Elastic objects across a wide range of scales deform under local changes of their intrinsic properties, yet the shapes are glocal, set by a complicated balance between local properties and global geometric constraints. Here, we explore this interplay during the inversion process of the green alga Volvox, whose embryos must turn themselves inside out to complete their development. This process h...

Seismic impedance inversion is an important method to identify the spatial characteristics of underground rock physical properties. results and uncertainty evaluation are scientific basis for risk decision-making in oil gas development. Under assumption that error observed seismic data meet Gaussian distribution or log–Gaussian distribution, Bayesian linear can analytically obtain posterior pro...

Exoskeletons that enhance human strength, endurance, and speed while being transparent to the wearer are feasible. In order to be transparent, the exoskeleton must determine the user’s intent, apply forces when and where appropriate, and present low impedance to the wearer. We present a one degree of freedom exoskeleton called the RoboKnee which achieves a high level of transparency. User inten...

Seismic exploration is one of the main geophysical methods to extract quantitative inferences about the Earth’s interior at different scales from the recording of seismic waves near the surface. Main applications are civil engineering for cavity detection and landslide characterization, site effect modelling for seismic hazard, CO2 sequestration and nuclearwaste storage, oil and gas exploration...

Detecting karstification processes in hydrocarbon carbonate reservoirs is important because of their porosity, permeability and also the risk associated with their drilling. A very useful technique to locate buried karsts is 3D seismic. In this research, seismic frequency decomposition (spectral decomposition) and seismic inversion techniques used to identify these sub-surface diagenetic featur...

We collected SH-wave seismic reflection data over a shallow aquifer in southwestern British Columbia to investigate the use of such data in hydrogeologic applications. We used this data set in developing a methodology that uses cone penetrometer data as an integral part of the inversion and interpretation of the seismic data. A Bayesian inversion technique converts the seismic amplitude variati...

We present a hydro-elastic actuator that has a linear spring intentionally placed in series between the hydraulic piston and actuator output. The spring strain is measured to get an accurate estimate of force. This measurement alone is used in PI feedback to control the force in the actuator. The spring allows for high force fidelity, good force control, minimum impedance, and large dynamic ran...

Over the past two decades, a variety of micropumps have been explored for various applications in microfluidics such as control of picoand nanoliter flows for drug delivery as well as chemical mixing and analysis. We present the fabrication and preliminary experimental studies of flow performance on the micro impedance pump, a previously unexplored method of pumping fluid on the microscale. The...

I grant The Pennsylvania State University the non-exclusive right to use this work for the University's own purposes and to make single copies of the work available to the public on a not-for-profit basis if copies are not otherwise available. ______________________ Tin-Wai Lee iii ABSTRACT Time-lapse (4D) inversion is a stand-alone method that does not require prior time-lapse seismic processi...

This study reports the effects of ankle muscle fatigue on ankle mechanical impedance. It suggests that decreasing ankle impedance with muscle fatigue may contribute to an increased probability of ankle injury. If confirmed, this observation may have important athletic, military and clinical implications. The experiment was designed to induce fatigue in the tibialis anterior and triceps surae mu...