Search results for: high strain rate
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 25705

Search results for: high strain rate

21145 Process of Dimensioning Small Type Annular Combustors

Authors: Saleh B. Mohamed, Mohamed H. Elhsnawi, Mesbah M. Salem

Abstract:

Current and future applications of small gas turbine engines annular type combustors have requirements presenting difficult disputes to the combustor designer. Reduced cost and fuel consumption and improved durability and reliability as well as higher temperatures and pressures for such application are forecast. Coupled with these performance requirements, irrespective of the engine size, is the demand to control the pollutant emissions, namely the oxides of nitrogen, carbon monoxide, smoke and unburned hydrocarbons. These technical and environmental challenges have made the design of small size combustion system a very hard task. Thus, the main target of this work is to generalize a calculation method of annular type combustors for small gas turbine engines that enables to understand the fundamental concepts of the coupled processes and to identify the proper procedure that formulates and solves the problems in combustion fields in as much simplified and accurate manner as possible. The combustion chamber in task is designed with central vaporizing unit and to deliver 516.3 KW of power. The geometrical constraints are 142 mm & 140 mm overall length and casing diameter, respectively, while the airflow rate is 0.8 kg/sec and the fuel flow rate is 0.012 kg/sec. The relevant design equations are programmed by using MathCAD language for ease and speed up of the calculation process.

Keywords: design of gas turbine, small engine design, annular type combustors, mechanical engineering

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21144 Statistical Data Analysis of Migration Impact on the Spread of HIV Epidemic Model Using Markov Monte Carlo Method

Authors: Ofosuhene O. Apenteng, Noor Azina Ismail

Abstract:

Over the last several years, concern has developed over how to minimize the spread of HIV/AIDS epidemic in many countries. AIDS epidemic has tremendously stimulated the development of mathematical models of infectious diseases. The transmission dynamics of HIV infection that eventually developed AIDS has taken a pivotal role of much on building mathematical models. From the initial HIV and AIDS models introduced in the 80s, various improvements have been taken into account as how to model HIV/AIDS frameworks. In this paper, we present the impact of migration on the spread of HIV/AIDS. Epidemic model is considered by a system of nonlinear differential equations to supplement the statistical method approach. The model is calibrated using HIV incidence data from Malaysia between 1986 and 2011. Bayesian inference based on Markov Chain Monte Carlo is used to validate the model by fitting it to the data and to estimate the unknown parameters for the model. The results suggest that the migrants stay for a long time contributes to the spread of HIV. The model also indicates that susceptible individual becomes infected and moved to HIV compartment at a rate that is more significant than the removal rate from HIV compartment to AIDS compartment. The disease-free steady state is unstable since the basic reproduction number is 1.627309. This is a big concern and not a good indicator from the public heath point of view since the aim is to stabilize the epidemic at the disease equilibrium.

Keywords: epidemic model, HIV, MCMC, parameter estimation

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21143 Preparation of Catalyst-Doped TiO2 Nanotubes by Single Step Anodization and Potential Shock

Authors: Hyeonseok Yoo, Kiseok Oh, Jinsub Choi

Abstract:

Titanium oxide nanotubes have attracted great attention because of its photocatalytic activity and large surface area. For enhancing electrochemical properties, catalysts should be doped into the structure because titanium oxide nanotubes themselves have low electroconductivity and catalytic activity. It has been reported that Ru and Ir doped titanium oxide electrodes exhibit high efficiency and low overpotential in the oxygen evolution reaction (OER) for water splitting. In general, titanium oxide nanotubes with high aspect ratio cannot be easily doped by conventional complex methods. Herein, two types of facile routes, namely single step anodization and potential shock, for Ru doping into high aspect ratio titanium oxide nanotubes are introduced in detail. When single step anodization was carried out, stability of electrodes were increased. However, onset potential was shifted to anodic direction. On the other hand, when high potential shock voltage was applied, a large amount of ruthenium/ruthenium oxides were doped into titanium oxide nanotubes and thick barrier oxide layers were formed simultaneously. Regardless of doping routes, ruthenium/ ruthenium oxides were homogeneously doped into titanium oxide nanotubes. In spite of doping routes, doping in aqueous solution generally led to incorporate high amount of Ru in titanium oxide nanotubes, compared to that in non-aqueous solution. The amounts of doped catalyst were analyzed by X-ray photoelectron spectroscopy (XPS). The optimum condition for water splitting was investigated in terms of the amount of doped Ru and thickness of barrier oxide layer.

Keywords: doping, potential shock, single step anodization, titanium oxide nanotubes

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21142 Advanced Nanostructured Materials and Their Application for Solar Fuel

Authors: A. Hegazy, Ahmed Elsayed, Essam El Shenawy, N. Allam, Hala Handal, K. R. Mahmoud

Abstract:

Highly crystalline, TiO₂ pristine sub-10 nm anatase nanocrystals were fabricated at low temperatures by post hydrothermal treatment of the as-prepared TiO₂ nanoparticles. This treatment resulted in bandgap narrowing and increased photocurrent density value (3.8 mA/cm²) when this material was employed in water splitting systems. The achieved photocurrent values are among the highest reported ones so far for the fabricated nanoparticles at this low temperature. This might be explained by the increased surface defects of the prepared nanoparticles. It resulted in bandgap narrowing that was further investigated using positron annihilation experiments by measuring positron lifetime and Doppler broadening. Besides, homogeneous spherical TiO₂ nanoparticles were synthesized in large diameter and high surface area and the high percentage of (001) facet by sol-gel method using potassium persulfate (K₂S₂O₈) as an oxidizing agent. The fabricated particles exhibited high exposed surface area, high photoactivity and reduced band gap. Enhanced performance for water splitting applications was displayed by formed TiO₂ nanoparticles. Their morphological and structural properties were studied to optimize their synthesis parameters in an attempt to construct more applicable fuel cells in the industry for hydrogen fuel production.

