Search results for: energy challenges

Authors: Hannah Evangeline Sangeetha

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Ageing is an inevitable change in the life span of an individual. India’s old age population has increased from 19 million in 1947 to 100 million in the 21st century. The United Nations World Population ageing reports that the grey population has immensely increased from 9.2% in 1990 to 11.7 % in 2013, and it’s expected to triple by the year 2050 growing from 737 million to over 2 billion persons 60 years of age and older. Ageing is a period of physical, mental and social decline which brings a host of challenges to the individual and the family. Hence it requires attention at the micro, mezzo and the macro levels of the society. The concepts of healthy and successful aging are being used to help people to change their negative attitude towards aging. This perspective is important to make people realize their potentialities to bring about a change in the minds of senior citizens as well as the society. The objective of this study was to understand the level of active ageing among the rural elderly women and its impact on the quality of life. 330 elderly women from 12 villages of Sriperumbudur associated with the Mobile medical care of Help age India were interviewed using census method. The study revealed the following findings; most respondents in this study were young old between the age group of 60 to 75 years. All the three major religious groups were represented, 85.5percent were Hindus. Majority of the respondents 73.3percent had no education. It was interesting to know that majority of the respondents were self reliant (83.94 percent) and 82.73 percent of them very independent and took care of them by themselves (activities of daily living) without any support from their families. 76.9 percent of the senior women worked based on their competencies, 75.5 percent of them were involved in plenty of activities everyday including their occupation and household chores, which enabled them to be physically active. The chi square values that there is a significant association between the overall active ageing score, religion &number of members in the family. The other demographic variables like age, occupation, income marital status, age at marriage, number of children in the family and Socio –Economic Status were not significantly associated with the overall active aging score. The p-value 0.032 showed Social network and being self-reliant are significantly associated. The study surprisingly shows that most women enjoyed freedom and Independence in their family which is a positive indicator of active ageing.

Keywords: active ageing, quality of life, independence, self reliance

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Authors: Gabi N. Nehme

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Below-knee amputees commonly experience asymmetrical gait patterns. It is generally believed that ischemia is related to the formation of pressure sores due to uneven distribution of forces. Micro-vascular responses can reveal local malnutrition. Changes in local skin blood supply under various external loading conditions have been studied for a number of years. Radionuclide clearance, photo-plethysmography, trans-cutaneous oxygen tension along with other studies showed that the blood supply would be influenced by the epidermal forces, and the rate and the amount of blood supply would decrease with increased epidermal loads being shear forces or normal forces. Several cases of socket designs were investigated using Finite Element Model (FEM) and Design of Experiment (DOE) to increase flexibility and minimize the pressure at the limb/socket interface using ultra high molecular weight polyethylene (UHMWPE) and polyamide 6 (PA6) or Duraform. The pressure reliefs at designated areas where reducing thickness is involved are seen to be critical in determination of amputees’ comfort and are very important to clinical applications. Implementing a hole between the Patellar Tendon (PT) and Distal Tibia (DT) would decrease stiffness and increase prosthesis range of motion where flexibility is needed. In addition, displacement and prosthetic energy storage increased without compromising mechanical efficiency and prosthetic design integrity.

Keywords: patellar tendon, distal tibia, prosthetic socket relief areas, hole implementation

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Authors: A. D. Loureiro, L. Ventura

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Exposure to high-energy blue light has been strongly linked to the development of some eye diseases, such as age-related macular degeneration. Over the past few years, people have become more and more concerned about eye damage from blue light and how it can be prevented. We developed a prototype that allows users to self-check the blue light protection of their sunglasses and determines if the protection is adequate. Weighting functions approximating those defined in ISO 12312-1 were used to measure the luminous transmittance and blue light transmittance of sunglasses. The blue light transmittance value must be less than 1.2 times the luminous transmittance to be considered adequate. The prototype consists of a Golden Dragon Ultra White LED from OSRAM and a TCS3472 photodetector from AMS TAOS. Together, they provide four transmittance values weighted with different functions. These four transmittance values were then linearly combined to produce transmittance values with weighting functions close to those defined in ISO 12312-1 for luminous transmittance and for blue light transmittance. To evaluate our prototype, we used a VARIAN Cary 5000 spectrophotometer, a gold standard in the field, to measure the luminous transmittance and the blue light transmittance of 60 sunglasses lenses. (and Bland-Altman analysis was performed) Bland-Altman analysis was performed and showed non-significant bias and narrow 95% limits of agreement within predefined tolerances for both luminous transmittance and blue light transmittance. The results show that the prototype is a viable means of providing blue light protection information to the general public and a quick and easy way for industry and retailers to test their products. In addition, our prototype plays an important role in educating the public about a feature to look for in sunglasses before purchasing.

Keywords: blue light, sunglasses, eye protective devices, transmittance measurement, standards, ISO 12312-1

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Authors: Chia-Yi Liu, Bo-Bin Xiao, Wen-Bin Lin, Hsiang-Ning Wu, Liang-Hsun Huang

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In order to reduce the risk of radiation damage that personnel may suffer during operations in the radiation environment, the use of automated guided vehicles to assist or replace on-site personnel in the radiation environment has become a key technology and has become an important trend. In this paper, we demonstrate our proof of concept for autonomous self-learning radiation source searcher in an unknown environment without a map. The research uses GPU version of Asynchronous Advantage Actor-Critic network (GA3C) of deep reinforcement learning to search for radiation sources. The searcher network, based on GA3C architecture, has self-directed learned and improved how search the anomalous radiation source by training 1 million episodes under three simulation environments. In each episode of training, the radiation source position, the radiation source intensity, starting position, are all set randomly in one simulation environment. The input for searcher network is the fused data from a 2D laser scanner and a RGB-D camera as well as the value of the radiation detector. The output actions are the linear and angular velocities. The searcher network is trained in a simulation environment to accelerate the learning process. The well-performance searcher network is deployed to the real unmanned vehicle, Dashgo E2, which mounts LIDAR of YDLIDAR G4, RGB-D camera of Intel D455, and radiation detector made by Institute of Nuclear Energy Research. In the field experiment, the unmanned vehicle is enable to search out the radiation source of the 18.5MBq Na-22 by itself and avoid obstacles simultaneously without human interference.

