Describes about the principle and working of a general SAW sensor, and also describes about the SAW based wireless microactuator for the biomedical applications
MEMS Approach to Low Power Wearable Gas SensorsMichael Lim
This presentation gives an overview of candidates solid state MEMS structures for wearable monitoring systems. The basic transduction mechanisms and device structures are shown for 5 types: QCM, FBAR, SAW, Cantilever, and CMUT. Finally, the structures are compared for their application into these mobile systems.
Describes about the principle and working of a general SAW sensor, and also describes about the SAW based wireless microactuator for the biomedical applications
MEMS Approach to Low Power Wearable Gas SensorsMichael Lim
This presentation gives an overview of candidates solid state MEMS structures for wearable monitoring systems. The basic transduction mechanisms and device structures are shown for 5 types: QCM, FBAR, SAW, Cantilever, and CMUT. Finally, the structures are compared for their application into these mobile systems.
Guided Wave Ultrasound - Principles and Apllicationssubash_j
This presentation provides a general background on the principles and theory of guided wave ultrasound and its application to inspection of a wide range of structures and materials
This is how we can save many life during any natural calamity like earthquake etc.., or if any building collapse then we can use this system which can detect the heart beats of those who are under the collapsed building.
Acoustic Emission (AE) refers to the generation of transient elastic waves produced by a sudden redistribution of stress in a material. When a structure is subjected to an external stimulus (change in pressure, load, or temperature), localized sources trigger the release of energy, in the form of stress waves, which propagate to the surface and are recorded by sensors. With the right equipment and setup, motions on the order of picometers (10 -12 m) can be identified. Sources of AE vary from natural events like earthquakes and rockbursts to the initiation and growth of cracks, slip and dislocation movements, melting, twinning, and phase transformations in metals. In composites, matrix cracking and fiber breakage and debonding contribute to acoustic emissions. AE’s have also been measured and recorded in polymers, wood, and concrete, among other materials.
Separation of Macromolecules by Their Size: The Mean Span Dimensioncypztm
Size Exclusion Chromatograpphy (SEC, also called GPC) separates polymer molecules by their size in dilute solution, but which size parameter to use has been a matter of debate. This presentation contains a brief summary of our work on this problem.
Guided Wave Ultrasound - Principles and Apllicationssubash_j
This presentation provides a general background on the principles and theory of guided wave ultrasound and its application to inspection of a wide range of structures and materials
This is how we can save many life during any natural calamity like earthquake etc.., or if any building collapse then we can use this system which can detect the heart beats of those who are under the collapsed building.
Acoustic Emission (AE) refers to the generation of transient elastic waves produced by a sudden redistribution of stress in a material. When a structure is subjected to an external stimulus (change in pressure, load, or temperature), localized sources trigger the release of energy, in the form of stress waves, which propagate to the surface and are recorded by sensors. With the right equipment and setup, motions on the order of picometers (10 -12 m) can be identified. Sources of AE vary from natural events like earthquakes and rockbursts to the initiation and growth of cracks, slip and dislocation movements, melting, twinning, and phase transformations in metals. In composites, matrix cracking and fiber breakage and debonding contribute to acoustic emissions. AE’s have also been measured and recorded in polymers, wood, and concrete, among other materials.
Separation of Macromolecules by Their Size: The Mean Span Dimensioncypztm
Size Exclusion Chromatograpphy (SEC, also called GPC) separates polymer molecules by their size in dilute solution, but which size parameter to use has been a matter of debate. This presentation contains a brief summary of our work on this problem.
Electrocardiography is a medical topic that has piqued engineers' curiosity. One of the most essential signals observed in heart patients is the electrocardiogram (ECG). The electrocardiogram, or ECG, is an extremely valuable medical device. The objective of an ECG is to assist clinicians in quickly diagnosing human or animal heart activity and detecting aberrant heart activities. The heart's job is to contract rhythmically, pump blood to the lungs for oxygenation, and then return this oxygenated blood to the rest of the body. The spread of electrical signals created by the heart pacemaker, the Sinoatrial (SA) node, maintains and signals this precise rhythm. Detecting such electrical activity in the heart can aid in the detection of a variety of cardiac problems
Technical details of one of the two first color-flow Doppler two- dimensional real-time cardiac ultrasound systems.
Moving blood flow is displayed in color in real time superimposed on a real-time grayscale anatomical image.
First results from the full-scale prototype for the Fluorescence detector Arr...Toshihiro FUJII
The Fluorescence detector Array of Single-pixel Telescopes (FAST) is a design concept for the next generation of ultrahigh-energy cosmic ray (UHECR) observatories, addressing the requirements for a large-area, low-cost detector suitable for measuring the properties of the highest energy cosmic rays. In the FAST design, a large field of view is covered by a few pixels at the focal plane of a mirror or Fresnel lens. Motivated by the successful detection of UHECRs using a prototype comprised of a single 200 mm photomultiplier-tube and a 1 m2 Fresnel lens system [Astropart.Phys. 74 (2016) 64-72], we have developed a new full-scale prototype consisting of four 200 mm photomultiplier-tubes at the focus of a segmented mirror of 1.6 m in diameter. In October 2016 we installed the full-scale prototype at the Telescope Array site in central Utah, USA, and began steady data taking. We report on first results of the full-scale FAST prototype, including measurements of artificial light sources, distant ultraviolet lasers, and UHECRs.
