Search results for: physical vapor deposition coating method

Authors: Taboka Motlhabane, Pradeep Sahoo

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The global demand for cooling has grown exponentially over the past century to meet economic development and social needs, accounting for approximately 10% of the global electricity consumption. As global temperatures continue to rise, the demand for cooling and heating, ventilation and air-conditioning (HVAC) equipment is set to rise with it. The increased use of HVAC equipment has significantly contributed to the growth of greenhouse gas (GHG) emissions which aid the climate crisis- one of the biggest challenges faced by the current generation. The need to address emissions caused directly by HVAC equipment and electricity generated to meet the cooling or heating demand is ever more pressing. Currently, developed countries account for the largest cooling and heating demand, however developing countries are anticipated to experience a huge increase in population growth in 10 years, resulting in a shift in energy demand. Developing countries, which are projected to account for nearly 60% of the world's GDP by 2030, are rapidly building infrastructure and economies to meet their growing needs and meet these projections. Cooling, a very energy-intensive process that can account for 20 % to 75% of a building's energy, depending on the building's use. Solar photovoltaic (PV) driven air-conditioning offers a great cost-effective alternative for adoption in both residential and non-residential buildings to offset grid electricity, particularly in countries with high irradiation, such as Botswana. This research paper explores the potential of a grid-connected solar photovoltaic vapor-compression air-conditioning system for the Peter-Smith herbarium at the Okavango Research Institute (ORI) University of Botswana campus in Maun, Botswana. The herbarium plays a critical role in the collection and preservation of botanical data, dating back over 100 years, with pristine collection from the Okavango Delta, a UNESCO world heritage site and serves as a reference and research site. Due to the herbarium’s specific needs, it operates throughout the day and year in an attempt to maintain a constant herbarium temperature of 16°?. The herbarium model studied simulates a variable-air-volume HVAC system with a system rating of 30 kW. Simulation results show that the HVAC system accounts for 68.9% of the building's total electricity at 296 509.60 kWh annually. To offset the grid electricity, a 175.1 kWp nominal power rated PV system requiring 416 modules to match the required power, covering an area of 928 m2 is used to meet the HVAC system annual needs. An economic assessment using PVsyst found that for an installation priced with average solar PV prices in Botswana totalled to be 787 090.00 BWP, with annual operating costs of 30 500 BWP/year. With self-project financing, the project is estimated to have recouped its initial investment within 6.7 years. At an estimated project lifetime of 20 years, the Net Present Value is projected at 1 565 687.00 BWP with a ROI of 198.9%, with 74 070.67 tons of CO2 saved at the end of the project lifetime. This study investigates the performance of the HVAC system to meet the indoor air comfort requirements, the annual PV system performance, and the building model has been simulated using DesignBuilder Software.

Keywords: vapor compression refrigeration, solar cooling, renewable energy, herbarium

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Authors: Potaliya Pushpa, Kataria Sushma, D. S. Chowdhary, Dadhich Abhilasha

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Introduction: Stress is a nonspecific response of the body to a stressor or triggering stimulus. Chronic stress exposure contributes to various remarkable alterations o growth and development. Collective effects of stressors lead to several changes which are physical, physiological and behavioral in nature. Objective: To understand on an animal model how various chronic stress affect the somatic body growth as it can be useful for effective stress treatment and prevention of stress related illnesses. Material and Method: By selective fostering only male pup colonies were made and 102 male albino rats were studied. They were divided two groups as Control and Stressed. The experimental groups were exposed to four major types of stress as maternal deprivation, Restraint stress, electric foot shock and noise stress for affecting emotional, physical and physiological activities. Exposure was from birth to 17 week of life. Roentgenographs were taken in two planes as Dorso-ventral and Lateral and then measured for each rat. Various parameters were observed at specific intervals. Parameters recorded were Body weight and for linear growth it was summation of Cranial length, Head rump length and tail length. Behavior changes were also observed. Result: Multiple chronic stresses resulted in loss of approx. 25% of mean body weight. Maximal difference was found on 119th day (i.e. 87.81 gm) between the control and stressed group. Linear growth showed retardation which was found to be significant in stressed group on statistical analysis. Cranial Length and Head-rump Length showed maximum difference after maternal deprivation stress. After maternal deprivation (Day 21) and electric foot shock (Day 101) maximum difference i.e. 0.39 cm and 0.47 cm were found in cranial length of two groups. Electric foot shock had considerable impact on tail length. Noise Stress affected moreover behavior as compact to physical growth. Conclusion: Collective study showed that chronic stress not only resulted in reduced body weight in albino rats but also total linear size of rat thus affecting whole growth and development.

