Simple models for the complex process of rock blasting

2012 ◽  
pp. 295-302 ◽  
2010 ◽  
Vol 19 (4) ◽  
pp. 459 ◽  
Author(s):  
Stuart Matthews ◽  
Jim Gould ◽  
Lachie McCaw

Fire behaviour prediction requires models of dead fuel moisture that are both accurate and suitable for use for operational applications. The paper investigates two methods of developing a simple operational fine fuel moisture model from a more complex process-based model. The first simple model is a table of fuel moisture predictions for values of air temperature, relative humidity, wind speed and solar radiation. The second model reduces the original model to a single differential equation, which may be used on low-powered computers. The simple models are tested against the output of the original model and against observations from two case studies in dry eucalyptus forest in south-western Australia. The single differential equation model was capable of reproducing the prediction of the process-based model at all times of the day, with mean error (ME) in predictions of –0.1% and mean absolute error (MAE) of 0.6%. The table model performed less well, with ME = –0.7% and MAE = 1.1% at 1500 hours, and ME = –1.2% and MAE = 3.0% at other times of the day.


2011 ◽  
Vol 105-107 ◽  
pp. 1521-1527 ◽  
Author(s):  
Xin Jian Sun ◽  
Jian Sheng Sun

The damage caused by blasting vibration on rock mass is an extremely complex process, and has certain impact on the mechanical properties and bearing capacity of the rock, which will affect the overall stability and safe operation of the construction. Therefore, studying on the damage effect of blasting vibration is very necessary. Taking Laxiwa hydropower station project as a background, the paper computed relative velocity response spectrum using monitoring and measuring blasting velocity as an excitation, then analysis was carried out to study the relationship between the depth of rock blasting and the integral value of relative velocity response spectrum as well as the index of cooperation of the integral value and the blast vibration’s duration time. The results show that using three-parameter (velocity, frequency, duration time) was clearly superior to two-parameter (velocity, frequency) on studying the damage fracture of rock blasting, and two-parameter was better than one-parameter (velocity) by analogy.


2021 ◽  
Vol 2021 ◽  
pp. 1-17
Author(s):  
Bo Wu ◽  
Hualong Li ◽  
Guowang Meng ◽  
Shixiang Xu ◽  
Jinglong Zhang ◽  
...  

Rock mass blasting is a complex process that involves the coupling of both discontinuous and continuous media. This paper aims to reveal the dynamic failure process between adjacent boreholes under an elliptical bipolar linear charge structure using the SPH-FEM (smooth particle hydrodynamics and finite-element method) coupling algorithm numerical simulation method. The numerical simulation results are compared with the existing experimental results, which proves the rationality of the algorithm. According to the numerical simulation results, the shaped jet will first shock the hole wall and form a stress concentration zone that will guide the formation of cracks during the stress wave propagation process. In the case of double-hole blast loading, there is a tendency for cracks coalescence to develop between adjacent boreholes due to the superposition of stresses between the double holes and the increase in damage and plastic strain. The best blasting results will be achieved with this structure when the distance between adjacent holes is 110 cm. Finally, the superiority of elliptical bipolar linear blasting in engineering blasting was verified through field experiments. The results of this study provide a reference for subsequent applications of elliptical bipolar structures in the field of rock blasting.


Author(s):  
Rick L. Vaughn ◽  
Shailendra K. Saxena ◽  
John G. Sharp

We have developed an intestinal wound model that includes surgical construction of an ileo-cecal patch to study the complex process of intestinal wound healing. This allows approximation of ileal mucosa to the cecal serosa and facilitates regeneration of ileal mucosa onto the serosal surface of the cecum. The regeneration of ileal mucosa can then be evaluated at different times. The wound model also allows us to determine the rate of intestinal regeneration for a known size of intestinal wound and can be compared in different situations (e.g. with and without EGF and Peyer’s patches).At the light microscopic level it appeared that epithelial cells involved in regeneration of ileal mucosa originated from the enlarged crypts adjacent to the intestinal wound and migrated in an orderly fashion onto the serosal surface of the cecum. The migrating epithelial cells later formed crypts and villi by the process of invagination and evagination respectively. There were also signs of proliferation of smooth muscles underneath the migratory epithelial cells.


