Search results for: ITC limited

Authors: Robbie C. Murchison, Ibrahim Küçükdemiral, Andrew Cowell

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Thermal effects are the largest source of dimensional error in precision machining, and a major proportion is caused by ambient temperature variation. The use of coolant is a primary means of mitigating these effects, but there has been limited work on coolant temperature control. This research critically explored whether CNC-machine coolant refrigeration systems adapted to actively compensate for ambient temperature variation could increase machining accuracy. Accuracy data were collected from operators’ checklists for a CNC 5-axis mill and statistically reduced to bias and precision metrics for observations of one day over a sample period of 27 days. Temperature data were collected using three USB dataloggers in ambient air, the chiller inflow, and the chiller outflow. The accuracy and temperature data were analysed using Pearson correlation, then the thermodynamics of the system were described using system identification with MATLAB. It was found that 75% of thermal error is reflected in the hot coolant temperature but that this is negligibly dependent on ambient temperature. The effect of the coolant refrigeration process on hot coolant outflow temperature was also found to be negligible. Therefore, the evidence indicated that it would not be beneficial to adapt coolant chillers to compensate for ambient temperature variation. However, it is concluded that hot coolant outflow temperature is a robust and accessible source of thermal error data which could be used for prevention strategy evaluation or as the basis of other thermal error strategies.

Keywords: CNC manufacturing, machine-tool, precision machining, thermal error

Procedia PDF Downloads 89

Authors: Rachid El Aidani, Phuong Nguyen-Tri, Toan Vu-Khanh

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The filter media in synthetic fibre is the most geotextile materials used in aerosol and drainage filtration, particularly for buildings soil reinforcement in civil engineering due to its appropriated properties and its low cost. However, the current understanding of the durability and stability of this material in real service conditions, especially under severe long-term conditions are completely limited. This study has examined the effects of the chemical aging of a filter media in polyester nonwoven under different temperatures (50, 70 and 80˚C) and pH (2. 7 and 12). The effect of aging conditions on mechanical properties, morphology, permeability, thermal stability and molar weigh changes is investigated. The results showed a significant reduction of mechanical properties in term of tensile strength, puncture force and tearing forces of the filter media after chemical aging due to the chemical degradation. The molar mass and mechanical properties changes in different temperature and pH showed a complex dependence of material properties on environmental conditions. The SEM and AFM characterizations showed a significant impact of the thermal aging on the morphological properties of the fibres. Based on the obtained results, the lifetime of the material in different temperatures was determined by the use of the Arrhenius model. These results provide useful information to better understand phenomena occurring during chemical aging of the filter media and may help to predict the service lifetime of this material in real used conditions.

Keywords: nonwoven membrane, chemical aging, mechanical properties, lifetime, filter media

Procedia PDF Downloads 348

Authors: Mohamed Amine Adaour, Mohamed Sadek Bachene, Mosaab Fortassi, Wafaa Siouda

Abstract:

— Foot infections are responsible for a significant number of hospitalizations and amputations in diabetic patients. The objective of our study is to analyze and evaluate the management of diabetic foot in a surgical setting. A retrospective study was conducted based on a selected case of suspected diabetic foot infections of osteitis treated at the Mohamed Boudiaf hospital in Medea.The case was reiterated as a therapeutic charge, consisting of treating first the infection of the soft tissues, then the osteitis: biopsy after at least 15 days of cessation of antibiotic therapy. Successful treatment of osteitis was defined at the end of a follow-up period of complete wound healing, lack of bone resection/amputation surgery at the initial bone site during follow-up , Instead, biopsies are prescribed in the treatment of soft tissue infection. The mean duration of treatment for soft tissue infection was 2-3 weeks, the duration of the antibiotic-free window of therapy prior to bone biopsy was 2-4 weeks. This patient received medical management without surgical resection. The success rate for treating osteitis at one year was 73%, and healing at one year was 88%.It is often limited to a sausage of the foot at the cost of repeated amputations. The best management remains prevention, which necessarily involves setting up a specialized and adapted centre.

Keywords: diabetic foot, bone biopsy, osteitis, algeria

Procedia PDF Downloads 104

Authors: Chao Hsing Yeh, Wei Chun Lin

Abstract:

Background: Current management of aromatase inhibitor-induced arthralgia (AIA) in postmenopausal breast cancer survivors (PBCS) has limited effect. Method: In this prospective randomized clinical trial (RCT), a 4-week APA treatment was used to manage AIA. Twenty PBCS participated. After baseline data was collected, participants were waited for a month before they receive APA at a convenient time once a week for 4 weeks. Blood samples from participants in both groups were collected at baseline and after 4 weeks of treatment. The primary outcomes included: pain intensity, pain interference, stiffness, and physical function. Results: After the 4-week APA treatment, the pro-inflammatory cytokines and chemokines display a trend of mean percentage reduction (i.e., -22% in IL-1α, -4% in IL-1β, -1% in IL-2, -3% in IL-6, -19% in IL-12, -9% in Eotaxin, and -2% in MCP-1). The anti-inflammatory cytokine IL-10 and IL-13 (i.e., 5% in IL-10 and 29% in IL-13) increased from pre- to post-APA treatment. Significant positive correlation of percentage mean change was observed between symptom severity and eotaxin (ρ = 0.56; p < 0.01) & MCP-1 (ρ = 0.65; p < 0.01). Interference and chemokines (eotaxin & MIP-1) also shows positive correlation (ρ = 0.48; p < 0.01 & ρ = 0.39; p < 0.05). Another positive correlation was found between worst pain and chemokines (eotaxin, ρ = 0.48; p < 0.01 & MIP-1, ρ = 0.39; p < 0.05). Additionally, interference also shows positive correlation among IL-1α (ρ = 0.36; p < 0.05) and IL-β (ρ = 0.33; p < 0.05). Conclusion: These findings suggest that APA intervention may inhibit inflammation of AIA patients and chemokine could be one of the key factors of AIA symptom improvement.

