Search results for: optical density
4601 Investigation of Glacier Activity Using Optical and Radar Data in Zardkooh
Authors: Mehrnoosh Ghadimi, Golnoush Ghadimi
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Precise monitoring of glacier velocity is critical in determining glacier-related hazards. Zardkooh Mountain was studied in terms of glacial activity rate in Zagros Mountainous region in Iran. In this study, we assessed the ability of optical and radar imagery to derive glacier-surface velocities in mountainous terrain. We processed Landsat 8 for optical data and Sentinel-1a for radar data. We used methods that are commonly used to measure glacier surface movements, such as cross correlation of optical and radar satellite images, SAR tracking techniques, and multiple aperture InSAR (MAI). We also assessed time series glacier surface displacement using our modified method, Enhanced Small Baseline Subset (ESBAS). The ESBAS has been implemented in StaMPS software, with several aspects of the processing chain modified, including filtering prior to phase unwrapping, topographic correction within three-dimensional phase unwrapping, reducing atmospheric noise, and removing the ramp caused by ionosphere turbulence and/or orbit errors. Our findings indicate an average surface velocity rate of 32 mm/yr in the Zardkooh mountainous areas.Keywords: active rock glaciers, landsat 8, sentinel-1a, zagros mountainous region
Procedia PDF Downloads 724600 Monitoring the Railways by Means of C-OTDR Technology
Authors: Andrey V. Timofeev
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This paper presents development results of the method of seismoacoustic activity monitoring based on usage vibrosensitive properties of optical fibers. Analysis of Rayleigh backscattering radiation parameters changes, which take place due to microscopic seismoacoustic impacts on the optical fiber, allows to determine seismoacoustic emission sources positions and to identify their types. Results of using this approach are successful for complex monitoring of railways.Keywords: C-OTDR systems, monitoring of railways, Rayleigh backscattering, eismoacoustic activity
Procedia PDF Downloads 3854599 Density of Introduced Birds (Sturnidae: Mynas) in Urban Areas of Kuching and Samarahan, Sarawak, Malaysia
Authors: Mustafa Abdul Rahman, Maisarah Abdullah, Nurfarahin Azizan, Mohd-Azlan Jayasilan, Andrew Alek Tuen
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Common myna (Acridotheres tristis) and Javan myna (A. javanicus) belong to the family Sturnidae. These two species range from Iran, Afghanistan, and east through the Indian subcontinent to south China, Indochina and the mainland Southeast Asia. It was introduced to Sarawak in 1980’s and since then the population has increased tremendously. A study to determine the density of these two species was conducted in the Kuching and Samarahan Districts, Sarawak, Malaysian Borneo between November 2013 and January 2014. In Kuching City a total of 12 transect lines of 500 m each were established totaling 6 km. In Samarahan District, six 500 m transect lines were established both within Universiti Malaysia Sarawak (UNIMAS) campus and in Serian Town totaling 6 km. The results showed that the density of Javan myna in Kuching City (east) was 13.9 birds/ha, Kuching City (center) was 21.3 birds/ha and Kuching City (west) was 43.1 birds/ha. The density of common myna at UNIMAS campus was 20.3 birds/ha and Serian Town was 13.2 birds/ha. The density of human population probably plays an important role in determining the density of mynas in an area as it is associated with the availability of food sources, roosting and nesting places originating from human activity.Keywords: density, myna, transect, invasive, Sarawak, Borneo
Procedia PDF Downloads 5704598 Silicon Surface Treatment Effect on the Structural, Optical, and Optoelectronic Properties for Solar Cell Applications
Authors: Lotfi Hedi Khezami, Mohamed Ben Rabha, N. Sboui, Mounir Gaidi, B. Bessais
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Metal-nano particle-assisted Chemical Etching is an extraordinary developed wet etching method of producing uniform semiconductor nano structure (nano wires) from patterned metallic film on crystalline silicon surface. The metal films facilitate the etching in HF and H2O2 solution and produce silicon nanowires (SiNWs). Creation of different SiNWs morphologies by changing the etching time and its effects on optical and opto electronic properties was investigated. Combination effect of formed SiNWs and stain etching treatment in acid (HF/HNO3/H2O) solution on the surface morphology of Si wafers as well as on the optical and opto electronic properties are presented in this paper.Keywords: stain etching, porous silicon, silicon nanowires, reflectivity, lifetime, solar cells
Procedia PDF Downloads 4434597 Effect of Substrate Concentration and Pulp Density on Bioleaching of Metals from as Received Spent Refinery Catalyst
Authors: Haragobinda Srichandan, Ashish Pathak, Dong Jin Kim, Seoung-Won Lee