Keywords: positron annihilation, solar energy, TiO2 nanoparticles, water splitting

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21141 Experimental-Numerical Inverse Approaches in the Characterization and Damage Detection of Soft Viscoelastic Layers from Vibration Test Data

Authors: Alaa Fezai, Anuj Sharma, Wolfgang Mueller-Hirsch, André Zimmermann

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Viscoelastic materials have been widely used in the automotive industry over the last few decades with different functionalities. Besides their main application as a simple and efficient surface damping treatment, they may ensure optimal operating conditions for on-board electronics as thermal interface or sealing layers. The dynamic behavior of viscoelastic materials is generally dependent on many environmental factors, the most important being temperature and strain rate or frequency. Prior to the reliability analysis of systems including viscoelastic layers, it is, therefore, crucial to accurately predict the dynamic and lifetime behavior of these materials. This includes the identification of the dynamic material parameters under critical temperature and frequency conditions along with a precise damage localization and identification methodology. The goal of this work is twofold. The first part aims at applying an inverse viscoelastic material-characterization approach for a wide frequency range and under different temperature conditions. For this sake, dynamic measurements are carried on a single lap joint specimen using an electrodynamic shaker and an environmental chamber. The specimen consists of aluminum beams assembled to adapter plates through a viscoelastic adhesive layer. The experimental setup is reproduced in finite element (FE) simulations, and frequency response functions (FRF) are calculated. The parameters of both the generalized Maxwell model and the fractional derivatives model are identified through an optimization algorithm minimizing the difference between the simulated and the measured FRFs. The second goal of the current work is to guarantee an on-line detection of the damage, i.e., delamination in the viscoelastic bonding of the described specimen during frequency monitored end-of-life testing. For this purpose, an inverse technique, which determines the damage location and size based on the modal frequency shift and on the change of the mode shapes, is presented. This includes a preliminary FE model-based study correlating the delamination location and size to the change in the modal parameters and a subsequent experimental validation achieved through dynamic measurements of specimen with different, pre-generated crack scenarios and comparing it to the virgin specimen. The main advantage of the inverse characterization approach presented in the first part resides in the ability of adequately identifying the material damping and stiffness behavior of soft viscoelastic materials over a wide frequency range and under critical temperature conditions. Classic forward characterization techniques such as dynamic mechanical analysis are usually linked to limitations under critical temperature and frequency conditions due to the material behavior of soft viscoelastic materials. Furthermore, the inverse damage detection described in the second part guarantees an accurate prediction of not only the damage size but also its location using a simple test setup and outlines; therefore, the significance of inverse numerical-experimental approaches in predicting the dynamic behavior of soft bonding layers applied in automotive electronics.

Keywords: damage detection, dynamic characterization, inverse approaches, vibration testing, viscoelastic layers

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21140 Orthopedic Trauma in Newborn Babies

Authors: Joanna Maj, Awais Hussain, Lyndsey Vu, Catherine Roxas

Abstract:

Background: Bone injuries in babies are common conditions that arise during delivery. Fractures of the clavicle, humerus, femur, and skull are the most common neonatal bone injuries sustained from labor and delivery. During operative deliveries, zealous tractions, ineffective delivery techniques, improper uterine incision, and inadequate relaxation of the uterus can lead to bone fractures in the newborn. Neonatal anatomy is unique. Just as children are not mini-adults, newborns are not mini children. A newborn’s anatomy and physiology are significantly different from a pediatric patient's. In this paper, we describe common orthopedic trauma in newborn babies. We provide a comprehensive overview of the different types of bone injuries in newborns. We hypothesize that the rate of bone fractures sustained at birth is higher in cases of operative deliveries. Methods: Relevant literature was selected by using the PubMed database. Search terms included orthopedic conditions in newborns, neonatal anatomy, and bone fractures in neonates during operative deliveries. Inclusion criteria included age, gender, race, type of bone injury and progression of bone injury. Exclusion criteria were limited in the medical history of cases reviewed and comorbidities. Results: This review finds that a clavicle fracture is the most common type of neonatal orthopedic injury sustained at birth in both operative and non-operative deliveries. We confirm the hypothesis that infants born via operative deliveries have a significantly higher rate of bone fractures than non-cesarean section deliveries. Conclusion: Newborn babies born via operative deliveries have a higher rate of bone fractures of the clavicle, humerus, and femur. A clavicle bone fracture in newborns is most common during emergency operative deliveries in new mothers. We conclude that infants born via an operative delivery sustained more bone injuries than infants born via non-cesarean section deliveries.

Keywords: clavicle fracture, humerus fracture, neonates, newborn orthopedics, orthopedic surgery, pediatrics, orthopedic trauma, orthopedic trauma during delivery, cesarean section, obstetrics, neonatal anatomy, neonatal fractures, operative deliveries, labor and delivery, bone injuries in neonates

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21139 Two-wavelength High-energy Cr:LiCaAlF6 MOPA Laser System for Medical Multispectral Optoacoustic Tomography

Authors: Radik D. Aglyamov, Alexander K. Naumov, Alexey A. Shavelev, Oleg A. Morozov, Arsenij D. Shishkin, Yury P.Brodnikovsky, Alexander A.Karabutov, Alexander A. Oraevsky, Vadim V. Semashko

Abstract:

The development of medical optoacoustic tomography with the using human blood as endogenic contrast agent is constrained by the lack of reliable, easy-to-use and inexpensive sources of high-power pulsed laser radiation in the spectral region of 750-900 nm [1-2]. Currently used titanium-sapphire, alexandrite lasers or optical parametric light oscillators do not provide the required and stable output characteristics, they are structurally complex, and their cost is up to half the price of diagnostic optoacoustic systems. Here we are developing the lasers based on Cr:LiCaAlF6 crystals which are free of abovementioned disadvantages and provides intensive ten’s ns-range tunable laser radiation at specific absorption bands of oxy- (~840 nm) and -deoxyhemoglobin (~757 nm) in the blood. Cr:LiCAF (с=3 at.%) crystals were grown in Kazan Federal University by the vertical directional crystallization (Bridgman technique) in graphite crucibles in a fluorinating atmosphere at argon overpressure (P=1500 hPa) [3]. The laser elements have cylinder shape with the diameter of 8 mm and 90 mm in length. The direction of the optical axis of the crystal was normal to the cylinder generatrix, which provides the π-polarized laser action correspondent to maximal stimulated emission cross-section. The flat working surfaces of the active elements were polished and parallel to each other with an error less than 10”. No any antireflection coating was applied. The Q-switched master oscillator-power amplifiers laser system (MOPA) with the dual-Xenon flashlamp pumping scheme in diffuse-reflectivity close-coupled head were realized. A specially designed laser cavity, consisting of dielectric highly reflective reflectors with a 2 m-curvature radius, a flat output mirror, a polarizer and Q-switch sell, makes it possible to operate sequentially in a circle (50 ns - laser one pulse after another) at wavelengths of 757 and 840 nm. The programmable pumping system from Tomowave Laser LLC (Russia) provided independent to each pulses (up to 250 J at 180 μs) pumping to equalize the laser radiation intensity at these wavelengths. The MOPA laser operates at 10 Hz pulse repetition rate with the output energy up to 210 mJ. Taking into account the limitations associated with physiological movements and other characteristics of patient tissues, the duration of laser pulses and their energy allows molecular and functional high-contrast imaging to depths of 5-6 cm with a spatial resolution of at least 1 mm. Highly likely the further comprehensive design of laser allows improving the output properties and realizing better spatial resolution of medical multispectral optoacoustic tomography systems.

Keywords: medical optoacoustic, endogenic contrast agent, multiwavelength tunable pulse lasers, MOPA laser system

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21138 A Qualitative Study on Metacognitive Patterns among High and Low Performance Problem Based on Learning Groups

Authors: Zuhairah Abdul Hadi, Mohd Nazir bin Md. Zabit, Zuriadah Ismail

Abstract:

Metacognitive has been empirically evidenced to be one important element influencing learning outcomes. Expert learners engage in metacognition by monitoring and controlling their thinking, and listing, considering and selecting the best strategies to achieve desired goals. Studies also found that good critical thinkers engage in more metacognition and people tend to activate more metacognition when solving complex problems. This study extends past studies by performing a qualitative analysis to understand metacognitive patterns among two high and two low performing groups by carefully examining video and audio records taken during Problem-based learning activities. High performing groups are groups with majority members scored well in Watson Glaser II Critical Thinking Appraisal (WGCTA II) and academic achievement tests. Low performing groups are groups with majority members fail to perform in the two tests. Audio records are transcribed and analyzed using schemas adopted from past studies. Metacognitive statements are analyzed using three stages model and patterns of metacognitive are described by contexts, components, and levels for each high and low performing groups.

Keywords: academic achievement, critical thinking, metacognitive, problem-based learning

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21137 Analyzing Risk and Expected Return of Lenders in the Shared Mortgage Program of Korea

Authors: Keunock Lew, Seungryul Ma

Abstract:

The paper analyzes risk and expected return of lenders who provide mortgage loans to households in the shared mortgage program of Korea. In 2013, the Korean government introduced the mortgage program to help low income householders to convert their renting into purchasing houses. The financial source for the mortgage program is the Urban Housing Fund set up by the Korean government. Through the program, low income households can borrow money from lenders to buy a house at a very low interest rate (e.g. 1 % per year) for a long time. The motivation of adopting this mortgage program by the Korean government is that the cost of renting houses has been rapidly increased especially in large urban areas during the past decade, which became financial difficulties to low income households who do not have their own houses. As the analysis methodology, the paper uses a spread sheet model for projecting cash flows of the mortgage product over the period of loan contract. It also employs Monte Carlo simulation method to analyze the risk and expected yield of the lenders with assumption that the future housing price and market rate of interest follow a stochastic process. The study results will give valuable implications to the Korean government and lenders who want to stabilize the mortgage program and innovate the related loan products.

Keywords: expected return, Monte Carlo simulation, risk, shared mortgage program

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21136 Properties of Hot-Pressed Alumina-Graphene Composites

Authors: P. Rutkowski, G. Górny, L. Stobierski, D. Zientara, W. Piekarczyk, K. Tran

Abstract:

The polycrystalline dense alumina shows thermal conductivity about 30 W/mK and very high electrical resistivity. These last two properties can be modified by introducing commercial relatively cheap graphene nanoparticles which, as two-dimensional flakes show very high thermal and electrical properties. The aim of this work is to show that it is possible to manufacture the anisotropic alumina-graphene material with directed multilayer graphene particles. Such materials can show the anisotropic properties mentioned before.

Keywords: alumina, composite, hot-pressed, graphene, properties

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21135 Multi-Objective Evolutionary Computation Based Feature Selection Applied to Behaviour Assessment of Children

Authors: F. Jiménez, R. Jódar, M. Martín, G. Sánchez, G. Sciavicco

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Abstract—Attribute or feature selection is one of the basic strategies to improve the performances of data classification tasks, and, at the same time, to reduce the complexity of classifiers, and it is a particularly fundamental one when the number of attributes is relatively high. Its application to unsupervised classification is restricted to a limited number of experiments in the literature. Evolutionary computation has already proven itself to be a very effective choice to consistently reduce the number of attributes towards a better classification rate and a simpler semantic interpretation of the inferred classifiers. We present a feature selection wrapper model composed by a multi-objective evolutionary algorithm, the clustering method Expectation-Maximization (EM), and the classifier C4.5 for the unsupervised classification of data extracted from a psychological test named BASC-II (Behavior Assessment System for Children - II ed.) with two objectives: Maximizing the likelihood of the clustering model and maximizing the accuracy of the obtained classifier. We present a methodology to integrate feature selection for unsupervised classification, model evaluation, decision making (to choose the most satisfactory model according to a a posteriori process in a multi-objective context), and testing. We compare the performance of the classifier obtained by the multi-objective evolutionary algorithms ENORA and NSGA-II, and the best solution is then validated by the psychologists that collected the data.

