Search results for: multi-label logarithmic loss
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3509

Search results for: multi-label logarithmic loss

3299 Application of UV-C Irradiation on Quality and Textural Properties of Button Mushrooms

Authors: M. Ghasemi-Varnamkhasti, S. H. Yoosefian. A. Mohammad- Razdari

Abstract:

The effect of 1.0 kJ/m2 Ultraviolet-C (UV-C) light on pH, weight loss, color, and firmness of button mushroom (Agaricus bisporus) tissues during 21-days storage at 4 ºC was studied. UV-C irradiation enhanced pH, weight, color parameters, and firmness of mushroom during storage compared to control treatment. However, application of 1.0 kJ/m2 UV-C treatment could effectively induce the increase of weight loss, firmness, and pH to 14.53%, 49.82%, and 10.39%, respectively. These results suggest that the application of UV-C irradiation could be an effective method to maintain the postharvest quality of mushrooms.

Keywords: mushroom, polyethylene film, quality, UV-c irradiation

Procedia PDF Downloads 295
3298 Case Studies in Three Domains of Learning: Cognitive, Affective, Psychomotor

Authors: Zeinabsadat Haghshenas

Abstract:

Bloom’s Taxonomy has been changed during the years. The idea of this writing is about the revision that has happened in both facts and terms. It also contains case studies of using cognitive Bloom’s taxonomy in teaching geometric solids to the secondary school students, affective objectives in a creative workshop for adults and psychomotor objectives in fixing a malfunctioned refrigerator lamp. There is also pointed to the important role of classification objectives in adult education as a way to prevent memory loss.

Keywords: adult education, affective domain, cognitive domain, memory loss, psychomotor domain

Procedia PDF Downloads 466
3297 Investigation of the Flow in Impeller Sidewall Gap of a Centrifugal Pump Using CFD

Authors: Mohammadreza DaqiqShirazi, Rouhollah Torabi, Alireza Riasi, Ahmad Nourbakhsh

Abstract:

In this paper, the flow in a sidewall gap of an impeller which belongs to a centrifugal pump is studied using numerical method. The flow in sidewall gap forms internal leakage and is the source of “disk friction loss” which is the most important cause of reduced efficiency in low specific speed centrifugal pumps. Simulation is done using CFX software and a high quality mesh, therefore the modeling error has been reduced. Navier-Stokes equations have been solved for this domain. In order to predict the turbulence effects the SST model has been employed.

Keywords: numerical study, centrifugal pumps, disk friction loss, sidewall gap

Procedia PDF Downloads 529
3296 The Use of Empirical Models to Estimate Soil Erosion in Arid Ecosystems and the Importance of Native Vegetation

Authors: Meshal M. Abdullah, Rusty A. Feagin, Layla Musawi

Abstract:

When humans mismanage arid landscapes, soil erosion can become a primary mechanism that leads to desertification. This study focuses on applying soil erosion models to a disturbed landscape in Umm Nigga, Kuwait, and identifying its predicted change under restoration plans, The northern portion of Umm Nigga, containing both coastal and desert ecosystems, falls within the boundaries of the Demilitarized Zone (DMZ) adjacent to Iraq, and has been fenced off to restrict public access since 1994. The central objective of this project was to utilize GIS and remote sensing to compare the MPSIAC (Modified Pacific South West Inter Agency Committee), EMP (Erosion Potential Method), and USLE (Universal Soil Loss Equation) soil erosion models and determine their applicability for arid regions such as Kuwait. Spatial analysis was used to develop the necessary datasets for factors such as soil characteristics, vegetation cover, runoff, climate, and topography. Results showed that the MPSIAC and EMP models produced a similar spatial distribution of erosion, though the MPSIAC had more variability. For the MPSIAC model, approximately 45% of the land surface ranged from moderate to high soil loss, while 35% ranged from moderate to high for the EMP model. The USLE model had contrasting results and a different spatial distribution of the soil loss, with 25% of area ranging from moderate to high erosion, and 75% ranging from low to very low. We concluded that MPSIAC and EMP were the most suitable models for arid regions in general, with the MPSIAC model best. We then applied the MPSIAC model to identify the amount of soil loss between coastal and desert areas, and fenced and unfenced sites. In the desert area, soil loss was different between fenced and unfenced sites. In these desert fenced sites, 88% of the surface was covered with vegetation and soil loss was very low, while at the desert unfenced sites it was 3% and correspondingly higher. In the coastal areas, the amount of soil loss was nearly similar between fenced and unfenced sites. These results implied that vegetation cover played an important role in reducing soil erosion, and that fencing is much more important in the desert ecosystems to protect against overgrazing. When applying the MPSIAC model predictively, we found that vegetation cover could be increased from 3% to 37% in unfenced areas, and soil erosion could then decrease by 39%. We conclude that the MPSIAC model is best to predict soil erosion for arid regions such as Kuwait.