Keywords: deep reinforcement learning, GA3C, source searching, source detection

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Authors: Mohanad Hammad

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Port institutions serve as a link connecting the land areas that receive the goods and the areas from where ships sail. These areas hold great significance for the conversion of goods into commodities of economic value, capable of meeting the needs of the society. Development of ports constitutes a fundamental component of the comprehensive economic development process. Recognizing this fact, developing countries have always resorted to this infrastructural element to resolve the numerous problems they face, taking into account its contribution to the reformation of their economic conditions. Iraqi ports have played a major role in boosting the commercial movement in Iraq, as they are the starting point of its oil exports and a key constituent in fulfilling the consumer and production needs of the various economic sectors of Iraq. With the Gulf wars and the economic blockade, Iraqi ports have continued to deteriorate and become unable to perform their functions as first-generation ports, prompting Iraq to use the ports of neighboring countries such as Jordan's Aqaba commercial port. Meanwhile, Iraqi ports face strong competition from the ports of neighboring countries, which have achieved progress and advancement as opposed to the declining performance and efficiency of Iraqi ports. The great developments in the economic conditions of Iraq lay a too great burden on the Iraqi maritime transport and ports, which require development in order to be able to meet the challenges arising from the fierce international and regional competition in the markets. Therefore, it is necessary to find appropriate solutions in support of the role that can be played by Iraqi ports in serving Iraq's foreign trade transported by sea and in keeping up with the development of foreign trade. Thus, this research aims at tackling the current situation of the Iraqi ports and their commercial activity and studying the problems and obstacles they face. The research also studies the future prospects of these ports, the potentials of maritime openness to Iraq under the fierce competition of neighboring ports, and the possibility of enhancing Iraqi ports’ competitiveness. Among the results produced by this research is the future scenario it proposes for Iraqi ports, mainly represented in the establishment of Al-Faw Port, which will contribute to a greater openness of maritime transport in Iraq, and the rehabilitation and expansion of existing ports. This research seeks to develop solutions to Iraq ports so that they can be repositioned as a vital means of promoting economic development.

Keywords: maritime transport, port, future prospects, regional integration

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Authors: K. Paradkar, S. N. Mudliar, A. Sharma, A. B. Pandit, R. A. Pandey

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The study explores the hybrid combination of Hydrodynamic Cavitation (HC) and Subcritical Wet Air Oxidation-based pretreatment of complex industrial effluent to enhance the biodegradability selectively (without major COD destruction) to facilitate subsequent enhanced downstream processing via anaerobic or aerobic biological treatment. Advanced oxidation based techniques can be less efficient as standalone options and a hybrid approach by combining Hydrodynamic Cavitation (HC), and Wet Air Oxidation (WAO) can lead to a synergistic effect since both the options are based on common free radical mechanism. The HC can be used for initial turbulence and generation of hotspots which can begin the free radical attack and this agitating mixture then can be subjected to less intense WAO since initial heat (to raise the activation energy) can be taken care by HC alone. Lab-scale venturi-based hydrodynamic cavitation and wet air oxidation reactor with biomethanated distillery wastewater (BMDWW) as a model effluent was examined for establishing the proof-of-concept. The results indicated that for a desirable biodegradability index (BOD: COD - BI) enhancement (up to 0.4), the Cavitation (standalone) pretreatment condition was: 5 bar and 88 min reaction time with a COD reduction of 36 % and BI enhancement of up to 0.27 (initial BI - 0.17). The optimum WAO condition (standalone) was: 150oC, 6 bar and 30 minutes with 31% COD reduction and 0.33 BI. The hybrid pretreatment (combined Cavitation + WAO) worked out to be 23.18 min HC (at 5 bar) followed by 30 min WAO at 150oC, 6 bar, at which around 50% COD was retained yielding a BI of 0.55. FTIR & NMR analysis of pretreated effluent indicated dissociation and/or reorientation of complex organic compounds in untreated effluent to simpler organic compounds post-pretreatment.

Keywords: hybrid, hydrodynamic cavitation, wet air oxidation, biodegradability index

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Authors: Levent Taylan Ozgur Yildirim, Qihao Qian, John Yilin Wang

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A critical review of assessments of geological carbon dioxide (CO2) storage resources in Pennsylvania and the surrounding region was completed with a focus on the studies of Midwest Regional Carbon Sequestration Partnership (MRCSP), United States Department of Energy (US-DOE), and United States Geological Survey (USGS). Pennsylvania Geological Survey participated in the MRCSP Phase I research to characterize potential storage formations in Pennsylvania. The MRCSP’s volumetric method estimated ~89 gigatonnes (Gt) of total CO2 storage resources in deep saline formations, depleted oil and gas reservoirs, coals, and shales in Pennsylvania. Meanwhile, the US-DOE calculated storage efficiency factors using log-odds normal distribution and Monte Carlo sampling, revealing contingent storage resources of ~18 Gt to ~20 Gt in deep saline formations, depleted oil and gas reservoirs, and coals in Pennsylvania. Additionally, the USGS employed Beta-PERT distribution and Monte Carlo sampling to determine buoyant and residual storage efficiency factors, resulting in 20 Gt of contingent storage resources across four storage assessment units in Appalachian Basin. However, few studies have explored CO2 storage resources in shales in the region, yielding inconclusive findings. This article provides a critical and most up to date review and analysis of geological CO2 storage resources in Pennsylvania and the region.