Keywords: acupressure, cytokine, pain management, breast cancer survivors

Procedia PDF Downloads 261

Authors: Nadia Allouache

Abstract:

Energy conservation is one of the major concerns in the modern high tech era due to the limited amount of energy resources and the increasing cost of energy. Predicting an efficient use of energy in thermal systems like heat exchangers can only be achieved if the second law of thermodynamics is accounted for. The performance of heat exchangers can be substantially improved by many passive heat transfer augmentation techniques. These letters permit to improve heat transfer rate and to increase exchange surface, but on the other side, they also increase the friction factor associated with the flow. This raises the question of how to employ these passive techniques in order to minimize the useful energy. The objective of this present study is to use a porous substrate attached to the walls as a passive enhancement technique in heat exchangers and to find the compromise between the hydrodynamic and thermal performances under turbulent flow conditions, by using a second law approach. A modified k- ε model is used to simulating the turbulent flow in the porous medium and the turbulent shear flow is accounted for in the entropy generation equation. A numerical modeling, based on the finite volume method is employed for discretizing the governing equations. Effects of several parameters are investigated such as the porous substrate properties and the flow conditions. Results show that under certain conditions of the porous layer thickness, its permeability, and its effective thermal conductivity the minimum rate of entropy production is obtained.

Keywords: second law approach, annular heat exchanger, turbulent flow, porous medium, modified model, numerical analysis

Procedia PDF Downloads 288

Authors: Yao Xing, Hong Ling Liu, Wei Dong Yu

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With the increase of global population, it is of importance for the safe water supply, while, the water-monitoring method with the capability of rapidness, low-cost, green and robustness remains unsolved. In this paper, gold nanoclusters-wool keratin is added into copper ions measured by fluorescent method in order to probe copper ions in aqueous solution. The fluorescent results show that gold nanoclusters-wool keratin exhibits high stability of pHs, while it is sensitive to temperature and time. Based on Gauss fitting method, the results exhibit that the slope of gold nanoclusters-wool keratin with pH resolution under acidic condition is higher compared to it under alkaline solutions. Besides, gold nanoclusters-wool keratin added into copper ions shows a fluorescence turn-off response transferring from red to blue under UV light, leading to the dramatically decreased fluorescent intensity of gold nanoclusters-wool keratin solution located at 690 nm. Moreover, the limited concentration of copper ions tested by gold nanoclusters-wool keratin system is around 1 µmol/L, which meets the need of detection standards. The fitting slope of Stern-Volmer plot at low concentration of copper ions is larger than it at high concentrations, which indicates that aggregated gold nanoclusters are from small amounts to large numbers with the increasing concentration of copper ions. It is expected to provide novel method and materials for copper ions testing with low cost, high efficiency, and easy operability.

Keywords: gold nanoclusters, copper ions, wool keratin, fluorescence

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Authors: Kumaraamy Sasikumar

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The study was conducted in Vadamarachchi-East in Sri Lanka. Data collection was done for a period of two months from June to July 2011. The main focus of this study was to examine factors contributing to mangrove deforestation within the study area, and resultant impacts from deforestation. The study found that, the main factors that have contributed to deforestation include: Long civil wars in the region, poverty which pushed people to clear the forest to earn income through the sale of firewood and timber among others, industrial development, increasing demand for farm and settlement land, limited knowledge within the local community, weak government polices and implementation strategies, and natural disasters especially the 2004 Tsunami destruction. The impacts presented are those that impact both on the environment and the economy including; loss of income sources, loss of biodiversity, climate change, desertification, conflicts in the use of forest products and loss of land productivity due to reduced fertility caused by soil erosion. However, a few strategies have been put in place by the government to ensure the sustainable use of mangrove forest products, though these have not proved successful in reducing deforestation. The recommendations make suggestions to the government and other stakeholders to work together in ensuring sustainable use of natural resources, for example implementing laws and regulations aimed at controlling deforestation among others.

