Search results for: check ball
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1043

Search results for: check ball

383 Automated Video Surveillance System for Detection of Suspicious Activities during Academic Offline Examination

Authors: G. Sandhya Devi, G. Suvarna Kumar, S. Chandini

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This research work aims to develop a system that will analyze and identify students who indulge in malpractices/suspicious activities during the course of an academic offline examination. Automated Video Surveillance provides an optimal solution which helps in monitoring the students and identifying the malpractice event immediately. This work is organized into three modules. The first module deals with performing an impersonation check using a PCA-based face recognition method which is done by cross checking his profile with the database. The presence or absence of the student is even determined in this module by implementing an image registration technique wherein a grid is formed by considering all the images registered using the frontal camera at the determined positions. Second, detecting such facial malpractices in which a student gets involved in conversation with another, trying to obtain unauthorized information etc., based on the threshold range evaluated by considering his/her mouth state whether open or closed. The third module deals with identification of unauthorized material or gadgets used in the examination hall by training the positive samples of the object through various stages. Here, a top view camera feed is analyzed to detect the suspicious activities. The system automatically alerts the administration when any suspicious activities are identified, thereby reducing the error rate caused due to manual monitoring. This work is an improvement over our previous work published in identifying suspicious activities done by examinees in an offline examination.

Keywords: impersonation, image registration, incrimination, object detection, threshold evaluation

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382 Psychological Well-Being and Human Rights of Teenage Mothers Attending One Secondary School in the Eastern Cape, South Africa

Authors: Veliswa Nonfundo Hoho, Jabulani Gilford Kheswa

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This paper reports on teenage motherhood and its adverse outcomes on the academic performance, emotional well-being and sexual relationships that adolescent females encounter. Drawing from Ryff’s six dimensions of psychological well-being and Bronfenbrenner’s ecological model which underpinned this study, teenage motherhood has been found to link with multiple factors such as poverty, negative self-esteem, substance abuse, cohabitation, intimate partner violence and ill-health. Furthermore, research indicates that in schools where educators fail to perform their duties as loco-parentis to motivate adolescent females learners who are mothers, absenteeism, poor academic performance and learned helplessness, are likely. The aim of this research was two-fold, namely; (i) to determine the impact of teenage motherhood on the psychological well-being of the teenage mothers and (ii) to investigate the policies which protect the human rights of teenage mothers attending secondary schools. In a qualitative study conducted in one secondary school, Fort Beaufort, Eastern Cape, South Africa, fifteen Xhosa-speaking teenage mothers, aged 15-18 years old, were interviewed. The sample was recruited by means of snow-ball sampling. To safeguard the human dignity of the respondents, informed consent, confidentiality, anonymity and privacy of the respondents were assured. For trustworthiness, this research ensured that credibility, neutrality, and transferability, are met. Following an axial and open coding of responses, five themes were identified; Health issues of teenage mothers, lack of support, violation of human rights, impaired sense of purpose in life and intimate partner-violence. From these findings, it is clear that teenage mothers lack resilience and are susceptible to contract sexually transmitted infections and HIV/AIDS because they are submissive and hopeless. Furthermore, owing to stigma that the teenage mothers' experience from family members, they resort to alcohol and drug abuse, and feel demotivated to bond with their babies. In conclusion, the recommendations are that the Health and Social Development departments collaborate to empower the psychological well-being of teenage mothers. Furthermore, school policies on discrimination should be enacted and consistently implemented.

Keywords: depression, discrimination, self-esteem, teenage mothers

Procedia PDF Downloads 253
381 The Analysis of Emergency Shutdown Valves Torque Data in Terms of Its Use as a Health Indicator for System Prognostics

Authors: Ewa M. Laskowska, Jorn Vatn

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Industry 4.0 focuses on digital optimization of industrial processes. The idea is to use extracted data in order to build a decision support model enabling use of those data for real time decision making. In terms of predictive maintenance, the desired decision support tool would be a model enabling prognostics of system's health based on the current condition of considered equipment. Within area of system prognostics and health management, a commonly used health indicator is Remaining Useful Lifetime (RUL) of a system. Because the RUL is a random variable, it has to be estimated based on available health indicators. Health indicators can be of different types and come from different sources. They can be process variables, equipment performance variables, data related to number of experienced failures, etc. The aim of this study is the analysis of performance variables of emergency shutdown valves (ESV) used in oil and gas industry. ESV is inspected periodically, and at each inspection torque and time of valve operation are registered. The data will be analyzed by means of machine learning or statistical analysis. The purpose is to investigate whether the available data could be used as a health indicator for a prognostic purpose. The second objective is to examine what is the most efficient way to incorporate the data into predictive model. The idea is to check whether the data can be applied in form of explanatory variables in Markov process or whether other stochastic processes would be a more convenient to build an RUL model based on the information coming from registered data.

Keywords: emergency shutdown valves, health indicator, prognostics, remaining useful lifetime, RUL

Procedia PDF Downloads 69
380 Spirometric Reference Values in 236,606 Healthy, Non-Smoking Chinese Aged 4–90 Years

Authors: Jiashu Shen

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Objectives: Spirometry is a basic reference for health evaluation which is widely used in clinical. Previous reference of spirometry is not applicable because of drastic changes of social and natural circumstance in China. A new reference values for the spirometry of the Chinese population is extremely needed. Method: Spirometric reference value was established using the statistical modeling method Generalized Additive Models for Location, Scale and Shape for forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), FEV1/FVC, and maximal mid-expiratory flow (MMEF). Results: Data from 236,606 healthy non-smokers aged 4–90 years was collected from the MJ Health Check database. Spirometry equations for FEV1, FVC, MMEF, and FEV1/FVC were established, including the predicted values and lower limits of normal (LLNs) by sex. The predictive equations that were developed for the spirometric results elaborated the relationship between spirometry and age, and they eliminated the effects of height as a variable. Most previous predictive equations for Chinese spirometry were significantly overestimated (to be exact, with mean differences of 22.21% in FEV1 and 31.39% in FVC for males, along with differences of 26.93% in FEV1 and 35.76% in FVC for females) or underestimated (with mean differences of -5.81% in MMEF and -14.56% in FEV1/FVC for males, along with a difference of -14.54% in FEV1/FVC for females) the results of lung function measurements as found in this study. Through cross-validation, our equations were established as having good fit, and the means of the measured value and the estimated value were compared, with good results. Conclusions: Our study updates the spirometric reference equations for Chinese people of all ages and provides comprehensive values for both physical examination and clinical diagnosis.