Keywords: carbon capture and storage, geological CO2 storage, pennsylvania, appalachian basin

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Authors: S. Albert, R. Cossu, A. Grinham, C. Heatherington, C. Wilson

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Shipping trends suggest increasing vessel size and draught visiting Australian ports highlighting potential challenges to port infrastructure and requiring optimization of shipping channels to ensure safe passage for vessels. The Port of Brisbane in Queensland, Australia has an 80 km long access shipping channel which vessels must transit 15 km of relatively shallow coffee rock (generic class of indurated sands where sand grains are bound within an organic clay matrix) outcrops towards the northern passage in Moreton Bay. This represents a risk to shipping channel deepening and maintenance programs as the dredgeability of this material is more challenging due to its high cohesive strength compared with the surrounding marine sands and potential higher acid sulfate risk. In situ assessment of acid sulfate sediment for dredge spoil control is an important tool in mitigating ecological harm. The coffee rock in an anoxic undisturbed state does not pose any acid sulfate risk, however when disturbed via dredging it’s vital to ensure that any present iron sulfides are either insignificant or neutralized. To better understand the potential risk we examined the reduction potential of coffee rock across the entire dredge cycle in order to accurately portray the true outcome of disturbed acid sulfate sediment in dredging operations in Moreton Bay. In December 2014 a dredge trial was undertaken with a trailing suction hopper dredger. In situ samples were collected prior to dredging revealed acid sulfate potential above threshold guidelines which could lead to expensive dredge spoil management. However, potential acid sulfate risk was then monitored in the hopper and subsequent discharge, both showing a significant reduction in acid sulfate potential had occurred. Additionally, the acid neutralizing capacity significantly increased due to the inclusion of shell fragments (calcium carbonate) from the dredge target areas. This clearly demonstrates the importance of assessing potential acid sulfate risk across the entire dredging cycle and highlights the need to carefully evaluate sources of acidity.

Keywords: acid sulfate, coffee rock, indurated sand, dredging, maintenance dredging

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Authors: Muhammad Bilal, Zhongfeng Qiu

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Aerosols, suspended particles in the atmosphere, play an important role in the earth energy budget, climate change, degradation of atmospheric visibility, urban air quality, and human health. To fully understand aerosol effects, retrieval of aerosol optical properties such as aerosol optical depth (AOD) at high spatiotemporal resolution is required. Therefore, in the present study, hourly AOD observations at 500 m resolution were retrieved from the geostationary ocean color imager (GOCI) using the simplified aerosol retrieval algorithm (SARA) over the urban area of Beijing for the year 2016. The SARA requires top-of-the-atmosphere (TOA) reflectance, solar and sensor geometry information and surface reflectance observations to retrieve an accurate AOD. For validation of the GOCI retrieved AOD, AOD measurements were obtained from the aerosol robotic network (AERONET) version 3 level 2.0 (cloud-screened and quality assured) data. The errors and uncertainties were reported using the root mean square error (RMSE), relative percent mean error (RPME), and the expected error (EE = ± (0.05 + 0.15AOD). Results showed that the high spatiotemporal GOCI AOD observations were well correlated with the AERONET AOD measurements with a correlation coefficient (R) of 0.92, RMSE of 0.07, and RPME of 5%, and 90% of the observations were within the EE. The results suggested that the SARA is robust and has the ability to retrieve high-resolution spatiotemporal AOD observations over the urban area using the geostationary satellite.

Keywords: AEORNET, AOD, SARA, GOCI, Beijing

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Authors: Sharon Milberger, Jane Turner, Denise White-Perkins

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Michigan shares the overall U.S. national need for more highly qualified professionals who have knowledge and experience in the use of evidence-based practices to meet the special health care needs of children, adolescents, and adults with neurodevelopmental disabilities including autism spectrum disorder (DD/ASD). The Michigan Leadership Education in Neurodevelopmental Disabilities (MI-LEND) program is a consortium of six universities that spans the state of Michigan and serves more than 181,800 undergraduate, graduate, and professional students. The purpose of the MI LEND program is to improve the health of infants, children and adolescents with disabilities in Michigan by training individuals from different disciplines to assume leadership roles in their respective fields and work across disciplines. The MI-LEND program integrates “L.I.F.E.” perspectives into all training components. L.I.F.E. is an acronym for Leadership, Interdisciplinary, Family-Centered and Equity perspectives. This paper will describe how L.I.F.E. perspectives are embedded into all aspects of the MI-LEND training program including the application process, didactic training, community and clinical experiences, discussions, journaling and projects. Specific curriculum components will be described including content from a training module dedicated to Equity. Upon completion of the Equity module, trainees are expected to be able to: 1) Use a population health framework to identify key social determinants impacting families and children; 2) Explain how addressing bias and providing culturally appropriate linguistic care/services can influence patient/client health and wellbeing; and 3) Describe the impact of policy and structural/institutional factors influencing care and services for children with DD/ASD and their families. Each trainee completes two self-assessments: the Cultural and Linguistic Competence Health Practitioner Assessment and the other assessing social attitudes/implicit bias. Trainees also conduct interviews with a family with a child with DD/ASD. In addition, interdisciplinary Equity-related group activities are incorporated into face-to-face training sessions. Each MI-LEND trainee has multiple ongoing opportunities for self-reflection through discussion and journaling and completion of a L.I.F.E. project as a culminating component of the program. The poster will also discuss the challenges related to teaching and measuring successful outcomes related to diversity/equity perspectives.

Keywords: disability, diversity, equity, training

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Authors: Leandra Prempeh, Emily Malugen

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Prenatal drug exposure can have a molecular impact on the hypothalamic and reward genes that regulate feeding behavior. This can impact feeding regulation, resulting in feeding difficulties and growth failure. This was potentially seen in “McKayla,” a 19- month old girl with a history of in-utero drug exposure, patent ductus arteriosus, and gastroesophageal reflux disease who presented for intensive day treatment feeding therapy. She was diagnosed with Avoidant Restrictive Food Intake Disorder, described as total food refusal and meeting 100% of her caloric needs from a gastrostomy tube. The primary goals during intensive feeding therapy were to increase her oral intake and decrease her reliance on supplementation with formula. Several behavioral antecedent manipulations were implemented to establish consistent responding and make progress towards treatment goals. This included multiple modified bolus placements (using underloaded and Nuk brush), reinforcement contingencies, and variety fading before stability was finally achieved. Following, increasing retention of bites then increasing volume and variety were goals targeted. From treatment onset to the last 3 days of treatment, McKayla's rate of rapid acceptance of bite presentations increased significantly from 33.33% to 93.13%, rapid swallowing went from 0.00% to 92.32%, and her percentage of inappropriate mealtime behavior and expels decreased from 58.33% and 100% to 2.31% and 7.68%, respectively. Overall, the treatment team successfully introduced and increased the bite size of 7 pureed foods, generalize the treatment to caregivers with high integrity, and began facilitating tube weaning. She was receiving about 33.42% of her needs by mouth at the time of discharge. Other nutritional concerns addressed during treatment included drinking a nutritionally complete drink out of an open cup and age appropriate growth. McKayla continued to have emesis almost daily, as was her baseline before starting treatment; however, the frequency during mealtime decreased. Overall, McKayla responded well to treatment. She had a very slow response to treatment and required a lot of antecedent manipulations to establish consistent responding. As the literature suggests, [drug]-exposed neonates, like McKayla, may be at increased risk for nutritional and growth challenges that may persist throughout development. This supports the need for longterm follow-up of infant growth.

