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Sample records for optical storage puzzle

  1. Puzzle-Based Storage Systems

    DTIC Science & Technology

    2007-02-06

    of r1formttion .1 .•0lltIr•t4 to avorae 1 maour per ro• porno td’n• thc tmo or r fl’E.rotlemo, ooor~n ui~t~ng f ’b 901 orinl .rn• ir ir’n-~nn th, domo...puzzle- based systems with aisle-based systems having different lane depths. We offer conclusions in Section 6. 2 Related literature Until late 2006...group cannot be reached from a sequence in the other. Sequences (1, 2, ... , 13, 14, 15) and (1, 2, ... , 13, 15, 14) are in different groups, for

  2. Manchester's Magiscope: An Interesting Optics Puzzle

    NASA Astrophysics Data System (ADS)

    Lancor, Rachael; Lancor, Brian

    2017-02-01

    The Magiscope was an attraction at Manchester's department store in Madison, WI, in 1939 that allowed children to peek into Santa's workshop (as shown in Fig. 1). The "magiscope" was a telescope-like device that gave children the illusion they were looking at a distant Santa, when in fact they were looking at a fabricated workshop on an upper level of the department store. In this article, we describe how we used the puzzle of the magiscope as a final assessment for our optics unit in an introductory physics course.

  3. Wideband optical storage

    NASA Technical Reports Server (NTRS)

    Heard, H. G.

    1979-01-01

    This paper has five purposes. First, to focus upon the key relationships that bound the technology choices for large, archival, digital storage devices; second, to identify the motivations for selecting the optical technology for a petabit-exabit level storage system (10 to the 15th to 10 to the 18th bits); third, to present a generic example and a specific implementation of a terabit-level optical storage device; fourth, to characterize the global design space constraints that will allow one to build a technology-limited optical store; and fifth, to sketch the outline of the BYTERON concept, a wideband 10 to the 16th to 10 to the 17th bit optical store concept and contrast its performance to that of an optical store that is in operation today

  4. Holographic Optical Data Storage

    NASA Technical Reports Server (NTRS)

    Timucin, Dogan A.; Downie, John D.; Norvig, Peter (Technical Monitor)

    2000-01-01

    Although the basic idea may be traced back to the earlier X-ray diffraction studies of Sir W. L. Bragg, the holographic method as we know it was invented by D. Gabor in 1948 as a two-step lensless imaging technique to enhance the resolution of electron microscopy, for which he received the 1971 Nobel Prize in physics. The distinctive feature of holography is the recording of the object phase variations that carry the depth information, which is lost in conventional photography where only the intensity (= squared amplitude) distribution of an object is captured. Since all photosensitive media necessarily respond to the intensity incident upon them, an ingenious way had to be found to convert object phase into intensity variations, and Gabor achieved this by introducing a coherent reference wave along with the object wave during exposure. Gabor's in-line recording scheme, however, required the object in question to be largely transmissive, and could provide only marginal image quality due to unwanted terms simultaneously reconstructed along with the desired wavefront. Further handicapped by the lack of a strong coherent light source, optical holography thus seemed fated to remain just another scientific curiosity, until the field was revolutionized in the early 1960s by some major breakthroughs: the proposition and demonstration of the laser principle, the introduction of off-axis holography, and the invention of volume holography. Consequently, the remainder of that decade saw an exponential growth in research on theory, practice, and applications of holography. Today, holography not only boasts a wide variety of scientific and technical applications (e.g., holographic interferometry for strain, vibration, and flow analysis, microscopy and high-resolution imagery, imaging through distorting media, optical interconnects, holographic optical elements, optical neural networks, three-dimensional displays, data storage, etc.), but has become a prominent am advertising

  5. Nanomaterials for optical data storage

    NASA Astrophysics Data System (ADS)

    Gu, Min; Zhang, Qiming; Lamon, Simone

    2016-12-01

    The growing amount of data that is generated every year creates an urgent need for new and improved data storage methods. Nanomaterials, which have unique mechanical, electronic and optical properties owing to the strong confinement of electrons, photons and phonons at the nanoscale, are enabling the development of disruptive methods for optical data storage with ultra-high capacity, ultra-long lifetime and ultra-low energy consumption. In this Review, we survey recent advancements in nanomaterials technology towards the next generation of optical data storage systems, focusing on metallic nanoparticles, graphene and graphene oxide, semiconductor quantum dots and rare-earth-doped nanocrystals. We conclude by discussing the use of nanomaterials in data storage systems that do not rely on optical mechanisms and by surveying the future prospects for the field.

  6. ICI optical data storage tape

    NASA Technical Reports Server (NTRS)

    Mclean, Robert A.; Duffy, Joseph F.

    1991-01-01

    Optical data storage tape is now a commercial reality. The world's first successful development of a digital optical tape system is complete. This is based on the Creo 1003 optical tape recorder with ICI 1012 write-once optical tape media. Several other optical tape drive development programs are underway, including one using the IBM 3480 style cartridge at LaserTape Systems. In order to understand the significance and potential of this step change in recording technology, it is useful to review the historical progress of optical storage. This has been slow to encroach on magnetic storage, and has not made any serious dent on the world's mountains of paper and microfilm. Some of the reasons for this are the long time needed for applications developers, systems integrators, and end users to take advantage of the potential storage capacity; access time and data transfer rate have traditionally been too slow for high-performance applications; and optical disk media has been expensive compared with magnetic tape. ICI's strategy in response to these concerns was to concentrate its efforts on flexible optical media; in particular optical tape. The manufacturing achievements, media characteristics, and media lifetime of optical media are discussed.

  7. Optical Storage Performance Modeling and Evaluation.

    ERIC Educational Resources Information Center

    Behera, Bailochan; Singh, Harpreet

    1990-01-01

    Evaluates different types of storage media for long-term archival storage of large amounts of data. Existing storage media are reviewed, including optical disks, optical tape, magnetic storage, and microfilm; three models are proposed based on document storage requirements; performance analysis is considered; and cost effectiveness is discussed.…

  8. Optical storage device

    NASA Technical Reports Server (NTRS)

    Welch, Sharon S.

    1991-01-01

    A new holographic image storage device which uses four-wave mixing in two photorefractive crystals is described. Photorefractive crystals promise information storage densities on the order of 10(exp 9) to 10(exp 12) bits per cubic centimeter at real-time rates. Several studies in recent years have investigated the use of photorefractive crystals for storing holographic image information. However, all of the previous studies have focused on techniques for storing information in a single crystal. The disadvantage of using a single crystal is that the read process is destructive. Researchers have developed techniques for fixing the information in a crystal so that it may be read many times. However, when fixed, the information cannot be readily erased and overwritten with new information. It two photorefractive crystals are used, holographic image information may be stored dynamically. That is, the stored image information may be read out more than once, and it may be easily erased and overwritten with new image information.

  9. Optical Storage Technology Subgroup (FIMUG)

    DTIC Science & Technology

    1990-04-01

    PROCUREMENT INSTRUMENT IDEyTiFiCAT,ON NUMBER ORGANIZATION (If applicable) US Army Corps of Engineers I 8c. ADDRESS (Citv. State, and ZIP Code) I0 SOURCE OF... Engineering , and Automation) are considered in relation to the current level of optical technology, and options for the US Army Corps of Engi- neers are... Engineer - ing, and Automation are provided in the report. Conclusions General conclusions are as follow: a. The use of optical storage technologies can

  10. Advanced optical disk storage technology

    NASA Technical Reports Server (NTRS)

    Haritatos, Fred N.

    1996-01-01

    There is a growing need within the Air Force for more and better data storage solutions. Rome Laboratory, the Air Force's Center of Excellence for C3I technology, has sponsored the development of a number of operational prototypes to deal with this growing problem. This paper will briefly summarize the various prototype developments with examples of full mil-spec and best commercial practice. These prototypes have successfully operated under severe space, airborne and tactical field environments. From a technical perspective these prototypes have included rewritable optical media ranging from a 5.25-inch diameter format up to the 14-inch diameter disk format. Implementations include an airborne sensor recorder, a deployable optical jukebox and a parallel array of optical disk drives. They include stand-alone peripheral devices to centralized, hierarchical storage management systems for distributed data processing applications.

  11. Optical Storage Developments--Write-Once Media.

    ERIC Educational Resources Information Center

    Edwards, Ian C.

    1987-01-01

    Discusses the user benefits of write-once optical storage devices; describes typical applications in archival storage, one-off complex instruction sets, and information storage and retrieval systems; and identifies current trends toward standardization of equipment. (CLB)

  12. Optical storage in lithium niobate

    NASA Technical Reports Server (NTRS)

    Alphonse, G. A.

    1976-01-01

    Holographic storage and retrieval using photorefractive media (electro-optic ferroelectric materials), particularly iron-doped lithium niobate with its enhanced sensitivity, are discussed. Refractive index changes induced by exposure to light render the materials useful for read-write memories and read-write memory simulation. Resolution, dark storage time, write and erase times, reversibility, and noise levels of the materials are examined. The laser source, deflection system, hololens, page composer, and detector array of the holographic memory system are described. High SNR and two orders of magnitude improvement in speed are reported over earlier experimental prototypes, but the system is still too slow to meet practical needs.

  13. Optical storage in quantized media

    NASA Astrophysics Data System (ADS)

    Djotyan, G. P.; Sandor, N.; Bakos, J. S.; Sörlei, Zs.

    2011-07-01

    The schemes of storing of images in quantum states of atoms being used nowadays are based on electromagnetically induced transparency. The images are stored in the collective atomic coherence with the storage time limited by different relaxation processes in the system with the transverse relaxation being the most detrimental among them. In this communication, we present a method of coherent writing of optical information (a transverse image) into the populations instead of the coherences of the metastable atomic states. The method is based on an action of a sequence of frequency chirped laser pulses on an atom with lambda-structure of working levels. Such storage results in drastic increase of the storage time. The reading out of the stored information is performed by measuring the population of one of the metastable atomic states.

  14. Multiwavelength optical storage of diarylethene PMMA films

    NASA Astrophysics Data System (ADS)

    Guo, Haobo; Zhang, Fushi; Sun, Fan; Pu, Shouzhi; Zhou, Xinhong

    2003-04-01

    Current applied optical storage technologies are all based on the heat effect of the recording laser, i.e., heat-mode optical storage. In the present work, photon-mode optical storage using photochromic diarylethene materials was investigated. Two diarylethene molecules dispersed into PMMA together was used as storage material. The recording layer was spin-coated on a glass substrate with Al reflective layer. Two laser beams of 532 nm and 650 nm were used in recording and readout by simultaneously writing and reading, and the reading lasers detected signals with high S/N ratio. Multi-wavelength storage was realized with the diarylethene PMMA film.

  15. ICI optical data storage tape: An archival mass storage media

    NASA Technical Reports Server (NTRS)

    Ruddick, Andrew J.

    1993-01-01

    At the 1991 Conference on Mass Storage Systems and Technologies, ICI Imagedata presented a paper which introduced ICI Optical Data Storage Tape. This paper placed specific emphasis on the media characteristics and initial data was presented which illustrated the archival stability of the media. More exhaustive analysis that was carried out on the chemical stability of the media is covered. Equally important, it also addresses archive management issues associated with, for example, the benefits of reduced rewind requirements to accommodate tape relaxation effects that result from careful tribology control in ICI Optical Tape media. ICI Optical Tape media was designed to meet the most demanding requirements of archival mass storage. It is envisaged that the volumetric data capacity, long term stability and low maintenance characteristics demonstrated will have major benefits in increasing reliability and reducing the costs associated with archival storage of large data volumes.

  16. Puzzling Mechanisms

    ERIC Educational Resources Information Center

    van Deventer, M. Oskar

    2009-01-01

    The basis of a good mechanical puzzle is often a puzzling mechanism. This article will introduce some new puzzling mechanisms, like two knots that engage like gears, a chain whose links can be interchanged, and flat gears that do not come apart. It illustrates how puzzling mechanisms can be transformed into real mechanical puzzles, e.g., by…

  17. Puzzling Mechanisms

    ERIC Educational Resources Information Center

    van Deventer, M. Oskar

    2009-01-01

    The basis of a good mechanical puzzle is often a puzzling mechanism. This article will introduce some new puzzling mechanisms, like two knots that engage like gears, a chain whose links can be interchanged, and flat gears that do not come apart. It illustrates how puzzling mechanisms can be transformed into real mechanical puzzles, e.g., by…

  18. The Open Approach to Optical Storage.

    ERIC Educational Resources Information Center

    Noordenbos, Meino G.

    1987-01-01

    Discusses the need for user oriented optical storage systems to deal with information storage in offices, and describes the Megadoc system. The features described include hardware configurations, microcomputer applications, the ability to read microfilm or microfiche documents, equipment standards, and current systems software. (CLB)

  19. Optical data storage and metallization of polymers

    NASA Technical Reports Server (NTRS)

    Roland, C. M.; Sonnenschein, M. F.

    1991-01-01

    The utilization of polymers as media for optical data storage offers many potential benefits and consequently has been widely explored. New developments in thermal imaging are described, wherein high resolution lithography is accomplished without thermal smearing. The emphasis was on the use of poly(ethylene terephthalate) film, which simultaneously serves as both the substrate and the data storage medium. Both physical and chemical changes can be induced by the application of heat and, thereby, serve as a mechanism for high resolution optical data storage in polymers. The extension of the technique to obtain high resolution selective metallization of poly(ethylene terephthalate) is also described.

  20. Superresolution applied to optical data storage systems

    NASA Astrophysics Data System (ADS)

    Walker, Edwin Parker

    1999-09-01

    This dissertation investigates superresolution applications in optical data storage systems. The performance of standard and superresolving magneto-optic data storage system are quantified by scalar diffraction modeling and experiments. Classical resolution measures are reviewed. Background on superresolution definitions and their conceptual development in scanning optical microscopes, optical data storage, and image processing is presented. Figures of merit for quantifying the performance of the systems are reviewed, such as system transfer function, two-point response, focused spot size, and signal-to-noise ratio. The description of the scalar diffraction modeling used to simulate an optical data storage system is reviewed. Operation of the magneto-optic data storage system and tradeoffs of superresolving techniques are discussed. The signal and noise spatial distribution in the pupil of an optical data storage system are shown to be different. For a particular spatial frequency bandwidth, the signal and noise are concentrated in different regions of the pupil. This understanding allows the use of optical filters that partially equalize the system transfer function and increase the signal-to-noise ratio. The main superresolution techniques investigated are those that increase the transmission of the higher spatial frequencies, or equalize the system transfer function, without changing the system cutoff frequency. The optical methods used to achieve superresolution are amplitude and phase filters placed in strategic system locations. One location influences the properties of the focused spot such as the irradiance distribution and width of the central core. Another location does not change the focused spot at all, but does change the signal and noise properties of the system. Electronic filtering techniques are also used to increase the transmission of the high spatial frequencies. The amplitude and phase filter sensitivities to aberration are also investigated

  1. Optical Storage and Retrieval of Library Material.

    ERIC Educational Resources Information Center

    Folen, Doris R.; Stackpole, Laurie E.

    1993-01-01

    Describes the newly installed optical disk storage system at the Naval Research Laboratory's Research Library and Technical Information Center. Planning and design of the system, the conversion of 140,000 reports to optical disk, the information retrieval process, and future plans are covered. (Contains nine references.) (KRN)

  2. Liquid crystals for holographic optical data storage.

    PubMed

    Matharu, Avtar S; Jeeva, Shehzad; Ramanujam, P S

    2007-12-01

    A tutorial review is presented to inform and inspire the reader to develop and integrate strong scientific links between liquid crystals and holographic data storage, from a materials scientist's viewpoint. The principle of holographic data storage as a means of providing a solution to the information storage demands of the 21st century is detailed. Holography is a small subset of the much larger field of optical data storage and similarly, the diversity of materials used for optical data storage is enormous. The theory of polarisation holography which produces holograms of constant intensity, is discussed. Polymeric liquid crystals play an important role in the development of materials for holographic storage and photoresponsive materials based on azobenzene are targeted for discussion due to their ease of photo-reversion between trans- and cis-states. Although the final polymer may not be liquid crystalline, irradiation can induce ordered domains. The mesogens act in a co-operative manner, enhancing refractive indices and birefringences. Surface relief gratings are discussed as a consequence of holographic storage. Cholesteric polymers comprising azobenzene are briefly highlighted. Irradiation causing cis-trans-isomerisation can be used to control helix pitch. A brief mention of liquid crystals is also made since these materials may be of future interest since they are optically transparent and amenable to photo-induced anisotropy.

  3. Holographic Optical Storage Using Photorefractive Polymers

    NASA Technical Reports Server (NTRS)

    Hayden, L. Michael; Strutz, Shane J.; Harris, Kristi; Ayachitula, Rajani

    2000-01-01

    The task for this report is to perform the basic research and develop a prototype benchtop holographic optical storage system based on photochromic and/or photorefractive polymers so that both permanent and erasable images may be stored and retrieved in the same mixed polymer medium. The task consist of: assembly and setup of the benchtop holographic storage system, including lasers, optics, and other ancillary equipment in a laboratory setting; and research and development of a suitable polymer matrix that will allow practical storage and retrieval of digital data. This will necessitate molecular design of the matrices involved and subsequent physics test to verify the characteristics of the matrices provide practical storage and retrieval.

  4. Optical Data Storage Capabilities of Bacteriorhodopsin

    NASA Technical Reports Server (NTRS)

    Gary, Charles

    1998-01-01

    We present several measurements of the data storage capability of bacteriorhodopsin films to help establish the baseline performance of this material as a medium for holographic data storage. In particular, we examine the decrease in diffraction efficiency with the density of holograms stored at one location in the film, and we also analyze the recording schedule needed to produce a set of equal intensity holograms at a single location in the film. Using this information along with the assumptions about the performance of the optical system, we can estimate potential data storage densities in bacteriorhodopsin.

  5. Biomolecular optical data storage and data encryption.

    PubMed

    Fischer, Thorsten; Neebe, Martin; Juchem, Thorsten; Hampp, Norbert A

    2003-03-01

    The use of bacteriorhodopsin (BR) as an active layer in write-once-read-many optical storage is presented. This novel feature of BR materials may be used on a wide variety of substrates, among them transparent substrates but also paper and plastics. The physical basis of the recording process is polarization-sensitive two-photon absorption. As an example for this new BR application, an identification card equipped with an optical recording strip is presented, which has a capacity of about 1 MB of data. The recording density currently used is 125 kB/cm2, which is far from the optical limits but allows operation with cheap terminals using plastic optics. In the examples given, data are stored in blocks of 10 kB each. A special optical encryption procedure allows the stored data to be protected from unauthorized reading. The molecular basis of this property is again the polarization-sensitive recording mechanism. The unique combination of optical storage, photochromism, and traceability of the BR material is combined on the single-molecule level. BR introduces a new quality of storage capability for applications with increased security and anticounterfeiting requirements.

  6. Optical storage media data integrity studies

    NASA Technical Reports Server (NTRS)

    Podio, Fernando L.

    1994-01-01

    Optical disk-based information systems are being used in private industry and many Federal Government agencies for on-line and long-term storage of large quantities of data. The storage devices that are part of these systems are designed with powerful, but not unlimited, media error correction capacities. The integrity of data stored on optical disks does not only depend on the life expectancy specifications for the medium. Different factors, including handling and storage conditions, may result in an increase of medium errors in size and frequency. Monitoring the potential data degradation is crucial, especially for long term applications. Efforts are being made by the Association for Information and Image Management Technical Committee C21, Storage Devices and Applications, to specify methods for monitoring and reporting to the user medium errors detected by the storage device while writing, reading or verifying the data stored in that medium. The Computer Systems Laboratory (CSL) of the National Institute of Standard and Technology (NIST) has a leadership role in the development of these standard techniques. In addition, CSL is researching other data integrity issues, including the investigation of error-resilient compression algorithms. NIST has conducted care and handling experiments on optical disk media with the objective of identifying possible causes of degradation. NIST work in data integrity and related standards activities is described.

  7. Optical storage media data integrity studies

    NASA Astrophysics Data System (ADS)

    Podio, Fernando L.

    1994-03-01

    Optical disk-based information systems are being used in private industry and many Federal Government agencies for on-line and long-term storage of large quantities of data. The storage devices that are part of these systems are designed with powerful, but not unlimited, media error correction capacities. The integrity of data stored on optical disks does not only depend on the life expectancy specifications for the medium. Different factors, including handling and storage conditions, may result in an increase of medium errors in size and frequency. Monitoring the potential data degradation is crucial, especially for long term applications. Efforts are being made by the Association for Information and Image Management Technical Committee C21, Storage Devices and Applications, to specify methods for monitoring and reporting to the user medium errors detected by the storage device while writing, reading or verifying the data stored in that medium. The Computer Systems Laboratory (CSL) of the National Institute of Standard and Technology (NIST) has a leadership role in the development of these standard techniques. In addition, CSL is researching other data integrity issues, including the investigation of error-resilient compression algorithms. NIST has conducted care and handling experiments on optical disk media with the objective of identifying possible causes of degradation. NIST work in data integrity and related standards activities is described.

  8. Optical Imaging versus Paper Records Storage.

    ERIC Educational Resources Information Center

    Baldygo, Robert

    1999-01-01

    States that the maintenance and storage of paper documents has many inherent weaknesses, including hidden costs and attached risks. Asserts that document imaging is a viable, up-to-date technology that could eliminate many of these costs and risks. Describes the system benefits, scope, requirements, and costs and the legality of optically stored…

  9. Optical information storage in cellular mobile terminals

    NASA Astrophysics Data System (ADS)

    Makela, Jakke S.; Aikio, Janne K.; Vadde, Venkatesh; Kolehmainen, Timo T.; Karioja, Pentti

    2001-11-01

    The trend towards so-called digital convergence (multiple functionality within a single terminal) is opening up a need for high-capacity storage within the cellular mobile terminals (CMT). Solid-state memories and magnetic microdrives are the most commercially mature options. Optical disk technology in this size range is immature, but has a unique potential: no other medium at present has the capability to be simultaneously low-cost, high-capacity, and exchangeable. In this paper, we explore the requirements for the implementation of optical disk storage in a CMT environment. From the technical point of view, these requirements include small form factor, high-enough data density and throughput, low power consumption, robustness, low cost, mass productability, and modularity. Although current technologies may satisfy some of these requirements individually, there is a need for combined optimization of all of these parameters. From the commercial point of view, the most crucial requirement is global standardization. Such standardization is crucial if wide interoperability is wanted (between CMT manufacturers, and even more crucially between CMTs and other appliances). Current optical storage standards are industry-driven and tend to be proprietary and/or incompatible. Even if the technical challenges can be met, optical data storage is not likely to be accepted in CMT applications unless global standardization proceeds more quickly than it is doing at present.

  10. Photonic nanojet-enabled optical data storage.

    PubMed

    Kong, Soon-Cheol; Sahakian, Alan; Taflove, Allen; Backman, Vadim

    2008-09-01

    We show that our recently reported microwave photonic jet technique for detection of deeply subwavelength pits in a metal substrate can be extended to optical wavelengths for purposes of high-density data storage. Three-dimensional finite-difference time-domain computational solutions of Maxwell's equations are used to optimize the photonic nanojet and pit configuration to account for the Drude dispersion of an aluminum substrate in the spectral range near lambda= 400 nm. Our results show that nanojet-illuminated pits having lateral dimensions of only 50 nm x 80 nm yield a contrast ratio 27 dB greater than previously reported using a lens system for pits of similar area. Such pits are much smaller than BluRay features. The high detection contrast afforded by the photonic nanojet could potentially yield significant increases in data density and throughput relative to current commercial optical data-storage systems while retaining the basic geometry of the storage medium.

  11. Challenges and opportunities for optical storage

    NASA Astrophysics Data System (ADS)

    Chen, Di

    2005-09-01

    Optical technique for data storage was driven from the challenges to achieve data storage performance required by the user. The first attempt to address the recording density improvement over HDD using magneto-optic technology started over thirty years ago. Subsequent efforts to develop 15", 12" and 5 and 1/4" WORM disc drives met with limited success. Advances in semiconductor lasers, lithography, and auto focusing and tracking techniques finally allow the development of the Compact Disc to answer the call for improvement in audio recording technology and data distribution in mid to late 1980. Recordable and erasable technology then followed with the introduction of CD-R, CD-RW and MO drives and media. By early 1990, advances in high density recording with the use of shorter wavelength lasers, larger n.a. lenses, improved lithographic and data compression techniques, allows the development of 4.7 GB DVD drives and discs to answer the challenge for recording 2-hour high quality movies on a CD size disc. Recordable and erasable DVD became available in 2000, and Dual Layer DVD was introduced last year . With the advent of HDTV and movie in recent years, Storage of 25 GB data in a DVD disc is needed. Blue-ray and HD-DVD are the leading technologies to answer this challenge. Looking to the future, optical storage areal density of one to two orders of magnitude improvement will be required to compete with HDD which is now reaching 133 Gb/in2 . In addition, high data transfer rate of 1Gb/s, data security, copy protection, ease of use, cost and standards issues sums up the monumental challenges facing the optical recording industry in the years to come. Some of the leading technologies, such as multi-layer, new encoding schemes, volume recording, near-field optics, micro-optics, domain expansion, UV laser, holographic storage, could provide the answers. Meeting these challenges, optical storage could become the dominant recording technology to satisfy the data storage

  12. Optical storage characters of bacteriorhodopsin molecule film

    NASA Astrophysics Data System (ADS)

    Chen, Feng; Yang, Qing; Wu, Hongcai; Hou, Xun

    2002-04-01

    The photochromic retinal protein bacteriorhodopsin (BR) is found in the cell membrane of Halobacterium salinarium. It is the key protein for photosynthetic growth of H.salinarium. BR shows an exceptional stability towards chemical, thermal, and photochemical degradation. The photochromic properties of Bacteriorhodopsin provide the possibility of application in optical information storage. Photoexcition of the O-state of BR, which has an all-trans confirmation, leads to a state with 9-cis configuration, which is thermally stable. The 9-cis containing photoproduct of the O-state was named P-state. It absorbs at 490 nm and can be photochemically reconverted to the initial state. We propose a system of optical information storage in a BR polymer film, which is a reversible optical data recording material and can be rewritten over 106 times without degradation of the film. A three-wavelength EDRAW (Erase Direct Read After Write) experiment was performed. The photoexcited P(490) state shows a permanent storage property confirmed by our contrast ratio experiments. The result of long-term information storage in BR films more than 1 year is obtained.

  13. Optical Pickup Feeding Velocity Profile Design of Optical Disk Storage

    NASA Astrophysics Data System (ADS)

    Park, Juhn Ho; Seo, Heui-Sik; Lee, Jung Joon; Min, Byunghoon; Son, Heuigi

    2001-03-01

    Residual vibrations and jerks of a pickup body caused by the flexibility of an optical pickup feeding system in optical disk storage may degrade the quality of reading and writing, and increase the track access time. In this study, a feeding velocity profile that suppresses the residual vibrations and jerks is calculated and applied to a stepping-motor-driven feeding system. The calculated feeding velocity profile shows good results compared to the conventional feeding velocity profile of trapezoidal shape.

  14. Encrypted optical storage with angular multiplexing.

    PubMed

    Matoba, O; Javidi, B

    1999-12-11

    We present the first, to our knowledge, demonstration of an encrypted optical storage based on double-random phase encoding by using angular multiplexing in a photorefractive material. Original two-dimensional data are encrypted by use of two random phase codes located in the input and the Fourier planes and are then stored holographically in a LiNbO(3):Fe crystal. The retrieval of the original data can be achieved with a phase-conjugated readout scheme. We demonstrate the encryption and the decryption of multiple frames of two-dimensional digital data by using angular multiplexing. We also evaluate numerically the influence of the bandwidth of the optical system on the decrypted digital data. The bit error rate as a function of the optical system bandwidth is presented.

  15. Puzzles & Problems.

    ERIC Educational Resources Information Center

    Murphy, Pat, Ed.

    1993-01-01

    "Exploring" is a magazine of science, art, and human perception, produced by Exploratorium in collaboration with other participating museums. This issue focuses on puzzles and problem solving. Brain teasers, puzzles, and the strategies for solving them are included. Features include: (1) "Homework Assignment #3" (Paul Doherty);…

  16. Fiendishly puzzling

    NASA Astrophysics Data System (ADS)

    2016-12-01

    The UK's Government Communications Headquarters (GCHQ) has, over the last few years, published puzzles that keen members of the public could solve to get noticed by the organization's recruitment team. The GCHQ Puzzle Book is a chunky compendium whose readers are introduced to the whole back catalogue.

  17. Balloon borne optical disk mass storage system

    NASA Technical Reports Server (NTRS)

    Vanek, M. D.; Jennings, D. A.

    1991-01-01

    An on-board data recording system for balloon-borne interferometer using a vacuum operable, ruggedized WORM optical drive is presented. This system, as presently under development, provides 320 Mbytes of data storage (or approximately 11 hrs at the 64 kbits/sec telemetry rate of the experiment). It has the capability of recording the unmodified telemetry bit system as transmitted or doing some preprocessing of the data onboard. The system is compact and requires less than 28 watts of battery power to operate.

  18. Optical information storage of bacteriorhodopsin molecule film

    NASA Astrophysics Data System (ADS)

    Chen, Feng; Li, Baofang; Hou, Xun; Li, XingChang; Jiang, Long; Sanio, Markus; Hampp, Norbert A.

    2000-11-01

    The photochromic retinal protein bacteriorhodopsin (BR) is found in the cell membrane of Halobacterium salinarium. It is the key protein for photosynthetic growth of H.salinarium. BR shows an exceptional stability towards chemical, thermal, and photochemical degradation. In this paper, we propose a system of optical information storage in a BR polymer film. A three- wavelength EDRAW (Erase Direct Read After Write) experiment was performed. The photoexcited P(490) state shows a permanent storage property confirmed by our contrast ratio experiments. We have performed the reversible operations of 'write' and 'erase' with the BR polymer film over hundreds of cycles in our experiments. The readout contrast ratio is very sensitive to the intensity and wavelength of probe beam and the recorded data can be readout from 530 to approximately 630 nm with different contrast ratio. Within the range of 570 to approximately 600 nmm, the better contrast ratio can be obtained. Considering the erasing effect for the reason of absorption of P state, both higher contrast ratio and nondestructive reading can be realized by using 594 nm as the readout wavelength. The experimental result such BR material is very suitable for long-term photochromic information storage.

  19. Multi-wavelength optical storage of diarylethene PMMA film

    NASA Astrophysics Data System (ADS)

    Guo, Haobo; Zhang, Fushi; Wu, Guo-shi; Sun, Fan; Pu, Shouzhi; Mai, Xuesong; Qi, Guosheng

    2003-05-01

    Current commercial optical storage technologies are all based on the heat effect of the recording laser, i.e., heat-mode optical storage. In the present work, photon-mode optical storage using photochromic diarylethene materials was investigated. Two diarylethene derivatives were dispersed into PMMA solution, and spin-coated on a glass substrate with Al reflective layer as the recording layer. Two laser beams of 532 and 650 nm were used in recording and readout simultaneously, and signals with high S/ N ratio were detected. Multi-wavelength optical storage was realized with the diarylethene PMMA film.

  20. Special Reports: Optical Disks: Mass Storage of Information.

    ERIC Educational Resources Information Center

    McLeod, Jonah

    1984-01-01

    Examines trends in the mass storage of information using optical disks, focusing on applications and various types of systems. Includes a list of optical disk drive products with manufacturer, product, capacity, and access time. (JN)

  1. Lockean Puzzles

    ERIC Educational Resources Information Center

    Milligan, Tony

    2007-01-01

    In analytic moral philosophy it is standard to use unrealistic puzzles to set up moral dilemmas of a sort that I will call Lockean Puzzles. This paper will try to pinpoint just what is and what is not problematic about their use as a teaching tool or component part of philosophical arguments. I will try to flesh out the claim that what may be lost…

  2. Pilot Project for Spaceborne Massive Optical Storage Devices

    NASA Technical Reports Server (NTRS)

    Chen, Y. J.

    1996-01-01

    A space bound storage device has many special requirements. In addition to large storage capacity, fas read/ write time, and high reliability, it also needs to have small volume, light weight, low power consumption, radiation hardening, ability to operate in extreme temperature ranges, etc. Holographic optical recording technology, which has been making major advancements in recent years, is an extremely promising candidate. The goal of this pilot project is to demonstrate a laboratory bench-top holographic optical recording storage system (HORSS) based on nonlinear polymer films 1 and/or other advanced photo-refractive materials. This system will be used as a research vehicle to study relevant optical properties of novel holographic optical materials, to explore massive optical storage technologies based on the photo-refractive effect and to evaluate the feasibility of developing a massive storage system, based on holographic optical recording technology, for a space bound experiment in the near future.

  3. Pilot Project for Spaceborne Massive Optical Storage Devices

    NASA Technical Reports Server (NTRS)

    Chen, Y. J.

    1996-01-01

    A space bound storage device has many special requirements. In addition to large storage capacity, fas read/ write time, and high reliability, it also needs to have small volume, light weight, low power consumption, radiation hardening, ability to operate in extreme temperature ranges, etc. Holographic optical recording technology, which has been making major advancements in recent years, is an extremely promising candidate. The goal of this pilot project is to demonstrate a laboratory bench-top holographic optical recording storage system (HORSS) based on nonlinear polymer films 1 and/or other advanced photo-refractive materials. This system will be used as a research vehicle to study relevant optical properties of novel holographic optical materials, to explore massive optical storage technologies based on the photo-refractive effect and to evaluate the feasibility of developing a massive storage system, based on holographic optical recording technology, for a space bound experiment in the near future.

  4. Multi-wavelength multi-level optical storage

    NASA Astrophysics Data System (ADS)

    Wullert, John R., II

    Current digital information storage technologies offer rapid access and seemingly ever-increasing capacities. New storage techniques that improve the data rate of high-density storage technologies are attractive, particularly for cost-sensitive services such as video on demand. Wavelength multiplexing of optical information storage has the potential to increase storage capacity, density and data rate. This dissertation addresses the design, simulation and fabrication of a multi-wavelength, multi-level optical storage structure that has the potential to increase the capacity, density and data rate of optical storage. Multi-wavelength, multi-layer optical storage is a technique for storing data in many separate layers in a medium, where each layer responds to a unique optical wavelength. This approach builds on the strengths of current optical storage technologies and addresses some of their limitations. Multiple layers of storage increase the high storage density possible with optical techniques and the parallelism of wavelength multiplexing improves the relatively low data rate. Multi-wavelength, multi-level optical storage has been investigated theoretically and experimentally. The experimental results provide the first demonstration of optical storage using three wavelengths to read three separate layers of information. These read-only optical memories were based on dielectric mirrors of silicon dioxide, magnesium oxide and aluminum oxide. The layers were designed to be read with semiconductor lasers of 635, 780 and 980 nanometers. The prototype devices exhibited open margins between the on and off states for all eight combinations of the presence and absence of the three mirrors. Theoretical simulations were employed to assess the dynamic operation of multi-wavelength storage devices. Through systematic simulations, variations in the thickness and refractive index of the layers in the structure were identified as the primary noise mechanism and a critical

  5. Optical system storage design with diffractive optical elements

    NASA Technical Reports Server (NTRS)

    Kostuk, Raymond K.; Haggans, Charles W.

    1993-01-01

    Optical data storage systems are gaining widespread acceptance due to their high areal density and the ability to remove the high capacity hard disk from the system. In magneto-optical read-write systems, a small rotation of the polarization state in the return signal from the MO media is the signal which must be sensed. A typical arrangement used for detecting these signals and correcting for errors in tracking and focusing on the disk is illustrated. The components required to achieve these functions are listed. The assembly and alignment of this complex system has a direct impact on cost, and also affects the size, weight, and corresponding data access rates. As a result, integrating these optical components and improving packaging techniques is an active area of research and development. Most designs of binary optic elements have been concerned with optimizing grating efficiency. However, rigorous coupled wave models for vector field diffraction from grating surfaces can be extended to determine the phase and polarization state of the diffracted field, and the design of polarization components. A typical grating geometry and the phase and polarization angles associated with the incident and diffracted fields are shown. In our current stage of work, we are examining system configurations which cascade several polarization functions on a single substrate. In this design, the beam returning from the MO disk illuminates a cascaded grating element which first couples light into the substrate, then introduces a quarter wave retardation, then a polarization rotation, and finally separates s- and p-polarized fields through a polarization beam splitter. The input coupler and polarization beam splitter are formed in volume gratings, and the two intermediate elements are zero-order elements.

  6. X-ray versus Optical Variations in the Seyfert 1 Nucleus NGC 3516: A Puzzling Disconnectedness

    NASA Technical Reports Server (NTRS)

    Maoz, Dan; Markowitz, Alex; Edelson, Rick; Nandra, Kirpal; White, Nicholas E. (Technical Monitor)

    2002-01-01

    We present optical broadband (B and R) observations of the Seyfert 1 nucleus NGC 3516, obtained at Wise Observatory from March 1997 to March 2002, contemporaneously with X-ray 2-10 keV measurements with RXTE. With these data we increase the temporal baseline of this dataset to 5 years, more than triple to the coverage we have previously presented for this object. Analysis of the new data does not confirm the 100-day lag of X-ray behind optical variations, tentatively reported in our previous work. Indeed, excluding the first year's data, which drive the previous result, there is no significant correlation at any Lag between the X-ray and optical bands. We also find no correlation at any lag between optical flux and various X-ray hardness ratios. We conclude that the close relation observed between the bands during the first year of our program was either a fluke, or perhaps the result of the exceptionally bright state of NGC 3516 in 1997, to which it has yet to return. Reviewing the results of published joint X-ray and UV/optical Seyfert monitoring programs, we speculate that there are at least two components or mechanisms contributing to the X-ray continuum emission up to 10 key: a soft component that is correlated with UV/optical variations on timescales approx. greater than 1 day, and whose presence can be detected when the source is observed at low enough energies (approx. 1 keV), is unabsorbed, or is in a sufficiently bright phase; and a hard component whose variations are uncorrelated with the UV/optical.

