Search results for: accelerated aging
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1076

Search results for: accelerated aging

596 Proecological Antioxidants for Stabilisation of Polymeric Composites

Authors: A. Masek, M. Zaborski

Abstract:

Electrochemical oxidation of dodecyl gallate (lauryl gallate), the main monomer flavanol found in green tea, was investigated on platinum electrodes using cyclic voltammetry (CV) and differential pulse (DPV) methods. The rate constant, electron transfer coefficient and diffusion coefficients were determined for dodecyl gallate electrochemical oxidation. The oxidation mechanism proceeds in sequential steps related to the hydroxyl groups in the aromatic ring of dodecyl gallate. Confirmed antioxidant activity of lauryl gallate verified its use in polymers as an environment-friendly stabiliser to improve the resistance to aging of the elastomeric materials. Based on the energy change of the deformation, cross-linking density and time of the oxygen induction with the TG method, we confirmed the high antioxidant activity of lauryl gallate in polymers. Moreover, the research on biodegradation confirmed the environment-friendly influence of the antioxidant by increasing the susceptibility of the elastomeric materials to disintegration by mildew mushrooms.

Keywords: polymers, flavonoids, stabilization, ageing

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595 Electronic Media and Physical Activity of Primary School Children

Authors: Srna Jenko Miholic, Marta Borovec, Josipa Persun

Abstract:

The constant expansion of technology has further accelerated the development of media and vice versa. Although its promotion includes all kinds of interesting and positive sides, the poor functioning of the media is still being researched and proven. Young people, as well as children from the earliest age, resort to the media the most, so it is necessary to defend the role of adults as it were parents, teachers, and environment against virtual co-educators such as the media. The research aim of this study was to determine the time consumption of using electronic media by primary school children as well as their involvement in certain physical activities. Furthermore, to determine what is happening when parents restrict their children's access to electronic media and encourage them to participate in alternative contents during their leisure time. Result reveals a higher percentage of parents restrict their children's access to electronic media and then encourage children to socialize with family and friends, spend time outdoors, engage in physical activity, read books or learn something unrelated to school content even though it would not be children's favorite activity. The results highlight the importance of parental control when it comes to children's use of electronic media and the positive effects that parental control has in terms of encouraging children to be useful, socially desirable, physically active, and healthy activities.

Keywords: elementary school, digital media, leisure time, parents, physical engagement

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594 Effects of Applied Pressure and Heat Treatment on the Microstructure of Squeeze Cast Al-Si Alloy Were Examined

Authors: Mohamed Ben Amar, Henda Barhoumi, Hokia Siala, Foued Elhalouani

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The present contribution consists of a purely experimental investigation on the effect of Squeeze casting on the micro structural and mechanical propriety of Al-Si alloys destined to automotive industry. Accordingly, we have proceeding, by ourselves, to all the thermal treatment consisting of solution treatment at 540°C for 8h and aging at 160°C for 4h. The various thermal treatment, have been carried out in order to monitor the processes of formation and dissolution accompanying the solid state phase transformations as well as the resulting changes in the mechanical proprieties. The examination of the micrographs of the aluminum alloys reveals the dominant presence of dendrite. Concerning the mechanical characteristic the Vickers micro-hardness curve an increase as a function of the pressure. As well as the heat treatment increase mechanical propriety such that pressure and micro hardness. The curves have been explained in terms of structural hardening resulting from the various compounds formation.

Keywords: squeeze casting, process parameters, heat treatment, ductility, microstructure

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593 An Approach to Manage and Evaluate Asset Performance

Authors: Mohammed Saif Al-Saidi, John P. T. Mo

Abstract:

Modern engineering assets are complex and very high in value. They are expected to function for years to come, with ability to handle the change in technology and ageing modification. The aging of an engineering asset and continues increase of vendors and contractors numbers forces the asset operation management (or Owner) to design an asset system which can capture these changes. Furthermore, an accurate performance measurement and risk evaluation processes are highly needed. Therefore, this paper explores the nature of the asset management system performance evaluation for an engineering asset based on the System Support Engineering (SSE) principles. The research work explores the asset support system from a range of perspectives, interviewing managers from across a refinery organisation. The factors contributing to complexity of an asset management system are described in context which clusters them into several key areas. It is proposed that SSE framework may then be used as a tool for analysis and management of asset. The paper will conclude with discussion of potential application of the framework and opportunities for future research.

