Search results for: ground stabilization
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2385

Search results for: ground stabilization

1275 Spatial Distribution and Habitat Preference of Indian Pangolin (Manis crassicaudata) in Madhesh Province, Nepal

Authors: Asmit Neupane, Narayan Prasad Gautam, Prabin Bhusal

Abstract:

Indian pangolin, locally called as ‘Salak’, ‘Sal machha’, ‘Pakho machha’, is a globally endangered species, nationally categorized as a critically endangered species, protected under the National Parks and Wildlife Conservation (NPWC) Act 1973 and appended in Appendix I of CITES. Indian pangolins occur in the tropical areas of Terai region and Chure foothills of eastern Nepal, and India, Bangladesh, Pakistan, and Sri Lanka. They utilize a wide range of habitats, including primary and secondary tropical forest, limestone forest, bamboo forest, grassland, and agricultural lands. So, in regard to this fact, this research is aimed to provide detailed information regarding the current distribution pattern, status, habitat preference, prevailing threats and attitude of local people towards species conservation in Madhesh Province, Nepal. The study was conducted in four CFs, two from Bara district and two from Dhanusha district. The study area comprised of Churia range and foothills with tropical and sub-tropical vegetation. A total of 24 transects were established, each of 500*50 m2, where indirect signs of Indian pangolin, including active/old burrows, pugmarks and scratches, were found. Altogether 93 burrows were found, where only 20 were active burrows. Similarly, a vegetation survey and social survey was also conducted. The data was analyzed using Stata 16 and SPSS software. Distance from settlement, ground cover, aspect, presence/absence of ants/termites and human disturbance were the important habitat parameters having statistically significant relationship with the distribution of Indian pangolin in the area. The species was found to prefer an elevation of 360 to 540m, 0-15º slope, red soil, North-east aspect, moderate crown and ground cover, without fire and rocks, vicinity of water, roads, settlement, Sal dominated forest and minimum disturbed by human activities. Similarly, the attitude of local people towards Indian pangolin conservation was found to be significantly different with respect to age, sex and education level. The study concludes that majority of active burrows were found in Churia hills, which indicates that Indian pangolin population is gradually moving uphill towards higher elevation as hilly area supports better prey availability and also less human disturbance. Further studies are required to investigate microhabitat preferences, seasonal variability and impacts of climate change on the distribution, habitat and prey availability of Indian pangolin for the sustainable conservation of this species.

Keywords: conservation, IUCN red list, local participation, small mammal, status, threats

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1274 Influence of Surface Fault Rupture on Dynamic Behavior of Cantilever Retaining Wall: A Numerical Study

Authors: Partha Sarathi Nayek, Abhiparna Dasgupta, Maheshreddy Gade

Abstract:

Earth retaining structure plays a vital role in stabilizing unstable road cuts and slopes in the mountainous region. The retaining structures located in seismically active regions like the Himalayas may experience moderate to severe earthquakes. An earthquake produces two kinds of ground motion: permanent quasi-static displacement (fault rapture) on the fault rupture plane and transient vibration, traveling a long distance. There has been extensive research work to understand the dynamic behavior of retaining structures subjected to transient ground motions. However, understanding the effect caused by fault rapture phenomena on retaining structures is limited. The presence of shallow crustal active faults and natural slopes in the Himalayan region further highlights the need to study the response of retaining structures subjected to fault rupture phenomena. In this paper, an attempt has been made to understand the dynamic response of the cantilever retaining wall subjected to surface fault rupture. For this purpose, a 2D finite element model consists of a retaining wall, backfill and foundation have been developed using Abaqus 6.14 software. The backfill and foundation material are modeled as per the Mohr-Coulomb failure criterion, and the wall is modeled as linear elastic. In this present study, the interaction between backfill and wall is modeled as ‘surface-surface contact.’ The entire simulation process is divided into three steps, i.e., the initial step, gravity load step, fault rupture step. The interaction property between wall and soil and fixed boundary condition to all the boundary elements are applied in the initial step. In the next step, gravity load is applied, and the boundary elements are allowed to move in the vertical direction to incorporate the settlement of soil due to the gravity load. In the final step, surface fault rupture has been applied to the wall-backfill system. For this purpose, the foundation is divided into two blocks, namely, the hanging wall block and the footwall block. A finite fault rupture displacement is applied to the hanging wall part while the footwall bottom boundary is kept as fixed. Initially, a numerical analysis is performed considering the reverse fault mechanism with a dip angle of 45°. The simulated result is presented in terms of contour maps of permanent displacements of the wall-backfill system. These maps highlighted that surface fault rupture can induce permanent displacement in both horizontal and vertical directions, which can significantly influence the dynamic behavior of the wall-backfill system. Further, the influence of fault mechanism, dip angle, and surface fault rupture position is also investigated in this work.