  7. Research Studies on Advanced Optical Module/Head Designs for Optical Data Storage

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Preprints are presented from the recent 1992 Optical Data Storage meeting in San Jose. The papers are divided into the following topical areas: Magneto-optical media (Modeling/design and fabrication/characterization/testing); Optical heads (holographic optical elements); and Optical heads (integrated optics). Some representative titles are as follow: Diffraction analysis and evaluation of several focus and track error detection schemes for magneto-optical disk systems; Proposal for massively parallel data storage system; Transfer function characteristics of super resolving systems; Modeling and measurement of a micro-optic beam deflector; Oxidation processes in magneto-optic and related materials; and A modal analysis of lamellar diffraction gratings in conical mountings.

  8. Puzzle Pieces

    NASA Image and Video Library

    2012-05-02

    Platy lava flows in Elysium look very different from the thicker flows of the Tharsis region. In this image from NASA 2001 Mars Odyssey spacecraft, the darker plates are separated by lighter material and some edges match-up like puzzle pieces.

  9. Deductive Puzzling

    ERIC Educational Resources Information Center

    Wanko, Jeffrey J.

    2010-01-01

    To help fifth- through eighth-grade students develop their deductive reasoning skills, the author used a ten-week supplementary curriculum so that students could answer logic questions. The curriculum, a series of lessons built around language-independent logic puzzles, has been used in classrooms of fifth through eighth grades. In most cases,…

  10. Experimental study of optical storage characteristics of photochromic material: pyrrylfulgide

    NASA Astrophysics Data System (ADS)

    Lei, Ming; Yao, Baoli; Chen, Yi; Han, Yong; Wang, Congmin; Wang, Yingli; Menke, Neimule; Chen, Guofu; Fan, Meigong

    2003-04-01

    Optical data storage is a frontier in the information science. Currently, there are mainly two kinds of storage materials, i.e., thermal-optic and photonic materials. The storage methods are divided into serial and parallel modes. In the market, the mature technique is CD-RW, which uses the thermal-optic material and serial method. The storage density of the CD-RW is restricted by the size of material particles, the conduction of heat, etc. Besides, the recording speed is seriously limited by the process of heating. Photonic materials and parallel method will be the trend in the optical data storage. Because it is based on the photon reaction on the molecule scale, the storage density and speed will be greatly increased. In this paper, a new kind of organic photochromic material -- pyrrylfulgide was studied. A parallel optical data storage system was established. Using the pyrrylfulgide/PMMA film as a recording medium, micro-images and binary digital information could be recorded, readout and erased in this parallel system. The recorded information on the film can be kept for at least 8 months in dark at room temperature. So far, the storage density is 3 x 107 bit/cm2.

  11. Multiplexed Holographic Optical Data Storage In Thick Bacteriorhodopsin Films

    NASA Technical Reports Server (NTRS)

    Downie, John D.; Timucin, Dogan A.; Gary, Charles K.; Ozcan, Meric; Smithey, Daniel T.; Crew, Marshall

    1998-01-01

    The optical data storage capacity of photochromic bacteriorhodopsin films is investigated by means of theoretical calculations, numerical simulations, and experimental measurements on sequential recording of angularly multiplexed diffraction gratings inside a thick D85N BR film.

  12. Multiplexed Holographic Optical Data Storage In Thick Bacteriorhodopsin Films

    NASA Technical Reports Server (NTRS)

    Downie, John D.; Timucin, Dogan A.; Gary, Charles K.; Ozcan, Meric; Smithey, Daniel T.; Crew, Marshall

    1998-01-01

    The optical data storage capacity of photochromic bacteriorhodopsin films is investigated by means of theoretical calculations, numerical simulations, and experimental measurements on sequential recording of angularly multiplexed diffraction gratings inside a thick D85N BR film.

  13. Optical signatures of molecular dissymmetry: combining theory with experiments to address stereochemical puzzles.

    PubMed

    Mukhopadhyay, Parag; Wipf, Peter; Beratan, David N

    2009-06-16

    Modern chemistry emerged from the quest to describe the three-dimensional structure of molecules: van't Hoff's tetravalent carbon placed symmetry and dissymmetry at the heart of chemistry. In this Account, we explore how modern theory, synthesis, and spectroscopy can be used in concert to elucidate the symmetry and dissymmetry of molecules and their assemblies. Chiroptical spectroscopy, including optical rotatory dispersion (ORD), electronic circular dichroism (ECD), vibrational circular dichroism (VCD), and Raman optical activity (ROA), measures the response of dissymmetric structures to electromagnetic radiation. This response can in turn reveal the arrangement of atoms in space, but deciphering the molecular information encoded in chiroptical spectra requires an effective theoretical approach. Although important correlations between ECD and molecular stereochemistry have existed for some time, a battery of accurate new theoretical methods that link a much wider range of chiroptical spectroscopies to structure have emerged over the past decade. The promise of this field is considerable: theory and spectroscopy can assist in assigning the relative and absolute configurations of complex products, revealing the structure of noncovalent aggregates, defining metrics for molecular diversity based on polarization response, and designing chirally imprinted nanomaterials. The physical organic chemistry of chirality is fascinating in its own right: defining atomic and group contributions to optical rotation (OR) is now possible. Although the common expectation is that chiroptical response is determined solely by a chiral solute's electronic structure in a given environment, chiral imprinting effects on the surrounding medium and molecular assembly can, in fact, dominate the chiroptical signatures. The theoretical interpretation of chiroptical markers is challenging because the optical properties are subtle, resulting from the strong electric dipole and the weaker electric

  14. Optical signatures of molecular dissymmetry: Combining theory with experiments to address stereochemical puzzles

    PubMed Central

    Mukhopadhyay, Parag; Wipf, Peter; Beratan, David N.

    2009-01-01

    Conspectus Modern chemistry emerged from the quest to describe the three-dimensional structure of molecules: van’t Hoff’s tetravalent carbon placed symmetry and dissymmetry at the heart of chemistry. In this Account, we explore how modern theory, synthesis, and spectroscopy can be used in concert to elucidate the symmetry and dissymmetry of molecules and their assemblies. Chiroptical spectroscopy—including optical rotatory dispersion (ORD), electronic circular dichroism (ECD), vibrational circular dichroism (VCD), and Raman optical activity (ROA)—measures the response of dissymmetric structures to electromagnetic radiation. This response can in turn reveal the arrangement of atoms in space, but deciphering the molecular information encoded in chiroptical spectra requires an effective theoretical approach. Although important correlations between ECD and molecular stereochemistry have existed for some time, a battery of accurate new theoretical methods that link a much wider range of chiroptical spectroscopies to structure have emerged over the last decade. The promise of this field is considerable: theory and spectroscopy can assist in assigning the relative and absolute configurations of complex products, in revealing the structure of non-covalent aggregates, in defining metrics for molecular diversity based upon polarization response, and in designing chirally imprinted nanomaterials. The physical organic chemistry of chirality is fascinating in its own right: defining atomic and group contributions to optical rotation (OR) is now possible. Although the common expectation is that chiroptical response is determined solely by a chiral solute’s electronic structure in a given environment, chiral imprinting effects on the surrounding medium and molecular assembly can, in fact, dominate the chiroptical signatures. The theoretical interpretation of chiroptical markers is challenging because the optical properties are subtle, which results from the strong

  15. A new tape product for optical data storage

    NASA Technical Reports Server (NTRS)

    Larsen, T. L.; Woodard, F. E.; Pace, S. J.

    1993-01-01

    A new tape product has been developed for optical data storage. Laser data recording is based on hole or pit formation in a low melting metallic alloy system. The media structure, sputter deposition process, and media characteristics, including write sensitivity, error rates, wear resistance, and archival storage are discussed.

  16. A Chaucer Puzzle.

    ERIC Educational Resources Information Center

    Darrell, C. B.; Payne, Lynne

    1978-01-01

    Suggests the use of a hunt-a-word puzzle as a test of students' knowledge of Middle English words in the prologue of "The Canterbury Tales." Includes the puzzle questions, answers, puzzle grid, and answer grid. (TJ)

  17. Quasi-light storage for optical data packets.

    PubMed

    Schneider, Thomas; Preußler, Stefan

    2014-02-06

    Today's telecommunication is based on optical packets which transmit the information in optical fiber networks around the world. Currently, the processing of the signals is done in the electrical domain. Direct storage in the optical domain would avoid the transfer of the packets to the electrical and back to the optical domain in every network node and, therefore, increase the speed and possibly reduce the energy consumption of telecommunications. However, light consists of photons which propagate with the speed of light in vacuum. Thus, the storage of light is a big challenge. There exist some methods to slow down the speed of the light, or to store it in excitations of a medium. However, these methods cannot be used for the storage of optical data packets used in telecommunications networks. Here we show how the time-frequency-coherence, which holds for every signal and therefore for optical packets as well, can be exploited to build an optical memory. We will review the background and show in detail and through examples, how a frequency comb can be used for the copying of an optical packet which enters the memory. One of these time domain copies is then extracted from the memory by a time domain switch. We will show this method for intensity as well as for phase modulated signals.

  18. Optical Digital Disks as Mass Storage Media.

    ERIC Educational Resources Information Center

    Boss, Richard W.

    1983-01-01

    Describes the optical digital disk, which stores machine-readable information in digitized form, and discusses their production, cost, present and future applications. The major companies currently active in the disk field are noted. (MBR)

  19. Optical Digital Disks as Mass Storage Media.

    ERIC Educational Resources Information Center

    Boss, Richard W.

    1983-01-01

    Describes the optical digital disk, which stores machine-readable information in digitized form, and discusses their production, cost, present and future applications. The major companies currently active in the disk field are noted. (MBR)

  20. Plasmonic nano-structures for optical data storage.

    PubMed

    Mansuripur, M; Zakharian, A R; Lesuffleur, A; Oh, Sang-Hyun; Jones, R J; Lindquist, N C; Im, Hyungsoon; Kobyakov, A; Moloney, J V

    2009-08-03

    We propose a method of optical data storage that exploits the small dimensions of metallic nano-particles and/or nano-structures to achieve high storage densities. The resonant behavior of these particles (both individually and in small clusters) in the presence of ultraviolet, visible, and near-infrared light may be used to retrieve pre-recorded information by far-field spectroscopic optical detection. In plasmonic data storage, a very short (approximately few femtoseconds) laser pulse is focused to a diffraction-limited spot over a small region of an optical disk containing metallic nano-structures. The digital data stored in each bit-cell, comprising multiple bits of information, modifies the spectrum of the incident light pulse. This spectrum is subsequently detected, upon reflection/transmission, with the aid of an optical spectrum analyzer. We present theoretical as well as preliminary experimental results that confirm the potential of plasmonic nano-structures for high-density optical data storage applications.

  1. Bacteriorhodopsin films for optical signal processing and data storage

    NASA Technical Reports Server (NTRS)

    Walkup, John F. (Principal Investigator); Mehrl, David J. (Principal Investigator)

    1996-01-01

    This report summarizes the research results obtained on NASA Ames Grant NAG 2-878 entitled 'Investigations of Bacteriorhodopsin Films for Optical Signal Processing and Data Storage.' Specifically we performed research, at Texas Tech University, on applications of Bacteriorhodopisin film to both (1) dynamic spatial filtering and (2) holographic data storage. In addition, measurements of the noise properties of an acousto-optical matrix-vestor multiplier built for NASA Ames by Photonic Systems Inc. were performed at NASA Ames' Photonics Laboratory. This research resulted in two papers presented at major optical data processing conferences and a journal paper which is to appear in APPLIED OPTICS. A new proposal for additional BR research has recently been submitted to NASA Ames Research Center.

  2. Holographic diversity interferometry for optical storage.

    PubMed

    Okamoto, Atsushi; Kunori, Keisuke; Takabayashi, Masanori; Tomita, Akihisa; Sato, Kunihiro

    2011-07-04

    This study proposes holographic diversity interferometry (HDI), a system that combines information from spatially dispersed plural image sensors to reconstruct complex amplitude distributions of light signals. HDI can be used to generate four holographic interference fringes having different phases, thus enabling optical phase detection in a single measurement. Unlike conventional phase-shifting digital holography, this system does not require piezoelectric elements and phase shift arrays. In order to confirm the effectiveness of HDI, we generated optical signals having multilevel phases and amplitudes by using two SLMs and performed an experiment for detection and demodulation with HDI.

  3. Micro-optic lens for data storage

    NASA Technical Reports Server (NTRS)

    Milster, T. D.; Trusty, R. M.; Wang, M. S.; Froehlich, F. F.; Erwin, J. Kevin

    1991-01-01

    A new type of microlens for data storage applications that has improved off-axis performance is described. The lens consists of a micro Fresnel pattern on a curved substrate. The radius of the substrate is equal to the focal length of the lens. If the pattern and substrate are thin, the combination satisfies the Abbe sine condition. Therefore, the lens is free of coma. We analyze a 0.5 numerical aperture, 0.50 mm focal length lens in detail. A 0.16 numerical aperture lens was fabricated holographically, and results are presented.

  4. Optical Disk for Digital Storage and Retrieval Systems.

    ERIC Educational Resources Information Center

    Rose, Denis A.

    1983-01-01

    Availability of low-cost digital optical disks will revolutionize storage and retrieval systems over next decade. Three major factors will effect this change: availability of disks and controllers at low-cost and in plentiful supply; availability of low-cost and better output means for system users; and more flexible, less expensive communication…

  5. Interactive Optical Disc Systems: Part 1: Analog Storage.

    ERIC Educational Resources Information Center

    Hessler, David W.

    1984-01-01

    Details distinction between digital and analog data, advantages of analog storage, and optical disc use to store analog data. Configuration and potential of three levels of laser disc systems are explained. Selection of display devices for use with laser disc systems and accessing audio data are addressed. (Continued in next issue.) (EJS)

  6. Current developments in optical data storage with organic dyes.

    PubMed

    Mustroph, Heinz; Stollenwerk, Manfred; Bressau, Volker

    2006-03-20

    The main motivation for the development of digital data storage has been the improvement in play-back quality and the increase in storage capacity. In 1982 Philips and Sony introduced the first technically and economically successful system based on this-the compact disc (CD) and a compatible player. A very broad diversity of optical data recording formats are available today, and a difference is drawn between prerecorded, recordable, and rewritable media. This Review gives an overview of the systems used, the main features of production, and then concentrates on the properties of the organic dyes that are used in recordable systems. Dyestuffs chemistry has gained the reputation of having become a mature field of activity. Is this prejudice or a justified swan song for dyestuffs chemistry? When applications in optical data storage are considered, it is evident that even today progresses such as CD-R and DVD/R would not be feasible without functional dyes.

  7. Optical distortions in electron/positron storage rings

    SciTech Connect

    Brown, K.L.; Donald, M.; Servranckx, R.

    1983-01-01

    We have studied the optical distortions in the PEP electron/positron storage ring for various optical configurations using the computer programs DIMAT, HARMON, PATRICIA, and TURTLE. The results are shown graphically by tracing several thousand trajectories from one interaction region to the next using TURTLE and by tracing a few selected rays several hundred turns using the programs DIMAT and PATRICIA. The results show an interesting correlation between the calculated optical cleanliness of a particular lattice configuration and the observed operating characteristics of the machine.

  8. Surface-Enhanced Raman Optical Data Storage system

    DOEpatents

    Vo-Dinh, T.

    1991-03-12

    A method and apparatus for a Surface-Enhanced Raman Optical Data Storage (SERODS) System are disclosed. A medium which exhibits the Surface Enhanced Raman Scattering (SERS) phenomenon has data written onto its surface of microenvironment by means of a write-on procedure which disturbs the surface or microenvironment of the medium and results in the medium having a changed SERS emission when excited. The write-on procedure is controlled by a signal that corresponds to the data to be stored so that the disturbed regions on the storage device (e.g., disk) represent the data. After the data is written onto the storage device it is read by exciting the surface of the storage device with an appropriate radiation source and detecting changes in the SERS emission to produce a detection signal. The data is then reproduced from the detection signal. 5 figures.

  9. Surface-enhanced raman optical data storage system

    DOEpatents

    Vo-Dinh, Tuan

    1991-01-01

    A method and apparatus for a Surface-Enhanced Raman Optical Data Storage (SERODS) System is disclosed. A medium which exhibits the Surface Enhanced Raman Scattering (SERS) phenomenon has data written onto its surface of microenvironment by means of a write-on procedure which disturbs the surface or microenvironment of the medium and results in the medium having a changed SERS emission when excited. The write-on procedure is controlled by a signal that corresponds to the data to be stored so that the disturbed regions on the storage device (e.g., disk) represent the data. After the data is written onto the storage device it is read by exciting the surface of the storage device with an appropriate radiation source and detecting changes in the SERS emission to produce a detection signal. The data is then reproduced from the detection signal.

  10. Read stability in magneto-optical storage

    NASA Astrophysics Data System (ADS)

    Yardy, R.; Finkelstein, Blair I.; McDaniel, Terry W.

    1990-08-01

    The stability of the read-back signal from an magneto-optical (MO) disk system was investigated as a function of read power, bias field, temperature, and number of read passes. At 2 mW read power and with the bias field turned "on," signal amplitude and jitter degraded markedly at the upper end of the American National Standards Institute (ANSI) temperature range. Signal amplitude erasure depends on bias field and peak temperature of the active layer. Jitter, however, is also dependent on the thermal gradients in the active layer.

  11. Method and apparatus for bistable optical information storage for erasable optical disks

    DOEpatents

    Land, Cecil E.; McKinney, Ira D.

    1990-01-01

    A method and an optical device for bistable storage of optical information, together with reading and erasure of the optical information, using a photoactivated shift in a field dependent phase transition between a metastable or a bias-stabilized ferroelectric (FE) phase and a stable antiferroelectric (AFE) phase in an lead lanthanum zirconate titanate (PLZT). An optical disk contains the PLZT. Writing and erasing of optical information can be accomplished by a light beam normal to the disk. Reading of optical information can be accomplished by a light beam at an incidence angle of 15 to 60 degrees to the normal of the disk.

  12. Method and apparatus for bistable optical information storage for erasable optical disks

    DOEpatents

    Land, C.E.; McKinney, I.D.

    1988-05-31

    A method and an optical device for bistable storage of optical information, together with reading and erasure of the optical information, using a photoactivated shift in a field dependent phase transition between a metastable or a bias-stabilized ferroelectric (FE) phase and a stable antiferroelectric (AFE) phase in a lead lanthanum zirconate titanate (PLZT). An optical disk contains the PLZT. Writing and erasing of optical information can be accomplished by a light beam normal to the disk. Reading of optical information can be accomplished by a light beam at an incidence angle of 15 to 60 degrees to the normal of the disk. 10 figs.

  13. Multichanneled puzzle-like encryption

    NASA Astrophysics Data System (ADS)

    Amaya, Dafne; Tebaldi, Myrian; Torroba, Roberto; Bolognini, Néstor

    2008-07-01

    In order to increase data security transmission we propose a multichanneled puzzle-like encryption method. The basic principle relies on the input information decomposition, in the same way as the pieces of a puzzle. Each decomposed part of the input object is encrypted separately in a 4 f double random phase mask architecture, by setting the optical parameters in a determined status. Each parameter set defines a channel. In order to retrieve the whole information it is necessary to properly decrypt and compose all channels. Computer simulations that confirm our proposal are presented.

  14. Magneto-optic data storage in the '90s

    NASA Astrophysics Data System (ADS)

    Funkenbusch, Arnold W.

    1991-03-01

    Introduction of rewritable optical drives and disks during the late 1980's expanded the range of data storage applications for which optical recording is a preferred technology. The high density and reliability intrinsic in optical recording are combined with the ability to erase and rewrite data as in magnetic recording. Since it does not require flying a magnetic head in proximity to the media surface, rewritable optical media is removable and the risk of damage by a head crash or multiple uses is eliminated. Data can be written, read, erased, and rewritten millions of times without damage. Magneto optic (MO) recording is used in rewritable optical drives/media due to the advantages in speed and durability it offers relative to other methods (phase change, physical changes in polymers). MO drives and media are now available from several companies worldwide. 3M is a major supplier of media (disks) which are produced at it's Vadnais Heights, Minnesota facility. Each media cartridge offers 650MBytes of removable data storage on a two sided 130mm disk.

  15. Diffused holographic information storage and retrieval using photorefractive optical materials

    NASA Astrophysics Data System (ADS)

    McMillen, Deanna Kay

    Holography offers a tremendous opportunity for dense information storage, theoretically one bit per cubic wavelength of material volume, with rapid retrieval, of up to thousands of pages of information simultaneously. However, many factors prevent the theoretical storage limit from being reached, including dynamic range problems and imperfections in recording materials. This research explores new ways of moving closer to practical holographic information storage and retrieval by altering the recording materials, in this case, photorefractive crystals, and by increasing the current storage capacity while improving the information retrieved. As an experimental example of the techniques developed, the information retrieved is the correlation peak from an optical recognition architecture, but the materials and methods developed are applicable to many other holographic information storage systems. Optical correlators can potentially solve any signal or image recognition problem. Military surveillance, fingerprint identification for law enforcement or employee identification, and video games are but a few examples of applications. A major obstacle keeping optical correlators from being universally accepted is the lack of a high quality, thick (high capacity) holographic recording material that operates with red or infrared wavelengths which are available from inexpensive diode lasers. This research addresses the problems from two positions: find a better material for use with diode lasers, and reduce the requirements placed on the material while maintaining an efficient and effective system. This research found that the solutions are new dopants introduced into photorefractive lithium niobate to improve wavelength sensitivities and the use of a novel inexpensive diffuser that reduces the dynamic range and optical element quality requirements (which reduces the cost) while improving performance. A uniquely doped set of 12 lithium niobate crystals was specified and

  16. Electron trapping optical data storage system and applications

    NASA Technical Reports Server (NTRS)

    Brower, Daniel; Earman, Allen; Chaffin, M. H.

    1993-01-01

    A new technology developed at Optex Corporation out-performs all other existing data storage technologies. The Electron Trapping Optical Memory (ETOM) media stores 14 gigabytes of uncompressed data on a single, double-sided 130 mm disk with a data transfer rate of up to 120 megabits per second. The disk is removable, compact, lightweight, environmentally stable, and robust. Since the Write/Read/Erase (W/R/E) processes are carried out photonically, no heating of the recording media is required. Therefore, the storage media suffers no deleterious effects from repeated W/R/E cycling. This rewritable data storage technology has been developed for use as a basis for numerous data storage products. Industries that can benefit from the ETOM data storage technologies include: satellite data and information systems, broadcasting, video distribution, image processing and enhancement, and telecommunications. Products developed for these industries are well suited for the demanding store-and-forward buffer systems, data storage, and digital video systems needed for these applications.

  17. Bloch FDTD simulation of slow optical wave resonance cavity in optical storage technology

    NASA Astrophysics Data System (ADS)

    Zhang, Bin; Lin, Zhaohua; Cai, Lihua

    2013-08-01

    Long chain series resonance cavity is suitable for transferring slow optical wave, which can be served as the basic device for optical storage technology. Micro-ring resonator is one kind of such a long chain structure, which is considered to be the basic component of optical integrated circuit and optical computer in the future. The discrete energy level has the potential to distinguish digital optical data. The optical delay characteristics make such a device possible to store the information for some time. The advantage of this device is that it has the potential to construct an optical storage device in small geometrical dimension and could use mature semiconductor manufacture capability to lower the design and manufacturing expenses. Many experimental results have proved a lot of material and geometrical coefficients are very important for such an optical delay device. New theory method is needed to calculate the periodical energy transfer and time delay characteristics, which can be compared with experimental result. The Bloch FDTD is presented for analysis of such a new optical device, based on the optical Bloch energy band theory. The energy band characteristics of micro-ring periodical optical waveguide device is discussed used that analytical method. This precise calculated method could be served as a useful tool for design the structure of such resonance cavity to achieve desired slow optical wave transfer performance.

  18. SERODS optical data storage with parallel signal transfer

    DOEpatents

    Vo-Dinh, Tuan

    2003-06-24

    Surface-enhanced Raman optical data storage (SERODS) systems having increased reading and writing speeds, that is, increased data transfer rates, are disclosed. In the various SERODS read and write systems, the surface-enhanced Raman scattering (SERS) data is written and read using a two-dimensional process called parallel signal transfer (PST). The various embodiments utilize laser light beam excitation of the SERODS medium, optical filtering, beam imaging, and two-dimensional light detection. Two- and three-dimensional SERODS media are utilized. The SERODS write systems employ either a different laser or a different level of laser power.

  19. SERODS optical data storage with parallel signal transfer

    DOEpatents

    Vo-Dinh, Tuan

    2003-09-02

    Surface-enhanced Raman optical data storage (SERODS) systems having increased reading and writing speeds, that is, increased data transfer rates, are disclosed. In the various SERODS read and write systems, the surface-enhanced Raman scattering (SERS) data is written and read using a two-dimensional process called parallel signal transfer (PST). The various embodiments utilize laser light beam excitation of the SERODS medium, optical filtering, beam imaging, and two-dimensional light detection. Two- and three-dimensional SERODS media are utilized. The SERODS write systems employ either a different laser or a different level of laser power.

  20. Benjamin Banneker's Mathematical Puzzles.

    ERIC Educational Resources Information Center

    Mahoney, John F.

    2003-01-01

    Benjamin Banneker, a self-taught African American mathematician, kept a journal containing a number of mathematical puzzles. Explores four of these puzzles, 200 years later, with the aid of 21st century technology. (Author/NB)

  1. Benjamin Banneker's Mathematical Puzzles.

    ERIC Educational Resources Information Center

    Mahoney, John F.

    2003-01-01

    Benjamin Banneker, a self-taught African American mathematician, kept a journal containing a number of mathematical puzzles. Explores four of these puzzles, 200 years later, with the aid of 21st century technology. (Author/NB)

  2. Surface-enhanced raman optical data storage system

    DOEpatents

    Vo-Dinh, Tuan

    1994-01-01

    An improved Surface-Enhanced Raman Optical Data Storage System (SERODS) is disclosed. In the improved system, entities capable of existing in multiple reversible states are present on the storage device. Such entities result in changed Surface-Enhanced Raman Scattering (SERS) when localized state changes are effected in less than all of the entities. Therefore, by changing the state of entities in localized regions of a storage device, the SERS emissions in such regions will be changed. When a write-on device is controlled by a data signal, such a localized regions of changed SERS emissions will correspond to the data written on the device. The data may be read by illuminating the surface of the storage device with electromagnetic radiation of an appropriate frequency and detecting the corresponding SERS emissions. Data may be deleted by reversing the state changes of entities in regions where the data was initially written. In application, entities may be individual molecules which allows for the writing of data at the molecular level. A read/write/delete head utilizing near-field quantum techniques can provide for a write/read/delete device capable of effecting state changes in individual molecules, thus providing for the effective storage of data at the molecular level.

  3. Surface-Enhanced Raman Optical Data Storage system

    DOEpatents

    Vo-Dinh, T.

    1994-06-28

    An improved Surface-Enhanced Raman Optical Data Storage System (SERODS) is disclosed. In the improved system, entities capable of existing in multiple reversible states are present on the storage device. Such entities result in changed Surface-Enhanced Raman Scattering (SERS) when localized state changes are effected in less than all of the entities. Therefore, by changing the state of entities in localized regions of a storage device, the SERS emissions in such regions will be changed. When a write-on device is controlled by a data signal, such a localized regions of changed SERS emissions will correspond to the data written on the device. The data may be read by illuminating the surface of the storage device with electromagnetic radiation of an appropriate frequency and detecting the corresponding SERS emissions. Data may be deleted by reversing the state changes of entities in regions where the data was initially written. In application, entities may be individual molecules which allows for the writing of data at the molecular level. A read/write/delete head utilizing near-field quantum techniques can provide for a write/read/delete device capable of effecting state changes in individual molecules, thus providing for the effective storage of data at the molecular level. 18 figures.

  4. Information storage and retrieval for probe storage using optical diffraction patterns

    NASA Astrophysics Data System (ADS)

    van Honschoten, Joost W.; de Jong, Henri W.; Koelmans, Wabe W.; Parnell, Thomas P.; Zaboronski, Oleg

    2011-11-01

    A method for fast information retrieval from a probe storage device is considered. It is shown that information can be stored and retrieved using the optical diffraction patterns obtained by the illumination of a large array of cantilevers by a monochromatic light source. In thermo-mechanical probe storage, the information is stored as a sequence of indentations on the polymer medium. To retrieve the information, the array of probes is actuated by applying a bending force to the cantilevers. Probes positioned over indentations experience deflection by the depth of the indentation, probes over the flat media remain un-deflected. Thus the array of actuated probes can be viewed as an irregular optical grating, which creates a data-dependent diffraction pattern when illuminated by laser light. We develop a low complexity modulation scheme, which allows the extraction of information stored in the pattern of indentations on the media from Fourier coefficients of the intensity of the diffraction pattern. We then derive a low-complexity maximum-likelihood sequence detection algorithm for retrieving the user information from the Fourier coefficients. The derivation of both the modulation and the detection schemes is based on the Fraunhofer formula for data-dependent diffraction patterns. The applicability of Fraunhofer diffraction theory to the optical set-up relevant for probe storage is established both theoretically and experimentally. We confirm the potential of the optical readout technique by demonstrating that the impairment characteristics of probe storage channels (channel noise, global positioning errors, small indentation depth) do not lead to an unacceptable increase in data recovery error rates. We also show that for as long as the Fresnel number F ≤ 0.1, the optimal channel detector derived from Fraunhofer diffraction theory does not suffer any significant performance degradation.

  5. Experimental determination of storage ring optics using orbit response measurements

    NASA Astrophysics Data System (ADS)

    Safranek, J.

    1997-02-01

    The measured response matrix giving the change in orbit at beam position monitors (BPMs) with changes in steering magnet excitation can be used to accurately calibrate the linear optics in an electron storage ring [1-8]. A computer code called LOCO (Linear Optics from Closed Orbits) was developed to analyze the NSLS X-Ray Ring measured response matrix to determine: the gradients in all 56 quadrupole magnets; the calibration of the steering magnets and BPMs; the roll of the quadrupoles, steering magnets, and BPMs about the electron beam direction; the longitudinal magnetic centers of the orbit steering magnets; the horizontal dispersion at the orbit steering magnets; and the transverse mis-alignment of the electron orbit in each of the sextupoles. Random orbit measurement error from the BPMs propagated to give only 0.04% rms error in the determination of individual quadrupole gradients and 0.4 mrad rms error in the determination of individual quadrupole rolls. Small variations of a few parts in a thousand in the quadrupole gradients within an individual family were resolved. The optics derived by LOCO gave accurate predictions of the horizontal dispersion, the beta functions, and the horizontal and vertical emittances, and it gave good qualitative agreement with the measured vertical dispersion. The improved understanding of the X-Ray Ring has enabled us to increase the synchrotron radiation brightness. The LOCO code can also be used to find the quadrupole family gradients that best correct for gradient errors in quadrupoles, in sextupoles, and from synchrotron radiation insertion devices. In this way the design periodicity of a storage ring's optics can be restored. An example of periodicity restoration will be presented for the NSLS VUV Ring. LOCO has also produced useful results when applied to the ALS storage ring [8].

  6. Synthesis & Studies of New Non-Destructive Read-Out Materials for Optical Storage and Optical Switches

    DTIC Science & Technology

    2005-12-31

    studied This organic storage system, consists of two different molecular components chemically bonded to each other, a polar photochromic fulgimide...and an oxazine dye, to form a composite molecule that retains the photochromic and spectroscopic properties of each individual molecular component yet...15. NUMBER OF PAGES Optical Storage media, Non-destructive readout materials, 20 3D optical storage, Photochromic composite molecule, Optical 16

  7. Optical Disc Utilized As A Data Storage System For Reconnaissance

    NASA Astrophysics Data System (ADS)

    Herzog, Donald G.

    1984-01-01

    Electra-optic and Radar sensing reconnaissance systems have many advantages including remote transmission and image data processing that conventional film camera systems do not have. However, data storage and retrieval that was naturally and easily accomplished with film must now be accommodated by other techniques. The optical disc data storage and retrieval systems offer significant advantage towards fulfilling this need. This paper will provide an overview description of the technology, some of the fundamental alternatives of configuration approach, and some examples of where it may be considered in the reconnaissance system. Silver halide film has been and still is the work horse of the image based reconnaissance field. It will not be replaced in the near future either, but rather a gradual transition to total electronic systems is expected. It is not the intent of this paper to debase film, because in fact it has its advantages. We have learned to optimize its advantages and minimize its disadvantages. However optical disc systems have a definite role to play in the reconnaissance field.

  8. Rewritable three-dimensional holographic data storage via optical forces

    SciTech Connect

    Yetisen, Ali K.; Montelongo, Yunuen; Butt, Haider

    2016-08-08

    The development of nanostructures that can be reversibly arranged and assembled into 3D patterns may enable optical tunability. However, current dynamic recording materials such as photorefractive polymers cannot be used to store information permanently while also retaining configurability. Here, we describe the synthesis and optimization of a silver nanoparticle doped poly(2-hydroxyethyl methacrylate-co-methacrylic acid) recording medium for reversibly recording 3D holograms. We theoretically and experimentally demonstrate organizing nanoparticles into 3D assemblies in the recording medium using optical forces produced by the gradients of standing waves. The nanoparticles in the recording medium are organized by multiple nanosecond laser pulses to produce reconfigurable slanted multilayer structures. We demonstrate the capability of producing rewritable optical elements such as multilayer Bragg diffraction gratings, 1D photonic crystals, and 3D multiplexed optical gratings. We also show that 3D virtual holograms can be reversibly recorded. This recording strategy may have applications in reconfigurable optical elements, data storage devices, and dynamic holographic displays.

  9. Rewritable three-dimensional holographic data storage via optical forces

    NASA Astrophysics Data System (ADS)

    Yetisen, Ali K.; Montelongo, Yunuen; Butt, Haider

    2016-08-01

    The development of nanostructures that can be reversibly arranged and assembled into 3D patterns may enable optical tunability. However, current dynamic recording materials such as photorefractive polymers cannot be used to store information permanently while also retaining configurability. Here, we describe the synthesis and optimization of a silver nanoparticle doped poly(2-hydroxyethyl methacrylate-co-methacrylic acid) recording medium for reversibly recording 3D holograms. We theoretically and experimentally demonstrate organizing nanoparticles into 3D assemblies in the recording medium using optical forces produced by the gradients of standing waves. The nanoparticles in the recording medium are organized by multiple nanosecond laser pulses to produce reconfigurable slanted multilayer structures. We demonstrate the capability of producing rewritable optical elements such as multilayer Bragg diffraction gratings, 1D photonic crystals, and 3D multiplexed optical gratings. We also show that 3D virtual holograms can be reversibly recorded. This recording strategy may have applications in reconfigurable optical elements, data storage devices, and dynamic holographic displays.

  10. Photodimerization in dipeptides for high capacity optical digital storage

    SciTech Connect

    Ramanujam, P.S.; Berg, Rolf H.

    2004-09-06

    We have developed peptide materials with chromophores that undergo cycloaddition, suitable for terabit optical digital storage in a 5.25 in. disc. The rationale behind this design is that the length and rigidity of the backbone can be adjusted to facilitate the formation of a photodimer without large physical movements of the chromophores on exposure to UV light. Initially strongly absorbing films transmit up to 50% of light on irradiation at dimerizing wavelengths. This property can be utilized to record grey levels. An intensity-dependent transmission behavior has been observed that may enable data to be written and read at the same wavelength.

  11. Optical properties of a photopolymer film for digital holographic storage

    NASA Astrophysics Data System (ADS)

    Shin, Changwon; Kim, Junghoi; Kim, Nam; Lee, Hyojin; Kim, Eunkyoung

    2005-09-01

    Tir- and mono functional monomers were dispersed in a solution of polysulfone in organic solvent containing a photo initiator and other additives. New photopolymer film was prepared by dispersing acrylic monomer in a polysulfone matrix. The Polysulfone was adopted as a binder since it affords transparent thick films with low dimensional changes during holographic recording. Optical property of the photopolymer showed high diffraction efficiency (>90%) under an optimized optical condition at 532nm laser. The angular selectivity for angular multiplexing page oriented holographic memories (POHMs), the maximum diffraction efficiency of the material during holographic recording, the diffraction efficiency of the films as a function of an incident angle of two beams, exposure energy for saturation of the holographic material and application for holographic data storage will be discussed.

  12. Health information management using optical storage technology: case studies.

    PubMed

    Kohn, D

    1992-05-01

    All the health care facilities examined in the case studies addressed several important organizational issues before and during the installation of their systems. All the facilities examined employee commitment. The prudent managers considered how easily their employees adapt to changes in their jobs and work environment. They considered how enthusiastic cooperation can be fostered in the creation of a liberated and reengineered office. This was determined not only by each individual's reaction to change, but also by the health care facility's track record with other system installations. For example, document image, diagnostic image, and coded data processing systems allow the integration of divergent health care information systems within complex institutions. Unfortunately, many institutions are currently struggling with how to create an information management architecture that will integrate their mature systems, such as their patient care and financial systems. Information managers must realize that if optical storage technology-based systems are used in a strategic and planned fashion, these systems can act as focal points for systems integration, not as promises to further confuse the issue. Another issue that needed attention in all the examples was the work environment. The managers considered how the work environment was going to affect the ability to integrate optical image and data systems into the institution. For example, many of these medical centers have created alliances with clinics, HMOs, and large corporate users of medical services. This created a demand for all or part of the health information outside the confines of the original institution. Since the work environment is composed of a handful of factors such as merged medical services, as many work environment factors as possible were addressed before application of the optical storage technology solution in the institutions. And finally, the third critical issue was the organization of work

  13. Eternal 5D optical data storage in glass (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Kazansky, Peter G.; Cerkauskaite, Ausra; Drevinskas, Rokas; Zhang, Jingyu

    2016-09-01

    A decade ago it has been discovered that during femtosecond laser writing self-organized subwavelength structures with record small features of 20 nm, could be created in the volume of silica glass. On the macroscopic scale the self-assembled nanostructure behaves as a uniaxial optical crystal with negative birefringence. The optical anisotropy, which results from the alignment of nano-platelets, referred to as form birefringence, is of the same order of magnitude as positive birefringence in crystalline quartz. The two independent parameters describing birefringence, the slow axis orientation (4th dimension) and the strength of retardance (5th dimension), are explored for the optical encoding of information in addition to three spatial coordinates. The slow axis orientation and the retardance are independently manipulated by the polarization and intensity of the femtosecond laser beam. The data optically encoded into five dimensions is successfully retrieved by quantitative birefringence measurements. The storage allows unprecedented parameters including hundreds of terabytes per disc data capacity and thermal stability up to 1000°. Even at elevated temperatures of 160oC, the extrapolated decay time of nanogratings is comparable with the age of the Universe - 13.8 billion years. The recording of the digital documents, which will survive the human race, including the eternal copies of Universal Declaration of Human Rights, Newton's Opticks, Kings James Bible and Magna Carta, is a vital step towards an eternal archive. Additionally, a number of projects (such as Time Capsule to Mars, MoonMail, and the Google Lunar XPRIZE) could benefit from the technique's extreme durability, which fulfills a crucial requirement for storage on the Moon or Mars.