35th International Cosmic Ray Conference — ICRC2017 18th July, 2017
Bexco, Busan, Korea
this is to present basic functional principles of high frequency x-ray generators. The emphasis is put on physical concepts that determine the engineering solutions to the problem of efficient generation and control of high voltage power required to drive the x-ray tube. The physics of magnetically coupled circuits is discussed first, as a background for the discussion of Study related to high-frequency power transformer design by X-ray Generator.
Polymer Waveguide Based Optical Interconnects for High-Speed On-Board Communi...Jian Chen
Multimode polymer waveguides constitute an attractive technology for use in board-level optical interconnects:
- Theoretical model of bandwidth estimation of MM WGs developed;
- Frequency and time domain measurements on 1 m long spiral waveguides conducted;
- Bandwidth performance of multimode WGs can be enhanced using refractive index engineering, launch conditions, waveguide layout, etc.;
- Record 40 Gb/s NRZ and 56 Gb/s PAM-4 over 1 m long waveguide demonstrated.
Ultrasound color Doppler imaging has been routinely used for the diagnosis of cardiovascular diseases, enabling real-time flow visualization through the Doppler effect. Yet, its inability to provide true flow velocity vectors due to its one-dimensional detection limits its efficacy. To overcome this limitation, various VFI schemes, including multi-angle beams, speckle tracking, and transverse oscillation, have been explored, with some already available commercially. However, many of these methods still rely on autocorrelation, which poses inherent issues such as underestimation, aliasing, and the need for large ensemble sizes. Conversely, speckle-tracking-based VFI enables lateral velocity estimation but suffers from significantly lower accuracy compared to axial velocity measurements.
To address these challenges, we have presented a speckle-tracking-based VFI approach utilizing multi-angle ultrafast plane wave imaging. Our approach involves estimating axial velocity components projected onto individual steered plane waves, which are then combined to derive the velocity vector. Additionally, we've introduced a VFI visualization technique with high spatial and temporal resolutions capable of tracking flow particle trajectories.
Simulation and flow phantom experiments demonstrate that the proposed VFI method outperforms both speckle-tracking-based VFI and autocorrelation VFI counterparts by at least a factor of three. Furthermore, in vivo measurements on carotid arteries using the Prodigy ultrasound scanner demonstrate the effectiveness of our approach compared to existing methods, providing a more robust imaging tool for hemodynamic studies.
Learning objectives:
- Understand fundamental limitations of color Doppler imaging.
- Understand principles behind advanced vector flow imaging techniques.
- Familiarize with the ultrasound speckle tracking technique and its implications in flow imaging.
- Explore experiments conducted using multi-angle plane wave ultrafast imaging, specifically utilizing the pulse-sequence mode on a 128-channel ultrasound research platform.
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
Francesca Gottschalk - How can education support child empowerment.pptxEduSkills OECD
Francesca Gottschalk from the OECD’s Centre for Educational Research and Innovation presents at the Ask an Expert Webinar: How can education support child empowerment?
Palestine last event orientationfvgnh .pptxRaedMohamed3
An EFL lesson about the current events in Palestine. It is intended to be for intermediate students who wish to increase their listening skills through a short lesson in power point.
Model Attribute Check Company Auto PropertyCeline George
In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
TESDA TM1 REVIEWER FOR NATIONAL ASSESSMENT WRITTEN AND ORAL QUESTIONS WITH A...
MS Thesis Defense Presentation
1. Ghulam Destgeer
Particle Separation and Chemical Gradient Control
via
Focused Travelling Surface Acoustic Waves (F-TSAW)
Flow Control Laboratory, Department of Mechanical Engineering
2013.06.10
4. 4
Particle separation
• The isolation and separation of micro
particulate materials in a continuous
flow are required for chemical
syntheses and biological analyses.
• The separation and sorting of cells are
critical in a variety of biomedical
applications including:
i. Diagnostics
ii. Therapeutics
iii. Cell biology
<Lee et al., 2010, Lab Chip> <Daniel et al., 2010, Anal Bioanal Chem>
Huang’s group
Sung’s group
6. 6
Chemical gradient control
• Most methods are capable of
generating linear chemical
gradient profiles in a static
manner.
• Generating pulsatile chemical
gradients in microfluidic devices
has important implications for
the characterization of dynamic
biological and chemical
processes.
• Dynamic temporal control of
chemical gradients is required.
