Impacts of ambient pressure on the stability of smoke layers and maximum smoke temperature under ceiling in ventilated tunnels

2021 ◽  
pp. 1420326X2110130
Author(s):  
Tong Xu ◽  
Fei Tang ◽  
Xuhao Xu ◽  
Qing He
Keyword(s):  
Ambient Pressure ◽  
Longitudinal Velocity ◽  
Shear Velocity ◽  
Tunnel Fire ◽  
Study Results ◽  
Smoke Layer ◽  
The Stability ◽  
Fire Accidents ◽  
In Fire ◽  
The Impact

In tunnel fire, smoke is a great threat to successful emergency escapes, and its spreading patterns at high altitude tunnel may differ. Therefore, the impact of ambient pressure on the stability of smoke layers and maximum smoke temperature under ceiling in ventilated tunnels were investigated in this study. Results show that the temperature of smoke layer is negatively correlated with the longitudinal velocity and ambient pressure. Besides, the influence of longitudinal velocity at different ambient pressures on the shear velocity between the smoke and air layers was further studied. Using Richardson number ( Ri) and Froude number ( Fr), smoke flow can be classified into three patterns, namely stable and obvious smoke stratification ( Ri>3.2 or Fr < 0.38), a stable smoke layer but with blurred interface (2.3 <  Ri < 3.2 or 0.38 <  Fr < 0.53) and a completely unstable smoke stratification ( Ri < 2.3 or Fr > 0.53). Furthermore, a model has been developed to predict maximum smoke temperature under the tunnel ceiling, which agrees well with previous studies at standard atmospheric pressure. The results of the present work provide information for tunnel structure protection and safe evacuation in fire accidents at different ambient pressures.

scholarly journals Формирование среды реализации цифровых инициатив сотрудников банка

2019 ◽  
pp. 48-54
Author(s):  
Тарас Гриценко ◽  
Жанна Передера ◽  
Анна Теряева
Keyword(s):  
Banking Sector ◽  
Economic Security ◽  
New Professionals ◽  
Advantages And Disadvantages ◽  
Study Results ◽  
The Matrix ◽  
Banking Business ◽  
The Stability ◽  
Definition Of ◽  
The Impact

В работе рассматривается возможность формирования в банковском секторе среды, в которой сотрудники смогут самостоятельно реализовывать цифровые инициативы для развития компании и самообучения. Обоснована необходимость её наличия. Проведен анализ соответствия поставленной проблемы российским и мировым трендам на основе изучения федеральных программ и оценок рейтинговых агентств. В результате исследования разработан бизнес-процесс реализации цифровых инициатив, про-веден конкурентный анализ его преимуществ и недостатков перед традиционным подходом к обучению. The article discusses the possibility of forming in the banking business an environment in which employees will be able to in-dependently implement digital initiatives for the development of the company and self-learning. The necessity of its presence is grounded. The analysis of compliance of the problem with the trends in Russia and the world based on the study of Federal programs and ratings agencies. To attract new staff with the necessary knowledge, banks have a number of tools - business classes, sponsorship programs, mentoring, hackathons, man-agement fights, case-championships, etc. It has been revealed that new professionals with technical skills can solve complex problems and generate products. But it’s difficult for them to dive into the banking sector, study its features and offer their own solutions to problems. It was also revealed that the company is interested in product results that are practice oriented. Com-bining product results and training is only possible by creating an environment in which they can discuss their ideas, find sup-port and implement them. As a result, a business process for the implementation of digital initiatives has been formed, a competi-tive analysis of its advantages and disadvantages over the tradi-tional approach to training has been conducted. strategies. The leading method of research is the definitions according grouping to the principles of the matrix method. It was revealed that the economic security concept is disclosed using factors freely com-bined into three groups (includes: sustainability, protection of interests, ensuring sovereignty), and the most common definitions are built using words-markers: state, security, advantage, process. One of the main study results is an algorithm for constructing the definition of the economic security concept, which allows to model and refine the definition of the concept based on the initial categories, consider-ing the economic context. The author's definition is also formulated, which reflects the interrelation of such components as the protection of interests, the impact of threats, the stability preservation, inde-pendence, ensuring development, self-adaptation and self-reproduction.

Small-bioreactor platform technology as a municipal wastewater additive treatment

2013 ◽  
Vol 69 (3) ◽  
pp. 504-510 ◽  
Author(s):  
Ofir Menashe ◽  
Eyal Kurzbaum
Keyword(s):  
Biological Treatment ◽  
Municipal Wastewater ◽  
Selection Process ◽  
Study Results ◽  
Different Types ◽  
Selective Forces ◽  
The Stability ◽  
Physical And Chemical ◽  
The Impact ◽  
The Relationship

