scholarly journals Strategies to Minimise Numerical Ventilation in CFD Simulations of High-Speed Planing Hulls

2019 ◽  
Author(s):  
Angus Gray-Stephens ◽  
Tahsin Tezdogan ◽  
Sandy Day
Keyword(s):  
Free Surface ◽  
High Speed ◽  
Positive Impact ◽  
Entrance Angle ◽  
The Public ◽  
Depth Analysis ◽  
Niche Area ◽  
Prism Layer ◽  
The Impact ◽  
Mesh Refinements

Abstract Numerical Ventilation (NV) is a well-known problem that occurs when the Volume of Fluid method is used to model vessels with a bow that creates a small, acute entrance angle with the free surface. These are typical of both planing hulls and yachts. There is a general lack of discussion focusing upon Numerical Ventilation available within the public domain, which is attributable to the fact that it only affects such a niche area of naval architecture. The information available is difficult to find, often fleetingly mentioned in papers with a different focus. Numerical Ventilation may be considered one of the main sources of error in numerical simulations of planing hulls and as such warrants an in-depth analysis. This paper sets out to bring together the available work, as well as performing its own investigation into the problem to develop a better understanding of Numerical Ventilation and present alternate solutions. Additionally, the success and impact of different approaches is presented in an attempt to help other researchers avoid and correct for Numerical Ventilation. Interface smearing caused by the simulations inability to track the free surface is identified as the main source of Numerical Ventilation. This originates from the interface between the volume mesh and the prism layer mesh. This study looks into the interface to identify strategies that minimise Numerical Ventilation, presenting a novel solution to prism layer meshing that was found to have a positive impact. Through the implementation of a modified High Resolution Interface Capture (HRIC) scheme and the correct mesh refinements, it is possible to minimise the impact of Numerical Ventilation to a level that will not affect the results of a simulation and is acceptable for engineering applications.

scholarly journals Minimising Numerical Ventilation in CFD Simulations of High-speed Planing Hulls

2021 ◽  
pp. 1-33
Author(s):  
Angus Gray-Stephens ◽  
Tahsin Tezdogan ◽  
Sandy Day
Keyword(s):  
Free Surface ◽  
High Speed ◽  
Volume Of Fluid Method ◽  
Cfd Simulations ◽  
Entrance Angle ◽  
Depth Analysis ◽  
Prism Layer ◽  
The Impact ◽  
Mesh Refinements ◽  
Volume Mesh

Abstract Numerical Ventilation (NV) is a well-known problem that occurs when the Volume of Fluid method is used to model vessels with a bow that creates an acute entrance angle with the free surface, as is typical for both planing hulls and yachts. Numerical Ventilation may be considered one of the main sources of error in numerical simulations of planing hulls and as such warrants an in-depth analysis. This paper sets out to bring together the available work, as well as performing its own investigation into the problem to develop a better understanding of Numerical Ventilation and present alternate solutions. Additionally, the success and impact of different approaches is presented in an attempt to help other researchers avoid and correct for Numerical Ventilation. Interface smearing caused by the simulation being unable to track the free surface is identified as the main source of Numerical Ventilation. This originates from the interface between the volume mesh and the prism layer mesh. This study investigates this interface, presenting a novel solution to prism layer meshing that was found to minimize Numerical Ventilation. Through the implementation of a modified High Resolution Interface Capture (HRIC) scheme and the correct mesh refinements, it is possible to minimize the impact of Numerical Ventilation to a level that will not affect the results of a simulation and is acceptable for engineering applications.

Evaluation of the impact of public investment programs on social and economic performance of territories

2019 ◽  
pp. 109-123
Author(s):  
I. E. Limonov ◽  
M. V. Nesena
Keyword(s):  
Bayesian Modeling ◽  
Positive Impact ◽  
Public Investment ◽  
Difference In Differences ◽  
The Public ◽  
Export Activity ◽  
Regional Investment ◽  
The Difference ◽  
The Impact ◽  
Development Institution

The purpose of this study is to evaluate the impact of public investment programs on the socio-economic development of territories. As a case, the federal target programs for the development of regions and investment programs of the financial development institution — Vnesheconombank, designed to solve the problems of regional development are considered. The impact of the public interventions were evaluated by the “difference in differences” method using Bayesian modeling. The results of the evaluation suggest the positive impact of federal target programs on the total factor productivity of regions and on innovation; and that regional investment programs of Vnesheconombank are improving the export activity. All of the investments considered are likely to have contributed to the reduction of unemployment, but their implementation has been accompanied by an increase in social inequality.

