Horizontal Vertical Ratio Research Articles

Horizontal–vertical ratio for concrete pumping pipe

For the construction of high-rise building, a horizontal pipe pumping test is usually conducted and using obtained test results, vertical actual constructing condition could be evaluated. In this study, horizontal and vertical pumping experiments are performed under various mixing and construction conditions using rheology-based quantitative performance prediction technology to derive a horizontal–vertical ratio of concrete pumping pipe for evaluating concrete pumping performance. Computational fluid dynamics is used to analyze the correlation between experimental results and additional vertical lengths. Analysis results confirm that compressive strength and plastic viscosity correlate with vertical and horizontal correlation coefficients; the pipe length, flow rate, and yield stress have no significant effect on the correlation coefficient. Based on analysis result considering various factors, multiple regression analysis is performed to propose horizontal–vertical ratio relationship for the concrete pumping pipe.

Water Invasion Law and Water Invasion Risk Identification Method for Deep Sea Bottom-Water Gas Reservoir

This study analyzes the water invasion characteristics and water encroachment of the deep sea bottom-water gas reservoir (LS17 field) in the South China Sea for the purpose of developing horizontal wells. Gas-producing profile tests and a three-dimensional (3D) water invasion simulation are used to produce a quantitative analysis of the bottom-water cresting influence factors. On this basis, we establish a suitable risk identification method for the water influx of a deep bottom-water reservoir. The results show that: (1) During the development of a bottom-water gas reservoir, the water ridging is affected by reservoir heterogeneity, production system and heel–toe effect of a horizontal wellbore, and reservoir heterogeneity is the main influencing factor; (2) the horizontal–vertical ratio of the well area determines whether the gas well productivity will be affected by the risk of water invasion. The stronger the reservoir heterogeneity, the smaller the safety limit value of the horizontal–vertical ratio; (3) when the permeability differential increases gradually, the safety limit value of the transverse longitudinal ratio decreases in turn; (4) based on the relationship curve between permeability level difference and the safety limit value of the horizontal–vertical ratio in the well area, the horizontal–vertical ratio of the N1H well is far greater than the safety limit value. The well is at high risk of water invasion and should be developed by water control. In order to improve deep seabed water and gas reservoirs, water control development should be carried out in well areas with sufficient water energy and high water invasion risk. The water invasion characteristics of bottom-water gas reservoirs under different water control technologies (such as variable density screen technology, filling water blocking, breathable coated gravel technology, etc.) and production systems (periodic gas production technology) should be studied. The research results can not only judge the water invasion risk of deep seabed water and gas reservoirs under different permeability levels and gas production rates but also provide a reference for water control development of offshore and onshore bottom-water and gas reservoirs.

Intelligent-based decision support system for diagnosing glaucoma in primary eyecare centers using eye tracker

It is quite alarming that the increase of glaucoma is due to the lack of awareness of the disease and the cost for glaucoma screening. The primary eye care centers need to include a comprehensive glaucoma screening and include machine learning models to elaborate it as decision support system. The proposed system considers the state of art of eye gaze features to understand cognitive processing, direction and restriction of visual field. There is no significant difference in global and local ratio and skewness value of fixation duration and saccade amplitude, which suggest that there is no difference in cognitive processing. The significance value of saccadic extent along vertical axis, Horizontal Vertical ratio (HV ratio), convex hull area and saccadic direction show that there is restriction in vertical visual field. The statistical measures (p < 0.05) and Spearman correlation coefficient with class label validate the results. The proposed system compared the performance of seven classifiers: Naïve Bayes classifier, linear and kernel Support Vector classifiers, decision tree classifier, Adaboost, random forest and eXtreme Gradient Boosting (XGBoost) classifier. The discrimination of eye gaze features of glaucoma and normal is efficiently done by XGBoost with accuracy 1.0. The decision support system is cost-effective and portable.

