Search results for: a modified estimation equation
Commenced in January 2007
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Edition: International
Paper Count: 6059

Search results for: a modified estimation equation

1889 Numerical Simulation of Transient 3D Temperature and Kerf Formation in Laser Fusion Cutting

Authors: Karim Kheloufi, El Hachemi Amara

Abstract:

In the present study, a three-dimensional transient numerical model was developed to study the temperature field and cutting kerf shape during laser fusion cutting. The finite volume model has been constructed, based on the Navier–Stokes equations and energy conservation equation for the description of momentum and heat transport phenomena, and the Volume of Fluid (VOF) method for free surface tracking. The Fresnel absorption model is used to handle the absorption of the incident wave by the surface of the liquid metal and the enthalpy-porosity technique is employed to account for the latent heat during melting and solidification of the material. To model the physical phenomena occurring at the liquid film/gas interface, including momentum/heat transfer, a new approach is proposed which consists of treating friction force, pressure force applied by the gas jet and the heat absorbed by the cutting front surface as source terms incorporated into the governing equations. All these physics are coupled and solved simultaneously in Fluent CFD®. The main objective of using a transient phase change model in the current case is to simulate the dynamics and geometry of a growing laser-cutting generated kerf until it becomes fully developed. The model is used to investigate the effect of some process parameters on temperature fields and the formed kerf geometry.

Keywords: laser cutting, numerical simulation, heat transfer, fluid flow

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1888 Impact of Modifying the Surface Materials on the Radiative Heat Transfer Phenomenon

Authors: Arkadiusz Urzędowski, Dorota Wójcicka-Migasiuk, Andrzej Sachajdak, Magdalena Paśnikowska-Łukaszuk

Abstract:

Due to the impact of climate changes and inevitability to reduce greenhouse gases, the need to use low-carbon and sustainable construction has increased. In this work, it is investigated how texture of the surface building materials and radiative heat transfer phenomenon in flat multilayer can be correlated. Attempts to test the surface emissivity are taken however, the trustworthiness of measurement results remains a concern since sensor size and thickness are common problems. This paper presents an experimental method to studies surface emissivity with use self constructed thermal sensors and thermal imaging technique. The surface of building materials was modified by mechanical and chemical treatment affecting the reduction of the emissivity. For testing the shaping surface of materials and mapping its three-dimensional structure, scanning profilometry were used in a laboratory. By comparing the results of laboratory tests and performed analysis of 3D computer fluid dynamics software, it can be shown that a change in the surface coverage of materials affects the heat transport by radiation between layers. Motivated by recent advancements in variational inference, this publication evaluates the potential use a dedicated data processing approach, and properly constructed temperature sensors, the influence of the surface emissivity on the phenomenon of radiation and heat transport in the entire partition can be determined.

Keywords: heat transfer, surface roughness, surface emissivity, radiation

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1887 Review of Vertical Axis Wind Turbine

Authors: Amare Worku, Harikrishnan Muralidharan

Abstract:

The research for more environmentally friendly sources of energy is a result of growing environmental awareness. In this aspect, wind energy is a very good option and there are two different wind turbines, horizontal axis wind turbine (HAWT) and vertical axis turbine (VAWT). For locations outside of integrated grid networks, vertical axis wind turbines (VAWT) present a feasible solution. However, those turbines have several drawbacks related to various setups, VAWT has a very low efficiency when compared with HAWT, but they work under different conditions and installation areas. This paper reviewed numerous measurements taken to improve the efficiency of VAWT configurations, either directly or indirectly related to the performance efficiency of the turbine. Additionally, the comparison and advantages of HAWT and VAWT turbines and also the findings of the design methodologies used for the VAWT design have been reviewed together with efficiency enhancement revision. Most of the newly modified designs are based on the turbine blade structure modification but need other studies on behalf other than electromechanical modification. Some of the techniques, like continuous variation of pitch angle control and swept area control, are not the most effective since VAWT is Omni-directional, and so wind direction is not a problem like HAWT. Hybrid system technology has become one of the most important and efficient methods to enhance the efficiency of VAWT. Besides hybridization, the contra-rotating method is also good if the installation area is big enough in an urban area.

Keywords: wind turbine, horizontal axis wind turbine, vertical axis wind turbine, hybridization

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1886 A Compact Ultra-Wide Band Antenna with C-Shaped Slot for WLAN Notching

Authors: Maryam Rasool, Farhan Munir, Fahad Nawaz, Saad Ahmad

Abstract:

A patch antenna operating in the Ultra-Wide Band of frequency (3.1 GHz – 10.6 GHz) is designed with enhanced security from interference from other applications by incorporating the notching technique. Patch antennas in the Ultra-Wide Band are becoming widely famous due to their low power, light weight and high data rate capability. Micro strip patch antenna’s patch can be altered to increase its bandwidth and introduce UWB character in it. The designed antenna is a patch antenna consisting of a conductive sheet of metal mounted over a large sheet of metal called the ground plane with a substrate separating the two. Notched bands are public safety WLAN, WLAN and FSS. Different techniques used to implement the UWB antenna were individually implemented and there results were examined. V shaped patch was then chosen and modified to an arrow shaped patch to give the optimized results operating on the entire UWB region with considerable return loss. The frequency notch prevents the operation of the antenna at a particular range of frequency, hence minimizing interference from other systems. There are countless techniques for introducing the notch but we have used inverted C-shaped slots in the UWB patch to get the notch characteristics as output and also wavelength resonators to introduce notch in UWB band. The designed antenna is simulated in High Frequency Structural Simulator (HFSS) 13.0 by Ansoft.