Nature ◽  
2020 ◽  
Vol 589 (7840) ◽  
pp. 26-28
Author(s):  
Kevin C. Ma ◽  
Marc Lipsitch
Keyword(s):  
Big Data ◽  

1997 ◽  
pp. 33-36
Author(s):  
Anatoliy Moskovchuk

Ukraine is the motherland of not only Ukrainians but also of many national minorities with different cultures and traditions. Ukraine is a Christian country in general, with non-Christian and non-Christian religions and confessional currents, along with traditional churches - Orthodox, Catholic, Protestant - rooted and actively developing non-traditional Ukrainian culture and spirituality. In Ukraine there is a complex process of spiritual revival, especially in the intellectual environment. Many are written and talk about the preservation of cultural heritage. Everywhere, monuments of architecture, art, which testify to the generally recognized historical contribution of Christianity to the development of spirituality and morality of the Ukrainian people, are restored. In our eyes, there are changes in social and religious relations.


2014 ◽  
Vol 2 (1) ◽  
pp. 8
Author(s):  
Debbie MacLellan ◽  
Jacqui Gingras ◽  
Daphne Lordly ◽  
Jennifer Brady

This paper explores beginning dietetic practitioners’ perspectives on the process of becoming dietetics professionals through the use of vignettes to illuminate the complex process of professional socialization.  Embedded in these vignettes are three themes related to the socialization process that occurs in the early years of dietetic practice: congruence, resilience, and relationships.  Our findings indicate that new dietitians struggle to develop their dietitian identity.  They feel unprepared for the relational and practice realities of the workplace and find the transition from dietetic intern to dietitian challenging.  They seek many ways to cope including seeking support from others and planning for the future but some consider leaving the profession.  It is important to understand the professional socialization and identity formation processes that occur during the early years of practice to ensure that dietitians feel prepared and supported as they begin their careers.


2016 ◽  
Vol 4 (2) ◽  
pp. 110-125
Author(s):  
George Chatzinakos

This paper seeks to conceptualize the way Thessaloniki is promoting culinary tourism, whilst supporting and building upon local networks; engaging and co-creating an urban experience with its citizens and visitors. The aim of the paper is to suggest a potential framework that can be used as a strategic planning tool for the promotion of culinary tourism in Thessaloniki. In this direction, a food festival is being investigated. The last, is conceived by the organizers as the foundation of the idea of culinary tourism in the city. However, the findings indicate that there is a lack of active participation by the locals and not enough communication among various assets that are associated with the culinary identity of the city. In general, Thessaloniki seems to embody the ongoing struggle of a new destination, which is dealing with the complex process of branding and marketing without having the proper tools and the vital required collaboration between its structural networks. Accordingly, the research provides a lens through which the culinary culture of Thessaloniki can be used as a strategic pillar for stimulating a sustainable way of “consuming” and promoting the city’s identity; enhancing Thessaloniki’s appeal as a culinary destination.


The success of the Program of housing stock renovation in Moscow depends on the efficiency of resource management. One of the main urban planning documents that determine the nature of the reorganization of residential areas included in the Program of renovation is the territory planning project. The implementation of the planning project is a complex process that has a time point of its beginning and end, and also includes a set of interdependent parallel-sequential activities. From an organizational point of view, it is convenient to use network planning and management methods for project implementation. These methods are based on the construction of network models, including its varieties – a Gantt chart. A special application has been developed to simulate the implementation of planning projects. The article describes the basic principles and elements of modeling. The list of the main implementation parameters of the Program of renovation obtained with the help of the developed software for modeling is presented. The variants of using the results obtained for a comprehensive analysis of the implementation of large-scale urban projects are proposed.


1999 ◽  
Vol 1 (1) ◽  
pp. 87-102 ◽  
Author(s):  
R. D. Hinshelwood

This paper describes the organizations that were the earliest attempts to establish psychoanalysis formally in Britain. This process of institutionalization occurred between the years 1910 and 1925. Interest flowered at times in the universities and in the progressive school movement. However these seem to have been more ephemeral developments. It was the clinical and professional interest which demanded the first and most long-lasting base. A complex process of interaction between a number of organizations occurred. Their memberships initially intermingled and overlapped until the British Psycho-Analytical Society was consolidated by the mid-1920s.


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