Search results for: light gauge steel–concrete hybrid structure
Commenced in January 2007
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Paper Count: 14848

Search results for: light gauge steel–concrete hybrid structure

2338 Use Multiphysics Simulations and Resistive Pulse Sensing to Study the Effect of Metal and Non-Metal Nanoparticles in Different Salt Concentration

Authors: Chun-Lin Chiang, Che-Yen Lee, Yu-Shan Yeh, Jiunn-Haur Shaw

Abstract:

Wafer fabrication is a critical part of the semiconductor process, when the finest linewidth with the improvement of technology continues to decline and the structure development from 2D towards to 3D. The nanoparticles contained in the slurry or in the ultrapure water which used for cleaning have a large influence on the manufacturing process. Therefore, semiconductor industry is hoping to find a viable method for on-line detection the nanoparticles size and concentration. The resistive pulse sensing technology is one of the methods that may cover this question. As we know that nanoparticles properties of material differ significantly from their properties at larger length scales. So, we want to clear that the metal and non-metal nanoparticles translocation dynamic when we use the resistive pulse sensing technology. In this study we try to use the finite element method that contains three governing equations to do multiphysics coupling simulations. The Navier-Stokes equation describes the laminar motion, the Nernst-Planck equation describes the ion transport, and the Poisson equation describes the potential distribution in the flow channel. To explore that the metal nanoparticles and the non-metal nanoparticles in different concentration electrolytes, through the nanochannel caused by ion current changes. Then the reliability of the simulation results was verified by resistive pulse sensing test. The existing results show that the lower ion concentration, the greater effect of nanoparticles on the ion concentration in the nanochannel. The conductive spikes are correlated with nanoparticles surface charge. Then we can be concluded that in the resistive pulse sensing technique, the ion concentration in the nanochannel and nanoparticle properties are important for the translocation dynamic, and they have the interactions.

Keywords: multiphysics simulations, resistive pulse sensing, nanoparticles, nanochannel

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2337 Hepatoprotective Evaluation of Potent Antioxidant Fraction from Urtica dioica L.: In vitro and In vivo Studies

Authors: Bhuwan C. Joshi, Atish Prakash, Ajudhia N. Kalia

Abstract:

Ethnopharmacological relevance: The plant Urtica dioica L. (Urticaceae) is used in various diseases including hepatic ailments. Traditionally, the leaves and roots of the plant are used in jaundice. Objective: The aim of the present work was to evaluate hepatoprotective potential of potent antioxidant from Urtica dioica L. against CCl4 induced hepatotoxicity in-vitro and in-vivo model. Materials and methods: Antioxidant activity of hydro alcoholic extract and its fractions petroleum ether fraction (PEF), ethyl acetate fraction (EAF), n-butanol fraction (NBF) and aqueous fraction (AF) were determined by DPPH radicals scavenging assay. Fractions were subjected to in-vitro cell line study. Further, the most potent fraction (EAF) was subjected to in-vivo study. The in-vivo hepatoprotective active fraction was chromatographed on silica column to isolate the bioactive constituent(s). Structure elucidation was done by using various spectrophotometric techniques like UV, IR, 1H NMR, 13C NMR and MS spectroscopy. Results and conclusion: The ethyl acetate fraction (EAF) of Urtica. dioica L. possessed the potent antioxidant activity viz. DPPH (IC50 78.99 ± 0.17 µg/ml). The in-vitro cell line study showed EAF prevented the cell damage. The EAF significantly attenuated the increased liver enzymes activities in serum and tissue. Column chromatography of most potent antioxidant fraction (EAF) leads to the isolation of 4-hydroxy-3-methoxy cinnamic acid which is responsible for its hepatoprotective potential. Hence, the present study suggests that EAF has significant antioxidant and hepatoprotective potential on CCl4 induced hepatotoxicity in-vitro and in-vivo.

Keywords: Urtica dioica L., antioxidant, HepG2 cell line, hepatoprotective

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2336 Partial M-Sequence Code Families Applied in Spectral Amplitude Coding Fiber-Optic Code-Division Multiple-Access Networks

Authors: Shin-Pin Tseng

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Nowadays, numerous spectral amplitude coding (SAC) fiber-optic code-division-multiple-access (FO-CDMA) techniques were appealing due to their capable of providing moderate security and relieving the effects of multiuser interference (MUI). Nonetheless, the performance of the previous network is degraded due to fixed in-phase cross-correlation (IPCC) value. Based on the above problems, a new SAC FO-CDMA network using partial M-sequence (PMS) code is presented in this study. Because the proposed PMS code is originated from M-sequence code, the system using the PMS code could effectively suppress the effects of MUI. In addition, two-code keying (TCK) scheme can applied in the proposed SAC FO-CDMA network and enhance the whole network performance. According to the consideration of system flexibility, simple optical encoders/decoders (codecs) using fiber Bragg gratings (FBGs) were also developed. First, we constructed a diagram of the SAC FO-CDMA network, including (N/2-1) optical transmitters, (N/2-1) optical receivers, and one N×N star coupler for broadcasting transmitted optical signals to arrive at the input port of each optical receiver. Note that the parameter N for the PMS code was the code length. In addition, the proposed SAC network was using superluminescent diodes (SLDs) as light sources, which then can save a lot of system cost compared with the other FO-CDMA methods. For the design of each optical transmitter, it is composed of an SLD, one optical switch, and two optical encoders according to assigned PMS codewords. On the other hand, each optical receivers includes a 1 × 2 splitter, two optical decoders, and one balanced photodiode for mitigating the effect of MUI. In order to simplify the next analysis, the some assumptions were used. First, the unipolarized SLD has flat power spectral density (PSD). Second, the received optical power at the input port of each optical receiver is the same. Third, all photodiodes in the proposed network have the same electrical properties. Fourth, transmitting '1' and '0' has an equal probability. Subsequently, by taking the factors of phase‐induced intensity noise (PIIN) and thermal noise, the corresponding performance was displayed and compared with the performance of the previous SAC FO-CDMA networks. From the numerical result, it shows that the proposed network improved about 25% performance than that using other codes at BER=10-9. This is because the effect of PIIN was effectively mitigated and the received power was enhanced by two times. As a result, the SAC FO-CDMA network using PMS codes has an opportunity to apply in applications of the next-generation optical network.

Keywords: spectral amplitude coding, SAC, fiber-optic code-division multiple-access, FO-CDMA, partial M-sequence, PMS code, fiber Bragg grating, FBG

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2335 Efficiency and Scale Elasticity in Network Data Envelopment Analysis: An Application to International Tourist Hotels in Taiwan

Authors: Li-Hsueh Chen

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Efficient operation is more and more important for managers of hotels. Unlike the manufacturing industry, hotels cannot store their products. In addition, many hotels provide room service, and food and beverage service simultaneously. When efficiencies of hotels are evaluated, the internal structure should be considered. Hence, based on the operational characteristics of hotels, this study proposes a DEA model to simultaneously assess the efficiencies among the room production division, food and beverage production division, room service division and food and beverage service division. However, not only the enhancement of efficiency but also the adjustment of scale can improve the performance. In terms of the adjustment of scale, scale elasticity or returns to scale can help to managers to make decisions concerning expansion or contraction. In order to construct a reasonable approach to measure the efficiencies and scale elasticities of hotels, this study builds an alternative variable-returns-to-scale-based two-stage network DEA model with the combination of parallel and series structures to explore the scale elasticities of the whole system, room production division, food and beverage production division, room service division and food and beverage service division based on the data of international tourist hotel industry in Taiwan. The results may provide valuable information on operational performance and scale for managers and decision makers.