Keywords: asset management, performance, evaluation, modern engineering, System Support Engineering (SSE)

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592 Research of the Rotation Magnetic Field Current Driven Effect on Pulsed Plasmoid Acceleration of Electric Propulsion

Authors: X. F. Sun, X. D. Wen, L. J. Liu, C. C. Wu, Y. H. Jia

Abstract:

The field reversed closed magnetic field configuration plasmoid has a potential for large thrust and high power propulsion missions such as deep space exploration due to its high plasma density and larger azimuthal current, which will be a most competitive program for the next generation electric propulsion technology. Moreover, without the electrodes, it also has a long lifetime. Thus, the research on this electric propulsion technology is quite necessary. The plasmoid will be formatted and accelerated by applying a rotation magnetic field (RMF) method. And, the essence of this technology lies on the generation of the azimuthal electron currents driven by RMF. Therefore, the effect of RMF current on the plasmoid acceleration efficiency is a concerned problem. In the paper, the influences of the penetration process of RMF in plasma, the relations of frequency and amplitude of input RF power with current strength and the RMF antenna configuration on the plasmoid acceleration efficiency will be given by a two-fluid numerical simulation method. The results show that the radio-frequency and input power have remarkable influence on the formation and acceleration of plasmoid. These results will provide useful advice for the development, and optimized designing of field reversed configuration plasmoid thruster.

Keywords: rotation magnetic field, current driven, plasma penetration, electric propulsion

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591 Life-Saving Design Strategies for Nursing Homes and Long-Term Care Facilities

Authors: Jason M. Hegenauer, Nicholas Fucci

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In the late 1990s, a major deinstitutionalization movement of elderly patients took place, since which, the design of long-term care facilities has not been adequately analyzed in the United States. Over the course of the last 25 years, major innovations in construction methods, technology, and medicine have been developed, drastically changing the landscape of healthcare architecture. In light of recent events, and the expected increase in elderly populations with the aging of the baby-boomer generation, it is evident that reconsideration of these facilities is essential for the proper care of aging populations. The global response has been effective in stifling this pandemic; however, widespread disease still poses an imminent threat to the human race. Having witnessed the devastation Covid-19 has reaped throughout nursing homes and long-term care facilities, it is evident that the current strategies for protecting our most vulnerable populations are not enough. Light renovation of existing facilities and previously overlooked considerations for new construction projects can drastically lower the risk at nursing homes and long-term care facilities. A reconfigured entry sequence supplements several of the features which have been long-standing essentials of the design of these facilities. This research focuses on several aspects identified as needing improvement, including indoor environment quality, security measures incorporated into healthcare architecture and design, and architectural mitigation strategies for sick building syndrome. The results of this study have been compiled as 'best practices' for the design of future healthcare construction projects focused on the health, safety, and quality of life of the residents of these facilities. These design strategies, which can easily be implemented through renovation of existing facilities and new construction projects, minimize risk of infection and spread of disease while allowing routine functions to continue with minimal impact, should the need for future lockdowns arise. Through the current lockdown procedures, which were implemented during the Covid-19 pandemic, isolation of residents has caused great unrest and worry for family members and friends as they are cut off from their loved ones. At this time, data is still being reported, leaving infection and death rates inconclusive; however, recent projections in some states list long-term care facility deaths as high as 60% of all deaths in the state. The population of these facilities consists of residents who are elderly, immunocompromised, and have underlying chronic medical conditions. According to the Centers for Disease Control, these populations are particularly susceptible to infection and serious illness. The obligation to protect our most vulnerable population cannot be overlooked, and the harsh measures recently taken as a response to the Covid-19 pandemic prove that the design strategies currently utilized for doing so are inadequate.

Keywords: building security, healthcare architecture and design, indoor environment quality, new construction, sick building syndrome, renovation

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590 Bit Error Rate Monitoring for Automatic Bias Control of Quadrature Amplitude Modulators

Authors: Naji Ali Albakay, Abdulrahman Alothaim, Isa Barshushi

Abstract:

The most common quadrature amplitude modulator (QAM) applies two Mach-Zehnder Modulators (MZM) and one phase shifter to generate high order modulation format. The bias of MZM changes over time due to temperature, vibration, and aging factors. The change in the biasing causes distortion to the generated QAM signal which leads to deterioration of bit error rate (BER) performance. Therefore, it is critical to be able to lock MZM’s Q point to the required operating point for good performance. We propose a technique for automatic bias control (ABC) of QAM transmitter using BER measurements and gradient descent optimization algorithm. The proposed technique is attractive because it uses the pertinent metric, BER, which compensates for bias drifting independently from other system variations such as laser source output power. The proposed scheme performance and its operating principles are simulated using OptiSystem simulation software for 4-QAM and 16-QAM transmitters.

Keywords: automatic bias control, optical fiber communication, optical modulation, optical devices

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589 Influence of Tactile Symbol Size on Its Perceptibility in Consideration of Effect of Aging

Authors: T. Nishimura, K. Doi, H. Fujimoto, T. Wada

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We conducted perception experiments on tactile symbols to elucidate the impact of the size of these letters on the level of perceptibility. This study was based on the accessible design perspective and aimed at expanding the availability of tactile symbols for the visually impaired who are unable to read Braille characters. In particular, this study targeted people with acquired visual impairments as users of the tactile symbols. The subjects (young and elderly individuals) in this study had normal vision. They were asked to participate in the experiments to identify tactile symbols while unable to see their hand during the experiments. This study investigated the relation between the size and perceptibility of tactile symbols based on an examination using test pieces of these letters in different sizes. The results revealed that the error rates for both young and elderly subjects converged to almost 0% when 12 mm size tactile symbols were used. The findings also showed that the error rate was low and subjects could identify the symbols in 5 s when 16 mm size tactile symbols were introduced.

