keystone literature eoc success strategies study guide keystone eoc test review for the pennsylvania keystone end of course assessments
LINK 1 ENTER SITE >>> Download PDF
LINK 2 ENTER SITE >>> Download PDF
File Name:keystone literature eoc success strategies study guide keystone eoc test review for the pennsylvania keystone end of course assessments.pdf
Size: 4834 KB
Type: PDF, ePub, eBook
Category: Book
Uploaded: 9 May 2019, 13:32 PM
Rating: 4.6/5 from 800 votes.
Status: AVAILABLE
Last checked: 1 Minutes ago!
In order to read or download keystone literature eoc success strategies study guide keystone eoc test review for the pennsylvania keystone end of course assessments ebook, you need to create a FREE account.
eBook includes PDF, ePub and Kindle version
✔ Register a free 1 month Trial Account.
✔ Download as many books as you like (Personal use)
✔ Cancel the membership at any time if not satisfied.
✔ Join Over 80000 Happy Readers
keystone literature eoc success strategies study guide keystone eoc test review for the pennsylvania keystone end of course assessmentsAugust 11, 2014CRC PressWhere the content of the eBook requires a specific layout, or contains maths or other special characters, the eBook will be available in PDF (PBK) format, which cannot be reflowed. For both formats the functionality available will depend on how you access the ebook (via Bookshelf Online in your browser or via the Bookshelf app on your PC or mobile device). This topic has recently experienced an explosive growth due to the noninvasive or minimally invasive nature and the cost-effectiveness of photonic modalities in medical diagnostics and therapy. The second edition of the Biomedical Photonics Handbook presents fundamental developments as well as important applications of biomedical photonics of interest to scientists, engineers, manufacturers, teachers, students, and clinical providers.Advanced photonic detection technologies integrating the latest knowledge of genomics, proteomics and metabolomics allow sensing of early disease state biomarkers, thus revolutionizing the medicine of the future. Nanobiotechnology has opened new possibilities for detection of biomarkers of disease, imaging single molecules and in situ diagnostics at the single cell level. In addition to these state-of-the art advancements, the second edition contains new topics and chapters including: It also includes an overview of the topic, an extensive collection of spectroscopic data, and lists of references for further reading. The use of practical examples summarizing real-world examples by scientists and engineers allows a collective look into the current best practices. This book will be valuable to anyone seeking to understand the complexities of designing fiber optic instruments, techniques involved behind analysis, diagnostics nuances and therapeutic modalities. Students and practitioners will learn about the latest tools and techniques used by leading researchers, scientists and engineers. A great compilation of varied research fields in the area of Biophotonics.http://feng-huametal.com/userfiles/how-to-set-up-a-manual-typewriter.xml
- Tags:
- keystone literature eoc success strategies study guide keystone eoc test review for the pennsylvania.