Keywords: behavioral intervention, feeding problems, in-utero drug exposure, intensive multidisciplinary intervention

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Authors: Zeeshan Ahmed, Ajinkya Sarode, Pratik Basarkar, Atul Bhargav, Debjyoti Banerjee

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The use of CO₂ in oil recovery and in CO₂ capture and storage is gaining traction in recent years. These applications involve heat transfer between CO₂ and the base fluid, and hence, there arises a need to improve the thermal conductivity of CO₂ to increase the process efficiency and reduce cost. One way to improve the thermal conductivity is through nanoparticle addition in the base fluid. The nanofluid model in this study consisted of copper (Cu) nanoparticles in varying concentrations with CO₂ as a base fluid. No experimental data are available on thermal conductivity of CO₂ based nanofluid. Molecular dynamics (MD) simulations are an increasingly adopted tool to perform preliminary assessments of nanoparticle (NP) fluid interactions. In this study, the effect of the formation of a nanolayer (or molecular layering) at the gas-solid interface on thermal conductivity is investigated using equilibrium MD simulations by varying NP diameter and keeping the volume fraction (1.413%) of nanofluid constant to check the diameter effect of NP on the nanolayer and thermal conductivity. A dense semi-solid fluid layer was seen to be formed at the NP-gas interface, and the thickness increases with increase in particle diameter, which also moves with the NP Brownian motion. Density distribution has been done to see the effect of nanolayer, and its thickness around the NP. These findings are extremely beneficial, especially to industries employed in oil recovery as increased thermal conductivity of CO₂ will lead to enhanced oil recovery and thermal energy storage.

Keywords: copper-CO2 nanofluid, molecular dynamics simulation, molecular interfacial layer, thermal conductivity

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Authors: H. R. Vosoughifar, Seyedeh Zeinab. Hosseininejad, Nahid Shabazi, Seyed Mohialdin Hosseininejad

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In recent years, structure designers advocate further application of energy absorption devices for lateral loads damping. The Un-bonded Braced Frame (UBF) system is one of the efficient damping systems, which is made of a smart combination of steel and concrete or mortar. In this system, steel bears the earthquake-induced axial force as compressive or tension forces without loss of strength. Concrete or mortar around the steel core acts as a constraint for brace and prevents brace buckling during seismic axial load. In this study, the optimal bracing system in the high-rise structures has been evaluated considering the seismic stress distribution in the connections. An actual 18-story structure was modeled using the proper Finite Element (FE) software where braced with UBF, Eccentrically Braced Frames (EBF) and Concentrically Braced Frame (CBF) systems. Nonlinear static pushover and time-history analyses are then performed so that the acquired results demonstrate that the UBF system reduces drift values in the high-rise buildings. Further statistical analyses show that there is a significant difference between the drift values of UBF system compared with those resulted from the EBF and CBF systems. Hence, the seismic stress distribution in the connections of the proposed structure which braced with UBF system was investigated.

Keywords: optimal bracing system, high-rise structure, finite element analysis (FEA), seismic stress

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Authors: Hashem Shariatmadar, Mozhgansadat Momtazdargahi

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The purpose of control structure against earthquake is to dissipate earthquake input energy to the structure and reduce the plastic deformation of structural members. There are different methods for control structure against earthquake to reduce the structure response that they are active, semi-active, inactive and hybrid. In this paper two different combined control systems are used first system comprises base isolator and multi tuned mass dampers (BI & MTMD) and another combination is hybrid base isolator and multi tuned mass dampers (HBI & MTMD) for controlling an eight story isolated benchmark steel structure. Active control force of hybrid isolator is estimated by fuzzy logic algorithms. The influences of the combined systems on the responses of the benchmark structure under the two near-field earthquake (Newhall & Elcentro) are evaluated by nonlinear dynamic time history analysis. Applications of combined control systems consisting of passive or active systems installed in parallel to base-isolation bearings have the capability of reducing response quantities of base-isolated (relative and absolute displacement) structures significantly. Therefore in design and control of irregular isolated structures using the proposed control systems, structural demands (relative and absolute displacement and etc.) in each direction must be considered separately.

Keywords: base-isolated benchmark structure, multi-tuned mass dampers, hybrid isolators, near-field earthquake, fuzzy algorithm

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Authors: Cheng-Chi Yu, Chi-Shiun Chiou

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This study developed a plug-in hybrid powertrain system which consisted of two continuous variable transmissions. By matching between the engine, motor, generator, and dual continuous variable transmissions, this integrated power system can take advantages of the components. The hybrid vehicle can be driven by the internal combustion engine, or electric motor alone, or by these two power sources together when the vehicle is driven in hard acceleration or high load. The energy management of this integrated hybrid system controls the power systems based on rule-based control strategy to achieve better fuel economy. When the vehicle driving power demand is low, the internal combustion engine is operating in the low efficiency region, so the internal combustion engine is shut down, and the vehicle is driven by motor only. When the vehicle driving power demand is high, internal combustion engine would operate in the high efficiency region; then the vehicle could be driven by internal combustion engine. This strategy would operate internal combustion engine only in optimal efficiency region to improve the fuel economy. In this research, the vehicle simulation model was built in MATLAB/ Simulink environment. The analysis results showed that the power coupled efficiency of the hybrid powertrain system with dual continuous variable transmissions was better than that of the Honda hybrid system on the market.