Keywords: accessible design, tactile sense, tactile symbols, bioinformatic

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588 The Spatial Equity Assessment of Community-Based Elderly Care Facilities in Old Neighborhood of Chongqing

Authors: Jiayue Zhao, Hongjuan Wu, Guiwen Liu

Abstract:

Old neighborhoods with a large elderly population depend on community-based elderly care facilities (community-based ECFs) for aging-in-place. Yet, due to scarce and scattered land, the facilities face inequitable distribution. This research uses spatial equity theory to measure the spatial equity of community-based ECFs in old neighborhoods. Field surveys gather granular data and methods, including coverage rate, Gini coefficient, Lorenz curve, and G2SFCA. The findings showed that coverage is substantial but does not indicate supply is a match to demand, nor does it imply superior accessibility. The key contributions are that structuring spatial equity framework considering elderly residents’ travel behavior. This study is dedicated to the international literature on spatial equity from the perspective of travel behavior and could provide valuable suggestions for the urban planning of old neighborhoods.

Keywords: community-based ECFs, elderly residents’ travel behavior, old neighborhoods, spatial equity

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587 Pubertal Development among 10-Year-Olds: The Role of Parent's Attachment Style

Authors: Hanit Ohana, Anat Scher

Abstract:

For decades, attachment research examined how mothers’ attachment styles shape parenting and specific aspects of child development. Only limited research addressed pubertal development from the perspective of attachment relationships. The current study focused on pubertal development at 10 years of age, as defined by Tanner (PDS), and examined the associations with both mothers’ and fathers’ attachment styles (ECR-S). Sixty-nine parents and their children from a medium SES participated in the study. It was found that whereas mothers’ attachment was not related to the child’s puberty development, fathers’ attachment was associated with their daughter’s pubertal development. Specifically, in girls, but not boys, advanced pubertal development was positively correlated with fathers’ avoidance (r = .37, p = 0.05), and negatively correlated with anxiety scores (r = -.36, p = 0.05). This result raises the possibility that for girls, a relationship with fathers may serve as a psychological stressor, and in turn, induce concerns regarding resources and availability of interpersonal support. Such processes may contribute to different reproductive timing and strategies, including delayed and accelerated pubertal development. As more data are collected, we will be able to address with more power the role of parent’s attachment in shaping the pubertal development of their young adolescents. Expanding the understanding of aspects of pubertal development –an important milestone of human development- and the possible linkages with parental attachment is important for researchers and clinicians.

Keywords: attachment style, children, gender, parents, puberty

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586 Smart City and the Elderly’s Subjective Well-Being

Authors: Wenlong Liu, Ru Zhang, Wangjie Li, Shenghui Sang

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The boom of smart cities in the age of population aging has caused concerns about the subjective well-being of the elderly. By employing the data from China Health and Retirement Longitudinal Study (CHARLS) 2015, this study uses an ordinary least square to analyze the influence of smart city development on the subjective well-being of the elderly in China. The results of this study suggest that smart cities will improve the life satisfaction of the elderly but reduce their happiness of them. In terms of the moderating effect, social capital negatively moderates the impact of the smart city on the subjective well-being of the elderly. Combined with the results of heterogeneous analysis, it is found that smart city has a stronger impact on the subjective well-being of the elderly with lower levels of personal social capital. To sum up, in the context of the country's vigorous promotion of smart city development, society and families should actively help the elderly to improve their social capital level, enhance the subjective well-being of the elderly, and alleviate the negative effects of smart city development, thereby improving the quality of life of the elderly.

Keywords: the elderly, smart city, social capital, subjective well-being

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585 Estimating Knowledge Flow Patterns of Business Method Patents with a Hidden Markov Model

Authors: Yoonjung An, Yongtae Park

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Knowledge flows are a critical source of faster technological progress and stouter economic growth. Knowledge flows have been accelerated dramatically with the establishment of a patent system in which each patent is required by law to disclose sufficient technical information for the invention to be recreated. Patent analysis, thus, has been widely used to help investigate technological knowledge flows. However, the existing research is limited in terms of both subject and approach. Particularly, in most of the previous studies, business method (BM) patents were not covered although they are important drivers of knowledge flows as other patents. In addition, these studies usually focus on the static analysis of knowledge flows. Some use approaches that incorporate the time dimension, yet they still fail to trace a true dynamic process of knowledge flows. Therefore, we investigate dynamic patterns of knowledge flows driven by BM patents using a Hidden Markov Model (HMM). An HMM is a popular statistical tool for modeling a wide range of time series data, with no general theoretical limit in regard to statistical pattern classification. Accordingly, it enables characterizing knowledge patterns that may differ by patent, sector, country and so on. We run the model in sets of backward citations and forward citations to compare the patterns of knowledge utilization and knowledge dissemination.

