Optical activity inherent in crystalline structures of biopolymers and crystallized polymeric materials can serve a laserless (safe and inexpensive) method of flow illumination to be used in volumetric flow velocimetry. Seeding particles incorporating symmetric crystal colonies (e.g., starch granules, polymer...
In this research we designed and fabricated the first spinning and levitating optical resonator, we also present a record value of quality factor over mode volume. In 1970 that Arthur Ashkin manage to use radiation pressure to make an...
Methyl cellulose hydrogel is a thermo-reversible polymer, that solidifies from its room temperature liquid state with an increase in temperature (inverse freezing). This gel has been shown to be a highly effective shock mitigating material, with potential applications to the...
This research examines the deposition patterns of particles smaller than 2.5 micron in the human lung acinus, which is the deepest region in the lung that includes pulmonary alveoli. These particles move down the airway tree under the influence of...
Mechanical communication between muscles and neurons is essential for proprioception, which is the ability to sense the motion and position of body parts. Proprioception requires the transduction of muscle-generated deformations into sensory neuronal impulses. In proprioceptive organs, the mechanical coupling...
Although samples testing laboratories have high level of automation, it is still not possible to completely exclude a person from samples testing cycle. Laboratory personnel perform many preparatory operations that are too complex for robots. At the same time,...
The thesis considers transtiton from two-dimensional to three-dimensional response (swirling) in a problem of liquid sloshing in a symmetric vessel under external periodic forcing. Such transition is well-known in the vicinity of the primary 1:1 resonance between the lowest eigenfrequency...
In this project the purpose was to develop a medical device, a probe, to conduct an otoscopic test. The test will provide a video imaging of tympanic membrane vibrations and will be used to diagnose hearing problems. The method that...
In the last decades, the car and aviation industries have shown a growing interest in magnesium (Mg) alloys, due to their high specific strength. With that said, the widespread usage of Mg alloys is hindered by their low ductility and strong...
High-Pressure Thermochemical Recuperation is a promising waste heat recovery method that enables utilization of the engine waste heat together with onboard hydrogen production. Our experimental findings showed that this method enables a significant engine efficiency improvement and gaseous emissions...
The study of liquid sloshing in partially filled liquid storage containers has gained significant attention as the seismic vulnerability of these containers represents a potential source of severe environmental accidents: large amplitude sloshing exerts excessive hydrodynamic loads on the container...
Averages are measured in many circumstances for diagnostic, predictive, or surveillance purposes. Examples include: average stress along a beam, average speed along a section of highway, average alcohol consumption per month, average GDP over a large region, a student’s average...
Electro-osmotic flow is a well-established and efficient method for driving microchannel flows that relies on the interaction of an externally applied electric field with charge arising at the interface between the liquid and the channel walls. However, its relatively low...
Many materials such as cellular materials, composites and alloys are heterogeneous, and their microstructure essentially determines their macro-scale mechanical behavior. A good understanding of the macro-scale behavior and the underlying micro-scale mechanism of such materials will be valuable to guide...
We present a novel method for deforming thin liquid-films into desired topographies, driven by a photo actuated thermocapillary effect. Our system consists of a thin liquid film, resting on a flat substrate patterned with an array of metal pads, and...
Wearable and mobile devices, such as smartwatches, smartphones, and wearable medical devices, have become a very important part of our daily life and current trends show they will become even more critical to us in the future. However, almost all...
The important cost reduction, seen for renewable energy technologies, together with the improved conversion efficiency based on new components and materials advances and the appearance of smart-grid technologies has led to a revolution in the energy paradigm. This new energy...
Recently the growing need for quick and reversible attachment in different fields of engineering and technology has led to the development of the new emerging field of adhesion science. This has been essentially inspired by those animals and insects that...
The interfacial thermal resistance, commonly known as Kapitza resistance, is defined as the ratio of discontinuity in the temperature gradient at the two different material interfaces to the heat flux flowing through the interface. In the present work, the Kapitza...
An Absorption Heat Transformer (AHT) is a heat pump which is powered by low-grade (low temperature) heat to produce higher temperature heat. If waste heat is available, an AHT can upgrade it to useful (higher temperature) heat. An AHT...
This work applies the state of the art Computational Fluid Dynamics solver – PyFR to perform GPU accelerated Implicit LES simulations of a NACA 0018 Airfoil with steady and unsteady Active Flow Control and compares results to experiments performed by...
The concept of variation diminishing, i.e., reduction of number of zero-crossing or local extrema, is an elementary property in system and control, optimization and approximation theory. Surprisingly, while the theory behind this concept has been well-established for many decades, it...
A wide variety of fields and applications, such as industrial manufacturing, human machine interfaces and augmented reality depend on the analysis of a real-world data (object, scenes etc.). This information can be collected by 3D scanning devices and consists of...
Analysis and design of sampled-data systems with intermittent feedback is motivated by the contemporary trend to distribute information processing in many networked control applications. In this seminar I will present my research on the stabilization, optimization and implementation of discrete...
The ability to maintain attached air flow over aerodynamic surfaces characterizes the performance of airborne vehicles and sets their operational limits. Stalling of lifting surfaces, characterized by boundary layer separation and typically caused by excessive angles-of-attack or wind gusts,...
Curved structures have been regarded as a benchmark problem for the study of nonlinear structures, presenting a myriad of complex responses, even more so when under the influence of nonlinear, displacement-dependent, electrostatic load. Recently, the focus has gravitated to two-dimensional...
The microcirculation refers to the blood flow through the smallest vessels (> 100 mm), where the delivery of oxygen and nutrients to the tissues takes place. It exists in all tissues and organs except for the cornea. In this seminar,...