Keywords: soil erosion, GIS, modified pacific South west inter agency committee model (MPSIAC), erosion potential method (EMP), Universal soil loss equation (USLE)

Procedia PDF Downloads 297
3295 A Wall Law for Two-Phase Turbulent Boundary Layers

Authors: Dhahri Maher, Aouinet Hana

Abstract:

The presence of bubbles in the boundary layer introduces corrections into the log law, which must be taken into account. In this work, a logarithmic wall law was presented for bubbly two phase flows. The wall law presented in this work was based on the postulation of additional turbulent viscosity associated with bubble wakes in the boundary layer. The presented wall law contained empirical constant accounting both for shear induced turbulence interaction and for non-linearity of bubble. This constant was deduced from experimental data. The wall friction prediction achieved with the wall law was compared to the experimental data, in the case of a turbulent boundary layer developing on a vertical flat plate in the presence of millimetric bubbles. A very good agreement between experimental and numerical wall friction prediction was verified. The agreement was especially noticeable for the low void fraction when bubble induced turbulence plays a significant role.

Keywords: bubbly flows, log law, boundary layer, CFD

Procedia PDF Downloads 278
3294 Basic Calibration and Normalization Techniques for Time Domain Reflectometry Measurements

Authors: Shagufta Tabassum

Abstract:

The study of dielectric properties in a binary mixture of liquids is very useful to understand the liquid structure, molecular interaction, dynamics, and kinematics of the mixture. Time-domain reflectometry (TDR) is a powerful tool for studying the cooperation and molecular dynamics of the H-bonded system. In this paper, we discuss the basic calibration and normalization procedure for time-domain reflectometry measurements. Our approach is to explain the different types of error occur during TDR measurements and how these errors can be eliminated or minimized.

Keywords: time domain reflectometry measurement techinque, cable and connector loss, oscilloscope loss, and normalization technique

Procedia PDF Downloads 206
3293 Effect of Monotonically Decreasing Parameters on Margin Softmax for Deep Face Recognition

Authors: Umair Rashid

Abstract:

Normally softmax loss is used as the supervision signal in face recognition (FR) system, and it boosts the separability of features. In the last two years, a number of techniques have been proposed by reformulating the original softmax loss to enhance the discriminating power of Deep Convolutional Neural Networks (DCNNs) for FR system. To learn angularly discriminative features Cosine-Margin based softmax has been adjusted as monotonically decreasing angular function, that is the main challenge for angular based softmax. On that issue, we propose monotonically decreasing element for Cosine-Margin based softmax and also, we discussed the effect of different monotonically decreasing parameters on angular Margin softmax for FR system. We train the model on publicly available dataset CASIA- WebFace via our proposed monotonically decreasing parameters for cosine function and the tests on YouTube Faces (YTF, Labeled Face in the Wild (LFW), VGGFace1 and VGGFace2 attain the state-of-the-art performance.

Keywords: deep convolutional neural networks, cosine margin face recognition, softmax loss, monotonically decreasing parameter

Procedia PDF Downloads 101
3292 Performance Analysis of a Planar Membrane Humidifier for PEM Fuel Cell

Authors: Yu-Hsuan Chang, Jian-Hao Su, Chen-Yu Chen, Wei-Mon Yan

Abstract:

In this work, the experimental measurement was applied to examine the membrane type and flow field design on the performance of a planar membrane humidifier. The performance indexes were used to evaluate the planar membrane humidifier. The performance indexes of the membrane humidifier include the dew point approach temperature (DPAT), water recovery ratio (WRR), water flux (J) and pressure loss (P). The experiments contain mainly three parts. In the first part, a single membrane humidifier was tested using different flow field under different dry-inlet temperatures. The measured results show that the dew point approach temperature decreases with increasing the depth of flow channel at the same width of flow channel. However, the WRR and J reduce with an increase in the dry air-inlet temperature. The pressure loss tests indicate that pressure loss decreases with increasing the hydraulic diameter of flow channel, resulting from an increase in Darcy friction. Owing to the comparison of humidifier performances and pressure losses, the flow channel of width W=1 and height H=1.5 was selected as the channel design of the multi-membrane humidifier in the second part of experiment. In the second part, the multi-membrane humidifier was used to evaluate the humidification performance under different relative humidity and flow rates. The measurement results indicate that the humidifier at both lower temperature and relative humidity of inlet dry air have higher DPAT but lower J and WRR. In addition, the counter flow approach has better mass and heat transfer performance than the parallel flow approach. Moreover, the effects of dry air temperature, relative humidity and humidification approach are not significant to the pressure loss in the planar membrane humidifier. For the third part, different membranes were tested in this work in order to find out which kind membrane is appropriate for humidifier.