Keywords: business method patents, dynamic pattern, Hidden-Markov Model, knowledge flow

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584 Study of the Behavior of an Organic Coating Applied on Algerian Oil Tanker in Seawater

Authors: N. Hammouda, K. Belmokre

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The paints are used extensively today in the industry to protect the metallic structures of the aggressive environments. This work is devoted to the study of corrosion resistance and aging behavior of a paint coating providing external protection for oil tankers. To avoid problems related to corrosion of these vessels, two protection modes are provided: An electro chemical active protection (cathodic protection of the hull). A passive protection by external painting. Investigations are conducted using stationary and non-stationary electro chemical tools such as electro chemical impedance spectroscopy has allowed us to characterize the protective qualities of these films. The application of the EIS on our damaged in-situ painting shows the existence of several capacitive loops which is an indicator of the failure of our tested paint. Microscopic analysis (micrograph) helped bring essential elements in understanding the degradation of our paint condition and immersion training corrosion products.

Keywords: epoxy paints, electrochemical impedance spectroscopy, corrosion mechanisms, seawater

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583 Developing Norms for Sit and Reach Test in the Local Environment of Khyber Pakhtunkhwa, Pakistan

Authors: Hazratullah Khattak, Abdul Waheed Mughal, Inamullah Khattak

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This study is envisaged as vital contribution as it intends to develop norms for the Sit and Reach Test in the Local Environment of Khyber Pakhtunkhwa Pakistan, for the age group between 12-14 years which will be used to measure the flexibility level of early adolescents (12-14 years). Sit and Reach test was applied on 2000 volunteers, 400 subjects from each selected district (Five (5) Districts, Peshawar, Nowshera, Karak, Dera Ismail Khan and Swat (20% percent of the total 25 districts) using convenient sampling technique. The population for this study is comprised of all the early adolescents aging 12-14 years (Age Mean 13 + 0.63, Height 154 + 046, Weight 46 + 7.17, BMI 19 + 1.45) representing various public and private sectors educational institutions of the Khyber Pakhtunkhwa. As for as the norms developed for Sit and Reach test, the score below 6.8 inches comes in the category of poor, 6.9 to 9.6 inches (below Average), 9.7 to 10.8 inches (Average), 10.9 to 13 inches (Above average) and above 13 inches score is considered as Excellent.

Keywords: fitness, flexibility, norms, sit and reach

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582 Magnetic Treatment of Irrigation Water and Its Effect on Water Salinity

Authors: Muhammad Waqar Ashraf

Abstract:

The influence of magnetic field on the structure of water and aqueous solutions are similar and can alter the physical and chemical properties of water-dispersed systems. With the application of magnetic field, hydration of salt ions and other impurities slides down and improve the possible technological characteristics of the water. Magnetic field can enhance the characteristic of water i.e. better salt solubility, kinetic changes in salt crystallization, accelerated coagulation, etc. Gulf countries are facing critical problem due to depletion of water resources and increasing food demands to cover the human needs; therefore water shortage is being increasingly accepted as a major limitation for increased agricultural production and food security. In arid and semi-arid regions sustainable agricultural development is influenced to a great extent by water quality that might be used economically and effectively in developing agriculture programs. In the present study, the possibility of using magnetized water to desalinate the soil is accounted for the enhanced dissolving capacity of the magnetized water. Magnetic field has been applied to treat brackish water. The study showed that the impact of magnetic field on saline water is sustained up to three hours (with and without shaking). These results suggest that even low magnetic field can decrease the electrical conductivity and total dissolved solids which are good for the removal of salinity from the irrigated land by using magnetized water.

Keywords: magnetic treatment, saline water, hardness of water, removal of salinity

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581 Radiation Emission from Ultra-Relativistic Plasma Electrons in Short-Pulse Laser Light Interactions

Authors: R. Ondarza-Rovira, T. J. M. Boyd

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Intense femtosecond laser light incident on over-critical density plasmas has shown to emit a prolific number of high-order harmonics of the driver frequency, with spectra characterized by power-law decays Pm ~ m-p, where m denotes the harmonic order and p the spectral decay index. When the laser pulse is p-polarized, plasma effects do modify the harmonic spectrum, weakening the so-called universal decay with p=8/3 to p=5/3, or below. In this work, appeal is made to a single particle radiation model in support of the predictions from particle-in-cell (PIC) simulations. Using this numerical technique we further show that the emission radiated by electrons -that are relativistically accelerated by the laser field inside the plasma, after being expelled into vacuum, the so-called Brunel electrons is characterized not only by the plasma line but also by ultraviolet harmonic orders described by the 5/3 decay index. Results obtained from these simulations suggest that for ultra-relativistic light intensities, the spectral decay index is further reduced, with p now in the range 2/3 ≤ p ≤ 4/3. This reduction is indicative of a transition from the regime where Brunel-induced plasma radiation influences the spectrum to one dominated by bremsstrahlung emission from the Brunel electrons.