Keywords: surface fault rupture, retaining wall, dynamic response, finite element analysis

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1273 Influence of Cryo-Grinding on Particle Size Distribution of Proso Millet Bran Fraction

Authors: Maja Benkovic, Dubravka Novotni, Bojana Voucko, Duska Curic, Damir Jezek, Nikolina Cukelj

Abstract:

Cryo-grinding is an ultra-fine grinding method used in the pharmaceutical industry, production of herbs and spices and in the production and handling of cereals, due to its ability to produce powders with small particle sizes which maintain their favorable bioactive profile. The aim of this study was to determine the particle size distributions of the proso millet (Panicum miliaceum) bran fraction grinded at cryogenic temperature (using liquid nitrogen (LN₂) cooling, T = - 196 °C), in comparison to non-cooled grinding. Proso millet bran is primarily used as an animal feed, but has a potential in food applications, either as a substrate for extraction of bioactive compounds or raw material in the bakery industry. For both applications finer particle sizes of the bran could be beneficial. Thus, millet bran was ground for 2, 4, 8 and 12 minutes using the ball mill (CryoMill, Retsch GmbH, Haan, Germany) at three grinding modes: (I) without cooling, (II) at cryo-temperature, and (III) at cryo-temperature with included 1 minute of intermediate cryo-cooling step after every 2 minutes of grinding, which is usually applied when samples require longer grinding times. The sample was placed in a 50 mL stainless steel jar containing one grinding ball (Ø 25 mm). The oscillation frequency in all three modes was 30 Hz. Particle size distributions of the bran were determined by a laser diffraction particle sizing method (Mastersizer 2000) using the Scirocco 2000 dry dispersion unit (Malvern Instruments, Malvern, UK). Three main effects of the grinding set-up were visible from the results. Firstly, grinding time at all three modes had a significant effect on all particle size parameters: d(0.1), d(0.5), d(0.9), D[3,2], D[4,3], span and specific surface area. Longer grinding times resulted in lower values of the above-listed parameters, e.g. the averaged d(0.5) of the sample (229.57±1.46 µm) dropped to 51.29±1.28 µm after 2 minutes grinding without LN₂, and additionally to 43.00±1.33 µm after 4 minutes of grinding without LN₂. The only exception was the sample ground for 12 minutes without cooling, where an increase in particle diameters occurred (d(0.5)=62.85±2.20 µm), probably due to particles adhering to one another and forming larger particle clusters. Secondly, samples with LN₂ cooling exhibited lower diameters in comparison to non-cooled. For example, after 8 minutes of non-cooled grinding d(0.5)=46.97±1.05 µm was achieved, while the LN₂ cooling enabled collection of particles with average sizes of d(0.5)=18.57±0.18 µm. Thirdly, the application of intermediate cryo-cooling step resulted in similar particle diameters (d(0.5)=15.83±0.36 µm, 12 min of grinding) as cryo-milling without this step (d(0.5)=16.33±2.09 µm, 12 min of grinding). This indicates that intermediate cooling is not necessary for the current application, which consequently reduces the consumption of LN₂. These results point out the potential beneficial effects of millet bran grinding at cryo-temperatures. Further research will show if the lower particle size achieved in comparison to non-cooled grinding could result in increased bioavailability of bioactive compounds, as well as protein digestibility and solubility of dietary fibers of the proso millet bran fraction.

Keywords: ball mill, cryo-milling, particle size distribution, proso millet (Panicum miliaceum) bran

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1272 Application of Response Surface Methodology (RSM) for Optimization of Fluoride Removal by Using Banana Peel

Authors: Pallavi N., Gayatri Jadhav

Abstract:

Good quality water is of prime importance for a healthy living. Fluoride is one such mineral present in water which causes many health problems in humans and specially children. Fluoride is said to be a double edge sword because lesser and higher concentration of fluoride in drinking water can cause both dental and skeletal fluorosis. Fluoride is one of the important mineral usually present at a higher concentration in ground water. There are many researches being carried out for defluoridation method. In the present research, fluoride removal is demonstrated using banana peel which is a biowaste as a biocoagulant. Response Surface Methodology (RSM) is a statistical design tool which is used to design the experiment. Central Composite Design (CCD) was used to determine the influence of the pH and dosage of the coagulant on the optimal removal of fluoride from a simulated water sample. 895 of fluoride removal were obtained in a acidic pH range of 4 – 9 and bio coagulant dosage of dosage of 18 – 20mg/L.

Keywords: Fluoride, Response Surface Methodology, Dosage, banana peel

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1271 Estimating Tree Height and Forest Classification from Multi Temporal Risat-1 HH and HV Polarized Satellite Aperture Radar Interferometric Phase Data

Authors: Saurav Kumar Suman, P. Karthigayani

Abstract:

In this paper the height of the tree is estimated and forest types is classified from the multi temporal RISAT-1 Horizontal-Horizontal (HH) and Horizontal-Vertical (HV) Polarised Satellite Aperture Radar (SAR) data. The novelty of the proposed project is combined use of the Back-scattering Coefficients (Sigma Naught) and the Coherence. It uses Water Cloud Model (WCM). The approaches use two main steps. (a) Extraction of the different forest parameter data from the Product.xml, BAND-META file and from Grid-xxx.txt file come with the HH & HV polarized data from the ISRO (Indian Space Research Centre). These file contains the required parameter during height estimation. (b) Calculation of the Vegetation and Ground Backscattering, Coherence and other Forest Parameters. (c) Classification of Forest Types using the ENVI 5.0 Tool and ROI (Region of Interest) calculation.