Keywords: evolutionary computation, feature selection, classification, clustering

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21134 Weak Instability in Direct Integration Methods for Structural Dynamics

Authors: Shuenn-Yih Chang, Chiu-Li Huang

Abstract:

Three structure-dependent integration methods have been developed for solving equations of motion, which are second-order ordinary differential equations, for structural dynamics and earthquake engineering applications. Although they generally have the same numerical properties, such as explicit formulation, unconditional stability and second-order accuracy, a different performance is found in solving the free vibration response to either linear elastic or nonlinear systems with high frequency modes. The root cause of this different performance in the free vibration responses is analytically explored herein. As a result, it is verified that a weak instability is responsible for the different performance of the integration methods. In general, a weak instability will result in an inaccurate solution or even numerical instability in the free vibration responses of high frequency modes. As a result, a weak instability must be prohibited for time integration methods.

Keywords: dynamic analysis, high frequency, integration method, overshoot, weak instability

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21133 Termination of the Brachial Artery in the Arm and Its Clinical Significance

Authors: Ramya Rathan, Miral N. F. Salama

Abstract:

The variations in the arteries have been drawing attention of anatomists for a long time because of their clinical significance. The brachial artery is the principal artery of the arm which is the continuation of the axillary artery from the lower border of the Teres Major. It terminates into the radial and ulnar arteries below the elbow joint at the neck radius. The present study aims at exploring the clinical significance of the high termination of the brachial artery. During the routine cadaveric dissection of the arm, for the undergraduate students of medicine at our university, we observed a high bifurcation of the radial and the ulnar artery at the midshaft of the humerus. The median nerve was seen passing between these two junctions. Further, the course and the relations of this artery were studied. The accurate knowledge regarding these kinds of variation in the blood vessels is mandatory for planning of designing. General physicians, surgeons and radiologists should keep in mind the variations in the branching pattern of the arteries in their daily medical, diagnostic and therapeutic procedures to avoid complications in diagnostic and surgical procedures.

Keywords: brachial artery, high termination, radial artery, ulnar artery

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21132 High Pressure Multiphase Flow Experiments: The Impact of Pressure on Flow Patterns Using an X-Ray Tomography Visualisation System

Authors: Sandy Black, Calum McLaughlin, Alessandro Pranzitelli, Marc Laing

Abstract:

Multiphase flow structures of two-phase multicomponent fluids were experimentally investigated in a large diameter high-pressure pipeline up to 130 bar at TÜV SÜD’s National Engineering Laboratory Advanced Multiphase Facility. One of the main objectives of the experimental test campaign was to evaluate the impact of pressure on multiphase flow patterns as much of the existing information is based on low-pressure measurements. The experiments were performed in a horizontal and vertical orientation in both 4-inch and 6-inch pipework using nitrogen, ExxsolTM D140 oil, and a 6% aqueous solution of NaCl at incremental pressures from 10 bar to 130 bar. To visualise the detailed structure of the flow of the entire cross-section of the pipe, a fast response X-ray tomography system was used. A wide range of superficial velocities from 0.6 m/s to 24.0 m/s for gas and 0.04 m/s and 6.48 m/s for liquid was examined to evaluate different flow regimes. The results illustrated the suppression of instabilities between the gas and the liquid at the measurement location and that intermittent or slug flow was observed less frequently as the pressure was increased. CFD modellings of low and high-pressure simulations were able to successfully predict the likelihood of intermittent flow; however, further tuning is necessary to predict the slugging frequency. The dataset generated is unique as limited datasets exist above 100 bar and is of considerable value to multiphase flow specialists and numerical modellers.

Keywords: computational fluid dynamics, high pressure, multiphase, X-ray tomography

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21131 English Language Performance and Emotional Intelligence of Senior High School Students of Pit-Laboratory High School

Authors: Sonia Arradaza-Pajaron

Abstract:

English as a second language is widely spoken in the Philippines. In fact, it is used as a medium of instruction in school. However, Filipino students, in general, are still not proficient in the use of the language. Since it plays a very crucial role in the learning and comprehension of some subjects in the school where important key concepts and in English, it is imperative to look into other factors that may affect such concern. This study may post an answer to the said concern because it aimed to investigate the association between a psychological construct, known as emotional intelligence, and the English language performance of the 55 senior high school students. The study utilized a descriptive correlational method to determine the significant relationship of variables with preliminary data, like GPA in English subject as baseline information of their performance. Results revealed that the respondents had an average GPA in the English subject; however, improving from their first-year high school level to the fourth year. Their English performance resulted to an above average level with a notable higher performance in the speaking test than in the written. Further, a strong correlation between English performance and emotional intelligence was manifested. Based on the findings, it can be concluded that students with higher emotional intelligence their English language performance is expected to be the same. It can be said further that when students’ emotional intelligence (EI components) is facilitated well through various classroom activities, a better English performance would just be spontaneous among them.

Keywords: English language performance, emotional intelligence, EI components, emotional literacy, emotional quotient competence, emotional quotient outcomes, values and beliefs

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21130 An Automated Procedure for Estimating the Glomerular Filtration Rate and Determining the Normality or Abnormality of the Kidney Stages Using an Artificial Neural Network

Authors: Hossain A., Chowdhury S. I.

Abstract:

Introduction: The use of a gamma camera is a standard procedure in nuclear medicine facilities or hospitals to diagnose chronic kidney disease (CKD), but the gamma camera does not precisely stage the disease. The authors sought to determine whether they could use an artificial neural network to determine whether CKD was in normal or abnormal stages based on GFR values (ANN). Method: The 250 kidney patients (Training 188, Testing 62) who underwent an ultrasonography test to diagnose a renal test in our nuclear medical center were scanned using a gamma camera. Before the scanning procedure, the patients received an injection of ⁹⁹ᵐTc-DTPA. The gamma camera computes the pre- and post-syringe radioactive counts after the injection has been pushed into the patient's vein. The artificial neural network uses the softmax function with cross-entropy loss to determine whether CKD is normal or abnormal based on the GFR value in the output layer. Results: The proposed ANN model had a 99.20 % accuracy according to K-fold cross-validation. The sensitivity and specificity were 99.10 and 99.20 %, respectively. AUC was 0.994. Conclusion: The proposed model can distinguish between normal and abnormal stages of CKD by using an artificial neural network. The gamma camera could be upgraded to diagnose normal or abnormal stages of CKD with an appropriate GFR value following the clinical application of the proposed model.