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The present investigation deals with bioleaching of spent refinery catalyst (as received) using At. thiooxidans. The effect of substrate concentration and pulp density was studied. XPS analysis concluded that the metals in spent catalyst were present as both sulfide and oxides. The dissolution behavior of metals during bioleaching was different. During bioleaching, higher dissolution of Ni and lower dissolution of Mo, V and Al was observed. An increase in pulp density from 1% to 10% led to a decrease in leaching yields of all the metals. This was due to the substantial increase in medium pH at higher pulp densities. The maximum negative impact of pulp density was observed on the leaching yield of V. An increase in sulfur concentration from 0.5% to 2.5% didn’t bring positive impact on metal leaching yield. 0.5% sulfur was found to be the optimum above which no significant increase in leaching yields of metals was observed.Keywords: At. thiooxidans, pulp density, spent catalyst, bioleaching
Procedia PDF Downloads 3584596 The High Precision of Magnetic Detection with Microwave Modulation in Solid Spin Assembly of NV Centres in Diamond
Authors: Zongmin Ma, Shaowen Zhang, Yueping Fu, Jun Tang, Yunbo Shi, Jun Liu
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Solid-state quantum sensors are attracting wide interest because of their high sensitivity at room temperature. In particular, spin properties of nitrogen–vacancy (NV) color centres in diamond make them outstanding sensors of magnetic fields, electric fields and temperature under ambient conditions. Much of the work on NV magnetic sensing has been done so as to achieve the smallest volume, high sensitivity of NV ensemble-based magnetometry using micro-cavity, light-trapping diamond waveguide (LTDW), nano-cantilevers combined with MEMS (Micro-Electronic-Mechanical System) techniques. Recently, frequency-modulated microwaves with continuous optical excitation method have been proposed to achieve high sensitivity of 6 μT/√Hz using individual NV centres at nanoscale. In this research, we built-up an experiment to measure static magnetic field through continuous wave optical excitation with frequency-modulated microwaves method under continuous illumination with green pump light at 532 nm, and bulk diamond sample with a high density of NV centers (1 ppm). The output of the confocal microscopy was collected by an objective (NA = 0.7) and detected by a high sensitivity photodetector. We design uniform and efficient excitation of the micro strip antenna, which is coupled well with the spin ensembles at 2.87 GHz for zero-field splitting of the NV centers. Output of the PD signal was sent to an LIA (Lock-In Amplifier) modulated signal, generated by the microwave source by IQ mixer. The detected signal is received by the photodetector, and the reference signal enters the lock-in amplifier to realize the open-loop detection of the NV atomic magnetometer. We can plot ODMR spectra under continuous-wave (CW) microwave. Due to the high sensitivity of the lock-in amplifier, the minimum detectable value of the voltage can be measured, and the minimum detectable frequency can be made by the minimum and slope of the voltage. The magnetic field sensitivity can be derived from η = δB√T corresponds to a 10 nT minimum detectable shift in the magnetic field. Further, frequency analysis of the noise in the system indicates that at 10Hz the sensitivity less than 10 nT/√Hz.Keywords: nitrogen-vacancy (NV) centers, frequency-modulated microwaves, magnetic field sensitivity, noise density
Procedia PDF Downloads 4314595 The Association of Slope Failure and Lineament Density along the Ranau-Tambunan Road, Sabah, Malaysia
Authors: Norbert Simon, Rodeano Roslee, Abdul Ghani Rafek, Goh Thian Lai, Azimah Hussein, Lee Khai Ern
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The 54 km stretch of Ranau-Tambunan (RTM) road in Sabah is subjected to slope failures almost every year. This study is focusing on identifying section of roads that are susceptible to failure based on temporal landslide density and lineament density analyses. In addition to the analyses, the rock slopes in several sections of the road were assessed using the geological strength index (GSI) technique. The analysis involved 148 landslides that were obtained in 1978, 1994, 2009 and 2011. The landslides were digitized as points and the point density was calculated based on every 1km2 of the road. The lineaments of the area was interpreted from Landsat 7 15m panchromatic band. The lineament density was later calculated based on every 1km2 of the area using similar technique with the slope failure density calculation. The landslide and lineament densities were classified into three different classes that indicate the level of susceptibility (low, moderate, high). Subsequently, the two density maps were overlap to produce the final susceptibility map. The combination of both high susceptibility classes from these maps signifies the high potential of slope failure in those locations in the future. The final susceptibility map indicates that there are 22 sections of the road that are highly susceptible. Seven rock slopes were assessed along the RTM road using the GSI technique. It was found from the assessment that rock slopes along this road are highly fractured, weathered and can be classified into fair to poor categories. The poor condition of the rock slope can be attributed to the high lineament density that presence in the study area. Six of the rock slopes are located in the high susceptibility zones. A detailed investigation on the 22 high susceptibility sections of the RTM road should be conducted due to their higher susceptibility to failure, in order to prevent untoward incident to road users in the future.Keywords: GSI, landslide, landslide density, landslide susceptibility, lineament density