Keywords: RISAT-1, classification, forest, SAR data

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1270 Foamability and Foam Stability of Gelatine-Sodium Dodecyl Sulfate Solutions

Authors: Virginia Martin Torrejon, Song Hang

Abstract:

Gelatine foams are widely explored materials due to their biodegradability, biocompatibility, and availability. They exhibit outstanding properties and are currently subject to increasing scientific research due to their potential use in different applications, such as biocompatible cellular materials for biomedical products or biofoams as an alternative to fossil-fuel-derived packaging. Gelatine is a highly surface-active polymer, and its concentrated solutions usually do not require surfactants to achieve low surface tension. Still, anionic surfactants like sodium dodecyl sulfate (SDS) strongly interact with gelatine, impacting its viscosity and rheological properties and, in turn, their foaming behaviour. Foaming behaviour is a key parameter for cellular solids produced by mechanical foaming as it has a significant effect on the processing and properties of cellular materials. Foamability mainly impacts the density and the mechanical properties of the foams, while foam stability is crucial to achieving foams with low shrinkage and desirable pore morphology. This work aimed to investigate the influence of SDS on the foaming behaviour of concentrated gelatine foams by using a dynamic foam analyser. The study of maximum foam height created, foam formation behaviour, drainage behaviour, and foam structure with regard to bubble size and distribution were carried out in 10 wt% gelatine solutions prepared at different SDS/gelatine concentration ratios. Comparative rheological and viscometry measurements provided a good correlation with the data from the dynamic foam analyser measurements. SDS incorporation at optimum dosages and gelatine gelation led to highly stable foams at high expansion ratios. The viscosity increase of the hydrogel solution at SDS content increased was a key parameter for foam stabilization. In addition, the impact of SDS content on gelling time and gel strength also considerably impacted the foams' stability and pore structure.

Keywords: dynamic foam analyser, gelatine foams stability and foamability, gelatine-surfactant foams, gelatine-SDS rheology, gelatine-SDS viscosity

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1269 Heating and Cooling Scenario of Blended Concrete Subjected to 780 Degrees Celsius

Authors: J. E. Oti, J. M. Kinuthia, R. Robinson, P. Davies

Abstract:

In this study, The Compressive strength of concretes made with Ground Granulated Blast furnace Slag (GGBS), pulverised Fuel Ash (PFA), rice Husk Ash (RHA) and Waste Glass Powder (WGP) after they were exposed 7800C (exposure duration of around 60 minutes) and then allowed to cool down gradually in the furnace for about 280 minutes at water binder ratio of 0.50 was investigated. GGBS, PFA, RHA and WGP were used to replace up to 20% Portland cement in the control concrete. Test for the determination of workability, compressive strength and tensile splitting strength of the concretes were carried out and the results were compared with control concrete. The test results showed that the compressive strength decreased by an average of around 30% after the concretes were exposed to the heating and cooling scenario.

Keywords: concrete, heating, cooling, pulverised fuel ash, rice husk ash, waste glass powder, GGBS, workability

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1268 Cr Induced Magnetization in Zinc-Blende ZnO-Based Diluted Magnetic Semiconductors

Authors: Bakhtiar Ul Haq, R. Ahmed, A. Shaari, Mazmira Binti Mohamed, Nisar Ali

Abstract:

The capability of exploiting the electronic charge and spin properties simultaneously in a single material has made diluted magnetic semiconductors (DMS) remarkable in the field of spintronics. We report the designing of DMS based on zinc-blend ZnO doped with Cr impurity. The full potential linearized augmented plane wave plus local orbital FP-L(APW+lo) method in density functional theory (DFT) has been adapted to carry out these investigations. For treatment of exchange and correlation energy, generalized gradient approximations have been used. Introducing Cr atoms in the matrix of ZnO has induced strong magnetic moment with ferromagnetic ordering at stable ground state. Cr:ZnO was found to favor the short range magnetic interaction that reflect the tendency of Cr clustering. The electronic structure of ZnO is strongly influenced in the presence of Cr impurity atoms where impurity bands appear in the band gap.

Keywords: ZnO, density functional theory, diluted agnetic semiconductors, ferromagnetic materials, FP-L(APW+lo)

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1267 12x12 MIMO Terminal Antennas Covering the Whole LTE and WiFi Spectrum

Authors: Mohamed Sanad, Noha Hassan

Abstract:

A broadband resonant terminal antenna has been developed. It can be used in different MIMO arrangements such as 2x2, 4x4, 8x8, or even 12x12 MIMO configurations. The antenna covers the whole LTE and WiFi bands besides the existing 2G/3G bands (700-5800 MHz), without using any matching/tuning circuits. Matching circuits significantly reduce the efficiency of any antenna and reduce the battery life. They also reduce the bandwidth because they are frequency dependent. The antenna can be implemented in smartphone handsets, tablets, laptops, notebooks or any other terminal. It is also suitable for different IoT and vehicle applications. The antenna is manufactured from a flexible material and can be bent or folded and shaped in any form to fit any available space in any terminal. It is self-contained and does not need to use the ground plane, the chassis or any other component of the terminal. Hence, it can be mounted on any terminal at different positions and configurations. Its performance does not get affected by the terminal, regardless of its type, shape or size. Moreover, its performance does not get affected by the human body of the terminal’s users. Because of all these unique features of the antenna, multiples of them can be simultaneously used for MIMO diversity coverage in any terminal device with a high isolation and a low correlation factor between them.