Keywords: water management, planar membrane humidifier, heat and mass transfer, pressure loss, PEM fuel cell

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3291 3D Simulation of Orthodontic Tooth Movement in the Presence of Horizontal Bone Loss

Authors: Azin Zargham, Gholamreza Rouhi, Allahyar Geramy

Abstract:

One of the most prevalent types of alveolar bone loss is horizontal bone loss (HBL) in which the bone height around teeth is reduced homogenously. In the presence of HBL the magnitudes of forces during orthodontic treatment should be altered according to the degree of HBL, in a way that without further bone loss, desired tooth movement can be obtained. In order to investigate the appropriate orthodontic force system in the presence of HBL, a three-dimensional numerical model capable of the simulation of orthodontic tooth movement was developed. The main goal of this research was to evaluate the effect of different degrees of HBL on a long-term orthodontic tooth movement. Moreover, the effect of different force magnitudes on orthodontic tooth movement in the presence of HBL was studied. Five three-dimensional finite element models of a maxillary lateral incisor with 0 mm, 1.5 mm, 3 mm, 4.5 mm and 6 mm of HBL were constructed. The long-term orthodontic tooth tipping movements were attained during a 4-weeks period in an iterative process through the external remodeling of the alveolar bone based on strains in periodontal ligament as the bone remodeling mechanical stimulus. To obtain long-term orthodontic tooth movement in each iteration, first the strains in periodontal ligament under a 1-N tipping force were calculated using finite element analysis. Then, bone remodeling and the subsequent tooth movement were computed in a post-processing software using a custom written program. Incisal edge, cervical, and apical area displacement in the models with different alveolar bone heights (0, 1.5, 3, 4.5, 6 mm bone loss) in response to a 1-N tipping force were calculated. Maximum tooth displacement was found to be 2.65 mm at the top of the crown of the model with a 6 mm bone loss. Minimum tooth displacement was 0.45 mm at the cervical level of the model with a normal bone support. Tooth tipping degrees of models in response to different tipping force magnitudes were also calculated for models with different degrees of HBL. Degrees of tipping tooth movement increased as force level was increased. This increase was more prominent in the models with smaller degrees of HBL. By using finite element method and bone remodeling theories, this study indicated that in the presence of HBL, under the same load, long-term orthodontic tooth movement will increase. The simulation also revealed that even though tooth movement increases with increasing the force, this increase was only prominent in the models with smaller degrees of HBL, and tooth models with greater degrees of HBL will be less affected by the magnitude of an orthodontic force. Based on our results, the applied force magnitude must be reduced in proportion of degree of HBL.

Keywords: bone remodeling, finite element method, horizontal bone loss, orthodontic tooth movement.

Procedia PDF Downloads 342
3290 Performance Analysis of Compression Socks Strips

Authors: Hafiz Faisal Siddique, Adnan Ahmed Mazari, Antonin Havelka

Abstract:

Compression socks are highly recommended textile garment for pressure exertion on the lower part of leg. The extent of compression that a patient can easily manage depends on stage (limb size and shape) of venous disease and his activities (mobility, age). Due to dynamic mechanical influence, the socks destroy their extent of pressure exertion around the leg. The main aim of this research is to investigate how the performance of compression socks is deteriorated due to expected induced wearing mechanical impacts. Wearing mechanical impacts influence the durability parameter i.e. tensile energy loss. For tensile energy loss, cut-strip samples were interacted to constant rate of loading and un-loading, cyclic-loading upto 15th cycles for ±5mm extension (considering muscles expansion and relaxation) and were dwelled (stayed) for 3 minutes at 25%, 50% and 75% extension levels, simultaneously. Statistical validation of tensile energy loss was performed by introducing measures of correlation, p-value (≤ 0.05), R-square values using MINITAB 17 software.

Keywords: compression socks, loading and unloading, 15th cyclic loading, Dwell time effect

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3289 Advocacy for Increasing Health Care Budget in Parepare City with DALY Approach: Case Study on Improving Public Health Insurance Budget

Authors: Kasman, Darmawansyah, Alimin Maidin, Amran Razak

Abstract:

Background: In decentralization, advocacy is needed to increase the health budget in Parepare District. One of the advocacy methods recommended by the World Bank is the economic loss approach. Methods: This research is observational in the field of health economics that contributes directly to the magnitude of the economic loss of the community and the government and provides advocacy to the executive and legislative to see the harm it causes. Results: The research results show the amount of direct cost, which consists of household expenditure for transport Rp.295,865,500. Indirect Cost of YLD of Rp.14.688.000, and YLL of Rp.28.986.336.00, so the amount of DALY is Rp.43.674.336.000. The total economic loss of Rp.43.970.201.500. These huge economic losses can be prevented by increasing the allocation of health budgets for promotive and preventive efforts and expanding the coverage of health insurance for the community. Conclusion: There is a need to advocate the executive and legislative about the importance of guarantee on public health financing by conducting studies in terms of economic losses so that all strategic alliances believe that health is an investment.