Keywords: ultra-relativistic, laser-plasma interactions, high-order harmonic emission, radiation, spectrum

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580 The New Contemporary Cross-Cultural Buddhist Woman and Her Attitude and Perception toward Motherhood

Authors: Szerena Vajkovszki

Abstract:

Among the relatively large volume of literature, the role and perception of women in Buddhism have been examined from various perspectives such as theology, history, anthropology, and feminism. When Buddhism spread to the West, women had a major role in its adaption and development. The meeting of different cultures and social structures had the fruit of a necessity to change. As Buddhism gained attention in the West, it produced a Buddhist feminist identity across national and ethnic boundaries. So globalization produced a contemporary cross-cultural Buddhist Women. The aim of the research is to find out the new role of such a Buddhist woman in aging societies. More precisely to understand what effect this contemporary Buddhist religion may have, direct or indirect, on fertility. Our worldwide aging society, especially in developed countries, including members of EU, raise sophisticated sociological and economic issues and challenges to be met. As declining fertility has outstanding influence underlying this trend, numerous studies have attempted to identify, describe, measure and interpret contributing factors of the fertility rate, out of which relatively few revealed the impact of religion. Among many religious guidelines, we can separate two major categories: direct and indirect. The aim of this research was to understand what are the most crucial identified (family values, gender related behaviors, religious sentiments) and not yet identified most influential contributing contemporary Buddhist religious factors. Above identifying these direct or indirect factors, it is also important to understand to what extent and how do they influence fertility, which requires a wider (inter-discipline) perspective. As proved by previous studies religion has also an influential role in health, mental state, well-being, working activity and many other components that are also related to fertility rates. All these components are inter-related, hence direct and indirect religious effects can only be well understood, if we figure out all necessary fields and their interaction. With the help of semi-structured opened interviews taking place in different countries, it was showed that indeed Buddhism has significant direct and indirect effect on fertility, hence the initial hypothesis was proved. However, the interviews showed an overall positive effect, the results could only serve for a general understanding about how Buddhism affects fertility. Evolution of Buddhism’s direct and indirect influence may vary in different nations and circumstances according to their specific environmental attributes. According to the local patterns, with special regard to women’s position and role in the society, outstandingly indirect influences could show diversifications. So it is advisory to investigate more for a deeper and clearer understanding of how Buddhism function in different socioeconomic circumstances. For example, in Hungary after the period of secularization more and more people tended to be attracted toward some transcendent values which could be an explanation for the rising number of Buddhists in the country. The present research could serve as a general starting point or a common basis for further specific national investigations how contemporary Buddhism affects fertility.

Keywords: contemporary Buddhism, cross-cultural woman, fertility, gender roles, religion

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579 Improving Research Collaborations in Medical Device Development in Korea from an SMEs’ Perspective

Authors: Yoon Chung Kim

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In this coming aging society, medical device industry is expected to become one of the major industries. Since developing medical devices usually requires technology convergence, research collaboration is important, especially for some small and medium enterprises (SMEs) that do not have enough R&D resources in each related field. Collaboration in medical device development has some unique properties. Since it requires convergence technology, collaboration with different fields, and different types of people are often required. Since it requires clinical test, the development process usually takes longer and collaboration with hospitals is also required. However, despite these importance and uniqueness, collaboration in medical device development has not yet been widely studied. Thus, our research focuses on investigating collaborations in medical device development. For our research, we conducted surveys and interviews, especially with SMEs’ perspective in Korea. The result and discussion will be presented with a major impact factors for collaboration result, as well as future strategies that will improve and strengthen collaboration process in medical devices.

Keywords: medical device, SME, research collaboration, development, clinical

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578 Governance, Risk Management, and Compliance Factors Influencing the Adoption of Cloud Computing in Australia

Authors: Tim Nedyalkov

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A business decision to move to the cloud brings fundamental changes in how an organization develops and delivers its Information Technology solutions. The accelerated pace of digital transformation across businesses and government agencies increases the reliance on cloud-based services. They are collecting, managing, and retaining large amounts of data in cloud environments makes information security and data privacy protection essential. It becomes even more important to understand what key factors drive successful cloud adoption following the commencement of the Privacy Amendment Notifiable Data Breaches (NDB) Act 2017 in Australia as the regulatory changes impact many organizations and industries. This quantitative correlational research investigated the governance, risk management, and compliance factors contributing to cloud security success. The factors influence the adoption of cloud computing within an organizational context after the commencement of the NDB scheme. The results and findings demonstrated that corporate information security policies, data storage location, management understanding of data governance responsibilities, and regular compliance assessments are the factors influencing cloud computing adoption. The research has implications for organizations, future researchers, practitioners, policymakers, and cloud computing providers to meet the rapidly changing regulatory and compliance requirements.