Keywords: IOT, LTE, MIMO, terminal antenna, WiFi

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1266 Study on Seismic Response Feature of Multi-Span Bridges Crossing Fault

Authors: Yingxin Hui

Abstract:

Understanding seismic response feature of the bridges crossing fault is the basis of the seismic fortification. Taking a multi-span bridge crossing active fault under construction as an example, the seismic ground motions at bridge site were generated following hybrid simulation methodology. Multi-support excitations displacement input models and nonlinear time history analysis was used to calculate seismic response of structures, and the results were compared with bridge in the near-fault region. The results showed that the seismic response features of bridges crossing fault were different from the bridges in the near-fault region. The design according to the bridge in near-fault region would cause the calculation results with insecurity and non-reasonable if the effect of cross the fault was ignored. The design of seismic fortification should be based on seismic response feature, which could reduce the adverse effect caused by the structure damage.

Keywords: bridge engineering, seismic response feature, across faults, rupture directivity effect, fling step

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1265 Hard Water Softening by Chronoamperometry and Impedancemetry

Authors: Samira Ghizellaoui, Manel Boumagoura, Rayane Menzri

Abstract:

The ground water Hamma rich in calcium and bicarbonate likely to deposit the tartar and subsequently lead to the obstruction of the pipes and the seizing of the stopping devices in addition to the financial losses resulting there from. It is therefore necessary to optimise an antiscaling treatment in order to avoid the risk of formation of tartar deposits in the various installations and to protect the equipment in contact with this water. MgCl2 is the chemical inhibitor which was tested. To optimise the effective concentration of this product, we used two electrochemical methods (chronoamperometry and impedancemetry) to identify the best method for optimizing antiscaling treatment. IR, RX, Raman spectroscopy and SEM indicate that the raw waters of Hamma give precipitates in the form of calcite (the most stable form), with the presence of a small amount of magnesian calcite and aragonite. In the presence of the inhibitor (MgCl2), calcium carbonate changes morphology to other forms that do not exist in the deposit obtained from the raw water (vaterite and calcium carbonate monohydrate).

Keywords: calcium carbonate, MgCl2, chronoamperometry, Impedancemetry

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1264 Gravity and Magnetic Survey, Modeling and Interpretation in the Blötberget Iron-Oxide Mining Area of Central Sweden

Authors: Ezra Yehuwalashet, Alireza Malehmir

Abstract:

Blötberget mining area in central Sweden, part of the Bergslagen mineral district, is well known for its various type of mineralization particularly iron-oxide deposits since the 1600. To shed lights on the knowledge of the host rock structures, depth extent and tonnage of the mineral deposits and support deep mineral exploration potential in the study area, new ground gravity and existing aeromagnetic data (from the Geological Survey of Sweden) were used for interpretations and modelling. A major boundary separating a gravity low from a gravity high in the southern part of the study area is noticeable and likely representing a fault boundary separating two different lithological units. Gravity data and modeling offers a possible new target area in the southeast of the known mineralization while suggesting an excess high-density region down to 800 m depth.

Keywords: gravity, magnetics, ore deposit, geophysics

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1263 Association of Mir-196a Expression in Esophageal Tissue with Barrett´s Esophagus and Esophageal Adenocarcinoma

Authors: Petra Borilova Linhartova, Michaela Ruckova, Sabina Sevcikova, Natalie Mlcuchova, Jan Bohm, Katerina Zukalova, Monika Vlachova, Jiri Dolina, Lumir Kunovsky, Radek Kroupa, Zdenek Pavlovsky, Zdenek Danek, Tereza Deissova, Lydie Izakovicova Holla, Ondrej Slaby, Zdenek Kala

Abstract:

Esophageal adenocarcinoma (EAC) is a highly aggressive malignancy that frequently develops from Barrett's esophagus (BE), a premalignant pathologic change occurring in the lower end of the esophagus. Specific microRNAs (miRNAs), small non-coding RNAs that function as posttranscriptional regulators of gene expression, were repeatedly proved to play key roles in the pathogenesis of these diseases. This pilot study aimed to analyze four selected miRNAs in esophageal tissues from healthy controls (HC) and patients with reflux esophagitis (RE)/BE/EAC, as well as to compare expression at the site of Barrett's mucosa/adenocarcinoma and healthy esophageal tissue outside the area of the main pathology in patients with BE/EAC. In this pilot study, 22 individuals (3 HC, 8 RE, 5 BE, 6 EAC) were included and endoscopically examined. RNA was isolated from the fresh-frozen esophageal tissue (stored in the RNAlater™ Stabilization Solution −70°C) using the AllPrep DNA/RNA/miRNA Universal Kit. Subsequent RT-qPCR analysis was performed using selected TaqMan MicroRNA Assays for miR-21, miR-34a, miR-196a, miR-196b, and endogenous control (RNU44). While the expression of miR-21 in the esophageal tissue with the main pathology was decreased in BE and EAC patients in comparison to the group of HC and RE patients (p=0.01), the expression of miR-196a was increased in the BE and EAC patients (p<0.01). Correlations between those miRNAs expression in tissue and severity of diagnosis were observed (p<0.05). In addition, miR-196a was significantly more expressed at the site with the main pathology than in paired adjacent esophageal tissue in BE and EAC patients (p<0.01). In conclusion, our pilot results showed that miR-196a, which regulates the proliferation, invasion, and migration (and was previously associated with esophageal squamous cell carcinoma and marked as a potential therapeutic target), could be a diagnostic tissue biomarker for BE and EAC as well.