  14. The Proton Radius Puzzle

    NASA Astrophysics Data System (ADS)

    Downie, E. J.

    2016-03-01

    The proton radius puzzle is the difference between the proton radius as measured with electron scattering and in the excitation spectrum of atomic hydrogen, and that measured with muonic hydrogen spectroscopy. Since the inception of the proton radius puzzle in 2010 by the measurement of Pohl et al.[1], many possible resolutions to the puzzle have been postulated, but, to date, none has been generally accepted. New data are therefore necessary to resolve the issue. We briefly review the puzzle, the proposed solutions, and the new electron scattering and spectroscopy experiments planned and underway. We then introduce the MUSE experiment, which seeks to resolve the puzzle by simultaneously measuring elastic electron and muon scattering on the proton, in both charge states, thereby providing new information to the puzzle. MUSE addresses issues of two-photon effects, lepton universality and, possibly, new physics, while providing simultaneous form factor, and therefore radius, measurements with both muons and electrons.

  15. Laser Card For Compact Optical Data Storage Systems

    NASA Astrophysics Data System (ADS)

    Drexler, Jerome

    1982-05-01

    The principal thrust of the optical data storage industry to date has been the 10 billion bit optical disc system. Mass memory has been the primary objective. Another objective that is beginning to demand recognition is compact memory of 1 million to 40 million bits--on a wallet-size, laser recordable card. Drexler Technology has addressed this opportunity and has succeeded in demonstrating laser writing and readback using a 16 mm by 85 mm recording stripe mounted on a card. The write/read apparatus was developed by SRI International. With this unit, 5 micron holes have been recorded using a 10 milliwatt, 830 nanometer semiconductor-diode laser. Data is entered on an Apple II keyboard using the ASCII code. The recorded reflective surface is scanned with the same laser at lower power to generate a reflected bit stream which is converted into alphanumerics and which appear on the monitor. We are pleased to report that the combination of the DREXONTM laser recordable card ("Laser Card"), the semiconductor-diode laser, arrays of large recorded holes, and human interactive data rates are all mutually compatible and point the way forward to economically feasible, compact, data-storage systems.

  16. Puzzling Ways to Learn

    ERIC Educational Resources Information Center

    School Shop, 1975

    1975-01-01

    Four authors present crossword and wordfind puzzles developed for students in the areas of electricity, principles of hydraulics, finishing, construction, thermoplastic materials, patternmaking, wood, occupations, and drafting. (BP)

  17. Puzzling Ways to Learn

    ERIC Educational Resources Information Center

    School Shop, 1975

    1975-01-01

    Four authors present crossword and wordfind puzzles developed for students in the areas of electricity, principles of hydraulics, finishing, construction, thermoplastic materials, patternmaking, wood, occupations, and drafting. (BP)

  18. The puzzling afterglow of GRB 050721: a rebrightening seen in the optical but not in the X-ray

    SciTech Connect

    Antonelli, L. A.; Romano, P.; Testa, V.; D'Elia, V.; Guetta, D.; Torii, K.; Malesani, D.

    2007-08-21

    We present here the analysis of the early and late multiwavelength afterglow emission, as observed by Swift a small robotic telescope, and the VLT. We compare early observations with late afterglow observations obtained with Swift and the VLT and we observe an intense rebrightening in the optical band at about one day after the burst which is not present in the X-ray band. The lack of detection in X-ray of such a strong rebrightening at lower energies may be described with a variable external density profile. In such a scenario, the combined X-ray and optical observations allow us to derive that the matter density located at {approx} 1017 cm from the burst is about a factor of 10 higher than in the inner region. This is the first time in which a rebrightening has been observed in the optical afterglow of a GRB that is clearly absent in the X-ray afterglow.

  19. SERODS: a new medium for high-density optical data storage

    NASA Astrophysics Data System (ADS)

    Vo-Dinh, Tuan; Stokes, David L.

    1998-10-01

    A new optical dada storage technology based on the surface- enhanced Raman scattering (SERS) effect has been developed for high-density optical memory and three-dimensional data storage. With the surface-enhanced Raman optical data storage (SERODS) technology, the molecular interactions between the optical layer molecules and the nanostructured metal substrate are modified by the writing laser, changing their SERS properties to encode information as bits. Since the SERS properties are extremely sensitive to molecular nano- environments, very small 'spectrochemical holes' approaching the diffraction limit can be produced for the writing process. The SERODS device uses a reading laser to induce the SERS emission of molecules on the disk and a photometric detector tuned to the frequency of the RAMAN spectrum to retrieve the stored information. The results illustrate that SERODS is capable of three-dimensional data storage and has the potential to achieve higher storage density than currently available optical data storage systems.

  20. Invitation to a Puzzle Party.

    ERIC Educational Resources Information Center

    Palmer, Libby

    1980-01-01

    The author describes how her personal interest in puzzles led her to create Puzzle Parties at the College of Santa Fe in New Mexico. Now regular events, these puzzle parties attract several hundred adults and children from the community. (SJL)

  1. Invitation to a Puzzle Party.

    ERIC Educational Resources Information Center

    Palmer, Libby

    1980-01-01

    The author describes how her personal interest in puzzles led her to create Puzzle Parties at the College of Santa Fe in New Mexico. Now regular events, these puzzle parties attract several hundred adults and children from the community. (SJL)

  2. Puzzles and Hunts.

    ERIC Educational Resources Information Center

    Weissblum, Aaron

    2000-01-01

    A company designs and delivers treasure and scavenger hunts for corporate and institutional clients. Groups are divided into teams that must solve puzzles for directions or clues. The hunts build creativity, teamwork, communication skills, and an appreciation of others' strengths. An insert includes a four-puzzle mini-treasure hunt. (TD)

  3. Tangrams: Puzzles of Art

    ERIC Educational Resources Information Center

    Fee, Brenda

    2009-01-01

    Challenging one's brain is the beginning of making great art. Tangrams are a great way to keep students thinking about their latest art project long after leaving the classroom. A tangram is a Chinese puzzle. The earliest known reference to tangrams appears in a Chinese book dated 1813, but the puzzles existed long before that date. The puzzle…

  4. Puzzles and Hunts.

    ERIC Educational Resources Information Center

    Weissblum, Aaron

    2000-01-01

    A company designs and delivers treasure and scavenger hunts for corporate and institutional clients. Groups are divided into teams that must solve puzzles for directions or clues. The hunts build creativity, teamwork, communication skills, and an appreciation of others' strengths. An insert includes a four-puzzle mini-treasure hunt. (TD)

  5. The Anatomy Puzzle Book.

    ERIC Educational Resources Information Center

    Jacob, Willis H.; Carter, Robert, III

    This document features review questions, crossword puzzles, and word search puzzles on human anatomy. Topics include: (1) Anatomical Terminology; (2) The Skeletal System and Joints; (3) The Muscular System; (4) The Nervous System; (5) The Eye and Ear; (6) The Circulatory System and Blood; (7) The Respiratory System; (8) The Urinary System; (9) The…

  6. The Anatomy Puzzle Book.

    ERIC Educational Resources Information Center

    Jacob, Willis H.; Carter, Robert, III

    This document features review questions, crossword puzzles, and word search puzzles on human anatomy. Topics include: (1) Anatomical Terminology; (2) The Skeletal System and Joints; (3) The Muscular System; (4) The Nervous System; (5) The Eye and Ear; (6) The Circulatory System and Blood; (7) The Respiratory System; (8) The Urinary System; (9) The…

  7. Tangrams: Puzzles of Art

    ERIC Educational Resources Information Center

    Fee, Brenda

    2009-01-01

    Challenging one's brain is the beginning of making great art. Tangrams are a great way to keep students thinking about their latest art project long after leaving the classroom. A tangram is a Chinese puzzle. The earliest known reference to tangrams appears in a Chinese book dated 1813, but the puzzles existed long before that date. The puzzle…

  8. Large Format Multifunction 2-Terabyte Optical Disk Storage System

    NASA Technical Reports Server (NTRS)

    Kaiser, David R.; Brucker, Charles F.; Gage, Edward C.; Hatwar, T. K.; Simmons, George O.

    1996-01-01

    The Kodak Digital Science OD System 2000E automated disk library (ADL) base module and write-once drive are being developed as the next generation commercial product to the currently available System 2000 ADL. Under government sponsorship with the Air Force's Rome Laboratory, Kodak is developing magneto-optic (M-O) subsystems compatible with the Kodak Digital Science ODW25 drive architecture, which will result in a multifunction (MF) drive capable of reading and writing 25 gigabyte (GB) WORM media and 15 GB erasable media. In an OD system 2000 E ADL configuration with 4 MF drives and 100 total disks with a 50% ration of WORM and M-O media, 2.0 terabytes (TB) of versatile near line mass storage is available.

  9. Certification of ICI 1012 optical data storage tape

    NASA Technical Reports Server (NTRS)

    Howell, J. M.

    1993-01-01

    ICI has developed a unique and novel method of certifying a Terabyte optical tape. The tape quality is guaranteed as a statistical upper limit on the probability of uncorrectable errors. This is called the Corrected Byte Error Rate or CBER. We developed this probabilistic method because of two reasons why error rate cannot be measured directly. Firstly, written data is indelible, so one cannot employ write/read tests such as used for magnetic tape. Secondly, the anticipated error rates need impractically large samples to measure accurately. For example, a rate of 1E-12 implies only one byte in error per tape. The archivability of ICI 1012 Data Storage Tape in general is well characterized and understood. Nevertheless, customers expect performance guarantees to be supported by test results on individual tapes. In particular, they need assurance that data is retrievable after decades in archive. This paper describes the mathematical basis, measurement apparatus and applicability of the certification method.

  10. A Bibliography of the Literature on Optical Storage Technology. Final Report.

    ERIC Educational Resources Information Center

    Park, James R.

    Compiled to serve as a working tool for those involved in optical storage research, planning, and development, this bibliography contains nearly 700 references related to the optical storage and retrieval of digital computer data. Citations are divided into two major groups covering the general and patent literatures. Each citation includes the…

  11. Blood Type Puzzle.

    ERIC Educational Resources Information Center

    Kelly, Janet

    1997-01-01

    Presents a blood type puzzle that provides a visual, hands-on mechanism by which students can examine blood group reactions. Offers students an opportunity to construct their own knowledge about blood types. (JRH)

  12. Blood Type Puzzle.

    ERIC Educational Resources Information Center

    Kelly, Janet

    1997-01-01

    Presents a blood type puzzle that provides a visual, hands-on mechanism by which students can examine blood group reactions. Offers students an opportunity to construct their own knowledge about blood types. (JRH)

  13. Review of ultra-high density optical storage technologies for big data center

    NASA Astrophysics Data System (ADS)

    Hao, Ruan; Liu, Jie

    2016-10-01

    In big data center, optical storage technologies have many advantages, such as energy saving and long lifetime. However, how to improve the storage density of optical storage is still a huge challenge. Maybe the multilayer optical storage technology is the good candidate for big data center in the years to come. Due to the number of layers is primarily limited by transmission of each layer, the largest capacities of the multilayer disc are around 1 TB/disc and 10 TB/ cartridge. Holographic data storage (HDS) is a volumetric approach, but its storage capacity is also strictly limited by the diffractive nature of light. For a holographic disc with total thickness of 1.5mm, its potential capacities are not more than 4TB/disc and 40TB/ cartridge. In recent years, the development of super resolution optical storage technology has attracted more attentions. Super-resolution photoinduction-inhibition nanolithography (SPIN) technology with 9 nm feature size and 52nm two-line resolution was reported 3 years ago. However, turning this exciting principle into a real storage system is a huge challenge. It can be expected that in the future, the capacities of 10TB/disc and 100TB/cartridge can be achieved. More importantly, due to breaking the diffraction limit of light, SPIN technology will open the door to improve the optical storage capacity steadily to meet the need of the developing big data center.

  14. Flexible storage medium for write-once optical tape

    NASA Technical Reports Server (NTRS)

    Strandjord, Andrew J. G.; Webb, Steven P.; Perettie, Donald J.; Cipriano, Robert A.

    1993-01-01

    A write-once data storage media was developed which is suitable for optical tape applications. The media is manufactured using a continuous film process to deposit a ternary alloy of tin, bismuth, and copper. This laser sensitive layer is sputter deposited onto commercial plastic web as a single-layer thin film. A second layer is sequentially deposited on top of the alloy to enhance the media performance and act as an abrasion resistant hard overcoat. The media was observed to have laser write sensitivities of less than 2.0 njoules/bit, carrier-to-noise levels of greater than 50dB's, modulation depths of approximately 100 percent, read-margins of greater than 35, uniform grain sizes of less than 200 Angstroms, and a media lifetime that exceeds 10 years. Prototype tape media was produced for use in the CREO drive system. The active and overcoat materials are first sputter deposited onto three mil PET film in a single pass through the vacuum coating system, and then converted down into multiple reels of 35mm x 880m tape. One mil PET film was also coated in this manner and then slit and packaged into 3480 tape cartridges.

  15. Flexible storage medium for write-once optical tape

    NASA Technical Reports Server (NTRS)

    Strandjord, Andrew J. G.; Webb, Steven P.; Perettie, Donald J.; Cipriano, Robert A.

    1993-01-01

    A write-once data storage media was developed which is suitable for optical tape applications. The media is manufactured using a continuous film process to deposit a ternary alloy of tin, bismuth, and copper. This laser sensitive layer is sputter deposited onto commercial plastic web as a single-layer thin film. A second layer is sequentially deposited on top of the alloy to enhance the media performance and act as an abrasion resistant hard overcoat. The media was observed to have laser write sensitivities of less than 2.0 njoules/bit, carrier-to-noise levels of greater than 50dB's, modulation depths of approximately 100 percent, read-margins of greater than 35, uniform grain sizes of less than 200 Angstroms, and a media lifetime that exceeds 10 years. Prototype tape media was produced for use in the CREO drive system. The active and overcoat materials are first sputter deposited onto three mil PET film in a single pass through the vacuum coating system, and then converted down into multiple reels of 35mm x 880m tape. One mil PET film was also coated in this manner and then slit and packaged into 3480 tape cartridges.

  16. Turbo Decoding with Run Length Limited Code for Optical Storage

    NASA Astrophysics Data System (ADS)

    Yamada, Eiji; Iwaki, Tetsuo; Yamaguchi, Takeshi

    2002-03-01

    A new turbo decoding method with a run length limited (RLL) code for optical storage is proposed. The system entails a trellis code that joins the RLL code, the non-return-to-zero inverse (NRZI) conversion, and the partial response (PR) channel as the inner code. The inner a posteriori probability (APP) decoder is able to utilize the extrinsic information fed back from the output of the outer decoder. A turbo-coded (1, 7)RLL-constrained PR2 channel was simulated. The full, partial, and serial turbo decoding systems with the inner APP decoder achieved coding gains of 4.7 dB, 4.3 dB, and 3.3 dB, respectively, over the uncoded (1, 7)RLL-constrained PR2 channel at a bit error rate (BER) of 10-5. The full and partial turbos were also improved by 1.2 dB and 0.8 dB, respectively, over the partial turbo with the RLL soft-input soft-output (SISO) decoder at a BER of 10-5.

  17. Delivery of video-on-demand services using local storages within passive optical networks.

    PubMed

    Abeywickrama, Sandu; Wong, Elaine

    2013-01-28

    At present, distributed storage systems have been widely studied to alleviate Internet traffic build-up caused by high-bandwidth, on-demand applications. Distributed storage arrays located locally within the passive optical network were previously proposed to deliver Video-on-Demand services. As an added feature, a popularity-aware caching algorithm was also proposed to dynamically maintain the most popular videos in the storage arrays of such local storages. In this paper, we present a new dynamic bandwidth allocation algorithm to improve Video-on-Demand services over passive optical networks using local storages. The algorithm exploits the use of standard control packets to reduce the time taken for the initial request communication between the customer and the central office, and to maintain the set of popular movies in the local storage. We conduct packet level simulations to perform a comparative analysis of the Quality-of-Service attributes between two passive optical networks, namely the conventional passive optical network and one that is equipped with a local storage. Results from our analysis highlight that strategic placement of a local storage inside the network enables the services to be delivered with improved Quality-of-Service to the customer. We further formulate power consumption models of both architectures to examine the trade-off between enhanced Quality-of-Service performance versus the increased power requirement from implementing a local storage within the network.

  18. Optical Disks Compete with Videotape and Magnetic Storage Media: Part II.

    ERIC Educational Resources Information Center

    Urrows, Henry; Urrows, Elizabeth

    1988-01-01

    Describes capabilities of Digi-Data's high-capacity computer storage tape drive, Gigastore, and FileTek's Storage Machine/1. Optical digital disk (ODD) leaders' reactions, opinions, and new products are reported. A directory of 13 ODD sources is included. (MES)

  19. Optical Disks Compete with Videotape and Magnetic Storage Media: Part I.

    ERIC Educational Resources Information Center

    Urrows, Henry; Urrows, Elizabeth

    1988-01-01

    Describes the latest technology in videotape cassette systems and other magnetic storage devices and their possible effects on optical data disks. Highlights include Honeywell's Very Large Data Store (VLDS); Exabyte's tape cartridge storage system; standards for tape drives; and Masstor System's videotape cartridge system. (LRW)

  20. Optical Disks Compete with Videotape and Magnetic Storage Media: Part II.

    ERIC Educational Resources Information Center

    Urrows, Henry; Urrows, Elizabeth

    1988-01-01

    Describes capabilities of Digi-Data's high-capacity computer storage tape drive, Gigastore, and FileTek's Storage Machine/1. Optical digital disk (ODD) leaders' reactions, opinions, and new products are reported. A directory of 13 ODD sources is included. (MES)

  1. Proton Remains Puzzling

    SciTech Connect

    Gao, Haiyan; Liu, Tianbo; Peng, Chao; Ye, Zhihong; Zhao, Zhiwen

    2015-01-01

    Nucleons are building blocks of visible matter, and are responsible for more than 99% of the visible mass in the universe despite the fact that the discovery of the Higgs boson is almost irrelevant to the origin of the proton mass. While major progress has been made in the last two decades in understanding the proton spin puzzle discovered in the late 1980s by the European Muon Collaboration, a new proton puzzle emerged in the last several years concerning the proton charge radius, which is the charge weighted size of the proton. In this paper we will review the latest situation concerning the proton charge radius, mass and spin, and discuss upcoming new experiments addressing these puzzles, as well as implications for new physics.

  2. Boggle Logic Puzzles: Minimal Solutions

    ERIC Educational Resources Information Center

    Needleman, Jonathan

    2013-01-01

    Boggle logic puzzles are based on the popular word game Boggle played backwards. Given a list of words, the problem is to recreate the board. We explore these puzzles on a 3 x 3 board and find the minimum number of three-letter words needed to create a puzzle with a unique solution. We conclude with a series of open questions.

  3. Musical Traditions. Puzzle Corner.

    ERIC Educational Resources Information Center

    Andrews, Ian A.

    1999-01-01

    Discusses the changes in musical experiences, such as live versus recorded music, as society has developed technologically. Presents a crossword puzzle that focuses on the traditions and musicians of baroque, classical, and romantic music each originating in Europe. Includes the clues and word list. (CMK)

  4. The endodontic diagnostic puzzle.

    PubMed

    Schweitzer, Jordan L

    2009-01-01

    Endodontic diagnosis is the cornerstone of endodontic treatment. Endodontic diagnosis can be likened to a puzzle, where the pieces must be gathered and pieced together before a clinician can see the complete picture. This article discusses how to collect the pieces and fit them together to see the pulpal and periapical diagnosis emerge.

  5. Quebec Nationalism. Puzzle Corner.

    ERIC Educational Resources Information Center

    Andrews, Ian

    1999-01-01

    Addresses the movement called civic nationalism in Quebec Province (Canada) that allows all people regardless of ethnic heritage to participate fully in the secular and governmental life of Canada. Provides a puzzle that focuses on the people uniting against civic nationalism. Included the clues and word list. (CMK)

  6. More Pebble Puzzles.

    ERIC Educational Resources Information Center

    Gibbs, William M.

    This booklet is a collection of puzzles, investigations, and games. They are designed to be used with large objects such as tins or stones and diagrams marked on the ground. The children are to be encouraged to use an experimental, trial-and-error approach at first, and then develop methods of solution. (MNS)

  7. Coherent Optical Memory with High Storage Efficiency and Large Fractional Delay

    NASA Astrophysics Data System (ADS)

    Chen, Yi-Hsin; Lee, Meng-Jung; Wang, I.-Chung; Du, Shengwang; Chen, Yong-Fan; Chen, Ying-Cheng; Yu, Ite A.

    2013-02-01

    A high-storage efficiency and long-lived quantum memory for photons is an essential component in long-distance quantum communication and optical quantum computation. Here, we report a 78% storage efficiency of light pulses in a cold atomic medium based on the effect of electromagnetically induced transparency. At 50% storage efficiency, we obtain a fractional delay of 74, which is the best up-to-date record. The classical fidelity of the recalled pulse is better than 90% and nearly independent of the storage time, as confirmed by the direct measurement of phase evolution of the output light pulse with a beat-note interferometer. Such excellent phase coherence between the stored and recalled light pulses suggests that the current result may be readily applied to single photon wave packets. Our work significantly advances the technology of electromagnetically induced transparency-based optical memory and may find practical applications in long-distance quantum communication and optical quantum computation.

  8. Light storage in a cold atomic ensemble with a high optical depth

    NASA Astrophysics Data System (ADS)

    Park, Kwang-Kyoon; Chough, Young-Tak; Kim, Yoon-Ho

    2017-06-01

    A quantum memory with a high storage efficiency and a long coherence time is an essential element in quantum information applications. Here, we report our recent development of an optical quantum memory with a rubidium-87 cold atom ensemble. By increasing the optical depth of the medium, we have achieved a storage efficiency of 65% and a coherence time of 51 μs for a weak laser pulse. The result of a numerical analysis based on the Maxwell-Bloch equations agrees well with the experimental results. Our result paves the way toward an efficient optical quantum memory and may find applications in photonic quantum information processing.

  9. Optical data storage for high-speed data processing and archiving

    NASA Astrophysics Data System (ADS)

    Boldis, M.; Uherek, F.; Chovan, J.

    2010-12-01

    With the invention of first laser before 50 years has been proved generation of intense, focused and narrow light beam of one wavelength, also at the same time were fulfilled assumptions for creation memories on light base - Optical Data Storages. Contemporary dynamic memories operate on base electrical impulses, manufactured as matrix arranged MOSFET transistors with capacitors, and reach time delay (latency time) in ones nanoseconds. Transfer data rates are above ones of Gbps. Current storages are approaching technologically threshold parameters, what may be barrier to further development, whereas Optical Data storages multiple exceed transfer data rates of contemporary memories, not require reverse O/E/O signal transformation, operate in pico-seconds (ps) and work at low energetic levels of femto- Joules. New end-user services lay still bigger emphasis for transferred and stored data volumes, transfer rates, quality of transmission and data processing, whereby they partly pushing out contemporary storages and create place for optical memory elements used in telecommunication networks and in devices. Optical storages with their several-fold higherdensity, high transmission rates, better quality and small dimensions are becoming a new trend for dynamic buffer or balancing memories, used for long-term data archiving in plasmonic nano-structures within Holographic Data storages.

  10. Nature's Greatest Puzzles

    SciTech Connect

    Quigg, Chris; /Fermilab

    2005-02-01

    It is a pleasure to be part of the SLAC Summer Institute again, not simply because it is one of the great traditions in our field, but because this is a moment of great promise for particle physics. I look forward to exploring many opportunities with you over the course of our two weeks together. My first task in talking about Nature's Greatest Puzzles, the title of this year's Summer Institute, is to deconstruct the premise a little bit.

  11. Analysis and correction of linear optics errors, and operational improvements in the Indus-2 storage ring

    NASA Astrophysics Data System (ADS)

    Husain, Riyasat; Ghodke, A. D.

    2017-08-01

    Estimation and correction of the optics errors in an operational storage ring is always vital to achieve the design performance. To achieve this task, the most suitable and widely used technique, called linear optics from closed orbit (LOCO) is used in almost all storage ring based synchrotron radiation sources. In this technique, based on the response matrix fit, errors in the quadrupole strengths, beam position monitor (BPM) gains, orbit corrector calibration factors etc. can be obtained. For correction of the optics, suitable changes in the quadrupole strengths can be applied through the driving currents of the quadrupole power supplies to achieve the desired optics. The LOCO code has been used at the Indus-2 storage ring for the first time. The estimation of linear beam optics errors and their correction to minimize the distortion of linear beam dynamical parameters by using the installed number of quadrupole power supplies is discussed. After the optics correction, the performance of the storage ring is improved in terms of better beam injection/accumulation, reduced beam loss during energy ramping, and improvement in beam lifetime. It is also useful in controlling the leakage in the orbit bump required for machine studies or for commissioning of new beamlines.

  12. Optical Disk Technology for Large Scale Mass Storage.

    DTIC Science & Technology

    1985-12-01

    rules. It is sufficient to say that the various encoding techniques provide the system’s designer with several advantages. 8. . . .-. ERROR MANAGEMENT ...characterize due to its variable nature. It is not the *intention to dismiss the characterization of the hardware and software for *error management ...system designer. The most difficult step in managing the error budget in an optical disk 2 *system is otingahigh quality media. An optical disk

  13. Chip-Scale Controlled Storage All-Optical Memory

    DTIC Science & Technology

    2007-02-01

    the spectral width in the EIT scheme yields the T2 dephasing time of the two upper states of the “V” system. Since the upper states of our double-V...Express, vol. 13 (24), pp. 9909- 9915 , November 2005. 12. A. V. Uskov and C. Chang-Hasnain, “Slow and superluminal light in semiconductor optical...Quantum-Well Waveguide via Coherent Population Oscillation,” Optics Express 13 (24), pp. 9909- 9915 , Nov. 2005. 8. Phedon Palinginis, Shanna

  14. The non-continuous optical signal identification and data storage on the case of atmospheric disturbances

    NASA Astrophysics Data System (ADS)

    Yu, Si-yuan; Liu, Yong-kai; Ma, Jing; Tan, Li-ying

    2013-08-01

    In the link of satellite to ground laser communication, light signals received by ground terminal receivers are susceptible to interference due to the impact of atmospheric turbulence, and it will result in the degradation of communication quality or even interruption. In this situation, the conventional communication detection device would not be able to analyze the link performance. Thus, it is necessary to develop a set of non-continuous optical signal recognition and storage devices which could work under adverse atmospheric conditions and do the online analysis of the impact of atmospheric on the link of satellite to ground laser. Since the interruption of the optical signal will cause the logical disorders of the high data rate storage system, which uses the CDR output clock as the system clock, general storage device cannot meet the demand of effective storage for communication. In this paper, the usage of FPGA optical signal recovered clock frequency discriminator identified the impact of non-continuous communication signal of atmospheric disturbances effectively. Through the optimization of the system hardware design and software control, we achieved the identification and storage of the laser communication optical signal data while the factor of atmospheric scintillation varying from 0 to 1.5 and the communication data rate being 600Mbps.

  15. Optical residue addition and storage units using a Hughes liquid crystal light valve

    NASA Technical Reports Server (NTRS)

    Habiby, S. F.; Collins, S. A., Jr.

    1984-01-01

    Optical addition and storage units are described in this paper. These units are implemented using the Hughes Liquid Crystal Light Valve (LCLV) as a spatial light modulator using residue arithmetic for a numerical representation. The main hardware components of the design, besides the light valve, include an array of single-mode optical fibers that provide input information, a polarizing prism in combination with quarter-wave and half-wave retarders for residue arithmetic implementation in the adder, and a holographic array for spatial stability in the storage unit.

  16. High-Density Optical Data Storage Enabled by the Photonic Nanojet from a Dielectric Microsphere

    NASA Astrophysics Data System (ADS)

    Kong, Soon-Cheol; Sahakian, Alan V.; Taflove, Allen; Backman, Vadim

    2009-03-01

    We discuss the usage of the photonic nanojet to detect deeply subwavelength pits in a metal substrate for the purpose of high-density optical data storage. Three-dimensional finite-difference time-domain (FDTD) computational solutions of Maxwell's equations are used to analyze and design the system. We find that nanojet-illuminated pits having lateral dimensions of only 100×150 nm2 yield a 40-dB contrast ratio. The FDTD simulation results show that pit-depth modulation and pit-width modulation can significantly increase the optical data-storage capacity.

  17. Digitizing Stereoscopic Optic Nerve Head Photographs for Storage and Viewing Using a Personal Computer

    PubMed Central

    Nesher, Ronit; Zacharopoulos, Ioannis; Assia, Ehud I.; Schuman, Joel S.

    2007-01-01

    Careful examination and monitoring of optic nerve head changes is essential in the treatment of patients with glaucoma. This often results in accumulation of numerous photographs and required appropriate storage space. A simple, inexpensive, and efficient means of storing and viewing stereoscopic optic nerve head photographs is described. Images were acquired with a fundus camera, on a color slide film. Slides were then scanned and digitized. A handheld stereoscope was used for stereoscopic viewing on a computer monitor. A scanning resolution of 300 dpi appeared optimal. At this resolution, the storage utilization was 16 kilobytes and the scanning time was 160 seconds per patient. PMID:16156151

  18. Six-dimensional optical storage utilizing wavelength selective, polarization sensitive, and reflectivity graded Bragg reflectors

    NASA Astrophysics Data System (ADS)

    Liu, Shangqing

    2014-09-01

    An optical storage system which stores data in three spacial and three physical dimensions is designed and investigated. Its feasibility has been demonstrated by theoretical derivation and numerical calculation. This system has comprehensive advantages including very large capacity, ultrafast throughputs, relatively simple structure and compatibility with CD and DVD. It's an actually practicable technology. With two-photon absorption writing/erasing and optical coherence tomography reading, its storage capacity is over 32 Tbytes per DVD sized disk, and its reading speed is over 25 Gbits/s with high signal-to-noise ratio of over 76 dB. The larger capacity of over 1 Pbyte per disk is potential.

  19. Digitizing stereoscopic optic nerve head photographs for storage and viewing using a personal computer.

    PubMed

    Nesher, Ronit; Zacharopoulos, Ioannis; Assia, Ehud I; Schuman, Joel S

    2005-01-01

    Careful examination and monitoring of optic nerve head changes is essential in the treatment of patients with glaucoma. This often results in accumulation of numerous photographs and required appropriate storage space. A simple, inexpensive, and efficient means of storing and viewing stereoscopic optic nerve head photographs is described. Images were acquired with a fundus camera, on a color slide film. Slides were then scanned and digitized. A handheld stereoscope was used for stereoscopic viewing on a computer monitor. A scanning resolution of 300 dpi appeared optimal. At this resolution, the storage utilization was 16 kilobytes and the scanning time was 160 seconds per patient.

  20. Storage and control of optical photons using Rydberg polaritons.

    PubMed

    Maxwell, D; Szwer, D J; Paredes-Barato, D; Busche, H; Pritchard, J D; Gauguet, A; Weatherill, K J; Jones, M P A; Adams, C S

    2013-03-08

    We use a microwave field to control the quantum state of optical photons stored in a cold atomic cloud. The photons are stored in highly excited collective states (Rydberg polaritons) enabling both fast qubit rotations and control of photon-photon interactions. Through the collective read-out of these pseudospin rotations it is shown that the microwave field modifies the long-range interactions between polaritons. This technique provides a powerful interface between the microwave and optical domains, with applications in quantum simulations of spin liquids, quantum metrology and quantum networks.

  1. High-density optical disks for long-term information storage

    NASA Astrophysics Data System (ADS)

    Petrov, Viacheslav; Kryuchyn, Andriy; Gorbov, Ivan

    2011-09-01

    Optical discs are widely used for storage of archival data represented in a digital form. Long-term storage of information recorded on standard CDs is provided by periodical rewriting (once in 3-5 years) on the new carriers. High-stable lightsensitive materials and special reflective metal coatings are proposed to use for increasing the information storage terms of the optical discs. The conducted researches have showed that the application of vitreous chalcogenide semiconductors in optical WORM discs assures the data storage terms up to 30 years. Substantially larger terms of data storage can be realized on the optical ROM carriers. Attainment of the guaranteed data storage terms within several hundreds years is provided in such carriers by applying high-stable materials substrates and information should be represented in the form of a micro-relief structure on the substrate surface. Sapphire, quartz, silicon, glass-ceramics and other materials can be utilized for manufacturing substrates of optical BD discs (and other subsequent high-density disc formats). These materials allow creating substrates characterized with increased melting temperature, chemical and mechanical resistance. Furthermore, using the mentioned materials for substrates production permits applying high temperature materials, such as chrome and nickel, to creation of high-stable refractive layers and demonstrating the sufficient mechanical adhesion between the refractive layer and the substrate. Modern methods of thermo-lithography offers creating of nano-size images on photo-resist layer deposited on the substrates. Those images can be transformed to the nano-size relief structures on the surface of the high-stable materials substrates by techniques of reactive ion-beam etching.

  2. Method of bistable optical information storage using antiferroelectric phase PLZT ceramics

    DOEpatents

    Land, Cecil E.

    1990-01-01

    A method for bistable storage of binary optical information includes an antiferroelectric (AFE) lead lanthanum zirconate titanate (PLZT) layer having a stable antiferroelectric first phase and a ferroelectric (FE) second phase obtained by applying a switching electric field across the surface of the device. Optical information is stored by illuminating selected portions of the layer to photoactivate an FE to AFE transition in those portions. Erasure of the stored information is obtained by reapplying the switching field.

  3. Method of bistable optical information storage using antiferroelectric phase PLZT ceramics

    DOEpatents

    Land, C.E.

    1990-07-31

    A method for bistable storage of binary optical information includes an antiferroelectric (AFE) lead lanthanum zirconate titanate (PLZT) layer having a stable antiferroelectric first phase and a ferroelectric (FE) second phase obtained by applying a switching electric field across the surface of the device. Optical information is stored by illuminating selected portions of the layer to photoactivate an FE to AFE transition in those portions. Erasure of the stored information is obtained by reapplying the switching field. 8 figs.

  4. Efficient synthesis of a new unsymmetrical photochromic diarylethene for optical recording storage

    NASA Astrophysics Data System (ADS)

    Wang, Taofeng; Liu, Gang; Liu, Weijun

    2011-11-01

    A novel unsymmetrical photochromic diarylethene bearing a benzothiazole unit, 1-[ (2,5-dimethyl-3-thienyl) ]-2-[(2-methyl-5-(2-benzothiazole)-3-thienyl)]perfluoroyclopentene (1O) have been synthesized. Its photochromic, fluorescence and optical strorage properties were investigated. The compound exhibited obviously photochromism both in hexane and in PMMA film. In hexane, the fluorescence intensity of 1O declined along with the photochromism upon irradiation with 297 nm light. This new photochromic system also exhibited remarkable optical storage characters.

  5. Efficient synthesis of a new unsymmetrical photochromic diarylethene for optical recording storage

    NASA Astrophysics Data System (ADS)

    Wang, Taofeng; Liu, Gang; Liu, Weijun

    2012-01-01

    A novel unsymmetrical photochromic diarylethene bearing a benzothiazole unit, 1-[ (2,5-dimethyl-3-thienyl) ]-2-[(2-methyl-5-(2-benzothiazole)-3-thienyl)]perfluoroyclopentene (1O) have been synthesized. Its photochromic, fluorescence and optical strorage properties were investigated. The compound exhibited obviously photochromism both in hexane and in PMMA film. In hexane, the fluorescence intensity of 1O declined along with the photochromism upon irradiation with 297 nm light. This new photochromic system also exhibited remarkable optical storage characters.

  6. Optical response of photopolymer materials for holographic data storage applications.

    PubMed

    Sheridan, J T; Gleeson, M R; Close, C E; Kelly, J V

    2007-01-01

    We briefly review the application of photopolymer recording materials in the area of holographic data storage. In particular we discuss the recent development of the Non-local Polymerisation Driven Diffusion model. Applying this model we develop simple first-order analytic expressions describing the spatial frequency response of photopolymer materials. The assumptions made in the derivation of these formulae are described and their ranges of validity are examined. The effects of particular physical parameters of a photopolymer on the material response are discussed.