Keywords: deforestation, impacts, actors, environment, economic, sustainable development

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Authors: John Monro, Suman Mishra

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Choosing foods for health benefits requires information that accurately represents the relative effectiveness of foods with respect to specific health end points, or with respect to responses leading to health outcomes. At present consumers must rely on nutrient composition data, and on health claims to guide them to healthy food choices. Nutrient information may be of limited usefulness because it does not reflect the effect of food structure and food component interactions – that is, whole food effects. Health claims demand stringent criteria that exclude most foods, even though most foods have properties through which they may contribute to positive health outcomes in a diet. In this presentation, we show how the functional efficacy of foods may be expressed in the same format as nutrients, with weight units, as virtual food components that allow a nutrition information panel to show not only what a food is, but also what it does. In the presentation, two body responses linked to well-being are considered – glycaemic response and colonic bulk – in order to illustrate the concept. We show how the nutrient information on available carbohydrates and dietary fibre values obtained by food analysis methods fail to provide information of the glycaemic potency or the colonic bulking potential of foods, because of failings in the methods and approach taken to food analysis. It is concluded that a category of food values that represent the functional efficacy of foods is required to accurately guide food choices for health.

Keywords: dietary fibre, glycaemic response, food values, food effects, health

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Authors: Iram Malik, Mahrukh Shaukat, Abeer Malik, Hafiz Mushtaq Ahmad

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There has been a lot of research on cyberbullying but there is limited research on the topic of accidental cyberbullying on social media with a special focus on healthcare industry. This study emphasizes to uncover the factors that contribute to accidental cyberbullying on social media and how it affects individuals, professionals’ and organizations in health care sector. Nowadays social media is becoming a necessary part of our daily life; there is a need to look into how it is shaping our social life and behaviors displayed online. Instances of cyber bullying can have long-term repercussions due to over-sharing of information. The study used simple random sampling and the instrument of data collection was survey. A sample size of 250 healthcare professionals was chosen from the twin cities of Rawalpindi and Islamabad, Pakistan to examine the relationship between their attitude towards internet use, psychological distress, verbal aggression, envy, frustration, self-compassion, personality traits and accidental cyberbullying on social media. The results of the study have been encouraging. The findings show that psychological distress, aggression, envy, frustration and personality traits had direct effect on accidental cyberbullying whereas compassion, altruism lessened the effect of accidental cyberbullying behavior. It is our intent that the findings of this study could help raise awareness regarding fair use of social media, help policy makers in developing appropriate policies for avoiding cyberbullying in future.

Keywords: accidental cyberbullying, aggression, cyberbullying, frustration, social media

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Authors: Josef Voracek, Jan Sima

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The main purpose of our study is to state the basic types of fitness customers. This paper aims to create a specific customer typology in today’s fitness centres in the region of Prague. Our suggested typology of Prague fitness centres customers is based on answers to the questions: What are the customers like, what are their preferences, and what kinds of services do they use more often in Prague fitness centres? These are the main aspects of the presented typology. A survey was conducted on a sample of 1004 respondents from 48 fitness centres, which ran during May 2012. We used questionnaires and latent class analysis for the assessment and interpretation of data. Gender was especially the main filter criterion. In the population, there were 522 males and 482 females. Data were analysed using the LCA method. We identified 6 segments of typical customers, of which three are male and three are female. Each segment is influenced primarily by the age of customers, from which we can develop further characteristics, such as education, income, marital status, etc. Male segments use the main workout area above all, whilst female segments use a much wider range of services offered, for example, group exercises, personal training, and cardio theatres. LCA method was found to be the most suitable tool, because cluster analysis is very limited in the forms and numbers of variables and indicators. Models of 3 latent classes for each gender are optimal, as it is demonstrated by entropy indices and matrices of the likelihood of the membership to the classes. A probable weak point of the survey is the selection of fitness centres, because of the market in Prague is really specific.

Keywords: customer, fitness, latent class analysis, typology

Procedia PDF Downloads 216

Authors: Gheorghe Giurgiu, Manole Cojocaru, Mihnea Andrei Nicodin

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Background: Inflammation has the main role in the progression of endometriosis. The mechanisms by which endometriosis induces a chronic pain state remain poorly understood. Unfortunately, there is no known cure for endometriosis. But you can manage it with medication and at-home treatments. Some findings have highlighted the main role of inflammation in endometriosis by acting on proliferation, apoptosis, and angiogenesis. The introduction of new agents can be effective in improving the condition of patients; for example, plants are promising sources of bioactive natural components. Objectives: These natural compounds could be interesting strategies in therapy. While there is no absolute cure for this condition, some home remedies can relieve the pain and discomfort it brings. The purpose of this study is to summarize the potential action of Deniplant nutraceuticals in endometriosis by acting on inflammation. Materials and Methods: The primary symptoms of endometriosis are pelvic pain and infertility. The use of Deniplant nutraceuticals could be interesting in disease management for women. Results: Treating pain-related aspects of endometriosis would contribute to the improvement of mental health and daytime function. Because the microbiome can influence inflammation, new therapies can develop through its natural modulation. There are other options, including natural remedies, herbs like cinnamon twigs or licorice root, or supplements such as thiamine, magnesium, or omega-3 fatty acids. Conclusion: Deniplant nutraceuticals can downregulate inflammation in endometriosis. Nevertheless, the limited number of studies focusing on the different interactions of Deniplant nutraceuticals in endometriosis restricts its clear and immediate use in a therapeutic strategy.