Keywords: stress, microscopic anatomy, macroscopic anatomy, chronic multiple stress, birth

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Authors: Raquel P. F. Guiné, Marlene I. C. Tenreiro, Ana C. Correia, Paulo Barracosa, Paula M. R. Correia

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The objective of this study was to evaluate the physical and chemical characteristics of Serra da Estrela cheese and compare these results with those of the sensory analysis. For the study were taken six samples of Serra da Estrela cheese produced with 6 different ecotypes of thistle in a dairy situated in Penalva do Castelo. The chemical properties evaluated were moisture content, protein, fat, ash, chloride and pH; the physical properties studied were color and texture; and finally a sensory evaluation was undertaken. The results showed moisture varying in the range 40-48%, protein in the range 15-20%, fat between 41-45%, ash between 3.9-5.0% and chlorides varying from 1.2 to 3.0%. The pH varied from 4.8 to 5.4. The textural properties revealed that the crust hardness is relatively low (maximum 7.3 N), although greater than flesh firmness (maximum 1.7 N), and also that these cheeses are in fact soft paste type, with measurable stickiness and intense adhesiveness. The color analysis showed that the crust is relatively light (L* over 50), and with a predominant yellow coloration (b* around 20 or over) although with a slight greenish tone (a* negative). The results of the sensory analysis did not show great variability for most of the attributes measured, although some differences were found in attributes such as crust thickness, crust uniformity, and creamy flesh.

Keywords: chemical composition, color, sensorial analysis, Serra da Estrela cheese, texture

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Authors: Freddy Rodriguez Saza, Erika Sanabria, Jair Tibana

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Currently, the important role of neurosciences in the professional training of the physical educator is known, highlighting in the teaching-learning process aspects such as the nervous structures involved in the adjustment of posture and movement, the neurophysiology of locomotion, the process of nerve impulse transmission, and the relationship between physical activity, learning, and cognition. The teaching-learning process of neurosciences is complex, due to the breadth of the contents, the diversity of teaching contexts required, and the demanding ability to relate concepts from different disciplines, necessary for the correct understanding of the function of the nervous system. This text presents the results of the application of a didactic environment based on the Allosteric Learning Model in morphophysiology students of the Faculty of Military Physical Education, Military School of Cadets of the Colombian Army (Bogotá, Colombia). The research focused then, on analyzing the change in the cognitive structure of the students on neurosciences. Methodology. [1] The predominant learning styles were identified. [2] Students' cognitive structure, core concepts, and threshold concepts were analyzed through the construction of Pathfinder Associative Networks. [3] Didactic Units in Neuroscience were designed to favor metacognition, the development of Executive Functions (working memory, cognitive flexibility, and inhibitory control) that led students to recognize their errors and conceptual distortions and to overcome them. [4] The Teacher's Professional Knowledge and the role of the assessment strategies applied were taken into account, taking into account the perspective of the Dynamizer, Obstacle, and Questioning axes. In conclusion, the study found that physical education students achieved significant learning in neuroscience, favored by the development of executive functions and by didactic environments oriented with the predominant learning styles and focused on increasing cognitive networks and overcoming difficulties, neuromyths and neurophobia.

Keywords: allosteric learning model, military physical education, neurosciences, pathfinder associative networks, teacher professional knowledge

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Authors: Aditya Manna, L. K. Khanra, S. K. Sarkar

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Aim: Due to financial incapability and the absence of manpower-poor families often fail to carry their advanced cancer patients to the nodal centers. This pilot study will explore whether communication by mobile phone can lessen this burden. Method: Initially a plan was generated regarding management of an advanced cancer patient in a nodal center at District Head Quarter. Subsequently every two week a trained social worker attached to the nodal center will follow up and give necessary advice and emotional support to the patients and their families through their registered mobile phone number. Patient’s family were also encouraged to communicate with the team by phone in case of fresh complain and urgency in between. Results: Since initiation in January 2013, 193 cancer patients were contacted by mobile phone every two weeks to enquire about their difficulties. In 76% of the situation trained social workers could give necessary advice by phone regarding management of their physical symptoms. Moreover, patient’s family was really overwhelmed by the emotional support offered by the team over the phone. Only 24% of cancer patients have to attend the nodal center for expert advice from Palliative Care specialists. Conclusion: This novel approach helped: (a) In providing regular physical and emotional support to the patients and their families. (b) In significantly reducing the financial and manpower problems of carrying patients to the nodal units. (c) In improving the quality of life of patients by continuous guidance. More and more team members can take help of this new strategy for better communication and uninterrupted care.

Keywords: palliative care, terminal care, home based palliative care, rural india

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Authors: Salisu Ibrahim

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The paper studies the commutativity associated with fractional order linear time-varying systems (LTVSs), which is an important area of study in control systems engineering. In this paper, we explore the properties of these systems and their ability to commute. We proposed the necessary and sufficient condition for commutativity for fractional order LTVSs. Through a simulation and mathematical analysis, we demonstrate that these systems exhibit commutativity under certain conditions. Our findings have implications for the design and control of fractional order systems in practical applications, science, and engineering. An example is given to show the effectiveness of the proposed method which is been computed by Mathematica and validated by the use of MATLAB (Simulink).

