Collapse Evolvement Analysis of Upstream Tailings Dam in Flood Situation

2012 ◽  
Vol 212-213 ◽  
pp. 759-764
Author(s):  
Xiao Fei Jing ◽  
Wei Zhong Zhang ◽  
Yu Long Chen ◽  
Zhi Yong Cai
Keyword(s):  
Rural Areas ◽  
Flood Hazard ◽  
Industrial Processes ◽  
Simulation Methods ◽  
Tailings Dam ◽  
Collapse Mode ◽  
Wide Range ◽  
Numerical Simulation Methods ◽  
And Control ◽  
Important Significance

Very large volume of mined ore materials are processed annually to obtain the various types of minerals that are essential to industrial processes, the upstream tailings dam is usually constructed to store these wastes. But with the increasing of dam quantities, the tailings dam collapsing in flood which are among the most dangerous hazards that affect mountainous and rural areas in a wide range of environments become more and more. Therefore it’s necessary to analyze the collapse mode of upstream tailings dam in flood situation. This paper using the physical model experiment and numerical simulation methods to research on the displacement, saturation line, stress and the broken processes, and the collapse mode of upstream tailings dam in flood water encountered in 100 years are explored. The results have very important significance and scientific support to understand the mechanism of collapse and broken mode deeply, and which have any new exploration for the prevention and control in flood hazard.

scholarly journals Mobility, surveillance and control of children and young people in the everyday: perspectives from sub-Saharan Africa

2011 ◽  
Vol 9 (1/2) ◽  
pp. 114-131 ◽  
Author(s):  
Gina Porter ◽  
Kate Hampshire ◽  
Alister Munthali ◽  
Elsbeth Robson
Keyword(s):  
Young People ◽  
Rural Areas ◽  
Life Histories ◽  
Time Of Day ◽  
Sub Saharan Africa ◽  
Children And Young People ◽  
Research With Children ◽  
Wide Range ◽  
Independent Travel ◽  
And Control

Surveillance of children and young people in non-Western contexts has received little attention in the literature.   In this paper we draw principally on our research in one African country, Malawi, to examine the ways in which their independent travel is shaped by  (usually adult-directed) surveillance and control in diverse urban and rural contexts.   Surveillance is interpreted very broadly, because our empirical data indicates a range of practices whereby a close watch is kept over children as they move around their community and travel out to other locations.  In some cases we suggest that surveillance of children and young people becomes internalized self-surveillance, such that no external social control is required to police their movements.Our evidence, from eight research sites, brings together a wide range of source material, including findings from intensive qualitative research with children and adults (in-depth interviews, accompanied walks, focus groups, life histories) and a follow-up questionnaire survey administered to children aged 7 - 18 years [N=1,003].  Although many of the children in our study attend school,  local economic circumstances in both urban and rural areas of  Malawi commonly require children’s participation from an early age in a much broader range of productive and reproductive work activities than is usual in Western contexts, with corresponding impact on daily patterns of movement.  Children may have to travel substantial distances for school, in support of family livelihoods, and for other purposes (including social events): the necessity for independent travel is common, and frequently raises concerns among parents and other adults in their communities such that surveillance is considered essential.  This is achieved principally by encouraging travel in groups of children. We show how young people’s independent travel  is mediated by (urban and rural) locational context, time of day, age and, in particular, by gender, and how adult efforts at surveillance may help shape resistances in the interstitial spaces which mobility itself provides.

scholarly journals Discharge coefficient of small sonic nozzles

2014 ◽  
Vol 18 (5) ◽  
pp. 1505-1510 ◽  
Author(s):  
Zhao-Qin Yin ◽  
Dong-Sheng Li ◽  
Jin-Long Meng ◽  
Ming Lou
Keyword(s):  
Gas Flow ◽  
Discharge Coefficient ◽  
Flow Characteristics ◽  
Simulation Methods ◽  
Nozzle Throat ◽  
Sonic Nozzle ◽  
Numerical Simulation Methods ◽  
Shape Influence ◽  
And Control ◽  
Diffuser Angle

The purpose of this investigation is to understand flow characteristics in mini/micro sonic nozzles, in order to precisely measure and control miniscule flowrates. Experimental and numerical simulation methods have been used to study critical flow Venturi nozzles. The results show that the nozzle?s size and shape influence gas flow characteristics which leading the boundary layer thickness to change, and then impact on the discharge coefficient. With the diameter of sonic nozzle throat decreasing, the discharge coefficient reduces. The maximum discharge coefficient exits in the condition of the inlet surface radius being double the throat diameter. The longer the diffuser section, the smaller the discharge coefficient becomes. Diffuser angle affects the discharge coefficient slightly.

