Search results for: real time kinematics
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 20517

Search results for: real time kinematics

9867 Optimization of Biodiesel Production from Sunflower Oil Using Central Composite Design

Authors: Pascal Mwenge, Jefrey Pilusa, Tumisang Seodigeng

Abstract:

The current study investigated the effect of catalyst ratio and methanol to oil ratio on biodiesel production by using central composite design. Biodiesel was produced by transesterification using sodium hydroxide as a homogeneous catalyst, a laboratory scale reactor consisting of flat bottom flask mounts with a reflux condenser, and a heating plate was used to produce biodiesel. Key parameters, including time, temperature, and mixing rate was kept constant at 60 minutes, 60 oC and 600 RPM, respectively. From the results obtained, it was observed that the biodiesel yield depends on catalyst ratio and methanol to oil ratio. The highest yield of 50.65% was obtained at catalyst ratio of 0.5 wt.% and methanol to oil mole ratio 10.5. The analysis of variances of biodiesel yield showed the R Squared value of 0.8387. A quadratic mathematical model was developed to predict the biodiesel yield in the specified parameters ranges.

Keywords: ANOVA, biodiesel, catalyst, transesterification, central composite design

Procedia PDF Downloads 137
9866 A Performance Study of Fixed, Single-Axis and Dual-Axis Photovoltaic Systems in Kuwait

Authors: A. Al-Rashidi, A. El-Hamalawi

Abstract:

In this paper, a performance study was conducted to investigate single and dual-axis PV systems to generate electricity in five different sites in Kuwait. Relevant data were obtained by using two sources for validation purposes. A commercial software, PVsyst, was used to analyse the data, such as metrological data and other input parameters, and compute the performance parameters such as capacity factor (CF) and final yield (YF). The results indicated that single and dual-axis PV systems would be very beneficial to electricity generation in Kuwait as an alternative source to conventional power plants, especially with the increased demand over time. The ranges were also found to be competitive in comparison to leading countries using similar systems. A significant increase in CF and YF values around 24% and 28.8% was achieved related to the use of single and dual systems, respectively.

Keywords: single-axis and dual-axis photovoltaic systems, capacity factor, final yield, Kuwait

Procedia PDF Downloads 290
9865 The Reflection of Greek Reality Concerning Taxation from the Perspective of Both Tax Payers and Taxmen

Authors: Evagelia Makri, Maria Tsourela, Dimitris Paschaloudis, Dafni M. Nerantzaki

Abstract:

One of the biggest financial and social problems, which at the same time constitute one of the greater challenges that Greek society faces today, is the illegal avoidance of tax payments. Tax evasion may negate financial data and community budgets, as well as breed financial chaos. This research seeks to reflect Greek reality concerning tax measures. Also, there will be an effort to record the factors surrounding tax evasion. Greek tax system’s data will be rendered in financial terms. Questionnaires will be handed out to tax payers, and interviews will be conducted to taxmen. The quantitative analysis of the questionnaire answers will define the tax payers’ opinion towards the existence of tax evasion. The qualitative analysis of the interviews will reveal the main reason that boosts tax evasion. At the end, there will be some realistic proposals about how to better collect taxes, through the creation of a strong regulatory mechanism.

Keywords: tax evasion, tax collection measures, insurance recovery measures, Greek tax system

Procedia PDF Downloads 356
9864 A Study on the Health Intervention Mechanism of Built Environment in Urban Parks under the Perspective of Stress Adjustment

Authors: Ruoyu Mao

Abstract:

The fast-paced and high-stress lifestyle of modern cities is an important cause of mental health problems and chronic physical diseases, and at the same time, all kinds of health problems will react to physical and mental stress, further aggravating the health risks; therefore, stress adjustment should be considered as an important perspective of the spatial environment to intervene in the health of the population. The purpose of this paper is to analyse the structural and therapeutic characteristics of the built environment of urban parks, to analyse the path of its effect on the stress adjustment of the population, and to summarise the mechanism of the built environment of urban parks to intervene in the health of the population from the perspective of stress adjustment.

Keywords: stress adjustment, health interventions, urban parks, built environments

Procedia PDF Downloads 38
9863 Ageing Population and Generational Turn-Over in the Italian Labour Market: Towards a Sustainable Solidarity

Authors: Marianna Russo

Abstract:

Ageing population and youth unemployment are the major challenges that Western Countries – and Italy in particular – are facing in recent years. These phenomena have a significant impact not only on the labour market and the welfare system, but also on the organisational models of work. Therefore, in Italy, in the past few years, there have been some attempts to regulate the management of generational turn-over: intergenerational pacts, early retirement incentives, solidarity contracts, etc. In particular, this paper aims to focus on the expansive solidarity contracts, that were introduced in the Italian legal system for the first time in 1984. Indeed, they have been little used during the thirty years of their lives, so the Legislative Decree no. 148/2015, implementing the so-called Jobs Act, has given them another opportunity. The paper tries to analyse the rules and the empirical data, looking for a sustainable model of generational turn-over management.