Keywords: Chinese, GAMLSS model, reference values, spirometry

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379 Artificial Intelligence Based Abnormality Detection System and Real Valuᵀᴹ Product Design

Authors: Junbeom Lee, Jaehyuck Cho, Wookyeong Jeong, Jonghan Won, Jungmin Hwang, Youngseok Song, Taikyeong Jeong

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This paper investigates and analyzes meta-learning technologies that use multiple-cameras to monitor and check abnormal behavior in people in real-time in the area of healthcare fields. Advances in artificial intelligence and computer vision technologies have confirmed that cameras can be useful for individual health monitoring and abnormal behavior detection. Through this, it is possible to establish a system that can respond early by automatically detecting abnormal behavior of the elderly, such as patients and the elderly. In this paper, we use a technique called meta-learning to analyze image data collected from cameras and develop a commercial product to determine abnormal behavior. Meta-learning applies machine learning algorithms to help systems learn and adapt quickly to new real data. Through this, the accuracy and reliability of the abnormal behavior discrimination system can be improved. In addition, this study proposes a meta-learning-based abnormal behavior detection system that includes steps such as data collection and preprocessing, feature extraction and selection, and classification model development. Various healthcare scenarios and experiments analyze the performance of the proposed system and demonstrate excellence compared to other existing methods. Through this study, we present the possibility that camera-based meta-learning technology can be useful for monitoring and testing abnormal behavior in the healthcare area.

Keywords: artificial intelligence, abnormal behavior, early detection, health monitoring

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378 Root Cause Analysis of Surveillance Quality in Tanjung Priok Port to Prevent Epidemic Potential Disease as a Form of Bioterrorism Threat

Authors: Dina A. Amu, Fifi N. Afifah, Catur Rosidati, Tirton Nefianto

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Indonesia was shaken up by the avian influenza cases that had caused the country suffered losses of millions of dollars. The avian influenza case had even been suspected as a bioterrorism attack since it was an uncommon case in epidemiology. Furthermore, this avian influenza virus is a high pathogenic one and Indonesia has the highest case of fatality rate in the world. Bioterrorism threats or epidemic potential disease outbreaks currently does not exist in Tanjung Priok port yet. However, the surveillance system enhancement on epidemic potential diseases should be taken as a prevention, especially because Indonesia is currently facing the ASEAN Economic Society (AES). Therefore, this research evaluates the health surveillance system which is organized by Control, Quarantine and Surveillance Department, Health Office of Tanjung Priok Port. This study uses qualitative-evaluative method which utilizes Urgency Seriousness Growth (USG) method to determine priority issues and Root Cause analysis to determine the cause of prior problem. The result of this research shows that the implementation of epidemic potential disease surveillance in Tanjung Priok port has not done in the best possible way. It is because the lack of time allocation and the succinctness of the check list of ship's environmental health inspection. Therefore, Health Ministry of Indonesia should recruit more employees at the health office of Tanjung Priok port, hold a simulation of ship's inspection and simplify the list for ship's environmental health inspection.

Keywords: surveillance, epidemic potential disease, port health, bioterrorism

Procedia PDF Downloads 339
377 Muslim Husbands’ Participation in Women’s Health and Illness: A Descriptive Exploratory Study Applied to Muslim Women in Indonesia

Authors: Restuning Widiasih, Katherine Nelson, Joan Skinner

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Muslim husbands have significant roles in the family including their roles in women’s health and illness. However, studies that explore Muslim husbands’ participation in women’s health is limited. The objective of this study was to uncover Muslim husbands’ participation in women’ health and illness including cancer prevention and screening. A descriptive exploratory approach was used involving 20 Muslim women from urban and rural areas of West Java Province, Indonesia. Muslim women shared experience related to their husbands support and activities in women’s health and illness. The data from the interviews were analyzed using the Comparative Analysis for Interview (CAI). Women perceived that husbands fully supported their health by providing opportunities for activities, and reminding them about healthy food, their workloads, and family planning. Husbands actively involved when women faced health issues including sharing knowledge and experience, discussing any health problems, advising for medical check-ups, and accompanying them for treatments. The analysis also found that husbands were less active and offered less advice regarding prevention and early detection of cancer. This study highlights the significant involvement of Muslim husbands in women’s health and illness, yet a lack of support from husbands related to screening and cancer prevention. This condition could be a burden for Muslim women to participate in health programs related to cancer prevention and early detection. Health education programs to improve Muslim husbands’ understanding of women’s health is needed.

Keywords: descriptive exploratory study, Muslim husbands, Muslim women, women's health and illness

Procedia PDF Downloads 487
376 Evaluation of Raw Diatomaceous Earth and Plant Powders in the Control of Callosobruchus subinnotatus (Pic.) on Stored Bambara Groundnut (Vigna subterranea (L.) (Verdc.) Seeds

Authors: Ibrahim Nasiru Dole, Audu Abdullahi, Dike Michiel Chidozie, Lawal Mansur

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Bambara groundnut is an important grain legume and the seeds in storage suffer infestation by Callosobruchus subinnotatus. Laboratory study was conducted to evaluate the efficacy of raw diatomaceous earth (RDE) and plant powders (Jatropha curcas (L.), Eucalyptus camaldulensis (Dehnh.) and Melia azedarach (L.) against C. subinnotatus infesting stored bambara groundnut seeds. Rearing of the insects and the experiments were conducted in Agricultural Biology Laboratory of the Usmanu Danfodiyo University, Sokoto - Nigeria under ambient conditions (29-33oC and a relative humidity of 44-56%). Four treatments at three levels: RDE at 0.5, 1.0 and 1.5 g while plant powders at 0.5, 1.0 and 2.0 g, standard/check (2.0 g of Actellic dust), and a control. These were separately admixed with 100 g of sterilized seeds in glass jars. Each jar was later infested with thirty, 1-2-days old C. subinnotatus of mixed sexes. Adult mortality was assessed 24, 48, 72 and 96 hours, F1 and F2 progenies, seed damage, weight loss and viability were also assessed after 90 days. Eighty-nine (89%) percent adult mortality was recorded in the highest dose of RDE after 96 hours of exposure. These treatments significantly (P < 0.05) suppressed F1 and F2 progenies emergence in relation to the control. The control suffered significantly (P < 0.05) higher seed damage (51.0 %) and weight loss (40.8%) thereby recording lower seed germination. Therefore, RDE and plant powders could be used against C. subinnotatus on stored bambara groundnut seeds.

