Search results for: rhetoric of free choice
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5184

Search results for: rhetoric of free choice

4764 A Phenomenological Expression for Self-Attractive Energy of Singlelayer Graphene Sheets

Authors: Bingjie Wu, C. Q. Ru

Abstract:

The present work studies several reasonably expected candidate integral forms for self-attractive potential energy of a free monolayer graphene sheet. The admissibility of a specific integral form for ripple formation is verified, while all others most of the candidate integral forms are rejected based on the non-existence of stable periodic ripples. Based on the selected integral form of self-attractive potential energy, some mechanical behavior, including ripple formation and buckling, of a free monolayer grapheme sheet are discussed in details

Keywords: graphene, monolayer, ripples, van der Waals energy

Procedia PDF Downloads 392
4763 Different Contexts Activate Different Frames: Deepening and Broadening Goal-Framing Theory for Sustainable Food Behaviour

Authors: Marleen Onwezen

Abstract:

It is often assumed that specific consumer groups do or do not have a sustainable lifestyle or that a specific context does or does not trigger sustainable choices. Based on goal-framing theory, this article aims to understand variation in sustainable choices across contexts. We add to the literature by showing the added value of including a moral goal frame (Study 1; N = 1,100) beyond the hedonic, gain, and normative goal frames. Moreover, we add to the literature by revealing how these goal frames are recalled in real-life consumption contexts (Study 2; N = 1,100) and how they can be activated (Study 3; N = 1,651). The results reveal that different goal frames result in different preferences and consumption choices, and that the normative frames showed the most consistent association with sustainable intentions. A contrast exists between frames currently activated in food choice contexts, mainly the gain and hedonic frames, and those associated with sustainable behaviours, the moral and social frames. This indicates the relevance of further understanding and adapting the environment to activate moral and social frames to further enforce sustainable food transitions.

Keywords: goal frames, sustainable behaviour, food choice, moral

Procedia PDF Downloads 136
4762 A Mathematical Model for Hepatitis B Virus Infection and the Impact of Vaccination on Its Dynamics

Authors: T. G. Kassem, A. K. Adunchezor, J. P. Chollom

Abstract:

This paper describes a mathematical model developed to predict the dynamics of Hepatitis B virus (HBV) infection and to evaluate the potential impact of vaccination and treatment on its dynamics. We used a compartmental model expressed by a set of differential equations based on the characteristic of HBV transmission. With these, we find the threshold quantity R0, then find the local asymptotic stability of disease free equilibrium and endemic equilibrium. Furthermore, we find the global stability of the disease free and endemic equilibrium.

Keywords: hepatitis B virus, epidemiology, vaccination, mathematical model

Procedia PDF Downloads 325
4761 Craniopharyngiomas: Surgical Techniques: The Combined Interhemispheric Sub-Commissural Translaminaterminalis Approach to Tumors in and Around the Third Ventricle: Neurological and Functional Outcome

Authors: Pietro Mortini, Marco Losa

Abstract:

Objective: Resection of large lesions growing into the third ventricle remains a demanding surgery, sometimes at risk of severe post-operative complications. Transcallosal and transcortical routes were considered as approaches of choice to access the third ventricle, however neurological consequences like memory loss have been reported. We report clinical results of the previously described combined interhemispheric sub-commissural translaminaterminalis approach (CISTA) for the resection of large lesions located in the third ventricle. Methods: Authors conducted a retrospective analysis on 10 patients, who were operated through the CISTA, for the resection of lesions growing into the third ventricle. Results: Total resection was achieved in all cases. Cognitive worsening occurred only in one case. No perioperative deaths were recorded and, at last follow-up, all patients were alive. One year after surgery 80% of patients had an excellent outcome with a KPS 100 and Glasgow Outcome score (GOS) Conclusion: The CISTA represents a safe and effective alternative to transcallosal and transcortical routes to resect lesions growing into the third ventricle. It allows for a multiangle trajectory to access the third ventricle with a wide working area free from critical neurovascular structures, without any section of the corpus callosum, the anterior commissure and the fornix.

Keywords: craniopharingioma, surgery, sub-commissural translaminaterminalis approach (CISTA),

Procedia PDF Downloads 293
4760 Label Free Detection of Small Molecules Using Surface-Enhanced Raman Spectroscopy with Gold Nanoparticles Synthesized with Various Capping Agents

Authors: Zahra Khan

Abstract:

Surface-Enhanced Raman Spectroscopy (SERS) has received increased attention in recent years, focusing on biological and medical applications due to its great sensitivity as well as molecular specificity. In the context of biological samples, there are generally two methodologies for SERS based applications: label-free detection and the use of SERS tags. The necessity of tagging can make the process slower and limits the use for real life. Label-free detection offers the advantage that it reports direct spectroscopic evidence associated with the target molecule rather than the label. Reproducible, highly monodisperse gold nanoparticles (Au NPs) were synthesized using a relatively facile seed-mediated growth method. Different capping agents (TRIS, citrate, and CTAB) were used during synthesis, and characterization was performed. They were then mixed with different analyte solutions before drop-casting onto a glass slide prior to Raman measurements to see which NPs displayed the highest SERS activity as well as their stability. A host of different analytes were tested, both non-biomolecules and biomolecules, which were all successfully detected using this method at concentrations as low as 10-3M with salicylic acid reaching a detection limit in the nanomolar range. SERS was also performed on samples with a mixture of analytes present, whereby peaks from both target molecules were distinctly observed. This is a fast and effective rapid way of testing samples and offers potential applications in the biomedical field as a tool for diagnostic and treatment purposes.