Keywords: efficiency, scale elasticity, network data envelopment analysis, international tourist hotel

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2334 Probability-Based Damage Detection of Structures Using Model Updating with Enhanced Ideal Gas Molecular Movement Algorithm

Authors: M. R. Ghasemi, R. Ghiasi, H. Varaee

Abstract:

Model updating method has received increasing attention in damage detection structures based on measured modal parameters. Therefore, a probability-based damage detection (PBDD) procedure based on a model updating procedure is presented in this paper, in which a one-stage model-based damage identification technique based on the dynamic features of a structure is investigated. The presented framework uses a finite element updating method with a Monte Carlo simulation that considers the uncertainty caused by measurement noise. Enhanced ideal gas molecular movement (EIGMM) is used as the main algorithm for model updating. Ideal gas molecular movement (IGMM) is a multiagent algorithm based on the ideal gas molecular movement. Ideal gas molecules disperse rapidly in different directions and cover all the space inside. This is embedded in the high speed of molecules, collisions between them and with the surrounding barriers. In IGMM algorithm to accomplish the optimal solutions, the initial population of gas molecules is randomly generated and the governing equations related to the velocity of gas molecules and collisions between those are utilized. In this paper, an enhanced version of IGMM, which removes unchanged variables after specified iterations, is developed. The proposed method is implemented on two numerical examples in the field of structural damage detection. The results show that the proposed method can perform well and competitive in PBDD of structures.

Keywords: enhanced ideal gas molecular movement (EIGMM), ideal gas molecular movement (IGMM), model updating method, probability-based damage detection (PBDD), uncertainty quantification

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2333 Planning Fore Stress II: Study on Resiliency of New Architectural Patterns in Urban Scale

Authors: Amir Shouri, Fereshteh Tabe

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Master planning and urban infrastructure’s thoughtful and sequential design strategies will play the major role in reducing the damages of natural disasters, war and or social/population related conflicts for cities. Defensive strategies have been revised during the history of mankind after having damages from natural depressions, war experiences and terrorist attacks on cities. Lessons learnt from Earthquakes, from 2 world war casualties in 20th century and terrorist activities of all times. Particularly, after Hurricane Sandy of New York in 2012 and September 11th attack on New York’s World Trade Centre (WTC) in 21st century, there have been series of serious collaborations between law making authorities, urban planners and architects and defence related organizations to firstly, getting prepared and/or prevent such activities and secondly, reduce the human loss and economic damages to minimum. This study will work on developing a model of planning for New York City, where its citizens will get minimum impacts in threat-full time with minimum economic damages to the city after the stress is passed. The main discussion in this proposal will focus on pre-hazard, hazard-time and post-hazard transformative policies and strategies that will reduce the “Life casualties” and will ease “Economic Recovery” in post-hazard conditions. This proposal is going to scrutinize that one of the key solutions in this path might be focusing on all overlaying possibilities on architectural platforms of three fundamental infrastructures, the transportation, the power related sources and defensive abilities on a dynamic-transformative framework that will provide maximum safety, high level of flexibility and fastest action-reaction opportunities in stressful periods of time. “Planning Fore Stress” is going to be done in an analytical, qualitative and quantitative work frame, where it will study cases from all over the world. Technology, Organic Design, Materiality, Urban forms, city politics and sustainability will be discussed in deferent cases in international scale. From the modern strategies of Copenhagen for living friendly with nature to traditional approaches of Indonesian old urban planning patterns, the “Iron Dome” of Israel to “Tunnels” in Gaza, from “Ultra-high-performance quartz-infused concrete” of Iran to peaceful and nature-friendly strategies of Switzerland, from “Urban Geopolitics” in cities, war and terrorism to “Design of Sustainable Cities” in the world, will all be studied with references and detailed look to analysis of each case in order to propose the most resourceful, practical and realistic solutions to questions on “New City Divisions”, “New City Planning and social activities” and “New Strategic Architecture for Safe Cities”. This study is a developed version of a proposal that was announced as winner at MoMA in 2013 in call for ideas for Rockaway after Sandy Hurricane took place.

Keywords: urban scale, city safety, natural disaster, war and terrorism, city divisions, architecture for safe cities

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2332 Unionisation, Participation and Democracy: Forms of Convergence and Divergence between Union Membership and Civil and Political Activism in European Countries

Authors: Silvia Lucciarini, Antonio Corasaniti

Abstract:

The issue of democracy in capitalist countries has once again become the focus of debate in recent years. A number of socio-economic and political tensions have triggered discussion of this topic from various perspectives and disciplines. Political developments, the rise of both right-wing parties and populism and the constant growth of inequalities in a context of welfare downsizing, have led scholars to question if European capitalist countries are really capable of creating and redistributing resources and look for elements that might make democratic capital in European countries more dense. The aim of the work is to shed light on the trajectories, intensity and convergence or divergence between political and associative participation, on one hand, and organization, on the other, as these constitute two of the main points of connection between the norms, values and actions that bind citizens to the state. Using the European Social Survey database, some studies have sought to analyse degrees of unionization by investigating the relationship between systems of industrial relations and vulnerable groups (in terms of value-oriented practices or political participation). This paper instead aims to investigate the relationship between union participation and civil/political participation, comparing union members and non-members and then distinguishing between employees and self-employed professionals to better understand participatory behaviors among different workers. The first component of the research will employ a multilinear logistic model to examine a sample of 10 countries selected according to a grid that combines the industrial relations models identified by Visser (2006) and the Welfare State systems identified by Esping-Andersen (1990). On the basis of this sample, we propose to compare the choices made by workers and their propensity to join trade unions, together with their level of social and political participation, from 2002 to 2016. In the second component, we aim to verify whether workers within the same system of industrial relations and welfare show a similar propensity to engage in civil participation through political bodies and associations, or if instead these tendencies take on more specific and varied forms. The results will allow us to see: (1) if political participation is higher among unionized workers than it is among the non-unionized. (2) what are the differences in unionisation and civil/political participation between self-employed, temporary and full-time employees and (3) whether the trajectories within industrial relations and welfare models display greater inclusiveness and participation, thereby confirming or disproving the patterns that have been documented among the different European countries.

Keywords: union membership, participation, democracy, industrial relations, welfare systems

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2331 Benzenepropanamine Analogues as Non-detergent Microbicidal Spermicide for Effective Pre-exposure Prophylaxis

Authors: Veenu Bala, Yashpal S. Chhonker, Bhavana Kushwaha, Rabi S. Bhatta, Gopal Gupta, Vishnu L. Sharma

Abstract:

According to UNAIDS 2013 estimate nearly 52% of all individuals living with HIV are now women of reproductive age (15–44 years). Seventy-five percent cases of HIV acquisition are through heterosexual contacts and sexually transmitted infections (STIs), attributable to unsafe sexual behaviour. Each year, an estimated 500 million people acquire atleast one of four STIs: chlamydia, gonorrhoea, syphilis and trichomoniasis. Trichomonas vaginalis (TV) is exclusively sexually transmitted in adults, accounting for 30% of STI cases and associated with pelvic inflammatory disease (PID), vaginitis and pregnancy complications in women. TV infection resulted in impaired vaginal milieu, eventually favoring HIV transmission. In the absence of an effective prophylactic HIV vaccine, prevention of new infections has become a priority. It was thought worthwhile to integrate HIV prevention and reproductive health services including unintended pregnancy protection for women as both are related with unprotected sex. Initially, nonoxynol-9 (N-9) had been proposed as a spermicidal agent with microbicidal activity but on the contrary it increased HIV susceptibility due to surfactant action. Thus, to accomplish an urgent need of novel woman controlled non-detergent microbicidal spermicides benzenepropanamine analogues have been synthesized. At first, five benzenepropanamine-dithiocarbamate hybrids have been synthesized and evaluated for their spermicidal, anti-Trichomonas and anti-fungal activities along with safety profiling to cervicovaginal cells. In order to further enhance the scope of above study benzenepropanamine was hybridized with thiourea as to introduce anti-HIV potential. The synthesized hybrid molecules were evaluated for their reverse transcriptase (RT) inhibition, spermicidal, anti-Trichomonas and antimicrobial activities as well as their safety against vaginal flora and cervical cells. simulated vaginal fluid (SVF) stability and pharmacokinetics of most potent compound versus N-9 was examined in female Newzealand (NZ) rabbits to observe its absorption into systemic circulation and subsequent exposure in blood plasma through vaginal wall. The study resulted in the most promising compound N-butyl-4-(3-oxo-3-phenylpropyl) piperazin-1-carbothioamide (29) exhibiting better activity profile than N-9 as it showed RT inhibition (72.30 %), anti-Trichomonas (MIC, 46.72 µM against MTZ susceptible and MIC, 187.68 µM against resistant strain), spermicidal (MEC, 0.01%) and antifungal activity (MIC, 3.12–50 µg/mL) against four fungal strains. The high safety against vaginal epithelium (HeLa cells) and compatibility with vaginal flora (lactobacillus), SVF stability and least vaginal absorption supported its suitability for topical vaginal application. Docking study was performed to gain an insight into the binding mode and interactions of the most promising compound, N-butyl-4-(3-oxo-3-phenylpropyl) piperazin-1-carbothioamide (29) with HIV-1 Reverse Transcriptase. The docking study has revealed that compound (29) interacted with HIV-1 RT similar to standard drug Nevirapine. It may be concluded that hybridization of benzenepropanamine and thiourea moiety resulted into novel lead with multiple activities including RT inhibition. A further lead optimization may result into effective vaginal microbicides having spermicidal, anti-Trichomonas, antifungal and anti-HIV potential altogether with enhanced safety to cervico-vaginal cells in comparison to Nonoxynol-9.

Keywords: microbicidal, nonoxynol-9, reverse transcriptase, spermicide

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2330 The Factors Affecting on Promoting Productivity from Nurses' View

Authors: Mahnaz Sanjari, Sedigheh Salemi, Mohammad Mirzabeigi

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Nowadays, the world is facing a crisis of workforce and one of the most striking examples is the shortage of nurses. Nursing workforce productivity is related by various factors such as absenteeism, professional effectiveness and quality care. This cross-sectional study was conducted in 700 nurses who work in government hospitals from 35 hospitals of 9 provinces in Iran. The study was approved by the Nursing Council and was carried out with the authorization of the Research Ethics Committee. The questionnaire included 33 questions and 4 sub categories such as human resource, education and management. The reliability was evaluated by Cronbach's alpha (α=0/85). Statistical analyzes were performed, using SPSS version 16. The result showed that nurses emphasized on "respect to nurse-to-bed ratio" and less importance item was "using less experienced nurse". In addition, another important factor in clinical productivity is "Proper physical structure and amenities","good communication with colleagues" and "having good facilities". Also, "human resources at all levels of standard", "promoting on merit" and "well defined relationship in health system" are another important factors in productivity from nurse` view. The main managerial factor is "justice between employees" and the main educational component of productivity is “updating nursing knowledge”. The results show that more than half of the participants emphasized on the management and educational factors. Productivity as one of the main part of the health care quality leads to appropriate use of human and organizational resources, reduce cost services, and organizational development.

Keywords: productivity, nursing services, workforce, cost services

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2329 Well-Being in the Workplace: Do Christian Leaders Behave Differently?

Authors: Mariateresa Torchia, Helene Cristini, Hannele Kauppinen

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Leadership plays a vital role in organizations. Leaders provide directions and facilitate the processes that enable organizations to achieve their goals and objectives. However, while productivity and financial objectives are often given the greatest emphasis, leaders also have the responsibility for instituting standards of ethical conduct and moral values that guide the behavior of employees. Leaders’ behaviors such as support, empowerment and a high-quality relationship with their employees might not only prevent stress, but also improve employees’ stress coping meanwhile contributing to their affective well-being. Stemming from Girard’s Mimetic Theory, this study aims at understanding how leaders can foster well-being in organizations. To do so, we explore which is the role leaders play in conflict management, resentment management and negative emotions dissipation. Furthermore, we examine whether and to what extent religiosity impacts the way in which leaders operate in relation to employees’ well-being. Indeed, given that organizational values are crucial to ethical behavior and firms’ values may be steeled by a deep sense of spirituality and religious identification, there is a need to take a closer look at the role religion and spirituality play in influencing the way leaders impact employees’ well-being. Thus, religion might work as an overarching logic that provides a set of principles guiding leaders’ everyday practices and relations with employees. We answer our research questions using a qualitative approach. We interviewed 27 Christian leaders (members of the Christian Entrepreneurs and Leaders Association – EDC, a non-profit organization created in 1926 including 3,000 French Christian Leaders & Entrepreneurs). Our results show that well-being can have a different meaning in relation to the type of companies, size, culture, country of analysis. Moreover the values and believes of leaders influence the way they see and foster well-being among employees. Furthermore, leaders can have both a positive or negative impact on well-being. Indeed on the one side, they could increase well-being in the company while on the other hand, they could be the source of resentment and conflicts among employees. Finally, we observed that Christian leaders possess characteristics that are sometimes missing in leaders (humility, inability to compare with others, attempt to be coherent with their values and beliefs, interest in the common good instead of the personal interest, having tougher dilemmas, collectively undertaking the firm). Moreover the Christian leader believes that the common good should come before personal interest. In other words, to them, not only short –termed profit shouldn’t guide strategical decisions but also leaders should feel responsible for their employees’ well-being. Last but not least, the study is not an apologia of Christian, yet it discusses the implications of these values through the light of Girard’s mimetic theory for both theory and practice.

Keywords: Christian leaders, employees well-being, leadership, mimetic theory

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2328 Egalitarianism and Social Stratification: An Overview of the Caste System among the Southern Muslims of Sri Lanka

Authors: Mohamed Faslan

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This paper describes how caste-based differentiation functions among the Southern Muslims of Sri Lanka despite Islamic egalitarian principles. Such differences are not promoted by religious teachings, mosques, or the various Islamic religious denominations. Instead, it underpins a hereditary, hierarchical stratification in social structure. Since Islam is against social stratification and promotes egalitarianism, what are the persuasive social structures that organize the existing caste system among Southern Muslims? To answer this puzzle, this paper discusses and analyses the caste system under these five subsections: ancestry; marriage; geography; mosque ownership or trustees; and occupation. The study of caste in Sri Lanka is generally compartmentalized into separate Sinhala and Tamil systems. Most caste studies have focused on the characteristics, upward mobility, or discrimination of specific castes in relation to other castes within ethnic systems. As an operational definition, in this paper, by “southern” or the south of Sri Lanka, I refer to the Kalutara, Galle and Matara Districts. This research was conducted in these three districts, and the respondents were selected purposively. Community history interviews were used as a tool for collecting information, and grounded theory used for analysis. Caste stratification among the Southern Muslims of Sri Lanka is directly connected to whether they are descended from Arab or South Indian ancestors. Arab ancestors are considered upper caste and South Indian ancestors are considered lower caste. Endogamy is the most serious driving factor keeping caste system functioning among Muslims while the other factors—geography, mosques, and occupations—work as supporting factors.