Keywords: bambara, callosobruchus subinnotatus, plant powders, raw diatomaceous earth,

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375 Growth and Development of Autorickshaws in Kolkata Municipal Corporation Area: Enigma to Planners

Authors: Lopamudra Bakshi Basu

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Transport is one of the most important characteristic features of Indian cities. The physical and societal requirements determine the selection of a particular transport system along with the uniqueness of road networks. Kolkata has a mixed traffic of which Paratransit system plays a crucial role. It is an indispensable transport system in Kolkata mainly because of its size and service flexibility which has led to a unique network character. The paratransit system, mainly the autorickshaws, is the most favoured mode of transport in the city. Its fast movement and comfortability make it a vital transport system of the city. Since the inception of the autorickshaws in Kolkata in 1981, this mode has gained popularity and presently serves nearly 80 to 90 percent of the total passenger trips. This employment generating mode of transport has increased its number rapidly affecting the city’s traffic. Minimal check on their growth by the authority has led to traffic snarls along many streets of Kolkata. Indiscipline behavior, violation of traffic rules and rash driving make situations even worse. The rise in the number and increasing popularity of the autorickshaws make it an interesting study area. Autorickshaws as a paratransit mode play its role as a leader or a follower. However, it is informal in its planning and operations, which makes it a problem area for the city. The entire research work deals with the growth and expansion of the number of vehicles and the routes within the city. The development of transport system has been interesting in the city, which has been studied. The growth of the paratransit modes in the city has been rapid. The network pattern of the paratransit mode within Kolkata has been analysed.

Keywords: growth, informal, network characteristics, paratransit, service flexibility

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374 Person-Led Organizations Nurture Bullying Behavior: A Qualitative Study

Authors: Shreya Mishra, Manosi Chaudhuri, Ajoy K. Dey

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Workplace bullying is a social phenomenon which has proved to be hazardous not only for employees’ well-being but also organizations. Despite being prevalent across geographical boundaries, Indian organizations have failed to acknowledge its vices. This paper aims to understand targets’ perception on what makes bullying nurture in organizations. The paper suggests that person-led Indian work settings give birth to bullying behavior as it lacks professional acumen and systems. An analysis of 13 in-depth interviews of employees from the organized sector suggests that organizations, where decision making lies with single individual, may be a hub of hostile behavior due to the culture which promotes ‘yesmanship’, ‘authoritarianism’ and/or blind belief of leaders on certain set of employees. The study used constructivist grounded theory approach, and the data was analyzed using R Based Qualitative Data Analysis (RQDA) software. Respondents reported that bullying behavior is taken lightly by the management with 'just ignore it' attitude. According to the respondents, the behavior prolong as the perpetrator have a direct approach to the top authority. The study concludes that person-led organizations may create a family-like environment which is favored by employees; however, authoritative leaders are unable to gain the trust of employees. Also, employees who are close to the leader may either be a perpetrator or a target of bullying. It is recommended that leaders in such organizations need to acknowledge the presence of bullying which affects an employees’ commitment towards their job and/or organization. They need to have an assertive check on individuals who hide behind ‘yesman’ attitude. This may help employees feel safe in such work settings.

Keywords: constructivist grounded theory, person-led organization, RQDA, workplace bullying

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373 Determining the Efficacy of Phenol, Sodium Hypochlorite and Ethanol for Inactivation of Carbapenem-Resistant Strain of Acinetobacter baumannii

Authors: Deepika Biswas

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Acinetobacter baumannii, a hospital-acquired pathogen, causes nosocomial infections including pneumonia, urinary tract infection, and secondary meningitis. Carbapenem is most effective antibiotics against it. Its increased resistance to carbapenems has been a rising global concern. Antibiotics such as carbapenem are unable to use on hospital setups to eradicate A. baumannii, hence different concentrations of disinfectants including phenol; sodium hypochlorite and ethanol are increasingly being used. The objective of the present study is to find an effective concentration of above disinfectants against carbapenem-resistant strain RS307 of A. baumannii. Growth kinetics of RS307 has been determined using UV-Vis spectrophotometer in the presence and absence of disinfectants in triplicate and its standard deviation has also been calculated which make the results more reliable. Differential growth curves were plotted, which showed the effective concentration among all the concentrations of phenol, sodium hypochlorite and ethanol. On disc diffusion assay, antimicrobial effect was observed by comparing all the concentrations of disinfectants to check its synergy with imipenem, most effective carbapenem. All the results collectively revealed that 0.5% phenol, 0.5% sodium hypochlorite, and 70% ethanol could preferably be used as disinfectant for hospital setup against the carbapenem-resistant strain of A. baumannii. SDS PAGE analysis showed differential expression in the protein profile of A. baumannii after treatment. The present study highlighted that few disinfectants even in low concentration had shown better antimicrobial activity hence may be recommended for regular use in the hospitals, which will be cost effective and less harmful.