Keywords: endometriosis, diet, Deniplant nutraceuticals, pain

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Authors: S. Dikmen Kucuk, A. Tozluoglu, Y. Guner

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In recent years, petroleum-based polymers began to be limited due to effects on human and environmental point of view in many countries. Thus, organic-based biodegradable materials have attracted much interest in the composite industry because of environmental concerns. As a result of this, it has been asked that inorganic and petroleum-based materials should be reduced and altered with biodegradable materials. In this point, in this study, it is aimed to investigate the potential of use of TEMPO (2,2,6,6- tetramethylpiperidine 1-oxyl)-mediated oxidation nano-fibrillated cellulose instead of EPDM (ethylene-propylene-diene monomer) rubber, which is a petroleum-based material. Thus, the exchange of petroleum-based EPDM rubber with organic based cellulose nanofibers, which are environmentally friendly (green) and biodegradable, will be realized. The effect of tempo-oxidized cellulose nanofibers (TCNF) instead of EPDM rubber was analyzed by rheological, mechanical, chemical, thermal and aging analyses. The aged surfaces were visually scrutinized and surface morphological changes were examined via scanning electron microscopy (SEM). The results obtained showed that TEMPO oxidation nano-fibrillated cellulose can be used at an amount of 1.0 and 2.2 phr resulting the values stay within tolerance according to customer standard and without any chemical degradation, crack, colour change or staining.

Keywords: EPDM, cellulose, green materials, nanofibrillated cellulose, TCNF, tempo-oxidized nanofiber

Procedia PDF Downloads 109

Authors: Uhde Serenay Sunay, Alev Yalçınkaya

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Emotional abuse is one of the most challenging forms of violence to define, and many individuals often unknowingly experience emotional abuse. Existing literature has found that individuals who have experienced psychological abuse tend to suffer from depression, low self-esteem, a decreased sense of autonomy, fear, and an increased risk of suicide. Current research indicates that physical abuse in romantic relationships is often accompanied by emotional abuse, supporting the idea that identifying emotional abuse is an essential factor in romantic relationships. On the other hand, studies on emotional abuse between partners in romantic relationships are limited. This study investigated attitudes towards emotional abuse among Turkish university students. Gender differences were investigated.Additionally, the study examined whether the degree of emotional abuse was related to attitudes towards emotional abuse. A total of 243 university students participated in the research, with 156 female and 87 male participants. Participants' attitudes toward emotional abuse were measured using the Turkish adaptation of Follingstad Psychological Aggression Scale and hypothetical scenarios created by the researchers. The results revealed that attitudes of women and men vary significantly in attack looks/sexuality, fidelity, gender roles, and jealousy subscales of Follingstad Psychological Aggression Scale. Furthermore, attitudes towards moderate-level and severe-level emotional abuse exhibit statistically significant variability by gender, while attitudes towards mild-level emotional abuse do not.

Keywords: emotional abuse, gender differences, Turkish culture, university students

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Authors: Jie Huo, Jonathan Wu

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Segmentation of anatomical structures in medical images is essential for scientific inquiry into the complex relationships between biological structure and clinical diagnosis, treatment and assessment. As a method of incorporating the prior knowledge and the anatomical structure similarity between a target image and atlases, multi-atlas segmentation has been successfully applied in segmenting a variety of medical images, including the brain, cardiac, and abdominal images. The basic idea of multi-atlas segmentation is to transfer the labels in atlases to the coordinate of the target image by matching the target patch to the atlas patch in the neighborhood. However, this technique is limited by the pairwise registration between target image and atlases. In this paper, a novel multi-atlas segmentation approach is proposed by introducing a dynamic energy model. First, the target is mapped to each atlas image by minimizing the dynamic energy function, then the segmentation of target image is generated by weighted fusion based on the energy. The method is tested on MICCAI 2012 Multi-Atlas Labeling Challenge dataset which includes 20 target images and 15 atlases images. The paper also analyzes the influence of different parameters of the dynamic energy model on the segmentation accuracy and measures the dice coefficient by using different feature terms with the energy model. The highest mean dice coefficient obtained with the proposed method is 0.861, which is competitive compared with the recently published method.

Keywords: brain MRI segmentation, dynamic energy model, multi-atlas segmentation, energy minimization

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Authors: N. L. Divya Gayatri

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In India, over 377 million urban people generate 62 million tons of municipal solid waste per annum. Forty-three million tons are collected, 11.9 million are treated and 31 million tons is dumped in landfill sites. The study aims to have an overall understanding of the working and functioning of a sanitary landfill from the siting to the closure stage and identifying various landscape design techniques that can be implemented in a landfill site and come up with a set of guidelines by analyzing the existing policies and guidelines pertaining to landfills. Constituents of municipal solid waste, methods of landfilling, issues, impacts, Mitigation strategies, Landscape design strategies, design approaches towards a landfill, infrastructure requirements, end-use opportunities have been discussed. The objective is to study the ecological and environmental degradation prevention methods, compare various techniques in remediation, study issues in landfill sites in India, analyze scope and opportunities and explore various landscape design strategies. The understanding of the function of landfills with respect to Municipal solid waste and landscaping is conveyed through this study. The study is limited to Landscape design factors in landfill design guidelines and policies mentioned with regard to the issues and impacts specific to the Indian context.

