摘要 :
1. Importance of geophysics in developing BMPs
2. Background on geophysical methods:
2.1 ER, IP and Seismic _
3. Case studies - applications that can relate also to coal ash or CCR management.
摘要 :
1. Importance of geophysics in developing BMPs
2. Background on geophysical methods:
2.1 ER, IP and Seismic _
3. Case studies - applications that can relate also to coal ash or CCR management.
摘要 :
The Elkhead Reservoir Enlargement Project begins and ends as a story of opportunity and cooperation. The story is one of unlikely partnerships between a state wildlife agency and a coal fired power plant; between ranchers and enda...
展开
The Elkhead Reservoir Enlargement Project begins and ends as a story of opportunity and cooperation. The story is one of unlikely partnerships between a state wildlife agency and a coal fired power plant; between ranchers and endangered fish; and between Federal, state, and local governments.
收起
摘要 :
The Elkhead Reservoir Enlargement Project begins and ends as a story of opportunity and cooperation. The story is one of unlikely partnerships between a state wildlife agency and a coal fired power plant; between ranchers and enda...
展开
The Elkhead Reservoir Enlargement Project begins and ends as a story of opportunity and cooperation. The story is one of unlikely partnerships between a state wildlife agency and a coal fired power plant; between ranchers and endangered fish; and between Federal, state, and local governments.
收起
摘要 :
This paper assesses the accuracy and convergence of the bond-based Peridynamic model with brittle failure, known as the prototype micro-brittle (PMB) model. We investigate the discrete equations of this model, suitable for numeric...
展开
This paper assesses the accuracy and convergence of the bond-based Peridynamic model with brittle failure, known as the prototype micro-brittle (PMB) model. We investigate the discrete equations of this model, suitable for numerical implementation. It is shown that the widely used discretization approach incurs rather large errors. Motivated by this observation, a correction is proposed, which significantly increases the accuracy by cancelling errors associated with the discretization. As an additional result, we derive equations to treat the interactions between differently sized particles, i.e., a non-homogeneous discretization spacing. This presents an important step forward for the applicability of the PMB model to complex geometries, where it is desired to model interesting parts with a fine resolution (small particle spacings) and other parts with a coarse resolution in order to gain numerical efficiency. Validation of the corrected Peridynamic model is performed by comparing longitudinal sound wave propagation velocities with exact theoretical results. We find that the corrected approach correctly reproduces the sound wave velocity, while the original approach severely overestimates this quantity. Additionally, we present simulations for a crack growth problem which can be analytically solved within the framework of Linear Elastic Fracture Mechanics Theory. We find that the corrected Peridynamics model is capable of quantitatively reproducing crack initiation and propagation.
收起
摘要 :
This paper assesses the accuracy and convergence of the bond-based Peridynamic model with brittle failure, known as the prototype micro-brittle (PMB) model. We investigate the discrete equations of this model, suitable for numeric...
展开
This paper assesses the accuracy and convergence of the bond-based Peridynamic model with brittle failure, known as the prototype micro-brittle (PMB) model. We investigate the discrete equations of this model, suitable for numerical implementation. It is shown that the widely used discretization approach incurs rather large errors. Motivated by this observation, a correction is proposed, which significantly increases the accuracy by cancelling errors associated with the discretization. As an additional result, we derive equations to treat the interactions between differently sized particles, i.e., a non-homogeneous discretization spacing. This presents an important step forward for the applicability of the PMB model to complex geometries, where it is desired to model interesting parts with a fine resolution (small particle spacings) and other parts with a coarse resolution in order to gain numerical efficiency. Validation of the corrected Peridynamic model is performed by comparing longitudinal sound wave propagation velocities with exact theoretical results. We find that the corrected approach correctly reproduces the sound wave velocity, while the original approach severely overestimates this quantity. Additionally, we present simulations for a crack growth problem which can be analytically solved within the framework of Linear Elastic Fracture Mechanics Theory. We find that the corrected Peridynamics model is capable of quantitatively reproducing crack initiation and propagation.
收起
摘要 :
A semiotic approach to the design space of information presentation is presented in which Formal Concept Analysis (FCA) is used to represent and explore attributes of abstract sign types and the media (graphical, haptic, acoustic,...
展开
A semiotic approach to the design space of information presentation is presented in which Formal Concept Analysis (FCA) is used to represent and explore attributes of abstract sign types and the media (graphical, haptic, acoustic, gestic) through which they are presented as specific representational forms. Early taxonomies in design have typically been incomplete (in only considering graphics) and inconsistent (in the absence of separation between media and sign types). With digital multimedia and the future "semantic web", we need a consistent taxonomy to support component-based flexible (adaptive, tailorable) presentations with a clear separation between (a) the content forms of data, (b) the representational forms through which data is expressed, (c) the combination of media of presentation, and (d) the specific layout within the constraints of the presentation devices and the ergonomic and aesthetic choices of designers and users.
收起
摘要 :
A semiotic approach to the design space of information presentation is presented in which Formal Concept Analysis (FCA) is used to represent and explore attributes of abstract sign types and the media (graphical, haptic, acoustic,...
展开
A semiotic approach to the design space of information presentation is presented in which Formal Concept Analysis (FCA) is used to represent and explore attributes of abstract sign types and the media (graphical, haptic, acoustic, gestic) through which they are presented as specific representational forms. Early taxonomies in design have typically been incomplete (in only considering graphics) and inconsistent (in the absence of separation between media and sign types). With digital multimedia and the future “semantic web”, we need a consistent taxonomy to support component-based flexible (adaptive, tailorable) presentations with a clear separation between (a) the content forms of data, (b) the representational forms through which data is expressed, (c) the combination of media of presentation, and (d) the specific layout within the constraints of the presentation devices and the ergonomic and aesthetic choices of designers and users.
收起
摘要 :
A semiotic approach to the design space of information presentation is presented in which Formal Concept Analysis (FCA) is used to represent and explore attributes of abstract sign types and the media (graphical, haptic, acoustic,...
展开
A semiotic approach to the design space of information presentation is presented in which Formal Concept Analysis (FCA) is used to represent and explore attributes of abstract sign types and the media (graphical, haptic, acoustic, gestic) through which they are presented as specific representational forms. Early taxonomies in design have typically been incomplete (in only considering graphics) and inconsistent (in the absence of separation between media and sign types). With digital multimedia and the future "semantic web", we need a consistent taxonomy to support component-based flexible (adaptive, tailorable) presentations with a clear separation between (a) the content forms of data, (b) the representational forms through which data is expressed, (c) the combination of media of presentation, and (d) the specific layout within the constraints of the presentation devices and the ergonomic and aesthetic choices of designers and users.
收起
摘要 :
Due to the increasing availability of drones, collisions between privately piloted drones and aircraft are becoming increasingly probable. It is commonly accepted, that during a collision, drones pose a higher threat to the aircra...
展开
Due to the increasing availability of drones, collisions between privately piloted drones and aircraft are becoming increasingly probable. It is commonly accepted, that during a collision, drones pose a higher threat to the aircraft than birds of the same mass due to the higher strength and stiffness. This manuscript presents experimental data recorded during quasi-static and high velocity impact experiments with critical components of the DJI Mavic 2 Zoom. Due to their high mass, strength and stiffness, the batteries were found to be the most critical component of a drone. The motors had higher strength and stiffness than the batteries, but due to their low weight (only about 10% of the battery), the motors are considered less critical. Cameras were deemed uncritical due to low strength, stiffness and mass. Under high velocity impact, the batteries showed a fluid-type flow behavior which has not yet been reported before and which might guide future simulation work for drone impact scenarios.
收起
原文获取