Keywords: Acenatobacter bomunii, phenol, sodium hypoclirite, ethanol, carbapenem resistance, disinfectant

Procedia PDF Downloads 237
372 Unveiling the Impact of Ultra High Vacuum Annealing Levels on Physico-Chemical Properties of Bulk ZnSe Semiconductor

Authors: Kheira Hamaida, Mohamed Salah Halati

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In this current paper, our aim work is to link as possible the obtained simulation results and the other experimental ones, just focusing on the electronic and optical properties of ZnSe. The predictive spectra of the total and partial densities of states using the Full Potential Linearized/Augmented Plane Wave method with the newly Tran-Blaha (TB) modified Becke-Johnson (mBJ) exchange-correlation potential (EXC). So the upper valence energy (UVE) levels contain the relative contribution of Se-(4p and 3d) states with considerable contribution from the electrons of Zn-2s orbital. The dielectric function of w-ZnSe, with its two parts, appears with a noticeable anisotropy character. The microscopic origins of the electronic states that are responsible for the observed peaks in the spectrum are determined through the decomposition of the spectrum to the individual contributions of the electronic transitions between the pairs of bands, where Vi is an occupied state in the valence band, and Ci is an unoccupied state in the conduction band. X-PES (X Ray-Photo Electron Spectroscopy) is an important technique used to probe the homogeneity, stoichiometry, and purity state of the title compound. In order to check the electron transitions derived from simulations and the others from Reflected Electron Energy Loss Spectroscopy (REELS) technique which was of great sensitivity, is used to determine the interband electronic transitions. In the optical window (Eg), all the electron energy states created were also determined through the specific gaussian deconvolution of the photoluminescence spectrum (PLS) that probed under a room temperature (RT).

Keywords: spectroscopy, WIEN2K, IIB-VIA semiconductors, dielectric function

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371 Alpha-To-Omega Phase Transition in Bulk Nanostructured Ti and (α+β) Ti Alloys

Authors: Askar Kilmametov, Julia Ivanisenko, Boris Straumal, Horst Hahn

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The high-pressure α- to ω-phase transition was discovered in elemental Ti and Zr fifty years ago using static high pressure and then observed to appear between 2 and 12 GPa at room temperature, depending on the experimental technique, the pressure environment, and the sample purity. The fact that ω-phase is retained in a metastable state in ambient condition after the removal of the pressure has been used to check the changes in magnetic and superconductive behavior, electron band structure and mechanical properties. However, the fundamental knowledge on a combination of both mechanical treatment and high applied pressure treatments for ω-phase formation in Ti alloys is currently lacking and has to be studied in relation to improved mechanical properties of bulk nanostructured states. In the present study, nanostructured (α+β) Ti alloys containing β-stabilizing elements such as Co, Fe, Cr, Nb were performed by severe plastic deformation, namely high pressure torsion (HPT) technique. HPT-induced α- to ω-phase transformation was revealed in dependence on applied pressure and shear strains by means of X-ray diffraction, transmission electron microscopy, and differential scanning calorimetry. The transformation kinetics was compared with the kinetics of pressure-induced transition. Orientation relationship between α-, β- and ω-phases was taken into consideration and analyzed according to theoretical calculation proposed earlier. The influence of initial state before HPT appeared to be considerable for subsequent α- to ω-phase transition. Thermal stability of the HPT-induced ω-phase was discussed as well in the frame of mechanical behavior of Ti and Ti-based alloys produced by shear deformation under high applied pressure.

Keywords: bulk nanostructured materials, high pressure phase transitions, severe plastic deformation, titanium alloys

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370 Application of Seasonal Autoregressive Integrated Moving Average Model for Forecasting Monthly Flows in Waterval River, South Africa

Authors: Kassahun Birhanu Tadesse, Megersa Olumana Dinka

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Reliable future river flow information is basic for planning and management of any river systems. For data scarce river system having only a river flow records like the Waterval River, a univariate time series models are appropriate for river flow forecasting. In this study, a univariate Seasonal Autoregressive Integrated Moving Average (SARIMA) model was applied for forecasting Waterval River flow using GRETL statistical software. Mean monthly river flows from 1960 to 2016 were used for modeling. Different unit root tests and Mann-Kendall trend analysis were performed to test the stationarity of the observed flow time series. The time series was differenced to remove the seasonality. Using the correlogram of seasonally differenced time series, different SARIMA models were identified, their parameters were estimated, and diagnostic check-up of model forecasts was performed using white noise and heteroscedasticity tests. Finally, based on minimum Akaike Information (AIc) and Hannan-Quinn (HQc) criteria, SARIMA (3, 0, 2) x (3, 1, 3)12 was selected as the best model for Waterval River flow forecasting. Therefore, this model can be used to generate future river information for water resources development and management in Waterval River system. SARIMA model can also be used for forecasting other similar univariate time series with seasonality characteristics.

Keywords: heteroscedasticity, stationarity test, trend analysis, validation, white noise

Procedia PDF Downloads 183
369 Investigating the Effect of the Shape of the Side Supports of the Gates of the Gotvand Reservoir Dam (from the Peak Overflows) on the Narrowing Coefficients

Authors: M. Abbasi

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A spillway structure is used to pass excess water and floods from upstream or upstream to downstream or tributary. The spillway is considered one of the most key members of the dam, and the failure of many dams is attributed to the inefficiency of their spillway. Weirs should be selected as strong, reliable and high-performance structures, and weirs should be ready for use in all conditions and able to drain the flood so that we do not witness many casualties and financial losses when a flood occurs. The purpose of this study is to simulate the flow pattern passing over the peak spillway in order to optimize and adjust the height of the spillway walls. In this research, the effect of the shape of the side wings on the flow pattern over the peak spillways of the Gotvand reservoir dam was simulated and modelled using Flow3D software. In this research, side wings with rounded walls with six different approach angles were used. In addition, the different value of H/Hd was used to check the effect of the tank head. The results showed that with the constant H/Hd ratio and the increase of the approach angle of the side wing, the flow depth first decreases and then increases. These changes were the opposite regarding the depth average speed of the flow and the depth average concentration of the air entering the flow. At the same time, with the constant angle of approach of the side wing and with the increase of H/Hd ratio, the flow depth increases. In general, a correct understanding of the operation of overflows and a correct design can significantly reduce construction costs and solve flooding problems.