Novel multi-linear quantitative brain volume formula for manual radiological evaluation of brain atrophy

ObjectivesThe brain atrophy commonly occurs in elderly and in some childhood conditions making the techniques for quantifying brain volume needful. Since the automated quantitative methods of brain volume assessment have limited availability in developing countries, it was the purpose of this study to design and test an alternative formula that is applicable to all healthcare levels. MethodsThe multi-linear diagonal brain fraction formula (DBF) was designed from dimensions of brain relative to skull and ventricles. To test a developed formula, a total of 347 subjects aged between 0 and 18 years who had brain CT scans performed recruited and subjected to a systematic measurement of their brains in a diagonal brain fashion. ResultsOut of 347 patients evaluated, 62 subjects (17.8 %) were found to be cases of brain atrophy. The three radiological measurements which included sulcal width (SW), ventricular width (VW) and Evans Index (EI) were concurrently performed. SW and VW showed good age correlation. Similar tests were extended to diagonal brain fraction (DBF) and skull vertical horizontal ratio (VHR) in which DBF showed significant age correlation. ConclusionsThe DBF formula shows significant ability of differentiating changes of brain volume suggesting that it can be utilized as an alternative brain fraction quantification method bearing technical simplicity in assessing gross brain volume. Advances in knowledgeThe designed formula is unique in that it captures even the possible asymmetrical volume loss of brain through diagonal lines. The proposed scores being in term of ratios give four grades of brain atrophy.

Effects of droplet shape on impact force of low-speed droplets colliding with solid surface

Experimental studies of low-speed droplets colliding with a flat solid surface are performed to record the impact force and deformation by using a highly sensitive piezoelectric transducer and a high-speed camera. The experimental data are used to verify the accuracy of a 3D numerical model via the smoothed particle hydrodynamics method, and the numerical method is used to explore the effects of the droplet morphology on the collision force. As the horizontal–vertical ratio of the droplets increases, the peak impact force increases by a power function trend and the time to reach the collision force peak decreases. The relationship between the equivalent volume of a spherical droplet and the volume of an ellipsoid droplet with different horizontal–vertical ratios under the same peak impact force is obtained. Self-similar theory is also suitable for droplets with ellipsoid shape. Finally, the stresses inside the material after large-sized spherical and small-sized oblate droplets hit the wall surface are compared. Results indicate that the curvature radius of droplets is a key factor that affects initial impact force and material erosion.

DETERMINED SOIL CHARACTERISTIC OF PALU IN INDONESIA BY USING MICROTREMOR OBSERVATION

The Palu city, which is located in the active seismic zone of the Palu-Koro fault. Several powerful earthquakes have struck Palu city at previous years. One of the greatest earthquake event occurred in year 2006 which 6.2 Mw, about more a hundred buildings and houses were collapsed due to this earthquake. Palu-Koro fault also produced several tsunami events in year of 1927, 1968 and 1996. The latest earthquake struck Palu on 2012 (7.2 Mw) and it produced local tsunami. Since no soil profile map of Palu region available, we performed single observations of microtremors at 122 sites in Palu. Its results enabled us to estimate the site dependent amplification characteristics of earthquake ground-motion. We also conducted a 8-site microtremor array investigation to gain a representative determination of the soil condition of subsurface structures in Palu. From the dispersion curve of array observations, the central business district of Palu corresponds to relatively from soft soil to medium condition. Predominant periods due to horizontal vertical ratios (HVSRs) in Palu are in the range of 1.2 to 2.5 s

ESTIMATION OF SUBSURFACE STRUCTURE BASED ON MICROTREMOR, BORE HOLE OBSERVATIONS AND STOCHASTIC STRONG GROUND MOTION SIMULATIONS IN PALU CITY, CENTRAL SULAWESI, INDONESIA: A VALIDATION AND SENSITIVITY STUDY ON THE 23 JANUARY 2005 (PALU) EARTHQUAKE

In this study, we investigated the subsurface structure and strong ground motion parameters for Palu City. One of the major structures in Central Sulawesi is the Palu-Koro Fault system. Several powerful earthquakes have struck along the Palu-Koro Fault during recent years, one of the largest of which was an M 6.3 event that occurred on January 23, 2005 and caused several casualties. Following the event, we conducted a microtremor survey to estimate the shaking intensity distribution during the earthquake. From this survey we produced a map of the peak ground acceleration, velocity and ground shear strain in Palu City. We performed single observations of microtremors at 151 sites in Palu City. The results enabled us to estimate the site-dependent shaking characteristics of earthquake ground motion. We also conducted 8-site microtremor array investigation to gain a representative determination of the soil condition of subsurface structures in Palu. From the dispersion curve of array observations, the central business district of Palu corresponds to relatively soil condition with Vs ≤ 300 m/s, the predominant periods due to horizontal vertical ratios (HVSRs) are in the range of 0.4 to 1.8 s and the resonant frequency are in the range of 0.7 to 3.3 Hz. Three boreholes were throughout the basin especially in Palu area to evaluate the geotechnical properties of subsurface soil layers. The depths are varying from 1 m to 30 m. Strong ground motions of the Palu area were predicted based on the empirical stochastic green’s function method. Peak ground acceleration and peak ground velocity becomes more than 0.04 g and 30 kine in some areas, which causes severe damage for buildings in high probability. Keywords: Palu-Koro fault, microtremor, bore holes, peak ground acceleration and velocity.