Keywords: cloud compliance, cloud security, data governance, privacy protection

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577 Study of Electron Cyclotron Resonance Acceleration by Cylindrical TE₀₁₁ Mode

Authors: Oswaldo Otero, Eduardo A. Orozco, Ana M. Herrera

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In this work, we present results from analytical and numerical studies of the electron acceleration by a TE₀₁₁ cylindrical microwave mode in a static homogeneous magnetic field under electron cyclotron resonance (ECR) condition. The stability of the orbits is analyzed using the particle orbit theory. In order to get a better understanding of the interaction wave-particle, we decompose the azimuthally electric field component as the superposition of right and left-hand circular polarization standing waves. The trajectory, energy and phase-shift of the electron are found through a numerical solution of the relativistic Newton-Lorentz equation in a finite difference method by the Boris method. It is shown that an electron longitudinally injected with an energy of 7 keV in a radial position r=Rc/2, being Rc the cavity radius, is accelerated up to energy of 90 keV by an electric field strength of 14 kV/cm and frequency of 2.45 GHz. This energy can be used to produce X-ray for medical imaging. These results can be used as a starting point for study the acceleration of electrons in a magnetic field changing slowly in time (GYRAC), which has some important applications as the electron cyclotron resonance ion proton accelerator (ECR-IPAC) for cancer therapy and to control plasma bunches with relativistic electrons.

Keywords: Boris method, electron cyclotron resonance, finite difference method, particle orbit theory, X-ray

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576 Heat Pipe Production and Life Performance Tests in Geosynchronous Telecom Satellites

Authors: Erkam Arslantas

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Heat pipes one of the thermal control elements are used in communication satellites. A selection of the heat pipes of satellite thermal design will be emphasized how important and effective it is. In this article, manufacturing and performance control tests of heat pipes are reviewed from the current literature. The heat pipe is expected to function efficiently during all missions of the spacecraft from Beginning of Life (BOL) to End of Life (EOL). There are many parameters that are evaluated in manufacturing and performance control tests of the heat pipes which are used in satellites. These parameters are pressure design, leakage, noncondensable gas level (N.C.G), sine vibration, shock and static load capabilities, aging, bending, proof, final test etc. These parameters will be explained separately for the heat pipes in this review article and young researches working on the thermal control system of Geosynchronous Satellites systems can find easily related information in this article.

Keywords: communication satellite, heat pipe, performance test, thermal control

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575 50+ Customers' Behavior in the Financial Market of the Czech Republic

Authors: K. Matušínská, H. Starzyczná, M. Stoklasa

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The paper deals with behaviour of the segment 50+ in the financial market in the Czech Republic. This segment could be said as the strong market power and it can be a crucial business potential for financial business units. The main defined objective of this paper is analysis of the customers´ behaviour of the segment 50-60 years in the financial market in the Czech Republic and proposal making of the suitable marketing approach to satisfy their demands in the area of product, price, distribution and marketing communication policy. This paper is based on data from one part of primary marketing research. Paper determinates the basic problem areas as well as definition of financial services marketing, defining the primary research problem, hypothesis and primary research methodology. Finally suitable marketing approach to selected sub-segment at age of 50-60 years is proposed according to marketing research findings.

Keywords: population aging in the Czech Republic, segment 50-60 years, financial services marketing, marketing research, marketing approach

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574 Design of Bidirectional PFC Totem Pole for OBC

Authors: Dihia Sidi Ahmed, Hiba Mili

Abstract:

In the current context of European and global energy transition and the accelerated integration of renewable energies, the transition to electric vehicles with V2X (Vehicle-to-anything) charging options is favored to enhance the power grid and to serve as an energy supply in peak demand periods. Regarding the fast development of EV charging infrastructures, a cost-effective and efficient solution is required to meet OEM's (Original Equipment Manufacturers) needs. In this context, a single-phase 7.4 kW bidirectional on-board charger with G2V, V2G and V2L capabilities has been developed to support faster charging. The proposed architecture consists of two power stages. A Totem Pole PFC stage works as a rectifier in G2V with a unity power factor and as an inverter in V2G and V2L. The second stage is a CLLLC resonant converter selected to achieve higher energy efficiency, ZVS and ZCS and cost-effectiveness. SiC technology is used for switching devices to maximize power efficiency by lowering switching losses and to improve power density by minimizing the size of filters and passive components. Pulse frequency modulation (PWM) control is used for the Totem Pole PFC and pulse frequency modulation (PFM) control is used for the CLLC stage to control the stage gain in both energy transfer directions. In the context of validating the topology, this paper elaborates the simulation and the performance evaluation of the first power stage in the Matlab/Simulink environment.

Keywords: V2G, V2X, OBC, CLLC.

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573 An Assessment of Self-Perceived Health after the Death of a Spouse among the Elderly

Authors: Shu-Hsi Ho

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The problems of aging and number of widowed peers gradually rise in Taiwan. It is worth to concern the related issues for elderly after the death of a spouse. Hence, this study is to examine the impact of spousal death on the surviving spouse’s self-perceived health and mental health for the elderly in Taiwan. A cross section data design and ordered logistic regression models are applied to investigate whether marriage is associated significantly to self-perceived health and mental health for the widowed older Taiwanese. The results indicate that widowed marriage shows significant negative effects on self-perceived health and mental health regardless of widows or widowers. Among them, widows might be more likely to show worse mental health than widowers. The belief confirms that marriage provides effective sources to promote self-perceived health and mental health, particularly for females. In addition, since the social welfare system is not perfect in Taiwan, the findings also suggest that family and social support reveal strongly association with the self-perceived health and mental health for the widows and widowers elderly.