Keywords: plug-in hybrid power system, fuel economy, performance, continuously variable transmission

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Authors: Yi-Chun Wu, Nai-Yun Chang, Chuan LI

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This study investigates a feasible range of composition for the mixture of gelatin and polyvinyl alcohol to form nanofibers by electrospinning. Gelatin, one of the most available naturally derived hydrogels of amino acids, is a popular choice for food additives, cosmetic ingredients, biomedical implants, or dressing of its non-toxic and biodegradable nature. Nevertheless, synthetic hydrogel polyvinyl alcohol has long been used as a thickening agent for adhesion purposes. Many biomedical devices are also containing polyvinyl-alcohol as a major content, such as eye drops and contact lenses. To discover appropriate compositions of gelatin and polyvinyl-alcohol for electrospun nanofibers, polymer solutions of different volumetric ratios between gelatin and polyvinyl alcohol were prepared for electrospinning. The viscosity, surface tension, pH value, and electrical conductance of polymer solutions were measured. On the nanofibers, the vibrational modes of molecular structures in nanofibers were investigated by Fourier-transform infrared spectroscopy. The morphologies and surface chemical elements of fibers were examined by the scanning electron microscope and the energy-dispersive X-ray spectroscopy. The hydrophilicity of nanofiberswas evaluated by the water contact angles on the surface of the fibers. To further test the biotoxicity of nanofibers, an in-vitro 3T3 fibroblasts culture further tested the biotoxicity of the electrospun nanofibers. Throughstatistical analyses of the experimental data, it is found that the polyvinyl-alcohol rich composition (the volumetric ratio of gelatin/polyvinyl-alcohol < 1) would be a preferable choice for the formation of nanofibers by the current setup of electrospinning. These electrospun nanofibers tend to be hydrophilic with no biotoxicity threat to the 3T3 fibroblasts.

Keywords: gelatin, polyvinyl-alcohol, nanofibers, electrospinning, spin coating

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Authors: Lihyo Sung

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Background: Children and teens in Korea experience extreme levels of academic stress. To perform better on the college entrance exam and gain admission to Korea’s most prestigious universities, they devote a significant portion of their early lives to studying. Because of their excessive preparation for entrance exams, students have become accustomed to passive and involuntary engagement. Any student starting university, however, faces new challenges that require more active involvement and self-regulated practice. As a way to tackle this issue, the study focuses on investigating the mediating effects of positive psychological capital on the relationship between self-leadership and career maturity among Korean university students. Objectives and Hypotheses: The long term goal of this study is to offer insights that promote the use of positive psychological interventions in the development and adaptation of career maturity. The current objective is to assess the role of positive psychological capital as a mediator between self-leadership and career maturity among Korean university students. Based on previous research, the hypotheses are: (a) self-leadership will be positively associated with indices of career maturity, and (b) positive psychological capital will partially or fully mediate the relationship between self-leadership and career maturity. Sample Characteristics and Sample Size: Participants in the current study consisted of undergraduate students enrolled in various courses at 5 large universities in Korea. A total of 181 students participated in the study. Methodology: A quantitative research design was adopted to test the hypotheses proposed in the current study. By using a cross-sectional approach to research, a self-administered questionnaire was used to collect data on indices of positive psychological capital, self-leadership, and career maturity. The data were analyzed by means of Cronbach's alpha, Pierson correlation test, multiple regression, path analysis, and SPSS for Windows version 22.0 using descriptive statistics. Results: Findings showed that positive psychological capital fully mediated the relationship between self-leadership and career maturity. Self-leadership significantly impacted positive psychological capital and career maturity, respectively. Scientific Contribution: The results of the current study provided useful insights into the role of psychological strengths such as positive psychological capital in improving self-leadership and career maturity. Institutions can assist in increasing positive psychological capital through the creation of positive experiences for undergraduate students, such as opportunities for coaching and mentoring.

Keywords: career maturity, mediating role, positive psychological capital, self-leadership

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Authors: Ahmad Nawid Mirzad, Akira Goto, Takuto Endo, Hitoshi Ano, Hiromu Katamoto, Takenori Yamauchi

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The objective of this study was to evaluate the effects of live yeast supplementation on oxidative stress biomarker and antioxidant vitamin levels as well as lactation performance in Holstein Friesian cows during the summer season in Fukuoka prefecture. Sixteen lactating cows weighing 707.50 ± 13.09 kg (Mean ± SE) were used and randomly assigned to either supplemented (n = 8) or control (n = 8) group. The cows in supplemented group were administered with live yeast product at 10 g/d per cow from middle of July to middle of September for eight weeks. In treatment group, serum levels of derivatives of reactive oxygen metabolites (d-ROMs) were lower at week six. In addition, serum levels of glucose and retinol were higher at week eight and those of α-tocopherol were higher at week 2 in treatment group. During study period daily average milk yield decreased in both groups. Daily average milk yield 63 days after the onset of supplementation in treatment and control groups were 23.5 and 22.2 kg, respectively. The reduction rate of milk yield in treatment group tended to be lower (17.6 vs. 20.0%). These results suggest that live yeast supplementation may reduce oxidative stress and improve energy metabolism in lactating dairy cows during the summer season.

Keywords: cow, live yeast, milk, oxidative stress, summer season

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Authors: Rejane Maria P. da Silva, Mariana X. Milagre, João Victor de S. Araujo, Leandro A. de Oliveira, Renato A. Antunes, Isolda Costa

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The Al-Cu-Li alloys are advanced materials for aerospace application because of their interesting mechanical properties and low density when compared with conventional Al-alloys. However, Al-Cu-Li alloys are susceptible to localized corrosion. The near-surface deformed layer (NSDL) induced by the rolling process during the production of the alloy and its removal by polishing can influence on the corrosion susceptibility of these alloys. In this work, the influence of surface preparation effects on the electrochemical activity of AA2098-T351 (Al–Cu–Li alloy) was investigated using a correlation between surface chemistry, microstructure, and electrochemical activity. Two conditions were investigated, polished and as-received surfaces of the alloy. The morphology of the two types of surfaces was investigated using confocal laser scanning microscopy (CLSM) and optical microscopy. The surface chemistry was analyzed by X-ray Photoelectron Spectroscopy (XPS) and energy dispersive X-ray spectroscopy (EDS). Global electrochemical techniques (potentiodynamic polarization and EIS technique) and a local electrochemical technique (Localized Electrochemical Impedance Spectroscopy-LEIS) were used to examine the electrochemical activity of the surfaces. The results obtained in this study showed that in the as-received surface, the near-surface deformed layer (NSDL), which is composed of Mg-rich bands, influenced the electrochemical behavior of the alloy. The results showed higher electrochemical activity to the polished surface condition compared to the as-received one.