Keywords: caste, social stratification, Sri Lanka Muslims, endogamy

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2327 Digitization and Economic Growth in Africa: The Role of Financial Sector Development

Authors: Abdul Ganiyu Iddrisu, Bei Chen

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Digitization is the process of transforming analog material into digital form, especially for storage and use in a computer. Significant development of information and communication technology (ICT) over the past years has encouraged many researchers to investigate its contribution to promoting economic growth and reducing poverty. Yet the compelling empirical evidence on the effects of digitization on economic growth remains weak, particularly in Africa. This is because extant studies that explicitly evaluate digitization and economic growth nexus are mostly reports and desk reviews. This points out an empirical knowledge gap in the literature. Hypothetically, digitization influences financial sector development which in turn influences economic growth. Digitization has changed the financial sector and its operating environment. Obstacles to access to financing, for instance, physical distance, minimum balance requirements, and low-income flows, among others can be circumvented. Savings have increased, micro-savers have opened bank accounts, and banks are now able to price short-term loans. This has the potential to develop the financial sector. However, empirical evidence on the digitization-financial development nexus is dearth. On the other hand, a number of studies maintained that financial sector development greatly influences growth of economies. We, therefore, argue that financial sector development is one of the transmission mechanisms through which digitization affects economic growth. Employing macro-country-level data from African countries and using fixed effects, random effects and Hausman-Taylor estimation approaches, this paper contributes to the literature by analysing economic growth in Africa, focusing on the role of digitization and financial sector development. First, we assess how digitization influences financial sector development in Africa. From an economic policy perspective, it is important to identify digitization determinants of financial sector development so that action can be taken to reduce the economic shocks associated with financial sector distortions. This nexus is rarely examined empirically in the literature. Secondly, we examine the effect of domestic credit to the private sector and stock market capitalization as a percentage of GDP as used to proxy for financial sector development on economic growth. Digitization is represented by the volume of digital/ICT equipment imported and GDP growth is used to proxy economic growth. Finally, we examine the effect of digitization on economic growth in the light of financial sector development. The following key results were found; first, digitalization propels financial sector development in Africa. Second, financial sector development enhances economic growth. Finally, contrary to our expectation, the results also indicate that digitalization conditioned on financial sector development tends to reduce economic growth in Africa. However, results of the net effects suggest that digitalization, overall, improve economic growth in Africa. We, therefore, conclude that, digitalization in Africa does not only develop the financial sector but unconditionally contributes the growth of the continent’s economies.

Keywords: digitalization, financial sector development, Africa, economic growth

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2326 Valorisation of Waste Chicken Feathers: Electrospun Antibacterial Nanoparticles-Embedded Keratin Composite Nanofibers

Authors: Lebogang L. R. Mphahlele, Bruce B. Sithole

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Chicken meat is the highest consumed meat in south Africa, with a per capita consumption of >33 kg yearly. Hence, South Africa produces over 250 million kg of waste chicken feathers each year, the majority of which is landfilled or incinerated. The discarded feathers have caused environmental pollution and natural protein resource waste. Therefore, the valorisation of waste chicken feathers is measured as a more environmentally friendly and cost-effective treatment. Feather contains 91% protein, the main component being beta-keratin, a fibrous and insoluble structural protein extensively cross linked by disulfide bonds. Keratin is usually converted it into nanofibers via electrospinning for a variety of applications. keratin nanofiber composites have many potential biomedical applications for their attractive features, such as high surface-to-volume ratio and very high porosity. The application of nanofibers in the biomedical wound dressing requires antimicrobial properties for materials. One approach is incorporating inorganic nanoparticles, among which silver nanoparticles played an important alternative antibacterial agent and have been studied against many types of microbes. The objective of this study is to combine synthetic polymer, chicken feather keratin, and antibacterial nanoparticles to develop novel electrospun antibacterial nanofibrous composites for possible wound dressing application. Furthermore, this study will converting a two-dimensional electrospun nanofiber membrane to three-dimensional fiber networks that resemble the structure of the extracellular matrix (ECM)

Keywords: chicken feather keratin, nanofibers, nanoparticles, nanocomposites, wound dressing

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2325 Digital Platform for Psychological Assessment Supported by Sensors and Efficiency Algorithms

Authors: Francisco M. Silva

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Technology is evolving, creating an impact on our everyday lives and the telehealth industry. Telehealth encapsulates the provision of healthcare services and information via a technological approach. There are several benefits of using web-based methods to provide healthcare help. Nonetheless, few health and psychological help approaches combine this method with wearable sensors. This paper aims to create an online platform for users to receive self-care help and information using wearable sensors. In addition, researchers developing a similar project obtain a solid foundation as a reference. This study provides descriptions and analyses of the software and hardware architecture. Exhibits and explains a heart rate dynamic and efficient algorithm that continuously calculates the desired sensors' values. Presents diagrams that illustrate the website deployment process and the webserver means of handling the sensors' data. The goal is to create a working project using Arduino compatible hardware. Heart rate sensors send their data values to an online platform. A microcontroller board uses an algorithm to calculate the sensor heart rate values and outputs it to a web server. The platform visualizes the sensor's data, summarizes it in a report, and creates alerts for the user. Results showed a solid project structure and communication from the hardware and software. The web server displays the conveyed heart rate sensor's data on the online platform, presenting observations and evaluations.

Keywords: Arduino, heart rate BPM, microcontroller board, telehealth, wearable sensors, web-based healthcare

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2324 Study of the Physical Aging of Polyvinyl Chloride (PVC)

Authors: Mohamed Ouazene

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The insulating properties of the polymers are widely used in electrical engineering for the production of insulators and various supports, as well as for the insulation of electric cables for medium and high voltage, etc. These polymeric materials have significant advantages both technically and economically. However, although the insulation with polymeric materials has advantages, there are also certain disadvantages such as the influence of the heat which can have a detrimental effect on these materials. Polyvinyl chloride (PVC) is one of the polymers used in a plasticized state in the cable insulation to medium and high voltage. The studied material is polyvinyl chloride (PVC 4000 M) from the Algerian national oil company whose formula is: Industrial PVC 4000 M is in the form of white powder. The test sample is a pastille of 1 mm thick and 1 cm in diameter. The consequences of increasing the temperature of a polymer are modifications; some of them are reversible and others irreversible [1]. The reversible changes do not affect the chemical composition of the polymer, or its structure. They are characterized by transitions and relaxations. The glass transition temperature is an important feature of a polymer. Physical aging of PVC is to maintain the material for a longer or shorter time to its glass transition temperature. The aim of this paper is to study this phenomenon by the method of thermally stimulated depolarization currents. Relaxations within the polymer have been recorded in the form of current peaks. We have found that the intensity decreases for more residence time in the polymer along its glass transition temperature. Furthermore, it is inferred from this work that the phenomenon of physical aging can have important consequences on the properties of the polymer. It leads to a more compact rearrangement of the material and a reconstruction or reinforcement of structural connections.

Keywords: depolarization currents, glass transition temperature, physical aging, polyvinyl chloride (PVC)

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2323 Exploring Polar Syntactic Effects of Verbal Extensions in Basà Language

Authors: Imoh Philip

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This work investigates four verbal extensions; two in each set resulting in two opposite effects of the valency of verbs in Basà language. Basà language is an indigenous language spoken in Kogi, Nasarawa, Benue, Niger states and all the Federal Capital Territory (FCT) councils. Crozier & Blench (1992) and Blench & Williamson (1988) classify Basà as belonging to Proto–Kru, under the sub-phylum Western –Kru. It studies the effects of such morphosyntactic operations in Basà language with special focus on ‘reflexives’ ‘reciprocals’ versus ‘causativization’ and ‘applicativization’ both sets are characterized by polar syntactic processes of either decreasing or increasing the verb’s valency by one argument vis-à-vis the basic number of arguments, but by the similar morphological processes. In addition to my native intuitions as a native speaker of Basà language, data elicited for this work include discourse observation, staged and elicited spoken data from fluent native speakers. The paper argues that affixes attached to the verb root, result in either deriving an intransitive verb from a transitive one or a transitive verb from a bi/ditransitive verb and equally increase the verb’s valence deriving either a bitransitive verb from a transitive verb or a transitive verb from a intransitive one. Where the operation increases the verb’s valency, it triggers a transformation of arguments in the derived structure. In this case, the applied arguments displace the inherent ones. This investigation can stimulate further study on other transformations that are either syntactic or morphosyntactic in Basà and can also be replicated in other African and non-African languages.