Keywords: gold nanoparticles, label free, seed-mediated growth, SERS

Procedia PDF Downloads 127
4759 Dynamic Reroute Modeling for Emergency Evacuation: Case Study of Brunswick City, Germany

Authors: Yun-Pang Flötteröd, Jakob Erdmann

Abstract:

The human behaviors during evacuations are quite complex. One of the critical behaviors which affect the efficiency of evacuation is route choice. Therefore, the respective simulation modeling work needs to function properly. In this paper, Simulation of Urban Mobility’s (SUMO) current dynamic route modeling during evacuation, i.e. the rerouting functions, is examined with a real case study. The result consistency of the simulation and the reality is checked as well. Four influence factors (1) time to get information, (2) probability to cancel a trip, (3) probability to use navigation equipment, and (4) rerouting and information updating period are considered to analyze possible traffic impacts during the evacuation and to examine the rerouting functions in SUMO. Furthermore, some behavioral characters of the case study are analyzed with use of the corresponding detector data and applied in the simulation. The experiment results show that the dynamic route modeling in SUMO can deal with the proposed scenarios properly. Some issues and function needs related to route choice are discussed and further improvements are suggested.

Keywords: evacuation, microscopic traffic simulation, rerouting, SUMO

Procedia PDF Downloads 194
4758 Estimation of Emanation Properties of Kimberlites and Host Rocks of Lomonosov Diamond Deposit in Russia

Authors: E. Yu. Yakovlev, A. V. Puchkov

Abstract:

The study is devoted to experimental work on the assessment of emanation properties of kimberlites and host rocks of the Lomonosov diamond deposit of the Arkhangelsk diamondiferous province. The aim of the study is estimation the factors influencing on formation of the radon field over kimberlite pipes. For various types of rocks composing the kimberlite pipe and near-pipe space, the following parameters were measured: porosity, density, radium-226 activity, activity of free radon and emanation coefficient. The research results showed that the largest amount of free radon is produced by rocks of near-pipe space, which are the Vendian host deposits and are characterized by high values of the emanation coefficient, radium activity and porosity. The lowest values of these parameters are characteristic of vent-facies kimberlites, which limit the formation of activity of free radon in body of the pipe. The results of experimental work confirm the prospects of using emanation methods for prospecting of kimberlite pipes.

Keywords: emanation coefficient, kimberlites, porosity, radon volumetric activity

Procedia PDF Downloads 139
4757 The Impact of Green Building Envelopes on the Urban Microclimate of the Urban Canopy-Case Study: Fawzy Moaz Street, Alexandria, Egypt

Authors: Amany Haridy, Ahmed Elseragy, Fahd Omar

Abstract:

The issue of temperature increase in the urban microclimate has been at the center of attention recently, especially in dense urban areas, such as the City of Alexandria in Egypt, where building surfaces have become the dominant element (more than green areas and streets). Temperatures have been rising during daytime as well as nighttime, however, the research focused on the rise of air temperature at night, a phenomenon known as the urban heat island. This phenomenon has many effects on ecological life, as well as human health. This study provided evidence of the possibility of reducing the urban heat island by using a green building envelope (green wall and green roof) in Alexandria, Egypt. This City has witnessed a boom in growth in its urban fabric and population. A simulation analysis using the Envi-met software to find the ratio of air temperature reduction was performed. The simulation depended on the orientation of the green areas and their density, which was defined through a process of climatic analysis made by the Diva plugin using the Grasshopper software. Results showed that the reduction in air temperature varies from 0.8–2.0 °C, increasing with the increasing density of green areas. Many systems of green wall and green roof can be found in the local market. However, treating an existing building requires a careful choice of system to fit the building construction load and the surrounding nature. Among the systems of choice, there was the ‘geometric system’ of vertical greening that can be fixed on a light aluminum structure for walls and the extensive green system for roofs. Finally, native plants were the best choice in the long term because they fare well in the local climate.

Keywords: envi-met, green building envelope, urban heat island, urban microclimate

Procedia PDF Downloads 209
4756 Prescription of Maintenance Fluids in the Emergency Department

Authors: Adrian Craig, Jonathan Easaw, Rose Jordan, Ben Hall

Abstract:

The prescription of intravenous fluids is a fundamental component of inpatient management, but it is one which usually lacks thought. Fluids are a drug, which like any other can cause harm when prescribed inappropriately or wrongly. However, it is well recognised that it is poorly done, especially in the acute portals. The National Institute for Health and Care Excellence (NICE) recommends 1mmol/kg of potassium, sodium, and chloride per day. With various options of fluids, clinicians tend to face difficulty in choosing the most appropriate maintenance fluid, and there is a reluctance to prescribe potassium as part of an intravenous maintenance fluid regime. The aim was to prospectively audit the prescription of the first bag of intravenous maintenance fluids, the use of urea and electrolytes results to guide the choice of fluid and the use of fluid prescription charts, in a busy emergency department of a major trauma centre in Stoke-on-Trent, United Kingdom. This was undertaken over a week in early November 2016. Of those prescribed maintenance fluid only 8.9% were prescribed a fluid which was most appropriate for their daily electrolyte requirements. This audit has helped to highlight further the issues that are faced in busy Emergency Departments within hospitals that are stretched and lack capacity for prompt transfer to a ward. It has supported the findings of NICE, that emergency admission portals such as Emergency Departments poorly prescribed intravenous fluid therapy. The findings have enabled simple steps to be taken to educate clinicians about their fluid of choice. This has included: posters to remind clinicians to consider the urea and electrolyte values before prescription, suggesting the inclusion of a suggested intravenous fluid of choice in the prescription chart of the trust and the inclusion of a session within the introduction programme revising intravenous fluid therapy and daily electrolyte requirements. Moving forward, once the interventions have been implemented then, the data will be reaudited in six months to note any improvement in maintenance fluid choice. Alongside this, an audit of the rate of intravenous maintenance fluid therapy would be proposed to further increase patient safety by avoiding unintentional fluid overload which may cause unnecessary harm to patients within the hospital. In conclusion, prescription of maintenance fluid therapy was poor within the Emergency Department, and there is a great deal of opportunity for improvement. Therefore, the measures listed above will be implemented and the data reaudited.