Keywords: advocacy, economic lost, health insurance, economic losses

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3288 Error Correction Method for 2D Ultra-Wideband Indoor Wireless Positioning System Using Logarithmic Error Model

Authors: Phornpat Chewasoonthorn, Surat Kwanmuang

Abstract:

Indoor positioning technologies have been evolved rapidly. They augment the Global Positioning System (GPS) which requires line-of-sight to the sky to track the location of people or objects. This study developed an error correction method for an indoor real-time location system (RTLS) based on an ultra-wideband (UWB) sensor from Decawave. Multiple stationary nodes (anchor) were installed throughout the workspace. The distance between stationary and moving nodes (tag) can be measured using a two-way-ranging (TWR) scheme. The result has shown that the uncorrected ranging error from the sensor system can be as large as 1 m. To reduce ranging error and thus increase positioning accuracy, This study purposes an online correction algorithm using the Kalman filter. The results from experiments have shown that the system can reduce ranging error down to 5 cm.

Keywords: indoor positioning, ultra-wideband, error correction, Kalman filter

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3287 Compact Low Loss Design of SOI 1x2 Y-Branch Optical Power Splitter with S-Bend Waveguide and Study on the Variation of Transmitted Power with Various Waveguide Parameters

Authors: Nagaraju Pendam, C. P. Vardhani

Abstract:

A simple technology–compatible design of silicon-on-insulator based 1×2 optical power splitter is proposed. For developing large area Opto-electronic Silicon-on-Insulator (SOI) devices, the power splitter is a key passive device. The SOI rib- waveguide dimensions (height, width, and etching depth, refractive indices, length of waveguide) leading simultaneously to single mode propagation. In this paper a low loss optical power splitter is designed by using R Soft cad tool and simulated by Beam propagation method, here s-bend waveguides proposed. We concentrate changing the refractive index difference, branching angle, width of the waveguide, free space wavelength of the waveguide and observing transmitted power, effective refractive index in the designed waveguide, and choosing the best simulated results to be fabricated on silicon-on insulator platform. In this design 1550 nm free spacing are used.

Keywords: beam propagation method, insertion loss, optical power splitter, rib waveguide, transmitted power

Procedia PDF Downloads 663
3286 Study of the Tribological Behavior of a Pin on Disc Type of Contact

Authors: S. Djebali, S. Larbi, A. Bilek

Abstract:

The present work aims at contributing to the study of the complex phenomenon of wear of pin on disc contact in dry sliding friction between two material couples (bronze/steel and unsaturated polyester virgin and charged with graphite powder/steel). The work consists of the determination of the coefficient of friction, the study of the influence of the tribological parameters on this coefficient and the determination of the mass loss and the wear rate of the pin. This study is also widened to the highlighting of the influence of the addition of graphite powder on the tribological properties of the polymer constituting the pin. The experiments are carried out on a pin-disc type tribometer that we have designed and manufactured. Tests are conducted according to the standards DIN 50321 and DIN EN 50324. The discs are made of annealed XC48 steel and quenched and tempered XC48 steel. The main results are described here after. The increase of the normal load and the sliding speed causes the increase of the friction coefficient, whereas the increase of the percentage of graphite and the hardness of the disc surface contributes to its reduction. The mass loss also increases with the normal load. The influence of the normal load on the friction coefficient is more significant than that of the sliding speed. The effect of the sliding speed decreases for large speed values. The increase of the amount of graphite powder leads to a decrease of the coefficient of friction, the mass loss and the wear rate. The addition of graphite to the UP resin is beneficial; it plays the role of solid lubricant.

Keywords: bronze, friction coefficient, graphite, mass loss, polyester, steel, wear rate

Procedia PDF Downloads 345
3285 Changes in the Quality of Life of Turkish Patients with Trauma-Related Phthisis Bulbi

Authors: Titap Yazicioglu

Abstract:

Purpose: Losing an eye due to trauma is a challenging situation that reduces the quality of life by causing physical, cosmetic, and serious psychological problems. This study aimed to evaluate the effect of aesthetic rehabilitation on the change in psychological status and quality of life of patients with eye loss resulting in phthisis bulbi. Materials and Methods: The files of 25 males and 15 females with an average age of 27.5 years who had trauma-related phthisic eye and had applied to the Department of Ophthalmology at the Dr. Lütfi Kırdar Kartal Education and Research Hospital, Istanbul, Turkey, for aesthetic rehabilitation during the years 2015-19 were retrospectively analyzed. The Beck Depression Inventory (BDI), Beck Anxiety Scale(BAS), and Short Form 36 quality-of-life survey (SF-36) were used to collect data on admission and one-year follow-up. Results: Of the patients reviewed, 65% stated that eye loss had caused their avoidance of family and social environments; 30% had moderate anxiety and depression. The post-operative sub-dimension scores of general health, emotional role function, and physical and social functions were statistically significant (p = 0.001; p<0.01), but the variations in the sub-dimension scores of vitality, mental health, and total physical health were not (p>0.05). Conclusion: Lossing an eye is a traumatic event that can affect all aspects of a person’s social and professional life. A patient who has suffered from the psychological damage of physical loss of eye needs a prosthesis that can give the desired function and appearance in different aspects of life.