Keywords: effect of the shape, gotvand reservoir dam, narrowing coefficients, supports of the gates

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368 Mitigating Denial of Service Attacks in Information Centric Networking

Authors: Bander Alzahrani

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Information-centric networking (ICN) using architectures such as Publish-Subscribe Internet Routing Paradigm (PSIRP) is one of the promising candidates for a future Internet, has recently been under the spotlight by the research community to investigate the possibility of redesigning the current Internet architecture to solve many issues such as routing scalability, security, and quality of services issues.. The Bloom filter-based forwarding is a source-routing approach that is used in the PSIRP architecture. This mechanism is vulnerable to brute force attacks which may lead to denial-of-service (DoS) attacks. In this work, we present a new forwarding approach that keeps the advantages of Bloom filter-based forwarding while mitigates attacks on the forwarding mechanism. In practice, we introduce a special type of forwarding nodes called Edge-FW to be placed at the edge of the network. The role of these node is to add an extra security layer by validating and inspecting packets at the edge of the network against brute-force attacks and check whether the packet contains a legitimate forwarding identifier (FId) or not. We leverage Certificateless Aggregate Signature (CLAS) scheme with a small size of 64-bit which is used to sign the FId. Hence, this signature becomes bound to a specific FId. Therefore, malicious nodes that inject packets with random FIds will be easily detected and dropped at the Edge-FW node when the signature verification fails. Our preliminary security analysis suggests that with the proposed approach, the forwarding plane is able to resist attacks such as DoS with very high probability.

Keywords: bloom filter, certificateless aggregate signature, denial-of-service, information centric network

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367 Enabling Community Participation for Social Innovation in the Energy Sector

Authors: Budiman Ibnu

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This study investigates about enabling conditions to facilitate social innovation in the energy sector. This is important to support the energy transition in Indonesia. This research provides appropriate project direction, including research (and action) gaps for the energy actors in Indonesia. The actors are allowed to work further with the result of this study to stimulate the energy transition in Indonesia. This report uses systemic change framework which recognizes four drivers of systemic change in a region: 1. transforming political ecologies; 2. configuring green economies; 3. building of adaptive communities; 4. social innovation. These drivers are interconnected, and this report particularly focuses on how social innovation can be supported by other drivers. This study used methods of interview and literature review as the main sources for data collection in this report. There were interviews with eight experts in the related topic which come from different countries which have experienced social innovation in the energy sector. Afterwards, this research reviewed related journal papers from last five years, to check the latest development within the topic, to support the interview result. The result found that the enabling condition can focus on one of the drivers of systemic change, which is building communities by increasing their participation, through several integrated actions. This can be implemented in two types of citizen energy initiatives which are energy cooperatives and sustainable consumption initiatives. This implementation requires study about its related policy and governance support, in order to create complete enabling conditions to facilitate social innovation in the energy transition.

Keywords: enabling condition, social innovation, citizen initiatives, community participation

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366 Error Detection and Correction for Onboard Satellite Computers Using Hamming Code

Authors: Rafsan Al Mamun, Md. Motaharul Islam, Rabana Tajrin, Nabiha Noor, Shafinaz Qader

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In an attempt to enrich the lives of billions of people by providing proper information, security and a way of communicating with others, the need for efficient and improved satellites is constantly growing. Thus, there is an increasing demand for better error detection and correction (EDAC) schemes, which are capable of protecting the data onboard the satellites. The paper is aimed towards detecting and correcting such errors using a special algorithm called the Hamming Code, which uses the concept of parity and parity bits to prevent single-bit errors onboard a satellite in Low Earth Orbit. This paper focuses on the study of Low Earth Orbit satellites and the process of generating the Hamming Code matrix to be used for EDAC using computer programs. The most effective version of Hamming Code generated was the Hamming (16, 11, 4) version using MATLAB, and the paper compares this particular scheme with other EDAC mechanisms, including other versions of Hamming Codes and Cyclic Redundancy Check (CRC), and the limitations of this scheme. This particular version of the Hamming Code guarantees single-bit error corrections as well as double-bit error detections. Furthermore, this version of Hamming Code has proved to be fast with a checking time of 5.669 nanoseconds, that has a relatively higher code rate and lower bit overhead compared to the other versions and can detect a greater percentage of errors per length of code than other EDAC schemes with similar capabilities. In conclusion, with the proper implementation of the system, it is quite possible to ensure a relatively uncorrupted satellite storage system.

Keywords: bit-flips, Hamming code, low earth orbit, parity bits, satellite, single error upset

Procedia PDF Downloads 106
365 Tribological Behavior of Hybrid Nanolubricants for Internal Combustion Engines

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

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

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

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364 The Role of Phycoremediation in the Sustainable Management of Aquatic Pollution

Authors: Raymond Ezenweani, Jeffrey Ogbebor

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The menace of aquatic pollution has become increasingly of great concern and the effects of this pollution as a result of anthropogenic activities cannot be over emphasized. Phycoremediation is the application of algal remediation technology in the removal of harmful products from the environment. Harmful products also known as pollutants are usually introduced into the environment through variety of processes such as industrial discharge, agricultural runoff, flooding, and acid rain. This work has to do with the capability of algae in the efficient removal of different pollutants, ranging from hydrocarbons, eutrophication, agricultural chemicals and wastes, heavy metals, foul smell from septic tanks or dumps through different processes such as bioconversion, biosorption, bioabsorption and biodecomposition. Algae are capable of bioconversion of environmentally persistent compounds to degradable compounds and also capable of putting harmful bacteria growth into check in waste water remediation. Numerous algal organisms such as Nannochloropsis spp, Chlorella spp, Tetraselmis spp, Shpaerocystics spp, cyanobacteria and different macroalgae have been tested by different researchers in laboratory scale and shown to have 100% efficiency in environmental remediation. Algae as a result of their photosynthetic capacity are also efficient in air cleansing and management of global warming by sequestering carbon iv oxide in air and converting it into organic carbon, thereby making food available for the other organisms in the higher trophic level of the aquatic food chain. Algae play major role in the sustenance of the aquatic ecosystem by their virtue of being photosynthetic. They are the primary producers and their role in environmental sustainability is remarkable.