Keywords: artificial neural network, glomerular filtration rate, stages of the kidney, gamma camera

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21129 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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21128 Cereal Bioproducts Conversion to Higher Value Feed by Using Pediococcus Strains Isolated from Spontaneous Fermented Cereal, and Its Influence on Milk Production of Dairy Cattle

Authors: Vita Krungleviciute, Rasa Zelvyte, Ingrida Monkeviciene, Jone Kantautaite, Rolandas Stankevicius, Modestas Ruzauskas, Elena Bartkiene

Abstract:

The environmental impact of agricultural bioproducts from the processing of food crops is an increasing concern worldwide. Currently, cereal bran has been used as a low-value ingredient for both human consumption and animal feed. The most popular bioprocessing technologies for cereal bran nutritional and technological functionality increasing are enzymatic processing and fermentation, and the most popular starters in fermented feed production are lactic acid bacteria (LAB) including pediococci. However, the ruminant digestive system is unique, there are billions of microorganisms which help the cow to digest and utilize nutrients in the feed. To achieve efficient feed utilization and high milk yield, the microorganisms must have optimal conditions, and the disbalance of this system is highly undesirable. Pediococcus strains Pediococcus acidilactici BaltBio01 and Pediococcus pentosaceus BaltBio02 from spontaneous fermented rye were isolated (by rep – PCR method), identified, and characterized by their growth (by Thermo Bioscreen C automatic turbidometer), acidification rate (2 hours in 2.5 pH), gas production (Durham method), and carbohydrate metabolism (by API 50 CH test ). Antimicrobial activities of isolated pediococcus against variety of pathogenic and opportunistic bacterial strains previously isolated from diseased cattle, and their resistance to antibiotics were evaluated (EFSA-FEEDAP method). The isolated pediococcus strains were cultivated in barley/wheat bran (90 / 10, m / m) substrate, and developed supplements, with high content of valuable pediococcus, were used for Lithuanian black and white dairy cows feeding. In addition, the influence of supplements on milk production and composition was determined. Milk composition was evaluated by the LactoScope FTIR” FT1.0. 2001 (Delta Instruments, Holland). P. acidilactici BaltBio01 and P. pentosaceus BaltBio02 demonstrated versatile carbohydrate metabolism, grown at 30°C and 37°C temperatures, and acidic tolerance. Isolated pediococcus strains showed to be non resistant to antibiotics, and having antimicrobial activity against undesirable microorganisms. By barley/wheat bran utilisation using fermentation with selected pediococcus strains, it is possible to produce safer (reduced Enterobacteriaceae, total aerobic bacteria, yeast and mold count) feed stock with high content of pediococcus. Significantly higher milk yield (after 33 days) by using pediococcus supplements mix for dairy cows feeding could be obtained, while similar effect by using separate strains after 66 days of feeding could be achieved. It can be stated that barley/wheat bran could be used for higher value feed production in order to increase milk production. Therefore, further research is needed to identify what is the main mechanism of the positive action.

Keywords: barley/wheat bran, dairy cattle, fermented feed, milk, pediococcus

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21127 Protonic Conductivity Highlighted by Impedance Measurement of Y-Doped BaZrO3 Synthesized by Supercritical Hydrothermal Process

Authors: Melanie Francois, Gilles Caboche, Frederic Demoisson, Francois Maeght, Maria Paola Carpanese, Lionel Combemale, Pascal Briois

Abstract:

Finding new clean, and efficient way for energy production is one of the actual global challenges. Advances in fuel cell technology have shown that, for few years, Protonic Ceramic Fuel Cell (PCFC) has attracted much attention in the field of new hydrogen energy thanks to their lower working temperature, possible higher efficiency, and better durability than classical SOFC. On the contrary of SOFC, where O²⁻ oxygen ion is the charge carrier, PCFC works with H⁺ proton as a charge carrier. Consequently, the lower activation energy of proton diffusion compared to the one of oxygen ion explains those benefits and allows PCFC to work in the 400-600°C temperature range. Doped-BaCeO₃ is currently the most chosen material for this application because of its high protonic conductivity; for example, BaCe₀.₉Y₀.₁O₃ δ exhibits a total conductivity of 1.5×10⁻² S.cm⁻¹ at 600°C in wet H₂. However, BaCeO₃ based perovskite has low stability in H₂O and/or CO₂ containing atmosphere, which limits their practical application. On the contrary, BaZrO₃ based perovskite exhibits good chemical stability but lower total conductivity than BaCeO₃ due to its larger grain boundary resistance. By substituting zirconium with 20% of yttrium, it is possible to achieve a total conductivity of 2.5×10⁻² S.cm⁻¹ at 600°C in wet H₂. However, the high refractory property of BaZr₀.₈Y₀.₂O₃-δ (noted BZY20) causes problems to obtain a dense membrane with large grains. Thereby, using a synthesis process that gives fine particles could allow better sinterability and thus decrease the number of grain boundaries leading to a higher total conductivity. In this work, BaZr₀.₈Y₀.₂O₃-δ have been synthesized by classical batch hydrothermal device and by a continuous hydrothermal device developed at ICB laboratory. The two variants of this process are able to work in supercritical conditions, leading to the formation of nanoparticles, which could be sintered at a lower temperature. The as-synthesized powder exhibits the right composition for the perovskite phase, impurities such as BaCO₃ and YO-OH were detected at very low concentration. Microstructural investigation and densification rate measurement showed that the addition of 1 wt% of ZnO as sintering aid and a sintering at 1550°C for 5 hours give high densified electrolyte material. Furthermore, it is necessary to heat the synthesized powder prior to the sintering to prevent the formation of secondary phases. It is assumed that this thermal treatment homogenizes the crystal structure of the powder and reduces the number of defects into the bulk grains. Electrochemical impedance spectroscopy investigations in various atmospheres and a large range of temperature (200-700°C) were then performed on sintered samples, and the protonic conductivity of BZY20 has been highlighted. Further experiments on half-cell, NiO-BZY20 as anode and BZY20 as electrolyte, are in progress.