Keywords: HFSS, Notch, UWB, WLAN

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1885 Intimate Partner Violence and Risk of Obesity among Women

Authors: Fatemeh Abdollahi, Munn-Sann Lye, Jamshid Yazdani Charati, Mehran Zarghami

Abstract:

Both obesity and intimate partner violence (IPV) are growing health threats. This study aimed to assess the prevalence and risk factors of both IPV and obesity and their association. In this cross-sectional study, 530 women aged 16-65 years attending Mazandaran primary health centers were recruited through the stratified random sampling method (2019-2020). Data were collected using the modified World Health Organization Domestic Violence questionnaire, Perceived Stress Scale, and socio-demographic, obstetric, and anthropometric questionnaires. The data were analyzed using descriptive statistics, the chi-square test, and multiple logistic regression. The prevalence of overweight, obesity and psychological, physical, and sexual IPV were 47.6%, 26.7%, 70.4%, 17.9%, and 6.4%, respectively. Increasing women’s educational level and exposure to violence during their lifespan increased the odds of any type of IPV while living in a nuclear family reduced it. In groups of women who were subjected to any type of IPV and only psychological IPV, experiencing violence during the lifespan was significant in predicting obesity. The alarming prevalence of IPV and obesity-overweight in this study points to the need for collaborative socio-political and health intervention. The link between experiencing violence during lifespan and obesity in some subgroups of women highlights the detrimental consequences of chronic violence and the urgent need for effective preventive programs.

Keywords: intimate partner violence, body mass index, obesity, risk factor, women

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1884 Localized Analysis of Cellulosic Fibrous Insulation Materials

Authors: Chady El Hachem, Pan Ye, Kamilia Abahri, Rachid Bennacer

Abstract:

Considered as a building construction material, and regarding its environmental benefits, wood fiber insulation is the material of interest in this work. The definition of adequate elementary representative volume that guarantees reliable understanding of the hygrothermal macroscopic phenomena is very critical. At the microscopic scale, when subjected to hygric solicitations, fibers undergo local dimensionless variations. It is therefore necessary to master this behavior, which affects the global response of the material. This study consists of an experimental procedure using the non-destructive method, X-ray tomography, followed by morphological post-processing analysis using ImageJ software. A refine investigation took place in order to identify the representative elementary volume and the sufficient resolution for accurate structural analysis. The second part of this work was to evaluate the microscopic hygric behavior of the studied material. Many parameters were taken into consideration, like the evolution of the fiber diameters, distribution along the sorption cycle and the porosity, and the water content evolution. In addition, heat transfer simulations based on the energy equation resolution were achieved on the real structure. Further, the problematic of representative elementary volume was elaborated for such heterogeneous material. Moreover, the material’s porosity and its fibers’ thicknesses show very big correlation with the water content. These results provide the literature with very good understanding of wood fiber insulation’s behavior.

Keywords: hygric behavior, morphological characterization, wood fiber insulation material, x-ray tomography

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1883 Silver Nanoparticles in Drinking Water Purification

Authors: S. Pooja Pragati, B. Sudarsan, S. Rajkumar

Abstract:

Silver nanoparticles (AgNP) are known for their excellent antimicrobial agents, and thus can be used as alternative disinfectant agents. However, released silver nanoparticles is a threat to naturally occurring microorganisms. This paper exhibits information on the environmental fate, toxicological effects, and application of AgNP and the current estimate on the physicochemical and antimicrobial properties of AgNP in different aqueous solutions, as well as their application as alternative disinfectants in water-treatment systems. It also gives a better approximation and experimental data of AgNP’s antimicrobial properties at different water chemistry conditions. A saturation-type fitting curve was established, showing the survival of bacteria under different water chemistry conditions as a function of the size of the nanoparticles. The results obtained show that silver nanoparticles in surface water, ground water, and brackish water are stable. The paper demonstrates the comparative study of AgNP-impregnated point-of-use ceramic water filters and ceramic filters impregnated with silver nitrate. It is observed that AgNP-impregnated ceramic water filters are more appropriate for this application due to the lesser amount of silver desorbed. Experimental data of the comparison of a polymer-based quaternary amine functionalized silsesquioxanes compound and AgNP are also tabulated and conclusions are analysed with the goal of optimizing. The simplicity of synthesis and application of Silver nanoparticles enables us to consider its effective modified version for the purification of water.

Keywords: disinfectant agent, purification of water, nano particles, water treatment

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1882 Modeling and Performance Analysis of an Air-Cooled Absorption Chiller

Authors: A. Roukbi, B. Draoui

Abstract:

Due to the high cost and the environmental problems caused by the conventional air-conditioning systems, various researches are being increasingly focused on thermal comfort in the building sector integrating renewable energy sources, particularly solar energy. For that purpose, this study aims to present a modeling and performance analysis of a direct air-cooled Water/LiBr absorption chiller. The chiller is considered to be coupled to a small residential building at an arid zone situated in south Algeria. The system is modeled with TRNSYS simulation program. The main objective is to study the feasibility of the chosen system in arid zones and to apply a simplified method to predict the performance of the system by mean of the characteristic equation approach tacking in account the influence of the climatic conditions of the considered site, the collector area and storage volume of the hot water tank on the performance of the installation. First, the results of the system modeling are compared with an experimental data from the open literature and the developed model is then validated. In another hand, a parametric study is performed to analyze the performance of the direct air-cooled absorption chiller at the operating conditions of interest for the present study. Thus, the obtained results has shown that the studied system can present a good alternative for cooling systems in arid zones since the cooling load is roughly in phase with solar availability.