Keywords: sanitary landfill landscaping, environmental impact, municipal solid waste, guidelines, landscape design strategies, landscape design approaches

Procedia PDF Downloads 156

Authors: Mohamed Amine Adaour, Mohamed Sadek Bachene, Mosaab Fortassi, Wafaa Siouda

Abstract:

Foot infections are responsible for a significant number of hospitalizations and amputations in diabetic patients. The objective of our study is to analyze and evaluate the management of diabetic foot in a surgical setting. A retrospective study was conducted based on a selected case of suspected diabetic foot infections of osteitis treated at the Mohamed Boudiaf hospital in Medea. The case was reiterated as a therapeutic charge, consisting of treating first the infection of the soft tissues, then the osteitis: biopsy after at least 15 days of cessation of antibiotic therapy. Successful treatment of osteitis was defined at the end of a follow-up period of complete wound healing, lack of bone resection/amputation surgery at the initial bone site during follow-up , Instead, biopsies are prescribed in the treatment of soft tissue infection. The mean duration of treatment for soft tissue infection was 2-3 weeks, the duration of the antibiotic-free window of therapy prior to bone biopsy was 2-4 weeks. This patient received medical management without surgical resection. The success rate for treating osteitis at one year was 73%, and healing at one year was 88%.It is often limited to a sausage of the foot at the cost of repeated amputations. The best management remains prevention, which necessarily involves setting up a specialized and adapted centre.

Keywords: osteitis, antibiotic therapy, bone biopsy, diabetic foot

Procedia PDF Downloads 82

Authors: Qing Zhang, Jiachen Nie, Yujia Wen, Guanyuan Kou, Peng Yu, Kun Xia, Qin Yang, Li Ding

Abstract:

BACKGROUND: A facility layout problem (FLP) is an NP-complete (non-deterministic polynomial) problem, which is hard to obtain an exact optimal solution. FLP has been widely studied in various limited spaces and workflows. For example, cafeterias with many types of equipment for troops cause chaotic processes when dining. OBJECTIVE: This article tried to optimize the layout of troops’ cafeteria and to improve the overall efficiency of the dining process. METHODS: First, the original cafeteria layout design scheme was analyzed from an ergonomic perspective and two new design schemes were generated. Next, three facility layout models were designed, and further simulation was applied to compare the total time and density of troops between each scheme. Last, an experiment of the dining process with video observation and analysis verified the simulation results. RESULTS: In a simulation, the dining time under the second new layout is shortened by 2.25% and 1.89% (p<0.0001, p=0.0001) compared with the other two layouts, while troops-flow density and interference both greatly reduced in the two new layouts. In the experiment, process completing time and the number of interference reduced as well, which verified corresponding simulation results. CONCLUSIONS: Our two new layout schemes are tested to be optimal by a series of simulation and space experiments. In future research, similar approaches could be applied when taking layout-design algorithm calculation into consideration.

Keywords: layout optimization, dining efficiency, troops’ cafeteria, anylogic simulation, field experiment

Procedia PDF Downloads 143

Authors: M. Rouhani, F. C. N. Hong, Y. R. Jeng

Abstract:

The tribological performance of DLC films is limited by graphitization at elevated temperatures. Despite of numerous studies on the thermal stability of DLC films, a comprehensive in-situ characterization at elevated temperature is still lacking. In this study, DLC films were deposited using filtered cathodic arc vacuum method. Thermal stability of the films was characterized in-situally using a synchronized technique integrating Raman spectroscopy and depth-sensing measurements. Tests were performed in a high temperature chamber coupled with feedback control to make it possible to study the temperature effects in the range of 21 – 450 ̊C. Co-located SPM and Raman microscopy maps at different temperature over a specific area on the surface of the film were prepared. The results show that the thermal stability of the DLC films depends on their sp3 content. Films with lower sp3 content endure graphitization during the temperature-course used in this study. The graphitization is accompanied with significant changes in surface roughness and Raman spectrum of the film. Surface roughness of the films start to change even before graphitization transformation could be detected using Raman spectroscopy. Depth-sensing tests (nanoindentation, nano-scratch and wear) endorse the surface roughness change seen before graphitization occurrence. This in-situ study showed that the surface of the films is more sensitive to temperature rise compared to the bulk. We presume the changes observed in films hardness, surface roughness and scratch resistance with temperature rise, before graphitization occurrence, is due to surface relaxation.