Procedia PDF Downloads 3904594 Thiourea Modified Cadmium Sulfide Film for Solar Cell Application
Authors: Rupali Mane
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Cadmium sulfide (Cds) thin films were chemically deposited at room temperature, from aqueous ammonia solution using CdCl₂ (Cadmium chloride) as a Cd²⁺ and CS(NH₂)₂ (Thiourea) as S² ion sources. ‘as-deposited’ films were uniform, well adherent to the glass substrate, secularly reflective and yellowish in color. The ‘as-deposited ’Cds layers grew with nano-crystalline in nature and exhibit cubic structure, with blue-shift in optical band gap. The films were annealed in air atmosphere for two hours at different temperatures and further characterized for compositional, structural, morphological and optical properties. The XRD and SEM studies clearly revealed the systematic changes in morphological and structural form of Cds films with an improvement in the crystal quality. The annealed films showed ‘red-shift’ in the optical spectra after thermal treatment. The Thiourea modified CdS film could be good to provide solar cell application.Keywords: cadmium sulfide, thin films, nano-crystalline, XRD
Procedia PDF Downloads 3394593 Coral Reef Fishes in the Marine Protected Areas in Southern Cebu, Philippines
Authors: Christine M. Corrales, Gloria G. Delan, Rachel Luz V. Rica, Alfonso S. Piquero
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Marine protected areas (MPAs) in the study sites were established 8-13 years ago and are presently operational. This study was conducted to gather baseline information on the diversity, density and biomass of coral reef fishes inside and outside the four marine protected areas (MPAs) of Cawayan, Dalaguete; Daan-Lungsod Guiwang, Alcoy; North Granada, Boljoon and Sta. Cruz, Ronda. Coral reef fishes in the MPAs were identified using Fish Visual Census Method. Results of the t-test showed that the mean diversity (fish species/250m2) of target and non-target reef fish species found inside and outside the MPAs were significantly different. Density (ind./1,000m2) of target species inside and outside the MPAs showed no significant difference. Similarly, density of non-target species inside and outside the MPAs also showed no significant difference. This is an indication that fish density inside and outside the MPAs were more or less of the same condition. The mean biomass (kg/1,000m2) of target species inside and outside the MPAs showed a significant difference in contrast with non-target species inside and outside the MPAs which showed a no significant difference. Higher biomass of target fish species belonging to family Caesonidae (fusiliers) and Scaridae (parrotfishes) were commonly observed inside the MPAs. Results showed that fish species were more diverse with higher density and biomass inside the MPAs than the outside area. However, fish diversity and density were mostly contributed by non-target species. Hence, long term protection and management of MPAs is needed to effectively increase fish diversity, density and biomass specifically on target fish species.Keywords: biomass, density, diversity, marine protected area, target fish species
Procedia PDF Downloads 3854592 A Comparative Study on Optimized Bias Current Density Performance of Cubic ZnB-GaN with Hexagonal 4H-SiC Based Impatts
Authors: Arnab Majumdar, Srimani Sen
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In this paper, a vivid simulated study has been made on 35 GHz Ka-band window frequency in order to judge and compare the DC and high frequency properties of cubic ZnB-GaN with the existing hexagonal 4H-SiC. A flat profile p+pnn+ DDR structure of impatt is chosen and is optimized at a particular bias current density with respect to efficiency and output power taking into consideration the effect of mobile space charge also. The simulated results obtained reveals the strong potentiality of impatts based on both cubic ZnB-GaN and hexagonal 4H-SiC. The DC-to-millimeter wave conversion efficiency for cubic ZnB-GaN impatt obtained is 50% with an estimated output power of 2.83 W at an optimized bias current density of 2.5×108 A/m2. The conversion efficiency and estimated output power in case of hexagonal 4H-SiC impatt obtained is 22.34% and 40 W respectively at an optimum bias current density of 0.06×108 A/m2.Keywords: cubic ZnB-GaN, hexagonal 4H-SiC, double drift impatt diode, millimetre wave, optimised bias current density, wide band gap semiconductor
