This paper proposes the development of Raman spectroscopy system which has capabilities to characterize the motion of high frequency MEMS/NEMS and devices without surface feature. Raman spectroscopy is being increasingly used as a technique to characterize such devices to overcome inconveniences of other optical measurement techniques of which include laser vibrometer, stroboscopic imaging, interferometry, electronic speckle pattern interferometry, laser holography and blur synthesis. These techniques are limited in frequency to less than 30 MHz and either requires the measurement to be performed along the line of motion or by utilizing a surface feature. A cantilever beam as the most common basic geometry of MEMS/NEMS devices structure is used to evaluate the basic dynamic parameters of a microstructure. Mode shapes of vibration, natural frequencies and strain maps for such structure within the device is determined by using analytical calculation and finite element analysis. A model of cantilever with large end mass is used to calculate strain components whilst mode shape and natura...
An oscilloscope is a laboratory instrument that commonly used to display and analyze the waveform of electronic signals. This device draws a graph of signal voltage as a function of time. Oscilloscope usually have two-dimensional graph which electrical potential differences represent by Y-axis (vertical) and time represent by X-axis (horizontal). With positive values going upward and negative values going downward (Ask.com, 2014). In any oscilloscope, the horizontal sweep is measured in seconds per division (s/div), milliseconds per division (ms/div), microseconds per division (s/div), or nanoseconds per division (ns/div). The vertical deflection is measured in volts per division (V/div), millivolts per division (mV/div), or microvolts per division (µV/div).
The Electro Magnetic Spectrum Radio Waves Radio waves are made by various types of transmitter, depending on the wavelength. They are also given off by stars, sparks and lightning, which is why you hear interference on your radio in a thunderstorm. Radio waves are the lowest frequencies in the electromagnetic spectrum, and are used mainly for communications. Radio waves are divided into:- [IMAGE]Long Wave, around 1~2 km in wavelength. The radio station "Atlantic 252" broadcasts here.
Andrew Downes and Alistair Elfick, Sensors 2010, 10, 1871-1889; doi: 10.3390/s100301871, Raman Spectroscopy and Related Techniques in Biomedicine.
Hendra, P.; Jones, C.; Warnes, G. “The vibrational behaviour of molecules”, in Fourier Transform Raman Spectroscopy Instrumentation and Chemical Applications; Ellis Horwood Ltd.: Chichester, England, 1991.
Machine tool probes used to measure workpieces on milling machines, machining centers, lathes, turning/milling machine, grinding machines and robot. Whether the business is small, middle or large workpiece is not only aligned but also the geometries are inspected. Machine tool probes are used to inspect the workpiee and reduce the manufacturing time and cost and increase capabilities. Probe types in hexagon metrology of m&h are of several types like infrared, radiowave, production probes along with necessary software and applications support. In this chapter we are going to discuss different models of infrared probes.
The Electron beam lithography process utilises a beam of electrons to create periodic voids on the surface of a resist which will have a negative refractive index at certain wavelengths. The width of electron beam can be adjusted to have a width on the nano-scale, which is necessary for the incident electromagnetic radiation to interact with the metama...
In fabrication micro-sensors and devices micro-electro-mechanical systems (MEMS) provides significant opportunities, which are borrowed it fabrication abilities from semiconductor technology.
“Too often we measure everything and understand nothing.” according to Jack Welch. So the government has decided to take a closer look at high powered Micro waves. In his paper I‘m going to speak to you about high power microwaves, it’s applications, a comparison of two different types, some of the history, and the findings in results of its research. “High power microwaves (HPM) is an imprecise term used by several communities [1]. In the DoD it pertains primarily to the generation of high peak power bursts of narrowband (coherent) electromagnetic radiation spanning” a specific frequency range, according to E. Schamiloglu of Department of Electrical & Computer Engineering, University of New Mexico. Directed energy once only apart of every day scifi television can now be apart of everyday life. Laser pointers used for night gazing, fax machines for work, and checkout product scanners are the norm, but a region of directed energy spectrum that has had much less concentration and interest is high power micro-wave technology radar and communication systems. More specifically “moderate average power, broad-bandwidth,” which is used for longer sustained power release and “active denial technology” which is used for nonlethal crowd control. We see as of late that the government has decided the role of high power microwave technology and its applications should be more for the defense es-abolishment, but there are so many more applications in todays world. In recent years and today the need in the modern battlefield is a “target rich environment” for high power micro-wave weapons. With the exception of the standard explosives knives and guns Nearly all equipment contains some kind of electronics. Recently in the gulf war The average sol...