Keywords: logistic regression models, self-perceived health, widow, widower

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572 Quantification of Polychlorinated Biphenyls (PCBs) in Soil Samples of Electrical Power Substations from Different Cities in Nigeria

Authors: Omasan Urhie Urhie, Adenipekun C. O, Eke W., Ogwu K., Erinle K. O

Abstract:

Polychlorinated Biphenyls (PCBs) are Persistent organic pollutants (POPs) that are very toxic; they possess ability to accumulate in soil and in human tissues hence resulting in health issues like birth defect, reproductive disorder and cancer. The air is polluted by PCBs through volatilization and dispersion; they also contaminate soil and sediments and are not easily degraded. Soil samples were collected from a depth of 0-15 cm from three substations (Warri, Ughelli and Ibadan) of Power Holding Company of Nigeria (PHCN) where old transformers were dumped in Nigeria. Extraction and cleanup of soil samples were conducted using Accelerated Solvent Extraction (ASE) with Pressurized Liquid extraction (PLE). The concentration of PCBs was determined using gsas chromatography/mass spectrometry (GC/MS). Mean total PCB concentrations in the soil samples increased in the order Ughelli ˂ Ibadan˂ Warri, 2.457757ppm Ughelli substation 4.198926ppm, for Ibadan substation and 14.05065ppm at Warri substation. In the Warri samples, PCB-167 was the most abundant at about 30% (4.28086ppm) followed by PCB-157 at about 20% (2.77871), of the total PCB concentrations (14.05065ppm). Of the total PCBs in the Ughelli and Ibadan samples, PCB-156 was the most abundant at about 44% and 40%, respectively. This study provides a baseline report on the presence of PCBs in the vicinity of abandoned electrical power facilities in different cities in Nigeria.

Keywords: polychlorintated biphenyls, persistent organic pollutants, soil, transformer

Procedia PDF Downloads 114
571 Effects of Aging on Thermal Properties of Some Improved Varieties of Cassava (Manihot Esculenta) Roots

Authors: K. O. Oriola, A. O. Raji, O. E. Akintola, O. T. Ismail

Abstract:

Thermal properties of roots of three improved cassava varieties (TME419, TMS 30572, and TMS 0326) were determined on samples harvested at 12, 15 and 18 Months After Planting (MAP) conditioned to moisture contents of 50, 55, 60, 65, 70% (wb). Thermal conductivity at 12, 15 and 18 MAP ranged 0.4770 W/m.K to 0.6052W/m.K; 0.4804 W/m.K to 0.5530 W/m.K and 0.3764 to 0.6102 W/m.K respectively, thermal diffusivity from 1.588 to 2.426 x 10-7m2/s; 1.290 to 2.010 x 10-7m2/s and 0.1692 to 4.464 x 10-7m2/s and specific heat capacity from 2.3626 to 3.8991 kJ/kg.K; 1.8110 to 3.9703 kJ/kgK and 1.7311 to 3.8830 kJ/kg.K respectively within the range of moisture content studied across the varieties. None of the samples over the ages studied showed similar or definite trend in variation with others across the moisture content. However, second order polynomial models fitted all the data. Age on the other hand had a significant effect on the three thermal properties studied for TME 419 but not on thermal conductivity of TMS30572 and specific heat capacity of TMS 0326. Information obtained will provide better insight into thermal processing of cassava roots into stable products.

Keywords: thermal conductivity, thermal diffusivity, specific heat capacity, moisture content, tuber age

Procedia PDF Downloads 493
570 Accelerated Structural Reliability Analysis under Earthquake-Induced Tsunamis by Advanced Stochastic Simulation

Authors: Sai Hung Cheung, Zhe Shao

Abstract:

Recent earthquake-induced tsunamis in Padang, 2004 and Tohoku, 2011 brought huge losses of lives and properties. Maintaining vertical evacuation systems is the most crucial strategy to effectively reduce casualty during the tsunami event. Thus, it is of our great interest to quantify the risk to structural dynamic systems due to earthquake-induced tsunamis. Despite continuous advancement in computational simulation of the tsunami and wave-structure interaction modeling, it still remains computationally challenging to evaluate the reliability (or its complement failure probability) of a structural dynamic system when uncertainties related to the system and its modeling are taken into account. The failure of the structure in a tsunami-wave-structural system is defined as any response quantities of the system exceeding specified thresholds during the time when the structure is subjected to dynamic wave impact due to earthquake-induced tsunamis. In this paper, an approach based on a novel integration of the Subset Simulation algorithm and a recently proposed moving least squares response surface approach for stochastic sampling is proposed. The effectiveness of the proposed approach is discussed by comparing its results with those obtained from the Subset Simulation algorithm without using the response surface approach.