IMPACT OF GOVERNMENT DEBT ON FINANCIAL SECURITY OF UKRAINE

2017 ◽  
Author(s):  
Olena Pikaliuk ◽  
◽  
Dmitry Kovalenko ◽  
Keyword(s):  
Economic Development ◽  
Public Debt ◽  
Positive Impact ◽  
The State ◽  
Financial Security ◽  
State Budget ◽  
The Public ◽  
Debt Security ◽  
The Stability ◽  
The Impact

One of the main criteria for economic development is the size of the public debt and its dynamics. The article considers the impact of public debt on the financial security of Ukraine. The views of scientists on the essence of public debt and financial security of the state are substantiated. An analysis of the dynamics and structure of public debt of Ukraine for 2014-2019. It is proved that one of the main criteria for economic development is the size of public debt and its dynamics. State budget deficit, attracting and using loans to cover it have led to the formation and significant growth of public debt in Ukraine. The volume of public debt indicates an increase in the debt security of the state, which is a component of financial security. Therefore, the issue of the impact of public debt on the financial security of Ukraine is becoming increasingly relevant. The constant growth and large amounts of debt make it necessary to study it, which will have a positive impact on economic processes that will ensure the stability of the financial system and enhance its security.

Does motivation play moderating role on organizational citizenship behavior? Evidence from Indonesian telecommunication firms

2021 ◽  
pp. 1667-1676
Author(s):  
Maria Grace Herlina ◽  
Nopriadi Saputra
Keyword(s):  
Transformational Leadership ◽  
Organizational Citizenship ◽  
Organizational Citizenship Behavior ◽  
Structural Equation ◽  
High Speed ◽  
Extrinsic Motivation ◽  
Work Motivation ◽  
Positive Impact ◽  
Citizenship Behavior ◽  
The Impact

Highly competitive and continuous business changes in telecommunication industry make organizational citizenship behavior (OCB) strategically important. This research aims to test the impact of transformational leadership of the direct supervisor on working motivation of the employees. Does supervisor's leadership capability impact on employees' work motivation more intrinsically or extrinsically? The study was conducted in an Indonesian telecommunication company which provides television cable and high-speed internet services for the high-rise building in Java and Sumatra. It involved 199 employees as the respondents. The collected data was analyzed with structural equation modelling approach. The statistical test has proved that transformational leadership has a positive impact on work motivation and organizational citizenship behavior. The motivation – both extrinsic motivation and intrinsic motivation, impacts on organizational citizenship behavior significantly. Although transformational does impact on organizational citizenship behavior both directly and indirectly, but the working motivation does not play a mediating role in the relationship between transformation leadership and organizational citizenship behavior.

scholarly journals FORMAÇÃO DO ENFERMEIRO: POLÍTICAS PÚBLICAS NA ATENÇÃO ONCOLÓGICA

2018 ◽  
Vol 9 (3) ◽  
Author(s):  
Andresa Mendonça Oliveira ◽  
Katia Stancato ◽  
Eliete Maria Silva
Keyword(s):  
Public Policy ◽  
Nursing Education ◽  
Professional Practice ◽  
Policy Development ◽  
Positive Impact ◽  
National Policy ◽  
Cancer Control ◽  
Nurse Training ◽  
The Public ◽  
The Impact