Keywords: ageing population, generational turn-over, Italian jobs' act, solidarity contracts

Procedia PDF Downloads 250
9862 Propellant Less Propulsion System Using Microwave Thrusters

Authors: D. Pradeep Mitra, Prafulla

Abstract:

Looking to the word propellant-less system it makes us to believe that it is an impossible one, but this paper demonstrates the use of microwaves to create a system which makes impossible to be possible, it means a propellant-less propulsion system using microwaves. In these thrusters, microwaves are radiated into a sealed parabolic cavity through a waveguide, which act on the surface of the cavity and follow the axis of the thrusters to produce thrust. The advantages of these thrusters are: (1) Producing thrust without propellant; without erosion, wear, and thermal stress from the hot exhaust gas; and at the same time increasing quality. (2) If the microwave output power is stable, the performance of thrusters is not affected by its working environment. This paper is demonstrated from general maxwell equations. These equations are used to create the mathematical model of the thrusters. These mathematical model helps us to calculate the Q factor and calculate the approximate thrust which would be generated in the system.

Keywords: propellant less, microwaves, parabolic wave guide, propulsion system

Procedia PDF Downloads 375
9861 Development of Visual Element Design Guidelines for Consumer Products Based on User Characteristics

Authors: Taezoon Park, Wonil Hwang

Abstract:

This study aims to build a design guideline for the effective visual display used for consumer products considering user characteristics; gender and age. Although a number of basic experiments identified the limits of human visual perception, the findings remain fragmented and many times in an unfriendly form. This study compiled a design cases along with tables aggregated from the experimental result of visual perception; brightness/contrast, useful field of view, color sensitivity. Visual design elements commonly used for consumer product, were selected and appropriate guidelines were developed based on the experimental result. Since the provided data with case example suggests a feasible design space, it will save time for a product designer to find appropriate design alternatives.

Keywords: design guideline, consumer product, visual design element, visual perception, emotional design

Procedia PDF Downloads 362
9860 Component Lifecycle and Concurrency Model in Usage Control (UCON) System

Authors: P. Ghann, J. Shiguang, C. Zhou

Abstract:

Access control is one of the most challenging issues facing information security. Access control is defined as, the ability to permit or deny access to a particular computational resource or digital information by an unauthorized user or subject. The concept of usage control (UCON) has been introduced as a unified approach to capture a number of extensions for access control models and systems. In UCON, an access decision is determined by three factors: Authorizations, obligations and conditions. Attribute mutability and decision continuity are two distinct characteristics introduced by UCON for the first time. An observation of UCON components indicates that, the components are predefined and static. In this paper, we propose a new and flexible model of usage control for the creation and elimination of some of these components; for example new objects, subjects, attributes and integrate these with the original UCON model. We also propose a model for concurrent usage scenarios in UCON.

Keywords: access control, concurrency, digital container, usage control

Procedia PDF Downloads 315
9859 Method for Requirements Analysis and Decision Making for Restructuring Projects in Factories

Authors: Rene Hellmuth

Abstract:

The requirements for the factory planning and the building concerned have changed in the last years. Factory planning has the task of designing products, plants, processes, organization, areas, and the building of a factory. Regular restructuring gains more importance in order to maintain the competitiveness of a factory. Restrictions regarding new areas, shorter life cycles of product and production technology as well as a VUCA (volatility, uncertainty, complexity and ambiguity) world cause more frequently occurring rebuilding measures within a factory. Restructuring of factories is the most common planning case today. Restructuring is more common than new construction, revitalization and dismantling of factories. The increasing importance of restructuring processes shows that the ability to change was and is a promising concept for the reaction of companies to permanently changing conditions. The factory building is the basis for most changes within a factory. If an adaptation of a construction project (factory) is necessary, the inventory documents must be checked and often time-consuming planning of the adaptation must take place to define the relevant components to be adapted, in order to be able to finally evaluate them. The different requirements of the planning participants from the disciplines of factory planning (production planner, logistics planner, automation planner) and industrial construction planning (architect, civil engineer) come together during reconstruction and must be structured. This raises the research question: Which requirements do the disciplines involved in the reconstruction planning place on a digital factory model? A subordinate research question is: How can model-based decision support be provided for a more efficient design of the conversion within a factory? Because of the high adaptation rate of factories and its building described above, a methodology for rescheduling factories based on the requirements engineering method from software development is conceived and designed for practical application in factory restructuring projects. The explorative research procedure according to Kubicek is applied. Explorative research is suitable if the practical usability of the research results has priority. Furthermore, it will be shown how to best use a digital factory model in practice. The focus will be on mobile applications to meet the needs of factory planners on site. An augmented reality (AR) application will be designed and created to provide decision support for planning variants. The aim is to contribute to a shortening of the planning process and model-based decision support for more efficient change management. This requires the application of a methodology that reduces the deficits of the existing approaches. The time and cost expenditure are represented in the AR tablet solution based on a building information model (BIM). Overall, the requirements of those involved in the planning process for a digital factory model in the case of restructuring within a factory are thus first determined in a structured manner. The results are then applied and transferred to a construction site solution based on augmented reality.

