scholarly journals Analysis of support system for a conveyance tunnel in the higher Himalayan zone: A case study on Upper Tamakoshi HEP, Nepal

2021 ◽  
Vol 4 (1) ◽  
pp. 90-97
Author(s):  
Kalyan Paudyal
Keyword(s):  
Numerical Modeling ◽  
Stress Concentration ◽  
Support System ◽  
Empirical Method ◽  
Vital Role ◽  
Site Specific ◽  
Specific Data ◽  
Overburden Thickness ◽  
The Stability

After excavation, insitu stress conditions are changed which lead deformation due to the stress concentration. For the stability in the excavated tunnel profile, appropriate support system is essential. To recommend the support system, site specific data are used from Higher Himalayan Region of Nepal. Study is focused on 3 m and 6 m size inverted D Shaped tunnel with three different overburden thickness. For the analysis of support system: Empirical method, Analytical method and Numerical Modeling are performed. Result obtained from the different approaches for three different overburden heights as well as for both size tunnels are compared and finally required support system is recommended. It was found significant change in deformations while increase in size of tunnel. Overburden thickness is also playing the vital role in this parameter but size effect is more prominent.

Numerical modeling of an umbrella arch as a pre-support system in difficult geological conditions: a case study

2015 ◽  
Vol 75 (1) ◽  
pp. 211-221 ◽  
Author(s):  
Ayub Elyasi ◽  
Mohammad Javadi ◽  
Taher Moradi ◽  
Javad Moharrami ◽  
Saeid Parnian ◽  
...  
Keyword(s):  
Numerical Modeling ◽  
Support System ◽  
Geological Conditions ◽  
Umbrella Arch

Science-Based Innovation in China: A Case Study of Artemisinin from Laboratory to the Market

2018 ◽  
Vol 03 (02) ◽  
pp. 1850011 ◽  
Author(s):  
Zhang Qingzhi ◽  
Yang Yacheng ◽  
Qi Yaoyuan ◽  
Lei Jiasu
Keyword(s):  
Clinical Medicine ◽  
New Technology ◽  
Innovation Process ◽  
Vital Role ◽  
Multidisciplinary Research ◽  
Research Teams ◽  
Research Involvement ◽  
Corporate Funding ◽  
The Stability

Science-based innovation emerged from novel and discontinuous innovations which provoked irreversible yet significant changes in science and technology. This research investigated the commercialization process of artemisinin, a typical science-based innovation in China. Due to her research involvement with artimisinin (qinghaosu), Tu Youyou received the 2011 Lasker Award in clinical medicine and the 2015 Nobel Prize in Physiology or Medicine jointly with William C. Campbell and Satoshi Ōmura. In this paper, the authors reviewed the process of artemisinin’s innovation from labs in a research institute to its entrance into the market. Based on the research, we reached the following conclusions. First, during the process of science-based innovation, a “new technology platform” might be established and a series of applications might be invented. Second, the extensive cooperation among research institutions and companies played a vital role in the science-based innovation. Third, the science-based innovation emerged through multidisciplinary research teams as well as contacts among scientists with cross-fields expertise. Fourth, for science-based innovation, early research funding mainly relied on public funds. During the commercialization stage, corporate funding plays a major role. Fifth, a clear research objective, an overall planning, coordination, and the stability of policies were also important factors in the entire science-based innovation process.

Simulations and Outputs

Radiocarbon ◽  
2014 ◽  
Vol 56 (2) ◽  
pp. 871-876 ◽  
Author(s):  
Seren Griffiths
Keyword(s):  
Material Culture ◽  
Data Selection ◽  
Multiple Model ◽  
Site Specific ◽  
Specific Data ◽  
Cultural Traits ◽  
Site Chronology ◽  
A Site ◽  
Regional Analyses

Bayesian analysis is now routinely applied for the construction of site-specific stratigraphic chronological models. Other approaches have analyzed the chronology of phases of archaeological activity across regions. The available radiocarbon results—the nature of the samples and their associations—provide the basis for what chronological questions it is possible to address for any site or region. In dealing with regional analyses, due consideration must be made of data selection. While data selection might be a relatively self-evident consideration in the analysis of a site chronology, working with data from a larger region poses a number of specific data selection issues. Robust association between dated samples and a particular type of diagnostic material culture or site may provide one means of producing regional chronologies. However, if the activity under investigation includes a number of different cultural traits, which are related but with each having a slightly different chronological currency, defining the temporal end of data selection becomes more problematic. This article presents one approach, using a case study from the British Mesolithic-Neolithic transition, with 880 simulation OxCal models used to investigate the effect of variously defining the end of a regional archaeological phase. The results emphasize that for a regional case study, sensitivity analysis may provide a useful tool to ensure representative models; the study also highlights the importance of comparing multiple model posteriors.