It provides a detailed and up-to-date expert coverage of fundamental concepts and current biomedical photonics techniques and applications.To learn how to manage your cookie settings, please see our. The next sections of the paper will describe light-tissue interactions caused by tissue dispersion, scattering, and absorption properties, including light reflection and refraction, absorption, elastic quasi-elastic and inelastic scattering. The major tissue absorbers and types of elastic scattering, including Rayleigh and Mie scattering, will be presented. Series of Biomaterials and Bioengineering, Imperial College Press, London (2006). Wiley-Interscience, Hoboken, NJ (2003). Press, NY (1987). Press, NY (1998). Elsevier Ltd., Philadelphia (2004). Learn More. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license ( ). This article has been cited by other articles in PMC. Abstract Light has found applications in data transmission, such as optical fibers and waveguides and in optoelectronics. It consists of a series of electromagnetic waves, with particle behavior. Photonics involves the proper use of light as a tool for the benefit of humans. It is derived from the root word “photon”, which connotes the tiniest entity of light analogous to an electron in electricity. Photonics have a broad range of scientific and technological applications that are practically limitless and include medical diagnostics, organic synthesis, communications, as well as fusion energy. This will enhance the quality of life in many areas such as communications and information technology, advanced manufacturing, defense, health, medicine, and energy. The signal transmission methods used in wireless photonic systems are digital baseband and RoF (Radio-over-Fiber) optical communication. Microwave photonics is considered to be one of the emerging research fields.http://kiedyeuro.polska.edu.pl/pub/how-to-set-up-a-manual-sewing-machine.xml The mid infrared (mid-IR) spectroscopy offers a principal means for biological structure analysis as well as nonintrusive measurements. There is a lower loss in the propagations involving waveguides. Waveguides have simple structures and are cost-efficient in comparison with optical fibers. These are important components due to their compactness, low profile, and many advantages over conventional metallic waveguides. Among the waveguides, optofluidic waveguides have been found to provide a very powerful foundation for building optofluidic sensors. These can be used to fabricate the biosensors based on fluorescence. In an optical fiber, the evanescent field excitation is employed to sense the environmental refractive index changes. Optical fibers as waveguides can be used as sensors to measure strain, temperature, pressure, displacements, vibrations, and other quantities by modifying a fiber. For some application areas, however, fiber-optic sensors are increasingly recognized as a technology with very interesting possibilities. In this review, we present the most common and recent applications of the optical fiber-based sensors. These kinds of sensors can be fabricated by a modification of the waveguide structures to enhance the evanescent field; therefore, direct interactions of the measurand with electromagnetic waves can be performed. In this research, the most recent applications of photonics components are studied and discussed. Keywords: light, photon, communications, waveguides, fibers, biosensors 1. Introduction The role of light is significant in our lives today. The importance of light cannot be taken for granted because it is vital to most aspects of our contemporary society. It is used everywhere whether it be building, telecommunication, transportation, entertainment, or clothing. Light has applications in data transmission, such as optical fibers and in optoelectronics.https://labroclub.ru/blog/eico-232-manual It is used in compact disc players where a laser reflecting off of a CD transforms the returning signal into music. It is also used in laser printing and digital photography. Connections between computers and telephone lines are possible with the help of light (fiber-optic cables). It is used in optical fiber lasers, optical fiber interferometers, optical fiber modulators, and sensors. Light consists of a series of electromagnetic waves, with particle behavior under certain circumstances. Light is the range of wavelengths in the electromagnetic spectrum ( Figure 1 ). Open in a separate window Figure 1 The electromagnetic spectrum. Photonics is essentially the science that involves generation of a photon (light), its detection, as well as manipulation via transmission, emission, signal processing, modulation, switching, amplification, and sensing. Most photonics applications, even though they cover all technical applications over the entire electromagnetic spectrum, range from near-infrared light to visible region. The term “photonics” was derived from the root word “photon”, which connotes the tiniest entity of light analogous to an electron in electricity. Just as the electronics revolutionized the 20th century, photonics is doing the same in the 21st century. The term photonics was first used to designate a field of research area responsible for utilizing light to perform tasks that are conventionally related to the traditional sphere of electronics, like telecommunications, information