  7. Unravelling the ORFan Puzzle

    PubMed Central

    Siew, Naomi

    2003-01-01

    ORFans are open reading frames (ORFs) with no detectable sequence similarity to any other sequence in the databases. Each newly sequenced genome contains a significant number of ORFans. Therefore, ORFans entail interesting evolutionary puzzles. However, little can be learned about them using bioinformatics tools, and their study seems to have been underemphasized. Here we present some of the questions that the existence of so many ORFans have raised and review some of the studies aimed at understanding ORFans, their functions and their origins. These works have demonstrated that ORFans are an untapped source of research, requiring further computational and experimental studies. PMID:18629076

  8. A Microscale Oxidation Puzzle

    NASA Astrophysics Data System (ADS)

    Pelter, Michael W.; Macudzinski, Rebecca M.; Passarelli, Mary Ellen

    2000-11-01

    We have adapted oxidation of an alcohol with sodium hypochlorite solution to a "puzzle" approach by using a diol as the substrate for oxidation. The diols under investigation have both a primary and a secondary hydroxyl group. There are three possible outcomes to the reaction: (i) only the primary alcohol is oxidized to the aldehyde (or carboxylic acid); (ii) only the secondary alcohol is oxidized to the ketone; or (iii) both alcohols are oxidized. The assignment is to perform the reaction and determine the structure of the product through interpretation of the IR spectrum. Examples using two commercially available diols are shown.

  9. Pebble Puzzles. A Source Book of Simple Puzzles and Problems.

    ERIC Educational Resources Information Center

    Gibbs, William M.

    This booklet is a collection of puzzles, games, and investigations. All that children need are some stones or shells, on some of which they must write numerals. For playing with the whole class, the game or puzzles may be marked out on the floor or in sand; in that case, larger objects such as small rocks and empty tins may be used. Children are…

  10. Controllable high bandwidth storage of optical information in a Bose-Einstein Condensate

    NASA Astrophysics Data System (ADS)

    Jayaseelan, Maitreyi; Schultz, Justin T.; Murphree, Joseph D.; Hansen, Azure; Bigelow, Nicholas P.

    2016-05-01

    The storage and retrieval of optical information has been of interest for a variety of applications including quantum information processing, quantum networks and quantum memories. Several schemes have been investigated and realized with weak, narrowband pulses, including techniques using EIT in solid state systems and both hot and cold atomic vapors. In contrast, we investigate the storage and manipulation of strong, high bandwidth pulses in a Bose-Einstein Condensate (BEC) of ultracold 87 Rb atoms. As a storage medium for optical pulses, BECs offer long storage times and preserve the coherence properties of the input information, suppressing unwanted thermal decoherence effects. We present numerical simulations of nanosecond pulses addressing a three-level lambda system on the D2 line of 87 Rb. The signal pulse is stored as a localized spin excitation in the condensate and can be moved or retrieved by reapplication of successive control pulses. The relative Rabi frequencies and areas of the pulses and the local atomic density in the condensate determine the storage location and readout of the signal pulse. Extending this scheme to use beams with a variety of spatial modes such as Hermite- and Laguerre-Gaussian modes offers an expanded alphabet for information storage.

  11. Optically Addressed Nanostructures for High Density Data Storage

    DTIC Science & Technology

    2005-10-14

    advanced several approaches to calculate the clique-based capacity of these structures. We have considered and bounded statistical cross-talk between...positioned in the requisite matrix using optical tweezer technologies . This fabrication approach is being analyzed further to understand its limitations... gain -doublet in which a pair of Lorentzian gain lines are used to achieve significant pulse delay relative to a single-line system. A factor of 6.25

  12. The Use of WORM Optical Disc Storage for Newspaper Cuttings in a Public Library.

    ERIC Educational Resources Information Center

    Fulton, Alan R.

    1990-01-01

    Describes the collection of the Local History Department of the Central Library in Aberdeen (which includes 2,300 volumes of locally produced newspapers and 101,000 sheets of press cuttings) and the use of an optical disk system to help solve the problems of storage and access to these materials. (CLB)

  13. Coumarin-Containing Polymers for High Density Non-Linear Optical Data Storage.

    PubMed

    Gindre, Denis; Iliopoulos, Konstantinos; Krupka, Oksana; Evrard, Marie; Champigny, Emilie; Sallé, Marc

    2016-01-26

    Optical data storage was performed with various thin polymer films containing coumarin-based derivatives and by using femtosecond laser pulses as well as two-photon absorption processes. Exploring the photodimerization attribute of coumarin derivatives and using appropriate irradiation wavelengths, recording/erasing processes could be carried out in the same area. Second harmonic generation microscopy was used to read the stored information.

  14. Reversible two-photon optical data storage in coumarin-based copolymers.

    PubMed

    Iliopoulos, Konstantinos; Krupka, Oksana; Gindre, Denis; Sallé, Marc

    2010-10-20

    A functionalized polymer film allowing for a complete and straightforward second-harmonic generation (SHG)-assisted high-contrast writing-reading-erasing-writing sequence is proposed. The whole process is supported by the reversible photoinduced dimerization of a coumarin chromophore and enables efficient optical data storage that can be detected only by SHG imaging.

  15. Implementing Optical Storage: How to Select a Document Image Management System.

    ERIC Educational Resources Information Center

    O'Connor, Mary Ann

    1991-01-01

    Describes document image management systems that are used for optical storage to facilitate information retrieval. Document image management applications are described, considerations in evaluating system features and functions are presented, and criteria for evaluating vendors of document image management systems are suggested. (two references)…

  16. Advanced multilayer optical data storage: origins and future prospect

    NASA Astrophysics Data System (ADS)

    Esener, Sadik

    2008-02-01

    Fifty years have elapsed since the first concepts in volumetric memories have been put forward. Nowadays, the perceived need for low cost removable TB/disk storage systems is one more time fueling the development of 3D media, recording and readout systems. This paper, by reviewing some of the key historic moments and accomplishments in the development of volumetric recording systems attempts to shine light on possible future developments and directions while paying a tribute to many of the researchers that have contributed to the development of this field: in particular to Dr. Hans J. Coufal who for many years has provided vision, guidance, and leadership by leading recent INSIC Technology Roadmap efforts and organizing this conference. He is and will be greatly missed at a time when our common dreams may become a commercial reality.

  17. Three Puzzles for Organic Laboratory.

    ERIC Educational Resources Information Center

    Todd, David; Pickering, Miles

    1988-01-01

    Notes that laboratory work should be more oriented towards puzzle solving rather than technique or illustration. Offers three organic laboratory puzzles which can be solved by melting point alone. Involves lab work at the 100-200-mg scale but still uses conventional glassware. (MVL)

  18. Three Puzzles for Organic Laboratory.

    ERIC Educational Resources Information Center

    Todd, David; Pickering, Miles

    1988-01-01

    Notes that laboratory work should be more oriented towards puzzle solving rather than technique or illustration. Offers three organic laboratory puzzles which can be solved by melting point alone. Involves lab work at the 100-200-mg scale but still uses conventional glassware. (MVL)

  19. Implementation of an optical disk system for medical record storage.

    PubMed

    Mahoney, M E

    1990-09-01

    MARS was a joint developmental effort between Maine Medical Center and Advanced Healthcare Systems, Inc. It has taken nearly three years to get the system (hardware, software, and staff) to a point where it can now meet daily production requirements. This project was truly unique, so there was no opportunity to learn from the experiences of others. The optical disk system has been an attractive solution to some of the problems experienced at Maine Medical Center. The result was worth the effort in terms of both dollars and other less quantifiable benefits that have had a positive impact on patient care.

  20. Optimizing the optical field distribution of near-field SIL optical storage system using five-zone binary phase filters

    NASA Astrophysics Data System (ADS)

    Fang, Chaolong; Zhang, Yaoju; Zhu, Haiyong

    2012-06-01

    Five-zone binary phase filters (FBPFs) are proposed for decreasing the spot size and/or increasing the focal depth of the near-field optical storage system with a hemisphere solid immersion lens (SIL). The design of filters is based on the vector diffraction theory and the MATLAB optimizing toolbox. Three FBPFs with rotationally symmetrical pupil function have been designed, where the one FBPF is for increasing the focal depth as big as possible, the second FBPF is for improving the resolution as high as possible, and the third FBPF integrate the increase of focal depth with the improvement of resolution. Numerical results show that compared with the three-zone amplitude filter, the designed five-zone binary phase-only filters have more prominent performances in improving the focal depth and the resolution of the near-field SIL optical storage system.

  1. New method of two-photon multi-layer optical disc storage

    NASA Astrophysics Data System (ADS)

    Jiang, Bing; Shen, Zhaolong; Cai, Jianwen; Tang, Huohong; Xing, Hui; Huang, Wenhao

    2006-02-01

    Multi-layer data storage based on nonlinear effect caused by two-photon absorption is an attractive approach in the field of mass data storage. A two-photon multi-layer optical disc storage system with disc rotation structure has been proposed. The multi-layer fluorescent disc used in this system consists of three layers. A transparent substrate (under layer) and a thin reflective layer (middle layer) are bonded together forming a kind of structure similar to DVD disc, which is necessary to servo the vertical and radial deviation. Two-photon bits are recorded in top layer. The storage system has two modules: servo module and confocal module. The former keeps following the vertical and radial deviations by means of focusing and tracking servo technologies used in current two-dimensional optical storage devices, so the system can be compatible with CD/DVD. According to the driving signal of actuators in servo pick-up, the confocal module can also follow the disc deviation in both recording and reading processes. The servo module has been finished and the result of preliminary experiment is presented. Using the actuator and the objective lens (NA 0.6) in SANYO pick-up, we successfully recorded and read three data layers in photobleaching material with a homemade femtosecond laser. The layer separation was 15μm and the transverse bit separation was 4 μm.

  2. An emerging network storage management standard: Media error monitoring and reporting information (MEMRI) - to determine optical tape data integrity

    NASA Technical Reports Server (NTRS)

    Podio, Fernando; Vollrath, William; Williams, Joel; Kobler, Ben; Crouse, Don

    1998-01-01

    Sophisticated network storage management applications are rapidly evolving to satisfy a market demand for highly reliable data storage systems with large data storage capacities and performance requirements. To preserve a high degree of data integrity, these applications must rely on intelligent data storage devices that can provide reliable indicators of data degradation. Error correction activity generally occurs within storage devices without notification to the host. Early indicators of degradation and media error monitoring 333 and reporting (MEMR) techniques implemented in data storage devices allow network storage management applications to notify system administrators of these events and to take appropriate corrective actions before catastrophic errors occur. Although MEMR techniques have been implemented in data storage devices for many years, until 1996 no MEMR standards existed. In 1996 the American National Standards Institute (ANSI) approved the only known (world-wide) industry standard specifying MEMR techniques to verify stored data on optical disks. This industry standard was developed under the auspices of the Association for Information and Image Management (AIIM). A recently formed AIIM Optical Tape Subcommittee initiated the development of another data integrity standard specifying a set of media error monitoring tools and media error monitoring information (MEMRI) to verify stored data on optical tape media. This paper discusses the need for intelligent storage devices that can provide data integrity metadata, the content of the existing data integrity standard for optical disks, and the content of the MEMRI standard being developed by the AIIM Optical Tape Subcommittee.

  3. An emerging network storage management standard: Media error monitoring and reporting information (MEMRI) - to determine optical tape data integrity

    NASA Technical Reports Server (NTRS)

    Podio, Fernando; Vollrath, William; Williams, Joel; Kobler, Ben; Crouse, Don

    1998-01-01

    Sophisticated network storage management applications are rapidly evolving to satisfy a market demand for highly reliable data storage systems with large data storage capacities and performance requirements. To preserve a high degree of data integrity, these applications must rely on intelligent data storage devices that can provide reliable indicators of data degradation. Error correction activity generally occurs within storage devices without notification to the host. Early indicators of degradation and media error monitoring 333 and reporting (MEMR) techniques implemented in data storage devices allow network storage management applications to notify system administrators of these events and to take appropriate corrective actions before catastrophic errors occur. Although MEMR techniques have been implemented in data storage devices for many years, until 1996 no MEMR standards existed. In 1996 the American National Standards Institute (ANSI) approved the only known (world-wide) industry standard specifying MEMR techniques to verify stored data on optical disks. This industry standard was developed under the auspices of the Association for Information and Image Management (AIIM). A recently formed AIIM Optical Tape Subcommittee initiated the development of another data integrity standard specifying a set of media error monitoring tools and media error monitoring information (MEMRI) to verify stored data on optical tape media. This paper discusses the need for intelligent storage devices that can provide data integrity metadata, the content of the existing data integrity standard for optical disks, and the content of the MEMRI standard being developed by the AIIM Optical Tape Subcommittee.

  4. Optical phase information writing and storage in populations of metastable quantum states

    SciTech Connect

    Djotyan, G. P.; Sandor, N.; Bakos, J. S.; Soerlei, Zs.

    2009-10-15

    We propose a scheme for robust writing and storage of optical phase information in populations of metastable states of the atoms with a tripod structure of levels by using frequency-chirped laser pulses. The method provides much longer storage times compared with the schemes based on the collective atomic spin coherences. A negligible excitation of the atom provides immunity to decoherence induced by decay of the excited states. The method is robust against small-to-medium variations in the laser pulse intensity and speed of the chirp and, being insensitive to resonance conditions, it is effective both in homogeneously and inhomogeneously broadened media.

  5. Experimental realization of three-color entanglement at optical fiber communication and atomic storage wavelengths.

    PubMed

    Jia, Xiaojun; Yan, Zhihui; Duan, Zhiyuan; Su, Xiaolong; Wang, Hai; Xie, Changde; Peng, Kunchi

    2012-12-21

    Entangled states of light including low-loss optical fiber transmission and atomic resonance frequencies are essential resources for future quantum information networks. We present the experimental achievement on the three-color entanglement generation at 852, 1550, and 1440 nm wavelengths for optical continuous variables. The entanglement generation system consists of two cascaded nondegenerated optical parametric oscillators (NOPOs). The flexible selectivity of nonlinear crystals in the two NOPOs and the tunable property of NOPO provide large freedom for the frequency selection of three entangled optical beams. The presented system will hopefully be developed as a practical entangled source to be used in quantum-information networks with atomic storage units and long fiber transmission lines.

  6. Sleep for Kids: Games and Puzzles

    MedlinePlus

    Games and Puzzles These games and puzzles can help you learn more about sleep! Learn about sleep with this fun crossword puzzle! Test your memory ... can't sleep? • dreams • • bring out the stars • games and puzzles • pj bear booklet • • home • about us • ...

  7. Quantum storage of entangled telecom-wavelength photons in an erbium-doped optical fibre

    NASA Astrophysics Data System (ADS)

    Saglamyurek, Erhan; Jin, Jeongwan; Verma, Varun B.; Shaw, Matthew D.; Marsili, Francesco; Nam, Sae Woo; Oblak, Daniel; Tittel, Wolfgang

    2015-02-01

    The realization of a future quantum Internet requires the processing and storage of quantum information at local nodes and interconnecting distant nodes using free-space and fibre-optic links. Quantum memories for light are key elements of such quantum networks. However, to date, neither an atomic quantum memory for non-classical states of light operating at a wavelength compatible with standard telecom fibre infrastructure, nor a fibre-based implementation of a quantum memory, has been reported. Here, we demonstrate the storage and faithful recall of the state of a 1,532 nm wavelength photon entangled with a 795 nm photon, in an ensemble of cryogenically cooled erbium ions doped into a 20-m-long silica fibre, using a photon-echo quantum memory protocol. Despite its currently limited efficiency and storage time, our broadband light-matter interface brings fibre-based quantum networks one step closer to reality.

  8. Photorefractive Three-Dimensional Disks for Optical Data Storage and Artificial Neural Networks

    NASA Astrophysics Data System (ADS)

    Li, Hsin-Yu Sidney

    This thesis is on the application of 3-D photorefractive crystals disks for holographic optical data storage and optical neural networks. Chapter 1 gives some introductory background and motivation for the materials given in this thesis. In Chapter 2, the coupled-mode analysis and Born's approximation in anisotropic crystals is reviewed. The results are similar to that of isotropic materials. However, there are approximations that are often neglected in the literature. Chapter 3 starts with the description of the holographic 3-D disk for data storage, and analyzes the various alignment errors and tolerance problems for a 3-D disk system. Of particular interest is the effects in image reconstruction caused by rotational angle error. An optimum configuration is found that minimizes this error. Chapter 4 examines the data storage density of 3-D disks and volume holographic storage systems that utilize wavelength/angle and spatial multiplexing. The maximum storage density and the geometry that achieves this density is derived. Chapter 5 discusses the diffraction efficiency of 3-D disks fabricated with photorefractive crystals. Practical geometries and crystal orientations for achieving maximum uniform diffraction efficiency are given and compared to the maximum obtainable diffraction efficiencies using arbitrary cut crystals. Experimental results are shown. Also derived in this chapter are the double grating effect from crystal anisotropy, and the optimum configuration for getting maximum diffraction efficiency using the 90 degree recording geometry. The Khuktarev band-transport model of the photorefractive effect is examined briefly with emphasis on the anisotropy of the material. The proper expression for the permittivity term in the space-charge field formula is derived. Chapter 6 gives an example of an optical neural network that uses photorefractive crystals. It is the real time face-recognition system. The setup and experiments are described. Some properties of

  9. The Puzzling Ophiuchus Stream

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-01-01

    Dwarf galaxies or globular clusters orbiting the Milky Way can be pulled apart by tidal forces, leaving behind a trail of stars known as a stellar stream. One such trail, the Ophiuchus stream, has posed a serious dynamical puzzle since its discovery. But a recent study has identified four stars that might help resolve this streams mystery.Conflicting TimescalesThe stellar stream Ophiuchus was discovered around our galaxy in 2014. Based on its length, which appears to be 1.6 kpc, we can calculate the time that has passed since its progenitor was disrupted and the stream was created: ~250 Myr. But the stars within it are ~12 Gyr old, and the stream orbits the galaxy with a period of ~350 Myr.Given these numbers, we can assume that Ophiuchuss progenitor completed many orbits of the Milky Way in its lifetime. So why would it only have been disrupted 250 million years ago?Fanning StreamLed by Branimir Sesar (Max Planck Institute for Astronomy), a team of scientists has proposed an idea that might help solve this puzzle. If the Ophiuchus stellar stream is on a chaotic orbit common in triaxial potentials, which the Milky Ways may be then the stream ends can fan out, with stars spreading in position and velocity.The fanned part of the stream, however, would be difficult to detect because of its low surface brightness. As a result, the Ophiuchus stellar stream could actually be longer than originally measured, implying that it was disrupted longer ago than was believed.Search for Fan StarsTo test this idea, Sesar and collaborators performed a search around the ends of the stream, looking for stars thatare of the right type to match the stream,are at the predicted distance of the stream,are located near the stream ends, andhave velocities that match the stream and dont match the background halo stars.Histogram of the heliocentric velocities of the 43 target stars. Six stars have velocities matching the stream velocity. Two of these are located in the main stream; the other

  10. Molecular Electronics for Frequency Domain Optical Storage. Persistent Spectral Hole-Burning. A Review.

    DTIC Science & Technology

    1985-03-25

    if applicable) Office of Naval Research IBM Almaden Research Center Chemistry Division, Code 1113 6c. ADDRESS (City, State, and ZIP Code) 7b...NOTATION Journal of Molecular Electronics 17. .* COSATI CODES 18. SUBJECT TERMS (Continue on reverse of necessary and identify by block number) FIEL GRUP SB...GOUP Molecular electronics, spectral hole-burning, frequency I I domain. optical storage, solid state photo chemistry , * I photon gating. 19. ABSTRACT

  11. Two-Photon Optical Storage in Photorefractive Polymers in the Near-Infrared Spectral Range

    NASA Astrophysics Data System (ADS)

    Day, Daniel; Gu, Min; Smallridge, Andrew

    We report the use of a polymer-based photorefractive material for three-dimensional bit optical data storage using near-infrared illumination. The research was conducted using photorefractive materials that were fabricated in two polymer matrices: poly(N-vinylcarbazole) (PVK) and poly(Methyl Methacrylate) (PMMA). The recording samples also consisted of the following compounds in various proportions: 2,5-dimethyl-4-(p-nitrophenylazo)anisole (DMNPAA), 2,4,7-trinitro-9-fluorenone (TNF) and N-ethylcarbazole (ECZ). Two-photon excitation was used as the recording mechanism to achieve rewritable bit data storage in a photorefractive polymer. As a result of two-photon excitation, the quadratic dependence of the excitation on the incident intensity produces an excitation volume that is confined to the focal region in both the transverse and axial directions. The use of ultrashort pulsed lasers, while effective, is not a practical solution for an optical data storage system. This research demonstrates the ability to produce three-dimensional rewritable bit data storage using continuous-wave illumination. Using this technology it has been possible to achieve a density of 88 Gbits/cm3, which in the future could be increased to 3.5 Tbits/cm3.

  12. [The Parkinson puzzle].

    PubMed

    Guseo, András

    2012-12-30

    Parkinson's disease is one of the most frequent progressive degenerative disorders with unknown origin of the nervous system. The commutation of the disease on Guam led to the discovery of a neurotoxin which was also found in other continents. This neurotoxin was identified in the common cyanobacteria (blue-green algae). Early clinical observations suggested some loose correlations with gastric and duodenal ulcer and Parkinson's disease, while recent studies revealed a toxin, almost identical to that found in cyanobacteria in one strain of Helicobacter pylori, which proved to cause Parkinson like symptoms in animals. Therefore, it cannot be ruled out that there is a slowly progressive poisoning in Parkinson's disease. The disease specific alpha-sinuclein inclusions can be found in nerve cells of the intestinal mucosa far before the appearance of clinical symptoms indicating that the disease may start in the intestines. These results are strengthened by the results of Borody's fecal transplants, after which in Parkinson patients showed a symptomatic improvement. Based on these observations the Parkinson puzzle is getting complete. Although these observations are not evidence based, they may indicate a new way for basic clinical research, as well as a new way of thinking for clinicians. These new observations in psycho-neuro-immunology strengthen the fact that immunological factors may also play a critical factor facilitating local cell necrosis which may be influenced easily.

  13. The birth order puzzle.

    PubMed

    Zajonc, R B; Markus, H; Markus, G B

    1979-08-01

    Studies relating intellectual performance to birth order report conflicting results, some finding intellectual scores to increase, others to decrease with birth order. In contrast, the relationship between intellectual performance and family size is stable and consistently replicable. Why do these two highly related variables generate such divergent results? This birth order puzzle is resolved by means of the confluence model that quantifies the influences upon intellectual growth arising within the family context. At the time of a new birth, two opposing influences act upon intellectual growth of the elder sibling: (a) his or her intellectual environment is "diluted" and (b) he or she loses the "last-born's handicap" and begins serving as an intellectual resource to the younger sibling. Since these opposite effects are not equal in magnitude, the differences in intellectual performance among birth ranks are shown to be age dependent. While elder children may surpass their younger siblings in intellectual performance at some ages, they may be overtaken by them at others. Thus when age is taken into consideration, the birth order literature loses its chaotic character and an orderly pattern of results emerges.

  14. Controllable all-optical stochastic logic gates and their delay storages based on the cascaded VCSELs with optical-injection

    NASA Astrophysics Data System (ADS)

    Zhong, Dongzhou; Luo, Wei; Xu, Geliang

    2016-09-01

    Using the dynamical properties of the polarization bistability that depends on the detuning of the injected light, we propose a novel approach to implement reliable all-optical stochastic logic gates in the cascaded vertical cavity surface emitting lasers (VCSELs) with optical-injection. Here, two logic inputs are encoded in the detuning of the injected light from a tunable CW laser. The logic outputs are decoded from the two orthogonal polarization lights emitted from the optically injected VCSELs. For the same logic inputs, under electro-optic modulation, we perform various digital signal processing (NOT, AND, NAND, XOR, XNOR, OR, NOR) in the all-optical domain by controlling the logic operation of the applied electric field. Also we explore their delay storages by using the mechanism of the generalized chaotic synchronization. To quantify the reliabilities of these logic gates, we further demonstrate their success probabilities. Project supported by the National Natural Science Foundation of China (Grant No. 61475120) and the Innovative Projects in Guangdong Colleges and Universities, China (Grant Nos. 2014KTSCX134 and 2015KTSCX146).

  15. Nonlinear Optical Properties of Bacteriorhodopsin and Retinal Chromophores and Their Applications for Optical Information Storage and Processing.

    NASA Astrophysics Data System (ADS)

    Chen, Zhongping

    Retinal, a conjugated polyene, plays a crucial role in biology. Both the visual pigments and the energy transducing protein, bacteriorhodopsin (BR) have a form of retinal as their chromophores. Because visual excitation and energy transduction in these systems is initiated by the promotion of retinal to an excited electronic state, information about the excited-state structure of retinal and the effect of chromophore/protein interactions on this structure are essential to understanding the functions of these systems. In this thesis, surface second harmonic (SH) generation is used to measure the light-induced dipole moment changes of a series of retinal derivatives that were designed and synthesized to model specific components of chromophore/protein interactions. In addition, we report an in situ probe of the dipole moment change of the retinal chromophore bound in BR by SH generation from oriented purple membranes. The dipole moment changes of various forms of BR, including light-adapted, dark-adapted, blue, and acid purple membrane, were measured and compared. These results, combined with the results from model compounds, elucidate the effects of the chromophore/protein interactions on light-induced charge redistribution and give insight on the fundamental nature of light excitation and energy storage in SR and rhodopsin. Furthermore, the dependence of the molecular hyperpolarizability of the conjugated molecules on donor/acceptor strength, protonation, conjugate length, planarity, and nonconjugate charges is investigated. Our study shows for the first time that nonconjugated charges have a very large effect on the nonlinear optical properties of conjugated molecules. BR has interesting photochromic characteristics, very large optical nonlinearities, and a unique optoelectrical property where the polarity of the photovoltage depends on both its photochromic state and the excitation wavelength. These unique characteristics coupled with its high stability make BR

  16. Ultra-high density optical data storage in common transparent plastics

    PubMed Central

    Kallepalli, Deepak L. N.; Alshehri, Ali M.; Marquez, Daniela T.; Andrzejewski, Lukasz; Scaiano, Juan C.; Bhardwaj, Ravi

    2016-01-01

    The ever-increasing demand for high data storage capacity has spurred research on development of innovative technologies and new storage materials. Conventional GByte optical discs (DVDs and Bluray) can be transformed into ultrahigh capacity storage media by encoding multi-level and multiplexed information within the three dimensional volume of a recording medium. However, in most cases the recording medium had to be photosensitive requiring doping with photochromic molecules or nanoparticles in a multilayer stack or in the bulk material. Here, we show high-density data storage in commonly available plastics without any special material preparation. A pulsed laser was used to record data in micron-sized modified regions. Upon excitation by the read laser, each modified region emits fluorescence whose intensity represents 32 grey levels corresponding to 5 bits. We demonstrate up to 20 layers of embedded data. Adjusting the read laser power and detector sensitivity storage capacities up to 0.2 TBytes can be achieved in a standard 120 mm disc. PMID:27221758

  17. Ultra-high density optical data storage in common transparent plastics

    NASA Astrophysics Data System (ADS)

    Kallepalli, Deepak L. N.; Alshehri, Ali M.; Marquez, Daniela T.; Andrzejewski, Lukasz; Scaiano, Juan C.; Bhardwaj, Ravi

    2016-05-01

    The ever-increasing demand for high data storage capacity has spurred research on development of innovative technologies and new storage materials. Conventional GByte optical discs (DVDs and Bluray) can be transformed into ultrahigh capacity storage media by encoding multi-level and multiplexed information within the three dimensional volume of a recording medium. However, in most cases the recording medium had to be photosensitive requiring doping with photochromic molecules or nanoparticles in a multilayer stack or in the bulk material. Here, we show high-density data storage in commonly available plastics without any special material preparation. A pulsed laser was used to record data in micron-sized modified regions. Upon excitation by the read laser, each modified region emits fluorescence whose intensity represents 32 grey levels corresponding to 5 bits. We demonstrate up to 20 layers of embedded data. Adjusting the read laser power and detector sensitivity storage capacities up to 0.2 TBytes can be achieved in a standard 120 mm disc.

  18. Ultra-high density optical data storage in common transparent plastics.

    PubMed

    Kallepalli, Deepak L N; Alshehri, Ali M; Marquez, Daniela T; Andrzejewski, Lukasz; Scaiano, Juan C; Bhardwaj, Ravi

    2016-05-25

    The ever-increasing demand for high data storage capacity has spurred research on development of innovative technologies and new storage materials. Conventional GByte optical discs (DVDs and Bluray) can be transformed into ultrahigh capacity storage media by encoding multi-level and multiplexed information within the three dimensional volume of a recording medium. However, in most cases the recording medium had to be photosensitive requiring doping with photochromic molecules or nanoparticles in a multilayer stack or in the bulk material. Here, we show high-density data storage in commonly available plastics without any special material preparation. A pulsed laser was used to record data in micron-sized modified regions. Upon excitation by the read laser, each modified region emits fluorescence whose intensity represents 32 grey levels corresponding to 5 bits. We demonstrate up to 20 layers of embedded data. Adjusting the read laser power and detector sensitivity storage capacities up to 0.2 TBytes can be achieved in a standard 120 mm disc.

  19. Conversion of Hard-Copy Documents to Digital Format Utilizing Optical Scanners and Optical Storage Media

    DTIC Science & Technology

    1989-03-01

    algorithms, known as Modified Huffman (MH) and Modified Read (MR) encoding. ( Matlin , 1988, p. 75) 1. Modified Huffman Encoding Also known as one...Thesis, Naval Postgraduate School, Monterey, California, June 1987. Matlin , Mark, "Image Compression for Document Storage," ESD: The Electronic System

  20. LIGHT SOURCE: Optics for the lattice of the compact storage ring for a Compton X-ray source

    NASA Astrophysics Data System (ADS)

    Yu, Pei-Cheng; Wang, Yu; Shen, Xiao-Zhe; Huang, Wen-Hui; Yan, Li-Xin; Du, Ying-Chao; Li, Ren-Kai; Tang, Chuan-Xiang

    2009-06-01

    We present two types of optics for the lattice of a compact storage ring for a Compton X-ray source. The optics design for different operation modes of the storage ring are discussed in detail. For the pulse mode optics, an IBS-suppression scheme is applied to optimize the optics for lower IBS emittance growth rate; as for the steady mode, the method to control momentum compact factor is adopted [Gladkikh P, Phys. Rev. ST Accel. Beams 8, 050702] to obtain stability of the electron beam.

  1. Waveguide optical scanner with increased deflection sensitivity for optical data storage

    NASA Astrophysics Data System (ADS)

    Chen, Qibao; Chiu, Yi; Devasahayam, Adrian J.; Seigler, Michael A.; Lambeth, David N.; Schlesinger, Tuviah E.; Stancil, Daniel D.

    1994-10-01

    Waveguide electrooptic (EO) beam scanners are of interest for applications requiring high speed, high throughput, low power consumption, and modest deflection. Such devices can be used in high performance optical recording and laser printer heads. We are pursuing a novel waveguide device structure in which prisms are formed by ferroelectric domain inversion in a substrate containing a planar waveguide. The device uses TM optical modes in z-cut substrates and is therefore compatible with waveguides used for high-efficiency optical second harmonic generation (SHG).

  2. Ultrathin reduced graphene oxide films for high performance optical data storage

    NASA Astrophysics Data System (ADS)

    Xing, Fei; Yang, Yong; Zhu, Siwei; Yuan, Xiaocong

    2015-10-01

    Optical data storage (ODS) represents revolutionary progress for the field of information storage capacity. When the thickness of data recording layer is similar to a few nanometer even atomic scale, the data point dimension can decrease to the minimum with stable mechanical property. Thus the new generation of ODS requires data recording layer in nanoscale to improve areal storage density, so that the more digital information can be stored in limited zone. Graphene, a novel two-dimensional (2D) material, is a type of monolayer laminated structure composed of carbon atoms and is currently the thinnest known material (the thickness of monolayer graphene is 3.35 Å). It is an ideal choice as a active layer for ODS media. Reduced graphene oxide, a graphene derivative, has outstanding polarization-dependent absorption characteristics under total internal reflection (TIR). The strong broadband absorption of reduced graphene oxide causes it to exhibit different reflectance for transverse electric (TE) and transverse magnetic (TM) modes under TIR, and the maximum reflectance ratio between TM and TE modes is close to 8 with 8 nm reduced graphene oxide films. It opens a door for a high signal to noise ratio (SNR) graphene-based optical data storage. Here, 8 nm high-temperature reduced graphene oxide (h-rGO) films was used for the ultrathin active layer of ODS. The data writing was performed on the h-rGO active layer based on photolithography technology. Under TIR, a balanced detection technology in the experiment converts the optical signals into electric signals and simultaneously amplifies them. The reading results show a stable SNR up to 500, and the graphene-based ODS medium has a high transparency performance.

  3. New optical architecture for holographic data storage system compatible with Blu-ray Disc™ system

    NASA Astrophysics Data System (ADS)

    Shimada, Ken-ichi; Ide, Tatsuro; Shimano, Takeshi; Anderson, Ken; Curtis, Kevin

    2014-02-01

    A new optical architecture for holographic data storage system which is compatible with a Blu-ray Disc™ (BD) system is proposed. In the architecture, both signal and reference beams pass through a single objective lens with numerical aperture (NA) 0.85 for realizing angularly multiplexed recording. The geometry of the architecture brings a high affinity with an optical architecture in the BD system because the objective lens can be placed parallel to a holographic medium. Through the comparison of experimental results with theory, the validity of the optical architecture was verified and demonstrated that the conventional objective lens motion technique in the BD system is available for angularly multiplexed recording. The test-bed composed of a blue laser system and an objective lens of the NA 0.85 was designed. The feasibility of its compatibility with BD is examined through the designed test-bed.

  4. Optical readout of hydrogen storage in films of Au and Pd

    NASA Astrophysics Data System (ADS)

    Nishijima, Yoshiaki; Shimizu, Shogo; Kurihara, Keisuke; Hashimoto, Yoshikazu; Takahashi, Hajime; Balčytis, Armandas; Seniutinas, Gediminas; Okazaki, Shinji; Juodkazytė, Jurga; Iwasa, Takeshi; Taketsugu, Tetsuya; Tominaga, Yoriko; Juodkazis, Saulius

    2017-10-01

    For hydrogen sensor and storage applications, films of Au and Pd were (i) co-sputtered at different rates or (ii) deposited in a sequential layer-by-layer fashion on a cover glass. Peculiarities of hydrogen uptake and release were optically monitored using 1.3 micrometers wavelength light. Increase of optical transmission was observed for hydrogenated Pd-rich films of 10-30 nm thickness. Up to a three times slower hydrogen release took place as compared with the hydrogen uptake. Composition ratio of Au:Pd and thermal treatment of films provided control over the optical extinction changes and hydrogen uptake/release time constants. Higher uptake and release rates were observed in the annealed Au:Pd films as compared to those deposited at room temperature and were faster for the Au-richer films. Three main parameters relevant for sensors: sensitivity, selectivity, stability (reproducibility) are discussed together with the hydrogenation mechanism in Au:Pd alloys.

  5. Squeezing red blood cells on an optical waveguide to monitor cell deformability during blood storage.

    PubMed

    Ahluwalia, Balpreet Singh; McCourt, Peter; Oteiza, Ana; Wilkinson, James S; Huser, Thomas R; Hellesø, Olav Gaute

    2015-01-07

    Red blood cells squeeze through micro-capillaries as part of blood circulation in the body. The deformability of red blood cells is thus critical for blood circulation. In this work, we report a method to optically squeeze red blood cells using the evanescent field present on top of a planar waveguide chip. The optical forces from a narrow waveguide are used to squeeze red blood cells to a size comparable to the waveguide width. Optical forces and pressure distributions on the cells are numerically computed to explain the squeezing process. The proposed technique is used to quantify the loss of blood deformability that occurs during blood storage lesion. Squeezing red blood cells using waveguides is a sensitive technique and works simultaneously on several cells, making the method suitable for monitoring stored blood.

  6. From the surface to volume: concepts for the next generation of optical-holographic data-storage materials.

    PubMed

    Bruder, Friedrich-Karl; Hagen, Rainer; Rölle, Thomas; Weiser, Marc-Stephan; Fäcke, Thomas

    2011-05-09

    Optical data storage has had a major impact on daily life since its introduction to the market in 1982. Compact discs (CDs), digital versatile discs (DVDs), and Blu-ray discs (BDs) are universal data-storage formats with the advantage that the reading and writing of the digital data does not require contact and is therefore wear-free. These formats allow convenient and fast data access, high transfer rates, and electricity-free data storage with low overall archiving costs. The driving force for development in this area is the constant need for increased data-storage capacity and transfer rate. The use of holographic principles for optical data storage is an elegant way to increase the storage capacity and the transfer rate, because by this technique the data can be stored in the volume of the storage material and, moreover, it can be optically processed in parallel. This Review describes the fundamental requirements for holographic data-storage materials and compares the general concepts for the materials used. An overview of the performance of current read-write devices shows how far holographic data storage has already been developed.

  7. Acousto-optic parallel read/write head for optical disk data storage.

    PubMed

    McLeod, Robert R; Walter, Sarah K

    2006-09-20

    Parallel read and write of optical disks has traditionally used a static grating for read or a linear array of independent lasers for read and write. Depending on the implementation, these systems suffer from coherent cross talk, excessive space between spots, and an inability to independently track. We show that a dynamic acousto-optic grating can generate multiple parallel read/write spots on the disk, each of which can be independently modulated and tracked and all of which are incoherent in less that a bit period. The resulting disk pickup can potentially reach gigabit per second transfer rates with only a modest increase in the drive complexity.

  8. Acousto-optic parallel read/write head for optical disk data storage

    NASA Astrophysics Data System (ADS)

    McLeod, Robert R.; Walter, Sarah K.

    2006-09-01

    Parallel read and write of optical disks has traditionally used a static grating for read or a linear array of independent lasers for read and write. Depending on the implementation, these systems suffer from coherent cross talk, excessive space between spots, and an inability to independently track. We show that a dynamic acousto-optic grating can generate multiple parallel read/write spots on the disk, each of which can be independently modulated and tracked and all of which are incoherent in less that a bit period. The resulting disk pickup can potentially reach gigabit per second transfer rates with only a modest increase in the drive complexity.

  9. Development of photorefractive polymers for real-time optical information storage

    NASA Astrophysics Data System (ADS)

    Mangaiyarkarasi, D.; Palanisamy, P. K.; Kannan, P.