Keywords: microRNA, barrett´s esophagus, esophageal adenocarcinoma, biomarker

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1262 A Review on Development of Pedicle Screws and Characterization of Biomaterials for Fixation in Lumbar Spine

Authors: Shri Dubey, Jamal Ghorieshi

Abstract:

Instability of the lumbar spine is caused by various factors that include degenerative disc, herniated disc, traumatic injuries, and other disorders. Pedicle screws are widely used as a main fixation device to construct rigid linkages of vertebrae to provide a fully functional and stable spine. Various technologies and methods have been used to restore the stabilization. However, loosening of pedicle screws is the main cause of concerns for neurosurgeons. This could happen due to poor bone quality with osteoporosis as well as types of pedicle screw used. Compatibilities and stabilities of pedicle screws with bone depend on design (thread design, length, and diameter) and material. Grip length and pullout strength affect the motion and stability of the spine when it goes through different phases such as extension, flexion, and rotation. Pullout strength of augmented pedicle screws is increased in both primary and salvage procedures by 119% (p = 0.001) and 162% (p = 0.01), respectively. Self-centering pedicle screws at different trajectories (0°, 10°, 20°, and 30°) show the same pullout strength as insertion in a straight-ahead trajectory. The outer cylindrical and inner conical shape of pedicle screws show the highest pullout strength in Grades 5 and 15 foams (synthetic bone). An outer cylindrical and inner conical shape with a V-shape thread exhibit the highest pullout strength in all foam grades. The maximum observed pullout strength is at axial pullout configuration at 0°. For Grade 15 (240 kg/m³) foam, there is a decline in pull out strength. The largest decrease in pullout strength is reported for Grade 10 (160 kg/m³) foam. The maximum pullout strength of 2176 N (0.32-g/cm³ Sawbones) on all densities. Type 1 Pedicle screw shows the best fixation due to smaller conical core diameter and smaller thread pitch (Screw 2 with 2 mm; Screws 1 and 3 with 3 mm).

Keywords: polymethylmethacrylate, PMMA, classical pedicle screws, CPS, expandable poly-ether-ether-ketone shell, EPEEKS, includes translaminar facet screw, TLFS, poly-ether-ether-ketone, PEEK, transfacetopedicular screw, TFPS

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1261 Effect of Dynamic Loading by Cyclic Triaxial Tests on Sand Stabilized with Cement

Authors: Priyanka Devi, Mohammad Muzzaffar Khan, G. Kalyan Kumar

Abstract:

Liquefaction of saturated soils due to dynamic loading is an important and interesting area in the field of geotechnical earthquake engineering. When the soil liquefies, the structures built on it develops uneven settlements thereby producing cracks in the structure and weakening the foundation. The 1964 Alaskan Good Friday earthquake, the 1989 San Francisco earthquake and 2011 Tōhoku earthquake are some of the examples of liquefaction occurred due to an earthquake. To mitigate the effect of liquefaction, several methods such use of stone columns, increasing the vertical stress, compaction and removal of liquefiable soil are practiced. Grouting is one of those methods used to increase the strength of the foundation and develop resistance to liquefaction of soil without affecting the superstructure. In the present study, an attempt has been made to investigate the undrained cyclic behavior of locally available soil, stabilized by cement to mitigate the seismically induced soil liquefaction. The specimens of 75mm diameter and 150mm height were reconstituted in the laboratory using water sedimentation technique. A series of strain-controlled cyclic triaxial tests were performed on saturated soil samples followed by consolidation. The effects of amplitude, confining pressure and relative density on the dynamic behavior of sand was studied for soil samples with varying cement content. The results obtained from the present study on loose specimens and medium dense specimens indicate that (i) the higher the relative density, the more will be the liquefaction resistance, (ii) with increase of effective confining pressure, a decrease in developing of excess pore water pressure during cyclic loading was observed and (iii) sand specimens treated with cement showed reduced excess pore pressures and increased liquefaction resistance suggesting it as one of the mitigation methods.

Keywords: cyclic triaxial test, liquefaction, soil-cement stabilization, pore pressure ratio

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1260 Time-Dependent Density Functional Theory of an Oscillating Electron Density around a Nanoparticle

Authors: Nilay K. Doshi

Abstract:

A theoretical probe describing the excited energy states of the electron density surrounding a nanoparticle (NP) is presented. An electromagnetic (EM) wave interacts with a NP much smaller than the incident wavelength. The plasmon that oscillates locally around the NP comprises of excited conduction electrons. The system is based on the Jellium model of a cluster of metal atoms. Hohenberg-Kohn (HK) equations and the variational Kohn-Sham (SK) scheme have been used to obtain the NP electron density in the ground state. Furthermore, a time-dependent density functional (TDDFT) theory is used to treat the excited states in a density functional theory (DFT) framework. The non-interacting fermionic kinetic energy is shown to be a functional of the electron density. The time dependent potential is written as the sum of the nucleic potential and the incoming EM field. This view of the quantum oscillation of the electron density is a part of the localized surface plasmon resonance.

Keywords: electron density, energy, electromagnetic, DFT, TDDFT, plasmon, resonance

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1259 An Investigation on the Perception and Adoption of Terminology Management Applications by the Iranian English Language Translators

Authors: Abdul Amir Hazbavi

Abstract:

In recent years, there have been increasing requests in the field of translation studies to develop software facilitating the analysis of corpora. One of the specialized tools in that regard are Terminology Management Tools. Briefly explaining, Terminology Management Tools are applications developed to help create and store terminological data in the form which allows for a controlled use of the data. While it has a long history and an established ground in translation market in most parts of the globe, the Iranian translators and translation market still seem to be unaware or unfamiliar with Terminology Management Tools. In order to provide a preview on the perception and adoption of Terminology Management Tools by the Iranian translators, the present survey was carried out among 224 last-year undergraduate Iranian students of English translation at 10 different universities across the country. The study revealed a very low level of adoption and a very high level of willingness to get familiar with and learn about Terminology Management Tools by the Iranian translators.