Keywords: hydrothermal synthesis, impedance measurement, Y-doped BaZrO₃, proton conductor

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21126 Utility of Thromboelastography to Reduce Coagulation-Related Mortality and Blood Component Rate in Neurosurgery ICU

Authors: Renu Saini, Deepak Agrawal

Abstract:

Background: Patients with head and spinal cord injury frequently have deranged coagulation profiles and require blood products transfusion perioperatively. Thromboelastography (TEG) is a ‘bedside’ global test of coagulation which may have role in deciding the need of transfusion in such patients. Aim: To assess the usefulness of TEG in department of neurosurgery in decreasing transfusion rates and coagulation-related mortality in traumatic head and spinal cord injury. Method and Methodology: A retrospective comparative study was carried out in the department of neurosurgery over a period of 1 year. There are two groups in this study. ‘Control’ group constitutes the patients in whom data was collected over 6 months (1/6/2009-31/12/2009) prior to installation of TEG machine. ‘Test’ group includes patients in whom data was collected over 6months (1/1/2013-30/6/2013) post TEG installation. Total no. of platelet, FFP, and cryoprecipitate transfusions were noted in both groups along with in hospital mortality and length of stay. Result: Both groups were matched in age and sex of patients, number of head and spinal cord injury cases, number of patients with thrombocytopenia and number of patients who underwent operation. Total 178 patients (135 head injury and 43 spinal cord injury patents) were admitted in neurosurgery department during time period June 2009 to December 2009 i.e. prior to TEG installation and after TEG installation a total of 243 patients(197 head injury and 46 spinal cord injury patents) were admitted. After TEG introduction platelet transfusion significantly reduced (p=0.000) compare to control group (67 units to 34 units). Mortality rate was found significantly reduced after installation (77 patients to 57 patients, P=0.000). Length of stay was reduced significantly (Prior installation 1-211days and after installation 1-115days, p=0.02). Conclusion: Bedside TEG can dramatically reduce platelet transfusion components requirement in department of neurosurgery. TEG also lead to a drastic decrease in mortality rate and length of stay in patients with traumatic head and spinal cord injuries. We recommend its use as a standard of care in the patients with traumatic head and spinal cord injuries.

Keywords: blood component transfusion, mortality, neurosurgery ICU, thromboelastography

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21125 Performance Investigation of Silica Gel Fluidized Bed

Authors: Sih-Li Chen, Chih-Hao Chen, Chi-Tong Chan

Abstract:

Poor ventilation and high carbon dioxide (CO2) concentrations lead to the formation of sick buildings. This problem cannot simply be resolved by introducing fresh air from outdoor environments because this creates extra loads on indoor air-conditioning systems. Desiccants are widely used in air conditioning systems in tropical and subtropical regions with high humidity to reduce the latent heat load from fresh air. Desiccants are usually used as a packed-bed type, which is low cost, to combine with air-conditioning systems. Nevertheless, the pressure drop of a packed bed is too high, and the heat of adsorption caused by the adsorption process lets the temperature of the outlet air increase, bringing about an extra heat load, so the high pressure drop and the increased temperature of the outlet air are energy consumption sources needing to be resolved. For this reason, the gas-solid fluidised beds that have high heat and mass transfer rates, uniform properties and low pressure drops are very suitable for use in air-conditioning systems.This study experimentally investigates the performance of silica gel fluidized bed device which applying to an air conditioning system. In the experiments, commercial silica gel particles were filled in the two beds and to form a fixed packed bed and a fluidized bed. The results indicated that compared to the fixed packed bed device, the total adsorption and desorption by amounts of fluidized bed for 40 minutes increased 20.6% and 19.9% respectively when the bed height was 10 cm and superficial velocity was set to 2 m/s. In addition, under this condition, the pressure drop and outlet air temperature raise were reduced by 36.0% and 30.0%. Given the above results, application of the silica gel fluidized bed to air conditioning systems has great energy-saving potential.

Keywords: fluidized bed, packed bed, silica gel, adsorption, desorption, pressure drop

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21124 Morphological and Biological Identification of Fusarium Species Associated with Ear Rot Disease of Maize in Indonesia and Malaysia

Authors: Darnetty Baharuddin Salleh

Abstract:

Fusarium ear rot disease is one of the most important diseases of maize and not only causes significant losses but also produced harmful mycotoxins to animals and humans. A total of 141 strains of Fusarium species were isolated from maize plants showing typical ear rot symptoms in Indonesia, and Malaysia by using the semi-selective medium (peptone pentachloronitrobenzene agar, PPA). These strains were identified morphologically. For strains in Gibberella fujikuroi species complex (Gfsc), the identification was continued by using biological identification. Three species of Fusarium were morphologically identified as Fusarium in Gibberella species complex (105 strains, 74.5%), F. verticillioides (78 strains), F. proliferatum (24 strains) and F. subglutinans (3 strains) and five species from other section (36 strains, 25.5%), F. graminearum (14 strains), F. oxysporum (8 strains), F. solani ( 1 strain), and F. semitectum (13 strains). Out of 105 Fusarium species in Gfsc, 63 strains were identified as MAT-1, 25 strains as MAT-2 and 17 strains could not be identified and in crosses with nine standard testers, three mating populations of Fusarium were identified as MP-A, G. moniliformis (68 strains, 64.76%), MP-D, G. intermedia (21 strains, 20%) and MP-E, G. subglutinans (3 strains, 2.9%), and 13 strains (12.38%) could not be identified. All trains biologically identified as MP-A, MP-D, and MP-E, were identified morphologically as F. verticillioides, F. proliferatum, and F. subglutinans, respectively. Thus, the results of this study indicated that identification based on biological identification were consistent with those of morphological identification. This is the first report on the presence of MP-A, MP-D, and MP-E on ear rot-infected maize in Indonesia; MP-A and MP-E in Malaysia.