processing, and so on. Studies in the field of potonics began in 1960 after the discovery of lasers. Other progress followed including optical fibers for transmitting information, the laser diode in the 1970s, as well as erbium fiber amplifiers. These developments made the foundation for the industrial revolution in the telecommunications sector during the late 20th century and supplied the internet infrastructure. Although created before the 1980s, the word photonics was used commonly for the first time in the 1980s as network operators of telecommunications embraced fiber-optic data transmission. Photonics came into being when the “IEEE Lasers and Electro-Optics Society” came up with a journal called “Photonics Technology Letters” towards the end of the 18th century. Through the years, until 2001 with the dot-com crash, research was primarily focused on optical fiber telecommunication. Nevertheless, the field of photonics has a broad range of scientific and technological applications. These include chemical and biological sensors, laser manufacturing, medical therapy and medical diagnosis, optical computing and displaying technology. Advancement of photonics is possible due to the current success recorded concerning the development of silicon photonics. Photonics is related to opto-mechanics, electro-optics, quantum electronics and quantum optics. Nevertheless, these fields mean different things to both the scientific as well as the business community. Quantum optics is often concerned with fundamental theoretical research areas. Photonics, on the other hand, deals with applied research and progress. Optoelectronics is used to refer to the circuits or devices consisting of both electrical and optical components. The word “electro-optics” was utilized in the past to specifically relate to nonlinear interactions between electrical and optical devices. Photonics is said to be an “All-Pervasive” technology because it allows unlimited light to travel faster than the electrons that are used in electronic computer chips, which means that optical computers will compute thousands of times faster than any electronic computers because of the physical limitations of electronic conduction. More wavelengths can be packed into an optical fiber to allow an increase in the transmission bandwidth that can be in conventional copper wires. For instance, information processing, telecommunications, light detection, metrology, lighting, spectroscopy, photonic computing, holography, medical field (surgery, vision correction, health monitoring and endoscopy), fighting machinery, visual art, agriculture, laser material processing, robotics, and biophotonics. Similar to the way electronics have been used extensively since the creation of earlier transistors of 1948, the exceptional use of photonics continuously increases. Economically significant uses of photonic devices include fiber optic telecommunications, optical data storage, displays, optical pumping of high-power lasers and laser printing. Medical applications: laser surgery, poor eyesight correction, tattoo removal and surgical endoscopy. Manufacturing processes in industries: involves the use of laser in welding, cutting, drilling, and many surface modification techniques. Building and construction: smart structures, laser range finding, and laser leveling. Space exploration and aviation: including astronomical telescopes. Military operations: command and control, IR sensors, navigation, mine laying, hunt and salvage, and discovery. Metrology: range finding, frequency and time measurements. Photonic computing: printed circuit boards, and quantum computing. Micro-photonics and nanophotonics. In simple terms, photonics is currently solving and addressing the challenges of a modern world. Photonics enhances the quality of life; it safeguards our health, security, and safety, it drives our economic growth, and it creates jobs as well as global effectiveness. Photonics technology enhances the quality of life in many areas. Photodetectors are used to detect light. They can be very slow, as in the case of solar cells that are used in harvesting sunlight energy, or very fast like photodiodes that are very fast and are employed in communications in conjunction with digital cameras. Numerous others centered on quantum, thermal, photoelectric and chemical areas also exist. Open in a separate window Figure 2 Publications and citation trends in Photonics (Source: Thomson Reuters Web of Science). Photonic networks are the backbone of data dissemination, specifically in the modern and upcoming wireless communication systems. Photonic networks continue to gain interest for distribution of data from, say, central location to a remote antenna unit at base stations. Two of the most popular data transmission methods in wireless photonic systems are digital baseband and RoF (Radio-over-Fiber) optical communication. In addition, further emerging fields are opto-atomics, in which there is an integration of both atomic and photonic devices. Opto-atomics applications include precise time-keeping. Opto-mechanics, metrology, and navigation, as well as polaritonics, are different from photonics due to the presence of polarization as the primary carrier of information. Microwave photonics is considered to be an emerging research field. Microwave photonics is an enabling