Keywords: fractional differential equation, physical systems, equivalent circuit, analog control

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Authors: T. Kritsana, P. Sawitri, P. Teeratas

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This article aims to study the effect of pressure on rocket motor case by Finite Element Method simulation to select optimal material in rocket motor manufacturing process. In this study, cylindrical tubes with outside diameter of 122 mm and thickness of 3 mm are used for simulation. Defined rocket motor case materials are AISI4130, AISI1026, AISI1045, AL2024 and AL7075. Internal pressure used for the simulation is 22 MPa. The result from Finite Element Method shows that at a pressure of 22 MPa rocket motor case produced by AISI4130, AISI1045 and AL7075 can be used. A comparison of the result between AISI4130, AISI1045 and AL7075 shows that AISI4130 has minimum principal stress and confirm the results of Finite Element Method by the used of calculation method found that, the results from Finite Element Method has good reliability.

Keywords: rocket motor case, finite element method, principal stress, simulation

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Authors: Ansah Iris Baffour, Dong-Ho Kim, Sung-Gyu Park

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The ongoing COVID-19 pandemic, caused by the SARS-CoV-2 virus and is gradually shifting to an endemic phase which implies the outbreak is far from over and will be difficult to eradicate. Global cooperation has led to unified precautions that aim to suppress epidemiological spread (e.g., through travel restrictions) and reach herd immunity (through vaccinations); however, the primary strategy to restrain the spread of the virus in mass populations relies on screening protocols that enable rapid on-site diagnosis of infections. Herein, we employed surface enhanced Raman spectroscopy (SERS) for the rapid detection of SARS-CoV-2 lysate on an Au-modified Au nanodimple(AuND)electrode. Through in situone-pot Au electrodeposition on the AuND electrode, Au-lysate nanocomposites were synthesized, generating3D internal hotspots for large SERS signal enhancements within 30 s of the deposition. The capture of lysate into newly generated plasmonic nanogaps within the nanocomposite structures enhanced metal-spike protein contact in 3D spaces and served as hotspots for sensitive detection. The limit of detection of SARS-CoV-2 lysate was 5 x 10-2 PFU/mL. Interestingly, ultrasensitive detection of the lysates of influenza A/H1N1 and respiratory syncytial virus (RSV) was possible, but the method showed ultimate selectivity for SARS-CoV-2 in lysate solution mixtures. We investigated the practical application of the approach for rapid on-site diagnosis by detecting SARS-CoV-2 lysate spiked in normal human saliva at ultralow concentrations. The results presented demonstrate the reliability and sensitivity of the assay for rapid diagnosis of COVID-19.

Keywords: label-free detection, nanocomposites, SARS-CoV-2, surface-enhanced raman spectroscopy

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Authors: Syauqi Asfiya R.

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This study examines the constraints faced by Islamic boarding school (Pesantren) in Indonesia in effectively addressing physical violence within their educational institutions. The vulnerability to violence in the education sector remains pervasive, including in Pesantren, primarily due to the residential nature of the boarding school system, which necessitates round-the-clock interaction among students from diverse backgrounds. Additionally, environmental factors, parenting styles, individual characteristics, and media influences further complicate the conditions within Pesantren. Numerous cases of physical violence have been reported, underscoring the need to identify the constraints of violence prevention strategies implemented by Pesantren. Adopting a case study approach, this research focuses on a Modern Pesantren in Tangerang and utilizes interviews conducted with 20 victims of violence to explore the aspects of Pesantren's violence prevention strategies that may have been overlooked. The findings indicate that many students face a dilemma when reporting the violence they experience, as the imposed sanctions often prove excessively severe and carry the risk of exacerbating the violence perpetrated by the offenders. Consequently, numerous victims choose to remain silent, thereby enabling the perpetuation of violence. Moreover, senior students (mudabbir) are prohibited from giving punishment, but there are still many who punish other students based on their personal moods. Furthermore, violence is also perpetrated by religious teachers (ustadz), despite their responsibility for addressing such issues. The evaluation process often follows a unidirectional approach wherein the santri have limited freedom compared to the Mudabbir or ustadz when it comes to providing feedback. Additionally, sentiment within specific student generations is reinforced due to the segregation of dormitories based on cohorts. Lastly, the absence of psychologists to address the trauma experienced by victims further exacerbates the situation. This research sheds light on the constraints faced by Pesantren in effectively preventing physical violence and emphasizes the importance of implementing comprehensive measures to create safer and nurturing learning environments within these institutions.