Keywords: Algae , Pollutant, ., Phycoremediation, Aquatic, Sustainability

Procedia PDF Downloads 93
363 Convertible Lease, Risky Debt and Financial Structure with Growth Option

Authors: Ons Triki, Fathi Abid

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The basic objective of this paper is twofold. It resides in designing a model for a contingent convertible lease contract that can ensure the financial stability of a company and recover the losses of the parties to the lease in the event of default. It also aims to compare the convertible lease contract on inefficiencies resulting from the debt-overhang problem and asset substitution with other financing policies. From this perspective, this paper highlights the interaction between investments and financing policies in a dynamic model with existing assets and a growth option where the investment cost is financed by a contingent convertible lease and equity. We explore the impact of the contingent convertible lease on the capital structure. We also check the reliability and effectiveness of the use of the convertible lease contract as a means of financing. Findings show that the rental convertible contract with a sufficiently high conversion ratio has less severe inefficiencies arising from risk-shifting and debt overhang than those entailed by risky debt and pure-equity financing. The problem of underinvestment pointed out by Mauer and Ott (2000) and the problem of overinvestment mentioned by Hackbarth and Mauer (2012) may be reduced under contingent convertible lease financing. Our findings predict that the firm value under contingent convertible lease financing increases globally with asset volatility instead of decreasing with business risk. The study reveals that convertible leasing contracts can stand for a reliable solution to ensure the lessee and quickly recover the counterparties of the lease upon default.

Keywords: contingent convertible lease, growth option, debt overhang, risk-shifting, capital structure

Procedia PDF Downloads 53
362 High Injury Prevalence in Adolescent Field Hockey Players: Implications for Future Practice

Authors: Pillay J. D., D. De Wit, J. F. Ducray

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Field hockey is a popular international sport which is played in more than 100 countries across the world. Due to the nature of hockey, players repeatedly perform a combination of forward flexion and rotational movements of the spine in order to strike the ball. These movements have been shown to increase the risk of pain and injury to the lumbar spine. The aim of this study was to determine the prevalence and incidence of low back pain (LBP) in male adolescent field hockey players and the characteristics of LBP in terms of location, chronicity, disability, and treatment sought, as well as its association with selected risk factors. A survey was conducted on 112 male adolescent field hockey players in the eThekwini Municipality of KwaZulu-Natal, South Africa. The questionnaire contained sections on the demographics of participants, general characteristics of participants, health and lifestyle characteristics, low back pain patterns, treatment of low back pain, and the level of disability associated with LBP. The data were statistically analysed using IBM SPSS version 25 with statistical significance set at p-value <0.05. Descriptive statistics such as mean and standard deviation were used to summarise responses to continuous variables as appropriate. Categorical variables were described using frequency tables. Associations between risk factors and low back pain were tested using Pearson’s chi-square test and t-tests as appropriate. A total of 68 questionnaires were completed for analysis (67% participation rate); the period prevalence of LBP was 63.2% (35.0%:beginning of the season, 32.4%:mid-season, 22.1%: end of season). Incidence was 38.2%. The most common location for LBP was the middle low back region (39.5%), and the most common duration of pain was a few hours (32.6%). Most participants (79.1%) did not classify their pain as a disability, and only 44.2% of participants received medical treatment for their LBP. An interesting finding was the association between hydration and LBP (p = 0.050), i.e., those individuals who did not hydrate frequently during matches and training were significantly more likely to experience LBP. The results of this study, although limited to a select group of adolescents, showed a higher prevalence of LBP than that of previous studies. More importantly, even though most participants did not experience LBP classified as a disability, LBP still had a large impact on participants, as nearly half of the participants consulted with a medical professional for treatment. Need for the application of further strategies in the prevention and management of LBP in field hockey, such as adequate warm-up and cool-down, stretching exercises, rest between sessions, etc., are recommended as simple strategies to reduce LBP prevalence.

Keywords: adolescents, field hockey players, incidence, low back pain, prevalence, risk factors

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361 Adding a Few Language-Level Constructs to Improve OOP Verifiability of Semantic Correctness

Authors: Lian Yang

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Object-oriented programming (OOP) is the dominant programming paradigm in today’s software industry and it has literally enabled average software developers to develop millions of commercial strength software applications in the era of INTERNET revolution over the past three decades. On the other hand, the lack of strict mathematical model and domain constraint features at the language level has long perplexed the computer science academia and OOP engineering community. This situation resulted in inconsistent system qualities and hard-to-understand designs in some OOP projects. The difficulties with regards to fix the current situation are also well known. Although the power of OOP lies in its unbridled flexibility and enormously rich data modeling capability, we argue that the ambiguity and the implicit facade surrounding the conceptual model of a class and an object should be eliminated as much as possible. We listed the five major usage of class and propose to separate them by proposing new language constructs. By using well-established theories of set and FSM, we propose to apply certain simple, generic, and yet effective constraints at OOP language level in an attempt to find a possible solution to the above-mentioned issues regarding OOP. The goal is to make OOP more theoretically sound as well as to aid programmers uncover warning signs of irregularities and domain-specific issues in applications early on the development stage and catch semantic mistakes at runtime, improving correctness verifiability of software programs. On the other hand, the aim of this paper is more practical than theoretical.

Keywords: new language constructs, set theory, FSM theory, user defined value type, function groups, membership qualification attribute (MQA), check-constraint (CC)

Procedia PDF Downloads 220
360 Incidence, Risk Factors and Impact of Major Adverse Events Following Paediatric Cardiac Surgery

Authors: Sandipika Gupta

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Objective: Due to admirably low 30-day mortality rates for paediatric cardiac surgery, it is now pertinent to turn towards more intermediate-length outcomes such as morbidities closely associated with these surgeries. One such morbidity, major adverse events (MAE) comprises a group of adverse outcomes associated with paediatric cardiac surgery (e.g. cardiac arrest, major haemorrhage). Methods: This is a retrospective study that analysed the incidence and impact of MAE which was the primary outcome in the UK population. The data was collected in 5 centres between October 2015 and June 2017, amassing 3090 surgical episodes. The incidence and risk factors for MAE, were assessed through descriptive statistical analyses and multivariate logistic regression. The secondary outcomes of life status at 6 months and the length of hospital stay were also evaluated to understand the impact of MAE on patients. Results: Out of 3090 episodes, 134 (4.3%) had a postoperative MAE. The majority of the episodes were in: neonates (47%, P<0.001), high-risk cardiac diagnosis groups (20.1%, P<0.001), episodes with longer 5mes on the bypass (72.4%, P<0.001) and urgent surgeries (57.9%, P<0.001). Episodes reporting MAE also reported longer lengths of stay in hospital (29 days vs 9 days, P<0.001). Furthermore, patients experiencing MAE were at a higher risk of mortality at the 6-month life status check (mortality rates: 29.2% vs 2%, P<0.001).Conclusions: Key risk factors were identified. An important negative impact of MAE was found for patients. The identified risk factors could be used to profile and flag at-risk patients. Monitoring of MAE rates and closer investigation into the care pathway before and after individual MAEs in children’s heart units may lead to a reduction in these terrible events.

