To clarify some aspects of rock destruction with a disc acting on a high confined tunnel face, a series of tests were carried out to examine fracture mechanisms under an indenter that simulates the tunnel boring machi...To clarify some aspects of rock destruction with a disc acting on a high confined tunnel face, a series of tests were carried out to examine fracture mechanisms under an indenter that simulates the tunnel boring machine (TBM) tool action, in the presence of an adjacent groove, when a state of stress (lateral confinement) is imposed on a rock sample. These tests proved the importance of carefully establishing the optimal distance of grooves produced by discs acting on a confined surface, and the value (as a mere order of magnitude) of the increase of the thrust to produce the initiation of chip formation, as long as the confinement pressure becomes greater.展开更多
The finite volume method has been successfully applied in several engineering fields and has shown outstanding performance in fluid dynamics simulation. In this paper, the general framework for the simulation ofnear-w...The finite volume method has been successfully applied in several engineering fields and has shown outstanding performance in fluid dynamics simulation. In this paper, the general framework for the simulation ofnear-wellbore systems using the finite volume method is described. The mathematical model and the numerical model developed by the authors are presented and discussed. A radial geometry in the vertical plane was implemented so as to thoroughly describe near-wellbore phenomena. The model was then used to simulate injection tests in an oil reservoir through a horizontal well and proved very powerful to correctly reproduce the transient pressure behavior. The reason for this is the robustness of the method, which is independent of the gridding options because the discretization is performed in the physical space. The model is able to describe the phenomena taking place in the reservoir even in complex situations, i.e. in the presence of heterogeneities and permeability barriers, demonstrating the flexibility of the finite volume method when simulating non-conventional tests. The results are presented in comparison with those obtained with the finite difference numerical approach and with analytical methods, if possible.展开更多
Blasting in geological bodies is an industrial process acting in an environment characterized by high uncertainties (natural joints, faults, voids, abrupt structural changes), which are transposed into the process par...Blasting in geological bodies is an industrial process acting in an environment characterized by high uncertainties (natural joints, faults, voids, abrupt structural changes), which are transposed into the process parameters (e.g. energetic transfer to rock mass, hole deviations, misfires, vibrations, fly-rock, etc.). The approach to this problem searching for the "optimum" result can be ineffective. The geological environment is marked out by too many uncertainties, to have an "optimum" suitable to different applications. Researching for "Robustness" in a blast design gives rise to much more efficiency. Robustness is the capability of the system to behave constantly under varying conditions, without leading to unexpected results. Since the geology varies from site to site, setting a robust method can grant better results in varying environments, lowering the costs and increasing benefits and safety. Complexity Analysis (C.A.) is an innovative approach to systems. C.A. allows analyzing the Complexity of the Blast System and the criticality of each variable (drilling, charging and initiation parameters). The lower is the complexity, the more robust is the system, and the lower is the possibility of unexpected results. The paper presents the results obtained thanks to the C.A. approach in an underground gypsum quarry (Italy), exploited by conventional rooms and pillars method by drilling and blasting. The application of C.A. led to a reliable solution to reduce the charge per delay, hence reducing the impact of ground vibration on the surrounding structures. The analysis of the correlation degree between the variables allowed recognizing empirical laws as well.展开更多
The increasingly rapid development of the disciplines of petroleum engineering and petroleum geology has led to new methodologies and interpretation techniques forming new knowledge that should be offered quickly and ...The increasingly rapid development of the disciplines of petroleum engineering and petroleum geology has led to new methodologies and interpretation techniques forming new knowledge that should be offered quickly and efficiently to modern engineers and geologists. This need is equally important for students as well as for young professionals. Access and training to all scientific information is necessary to ensure success in their future careers. Today, e-learning has become a common medium for the management and distribution of on-line educational content. Learning Management Systems (LMSs) were not only developed to handle a large variety of multimedia content that provides an organized knowledge repository used to accelerate access to information and skill acquisition; but, LMSs