    1999-03-01

    A large number of strong nonlinear optical and electro optical molecules and crystals are identified recently. With the discovery of the photorefractive (PR) effect and early realization of its potential utility, PR materials are of considerable interest for the development of all optical devices, such as high density optical data storage and image processing techniques. Organic materials are known to show strong electro optic effects. In organic materials, the properties required for the PR effect including photosensitivity, photoconductivity and electro optic response are provided by different molecules. As a result, the properties can be optimized separately, unlike in inorganic PR crystals such as LiNbO3. This paper describes the utilization of third order non-linearity induced in Xanthene dye doped gelatin and poly (eosin acrylate) & poly (eosin acrylate-co-isobutyl acrylate) films resulting in direct storage without the need for any further processing i.e., no wet chemical or post thermal/photochemical processing are required. With required amount of solvent and monomer in the presence of benzoyl peroxide (initiator), polymerization reaction was carried out under nitrogen atmosphere. Polymer samples were characterized by NMR, IR, FT-IR & TGA. The polymers were soluble in THF, DMSO, DMF & DMAC solvents and form good optical quality films by spin as well as dip coating. Polymer thin films were prepared with different concentrations of polymer solution onto the glass slides. The UV-visible absorption spectra of the spin coated polymer films showed a maximum at 538 nm. In our simplest optical system, Q- switched, second harmonic Nd-YAG laser light at wavelength 532 nm was used for recording. Two beams split from the same laser were made to superpose with path difference less than the coherent length. One of the beam acted as information carrying beam while the other acted as reference beam. In this present study, we report the direction formation of surface

  10. New composite blue sensitive materials for high resolution optical data storage

    NASA Astrophysics Data System (ADS)

    Criante, L.; Castagna, R.; Vita, F.; Lucchetta, D. E.; Simoni, F.; Frohmann, S.; Feid, T.; Orlic, S.

    2007-09-01

    In the last three decades several kinds of organic mixtures for holographic recording were developed in order to achieve a new class of DVD-like optical memories for high-density optical data storage. The holographic materials should satisfy the following requirements: high sensitivity to blue light, low losses, high spatial resolution and long term stability. To this aim we developed new organic photosensitive mixtures based on only three components. We recorded high spatial frequency reflection gratings up to 7400 lines/mm with blue laser light (405 nm) by using a conventional holographic setup. We obtained a macro grating diffraction efficiency up to 67%, refractive index modulation over 0.01, optical shrinkage < 2 % and overall losses ~5%. In order to characterize data-storage materials independently on the experimental conditions, the sensitivity has been evaluated through the S parameter which takes into account the diffraction efficiency, recording light intensity, exposure time and sample thickness. The amazing obtained values of S >10 5 cm/J evidences a very fast recording process with a very low writing intensity (less than 20 mW/cm2) corresponding to a recording energy density of few mJ/cm2. The performance of these materials have been also tested in the microholographic geometry.

  11. Inspection of commercial optical devices for data storage using a three Gaussian beam microscope interferometer

    SciTech Connect

    Flores, J. Mauricio; Cywiak, Moises; Servin, Manuel; Juarez P, Lorenzo

    2008-09-20

    Recently, an interferometric profilometer based on the heterodyning of three Gaussian beams has been reported. This microscope interferometer, called a three Gaussian beam interferometer, has been used to profile high quality optical surfaces that exhibit constant reflectivity with high vertical resolution and lateral resolution near {lambda}. We report the use of this interferometer to measure the profiles of two commercially available optical surfaces for data storage, namely, the compact disk (CD-R) and the digital versatile disk (DVD-R). We include experimental results from a one-dimensional radial scan of these devices without data marks. The measurements are taken by placing the devices with the polycarbonate surface facing the probe beam of the interferometer. This microscope interferometer is unique when compared with other optical measuring instruments because it uses narrowband detection, filters out undesirable noisy signals, and because the amplitude of the output voltage signal is basically proportional to the local vertical height of the surface under test, thus detecting with high sensitivity. We show that the resulting profiles, measured with this interferometer across the polycarbonate layer, provide valuable information about the track profiles, making this interferometer a suitable tool for quality control of surface storage devices.

  12. Inspection of commercial optical devices for data storage using a three Gaussian beam microscope interferometer.

    PubMed

    Flores, J Mauricio; Cywiak, Moisés; Servín, Manuel; Juárez, Lorenzo

    2008-09-20

    Recently, an interferometric profilometer based on the heterodyning of three Gaussian beams has been reported. This microscope interferometer, called a three Gaussian beam interferometer, has been used to profile high quality optical surfaces that exhibit constant reflectivity with high vertical resolution and lateral resolution near lambda. We report the use of this interferometer to measure the profiles of two commercially available optical surfaces for data storage, namely, the compact disk (CD-R) and the digital versatile disk (DVD-R). We include experimental results from a one-dimensional radial scan of these devices without data marks. The measurements are taken by placing the devices with the polycarbonate surface facing the probe beam of the interferometer. This microscope interferometer is unique when compared with other optical measuring instruments because it uses narrowband detection, filters out undesirable noisy signals, and because the amplitude of the output voltage signal is basically proportional to the local vertical height of the surface under test, thus detecting with high sensitivity. We show that the resulting profiles, measured with this interferometer across the polycarbonate layer, provide valuable information about the track profiles, making this interferometer a suitable tool for quality control of surface storage devices.

  13. Ferro-/Ferri-Exchange Coupled Magnetic Double Layers For High Density Magneto-optical Data Storage

    NASA Astrophysics Data System (ADS)

    Wang, Xian-Ying; Wang, Jing; Yang, Jun-He

    2009-10-01

    PtCo/TbFeCo ferro-/ferri-exchange coupled double layer film (ECDL) was fabricated for high density magneto-optical (MO) data storage. At room temperature (RT), the PtCo film is in-plane magnetized and acts as a mask layer. However, at elevated temperature, it turns to be out-of-plane magnetized because of the strong exchange coupling interactions with the TbFeCo layer. Therefore, this ECDL film has a magnetically induced superresolution (MSR) effect. Combining it with the good Kerr signal at short wavelength, the PtCo/TbFeCo film can be a good candidate for blue laser-MSR MO data storage.

  14. Low-cost medical image storage and manipulation using optical disk subsystems

    NASA Astrophysics Data System (ADS)

    Glenn, William V., Jr.; Marx, Peter S.

    1990-08-01

    Traditionally, medical imaging has required large capital investments into workstations and storage subsystems. Many vendors have chosen to offer proprietary systems which are expensive to develop and costly to the institutions which purchase them. Our experience has been that this is unnecessary; most traditional imaging functions in the digital modalities of computed tomography (CT) and magnetic resonance imaging (MM) can be performed using off-the-shelf hardware with relatisely inexpensive software. In order to reduce the cost of medical imaging, our approach has been to choose computers and storage subsystems that are efficient, inexpensive, and easy-to-use (after all, the users are interested in practicing medicine, not computer science.) With these goals in mind, we chose to use a general purpose computer (the Apple Macintosh Ilci) with two types of high-capacity optical storage devices (both magneto-optical and write once, read multiple (WORM) disc subsystems.) We have developed a powerful, yet user-friendly medical imaging workstation oriented towards radiologists, orthopadic surgeons, neurosurgeons, and other users of medical images. In addition to providing inexpensive storage, the workstation is capable of multiplanar reformatting (MPR), 3D MM angiography, and other image processing functions. The resulting images may be annotated, windowed, and filmed on to 14x17" radiology film for presentation to the referring physicians and their patients. This system can be considered to be a picture archiving and communication system (PACS) for private physicians and small clinics; further, it is small enough for desktop environments and inexpensive enough for clinicians to purchase.

  15. The puzzling case of the accreting millisecond X-ray pulsar IGR J00291+5934: flaring optical emission during quiescence

    NASA Astrophysics Data System (ADS)

    Baglio, M. C.; Campana, S.; D'Avanzo, P.; Papitto, A.; Burderi, L.; Di Salvo, T.; Muñoz-Darias, T.; Rea, N.; Torres, D. F.

    2017-04-01

    We present an optical (gri) study during quiescence of the accreting millisecond X-ray pulsar IGR J00291+5934 performed with the 10.4 m Gran Telescopio Canarias (GTC) in August 2014. Although the source was in quiescence at the time of our observations, it showed a strong optical flaring activity, more pronounced in bluer filters (i.e. the g-band). After subtracting the flares, we tentatively recovered a sinusoidal modulation at the system orbital period in all bands, even when a significant phase shift with respect to an irradiated star, typical of accreting millisecond X-ray pulsars, was detected. We conclude that the observed flaring could be a manifestation of the presence of an accretion disc in the system. The observed light curve variability could be explained by the presence of a superhump, which might be another proof of the formation of an accretion disc. In particular, the disc at the time of our observations was probably preparing the new outburst of the source, which occurred a few months later, in 2015. Based on observations made with the Gran Telescopio Canarias (GTC), installed in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias, in the island of La Palma.

  16. Optical memory development. Volume 2: Gain-assisted holographic storage media

    NASA Technical Reports Server (NTRS)

    Gange, R. A.; Mezrich, R. S.

    1972-01-01

    Thin deformable films were investigated for use as the storage medium in a holographic optical memory. The research was directed toward solving the problems of material fatigue, selective heat addressing, electrical charging of the film surface and charge patterning by light. A number of solutions to these problems were found but the main conclusion to be drawn from the work is that deformable media which employ heat in the recording process are not satisfactory for use in a high-speed random-access read/write holographic memory. They are, however, a viable approach in applications where either high speed or random-access is not required.

  17. Chemistry of Art and Color Sudoku Puzzles

    ERIC Educational Resources Information Center

    Welsh, Michael J.

    2007-01-01

    Sudoku puzzle format was used to teach light science and chemistry terms to students of Chemistry of Art and Color. The puzzles were used to motivate and encourage students to learn chemistry in an easier and in friendly fashion.

  18. Chemistry of Art and Color Sudoku Puzzles

    ERIC Educational Resources Information Center

    Welsh, Michael J.

    2007-01-01

    Sudoku puzzle format was used to teach light science and chemistry terms to students of Chemistry of Art and Color. The puzzles were used to motivate and encourage students to learn chemistry in an easier and in friendly fashion.

  19. Rapid production of structural color images with optical data storage capabilities

    NASA Astrophysics Data System (ADS)

    Rezaei, Mohamad; Jiang, Hao; Qarehbaghi, Reza; Naghshineh, Mohammad; Kaminska, Bozena

    2015-03-01

    In this paper, we present novel methods to produce structural color image for any given color picture using a pixelated generic stamp named nanosubstrate. The nanosubstrate is composed of prefabricated arrays of red, green and blue subpixels. Each subpixel has nano-gratings and/or sub-wavelength structures which give structural colors through light diffraction. Micro-patterning techniques were implemented to produce the color images from the nanosubstrate by selective activation of subpixels. The nano-grating structures can be nanohole arrays, which after replication are converted to nanopillar arrays or vice versa. It has been demonstrated that visible and invisible data can be easily stored using these fabrication methods and the information can be easily read. Therefore the techniques can be employed to produce personalized and customized color images for applications in optical document security and publicity, and can also be complemented by combined optical data storage capabilities.

  20. Achieve both multiwavelength and multilevel optical storage on compact disk by diarylethene

    NASA Astrophysics Data System (ADS)

    Liu, Xuedong; Pu, Shouzhi; Zhao, Fuqun; Qi, Guosheng; Zhang, Fushi

    2005-01-01

    The novel photochromism, diarylethene derivatives, 1,2-bis(2,5-dimethyl-thien-3-yl)perfluoro cyclopentene (1a) and 1,2-bis(2-methyl-5-carbonylphenyl)-thien-3-yl) perfluorocyclo pentene(2a) were synthesized. And the PC discs of these two diarylethenes were prepared by spin-coating and vacuum evaporating method. To some extent, the high density recording was carried out the multi-wavelength and multi-level optical storage system. On the PC disc, single-wavelength and eight-level recording was realized by 2a, and two laser beams of 532nm and 650nm were used in two-wavelength eight-level recording and readout simultaneously. The results show that the reflectivity differences between the recording region and unrecording region is greater than 50%. The creation is that the two-wavelength and four-step optical recording on the PC disc achieved first time.

  1. Artists Create Puzzles, Scientists Solve Them.

    PubMed

    Goldstein, Joseph L

    2017-09-21

    The Spanish artist Diego Velázquez created a puzzle-painting 360 years ago that to this day remains unsolved, but still mystifies and intrigues. Unlike artists who get their thrills by creating puzzles that stimulate the imagination, scientists get their kicks by solving puzzles that advance biomedical research. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Sudoku Puzzles as Chemistry Learning Tools

    ERIC Educational Resources Information Center

    Crute, Thomas D.; Myers, Stephanie A.

    2007-01-01

    A sudoku puzzle was designed that incorporated lists of chemistry terms like polyatomic ions, organic functional groups or strong nucleophiles that students need to learn. It was found that students enjoyed solving such puzzles and also such puzzles made the boring tasks of memorizing basic chemical terms an exciting one.

  3. Sudoku Puzzles as Chemistry Learning Tools

    ERIC Educational Resources Information Center

    Crute, Thomas D.; Myers, Stephanie A.

    2007-01-01

    A sudoku puzzle was designed that incorporated lists of chemistry terms like polyatomic ions, organic functional groups or strong nucleophiles that students need to learn. It was found that students enjoyed solving such puzzles and also such puzzles made the boring tasks of memorizing basic chemical terms an exciting one.

  4. Japanese Logic Puzzles and Proof

    ERIC Educational Resources Information Center

    Wanko, Jeffrey J.

    2009-01-01

    An understanding of proof does not start in a high school geometry course. Rather, attention to logical reasoning throughout a student's school experience can help the development of proof readiness. In the spirit of problem solving, the author has begun to use some Japanese logic puzzles other than sudoku to help students develop additional…

  5. Teaching Inductive Reasoning with Puzzles

    ERIC Educational Resources Information Center

    Wanko, Jeffrey J.

    2017-01-01

    Working with language-independent logic structures can help students develop both inductive and deductive reasoning skills. The Japanese publisher Nikoli (with resources available both in print and online) produces a treasure trove of language-independent logic puzzles. The Nikoli print resources are mostly in Japanese, creating the extra…

  6. On a Perplexing Polynomial Puzzle

    ERIC Educational Resources Information Center

    Richmond, Bettina

    2010-01-01

    It seems rather surprising that any given polynomial p(x) with nonnegative integer coefficients can be determined by just the two values p(1) and p(a), where a is any integer greater than p(1). This result has become known as the "perplexing polynomial puzzle." Here, we address the natural question of what might be required to determine a…

  7. Canadian Open Tennis. Puzzle Corner.

    ERIC Educational Resources Information Center

    Andrews, Ian A.

    2000-01-01

    Describes the du Maurier Open, a women's tennis tournament. Explains that tennis becomes an elite sport at the level of the du Maurier Open. Presents a crossword puzzle that focuses on many of the female tennis stars and provides the across and down clues, a word list, and the answer key. (CMK)

  8. Surface-micromachined optical polarizers for magneto-optical data storage

    NASA Astrophysics Data System (ADS)

    Pu, Chuan; Zhu, Zuhua; Lo, Yu-Hwa

    1998-07-01

    Polarizers and polarization beam splitters are the most important devices in magneto-optical readout system. With a commercially available foundry polysilicon surface micromachining process (Multi-User Means ProcesS, or MUMPS) offered by MCNC (Mems Center at North Carolina), we have realized, on a single Si chip, an integrated polarization beam splitting system with a binary phase Fresnel lens for collimation. Polarization extinction ratios of 10 dB for the transmitted light and over 20 dB for the reflected light have been achieved. The whole system is prealigned using Computer-Aided Design on a Si substrate and is then lifted up perpendicular to the substrate after structure release.

  9. Optical-NIR spectroscopy of the puzzling γ-ray source 3FGL 1603.9-4903/PMN J1603-4904 with X-Shooter

    NASA Astrophysics Data System (ADS)

    Goldoni, P.; Pita, S.; Boisson, C.; Müller, C.; Dauser, T.; Jung, I.; Krauß, F.; Lenain, J.-P.; Sol, H.

    2016-02-01

    Context. The Fermi/LAT instrument has detected about two thousand extragalactic high energy (E ≥ 100 MeV) γ-ray sources. One of the brightest is 3FGL J1603.9-4903; it is associated to the radio source PMN J1603-4904. Its nature is not yet clear, it could be either a very peculiar BL Lac or a compact symmetric object radio source which are considered as the early stage of a radio galaxy. The latter, if confirmed, would be the first detection in γ-rays for this class of objects. A redshift z = 0.18 ± 0.01 has recently been claimed on the basis of the detection of a single X-ray line at 5.44 ± 0.05 keV which has been interpreted as a 6.4 keV (rest frame) fluorescent line. Aims: We aim to investigate the nature of 3FGL J1603.9-4903/PMN J1603-4904 using optical-to near-IR (NIR) spectroscopy. Methods: We observed PMN J1603-4904 with the UV-NIR VLT/X-Shooter spectrograph for two hours. We extracted spectra in the visible and NIR range that we calibrated in flux and corrected for telluric absorption. We systematically searched for absorption and emission features. Results: The source was detected starting from ~6300 Å down to 24 000 Å with an intensity similar to that of its 2MASS counterpart and a mostly featureless spectrum. The continuum lacks absorption features and thus is non-stellar in origin and most likely non-thermal. In addition to this spectrum, we detected three emission lines that we interpret as the Hα-[NII] complex, the [SII]λ,λ6716, 6731 doublet and the [SIII]λ 9530 line; we obtain a redshift estimate of z = 0.2321 ± 0.0004. The line ratios suggest that a LINER/Seyfert nucleus powers the emission. This new redshift measurement implies that the X-ray line previously detected should be interpreted as a 6.7 keV line which is very peculiar. Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere, Chile, under program 095.B-0400(A). The raw FITS data files are available in the ESO archive.

  10. Real time monitoring of water level and temperature in storage fuel pools through optical fibre sensors.

    PubMed

    Rizzolo, S; Périsse, J; Boukenter, A; Ouerdane, Y; Marin, E; Macé, J-R; Cannas, M; Girard, S

    2017-08-18

    We present an innovative architecture of a Rayleigh-based optical fibre sensor for the monitoring of water level and temperature inside storage nuclear fuel pools. This sensor, able to withstand the harsh constraints encountered under accidental conditions such as those pointed-out during the Fukushima-Daiichi event (temperature up to 100 °C and radiation dose level up to ~20 kGy), exploits the Optical Frequency Domain Reflectometry technique to remotely monitor a radiation resistant silica-based optical fibre i.e. its sensing probe. We validate the efficiency and the robustness of water level measurements, which are extrapolated from the temperature profile along the fibre length, in a dedicated test bench allowing the simulation of the environmental operating and accidental conditions. The conceived prototype ensures an easy, practical and no invasive integration into existing nuclear facilities. The obtained results represent a significant breakthrough and comfort the ability of the developed system to overcome both operating and accidental constraints providing the distributed profiles of the water level (0-to-5 m) and temperature (20-to-100 °C) with a resolution that in accidental condition is better than 3 cm and of ~0.5 °C respectively. These new sensors will be able, as safeguards, to contribute and reinforce the safety in existing and future nuclear power plants.

  11. Acoustic emission detection with fiber optical sensors for dry cask storage health monitoring

    NASA Astrophysics Data System (ADS)

    Lin, Bin; Bao, Jingjing; Yu, Lingyu; Giurgiutiu, Victor

    2016-04-01

    The increasing number, size, and complexity of nuclear facilities deployed worldwide are increasing the need to maintain readiness and develop innovative sensing materials to monitor important to safety structures (ITS). In the past two decades, an extensive sensor technology development has been used for structural health monitoring (SHM). Technologies for the diagnosis and prognosis of a nuclear system, such as dry cask storage system (DCSS), can improve verification of the health of the structure that can eventually reduce the likelihood of inadvertently failure of a component. Fiber optical sensors have emerged as one of the major SHM technologies developed particularly for temperature and strain measurements. This paper presents the development of optical equipment that is suitable for ultrasonic guided wave detection for active SHM in the MHz range. An experimental study of using fiber Bragg grating (FBG) as acoustic emission (AE) sensors was performed on steel blocks. FBG have the advantage of being durable, lightweight, and easily embeddable into composite structures as well as being immune to electromagnetic interference and optically multiplexed. The temperature effect on the FBG sensors was also studied. A multi-channel FBG system was developed and compared with piezoelectric based AE system. The paper ends with conclusions and suggestions for further work.

  12. Monolayer optical memory cells based on artificial trap-mediated charge storage and release

    NASA Astrophysics Data System (ADS)

    Lee, Juwon; Pak, Sangyeon; Lee, Young-Woo; Cho, Yuljae; Hong, John; Giraud, Paul; Shin, Hyeon Suk; Morris, Stephen M.; Sohn, Jung Inn; Cha, Seungnam; Kim, Jong Min

    2017-03-01

    Monolayer transition metal dichalcogenides are considered to be promising candidates for flexible and transparent optoelectronics applications due to their direct bandgap and strong light-matter interactions. Although several monolayer-based photodetectors have been demonstrated, single-layered optical memory devices suitable for high-quality image sensing have received little attention. Here we report a concept for monolayer MoS2 optoelectronic memory devices using artificially-structured charge trap layers through the functionalization of the monolayer/dielectric interfaces, leading to localized electronic states that serve as a basis for electrically-induced charge trapping and optically-mediated charge release. Our devices exhibit excellent photo-responsive memory characteristics with a large linear dynamic range of ~4,700 (73.4 dB) coupled with a low OFF-state current (<4 pA), and a long storage lifetime of over 104 s. In addition, the multi-level detection of up to 8 optical states is successfully demonstrated. These results represent a significant step toward the development of future monolayer optoelectronic memory devices.

  13. Monolayer optical memory cells based on artificial trap-mediated charge storage and release.

    PubMed

    Lee, Juwon; Pak, Sangyeon; Lee, Young-Woo; Cho, Yuljae; Hong, John; Giraud, Paul; Shin, Hyeon Suk; Morris, Stephen M; Sohn, Jung Inn; Cha, SeungNam; Kim, Jong Min

    2017-03-24

    Monolayer transition metal dichalcogenides are considered to be promising candidates for flexible and transparent optoelectronics applications due to their direct bandgap and strong light-matter interactions. Although several monolayer-based photodetectors have been demonstrated, single-layered optical memory devices suitable for high-quality image sensing have received little attention. Here we report a concept for monolayer MoS2 optoelectronic memory devices using artificially-structured charge trap layers through the functionalization of the monolayer/dielectric interfaces, leading to localized electronic states that serve as a basis for electrically-induced charge trapping and optically-mediated charge release. Our devices exhibit excellent photo-responsive memory characteristics with a large linear dynamic range of ∼4,700 (73.4 dB) coupled with a low OFF-state current (<4 pA), and a long storage lifetime of over 10(4) s. In addition, the multi-level detection of up to 8 optical states is successfully demonstrated. These results represent a significant step toward the development of future monolayer optoelectronic memory devices.

  14. Construction-Paper Puzzle Masterpieces

    ERIC Educational Resources Information Center

    Vance, Shelly

    2010-01-01

    Creating an appreciation of art history in her junior-high students has always been one of the author's greatest challenges as an art teacher. In this article, the author describes how her eighth-grade students re-created a famous work of art--piece by piece, like a puzzle or a stained-glass window--out of construction paper. (Contains 1 resource.)

  15. Neutron star news and puzzles

    NASA Astrophysics Data System (ADS)

    Prakash, Madappa

    2014-08-01

    Gerry Brown has had the most influence on my career in Physics, and my life after graduate studies. This article gives a brief account of some of the many ways in which Gerry shaped my research. Focus is placed on the significant strides on neutron star research made by the group at Stony Brook, which Gerry built from scratch. Selected puzzles about neutron stars that remain to be solved are noted.

  16. Construction-Paper Puzzle Masterpieces

    ERIC Educational Resources Information Center

    Vance, Shelly

    2010-01-01

    Creating an appreciation of art history in her junior-high students has always been one of the author's greatest challenges as an art teacher. In this article, the author describes how her eighth-grade students re-created a famous work of art--piece by piece, like a puzzle or a stained-glass window--out of construction paper. (Contains 1 resource.)

  17. Preparation and optical properties of BaFCl:Eu 2+ X-ray storage phosphor

    NASA Astrophysics Data System (ADS)

    Secu, M.; Matei, L.; Serban, T.; Apostol, E.; Aldica, Gh; Silion, C.

    2000-11-01

    A new method for the preparation of BaFCl:Eu 2+ has been developed. A coprecipitation chemical reaction between BaCl 2 and NaF acidified aqueous solution has been used. Doping with Eu 2+ was carried out by adding EuF 3 during preparation time. A thermal treatment in vacuum similar to those used in the sintering process of supraconductive ceramics was used in order to accomplish the chemical reaction and to improve the homogeneity of europium ion distribution. Finally, a fine powder consisting of microcrystalline, 4-5 μm grains was obtained. The product has been checked by X-ray diffractometry and characterised by optical methods. Photoluminescence (PL) measurements attest the europium impurification and oxygen contamination during preparation, which has a great importance for the photostimulability properties of the compound. Photostimulated luminescence (PSL) of the X-irradiated samples shows good performance as X-ray storage phosphor.

  18. Systems Issues Pertaining to Holographic Optical Data Storage in Thick Bacteriorhodopsin Films

    NASA Technical Reports Server (NTRS)

    Downie, John D.; Timucin, Dogan A.; Gary, Charles K.; Oezcan, Meric; Smithey, Daniel T.; Crew, Marshall; Lau, Sonie (Technical Monitor)

    1998-01-01

    The optical data storage capacity and raw bit-error-rate achievable with thick photochromic bacteriorhodopsin (BR) films are investigated for sequential recording and read- out of angularly- and shift-multiplexed digital holograms inside a thick blue-membrane D85N BR film. We address the determination of an exposure schedule that produces equal diffraction efficiencies among each of the multiplexed holograms. This exposure schedule is determined by numerical simulations of the holographic recording process within the BR material, and maximizes the total grating strength. We also experimentally measure the shift selectivity and compare the results to theoretical predictions. Finally, we evaluate the bit-error-rate of a single hologram, and of multiple holograms stored within the film.

  19. Systems Issues Pertaining to Holographic Optical Data Storage in Thick Bacteriorhodopsin Films

    NASA Technical Reports Server (NTRS)

    Downie, John D.; Timucin, Dogan A.; Gary, Charles K.; Oezcan, Meric; Smithey, Daniel T.; Crew, Marshall; Lau, Sonie (Technical Monitor)

    1998-01-01

    The optical data storage capacity and raw bit-error-rate achievable with thick photochromic bacteriorhodopsin (BR) films are investigated for sequential recording and read- out of angularly- and shift-multiplexed digital holograms inside a thick blue-membrane D85N BR film. We address the determination of an exposure schedule that produces equal diffraction efficiencies among each of the multiplexed holograms. This exposure schedule is determined by numerical simulations of the holographic recording process within the BR material, and maximizes the total grating strength. We also experimentally measure the shift selectivity and compare the results to theoretical predictions. Finally, we evaluate the bit-error-rate of a single hologram, and of multiple holograms stored within the film.

  20. Ring-toric lens for focus-error sensing in optical data storage.

    PubMed

    Descour, M R; Simon, D I; Yeh, W H

    1999-03-10

    We discuss the design and performance of diffractive ring-toric lenses for focus-error sensing in optical data storage. A ring-toric lens images a point source of light to a ring-shaped image. Focus-error sensing is accomplished by means of monitoring the change in ring radius: The ring expands in response to a diverging wave front, and the ring contracts in response to a converging wave front. We describe the use of a segmented phi detector to generate a focus-error signal (FES). We found that the FES slope, a measure of sensitivity to disk defocus, is higher for the ring-toric lenses described in this paper than for other techniques such as the astigmatic and the obscuration methods. We measured an FES slope of 0.7 per micrometer of disk defocus (microm(-1)). The corresponding theoretical FES slope is 0.96 microm(-1).

  1. MeV ion-beam analysis of optical data storage films

    NASA Technical Reports Server (NTRS)

    Leavitt, J. A.; Mcintyre, L. C., Jr.; Lin, Z.

    1993-01-01

    Our objectives are threefold: (1) to accurately characterize optical data storage films by MeV ion-beam analysis (IBA) for ODSC collaborators; (2) to develop new and/or improved analysis techniques; and (3) to expand the capabilities of the IBA facility itself. Using H-1(+), He-4(+), and N-15(++) ion beams in the 1.5 MeV to 10 MeV energy range from a 5.5 MV Van de Graaff accelerator, film thickness (in atoms/sq cm), stoichiometry, impurity concentration profiles, and crystalline structure were determined by Rutherford backscattering (RBS), high-energy backscattering, channeling, nuclear reaction analysis (NRA) and proton induced X-ray emission (PIXE). Most of these techniques are discussed in detail in the ODSC Annual Report (February 17, 1987), p. 74. The PIXE technique is briefly discussed in the ODSC Annual Report (March 15, 1991), p. 23.

  2. Promising Rapid Access High-Capacity Mass Storage Technique For Diagnostic Information Utilizing Optical Disc

    NASA Astrophysics Data System (ADS)

    Colby, R. L.; Bartuska, A. J.; Herzog, D. G.

    1982-01-01

    The optical disc has become a new technique for mass digital data storage of X-ray images from examinations and films in todays hospitals. Up to 36,000 X-ray images can be stored on one side of a 12-inch disc by melting holes 0.015 mils in size in an ablative material such as tellerium with a laser beam. This unique characteristic makes the disc suitable for storage and retrieval of X-rays in a record and playback system in either a single disc or multiple disc "jukebox" configuration. Doctors, nurses, technicians and other hospital personnel can call up a particular X-ray in less than 0.6 of a second in an on-line single disc system and up to less than 6 seconds in an on-line "jukebox" system. The jukebox is configured to hold up to 100 discs, thus storing 3,600,000 X-rays in hospitals with a bed size of greater than 500. The estimated exposed films on file in those hospitals is 327,400,000 and the estimated annual X-ray exams are 44,300. Thus, a single disc system could be used for an all electronic X-ray scanning system for annual X-ray exams. The jukebox configuration, which has expansion capability for servicing multiple simultaneous user request, can be applied to large archival mass storage. These systems could store the existing exposed films in hospitals with bed size greater than 500 at record and playback data rates of 50 Mb/s with access times of less than 15 seconds.

  3. Solar optics-based active panel for solar energy storage and disinfection of greywater.

    PubMed

    Lee, W; Song, J; Son, J H; Gutierrez, M P; Kang, T; Kim, D; Lee, L P

    2016-09-01

    Smart city and innovative building strategies are becoming increasingly more necessary because advancing a sustainable building system is regarded as a promising solution to overcome the depleting water and energy. However, current sustainable building systems mainly focus on energy saving and miss a holistic integration of water regeneration and energy generation. Here, we present a theoretical study of a solar optics-based active panel (SOAP) that enables both solar energy storage and photothermal disinfection of greywater simultaneously. Solar collector efficiency of energy storage and disinfection rate of greywater have been investigated. Due to the light focusing by microlens, the solar collector efficiency is enhanced from 25% to 65%, compared to that without the microlens. The simulation of greywater sterilization shows that 100% disinfection can be accomplished by our SOAP for different types of bacteria including Escherichia coli. Numerical simulation reveals that our SOAP as a lab-on-a-wall system can resolve the water and energy problem in future sustainable building systems.

  4. Threshold response using modulated continuous wave illumination for multilayer 3D optical data storage

    NASA Astrophysics Data System (ADS)

    Saini, A.; Christenson, C. W.; Khattab, T. A.; Wang, R.; Twieg, R. J.; Singer, K. D.

    2017-01-01

    In order to achieve a high capacity 3D optical data storage medium, a nonlinear or threshold writing process is necessary to localize data in the axial dimension. To this end, commercial multilayer discs use thermal ablation of metal films or phase change materials to realize such a threshold process. This paper addresses a threshold writing mechanism relevant to recently reported fluorescence-based data storage in dye-doped co-extruded multilayer films. To gain understanding of the essential physics, single layer spun coat films were used so that the data is easily accessible by analytical techniques. Data were written by attenuating the fluorescence using nanosecond-range exposure times from a 488 nm continuous wave laser overlapping with the single photon absorption spectrum. The threshold writing process was studied over a range of exposure times and intensities, and with different fluorescent dyes. It was found that all of the dyes have a common temperature threshold where fluorescence begins to attenuate, and the physical nature of the thermal process was investigated.

  5. Optical data storage system with a planoellipsoidal solid immersion mirror illuminated directly by a point light source.

    PubMed

    Zhang, Yaoju

    2006-12-01

    A new solid immersion mirror called the planoellipsoidal (PE) solid immersion mirror (SIM) for the near-field optical storage is proposed and developed. The PE SIM has a small aperture on the apex of the ellipsoidal surface. The intensity distribution of the transmitted field is calculated by using the vector diffraction theory. Compared with a conventional solid immersion lens (SIL), the proposed PE SIM has the following features. A PE SIM replaces three optical elements of the collimator, objective, and SIL in a conventional SIL optical storage system, so that the optical system equipped with the PE SIM is not only simple in its assembly but is also effective in making an optical head unit. The PE SIM obtains light from a point light source and focuses it directly on the recording layer, which may be useful for a compact optical data storage system. The convex ellipsoidal surface of the PE SIM can reduce the risk of the SIM touching the surface of the recording medium. In addition, the spreading of the spot size with the increase of distance is very small in the PE SIM.

  6. Manchester's Magiscope: An Interesting Optics Puzzle

    ERIC Educational Resources Information Center

    Lancor, Rachael; Lancor, Brian

    2017-01-01

    The Magiscope was an attraction at Manchester's department store in Madison, WI, in 1939 that allowed children to peek into Santa's workshop (as shown in Fig. 1). The "magiscope" was a telescope-like device that gave children the illusion they were looking at a distant Santa, when in fact they were looking at a fabricated workshop on an…

  7. Optical Storage Systems for Records and Information Management: Overview, Recommendations and Guidelines for Local Governments. Local Government Records Technical Information Series. Number 45.

    ERIC Educational Resources Information Center

    Schwartz, Stanley F.

    This publication discusses optical storage, a term encompassing technologies that use laser-produced light to record and store information in digital form. The booklet also discusses how optical storage systems relate to records management, in particular to the management of local government records in New York State. It describes components of…

  8. Additive, modular functionalization of reactive self-assembled monolayers: toward the fabrication of multilevel optical storage media.

    PubMed

    Gentili, Denis; Barbalinardo, Marianna; Manet, Ilse; Durso, Margherita; Brucale, Marco; Mezzi, Alessio; Melucci, Manuela; Cavallini, Massimiliano

    2015-04-28

    We report a novel strategy based on iterative microcontact printing, which provides additive, modular functionalization of reactive SAMs by different functional molecules. We demonstrate that after printing the molecules form an interpenetrating network at the SAM surface preserving their individual properties. We exploited the process by fabricating new optical storage media that consist of a multilevel TAG.

  9. Semiconductor/Solid Electrolyte Junctions for Optical Information Storage. Electrochromic Effects on Heptylviologen Incorporated within a Solid Polymer Electrolyte Cell.

    DTIC Science & Technology

    1986-05-15

    cathode5 . Electrochromic devices based upon these electrochemically reversible viologen redox couples would greatly benefit by their incorporation...electrolyte analogs. Here we wish to discuss some recent work from our laboratory on solid- state electrochromic cells in which heptyl viologen (HV2+) was...OPTICAL INFORMATION STORAGE. ELECTROCHROMIC EFFECTS QN HEPTYLVIOLOGEN INCORPORATED WITHIN A SOLID POLYMER ELECTROLYTE CELL By Anthony F. Sammells and

  10. Java-Library for the Access, Storage and Editing of Calibration Metadata of Optical Sensors

    NASA Astrophysics Data System (ADS)

    Firlej, M.; Kresse, W.

    2016-06-01

    The standardization of the calibration of optical sensors in photogrammetry and remote sensing has been discussed for more than a decade. Projects of the German DGPF and the European EuroSDR led to the abstract International Technical Specification ISO/TS 19159-1:2014 "Calibration and validation of remote sensing imagery sensors and data - Part 1: Optical sensors". This article presents the first software interface for a read- and write-access to all metadata elements standardized in the ISO/TS 19159-1. This interface is based on an xml-schema that was automatically derived by ShapeChange from the UML-model of the Specification. The software interface serves two cases. First, the more than 300 standardized metadata elements are stored individually according to the xml-schema. Secondly, the camera manufacturers are using many administrative data that are not a part of the ISO/TS 19159-1. The new software interface provides a mechanism for input, storage, editing, and output of both types of data. Finally, an output channel towards a usual calibration protocol is provided. The interface is written in Java. The article also addresses observations made when analysing the ISO/TS 19159-1 and compiles a list of proposals for maturing the document, i.e. for an updated version of the Specification.

  11. Halbach array type focusing actuator for small and thin optical data storage device

    NASA Astrophysics Data System (ADS)

    Lee, Sung Q.; Park, Kang-Ho; Paek, Mun Chul

    2004-09-01

    The small form factor optical data storage devices are developing rapidly nowadays. Since it is designed for portable and compatibility with flesh memory, its components such as disk, head, focusing actuator, and spindle motor should be assembled within 5 mm. The thickness of focusing actuator is within 2 mm and the total working range is +/-100um, with the resolution of less than 1μm. Since the thickness is limited tightly, it is hard to place the yoke that closes the magnetic circuit and hard to make strong flux density without yoke. Therefore, Halbach array is adopted to increase the magnetic flux of one side without yoke. The proposed Halbach array type focusing actuator has the advantage of thin actuation structure with sacrificing less flex density than conventional magnetic array. The optical head unit is moved on the swing arm type tracking actuator. Focusing coil is attached to swing arm, and Halbach magnet array is positioned at the bottom of deck along the tracking line, and focusing actuator exerts force by the Fleming's left hand rule. The dynamics, working range, control resolution of focusing actuator are analyzed and performed.