Keywords: Fusarium, MAT-1, MAT-2, MP-A, MP-D, MP-E

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21123 Novel Spoke-Type BLDC Motor Design for Cost Effective and High Power Density

Authors: Suyong Kim

Abstract:

Recently because of the rise in the price of rare earth magnet, interest of non-rare earth or less-rare earth motor is growing. Especially to achieve the high power density, Spoke-Type BLDC (Brushless Permanent Magnet) Motor with ferrite permanent magnet are spotlighted. But Spoke-Type Ferrite BLDC Motor has much of magnetic flux leakage in the direction of rotor shaft. In order to solve this problem, there are two conventional ways. But conventional ways bring the increases of product cost or the decreases of the power density. Therefore, this paper proposes new Spoke-Type BLDC Rotor shape that has the advantages of both conventional methods. The new shape is consists of a one-piece core. The inside and the outside of the rotor are open alternately. So it can take reduced production cost and high power density.

Keywords: motor, BLDC, spoke, ferrite

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21122 Orange Peel Derived Activated Carbon /Chitosan Composite as Highly Effective and Low-Cost Adsorbent for Adsorption of Methylene Blue

Authors: Onur Karaman, Ceren Karaman

Abstract:

In this study, the adsorption of Methylene Blue (MB), a cationic dye, onto Orange Peel Derived Activated Carbon (OPAC) and chitosan(OPAC/Chitosan composite) composite (a low-cost absorbent) was carried out using a batch system. The composite was characterised using IR spectra, XRD, FESEM and Pore size studies. The effects of initial pH, adsorbent dose rate and initial dye concentration on the initial adsorption rate, capacity and dye removal efficiency were investigated. The Langmuir and Freundlich adsorption models were used to define the adsorption equilibrium of dye-adsorbent system mathematically and it was decided that the Langmuir model was more suitable to describe the adsorption equilibrium for the system. In addition, first order, second order and saturation type kinetic models were applied to kinetic data of adsorption and kinetic constants were calculated. It was concluded that the second order and the saturation type kinetic models defined the adsorption data more accurately. Finally, the evaluated thermodynamic parameters of adsorption show a spontaneous and exothermic behavior. Overall, this study indicates OPAC/Chitosan composite as an effective and low-cost adsorbent for the removal of MB dye from aqueous solutions.

Keywords: activated carbon, adsorption, chitosan, methylene blue, orange peel

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21121 The Effect of Irgafos 168 in the Thermostabilization of High Density Polyethylene

Authors: Mahdi Almaky

Abstract:

The thermostabilization of High Density Polyethylene (HDPE) is realized through the action of primary antioxidant such as phenolic antioxidants and secondary antioxidants as aryl phosphates. The efficiency of two secondary antioxidants, commercially named Irgafos 168 and Weston 399, was investigated using different physical, mechanical, spectroscopic, and calorimetric methods. The effect of both antioxidants on the processing stability and long term stability of HDPE produced in Ras Lanuf oil and gas processing Company were measured and compared. The combination of Irgafos 168 with Irganox 1010, as used in smaller concentration, results in a synergetic effect against thermo-oxidation and protect better than the combination of Weston 399 with Irganox 1010 against the colour change at processing temperature and during long term oxidation process.

Keywords: thermostabilization, high density polyethylene, primary antioxidant, phenolic antioxidant, Irgafos 168, Irganox 1010, Weston 399

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21120 Virtual Reality Technology for Employee Training in High-Risk Industries: Benefits and Advancements

Authors: Yeganeh Jabbari, Sepideh Khalatabad

Abstract:

This study explores the development of virtual reality (VR) technology for training applications, specifically its the potential benefits of VR technology for employee training and its ability to simulate real-world scenarios in a safe and controlled environment are highlighted, along with the associated cost and time savings. The adoption of VR technology in high-risk industrial organizations such as the oil and gas industry is discussed, with a focus on its ability to improve worker performance. Additionally, the use of VR technology in activities such as simulation and data visualization in the oil and gas industry is explored, leading to enhanced safety measures and collaboration between teams. The integration of advanced technologies such as robotics is mentioned as a way to further promote efficiency and sustainability. Also, the study mentions that the digital transformation of the oil and gas industry is revolutionizing operations and promoting safety, efficiency, and sustainability through the use of VR technology.

Keywords: virtual reality training, virtual reality benefits, high-risk industries, digital transformation

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21119 Diverted Use of Contraceptives in Madagascar

Authors: Josiane Yaguibou, Ngoy Kishimba, Issiaka V. Coulibaly, Sabrina Pestilli, Falinirina Razanalison, Hantanirina V. Andremanisa

Abstract:

Background In Madagascar modern contraceptive prevalence rate increased from 18% in 2003 to 43% in 2021. Anecdotal evidence suggests that increased use and frequent stock out in public health facilities of male condoms and medroxyprogesterone acetate (MPA) can be related to diverted use of these products. This study analyzed the use of contraceptives and mode of utilization (correct or diverted) at the community level in the period 2019-2023 in Madagascar. Methodology: The study included a literature review, a quantitative survey combined with a qualitative study. It was carried out in 10 regions out of the 23 of the country. Eight regions (Bongolava, Vakinakaratra, Italy, Hautre Matsiatra, Betsiboka, Diana, Sofia and Anosy) were selected based on a study that showed existence of medroxyprogesterone acetate in pigs (MPA). The remaining 2 regions were selected due to high mCPR (Atsimo Andrefana) and to ensure coverage of all geographical zones in the country (Alaotra Mangoro). Sample random method was used, and the sample size was identified at 300 individuals per region. Zonal distribution is based on the urbanization rate for the region. 6 focus group discussions were organized in 3 regions, equally distributed between rural and urban areas. Key findings: Overall, 67% of those surveyed or their partner are currently using contraception. Injectables (MPA) are the most popular choice (33%), followed by implants and male condoms, 12% and 9%, respectively. The majority of respondents use condoms to prevent unwanted pregnancy but also to prevent STDs. Still, 43% of respondents use condoms for other purposes, reaching 52% of respondents in urban areas and 71,2% in the age group 15-18. Diverted use includes hair growth (18.9%), as a toy (18.8%), cleaning the screen of electronic devices (10 %), cleaning shoes (3.1%) and for skincare (1.6%). Injectables are the preferred method of contraception both in rural areas (35%) and urban areas (21.2%). However, diverted use of injectables was confirmed by 4% of the respondents, ranging from 3 % in rural areas to 12% in urban. The diverted use of injectables in pig rearing was to avoid pregnancy and facilitate pig’s growth. Program Implications: The study confirmed the diverted use of some contraceptives. The misuse of male condoms is among the causes of stockouts of products in public health facilities, limiting their availability for pregnancy and STDs prevention. The misuse of injectables in pigs rearing needs to be further studied to learn the full extent of the misuse and eventual implications for meat consumption. The study highlights the importance of including messages on the correct use of products during sensibilization activities. In particular, messages need to address the anecdotal and false effects of male condoms, especially amongst young people. For misuse of injectables is critical to sensibilize farmers and veterinaries on possible negative effects for humans.