technology for the generation, control, distribution, measurement, and detection of microwave signals. Part of the various functionalities facilitated by photonics, microwave measurements centered on photonics can offer greater performance regarding broad frequency coverage, significant direct bandwidth, high immunity to electromagnetic interference (EMI) and low frequency-dependent loss. Photonic microwave measurements therefore have been widely investigated in recent times. Plasmon lasers are among the categories of optical frequency amplifiers that send strong, penetrating, and guiding superficial plasmons underneath the diffraction walls. The interactions between light energy and matter can be intensely improved by the tightly held electric fields in plasmon lasers. Because they can generate high-intensity nano-scale electromagnetic radiation in a fraction of a second, the modern development of plasmon lasers today has sparked the investigation of nanoscience and technology. The mid-IR spectroscopy offers a principal means for biological structure analysis as well as nonintrusive measurements. For instance, the broad cross-section for absorption allows for the detection of traces of vapors at the order of parts-per-trillion (ppt) as well as parts per- billion (ppb). 4. Structure, Types, and Applications of Optical Fibers Optical fibers are flexible filaments made of very clear glass and can carry information in the form of light from one point to another. They are hair-thin structures formed through the formation of preforms, which are glass rods made into fine threads of glass and secured by plastic coatings. Various vapor deposition processes are employed by fiber manufacturers to draw the preform. The two most important components of optical fibers are the core and the cladding. The “core”, which is the axial part of the optical fiber, is made up of silica glass. The optical fiber core is that area of the fiber where light is transmitted. Sometimes, doping elements are used to modify the fiber refractive index, thereby changing the light velocity through the fiber. The “cladding”, on the other hand, is the layer that surrounds the core completely. The cladding refractive index is less than that of the core. This enables the light inside the core to strike the core-cladding interface at a “bouncing angle”, is confined inside the core by the total internal reflection, and keeps moving in the appropriate direction along the fiber length to a certain point. The cladding is usually surrounded by another layer known as “coating,” which normally is comprised of protective polymer films coated during the process of fiber drawing, before being in contact with any surface. Open in a separate window Figure 3 Structure of optical fiber. The mechanism of the modifications on the fiber surface can be characterized through the transmission spectrum measurement of the fibers. There are so many different possible configurations of fibers corresponding to different application purposes. The most important classification considers fibers as either single-mode fibers and multimode fibers. The concept of application-specific fibers was invented at Bell Laboratories in the mid-1990s, and this is followed by an introduction of fibers designed for network applications. These next designs that are used mainly for signal transmission in communications consist of 10-Gbps laser-optimized multimode fibers (OM3), Zero Water Peak Fiber (ZWPF), Non-Zero Dispersion Fibers (NZDF), and fibers that are specially designed for the marine application. Specially designed fibers, like erbium-doped fibers, and dispersion compensating fibers perform tasks that supplement the transmission fibers. The differences between the different transmission fibers are responsible for variations in the number and range of different wavelengths or pathways via which the light is received or transmitted; this is the distance at which a signal can travel without being amplified or regenerated, and the speed at which this signal can travel. This is due to the higher mass of chalcogenide ions compared to oxygen ions. Examples of these materials can be such as arsenic (As) or germanium (Ge), where the infrared absorption of the materials starts at longer wavelengths. These are available as bare fibers and fiber patch cable and are presenting additional protection and fiber connectors at the end of their length. Recently, scientists are facing many technical challenges with fabricating the kind of fibers with air holes. These have unusual guiding structures and can support new light propagation features applicable to novel photonic devices such as lasers and transmitters. In these two types of fibers, the light leakage is eliminated by implementing a special design of the core and cladding, which allows for a high damage tolerance to withstand damages from other even more intense sources such as continuous-wave CO 2 lasers. Some critical parameters affect the performance of optical fibers transmission systems. These parameters and their specifications vary by fiber type and depend upon the intended use. Two of the more significant parameters of fibers are fiber dispersion and attenuation. Attenuation is the decrease in optical power when it propagates from one place to another. High attenuations affect the distance at which signals can be transmitted. Figure 