Keywords: augmented reality, digital factory model, factory planning, restructuring

Procedia PDF Downloads 123
9858 Intelligent Indoor Localization Using WLAN Fingerprinting

Authors: Gideon C. Joseph

Abstract:

The ability to localize mobile devices is quite important, as some applications may require location information of these devices to operate or deliver better services to the users. Although there are several ways of acquiring location data of mobile devices, the WLAN fingerprinting approach has been considered in this work. This approach uses the Received Signal Strength Indicator (RSSI) measurement as a function of the position of the mobile device. RSSI is a quantitative technique of describing the radio frequency power carried by a signal. RSSI may be used to determine RF link quality and is very useful in dense traffic scenarios where interference is of major concern, for example, indoor environments. This research aims to design a system that can predict the location of a mobile device, when supplied with the mobile’s RSSIs. The developed system takes as input the RSSIs relating to the mobile device, and outputs parameters that describe the location of the device such as the longitude, latitude, floor, and building. The relationship between the Received Signal Strengths (RSSs) of mobile devices and their corresponding locations is meant to be modelled; hence, subsequent locations of mobile devices can be predicted using the developed model. It is obvious that describing mathematical relationships between the RSSIs measurements and localization parameters is one option to modelling the problem, but the complexity of such an approach is a serious turn-off. In contrast, we propose an intelligent system that can learn the mapping of such RSSIs measurements to the localization parameters to be predicted. The system is capable of upgrading its performance as more experiential knowledge is acquired. The most appealing consideration to using such a system for this task is that complicated mathematical analysis and theoretical frameworks are excluded or not needed; the intelligent system on its own learns the underlying relationship in the supplied data (RSSI levels) that corresponds to the localization parameters. These localization parameters to be predicted are of two different tasks: Longitude and latitude of mobile devices are real values (regression problem), while the floor and building of the mobile devices are of integer values or categorical (classification problem). This research work presents artificial neural network based intelligent systems to model the relationship between the RSSIs predictors and the mobile device localization parameters. The designed systems were trained and validated on the collected WLAN fingerprint database. The trained networks were then tested with another supplied database to obtain the performance of trained systems on achieved Mean Absolute Error (MAE) and error rates for the regression and classification tasks involved therein.

Keywords: indoor localization, WLAN fingerprinting, neural networks, classification, regression

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9857 Capacity Estimation of Hybrid Automated Repeat Request Protocol for Low Earth Orbit Mega-Constellations

Authors: Arif Armagan Gozutok, Alper Kule, Burak Tos, Selman Demirel

Abstract:

Wireless communication chain requires effective ways to keep throughput efficiency high while it suffers location-dependent, time-varying burst errors. Several techniques are developed in order to assure that the receiver recovers the transmitted information without errors. The most fundamental approaches are error checking and correction besides re-transmission of the non-acknowledged packets. In this paper, stop & wait (SAW) and chase combined (CC) hybrid automated repeat request (HARQ) protocols are compared and analyzed in terms of throughput and average delay for the usage of low earth orbit (LEO) mega-constellations case. Several assumptions and technological implementations are considered as well as usage of low-density parity check (LDPC) codes together with several constellation orbit configurations.

Keywords: HARQ, LEO, satellite constellation, throughput

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9856 Influence of Some Parameters on Embryonic Mortality of Barbary Partridge Alectoris barbara in a Semi-Captive Breeding

Authors: H. Idouhar-Saadi, A. Smaï, S. Zenia, F. Haddadj, M. Aissi, S. Doumandji

Abstract:

During the period of reproduction, the collection of eggs of the Barbary gambra partridge is made only once a week in the morning, considering the sensibility in the stress of this native species. The number of considered samples is 33 eggs. The duration of the incubation is of 18 days. Unhatched eggs and eggs eliminated previously at the time of the mirage are collected and forwarded to the laboratories of microbiology and parasitology. The average weight of the eggs of the Barbary Partridge vary much [20.08 ± 1.81 g. (2006) < Pm < 20.82 ± 2,11g. (2008)]. The percentage of unhatched eggs varies between 9.3% in 2005 and 15.55% in 2007. It appears that the rate of embryonic mortality is slightly higher compared to that of infertile eggs. Microbiological analysis of unhatched eggs showed the presence of pathogenic germs such as lute Chryseomonas luteola. Chryseomonas ola and Escherichia coli. As against the parasites research is negative.

Keywords: barbary partridge, unhatched eggs, embryo mortality, pathogenic germs

Procedia PDF Downloads 528
9855 Working From Home: On the Relationship Between Place Attachment to Work Place, Extraversion and Segmentation Preference to Burnout

Authors: Diamant Irene, Shklarnik Batya

Abstract:

In on to its widespread effects on health and economic issues, Covid-19 shook the work and employment world. Among the prominent changes during the pandemic is the work-from-home trend, complete or partial, as part of social distancing. In fact, these changes accelerated an existing tendency of work flexibility already underway before the pandemic. Technology and means of advanced communications led to a re-assessment of “place of work” as a physical space in which work takes place. Today workers can remotely carry out meetings, manage projects, work in groups, and different research studies point to the fact that this type of work has no adverse effect on productivity. However, from the worker’s perspective, despite numerous advantages associated with work from home, such as convenience, flexibility, and autonomy, various drawbacks have been identified such as loneliness, reduction of commitment, home-work boundary erosion, all risk factors relating to the quality of life and burnout. Thus, a real need has arisen in exploring differences in work-from-home experiences and understanding the relationship between psychological characteristics and the prevalence of burnout. This understanding may be of significant value to organizations considering a future hybrid work model combining in-office and remote working. Based on Hobfoll’s Theory of Conservation of Resources, we hypothesized that burnout would mainly be found among workers whose physical remoteness from the workplace threatens or hinders their ability to retain significant individual resources. In the present study, we compared fully remote and partially remote workers (hybrid work), and we examined psychological characteristics and their connection to the formation of burnout. Based on the conceptualization of Place Attachment as the cognitive-emotional bond of an individual to a meaningful place and the need to maintain closeness to it, we assumed that individuals characterized with Place Attachment to the workplace would suffer more from burnout when working from home. We also assumed that extrovert individuals, characterized by the need of social interaction at the workplace and individuals with segmentationpreference – a need for separation between different life domains, would suffer more from burnout, especially among fully remote workers relative to partially remote workers. 194 workers, of which 111 worked from home in full and 83 worked partially from home, aged 19-53, from different sectors, were tested using an online questionnaire through social media. The results of the study supported our assumptions. The repercussions of these findings are discussed, relating to future occupational experience, with an emphasis on suitable occupational adjustment according to the psychological characteristics and needs of workers.