Keywords: physical violence, islam, boarding school, constraint

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Authors: Elaine Yee Sing Wong, Jonine Jancey, Andy H. Lee, Anthony P. James

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Singapore has a rapidly aging population, where the majority of older women aged 50 years and above, are physically inactive and have unhealthy dietary habits, placing them at ‘high risk’ of non-communicable diseases. Given the multiplicity of less than optimal dietary habits and high levels of physical inactivity among Singaporean women, it is imperative to develop appropriate lifestyle interventions at recreational centres to enhance both their physical and nutritional knowledge, as well as provide them with the opportunity to develop skills to support behaviour change. To the best of our knowledge, this proposed study is the first physical activity and nutrition cluster randomised controlled trial conducted in Singapore for older women. Findings from this study may provide insights and recommendations for policy makers and key stakeholders to create new healthy living, recreational centres with supportive environments. This 6-month community-based cluster randomised controlled trial will involve the implementation and evaluation of physical activity and nutrition program for community dwelling Singaporean women, who currently attend recreational centres to promote social leisure activities in their local neighbourhood. The intervention will include dietary education and counselling sessions, physical activity classes, and telephone contact by certified fitness instructors and qualified nutritionists. Social Cognitive Theory with Motivational Interviewing will inform the development of strategies to support health behaviour change. Sixty recreational centres located in Singapore will be randomly selected from five major geographical districts and randomly allocated to the intervention (n=30) or control (n=30) cluster. A sample of 600 (intervention n=300; control n=300) women aged 50 years and above will then be recruited from these recreational centres. The control clusters will only undergo pre and post data collection and will not receive the intervention. It is hypothesised that by the end of the intervention, the intervention group participants (n = 300) compared to the control group (n = 300), will show significant improvements in the following variables: lipid profile, body mass index, physical activity and dietary behaviour, anthropometry, mental and physical health. Data collection will be examined and compared via the Statistical Package for the Social Science version 23. Descriptive and summary statistics will be used to quantify participants’ characteristics and outcome variables. Multi-variable mixed regression analyses will be used to confirm the effects of the proposed health intervention, taking into account the repeated measures and the clustering of the observations. The research protocol was approved by the Curtin University Human Research Ethics Committee (approval number: HRE2016-0366). The study has been registered with the Australian and New Zealand Clinical Trial Registry (12617001022358).

Keywords: community based, healthy aging, intervention, nutrition, older women, physical activity

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Authors: H. Fazlinejad, A. Halvaee

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In this study, characteristics of ATIG welds using ZnO flux on aluminum was investigated and compared with TIG welds. Autogenously AC-ATIG bead on plate welding was applied on Al1050 plate with a coating of ZnO as the flux. Different levels of welding current and flux layer thickness was considered to study the effect of heat input and flux quantity on ATIG welds and was compared with those of TIG welds. Geometrical investigation of the weld cross sections revealed that penetration depth of the ATIG welds with ZnO flux, was increased up to 2 times in some samples compared to the TIG welds. Optical metallographic and Scanning Electron Microscopy (SEM) observations revealed similar microstructures in TIG and ATIG welds. Composition of the ATIG welds slag was also analyzed using X-ray diffraction. In both TIG and ATIG samples, the lowest values of microhardness were observed in the HAZ.

Keywords: ATIG, active flux, weld penetration, Al 1050, ZnO

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Authors: John Vergara, Giuseppe Palmese

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Fundamental studies aimed at elucidating the key contributions to corrosion performance are needed to make progress toward effective and environmentally compliant corrosion control. Epoxy/amine systems are typically employed as barrier coatings for corrosion control. However, the hardening agents used for coating applications can be very complex, making fundamental studies of water and oxygen permeability challenging to carry out. Creating model building blocks for epoxy/amine coatings is the first step in carrying out these studies. We will demonstrate the synthesis and characterization of model amine building blocks from saturated fatty acids and simple amines such as diethylenetriamine (DETA) and Bis(3-aminopropyl)amine. The structure-property relationship of thermosets made from these model amines and Diglycidyl ether of bisphenol A (DGBEA) will be discussed.

Keywords: building block, amine, synthesis, characterization

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Authors: Meriem Hamla, Mohamed Benaicha, Sabrine Derbal

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In the present work, several materials such as M/glass (M = Pt, Mo) were investigated to test their suitability for studying the early nucleation stages and growth of copper-tin clusters. It was found that most of these materials stand as good substrates to be used in the study of the nucleation and growth of electrodeposited Cu-Sn alloys from aqueous solution containing CuCl2, SnCl2 as electroactive species and Na3C6H5O7 as complexing agent. Among these substrates, Pt shows instantaneous models followed by 3D diffusion-limited growth. On the other hand, the electrodeposited copper-tin thin films onto Mo substrate followed progressive nucleation. The deposition mechanism of the Cu-Sn films has been studied using stationary electrochemical techniques (cyclic voltammetery (CV) and chronoamperometry (CA). The structural, morphological and compositional of characterization have been studied using X-ray diffraction (XRD), scanning electron microscopy (SEM) and EDAX techniques respectively.