Keywords: absorption chiller, air-cooled, arid zone, thermal comfort

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1881 Using Scanning Electron Microscope and Computed Tomography for Concrete Diagnostics of Airfield Pavements

Authors: M. Linek

Abstract:

This article presents the comparison of selected evaluation methods regarding microstructure modification of hardened cement concrete intended for airfield pavements. Basic test results were presented for two pavement quality concrete lots. Analysis included standard concrete used for airfield pavements and modern material solutions based on concrete composite modification. In case of basic grain size distribution of concrete cement CEM I 42,5HSR NA, fine aggregate and coarse aggregate fractions in the form of granite chippings, water and admixtures were considered. In case of grain size distribution of modified concrete, the use of modern modifier as substitute of fine aggregate was suggested. Modification influence on internal concrete structure parameters using scanning electron microscope was defined. Obtained images were compared to the results obtained using computed tomography. Opportunity to use this type of equipment for internal concrete structure diagnostics and an attempt of its parameters evaluation was presented. Obtained test results enabled to reach a conclusion that both methods can be applied for pavement quality concrete diagnostics, with particular purpose of airfield pavements.

Keywords: scanning electron microscope, computed tomography, cement concrete, airfield pavements

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1880 Techno-Economic Analysis of the Production of Aniline

Authors: Dharshini M., Hema N. S.

Abstract:

The project for the production of aniline is done by providing 295.46 tons per day of nitrobenzene as feed. The material and energy balance calculations for the different equipment like distillation column, heat exchangers, reactor and mixer are carried out with simulation via DWSIM. The conversion of nitrobenzene to aniline by hydrogenation process is considered to be 96% and the total production of the plant was found to be 215 TPD. The cost estimation of the process is carried out to estimate the feasibility of the plant. The net profit and percentage return of investment is estimated to be ₹27 crores and 24.6%. The payback period was estimated to be 4.05 years and the unit production cost is ₹113/kg. A techno-economic analysis was performed for the production of aniline; the result includes economic analysis and sensitivity analysis of critical factors. From economic analysis, larger the plant scale increases the total capital investment and annual operating cost, even though the unit production cost decreases. Uncertainty analysis was performed to predict the influence of economic factors on profitability and the scenario analysis is one way to quantify uncertainty. In scenario analysis the best-case scenario and the worst-case scenario are compared with the base case scenario. The best-case scenario was found at a feed rate of 120 kmol/hr with a unit production cost of ₹112.05/kg and the worst-case scenario was found at a feed rate of 60 kmol/hr with a unit production cost of ₹115.9/kg. The base case is closely related to the best case by 99.2% in terms of unit production cost. since the unit production cost is less and the profitability is more with less payback time, it is feasible to construct a plant at this capacity.

Keywords: aniline, nitrobenzene, economic analysis, unit production cost

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1879 Green Synthesis and Characterization of Zinc Oxide Nanoparticles Using Neem (Azadiractha Indica) Leaf Extract and Investigate Its Antibacterial Activities

Authors: Elmineh Tsegahun Gedif

Abstract:

Zinc oxide nanoparticles (ZnO NPs) have attracted huge attention due to catalytic, optical, photonic, and antibacterial activity. Zinc oxide nanoparticles were successfully synthesized via a fast, non-toxic, cost-effective, and eco-friendly method by biologically reducing Zn(NO3)2.6H2O solution with Neem (Azadirachta indica) leaf extract under optimum conditions (pH = 9). The presence of active flavonoids, phenolic groups, alkaloids, terpenoids, and tannins, which were in the biomass of the Neem leaf extract before and after reduction, was identified using qualitative screening methods (observing the color changes) and FT-IR Spectroscopy. The formation of ZnO NPs was visually indicated by the color changes from colorless to light yellow color. Biosynthesized nanoparticles were also characterized by UV-visible, FT-IR, and XRD spectroscopies. The reduction process was simple and convenient to handle and was monitored by UV-visible spectroscopy that showed surface plasmon resonance (SPR) of the ZnO NPs at 321 nm. This result clearly revealed the formation of ZnO NPs. X-ray diffraction was used to investigate the crystal structure. The average particle size of ZnO powder and around 20 nm using the line width of the plane, and the refraction peak using Scherrer’s equation. The synthesized zinc oxide nanoparticles were evaluated for antimicrobial activities against Gram-positive and Gram-negative bacteria. Zinc nanoparticles exhibited the maximum zone of inhibition against Escherichia coli (15 mm), while the least activity was seen against Staphylococcus aureus.

Keywords: antimicrobial activity, azadirachta indica, green synthesis, ZnO NPs

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1878 Physicochemical Properties of Soy Protein Isolate (SPI): Starch Conjugates Treated by Sonication

Authors: Gulcin Yildiz, Hao Feng

Abstract:

In recent years there is growing interested in using soy protein because of several advantages compared to other protein sources, such as high nutritional value, steady supply, and low cost. Soy protein isolate (SPI) is the most refined soy protein product. It contains 90% protein in a moisture-free form and has some desirable functionalities. Creating a protein-polysaccharide conjugate to be the emulsifying agent rather than the protein alone can markedly enhance its stability. This study was undertaken to examine the effects of ultrasound treatments on the physicochemical properties of SPI-starch conjugates. The soy protein isolate (SPI, Pro-Fam® 955) samples were obtained from the Archer Daniels Midland Company. Protein concentrations were analyzed by the Bardford method using BSA as the standard. The volume-weighted mean diameters D [4,3] of protein–polysaccharide conjugates were measured by dynamic light scattering (DLS). Surface hydrophobicity of the conjugates was measured by using 1-anilino-8-naphthalenesulfonate (ANS) (Sigma-Aldrich, St. Louis, MO, USA). Increasing the pH from 2 to 12 resulted in increased protein solubility. The highest solubility was 69.2% for the sample treated with ultrasonication at pH 12, while the lowest (9.13%) was observed in the Control. For the other pH conditions, the protein solubility values ranged from 40.53 to 49.65%. The ultrasound treatment significantly decreased the particle sizes of the SPI-modified starch conjugates. While the D [4,3] for the Control was 731.6 nm, it was 293.7 nm for the samples treated by sonication at pH 12. The surface hydrophobicity (H0) of SPI-starch at all pH conditions were significantly higher than those in the Control. Ultrasonication was proven to be effective in improving the solubility and emulsifying properties of soy protein isolate-starch conjugates.

Keywords: particle size, solubility, soy protein isolate, ultrasonication

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1877 Estimation of PM10 Concentration Using Ground Measurements and Landsat 8 OLI Satellite Image

Authors: Salah Abdul Hameed Saleh, Ghada Hasan

Abstract:

The aim of this work is to produce an empirical model for the determination of particulate matter (PM10) concentration in the atmosphere using visible bands of Landsat 8 OLI satellite image over Kirkuk city- IRAQ. The suggested algorithm is established on the aerosol optical reflectance model. The reflectance model is a function of the optical properties of the atmosphere, which can be related to its concentrations. The concentration of PM10 measurements was collected using Particle Mass Profiler and Counter in a Single Handheld Unit (Aerocet 531) meter simultaneously by the Landsat 8 OLI satellite image date. The PM10 measurement locations were defined by a handheld global positioning system (GPS). The obtained reflectance values for visible bands (Coastal aerosol, Blue, Green and blue bands) of landsat 8 OLI image were correlated with in-suite measured PM10. The feasibility of the proposed algorithms was investigated based on the correlation coefficient (R) and root-mean-square error (RMSE) compared with the PM10 ground measurement data. A choice of our proposed multispectral model was founded on the highest value correlation coefficient (R) and lowest value of the root mean square error (RMSE) with PM10 ground data. The outcomes of this research showed that visible bands of Landsat 8 OLI were capable of calculating PM10 concentration with an acceptable level of accuracy.

Keywords: air pollution, PM10 concentration, Lansat8 OLI image, reflectance, multispectral algorithms, Kirkuk area

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1876 Survey on Prevalence of Endo and Ecto-Parasites of Rattus rattus in Mazandaran Province, North of Iran

Authors: Fatemeh Rezaei, Afsaneh Amouei, Iman Bakouei, Mahdi Sharif, Shahabeddin Sarvi, Mohammad Taghi Rahimi, Ahmad Daryani

Abstract:

Background: Rodents act as reservoir host and important potential source for many zoonotic pathogens which pose a public health risk to humans. Therefore, it is necessary to investigate the prevalence of gastrointestinal and ectoparasites among rodents. Materials and Methods: 118 Rattus rattus were captured using snap live traps. Each rat was combed with a fine tooth comb to dislodge ectoparasite and studied. Various samples were collected from feces, examined wet smear, formalin-ether method and stained with modified acid-fast staining and trichrome. Result: The overall prevalence of gastrointestinal parasites of examined rats was 75.4%. Cryptosporidium 30.5%, was the most prevalent protozoan which was followed by Giardia 20.3% and Entamoeba muris 13.5%, Trichomonas muris 10.1% and Spironucleus muris 3.3%. The prevalence of helminth egg was as following Syphacia obvelata 24.5%, Hymenolepis diminuta 10.1% and Trichuris muris 9.3%. 86.4% rodents were found to be infested with ectoparasites including mite 35.6%, flea 28.4%, and lice 42.7%. A significant statistical difference was observed between prevalence and gender of infected individuals. Conclusions: The prevalence of gastrointestinal and ectoparasites of collected rats in studied area is remarkably high. In addition, Rattus rattus can be considered as potential risk for human health.

Keywords: prevalence, rodent, intestinal parasites, ecto-parasites, zoonose

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1875 Transmission of Values among Polish Young Adults and Their Parents: Pseudo Dyad Analysis and Gender Differences

Authors: Karolina Pietras, Joanna Fryt, Aleksandra Gronostaj, Tomasz Smolen

Abstract:

Young women and men differ from their parents in preferred values. Those differences enable their adaptability to a new socio-cultural context and help with fulfilling developmental tasks specific to young adulthood. At the same time core values, with special importance to family members, are transmitted within families. Intergenerational similarities in values may thus be both an effect of value transmission within a family and a consequence of sharing the same socio-cultural context. These processes are difficult to separate. In our study we assessed similarities and differences in values within four intergenerational family dyads (mothers-daughters, fathers-daughters, mothers-sons, fathers-sons). Sixty Polish young adults (30 women and 30 men aged 19-25) along with their parents (a total of 180 participants) completed the Schwartz’ Portrait Value Questionnaire (PVQ-21). To determine which values may be transmitted within families, we used a correlation analysis and pseudo dyad analysis that allows for the estimation of a baseline likeness between all tested subjects and consequently makes it possible to determine if similarities between actual family members are greater than chance. We also assessed whether different strategies of measuring similarity between family members render different results, and checked whether resemblances in family dyads are influenced by child’s and parent’s gender. Reported similarities were interpreted in light of the evolutionary and the value salience perspective.