Procedia PDF Downloads 3524591 Density functional (DFT), Study of the Structural and Phase Transition of ThC and ThN: LDA vs GGA Computational
Authors: Hamza Rekab Djabri, Salah Daoud
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The present paper deals with the computational of structural and electronic properties of ThC and ThN compounds using density functional theory within generalized-gradient (GGA) apraximation and local density approximation (LDA). We employ the full potential linear muffin-tin orbitals (FP-LMTO) as implemented in the Lmtart code. We have used to examine structure parameter in eight different structures such as in NaCl (B1), CsCl (B2), ZB (B3), NiAs (B8), PbO (B10), Wurtzite (B4) , HCP (A3) βSn (A5) structures . The equilibrium lattice parameter, bulk modulus, and its pressure derivative were presented for all calculated phases. The calculated ground state properties are in good agreement with available experimental and theoretical results.Keywords: DFT, GGA, LDA, properties structurales, ThC, ThN
Procedia PDF Downloads 924590 Temperature Coefficients of the Refractive Index for Ge Film
Authors: Lingmao Xu, Hui Zhou
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Ge film is widely used in infrared optical systems. Because of the special requirements of space application, it is usually used in low temperature. The refractive index of Ge film is always changed with the temperature which has a great effect on the manufacture of high precision infrared optical film. Specimens of Ge single film were deposited at ZnSe substrates by EB-PVD method. During temperature range 80K ~ 300K, the transmittance of Ge single film within 2 ~ 15 μm were measured every 20K by PerkinElmer FTIR cryogenic testing system. By the full spectrum inversion method fitting, the relationship between refractive index and wavelength within 2 ~ 12μm at different temperatures was received. It can be seen the relationship consistent with the formula Cauchy, which can be fitted. Then the relationship between refractive index of the Ge film and temperature/wavelength was obtained by fitting method based on formula Cauchy. Finally, the designed value obtained by the formula and the measured spectrum were compared to verify the accuracy of the formula.Keywords: infrared optical film, low temperature, thermal refractive coefficient, Ge film
Procedia PDF Downloads 2904589 The Response of Optical Properties to Temperature in Three-Layer Micro Device Under Influence of Casimir Force
Authors: Motahare Aali, Fatemeh Tajik
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Here, we investigate the sensitivity the Casimir force and consequently dynamical actuation of a three-layer microswitch to some ambient conditions. In fact, we have considered the effect of optical properties on the stable operation of the microswitch for both good (e.g. metals) and poor conductors via a three layer Casimir oscillator. Indeed, gold (Au) has been chosen as a good conductor which is widely used for Casimir force measurements, and highly doped conductive silicon carbide (SiC) has been considered as a poor conductor which is a promising material for device operating under harsh environments. Also, the intervening stratum is considered ethanol or water. It is also supposed that the microswitches are frictionless and autonomous. Using reduction factor diagrams and bifurcation curves, it has been shown how performance of the microswitches is sensitive to temperature and intervening stratum, moreover it is investigated how the conductivity of the components can affect this sensitivity.Keywords: Casimir force, optical properties, Lifshitz theory, dielectric function
Procedia PDF Downloads 854588 Estimations of Spectral Dependence of Tropospheric Aerosol Single Scattering Albedo in Sukhothai, Thailand
Authors: Siriluk Ruangrungrote
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Analyses of available data from MFR-7 measurement were performed and discussed on the study of tropospheric aerosol and its consequence in Thailand. Since, ASSA (w) is one of the most important parameters for a determination of aerosol effect on radioactive forcing. Here the estimation of w was directly determined in terms of the ratio of aerosol scattering optical depth to aerosol extinction optical depth (ωscat/ωext) without any utilization of aerosol computer code models. This is of benefit for providing the elimination of uncertainty causing by the modeling assumptions and the estimation of actual aerosol input data. Diurnal w of 5 cloudless-days in winter and early summer at 5 distinct wavelengths of 415, 500, 615, 673 and 870 nm with the consideration of Rayleigh scattering and atmospheric column NO2 and Ozone contents were investigated, respectively. Besides, the tendency of spectral dependence of ω representing two seasons was observed. The characteristic of spectral results reveals that during wintertime the atmosphere of the inland rural vicinity for the period of measurement possibly dominated with a lesser amount of soil dust aerosols loading than one in early summer. Hence, the major aerosol loading particularly in summer was subject to a mixture of both soil dust and biomass burning aerosols.Keywords: aerosol scattering optical depth, aerosol extinction optical depth, biomass burning aerosol, soil dust aerosol