can also keep detailed statistics on the use of the available material offering a powerful training and educational tool. In this document, the Petroleum Knowledge Tutorial System, an LMS platform offering a variety of online educational and training options to petroleum engineers and geologists, is presented. It was created using Moodle, open- source software that can be used to create on-line courses. The platform covers fundamental educational concepts in a structured way. It follows an optimized "workflow" that can be applied not only to solve a specific exercise but also any similar problem encountered over the course of one's career. The platform was designed to offer a repository of learning material in various forms and to favor user-platform interactions. It can be used for training and evaluation purposes through exercises and problem solving that the user can perform online by using browsing software along with internet access. Special tools were created and implemented on the platform to assist the user in completing a variety of tasks including performing exercises involving calculations with given data and plots of points or lines on graphs without leaving the learning environment. Furthermore, videos with detailed explanations follow each learning module and provide the full solution to every exercise. The LMS automatically keeps a large statistical database including the users' access to activities on the platform that can be exported and further processed to improve the platform functionality and evaluate the users' performance.展开更多
Among the major natural disasters that occurred in 2010,the Haiti earthquake was a real turning point concerning the availability,dissemination and licensing of a huge quantity of geospatial data.In a few days several...Among the major natural disasters that occurred in 2010,the Haiti earthquake was a real turning point concerning the availability,dissemination and licensing of a huge quantity of geospatial data.In a few days several map products based on the analysis of remotely sensed data-sets were delivered to users.This demonstrated the need for reliable methods to validate the increasing variety of open source data and remote sensing-derived products for crisis management,with the aim to correctly spatially reference and interconnect these data with other global digital archives.As far as building damage assessment is concerned,the need for accurate field data to overcome the limitations of both vertical and oblique view satellite and aerial images was evident.To cope with the aforementioned need,a newly developed Low-Cost Mobile Mapping System(LCMMS)was deployed in Port-au-Prince(Haiti)and tested during a five-day survey in FebruaryMarch 2010.The system allows for acquisition of movies and single georeferenced frames by means of a transportable device easily installable(or adaptable)to every type of vehicle.It is composed of four webcams with a total field of view of about 180 degrees and one Global Positioning System(GPS)receiver,with the main aim to rapidly cover large areas for effective usage in emergency situations.The main technical features of the LCMMS,the operational use in the field(and related issues)and a potential approach to be adopted for the validation of satellite/aerial building damage assessments are thoroughly described in the article.展开更多
文摘To clarify some aspects of rock destruction with a disc acting on a high confined tunnel face, a series of tests were carried out to examine fracture mechanisms under an indenter that simulates the tunnel boring machine (TBM) tool action, in the presence of an adjacent groove, when a state of stress (lateral confinement) is imposed on a rock sample. These tests proved the importance of carefully establishing the optimal distance of grooves produced by discs acting on a confined surface, and the value (as a mere order of magnitude) of the increase of the thrust to produce the initiation of chip formation, as long as the confinement pressure becomes greater.
文摘The finite volume method has been successfully applied in several engineering fields and has shown outstanding performance in fluid dynamics simulation. In this paper, the general framework for the simulation ofnear-wellbore systems using the finite volume method is described. The mathematical model and the numerical model developed by the authors are presented and discussed. A radial geometry in the vertical plane was implemented so as to thoroughly describe near-wellbore phenomena. The model was then used to simulate injection tests in an oil reservoir through a horizontal well and proved very powerful to correctly reproduce the transient pressure behavior. The reason for this is the robustness of the method, which is independent of the gridding options because the discretization is performed in the physical space. The model is able to describe the phenomena taking place in the reservoir even in complex situations, i.e. in the presence of heterogeneities and permeability barriers, demonstrating the flexibility of the finite volume method when simulating non-conventional tests. The results are presented in comparison with those obtained with the finite difference numerical approach and with analytical methods, if possible.