Keywords: chloride, electrolyte, emergency department, emergency medicine, fluid, fluid therapy, intravenous, maintenance, major trauma, potassium, sodium, trauma

Procedia PDF Downloads 324
4755 Research on Models and Selection of Entry Strategies for Catering Industry Based on the Evolutionary Game Theory

Authors: Jianxin Zhu, Na Liu

Abstract:

Entry strategies play a vital role in the development of new enterprises in the catering industry. Different entry strategies will have different effects on the development of new enterprise. Based on the research of scholars at home and abroad, and combining the characteristics of the catering industry, the entry strategies are divided into low-price entry strategies and high-quality entry strategies. Facing the entry of new enterprise, the strategies of incumbent enterprises are divided into response strategies and non-response strategies. This paper uses evolutionary game theory to study the strategic interaction mechanism between incumbent companies and new enterprises. When different initial values and parameter values are set, which strategy will the two-game subjects choose, respectively? Using matlab2016 for numerical simulation, the results show that the choice of strategies for new enterprise and incumbent enterprise is influenced by more than one factor, and the system has different evolution trends under different circumstances. When the parameters were set, the choice of two subjects' strategies mainly depends on the net profit between the strategies.

Keywords: catering industry, entry strategy, evolutionary game, strategic interaction mechanism

Procedia PDF Downloads 134
4754 A Study to Assess the Employment Ambitions of Graduating Students from College of Applied Medical Sciences, King Saud Bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia

Authors: J. George, M. Al Mutairi, W. Aljuryyad, A. Alhussanan, A. Alkashan, T. Aldoghiri, Z. Alamari, A. Albakr

Abstract:

Introduction: Students make plans for their career and are keen in exploring options of employment in those carriers. They make their employment choice based on their desires and preferences. This study aims to identify if students of King Saud Bin Abdulaziz for Health Sciences, College of Applied Medical Sciences after obtaining appropriate education prefer to work as clinicians, university faculty, or full-time researchers. There are limited studies in Saudi Arabia exploring the university student’s employment choices and preferences. This study would help employers to build the required job positions and prevent misleading employers from opening undesired positions in the job market. Methodology: The study included 394 students from third and fourth years both male and female among the eighth programs of college of applied medical sciences, King Saud Bin Abdulaziz University for Health Sciences (KSAU-HS), Riyadh campus. A prospective quantitative cross-sectional study was conducted; data were collected by distributing a seven item questionnaire and analyzed using SPSS. Results: Among the participants, 358 (90.9%) of them chose one of the three listed career choices, 263 (66.8%) decided to work as hospital staff after their education, 75 students (19.0%) chose to work as a faculty member in a university after obtaining appropriate degree, 20 students (5.1%) preferred to work as full-time researcher after obtaining appropriate degree, the remaining 36 students (9.1%) had different career goals, such as obtaining a master degree after graduating, to obtain a bachelor of medicine and bachelor in surgery degree, and working in the private sector. The most recurrent reason behind the participants' choice was "career goal", where 276 (70.1%) chose it as a reason. Conclusion: The findings of the study showed that most student’s preferred to work in hospitals as clinicians, followed by choice of working as a faculty in a university, the least choice was to be working as full-time researchers.

Keywords: College of Applied Medical Sciences, employment ambitions, graduating students, King Saud bin Abdulaziz University for Health Sciences

Procedia PDF Downloads 162
4753 The Use of Superplastic Tin-Lead Alloy as A solid Lubricant in Free Upsetting of Aluminum and Brass

Authors: Adnan I. O. Zaid, Hebah B. Melhem, Ahmad Qandil

Abstract:

The main function of a lubricant in any forming process is to reduce friction between the work piece and the die set, hence reducing the force and energy requirement for forming process and to achieve homogeneous deformation. The free upsetting test is an important open forging test. In this paper, super plastic tin-lead alloy is used as solid lubricant in the free upsetting test of non-ferrous metals and compared with eight different lubricants using the following three criteria: one comparing the value of the reduction in height percentages, i.e. the engineering strain, in identical specimens of the same material under the effect of the same compressive force. The second is comparing the amount of barreling produced in each of the identical specimens, at each lubricant. The third criterion is using the specific energy, i.e. the energy per unit volume consumed in forming each material, using the different lubricants to produce the same reduction in height percentage of identical specimens from each of the two materials, namely: aluminum and brass. It was found that the super plastic tin-lead alloy lubricant has produced higher values of reductions in height percentage and less barreling in the two non-ferrous materials, used in this work namely: aluminum and brass. It was found that the super plastic tin-lead alloy lubricant has produced higher values of reductions in height percentage and less barreling in the two non-ferrous materials, used in this work, under the same compression force among the different used lubricants.