Keywords: working from home, burnout, place attachment, extraversion, segmentation preference, Covid-19

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9854 Intercultural Strategies of Chinese Composers in the Organizational Structure of Their Works

Authors: Bingqing Chen

Abstract:

The Opium War unlocked the gate of China. Since then, modern western culture has been imported strongly and spread throughout this Asian country. The monologue of traditional Chinese culture in the past has been replaced by the hustle and bustle of multiculturalism. In the field of music, starting from school music, China, a country without the concept of composition, was deeply influenced by western culture and professional music composition, and entered the era of professional music composition. Recognizing the importance of national culture, a group of insightful artists began to try to add ‘China’ to musical composition. However, due to the special historical origin of Chinese professional musical composition and the three times of cultural nihilism in China, professional musical composition at this time failed to interpret the deep language structure of local culture within Chinese traditional culture, but only regarded Chinese traditional music as a ‘melody material library.’ At this time, the cross-cultural composition still takes Western music as its ‘norm,’ while our own music culture only exists as the sound of the contrast of Western music. However, after reading scores extensively, watching video performances, and interviewing several active composers, we found that at least in the past 30 years, China has created some works that can be called intercultural music. In these kinds of music, composers put Chinese and Western, traditional and modern in an almost equal position to have a dialogue based on their deep understanding and respect for the two cultures. This kind of music connects two music worlds, and links the two cultural and ideological worlds behind it, and communicates and grows together. This paper chose the works of three composers with different educational backgrounds, and pay attention to how composers can make a dialogue at the organizational structure level of their works. Based on the strategies adopted by composers in structuring their works, this paper expounds on how the composer's music procedure shows intercultural in terms of whole sound effects and cultural symbols. By actively participating in this intercultural practice, composers resorting to various musical and extra-musical procedures to arrive at the so-called ‘innovation within tradition.’ Through the dialogue, we can activate the space of creative thinking and explore the potential contained in culture. This interdisciplinary research promotes the rethinking of the possibility of innovation in contemporary Chinese intercultural music composition, spanning the fields of sound studies, dialogue theory, cultural research, music theory, and so on. Recently, China is calling for actively promoting 'the construction of Chinese music canonization,’ expecting to form a particular music style to show national-cultural identity. In the era of globalization, it is possible to form a brand-new Chinese music style through intercultural composition, but it is a question about talents, and the key lies in how composers do it. There is no recipe for the formation of the Chinese music style, only the composers constantly trying and tries to solve problems in their works.

Keywords: dialogism, intercultural music, national-cultural identity, organization/structure, sound

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9853 Possibility of Making Ceramic Models from Condemned Plaster of Paris (Pop) Moulds for Ceramics Production in Edo State Nigeria

Authors: Osariyekemwen, Daniel Nosakhare

Abstract:

Some ceramic wastes, such as discarded (condemn) Plaster of Paris (POP) in Auchi Polytechnic, Edo State, constitute environmental hazards. This study, therefore, bridges the forgoing gaps by undertaking the use of these discarded (POP) moulds to produced ceramic models for making casting moulds for mass production. This is in line with the possibility of using this medium to properly manage the discarded (condemn) Plaster of Paris (POP) that littered our immediate environment. Presently these are major wastes disposal in the department. Hence, the study has been made to fabricate sanitary miniature models and contract fuse models, respectively. Findings arising from this study show that discarded (condemn) Plaster of Paris (POP) can be carved when to set it neither shrink nor expand; hence warping is quite unusual. Above all, it also gives good finishing with little deterioration with time when compared to clay models.

Keywords: plaster of Paris, condemn, moulds, models, production

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9852 Evolution of Memorial Architecture: Comparative Study of Aesthetics and Elements of Memorials in Europe and Indian Subcontinent

Authors: Madhusudan Hamirwasia, Sarang Barbarwar, Arshleen Kaur

Abstract:

The construction of memorials began thousands of years ago and the practice is still continuing. These memorials became a symbol to honor great people and events in the history. The aim of the study was to understand the evolution of memorials from an architectural design perspective. It is also concentrated on the similarities and differences between the memorials in Europe and those in the Indian subcontinent. The study shows how the design of a memorial has seen a considerable shift from the tribal Urasgattas to the contemporary commemorative structures. While they were somber symbolic gestures in the past, they have now transformed into a socio-cultural space in urban areas. Not only the memorials were inspired by the culture but the culture too got influenced by the memorials as with progressing time, they hold the vital link to our past. The study intends to encapsulate the essence of design elements in these memorials that convey the visitors the intangible messages held by the edifice in its tangible presence.