Keywords: verbal extension, valency, reflexive, reciprocal, causativization, applicativization, Basà

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2322 Synthesis and Analytical Characterisation of Polymer-Silica Nanoparticles Composite for the Protection and Preservation of Stone Monuments

Authors: Sayed M. Ahmed, Sawsan S. Darwish, Nagib A. Elmarzugi, Mohammad A. Al-Dosari, Mahmoud A. Adam, Nadia A. Al-Mouallimi

Abstract:

Historical stone surfaces and architectural heritage may undergo unwanted changes due to the exposure to many physical and chemical deterioration factors, the innovative properties of the nano - materials can have advantageous application in the restoration and conservation of the cultural heritage with relation to the tailoring of new products for protection and consolidation of stone. The current work evaluates the effectiveness of inorganic compatible treatments; based on nanosized particles of silica (SiO2) dispersed in silicon based product, commonly used as a water-repellent/ consolidation for the construction materials affected by different kinds of decay. The nanocomposites obtained by dispersing the silica nanoparticles in polymeric matrices SILRES® BS OH 100 (solventless mixtures of ethyl silicates), in order to obtain a new nanocomposite, with hydrophobic and consolidation properties, to improve the physical and mechanical properties of the stone material. The nanocomposites obtained and pure SILRES® BS OH 100 were applied by brush Experimental stone blocks. The efficacy of the treatments has been evaluated after consolidation and artificial Thermal aging, through capillary water absorption measurements, Ultraviolet-light exposure to evaluate photo-induced and the hydrophobic effects of the treated surface, Scanning electron microscopy (SEM) examination is performed to evaluate penetration depth, re-aggregating effects of the deposited phase and the surface morphology before and after artificialaging. Sterio microscopy investigation is performed to evaluate the resistant to the effects of the erosion, acids and salts. Improving of stone mechanical properties were evaluated by compressive strength tests, colorimetric measurements were used to evaluate the optical appearance. All the results get together with the apparent effect that, silica/polymer nanocomposite is efficient material for the consolidation of artistic and architectural sandstone monuments, completely compatible, enhanced the durability of sandstone toward thermal and UV aging. In addition, the obtained nanocomposite improved the stone mechanical properties and the resistant to the effects of the erosion, acids and salts compared to the samples treated with pure SILRES® BS OH 100 without silica nanoparticles.

Keywords: colorimetric measurements, compressive strength, nanocomposites, porous stone consolidation, silica nanoparticles, sandstone

Procedia PDF Downloads 248
2321 Improving Biodegradation Behavior of Fabricated WE43 Magnesium Alloy by High-Temperature Oxidation

Authors: Jinge Liu, Shuyuan Min, Bingchuan Liu, Bangzhao Yin, Bo Peng, Peng Wen, Yun Tian

Abstract:

WE43 magnesium alloy can be additively manufactured via laser powder bed fusion (LPBF) for biodegradable applications, but the as-built WE43 exhibits an excessively rapid corrosion rate. High-temperature oxidation (HTO) was performed on the as-built WE43 to improve its biodegradation behavior. A sandwich structure including an oxide layer at the surface, a transition layer in the middle, and the matrix was generated influenced by the oxidation reaction and diffusion of RE atoms when heated at 525 ℃for 8 hours. The oxide layer consisted of Y₂O₃ and Nd₂O₃ oxides with a thickness of 2-3 μm. The transition layer is composed of α-Mg and Y₂O₃ with a thickness of 60-70 μm, while Mg24RE5 could be observed except α-Mg and Y₂O₃. The oxide layer and transition layer appeared to have an effective passivation effect. The as-built WE43 lost 40% weight after the in vitro immersion test for three days and finally broke into debris after seven days of immersion. The high-temperature oxidation samples kept the structural integrity and lost only 6.88 % weight after 28-day immersion. The corrosion rate of HTO samples was significantly controlled, which improved the biocompatibility of the as-built WE43 at the same time. The samples after HTO had better osteogenic capability according to ALP activity. Moreover, as built WE43 performed unqualified in cell adhesion and hemolytic test due to its excessively rapid corrosion rate. While as for HTO samples, cells adhered well, and the hemolysis ratio was only 1.59%.

Keywords: laser powder bed fusion, biodegradable metal, high temperature oxidation, biodegradation behavior, WE43

Procedia PDF Downloads 101
2320 Understanding Patterns of Hard Coral Demographics in Kenyan Reefs to Inform Restoration

Authors: Swaleh Aboud, Mishal Gudka, David Obura

Abstract:

Background: Coral reefs are becoming increasingly vulnerable due to several threats ranging from climate change to overfishing. This has resulted in increased management and conservation efforts to protect reefs from degradation and facilitate recovery. Recruitmentof new individuals are isimportant in the recovery process and critical for the persistence of coral reef ecosystems. Local coral community structure can be influenced by successful recruit settlement, survival, and growth Understanding coral recruitment patterns can help quantify reef resilience and connectivity, establish baselines and track changes and evaluate the effectiveness of reef restoration and conservation efforts. This study will examine the abundance and spatial pattern of coral recruits and how this relates to adult community structure, including the distribution of thermal resistance and sensitive genera and their distribution in different management regimes. Methods: Coral recruit and demography surveys were conducted from 2020 to 2022, covering 35 sites in 19coral reef locations along the Kenyan coast. These included marine parks, reserves, community conservation areas (CMAs), and open access areas from the north (Marereni) to the south (Kisite) coast of Kenya and across different reef habitats. The data was collected through the underwater visual census (UVC) technique. We counted adult corals (>10 cm diameter)of23 selected genera using belt transects (25 by 1 m) and sampling of 1 m2 quadrat (at an interval of 5m) for all coloniesless than 10 cm diameter. The benthic cover was collected using photo quadrats. The surveys were only done during the northeast monsoon season. The data wereanalyzed using the R program to see the distribution patterns and the Kruskal Wallis test to see whether there was a significant difference. Spearman correlation was also applied to assess the relationship between the distribution of coral genera in recruits and adults. Results: A total of 44 different coral genera were recorded for recruits, ranging from 3at Marereni to 30at Watamu Marine Reserve. Recruit densities ranged from 1.2±1.5recruit m-2 (mean±SD) at Likoni to 10.3± 8.4 recruit m-2 at Kisite Marine Park. The overall densityof recruitssignificantly differed between reef locations, with Kisite Marine Park and Reserve and Likonihaving significantly large differences from all the other locations, while Vuma, Watamu, Malindi, and Kilifi had significantly lower differences from all the other locations. The recruit generadensity along the Kenya coastwas divided into two clusters, one of which only included sites inKisite Marine Park. Adult colonies were dominated by Porites massive, Acropora, Platygyra, and Favites, whereas recruits were dominated by Porites branching, Porites massive, Galaxea, and Acropora. However, correlation analysis revealed a statistically significant positive correlation (r=0.81, p<0.05) between recruit and adult coral densities across the 23 coral genera. Marereni, which had the lowest densityof recruits, has only thermallyresistant coral genera, while Kisite Marine Park, with the highest recruit densities, has over 90% thermal sensitive coral genera. A weak positive correlation was found between recruit density and coralline algae, dead standing corals, and turf algae, whereas a weak negative correlation was found between recruit density and bare substrate and macroalgae. Between management regimes, marine reserves were found to have more recruits than no-take zones (marine parks and CMAs) and open access areas, although the difference was not significant. Conclusion: There was a statistically significant difference in the density of recruits between different reef locations along the Kenyan coast. Although the dominating genera of adults and recruits were different, there was a strong positive correlation between their coral communities, which could indicate self-recruitment processes or consistent distance seedings (of the same recruit genera). Sites such as Kisite Marine Park, with high recruit densities but dominated by thermally sensitive genera, will, on the other hand, be adversely affected by future thermal stress. This could imply that reducing the threats to coral reefs such as overfishingcould allow for their natural regeneration and recovery.