Simulations and Outputs

Radiocarbon ◽  
2014 ◽  
Vol 56 (02) ◽  
pp. 871-876
Author(s):  
Seren Griffiths
Keyword(s):  
Material Culture ◽  
Data Selection ◽  
Multiple Model ◽  
Site Specific ◽  
Specific Data ◽  
Cultural Traits ◽  
Site Chronology ◽  
A Site ◽  
Regional Analyses

Bayesian analysis is now routinely applied for the construction of site-specific stratigraphic chronological models. Other approaches have analyzed the chronology of phases of archaeological activity across regions. The available radiocarbon results—the nature of the samples and their associations—provide the basis for what chronological questions it is possible to address for any site or region. In dealing with regional analyses, due consideration must be made of data selection. While data selection might be a relatively self-evident consideration in the analysis of a site chronology, working with data from a larger region poses a number of specific data selection issues. Robust association between dated samples and a particular type of diagnostic material culture or site may provide one means of producing regional chronologies. However, if the activity under investigation includes a number of different cultural traits, which are related but with each having a slightly different chronological currency, defining the temporal end of data selection becomes more problematic. This article presents one approach, using a case study from the British Mesolithic-Neolithic transition, with 880 simulation OxCal models used to investigate the effect of variously defining the end of a regional archaeological phase. The results emphasize that for a regional case study, sensitivity analysis may provide a useful tool to ensure representative models; the study also highlights the importance of comparing multiple model posteriors.

scholarly journals Support System Design for Deep Coal Mining by Numerical Modeling and a Case Study

2021 ◽  
Author(s):  
Shankar Vikram ◽  
Dheeraj Kumar ◽  
Duvvuri Satya Subrahmanyam
Keyword(s):  
Numerical Modeling ◽  
Boundary Conditions ◽  
System Design ◽  
Coal Mining ◽  
Support System ◽  
Modeling Technique ◽  
Mine Design ◽  
Godavari Valley

Importance of numerical modeling in mine design gained pace after modern way of approach took birth through many variants. Methods such as Continuum and Discontinuum emerge as most effective in resolving certain issues. Cases such as heterogeneity, prevailing boundary conditions in continuum case and presence of discontinuities in other have provided solutions for many causes. A suitable support system is designed for deep virgin coal mining blocks of Godavari Valley Coalfield in India. This analysis is carried out using numerical modeling technique. The results show that the stresses at an angle to the level galleries are adverse. The level gallery/dip-raise may be oriented at 200 to 400 to reduce roof problems.

scholarly journals Numerical Analysis of the Width Design of a Protective Pillar in High-Stress Roadway: A Case Study

2021 ◽  
Vol 2021 ◽  
pp. 1-18
Author(s):  
FuZhou Qi ◽  
ZhanGuo Ma ◽  
Ning Li ◽  
Bin Li ◽  
Zhiliu Wang ◽  
...  
Keyword(s):  
Numerical Modeling ◽  
Energy Density ◽  
Large Deformation ◽  
High Stress ◽  
Vertical Stress ◽  
Pillar Width ◽  
Modeling Approach ◽  
Roadway Stability ◽  
The Stability

The width design of protective pillars is an important factor affecting the stability of high-stress roadways. In this study, a novel numerical modeling approach was developed to investigate the relationship between protective pillar width and roadway stability. With the 20 m protective pillar width adopted in the field test, large deformation of roadways and serious damage to surrounding rocks occurred. According to the case study at the Wangzhuang coal mine in China, the stress changes and energy density distribution characteristics in protective pillars with various widths were analysed by numerical simulation. The modeling results indicate that, with a 20 m wide protective pillar, the peak vertical stress and energy density in the pillar are 18.5 MPa and 563.7 kJ/m3, respectively. The phenomena of stress concentration and energy accumulation were clearly observed in the simulation results, and the roadway is in a state of high stress. Under the condition of a 10 m wide protective pillar, the peak vertical stress and energy density are shifted from the pillar to roadway virgin coal region, with peak values of 9.5 MPa and 208.3 kJ/m3, respectively. The decrease in vertical stress and energy density improves the stability of the protective pillar, resulting in the roadway being in a state of low stress. Field monitoring suggested that the proposed 10 m protective pillar width can effectively control the large deformation of the surrounding rock and reduce coal bump risk. The novel numerical modeling approach and design principle of protective pillars presented in this paper can provide useful references for application in similar coal mines.

scholarly journals Solar Equipment Based Micro Grid in Hilly Terrains of Rural India - A Broad Perspective

2020 ◽  
Vol 10 (2) ◽  
pp. 26-35
Author(s):  
Archan Bhanja ◽  
Anil Kumar ◽  
Anshuman Gupta
Keyword(s):  
Rural Areas ◽  
Vital Role ◽  
Rural Electrification ◽  
Broad Perspective ◽  
Essential Requirement ◽  
Micro Grid ◽  
The Government ◽  
The Stability ◽  
Micro Grids

Rural electrification is an essential requirement for improving the lives of people residing in rural areas and improving their image among the international community. To install Photo Voltaic (PV) panels in isolated regions as per government plans and regulations, solar-based micro grids are needed for Efficiency in the Energy Sector. There are many components required for installing and operating a micro grid. In addition, the location of the micro grid also plays a vital role in the installation. To analyze the difficulties and challenges, especially in hilly terrains, a detailed review of the factors involved in installation of solar-based micro grid is carried out. The general challenges involving the technical difficulties such as the stability, reliability, power imbalance, control and operation are presented in this paper. Stand-alone models of micro grids are described along with its advantages. The government initiatives like subsidies and funding for rural electrification is discussed. As a case study, two micro grids in India, one at Ladakh and one at west Bengal are presented. These case studies bring out the problems and issues faced during the rural electrification and recommendations were given for the future scope.