Keywords: intergenerational differences in values, gender differences, pseudo dyad analysis, transmission of values

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1874 Feedback Matrix Approach for Relativistic Runaway Electron Avalanches Dynamics in Complex Electric Field Structures

Authors: Egor Stadnichuk

Abstract:

Relativistic runaway electron avalanches (RREA) are a widely accepted source of thunderstorm gamma-radiation. In regions with huge electric field strength, RREA can multiply via relativistic feedback. The relativistic feedback is caused both by positron production and by runaway electron bremsstrahlung gamma-rays reversal. In complex multilayer thunderstorm electric field structures, an additional reactor feedback mechanism appears due to gamma-ray exchange between separate strong electric field regions with different electric field directions. The study of this reactor mechanism in conjunction with the relativistic feedback with Monte Carlo simulations or by direct solution of the kinetic Boltzmann equation requires a significant amount of computational time. In this work, a theoretical approach to study feedback mechanisms in RREA physics is developed. It is based on the matrix of feedback operators construction. With the feedback matrix, the problem of the dynamics of avalanches in complex electric structures is reduced to the problem of finding eigenvectors and eigenvalues. A method of matrix elements calculation is proposed. The proposed concept was used to study the dynamics of RREAs in multilayer thunderclouds.

Keywords: terrestrial Gamma-ray flashes, thunderstorm ground enhancement, relativistic runaway electron avalanches, gamma-rays, high-energy atmospheric physics, TGF, TGE, thunderstorm, relativistic feedback, reactor feedback, reactor model

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1873 Quality Service Standard of Food and Beverage Service Staff in Hotel

Authors: Thanasit Suksutdhi

Abstract:

This survey research aims to study the standard of service quality of food and beverage service staffs in hotel business by studying the service standard of three sample hotels, Siam Kempinski Hotel Bangkok, Four Seasons Resort Chiang Mai, and Banyan Tree Phuket. In order to find the international service standard of food and beverage service, triangular research, i.e. quantitative, qualitative, and survey were employed. In this research, questionnaires and in-depth interview were used for getting the information on the sequences and method of services. There were three parts of modified questionnaires to measure service quality and guest’s satisfaction including service facilities, attentiveness, responsibility, reliability, and circumspection. This study used sample random sampling to derive subjects with the return rate of the questionnaires was 70% or 280. Data were analyzed by SPSS to find arithmetic mean, SD, percentage, and comparison by t-test and One-way ANOVA. The results revealed that the service quality of the three hotels were in the international level which could create high satisfaction to the international customers. Recommendations for research implementations were to maintain the area of good service quality, and to improve some dimensions of service quality such as reliability. Training in service standard, product knowledge, and new technology for employees should be provided. Furthermore, in order to develop the service quality of the industry, training collaboration between hotel organization and educational institutions in food and beverage service should be considered.

Keywords: service standard, food and beverage department, sequence of service, service method

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1872 Estimation of Geotechnical Parameters by Comparing Monitoring Data with Numerical Results: Case Study of Arash–Esfandiar-Niayesh Under-Passing Tunnel, Africa Tunnel, Tehran, Iran

Authors: Aliakbar Golshani, Seyyed Mehdi Poorhashemi, Mahsa Gharizadeh

Abstract:

The under passing tunnels are strongly influenced by the soils around. There are some complexities in the specification of real soil behavior, owing to the fact that lots of uncertainties exist in soil properties, and additionally, inappropriate soil constitutive models. Such mentioned factors may cause incompatible settlements in numerical analysis with the obtained values in actual construction. This paper aims to report a case study on a specific tunnel constructed by NATM. The tunnel has a depth of 11.4 m, height of 12.2 m, and width of 14.4 m with 2.5 lanes. The numerical modeling was based on a 2D finite element program. The soil material behavior was modeled by hardening soil model. According to the field observations, the numerical estimated settlement at the ground surface was approximately four times more than the measured one, after the entire installation of the initial lining, indicating that some unknown factors affect the values. Consequently, the geotechnical parameters are accurately revised by a numerical back-analysis using laboratory and field test data and based on the obtained monitoring data. The obtained result confirms that typically, the soil parameters are conservatively low-estimated. And additionally, the constitutive models cannot be applied properly for all soil conditions.

Keywords: NATM tunnel, initial lining, laboratory test data, numerical back-analysis

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1871 Factor Affecting Decision Making for Tourism in Thailand by ASEAN Tourists

Authors: Sakul Jariyachansit

Abstract:

The purposes of this research were to investigate and to compare the factors affecting the decision for Tourism in Thailand by ASEAN Tourists and among ASEAN community tourists. Samples in this research were 400 ASEAN Community Tourists who travel in Thailand at Suvarnabhumi Airport during November 2016 - February 2016. The researchers determined the sample size by using the formula Taro Yamane at 95% confidence level tolerances 0.05. The English questionnaire, research instrument, was distributed by convenience sampling, for gathering data. Descriptive statistics was applied to analyze percentages, mean and standard deviation and used for hypothesis testing. The statistical analysis by multiple regression analysis (Multiple Regression) was employed to prove the relationship hypotheses at the significant level of 0.01. The results showed that majority of the respondents indicated the factors affecting the decision for Tourism in Thailand by ASEAN Tourists, in general there were a moderate effects and the mean of each side is moderate. Transportation was the most influential factor for tourism in Thailand. Therefore, the mode of transport, information, infrastructure and personnel are very important to factor affecting decision making for tourism in Thailand by ASEAN tourists. From the hypothesis testing, it can be predicted that the decision for choosing Tourism in Thailand is at R2 = 0.449. The predictive equation is decision for choosing Tourism in Thailand = 1.195 (constant value) + 0.425 (tourist attraction) +0.217 (information received) and transportation factors, tourist attraction, information, human resource and infrastructure at the significant level of 0.01.