4 shows the variation in attenuation with wavelengths for a wide range of fiber optic cables. Open in a separate window Figure 4 Attenuation against wavelength transmission windows. Dispersion, on the other hand, is inversely related to the bandwidth and refers to the fiber to carry information. Single-mode fibers are associated with a chromatic dispersion that causes pulse spreading due to the various colors of light passing through the fiber at different speeds. Similarly, multimode fibers are related to the modal dispersion that causes pulse spreading due to the geometry of a multimode fiber core, which allows for the multiple modes lasers to simultaneously separate and propagate at the fiber interface. Multimode fibers are the first fibers to be produced on a commercial scale. They are called multimode fibers just because they allow several modes or rays of light to propagate through the waveguide simultaneously. These types of fibers have a much wider core diameter, when compared to the single-mode fibers, and allow for the higher number of modes. Multimode fibers are easier to couple than single-mode fibers. Multimode fibers can be classified into graded-index and step-index fibers. Graded-index multimode fibers make use of the differences in compositions of the glass inside the fiber core and recompense the different path lengths of the modes. They offer more bandwidth than step index fibers. Step-index multimode fibers were the first cords designed but are too slow regarding most applications because of the dispersion caused by the different path lengths of the various modes. Step-index fibers are barely used in modern telecommunications. Multimode fibers that are employed in communications possess the core size of 50 or 62.5 microns. The big core sizes allow the fibers to support many diagonal electromagnetic modes for a given polarization and frequency. Single-mode fibers enjoy lower fiber attenuation than multimode fibers and retain better reliability of each light pulse because they have no dispersion associated with multiple mode fibers. Hence, data can be transferred over a longer distance. Similar to multimode fibers, the earlier single-mode fibers were commonly characterized as step-index fibers (shown in Figure 5 ), which means the refractive index of the fiber cladding is a step below that of the core rather than graduated as in the case of graded-index fibers. Current single-mode fibers have grown into a more sophisticated design like depressed clad, matched clad, or other mysterious structures. Open in a separate window Figure 5 Multimode and single-mode fibers. The core size of single-mode fibers usually is nine microns. Because only one mode can propagate down the fiber length, the total internal reflection process does not occur; hence, the concept of numerical aperture becomes similar to those of multimode fibers. The numerical aperture of multimode fibers is usually larger than those of single-mode fibers. Imagine rays of light striking a distinct boundary separating an optically less dense medium. A less dense medium is the one with a lower reflection index. At an appropriate incidence angle, these rays rather than passing through will be reflected fully. Prisms in binoculars and camera viewfinders make use of total internal reflection. Optical fiber sensors have been studied for over 40 years. Several concepts have been suggested, and many methods have been established for various parameters as well as for various uses. Commercialization of optical fiber sensors has been carried out successfully. Pressure, temperature, and strain are the extensively investigated parameters, and, for the optical fiber sensors, the Bragg fiber grating sensors are the most widely studied technologies. However, in various applications, optical fiber-based sensors are expected to compete with other existing technologies like electronic-based systems. To get attention, since customers are already familiar with the current technologies, there is a need to demonstrate the superior qualities of optical fiber-based sensors over other contemporary methods. Usually, customers are not interested in the procedures involved in the detection. However, these clients only desire sensors with excellent performance at reasonable costs. Therefore, optical fiber-based sensors should be obtainable in the form of a system that includes signal detection and signal processing. 5. Classification of Optical Fiber Sensors There have been some approaches to the classification of optical fiber sensors. The increasing complexity of several types of optical fiber sensors is what prompted the development of adequate and appropriate classification systems. Factors such as physical quantity transduced by the sensors, detection systems, as well as sensor type have been considered in so many classifications. To develop the most suitable classification scheme for optical fiber sensors, an emphasis is given to the most important aspects and, hence, a classification method is adopted. With the continuous increase in the development of optical fiber sensors, so many classification systems that were adopted previously became unsuitable. Hence, factors like wavelength, intensity, phase, and polarization were regarded as the primary classification standards. The disadvantage of this type of classification, however, is that the