Objetivo: Refletir teoricamente sobre a Política Nacional (brasileira) para Prevenção e Controle do Câncer na Rede de Atenção à Saúde das Pessoas com Doenças Crônicas e articulações na formação do enfermeiro e na prática profissional. Metodologia: Reflexão teórica, por meio de questionamentos das pesquisadoras, discussões em grupo e busca na literatura. Resultados: Os trabalhadores que atuam no cuidado ao paciente oncológico possuem papel essencial na efetivação dessa política. Porém, para que sejam implementadas, é necessário que seus princípios estabelecidos façam sentido na formação e nas práticas profissionais. Conclusão: O ensino reflexivo sobre essa política na formação do enfermeiro contribui para melhorias em sua prática, assim como, práticas reflexivas e melhor qualificadas certamente impactam positivamente na formação profissional. O desenvolvimento de políticas públicas com ênfase nas demandas da população pressupõe articulação teórica e prática e transformações sociais.Descritores: Educação Superior; Educação em enfermagem; Políticas públicas de saúde; Prática profissional; Enfermagem Oncológica.NURSING EDUCATION : PUBLIC POLICY AT ONCOLOGI C ATTENTIONObjective: Reflect theoretically about the Public Policies on the Oncological Care, especially the National Policy(Brazilian) for Prevention and Cancer Control in Health Care Network of People with Chronic Diseases and the impact on nurse training and professional practice. Methodology: Theoretical speculation by means of interviews with researchers, group discussions and literature research. Results: Caregivers of oncological patients have an essential role on the effecting this Policy. However, in order to implement this policy, it is necessary that its established principles make sense for nursing education and professional practices. Conclusion: The reflective teaching about this policy in the formation of nurses contributes to improve its practice, as reflective and better qualified practices certainly have a positive impact on vocational education. The public policy development with emphasis on population demands assumes theoretical and practical articulation and social transformations.Descriptors: Education Higher; Education; Nursing; Public Health Policy; Professional Practice; Oncology Nursing.EDUCACIÓN EN ENFERMERÍA: POLÍTICA PÚBLICA EN ATEN CIÓN ONCOLÓGICAObjetivo: reflexionar teóricamente sobre las políticas públicas para atención oncológica, especialmente para la Política Nacional (brasileña) para Prevención y Control del Cáncer en la Red de Salud de Personas con Enfermedades Crónicas e articulaciones en la formación de enfermeras y en la práctica profesional. Metodología: Reflexión teórica por medio de cuestionamientos de los pesquisidores, discusiones en grupo y pesquisa en la literatura. Resultados: Los cuidadores de enfermos oncológicos tienen un papel esencial en la implementación de políticas. Sin embargo, para funcionar, es necesario que sus principios hagan sentido en la formación y en las prácticas profesionales. Conclusión: La enseñanza reflexiva sobre la política en la formación de enfermeros contribuye para mejoras en su práctica, como tal, prácticas reflexivas y más calificadas, sin duda, causan impacto positivo en las prácticas de formación profesional. El desarrollo de las políticas públicas con énfasis en las demandas de la población presupone la articulación teórica y práctica y la transformación social.Descriptores: Educación Superior; Educación en Enfermería; Políticas Públicas de Salud; Práctica Profesional; Enfermería Oncológica.

scholarly journals Accessibility in the regional CGE framework: the effects of major transport infrastructure investments in Poland

2020 ◽  
Author(s):  
Bartlomiej Rokicki ◽  
Eduardo A. Haddad ◽  
Jonathan M. Horridge ◽  
Marcin Stępniak
Keyword(s):  
High Speed ◽  
Positive Impact ◽  
Public Funding ◽  
Transport Infrastructure ◽  
Infrastructure Investment ◽  
Major Road ◽  
Road Infrastructure ◽  
Infrastructure Investments ◽  
Investment Spending ◽  
The Impact

AbstractSince its EU accession, Poland has invested strongly in the development of fast road transport network. As a result, the total length of modern, high-speed roads has increased from around 500 km in 2005 to over 3000 km in 2015. Yet, while the positive impact of transport infrastructure investment on overall accessibility is unquestionable there are no studies that assess its influence on economic development of particular regions. This paper applies a regional dynamic CGE model to measure the effects of big transport infrastructure investments in Polish NUTS2 regions. We use data on both investment spending and accessibility improvement (expressed as a reduction in transport margins) in order to distinguish between possible short and long term impacts. We find that there exist significant disparities in the impact between regions with high share of major road infrastructure investment undertaken by private investors and the ones that relied fully on public funding. In the case of the former, the lack of analyzed investment would lead to relatively significant decrease in real GDP or average employment. In the case of the latter, the impact of major road infrastructure investment is almost negligible.

Design of Microplastics Citizen Science Kit

2020 ◽  
Author(s):  
Rachael Hughson-Gill
Keyword(s):  
Data Collection ◽  
Citizen Science ◽  
Large Scale ◽  
Positive Impact ◽  
Research Process ◽  
Freshwater Ecosystems ◽  
Freshwater Systems ◽  
The Public ◽  
Plastic Bags ◽  
The Impact

<p>Microplastics are an ever-increasing problem. Every river that was tested in a recent study found the presence of microplastics, with 80% of all plastic in the ocean coming from upstream. Despite this, there is little understanding into the abundance of plastic, its characteristics and the full impact that is it having on marine, freshwater ecosystems and wider ecological systems.</p><p> </p><p>Current fresh water monitoring does not consider the fluid dynamics of rivers, is difficult to use and is inaccessible to the wider public. My project will focus on creating a product that allows for the large-scale data collection of microplastic through citizen science. Allowing groups of people to analyse their local natural environment for the presence and abundance of microplastics within the water. This method of data collection could provide information on a scale that is not possible with traditional methods and would allow for the comparison between freshwater systems. This comparison is fundamental to begin to fill the knowledge gaps around the understanding of microplastics.</p><p> </p><p>Inaccessibility of monitoring to the public is not just through tools but also through the current communication of data with research rarely breaking into the public domain. Citizen science offers not just an improvement in understanding but also offers an opportunity for engagement with the public body. Increasing awareness of the impact of habits round plastic through the sharing of monitoring data can generate the much-needed change on both an individual and policy level to address the problem from the source. This method of change through public opinion can be seen to have an effect on freshwater systems through microbeads ban, plastic bags, plastic straws and industrial pollution regulation.</p><p> </p><p>Through the creation of this product a multidisciplinary approach that blends engineering and design practices is implemented. The wholistic approach to creation is something that is fundamental in the success of tools and therefore the success of the research that is implemented through them. A tool such as this whose function is within the public engagement of its use - increased awareness, as well as the outcome of its use - microplastics data, is required to have an engaging user experience as well as data integrity implemented through engineering design.</p><p> </p><p>This project offers an opportunity to show the importance of the design process within research tools to aid the research process and the positive impact that can come from it.</p>