Keywords: aluminum, brass, different lubricants, free upsetting, solid lubricants, superplastic tin-lead alloy

Procedia PDF Downloads 465
4752 Surfactant-Free O/W-Emulsion as Drug Delivery System

Authors: M. Kumpugdee-Vollrath, J.-P. Krause, S. Bürk

Abstract:

Most of the drugs used for pharmaceutical purposes are poorly water-soluble drugs. About 40% of all newly discovered drugs are lipophilic and the numbers of lipophilic drugs seem to increase more and more. Drug delivery systems such as nanoparticles, micelles or liposomes are applied to improve their solubility and thus their bioavailability. Besides various techniques of solubilization, oil-in-water emulsions are often used to incorporate lipophilic drugs into the oil phase. To stabilize emulsions surface active substances (surfactants) are generally used. An alternative method to avoid the application of surfactants was of great interest. One possibility is to develop O/W-emulsion without any addition of surface active agents or the so called “surfactant-free emulsion or SFE”. The aim of this study was to develop and characterize SFE as a drug carrier by varying the production conditions. Lidocaine base was used as a model drug. The injection method was developed. Effects of ultrasound as well as of temperature on the properties of the emulsion were studied. Particle sizes and release were determined. The long-term stability up to 30 days was performed. The results showed that the surfactant-free O/W emulsions with pharmaceutical oil as drug carrier can be produced.

Keywords: emulsion, lidocaine, Miglyol, size, surfactant, light scattering, release, injection, ultrasound, stability

Procedia PDF Downloads 488
4751 Application of Machine Learning Models to Predict Couchsurfers on Free Homestay Platform Couchsurfing

Authors: Yuanxiang Miao

Abstract:

Couchsurfing is a free homestay and social networking service accessible via the website and mobile app. Couchsurfers can directly request free accommodations from others and receive offers from each other. However, it is typically difficult for people to make a decision that accepts or declines a request when they receive it from Couchsurfers because they do not know each other at all. People are expected to meet up with some Couchsurfers who are kind, generous, and interesting while it is unavoidable to meet up with someone unfriendly. This paper utilized classification algorithms of Machine Learning to help people to find out the Good Couchsurfers and Not Good Couchsurfers on the Couchsurfing website. By knowing the prior experience, like Couchsurfer’s profiles, the latest references, and other factors, it became possible to recognize what kind of the Couchsurfers, and furthermore, it helps people to make a decision that whether to host the Couchsurfers or not. The value of this research lies in a case study in Kyoto, Japan in where the author has hosted 54 Couchsurfers, and the author collected relevant data from the 54 Couchsurfers, finally build a model based on classification algorithms for people to predict Couchsurfers. Lastly, the author offered some feasible suggestions for future research.

Keywords: Couchsurfing, Couchsurfers prediction, classification algorithm, hospitality tourism platform, hospitality sciences, machine learning

Procedia PDF Downloads 133
4750 Variation of Lexical Choice and Changing Need of Identity Expression

Authors: Thapasya J., Rajesh Kumar

Abstract:

Language plays complex roles in society. The previous studies on language and society explain their interconnected, complementary and complex interactions and, those studies were primarily focused on the variations in the language. Variation being the fundamental nature of languages, the question of personal and social identity navigated through language variation and established that there is an interconnection between language variation and identity. This paper analyses the sociolinguistic variation in language at the lexical level and how the lexical choice of the speaker(s) affects in shaping their identity. It obtains primary data from the lexicon of the Mappila dialect of Malayalam spoken by the members of Mappila (Muslim) community of Kerala. The variation in the lexical choice is analysed by collecting data from the speech samples of 15 minutes from four different age groups of Mappila dialect speakers. Various contexts were analysed and the frequency of borrowed words in each instance is calculated to reach a conclusion on how the variation is happening in the speech community. The paper shows how the lexical choice of the speakers could be socially motivated and involve in shaping and changing identities. Lexical items or vocabulary clearly signal the group identity and personal identity. Mappila dialect of Malayalam was rich in frequent use of borrowed words from Arabic, Persian and Urdu. There was a deliberate attempt to show their identity as a Mappila community member, which was derived from the socio-political situation during those days. This made a clear variation between the Mappila dialect and other dialects of Malayalam at the surface level, which was motivated to create and establish the identity of a person as the member of Mappila community. Historically, these kinds of linguistic variation were highly motivated because of the socio-political factors and, intertwined with the historical facts about the origin and spread of Islamism in the region; people from the Mappila community highly motivated to project their identity as a Mappila because of the social insecurities they had to face before accepting that religion. Thus the deliberate inclusion of Arabic, Persian and Urdu words in their speech helped in showing their identity. However, the socio-political situations and factors at the origin of Mappila community have been changed over a period of time. The social motivation for indicating their identity as a Mappila no longer exist and thus the frequency of borrowed words from Arabic, Persian and Urdu have been reduced from their speech. Apart from the religious terms, the borrowed words from these languages are very few at present. The analysis is carried out by the changes in the language of the people according to their age and found to have significant variations between generations and literacy plays a major role in this variation process. The need of projecting a specific identity of an individual would vary according to the change in the socio-political scenario and a variation in language can shape the identity in order to go with the varying socio-political situation in any language.