Keywords: DLC film, nanoindentation, Raman spectroscopy, thermal stability

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Authors: Peter K. Galenko, Stefanie Koch, Markus Rettenmayr, Robert Wonneberger, Evgeny V. Kharanzhevskiy, Maria Zamoryanskaya, Vladimir Ankudinov

Abstract:

We analyze the structure of undercooled melts, crystal growth kinetics and amorphous/crystalline microstructure of rapidly solidifying glass-forming Pd-based and CuZr-based alloys. A dendrite growth model is developed using a combination of the kinetic phase-field model and mesoscopic sharp interface model. The model predicts features of crystallization kinetics in alloys from thermodynamically controlled growth (governed by the Gibbs free energy change on solidification) to the kinetically limited regime (governed by atomic attachment-detachment processes at the solid/liquid interface). Comparing critical undercoolings observed in the crystallization kinetics with experimental data on melt viscosity, atomistic simulation's data on liquid microstructure and theoretically predicted dendrite growth velocity allows us to conclude that the dendrite growth kinetics strongly depends on the cluster structure changes of the melt. The obtained data of theoretical and experimental investigations are used for interpretation of microstructure of samples processed in electro-magnetic levitator on board International Space Station in the frame of the project "MULTIPHAS" (European Space Agency and German Aerospace Center, 50WM1941) and "KINETIKA" (ROSKOSMOS).

Keywords: dendrite, kinetics, model, solidification

Procedia PDF Downloads 120

Authors: Mohamed Amine Adaour, Mohamed Sadek Bachene, Mosaab Fortassi, Wafaa Siouda

Abstract:

Foot infections are responsible for a significant number of hospitalizations and amputations in diabetic patients. The objective of our study is to analyze and evaluate the management of diabetic foot in a surgical setting. A retrospective study was conducted based on a selected case of suspected diabetic foot infections of osteitis treated at the Mohamed Boudiaf hospital in Medea.The case was reiterated as a therapeutic charge, consisting of treating first the infection of the soft tissues, then the osteitis: biopsy after at least 15 days of cessation of antibiotic therapy. Successful treatment of osteitis was defined at the end of a follow-up period of complete wound healing, lack of bone resection/amputation surgery at the initial bone site during follow-up , Instead, biopsies are prescribed in the treatment of soft tissue infection. The mean duration of treatment for soft tissue infection was 2-3 weeks, the duration of the antibiotic-free window of therapy prior to bone biopsy was 2-4 weeks. This patient received medical management without surgical resection. The success rate for treating osteitis at one year was 73%, and healing at one year was 88%.It is often limited to a sausage of the foot at the cost of repeated amputations. The best management remains prevention, which necessarily involves setting up a specialized and adapted centre.

Keywords: osteitis, antibiotic, biopsy, diabetic foot

Procedia PDF Downloads 99

Authors: Megha Agarwal

Abstract:

The research paper is an effort to compare the earnings based and cash flow based methods of valuation of an enterprise. The theoretically equivalent methods based on either earnings such as Residual Earnings Model (REM), Abnormal Earnings Growth Model (AEGM), Residual Operating Income Method (ReOIM), Abnormal Operating Income Growth Model (AOIGM) and its extensions multipliers such as price/earnings ratio, price/book value ratio; or cash flow based models such as Dividend Valuation Method (DVM) and Free Cash Flow Method (FCFM) all provide different estimates of valuation of the Indian giant corporate Reliance India Limited (RIL). An ex-post analysis of published accounting and financial data for four financial years from 2008-09 to 2011-12 has been conducted. A comparison of these valuation estimates with the actual market capitalization of the company shows that the complex accounting based model AOIGM provides closest forecasts. These different estimates may be derived due to inconsistencies in discount rate, growth rates and the other forecasted variables. Although inputs for earnings based models may be available to the investor and analysts through published statements, precise estimation of free cash flows may be better undertaken by the internal management. The estimation of value from more stable parameters as residual operating income and RNOA could be considered superior to the valuations from more volatile return on equity.

Keywords: earnings, cash flows, valuation, Residual Earnings Model (REM)

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Authors: Tomasz Borowski, Dawid Sołoducha, Rafał Rakoczy, Marian Kordas

Abstract:

The application of magnetic field is essential for a wide range of technologies or processes (i.e., magnetic hyperthermia, bioprocessing). From the practical point of view, bioprocess control is often limited to the regulation of temperature at constant values favourable to microbial growth. The main aim of this study is to determine the effect of various types of electromagnetic fields (i.e., static or alternating) on the heat transfer in a self-designed magnetically assisted reactor. The experimental set-up is equipped with a measuring instrument which controlled the temperature of the liquid inside the container and supervised the real-time acquisition of all the experimental data coming from the sensors. Temperature signals are also sampled from generator of magnetic field. The obtained temperature profiles were mathematically described and analyzed. The parameters characterizing the response to a step input of a first-order dynamic system were obtained and discussed. For example, the higher values of the time constant means slow signal (in this case, temperature) increase. After the period equal to about five-time constants, the sample temperature nearly reached the asymptotic value. This dynamical analysis allowed us to understand the heating effect under the action of various types of electromagnetic fields. Moreover, the proposed mathematical description can be used to compare the influence of different types of magnetic fields on heat transfer operations.