Current systems are limited by the capability of sensors and actuators, as these are bulkier and less reliable than the microelectronic circuit. In a MEM system the sensors act as the ‘eyes’ and gather data about the environment. The microelectronic circuit, which is the ‘brain’, processes the data and accordingly controls the mechanical systems, the ‘arms’ of the MEMS, to modify the environment suitably. The electronics on the MEMS are manufactured using IC techniques while micro machining techniques are used to produce the mechanical and electromechanical parts.
Of all the pioneers of this industry, none stand out as the primary leader of discovery or development. This competitive environment was an integral part of this field's progress. Not all discoveries were harbored as proprietary. There was a great deal of information that flowed amongst the leading scientists developing this technology. Here are some of the key players and some of their contributions:
Fiber optic SPR sensor has various advantages compared to conventional prism-based SPR sensor such as miniaturization, simplified optical design, remote sensing, high sensitivity due to SPR as well as real-time analysis and online detection [17]. Due to the structural particularity of optical fiber, propagation of light beam within it is very complex. Depend on the past experiences on fiber optic sensor, it was difficult to obtain high reliability and accuracy. Besides, the detection accuracy may decrease due to chromatic dispersion that exists in fiber optic SPR sensors. By using Maxwell’s equation, theoretical analysis of the sensing mechanism and calculation algorithms of all configurations were obtained [18, 19]. Recently, theoretical analysis on effect of the propagation of skew ray which occupies the most part of light beam in fiber optic SPR sensor is neglected [20]. On the other hand, simultaneous analysis of multiple samples has ...
3. The effect of the change of material on the dynamic response on both simply supported and cantilever beam is same.
... the vibrations should be equal to the frequency of the IR in order for the radiation to be absorbed. That would modify the amplitude of the molecular vibrations.
As a graduate student, I will undertake research and coursework in Electrical Engineering to enhance my competencies in this field. I intend to complete my master's degree in order to pursue my doctorate. The research that I am most interested in pursuing at Northeastern University surrounds the optical properties of MEMS devices, and the development of substrate-based fast electro-optical interfaces. My interest in this area stems from my undergraduate study in MEMs development for tri-axial accelerometers.
But vibrations can also be beneficial. For instance, many different types of mining operations rely on sifting vibrations through which different sized particles are sorted using vibrations. In nature, vibrations are also used by all kinds of different species in their daily lives. Orb web spiders, for example, use vibrations in their webs to detect the presence of flies and other insects as they struggle after being captured in the web for food. The reason that mechanical systems vibrate freely is because energy is exchanged between the system’s inertial (masses) elements and elastic (springs) elements. Free vibrations usually cease after a certain length of time because damping elements in systems dissipate energy as it is converted back-and-forth between kinetic energy and potential energy. The role of mechanical vibration analysis should be to use mathematical tools for modeling and predicting potential vibration problems and solutions, which are usually not obvious in preliminary engineering designs. If problems can be predicted, then designs can be modified to mitigate vibration problems before systems are manufactured. Vibrations can also be intentionally introduced into designs to take advantage of benefits of relative mechanical motion and to resonate systems (e.g., scanning microscopy). Unfortunately, knowledge of vibrations in preliminary mechanical designs is rarely considered essential, so many vibration studies are carried out only after systems are manufactured. In these cases, vibration problems must be addressed using passive or active design modifications. Sometimes a design modification may be as simple as a thickness change in a vibrating panel; added thickness tends to push the resonant