<Ahmed et al., 2013, Lab Chip> <Daniel et al., 2006, Anal. Chem.> <Seidi et al., 2011, Biomicrofluidics>
7. 7
Chemical gradient control by oscillating bubbles
• Chemical solutions:
– Dextran-FITC (stimulant)
– Phosphate buffered saline(buffer)
• Input voltage and frequency:
– 12-16Vpp and 30kHz
<Ahmed et al., 2013, Lab Chip>
8. 8
Objective
• (a) Device schematic (b) Particle separation
• (c) Chemical gradient control and uniform micromixing
• (d) F-TSAW amplitude (e) Fabricated device
14. 14
SAW amplitude calculation
F 𝑇𝑆𝐴𝑊~ (Eac/k2) (kR)6φ 𝑇𝑆𝐴𝑊
E 𝑎𝑐~ u2 f2 ρ
Energy density (Eac) – J/m3
SAW displacement (u) – nm
Frequency (f) – MHz
Density (ρ) – kg/m3
Wave number (k) – (μm)-1
Particle radium (R) – (μm)
Constant (φ)
Contour plots of SAW displacement square (u2) – m2
Top – f =133.3MHz
Bottom – f = 40.0MHz
x
z
16. 16
F-TSAW device design
• Two salient features: (i) unidirectional (ii) focused
• Interdigitated transducer(IDT): Two interlocking
comb-shaped metallic electrodes on top of a
piezoelectric substrate.
• Frequency of applied AC signal = frequency of
SAW (fSAW)
– fSAW = c/λ, c is speed of sound in the piezoelectric
substrate
Maximum energy is
transmitted in the
forward direction.
Very little energy is transmitted
in the backward direction.
SAW
λ
λ/8
λ/43λ/16
SAW
Unidirectional transducer
λλ/4
SAW SAW
IDT
F-TSAW amplitude by
a focusing transducer
26. 26
CAPS-2: Particle trajectory and separation
• Experimental conditions:
– Frequency (f): 133.3MHz (High)
– Input power: 1.36W
– Flow rate (Q): 150μl/h
(6.17mm/s)
– μ-channel cross-section:
150x45μm
– μ-particles diameter: 10, 3μm
• (a) Schematic diagram of a
PDMS microchannel.
• (b-c) Once the TSAW was
turned ON, a distinct
separation distance could be
observed.
• (d) Trajectory followed by a 10
µm particle influenced by
acoustic streaming.
27. 27
CAPS-3: Particle trajectory and separation
• Experimental conditions:
– Frequency: 133.3MHz
– Input power: 225mW
– μ-channel cross-section:
• h x w: 40 x 200 μm
– Flow rate (Q):
• Sample+ Sheath: 25μl/h + 75μl/h = 100μl/h
• Average speed: 3.5mm/s
– μ-particles diameter: 3μm and 10μm
• Left: TSAW OFF, all the particles flowing
together with the laminar flow.
• Right: TSAW ON, larger particles are
pushed towards the opposite wall
resulting in separation
28. 28
Particle separation efficiency
• (a) TSAW OFF: all of the particles are
collected at the same outlet
• (b) TSAW ON: 3µm particles are
collected at same outlet whereas
almost 100% of the 10µm particles
passed through a separate outlet.
(a) (b)
32. 32
CAGG
• Acoustic streaming flow induced
via F-TSAW
• Flow is traced by 1µm polymer
microspheres dispersed in DI
water.
• On smaller particles, drag force is
dominant compared to acoustic
radiation force.
• Three microchannels 150µm x
45µm, 200µm x 40µm and 500µm
x 90µm from left to right,
respectively, are tested.
• Microchannel 500µm x 90µm can
produce strong and large vortices
appropriate for mixing and
gradient control.
F-TSAW
F-TSAW
33. 33
Chemical gradient control and micromixing
• Acoustic streaming flow
– Generate chemical gradient
– Uniformly mix fluids.
• Microchannel
– w×h: 500µm×90µm
• Flow rate: 100µl/h (0.6mm/s)
– Fluid 1: rhodamine: 50µl/h
– Fluid 2: DI water: 50 µl/h
• Power input
– Gradient control: 60–200mW (18–
23dBm)
– Uniform mixing: 800mW (29dBm)
35. 35
Summary
• Four types of devices are tested:
– First three are Cross-type Acoustic Particle Separator (CAPS)
– Fourth is Cross-type Acoustic Gradient Generator (CAGG)
• A single micro-chip is capable to be used as CAPS or CAGG
• Particles are successfully separated with efficiency close to
100%:
– 10μm particles from 3μm and 30μm particles from 10μm
• Particle deflection is plotted against input power which
shows:
– 3μm, 7μm and 10μm are separated
• Low amplitude and high frequency (40 and 133.3MHz) waves
are used.
• Chemical gradient control and uniform mixing is also shown
using F-TSAW without trapping any micro-bubble.