A Physical and Numerical Modeling for Launching of Jackets (Case Study on Balal PLQ Platform)

2008 ◽  
Vol 130 (3) ◽  
Author(s):  
M. R. Honarvar ◽  
Moharam D. Pirooz ◽  
Mohammad R. Bahaari
Keyword(s):  
Numerical Modeling ◽  
Physical Modeling ◽  
Oil Field ◽  
Physical Models ◽  
Lower Viscosity ◽  
The Difference ◽  
The Stability ◽  
Stability Of Structures ◽  
Similarity Laws

Platform structures are commonly utilized for various purposes including offshore drilling, processing, and support of offshore operations. A jacket is a supporting structure for deck facilities, stabilized by piles driven through it to the seabed. In a jacket design, operational and environmental loads are very important and must be intensively investigated to secure the stability of structures during their service life, as well as installation phase. The main purpose of this research is to evaluate the results of physical modeling for the launch operation of jackets from barge into the sea, as the most hazardous stage in the installation of a platform, and compare them to those of numerical modeling. Both physical and numerical modeling parameters are described and they are examined on a prototype platform, i.e., Balal oil field production and living quarter platform that is a 1700 tone, eight-legged jacket located in the center of Persian Gulf, some 100km distance from Iranian Lavan Island. It is found that both numerical and physical methods can describe the motion of the barge similarly well, but some differences are traced in the motion of jacket. The inequalities are, then, appeared to be due to the Froude-type parameters applied for modeling purpose. One notable fact investigated in this research is the necessity for choosing Reynolds–Froude type in the physical modeling of the launch, instead of Froude type. This is because, in addition to the importance of gravitational and inertial forces, the viscosity affects the drag hydrodynamic force, as well. It should be noted that viscosity and consequently drag coefficient in Froude type modeling cannot be quite applicable and this causes the difference observed between the results of physical and numerical modeling. Although there have been so many jacket launching designed and probably their physical models have been tested, but to the best of our knowledge from the literature, there was found no study on Reynolds–Froude physical modeling of jacket launch phenomenon. If one is interested in practicing a Reynolds-Froude physical modeling, it could be done either in a centrifuge test or by using a fluid with lower viscosity dependent on the scale of model, or even by finding a fluid (with new viscosity and new density) and a new gravity to have simultaneously the Froude and the Reynolds similarity laws satisfied.

A Physical and Numerical Modeling for Launching of Jackets: Case Study on Balal PLQ Platform

2007 ◽  
Author(s):  
M. R. Honarvar ◽  
Moharram D. Pirooz ◽  
Mohammad R. Bahari
Keyword(s):  
Numerical Modeling ◽  
Physical Modeling ◽  
Oil Field ◽  
Knowledge Based ◽  
Lower Viscosity ◽  
Operational Life ◽  
The Difference ◽  
The Stability ◽  
Stability Of Structures

Platform structures are commonly utilized for various purposes including offshore drilling, processing and support of offshore operations. A jacket is a supporting structure for deck facilities stabilized by leg piles through the seabed. In a jacket design, operational and environmental loads are very important and must be investigated intensively to secure the stability of structures during their operational life, as well as installation phase. The main purpose of this research is to evaluate and compare the results of physical and numerical modeling for the launch operation of jackets from barge into the sea, as the most hazardous stage in the installation of a platform. Both physical & numerical modeling basics are described and they are performed on Balal PLQ (Production and Living Quarter) platform that is one 8-legged, 1700-tone main jacket of Balal oil field, located in the center of Persian Gulf, some 100 kms distance from Iranian Lavan Island. It is found that both methods can describe the motion of the barge similarly well, but some differences are traced in the motion of jacket. Then, the inequalities are evaluated to be due to the Froude-type parameters chosen for modeling purpose. The most important result achieved in this research is the necessity of choosing Reinolds-Froude type for physical modeling of launching, instead of Froude-type. This is due to the effect of viscosity in drag hydrodynamic force in addition to the importance of gravitational and inertial forces. It should be noted that viscosity and consequently drag coefficient in Froude type modeling is not quite correct and causes the difference between the results of physical and numerical modeling. To our knowledge, based on the surveyed done in the literature, although there was no results found on the physical modeling of jacket launch to be addressed, but it seems that Reynolds-Froude modeling could be done either in a centrifuge test or by using a fluid with lower viscosity dependent on the scale of model.

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