  12. High-speed optoelectronic IC for multi-standards of optical storage system

    NASA Astrophysics Data System (ADS)

    Cha, Sanghyun; Jeong, Hawoong; Go, Chaedong; Park, Deukhee; Lee, Changseok; Kwon, Kyoungsoo; Lee, Jeashin

    2010-05-01

    The conventional scheme of optical pick-up unit (OPU) should require two or three optoelectronic integrated circuits (OEICs) to cover triple-wavelength λ =780nm, 650nm and 405nm). In order to reduce cost and waste of resources, onechip solution of the OEIC is required. In this paper, the OEIC is designed which can cover triple-wavelength and three optical storage standards which are compact disk (CD), digital versatile disk (DVD) and Blue-Ray. The OEIC has dualarrays of photodiodes because focus of laser is varied depending on wavelength. One of arrays senses the laser of λ =780nm and another senses the lasers of λ =650nm and λ =405nm. For low power consumption and small die area, one wideband transimpedance amplifier (TIA) is used for two photodiodes which are for CD and DVD or Blue-Ray, respectively. And two small size switches are included to select photodiodes. The PIN fingerdiode with N+ fingercathode is integrated to guarantee high performances for λ =405nm and 650nm. And the isolation area between adjacent photodiodes is made by floated P+ implant for reducing power-loss. The measured cutoff bandwidth of the OEIC is 210MHz for λ =405nm. The OEIC is fabricated in a 0.6- μm BiCMOS technology and dissipates 150mW for a single supply voltage of 5V. The active area is 1.4x1.2mm2.

  13. LEPTON ACCELERATORS AND COLLIDERS: Linear optics calibration and nonlinear optimization during the commissioning of the SSRF storage ring

    NASA Astrophysics Data System (ADS)

    Tian, Shun-Qiang; Zhang, Wen-Zhi; Li, Hao-Hu; Zhang, Man-Zhou; Hou, Jie; Zhou, Xue-Mei; Liu, Gui-Min

    2009-06-01

    Phase I commissioning of the SSRF storage ring on 3.0 GeV beam energy was started at the end of December 2007. A lot of encouraging results have been obtained so far. In this paper, calibrations of the linear optics during the commissioning are discussed, and some measured results about the nonlinearity given. Calibration procedure emphasizes correcting quadrupole magnetic coefficients with the Linear Optics from Closed Orbit (LOCO) technique. After fitting the closed orbit response matrix, the linear optics of the four test modes is substantially corrected, and the measured physical parameters agree well with the designed ones.

  14. Archive Storage Media Alternatives.

    ERIC Educational Resources Information Center

    Ranade, Sanjay

    1990-01-01

    Reviews requirements for a data archive system and describes storage media alternatives that are currently available. Topics discussed include data storage; data distribution; hierarchical storage architecture, including inline storage, online storage, nearline storage, and offline storage; magnetic disks; optical disks; conventional magnetic…

  15. Metaphors, Puzzles, and Teachers' Professional Knowledge.

    ERIC Educational Resources Information Center

    Munby, Hugh

    This paper presents two puzzles that have emerged in a series of completed and ongoing studies at Queen's University, Ontario. These puzzles concern teachers' professional knowledge, a term used to refer to the non-propositional forms of knowledge assumed to be of importance to professional action. This research assumed that the professional…

  16. The Crossword Puzzle in Teaching Earth Science

    ERIC Educational Resources Information Center

    McKenny, Charles J.

    1970-01-01

    By way of change of pace, students are asked to use as many terms as possible in the construction of a puzzle pattern on a blank matrix. The instructor selects one pattern and completes it in the form of a crossword puzzle to be used at the end of the unit. An example is given from a weather and climate unit. (NH)

  17. Advocacy: AASL Puts the Puzzle Together

    ERIC Educational Resources Information Center

    Johns, Sara Kelly

    2007-01-01

    School librarians work with people of all ages, abilities, and personalities; those people are the puzzle pieces that make advocacy for libraries effective. School librarians contribute to and use the resources of their state and national organizations' advocacy efforts. The completed picture of the puzzle is an excellent program with…

  18. Crucigramas: Crossword Puzzles for Primary Grades.

    ERIC Educational Resources Information Center

    Garcia, Maria H.

    This workbook is intended as an aid to the teacher of a bilingual/bicultural Spanish-English program in the primary grades. It contains modified crossword puzzles in Spanish, designed to accompany the Spanish Curricula Development Center Southwest Edition readers, Units 1-3, Kits 2-9. The puzzles are intended to aid in reinforcing reading words…

  19. Guerrilla Puzzling: A Model for Research

    ERIC Educational Resources Information Center

    Zimmer, Marc

    2007-01-01

    There are two main settings for puzzle solving in higher education: graduate programs, with professors and both graduate and postdoctoral students; and predominantly undergraduate institutions, with professors and students. Research programs at large universities are well-oiled puzzle-solving machines. Graduate students there work long, hard hours…

  20. Economics - A Puzzle: The People Power Solution.

    ERIC Educational Resources Information Center

    Bartlett, Glenda; Price, Marlene H.

    A third-grade class and fifth-grade remedial reading students gained a positive attitude toward contemporary economic problems by studying economics as a puzzle in this award-winning project. The following concepts were each approached as pieces of the puzzle to be solved: money, wants and needs, income, goods and services, scarcity, consumption…

  1. Experiments on the data recording of optical waveguide multilayer storage devices

    NASA Astrophysics Data System (ADS)

    Liang, Zhongcheng; Ding, Dongyan; Xie, Haiyan; Gu, Minfen; Chen, Jiabi; Zhuang, Songlin

    2005-12-01

    The basic principles of optical waveguide multilayer storage (WMS) device include recording data in the form of waveguide defects, reading data by collecting the scatter light from the waveguide defects, and restraining the cross talk between layers by taking the benefit of the waveguide structure. In this paper, we give some experimental results obtained by three different approaches of data recording. They are laser direct writing, photolithography and hot embossing. In the first method, a laser beam is focused on the top of a polymer film. The thermal effect alters the medium property locally at the focus point, which acts as the defect in the waveguide structure. The second method resorts to the processes of photolithography to record pits on the photoresist layer. The process of hot embossing is similar to the fabrication of CD-ROM, however, the data pits deeper than the wavelength are embossed on the polymer surface to increase the scattering efficiency. WMS devices based on different data writing methods are presented and the data scattering patterns are observed. The comparison between the different data writing approaches is made and discussed as well.

  2. Weird Stellar Pair Puzzles Scientists

    NASA Astrophysics Data System (ADS)

    2008-05-01

    Astronomers have discovered a speedy spinning pulsar in an elongated orbit around an apparent Sun-like star, a combination never seen before, and one that has them puzzled about how the strange system developed. Orbital Comparison Comparing Orbits of Pulsar and Its Companion to our Solar System. CREDIT: Bill Saxton, NRAO/AUI/NSF Click on image for full caption information and available graphics. "Our ideas about how the fastest-spinning pulsars are produced do not predict either the kind of orbit or the type of companion star this one has," said David Champion of the Australia Telescope National Facility. "We have to come up with some new scenarios to explain this weird pair," he added. Astronomers first detected the pulsar, called J1903+0327, as part of a long-term survey using the National Science Foundation's Arecibo radio telescope in Puerto Rico. They made the discovery in 2006 doing data analysis at McGill University, where Champion worked at the time. They followed up the discovery with detailed studies using the Arecibo telescope, the NSF's Robert C. Byrd Green Bank Telescope (GBT) in West Virginia, the Westerbork radio telescope in the Netherlands, and the Gemini North optical telescope in Hawaii. The pulsar, a city-sized superdense stellar corpse left over after a massive star exploded as a supernova, is spinning on its axis 465 times every second. Nearly 21,000 light-years from Earth, it is in a highly-elongated orbit that takes it around its companion star once every 95 days. An infrared image made with the Gemini North telescope in Hawaii shows a Sun-like star at the pulsar's position. If this is an orbital companion to the pulsar, it is unlike any companions of other rapidly rotating pulsars. The pulsar, a neutron star, also is unusually massive for its type. "This combination of properties is unprecedented. Not only does it require us to figure out how this system was produced, but the large mass may help us understand how matter behaves at extremely

  3. Impact of storage induced outgassing organic contamination on laser induced damage of silica optics at 351 nm.

    PubMed

    Bien-Aimé, K; Belin, C; Gallais, L; Grua, P; Fargin, E; Néauport, J; Tovena-Pecault, I

    2009-10-12

    The impact of storage conditions on laser induced damage density at 351 nm on bare fused polished silica samples has been studied. Intentionally outgassing of polypropylene pieces on silica samples was done. We evidenced an important increase of laser induced damage density on contaminated samples demonstrating that storage could limit optics lifetime performances. Atomic Force Microscopy (AFM) and Gas Chromatography -Mass Spectrometry (GC-MS) have been used to identify the potential causes of this effect. It shows that a small quantity of organic contamination deposited on silica surface is responsible for this degradation. Various hypotheses are proposed to explain the damage mechanism. The more likely hypothesis is a coupling between surface defects of optics and organic contaminants.

  4. Structural and optical properties of In doped Se-Te phase-change thin films: A material for optical data storage

    NASA Astrophysics Data System (ADS)

    Pathak, H. P.; Shukla, Nitesh; Kumar, Vipin; Dwivedi, D. K.

    2016-02-01

    Se75-xTe25Inx (x = 0, 3, 6, & 9) bulk glasses were obtained by melt quench technique. Thin films of thickness 400 nm were prepared by thermal evaporation technique at a base pressure of 10-6 Torr onto well cleaned glass substrate. a-Se75-xTe25Inx thin films were annealed at different temperatures for 2 h. As prepared and annealed films were characterized by X-ray diffraction and UV-Vis spectroscopy. The X-ray diffraction results show that the as-prepared films are of amorphous nature while it shows some poly-crystalline structure in amorphous phases after annealing. The optical absorption spectra of these films were measured in the wavelength range 400-1100 nm in order to derive the extinction and absorption coefficient of these films. It was found that the mechanism of optical absorption follows the rule of allowed non-direct transition. The optical band gap of as prepared and annealed films as a function of photon energy has been studied. The optical band gap is found to decrease with increase in annealing temperature in the present glassy system. It happens due to crystallization of amorphous films. The decrease in optical band gap due to annealing is an interesting behavior for a material to be used in optical storage. The optical band gap has been observed to decrease with the increase of In content in Se-Te glassy system.

  5. The RPA Atomization Energy Puzzle.

    PubMed

    Ruzsinszky, Adrienn; Perdew, John P; Csonka, Gábor I

    2010-01-12

    There is current interest in the random phase approximation (RPA), a "fifth-rung" density functional for the exchange-correlation energy. RPA has full exact exchange and constructs the correlation with the help of the unoccupied Kohn-Sham orbitals. In many cases (uniform electron gas, jellium surface, and free atom), the correction to RPA is a short-ranged effect that is captured by a local spin density approximation (LSDA) or a generalized gradient approximation (GGA). Nonempirical density functionals for the correction to RPA were constructed earlier at the LSDA and GGA levels (RPA+), but they are constructed here at the fully nonlocal level (RPA++), using the van der Waals density functional (vdW-DF) of Langreth, Lundqvist, and collaborators. While they make important and helpful corrections to RPA total and ionization energies of free atoms, they correct the RPA atomization energies of molecules by only about 1 kcal/mol. Thus, it is puzzling that RPA atomization energies are, on average, about 10 kcal/mol lower than those of accurate values from experiment. We find here that a hybrid of 50% Perdew-Burke-Ernzerhof GGA with 50% RPA+ yields atomization energies much more accurate than either one does alone. This suggests a solution to the puzzle: While the proper correction to RPA is short-ranged in some systems, its contribution to the correlation hole can spread out in a molecule with multiple atomic centers, canceling part of the spread of the exact exchange hole (more so than in RPA or RPA+), making the true exchange-correlation hole more localized than in RPA or RPA+. This effect is not captured even by the vdW-DF nonlocality, but it requires the different kind of full nonlocality present in a hybrid functional.

  6. PSQP -- Puzzle Solving by Quadratic Programming.

    PubMed

    Andalo, Fernanda; Taubin, Gabriel; Goldenstein, Siome

    2016-03-25

    In this article we present the first effective global method for the reconstruction of image puzzles comprising rectangle pieces - Puzzle Solving by Quadratic Programming (PSQP). The proposed novel mathematical formulation reduces the problem to the maximization of a constrained quadratic function, which is solved via a gradient ascent approach. The proposed method is deterministic and can deal with arbitrary identical rectangular pieces. We provide experimental results showing its effectiveness when compared to state-of-the-art approaches. Although the method was developed to solve image puzzles, we also show how to apply it to the reconstruction of simulated strip-shredded documents, broadening its applicability.

  7. PSQP: Puzzle Solving by Quadratic Programming.

    PubMed

    Andalo, Fernanda A; Taubin, Gabriel; Goldenstein, Siome

    2017-02-01

    In this article we present the first effective method based on global optimization for the reconstruction of image puzzles comprising rectangle pieces-Puzzle Solving by Quadratic Programming (PSQP). The proposed novel mathematical formulation reduces the problem to the maximization of a constrained quadratic function, which is solved via a gradient ascent approach. The proposed method is deterministic and can deal with arbitrary identical rectangular pieces. We provide experimental results showing its effectiveness when compared to state-of-the-art approaches. Although the method was developed to solve image puzzles, we also show how to apply it to the reconstruction of simulated strip-shredded documents, broadening its applicability.

  8. Use of optical storage for patent image retrieval: the U.S. Patent and Trademark Office's automated patent system

    NASA Astrophysics Data System (ADS)

    Jacobson, Stephen R.

    1990-08-01

    The Automated Patent System (APS) was designed, among other things, to assist the patent examiner in performing the patent search. It is a fully distributed system that uses custom-built high-resolution dual-display intelligent workstations, optical file servers, mainframes, and support computers networked together using Ethernet technology. The system is composed of two parts which are highly integrated: a full text search system and a patent image retrieval system. When fully deployed, APS will have an image data base of up to 30 terabytes being accessed from over 1000 workstations. The U.S. Patent and Trademark Office (PTO) has had problems with their optical drives, and although they are fairly stable today, we still experience a moderately high hardware failure rate. The optical drive problems include media instability, hardware design errors, vendor problems, and configuration control failures. We intend to purchase additional drives in the future, and are re-evaluating the exclusive use of optical storage in light of recent advances in magnetic storage technology.

  9. Optical cell for combinatorial in situ Raman spectroscopic measurements of hydrogen storage materials at high pressures and temperatures.

    PubMed

    Hattrick-Simpers, Jason R; Hurst, Wilbur S; Srinivasan, Sesha S; Maslar, James E

    2011-03-01

    An optical cell is described for high-throughput backscattering Raman spectroscopic measurements of hydrogen storage materials at pressures up to 10 MPa and temperatures up to 823 K. High throughput is obtained by employing a 60 mm diameter × 9 mm thick sapphire window, with a corresponding 50 mm diameter unobstructed optical aperture. To reproducibly seal this relatively large window to the cell body at elevated temperatures and pressures, a gold o-ring is employed. The sample holder-to-window distance is adjustable, making this cell design compatible with optical measurement systems incorporating lenses of significantly different focal lengths, e.g., microscope objectives and single element lenses. For combinatorial investigations, up to 19 individual powder samples can be loaded into the optical cell at one time. This cell design is also compatible with thin-film samples. To demonstrate the capabilities of the cell, in situ measurements of the Ca(BH(4))(2) and nano-LiBH(4)-LiNH(2)-MgH(2) hydrogen storage systems at elevated temperatures and pressures are reported.

  10. Green-Light Static Rewritable Optical Storage Properties of a Novel CuTCNQ Derivative Thin Film

    NASA Astrophysics Data System (ADS)

    Huang, Wu-Qiao; Wu, Yi-Qun; Gu, Dong-Hong; Gan, Fu-Xi

    2003-12-01

    A novel charge-transfer complex film: copper-(n-propyl ester 7,7,8,8- tetracyanoquinodimethane-2,5-ylene-(3-propionic acid)) (Cu-TCNQ(C2H4COOC3H7)2) was prepared by spin-coating. Absorption spectra, green-light (514.5 nm) static rewritable optical recording properties and rewritable mechanism of this film were studied. The results show that there are two strong absorption peaks at 388 nm and 675 nm, which can be assigned to electronic transitions in anion radical TCNQ(C2H4COOC3H7)2-. Green-light optical storage experimental results of this film were as follows: write-in power was 9 mW, pulse duration was 80 ns erasing power was 4 mW, pulse duration was 500 ns the reflectivity contrast Cgeq15% number of write-erase cycles Ngeq100. It is found that the realization of rewritable optical storage of the Cu-TCNQ(C2H4COOC3H7)2 film is related to the reversible changes of the optical properties, which is caused by the reversible charge transfer between copper and n-propyl ester 7,7,8,8- tetracyanoquinodimethane-2,5-ylene-(3-propionic acid) in the complex through inducement of laser irradiation.

  11. Optical cell for combinatorial in situ Raman spectroscopic measurements of hydrogen storage materials at high pressures and temperatures

    NASA Astrophysics Data System (ADS)

    Hattrick-Simpers, Jason R.; Hurst, Wilbur S.; Srinivasan, Sesha S.; Maslar, James E.

    2011-03-01

    An optical cell is described for high-throughput backscattering Raman spectroscopic measurements of hydrogen storage materials at pressures up to 10 MPa and temperatures up to 823 K. High throughput is obtained by employing a 60 mm diameter × 9 mm thick sapphire window, with a corresponding 50 mm diameter unobstructed optical aperture. To reproducibly seal this relatively large window to the cell body at elevated temperatures and pressures, a gold o-ring is employed. The sample holder-to-window distance is adjustable, making this cell design compatible with optical measurement systems incorporating lenses of significantly different focal lengths, e.g., microscope objectives and single element lenses. For combinatorial investigations, up to 19 individual powder samples can be loaded into the optical cell at one time. This cell design is also compatible with thin-film samples. To demonstrate the capabilities of the cell, in situ measurements of the Ca(BH4)2 and nano-LiBH4-LiNH2-MgH2 hydrogen storage systems at elevated temperatures and pressures are reported.

  12. Design, Installation and Post-Implementation Assessment of an Optical Disc Based Storage and Retrieval System for Images of Engineering Contract Documents.

    ERIC Educational Resources Information Center

    Ashford, J. H.; Masters, A. M.

    1992-01-01

    Describes an image storage system for contract documentation in the Engineering Directorate of Thames Water Utilities (England) which uses optical disc storage and a relational database for indexing and retrieval of nearly 500,000 pages in compressed image format, and provides end user access through 7 workstations. Requirements, feasibility…

  13. Design, Installation and Post-Implementation Assessment of an Optical Disc Based Storage and Retrieval System for Images of Engineering Contract Documents.

    ERIC Educational Resources Information Center

    Ashford, J. H.; Masters, A. M.

    1992-01-01

    Describes an image storage system for contract documentation in the Engineering Directorate of Thames Water Utilities (England) which uses optical disc storage and a relational database for indexing and retrieval of nearly 500,000 pages in compressed image format, and provides end user access through 7 workstations. Requirements, feasibility…

  14. The Mass Puzzle in Cosmology

    NASA Astrophysics Data System (ADS)

    Peebles, P. J. E.

    1993-05-01

    Attempts to fill in some of the details of the standard hot expanding world picture by appeal to the observational evidence lead to some fascinating dilemmas, many related to the puzzles of the nature and amount of the dark matter. Well tested approaches yield two quite different values for the distance scale, h ~ 0.5 and h ~ 0.8 (where Hubble's constant is H_o=100h km s(-1) Mpc(-1) ). If the shorter scale proved to be right the expansion timescale in an Einstein-de Sitter universe would be unacceptable; we would have to live in a low density universe, maybe with a significant cosmological constant. This is in the direction suggested by dynamical studies on scales <~ 10h(-1) Mpc, which quite consistently indicate a mean mass density Omega ~ 0.1 times the critical Einstein-de Sitter value. Dynamical measures on larger scales are less well explored, but there is a reasonable case that Omega is close to unity, as could fit the longer distance scale. But if Omega =1 we have a challenge: why does some 90%\\ of the mass appear to have resisted clustering on scales <~ 10h(-1) Mpc? Astrophysical biasing scenarios postulate galaxy formation was inhibited by unhealthy conditions in protovoids. But if the gross properties of galaxies were sensitive to environment, why do the galaxies that survived exhibit the striking environment-independent regularities of the Tully-Fisher relation and the fundamental planes? In some versions of the Omega = 1 cold dark matter and mixed dark matter models galaxies are assembled at low redshifts. If so, perhaps the Carlberg velocity biasing effect can account for the low apparent Omega in the small-scale dynamical tests. Galaxy assembly at low redshift certainly could agree with the apparent immaturity of galaxies at zgap 0.7, as indicated by the Butcher-Oemler effect and the alignment effect in radio galaxies. But if galaxy assembly were a recent phenomenon why do the Wolfe clouds at z ~ 3 look like young galaxies in an already well

  15. Oriental Puzzle Gives Students Graphics Practice.

    ERIC Educational Resources Information Center

    Reddick, David B.; Johnson, Terri

    1985-01-01

    Describes a class assignment in which graphics students use an ancient Chinese puzzle called a tangram. Students arrange the five triangles, one square, and one rhomboid into an animate and an inanimate object. (HTH)

  16. CP violation: Another piece of the puzzle

    NASA Astrophysics Data System (ADS)

    Durieux, Gauthier; Grossman, Yuval

    2017-04-01

    A study of Λb baryon decays has provided the first direct experimental evidence that spinning matter and antimatter differ. This result may help us understand the puzzling matter-antimatter imbalance in the Universe.

  17. CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES: Novel Bilayer Structures for Short Wavelength High Density Magneto-Optical Data Storage

    NASA Astrophysics Data System (ADS)

    Wang, Xian-Ying; Wang, Jing; Wang, Zhan-Yong; Yang, Jun-He

    2008-06-01

    We report a novel bi-layer thin film structure for high density magneto-optical (MO) data storage, which combines the advantages of blue wavelength and magnetically induced superresolution (MSR) recording. A double-layer system of exchange-coupled light rare-earth (LRE) element doped NdGdFeCo and traditional TbFeCo is used as the recording medium. The experimental results demonstrate that this NdGdFeCo/TbFeCo double layer has large Kerr rotation under blue wavelength. Centre aperture detection (CAD) MSR effect with temperature rising is also observed. Theoretical calculation is also carried out to verify the experimental results. These results collectively suggest that the new bilayer structure is very promising in next generation high density MO data storage.

  18. Compensation and Improvement of Intensity and Distribution in Reconstructed Image Using Adaptive Optics in Holographic Data Storage

    NASA Astrophysics Data System (ADS)

    Muroi, Tetsuhiko; Sekiguchi, Sayaka; Kinoshita, Nobuhiro; Ishii, Norihiko; Shimidzu, Naoki; Kamijo, Koji; Booth, Martin; Juskaitis, Rimas; Wilson, Tony

    2008-07-01

    We applied a genetic algorithm to adaptive optics to improve the intensity and distribution of reconstructed images in holographic data storage. This is a kind of combinatorial optimisation. In holographic data storage, the photopolymer recording medium shrinks during light curing and this shrinkage distorts the recorded interference fringes, which degrades the reconstructed data images. Although it is possible to compensate for the degradation in the reconstructed image by using adaptive optics, it has been difficult to compensate for the shrinkage distortion by using normal feedback control because the relationship between the reconstructed image and deformable mirror input is nonlinear. With our method, the inverse variance coefficient in a reconstructed image with bits that are all “1” increased from 10.3 to 14.7 dB, an improvement of 4.4 dB. Moreover, the intensity average of the reconstructed image with compensation was 1.7 times higher than the average without compensation. These results show that the combination of adaptive optics and a genetic algorithm is very effective for improving reconstructed images.

  19. Tornillos: Pieces of a Puzzle

    NASA Astrophysics Data System (ADS)

    Hellweg, M.; Seidl, D.

    2001-12-01

    In the past decade several of the ash eruptions at Galeras volcano (Colombia) have been preceded by tornillos. These unusual seismic events of unknown origin have screw-like profiles on seismograms and can last up to several minutes. Since 1997, a joint project between the Bundesanstalt für Geowissenschaften und Rohstoffe (BGR) and the Instituto de Investigación e Información Geocientífica, Minero-Ambiental y Nuclear (INGEOMINAS) has supplemented the shortperiod network of the Observatorio Vulcanológico de Pasto with four broadband, three-component seismometer stations, continuous fumarole gas chemistry measurments, electromagnetic sensors, an infrasound sensor and weather observations in the hopes to learn more about the physical or chemical process which generates tornillos and their significance in the sequence leading to ash explosions. The events of a suite of tornillos which occurred at Galeras Volcano between 08 December 1999 and 11 February 2000 were recorded well at the crater rim broadband stations, ANG and ACH. They appear to be more complex than many of the tornillos recorded previously. They are multichromatic, having narrow spectral peaks at up to 9 frequencies. Some peaks last throughout the entire tornillo, others only contribute to the turn-on transient. We compare polarization, frequency, amplitudes and decay measured from this suite of tornillos in each frequency band at the stations ANG and ACH. They indicate a single source location for all these tornillos. While other parameters correlate well at both stations, the amplitude of the 1.9 Hz peak is nearly twice as large at ACH than at ANG. This may indicate a distinct radiation pattern at this frequency. While none of these observations gives us a clear picture of the source process of tornillos, they provide additional puzzle pieces we can add those collected from other measurements.

  20. Carbon/Ternary Alloy/Carbon Optical Stack on Mylar as an Optical Data Storage Medium to Potentially Replace Magnetic Tape

    SciTech Connect

    Wang, Hao; Lunt, Barry M.; Gates, Richard J.; Asplund, Matthew C.; Shutthanandan, V.; Davis, Robert C.; Linford, Matthew R.

    2013-09-11

    A novel write-once-read-many (WORM) optical stack on Mylar tape is proposed as a replacement for magnetic tape for archival data storage. This optical tape contains a cosputtered bismuth–tellurium–selenium (BTS) alloy as the write layer sandwiched between thin, protective films of reactively sputtered carbon. The composition and thickness of the BTS layer were confirmed by Rutherford Backscattering (RBS) and atomic force microscopy (AFM), respectively. The C/BTS/C stack on Mylar was written to/marked by 532 nm laser pulses. Under the same conditions, control Mylar films without the optical stack were unaffected. Marks, which showed craters/movement of the write material, were characterized by optical microscopy and AFM. The threshold laser powers for making marks on C/BTS/C stacks with different thicknesses were explored. Higher quality marks were made with a 60× objective compared to a 40× objective in our marking apparatus. Finally, the laser writing process was simulated with COMSOL.

  1. Satisfiability modulo theory and binary puzzle

    NASA Astrophysics Data System (ADS)

    Utomo, Putranto

    2017-06-01

    The binary puzzle is a sudoku-like puzzle with values in each cell taken from the set {0, 1}. We look at the mathematical theory behind it. A solved binary puzzle is an n × n binary array where n is even that satisfies the following conditions: (1) No three consecutive ones and no three consecutive zeros in each row and each column, (2) Every row and column is balanced, that is the number of ones and zeros must be equal in each row and in each column, (3) Every two rows and every two columns must be distinct. The binary puzzle had been proven to be an NP-complete problem [5]. Research concerning the satisfiability of formulas with respect to some background theory is called satisfiability modulo theory (SMT). An SMT solver is an extension of a satisfiability (SAT) solver. The notion of SMT can be used for solving various problem in mathematics and industries such as formula verification and operation research [1, 7]. In this paper we apply SMT to solve binary puzzles. In addition, we do an experiment in solving different sizes and different number of blanks. We also made comparison with two other approaches, namely by a SAT solver and exhaustive search.

  2. The SeaWiFS Bio-Optical Archive and Storage System (SeaBASS): Current Architecture and Implementation

    NASA Technical Reports Server (NTRS)

    Werdell, P. Jeremy; Fargion, Giulietta S. (Editor); McClain, Charles R. (Editor); Bailey, Sean W.

    2002-01-01

    Satellite ocean color missions require an abundance of high-quality in situ measurements for bio-optical and atmospheric algorithm development and post-launch product validation and sensor calibration. To facilitate the assembly of a global data set, the NASA Sea-viewing Wide Field-of-view (SeaWiFS) Project developed the Seafaring Bio-optical Archive and Storage System (SeaBASS), a local repository for in situ data regularly used in their scientific analyses. The system has since been expanded to contain data sets collected by the NASA Sensor Intercalibration and Merger for Biological and Interdisciplinary Oceanic Studies (SIMBIOS) Project, as part of NASA Research Announcements NRA-96-MTPE-04 and NRA-99-OES-99. SeaBASS is a well moderated and documented hive for bio-optical data with a simple, secure mechanism for locating and extracting data based on user inputs. Its holdings are available to the general public with the exception of the most recently collected data sets. Extensive quality assurance protocols, comprehensive data and system documentation, and the continuation of an archive and relational database management system (RDBMS) suitable for bio-optical data all contribute to the continued success of SeaBASS. This document provides an overview of the current operational SeaBASS system.

  3. Laser Optical Disk: The Coming Revolution in On-Line Storage.

    ERIC Educational Resources Information Center

    Fujitani, Larry

    1984-01-01

    Review of similarities and differences between magnetic-based and optical disk drives includes a discussion of the electronics necessary for their operation; describes benefits, possible applications, and future trends in development of laser-based drives; and lists manufacturers of laser optical disk drives. (MBR)

  4. Application of Electron Beams in Space for Energy Storage and Optical Beam Generation,

    DTIC Science & Technology

    1978-04-01

    MIRROR -DRIFT __ SPACE BUNCHER OUTPUT RADIATION Fig. 6-Optical klystron I/ // CATCHER MAGNET - / PAIR OF CORNER MAGNETSI ~FORM AN ACHROMATIC SERVCO.Rl I...optical link will be unable to penetrate heavy cloud formations and will thus present availability problems in most regions of the world. CONCLUDING

  5. Development of a software interface for optical disk archival storage for a new life sciences flight experiments computer

    NASA Technical Reports Server (NTRS)

    Bartram, Peter N.

    1989-01-01

    The current Life Sciences Laboratory Equipment (LSLE) microcomputer for life sciences experiment data acquisition is now obsolete. Among the weaknesses of the current microcomputer are small memory size, relatively slow analog data sampling rates, and the lack of a bulk data storage device. While life science investigators normally prefer data to be transmitted to Earth as it is taken, this is not always possible. No down-link exists for experiments performed in the Shuttle middeck region. One important aspect of a replacement microcomputer is provision for in-flight storage of experimental data. The Write Once, Read Many (WORM) optical disk was studied because of its high storage density, data integrity, and the availability of a space-qualified unit. In keeping with the goals for a replacement microcomputer based upon commercially available components and standard interfaces, the system studied includes a Small Computer System Interface (SCSI) for interfacing the WORM drive. The system itself is designed around the STD bus, using readily available boards. Configurations examined were: (1) master processor board and slave processor board with the SCSI interface; (2) master processor with SCSI interface; (3) master processor with SCSI and Direct Memory Access (DMA); (4) master processor controlling a separate STD bus SCSI board; and (5) master processor controlling a separate STD bus SCSI board with DMA.

  6. Exciton storage in type-II quantum dots using the optical Aharonov-Bohm effect

    SciTech Connect

    Climente, Juan I.; Planelles, Josep

    2014-05-12

    We investigate the bright-to-dark exciton conversion efficiency in type-II quantum dots subject to a perpendicular magnetic field. To this end, we take the exciton storage protocol recently proposed by Simonin and co-workers [Phys. Rev. B 89, 075304 (2014)] and simulate its coherent dynamics. We confirm the storage is efficient in perfectly circular structures subject to weak external electric fields, where adiabatic evolution is dominant. In practice, however, the efficiency rapidly degrades with symmetry lowering. Besides, the use of excited states is likely unfeasible owing to the fast decay rates. We then propose an adaptation of the protocol which does not suffer from these limitations.

  7. Educational puzzles for understanding gastrointestinal physiology.

    PubMed

    Bailey, C M; Hsu, C T; DiCarlo, S E

    1999-06-01

    We developed four innovative, creative, and fun educational tools to promote active learning, enhance problem-solving skills, and encourage small group discussion. Furthermore, the tools encourage deductive reasoning and critical thinking rather than passive memorization of material. The tools include crossword puzzles, hidden messages, word scrambles, and word searches. These tools were developed using two computer programs: the Crossword Construction Kit and The New Puzzle Factory. Instructors are encouraged to optimize the value of the tools by using the additional options presented at the end of each of the puzzles. The additional options encourage students to become active learners by creating their own tools. Although the principles of these four tools can be adapted to many disciplines, these specific games focused on gastrointestinal physiology. Our goal was to create tools that can be used either inside or outside the classroom to complement and enhance the lecture.

  8. VUV optical ring resonator for Duke storage ring free electron laser

    SciTech Connect

    Park, S.H.; Litvinenko, V.N.; Madey, J.M.J.

    1995-12-31

    The conceptual design of the multifaceted-mirror ring resonator for Duke storage ring VUV FEL is presented. The expected performance of the OK-4 FEL with ring resonator is described. We discuss in this paper our plans to study reflectivity of VUV mirrors and their resistivity to soft X-ray spontaneous radiation from OK-4 undulator.

  9. Creating Word Search Puzzles with a Pedagogical Purpose.

    ERIC Educational Resources Information Center

    Kunz, Jay

    2002-01-01

    Examines ways that word search puzzles can be created and modified for use in the foreign language classroom. Examples show how word search puzzles can focus on a wide variety of vocabulary, grammar topics, and skills. (Author/VWL)

  10. Channel simulation and development of signal processing techniques for a scanner-based optical storage system

    NASA Astrophysics Data System (ADS)

    Pillai, Usha; Vijaya Kumar, Bhagavatula

    1998-10-01

    A scanner-based storage system employs a head mounted on a scanner which oscillates over the moving media. The head moves in an approximately sinusoidal path relative to the media at a high frequency, time-multiplexing the read/write signals of several tracks. The resulting multi-channel readback can yield higher data rates over a conventional system with a head that moves linearly relative to the media. Scanner-based storage systems are not commercially available at present. We are envisioning a system that uses an opto-electronic scanner, developed at CMU, in which the deflection of a laser beam is controlled by an input voltage. Since no mechanical motion is involved, this scanner has a high bandwidth which makes it well suited to our application.

  11. Optimized six-dimensional optical storage: a practicable way to large capacity and fast throughputs

    NASA Astrophysics Data System (ADS)

    Liu, Shangqing

    2015-08-01

    An optimized six-dimensional storage system has been investigated theoretically. The system uses multiple beams to create overlapped micro gratings as each storage cell. The cell capacity depends exponentially on the beam wavelength number. With two-photon absorption writing, coherence tomography reading and superresolving beam focusing, this system has extra-large capacity of >1 Pbyte per DVD sized disk (potential ~60 Pbytes per disk), extra-fast reading speed of >117 Gbits/s with high signal-to-noise ratio of >66 dB, large cell sizes (~0.3μm × 6μm) which greatly reduce data addressing difficulties and a standard drive like structure compatible with the CD and DVD disks.

  12. Puzzles in modern biology. I. Male sterility, failure reveals design

    PubMed Central

    Frank, Steven A.

    2016-01-01

    Many human males produce dysfunctional sperm. Various plants frequently abort pollen. Hybrid matings often produce sterile males. Widespread male sterility is puzzling. Natural selection prunes reproductive failure. Puzzling failure implies something that we do not understand about how organisms are designed. Solving the puzzle reveals the hidden processes of design. PMID:28004842

  13. Puzzles in modern biology. I. Male sterility, failure reveals design.

    PubMed

    Frank, Steven A

    2016-01-01

    Many human males produce dysfunctional sperm. Various plants frequently abort pollen. Hybrid matings often produce sterile males. Widespread male sterility is puzzling. Natural selection prunes reproductive failure. Puzzling failure implies something that we do not understand about how organisms are designed. Solving the puzzle reveals the hidden processes of design.

  14. Puzzle Pedagogy: A Use of Riddles in Mathematics Education

    ERIC Educational Resources Information Center

    Farnell, Elin

    2017-01-01

    In this article, I present a collection of puzzles appropriate for use in a variety of undergraduate courses, along with suggestions for relevant discussion. Logic puzzles and riddles have long been sources of amusement for mathematicians and the general public alike. I describe the use of puzzles in a classroom setting, and argue for their use as…

  15. Puzzle Pedagogy: A Use of Riddles in Mathematics Education

    ERIC Educational Resources Information Center

    Farnell, Elin

    2017-01-01

    In this article, I present a collection of puzzles appropriate for use in a variety of undergraduate courses, along with suggestions for relevant discussion. Logic puzzles and riddles have long been sources of amusement for mathematicians and the general public alike. I describe the use of puzzles in a classroom setting, and argue for their use as…

  16. Reinforcing Geometric Properties with Shapedoku Puzzles

    ERIC Educational Resources Information Center

    Wanko, Jeffrey J.; Nickell, Jennifer V.

    2013-01-01

    Shapedoku is a new type of puzzle that combines logic and spatial reasoning with understanding of basic geometric concepts such as slope, parallelism, perpendicularity, and properties of shapes. Shapedoku can be solved by individuals and, as demonstrated here, can form the basis of a review for geometry students as they create their own. In this…

  17. Bullet-Block Science Video Puzzle

    ERIC Educational Resources Information Center

    Shakur, Asif

    2015-01-01

    A science video blog, which has gone viral, shows a wooden block shot by a vertically aimed rifle. The video shows that the block hit dead center goes exactly as high as the one shot off-center. (Fig. 1). The puzzle is that the block shot off-center carries rotational kinetic energy in addition to the gravitational potential energy. This leads a…

  18. Exploring Organic Mechanistic Puzzles with Molecular Modeling

    ERIC Educational Resources Information Center

    Horowitz, Gail; Schwartz, Gary

    2004-01-01

    The molecular modeling was used to reinforce more general skills such as deducing and drawing reaction mechanisms, analyzing reaction kinetics and thermodynamics and drawing reaction coordinate energy diagrams. This modeling was done through the design of mechanistic puzzles, involving reactions not familiar to the students.