Keywords: eye loss, phthisis bulbi, quality of life, psychological trauma

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3284 Hearing Conservation Aspects of Soldier’s Exposure to Harmfull Noise within Military Armored Vehicles

Authors: Fink Nir

Abstract:

Soldiers within armored vehicles are exposed to continuous noise reaching levels as high as 120 dB. The use of hearing protection devices (HPD) may attenuate noise by as 25 dB, but attenuated noise reaching the ear is still harmful and may result in hearing loss. Hearing conservation programs in the military suggest methods to manage the harmful effects of noise. These include noise absorption within vehicles, evaluating HPD's performance, limiting time exposure, and providing guidance.

Keywords: armored vehicle noise, hearing loss, hearing protection devices, military noise, noise attenuation

Procedia PDF Downloads 146
3283 The Use of Hearing Protection Devices and Hearing Loss in Steel Industry Workers in Samut Prakan Province, Thailand

Authors: Petcharat Kerdonfag, Surasak Taneepanichskul, Winai Wadwongtham

Abstract:

Background: Although there have not been effective treatments for Noise Induced Hearing Loss (NIHL), it can be definitely preventable with promoting the use of Hearing Protection devices (HPDs) among workers who have been exposed to excessive noise for a long period. Objectives: The objectives of this study were to explore the use of HPDs among steel industrial workers in the high noise level zone in Samut Prakan province, Thailand and to examine the relationships of the HPDs use and hearing loss. Materials and Methods: In this cross-sectional study, eligible ninety-three participants were recruited in the designated zone of higher noise (> 85dBA) of two factories, using simple random sampling. The use of HPDs was gathered by the self-record form, examined and confirmed by the researcher team. Hearing loss was assessed by the audiometric screening at the regional Samut Prakan hospital. If an average threshold level exceeds 25 dBA at high frequency (4 and 6 Hz) in each ear, participants would be lost of hearing. Data were collected from October to December, 2016. All participants were examined by the same examiners for the validity. An Audiometric testing was performed with the participants who have been exposed to high noise levels at least 14 hours from workplace. Results: Sixty participants (64.5%) had secondary level of education. The average mean score of percent time of using HPDs was 60.5% (SD = 25.34). Sixty-seven participants (72.0%) had abnormal hearing which they have still needed to increase lower percent time of using HPDs (Mean = 37.01, SD = 23.81) than those having normal hearing (Mean = 45.77, SD = 28.44). However, there was no difference in the mean average of percent time of using HPDs between these two groups.Conclusion: The findings of this study have confirmed that the steel industrial workers still need to be motivated to use HPDs regularly. Future research should pay more attentions for creating a meaningful innovation to steel industrial workers.

Keywords: hearing protection devices, noise induced hearing loss, audiometric testing, steel industry

Procedia PDF Downloads 256
3282 Microbial Corrosion on Oil and Gas Facilities: A Case Study of Oil and Gas Facilities in the Niger-Delta

Authors: Frederick Otite Ighovojah

Abstract:

Corrosion in the oil and gas industries is one of the most common causes of failure. Such failure includes leaks in above-ground storage tanks (AGST). The involvement of microorganisms in the corrosion process in AGST systems is often ignored, and this outlines the need to investigate the effect of microbial corrosion in oil and gas facilities. This study's methodology comprised gathering generated water samples from a nearby AGST oil facility that was operating, which were then equally divided into two batch reactors, 1 and 2. Each batch reactor was filled with five prepared X60 coupons using sterilized forceps. To provide nutrients for the microorganisms in batch reactor 1 during the test period, 2g of NPK 15- 15-15 fertilizer was added on a weekly basis. To kill the microorganisms and significantly lower their concentration in the generated water, 5ml of dissolved ozone (a biocide) with a 0.5ppm concentration was added to batch reactor 2. The weight loss measurement (WLM) was used to evaluate for corrosion. Coupons were removed from each batch reactor, and weight loss was measured at every interval of 336 hrs for 2016 hrs. The overall results obtained indicated that coupons from the batch 1 reactor showed a higher corrosion rate and higher mass loss, and this was due to the metabolic production of an aggressive compound in the medium.

Keywords: AGST, microbial corrosion, reactor, X60 steel

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3281 Determination of Harmful Important Mite (ACARI) and Nematoda Species, Their Distribution and Their Control Possibility on Garlic and Onion Growing Areas in Turkey

Authors: Cihan Cilbircioğlu

Abstract:

Allium sativum L.(garlic) and Allium. cepa L. (onion) are the most common species of the Allium spp. and are produced at the very high rate all over the world. The yield loss caused by pests is the most important problem in the production of these crops. In the absence of control measures, yield loss would be around 35% on average. The yield loss sometimes depending on the pest species and population density can reach about 100%. Mites and nematodes are the most important pests of them. These pests that cause damage to A. sativum and A. cepa shows a wide range of taxonomic categories. The number of common pest mite and nematode species that cause damage to either A. sativum and A. cepa are over 20 species. In this study, detailed information on morphology, life cycle, management, and symptoms of the economically most important harmful important mite (acari) and nematode species of onion and garlic has been provided through careful survey of corresponding researches in Turkey and given information about new practices and approaches on their controls.