Keywords: translation, translation technology, terminology management tools, terminology management survey

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1258 Safe and Scalable Framework for Participation of Nodes in Smart Grid Networks in a P2P Exchange of Short-Term Products

Authors: Maciej Jedrzejczyk, Karolina Marzantowicz

Abstract:

Traditional utility value chain is being transformed during last few years into unbundled markets. Increased distributed generation of energy is one of considerable challenges faced by Smart Grid networks. New sources of energy introduce volatile demand response which has a considerable impact on traditional middlemen in E&U market. The purpose of this research is to search for ways to allow near-real-time electricity markets to transact with surplus energy based on accurate time synchronous measurements. A proposed framework evaluates the use of secure peer-2-peer (P2P) communication and distributed transaction ledgers to provide flat hierarchy, and allow real-time insights into present and forecasted grid operations, as well as state and health of the network. An objective is to achieve dynamic grid operations with more efficient resource usage, higher security of supply and longer grid infrastructure life cycle. Methods used for this study are based on comparative analysis of different distributed ledger technologies in terms of scalability, transaction performance, pluggability with external data sources, data transparency, privacy, end-to-end security and adaptability to various market topologies. An intended output of this research is a design of a framework for safer, more efficient and scalable Smart Grid network which is bridging a gap between traditional components of the energy network and individual energy producers. Results of this study are ready for detailed measurement testing, a likely follow-up in separate studies. New platforms for Smart Grid achieving measurable efficiencies will allow for development of new types of Grid KPI, multi-smart grid branches, markets, and businesses.

Keywords: autonomous agents, Distributed computing, distributed ledger technologies, large scale systems, micro grids, peer-to-peer networks, Self-organization, self-stabilization, smart grids

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1257 Wastewater Treatment Using Sodom Apple Tree in Arid Regions

Authors: D. Oulhaci, M. Zehah, S. Meguellati

Abstract:

Collected by the sewerage network, the wastewater contains many polluting elements, coming from the population, commercial, industrial and agricultural activities. These waters are collected and discharged into the natural environment and pollute it. Hence the need to transport them before discharge to a treatment plant to undergo several treatment phases. The objective of this study is to highlight the purification performance of the "Sodom apple tree" which is a very common shrub in the region of Djanet and Illizi in Algeria. As material, we used small buckets filled with sand with a gravel substrate. We sowed seeds that we let grow a few weeks. The water supply is under a horizontal flow regime under-ground. The urban wastewater used is preceded by preliminary treatment. The water obtained after purification is collected using a tap in a container placed under the seal. The comparison between the inlet and the outlet waters showed that the presence of the Sodom apple tree contributes to reducing their pollutant parameters with significant rates: 81% for COD, 84%, for BOD , 95% for SM , 82% for NO⁻² , and 85% for NO⁻³ and can be released into the environment without risk of pollution

Keywords: arid zone, pollution, purification, re-use, wastewater.

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1256 Analysis and Prediction of the Behavior of the Landslide at Ain El Hammam, Algeria Based on the Second Order Work Criterion

Authors: Zerarka Hizia, Akchiche Mustapha, Prunier Florent

Abstract:

The landslide of Ain El Hammam (AEH) is characterized by a complex geology and a high hydrogeology hazard. AEH's perpetual reactivation compels us to look closely at its triggers and to better understand the mechanisms of its evolution in mass and in depth. This study builds a numerical model to simulate the influencing factors such as precipitation, non-saturation, and pore pressure fluctuations, using Plaxis software. For a finer analysis of instabilities, we use Hill's criterion, based on the sign of the second order work, which is the most appropriate material stability criterion for non-associated elastoplastic materials. The results of this type of calculation allow us, in theory, to predict the shape and position of the slip surface(s) which are liable to ground movements of the slope, before reaching the rupture given by the plastic limit of Mohr Coulomb. To validate the numerical model, an analysis of inclinometer measures is performed to confirm the direction of movement and kinematic of the sliding mechanism of AEH’s slope.

Keywords: landslide, second order work, precipitation, inclinometers

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1255 Effect of Different Contact Rollers on the Surface Texture during the Belt Grinding Process

Authors: Amine Hamdi, Sidi Mohammed Merghache, Brahim Fernini

Abstract:

During abrasive machining of hard steels by belt grinding, the finished surface texture is influenced by the pressure between the abrasive belt and the workpiece; this pressure is the force applied by the contact roller on the workpiece. Therefore, the contact roller has an important role and has a direct impact on process efficiency. The objective of this article is to study and compare the influence of different contact rollers on the belt ground surface texture. The quality of the surface texture is characterized by eight roughness parameters (Ra, Rz, Rp, Rv, Rsk, Rku, Rsm, and Rdq) and five parameters of the bearing area curve (Rpk, Rk, Rvk, Mr1, and Mr2). The results of the experimental tests indicate a better surface texture obtained by the PA 6 polyamide roller (hardness 60 Shore D) compared to that obtained with other rollers of the same hardness or of different hardness. Simultaneously, optimum medium pressure between the belt and the workpiece allows chip removal without fracturing the abrasive grains. This generates a good surface texture.