Keywords: coral recruits, coral adult size-class, cora demography, resilience

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2319 Limiting Freedom of Expression to Fight Radicalization: The 'Silencing' of Terrorists Does Not Always Allow Rights to 'Speak Loudly'

Authors: Arianna Vedaschi

Abstract:

This paper addresses the relationship between freedom of expression, national security and radicalization. Is it still possible to talk about a balance between the first two elements? Or, due to the intrusion of the third, is it more appropriate to consider freedom of expression as “permanently disfigured” by securitarian concerns? In this study, both the legislative and the judicial level are taken into account and the comparative method is employed in order to provide the reader with a complete framework of relevant issues and a workable set of solutions. The analysis moves from the finding according to which the tension between free speech and national security has become a major issue in democratic countries, whose very essence is continuously endangered by the ever-changing and multi-faceted threat of international terrorism. In particular, a change in terrorist groups’ recruiting pattern, attracting more and more people by way of a cutting-edge communicative strategy, often employing sophisticated technology as a radicalization tool, has called on law-makers to modify their approach to dangerous speech. While traditional constitutional and criminal law used to punish speech only if it explicitly and directly incited the commission of a criminal action (“cause-effect” model), so-called glorification offences – punishing mere ideological support for terrorism, often on the web – are becoming commonplace in the comparative scenario. Although this is direct, and even somehow understandable, consequence of the impending terrorist menace, this research shows many problematic issues connected to such a preventive approach. First, from a predominantly theoretical point of view, this trend negatively impacts on the already blurred line between permissible and prohibited speech. Second, from a pragmatic point of view, such legislative tools are not always suitable to keep up with ongoing developments of both terrorist groups and their use of technology. In other words, there is a risk that such measures become outdated even before their application. Indeed, it seems hard to still talk about a proper balance: what was previously clearly perceived as a balancing of values (freedom of speech v. public security) has turned, in many cases, into a hierarchy with security at its apex. In light of these findings, this paper concludes that such a complex issue would perhaps be better dealt with through a combination of policies: not only criminalizing ‘terrorist speech,’ which should be relegated to a last resort tool, but acting at an even earlier stage, i.e., trying to prevent dangerous speech itself. This might be done by promoting social cohesion and the inclusion of minorities, so as to reduce the probability of people considering terrorist groups as a “viable option” to deal with the lack of identification within their social contexts.

Keywords: radicalization, free speech, international terrorism, national security

Procedia PDF Downloads 195
2318 Obesity and Cancer: Current Scientific Evidence and Policy Implications

Authors: Martin Wiseman, Rachel Thompson, Panagiota Mitrou, Kate Allen

Abstract:

Since 1997 World Cancer Research Fund (WCRF) International and the American Institute for Cancer Research (AICR) have been at the forefront of synthesising and interpreting the accumulated scientific literature on the link between diet, nutrition, physical activity and cancer, and deriving evidence-based Cancer Prevention Recommendations. The 2007 WCRF/AICR 2nd Expert Report was a landmark in the analysis of evidence linking diet, body weight and physical activity to cancer and led to the establishment of the Continuous Update Project (CUP). In 2018, as part of the CUP, WCRF/AICR will publish a new synthesis of the current evidence and update the Cancer Prevention Recommendations. This will ensure that everyone - from policymakers and health professionals to members of the public - has access to the most up-to-date information on how to reduce the risk of developing cancer. Overweight and obesity play a significant role in cancer risk, and rates of both are increasing in many parts of the world. This session will give an overview of new evidence relating obesity to cancer since the 2007 report. For example, since the 2007 Report, the number of cancers for which obesity is judged to be a contributory cause has increased from seven to eleven. The session will also shed light on the well-established mechanisms underpinning obesity and cancer links. Additionally, the session will provide an overview of diet and physical activity related factors that promote positive energy imbalance, leading to overweight and obesity. Finally, the session will highlight how policy can be used to address overweight and obesity at a population level, using WCRF International’s NOURISHING Framework. NOURISHING formalises a comprehensive package of policies to promote healthy diets and reduce obesity and non-communicable diseases; it is a tool for policymakers to identify where action is needed and assess if an approach is sufficiently comprehensive. The framework brings together ten policy areas across three domains: food environment, food system, and behaviour change communication. The framework is accompanied by a regularly updated database providing an extensive overview of implemented government policy actions from around the world. In conclusion, the session will provide an overview of obesity and cancer, highlighting the links seen in the epidemiology and exploring the mechanisms underpinning these, as well as the influences that help determine overweight and obesity. Finally, the session will illustrate policy approaches that can be taken to reduce overweight and obesity worldwide.

Keywords: overweight, obesity, nutrition, cancer, mechanisms, policy

Procedia PDF Downloads 153
2317 Adjustment of the Whole-Body Center of Mass during Trunk-Flexed Walking across Uneven Ground

Authors: Soran Aminiaghdam, Christian Rode, Reinhard Blickhan, Astrid Zech

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Despite considerable studies on the impact of imposed trunk posture on human walking, less is known about such locomotion while negotiating changes in ground level. The aim of this study was to investigate the behavior of the VBCOM in response to a two-fold expected perturbation, namely alterations in body posture and in ground level. To this end, the kinematic data and ground reaction forces of twelve able participants were collected. We analyzed the vertical position of the body center of mass (VBCOM) from the ground determined by the body segmental analysis method relative to the laboratory coordinate system at touchdown and toe-off instants during walking across uneven ground — characterized by perturbation contact (a 10-cm visible drop) and pre- and post-perturbation contacts — in comparison to unperturbed level contact while maintaining three postures (regular erect, ~30° and ~50° of trunk flexion from the vertical). The VBCOM was normalized to the distance between the greater trochanter marker and the lateral malleoli marker at the instant of TD. Moreover, we calculated the backward rotation during step-down as the difference of the maximum of the trunk angle in the pre-perturbation contact and the minimal trunk angle in the perturbation contact. Two-way repeated measures ANOVAs revealed contact-specific effects of posture on the VBCOM at touchdown (F = 5.96, p = 0.00). As indicated by the analysis of simple main effects, during unperturbed level and pre-perturbation contacts, no between-posture differences for the VBCOM at touchdown were found. In the perturbation contact, trunk-flexed gaits showed a significant increase of VBCOM as compared to the pre-perturbation contact. In the post-perturbation contact, the VBCOM demonstrated a significant decrease in all gait postures relative to the preceding corresponding contacts with no between-posture differences. Main effects of posture revealed that the VBCOM at toe-off significantly decreased in trunk-flexed gaits relative to the regular erect gait. For the main effect of contact, the VBCOM at toe-off demonstrated changes across perturbation and post-perturbation contacts as compared to the unperturbed level contact. Furthermore, participants exhibited a backward trunk rotation during step-down possibly to control the angular momentum of their whole body. A more pronounced backward trunk rotation (2- to 3-fold compared with level contacts) in trunk-flexed walking contributed to the observed elevated VBCOM during the step-down which may have facilitated drop negotiation. These results may shed light on the interaction between posture and locomotion in able gait, and specifically on the behavior of the body center of mass during perturbed locomotion.