Keywords: electrodeposition, CuSn, nucleation, mechanism

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Authors: Mohammad Ghandehari Motlagh

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Purpose: Comparing anterior chamber depth (ACD) measured with Orbscan II and Pentacam HR compared with the Smith method results. Methods: Smith method (1979) is a reliable method of measuring ACD only with help of slit lamp. In this study 102 phakic eyes as PRK candidates were imaged with both OrbScan and Pentacam and finally ACD was measured thru Smith method with slit lamp. ACD measured with Smith method was presumed as the gold standard and was compared with ACD of the 2 imaging devices. Contraindication cases for PRK and pseudophakic eyes have been excluded from the study. Results: Mean age of the patients was 35.2 ±14.8 yrs/old including 56 M(54.9%)and 46 F(45.09%).Acceptable correlation of ACD measured thru Smith method with Orbscan and Pentacam are R=0.958 and R=0.942 respectively and so Orbscan results can be used in procedures relying on ACD. Conclusion: ACDs measured with OrbScan is more precise than Pentacam and so can be more useful in some surgery procedures relying ACD results such as phakic IOLs and in cycloplegia contraindications.

Keywords: orbscan, pentacam, anterior chamber depth, slit lamp

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Authors: Salisu Ibrahim

Abstract:

The paper studies the commutativity associated with fractional order linear time-varying systems (LTVSs), which is an important area of study in control systems engineering. In this paper, we explore the properties of these systems and their ability to commute. We proposed the necessary and sufficient condition for commutativity for fractional order LTVSs. Through a simulation and mathematical analysis, we demonstrate that these systems exhibit commutativity under certain conditions. Our findings have implications for the design and control of fractional order systems in practical applications, science, and engineering. An example is given to show the effectiveness of the proposed method which is been computed by Mathematica and validated by the use of Matlab (Simulink).

Keywords: fractional differential equation, physical systems, equivalent circuit, and analog control

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Authors: M. Tang, S. M. Wen, D. W. Liu

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This paper presents the influences on the entrainment of serpentines by grinding and reagents during copper–nickel sulfide flotation. The previous bench flotation tests were performed to extract the metallic values from the ore in Yunnan Mine, China and the relatively satisfied results with recoveries of 86.92% Cu, 54.92% Ni, and 74.73% Pt+Pd in the concentrate were harvested at their grades of 4.02%, 3.24% and 76.61 g/t, respectively. However, the content of MgO in the concentrate was still more than 19%. Micro-flotation tests were conducted with the objective of figuring out the influences on the entrainment of serpentines into the concentrate by particle size, flocculants or depressants and collectors, as well as visual observations in suspension by OLYMPUS camera. All the tests results pointed to the presences of both “entrapped-in” serpentines and its coating on the hydrophobic flocs resulted from strong collectors (combination of butyl xanthate, butyl ammonium dithophosphate, even after adding carboxymethyl cellulose as effective depressant. And fine grinding may escalate the entrainment of serpentines in the concentrate.

Keywords: serpentine, copper and nickel sulfides, flotation, entrainment

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Authors: Valeria Bondarenko

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We proposed algorithms for: estimation of parameters fBm (volatility and Hurst exponent) and for the approximation of random time series by functional of fBm. We proved the consistency of the estimators, which constitute the above algorithms, and proved the optimal forecast of approximated time series. The adequacy of estimation algorithms, approximation, and forecasting is proved by numerical experiment. During the process of creating software, the system has been created, which is displayed by the hierarchical structure. The comparative analysis of proposed algorithms with the other methods gives evidence of the advantage of approximation method. The results can be used to develop methods for the analysis and modeling of time series describing the economic, physical, biological and other processes.

Keywords: mathematical model, random process, Wiener process, fractional Brownian motion

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Authors: Hrishikesh Purandare, Ashwini Pethe

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Research from developed countries has demonstrated that the built environment can have a significant effect on children’s cognitive and socio-emotional development. A majority of the studies on the relationship between the built environment and the well-being of children have been conducted in North America and Western Europe, though most of the world’s children live in the global South. Millions of children living in urban slums in India confront issues associated with poor living conditions and lack of access to basic services. It is a well-known fact that slums are places of extreme poverty, substandard housing, overcrowding, and poor sanitation. These challenges faced by children living in slums can have a significant impact on their physical, psychological, and social development. Despite the magnitude of the problem, the area of research, particularly on the impact of the built environment of slums on children and adolescent well-being, has been understudied in India. Only a few studies in the global South have investigated the impact of the built environment on children’s well-being. Apart from issues of the limited access to health and education of these children, the perception of children regarding the built environment which they inhabit is rarely addressed. A sample of 120 children living in the slums of Pune city between the ages 7 and 16 participated in this study, which employed a concurrent embedded approach of mixed method research. Questionnaires were administered to obtain quantitative data that included attributes of crowding, noise, privacy, territoriality and housing quality in the built environment. The qualitative analysis of children’s sketches highlighted aspects of the built environment with which they associated themselves the most. The study sought to examine the perception of the deprived children living in the urban slums in the city of Pune (India) towards their built environment.