Keywords: factor, decision making, ASEAN tourists, tourism in Thailand

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1870 Determinants of Economic Growth in Pakistan: A Structural Vector Auto Regression Approach

Authors: Muhammad Ajmair

Abstract:

This empirical study followed structural vector auto regression (SVAR) approach proposed by the so-called AB-model of Amisano and Giannini (1997) to check the impact of relevant macroeconomic determinants on economic growth in Pakistan. Before that auto regressive distributive lag (ARDL) bound testing technique and time varying parametric approach along with general to specific approach was employed to find out relevant significant determinants of economic growth. To our best knowledge, no author made such a study that employed auto regressive distributive lag (ARDL) bound testing and time varying parametric approach with general to specific approach in empirical literature, but current study will bridge this gap. Annual data was taken from World Development Indicators (2014) during period 1976-2014. The widely-used Schwarz information criterion and Akaike information criterion were considered for the lag length in each estimated equation. Main findings of the study are that remittances received, gross national expenditures and inflation are found to be the best relevant positive and significant determinants of economic growth. Based on these empirical findings, we conclude that government should focus on overall economic growth augmenting factors while formulating any policy relevant to the concerned sector.

Keywords: economic growth, gross national expenditures, inflation, remittances

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1869 Fabrication of Gold Nanoparticles Self-Assembled Functionalized Improved Graphene on Carbon Paste Electrode for Electrochemical Determination of Levodopa in the Presence of Ascorbic Acid

Authors: Mohammad Ali Karimi, Hossein Tavallali, Abdolhamid Hatefi-Mehrjardi

Abstract:

In this study, an electrochemical sensor based on gold nanoparticles (AuNPs) functionalized improved graphene (AuNPs-IGE) was fabricated for selective determination of L-dopa in the presence of ascorbic acid by a novel self-assembly method. The AuNP IGE modified carbon paste electrode (AuNPs-IGE/CPE) utilized for investigation of the electrochemical behavior of L-dopa in phosphate buffer solution. Compared to bare CPE, AuNPs-IGE/CPE shows novel properties towards the electrochemical redox of levodopa (L-dopa) in phosphate buffer solution at pH 4.0. The oxidation potential of L-dopa shows a significant decrease at the AuNPs-IGE/CPE. The oxidation current of L-dopa is higher than that of the unmodified CPE. AuNPs-IG/CPE shows excellent electrocatalytic activity for the oxidation of ascorbic acid (AA). Using differential pulse voltammetry (DPV) method, the oxidation current is well linear with L-dopa concentration in the range of 0.4–50 µmol L-1, with a detection limit of about 1.41 nmol L-1 (S/N = 3). Therefore, it was applied to measure L-dopa from real samples that recoveries are 94.6-106.2%. The proposed electrode can also effectively avoid the interference of ascorbic acid, making the proposed sensor suitable for the accurate determination of L-dopa in both pharmaceutical preparations and human body fluids.

Keywords: gold nanoparticles, improved graphene, L-dopa, self-assembly

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1868 Theoretical Analysis of the Optical and Solid State Properties of Thin Film

Authors: E. I. Ugwu

Abstract:

Theoretical analysis of the optical and Solid State properties of ZnS thin film using beam propagation technique in which a scalar wave is propagated through the material thin film deposited on a substrate with the assumption that the dielectric medium is section into a homogenous reference dielectric constant term, and a perturbed dielectric term, representing the deposited thin film medium is presented in this work. These two terms, constitute arbitrary complex dielectric function that describes dielectric perturbation imposed by the medium of for the system. This is substituted into a defined scalar wave equation in which the appropriate Green’s Function was defined on it and solved using series technique. The green’s value obtained from Green’s Function was used in Dyson’s and Lippmann Schwinger equations in conjunction with Born approximation method in computing the propagated field for different input regions of field wavelength during which the influence of the dielectric constants and mesh size of the thin film on the propagating field were depicted. The results obtained from the computed field were used in turn to generate the data that were used to compute the band gaps, solid state and optical properties of the thin film such as reflectance, Transmittance and reflectance with which the band gap obtained was found to be in close approximate to that of experimental value.

Keywords: scalar wave, optical and solid state properties, thin film, dielectric medium, perturbation, Lippmann Schwinger equations, Green’s Function, propagation

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1867 Life Table and Functional Response of Scolothrips takahashii (Thysanoptera: Thripidae) on Tetranychus urticae (Acari:Tetranychidae)

Authors: Kuang-Chi Pan, Shu-Jen Tuan

Abstract:

Scolothrips takahashii Priesner (Thysanoptera: Thripidae) is a common predatory thrips which feeds on spider mites; it is considered an important natural enemy and a potential biological control agent against spider mites. In order to evaluate the efficacy of S. takahashii against tetranychid mites, life table and functional response study were conducted at 25±1°C, with Tetranychus urticae Priesner as prey. The intrinsic rate of increase (r), finite rate of increase (λ), net reproduction rate (R₀), mean generation time (T) were 0.1674 d⁻¹, 1.1822d⁻¹, 62.26 offspring/individual, and 24.68d. The net consumption rate (C₀) was 846.15, mean daily consumption rate was 51.92 eggs for females and 19.28 eggs for males. S. takahashii exhibited type III functional response when offered T. urticae deutonymphs. Based on the random predator equation, the estimated maximum attack rate (a) and handling time (Th) were 0.1376h⁻¹ and 0.7883h. In addition, a life table experiment was conducted to evaluate the offspring sex allocation and population dynamic of Tetranychus ludeni Zacher under group-rearing conditions with different sex ratios. All bisexual groups produced offspring with similar sex allocation patterns, which started with the majority of females, then transited during the middle of the oviposition period and turned male-biased at the end of the oviposition period.

