictional building whose floors are modeled according to the rigid diaphragm assumption in the ETABS were investigated. In this study, the shear forces that occur in the beams of a fictionally designed building under the effect of vertical earthquakes, and the floors carried by the beams are examined by designing with the assumption of a rigid diaphragm. The structure is designed with 3 openings in the X and Y directions and each opening is equal and 5 m. The 5-storey building has been designed to have equal floor heights of 3 m. The structure was obtained by using parameters belonging to 5 different soil classes as ZA, ZB, ZC, ZD, ZE, and 5 different vertical elastic design spectrums represented by the abbreviations EZ_ZA, EZ_ZB, EZ_ZC, EZ_ZD were activated in the ETABS. Seismic station coordinates numbered 4631 in K.Maras/Elbistan were used to obtain the parameters to be used in obtaining the vertical elastic design spectral of the structure. These coordinates were selected in order to compare the i and j end shear forces of the beam with the previously obtained beam i and j ends shear forces by influencing the Mw:7.6 Elbistan earthquake recorded by the seismic station to the building. Since the structure is symmetrical in both X and Y directions, the results obtained from beams B2, B3, B5, B19 represent the beam shear forces occurring at the i and j ends of all beams of the structure. As a result, it has been seen that the highest values of beam i and j end shear forces, obtained by affecting both the vertical elastic design spectral and the data of the vertical component of the Elbistan Mw:7.6 earthquake, were obtained on the 5th floor, which is the top floor of the building. The structure showed similar behavior among the different vertical elastic design spectral, and the highest value was obtained for each vertical elastic design spectrum at the 5th floor. Among these vertical elastic design spectral, the EZ_ZC spectrum gave the highest value at the 5th floor of the building. When the EZ_ZC vertical elastic design spectrum beam i and j end shear forces are compared with the beam i and j end shear forces of the vertical component data of the Elbistan Mw:7.6 earthquake, it is seen that the difference is not significant. It has been seen that the beam i and j end shear force value of the spectrum is higher than the shear force value.

Optimization of PCM layer height of cascaded two-layered packed-bed thermal energy storage tank with capsules of varying diameters based on genetic algorithm

The packed-bed thermal energy storage (PBTES) technology exhibits significant potential for utilization in various energy sectors, including concentrating solar power, city heating systems and power peaking. This paper uses a genetic algorithm (GA) to optimize the phase change material (PCM) layer height arrangement of cascaded two-layered PBTES with capsules of varying diameters to enhance thermal performance during charging. The optimization process considers the oscillatory distribution of radial porosity, and the objective function utilized for assessing the thermal performance of the system is thermal energy storage (TES) rate density. The TES rate density for over 2000 different layer height arrangements was calculated. The findings indicate that the PCM layer height significantly influences the thermal performance of the tank in each layer. The charging performance is optimal when the layer height ratio of high and low melting point PCM is 12.05 % and 87.95 %, respectively, which is the optimal model. In comparison to the original model with equal bed height, the optimal model demonstrates a reduction in charging time of 28 %, increases the TES rate density by 17.68 %, and the greatest improvement in charging efficiency reached 31.28 %. And reduces the unit TES cost by 13 %. This study shows that GA is an effective tool for optimizing the structural arrangement of PBTES.

A catenary-like cable confined in a circular cylinder

The problem of obtaining the curve of a cable suspended between two points, supporting only its own weight, was solved simultaneously, in the 17th century, by Johann Bernoulli, Leibniz, and Huygens. This curve is called the catenary. This article solves a modified problem in which the suspended cable is confined in a vertical cylinder. For this, an functional is formulated to describe the potential energy of a fixed-length confined cable in any possible arrangement. Then, the variational problem of extremizing this functional is presented and the Euler-Lagrange differential equation is deduced. The analytical solution of this equation is obtained for the cable suspended by two points at equal and different heights. Furthermore, the tensile force acting on the cable is determined. Numerical results are presented comparing the effect of confinement on the tensile force in relation to the traditional catenary.