Keywords: physical environment, poverty, underprivileged children, urban Indian slums

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Authors: S. Abdullahi, M. Momoh, K. U. Isah

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Zinc oxide (ZnO) thin films of 75.5 nm and 130.5 nm were deposited at room temperature onto chemically and ultrasonically cleaned corning glass substrate by radio frequency technique and annealed at 150°C under nitrogen atmosphere for 60 minutes. The optical properties of the films were ascertained by UV-VIS-NIR spectrophotometry. Influence of the thickness of the films on the optical properties was studied keeping other deposition parameters constant. The optical transmittance spectra reveal a maximum transmittance of 81.49% and 84.26% respectively. The band gap of the films is found to be direct allowed transition and decreases with the increase in thickness of the films. The band gap energy (Eg) is in the range of 3.28 eV to 3.31 eV, respectively. These thin films are suitable for solar cell applications.

Keywords: optical constants, RF sputtering, Urbach energy, zinc oxide thin film

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Authors: Wong Ka Fai

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Introduction: Many students are worried before an examination; that is a common picture worldwide. Health problems from stress before examination were insomnia, tiredness, isolation, stomach upset, and anxiety. Nursing students experienced high stress from the examination. Guided imagery is a healing process of applying imagination to help the body heal, survive, or live well. It can bring about significant physiological and biochemical changes, which can trigger the recovery process. A study of nursing students improving their anxiety before examination with guided imagery was proposed. Aim: The aim of this study was to explore the outcome of guided imagery on nursing students’ anxiety before examination in Hong Kong. Method: The qualitative study method was used. 16 first-year students studying nursing programme were invited to practice guided imagery to improve their anxiety before the examination period. One week before the examination, the semi-structured interviews with these students were carried out by the researcher. Result: From the content analysis of interview data, these nursing students showed considerable similarities in their anxiety perception. Nursing students’ perceived improved anxiety was evidenced by a reduction of stressful feelings, improved physical health, satisfaction with daily activities, and enhanced skills for solving problems and upcoming situations. Conclusion: This study indicated that guided imagery can be used as an alternative measure to improve students’ anxiety and psychological problems.

Keywords: nursing students, perception, anxiety, guided imagery

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Authors: Mahmoud Lot

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In this article, we will discuss the solution of elliptic optimal control problem. First, by using the nite element method, we obtain the discrete form of the problem. The obtained discrete problem is actually a large scale constrained optimization problem. Solving this optimization problem with traditional methods is difficult and requires a lot of CPU time and memory. But split Bergman method converts the constrained problem to an unconstrained, and hence it saves time and memory requirement. Then we use the split Bregman method for solving this problem, and examples show the speed and accuracy of split Bregman methods for solving these types of problems. We also use the SQP method for solving the examples and compare with the split Bregman method.

Keywords: Split Bregman Method, optimal control with elliptic partial differential equation constraint, finite element method

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Authors: Nada Jasim Habeeb, Rana Saad Mohammed, Muntaha Khudair Abbass

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For more efficient and fast video summarization, this paper presents a surveillance video summarization method. The presented method works to improve video summarization technique. This method depends on temporal differencing to extract most important data from large video stream. This method uses histogram differencing and Sum Conditional Variance which is robust against to illumination variations in order to extract motion objects. The experimental results showed that the presented method gives better output compared with temporal differencing based summarization techniques.

Keywords: temporal differencing, video summarization, histogram differencing, sum conditional variance

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Authors: M. Y. Waziri, M. A. Aliyu

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The paper proposes an approach to improve the performance of Broyden’s method for solving systems of nonlinear equations. In this work, we consider the information from two preceding iterates rather than a single preceding iterate to update the Broyden’s matrix that will produce a better approximation of the Jacobian matrix in each iteration. The numerical results verify that the proposed method has clearly enhanced the numerical performance of Broyden’s Method.

Keywords: mulit-step Broyden, nonlinear systems of equations, computational efficiency, iterate

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Authors: A. Azizi, S. Laidoudi, G. Schmerber, A. Dinia

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Cuprous oxide (Cu2O) is a well-known oxide semiconductor with a band gap of 2.1 eV and a natural p-type conductivity, which is an attractive material for device applications because of its abundant availability, non toxicity, and low production cost. It has a higher absorption coefficient in the visible region and the minority carrier diffusion length is also suitable for use as a solar cell absorber layer and it has been explored in junction with n type ZnO for photovoltaic applications. Cu2O nanostructures have been made by a variety of techniques; the electrodeposition method has emerged as one of the most promising processing routes as it is particularly provides advantages such as a low-cost, low temperature and a high level of purity in the products. In this work, Cu2O nanostructures prepared by electrodeposition from aqueous cupric sulfate solution with citric acid at 65°C onto a fluorine doped tin oxide (FTO) coated glass substrates were investigated. The effects of deposition potential on the electrochemical, surface morphology, structural and optical properties of Cu2O thin films were investigated. During cyclic voltammetry experiences, the potential interval where the electrodeposition of Cu2O is carried out was established. The Mott–Schottky (M-S) plot demonstrates that all the films are p-type semiconductors, the flat-band potential and the acceptor density for the Cu2O thin films are determined. AFM images reveal that the applied potential has a very significant influence on the surface morphology and size of the crystallites of thin Cu2O. The XRD measurements indicated that all the obtained films display a Cu2O cubic structure with a strong preferential orientation of the (111) direction. The optical transmission spectra in the UV-Visible domains revealed the highest transmission (75 %), and their calculated gap values increased from 1.93 to 2.24 eV, with increasing potentials.