Keywords: onion, garlic, pest, acari, nematoda control methods, Turkey

Procedia PDF Downloads 487
3280 Simulation of Reflection Loss for Carbon and Nickel-Carbon Thin Films

Authors: M. Emami, R. Tarighi, R. Goodarzi

Abstract:

Maximal radar wave absorbing cannot be achieved by shaping alone. We have to focus on the parameters of absorbing materials such as permittivity, permeability, and thickness so that best absorbing according to our necessity can happen. The real and imaginary parts of the relative complex permittivity (εr' and εr") and permeability (µr' and µr") were obtained by simulation. The microwave absorbing property of carbon and Ni(C) is simulated in this study by MATLAB software; the simulation was in the frequency range between 2 to 12 GHz for carbon black (C), and carbon coated nickel (Ni(C)) with different thicknesses. In fact, we draw reflection loss (RL) for C and Ni-C via frequency. We have compared their absorption for 3-mm thickness and predicted for other thicknesses by using of electromagnetic wave transmission theory. The results showed that reflection loss position changes in low frequency with increasing of thickness. We found out that, in all cases, using nanocomposites as absorbance cannot get better results relative to pure nanoparticles. The frequency where absorption is maximum can determine the best choice between nanocomposites and pure nanoparticles. Also, we could find an optimal thickness for long wavelength absorbing in order to utilize them in protecting shields and covering.

Keywords: absorbing, carbon, carbon nickel, frequency, thicknesses

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3279 Evaluating the Effects of Rainfall and Agricultural Practices on Soil Erosion (Palapye Case Study)

Authors: Mpaphi Major

Abstract:

Soil erosion is becoming an important aspect of land degradation. Therefore it is of great consideration to note any factor that may escalate the rate of soil erosion in our arable land. There exist 3 main driving forces in soil erosion which are rainfall, wind and land use of which in this project only rainfall and land use will be looked at. With the increase in world population at an alarming rate, the demand for food production is expected to increase which will in turn lead to more land being converted from forests to agricultural use of which very few of it are now fertile. In our country Botswana, the rate of crop production is decreasing due to the wearing away of the fertile top soil and poor arable land management. As a result, some studies on the rate of soil loss and farm management practices should be conducted so that best soil and water conservation practices should be employed and hence reduce the risk of soil loss and increase the rate of crop production and yield. The Soil loss estimation model for Southern Africa (SLEMSA) will be used to estimate the rate of soil loss in some selected arable farms within the Palapye watershed and some field observations will be made to determine the management practices used and their impact on the arable land. Upon observations it have been found that many arable fields have been exposed to soil erosion, of which the affected parts are no longer suitable for any crop production unless the land areas are modified. Improper land practices such as ploughing along the slope and land cultivation practices were observed. As a result farmers need to be educated on best conservation practices that can be used to manage their arable land hence reduced risk of soil erosion and improved crop production.

Keywords: soil and water conservation, soil erosion, SLEMSA, land degradation

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3278 Investigation and Perfection of Centrifugal Compressor Stages by CFD Methods

Authors: Y. Galerkin, L. Marenina

Abstract:

Stator elements «Vane diffuser + crossover + return channel» of stages with different specific speed were investigated by CFD calculations. The regime parameter was introduced to present efficiency and loss coefficient performance of all elements together. Flow structure demonstrated advantages and disadvantages of design. Flow separation in crossovers was eliminated by its shape modification. Efficiency increased visibly. Calculated CFD performances are in acceptable correlation with predicted ones by engineering design method. The information obtained is useful for design method better calibration.

Keywords: vane diffuser, return channel, crossover, efficiency, loss coefficient, inlet flow angle

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3277 Aqueous Extract of Argemone Mexicana Roots for Effective Corrosion Inhibition of Mild Steel in HCl Environment

Authors: Gopal Ji, Priyanka Dwivedi, Shanthi Sundaram, Rajiv Prakash

Abstract:

Inhibition effect of aqueous Argemone Mexicana root extract (AMRE) on mild steel corrosion in 1 M HCl has been studied by weight loss, Tafel polarization curves, electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques. Results indicate that inhibition ability of AMRE increases with the increasing amount of the extract. A maximum corrosion inhibition of 94% is acknowledged at the extract concentration of 400 mg L-1. Polarization curves and impedance spectra reveal that both cathodic and anodic reactions are suppressed due to passive layer formation at metal-acid interface. It is also confirmed by SEM micro graphs and FTIR studies. Furthermore, the effects of acid concentration (1-5 M), immersion time (120 hours) and temperature (30-60˚C) on inhibition potential of AMRE have been investigated by weight loss method and electrochemical techniques. Adsorption mechanism is also proposed on the basis of weight loss results, which shows good agreement with Langmuir isotherm.