Heat transfer characteristics of passive containment cooling system with equal height difference under steady-state conditions

In the nuclear energy utilization, the passive containment cooling system (PCCS) holds paramount importance, with its heat transfer performance standing as a critical aspect of nuclear safety. This study simulated the flow and heat transfer behaviors of PCCS with equal height difference by APROS software under a broad range of steady state operating conditions. At first, the flow pattern of natural circulation is categorized by phase state of flow through operational parameters. A criterion model of boundary of phase change is proposed with prediction deviation of less than ±25 %. Furthermore, the influence of various operation parameters such as temperature, non-condensable gas content, and pressure on the heat transfer behaviors of natural circulation was also revealed. A new heat transfer coefficient correlation for both single-phase and two-phase conditions is proposed with prediction deviation of ±15 %. Finally, the thermal stratification phenomenon in the containment vessel with non-condensable gas was investigated, indicating that local heat transfer characteristics in the upper region surpass those in the lower section on account of deposition of the non-condensable gas at bottom of the vessel.

Probabilistic investigation of the pounding effect in steel moment resisting frames with equal and unequal heights

In this research, the influence of the pounding phenomenon of two adjacent steel moment resisting frames (SMRFs) with 2 and 5-story with an intermediate ductility is investigated by considering equal and unequal heights under seismic excitations. In this way, two scenarios are applied. The first and second scenarios are related to the pounding of two SMRFs with an equal height (both frames with 2-story) and an unequal height (2-story and 5-story frames), respectively. In the following, at first, sensitivity analysis is conducted by the Monte Carlo simulation (MCS) method. Then, the collapse performance of the studied SMRFs is evaluated by incremental dynamic analysis (IDA), and fragility curves under 14 far-fault records and also, the failure probability is predicted by the Kriging meta-model. The results of sensitivity analysis indicate that the yield strength of cross-sections and dead load were the greatest effect on failure probability computation. Also, in the statistical level of 50%, the collapse probability of SMRFs with an equal height is 17% compared to the SMRFs with an unequal height. Also, the results of the Kriging meta-model show that the failure probability is increased by 65% in an unequal height versus an equal height.

Fast scaled cylindrical holography based on scaled convolution

Recently, the 360°display of cylindrical holography has garnered significant attention. However, existing studies have been limited to concentric cylindrical surfaces with equal heights, which restricts the height of the objects. In this paper, a fast scaled cylindrical holography is proposed based on scaled convolution to break this constraint. Firstly, the scale cylindrical diffraction is derived using the Rayleigh–Sommerfeld diffraction formula for scaled cylindrical holography, in which the object’s height can be adjusted. Then, a method of fast scaled cylindrical diffraction is presented by scaled convolution based on scaled Fourier Transform, and it significantly reduces computational time, enhancing its practical feasibility. Furthermore, the proposed method is extended to 3D objects using a layer-oriented approach. Moreover, the effectiveness and feasibility of the proposed method are verified through numerical simulations and optical experiments. Therefore, the issue of the constraint on the object’s height in cylindrical holography is thoroughly discussed and effectively addressed for the first time. This breakthrough paves the way for the development of a zoom-able cylindrical holographic display with immense potential for applications in mixed reality and beyond.

A Fast Method for Robust Video Watermarking Based on Zernike Moments

Watermarking by Zernike moments has been proven to be effective in providing high rotational resistance. However, due to the high computational complexity, the conventional video watermarking methods using Zernike moments are developed for videos with low resolution. Moreover, according to the properties of Zernike moments, only the matrices of equal height and width can be calculated since the inscribed circle of the original image matrix is selected as the area to be processed, but most of the available videos on the Internet do not meet such requirement. To solve the above problem, this paper proposes a fast watermarking method based on Zernike moments for high resolution videos to resist various attacks. In the proposed method, the frames of a video sequence are firstly grouped, from which a certain number of frame pairs are then selected for watermark embedding. For each frame pair to be embedded, we partition one frame into a set of disjoint blocks and apply singular value decomposition to each block to obtain a square feature matrix. Thereafter, by calculating all the Zernike moments, secret information is embedded into the selected Zernike moments to achieve superior robustness while keeping imperceptibility. Finally, according to the video encoding framework, we overwrite the frame difference of the frame pair by the watermark to resist compression and transcoding attacks. Furthermore, we propose two optional methods for compensating the special cases of rotation and scaling attacks during watermark detection. Experiments demonstrate the advantage of our method over the existing robust watermarking methods.