Keywords: Cu2O, electrodeposition, Mott–Schottky plot, nanostructure, optical properties, XRD

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Authors: I. Ahumada, L. Ascar, C. Pedraza, J. Montecino

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It has been found that the addition of biosolids to soil is beneficial to soil health, enriching soil with essential nutrient elements. Although this sludge has properties that allow for the improvement of the physical features and productivity of agricultural and forest soils and the recovery of degraded soils, they also contain trace elements, organic trace and pathogens that can cause damage to the environment. The application of these biosolids to land without the total reclamation and the treated wastewater can transfer these compounds into terrestrial and aquatic environments, giving rise to potential accumulation in plants. The general aim of this study was to evaluate the bioavailability of bisphenol A (BPA), and 17 α-ethynyl estradiol (EE2) in a soil-biosolid system using wheat (Triticum aestivum) plant assays and a predictive extraction method using a solution of hydroxypropyl-β-cyclodextrin (HPCD) to determine if it is a reliable surrogate for this bioassay. Two soils were obtained from the central region of Chile (Lo Prado and Chicauma). Biosolids were obtained from a regional wastewater treatment plant. The soils were amended with biosolids at 90 Mg ha-1. Soils treated with biosolids, spiked with 10 mgkg-1 of the EE2 and 15 mgkg-1 and 30 mgkg-1of BPA were also included. The BPA, and EE2 concentration were determined in biosolids, soils and plant samples through ultrasound assisted extraction, solid phase extraction (SPE) and gas chromatography coupled to mass spectrometry determination (GC/MS). The bioavailable fraction found of each one of soils cultivated with wheat plants was compared with results obtained through a cyclodextrin biosimulator method. The total concentration found in biosolid from a treatment plant was 0.150 ± 0.064 mgkg-1 and 12.8±2.9 mgkg-1 of EE2 and BPA respectively. BPA and EE2 bioavailability is affected by the organic matter content and the physical and chemical properties of the soil. The bioavailability response of both compounds in the two soils varied with the EE2 and BPA concentration. It was observed in the case of EE2, the bioavailability in wheat plant crops contained higher concentrations in the roots than in the shoots. The concentration of EE2 increased with increasing biosolids rate. On the other hand, for BPA, a higher concentration was found in the shoot than the roots of the plants. The predictive capability the HPCD extraction was assessed using a simple linear correlation test, for both compounds in wheat plants. The correlation coefficients for the EE2 obtained from the HPCD extraction with those obtained from the wheat plants were r= 0.99 and p-value ≤ 0.05. On the other hand, in the case of BPA a correlation was not found. Therefore, the methodology was validated with respect to wheat plants bioassays, only in the EE2 case. Acknowledgments: The authors thank FONDECYT 1150502.

Keywords: emerging compounds, bioavailability, biosolids, endocrine disruptors

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Authors: Daniel Nigusse Tollosa, Erica James, Alexis Hurre, Meredith Tavener

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Introduction: Lifestyle behaviours such as healthy diet, regular physical activity and maintaining a healthy weight are essential for cancer survivors to improve the quality of life and longevity. However, there is no study that synthesis cancer survivor’s adherence to healthy lifestyle recommendations. The purpose of this review was to collate existing data on the prevalence of adherence to healthy behaviours and produce the pooled estimate among adult cancer survivors. Method: Multiple databases (Embase, Medline, Scopus, Web of Science and Google Scholar) were searched for relevant articles published since 2007, reporting cancer survivors adherence to more than two lifestyle behaviours based on the WCRF/AICR recommendations. The pooled prevalence of adherence to single and multiple behaviours (operationalized as adherence to more than 75% (3/4) of health behaviours included in a particular study) was calculated using a random effects model. Subgroup analysis adherence to multiple behaviours was undertaken corresponding to the mean survival years and year of publication. Results: A total of 3322 articles were generated through our search strategies. Of these, 51 studies matched our inclusion criteria, which presenting data from 2,620,586 adult cancer survivors. The highest prevalence of adherence was observed for smoking (pooled estimate: 87%, 95% CI: 85%, 88%) and alcohol intake (pooled estimate 83%, 95% CI: 81%, 86%), and the lowest was for fiber intake (pooled estimate: 31%, 95% CI: 21%, 40%). Thirteen studies were reported the proportion of cancer survivors (all used a simple summative index method) to multiple healthy behaviours, whereby the prevalence of adherence was ranged from 7% to 40% (pooled estimate 23%, 95% CI: 17% to 30%). Subgroup analysis suggest that short-term survivors ( < 5 years survival time) had relatively a better adherence to multiple behaviours (pooled estimate: 31%, 95% CI: 27%, 35%) than long-term ( > 5 years survival time) cancer survivors (pooled estimate: 25%, 95% CI: 14%, 36%). Pooling of estimates according to the year of publication (since 2007) also suggests an increasing trend of adherence to multiple behaviours over time. Conclusion: Overall, the adherence to multiple lifestyle behaviors was poor (not satisfactory), and relatively, it is a major concern for long-term than the short-term cancer survivor. Cancer survivors need to obey with healthy lifestyle recommendations related to physical activity, fruit and vegetable, fiber, red/processed meat and sodium intake.