Keywords: center of mass, perturbation, posture, uneven ground, walking

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2316 Impact of Reverse Technology Transfer on Innovation Capabilities: An Econometric Analysis for Mexican Transnational Corporations

Authors: Lissette Alejandra Lara, Mario Gomez, Jose Carlos Rodriguez

Abstract:

ransnational corporations (TNCs) as units in which it is possible technology and knowledge transfer across borders and the potential for generating innovation and contributing in economic development both in home and host countries have been widely acknowledged in the foreign direct investment (FDI) literature. Particularly, the accelerated expansion of emerging countries TNCs in the last decades has guided an uprising research stream that measure the presence of reverse technology transfer, defined as the extent to which emerging countries’ TNCs use outward FDI in a host country through certain mechanisms to absorb and transfer knowledge thus improving its technological capabilities in the home country. The objective of this paper is to test empirically the presence of reverse technology transfer and its impact on the innovation capabilities in Mexican transnational corporations (MXTNCs) as a part of the emerging countries TNCs that have successfully entered to industrialized markets. Using a panel dataset of 22 MXTNCs over the period 1994-2015, the results of the econometric model demonstrate that the amount of Mexican outward FDI and the research and development (R&D) expenditure in host developed countries had a positive impact on the innovation capabilities at the firm and industry level. There is also evidence that management of acquired brands and the organizational structure of Mexican subsidiaries improved these capabilities. Implications for internationalization strategies of emerging countries corporations and future research guidelines are discussed.

Keywords: emerging countries, foreign direct investment, innovation capabilities, Mexican transnational corporations, reverse technology transfer

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2315 Artificial Intelligence-Aided Extended Kalman Filter for Magnetometer-Based Orbit Determination

Authors: Gilberto Goracci, Fabio Curti

Abstract:

This work presents a robust, light, and inexpensive algorithm to perform autonomous orbit determination using onboard magnetometer data in real-time. Magnetometers are low-cost and reliable sensors typically available on a spacecraft for attitude determination purposes, thus representing an interesting choice to perform real-time orbit determination without the need to add additional sensors to the spacecraft itself. Magnetic field measurements can be exploited by Extended/Unscented Kalman Filters (EKF/UKF) for orbit determination purposes to make up for GPS outages, yielding errors of a few kilometers and tens of meters per second in the position and velocity of a spacecraft, respectively. While this level of accuracy shows that Kalman filtering represents a solid baseline for autonomous orbit determination, it is not enough to provide a reliable state estimation in the absence of GPS signals. This work combines the solidity and reliability of the EKF with the versatility of a Recurrent Neural Network (RNN) architecture to further increase the precision of the state estimation. Deep learning models, in fact, can grasp nonlinear relations between the inputs, in this case, the magnetometer data and the EKF state estimations, and the targets, namely the true position, and velocity of the spacecraft. The model has been pre-trained on Sun-Synchronous orbits (SSO) up to 2126 kilometers of altitude with different initial conditions and levels of noise to cover a wide range of possible real-case scenarios. The orbits have been propagated considering J2-level dynamics, and the geomagnetic field has been modeled using the International Geomagnetic Reference Field (IGRF) coefficients up to the 13th order. The training of the module can be completed offline using the expected orbit of the spacecraft to heavily reduce the onboard computational burden. Once the spacecraft is launched, the model can use the GPS signal, if available, to fine-tune the parameters on the actual orbit onboard in real-time and work autonomously during GPS outages. In this way, the provided module shows versatility, as it can be applied to any mission operating in SSO, but at the same time, the training is completed and eventually fine-tuned, on the specific orbit, increasing performances and reliability. The results provided by this study show an increase of one order of magnitude in the precision of state estimate with respect to the use of the EKF alone. Tests on simulated and real data will be shown.

Keywords: artificial intelligence, extended Kalman filter, orbit determination, magnetic field

Procedia PDF Downloads 99
2314 Conservativeness of Functional Proteins in Bovine Milk by Pulsed Electric Field Technology

Authors: Sulhee Lee, Geon Kim, Young-Seo Park

Abstract:

Unlike the traditional milk sterilization methods (LTLT, HTST, or UHT), pulsed electric field (PEF) technology is a non-thermal pasteurization process. This technology minimizes energy required for heat treatment in food processing, changes in sensory properties, and physical losses. In this study, structural changes of bovine milk proteins, the amount of immunoproteins such as IgG, and their storability by PEF treatment were examined. When the changes of protein content in PEF-treated milk were examined using HPLC, the amounts of α-casein and β-lactoglobulin were reduced over 40% each, whereas those of κ-casein and β-casein did not change. The amount of α-casein in HTST milk was reduced to 50%. When PEF was applied to milk at the energy level of 250 kJ, the amounts of IgG, IgA, β-lactoglobulin (β-LG), lactoferrin, and α-lactalbumin (α-LA) decreased by 43, 41, 35, 63, and 45%, respectively. When milk was sterilized by LTLT process followed by PEF process at the level of 150 kJ, the concentrations of IgG, IgA, β-LG, lactoferrin, and α-LA were 56.6, 10.6, 554, 2.8 and 660.1 μg/mL, respectively. When the bovine milk was sterilized by LTLT process followed by PEF process at the energy level of 180 kJ, storability of immunoproteins of milk was the highest and the concentrations of IgG, IgA, and β-LG decreased by 79.5, 6.5, and 134.5 μg/mL, respectively, when compared with the initial concentrations of those proteins. When bovine milk was stored at 4℃ after sterilization through HTST sterilizer followed by PEF process at the energy level of 200 kJ, the amount of lactoferrin decreased 7.3% after 36 days of storage, whereas that of lactoferrin of raw milk decreased 16.4%. Our results showed that PEF treatment did not change the protein structure nor induce protein denaturation in milk significantly when compared with LTLT or HTST sterilization. Also, LTLT or HTST process in combination with PEF were more effective than LTLT only or HTST only process in the conservation of immunoproteins in bovine milk.

Keywords: pulsed electric field, bovine milk, immunoproteins, sterilization

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2313 Antioxidant Activity of Probiotic Lactic Acid Bacteria and Their Application in Fermented Milk Products

Authors: Vitheejongjaroen P., Jaisin Y., Pachekrepapol U., Taweechotipatr M.

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Lactic acid bacteria (LAB) are the most common type of microorganisms that had been used as probiotics also known for many beneficial health effects. The antioxidant activity of LAB is associated with numerous health-protective effects. This research aimed to investigate the antioxidant activity of lactic acid bacteria isolated from Thai sour pork sausage for their application in fermented milk products. Antioxidant activity determined by DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging assay showed that the isolate FN33-7, as 1 of 8 isolated exhibited scavenging activity in intact cell 5-7%, and supernatant 13-16%, intracellular cell free extract 42-48% respectively. This isolate was identified using 16S ribosomal DNA sequence analysis as Lactobacillus plantarum. The effect of milk fermented with L. plantarum FN33-7 on microbial count, pH and syneresis was assessed during refrigerated storage period of 28 days. The strain showed increased viability, pH level decreased, while syneresis increased. These results are similar to dairy products fermented with commercial starter cultures. Additionally, microstructure analysis of fermented milk by fluorescent microscopy showed that curd structure appeared to be dense and less porous in this fermented milk than commercial yogurt. The results of this study indicated that L. plantarum FN33-7 was a good probiotic candidate to be used in cultured milk products to reduce the risk of diseases caused by oxidative stress.