technique used is given emphasis rather than the sensor itself. This may be insignificant in applications where the most suitable technology is targeted for measuring a parameter of interest like pressure or temperature. However, this approach is also associated with some disadvantages when applied in a similar way to the other methods of measuring various parameters like displacement. Extrinsic sensors are those in which the fiber guides the light wave, and the interaction between the magnitude of the parameter measured and light occurs outside the fiber. These types of sensors have been used successfully for some applications. For intrinsic sensors, on the other hand, interactions between light and the measured parameter occur inside the fiber. Open in a separate window Figure 7 Schematic comparison between ( a ) extrinsic and ( b ) intrinsic sensors An important parameter to be considered in intrinsic sensors is the nature of the optical guidance of the fiber—that is, whether it is multimode, single, or otherwise. The simplest sensors are those that vary the light intensity because they require only a simple detector and source of light. Intrinsic sensors can offer distributed detection for comprehensive coverage. An optical fiber that has a temporary loss, which depends on temperature, can be used to measure temperature. This measurement can be possible by analyzing the Raman scattering of the optical fiber. Nonlinear optical effects that can change the light polarization, which depends on electric field or voltage, can be used in sensing electrical voltage. Other optical fibers have applications in sonar and seismic detection. Examples of these types of fibers are hydrophones. Oil industries, as well as the navy in some countries, make use of the hydrophones systems. Microphone systems that involve the use of optical fibers have been developed by Sennheiser (Germany). In applications where high electric or magnetic fields are required, optical fiber based headphones and microphones are very useful. These types of applications very much require optical fiber sensors since they can withstand very high temperatures compared to the semiconductor sensors. Optical fiber sensors can be used for interferometric sensings such as fiber optic gyroscopes, which are utilized for navigation in some cars and the Boeing 767 aircraft (USA). Optical fibers are used in making hydrogen sensors. Sensors based on Fiber Bragg grating are also very suitable for remote sensing. Fiber optic sensors that are based on Fiber Bragg grating improve performance, productivity, and protection in some manufacturing processes. Integration of Fiber Bragg grating technology enables sensors to offer full investigation and complete information on insights with precise resolution. These types of sensors are normally used in various industries such as aerospace, automotive, telecommunication, and energy. Fiber Bragg gratings are sensitive to mechanical tension, static pressure, and compression and changes in fiber temperatures. The structure of the side-polished fibers (SPFs) has a cladding section that is partially removed on one side; therefore, by modification of the cladding, the evanescent field of the propagating light within the core can interact with surrounding materials that present different refractive indices. We can illustrate the setup of the fiber modification as shown in Figure 3. In this case, a single mode fiber type that is known as SMF-28 is used for the fabrication, where it should be tightly suspended above the polishing wheel when the polishing process starts. The polishing section is only a few centimeters. Therefore, the SMF-28, which is striped, is suspended over the polishing wheel as illustrated in Figure 8. The double-sided scotch tape is wrapped around a shaft of the DC motor. Therefore, the silicon carbide paper sticks to the double-sided scotch tape to create the uniform polishing wheel in such a way that it is perpendicular to the suspended SMF-28 ( Figure 9 ). The position of the polisher should be adjusted to create the contact between the fiber and the wheel. Figure 9 shows the experimental fabrication of the SPF. Open in a separate window Figure 9 Polisher design setup; ( a ) the stage used to hold the fiber; and ( b ) the polishing process, where the light is figuring out from the fiber due to a removal of the cladding. 5.2. Extrinsic Optical Fiber Sensors This type of fiber optic sensor makes use of optical fiber cables, usually the multimode type, to pass controlled light from either an electronic sensor linked to an optical transmitter or a non-fiber optical sensor. The advantage of extrinsic sensors is that they extend to places that cannot be otherwise accessible—for example, measuring the inside of aircraft engines using fibers to pass radiation to a radiation pyrometer that is situated on the exterior part of the machines. Similarly, extrinsic fiber optic sensors can be utilized in measuring the internal temperature of electrical transformers, in which the presence of a high electromagnetic field makes it impossible to measure using other measurement techniques. Extrinsic fiber optic sensors offer an outstanding shield of the frequency signal from being corrupted by noise. Regrettably, several traditional sensors release electrical outputs that must be changed to optical signals for fiber use.