Kirchhoff’s law for thermal radiation is one of the few most fundamental thermodynamic principles for radiation. It states that the absorptivity, , and emissivity, , of any material are equal if the material is in thermodynamic equilibrium; . However, at...
Energy delocalization in the attenuation zones of nonlinear oscillatory dynamical systems has been a matter of interest in the engineering fields. Initiation and propagation of discrete breathers (DB) is commonly perceived as the most efficient and ubiquitous delocalization mechanism. However,...
Resonators are an essential building block in sensors, oscillators and filters. Traditionally, microscale resonators have been implemented in electronic circuits, but recently MEMS resonators are becoming increasingly prevalent, due to their higher quality-factor and superior performance. In this research we...
Cell motility is central to processes such as wound healing, immune cell surveillance, and embryonic development. Motility requires the conversion of chemical to mechanical energy. An active area of research is to create motile particles, such as microswimmers, using catalytic...
Internal Combustion (IC) engines have been facing severe criticism for their pollutant and greenhouse gas emissions and overall low thermal efficiency. Although modern, state-of-the-art IC engines are relatively clean and efficient, they face dire competition with the rising...
Heterostructures combining a thin layer of quantum emitters and planar nanostructures enable custom-tailored photoluminescence in an integrated fashion. Here, we demonstrate a photonic Rashba effect from valley excitons in a WSe2 monolayer, which is incorporated into a photonic crystal slab...
A cryocooler is a device for producing cooling at cryogenic temperatures (typically below 120K). The main uses of cryocoolers include liquefaction of natural gas (LNG) for transportation (Transportation), applications of high-temperature superconductors (Superconductors), storage of biological cells and specimens (Biology)....
Integration of advanced materials in complex structures often requires parameter identification of the material constitutive models. This process, also called update of model parameters, represents a challenge in modelling and optimizing these parameters. Building the best model coefficients is based...
. Liquid sloshing in containers is important in a wide range of engineering applications. For example, it can cause a loss of structural and dynamic stability in fuel tanks, and an ecological disaster due to a structural failure in tanks...
Patient-specific surgical simulations based on medical imaging allow surgeons to plan and practice surgical interventions before conducting surgeries and many studies demonstrate that the simulations can improve surgical outcomes. Researchers have devoted great efforts in recent decades and developed various...
A material’s crack growth resistance depends on its resistance to the creation of new free surfaces, as well as its deformation characteristics, particularly those related to dissipation, which in turn are strongly influenced by the material’s microstructure and the imposed...
The human body is a very efficient system comprised of endless different components that are working together in inspiring coordination and synergy. Recruiting this principle of the natural reach-to-grasp (R2G) movement is the cornerstone of this work towards development...
Release and capture of wind dispersed pollen by pine trees is considered to be an ineffective mechanism. However, since pine trees are one of the most ancient trees on earth, one may ask if pine trees enhanced wind pollination and...
Prediction of the disperse phase breakup and transport under turbulence with wide range of scales is a critical subject in multiphase flow studies. Although significant efforts have been dedicated to quantifying these processes, still no unified theory exists enabling prediction...
Thermal radiation is the electromagnetic radiation emitted by a body at a non-zero temperature. The amount of emitted thermal radiation by a body depends on its temperature, T, and its ability to emit, characterized by the emissivity, ε. This fundamental...
Engineering materials with the ability to control the structure at the atomic level is the heart of modern technology. Devices based on stacked layers of graphene are candidates to form a new family of materials with unique...
Pristine specimens yield plastically under high loads by nucleating dislocations. Since dislocation nucleation is a thermally activated process, the so-called nucleation-controlled plasticity is probabilistic rather than deterministic like in bulk specimens, leading to a temperature-dependent distribution of the yield strength...
Micro-/nano-motors, known also as active particles, have an important role in a broad range of biomedical applications, e.g. drug delivery, lab-on-a-chip immunosensing and environmental applications. These self-propelling particles asymmetrically harvest and consume energy of various sources, including optical, chemical, acoustic,...
Interfacial instabilities develop in a liquid-liquid or liquid-gas interface, due to a growth of interfacial perturbations. These instabilities may be capillary, electrohydrodynamic, magnetic and others. Analysis of flow dynamics with interfacial instability is a fascinating challenge which has been drawing...
The homogeneous charge compression ignition (HCCI) is a promising engine combustion approach enabling high efficiency and ultra-low pollutant emissions. The HCCI method combines the advantages of the Diesel and the Otto cycles while eliminating their drawbacks. The HCCI enables...
Consider these questions: You are designing a device that can result in vast destruction in an aggressive adversarial country, but you are unsure whether that destruction will be military or civilian. However, without this device, the adversary can inflict...
The lecture focuses on annular flow, one of the most important flow regimes in gas-liquid and vapor-liquid two-phase flows in tubes and channels. In the annular flow, a thin liquid film flows adjacent to the channel wall, surrounding a...
The seminar will present experimental numerical and theoretical studies on fluid driven actuation of elastic structures. The seminar is comprised of two parts: The first part will talk about pneumatics in soft robots. Pressurization of gas within embedded channels and...
Plastic deformation of metals at high strain rates is of great importance in a variety of fields such as rapid machining and stamping, automobile and aerospace safety, and defense applications. Modeling plasticity in metals is traditionally considered on the...
תקציר ההרצאה : Standard rigid wings are characterized by substantial drag increase during activation of control surfaces, due to lack of continuity in airfoil geometry at the interface between the control surface and the airfoil. In recent years, shape-morphing airfoils...