Keywords: Al-Cu-Li alloys, surface preparation effects, electrochemical techniques, localized corrosion

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Authors: Alan Collins

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This study explains how The People’s Tribunal empowered survivors of child abuse. It examines how People’s tribunals can be effective mean of empowerment; the challenges of empowerment – expectation v. reality; the findings and how they reflect other inquiry findings; and the importance of listening and learning from survivors. UKCSAPT “The People’s Tribunal” was established by survivors of child sex abuse and members of civil society to investigate historic cases of institutional sex abuse. The independent inquiry, led by a panel of four judges, listened to evidence spanning four decades from survivors and experts. A common theme throughout these accounts showed that a series of institutional failures prevented abuse from being reported; and that there are clear links between children being rendered vulnerable by these failures and predatory abuse on an organised scale. It made a series of recommendations including the establishment of a permanent and open forum for victims to share experiences and give evidence, better links between mental health services and police investigations, and training for police and judiciary professionals on the effects of undisclosed sexual abuse. The main findings of the UKCSAPT report were:-There are clear links between children rendered vulnerable by institutional failures and predatory abuse on an organised scale, even if these links often remain obscure. -UK governmental institutions have failed to provide survivors with meaningful opportunities for either healing or justice. -The vital mental health needs of survivors are not being met and this undermines both their psychological recovery and access to justice. -Police and other authorities often lack the training to understand the complex reasons for the inability of survivors to immediately disclose a history of abuse. -Without far-reaching changes in institutional culture and practices, the sexual abuse of children will continue to be a significant scourge in the UK. The report also outlined a series of recommendations for improving reporting and mental health provision, and access to justice for victims were made, including: -A permanent, government-funded popular tribunal should be established to enable survivors to come forward and tell their stories. -Survivors giving evidence should be assigned an advocate to assist their access to justice. -Mental health services should be linked to police investigations to help victims disclose abuse. -Victims who fear reprisals should be provided with a channel though which to give evidence anonymously.

Keywords: empowerment, survivors, sexual, abuse

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Authors: Mark De Ste Croix, Jonathan Hughes, Francisco Ayala, Michal Lehnert

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There are well-known challenges to implementing injury prevention training for youth players but no data are available on the knowledge and understanding of deliverers of such programmes at grass root level. To increase adoption and adherence to such programmes coach knowledge and understanding of injury risk and prevention is essential. Therefore, the purpose of this study was to examine grass-root coaches knowledge and understanding of injury risk and prevention in youth players. 68 grass root coaches (18 females and 50 males) who were attending a one-day injury prevention workshop completed a modified validated questionnaire exploring knowledge and understanding of injury risk and prevention in youth players. Only 59% of coaches agreed that youth players are at a high risk of suffering an injury. There were high levels of agreement that injuries can have negative impacts on team performance (75%) and can cause physical problems in later life (85%), however only around half of coaches felt that injuries affect youth players current quality of life (59%). There was strong agreement that it is possible to prevent injuries in youth players (84%), but coaches were generally unaware of programs to help prevent injuries (84%), and only 9% used some form of injury prevention program. Despite this, nearly all coaches felt that their coaching could benefit from a greater understanding of growth and maturation (91%), injury prevention programmes (91%) and specific exercises (93%) for youth athletes. 17% of coaches rated their knowledge of injury prevention as good/very good at the start of the workshop and this increased to 94% at the end of the workshop. 62% of coaches identified their attitude towards injury prevention as indifferent at the start of the workshop compared with only 1% at the end. Only 14% of coaches at the start of the workshop were confident to deliver an injury prevention session but 83% stated they were confident by the end of the workshop. Finally, 98% of coaches felt that the workshop provided them with the confidence and the knowledge to deliver an injury prevention session and 98% suggested that they would implement injury prevention into their coaching. These data suggest that there is a lack of understanding of grass root coaches that children are a high-risk group for injuries, and that such injuries impact on current quality of life. Despite understanding that injuries can be prevented most grass root coaches do not have the knowledge to implement injury prevention into their coaching and very few do. There is a common consensus amongst these coaches that a greater understanding of such programmes will enhance their coaching. The injury prevention workshop appears to have increased the knowledge and changed the attitude of coaches towards injury prevention. All coaches felt that the workshop provided them with the tools to adopt, implement and deliver injury prevention in their coaching. These data highlight that there is a clear need for education regarding injury risk and prevention to be embedded within the coach education pathway, especially at grass root level.

Keywords: coach education, injury prevention, knowledge, and understanding, youth

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Authors: Farzad Jafarpour Taher, Maghsud Solimanpur

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Production planning is one of the complex tasks in multi-product firms that produce a wide range of products. Since resources in mass production companies are limited and different products use common resources, there must be a careful plan so that firms can respond to customer needs efficiently. Azar-battery Company is a firm that provides twenty types of products for its customers. Therefore, careful planning must be performed in this company. In this research, the current conditions of Azar-battery Company were investigated to provide a mathematical programming model to determine the optimum production rate of the products in this company. The production system of this company is multi-stage, multi-product and multi-period. This system is studied in terms of a one-year planning horizon regarding the capacity of machines and warehouse space limitation. The problem has been modeled as a linear programming model with deterministic demand in which shortage is not allowed. The objective function of this model is to minimize costs (including raw materials, assembly stage, energy costs, packaging, and holding). Finally, this model has been solved by Lingo software using the branch and bound approach. Since the computation time was very long, the solver interrupted, and the obtained feasible solution was used for comparison. The proposed model's solution costs have been compared to the company’s real data. This non-optimal solution reduces the total production costs of the company by about %35.

Keywords: multi-period, multi-product production, multi-stage, production planning

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Authors: Saurabh Gupta, Vanshdeep Parmar, Sri Harsha Reddy Yelly, Michele Baker, Elizabeth Bigler, Kunhee Choi

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It is known that the adoption of solar powered LED highway lighting systems or sensory LED highway lighting systems can dramatically reduce energy consumption by 55 percent when compared to conventional on-grid High Pressure Sodium (HPS) lamps that are widely applied to most highways. However, an initial high installation cost for building the infrastructure of solar photovoltaic devices hampers a wider adoption of such technologies. This research aims to examine currently available state-of-the-art solar photovoltaic and sensory technologies, identify major obstacles, and analyze each technology to create a benchmarking metrics from the benefit-cost analysis perspective. The on-grid HPS lighting systems will serve as the baseline for this study to compare it with other lighting alternatives such as solar and sensory LED lighting systems. This research will test the validity of the research hypothesis that alternative LED lighting systems produce more favorable benefit-cost ratios and the added initial investment costs are recouped by the savings in the operation and maintenance cost. The payback period of the excess investment and projected savings over the life-cycle of the selected lighting systems will be analyzed by utilizing the concept of Net Present Value (NPV). Researchers believe that if this study validates the research hypothesis, it can promote a wider adoption of alternative lighting systems that will eventually save millions of taxpayer dollars in the long-run.