Keywords: belt grinding, contact roller, pressure, abrasive belt, surface texture

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1254 Studies on the Solubility of Oxygen in Water Using a Hose to fill the Air with Different Shapes

Authors: Wichan Lertlop

Abstract:

This research is to study the solubility of oxygen in water taking the form of aeration pipes that have different shaped objectives of the research to compare the amount of oxygen dissolved in the water, whice take the form of aeration pipes. Shaped differently When aeration 5 minutes on air for 10 minutes, and when air fills 30 minutes, as well as compare the durability of the oxygen is dissolved in the water of the inlet air refueling shaped differently when you fill the air 30 minutes and when. aeration and 60 minutes populations used in this study, the population of pond water from Rajabhat University in February 2014 used in this study consists of 1. Aerator 2. Hose using a hose to fill the air with 3 different shape, different shapes pyramid whose base is on the water tank. Shaped rectangular water tank onto the ground. And shapes in a vertical pipe. 3 meter, dissolved oxygen, dissolved in water to get the calibration standard. 4. The clock for timer 5. Three water tanks which are 39 cm wide, 51 cm long and 32 cm high.

Keywords: aeration, dissolve oxygen, different shapes

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1253 Seizure Effects of FP Bearings on the Seismic Reliability of Base-Isolated Systems

Authors: Paolo Castaldo, Bruno Palazzo, Laura Lodato

Abstract:

This study deals with the seizure effects of friction pendulum (FP) bearings on the seismic reliability of a 3D base-isolated nonlinear structural system, designed according to Italian seismic code (NTC08). The isolated system consists in a 3D reinforced concrete superstructure, a r.c. substructure and the FP devices, described by employing a velocity dependent model. The seismic input uncertainty is considered as a random variable relevant to the problem, by employing a set of natural seismic records selected in compliance with L’Aquila (Italy) seismic hazard as provided from NTC08. Several non-linear dynamic analyses considering the three components of each ground motion have been performed with the aim to evaluate the seismic reliability of the superstructure, substructure, and isolation level, also taking into account the seizure event of the isolation devices. Finally, a design solution aimed at increasing the seismic robustness of the base-isolated systems with FPS is analyzed.

Keywords: FP devices, seismic reliability, seismic robustness, seizure

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1252 Active Flutter Suppression of Sports Aircraft Tailplane by Supplementary Control Surface

Authors: Aleš Kratochvíl, Svatomír Slavík

Abstract:

The paper presents an aircraft flutter suppression by active damping of supplementary control surface at trailing edge. The mathematical model of thin oscillation airfoil with control surface driven by pilot is developed. The supplementary control surface driven by control law is added. Active damping of flutter by several control law is present. The structural model of tailplane with an aerodynamic strip theory based on the airfoil model is developed by a finite element method. The optimization process of stiffens parameters is carried out to match the structural model with results from a ground vibration test of a small sport airplane. The implementation of supplementary control surface driven by control law is present. The active damping of tailplane model is shown.

Keywords: active damping, finite element method, flutter, tailplane model

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1251 Development of a Weed Suppression Robot for Rice Cultivation Weed Suppression and Posture Control

Authors: Shohei Nakai, Yasuhiro Yamada

Abstract:

Weed suppression and weeding are necessary measures for rice cultivation. Weed suppression precedes the process of weeding. It means suppressing the growth of young weeds and creating a weed-less environment. If we suppress the growth of weeds, we can reduce the number of weeds in a paddy field. This would result in a reduction of the weeding work load. In this paper, we will show how we developed a weed suppression robot for the purpose of reducing the weeding work load. The robot has a laser range finder for autonomous mobility and a robot arm for weed suppression. It travels along the rice rows without stepping on and injuring the rice plants in a paddy field. The robot arm applies force to the weed seedlings and thereby suppresses the growth of weeds. This paper will explain the methodology of the autonomous mobile, the experiment in weed suppression, and the method of controlling the robot’s posture on uneven ground.

Keywords: mobile robot, paddy field, robot arm, weed

Procedia PDF Downloads 377
1250 Analysis of the Benefits of Motion Simulators in 5th Generation Fighter Pilots' Training

Authors: Ali Mithad Emre

Abstract:

In military aviation, the use of flight simulators has proliferated recently in order to train fifth generation fighter pilots. With these simulators, pilots can carry out real-time flights resulting in seeing their faults and can perform emergency drills prior to real flights. Since we cannot risk losing the aircraft and the pilot himself/herself in the flight training process, flight simulators are of great importance to adapt the fighter pilots competently to real flights aboard the fifth generation aircraft. The real flights are impossible to simulate thoroughly on the ground. To some extent, the fixed-based simulators may assist the pilot to steer aircraft technically and visually but flight simulators can’t trick the pilot’s vestibular, sensory, and perceptual systems without motion platforms. This paper discusses the benefits of motion simulators for fifth generation fighter pilots’ training in preference to the fixed-based counterparts by analyzing their pros and cons.