  19. Studying the Proton Spin Puzzle with PHENIX

    NASA Astrophysics Data System (ADS)

    Daugherity, Michael

    2012-03-01

    The proton spin puzzle remains one of the biggest mysteries in fundamental particle physics today. This talk will explore how the PHENIX Collaboration's forward W-boson program uses RHIC, the world's only polarized proton-proton collider, to probe the spin structure of the proton.

  20. Exploring Organic Mechanistic Puzzles with Molecular Modeling

    ERIC Educational Resources Information Center

    Horowitz, Gail; Schwartz, Gary

    2004-01-01

    The molecular modeling was used to reinforce more general skills such as deducing and drawing reaction mechanisms, analyzing reaction kinetics and thermodynamics and drawing reaction coordinate energy diagrams. This modeling was done through the design of mechanistic puzzles, involving reactions not familiar to the students.

  1. Bullet-Block Science Video Puzzle

    ERIC Educational Resources Information Center

    Shakur, Asif

    2015-01-01

    A science video blog, which has gone viral, shows a wooden block shot by a vertically aimed rifle. The video shows that the block hit dead center goes exactly as high as the one shot off-center. (Fig. 1). The puzzle is that the block shot off-center carries rotational kinetic energy in addition to the gravitational potential energy. This leads a…

  2. Storage capacity of an optically formed spatial filter for character recognition.

    PubMed

    Burckhardt, C B

    1967-08-01

    Optical spatial filtering has been proposed as a means of character recognition. The cross correlations between the unknown character and a number of stored masks are performed optically. In this paper an estimate is derived for the capacity of such a system, i.e., the number of masks one can store. Two estimates are made for the capacity. One holds for a noiseless optical system. The derivation of the second estimate takes into account noise of the photographic plate. Noise measurements of Kodak 649F plates are given. A numerical example shows the order of magnitude of the capacity. While, in our specific example, a capacity of several hundred thousand is computed for the noiseless system, this figure is reduced by two orders of magnitudes for the noisy system.

  3. Improved optical storage properties of NaAlSiO4: Tb3+ induced by Bi3+

    NASA Astrophysics Data System (ADS)

    Zhou, Junhe; Yu, Xue; Wang, Ting; Zhou, Dacheng; Qiu, Jianbei

    2016-07-01

    NaAlSiO4: Tb3+, Bi3+ phosphor was synthesized with green long persistent luminescence (LPL) and photo-stimulated luminescence (PSL) observed. The influence of metal ion Bi3+ on the optical storage properties of NaAlSiO4: Tb3+ was investigated in detail. The emitter Tb3+ introduced two kinds of traps located at 350 K (TA) and 440 K (TB) in the thermoluminescence (TL) glow curve. Bi3+ as a codopant ion introduced a new trap peaking at 390 K (TC), which contributed to the improved LPL properties. Besides, owing to the existence of deep and stable trap TB, green PSL can still be observed after 72 h since the excitation was stopped. Accordingly, the mechanism of LPL and PSL process was discussed briefly.

  4. Body Temperature Controlled Optical and Thermal Information Storage Light Scattering Display with Fluorescence Effect and High Mechanical Strength.

    PubMed

    Chen, Si; Tong, Xiaoqian; He, Huiwen; Ma, Meng; Shi, Yanqin; Wang, Xu

    2017-04-05

    A kind of body temperature controlled optical and thermal information storage light scattering display based on super strong liquid crystalline physical gel with special "loofah-like gel network" was successfully prepared. Such liquid crystal (LC) gel was obtained by mixing a dendritic gelator (POSS-G1-BOC), an azobenzene compound (2Azo2), and a phosphor tethered liquid crystalline host (5CB), which could show its best contrast ratio at around human body temperature under UV light because of the phosphor's fluorescence effect. The gel also has quite strong mechanical strength, which could be used in wearable device field especially under sunlight, even under the forcing conditions as harsh as being centrifuged for 10 min at the speed of 2000 r/min. The whole production process of such a display is quite simple and could lead to displays at any size through noncontact writing. We believe it will have wide applications in the future.

  5. Using Optical Disk as the Storage Media Device for the Master Personnel Files.

    DTIC Science & Technology

    1986-04-01

    EVALUATI ON OF OPTI CAL DISKS * Background------------------------------------------------ 4 Materials Used/Embedding Information Process -------------5...Mater ial s Used-------------------------------------- 5 Embedding Information Process ---------------------- 6 * Opt ical Disk Capabilities...EMBEDDING INFORMATION PROCESS The optical disk looks very similar to the common phonograph record but is composed of a material that undergoes an

  6. Optical Discs for Storage and Access in ARL Libraries. SPEC KIT 133.

    ERIC Educational Resources Information Center

    Holibaugh, Ralph

    This SPEC (Systems and Procedures Exchange Center) kit provides a sample of excerpts from technical and planning documents contributed by 40 Association of Research Libraries (ARL) member libraries that are planning to install or have already implemented optical disc technology. Selected to represent a variety of media and applications, the…

  7. Precision Spectroscopy of Atomic Hydrogen and the Proton Size Puzzle

    NASA Astrophysics Data System (ADS)

    Udem, Thomas

    2016-05-01

    Precise determination of transition frequencies of simple atomic systems are required for a number of fundamental applications such as tests of quantum electrodynamics (QED), the determination of fundamental constants and nuclear charge radii. The sharpest transition in atomic hydrogen occurs between the metastable 2S state and the 1S ground state. Its transition frequency has now been measured with almost 15 digits accuracy using an optical frequency comb and a cesium atomic clock as a reference. A recent measurement of the Lamb shift in muonic hydrogen is in significant contradiction to the hydrogen data if QED calculations are assumed to be correct. We hope to contribute to the resolution of this so called `proton size puzzle' by providing additional experimental input from the hydrogen side.

  8. Encrypted optical storage with wavelength-key and random phase codes.

    PubMed

    Matoba, O; Javidi, B

    1999-11-10

    An encrypted optical memory system that uses a wavelength code as well as input and Fourier-plane random phase codes is proposed. Original data are illuminated by a coherent light source with a specified wavelength and are then encrypted with two random phase codes before being stored holographically in a photorefractive material. Successful decryption requires the use of a readout beam with the same wavelength as that used in the recording, in addition to the correct phase key in the Fourier plane. The wavelength selectivity of the proposed system is evaluated numerically. We show that the number of available wavelength keys depends on the correlation length of the phase key in the Fourier plane. Preliminary experiments of encryption and decryption of optical memory in a LiNbO(3):Fe photorefractive crystal are demonstrated.

  9. Room temperature optical image storage devices based on novel photo-responsive chiral azobenzene liquid crystal dopants

    NASA Astrophysics Data System (ADS)

    Chen, Si; Chen, Yining; Tong, Xiaoqian; Wu, Bozhen; Ma, Meng; Shi, Yanqin; Wang, Xu

    2016-11-01

    A room temperature optical image storage device based on a novel kind of chiral azobenzene liquid crystal compound (Azo-CC) dopant was reported in this paper, which could realize room temperature photocatalytic phase transition when doping in host liquid crystal E7. With a comparation of the referential achiral compound (Azo-ACC), the chemical structure, liquid crystalline and photoresponsive properties of the compounds were characterized by 1H-NMR, POM and UV-vis, respectively. The result showed that the compound with chiral group (Azo-CC) exhibited better photoresponsive properties than the referential achiral compound (Azo-ACC), indicating the introduction of chiral group is the key factor to provide E7 host room temperature photosensitive properties, which could not only made the liquid crystal molecular reoriented but also could change the whole nematic host liquid crystal to helical-twisted matrix. In addition, to understand the optical-switching behavior into detail, the photoisomerization dynamics of the systems o was also analyzed.

  10. Crossword Puzzles - A New Look at an Old Teaching Idea

    NASA Astrophysics Data System (ADS)

    Bradstreet, D. H.; Steelman, D. P.; Lewis, A.

    1998-05-01

    In the never-ending search for more effective pedagogical tools that don't greatly increase already heavy work loads, we have implemented computer generated and graded crossword puzzles as an integral part of our core-level two semester astronomy course. The puzzles are created using a commercially available puzzle generator, Crossword Compiler (written by A.L.), enabling the professor to easily create crossword puzzles from a word list and corresponding clues. For each chapter, a hard copy version of the puzzle is distributed to the students. The students must complete the puzzle and then enter its solution using a standard Internet browser via a Java applet written by us. A Java application, placed on a campus network server, provides the puzzles to the applet and records the student scores. The students' work is automatically graded and the name, time of submission, score, etc. is stored in a file on the server for the professor's later retrieval. A Java application, able to run on multiple platforms, is used by the instructor to easily submit new puzzles to the server, set up dates for puzzle availability, and retrieve student scores. The instructor has complete control over when puzzles are available and when they are automatically taken off the server. This keeps the students up to date in their studying of the course material. The students' reactions to the puzzles have been excellent. They actually complain if the puzzles aren't provided! The puzzles force the students to carefully read and study the text and class handout notes. This is the most effective (and enjoyable) tool that we have ever found for making students become familiar with terminology and concepts. The programs will be demonstrated and sample hard-copy puzzles provided. The network-based Java programs will eventually be made available at little or no cost to interested institutions.

  11. Optical and thermal properties of nickel(II) hydrazone complex for recordable blu-ray storage

    NASA Astrophysics Data System (ADS)

    Chen, Zhimin; Wu, Yiqun; Gu, Donghong; Gan, Fuxi

    2009-08-01

    A nickel(II) hydrazone complex was synthesized in order to obtain a suitable optical recording medium for the new generation recordable blu-ray disk. Smooth thin films of the nickel(II) hydrazone complex were prepared by using the spin-coating method. Absorption and reflectance spectra of the thin films were evaluated in the wavelength 300-700 nm. Thermal properties of the nickel(II) complex were investigated by thermogravimetry (TG) and differential scanning calorimetry (DSC). Optical constants (complex refractive indices N=n+ik) and thickness of the thin film, prepared on single-crystal silicon substrate, were investigated on a rotating analyzer-polarizer scanning ellipsometer in the wavelength 285-705 nm. In addition, in order to examine its possible use as a blu-ray recording medium, the spin-coated film of the nickel(II) complex was prepared on K9 glass substrate with a silver reflective layer, and was studied by static optical recording testing system with a 406.7 nm laser. It is found that the absorption spectra of the thin film has an strong absorption band in the wavelength region 360-420 nm and a moderate absorbance at the 405 nm side, which indicates that the absorption of the film is well matched with the laser wavelength of the 405 nm. The reflectance spectra show that a high reflectivity of the thin film at 405 nm wavelength can be obtained by an optimum film thickness and an appropriate metal reflective layer. The thin film of the nickel(II) complex gives a high n value of 1.62 and a low k value of 0.33, corresponding to the wavelength of the blue laser of 405 nm. Measurements of the thermal properties show that the nickel(II) complex holds a high thermal stability (~ 300 °C) and a sharp weight loss which are helpful to fabricate a small and sharp recording mark edge. The results of the static optical recording test, using the nickel(II) complex thin film as the recording layer, demonstrate that high reflectivity contrast (>50 %) can be obtained at

  12. How to resolve the proton radius puzzle?

    NASA Astrophysics Data System (ADS)

    Paz, Gil

    2016-09-01

    In 2010 the first measurement of the proton charge radius from spectroscopy of muonic hydrogen was found to be five standard deviations away from the regular hydrogen value. Six years later, this ``proton radius puzzle'' is still unresolved. One of the most promising avenues to test the muonic hydrogen result is a new muon-proton scattering experiment called MUSE. We describe how effective field theory methods will allow to directly connect muonic hydrogen spectroscopy to muon-proton scattering.

  13. Helicity-dependent all-optical switching in hybrid metal-ferromagnet structures for ultrafast magnetic data storage

    NASA Astrophysics Data System (ADS)

    Cheng, Feng

    The emerging Big Data era demands the rapidly increasing need for speed and capacity of storing and processing information. Standalone magnetic recording devices, such as hard disk drives (HDDs), have always been playing a central role in modern data storage and continuously advancing. Recognizing the growing capacity gap between the demand and production, industry has pushed the bit areal density in HDDs to 900 Giga-bit/square-inch, a remarkable 450-million-fold increase since the invention of the first hard disk drive in 1956. However, the further development of HDD capacity is facing a pressing challenge, the so-called superparamagnetic effect, that leads to the loss of information when a single bit becomes too small to preserve the magnetization. This requires new magnetic recording technologies that can write more stable magnetic bits into hard magnetic materials. Recent research has shown that it is possible to use ultrafast laser pulses to switch the magnetization in certain types of magnetic thin films. Surprisingly, such a process does not require an externally applied magnetic field that always exists in conventional HDDs. Furthermore, the optically induced magnetization switching is extremely fast, up to sub-picosecond (10 -12 s) level, while with traditional recording method the deterministic switching does not take place shorter than 20 ps. It's worth noting that the direction of magnetization is related to the helicity of the incident laser pulses. Namely, the right-handed polarized laser pulses will generate magnetization pointing in one direction while left-handed polarized laser pulses generate magnetization pointing in the other direction. This so-called helicity-dependent all-optical switching (HD-AOS) phenomenon can be potentially used in the next-generation of magnetic storage systems. In this thesis, I explore the HD-AOS phenomenon in hybrid metal-ferromagnet structures, which consist of gold and Co/Pt multilayers. The experiment results show

  14. Optical storage in azobenzene-containing epoxy polymers processed as Langmuir Blodgett films.

    PubMed

    Fernández, Raquel; Mondragon, Iñaki; Sanfelice, Rafaela C; Pavinatto, Felippe J; Oliveira, Osvaldo N; Oyanguren, Patricia; Galante, María J

    2013-04-01

    In this study, azocopolymers containing different main-chain segments have been synthesized with diglycidyl ether of bisphenol A (DGEBA, DER 332, n=0.03) and the azochromophore Disperse Orange 3 (DO3) cured with two monoamines, viz. benzylamine (BA) and m-toluidine (MT). The photoinduced birefringence was investigated in films produced with these azopolymers using the spin coating (SC) and Langmuir Blodgett (LB) techniques. In the LB films, birefringence increased with the content of azochromophore and the film thickness, as expected. The nanostructured nature of the LB films led to an enhanced birefringence and faster dynamics in the writing process, compared to the SC films. In summary, the combination of azocopolymers and the LB method may allow materials with tuned properties for various optical applications, including in biological systems were photoisomerization may be used to trigger actions such as drug delivery.

  15. Useful laser source criteria for optical storage employing extended eye-diagram jitter theory

    NASA Astrophysics Data System (ADS)

    Kubota, Shigeo; Oka, Michio; Eguchi, Naoya; Fukumoto, Atsushi; Akiyama, Yoshiyuki

    1995-03-01

    In view of the recent progress in visible lasers for next-generation optical disks, we describe the influence of source wavelength, aberration, and noise on eye-diagram jitter, which determines the ultimate disk density. The analysis indicates that the sources used in a readout of a 6 \\times areal density, (4,22) run-length-limited code with a minimum mark length of 0.4 mu m must have a wavelength that satisfies the Nyquist condition of relationship between the spot size and the minimum mark length, a wave-front aberration of less than 0.035 rms lambda , and relative intensity noise of less than -125 dB/Hz.

  16. A method for simultaneous linear optics and coupling correction for storage rings with turn-by-turn beam position monitor data

    NASA Astrophysics Data System (ADS)

    Yang, Xi; Huang, Xiaobiao

    2016-08-01

    We propose a method to simultaneously correct linear optics errors and linear coupling for storage rings using turn-by-turn (TbT) beam position monitor (BPM) data. The independent component analysis (ICA) method is used to isolate the betatron normal modes from the measured TbT BPM data. The betatron amplitudes and phase advances of the projections of the normal modes on the horizontal and vertical planes are then extracted, which, combined with dispersion measurement, are used to fit the lattice model. The fitting results are used for lattice correction. The method has been successfully demonstrated on the NSLS-II storage ring.

  17. A method for simultaneous linear optics and coupling correction for storage rings with turn-by-turn beam position monitor data

    SciTech Connect

    Yang, Xi; Huang, Xiaobiao

    2016-05-13

    Here, we propose a method to simultaneously correct linear optics errors and linear coupling for storage rings using turn-by-turn (TbT) beam position monitor (BPM) data. The independent component analysis (ICA) method is used to isolate the betatron normal modes from the measured TbT BPM data. The betatron amplitudes and phase advances of the projections of the normal modes on the horizontal and vertical planes are then extracted, which, combined with dispersion measurement, are used to fit the lattice model. The fitting results are used for lattice correction. Finally, the method has been successfully demonstrated on the NSLS-II storage ring.

  18. A method for simultaneous linear optics and coupling correction for storage rings with turn-by-turn beam position monitor data

    SciTech Connect

    Yang, Xi; Huang, Xiaobiao

    2016-08-01

    We propose a method to simultaneously correct linear optics errors and linear coupling for storage rings using turn-by-turn (TbT) beam position monitor (BPM) data. The independent component analysis (ICA) method is used to isolate the betatron normal modes from the measured TbT BPM data. The betatron amplitudes and phase advances of the projections of the normal modes on the horizontal and vertical planes are then extracted, which, combined with dispersion measurement, are used to fit the lattice model. Furthermore, the fitting results are used for lattice correction. Our method has been successfully demonstrated on the NSLS-II storage ring.

  19. A method for simultaneous linear optics and coupling correction for storage rings with turn-by-turn beam position monitor data

    DOE PAGES

    Yang, Xi; Huang, Xiaobiao

    2016-05-13

    Here, we propose a method to simultaneously correct linear optics errors and linear coupling for storage rings using turn-by-turn (TbT) beam position monitor (BPM) data. The independent component analysis (ICA) method is used to isolate the betatron normal modes from the measured TbT BPM data. The betatron amplitudes and phase advances of the projections of the normal modes on the horizontal and vertical planes are then extracted, which, combined with dispersion measurement, are used to fit the lattice model. The fitting results are used for lattice correction. Finally, the method has been successfully demonstrated on the NSLS-II storage ring.

  20. Application of optical remote sensing techniques to quantify emissions from urban oil wells, storage tanks, and other small stationary sources

    NASA Astrophysics Data System (ADS)

    Pikelnaya, O.; Polidori, A.; Tisopulos, L.; Mellqvist, J.; Samuelsson, J.; Robinson, R. A.; Innocenti, F.; Perry, S.

    2016-12-01

    Oil fields in the Los Angeles Basin remain very productive even after more than a century-long history of exploration. There are currently over 5,000 active oil wells the South Coast Air Basin (SCAB), with a large portion placed in close proximity of residences, schools and other sensitive receptors. Gaseous emissions from oil wells and equipment related to oil extraction can have a significant impact on air quality. The South Coast Air Quality Management District (SCAQMD) and other state regulatory agencies have a number of rules aimed to reduce Volatile Organic Compound (VOC) emissions and to minimize potential impacts to nearby communities. However, little information is available on the effectiveness of current control measures and magnitude of emissions remain largely unknown. To fill this knowledge gap, in the fall of 2015 the SCAQMD, Fluxsense Inc., the National Physical Laboratory (NPL), and Kassay Field Services Inc. conducted a comprehensive five-week study to measure gaseous emissions from oil wells, oil pumps, intermediate storage tanks, and other small point sources. A combination of optical remote sensing (ORS) techniques was used to detect and quantify emissions VOCs, methane, nitrogen oxides (NOx) and other gaseous pollutants. Fluxsense used Solar Occultation Flux (SOF), Differential Optical Absorption Spectroscopy (DOAS), and Extractive Fourier Transform Infrared (FTIR) spectroscopy to survey a large number of oil extraction sites and other small emission sources within SCAB. Similarly, Kassay Field Services carried out open-path FTIR measurements to complement observations provided by Fluxsense. Concurrently, NPL operated their Differential Absorption Lidar (DIAL) system on a smaller sub-set of sources to validate the emission results provided by Fluxsense and Kassay. During this presentation we will discuss the results of this joined measurement effort and the potential impacts of the observed emissions on neighboring communities. Additionally

  1. Calibration of Fast Fiber-Optic Beam Loss Monitors for the Advanced Photon Source Storage Ring Superconducting Undulators

    SciTech Connect

    Dooling, J.; Harkay, K.; Ivanyushenkov, Y.; Sajaev, V.; Xiao, A.; Vella, Andrea K.

    2015-01-01

    We report on the calibration and use of fast fiber-optic (FO) beam loss monitors (BLMs) in the Advanced Photon Source storage ring (SR). A superconducting undulator prototype (SCU0) has been operating in SR Sector 6 (“ID6”) since the beginning of CY2013, and another undulator SCU1 (a 1.1-m length undulator that is three times the length of SCU0) is scheduled for installation in Sector 1 (“ID1”) in 2015. The SCU0 main coil often quenches during beam dumps. MARS simulations have shown that relatively small beam loss (<1 nC) can lead to temperature excursions sufficient to cause quenchingwhen the SCU0windings are near critical current. To characterize local beam losses, high-purity fused-silica FO cables were installed in ID6 on the SCU0 chamber transitions and in ID1 where SCU1 will be installed. These BLMs aid in the search for operating modes that protect the SCU structures from beam-loss-induced quenching. In this paper, we describe the BLM calibration process that included deliberate beam dumps at locations of BLMs. We also compare beam dump events where SCU0 did and did not quench.

  2. Effects of Chain Parameters on Kinetics of Photochromism in Acrylic-Spiropyran Copolymer Nanoparticles and Their Reversible Optical Data Storage.

    PubMed

    Sharifian, Mohammad Hossain; Mahdavian, Ali Reza; Salehi-Mobarakeh, Hamid

    2017-08-15

    Chemical bonding between photochromic compounds and polymer matrices will induce several consitions such as photostability, photoreversibility, elimination of dye aggregation, and undesirable negative photochromism. In such polymeric systems, the switching rate and photoisomerization are closely dependent on several parameters like chain flexibility, steric restrictions, polarity, and even proticity of the surrounding medium. Here, copolymerization of a synthesized spiropyran-based monomer with butyl acrylate (BA) and methyl methacrylate (MMA) comonomers was carried out with various compositions of MMA and BA through emulsion polymerization, and the corresponding photoisomerization kinetics were studied. Particle sizes and their distributions were analyzed by dynamic light scattering, and morphologies were investigated by scanning and transmission electron microscopic analyses. The results showed the particles are spherical with diameter 62-82 nm. Differential scanning calorimetric thermograms were employed to determine Tg of the prepared copolymers, which ranged from -23 to 93 °C. The kinetics of photoisomerization was then studied by UV-vis spectroscopy. Finally, a latex containing spiropyran/acrylic copolymer with Tg of about 0 °C and optimum rate of coloration and decoloration was considered in reversible optical data storage studies due to its fast photochromism and good film-formation properties.

  3. High flux circularly polarized gamma beam factory: coupling a Fabry-Perot optical cavity with an electron storage ring

    PubMed Central

    Chaikovska, I.; Cassou, K.; Chiche, R.; Cizeron, R.; Cornebise, P.; Delerue, N.; Jehanno, D.; Labaye, F.; Marie, R.; Martens, A.; Peinaud, Y.; Soskov, V.; Variola, A.; Zomer, F.; Cormier, E.; Lhermite, J.; Dolique, V.; Flaminio, R.; Michel, C.; Pinard, L.; Sassolas, B.; Akagi, T.; Araki, S.; Honda, Y.; Omori, T.; Terunuma, N.; Urakawa, J.; Miyoshi, S.; Takahashi, T.; Yoshitama, H.

    2016-01-01

    We report and discuss high-flux generation of circularly polarized γ-rays by means of Compton scattering. The γ-ray beam results from the collision of an external-cavity-enhanced infrared laser beam and a low emittance relativistic electron beam. By operating a non-planar bow-tie high-finesse optical Fabry-Perot cavity coupled to a storage ring, we have recorded a flux of up to (3.5 ± 0.3) × 108 photons per second with a mean measured energy of 24 MeV. The γ-ray flux has been sustained for several hours. In particular, we were able to measure a record value of up to 400 γ-rays per collision in a full bandwidth. Moreover, the impact of Compton scattering on the electron beam dynamics could be observed resulting in a reduction of the electron beam lifetime correlated to the laser power stored in the Fabry-Perot cavity. We demonstrate that the electron beam lifetime provides an independent and consistent determination of the γ-ray flux. Furthermore, a reduction of the γ-ray flux due to intrabeam scattering has clearly been identified. These results, obtained on an accelerator test facility, warrant potential scaling and revealed both expected and yet unobserved effects. They set the baseline for further scaling of the future Compton sources under development around the world. PMID:27857146

  4. Color-Coded Batteries - Electro-Photonic Inverse Opal Materials for Enhanced Electrochemical Energy Storage and Optically Encoded Diagnostics.

    PubMed

    O'Dwyer, Colm

    2016-07-01

    For consumer electronic devices, long-life, stable, and reasonably fast charging Li-ion batteries with good stable capacities are a necessity. For exciting and important advances in the materials that drive innovations in electrochemical energy storage (EES), modular thin-film solar cells, and wearable, flexible technology of the future, real-time analysis and indication of battery performance and health is crucial. Here, developments in color-coded assessment of battery material performance and diagnostics are described, and a vision for using electro-photonic inverse opal materials and all-optical probes to assess, characterize, and monitor the processes non-destructively in real time are outlined. By structuring any cathode or anode material in the form of a photonic crystal or as a 3D macroporous inverse opal, color-coded "chameleon" battery-strip electrodes may provide an amenable way to distinguish the type of process, the voltage, material and chemical phase changes, remaining capacity, cycle health, and state of charge or discharge of either existing or new materials in Li-ion or emerging alternative battery types, simply by monitoring its color change.

  5. High flux circularly polarized gamma beam factory: coupling a Fabry-Perot optical cavity with an electron storage ring

    NASA Astrophysics Data System (ADS)

    Chaikovska, I.; Cassou, K.; Chiche, R.; Cizeron, R.; Cornebise, P.; Delerue, N.; Jehanno, D.; Labaye, F.; Marie, R.; Martens, A.; Peinaud, Y.; Soskov, V.; Variola, A.; Zomer, F.; Cormier, E.; Lhermite, J.; Dolique, V.; Flaminio, R.; Michel, C.; Pinard, L.; Sassolas, B.; Akagi, T.; Araki, S.; Honda, Y.; Omori, T.; Terunuma, N.; Urakawa, J.; Miyoshi, S.; Takahashi, T.; Yoshitama, H.

    2016-11-01

    We report and discuss high-flux generation of circularly polarized γ-rays by means of Compton scattering. The γ-ray beam results from the collision of an external-cavity-enhanced infrared laser beam and a low emittance relativistic electron beam. By operating a non-planar bow-tie high-finesse optical Fabry-Perot cavity coupled to a storage ring, we have recorded a flux of up to (3.5 ± 0.3) × 108 photons per second with a mean measured energy of 24 MeV. The γ-ray flux has been sustained for several hours. In particular, we were able to measure a record value of up to 400 γ-rays per collision in a full bandwidth. Moreover, the impact of Compton scattering on the electron beam dynamics could be observed resulting in a reduction of the electron beam lifetime correlated to the laser power stored in the Fabry-Perot cavity. We demonstrate that the electron beam lifetime provides an independent and consistent determination of the γ-ray flux. Furthermore, a reduction of the γ-ray flux due to intrabeam scattering has clearly been identified. These results, obtained on an accelerator test facility, warrant potential scaling and revealed both expected and yet unobserved effects. They set the baseline for further scaling of the future Compton sources under development around the world.

  6. Early Puzzle Play: A predictor of preschoolers’ spatial transformation skill

    PubMed Central

    Levine, S.C.; Ratliff, K.R.; Huttenlocher, J.; Cannon, J.

    2011-01-01

    Individual differences in spatial skill emerge prior to kindergarten entry. However, little is known about the early experiences that may contribute to these differences. The current study examines the relation between children’s early puzzle play and their spatial skill. Children and parents (n = 53) were observed at home for 90 minutes every four months (six times) between 2 and 4 years of age (26 to 46 months). When children were 4 years 6 months old, they completed a spatial task involving mental transformations of 2D shapes. Children who were observed playing with puzzles performed better on this task than those who did not, controlling for parent education, income, and overall parent word types. Moreover, among those children who played with puzzles, frequency of puzzle play predicted performance on the spatial transformation task. Although the frequency of puzzle play did not differ for boys and girls, the quality of puzzle play (a composite of puzzle difficulty, parent engagement, and parent spatial language) was higher for boys than girls. In addition, variation in puzzle play quality predicted performance on the spatial transformation task for girls but not boys. Implications of these findings as well as future directions for research on the role of the role of puzzle play in the development of spatial skill are discussed. PMID:22040312

  7. Early puzzle play: a predictor of preschoolers' spatial transformation skill.

    PubMed

    Levine, Susan C; Ratliff, Kristin R; Huttenlocher, Janellen; Cannon, Joanna

    2012-03-01

    Individual differences in spatial skill emerge prior to kindergarten entry. However, little is known about the early experiences that may contribute to these differences. The current study examined the relation between children's early puzzle play and their spatial skill. Children and parents (n = 53) were observed at home for 90 min every 4 months (6 times) between 2 and 4 years of age (26 to 46 months). When children were 4 years 6 months old, they completed a spatial task involving mental transformations of 2-dimensional shapes. Children who were observed playing with puzzles performed better on this task than those who did not, controlling for parent education, income, and overall parent word types. Moreover, among those children who played with puzzles, frequency of puzzle play predicted performance on the spatial transformation task. Although the frequency of puzzle play did not differ for boys and girls, the quality of puzzle play (a composite of puzzle difficulty, parent engagement, and parent spatial language) was higher for boys than for girls. In addition, variation in puzzle play quality predicted performance on the spatial transformation task for girls but not for boys. Implications of these findings as well as future directions for research on the role of puzzle play in the development of spatial skill are discussed.

  8. TOPICAL REVIEW The cosmological constant puzzle

    NASA Astrophysics Data System (ADS)

    Bass, Steven D.

    2011-04-01

    The accelerating expansion of the Universe points to a small positive vacuum energy density and negative vacuum pressure. A strong candidate is the cosmological constant in Einstein's equations of general relativity. Possible contributions are zero-point energies and the condensates associated with spontaneous symmetry breaking. The vacuum energy density extracted from astrophysics is 1056 times smaller than the value expected from quantum fields and standard model particle physics. Is the vacuum energy density time dependent? We give an introduction to the cosmological constant puzzle and ideas how to solve it.

  9. Storage Media for Microcomputers.

    ERIC Educational Resources Information Center

    Trautman, Rodes

    1983-01-01

    Reviews computer storage devices designed to provide additional memory for microcomputers--chips, floppy disks, hard disks, optical disks--and describes how secondary storage is used (file transfer, formatting, ingredients of incompatibility); disk/controller/software triplet; magnetic tape backup; storage volatility; disk emulator; and…

  10. Storage Media for Microcomputers.

    ERIC Educational Resources Information Center

    Trautman, Rodes

    1983-01-01

    Reviews computer storage devices designed to provide additional memory for microcomputers--chips, floppy disks, hard disks, optical disks--and describes how secondary storage is used (file transfer, formatting, ingredients of incompatibility); disk/controller/software triplet; magnetic tape backup; storage volatility; disk emulator; and…

  11. Optical Storage System for 0.4 mm Substrate Media Using 405 nm Laser Diode and Numerical Aperture 0.60/0.65 Objective Lens

    NASA Astrophysics Data System (ADS)

    Ko, Jungwan; Park, In Sik; Yoon, Du-Seop; Chung, Chong-Sam; Kim, Yoon-Gi; Ro, Myong-Do; Doh, Tae-Yong; Shin, Dong-Ho

    2001-03-01

    The most important application of the blue-laser optical storage system is the recording high-definition digital broadcasting. For this application, the next-generation blue laser optical storage system requires a data capacity of at least 2 h of a digital broadcasting data stream with a data transfer rate of 23.5 megabits per second (Mbps). In addition to the capacity goal, system compatibility with the conventional digital versatile disc (DVD) system as well as the compact disc (CD) system is important. In order to satisfy the requirements of blue-laser optical storage, a system for media with a substrates thickness of 0.4 mm was proposed, and improved molding technology, crosstalk cancellation technology, dynamic tilt compensation technology and quadrature phase shift keying (QPSK) modulated wobble addressing method were developed for the system. We confirm the feasibility of the proposed system for media with a 0.4 mm substrate using a 405 nm blue laser diode and objective lens with a numerical aperture (NA) of 0.6 (0.65 for rewritable system).

  12. Magic star puzzle for educational mathematics

    NASA Astrophysics Data System (ADS)

    Gan, Yee Siang; Fong, Wan Heng; Sarmin, Nor Haniza

    2013-04-01

    One of the interesting fields in recreational mathematics is the magic number arrangement. There are different kinds of arrays in the arrangement for a group of numbers. In particular, one of the arrays in magic number arrangement is called magic star. In fact, magic star involves combinatorics that contributes to geometrical analysis and number theory. Hence, magic star is suitable to be introduced as educational mathematics to cultivate interest in different area of mathematics. To obtain the solutions of normal magic stars of order six, the possible sets of numbers for every line in a magic star have been considered. Previously, the calculation for obtaining the solutions has been done manually which is time-consuming. Therefore, a programming code to generate all the fundamental solutions for normal magic star of order six without including the properties of rotation and reflection has been done. In this puzzle, a magic star puzzle is created by using Matlab software, which enables a user to verify the entries for the cells of magic star of order six. Moreover, it is also user-friendly as it provides interactive commands on the inputs given by the user, which enables the user to detect the incorrect inputs. In addition, user can also choose to view all the fundamental solutions as generated by the programming code.

  13. A black hole of puzzling lightness

    NASA Image and Video Library

    2017-01-09

    This image taken with the Advanced Camera for Surveys (ACS) onboard the NASA/ESA Hubble Space Telescope captures a galaxy in the Virgo constellation. This camera was installed in 2002, and its wide field of view is double that of its predecessor, capturing superb images with sharp image quality and enhanced sensitivity that can be seen here. The beautiful spiral galaxy visible in the centre of the image is catchily known as RX J1140.1+0307, and it presents an interesting puzzle. At first glance, this galaxy appears to be a normal spiral galaxy, much like the Milky Way, but first appearances can be deceptive! The Milky Way galaxy, like most large galaxies, has a supermassive black hole at its centre, but some galaxies are centred on lighter, intermediate-mass black holes. RX J1140.1+0307 is such a galaxy — in fact, it is centred on one of the lowest black hole masses known in any luminous galactic core. What puzzles scientists about this particular galaxy is that the calculations don’t add up. With such a relatively low mass for the central black hole, models for the emission from the object cannot explain the observed spectrum; unless there are other mechanisms at play in the interactions between the inner and outer parts of the accretion disc surrounding the black hole.

  14. Accelerating Student Learning of Technology Terms: "The Crossword Puzzle Exercise"

    ERIC Educational Resources Information Center

    Whisenand, Thomas G.; Dunphy, Steven M.

    2010-01-01

    The authors suggest using an alternative teaching methodology to impart knowledge regarding information systems phraseology and vocabulary. Specifically, a series of crossword puzzles or scrabbles are used to present information system (IS) terminology to students in an introductory business information systems course. The puzzle terms and answers…

  15. Crossword Puzzles as Learning Tools in Introductory Soil Science

    ERIC Educational Resources Information Center

    Barbarick, K. A.

    2010-01-01

    Students in introductory courses generally respond favorably to novel approaches to learning. To this end, I developed and used three crossword puzzles in spring and fall 2009 semesters in Introductory Soil Science Laboratory at Colorado State University. The first hypothesis was that crossword puzzles would improve introductory soil science…

  16. The Clock Is Ticking: Library Orientation as Puzzle Room

    ERIC Educational Resources Information Center

    Reade, Tripp

    2017-01-01

    Tripp Reade is the school librarian at Cardinal Gibbons High School in Raleigh, North Carolina. This article describes how he redesigned his school's library orientation program after learning about escape rooms and a variant known as puzzle rooms. Puzzle rooms present players with a set of challenges to solve; they require "teamwork,…

  17. Decoding Codewords: Statistical Analysis of a Newspaper Puzzle

    ERIC Educational Resources Information Center

    Meacock, Susan; Meacock, Geoff

    2012-01-01

    In recent years English newspapers have started featuring a number of puzzles other than the ubiquitous crossword. Many of the puzzles are of Japanese origin such as Sudoku, Kakuro or Hidato. However, one recent one is very English and is called variously Cross-code, Alphapuzzle or some other name. In this article, it will be known as Codeword.…

  18. A Puzzle Used to Teach the Cardiac Cycle

    ERIC Educational Resources Information Center

    Marcondes, Fernanda K.; Moura, Maria J. C. S.; Sanches, Andrea; Costa, Rafaela; Oliveira de Lima, Patricia; Groppo, Francisco Carlos; Amaral, Maria E. C.; Zeni, Paula; Gaviao, Kelly Cristina; Montrezor, Luís H.

    2015-01-01

    The aim of the present article is to describe a puzzle developed for use in teaching cardiac physiology classes. The puzzle presents figures of phases of the cardiac cycle and a table with five columns: phases of cardiac cycle, atrial state, ventricular state, state of atrioventricular valves, and pulmonary and aortic valves. Chips are provided…

  19. Sudoku Puzzles for First-Year Organic Chemistry Students

    ERIC Educational Resources Information Center

    Perez, Alice L.; Lamoureux, G.

    2007-01-01

    Sudoku puzzle was designed to teach about amino acids and functional groups to the students of undergraduate organic chemistry students. The puzzles focus on helping the student learn the name, 3-letter code and 1-letter code of common amino acids and functional groups.