Keywords: lighting systems, sensory and solar PV, benefit cost analysis, net present value

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Authors: Saurabh Satija, Munish Garg

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Present work reports an efficient extraction method using microwaves based solvent–sample duo-heating mechanism, for the extraction of an important anti-diabetic plant Tinospora cordifolia from AYUSH system for estimation of berberine content. The process is based on simultaneous heating of sample matrix and extracting solvent under microwave energy. Methanol was used as the extracting solvent, which has excellent berberine solubilizing power and warms up under microwave attributable to its great dispersal factor. Extraction conditions like time of irradition, microwave power, solute-solvent ratio and temperature were optimized using Taguchi design and berberine was quantified using high performance thin layer chromatography. The ranked optimized parameters were microwave power (rank 1), irradiation time (rank 2) and temperature (rank 3). This kind of extraction mechanism under dual heating provided choice of extraction parameters for better precision and higher yield with significant reduction in extraction time under optimum extraction conditions. This developed extraction protocol will lead to extract higher amounts of berberine which is a major anti-diabetic moiety in Tinospora cordifolia which can lead to development of cheaper formulations of the plant Tinospora cordifolia and can help in rapid prevention of diabetes in the world.

Keywords: berberine, microwave, optimization, Taguchi

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Authors: Dejen Alemu, Murray E. Jennex, Temtim Assefa

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This paper is investigated to understand the design, the use, and the consequence of Knowledge Management System (KMS) for knowledge systems sharing and integration. A KMS for knowledge systems sharing and integration is designed to meet the challenges raised by knowledge management researchers and practitioners: the technical, the human, and social factors. Agricultural KMS involves various members coming from different Communities of Practice (CoPs) who possess their own knowledge of multiple practices which need to be combined in the system development. However, the current development of the technology ignored the indigenous knowledge of the local communities, which is the key success factor for agriculture. This research employed the multi-methodological approach to KMS research in action research perspective which consists of four strategies: theory building, experimentation, observation, and system development. Using the KMS development practice of Ethiopian agricultural transformation agency as a case study, this research employed an interpretive analysis using primary qualitative data acquired through in-depth semi-structured interviews and participant observations. The Orlikowski's structuration model of technology has been used to understand the design, the use, and the consequence of the KMS. As a result, the research identified three basic components for the architecture of the shared KMS, namely, the people, the resources, and the implementation subsystems. The KMS were developed using web 2.0 tools to promote knowledge sharing and integration among diverse groups of users in a distributed environment. The use of a shared KMS allows users to access diverse knowledge from a number of users in different groups of participants, enhances the exchange of different forms of knowledge and experience, and creates high interaction and collaboration among participants. The consequences of a shared KMS on the social system includes, the elimination of hierarchical structure, enhance participation, collaboration, and negotiation among users from different CoPs having common interest, knowledge and skill development, integration of diverse knowledge resources, and the requirement of policy and guideline. The research contributes methodologically for the application of system development action research for understanding a conceptual framework for KMS development and use. The research have also theoretical contribution in extending structuration model of technology for the incorporation of variety of knowledge and practical implications to provide management understanding in developing strategies for the potential of web 2.0 tools for sharing and integration of indigenous knowledge.

Keywords: communities of practice, indigenous knowledge, participation, structuration model of technology, Web 2.0 tools

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Authors: A. A. Dare, E. U. Iniegbedion

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Industrial furnaces generally involve enclosures of fire typically initiated by the combustion of gases. The fire leads to temperature distribution inside the enclosure. A proper understanding of the temperature and velocity distribution within the enclosure is often required for optimal design and use of the furnace. This study was therefore directed at numerical modeling of temperature distribution inside an enclosure as typical in a furnace. A mathematical model was developed from the conservation of mass, momentum and energy. The stream function-vorticity formulation of the governing equations was solved by an alternating direction implicit (ADI) finite difference technique. The finite difference formulation obtained were then developed into a computer code. This was used to determine the temperature, velocities, stream function and vorticity. The effect of the wall heat conduction was also considered, by assuming a one-dimensional heat flow through the wall. The computer code (MATLAB program) developed was used for the determination of the aforementioned variables. The results obtained showed that the transient temperature distribution assumed a uniform profile which becomes more chaotic with increasing time. The vertical velocity showed increasing turbulent behavior with time, while the horizontal velocity assumed decreasing laminar behavior with time. All of these behaviours were equally reported in the literature. The developed model has provided understanding of heat transfer process in an industrial furnace.

Keywords: heat source, modelling, enclosure, furnace

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Authors: Padmalochan Panda, R. Ramaseshan

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Aluminum nitride (AlN) is a potential candidate for semiconductor industry due to its wide band gap (6.2 eV), high thermal conductivity and low thermal coefficient of expansion. A-plane oriented AlN film finds an important role in deep UV-LED with higher isotropic light extraction efficiency. Also, Cr-doped AlN films exhibit dilute magnetic semiconductor property with high Curie temperature (300 K), and thus compatible with modern day microelectronics. In this work, highly a-axis oriented wurtzite AlN and Al1-xMxN (M = Cr, Ti) films have synthesized by reactive co-sputtering technique at different concentration. Crystal structure of these films is studied by Grazing incidence X-ray diffraction (GIXRD) and Transmission electron microscopy (TEM). Identification of binding energy and concentration (x) in these films is carried out by X-ray photoelectron spectroscopy (XPS). Local crystal structure around the Cr and Ti atom of these films are investigated by X-ray absorption spectroscopy (XAS). It is found that Cr and Ti replace the Al atom in AlN lattice and the bond lengths in first and second coordination sphere with N and Al, respectively, decrease concerning doping concentration due to strong p-d hybridization. The nano-indentation hardness of Cr and Ti-doped AlN films seems to increase from 17.5 GPa (AlN) to around 23 and 27.5 GPa, respectively. An-isotropic optical properties of these films are studied by the Spectroscopic Ellipsometry technique. Refractive index and extinction coefficient of these films are enhanced in normal dispersion region as compared to the parent AlN film. The optical band gap energies also seem to vary between deep UV to UV regions with the addition of Cr, thus by bringing out the usefulness of these films in the area of optoelectronic device applications.