Keywords: diverted use, injectables, male condoms, sensibilization

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21118 Reducing the Incidence Rate of Pressure Sore in a Medical Center in Taiwan

Authors: Chang Yu Chuan

Abstract:

Background and Aim: Pressure sore is not only the consequence of any gradual damage of the skin leading to tissue defects but also an important indicator of clinical care. If hospitalized patients develop pressure sores without proper care, it would result in delayed healing, wound infection, increase patient physical pain, prolonged hospital stay and even death, which would have a negative impact on the quality of care and also increase nursing manpower and medical costs. This project is aimed at decreasing the incidence of pressure sore in one ward of internal medicine. Our data showed 53 cases (0.61%) of pressure sore in 2015, which exceeded the average (0.5%) of Taiwan Clinical Performance Indicator (TCPI) for medical centers. The purpose of this project is to reduce the incidence rate of pressure sore in the ward. After data collection and analysis from January to December 2016, the reasons of developing pressure sore were found: 1. Lack of knowledge to prevent pressure among nursing staffs; 2. No relevant courses about preventing pressure ulcers and pressure wound care being held in this unit; 3. Low complete rate of pressure sore care education that family members should receive from nursing staffs; 4. Decompression equipment is not enough; 5. Lack of standard procedures for body-turning and positioning care. After team members brainstorming, several strategies were proposed, including holding in-service education, pressure sore care seed training, purchasing decompression mattress and memory pillows, designing more elements of health education tools, such as health education pamphlet, posters and multimedia films of body-turning and positioning demonstration, formulation and promotion of standard operating procedures. In this way, nursing staffs can understand the body-turning and positioning guidelines for pressure sore prevention and enhance the quality of care. After the implementation of this project, the pressure sore density significantly decreased from 0.61%(53 cases) to 0.45%(28 cases) in this ward. The project shows good results and good example for nurses working at the ward and helps to enhance quality of care.

Keywords: body-turning and positioning, incidence density, nursing, pressure sore

Procedia PDF Downloads 253
21117 Impact of Emergency Medicine Department Crowding on Mortality

Authors: Morteza Gharibi, Abdolghader Pakniat, Somayeh Bahrampouri

Abstract:

Introduction: Emergency department (E.R.) crowding is a serious widespread problem in hospitals that leads to irregularities, a slower rate of delivery of services to patients, and a long-term stay. In addition, the long-term stay in the E.D. reduces the possibility of providing services with appropriate quality to other patients who are undergoing medical emergencies, which leads to dissatisfaction among patients. This study aimed to determine the relationship between ED-crowding and the mortality rate of the patients referred to the E.D. In a retrospective cohort study, all patients who expired in first 24 hours of admission were enrolled in the study. Crowding index at the moment of admission was calculated using Edwin Score. The data including history and physical examination, time of arrival in the E.D., diagnosis (using ICD 10 code), time of death, cause of death, demographic information was recoded based on triage forms on admission and patients’ medical files. Data analysis was performed by using descriptive statistics and chi square test, ANOVA tests using SPSS ver. 19. The time of arrival in E.D. to death in crowded E.D. conditions, with an average of five hours and 25 minutes, was significantly higher than the average admission Time of arrival in E.D. to death in active and crowded E.D. conditions. More physicians and nurses can be employed during crowded times to reduce staff fatigue and improve their performance during these hours.

Keywords: mortality, emergency, department, crowding

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21116 The Coexistence of Dual Form of Malnutrition among Portuguese Institutionalized Elderly People

Authors: C. Caçador, M. J. Reis Lima, J. Oliveira, M. J. Veiga, M. Teixeira Veríssimo, F. Ramos, M. C. Castilho, E. Teixeira-Lemos

Abstract:

In the present study we evaluated the nutritional status of 214 institutionalized elderly residents of both genders, aged 65 years and older of 11 care homes located in the district of Viseu (center of Portugal). The evaluation was based on anthropometric measurements and the Mini Nutritional Assessment (MNA) score. The mean age of the subjects was 82.3 ± 6.1 years-old. Most of the elderly residents were female (72.0%). The majority had 4 years of formal education (51.9%) and was widowed (74.3%) or married (14.0%). Men presented a mean age of 81.2±8.5 years-old, weight 69.3±14.5 kg and BMI 25.33±6.5 kg/m2. In women, the mean age was 84.5±8.2 years-old, weight 61.2±14.7 kg and BMI 27.43±5.6 kg/m2. The evaluation of the nutritional status using the MNA score showed that 24.0% of the residents show a risk of undernutrition and 76.0% of them were well nourished. There was a high prevalence of obese (24.8%) and overweight residents (33.2%) according to the BMI. 7.5% were considered underweight. We also found that according to their waist circumference measurements 88.3% of the residents were at risk for cardiovascular disease (CVD) and 64.0% of them presented very high risk for CVD (WC≥88 cm for women and WC ≥102 cm for men). The present study revealed the coexistence of a dual form of malnutrition (undernourished and overweight) among the institutionalized Portuguese concomitantly with an excess of abdominal adiposity. The high prevalence of residents at high risk for CVD should not be overlooked. Given the vulnerability of the group of institutionalized elderly, our study highlights the importance of the classification of nutritional status based on both instruments: the BMI and the MNA.

Keywords: nutritional satus, MNA, BMI, elderly

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