Keywords: mild steel, polarization, SEM, acid corrosion, EIS, green inhibition

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3276 Evaluation of the Inhibitive Effect of Novel Quinoline Schiff Base on Corrosion of Mild Steel in HCl Solution

Authors: Smita Jauhari, Bhupendra Mistry

Abstract:

Schiff base (E)-2-methyl-N-(tetrazolo[1,5-a]quinolin-4-ylmethylene)aniline (QMA) was synthesized, and its inhibitive effect for mild steel in 1M HCl solution was investigated by weight loss measurement and electrochemical tests.From the weight loss measurements and electrochemical tests, it was observed that the inhibition efficiency increases with the increase in the Schiff base concentration and reaches a maximum at the optimum concentration. This is further confirmed by the decrease in corrosion rate. It is found that the system follows Langmuir adsorption isotherm.

Keywords: Schiff base, acid corrosion, electrochemical impedance spectroscopy, polarization

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3275 The Effects of Some Organic Amendments on Sediment Yield, Splash Loss, and Runoff of Soils of Selected Parent Materials in Southeastern Nigeria

Authors: Leonard Chimaobi Agim, Charles Arinzechukwu Igwe, Emmanuel Uzoma Onweremadu, Gabreil Osuji

Abstract:

Soil erosion has been linked to stream sedimentation, ecosystem degradation, and loss of soil nutrients. A study was conducted to evaluate the effect of some organic amendment on sediment yield, splash loss, and runoff of soils of selected parent materials in southeastern Nigeria. A total of 20 locations, five from each of four parent materials namely: Asu River Group (ARG), Bende Ameki Group (BAG), Coastal Plain Sand (CPS) and Falsebedded Sandstone (FBS) were used for the study. Collected soil samples were analyzed with standard methods for the initial soil properties. Rainfall simulation at an intensity of 190 mm hr-1was conducted for 30 minutes on the soil samples at both the initial stage and after amendment to obtain erosion parameters. The influence of parent material on sediment yield, splash loss and runoff based on rainfall simulation was tested for using one way analyses of variance, while the influence of organic material and their combinations were a factorially fitted in a randomized complete block design. The organic amendments include; goat dropping (GD), poultry dropping (PD), municipal solid waste (MSW) and their combinations (COA) applied at four rates of 0, 10, 20 and 30 t ha-1 respectively. Data were analyzed using analyses of variance suitable for a factorial experiment. Significant means were separated using LSD at 5 % probability levels. Result showed significant (p ≤ 0.05) lower values of sediment yield, splash loss and runoff following amendment. For instance, organic amendment reduced sediment yield under wet and dry runs by 12.91 % and 26.16% in Ishiagu, 40.76% and 45.67%, in Bende, 16.17% and 50% in Obinze and 22.80% and 42.35% in Umulolo respectively. Goat dropping and combination of amendment gave the best results in reducing sediment yield.

Keywords: organic amendment, parent material, rainfall simulation, soil erosion

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3274 Analytic Hierarchy Process and Multi-Criteria Decision-Making Approach for Selecting the Most Effective Soil Erosion Zone in Gomati River Basin

Authors: Rajesh Chakraborty, Dibyendu Das, Rabindra Nath Barman, Uttam Kumar Mandal

Abstract:

In the present study, the objective is to find out the most effective zone causing soil erosion in the Gumati river basin located in the state of Tripura, a north eastern state of India using analytical hierarchy process (AHP) and multi-objective optimization on the basis of ratio analysis (MOORA).The watershed is segmented into 20 zones based on Area. The watershed is considered by pointing the maximum elevation from sea lever from Google earth. The soil erosion is determined using the universal soil loss equation. The different independent variables of soil loss equation bear different weightage for different soil zones. And therefore, to find the weightage factor for all the variables of soil loss equation like rainfall runoff erosivity index, soil erodibility factor etc, analytical hierarchy process (AHP) is used. And thereafter, multi-objective optimization on the basis of ratio analysis (MOORA) approach is used to select the most effective zone causing soil erosion. The MCDM technique concludes that the maximum soil erosion is occurring in the zone 14.