Keywords: ellipsometry, GIXRD, hardness, XAS

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Authors: Sara Mercedes Barroso Pinzón, Antonio Javier Sanchéz Herencia, Begoña Ferrari, Álvaro Jesús Castro

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The current need for durable implants and bone substitutes characterised by biocompatibility, bioactivity and mechanical properties, without immunological rejection, is a major challenge for scientists. Hydroxyapatite (HAp) has been considered for decades as an ideal biomaterial for bone regeneration due to its chemical and crystallographic similarity to the mineral structure bioapatites. However, the lack of trace elements in the hydroxyapatite structure gives it very low mechanical and biological properties. In this sense, the objective of the research is to address the synthesis of hydroxyapatite with Mg from phosphate rock from sedimentary deposits in the central-eastern region of Colombia, taking advantage of the release of the species contained as natural precursors of Ca, P and Mg. The minerals present were studied, fluorapatite as the mineral of interest associated with mineralogical species of magnesium carbonates and quartz. The chemical and mineralogical composition was determined by X-ray fluorescence (XRF) and X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX); as well as the evaluation of the surface physicochemical properties of zeta potential (PZC), with the aim of studying the surface behaviour of the microconstituents present in the phosphate rock and to elucidate the synergistic mechanism between the minerals and establish the optimum conditions for the wet concentration process. From the products obtained and characterised by XRD, XRF, SEM, FTIR, RAMAN, HAp-Mg biocomposite scaffolds are fabricated and the influence of Mg on the morphometric parameters, mechanical and biological properties of the designed materials is evaluated.

Keywords: phosphate rock, hydroxyapatite, magnesium, biomaterials

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Authors: José M. Liñeira Del Río, Ramón Rial, Khodor Nasser, María J.G. Guimarey

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The need to develop new lubricants that offer better anti-friction and anti-wear performance in internal combustion vehicles is one of the great challenges of lubrication in the automotive field. The addition of nanoparticles has emerged as a possible solution and, combined with the lubricating power of ionic liquids, may become one of the alternatives to reduce friction losses and wear of the contact surfaces in the conditions to which tribo-pairs are subjected, especially in the contact of the piston rings and the cylinder liner surface. In this study, the improvement in SAE 10W-40 engine oil tribological performance after the addition of magnesium oxide (MgO) nanoadditives and two different phosphonium-based ionic liquids (ILs) was investigated. The nanoparticle characterization was performed by means of transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM). The tribological properties, friction coefficients and wear parameters of the formulated oil modified with 0.01 wt.% MgO and 1 wt.% ILs compared with the neat 10W-40 oil were performed and analyzed using a ball-on-three-pins tribometer and a 3D optical profilometer, respectively. Further analysis on the worn surface was carried out by Raman spectroscopy and SEM microscopy, illustrating the formation of the protective IL and MgO tribo-films as hybrid additives. In friction tests with sliding steel-steel tribo-pairs, IL3-based hybrid nanolubricant decreased the friction coefficient and wear volume by 7% and 59%, respectively, in comparison with the neat SAE 10W-40, while the one based on IL1 only achieved a reduction of these parameters by 6% and 39%, respectively. Thus, the tribological characterization also revealed that the MgO and IL3 addition has a positive synergy over the commercial lubricant, adequately meeting the requirements for their use in internal combustion engines. In summary, this study has shown that the addition of ionic liquids to MgO nanoparticles can improve the stability and lubrication behavior of MgO nanolubricant and encourages more investigations on using nanoparticle additives with green solvents such as ionic liquids to protect the environment as well as prolong the lifetime of machinery. The improvement in the lubricant properties was attributed to the following wear mechanisms: the formation of a protective tribo-film and the ability of nanoparticles to fill out valleys between asperities, thereby effectively smoothing out the shearing surfaces.

Keywords: lubricant, nanoparticles, phosphonium-based ionic liquids, tribology

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Authors: Hoa Pham

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The literature on language teaching and second language acquisition has been largely driven by monolingual ideology with a common assumption that a second language (L2) is best taught and learned in the L2 only. The current study challenges this assumption by reporting learners' positive perceptions of tertiary level teachers' code switching practices in Vietnam. The findings of this study contribute to our understanding of code switching practices in language classrooms from a learners' perspective. Data were collected from student participants who were working towards a Bachelor degree in English within the English for Business Communication stream through the use of focus group interviews. The literature has documented that this method of interviewing has a number of distinct advantages over individual student interviews. For instance, group interactions generated by focus groups create a more natural environment than that of an individual interview because they include a range of communicative processes in which each individual may influence or be influenced by others - as they are in their real life. The process of interaction provides the opportunity to obtain the meanings and answers to a problem that are "socially constructed rather than individually created" leading to the capture of real-life data. The distinct feature of group interaction offered by this technique makes it a powerful means of obtaining deeper and richer data than those from individual interviews. The data generated through this study were analysed using a constant comparative approach. Overall, the students expressed positive views of this practice indicating that it is a useful teaching strategy. Teacher code switching was seen as a learning resource and a source supporting language output. This practice was perceived to promote student comprehension and to aid the learning of content and target language knowledge. This practice was also believed to scaffold the students' language production in different contexts. However, the students indicated their preference for teacher code switching to be constrained, as extensive use was believed to negatively impact on their L2 learning and trigger cognitive reliance on the L1 for L2 learning. The students also perceived that when the L1 was used to a great extent, their ability to develop as autonomous learners was negatively impacted. This study found that teacher code switching was supported in certain contexts by learners, thus suggesting that there is a need for the widespread assumption about the monolingual teaching approach to be re-considered.

Keywords: codeswitching, L1 use, L2 teaching, learners’ perception

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