Keywords: borrowings, dialect, identity, lexical choice, literacy, variation

Procedia PDF Downloads 239
4749 Prediction of the Torsional Vibration Characteristics of a Rotor-Shaft System Using Its Scale Model and Scaling Laws

Authors: Jia-Jang Wu

Abstract:

This paper presents the scaling laws that provide the criteria of geometry and dynamic similitude between the full-size rotor-shaft system and its scale model, and can be used to predict the torsional vibration characteristics of the full-size rotor-shaft system by manipulating the corresponding data of its scale model. The scaling factors, which play fundamental roles in predicting the geometry and dynamic relationships between the full-size rotor-shaft system and its scale model, for torsional free vibration problems between scale and full-size rotor-shaft systems are firstly obtained from the equation of motion of torsional free vibration. Then, the scaling factor of external force (i.e., torque) required for the torsional forced vibration problems is determined based on the Newton’s second law. Numerical results show that the torsional free and forced vibration characteristics of a full-size rotor-shaft system can be accurately predicted from those of its scale models by using the foregoing scaling factors. For this reason, it is believed that the presented approach will be significant for investigating the relevant phenomenon in the scale model tests.

Keywords: torsional vibration, full-size model, scale model, scaling laws

Procedia PDF Downloads 397
4748 Free and Open Source Licences, Software Programmers, and the Social Norm of Reciprocity

Authors: Luke McDonagh

Abstract:

Over the past three decades, free and open source software (FOSS) programmers have developed new, innovative and legally binding licences that have in turn enabled the creation of innumerable pieces of everyday software, including Linux, Mozilla Firefox and Open Office. That FOSS has been highly successful in competing with 'closed source software' (e.g. Microsoft Office) is now undeniable, but in noting this success, it is important to examine in detail why this system of FOSS has been so successful. One key reason is the existence of networks or communities of programmers, who are bound together by a key shared social norm of 'reciprocity'. At the same time, these FOSS networks are not unitary – they are highly diverse and there are large divergences of opinion between members regarding which licences are generally preferable: some members favour the flexible ‘free’ or 'no copyleft' licences, such as BSD and MIT, while other members favour the ‘strong open’ or 'strong copyleft' licences such as GPL. This paper argues that without both the existence of the shared norm of reciprocity and the diversity of licences, it is unlikely that the innovative legal framework provided by FOSS would have succeeded to the extent that it has.

Keywords: open source, copyright, licensing, copyleft

Procedia PDF Downloads 375
4747 Minorities and Soccer in the Middle East: Yelling From the Touchline

Authors: Saeb Farhan Al Ganideh

Abstract:

We draw on insights from theories of group threat and identity to explore how soccer rivalries can decode the relationship between ethnic minorities and local societies. How ethnic minorities used soccer, in the Arab countries of the Middle East, to express their racial-ethnic heritage is the main question that this paper grapples with at its most general level. The rhetoric around soccer and minorities in the Middle East show that ethnic minorities’ soccer clubs have faced varying degrees of discrimination. The paper relies on an analysis of 4 ethnic minorities’ soccer clubs, namely, Circassians in Jordan, Kurds in Syria, Sahrawis in Morocco, and Amazighs in Algeria, focusing on previous and current performance of these clubs. Ethnic minorities’ soccer clubs were the pinnacle in the Middle East region a few decades ago. Nonetheless, these soccer clubs, currently, fighting for not only their place in their countries’ local competitions but also for their existence as soccer clubs. Minorities’ soccer clubs have been plagued with challenges related to the change in political and social contexts in these countries.

Keywords: minorities, rivalries, soccer, middle east

Procedia PDF Downloads 522
4746 Free-Standing Pd-Based Metallic Glass Membranes for MEMS Applications

Authors: Wei-Shan Wang, Klaus Vogel, Felix Gabler, Maik Wiemer, Thomas Gessner

Abstract:

Metallic glasses, which are free of grain boundaries, have superior properties including large elastic limits, high strength, and excellent wear and corrosion resistance. Therefore, bulk metallic glasses (BMG) and thin film metallic glasses (TFMG) have been widely developed and investigated. Among various kinds of metallic glasses, Pd-Cu-Si TFMG, which has lower elastic modulus and better resistance of oxidation and corrosions compared to Zr- and Fe-based TFMGs, can be a promising candidate for MEMS applications. However, the study of Pd-TFMG membrane is still limited. This paper presents free-standing Pd-based metallic glass membranes with large area fabricated on wafer level for the first time. Properties of Pd-Cu-Si thin film metallic glass (TFMG) with various deposition parameters are investigated first. When deposited at 25°C, compressive stress occurs in the Pd76Cu6Si18 thin film regardless of Ar pressure. When substrate temperature is increased to 275°C, the stress state changes from compressive to tensile. Thin film stresses are slightly decreased when Ar pressure is higher. To show the influence of temperature on Pd-TFMGs, thin films without and with post annealing below (275°C) and within (370°C) supercooled liquid region are investigated. Results of XRD and TEM analysis indicate that Pd-TFMGs remain amorphous structure with well-controlled parameters. After verification of amorphous structure of the Pd-TFMGs, free-standing Pd-Cu-Si membranes were fabricated by depositing Pd-Cu-Si thin films directly on 200nm-thick silicon nitride membranes, followed by post annealing and dry etching of silicon nitride layer. Post annealing before SiNx removal is used to further release internal stress of Pd-TFMGs. The edge length of the square membrane ranges from 5 to 8mm. The effect of post annealing on Pd-Cu-Si membranes are discussed as well. With annealing at 370°C for 5 min, Pd-MG membranes are fully distortion-free after removal of SiNx layer. Results show that, by introducing annealing process, the stress-relief, distortion-free Pd-TFMG membranes with large area can be a promising candidate for sensing applications such as pressure and gas sensors.