Helicopter icing

2010 ◽  
Vol 114 (1152) ◽  
pp. 83-90 ◽  
Author(s):  
Y. Cao ◽  
K. Chen
Keyword(s):  
Cfd Simulation ◽  
Simulation Methods ◽  
Calculation Methods ◽  
Vehicle Performance ◽  
Wide Range ◽  
Air Vehicle ◽  
Alternative Means ◽  
Numerical Simulation Methods ◽  
Helicopter Aerodynamics ◽  
Computational Fluid Dynamics Cfd

Abstract Due to constraints of natural condition, cost and of available time associated with model fabrication and for extensive wind-tunnel tests or flight tests, Computational Fluid Dynamics (CFD) simulation was considered an alternative means of providing air vehicle icing simulation and aeromechanic performance analysis. Full-scale icing experiments and, therefore, certification and cost can be significantly reduced by developing full-numerical simulation methods to evaluate the air vehicle performance for a wide range of icing conditions. This paper summarises helicopter icing simulation methods that include the development of helicopter aerodynamics, calculation methods of helicopter icing, icing protection system performance, icing effects on the helicopter performance, and some challenges in helicopter icing simulation.

Influencia de las condiciones de secado solar en la coloración de plantas medicinales

2019 ◽  
pp. 28-34
Author(s):  
Margarita Castillo-Téllez ◽  
Beatriz Castillo-Téllez ◽  
Juan Carlos Ovando-Sierra ◽  
Luz María Hernández-Cruz
Keyword(s):  
Medicinal Plants ◽  
Forced Convection ◽  
Rural Areas ◽  
Color Change ◽  
Drying Process ◽  
Scientific Medicine ◽  
Drying Time ◽  
Bacterial Proliferation ◽  
Wide Range ◽  
Very High

For millennia, humans have used hundreds of medicinal plants to treat diseases. Currently, many species with important characteristics are known to alleviate a wide range of health problems, mainly in rural areas, where the use of these resources is very high, even replacing scientific medicine almost completely. This paper presents the dehydration of medicinal plants that are grown in the State of Campeche through direct and indirect solar technologies in order to evaluate the influence of air flow and temperature on the color of the final product through the L* a* scale. b*, analyzing the activity of water and humidity during the drying process. The experimental results showed that the direct solar dryer with forced convection presents a little significant color change in a drying time of 400 min on average, guaranteeing the null bacterial proliferation and reaching a final humidity between 9 % and 11 %.

THE SOME QUESTIONS OF AUTONOMOUS MOTION AND MANAGEMENT OF LAND-MOBILE ROBOTIC COMPLEXES FOR UKRAINIAN GROUND FORCESE

2019 ◽  
pp. 53-58
Author(s):  
О. Кravchuk ◽  
V. Symonenkov ◽  
I. Symonenkova ◽  
O. Hryhorev
Keyword(s):  
Large Scale ◽  
Armed Forces ◽  
Distributed Information ◽  
Wide Range ◽  
Highly Effective ◽  
Information Management Systems ◽  
Robotic Devices ◽  
Principles And Standards ◽  
And Control ◽  
The Eu

Today, more than forty countries of the world are engaged in the development of military-purpose robots. A number of unique mobile robots with a wide range of capabilities are already being used by combat and intelligence units of the Armed forces of the developed world countries to conduct battlefield intelligence and support tactical groups. At present, the issue of using the latest information technology in the field of military robotics is thoroughly investigated, and the creation of highly effective information management systems in the land-mobile robotic complexes has acquired a new phase associated with the use of distributed information and sensory systems and consists in the transition from application of separate sensors and devices to the construction of modular information subsystems, which provide the availability of various data sources and complex methods of information processing. The purpose of the article is to investigate the ways to increase the autonomy of the land-mobile robotic complexes using in a non-deterministic conditions of modern combat. Relevance of researches is connected with the necessity of creation of highly effective information and control systems in the perspective robotic means for the needs of Land Forces of Ukraine. The development of the Armed Forces of Ukraine management system based on the criteria adopted by the EU and NATO member states is one of the main directions of increasing the effectiveness of the use of forces (forces), which involves achieving the principles and standards necessary for Ukraine to become a member of the EU and NATO. The inherent features of achieving these criteria will be the transition to a reduction of tasks of the combined-arms units and the large-scale use of high-precision weapons and land remote-controlled robotic devices. According to the views of the leading specialists in the field of robotics, the automation of information subsystems and components of the land-mobile robotic complexes can increase safety, reliability, error-tolerance and the effectiveness of the use of robotic means by standardizing the necessary actions with minimal human intervention, that is, a significant increase in the autonomy of the land-mobile robotic complexes for the needs of Land Forces of Ukraine.