Keywords: heat transfer, magnetically assisted reactor, dynamical analysis, transient function

Procedia PDF Downloads 172

Authors: Khwaja Bahman Qaderi, Noorullah Rafiqee

Abstract:

Background: With today's increasing Internet users, e-commerce has become a viable model for strengthening relationships between sellers, entrepreneurs, and consumers due to its speed, efficiency, and cost reduction. Agriculture is the economic backbone for 80 percent of the Afghan population. According to MCIT statistics, there are currently around 10 million internet users in Afghanistan. With this data, it was expected that Afghan people should have utilized e-commerce in their agricultural aspects, although it appears to be less used. Objective: This study examines the scope of e-commerce in Afghanistan's agriculture enterprises, how they harness the potential of internet users, and what obstacles they face in implementing e-commerce in their businesses. Method: The study distributed a 39-question questionnaire to agribusinesses in five different zones of Afghanistan. After extracting the responses and excluding the incomplete questionnaires, 280 were included in the analysis step to perform a non-parametric sign test. Result: E-commerce in Afghanistan faces four major political, economic, Internet, and technological obstacles, and no company in the country has implemented e-commerce. In addition, e-commerce is still in its infancy among agricultural companies in the country. Internet use is still primarily limited to email and sharing product images on Facebook & Instagram for advertising purposes. There are no companies that conduct international transactions via the Internet. Conclusion: This study contributes to knowing the challenges and barriers that the agriculture e-commerce faces in Afghanistan to find the effective solutions to use the capacity of internet users in the country and increase the sales rate of agricultural products through the Internet.

Keywords: E-commerce, barriers and challenges, agriculture companies, Afghanistan

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Authors: Mehdi Bakhtiarzadeh, Reza Efatnejad, Kambiz Rezapour Rezapour

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Due to the limited resources of fossil fuels and their harmful effects on the environment and human health, research on renewable energy applications in industrial and scientific communities has become particularly important. Only one percent of freshwater resources are available for use in the domestic, agricultural, and industrial sectors. On the other hand, the rapid growth of industry and the increase of population in most countries of the world, including Iran, have led to an increase in demand for freshwater. Among renewable energies, there is the potential of solar energy in Iran. As a result, solar distillation systems can be used as a solution to supply fresh water in remote rural areas. Therefore, in the present study, a solar water desalination device was designed and manufactured using two heat exchangers and a photovoltaic system. Its evaluation was done during September and October of 2020. During the evaluation of the device, environmental variables such as total solar radiation, ambient temperature and cooling tower temperature were recorded at intervals of one hour from 9 am to 5 pm. The effect of these variables on solar concentrator performance, heat exchanger, and daily freshwater production was evaluated. The results showed that using two heat exchangers and a photovoltaic system has led to the daily production of 5 liters of fresh water and 46% economic efficiency.

Keywords: solar water desalination, heat exchanger, photovoltaic system, technical and economic evaluation

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Authors: Misbah Fatma, Anam Saiyeda

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This analysis charts the introduction and expansion of research into the filter bubble phenomena over the last 10 years using a large dataset of academic publications. This bibliometric study demonstrates how interdisciplinary filter bubble research is. The identification of key authors and organizations leading the filter bubble study sheds information on collaborative networks and knowledge transfer. Relevant papers are organized based on themes including algorithmic bias, polarisation, social media, and ethical implications through a systematic examination of the literature. In order to shed light on how these patterns have changed over time, the study plots their historical history. The study also looks at how research is distributed globally, showing geographic patterns and discrepancies in scholarly output. The results of this bibliometric analysis let us fully comprehend the development and reach of filter bubble research. This study offers insights into the ongoing discussion surrounding information personalization and its implications for societal discourse, democratic participation, and the potential risks to an informed citizenry by exposing dominant themes, interdisciplinary collaborations, and geographic patterns. In order to solve the problems caused by filter bubbles and to advance a more diverse and inclusive information environment, this analysis is essential for scholars and researchers.

Keywords: bibliometric analysis, social media, social networking, algorithmic personalization, self-selection, content moderation policies and limited access to information, recommender system and polarization

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Authors: Samanta Tiague, Igor Michel Gachig

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The practice of inclusive education within general education classrooms is becoming more prevalent in Cameroon. In this context, quality Education is an important driver of the development agenda in this era of global sustainable development. This requires that the Cameroon’s educational system be strategically restructured to provide every citizen with the needed quality education for sustainable development. This study thus examined the need for the restructuring of the Cameroon educational system towards inclusive education as a target of the Sustainable Development Goal #4 (Ensure Quality Education), from a critical disability theory perspective. Special focus was on the education of children with visual impairment in the early childhood classroom. This study is suggesting a model design of responsive and contextual inclusive education policies, and the provision of quality human, material and financial educational resources to support the improvement of curriculums and inclusive instructional strategies. This paper is therefore designed as a basic starting point for early childhood educators with limited to no experience in working with students having visual impairments. Ultimately, this work represents a contribution to early childhood educators toward understanding visual impairment challenges and innovative practices to approach accessibility in a meaningful way to students in Cameroon. This is important to achieve quality education due to the peculiar nature of the educational needs of children with visual impairment, toward attainment of the global sustainable development agenda.