Keywords: amorphous alloy, annealing, metallic glasses, TFMG membrane

Procedia PDF Downloads 352
4745 Impact of Flexibility on Residential Buildings in Egypt

Authors: Aly Mohamed El Husseiny, Azza Ezz Abdelkader

Abstract:

There is a critical thin line between freedom of choice and randomness. The distance between imagination and perception and between perception and execution varies depending on numerous factors. While in developed areas residents have the opportunity and abilities to build flexible homes, residents in developing areas create their own dwellings in informal settlements, even though none of them is comfortable at home in the long run. This paper explores three factors: What residents really need, what they do with limited flexibility, and what they do when there are no limits, as in the case of informal settlements. This paper studies alteration to residential buildings and how they connect to the changes in people’s lifecycle in all past cases. This study also examines all approaches to flexibility, focusing on a social approach. The results of this study are based on three practical studies: Interviews with residents in an informal settlement (Eshash Mahfouz in Minya in Egypt), a civil study of buildings in a middle-class district, and a survey of residents from many countries, including Egypt, and interviews with a number of them to determine residents’ needs and the extent of renovations they made or would like to make to their homes.

Keywords: flexibility, housing, freedom of choice, social, changes, residents

Procedia PDF Downloads 301
4744 Educational Credit in Enhancing Collaboration between Universities and Companies in Smart City

Authors: Eneken Titov, Ly Hobe

Abstract:

The collaboration between the universities and companies has been a challenging topic for many years, and although we have many good experiences, those seem to be single examples between one university and company. In Ülemiste Smart City in Estonia, the new initiative was started in 2020 fall, when five Estonian universities cooperated, led by the Ülemiste City developing company Mainor, intending to provide charge-free university courses for the Ülemiste City companies and their employees to encourage university-company wider collaboration. Every Ülemiste City company gets a certain number of free educational credit hours per year to participate in university courses. A functional and simple web platform was developed to mediate university courses for the companies. From January 2021, the education credit platform is open for all Ülemiste City companies and their employees to join, and universities offer more than 9000 hours of courses (appr 150 ECTS). Just two months later, more than 20% of Ülemiste City companies (82 out of 400) have joined the project, and their employees have registered for more than in total 3000 hours courses. The first results already show that the project supports the university marketing and the continuous education mindset in general, whether 1/4 of the courses are paid courses (e.g., when the company is out of free credit).

Keywords: education, educational credit, smart city, university-industry collaboration

Procedia PDF Downloads 204
4743 Electrical and Piezoelectric Properties of Vanadium-Modified Lead-Free (K₀.₅Na₀.₅)NbO₃ Ceramics

Authors: Radhapiyari Laishram, Chongtham Jiten, K. Chandramani Singh

Abstract:

During the last decade, there has been a significant growth in developing lead-free piezoelectric ceramics which have the potential to replace the currently dominant but highly superior lead-based piezoelectric materials such as PZT. Among the lead-free piezoelectrics, (K0.5Na0.5)NbO3 - based piezoceramics are promising candidates due to their superior piezoelectric properties and high Curie temperatures. In this work, (K0.5Na0.5)(Nb1-xVx)O3 powders with x varying the range 0 to 0.05 were synthesized from the raw materials K2CO3, Na2CO3, Nb2O5, and V2O5. These powders were ball milled with high-energy Retsch PM 100 ball mill using isopropanol as the medium at the speed of 200rpm for a duration of 8h. The milled powders were sintered at 1080oC for 1h. The crystalline phase of all the calcined powders and corresponding ceramics prepared was found to be perovskite with orthorhombic symmetry. The ceramic with V5+ content of x=0.03 exhibits the maximum values in density of 4.292 g/cc, room temperature dielectric constant (εr) of 432, and piezoelectric charge constant (d33) of 93pC/N. For this sample, the dielectric tan δ loss remains relatively low over a wide temperature range. The temperature dependence of P-E hysteresis loops has been investigated for the ceramic composition with x = 0.03.

Keywords: dielectric properties, ferroelectric properties, perovskie, piezoelectric properties

Procedia PDF Downloads 336
4742 Development of a Quick On-Site Pass/Fail Test for the Evaluation of Fresh Concrete Destined for Application as Exposed Concrete

Authors: Laura Kupers, Julie Piérard, Niki Cauberg

Abstract:

The use of exposed concrete (sometimes referred to as architectural concrete), keeps gaining popularity. Exposed concrete has the advantage to combine the structural properties of concrete with an aesthetic finish. However, for a successful aesthetic finish, much attention needs to be paid to the execution (formwork, release agent, curing, weather conditions…), the concrete composition (choice of the raw materials and mix proportions) as well as to its fresh properties. For the latter, a simple on-site pass/fail test could halt the casting of concrete not suitable for architectural concrete and thus avoid expensive repairs later. When architects opt for an exposed concrete, they usually want a smooth, uniform and nearly blemish-free surface. For this choice, a standard ‘construction’ concrete does not suffice. An aesthetic surface finishing requires the concrete to contain a minimum content of fines to minimize the risk of segregation and to allow complete filling of more complex shaped formworks. The concrete may neither be too viscous as this makes it more difficult to compact and it increases the risk of blow holes blemishing the surface. On the other hand, too much bleeding may cause color differences on the concrete surface. An easy pass/fail test, which can be performed on the site just before the casting, could avoid these problems. In case the fresh concrete fails the test, the concrete can be rejected. Only in case the fresh concrete passes the test, the concrete would be cast. The pass/fail tests are intended for a concrete with a consistency class S4. Five tests were selected as possible onsite pass/fail test. Two of these tests already exist: the K-slump test (ASTM C1362) and the Bauer Filter Press Test. The remaining three tests were developed by the BBRI in order to test the segregation resistance of fresh concrete on site: the ‘dynamic sieve stability test’, the ‘inverted cone test’ and an adapted ‘visual stability index’ (VSI) for the slump and flow test. These tests were inspired by existing tests for self-compacting concrete, for which the segregation resistance is of great importance. The suitability of the fresh concrete mixtures was also tested by means of a laboratory reference test (resistance to segregation) and by visual inspection (blow holes, structure…) of small test walls. More than fifteen concrete mixtures of different quality were tested. The results of the pass/fail tests were compared with the results of this laboratory reference test and the test walls. The preliminary laboratory results indicate that concrete mixtures ‘suitable’ for placing as exposed concrete (containing sufficient fines, a balanced grading curve etc.) can be distinguished from ‘inferior’ concrete mixtures. Additional laboratory tests, as well as tests on site, will be conducted to confirm these preliminary results and to set appropriate pass/fail values.