文摘Blasting in geological bodies is an industrial process acting in an environment characterized by high uncertainties (natural joints, faults, voids, abrupt structural changes), which are transposed into the process parameters (e.g. energetic transfer to rock mass, hole deviations, misfires, vibrations, fly-rock, etc.). The approach to this problem searching for the "optimum" result can be ineffective. The geological environment is marked out by too many uncertainties, to have an "optimum" suitable to different applications. Researching for "Robustness" in a blast design gives rise to much more efficiency. Robustness is the capability of the system to behave constantly under varying conditions, without leading to unexpected results. Since the geology varies from site to site, setting a robust method can grant better results in varying environments, lowering the costs and increasing benefits and safety. Complexity Analysis (C.A.) is an innovative approach to systems. C.A. allows analyzing the Complexity of the Blast System and the criticality of each variable (drilling, charging and initiation parameters). The lower is the complexity, the more robust is the system, and the lower is the possibility of unexpected results. The paper presents the results obtained thanks to the C.A. approach in an underground gypsum quarry (Italy), exploited by conventional rooms and pillars method by drilling and blasting. The application of C.A. led to a reliable solution to reduce the charge per delay, hence reducing the impact of ground vibration on the surrounding structures. The analysis of the correlation degree between the variables allowed recognizing empirical laws as well.
文摘The increasingly rapid development of the disciplines of petroleum engineering and petroleum geology has led to new methodologies and interpretation techniques forming new knowledge that should be offered quickly and efficiently to modern engineers and geologists. This need is equally important for students as well as for young professionals. Access and training to all scientific information is necessary to ensure success in their future careers. Today, e-learning has become a common medium for the management and distribution of on-line educational content. Learning Management Systems (LMSs) were not only developed to handle a large variety of multimedia content that provides an organized knowledge repository used to accelerate access to information and skill acquisition; but, LMSs can also keep detailed statistics on the use of the available material offering a powerful training and educational tool. In this document, the Petroleum Knowledge Tutorial System, an LMS platform offering a variety of online educational and training options to petroleum engineers and geologists, is presented. It was created using Moodle, open- source software that can be used to create on-line courses. The platform covers fundamental educational concepts in a structured way. It follows an optimized "workflow" that can be applied not only to solve a specific exercise but also any similar problem encountered over the course of one's career. The platform was designed to offer a repository of learning material in various forms and to favor user-platform interactions. It can be used for training and evaluation purposes through exercises and problem solving that the user can perform online by using browsing software along with internet access. Special tools were created and implemented on the platform to assist the user in completing a variety of tasks including performing exercises involving calculations with given data and plots of points or lines on graphs without leaving the learning environment. Furthermore, videos with detailed explanations follow each learning module and provide the full solution to every exercise. The LMS automatically keeps a large statistical database including the users' access to activities on the platform that can be exported and further processed to improve the platform functionality and evaluate the users' performance.
文摘Among the major natural disasters that occurred in 2010,the Haiti earthquake was a real turning point concerning the availability,dissemination and licensing of a huge quantity of geospatial data.In a few days several map products based on the analysis of remotely sensed data-sets were delivered to users.This demonstrated the need for reliable methods to validate the increasing variety of open source data and remote sensing-derived products for crisis management,with the aim to correctly spatially reference and interconnect these data with other global digital archives.As far as building damage assessment is concerned,the need for accurate field data to overcome the limitations of both vertical and oblique view satellite and aerial images was evident.To cope with the aforementioned need,a newly developed Low-Cost Mobile Mapping System(LCMMS)was deployed in Port-au-Prince(Haiti)and tested during a five-day survey in FebruaryMarch 2010.The system allows for acquisition of movies and single georeferenced frames by means of a transportable device easily installable(or adaptable)to every type of vehicle.It is composed of four webcams with a total field of view of about 180 degrees and one Global Positioning System(GPS)receiver,with the main aim to rapidly cover large areas for effective usage in emergency situations.The main technical features of the LCMMS,the operational use in the field(and related issues)and a potential approach to be adopted for the validation of satellite/aerial building damage assessments are thoroughly described in the article.