Keywords: evolution, emotion, memorials, symbolism

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9851 Utilization of Schnerr-Sauer Cavitation Model for Simulation of Cavitation Inception and Super Cavitation

Authors: Mohammadreza Nezamirad, Azadeh Yazdi, Sepideh Amirahmadian, Nasim Sabetpour, Amirmasoud Hamedi

Abstract:

In this study, the Reynolds-Stress-Navier-Stokes framework is utilized to investigate the flow inside the diesel injector nozzle. The flow is assumed to be multiphase as the formation of vapor by pressure drop is visualized. For pressure and velocity linkage, the coupled algorithm is used. Since the cavitation phenomenon inherently is unsteady, the quasi-steady approach is utilized for saving time and resources in the current study. Schnerr-Sauer cavitation model is used, which was capable of predicting flow behavior both at the initial and final steps of the cavitation process. Two different turbulent models were used in this study to clarify which one is more capable in predicting cavitation inception and super-cavitation. It was found that K-ε was more compatible with the Shnerr-Sauer cavitation model; therefore, the mentioned model is used for the rest of this study.

Keywords: CFD, RANS, cavitation, fuel, injector

Procedia PDF Downloads 201
9850 A Formal Verification Approach for Linux Kernel Designing

Authors: Zi Wang, Xinlei He, Jianghua Lv, Yuqing Lan

Abstract:

Kernel though widely used, is complicated. Errors caused by some bugs are often costly. Statically, more than half of the mistakes occur in the design phase. Thus, we introduce a modeling method, KMVM (Linux Kernel Modeling and verification Method), based on type theory for proper designation and correct exploitation of the Kernel. In the model, the Kernel is separated into six levels: subsystem, dentry, file, struct, func, and base. Each level is treated as a type. The types are specified in the structure and relationship. At the same time, we use a demanding path to express the function to be implemented. The correctness of the design is verified by recursively checking the type relationship and type existence. The method has been applied to verify the OPEN business of VFS (virtual file system) in Linux Kernel. Also, we have designed and developed a set of security communication mechanisms in the Kernel with verification.

Keywords: formal approach, type theory, Linux Kernel, software program

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9849 Optimal Relaxation Parameters for Obtaining Efficient Iterative Methods for the Solution of Electromagnetic Scattering Problems

Authors: Nadaniela Egidi, Pierluigi Maponi

Abstract:

The approximate solution of a time-harmonic electromagnetic scattering problem for inhomogeneous media is required in several application contexts, and its two-dimensional formulation is a Fredholm integral equation of the second kind. This integral equation provides a formulation for the direct scattering problem, but it has to be solved several times also in the numerical solution of the corresponding inverse scattering problem. The discretization of this Fredholm equation produces large and dense linear systems that are usually solved by iterative methods. In order to improve the efficiency of these iterative methods, we use the Symmetric SOR preconditioning, and we propose an algorithm for the evaluation of the associated relaxation parameter. We show the efficiency of the proposed algorithm by several numerical experiments, where we use two Krylov subspace methods, i.e., Bi-CGSTAB and GMRES.

Keywords: Fredholm integral equation, iterative method, preconditioning, scattering problem

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9848 Implementation of the Interlock Protocol to Enhance Security in Unmanned Aerial Vehicles

Authors: Vikram Prabhu, Mohammad Shikh Bahaei

Abstract:

This paper depicts the implementation of a new infallible technique to protect an Unmanned Aerial Vehicle from cyber-attacks. An Unmanned Aerial Vehicle (UAV) could be vulnerable to cyber-attacks because of jammers or eavesdroppers over the network which pose as a threat to the security of the UAV. In the field of network security, there are quite a few protocols which can be used to establish a secure connection between UAVs and their Operators. In this paper, we discuss how the Interlock Protocol could be implemented to foil the Man-in-the-Middle Attack. In this case, Wireshark has been used as the sniffer (man-in-the-middle). This paper also shows a comparison between the Interlock Protocol and the TCP Protocols using cryptcat and netcat and at the same time highlights why the Interlock Protocol is the most efficient security protocol to prevent eavesdropping over the communication channel.

Keywords: interlock protocol, Diffie-Hellman algorithm, unmanned aerial vehicles, control station, man-in-the-middle attack, Wireshark

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9847 Shared Vision System Support for Maintenance Tasks of Wind Turbines

Authors: Buket Celik Ünal, Onur Ünal

Abstract:

Communication is the most challenging part of maintenance operations. Communication between expert and fieldworker is crucial for effective maintenance and this also affects the safety of the fieldworkers. To support a machine user in a remote collaborative physical task, both, a mobile and a stationary device are needed. Such a system is called a shared vision system and the system supports two people to solve a problem from different places. This system reduces the errors and provides a reliable support for qualified and less qualified users. Through this research, it was aimed to validate the effectiveness of using a shared vision system to facilitate communication between on-site workers and those issuing instructions regarding maintenance or inspection works over long distances. The system is designed with head-worn display which is called a shared vision system. As a part of this study, a substitute system is used and implemented by using a shared vision system for maintenance operation. The benefits of the use of a shared vision system are analyzed and results are adapted to the wind turbines to improve the occupational safety and health for maintenance technicians. The motivation for the research effort in this study can be summarized in the following research questions: -How can expert support technician over long distances during maintenance operation? -What are the advantages of using a shared vision system? Experience from the experiment shows that using a shared vision system is an advantage for both electrical and mechanical system failures. Results support that the shared vision system can be used for wind turbine maintenance and repair tasks. Because wind turbine generator/gearbox and the substitute system have similar failures. Electrical failures, such as voltage irregularities, wiring failures and mechanical failures, such as alignment, vibration, over-speed conditions are the common and similar failures for both. Furthermore, it was analyzed the effectiveness of the shared vision system by using a smart glasses in connection with the maintenance task performed by a substitute system under four different circumstances, namely by using a shared vision system, an audio communication, a smartphone and by yourself condition. A suitable method for determining dependencies between factors measured in Chi Square Test, and Chi Square Test for Independence measured for determining a relationship between two qualitative variables and finally Mann Whitney U Test is used to compare any two data sets. While based on this experiment, no relation was found between the results and the gender. Participants` responses confirmed that the shared vision system is efficient and helpful for maintenance operations. From the results of the research, there was a statistically significant difference in the average time taken by subjects on works using a shared vision system under the other conditions. Additionally, this study confirmed that a shared vision system provides reduction in time to diagnose and resolve maintenance issues, reduction in diagnosis errors, reduced travel costs for experts, and increased reliability in service.

Keywords: communication support, maintenance and inspection tasks, occupational health and safety, shared vision system

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9846 Effect of Financial and Institutional Ecosystems on Startup Mergers and Acquisitions

Authors: Saurabh Ahluwalia, Sul Kassicieh

Abstract:

The conventional wisdom has maintained that being in proximity to entrepreneurial ecosystems helps startups to raise financing, develop and grow. In this paper, we examine the effect of a major component of an entrepreneurial ecosystem- financial or venture capital clusters on the exit of a startup through mergers and acquisitions (M&A). We find that the presence of a venture capitalist in a venture capital (VC) cluster is a major success factor for M&A exits. The location of startups in the top VC clusters did not turn out to be significant for success. Our results are robust to different specifications of the model that use different time periods, types of success, the reputation of VC, industry and the quality of the startup company. Our results provide evidence for VCs, startups and policymakers who want to better understand the components of entrepreneurial ecosystems and their relation to the M&A exits of startups.

Keywords: financial institution, mergers and acquisitions, startup financing, venture capital

Procedia PDF Downloads 190
9845 Restricted Boltzmann Machines and Deep Belief Nets for Market Basket Analysis: Statistical Performance and Managerial Implications

Authors: H. Hruschka

Abstract:

This paper presents the first comparison of the performance of the restricted Boltzmann machine and the deep belief net on binary market basket data relative to binary factor analysis and the two best-known topic models, namely Dirichlet allocation and the correlated topic model. This comparison shows that the restricted Boltzmann machine and the deep belief net are superior to both binary factor analysis and topic models. Managerial implications that differ between the investigated models are treated as well. The restricted Boltzmann machine is defined as joint Boltzmann distribution of hidden variables and observed variables (purchases). It comprises one layer of observed variables and one layer of hidden variables. Note that variables of the same layer are not connected. The comparison also includes deep belief nets with three layers. The first layer is a restricted Boltzmann machine based on category purchases. Hidden variables of the first layer are used as input variables by the second-layer restricted Boltzmann machine which then generates second-layer hidden variables. Finally, in the third layer hidden variables are related to purchases. A public data set is analyzed which contains one month of real-world point-of-sale transactions in a typical local grocery outlet. It consists of 9,835 market baskets referring to 169 product categories. This data set is randomly split into two halves. One half is used for estimation, the other serves as holdout data. Each model is evaluated by the log likelihood for the holdout data. Performance of the topic models is disappointing as the holdout log likelihood of the correlated topic model – which is better than Dirichlet allocation - is lower by more than 25,000 compared to the best binary factor analysis model. On the other hand, binary factor analysis on its own is clearly surpassed by both the restricted Boltzmann machine and the deep belief net whose holdout log likelihoods are higher by more than 23,000. Overall, the deep belief net performs best. We also interpret hidden variables discovered by binary factor analysis, the restricted Boltzmann machine and the deep belief net. Hidden variables characterized by the product categories to which they are related differ strongly between these three models. To derive managerial implications we assess the effect of promoting each category on total basket size, i.e., the number of purchased product categories, due to each category's interdependence with all the other categories. The investigated models lead to very different implications as they disagree about which categories are associated with higher basket size increases due to a promotion. Of course, recommendations based on better performing models should be preferred. The impressive performance advantages of the restricted Boltzmann machine and the deep belief net suggest continuing research by appropriate extensions. To include predictors, especially marketing variables such as price, seems to be an obvious next step. It might also be feasible to take a more detailed perspective by considering purchases of brands instead of purchases of product categories.