Keywords: exposed concrete, testing fresh concrete, segregation resistance, bleeding, consistency

Procedia PDF Downloads 425
4741 The Role of Social Parameters in the Choice of Address Forms Used in Kinship Domain in Punjab, Pakistan

Authors: Ana Ramsha, Samrah Hidayat

Abstract:

This study examines the role of social parameters in the choice of address forms used in kinship domain in Punjab, Pakistan. The study targeted 140 respondents in order to test the impact of social factors along with the regional differences in the choices of address forms in kinship domain. Statistical analyses are done by applying t-test for gender in relation to choices of address forms and ANOVA for age, income, education and social class. The study finds out that there is a strong connection of different social parameters not only with language use and practice but also in choices and use of address forms, especially in kinship relationships. Moreover, it is highlighted that gender does not influence in the choices of address forms, even the participants belonging to young and middle categories show no significant difference with regard to the choices of address form despite the fact that all the factors and parameters exert influence on the choices of address forms. Hence address forms as being one of the major traits of language and society is affected by all the social factors around and regional differences are also most important as they give identity and ethnicity to the society.

Keywords: address forms, kinship, social parameters, linguistics

Procedia PDF Downloads 133
4740 A Chemical-Free Colouration Technique for Regenerated Fibres Using Waste Alpaca Fibres

Authors: M. Abdullah Al Faruque, Rechana Remadevi, Abu Naser M. Ahsanul Haque, Joselito Razal, Xungai Wang, Maryam Naebe

Abstract:

Generally, the colouration of textile fibres is performed by using synthetic colourants in dope dyeing or conventional dyeing methods. However, the toxic effect of some synthetic colorants due to long-term exposure can cause several health threats including cancer, asthma and skin diseases. Moreover, in colouration process, these colourants not only consume a massive amount of water but also generates huge proportion of wastewater to the environment. Despite having the environmentally friendly characteristics, current natural colourants have downsides in their yield and need chemical extraction processes which are water consuming as well. In view of this, the present work focuses to develop a chemical-free biocompatible and natural pigment based colouration technique to colour regenerated fibres. Waste alpaca fibre was used as a colourant and the colour properties, as well as the mechanical properties, of the regenerated fibres were investigated. The colourant from waste alpaca was fabricated through mechanical milling process and it was directly applied to the polyacrylonitrile (PAN) dope solution in different ratios of alpaca: PAN (10:90, 20:80, 30:70). The results obtained from the chemical structure characterization suggested that all the coloured regenerated fibres exhibited chemical functional groups of both PAN and alpaca. Furthermore, the color strength was increased gradually with the increment of alpaca content and showed excellent washing fastness properties. These results reveal a potential new pathway for chemical-free dyeing technique for fibres with improved properties.

Keywords: alpaca, chemical-free coloration, natural colorant, polyacrylonitrile, water consumption, wet spinning

Procedia PDF Downloads 172
4739 Towards Binder-Free and Self Supporting Flexible Supercapacitor from Carbon Nano-Onions and Their Composite with CuO Nanoparticles

Authors: Debananda Mohapatra, Subramanya Badrayyana, Smrutiranjan Parida

Abstract:

Recognizing the upcoming era of carbon nanostructures and their revolutionary applications, we investigated the formation and supercapacitor application of highly pure and hydrophilic carbon nano-onions (CNOs) by economical one-step flame-synthesis procedure. The facile and scalable method uses easily available organic carbon source such as clarified butter, restricting the use of any catalyst, sophisticated instrumentation, high vacuum and post processing purification procedure. The active material was conformally coated onto a locally available cotton wipe by “sonicating and drying” process to obtain novel, lightweight, inexpensive, flexible, binder-free electrodes with strong adhesion between nanoparticles and porous wipe. This interesting electrode with CNO as the active material delivers a specific capacitance of 102.16 F/g, the energy density of 14.18 Wh/kg and power density of 2448 W/kg which are the highest values reported so far in symmetrical two electrode cell configuration with 1M Na2SO4 as an electrolyte. Incorporation of CuO nanoparticles to these functionalized CNOs by one-step hydrothermal method add up to a significant specific capacitance of 420 F/g with deliverable energy and power density at 58.33 Wh/kg and 4228 W/kg, respectively. The free standing CNOs, as well as CNO-CuO composite electrode, showed an excellent cyclic performance and stability retaining 95 and 90% initial capacitance even after 5000 charge-discharge cycles at a current density of 5 A/g. This work presents a new platform for high performance supercapacitors for next generation wearable electronic devices.