Procedia PDF Downloads 4014587 Geothermal Prospect Prediction at Mt. Ciremai Using Fault and Fracture Density Method
Authors: Rifqi Alfadhillah Sentosa, Hasbi Fikru Syabi, Stephen
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West Java is a province in Indonesia which has a number of volcanoes. One of those volcanoes is Mt. Ciremai, located administratively at Kuningan and Majalengka District, and is known for its significant geothermal potential in Java Island. This research aims to assume geothermal prospects at Mt. Ciremai using Fault and Fracture Density (FFD) Method, which is correlated to the geochemistry of geothermal manifestations around the mountain. This FFD method is using SRTM data to draw lineaments, which are assumed associated with fractures and faults in the research area. These faults and fractures were assumed as the paths for reservoir fluids to reached surface as geothermal manifestations. The goal of this method is to analyze the density of those lineaments found in the research area. Based on this FFD Method, it is known that area with high density of lineaments located on Mt. Kromong at the northern side of Mt. Ciremai. This prospect area is proven by its higher geothermometer values compared to geothermometer values calculated at the south area of Mt. Ciremai.Keywords: geothermal prospect, fault and fracture density, Mt. Ciremai, surface manifestation
Procedia PDF Downloads 3554586 Dynamic Foot Pressure Measurement System Using Optical Sensors
Authors: Tanapon Keatsamarn, Chuchart Pintavirooj
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Foot pressure measurement provides necessary information for diagnosis diseases, foot insole design, disorder prevention and other application. In this paper, dynamic foot pressure measurement is presented for pressure measuring with high resolution and accuracy. The dynamic foot pressure measurement system consists of hardware and software system. The hardware system uses a transparent acrylic plate and uses steel as the base. The glossy white paper is placed on the top of the transparent acrylic plate and covering with a black acrylic on the system to block external light. Lighting from LED strip entering around the transparent acrylic plate. The optical sensors, the digital cameras, are underneath the acrylic plate facing upwards. They have connected with software system to process and record foot pressure video in avi file. Visual Studio 2017 is used for software system using OpenCV library.Keywords: foot, foot pressure, image processing, optical sensors
Procedia PDF Downloads 2404585 Historical Landscape Affects Present Tree Density in Paddy Field
Authors: Ha T. Pham, Shuichi Miyagawa
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Ongoing landscape transformation is one of the major causes behind disappearance of traditional landscapes, and lead to species and resource loss. Tree in paddy fields in the northeast of Thailand is one of those traditional landscapes. Using three different historical time layers, we acknowledged the severe deforestation and rapid urbanization happened in the region. Despite the general thinking of decline in tree density as consequences, the heterogeneous trend of changes in total tree density in three studied landscapes denied the hypothesis that number of trees in paddy field depend on the length of land use practice. On the other hand, due to selection of planting new trees on levees, existence of trees in paddy field are now rely on their values for human use. Besides, changes in land use and landscape structure had a significant impact on decision of which tree density level is considered as suitable for the landscape.Keywords: aerial photographs, land use change, traditional landscape, tree in paddy fields
Procedia PDF Downloads 4124584 Modelling of Silicon Solar Cell with Anti-reflecting Coating
Authors: Ankita Gaur, Mouli Karmakar, Shyam
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In this study, a silicon solar cell has been modeled and analyzed to enhance its electrical performance by improving the optical properties using an antireflecting coating (ARC). The dynamic optical reflectance, transmittance along with the net transmissivity absorptivity product of each layer are assessed as per the diurnal variation of the angle of incidence using MATLAB 2019. The model is tested with various Anti-Reflective coatings and the performance has also been compared with uncoated cells. ARC improves the optical transmittance of the photon. Higher transmittance of ⁓96.57% with lowest reflectance of ⁓ 1.74% at 12.00 hours was obtained with MgF₂ coated silicon cells. The electrical efficiency of the configured solar cell was evaluated for a composite climate of New Delhi, India, for all weather conditions. The annual electricity generation for Anti-reflective coated and uncoated crystalline silicon PV Module was observed to be 103.14 KWh and 99.51 KWh, respectively.Keywords: antireflecting coating, electrical efficiency, reflectance, solar cell, transmittance