Keywords: Scolothrips takahashii, Tetranychus urticae, Tetranychus ludeni, two-sex life table, functional response, sex allocation

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1866 Profit Efficiency and Technology Adoption of Boro Rice Production in Bangladesh

Authors: Fazlul Hoque, Tahmina Akter Joya, Asma Akter, Supawat Rungsuriyawiboon

Abstract:

Rice is the staple food in Bangladesh, and therefore, self-sufficiency in rice production remains a major concern. However, Bangladesh is experiencing insufficiency in rice production due to high production cost and low national average productivity of 2.848 ton/ha in comparison to other rice-growing countries in the world. This study aims to find out the profit efficiency and determinants of profit efficiency in Boro rice cultivation in Manikganj and Dhaka districts of Bangladesh. It also focuses on technology adoption and effect of technology adoption on profit efficiency of Boro rice cultivation in Bangladesh. The data were collected from 300 households growing Boro rice through face to face interviews by one set structured questionnaire; Frontier Version 4.1 and STATA 15 software were employed to analyze the data according to the purpose of the study. Maximum likelihood estimates of the specified profit model showed that profit efficiency of the farmer varied between 23% and 97% with a mean of 76% which implied as 24% of the profit is lost due to a combination of technical and allocative inefficiencies in Boro rice cultivation in the study area. The inefficiency model revealed that the education level of the farmer, farm size, variety of seed, and training and extension service influence the profit inefficiency significantly. The study also explained that the level of technology adoption index affects profit efficiency. The technology adoption in Boro rice cultivation is influenced by the education level of the farmer, farm size and farm capital.

Keywords: farmer, maximum likelihood estimation, profit efficiency, rice

Procedia PDF Downloads 139
1865 Comparative Fragility Analysis of Shallow Tunnels Subjected to Seismic and Blast Loads

Authors: Siti Khadijah Che Osmi, Mohammed Ahmad Syed

Abstract:

Underground structures are crucial components which required detailed analysis and design. Tunnels, for instance, are massively constructed as transportation infrastructures and utilities network especially in urban environments. Considering their prime importance to the economy and public safety that cannot be compromised, thus any instability to these tunnels will be highly detrimental to their performance. Recent experience suggests that tunnels become vulnerable during earthquakes and blast scenarios. However, a very limited amount of studies has been carried out to study and understanding the dynamic response and performance of underground tunnels under those unpredictable extreme hazards. In view of the importance of enhancing the resilience of these structures, the overall aims of the study are to evaluate probabilistic future performance of shallow tunnels subjected to seismic and blast loads by developing detailed fragility analysis. Critical non-linear time history numerical analyses using sophisticated finite element software Midas GTS NX have been presented about the current methods of analysis, taking into consideration of structural typology, ground motion and explosive characteristics, effect of soil conditions and other associated uncertainties on the tunnel integrity which may ultimately lead to the catastrophic failure of the structures. The proposed fragility curves for both extreme loadings are discussed and compared which provide significant information the performance of the tunnel under extreme hazards which may beneficial for future risk assessment and loss estimation.

Keywords: fragility analysis, seismic loads, shallow tunnels, blast loads

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1864 The Impact of Life Satisfaction on Substance Abuse: Delinquency as a Mediator

Authors: Mahadzirah Mohamad, Morliyati Mohammad, Nor Azman Mat Ali, Zainudin Awang

Abstract:

Globally, youth substance abuse has been identified as the problem that causes substantial damage not only to individuals, but also to families and communities. In addition, substance abuse youths have become unproductive resources that would play lesser roles in the nation’s development. The increasing trend of substance abuse among youths has raised a lot of concern among various quarters in Malaysia. It has also been reported that Malay youths are the majority group involved in substance abuse. However, it was noted that life satisfaction had been found to be an important mitigating factor that addressed substance abuse. The objectives of the study were twofold: firstly, to ascertain the effect of life satisfaction on substance abuse among Malay youth. Secondly, to identify the role of delinquency on the relationship between life satisfaction and substance abuse. This study adopted a cross-sectional research design. Self-administered questionnaires were distributed to 500 Malay youths at the youth programmes using a two-step sampling technique: area sampling and systematic sampling. The research hypotheses were tested using Structural Equation Modelling. The findings of the study revealed that there is no significance relationship between life satisfaction and substance abuse. There is a significant inverse relationship between life satisfaction and delinquency. Moreover, delinquency has a positive significant influence on substance abuse. The use of Bootstrapping analysis proved that delinquency plays a full mediating role in the relationship between life satisfaction and substance abuse. This study suggested that life satisfaction has no effect on youth substance abuse. In order to reduce substance abuse, efforts should be undertaken to reduce delinquency behaviour by increasing youth life satisfaction.