Keywords: early childhood educators, inclusive education, sustainable development, visual impairment

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Authors: Deng Zengming, Wang Mingjiang

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As 3D video is explored as a hot research topic in the last few decades, free-viewpoint TV (FTV) is no doubt a promising field for its better visual experience and incomparable interactivity. View synthesis is obviously a crucial technology for FTV; it enables to render images in unlimited numbers of virtual viewpoints with the information from limited numbers of reference view. In this paper, a novel hybrid synthesis framework is proposed and blending priority is explored. In contrast to the commonly used View Synthesis Reference Software (VSRS), the presented synthesis process is driven in consideration of the temporal correlation of image sequences. The temporal correlations will be exploited to produce fine synthesis results even near the foreground boundaries. As for the blending priority, this scheme proposed that one of the two reference views is selected to be the main reference view based on the distance between the reference views and virtual view, another view is chosen as the auxiliary viewpoint, just assist to fill the hole pixel with the help of background information. Significant improvement of the proposed approach over the state-of –the-art pixel-based virtual view synthesis method is presented, the results of the experiments show that subjective gains can be observed, and objective PSNR average gains range from 0.5 to 1.3 dB, while SSIM average gains range from 0.01 to 0.05.

Keywords: fusion method, Gaussian mixture model, hybrid framework, view synthesis

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Authors: Rizky Kusuma Cahyani

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Hepatitis B is a liver inflammatory disease caused by hepatitis B virus (HBV). This infection can be prevented by vaccination which contains HBV surface protein (sHBsAg). However, vaccine supply is limited. Several attempts have been conducted to produce local sHBsAg. However, the purity degree and protein yield are still inadequate. Therefore optimization of HBsAg purification steps is required to obtain high yield with better purification fold. In this study, optimization of purification was done in 2 steps, precipitation using variation of NaCl concentration (0,3 M; 0,5 M; 0,7 M) and PEG (3%, 5%, 7%); ion exchange chromatography (IEC) using NaCl 300-500 mM elution buffer concentration.To determine HBsAg protein, bicinchoninic acid assay (BCA) and enzyme-linked immunosorbent assay (ELISA) was used in this study. Visualization of HBsAg protein was done by SDS-PAGE analysis. Based on quantitative analysis, optimal condition at precipitation step was given 0,3 M NaCl and PEG 3%, while in ion exchange chromatography step, the optimum condition when protein eluted with NaCl 500 mM. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis indicates that the presence of protein HBsAg with a molecular weight of 25 kDa (monomer) and 50 kDa (dimer). The optimum condition for purification of sHBsAg produced in Pichia pastoris gave a yield of 47% and purification fold 17x so that it would increase the production of hepatitis B vaccine to be more optimal.

Keywords: hepatitis B virus, HBsAg, hepatitis B surface antigen, Pichia pastoris, purification

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Authors: E. Lacasa, J. L. Santolaya, I. Millán

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The progress toward sustainability implies maintaining and preferably improving both, human and ecosystem well-being, according to a triple bottom line that includes the environmental, economic and social dimensions. The life cycle assessment (LCA) is a method applicable to all production sectors that aims to quantify the environmental pressures and the benefits related to goods and services, as well as the trade-offs and the scope for improving areas of the production process. While using LCA to measure the environmental dimension of sustainability is widespread, similar approaches for the economic and the social dimensions still have limited application worldwide and there is a need for consistent and robust methods and indicators. This paper focuses on the milk production process and presents the analysis of the flows exchanged by an industrial installation through accounting all the energy and material inputs and the associated emissions and waste outputs at this stage of its life cycle. The functional unit is one litre of milk produced. Different metrics and indicators are used to assess the three dimensions of sustainability. Metrics considered useful to assess the production activities are the total water and energy consumptions and the milk production volume of each cow. The global warming, the value added and the working hours are indicators used to measure each sustainability dimension. The study is performed with two types of feeding of the cows, which includes a change in percentages of components as well. Nutritional composition of the milk obtained is almost kept. It is observed that environmental and social improvements involve high economic costs.

Keywords: milk production, sustainability, indicators, life cycle assessment

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Authors: Csaba Barnabas Horvath

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The Belt and Road initiative of China is one that can change the face of Eurasia as we know it. Instead of four major, densely populated subcontinents defined by Mackinder (East Asia, Europe, the Indian Subcontinent, and the Middle East) isolated from each other by vast, sparsely populated and underdeveloped regions, it can at last start to function as a geographic whole, with a sophisticated infrastructure linking its different parts to each other. This initiative, however, happens not in a geopolitical vacuum, but in a space of conflicting great power interests. In Central Asia, the influence of China and Russia are in a setting of competition, where despite the cooperation between the two powers to a great degree, issues causing mutual mistrust emerge repeatedly. In Afghanistan, besides western military presence, even India’s efforts can be added to the picture. In Southeast Asia, a key region regarding the maritime Silk Road, India’s Act East policy meets with China’s Belt and Road, not always in consensus, not to mention US and Japanese interests in the region. The presentation aims to take an overview on how conflicting great power interests are likely to influence the outcome of the Belt and Road initiative. The findings show, that overall success of the Belt and Road Initiative may not be as smooth, as hoped by China, but at the same time, in a limited number of strategically important countries (such as Pakistan, Laos, and Cambodia), this setting is actually a factor favoring China, providing at least a selected number of reliable corridors, where the initiative is actually likely to be successful.

Keywords: belt and road initiative, geostrategic corridors, geopolitics, great power rivalry

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