Keywords: adherence, lifestyle behaviours, cancer survivors, WCRF/AICR

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Authors: Aidoud Assia, Bencheikh Messaouda, Boukour Salima

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Polystyrene is often seen in the ocean and on Algerian beaches, mainly as food containers. It's one of the top 10 most common items found there. This happens because it's light and easily carried away from its original source, like packaging or transport, into the environment. Unfortunately, it's not recycled much because it's not very profitable to do so. Hence, turning this waste into a resource can turn challenges into opportunities for a territory's economic and environmental development, which is the focus of this study. the goal is to analyze the physical and mechanical properties of a new type of mortar made from dune sand mixed with recycled polystyrene. it also aim to assess its potential for use in various construction applications. The mixtures were prepared by replacing portions of dune sand with polystyrene waste at varying volumes (10%, 20%, and 30%), while keeping the amount of cement constant. The results indicate a noticeable impact on both the physical and mechanical properties because of incorporating polystyrene waste.

Keywords: polystyrène, eco-mortier, sable de dune, résistance

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Authors: Wu Di, Yeo Khoon Seng, Lim Tee Tai

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The typical insects employ a flapping-wing mode of flight. The numerical simulations on free flight of a model fruit fly (Re=143) including hovering and are presented in this paper. Unsteady aerodynamics around a flapping insect is studied by solving the three-dimensional Newtonian dynamics of the flyer coupled with Navier-Stokes equations. A hybrid-grid scheme (Generalized Finite Difference Method) that combines great geometry flexibility and accuracy of moving boundary definition is employed for obtaining flow dynamics. The results show good points of agreement and consistency with the outcomes and analyses of other researchers, which validate the computational model and demonstrate the feasibility of this computational approach on analyzing fluid phenomena in insect flight. The present modeling approach also offers a promising route of investigation that could complement as well as overcome some of the limitations of physical experiments in the study of free flight aerodynamics of insects. The results are potentially useful for the design of biomimetic flapping-wing flyers.

Keywords: free hovering flight, flapping wings, fruit fly, insect aerodynamics, leading edge vortex (LEV), computational fluid dynamics (CFD), Navier-Stokes equations (N-S), fluid structure interaction (FSI), generalized finite-difference method (GFD)

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Authors: Tohru Kawabe

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In this paper, a new SMC (Sliding Mode Control) method with MP (Model Predictive Control) integral action for the slip suppression of EV (Electric Vehicle) under braking is proposed. The proposed method introduce the integral term with standard SMC gain , where the integral gain is optimized for each control period by the MPC algorithms. The aim of this method is to improve the safety and the stability of EVs under braking by controlling the wheel slip ratio. There also include numerical simulation results to demonstrate the effectiveness of the method.

Keywords: sliding mode control, model predictive control, integral action, electric vehicle, slip suppression

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Authors: Nargess Fasihmardanloo

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The aim of this study was to comparatively study the motivations of women to physical activity in Iran and selected Arab countries Based on individual, social and Islamic components. The present study was a descriptive comparative study that was performed by field method. The statistical population of the study included female athletes in Iran and Arab countries. A total of 184 people from Iran and 179 people from Arab countries (Iraq, UAE, and Jordan) were selected through available sampling as a research sample. The research tool included a questionnaire. The validity of the questionnaire was confirmed and its reliability in a pilot study was 0.95 through Cronbach's alpha. The questionnaire was translated into Persian in Iran and translated into Arabic for the selected countries and was provided to the participants electronically and through cyberspace. Finally, 363 questionnaires were collected. Manova multivariate analysis of variance using spss22 software was used to analyze the data. Findings showed that between Iranian women athletes and women athletes in selected Arab countries in the components of intrapersonal motivation (p = 0.009 and f = 6.978), interpersonal motivation (p = 0.050 and f = 3.875), There is a significant difference between social motives (p = 0.001 and f = 27.619) and Islamic motives (p = 0.001 and f = 11.339). And this difference is significant at the level of p <0.01 and p <0.05. In other words, in the component of intrapersonal motivations, the average of this component in Iranian female athletes (M = 59.77) was higher than female athletes in selected Arab countries (M = 55.53). In the interpersonal motivations component, the average of this component in Iranian female athletes (M = 26.87) was lower than in female athletes in selected Arab countries (M = 28.62). In the component of social motivations, the average of this component in Iranian female athletes (M = 33.08) was lower than female athletes in selected Arab countries (M = 39.64). In the component of Islamic motives, the average of this component in Iranian female athletes (M = 21.55) was higher than female athletes in selected Arab countries (M = 19.04).

Keywords: athletes, motivation, women, Islamic

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