Procedia PDF Downloads 1484583 New Method for Determining the Distribution of Birefringence and Linear Dichroism in Polymer Materials Based on Polarization-Holographic Grating
Authors: Barbara Kilosanidze, George Kakauridze, Levan Nadareishvili, Yuri Mshvenieradze
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A new method for determining the distribution of birefringence and linear dichroism in optical polymer materials is presented. The method is based on the use of polarization-holographic diffraction grating that forms an orthogonal circular basis in the process of diffraction of probing laser beam on the grating. The intensities ratio of the orders of diffraction on this grating enables the value of birefringence and linear dichroism in the sample to be determined. The distribution of birefringence in the sample is determined by scanning with a circularly polarized beam with a wavelength far from the absorption band of the material. If the scanning is carried out by probing beam with the wavelength near to a maximum of the absorption band of the chromophore then the distribution of linear dichroism can be determined. An appropriate theoretical model of this method is presented. A laboratory setup was created for the proposed method. An optical scheme of the laboratory setup is presented. The results of measurement in polymer films with two-dimensional gradient distribution of birefringence and linear dichroism are discussed.Keywords: birefringence, linear dichroism, graded oriented polymers, optical polymers, optical anisotropy, polarization-holographic grating
Procedia PDF Downloads 4284582 The Use of Optical-Radar Remotely-Sensed Data for Characterizing Geomorphic, Structural and Hydrologic Features and Modeling Groundwater Prospective Zones in Arid Zones
Authors: Mohamed Abdelkareem
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Remote sensing data contributed on predicting the prospective areas of water resources. Integration of microwave and multispectral data along with climatic, hydrologic, and geological data has been used here. In this article, Sentinel-2, Landsat-8 Operational Land Imager (OLI), Shuttle Radar Topography Mission (SRTM), Tropical Rainfall Measuring Mission (TRMM), and Advanced Land Observing Satellite (ALOS) Phased Array Type L‐band Synthetic Aperture Radar (PALSAR) data were utilized to identify the geological, hydrologic and structural features of Wadi Asyuti which represents a defunct tributary of the Nile basin, in the eastern Sahara. The image transformation of Sentinel-2 and Landsat-8 data allowed characterizing the different varieties of rock units. Integration of microwave remotely-sensed data and GIS techniques provided information on physical characteristics of catchments and rainfall zones that are of a crucial role for mapping groundwater prospective zones. A fused Landsat-8 OLI and ALOS/PALSAR data improved the structural elements that difficult to reveal using optical data. Lineament extraction and interpretation indicated that the area is clearly shaped by the NE-SW graben that is cut by NW-SE trend. Such structures allowed the accumulation of thick sediments in the downstream area. Processing of recent OLI data acquired on March 15, 2014, verified the flood potential maps and offered the opportunity to extract the extent of the flooding zone of the recent flash flood event (March 9, 2014), as well as revealed infiltration characteristics. Several layers including geology, slope, topography, drainage density, lineament density, soil characteristics, rainfall, and morphometric characteristics were combined after assigning a weight for each using a GIS-based knowledge-driven approach. The results revealed that the predicted groundwater potential zones (GPZs) can be arranged into six distinctive groups, depending on their probability for groundwater, namely very low, low, moderate, high very, high, and excellent. Field and well data validated the delineated zones.Keywords: GIS, remote sensing, groundwater, Egypt
Procedia PDF Downloads 914581 Density Determination by Dilution for Extra Heavy Oil Residues Obtained Using Molecular Distillation and Supercritical Fluid Extraction as Upgrading and Refining Process
Authors: Oscar Corredor, Alexander Guzman, Adan Leon
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Density is a bulk physical property that indicates the quality of a petroleum fraction. It is also a useful property to estimate various physicochemical properties of fraction and petroleum fluids; however, the determination of density of extra heavy residual (EHR) fractions by standard methodologies, (ASTM D70) shows limitations for samples with higher densities than 1.0879 g/cm3. For this reason, a dilution methodology was developed in order to determinate density for those particular fractions, 87 (EHR) fractions were obtained as products of the fractionation of Colombian typical Vacuum Distillation Residual Fractions using molecular distillation (MD) and extraction with Solvent N-hexane in Supercritical Conditions (SFEF) pilot plants. The proposed methodology showed reliable results that can be demonstrated with the standard deviation of repeatability and reproducibility values of 0.0031 and 0.0061 g/ml respectively. In the same way, it was possible to determine densities in fractions EHR up to 1.1647g/cm3 and °API values obtained were ten times less than the water reference value.Keywords: API, density, vacuum residual, molecular distillation, supercritical fluid extraction