Smoke detection based on condensed image

Smoke is difficult to detect whether based on static characteristic such as smoke color, texture, etc., or on dynamic characteristics such as frequency, shape or fluttering, etc. Smoke detection are always subject to some significant exceptions, e.g. swinging bags, driving cars in night, fog, and even moving persons. To efficiently detect smoke we condense video and find that smoke trajectories have some special characteristics, such as right-leaning line, smooth streamline, low-frequency, fixed source and vertical–horizontal ratio. Based on these characteristics it is very accurate and fast with little cost to find smoke even in a complex environment. To demonstrate the effectiveness, the proposed method is conducted on various videos, e. g. videos shot by ourselves, videos from Korea CVPR Lab, videos from YouTube, videos from Bilkent University. Experiments show that similar objects often mistaken by other algorithms are differentiated rightly and the ratio of correct detection is promoted to a higher level of 83.0%.

Estimation of S-Wave Velocity Profiles and Site Amplification Around the K-NET Tsukidate Station, Miyagi Prefecture, with Reference to Large PGA During the 2011 off Pacific Coast of Tohoku Earthquake, Japan

In this study we investigated site amplifications in shallow soil around Tsukidate station (MYG004) of KNET in Miyagi prefecture with a seismic intensity of 7 during the 2011 off the Pacific Coast of Tohoku Earthquake from aftershock observation and microtremor explorations. We conducted aftershock observations by installing 8 temporary stations. We estimated site amplifications of S-wave from the observed data. We found that the predominant period of amplification at a site near MYG004 was 0.2 seconds. The amplification factor at a site on cut ground with a distance of 20 m from MYG004 was significantly different. Furthermore, the amplifications were also different with changing predominant periods from 0.1 to 0.5 seconds in an area of 1 km from MYG004. Shallow Swave velocity profiles were deduced from microtremor array explorations at the stations. Results indicated that shallow low-velocity layers with a thickness of less than 30 meters are responsible for variation of the amplifications. Predominant periods in calculated 1D amplifications were similar to those observed in the aftershock observations. The observed amplification factor at the site nearMYG004, however, was two times larger than the calculated one, suggesting the inappropriateness of the 1D assumption at the site possibly due to the effects of a cliff near MYG004. We also found from horizontal-vertical ratios of microtremors that the site effects on the cliff were also different at frequency higher than 10 Hz within 30 meters around MYG004. This also suggests lateral variation in the site effects at the high frequency near MYG004.

Estimation of Earthquake Ground Motion in Padang, Indonesia

Several powerful earthquakes have struck Padang during recent years, one of the largest of which was an M 7.6 event that occurred on September 30, 2009 and caused more than 1000 casualties. Following the event, we conducted a questionnaire survey to estimate the shaking intensity distribution during the earthquake. About 500 residents of Padang were interviewed. The residents received explanations for each item on the questionnaire from the interviewers, and answers were filled in directly on the answer sheets. From this survey we produced a map of the shaking intensity distribution in Padang. In addition to the questionnaire survey, we performed single observations of microtremors at 110 sites in Padang. The results enabled us to estimate the site-dependent amplification characteristics of earthquake ground-motion. We also conducted a 12-site microtremor array investigation to gain a representative determination of the soil condition of subsurface structures in Padang. From the dispersion curve of array observations, the central business district of Padang corresponds to relatively soft soil condition with Vs30 less than 400 m/s, the predominant periods due to horizontal vertical ratios (HVSRs) are in the range of 2.0 to 4.0 s, and the seismic intensity obtained is upper 5 (5+) in the JMAi scale. By making these observations, we can obtain a relationship between soil types, predominant periods and seismic intensities.