Keywords: military, pilot, sickness, simulator

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1249 Development of a Three-Dimensional-Flywheel Robotic System

Authors: Chung-Chun Hsiao, Yu-Kai, Ting, Kai-Yuan Liu, Pang-Wei Yen, Jia-Ying Tu

Abstract:

In this paper, a new design of spherical robotic system based on the concepts of gimbal structure and gyro dynamics is presented. Robots equipped with multiple wheels and complex steering mechanics may increase the weight and degrade the energy transmission efficiency. In addition, the wheeled and legged robots are relatively vulnerable to lateral impact and lack of lateral mobility. Therefore, the proposed robotic design uses a spherical shell as the main body for ground locomotion, instead of using wheel devices. Three spherical shells are structured in a similar way to a gimbal device and rotate like a gyro system. The design and mechanism of the proposed robotic system is introduced. In addition, preliminary results of the dynamic model based on the principles of planar rigid body kinematics and Lagrangian equation are included. Simulation results and rig construction are presented to verify the concepts.

Keywords: gyro, gimbal, lagrange equation, spherical robots

Procedia PDF Downloads 314
1248 Application of Laser-Induced Breakdown Spectroscopy for the Evaluation of Concrete on the Construction Site and in the Laboratory

Authors: Gerd Wilsch, Tobias Guenther, Tobias Voelker

Abstract:

In view of the ageing of vital infrastructure facilities, a reliable condition assessment of concrete structures is becoming of increasing interest for asset owners to plan timely and appropriate maintenance and repair interventions. For concrete structures, reinforcement corrosion induced by penetrating chlorides is the dominant deterioration mechanism affecting the serviceability and, eventually, structural performance. The determination of the quantitative chloride ingress is required not only to provide valuable information on the present condition of a structure, but the data obtained can also be used for the prediction of its future development and associated risks. At present, wet chemical analysis of ground concrete samples by a laboratory is the most common test procedure for the determination of the chloride content. As the chloride content is expressed by the mass of the binder, the analysis should involve determination of both the amount of binder and the amount of chloride contained in a concrete sample. This procedure is laborious, time-consuming, and costly. The chloride profile obtained is based on depth intervals of 10 mm. LIBS is an economically viable alternative providing chloride contents at depth intervals of 1 mm or less. It provides two-dimensional maps of quantitative element distributions and can locate spots of higher concentrations like in a crack. The results are correlated directly to the mass of the binder, and it can be applied on-site to deliver instantaneous results for the evaluation of the structure. Examples for the application of the method in the laboratory for the investigation of diffusion and migration of chlorides, sulfates, and alkalis are presented. An example for the visualization of the Li transport in concrete is also shown. These examples show the potential of the method for a fast, reliable, and automated two-dimensional investigation of transport processes. Due to the better spatial resolution, more accurate input parameters for model calculations are determined. By the simultaneous detection of elements such as carbon, chlorine, sodium, and potassium, the mutual influence of the different processes can be determined in only one measurement. Furthermore, the application of a mobile LIBS system in a parking garage is demonstrated. It uses a diode-pumped low energy laser (3 mJ, 1.5 ns, 100 Hz) and a compact NIR spectrometer. A portable scanner allows a two-dimensional quantitative element mapping. Results show the quantitative chloride analysis on wall and floor surfaces. To determine the 2-D distribution of harmful elements (Cl, C), concrete cores were drilled, split, and analyzed directly on-site. Results obtained were compared and verified with laboratory measurements. The results presented show that the LIBS method is a valuable addition to the standard procedures - the wet chemical analysis of ground concrete samples. Currently, work is underway to develop a technical code of practice for the application of the method for the determination of chloride concentration in concrete.

Keywords: chemical analysis, concrete, LIBS, spectroscopy

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1247 MIMO UWB Antenna for Exploring Body Centric Communication

Authors: Osama Aziz, Hamza Ahmad, Muhibur Rahman

Abstract:

The performance of wireless communication systems has been suggested to be improved by UWB MIMO antenna systems. However, creating a successful UWB MIMO antenna is a difficult undertaking that calls for resolving a number of design issues, including radiation efficiency, size, and frequency range. This study's primary objective is to create a novel, highly effective, small-sized, ultra-wideband (UWB) multiple-input multiple-output (MIMO) antenna and investigate its potential applications in body-centric communication. Two radiating elements, shared ground plane, circular stubs, and t-shaped isolation elements are used to achieve the MIMO antenna. Outstanding multiplexing efficiency, significant peak gain across the entire UWB frequency spectrum, extremely low mutual coupling (S21=-16 dB), high diversity gain (DG>9), and low envelop correlation are achieved. The proposed antenna will be one of the promising candidates for body centric communication.

Keywords: UWB communication, UWB MIMO antennas, body-centric communication, diversity gain

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1246 Symmetry-Protected Dirac Semi-Metallic Phases in Transition Metal Dichalcogenides

Authors: Mohammad Saeed Bahramy

Abstract:

Transition metal dichalcogenides have experienced a resurgence of interest in the past few years owing to their rich properties, ranging from metals and superconductors to strongly spin-orbit-coupled semiconductors and charge-density-wave systems. In all these cases, the transition metal d-electrons mainly determine the ground state properties. This presentation focuses on the chalcogen-derived states. Combining density-functional theory calculations with spin- and angle-resolved photoemission, it is shown that these states generically host a coexistence of type I and type II three-dimensional bulk Dirac fermions as well as ladders of topological surface states and surface resonances. It will be discussed how these naturally arise within a single p-orbital manifold as a general consequence of a trigonal crystal field, and as such can be expected across many compounds. Our finding opens a new route to design topological materials with advanced functionalities.

Keywords: topology, electronic structure, Dirac semimetals, transition metal dichalcogenides

Procedia PDF Downloads 166