Keywords: binder-free, flame synthesis, flexible, carbon nano-onion

Procedia PDF Downloads 198
4738 Linguistic Codes: Food as a Class Indicator

Authors: Elena Valeryevna Pozhidaeva

Abstract:

This linguistic case study is based on an interaction between the social position and foodways. In every culture there is a social hierarchical system in which there can be means to express and to identify the social status of a person. Food serves as a class indicator. The British being a verbal nation use the words as a preferred medium for signalling and recognising the social status. The linguistic analysis reflects a symbolic hierarchy determined by social groups in the UK. The linguistic class indicators of a British hierarchical system are detectable directly – in speech acts. They are articulated in every aspect of a national identity’s life from preferences of the food and the choice to call it to the names of the meals. The linguistic class indicators can as well be detected indirectly – through symbolic meaning or via the choice of the mealtime, its class (e.g the classes of tea or marmalade), the place to buy food (the class of the supermarket) and consume it (the places for eating out and the frequency of such practices). Under analysis of this study are not only food items and their names but also such categories as cutlery as a class indicator and the act of eating together as a practice of social significance and a class indicator. Current social changes and economic developments are considered and their influence on the class indicators appearance and transformation.

Keywords: linguistic, class, social indicator, English, food class

Procedia PDF Downloads 404
4737 The Initiation of Privatization, Market Structure, and Free Entry with Vertically Related Markets

Authors: Hung-Yi Chen, Shih-Jye Wu

Abstract:

The existing literature provides little discussion on why a public monopolist gives up its market dominant position and allows private firms entering the market. We argue that the privatization of a public monopolist under a vertically related market may induce the entry of private firms. We develop a model of a mixed oligopoly with vertically related markets to explain the change in the market from a public monopolist to a mixed oligopoly and examine issues on privatizing the downstream public enterprise both in the short run and long run in the vertically related markets. We first show that the welfare-maximizing public monopoly firm is suboptimal in the vertically related markets. This is due to the fact that the privatization will reduce the input price charged by the upstream foreign monopolist. Further, the privatization will induce the entry of private firms since input price will decrease after privatization. Third, we demonstrate that the complete privatizing the public firm becomes a possible solution if the entry cost of private firm is low. Finally, we indicate that the public firm should partially privatize if the free-entry of private firms is allowed. JEL classification: F12, F14, L32, L33

Keywords: free entry, mixed oligopoly, public monopoly, the initiation of privatization, vertically related markets, mixed oligopoly

Procedia PDF Downloads 138
4736 Numerical Modeling of Large Scale Dam Break Flows

Authors: Amanbek Jainakov, Abdikerim Kurbanaliev

Abstract:

The work presents the results of mathematical modeling of large-scale flows in areas with a complex topographic relief. The Reynolds-averaged Navier—Stokes equations constitute the basis of the three-dimensional unsteady modeling. The well-known Volume of Fluid method implemented in the solver interFoam of the open package OpenFOAM 2.3 is used to track the free-boundary location. The mathematical model adequacy is checked by comparing with experimental data. The efficiency of the applied technology is illustrated by the example of modeling the breakthrough of the dams of the Andijan (Uzbekistan) and Papan (near the Osh town, Kyrgyzstan) reservoir.

Keywords: three-dimensional modeling, free boundary, the volume-of-fluid method, dam break, flood, OpenFOAM

Procedia PDF Downloads 405
4735 The Misuse of Free Cash and Earnings Management: An Analysis of the Extent to Which Board Tenure Mitigates Earnings Management

Authors: Michael McCann

Abstract:

Managerial theories propose that, in joint stock companies, executives may be tempted to waste excess free cash on unprofitable projects to keep control of resources. In order to conceal their projects' poor performance, they may seek to engage in earnings management. On the one hand, managers may manipulate earnings upwards in order to post ‘good’ performances and safeguard their position. On the other, since managers pursuit of unrewarding investments are likely to lead to low long-term profitability, managers will use negative accruals to reduce current year’s earnings, smoothing earnings over time in order to conceal the negative effects. Agency models argue that boards of directors are delegated by shareholders to ensure that companies are governed properly. Part of that responsibility is ensuring the reliability of financial information. Analyses of the impact of board characteristics, particularly board independence on the misuse of free cash flow and earnings management finds conflicting evidence. However, existing characterizations of board independence do not account for such directors gaining firm-specific knowledge over time, influencing their monitoring ability. Further, there is little analysis of the influence of the relative experience of independent directors and executives on decisions surrounding the use of free cash. This paper contributes to this literature regarding the heterogeneous characteristics of boards by investigating the influence of independent director tenure on earnings management and the relative tenures of independent directors and Chief Executives. A balanced panel dataset comprising 51 companies across 11 annual periods from 2005 to 2015 is used for the analysis. In each annual period, firms were classified as conducting earnings management if they had discretionary accruals in the bottom quartile (downwards) and top quartile (upwards) of the distributed values for the sample. Logistical regressions were conducted to determine the marginal impact of independent board tenure and a number of control variables on the probability of conducting earnings management. The findings indicate that both absolute and relative measures of board independence and experience do not have a significant impact on the likelihood of earnings management. It is the level of free cash flow which is the major influence on the probability of earnings management. Higher free cash flow increases the probability of earnings management significantly. The research also investigates whether board monitoring of earnings management is contingent on the level of free cash flow. However, the results suggest that board monitoring is not amplified when free cash flow is higher. This suggests that the extent of earnings management in companies is determined by a range of company, industry and situation-specific factors.

Keywords: corporate governance, boards of directors, agency theory, earnings management

Procedia PDF Downloads 236