Keywords: binary factor analysis, deep belief net, market basket analysis, restricted Boltzmann machine, topic models

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9844 Multimodal Analysis of News Magazines' Front-Page Portrayals of the US, Germany, China, and Russia

Authors: Alena Radina

Abstract:

On the global stage, national image is shaped by historical memory of wars and alliances, government ideology and particularly media stereotypes which represent countries in positive or negative ways. News magazine covers are a key site for national representation. The object of analysis in this paper is the portrayals of the US, Germany, China, and Russia in the front pages and cover stories of “Time”, “Der Spiegel”, “Beijing Review”, and “Expert”. Political comedy helps people learn about current affairs even if politics is not their area of interest, and thus satire indirectly sets the public agenda. Coupled with satirical messages, cover images and the linguistic messages embedded in the covers become persuasive visual and verbal factors, known to drive about 80% of magazine sales. Preliminary analysis identified satirical elements in magazine covers, which are known to influence and frame understandings and attract younger audiences. Multimodal and transnational comparative framing analyses lay the groundwork to investigate why journalists, editors and designers deploy certain frames rather than others. This research investigates to what degree frames used in covers correlate with frames within the cover stories and what these framings can tell us about media professionals’ representations of their own and other nations. The study sample includes 32 covers consisting of two covers representing each of the four chosen countries from the four magazines. The sampling framework considers two time periods to compare countries’ representation with two different presidents, and between men and women when present. The countries selected for analysis represent each category of the international news flows model: the core nations are the US and Germany; China is a semi-peripheral country; and Russia is peripheral. Examining textual and visual design elements on the covers and images in the cover stories reveals not only what editors believe visually attracts the reader’s attention to the magazine but also how the magazines frame and construct national images and national leaders. The cover is the most powerful editorial and design page in a magazine because images incorporate less intrusive framing tools. Thus, covers require less cognitive effort of audiences who may therefore be more likely to accept the visual frame without question. Analysis of design and linguistic elements in magazine covers helps to understand how media outlets shape their audience’s perceptions and how magazines frame global issues. While previous multimodal research of covers has focused mostly on lifestyle magazines or newspapers, this paper examines the power of current affairs magazines’ covers to shape audience perception of national image.

Keywords: framing analysis, magazine covers, multimodality, national image, satire

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9843 Quintic Spline Method for Variable Coefficient Fourth-Order Parabolic Partial Differential Equations

Authors: Reza Mohammadi, Mahdieh Sahebi

Abstract:

We develop a method based on polynomial quintic spline for numerical solution of fourth-order non-homogeneous parabolic partial differential equation with variable coefficient. By using polynomial quintic spline in off-step points in space and finite difference in time directions, we obtained two three level implicit methods. Stability analysis of the presented method has been carried out. We solve four test problems numerically to validate the proposed derived method. Numerical comparison with other existence methods shows the superiority of our presented scheme.

Keywords: fourth-order parabolic equation, variable coefficient, polynomial quintic spline, off-step points, stability analysis

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9842 Female Tenderness in Children’s Literature: A Content Analysis of Gender Depiction in Greek Preschool Picture Books

Authors: Theopoula Karanikolaou

Abstract:

During recent decades an increasing number of studies indicate the negative impact of gender stereotypes in various aspects of society as well as in everyday life. At the same time, children’s literature is considered an important factor of gender-role socialization as it provides young readers with socially accepted gender behavioral models. Using a content analysis approach, this research examines the female representations in Greek children’s literature published from 2009 to 2019. Results indicate that female characters are depicted as sensitive and tender both in texts and illustrations, traits that are almost absent in the male characters of the sample. Highlighting the emotional aspect of female characters in contrast with the restrained male attitude reproduces gender biases. Stereotypical gender representation in children’s literature cultivates further discrimination among men and women.

Keywords: children's literature, female representation, gender socialization, gender studies

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9841 Trainability of Executive Functions during Preschool Age Analysis of Inhibition of 5-Year-Old Children

Authors: Christian Andrä, Pauline Hähner, Sebastian Ludyga

Abstract:

Introduction: In the recent past, discussions on the importance of physical activity for child development have contributed to a growing interest in executive functions, which refer to cognitive processes. By controlling, modulating and coordinating sub-processes, they make it possible to achieve superior goals. Major components include working memory, inhibition and cognitive flexibility. While executive functions can be trained easily in school children, there are still research deficits regarding the trainability during preschool age. Methodology: This quasi-experimental study with pre- and post-design analyzes 23 children [age: 5.0 (mean value) ± 0.7 (standard deviation)] from four different sports groups. The intervention group was made up of 13 children (IG: 4.9 ± 0.6), while the control group consisted of ten children (CG: 5.1 ± 0.9). Between pre-test and post-test, children from the intervention group participated special games that train executive functions (i.e., changing rules of the game, introduction of new stimuli in familiar games) for ten units of their weekly sports program. The sports program of the control group was not modified. A computer-based version of the Eriksen Flanker Task was employed in order to analyze the participants’ inhibition ability. In two rounds, the participants had to respond 50 times and as fast as possible to a certain target (direction of sight of a fish; the target was always placed in a central position between five fish). Congruent (all fish have the same direction of sight) and incongruent (central fish faces opposite direction) stimuli were used. Relevant parameters were response time and accuracy. The main objective was to investigate whether children from the intervention group show more improvement in the two parameters than the children from the control group. Major findings: The intervention group revealed significant improvements in congruent response time (pre: 1.34 s, post: 1.12 s, p<.01), while the control group did not show any statistically relevant difference (pre: 1.31 s, post: 1.24 s). Likewise, the comparison of incongruent response times indicates a comparable result (IG: pre: 1.44 s, post: 1.25 s, p<.05 vs. CG: pre: 1.38 s, post: 1.38 s). In terms of accuracy for congruent stimuli, the intervention group showed significant improvements (pre: 90.1 %, post: 95.9 %, p<.01). In contrast, no significant improvement was found for the control group (pre: 88.8 %, post: 92.9 %). Vice versa, the intervention group did not display any significant results for incongruent stimuli (pre: 74.9 %, post: 83.5 %), while the control group revealed a significant difference (pre: 68.9 %, post: 80.3 %, p<.01). The analysis of three out of four criteria demonstrates that children who took part in a special sports program improved more than children who did not. The contrary results for the last criterion could be caused by the control group’s low results from the pre-test. Conclusion: The findings illustrate that inhibition can be trained as early as in preschool age. The combination of familiar games with increased requirements for attention and control processes appears to be particularly suitable.