Procedia PDF Downloads 2614580 Investigation on Properties and Applications of Graphene as Single Layer of Carbon Atoms
Authors: Ali Ashjaran
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Graphene is undoubtedly emerging as one of the most promising materials because of its unique combination of superb properties, which opens a way for its exploitation in a wide spectrum of applications ranging from electronics to optics, sensors, and biodevices. In addition, Graphene-based nanomaterials have many promising applications in energy-related areas. Graphene a single layer of carbon atoms, combines several exceptional properties, which makes it uniquely suited as a coating material: transparency, excellent mechanical stability, low chemical reactivity, Optical, impermeability to most gases, flexibility, and very high thermal and electrical conductivity. Graphene is a material that can be utilized in numerous disciplines including, but not limited to: bioengineering, composite materials, energy technology and nanotechnology, biological engineering, optical electronics, ultrafiltration, photovoltaic cells. This review aims to provide an overiew of graphene structure, properties and some applications.Keywords: graphene, carbon, anti corrosion, optical and electrical properties, sensors
Procedia PDF Downloads 2724579 Enhanced Optical and Electrical Properties of P-Type AgBiS₂ Energy Harvesting Materials as an Absorber of Solar Cell by Copper Doping
Authors: Yasaman Tabari-Saadi, Kaiwen Sun, Jialiang Huang, Martin Green, Xiaojing Hao
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Optical and electrical properties of p-type AgBiS₂ absorber material have been improved by copper doping on silver sites. X-Ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analysis suggest that complete solid solutions of Ag₁₋ₓCuₓBiS₂ thin film have been formed. The carrier concentration of pure AgBiS₂ thin film deposited by the chemical process is 4.5*E+14 cm⁻³, and copper doping leads to the improved carrier concentration despite the semiconductor AgBiS₂ remains p-type semiconductor. Copper doping directly changed the absorption coefficient and increased the optical band gap (~1.5eV), which makes it a promising absorber for thin-film solar cell applications.Keywords: copper doped, AgBiS₂, thin-film solar cell, carrier concentration, p-type semiconductor
Procedia PDF Downloads 1164578 Synthesis, Structural, Spectroscopic and Nonlinear Optical Properties of New Picolinate Complex of Manganese (II) Ion
Authors: Ömer Tamer, Davut Avcı, Yusuf Atalay
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Novel picolinate complex of manganese(II) ion, [Mn(pic)2] [pic: picolinate or 2-pyridinecarboxylate], was prepared and fully characterized by single crystal X-ray structure determination. The manganese(II) complex was characterized by FT-IR, FT-Raman and UV–Vis spectroscopic techniques. The C=O, C=N and C=C stretching vibrations were found to be strong and simultaneously active in IR and spectra. In order to support these experimental techniques, density functional theory (DFT) calculations were performed at Gaussian 09W. Although the supramolecular interactions have some influences on the molecular geometry in solid state phase, the calculated data show that the predicted geometries can reproduce the structural parameters. The molecular modeling and calculations of IR, Raman and UV-vis spectra were performed by using DFT levels. Nonlinear optical (NLO) properties of synthesized complex were evaluated by the determining of dipole moment (µ), polarizability (α) and hyperpolarizability (β). Obtained results demonstrated that the manganese(II) complex is a good candidate for NLO material. Stability of the molecule arising from hyperconjugative interactions and charge delocalization was analyzed using natural bond orbital (NBO) analysis. The highest occupied and the lowest unoccupied molecular orbitals (HOMO and LUMO) which is also known the frontier molecular orbitals were simulated, and obtained energy gap confirmed that charge transfer occurs within manganese(II) complex. Molecular electrostatic potential (MEP) for synthesized manganese(II) complex displays the electrophilic and nucleophilic regions. From MEP, the the most negative region is located over carboxyl O atoms while positive region is located over H atoms.Keywords: DFT, picolinate, IR, Raman, nonlinear optic
Procedia PDF Downloads 4944577 Application of Optical Method for Calcul of Deformed Object Samples
Authors: R. Daira