scholarly journals Information and information resources in COVID-19: Awareness, control, and prevention

2021 ◽  
pp. 096100062110165
Author(s):  
Mohammadhiwa Abdekhoda ◽  
Fatemeh Ranjbaran ◽  
Asghar Sattari
Keyword(s):  
Low Cost ◽  
Information Resources ◽  
Age And Gender ◽  
Use Of Resources ◽  
Strategic Approach ◽  
Wide Range ◽  
Data Collection Instrument ◽  
Control And Prevention ◽  
And Gender ◽  
And Control

This study was conducted with the aim of evaluating the role of information and information resources in the awareness, control, and prevention of COVID-19. This study was a descriptive-analytical survey in which 450 participants were selected for the study. The data collection instrument was a researcher-made questionnaire. Descriptive and inferential statistics were used to analyze the data through SPSS. The findings show that a wide range of mass media has become well known as information resources for COVID-19. Other findings indicate a significant statistical difference in the rate of using information resources during COVID-19 based on age and gender; however, this difference is not significant regarding the reliability of information resources with regard to age and gender. Health information has an undisputable role in the prevention and control of pandemic diseases such as COVID-19. Providing accurate, reliable, and evidence-based information in a timely manner for the use of resources and information channels related to COVID-19 can be a fast and low-cost strategic approach in confronting this disease.

scholarly journals Gold–Carbon Nanocomposites for Environmental Contaminant Sensing

Micromachines ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 719
Author(s):  
Shahrooz Rahmati ◽  
William Doherty ◽  
Arman Amani Babadi ◽  
Muhamad Syamim Akmal Che Mansor ◽  
Nurhidayatullaili Muhd Julkapli ◽  
...  
Keyword(s):  
Environmental Pollutants ◽  
High Sensitivity ◽  
Environmental Crisis ◽  
World Population ◽  
Chemical Contaminants ◽  
Carbon Nanocomposites ◽  
Minimal Sample ◽  
Wide Range ◽  
And Control ◽  
Analytical Tools

The environmental crisis, due to the rapid growth of the world population and globalisation, is a serious concern of this century. Nanoscience and nanotechnology play an important role in addressing a wide range of environmental issues with innovative and successful solutions. Identification and control of emerging chemical contaminants have received substantial interest in recent years. As a result, there is a need for reliable and rapid analytical tools capable of performing sample analysis with high sensitivity, broad selectivity, desired stability, and minimal sample handling for the detection, degradation, and removal of hazardous contaminants. In this review, various gold–carbon nanocomposites-based sensors/biosensors that have been developed thus far are explored. The electrochemical platforms, synthesis, diverse applications, and effective monitoring of environmental pollutants are investigated comparatively.

Experiences of job demand and control: A study of first line managers in for-profit psychiatric and addiction care

Work ◽  
2021 ◽  
pp. 1-9
Author(s):  
Linda Widar ◽  
Erika Wall ◽  
Sven Svensson
Keyword(s):  
First Line ◽  
Line Managers ◽  
For Profit ◽  
Job Demand ◽  
Organizational Position ◽  
Wide Range ◽  
Line Manager ◽  
Addiction Care ◽  
And Control ◽  
Demand Control

BACKGROUND: The complex position of a first line manager is characterized by heavy workload and contradictory demands. Little is known about how first line managers experience demand and control in their work. OBJECTIVES: The aim of this study was to explore experiences of demand and control among first line managers within psychiatric and addiction care. METHOD: In the present study, interviews with ten managers in for-profit psychiatric and addiction care in Sweden were analyzed with a phenomenographic approach. RESULTS: The managers experiences of demand and control implied varied and extensive responsibilities for a wide range of professions; regulation by organizational, economic, and political frameworks; creating balance in their work; and handling the emergence and consequences of acute crisis. These experiences of demand and control involved high and contradictory demands together with coexisting high and low levels of control. Many of their work characteristics could be described in terms of both demand and control. CONSLUSION: The first line managers experiences of demand and control are more complex than implied by the job demand control theory. Our results suggest that the organizational position and branch should be considered when identifying health hazards in the work environment of first line managers.

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