Keywords:

Procedia PDF Downloads 208
359 Osteogenesis in Thermo-Sensitive Hydrogel Using Mesenchymal Stem Cell Derived from Human Turbinate

Authors: A. Reum Son, Jin Seon Kwon, Seung Hun Park, Hai Bang Lee, Moon Suk Kim

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These days, stem cell therapy is focused on for promising source of treatment in clinical human disease. As a supporter of stem cells, in situ-forming hydrogels with growth factors and cells appear to be a promising approach in tissue engineering. To examine osteogenic differentiation of hTMSCs which is one of mesenchymal stem cells in vivo in an injectable hydrogel, we use a methoxy polyethylene glycol-polycaprolactone blockcopolymer (MPEG-PCL) solution with osteogenic factors. We synthesized MPEG-PCL hydrogel and measured viscosity to check sol-gel transition. In order to demonstrate osteogenic ability of hTMSCs, we conducted in vitro osteogenesis experiment. Then, to confirm the cell cytotoxicity, we performed WST-1 with hTMSCs and MPEG-PCL. As the result of in vitro experiment, we implanted cell and hydrogel mixture into animal model and checked degree of osteogenesis with histological analysis and amount of expression genes. Through these experimental data, MPEG-PCL hydrogel has sol-gel transition in temperature change and is biocompatible with stem cells. In histological analysis and gene expression, hTMSCs are very good source of osteogenesis with hydrogel and will use it to tissue engineering as important treatment method. hTMSCs could be a good adult stem cell source for usability of isolation and high proliferation. When hTMSCs are used as cell therapy method with in situ-formed hydrogel, they may provide various benefits like a noninvasive alternative for bone tissue engineering applications.

Keywords: injectable hydrogel, stem cell, osteogenic differentiation, tissue engineering

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358 Endeavor to Develop Immunological and Hematological Early Diagnostic Marker to Check the Conversion of Asymptomatic to Symptomatic Visceral Leishmaniasis

Authors: Roshan Kamal Topno, Maneesh Kumar, Manas Ranjan Dikhit, Krishna Pandey, Major Madhukar, Vidhya Nand Rabidas, Vahab Ali, Ganesh Chandra Sahoo, Bhawana, Devendra Prasad Yadav, Rishikesh Kumar, Pradeep Das

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A diagnostic marker for asymptomatic subject becomes a crucial need for advocating early prophylactic majors to control protozoal infection. The main issue in epidemiological affected regions is the presence of an asymptomatic individual that might potentially convert to a symptomatic visceral leishmaniasis (VL). The epidemiological study has been conducted at highly VL endemic Moriyama village in Patna district, Bihar, India that covers total population of 1540 individuals. Here, 1104(74.02%) people had been randomly screened and only 46 (4.17%) asymptomatic individuals were found sero-positive by the rK39 test. After taking signed informed consent form, blood samples were collected from 46 asymptomatic subjects for further hematological and immunological tests. Total leukocyte count, hemoglobin (gm%), neutrophil, lymphocyte, platelet count and interleukin-10 (IL-10) had been included as diagnostic markers. Interestingly only 5 (10.86%) individuals showed their asymptomatic conversion into symptomatic VL patients during quarterly surveillance. In overall analysis only two markers are suggestive for disease conversion that is hemoglobin (gm%) and IL-10. In all the infected patients, both the mean decrease in hemoglobin and mean increase of IL-10 was 19.23% from its normal value. The results might suggest that hematological and immunological changes would become helpful for early diagnosis of asymptomatic to symptomatic VL conversion.

Keywords: asymptomatic, epidemiological, symptomatic visceral leishmaniasis, hemoglobin (gm%), interleukin-10, diagnosis

Procedia PDF Downloads 186
357 Porcelain Paste Processing by Robocasting 3D: Parameters Tuning

Authors: A. S. V. Carvalho, J. Luis, L. S. O. Pires, J. M. Oliveira

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Additive manufacturing technologies (AM) experienced a remarkable growth in the latest years due to the development and diffusion of a wide range of three-dimensional (3D) printing techniques. Nowadays we can find techniques available for non-industrial users, like fused filament fabrication, but techniques like 3D printing, polyjet, selective laser sintering and stereolithography are mainly spread in the industry. Robocasting (R3D) shows a great potential due to its ability to shape materials with a wide range of viscosity. Industrial porcelain compositions showing different rheological behaviour can be prepared and used as candidate materials to be processed by R3D. The use of this AM technique in industry is very residual. In this work, a specific porcelain composition with suitable rheological properties will be processed by R3D, and a systematic study of the printing parameters tuning will be shown. The porcelain composition was formulated based on an industrial spray dried porcelain powder. The powder particle size and morphology was analysed. The powders were mixed with water and an organic binder on a ball mill at 200 rpm/min for 24 hours. The batch viscosity was adjusted by the addition of an acid solution and mixed again. The paste density, viscosity, zeta potential, particle size distribution and pH were determined. In a R3D system, different speed and pressure settings were studied to access their impact on the fabrication of porcelain models. These models were dried at 80 °C, during 24 hours and sintered in air at 1350 °C for 2 hours. The stability of the models, its walls and surface quality were studied and their physical properties were accessed. The microstructure and layer adhesion were observed by SEM. The studied processing parameters have a high impact on the models quality. Moreover, they have a high impact on the stacking of the filaments. The adequate tuning of the parameters has a huge influence on the final properties of the porcelain models. This work contributes to a better assimilation of AM technologies in ceramic industry. Acknowledgments: The RoboCer3D project – project of additive rapid manufacturing through 3D printing ceramic material (POCI-01-0247-FEDER-003350) financed by Compete 2020, PT 2020, European Regional Development Fund – FEDER through the International and Competitive Operational Program (POCI) under the PT2020 partnership agreement.