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The electronic speckle interferometry technique used to measure the deformations of scatterers process is based on the subtraction of interference patterns. A speckle image is first recorded before deformation of the object in the RAM of a computer, after a second deflection. The square of the difference between two images showing correlation fringes observable in real time directly on monitor. The interpretation these fringes to determine the deformation. In this paper, we present experimental results of deformation out of the plane of two samples in aluminum, electronic boards and stainless steel.Keywords: optical method, holography, interferometry, deformation
Procedia PDF Downloads 3974576 Investigation of Delivery of Triple Play Data in GE-PON Fiber to the Home Network
Authors: Ashima Anurag Sharma
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Optical fiber based networks can deliver performance that can support the increasing demands for high speed connections. One of the new technologies that have emerged in recent years is Passive Optical Networks. This research paper is targeted to show the simultaneous delivery of triple play service (data, voice, and video). The comparison between various data rates is presented. It is demonstrated that as we increase the data rate, number of users to be decreases due to increase in bit error rate.Keywords: BER, PON, TDMPON, GPON, CWDM, OLT, ONT
Procedia PDF Downloads 5204575 An Improved OCR Algorithm on Appearance Recognition of Electronic Components Based on Self-adaptation of Multifont Template
Authors: Zhu-Qing Jia, Tao Lin, Tong Zhou
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The recognition method of Optical Character Recognition has been expensively utilized, while it is rare to be employed specifically in recognition of electronic components. This paper suggests a high-effective algorithm on appearance identification of integrated circuit components based on the existing methods of character recognition, and analyze the pros and cons.Keywords: optical character recognition, fuzzy page identification, mutual correlation matrix, confidence self-adaptation
Procedia PDF Downloads 5314574 The Effect of Hydrogen on the Magnetic Properties of ZnO: A Density Functional Tight Binding Study
Authors: M. A. Lahmer, K. Guergouri
Abstract:
The ferromagnetic properties of carbon-doped ZnO (ZnO:CO) and hydrogenated carbon-doped ZnO (ZnO:CO+H) are investigated using the density functional tight binding (DFTB) method. Our results reveal that CO-doped ZnO is a ferromagnetic material with a magnetic moment of 1.3 μB per carbon atom. The presence of hydrogen in the material in the form of CO-H complex decreases the total magnetism of the material without suppressing ferromagnetism. However, the system in this case becomes quickly antiferromagnetic when the C-C separation distance was increased.Keywords: ZnO, carbon, hydrogen, ferromagnetism, density functional tight binding
Procedia PDF Downloads 2794573 Investigation on Electronic and Magnetic Properties of Transition Metals Doped Zinc Selenide
Authors: S. Bentata, W. Benstaali, A. Abbad, H. A. Bentounes, B. Bouadjemi
Abstract:
The full potential linear augmented plane wave (FPLAPW) based on density-functional theory (DFT) is employed to study the electronic, magnetic and optical properties of some transition metals doped ZnSe. Calculations are carried out by varying the doped atoms. Four 3D transition elements were used as a dopant: Cr, Mn, Co and Cu in order to induce spin polarization. Our results show that, Mn and Cu-doped ZnSe could be used in spintronic devices only if additional dopants are introduced, on the contrary, transition elements showing delocalized quality such as Cr, and Co doped ZnSe might be promising candidates for application in spintronic.Keywords: spin-up, spin-down, magnetic properties, transition metal, composite materials
Procedia PDF Downloads 2644572 Surveillance of Super-Extended Objects: Bimodal Approach
Authors: Andrey V. Timofeev, Dmitry Egorov
Abstract:
This paper describes an effective solution to the task of a remote monitoring of super-extended objects (oil and gas pipeline, railways, national frontier). The suggested solution is based on the principle of simultaneously monitoring of seismoacoustic and optical/infrared physical fields. The principle of simultaneous monitoring of those fields is not new but in contrast to the known solutions the suggested approach allows to control super-extended objects with very limited operational costs. So-called C-OTDR (Coherent Optical Time Domain Reflectometer) systems are used to monitor the seismoacoustic field. Far-CCTV systems are used to monitor the optical/infrared field. A simultaneous data processing provided by both systems allows effectively detecting and classifying target activities, which appear in the monitored objects vicinity. The results of practical usage had shown high effectiveness of the suggested approach.Keywords: C-OTDR monitoring system, bimodal processing, LPboost, SVM
Procedia PDF Downloads 463