Keywords: executive functions, flanker task, inhibition, preschool children

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9840 Off-Topic Text Detection System Using a Hybrid Model

Authors: Usama Shahid

Abstract:

Be it written documents, news columns, or students' essays, verifying the content can be a time-consuming task. Apart from the spelling and grammar mistakes, the proofreader is also supposed to verify whether the content included in the essay or document is relevant or not. The irrelevant content in any document or essay is referred to as off-topic text and in this paper, we will address the problem of off-topic text detection from a document using machine learning techniques. Our study aims to identify the off-topic content from a document using Echo state network model and we will also compare data with other models. The previous study uses Convolutional Neural Networks and TFIDF to detect off-topic text. We will rearrange the existing datasets and take new classifiers along with new word embeddings and implement them on existing and new datasets in order to compare the results with the previously existing CNN model.

Keywords: off topic, text detection, eco state network, machine learning

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9839 Geopolymer Stabilization of Earth Building Material for Construction 3D Printing

Authors: Timur Mukhametkaliyev

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The earthen material possesses low compression strength, and it is highly sensitive to the water content. Different binders can be added (Portland cement or lime) to improve the durability and the mechanical characteristics of earthen material, but the production of these binders has high embodied energy and results in an increase in world CO₂ emission. Geopolymers are binders which can be synthesized at low temperature in alkaline solutions from raw materials consisting of amorphous aluminosilicates. Geopolymers are an attractive substitution of Portland cement and can be used as an excellent stabilization for earthen material. In this study, earthen material stabilized with geopolymer binder for use in construction 3D printing was developed. Construction 3D printing offers freedom of design, waste minimisation, customisation, reduced labour, and automation. For successful 3D printing, the properties of used material are the most important aspects because they require adaptability for extrusion and controlled time of hardening for the binder.

Keywords: 3D printing, building construction, geopolymer, architecture

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9838 Preventing Discharge to No Fixed Address-Youth (NFA-Y)

Authors: Cheryl Forchuk, Sandra Fisman, Steve Cordes, Dan Catunto, Katherine Krakowski, Melissa Jeffrey, John D’Oria

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The discharge of youth aged 16-25 from hospital into homelessness is a prevalent issue despite research indicating social, safety, health and economic detriments on both the individual and community. Lack of stable housing for youth discharged into homelessness results in long-term consequences, including exacerbation of health problems and costly health care service use and hospital readmission. People experiencing homelessness are four times more likely to be readmitted within one month of discharge and hospitals must spend $2,559 more per client. Finding safe housing for these individuals is imperative to their recovery and transition back to the community. People discharged from hospital to homelessness experience challenges, including poor health outcomes and increased hospital readmissions. Youth are the fastest-growing subgroup of people experiencing homelessness in Canada. The needs of youth are unique and include supports related to education, employment opportunities, and age-related service barriers. This study aims to identify the needs of youth at risk of homelessness by evaluating the efficacy of the “Preventing Discharge to No Fixed Address – Youth” (NFA-Y) program, which aims to prevent youth from being discharged from hospital into homelessness. The program connects youth aged 16-25 who are inpatients at London Health Sciences Centre and St. Joseph’s Health Care London to housing and financial support. Supports are offered through collaboration with community partners: Youth Opportunities Unlimited, Canadian Mental Health Association Elgin Middlesex, City of London Coordinated Access, Ontario Works, and Salvation Army’s Housing Stability Bank. This study was reviewed and approved by Western University’s Research Ethics Board. A series of interviews are being conducted with approximately ninety-three youth participants at three time points: baseline (pre-discharge), six, and twelve months post-discharge. Focus groups with participants, health care providers, and community partners are being conducted at three-time points. In addition, administrative data from service providers will be collected and analyzed. Since homelessness has a detrimental effect on recovery, client and community safety, and healthcare expenditure, locating safe housing for psychiatric patients has had a positive impact on treatment, rehabilitation, and the system as a whole. If successful, the findings of this project will offer safe policy alternatives for the prevention of homelessness for at-risk youth, help set them up for success in their future years, and mitigate the rise of the homeless youth population in Canada.

Keywords: youth homelessness, no-fixed address, mental health, homelessness prevention, hospital discharge

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