Keywords: Lactobacillus plantarum, probiotics, free radical, antioxidant, oxidative stress, fermented milk products

Procedia PDF Downloads 127
2312 Work Related Musculoskeletal Disorder: A Case Study of Office Computer Users in Nigerian Content Development and Monitoring Board, Yenagoa, Bayelsa State, Nigeria

Authors: Tamadu Perry Egedegu

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Rapid growth in the use of electronic data has affected both the employee and work place. Our experience shows that jobs that have multiple risk factors have a greater likelihood of causing Work Related Musculoskeletal Disorder (WRMSDs), depending on the duration, frequency and/or magnitude of exposure to each. The study investigated musculoskeletal disorder among office workers. Thus, it is important that ergonomic risk factors be considered in light of their combined effect in causing or contributing to WRMSDs. Fast technological growth in the use of electronic system; have affected both workers and the work environment. Awkward posture and long hours in front of these visual display terminals can result in work-related musculoskeletal disorders (WRMSD). The study shall contribute to the awareness creation on the causes and consequences of WRMSDs due to lack of ergonomics training. The study was conducted using an observational cross-sectional design. A sample of 109 respondents was drawn from the target population through purposive sampling method. The sources of data were both primary and secondary. Primary data were collected through questionnaires and secondary data were sourced from journals, textbooks, and internet materials. Questionnaires were the main instrument for data collection and were designed in a YES or NO format according to the study objectives. Content validity approval was used to ensure that the variables were adequately covered. The reliability of the instrument was done through test-retest method, yielding a reliability index at 0.84. The data collected from the field were analyzed with a descriptive statistics of chart, percentage and mean. The study found that the most affected body regions were the upper back, followed by the lower back, neck, wrist, shoulder and eyes, while the least affected body parts were the knee calf and the ankle. Furthermore, the prevalence of work-related 'musculoskeletal' malfunctioning was linked with long working hours (6 - 8 hrs.) per day, lack of back support on their seats, glare on the monitor, inadequate regular break, repetitive motion of the upper limbs, and wrist when using the computer. Finally, based on these findings some recommendations were made to reduce the prevalent of WRMSDs among office workers.

Keywords: work related musculoskeletal disorder, Nigeria, office computer users, ergonomic risk factor

Procedia PDF Downloads 235
2311 Encapsulation of Probiotic Bacteria in Complex Coacervates

Authors: L. A. Bosnea, T. Moschakis, C. Biliaderis

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Two probiotic strains of Lactobacillus paracasei subsp. paracasei (E6) and Lactobacillus paraplantarum (B1), isolated from traditional Greek dairy products, were microencapsulated by complex coacervation using whey protein isolate (WPI, 3% w/v) and gum arabic (GA, 3% w/v) solutions mixed at different polymer ratio (1:1, 2:1 and 4:1). The effect of total biopolymer concentration on cell viability was assessed using WPI and GA solutions of 1, 3 and 6% w/v at a constant ratio of 2:1. Also, several parameters were examined for optimization of the microcapsule formation, such as inoculum concentration and the effect of ionic strength. The viability of the bacterial cells during heat treatment and under simulated gut conditions was also evaluated. Among the different WPI/GA weight ratios tested (1:1, 2:1, and 4:1), the highest survival rate was observed for the coacervate structures made with the ratio of 2:1. The protection efficiency at low pH values is influenced by both concentration and the ratio of the added biopolymers. Moreover, the inoculum concentration seems to affect the efficiency of microcapsules to entrap the bacterial cells since an optimum level was noted at less than 8 log cfu/ml. Generally, entrapment of lactobacilli in the complex coacervate structure enhanced the viability of the microorganisms when exposed to a low pH environment (pH 2.0). Both encapsulated strains retained high viability in simulated gastric juice (>73%), especially in comparison with non-encapsulated (free) cells (<19%). The encapsulated lactobacilli also exhibited enhanced viability after 10–30 min of heat treatment (65oC) as well as at different NaCl concentrations (pH 4.0). Overall, the results of this study suggest that complex coacervation with WPI/GA has a potential to deliver live probiotics in low pH food systems and fermented dairy products; the complexes can dissolve at pH 7.0 (gut environment), releasing the microbial cells.

Keywords: probiotic, complex coacervation, whey, encapsulation

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2310 Luminescent Dye-Doped Polymer Nanofibers Produced by Electrospinning Technique

Authors: Monica Enculescu, A. Evanghelidis, I. Enculescu

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Among the numerous methods for obtaining polymer nanofibers, the electrospinning technique distinguishes itself due to the more growing interest induced by its proved utility leading to developing and improving of the method and the appearance of novel materials. In particular, production of polymeric nanofibers in which different dopants are introduced was intensively studied in the last years because of the increased interest for the obtaining of functional electrospun nanofibers. Electrospinning is a facile method of obtaining polymer nanofibers with diameters from tens of nanometers to micrometrical sizes that are cheap, flexible, scalable, functional and biocompatible. Besides the multiple applications in medicine, polymeric nanofibers obtained by electrospinning permit manipulation of light at nanometric dimensions when doped with organic dyes or different nanoparticles. It is a simple technique that uses an electrical field to draw fine polymer nanofibers from solutions and does not require complicated devices or high temperatures. Different morphologies of the electrospun nanofibers can be obtained for the same polymeric host when different parameters of the electrospinning process are used. Consequently, we can obtain tuneable optical properties of the electrospun nanofibers (e.g. changing the wavelength of the emission peak) by varying the parameters of the fabrication method. We focus on obtaining doped polymer nanofibers with enhanced optical properties using the electrospinning technique. The aim of the paper is to produce dye-doped polymer nanofibers’ mats incorporating uniformly dispersed dyes. Transmission and fluorescence of the fibers will be evaluated by spectroscopy methods. The morphological properties of the electrospun dye-doped polymer fibers will be evaluated using scanning electron microscopy (SEM). We will tailor the luminescent properties of the material by doping the polymer (polyvinylpyrrolidone or polymethylmetacrilate) with different dyes (coumarins, rhodamines and sulforhodamines). The tailoring will be made taking into consideration the possibility of changing the luminescent properties of electrospun polymeric nanofibers that are doped with different dyes by using different parameters for the electrospinning technique (electric voltage, distance between electrodes, flow rate of the solution, etc.). Furthermore, we can evaluated the influence of the concentration of the dyes on the emissive properties of dye-doped polymer nanofibers using different concentrations. The advantages offered by the electrospinning technique when producing polymeric fibers are given by the simplicity of the method, the tunability of the morphology allowed by the possibility of controlling all the process parameters (temperature, viscosity of polymeric solution, applied voltage, distance between electrodes, etc.), and by the absence of necessity of using harsh and supplementary chemicals such as the ones used in the traditional nanofabrication techniques. Acknowledgments: The authors acknowledge the financial support received through IFA CEA Project No. C5-08/2016.

Keywords: electrospinning, luminescence, polymer nanofibers, scanning electron microscopy

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2309 The Hallmarks of War Propaganda: The Case of Russia-Ukraine Conflict

Authors: Veronika Solopova, Oana-Iuliana Popescu, Tim Landgraf, Christoph Benzmüller

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Beginning in 2014, slowly building geopolitical tensions in Eastern Europe led to a full-blown conflict between the Russian Federation and Ukraine that generated an unprecedented amount of news articles and data from social media data, reflecting the opposing ideologies and narratives as a background and the essence of the ongoing war. These polarized informational campaigns have led to countless mutual accusations of misinformation and fake news, shaping an atmosphere of confusion and mistrust for many readers all over the world. In this study, we analyzed scraped news articles from Ukrainian, Russian, Romanian and English-speaking news outlets, on the eve of 24th of February 2022, compared to day five of the conflict (28th of February), to see how the media influenced and mirrored the changes in public opinion. We also contrast the sources opposing and supporting the stands of the Russian government in Ukrainian, Russian and Romanian media spaces. In a data-driven way, we describe how the narratives are spread throughout Eastern and Central Europe. We present predictive linguistic features surrounding war propaganda. Our results indicate that there are strong similarities in terms of rhetoric strategies in the pro-Kremlin media in both Ukraine and Russia, which, while being relatively neutral according to surface structure, use aggressive vocabulary. This suggests that automatic propaganda identification systems have to be tailored for each new case, as they have to rely on situationally specific words. Both Ukrainian and Russian outlets lean towards strongly opinionated news, pointing towards the use of war propaganda in order to achieve strategic goals.

Keywords: linguistic, news, propaganda, Russia, ukraine

Procedia PDF Downloads 114