Keywords: response surface model, subset simulation, structural reliability, Tsunami risk

Procedia PDF Downloads 355
569 A Randomized, Controlled Trial to Test Habit Formation Theory for Low Intensity Physical Exercise Promotion in Older Adults

Authors: Patrick Louie Robles, Jerry Suls, Ciaran Friel, Mark Butler, Samantha Gordon, Frank Vicari, Joan Duer-Hefele, Karina W. Davidson

Abstract:

Physical activity guidelines focus on increasing moderate-intensity activity for older adults, but adherence to recommendations remains low. This is despite the fact that scientific evidence finds increasing physical activity is positively associated with health benefits. Behavior change techniques (BCTs) have demonstrated some effectiveness in reducing sedentary behavior and promoting physical activity. This pilot study uses a personalized trials (N-of-1) design, delivered virtually, to evaluate the efficacy of using five BCTs in increasing low-intensity physical activity (by 2,000 steps of walking per day) in adults aged 45-75 years old. The 5 BCTs described in habit formation theory are goal setting, action planning, rehearsal, rehearsal in a consistent context, and self-monitoring. The study recruited health system employees in the target age range who had no mobility restrictions and expressed interest in increasing their daily activity by a minimum of 2,000 steps per day at least five days per week. Participants were sent a Fitbit Charge 4 fitness tracker with an established study account and password. Participants were recommended to wear the Fitbit device 24/7 but were required to wear it for a minimum of ten hours per day. Baseline physical activity was measured by Fitbit for two weeks. Participants then engaged remotely with a clinical research coordinator to establish a “walking plan” that included a time and day interval (e.g., between 7am -8am on Monday-Friday), a location for the walk (e.g., park), and how much time the plan would need to achieve a minimum of 2,000 steps over their baseline average step count (20 minutes). All elements of the walking plan were required to remain consistent throughout the study. In the 10-week intervention phase of the study, participants received all five BCTs in a single, time-sensitive text message. The text message was delivered 30 minutes prior to the established walk time and signaled participants to begin walking when the context (i.e., day of the week, time of day) they pre-selected is encountered. Participants were asked to log both the start and conclusion of their activity session by pressing a button on the Fitbit tracker. Within 30 minutes of the planned conclusion of the activity session, participants received a text message with a link to a secure survey. Here, they noted whether they engaged in the BCTs when prompted and completed an automaticity survey to identify how “automatic” their walking behavior had become. At the end of their trial, participants received a personalized summary of their step data over time, helping them learn more about their responses to the five BCTs. Whether the use of these 5 ‘habit formation’ BCTs in combination elicits a change in physical activity behavior among older adults will be reported. This study will inform the feasibility of a virtually-delivered N-of-1 study design to effectively promote physical activity as a component of healthy aging.

Keywords: aging, exercise, habit, walking

Procedia PDF Downloads 119
568 Analysis of Ecological Footprint of Residents for Urban Spatial Restructuring

Authors: Taehyun Kim, Hyunjoo Park, Taehyun Kim

Abstract:

Since the rapid economic development, Korea has recently entered a period of low growth due to population decline and aging. Due to the urbanization around the metropolitan area and the hollowing of local cities, the ecological capacity of a city is decreasing while ecological footprints are increasing, requiring a compact space plan for maintaining urban functions. The purpose of this study is to analyze the relationship between urban spatial structure and residents' ecological footprints for sustainable spatial planning. To do this, we try to analyze the relationship between intra-urban spatial structure, such as net/gross density and service accessibility, and resident ecological footprints of food, housing, transportation, goods and services through survey and structural equation modeling. The results of the study will be useful in establishing an implementation plan for sustainable development goals (SDGs), especially for sustainable cities and communities (SDG 11) and responsible consumption and production (SDG 12) in the future.

Keywords: ecological footprint, structural equation modeling, survey, sustainability, urban spatial structure

Procedia PDF Downloads 243
567 Studying the Behavior of Asphalt Mix and Their Properties in the Presence of Nano Materials

Authors: Aman Patidar, Dipankar Sarkar, Manish Pal

Abstract:

Due to rapid development, increase in the traffic load, higher traffic volume and seasonal variation in temperature, asphalt pavement shows distresses like rutting, fatigue and thermal cracking etc. because of this pavement fails during service life so that bitumen needs to be modified with some additive. In this study VG30 grade bitumen modify with addition of nanosilica with 1% to 5% (increment of 1%) by weight of bitumen. Hot mix asphalt (HMA) have higher mixing, laying and rolling temperatures which leads to higher consumption of fuel. To address this issue, a nano material named ZycoTherm which is chemical warm mix asphalt (WMA) additive is added to bitumen. Nanosilica modification (NSMB) results in the increase in stability compared to unmodified bitumen (UMB). WMA modified mix shows slightly higher stability than UMB and NSMB in a lower bitumen content. The Retained stability and tensile strength ratio (TSR) is more than 75% and 80% respectively for both mixes. Nanosilica with WMA has more resistant to temperature susceptibility, moisture susceptibility and short term aging than NSMB.

Keywords: HMA, nanosilica, NSMB, temperature, TSR, UMB, WMA

Procedia PDF Downloads 285