scholarly journals Does Farmland Size Affect the Collective Action in Rural Areas? An Empirical Study on the Public Irrigation System in China

2021 ◽  
Vol 292 ◽  
pp. 01028
Author(s):  
Liangzhen Zang ◽  
Yiqing Su
Keyword(s):  
Public Sector ◽  
Collective Action ◽  
Rural Areas ◽  
Positive Impact ◽  
Irrigation System ◽  
The Public ◽  
Land Circulation ◽  
Per Capita ◽  
Agricultural Business ◽  
The Impact

Since smallholders accounted for a high proportion of 98.1% among the 207 million agricultural business households across China, it is particularly important to study the impact of farmland size on the provision of public goods attached to the public sector industries from the perspective of the irrigation collective action in rural areas. Based on the survey data of 283 villages in China, this paper finds that the farmland size has a positive impact on irrigation collective action, although the average of per capita farmland area is only 0.214 hectares in each household of China. Therefore, it is necessary to promote the farmland scale operation by land circulation, so as to improve the ability of collective action and the development of public sector industries in rural areas of China.

scholarly journals 5G Radiation and Potential Risks to the Environment and Human Health

2021 ◽  
Vol 12 (6) ◽  
pp. 1689-1693
Author(s):  
Hasan J. Hasan, Ali J. Yosef, Haider Abed Hachem
Keyword(s):  
Human Health ◽  
High Speed ◽  
Rapid Development ◽  
Health And Safety ◽  
Radio Spectrum ◽  
The Public ◽  
Potential Risks ◽  
Public Exposure ◽  
New Generation ◽  
The Impact

      The rapid development in wireless communication technology and the urgent need to develop it has led to an increase in the public exposure to more radio spectrum frequencies. The mountain increases in terms of the damage caused by these wireless technologies for the 2G, 3G and 4G generations ending with the new technique, which is 5G. As a result of the urgent need for fast communications and wide packages of data, only a new generation of communications has emerged, which is 5G, which enjoys high speed and broadcasts in short waves and high frequency. There is great concern about the impact of these technologies on human health and safety. This technique works at relatively higher frequencies than the previously used technologies. This research sheds light on some of the expected harms of these technologies and the result of using these techniques, where the damages on the human body in general, the skin and the human eye in particular, are addressed, as well as their impact on the environment and plants in general.

scholarly journals Mathematical Modeling of Intellectual Capital and Business Efficiency of Small and Medium Enterprises

Mathematics ◽  
2021 ◽  
Vol 9 (18) ◽  
pp. 2305
Author(s):  
Wadim Strielkowski ◽  
Aida Guliyeva ◽  
Ulviyya Rzayeva ◽  
Elena Korneeva ◽  
Anna Sherstobitova
Keyword(s):  
Mathematical Modeling ◽  
Intellectual Capital ◽  
Positive Impact ◽  
Small And Medium Enterprises ◽  
Economies In Transition ◽  
Depth Analysis ◽  
Customer Capital ◽  
Cis Countries ◽  
Medium Enterprises ◽  
The Impact

Our paper aims at testing the impact of separate elements of the intellectual capital (IC) represented for instance by the human, structural, and customer capital, on the functioning and performance of the small and medium-sized enterprises (SMEs) using mathematical modeling. We assess the intellectual capital with respect to the resource-based view theory. Our study is based on the data obtained from the 206 surveys with the representatives of small and medium-sized enterprises from Commonwealth of Independent States (CIS) countries. We employed a mathematical modeling approach as well as the SPSS application package in order to test our hypotheses about the influence of intellectual capital on the enterprise’s efficiency. Our results helped us to determine that the concept of intellectual capital is practically not used in the management of small and medium-sized enterprises in CIS countries. It becomes apparent that individual techniques for managing intellectual resources can only be identified intuitively, based on an in-depth analysis of the current tasks facing managers. These findings confirmed the positive impact of intellectual capital on the performance of small and medium-sized enterprises in the conditions of the economies in transition represented hereinafter in our paper by CIS countries, but only with the availability of financial resources and with some important reservations.

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