The bioaugmentation treatment approach presents both an economical and environmentally friendly solution for wastewater treatment. However, the use of exogenous bacterial cultures presents several limitations: negative interaction between microorganisms and adaptation to new physical and chemical composite environment. These selective forces create a significant challenge for the introduced culture to achieving the required biomass in order to conduct the target biological treatment. Small-bioreactor platform (SBP) technology is aimed at introducing exogenous bacterial culture with some protection to reduce some of the natural selection process. The current study was aimed at validating the use of SBP technology to improve biological treatment, especially during a stress period, by using macro-encapsulated bioaugmentation treatment. The study results indicate that the use of SBP technology elevates the stability of biological treatment, improving operational factors such as the reduction of foaming phenomena and sludge accumulation. Still, a significant study needs to be conducted to understand the potential of this technology; especially the impact on biological treatment by using different types of microorganisms for different types of wastewaters and the relationship between the biomass within the SBP capsules and the natural microorganisms.

scholarly journals Сущность и классификация категории «экономическая безопасность» в современной экономике

2019 ◽  
pp. 12-24
Author(s):  
Илья Рябков ◽  
Наталья Яшалова
Keyword(s):  
Economic Security ◽  
Economic Research ◽  
Modern Concept ◽  
Clear Understanding ◽  
Study Results ◽  
The Matrix ◽  
Self Adaptation ◽  
The Stability ◽  
Definition Of ◽  
The Impact

Целью настоящего исследования является изучение исторической динамики понятия «экономическая безопасность», его текущих трактовок, систематизация определений че-рез выделение ключевых подходов и терминов, а также выделение унифицированного метода «генерации» понятия «экономическая безопасность» и его подвидовых понятий. В статье через призму подходов различных (по времени и географии) экономических школ проведен анализ формулировок определения, произведена их сравнительная характеристика в ведущих концепциях экономической безопасности (Российская Федерация и Соединенные Штаты Америки). Вы-двинуто предложение о соблюдении непротиворечивой иерархии построения определения «экономическая безопасность» с выявлением отношений со смежными категория-ми и понятиями, представлена авторская формулировка данной категории. One of the fundamental concepts in economic theory is the con-cept of "economic security". In the practice of Russian economic research, since the 1990s there have been numerous and often heterogeneous definitions of this concept. The main purpose of the study was to consider the development of economic security concepts on the historical horizon and the modern concept defi-nitions classification, given by Russian and foreign researchers. The article puts forward the thesis that the maintaining economic process of efficiency and development, both of individual eco-nomic entities and the state, depends on a clear understanding of the economic security concept, the search for approaches to the economic security preservation. Interest is the systematization of the economic security concepts presented in the leading powers strategies. The leading method of research is the definitions according grouping to the principles of the matrix method. It was revealed that the economic security concept is disclosed using factors freely com-bined into three groups (includes: sustainability, protection of interests, ensuring sovereignty), and the most common definitions are built using words-markers: state, security, advantage, process. One of the main study results is an algorithm for constructing the definition of the economic security concept, which allows to model and refine the definition of the concept based on the initial categories, consider-ing the economic context. The author's definition is also formulated, which reflects the interrelation of such components as the protection of interests, the impact of threats, the stability preservation, inde-pendence, ensuring development, self-adaptation and self-reproduction.

On the Smoke Propagation of a Fire in a Tunnel With Concentrated Exhaust Ventilation

2011 ◽  
Author(s):  
Futoshi Tanaka ◽  
Masahiro Kato ◽  
Shouhei Majima ◽  
Nobuyoshi Kawabata ◽  
Tomoki Kikumoto ◽  
...  
Keyword(s):  
Layer Thickness ◽  
Scaling Law ◽  
Experimental Results ◽  
Exhaust Ventilation ◽  
Tunnel Fire ◽  
The People ◽  
Fire Smoke ◽  
Smoke Layer ◽  
Fire Accidents ◽  
Real Scale

In recent years, tunnel fire accidents of about 20 occur every year in Japan. The Nihonzaka and the Sakai tunnel fire accidents are as famous typical examples. When concentrated exhaust ventilation device is activated in such a tunnel fire, it is of concern that the people who take shelter receive damage from the fire smoke. When a tunnel fire occurs, the concentrated exhaust ventilation device is stopped in Japan. Therefore, the research on the use of concentrated exhaust ventilation device at a tunnel fire has not advanced in Japan. The purpose of this study is to clarify the smoke propagation when concentrated exhaust ventilation device is activated. The model tunnel in the scale of 1/5 was used in this study. Froude scaling law was used to make the experimental results of the model tunnel correspond to the real scale tunnel. The concentrated exhaust ventilation device installed on the model tunnel extracts the fire smoke from a chimney. The smoke distribution in the model tunnel was measured with smoke concentration meters. In the case that the exhaust ventilation device was activated, the smoke layer thickness of the downstream of the chimney thinned. However, in the upstream of the chimney, the smoke layer thickness did not change though the exhaust ventilation device was activated.