Keywords: additive manufacturing, porcelain, robocasting, R3D

Procedia PDF Downloads 142
356 Investigations Of The Service Life Of Different Material Configurations At Solid-lubricated Rolling Bearings

Authors: Bernd Sauer, Michel Werner, Stefan Emrich, Michael Kopnarski, Oliver Koch

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Friction reduction is an important aspect in the context of sustainability and energy transition. Rolling bearings are therefore used in many applications in which components move relative to each other. Conventionally lubricated rolling bearings are used in a wide range of applications, but are not suitable under certain conditions. Conventional lubricants such as grease or oil cannot be used at very high or very low temperatures. In addition, these lubricants evaporate at very low ambient pressure, e.g. in a high vacuum environment, making the use of solid lubricated bearings unavoidable. With the use of solid-lubricated bearings, predicting the service life becomes more complex. While the end of the service life of bearings with conventional lubrication is mainly caused by the failure of the bearing components due to material fatigue, solid-lubricated bearings fail at the moment when the lubrication layer is worn and the rolling elements come into direct contact with the raceway during operation. In order to extend the service life of these bearings beyond the service life of the initial coating, the use of transfer lubrication is recommended, in which pockets or sacrificial cages are used in which the balls run and can thus absorb the lubricant, which is then available for lubrication in tribological contact. This contribution presents the results of wear and service life tests on solid-lubricated rolling bearings with sacrificial cage pockets. The cage of the bearing consists of a polyimide (PI) matrix with 15% molybdenum disulfide (MoS2) and serves as a lubrication depot alongside the silver-coated balls. The bearings are tested under high vacuum (pE < 10-2 Pa) at a temperature of 300 °C on a four-bearing test rig. First, investigations of the bearing system within the bearing service life are presented and the torque curve, the wear mass and surface analyses are discussed. With regard to wear, it can be seen that the bearing rings tend to increase in mass over the service life of the bearing, while the balls and the cage tend to lose mass. With regard to the elementary surface properties, the surfaces of the bearing rings and balls are examined in terms of the mass of the elements on them. Furthermore, service life investigations with different material pairings are presented, whereby the focus here is on the service life achieved in addition to the torque curve, wear development and surface analysis. It was shown that MoS2 in the cage leads to a longer service life, while a silver (Ag) coating on the balls has no positive influence on the service life and even appears to reduce it in combination with MoS2.

Keywords: ball bearings, molybdenum disulfide, solid lubricated bearings, solid lubrication mechanisms

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355 A Case Study: Effect of Low Carbs High Fats Diet (Also Known as LCHF Diet) Combined with Fried Foods in Extra Virgin Olive Oil in Patient with Type 2 Diabetes and Central Obesity

Authors: Cristian Baldini

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‘Diabesity’ is a term for diabetes occurring in the context of obesity. The positive effect of LCHF diets (low-carb, high-fat diets) is well documented: LCHF diets are at least as effective as other dietary strategies for reducing body weight, improving glycaemic control, and reducing both hyperinsulinaemia and blood glucose (reduction of HbA1c) in type 2 diabetes and have unique positive effects on blood lipid concentrations and cardiovascular risk factors. Also, in obese insulin-resistant women, food fried in extra-virgin olive oil significantly reduced both insulin and C-peptide responses after a meal. This case study shows that if combined, both dietary strategies produce a strong effect on blood glucose, resulting in a “forced” reduction of exogenous insulin injection to avoid the problem of hypoglycaemia. Blood tests after three months of this dietary treatment show how HbA1c, triglycerides, and blood lipid profile (LDL, HDL, Total Cholesterol) are improved despite the reduction of exogenous insulin injection of 80% with a parallel body weight decrease of 15%. For continuous glucose monitoring (CGM), the patient used FreeStyle Libre before and after the dietary treatment. In order to check general body functions and glycosuria, the patient used the urine test Multistix 10 SG Siemens.

Keywords: diabetes, obesity, diabesity, fat, fried foods

Procedia PDF Downloads 45
354 Investigation of Mechanical and Tribological Property of Graphene Reinforced SS-316L Matrix Composite Prepared by Selective Laser Melting

Authors: Ajay Mandal, Jitendar Kumar Tiwari, N. Sathish, A. K. Srivastava

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A fundamental investigation is performed on the development of graphene (Gr) reinforced stainless steel 316L (SS 316L) metal matrix composite via selective laser melting (SLM) in order to improve specific strength and wear resistance property of SS 316L. Firstly, SS 316L powder and graphene were mixed in a fixed ratio using low energy planetary ball milling. The milled powder is then subjected to the SLM process to fabricate composite samples at a laser power of 320 W and exposure time of 100 µs. The prepared composite was mechanically tested (hardness and tensile test) at ambient temperature, and obtained results indicate that the properties of the composite increased significantly with the addition of 0.2 wt. % Gr. Increment of about 25% (from 194 to 242 HV) and 70% (from 502 to 850 MPa) is obtained in hardness and yield strength of composite, respectively. Raman mapping and XRD were performed to see the distribution of Gr in the matrix and its effect on the formation of carbide, respectively. Results of Raman mapping show the uniform distribution of graphene inside the matrix. Electron back scatter diffraction (EBSD) map of the prepared composite was analyzed under FESEM in order to understand the microstructure and grain orientation. Due to thermal gradient, elongated grains were observed along the building direction, and grains get finer with the addition of Gr. Most of the mechanical components are subjected to several types of wear conditions. Therefore, it is very necessary to improve the wear property of the component, and hence apart from strength and hardness, a tribological property of composite was also measured under dry sliding condition. Solid lubrication property of Gr plays an important role during the sliding process due to which the wear rate of composite reduces up to 58%. Also, the surface roughness of worn surface reduces up to 70% as measured by 3D surface profilometry. Finally, it can be concluded that SLM is an efficient method of fabricating cutting edge metal matrix nano-composite having Gr like reinforcement, which was very difficult to fabricate through conventional manufacturing techniques. Prepared composite has superior mechanical and tribological properties and can be used for a wide variety of engineering applications. However, due to the unavailability of a considerable amount of literature in a similar domain, more experimental works need to perform, such as thermal property analysis, and is a part of ongoing study.

Keywords: selective laser melting, graphene, composite, mechanical property, tribological property

Procedia PDF Downloads 110