Keywords: soil erosion, analytic hierarchy process (AHP), multi criteria decision making (MCDM), universal soil loss equation (USLE), multi-objective optimization on the basis of ratio analysis (MOORA)

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3273 Accessing Livestock Depredation by the Himalayan Wolf in Neshyang Valley, Manag, Nepal

Authors: Tenzing Lama, Ganga Ram Regmi, Thakur Silwal, Rinzin Punjok Lama

Abstract:

Livestock depredation by a wolf and associated financial loss suffered by herders is perhaps the most important issue leading to human-wolf conflict. As a result, recolonized wolves remained one of the most persecuted large carnivores in Nepal Himalaya suffering high mortality due to retaliatory killings by herdsmen. Reducing such depredation are crucial in gaining herder’s support in conservation program to ensure the long-term survival of such carnivores. In February 2018, a study was conducted through questionnaire survey with 33 herders from different settlements in Neshyang valley of Manang district to assess the status of human-wolf conflict in terms of livestock loss and herder’s attitude. A total of 36 livestock were lost to the wolf with an average loss of 1.09 ± 0.48 (SE) livestock heads per herder between March 2017 to February 2018 which represents 1.5% of the total holdings. The estimated financial value of livestock loss was equivalent to US$ 25,428 with an average of US$ 770 per herder. Majority of the herders (80%) expressed a negative attitude towards the wolf, but only a few herders (6.06%) suggested removal of the wolf from the valley. The incidences of livestock loss differed significantly with highest in day time and seasonally highest in winter, when herders freely leaves their livestock (except goat/sheep) in the pastures. Wolf showed positive selectivity to the horse (EI=0.59), yak (EI=0.24) and cattle (EI=0.14) but strong avoidance to goat/sheep (EI=-1). This study suggests that livestock depredation by wolf could be minimized through improved livestock husbandry practices and implication of mitigation measures (e.g. coral improvement) and immediate relief to the victims. Conservation education and awareness programs to enhance herders knowledge about the ecological importance of wolf, provision of relief scheme and law enforcement.

Keywords: canis lupus canco, conservation education, human wildlife conflict, compensation schemes

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3272 Drastic Improvement in Vision Following Surgical Excision of Juvenile Nasopharyngeal Angiofibroma with Compressive Optic Neuropathy

Authors: Sweta Das

Abstract:

This case report is a 15-year-old male who presented with painless unilateral vision loss from left optic nerve compression due to juvenile nasopharyngeal angiofibroma. JNA is a rare, benign neoplasm that causes intracranial and intraorbital bone destruction and extends aggressively into surrounding soft tissues. It accounts for <1% of all head and neck tumors, is predominantly found in pediatric males and tends to affect indigenous population disproportionately. The most common presenting symptom for JNA is epistaxis and nasal obstruction. However, it can invade orbit, chiasm and pituitary gland, causing loss of vision and field. Visual acuity and function near normalized following surgical excision. Optometry plays an important role in the diagnosis and co-management of JNA with optic nerve compression by closely monitoring afferent optic nerve function and structure, and extraocular motility. Visual function and acuity in patients with short-term compressive neuropathy may drastically improve following surgical resection as this case demonstrates.

Keywords: orbital mass, painless monocular vision loss, compressive optic neuropathy, pediatric tumor

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3271 Donoho-Stark’s and Hardy’s Uncertainty Principles for the Short-Time Quaternion Offset Linear Canonical Transform

Authors: Mohammad Younus Bhat

Abstract:

The quaternion offset linear canonical transform (QOLCT), which isa time-shifted and frequency-modulated version of the quaternion linear canonical transform (QLCT), provides a more general framework of most existing signal processing tools. For the generalized QOLCT, the classical Heisenberg’s and Lieb’s uncertainty principles have been studied recently. In this paper, we first define the short-time quaternion offset linear canonical transform (ST-QOLCT) and drive its relationship with the quaternion Fourier transform (QFT). The crux of the paper lies in the generalization of several well-known uncertainty principles for the ST-QOLCT, including Donoho-Stark’s uncertainty principle, Hardy’s uncertainty principle, Beurling’s uncertainty principle, and the logarithmic uncertainty principle.

Keywords: Quaternion Fourier transform, Quaternion offset linear canonical transform, short-time quaternion offset linear canonical transform, uncertainty principle

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3270 Managing Incomplete PSA Observations in Prostate Cancer Data: Key Strategies and Best Practices for Handling Loss to Follow-Up and Missing Data

Authors: Madiha Liaqat, Rehan Ahmed Khan, Shahid Kamal

Abstract:

Multiple imputation with delta adjustment is a versatile and transparent technique for addressing univariate missing data in the presence of various missing mechanisms. This approach allows for the exploration of sensitivity to the missing-at-random (MAR) assumption. In this review, we outline the delta-adjustment procedure and illustrate its application for assessing the sensitivity to deviations from the MAR assumption. By examining diverse missingness scenarios and conducting sensitivity analyses, we gain valuable insights into the implications of missing data on our analyses, enhancing the reliability of our study's conclusions. In our study, we focused on assessing logPSA, a continuous biomarker in incomplete prostate cancer data, to examine the robustness of conclusions against plausible departures from the MAR assumption. We introduced several approaches for conducting sensitivity analyses, illustrating their application within the pattern mixture model (PMM) under the delta adjustment framework. This proposed approach effectively handles missing data, particularly loss to follow-up.

Keywords: loss to follow-up, incomplete response, multiple imputation, sensitivity analysis, prostate cancer

Procedia PDF Downloads 89