Dietary Vitamin and Stability of Oral Anticoagulation: Proposal of a Diet with Constant Vitamin K1 Content

1997 ◽  
Vol 77 (03) ◽  
pp. 504-509 ◽  
Author(s):  
Sarah L Booth ◽  
Jacqueline M Charnley ◽  
James A Sadowski ◽  
Edward Saltzman ◽  
Edwin G Bovill ◽  
...  
Keyword(s):  
Dietary Intake ◽  
Vitamin K ◽  
High Performance ◽  
Case Reports ◽  
Food Composition ◽  
Dietary Guidelines ◽  
Dietary Vitamin ◽  
Vitamin K1 ◽  
The Stability ◽  
The Impact

SummaryCase reports cited in Medline or Biological Abstracts (1966-1996) were reviewed to evaluate the impact of vitamin K1 dietary intake on the stability of anticoagulant control in patients using coumarin derivatives. Reported nutrient-drug interactions cannot always be explained by the vitamin K1 content of the food items. However, metabolic data indicate that a consistent dietary intake of vitamin K is important to attain a daily equilibrium in vitamin K status. We report a diet that provides a stable intake of vitamin K1, equivalent to the current U.S. Recommended Dietary Allowance, using food composition data derived from high-performance liquid chromatography. Inconsistencies in the published literature indicate that prospective clinical studies should be undertaken to clarify the putative dietary vitamin K1-coumarin interaction. The dietary guidelines reported here may be used in such studies.

Income Diversification and Bank Efficiency in Vietnam

2017 ◽  
pp. 52-67
Author(s):  
Sang Nguyen Minh
Keyword(s):  
Regression Model ◽  
Commercial Banks ◽  
Banking System ◽  
Operational Efficiency ◽  
Commercial Banking ◽  
Tobit Regression ◽  
Income Diversification ◽  
Positive Effects ◽  
Study Results ◽  
The Impact

This study uses the DEA (Data Envelopment Analysis) method to estimate the technical efficiency index of 34 Vietnamese commercial banks in the period 2007-2015, and then it analyzes the impact of income diversification on the operational efficiency of Vietnamese commercial banks through a censored regression model - the Tobit regression model. Research results indicate that income diversification has positive effects on the operational efficiency of Vietnamese commercial banks in the research period. Based on study results, in this research some recommendations forpolicy are given to enhance the operational efficiency of Vietnam’s commercial banking system.

Some reflections on social structure: Theoretical and practical aspects

2020 ◽  
Vol 18 (6) ◽  
pp. 1063-1078
Author(s):  
T.N. Skorobogatova ◽  
I.Yu. Marakhovskaya
Keyword(s):  
Service Industry ◽  
External Factors ◽  
Infrastructure Development ◽  
Social Infrastructure ◽  
Social Sphere ◽  
The Social ◽  
Study Results ◽  
The Republic ◽  
Internal And External Factors ◽  
The Impact

Subject. This article discusses the role of social infrastructure in the national economy and analyzes the relationship between the notions of Infrastructure, Service Industry and Non-Productive Sphere. Objectives. The article aims to outline a methodology for development of the social infrastructure of Russia's regions. Methods. For the study, we used the methods of statistical and comparative analyses. The Republic of Crimea and Rostov Oblast's social infrastructure development was considered as a case study. Results. The article finds that the level of social infrastructure is determined by a number of internal and external factors. By analyzing and assessing such factors, it is possible to develop promising areas for the social sphere advancement. Conclusions. Assessment and analysis of internal factors largely determined by the region's characteristics, as well as a comprehensive consideration of the impact of external factors will help ensure the competitiveness of the region's economy.

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.

Influence of internal and external risks on sustainability of financial system of Аltai krai

2018 ◽  
Vol 35 (4) ◽  
pp. 133-136
Author(s):  
R. N. Ibragimov
Keyword(s):  
Sustainable Development ◽  
Financial Stability ◽  
Management Strategy ◽  
Financial System ◽  
Risk Management Strategy ◽  
The Sustainable Development ◽  
The Stability ◽  
The Impact

The article examines the impact of internal and external risks on the stability of the financial system of the Altai Territory. Classification of internal and external risks of decline, affecting the sustainable development of the financial system, is presented. A risk management strategy is proposed that will allow monitoring of risks, thereby these measures will help reduce the loss of financial stability and ensure the long-term development of the economy of the region.

The Impact of Bar Service Operation Practices on Organizational Performance in Indian Hotel Industry

2015 ◽  
Vol 8 (1) ◽  
Author(s):  
Mohinder C. Dhiman ◽  
Abhishek Ghai
Keyword(s):  
Organizational Performance ◽  
Hotel Industry ◽  
Demographic Variables ◽  
Study Results ◽  
Service Operation ◽  
Managerial Implications ◽  
Overall Performance ◽  
The Impact ◽  
The Relationship ◽  
Bivariate Test

The paper has a two fold purpose - examine the impact of bar service operation practices (BSOP) on organizational performance (OP) and study the relationship between organizational performance and demographic variables. Based on a survey of 362 bar managers perceptions on the impact of bar service operation practices on organizational performance were assessed by 59 practices and 6 demographic variables. Bivariate test and ANOVA were employed to test the working hypothesis in the study. Results indicated that there is a positive relationship between the bar service operation practices and organizational performance. Further, the results indicate some practical and managerial implications to improve organizational overall performance.

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