Keywords: delinquency, life satisfaction, substance abuse, youth

Procedia PDF Downloads 356
1863 Validation of SWAT Model for Prediction of Water Yield and Water Balance: Case Study of Upstream Catchment of Jebba Dam in Nigeria

Authors: Adeniyi G. Adeogun, Bolaji F. Sule, Adebayo W. Salami, Michael O. Daramola

Abstract:

Estimation of water yield and water balance in a river catchment is critical to the sustainable management of water resources at watershed level in any country. Therefore, in the present study, Soil and Water Assessment Tool (SWAT) interfaced with Geographical Information System (GIS) was applied as a tool to predict water balance and water yield of a catchment area in Nigeria. The catchment area, which was 12,992km2, is located upstream Jebba hydropower dam in North central part of Nigeria. In this study, data on the observed flow were collected and compared with simulated flow using SWAT. The correlation between the two data sets was evaluated using statistical measures, such as, Nasch-Sucliffe Efficiency (NSE) and coefficient of determination (R2). The model output shows a good agreement between the observed flow and simulated flow as indicated by NSE and R2, which were greater than 0.7 for both calibration and validation period. A total of 42,733 mm of water was predicted by the calibrated model as the water yield potential of the basin for a simulation period 1985 to 2010. This interesting performance obtained with SWAT model suggests that SWAT model could be a promising tool to predict water balance and water yield in sustainable management of water resources. In addition, SWAT could be applied to other water resources in other basins in Nigeria as a decision support tool for sustainable water management in Nigeria.

Keywords: GIS, modeling, sensitivity analysis, SWAT, water yield, watershed level

Procedia PDF Downloads 446
1862 Estimation of Asphalt Pavement Surfaces Using Image Analysis Technique

Authors: Mohammad A. Khasawneh

Abstract:

Asphalt concrete pavements gradually lose their skid resistance causing safety problems especially under wet conditions and high driving speeds. In order to enact the actual field polishing and wearing process of asphalt pavement surfaces in a laboratory setting, several laboratory-scale accelerated polishing devices were developed by different agencies. To mimic the actual process, friction and texture measuring devices are needed to quantify surface deterioration at different polishing intervals that reflect different stages of the pavement life. The test could still be considered lengthy and to some extent labor-intensive. Therefore, there is a need to come up with another method that can assist in investigating the bituminous pavement surface characteristics in a practical and time-efficient test procedure. The purpose of this paper is to utilize a well-developed image analysis technique to characterize asphalt pavement surfaces without the need to use conventional friction and texture measuring devices in an attempt to shorten and simplify the polishing procedure in the lab. Promising findings showed the possibility of using image analysis in lieu of the labor-sensitive-variable-in-nature friction and texture measurements. It was found that the exposed aggregate surface area of asphalt specimens made from limestone and gravel aggregates produced solid evidence of the validity of this method in describing asphalt pavement surfaces. Image analysis results correlated well with the British Pendulum Numbers (BPN), Polish Values (PV) and Mean Texture Depth (MTD) values.

Keywords: friction, image analysis, polishing, statistical analysis, texture

Procedia PDF Downloads 309
1861 Religious Tourism the Core Strategy of Shaping Life Style: Evidences from Iran

Authors: Mostafa Jafari

Abstract:

Religious tourism is the core strategy of shaping Iranian's life-style. Why and How? This paper answers to this question. Theoretical base: From strategic marketing point of view, Life style is pattern of believes values, interests and acts. Strategy can be defined as a set of continuous important decisions. Here, strategy is making decisions about the target place and vehicle of touristic travel due to reform and redefine the self-identity and shaping life style. Methodology: Target society of this research is the selected residents of three provinces at northwest of Iran. The data collection instrument is interview and questionnaire and the collected data analysis by SEM (structural Equation Modeling) and LISREL software. Results: The primary results show that variety of touristic travels play an important role on shaping new life style of Iranian people. The target places of touristic travel (Europe, USA. Japan and etc.) are at the second priority. The number of foreign friends is at the third position. The fourth criteria are the number of travels. Among all kind of touristic travels the religious tourism from competitive point of view plays the main role. Findings: The geometry of Iranian life style are shaping and reshaping through some domestic and international tourism strategies particular religious strategy. During the dynamic trend of identity redefine, so many Iranians put the quantity and quality of their touristic travel on the first priority.

Keywords: religious tourism, core strategy, shaping life style

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1860 Evaluation Criteria for Performance of Knitted Terry Fabrics and Building Elements of Fashion: A Critical Review

Authors: Harpinder Kaur, Amit Madahar

Abstract:

The terry fabric is one of the fastest growing and challenging sub-sectors of the textile industry. Terry fabrics are produced using ground weft, ground warp, and pile yarns. The terry fabrics not only finds applications in towels but also in home textile products, sauna dressing- gowns, slippers, jackets, garments, apparels, outerwears, overcoats, sweatshirts, children’s clothes, and hygiene products for babies, beachwear, sleepwear, gloves, scarfs, shawls, etc. In some cases, these wide ranges of applications not only demand a high degree of absorption but also necessitate the due consideration for the handle properties of the fabrics. These fabrics are required to be accessed for their performance in terms of absorbency and comfort characteristics. Since material (yarns, colors, fabrics, fashion, patrons, accessories and fittings) are the core elements of structure of fashion, hence textile and fashion go hand in hand. This paper throws some light on the performance evaluation of terry fabrics. Here, characteristics/features that are required to be achieved for satisfactory performance of the terry fabrics with reference to fashion are discussed. The terry fabrics are being modified over the years in terms of the raw material requirements such as 100% cotton or blends or cotton with other fibers in order to obtain better performance as well as their structural parameters including stitch length and stitch density etc.

Keywords: absorbency, comfort, cotton, performance, terry fabrics, fashion

Procedia PDF Downloads 150