  20. Enumerating Small Sudoku Puzzles in a First Abstract Algebra Course

    ERIC Educational Resources Information Center

    Lorch, Crystal; Lorch, John

    2008-01-01

    Two methods are presented for counting small "essentially different" sudoku puzzles using elementary group theory: one method (due to Jarvis and Russell) uses Burnside's counting formula, while the other employs an invariant property of sudoku puzzles. Ideas are included for incorporating this material into an introductory abstract algebra course.…

  1. Sudoku Puzzles for First-Year Organic Chemistry Students

    ERIC Educational Resources Information Center

    Perez, Alice L.; Lamoureux, G.

    2007-01-01

    Sudoku puzzle was designed to teach about amino acids and functional groups to the students of undergraduate organic chemistry students. The puzzles focus on helping the student learn the name, 3-letter code and 1-letter code of common amino acids and functional groups.

  2. WAIS-IV visual puzzles in a mixed clinical sample.

    PubMed

    Fallows, Robert R; Hilsabeck, Robin C

    2012-01-01

    Little is known about which cognitive functions underlie the new Visual Puzzles subtest of the Wechsler Adult Intelligence Scale - Fourth Edition (WAIS-IV). The purpose of this study was to investigate relationships between Visual Puzzles and common neuropsychological measures in a mixed clinical sample. A total of 44 veterans (75% men) were administered the WAIS-IV as part of a neuropsychological evaluation. Average age was 47.4 years (SD = 11.8), and average education was 13.8 years (SD = 2.3). Correlations were conducted to examine relationships between Visual Puzzles, demographic variables, and neuropsychological measures. Hierarchical regression analysis was used to determine which measures contributed the most variance to Visual Puzzles. Visual Puzzles correlated significantly with measures of visuospatial reasoning, verbal learning and recall, mental flexibility, processing speed, and naming, which accounted for 50% of the variance in Visual Puzzles performance. The results indicate that Visual Puzzles is not a pure measure of visuoperceptual reasoning, at least in a mixed clinical sample, because memory, mental flexibility, processing speed, and language abilities also contribute to successful performance of the task. Thus it may be important to consider other aspects of cognitive functioning when interpreting Visual Puzzles performance.

  3. GAMES AND PUZZLES FOR THE MORE ABLE STUDENT.

    ERIC Educational Resources Information Center

    GOLDSMITH, JOHN

    SUCH MATHEMATICAL GAMES AS DOMINOES FOR PRIMARY NUMBER RECOGNITION AND AS MILK BOTTLE TOPS FOR ADDITION AND SUBTRACTION ARE LISTED. A LIST OF SEVERAL MATH PROBLEMS, PUZZLES AND BRAIN TEASERS FOLLOW. QUIET GAMES OF PAPER CUTTING AND CROSS WORD PUZZLES FOR MATH VOCABULARY ARE INCLUDED. THE NEXT SECTION OF GAMES CONCERNS LANGUAGE. THESE INCLUDE…

  4. A Puzzle Used to Teach the Cardiac Cycle

    ERIC Educational Resources Information Center

    Marcondes, Fernanda K.; Moura, Maria J. C. S.; Sanches, Andrea; Costa, Rafaela; Oliveira de Lima, Patricia; Groppo, Francisco Carlos; Amaral, Maria E. C.; Zeni, Paula; Gaviao, Kelly Cristina; Montrezor, Luís H.

    2015-01-01

    The aim of the present article is to describe a puzzle developed for use in teaching cardiac physiology classes. The puzzle presents figures of phases of the cardiac cycle and a table with five columns: phases of cardiac cycle, atrial state, ventricular state, state of atrioventricular valves, and pulmonary and aortic valves. Chips are provided…

  5. Crossword Puzzles as Learning Tools in Introductory Soil Science

    ERIC Educational Resources Information Center

    Barbarick, K. A.

    2010-01-01

    Students in introductory courses generally respond favorably to novel approaches to learning. To this end, I developed and used three crossword puzzles in spring and fall 2009 semesters in Introductory Soil Science Laboratory at Colorado State University. The first hypothesis was that crossword puzzles would improve introductory soil science…

  6. Jigsaw Puzzles. Australian Early Childhood Resource Booklets, No. 3.

    ERIC Educational Resources Information Center

    Fleer, Marilyn

    This booklet examines the educational value of jigsaw puzzles and gives practical suggestions on how to select and make them for use by children ages 1 through 8. It asserts that jigsaw puzzles provide children with the opportunity to develop problem-solving strategies, and discusses a theory of adult-child interaction that encourages the…

  7. Enumerating Small Sudoku Puzzles in a First Abstract Algebra Course

    ERIC Educational Resources Information Center

    Lorch, Crystal; Lorch, John

    2008-01-01

    Two methods are presented for counting small "essentially different" sudoku puzzles using elementary group theory: one method (due to Jarvis and Russell) uses Burnside's counting formula, while the other employs an invariant property of sudoku puzzles. Ideas are included for incorporating this material into an introductory abstract algebra course.…

  8. Sharing Skills: Reach for a Book; Book Week Puzzle Packet.

    ERIC Educational Resources Information Center

    Bauer, Caroline Feller

    1986-01-01

    Reach for a Book is the theme for Children's Book Week 1986, and book presentations, activities, and exhibits to emphasize the joy of reading are listed. A Book Week Puzzle Packet provides two puzzles designed to reinforce the idea of using the card catalog to find materials on specific subjects. (EM)

  9. Permanent Electronic Storage of Angiographic Images in the Catheterization Laboratory: High-Resolution and Real-Time Acquisition on Optical Laserdiscs.

    PubMed

    Azancot; Krone; Eiferman; Guermonprez; Metzger; Le Dref O; Steg; Bonan; Lesperance; Hudon; Friolo; Beaufils

    1997-03-01

    The use of electronic ÒfilmlessÓ media for long-term archiving of coronary angiograms has been impeded by the problems of image storage and data transfer among institutions. Although long-term analogue storage of the images is presently feasible, and much less costly than digital storage, processing has been limited to a 625 lines video format, not optimal for high quality images. We developed a bi-directional 1249/625 lines converter, able to store and to replay high resolution (1249 lines) video images, from Component Record Video (CRV) Optical Laser (Analogue) Videodisks. Image quality and medical relevance were evaluated five ways: 1) Outside experts compared 593 static images stored on CRV discs to the same images stored in a high-resolution digital format blinded to source of image. The four experts found no visual or medical difference in 98% of evaluated images and minor differences in the remainder. The differences in the remaining images were not consistent among experts. 2) Two of the experts also compared the enhanced CRV optically stored image to the image obtained on simultaneously recorded 35mm cine film, and found the enhanced CRV stored image to be superior or similar, but never inferior to the film image. 3) 90 representatives from 63 outside institutions compared images from both a digital hard drive and the enhanced CRV optical (analogue) storage displayed at a Windows based digital workstation. During the test they were blinded as to the source of the images. The representatives found no difference in image resolution, quality, diagnostic accuracy, and medical relevance. 4) We evaluated quantitative coronary angiography (QCA) on standard coronary test phantoms using enhanced CRV stored images digitally processed. The correlation of the enhanced CRV image to the actual size of the phantom vessels was similar to the results obtained in the literature from digitally stored images. 5) 78 arterial measurements ranging 0.65 to 4.85 mm were

  10. Holography and Optical Storage

    NASA Astrophysics Data System (ADS)

    Imlau, Mirco; Fally, Martin; Burr, Geoffrey W.; Sincerbox, Glenn T.

    The term holography is composed of the Greek words holos (= whole) and graphein (= to record, to write), and thus summarizes the key aspects of its underlying principle: recording the complete wavefront of an object, i.e., its intensity as well as its phase. Interference and diffraction phenomena are employed to record and retrieve the full information, a technique pioneered by Dennis Gabor in 1948. He was honored with the Nobel prize in Physics in 1971, reflecting the general impact of holography on modern physics.

  11. High Capacity High Speed Optical Data Storage System Based on Diffraction-Free Nanobeam. Final Report, 09-02-98 to 03-17-99

    SciTech Connect

    Tin Aye

    1999-06-16

    Physical Optics Corporation (POC) investigated the development of an optical data storage system built around a current well-engineered high-speed optical disk system with an innovative diffraction-free micro-optical element to produce a beam {approximately}250 nm wide with {approximately}4-5 mm depth of focus, allowing the system to address data at {approximately}100 Mbits/second and to store it 100 to 1,000 times more densely ({approximately}10 Gbit/in.{sup 2}) than in present systems. In Phase 1 of this project POC completed a thorough feasibility study by system design and analysis, successfully demonstrated fabrication of the key components, and conducted a proof-of-principle experimental demonstration. Specifically, production of a subwavelength ({approximately}380 nm) large depth of focus ({approximately}4-5 mm) addressing beam was demonstrated by fabricating a special microdiffractive optical element and recording this beam on a standard optical recording disk coated with a photopolymer material.

  12. SOLVING THE PUZZLE OF SUBHALO SPINS

    SciTech Connect

    Wang, Yang; Lin, Weipeng; Pearce, Frazer R.; Lux, Hanni; Onions, Julian; Muldrew, Stuart I. E-mail: linwp@shao.ac.cn

    2015-03-10

    Investigating the spin parameter distribution of subhalos in two high-resolution isolated halo simulations, recent work by Onions et al. suggested that typical subhalo spins are consistently lower than the spin distribution found for field halos. To further examine this puzzle, we have analyzed simulations of a cosmological volume with sufficient resolution to resolve a significant subhalo population. We confirm the result of Onions et al. and show that the typical spin of a subhalo decreases with decreasing mass and increasing proximity to the host halo center. We interpret this as the growing influence of tidal stripping in removing the outer layers, and hence the higher angular momentum particles, of the subhalos as they move within the host potential. Investigating the redshift dependence of this effect, we find that the typical subhalo spin is smaller with decreasing redshift. This indicates a temporal evolution, as expected in the tidal stripping scenario.

  13. The electron screening puzzle and nuclear clustering

    SciTech Connect

    Spitaleri, C.; Bertulani, C. A.; Fortunato, L.; Vitturi, A.

    2016-02-12

    Accurate measurements of nuclear reactions of astrophysical interest within, or close to, the Gamow peak show evidence of an unexpected effect attributed to the presence of atomic electrons in the target. The experiments need to include an effective "screening" potential to explain the enhancement of the cross sections at the lowest measurable energies. Despite various theoretical studies conducted over the past 20 years and numerous experimental measurements, a theory has not yet been found that can explain the cause of the exceedingly high values of the screening potential needed to explain the data. Furthermore, in this letter we show that instead of an atomic physics solution of the "electron screening puzzle", the reason for the large screening potential values is in fact due to clusterization effects in nuclear reactions, in particular for reaction involving light nuclei.

  14. The electron screening puzzle and nuclear clustering

    DOE PAGES

    Spitaleri, C.; Bertulani, C. A.; Fortunato, L.; ...

    2016-02-12

    Accurate measurements of nuclear reactions of astrophysical interest within, or close to, the Gamow peak show evidence of an unexpected effect attributed to the presence of atomic electrons in the target. The experiments need to include an effective "screening" potential to explain the enhancement of the cross sections at the lowest measurable energies. Despite various theoretical studies conducted over the past 20 years and numerous experimental measurements, a theory has not yet been found that can explain the cause of the exceedingly high values of the screening potential needed to explain the data. Furthermore, in this letter we show thatmore » instead of an atomic physics solution of the "electron screening puzzle", the reason for the large screening potential values is in fact due to clusterization effects in nuclear reactions, in particular for reaction involving light nuclei.« less

  15. Bullet-Block Science Video Puzzle

    NASA Astrophysics Data System (ADS)

    Shakur, Asif

    2015-01-01

    A science video blog,1 which has gone viral, shows a wooden block shot by a vertically aimed rifle. The video2 shows that the block hit dead center goes exactly as high as the one shot off-center. (Fig. 1). The puzzle is that the block shot off-center carries rotational kinetic energy in addition to the gravitational potential energy. This leads a majority of the bloggers to claim that the block shot off-center should not go as high as the one shot dead center. Others have claimed that the energy tied up as rotational energy is insignificant and the two blocks should rise to the same height within experimental error.

  16. Building programmable jigsaw puzzles with RNA.

    PubMed

    Chworos, Arkadiusz; Severcan, Isil; Koyfman, Alexey Y; Weinkam, Patrick; Oroudjev, Emin; Hansma, Helen G; Jaeger, Luc

    2004-12-17

    One challenge in supramolecular chemistry is the design of versatile, self-assembling building blocks to attain total control of arrangement of matter at a molecular level. We have achieved reliable prediction and design of the three-dimensional structure of artificial RNA building blocks to generate molecular jigsaw puzzle units called tectosquares. They can be programmed with control over their geometry, topology, directionality, and addressability to algorithmically self-assemble into a variety of complex nanoscopic fabrics with predefined periodic and aperiodic patterns and finite dimensions. This work emphasizes the modular and hierarchical characteristics of RNA by showing that small RNA structural motifs can code the precise topology of large molecular architectures. It demonstrates that fully addressable materials based on RNA can be synthesized and provides insights into self-assembly processes involving large populations of RNA molecules.

  17. A PUZZLE INVOLVING GALACTIC BULGE MICROLENSING EVENTS

    SciTech Connect

    Cohen, Judith G.; Gould, Andrew; Johnson, Jennifer A.; Thompson, Ian B.; Feltzing, Sofia; Bensby, Thomas; Huang Wenjin; Melendez, Jorge; Lucatello, Sara; Asplund, Martin E-mail: gould@astronomy.ohio-state.edu E-mail: ian@obs.carnegiescience.edu E-mail: tbensby@eso.org E-mail: jorge@astro.up.pt E-mail: asplund@MPA-Garching.MPG.DE

    2010-03-01

    We study a sample of 16 microlensed Galactic bulge main-sequence turnoff region stars for which high-dispersion spectra have been obtained with detailed abundance analyses. We demonstrate that there is a very strong and highly statistically significant correlation between the maximum magnification of the microlensed bulge star and the value of the [Fe/H] deduced from the high resolution spectrum of each object. Physics demands that this correlation, assuming it to be real, be the result of some sample bias. We suggest several possible explanations, but are forced to reject them all, and are left puzzled. To obtain a reliable metallicity distribution in the Galactic bulge based on microlensed dwarf stars, it will be necessary to resolve this issue through the course of additional observations.

  18. The puzzle of TRPV4 channelopathies

    PubMed Central

    Nilius, Bernd; Voets, Thomas

    2013-01-01

    Hereditary channelopathies, that is, mutations in channel genes that alter channel function and are causal for the pathogenesis of the disease, have been described for several members of the transient receptor potential channel family. Mutations in the TRPV4 gene, encoding a polymodal Ca2+ permeable channel, are causative for several human diseases, which affect the skeletal system and the peripheral nervous system, with highly variable phenotypes. In this review, we describe the phenotypes of TRPV4 channelopathies and overlapping symptoms. Putative mechanisms to explain the puzzle, and how mutations in the same region of the channel cause different diseases, are discussed and experimental approaches to tackle this surprising problem are suggested. PMID:23306656

  19. Puzzle patterns: Research day interactive strategy.

    PubMed

    Bassendowski, Sandra L; Petrucka, Pammla M

    2006-01-01

    The article describes the planning, implementation, and assessment of an interactive strategy designed for a research day at the College of Nursing, University of Saskatchewan. A decision was made to use a creative, interactive strategy involving the use of large, blank jigsaw puzzles to generate a visual depiction of research interests and challenges faced by participants who represented graduate and undergraduate nursing students, faculty, and invited guests from government, health regions, and professional associations. Participants were asked the following questions - "What are you curious about in nursing and health care," and "What situations or questions in nursing need answers"? The strategy demonstrated the comprehensiveness of information that can be obtained through a short-turn around interactive strategy. Further, it also attests to the broad spectrum of interests within a single nursing education program and posits the potential for educators to undertake further thematic analysis to synthesize the data to inform research agendas.

  20. Solar Twins and the Barium Puzzle

    NASA Astrophysics Data System (ADS)

    Reddy, Arumalla B. S.; Lambert, David L.

    2017-08-01

    Several abundance analyses of Galactic open clusters (OCs) have shown a tendency for Ba but not for other heavy elements (La-Sm) to increase sharply with decreasing age such that Ba was claimed to reach [Ba/Fe] ≃ +0.6 in the youngest clusters (ages < 100 Myr) rising from [Ba/Fe] = 0.00 dex in solar-age clusters. Within the formulation of the s-process, the difficulty to replicate higher Ba abundance and normal La-Sm abundances in young clusters is known as the barium puzzle. Here, we investigate the barium puzzle using extremely high-resolution and high signal-to-noise spectra of 24 solar twins and measured the heavy elements Ba, La, Ce, Nd, and Sm with a precision of 0.03 dex. We demonstrate that the enhanced Ba ii relative to La-Sm seen among solar twins, stellar associations, and OCs at young ages (<100 Myr) is unrelated to aspects of stellar nucleosynthesis but has resulted from overestimation of Ba by standard methods of LTE abundance analysis in which the microturbulence derived from the Fe lines formed deep in the photosphere is insufficient to represent the true line broadening imposed on Ba ii lines by the upper photospheric layers from where the Ba ii lines emerge. Because the young stars have relatively active photospheres, Ba overabundances most likely result from the adoption of a too low value of microturbulence in the spectrum synthesis of the strong Ba ii lines but the change of microturbulence in the upper photosphere has only a minor affect on La-Sm abundances measured from the weak lines.

  1. Exfoliation syndrome: assembling the puzzle pieces.

    PubMed

    Pasquale, Louis R; Borrás, Terete; Fingert, John H; Wiggs, Janey L; Ritch, Robert

    2016-09-01

    To summarize various topics and the cutting edge approaches to refine XFS pathogenesis that were discussed at the 21st annual Glaucoma Foundation Think Tank meeting in New York City, Sept. 19-20, 2014. The highlights of three categories of talks on cutting edge research in the field were summarized. Exfoliation syndrome (XFS) is a systemic disorder with a substantial ocular burden, including high rates of cataract, cataract surgery complications, glaucoma and retinal vein occlusion. New information about XFS is akin to puzzle pieces that do not quite join together to reveal a clear picture regarding how exfoliation material (XFM) forms. Meeting participants concluded that it is unclear how the mild homocysteinemia seen in XFS might contribute to the disarrayed extracellular aggregates characteristic of this syndrome. Lysyl oxidase-like 1 (LOXL1) variants are unequivocally genetic risk factors for XFS but exactly how these variants contribute to the assembly of exfoliation material (XFM) remains unclear. Variants in a new genomic region, CACNA1A associated with XFS, may alter calcium concentrations at the cell surface and facilitate XFM formation but much more work is needed before we can place this new finding in proper context. It is hoped that various animal model and ex vivo systems will emerge that will allow for proper assembly of the puzzle pieces into a coherent picture of XFS pathogenesis. A clear understanding of XFS pathogenesis may lead to 'upstream solutions' to reduce the ocular morbidity produced by XFS. © 2015 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  2. Isoenergetic Polymorphism: The Puzzle of Tolazamide as a Case Study.

    PubMed

    Boldyreva, Elena V; Arkhipov, Sergey G; Drebushchak, Tatiana N; Drebushchak, Valeri A; Losev, Evgeniy A; Matvienko, Alexander A; Minkov, Vasily S; Rychkov, Denis A; Seryotkin, Yurii V; Stare, Jernej; Zakharov, Boris A

    2015-10-19

    In the present case study of tolazamide we illustrate how many seemingly contradictory results that have been obtained from experimental observations and theoretical calculations can finally start forming a consistent picture: a "puzzle put together". For many years, tolazamide was considered to have no polymorphs. This made this drug substance unique among the large family of sulfonylureas, which was known to be significantly more prone to polymorphism than many other organic compounds. The present work employs a broad and in-depth analysis that includes the use of optical microscopy, single-crystal and powder X-ray diffraction, IR and Raman spectroscopies, DSC, semiempirical PIXEL calculations and DFT of three polymorphs of tolazamide. This case study shows how the polymorphs of a molecular crystal can be overlooked even if discovered serendipitously on one of numerous crystallizations, and how very different molecular packings can be practically isoenergetic but still crystallize quite selectively and transform one into another irreversibly upon heating. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Digital image storage.

    PubMed

    Wallack, Seth

    2008-01-01

    Digital image archival requires less physical storage space, allows for rapid storage and retrieval and avoids loss in image quality over time or with image duplication compared with film storage. Because medical imaging data are critically important and, by law, must be stored in a safe, accessible manner, it is imperative not to have one computer error destroy all copies of the image data. Several options for image storage media are available including magnetic tape, optical media, spinning disks and solid state. Other considerations include on-site vs. off-site storage, redundancy, on-line vs. off-line storage, and removable storage media for disaster recovery. The different storage media can be used in different configurations to provide sufficient protection of digital data. Choose a storage system that will keep your data safe from unauthorized access, hardware failure, and clinic disasters.

  4. SeaWiFS technical report series. Volume 20: The SeaWiFS bio-optical archive and storage system (SeaBASS), part 1

    NASA Technical Reports Server (NTRS)

    Hooker, Stanford B. (Editor); Mcclain, Charles R.; Firestone, James K.; Westphal, Todd L.; Yeh, Eueng-Nan; Ge, Yuntao; Firestone, Elaine R.

    1994-01-01

    This document provides an overview of the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) Bio-Optical Archive and Storage System (SeaBASS), which will serve as a repository for numerous data sets of interest to the SeaWiFS Science Team and other approved investigators in the oceanographic community. The data collected will be those data sets suitable for the development and evaluation of bio-optical algorithms which include results from SeaWiFS Intercalibration Round-Robin Experiments (SIRREXs), prelaunch characterization of the SeaWiFS instrument by its manufacturer -- Hughes/Santa Barbara Research Center (SBRC), Marine Optical Characterization Experiment (MOCE) cruises, Marine Optical Buoy (MOBY) deployments and refurbishments, and field studies of other scientists outside of NASA. The primary goal of the data system is to provide a simple mechanism for querying the available archive and requesting specific items, while assuring that the data is made available only to authorized users. The design, construction, and maintenance of SeaBASS is the responsibility of the SeaWiFS Calibration and Validation Team (CVT). This report is concerned with documenting the execution of this task by the CVT and consists of a series of chapters detailing the various data sets involved. The topics presented are as follows: 1) overview of the SeaBASS file architecture, 2) the bio-optical data system, 3) the historical pigment database, 4) the SIRREX database, and 5) the SBRC database.

  5. Puzzling through General Chemistry: A Light-Hearted Approach to Engaging Students with Chemistry Content

    ERIC Educational Resources Information Center

    Boyd, Susan L.

    2007-01-01

    Several puzzles are designed to be used by chemistry students as learning tools and teach them basic chemical concepts. The topics of the puzzles are based on the chapters from Chemistry, The Central Science used in general chemistry course and the puzzles are in various forms like crosswords, word searches, number searches, puzzles based on…

  6. Teaching the Blue-Eyed Islanders Puzzle in a Liberal Arts Mathematics Course

    ERIC Educational Resources Information Center

    Shea, Stephen

    2012-01-01

    The blue-eyed islanders puzzle is an old and challenging logic puzzle. This is a narrative of an experience introducing a variation of this puzzle on the first day of classes in a liberal arts mathematics course for non-majors. I describe an exercise that was used to facilitate the class's understanding of the puzzle.

  7. Teaching the Blue-Eyed Islanders Puzzle in a Liberal Arts Mathematics Course

    ERIC Educational Resources Information Center

    Shea, Stephen

    2012-01-01

    The blue-eyed islanders puzzle is an old and challenging logic puzzle. This is a narrative of an experience introducing a variation of this puzzle on the first day of classes in a liberal arts mathematics course for non-majors. I describe an exercise that was used to facilitate the class's understanding of the puzzle.

  8. Solar System Puzzle Kit: An Activity for Earth and Space Science.

    ERIC Educational Resources Information Center

    Vogt, Gregory L.; Rosenberg, Carla B.

    This Solar System Puzzle Kit for grades 5-8, allows students to create an eight-cube paper puzzle of the solar system and may be duplicated for classroom use or used as a take home activity for children and parents. By assembling the puzzle, hand-coloring the bodies of the solar system, and viewing the puzzle's 12 sides, students can reinforce…

  9. Puzzling through General Chemistry: A Light-Hearted Approach to Engaging Students with Chemistry Content

    ERIC Educational Resources Information Center

    Boyd, Susan L.

    2007-01-01

    Several puzzles are designed to be used by chemistry students as learning tools and teach them basic chemical concepts. The topics of the puzzles are based on the chapters from Chemistry, The Central Science used in general chemistry course and the puzzles are in various forms like crosswords, word searches, number searches, puzzles based on…

  10. The Meibomian Puzzle: Combining Pieces Together

    PubMed Central

    Butovich, Igor A.

    2009-01-01

    The purpose of this review was to summarize the available information on lipidomic analysis of human meibum and tear film, and critically evaluate the pertinent past and present analytical procedures and results obtained in various laboratories. Human meibum was shown to be a very complex mixture of lipids of various classes. For decades, their exact structures have remained elusive. Because of the limitations of the then-current techniques, most of the complex lipids that constitute meibum could not be analyzed as whole molecules and required prior hydrolysis and/or transesterification of the entire lipid pool. These procedures effectively made it very difficult, and often impossible, to reconstruct the complete structures of the original intact compounds, which prompted us to call this The Meibomian Puzzle. Modern techniques such as high-performance liquid chromatography in combination with mass spectrometry help in solving this puzzle by allowing a researcher to detect and analyze intact molecules of complex lipid compounds, even if present in extremely low concentrations. This current de-facto standard procedure in lipidomic analysis of natural lipids and their mixtures is compared with other experimental techniques such as nuclear magnetic resonance spectroscopy, infrared spectroscopy, gas chromatography, and thin layer chromatography, among the others. The results obtained by older techniques, and their limitations and deficiencies are discussed. It appears that some of the earlier findings did not withstand a scrupulous re-evaluation and need to be modified and/or corrected. The most intriguing development is the virtual absence in meibum of typical phospholipids – an important group of amphiphilic compounds whose role in the human tear film was thought to be to stabilize the entire tear film structure. Instead, another group of previously unidentified compounds, very long chain (O-acyl)-omega-hydroxy fatty acids, appears to be a stabilizing factor which

  11. Formative Assessment Probes: Mountaintop Fossil: A Puzzling Phenomenon

    ERIC Educational Resources Information Center

    Keeley, Page

    2015-01-01

    This column focuses on promoting learning through assessment. This month's issue describes using formative assessment probes to uncover several ways of thinking about the puzzling discovery of a marine fossil on top of a mountain.

  12. Formative Assessment Probes: Mountaintop Fossil: A Puzzling Phenomenon

    ERIC Educational Resources Information Center

    Keeley, Page

    2015-01-01

    This column focuses on promoting learning through assessment. This month's issue describes using formative assessment probes to uncover several ways of thinking about the puzzling discovery of a marine fossil on top of a mountain.

  13. Laser-induced phase transitions of Ge2Sb2Te5 thin films used in optical and electronic data storage and in thermal lithography.

    PubMed

    Chu, Cheng Hung; Shiue, Chiun Da; Cheng, Hsuen Wei; Tseng, Ming Lun; Chiang, Hai-Pang; Mansuripur, Masud; Tsai, Din Ping

    2010-08-16

    Amorphous thin films of Ge(2)Sb(2)Te(5), sputter-deposited on a ZnS-SiO(2) dielectric layer, are investigated for the purpose of understanding the structural phase-transitions that occur under the influence of tightly-focused laser beams. Selective chemical etching of recorded marks in conjunction with optical, atomic force, and electron microscopy as well as local electron diffraction analysis are used to discern the complex structural features created under a broad range of laser powers and pulse durations. Clarifying the nature of phase transitions associated with laser-recorded marks in chalcogenide Ge(2)Sb(2)Te(5) thin films provides useful information for reversible optical and electronic data storage, as well as for phase-change (thermal) lithography.

  14. Understanding the E-ring puzzle

    NASA Astrophysics Data System (ADS)

    Hsu, S.; Horanyi, M.; Juhasz, A.; Kempf, S.; Sternovsky, Z.; Ye, S.

    2016-12-01

    The asymmetric structure of Saturn's E ring revealed by the Cassini instruments is the most significant, yet puzzling, finding about the large diffuse ring originating from the geologically active moon Enceladus. Azimuthally, the E ring appears to be an egg-shaped structure with the blunt side facing sunward. The ring's vertical structure, however, shows a global warpage that is symmetric with respect to Saturn's rotation axis. In this paper we consider the recently discovered noon-to-midnight electric field in Saturn's inner magnetosphere as the main cause for the observed E ring asymmetry. This electric field modifies and confines the longitude of orbital periapses of E ring grains differently from the "classic" E ring grain dynamics and may lead to a size-dependent, day-night asymmetric E ring structure. We will present the latest E ring dynamics simulation results including the effects of the noon-to-midnight electric field and the day-night plasma temperature asymmetry. For comparison, in situ measurements carried out by the Cassini Cosmic Dust Analyser as well as the Radio and Plasma Wave Science (with supporting laboratory experiments) instruments during different Saturn's seasons will be used to provide observational constraints on the E ring dynamical evolution. Finally, we will make a preliminary update about the overall E ring characteristics with and without the newly introduced electric field and the implications, such as interactions with the embedded moons.

  15. Peripartum cardiomyopathy: A puzzle closer to solution

    PubMed Central

    Fett, James D

    2014-01-01

    Peripartum cardiomyopathy (PPCM) represents new heart failure in a previously heart-healthy peripartum patient. It is necessary to rule out all other known causes of heart failure before accepting a diagnosis of PPCM. The modern era for PPCM in the United States and beyond began with the report of the National Institutes of Health PPCM Workshop in 2000, clarifying all then-currently known aspects of the disease. Since then, hundreds of publications have appeared, an indication of how devastating this disease can be to young mothers and their families and the urgent desire to find solutions for its cause and better treatment. The purpose of this review is to highlight the important advances that have brought us nearer to the solution of this puzzle, focusing on what we have learned about PPCM since 2000; and what still remains unanswered. Despite many improvements in outcome, we still do not know the actual triggers that initiate the pathological process; but realize that cardiac angiogenic imbalances resulting from complex pregnancy-related immune system and hormonal changes play a key role. PMID:24669290

  16. Solving the puzzle of autoimmunity: critical questions

    PubMed Central

    Smilek, Dawn E.

    2015-01-01

    Despite recent advances in delineating the pathogenic mechanisms of autoimmune disease, the puzzle that reveals the true picture of these diverse immunological disorders is yet to be solved. We know that the human leukocyte antigen (HLA) loci as well as many different genetic susceptibility loci with relatively small effect sizes predispose to various autoimmune diseases and that environmental factors are involved in triggering disease. Models for mechanisms of disease become increasingly complex as relationships between components of both the adaptive and innate immune systems are untangled at the molecular level. In this article, we pose some of the important questions about autoimmunity where the answers will advance our understanding of disease pathogenesis and improve the rational design of novel therapies. How is autoimmunity triggered, and what components of the immune response drive the clinical manifestations of disease? What determines whether a genetically predisposed individual will develop an autoimmune disease? Is restoring immune tolerance the secret to finding cures for autoimmune disease? Current research efforts seek answers to these big questions. PMID:25750735

  17. Solving the puzzle of autoimmunity: critical questions.

    PubMed

    Smilek, Dawn E; St Clair, E William

    2015-01-01

    Despite recent advances in delineating the pathogenic mechanisms of autoimmune disease, the puzzle that reveals the true picture of these diverse immunological disorders is yet to be solved. We know that the human leukocyte antigen (HLA) loci as well as many different genetic susceptibility loci with relatively small effect sizes predispose to various autoimmune diseases and that environmental factors are involved in triggering disease. Models for mechanisms of disease become increasingly complex as relationships between components of both the adaptive and innate immune systems are untangled at the molecular level. In this article, we pose some of the important questions about autoimmunity where the answers will advance our understanding of disease pathogenesis and improve the rational design of novel therapies. How is autoimmunity triggered, and what components of the immune response drive the clinical manifestations of disease? What determines whether a genetically predisposed individual will develop an autoimmune disease? Is restoring immune tolerance the secret to finding cures for autoimmune disease? Current research efforts seek answers to these big questions.

  18. Unwinding the von Willebrand factor strings puzzle.

    PubMed

    De Ceunynck, Karen; De Meyer, Simon F; Vanhoorelbeke, Karen

    2013-01-10

    von Willebrand factor (VWF) is amongst others synthesized by endothelial cells and stored as ultra-large (UL) VWF multimers in Weibel-Palade bodies. Although UL-VWF is proteolysed by ADAMTS13 (a disintegrin-like and metalloprotease domain with thrombospondin type-1 motif, number 13) on secretion from endothelial cells, in vitro experiments in the absence of ADAMTS13 have demonstrated that a proportion of these UL-VWF multimers remain anchored to the activated endothelium. These multimers unravel, bind platelets, and wave in the direction of the flow. These so-called VWF "strings" have also been visualized in vivo, lining the lumen of activated mesenteric veins of Adamts13(-/-) mice. Various studies have demonstrated the extraordinary length of these VWF strings, the availability of their platelet binding and ADAMTS13 cleavage sites, and the possible nature of their endothelial attachment. VWF strings are also capable of tethering leukocytes and parasite-infected red blood cells. However, the majority of studies have been performed in the absence of ADAMTS13, a condition only experienced in thrombotic thrombocytopenic purpura. A normal functional role of VWF strings in healthy persons or in other disease pathologies remains unclear. In this review, we discuss some of the puzzling characteristics of VWF strings, and we debate whether the properties of VWF strings in the absence of ADAMTS13 might be relevant for understanding (patho)physiologic mechanisms.

  19. Molecular-level interactions of an azopolymer and poly(dodecylmethacrylate) in mixed Langmuir and Langmuir-Blodgett films for optical storage.

    PubMed

    Ceridório, Lucinéia F; Balogh, Débora T; Caseli, Luciano; Cardoso, Marcos R; Viitala, Tapani; Mendonça, Cleber R; Oliveira, Osvaldo N

    2010-06-01

    The applicability of azopolymers in optical storage can be extended through the use of nanostructured films produced with the Langmuir-Blodgett (LB) technique, but the film properties need to be optimized since these polymers generally do not form stable Langmuir films to be transferred onto solid substrates. Here, photoinduced birefringence was investigated for mixed Langmuir-Blodgett films from the homopolymers 4-[N-ethyl-N-(2-methacryloxyethyl)]-4'-nitroazobenzene (HPDR1-MA) and poly(dodecylmethacrylate) (HPDod-MA). The interactions between these polymers were studied in Langmuir and LB films. Surface pressure-area isotherms pointed to molecular-level interactions for proportions of 51 mf%, 41 mf% and 31 mf% of HPDR1-MA. Phase segregation was not apparent in the BAM images, in which the morphology of the blend film was clearly different from that of the Langmuir films of neat homopolymers. Through PM-IRRAS, we noted that the interaction between the azopolymer and HPDod-MA affected the orientation of carbonyl groups. Strong interactions for the mixture with 41 mf% of poly(dodecylmethacrylate) led to stable Langmuir films that were transferred onto solid supports as LB films. The photoinduced birefringence of 101-layer mixed LB films show features that make these films useful for optical storage, with the advantage of short writing times in comparison to other azopolymer films.

  20. INVESTIGATION OF INORGANIC PHOTOTROPIC MATERIALS AS A BI-OPTIC ELEMENT APPLICABLE IN HIGH DENSITY STORAGE COMPUTER MEMORIES

    DTIC Science & Technology

    A general valuation of the various types of phototropic (i.e., reversible, light induced, color producing) phenomenon is given regarding the...application of phototropic material to bioptic high density storage media for compu er memories. The inorganic ’’F’’ center type phototropic systems were

  1. X-rays from Saturn Pose Puzzles

    NASA Astrophysics Data System (ADS)

    2004-03-01

    The first clear detection of X-rays from the giant, gaseous planet Saturn has been made with NASA's Chandra X-ray Observatory. Chandra's image shows that the X-rays are concentrated near Saturn's equator, a surprising result since Jupiter's X-ray emission is mainly concentrated near the poles. Existing theories cannot easily explain the intensity or distribution of Saturn's X-rays. Chandra observed Saturn for about 20 hours in April of 2003. The spectrum, or distribution with energy of the X-rays, was found to be very similar to that of X-rays from the Sun. "This indicates that Saturn's X-ray emission is due to the scattering of solar X-rays by Saturn's atmosphere," said Jan-Uwe Ness, of the University of Hamburg in Germany and lead author of a paper discussing the Saturn results in an upcoming issue of Astronomy & Astrophysics. "It's a puzzle, since the intensity of Saturn's X-rays requires that Saturn reflects X-rays fifty times more efficiently than the Moon." The observed 90 megawatts of X-ray power from Saturn's equatorial region is roughly consistent with previous observations of the X-radiation from Jupiter's equatorial region. This suggests that both giant, gaseous planets reflect solar X-rays at unexpectedly high rates. Further observations of Jupiter will be needed to test this possibility. The weak X-radiation from Saturn's south-polar region presents another puzzle (the north pole was blocked by Saturn's rings during this observation). Saturn's magnetic field, like that of Jupiter, is strongest near the poles. X-radiation from Jupiter is brightest at the poles because of auroral activity due to the enhanced interaction of high-energy particles from the Sun with its magnetic field. Since spectacular ultraviolet polar auroras have been observed to occur on Saturn, Ness and colleagues expected that Saturn's south pole might be bright in X-rays. It is not clear whether the auroral mechanism does not produce X-rays on Saturn, or for some reason concentrates

  2. Heavy quarkonium: progress, puzzles, and opportunities

    SciTech Connect

    Brambilla, N; Heltsley, B K; Vogt, R; Bodwin, G T; Eichten, E; Frawley, A D; Meyer, A B; Mitchell, R E; Papdimitriou, V; Petreczky, P; Petrov, A A; Robbe, P; Vairo, A; Andronic, A; Arnaldi, R; Artoisenet, P; Bali, G; Bertolin, A; Bettoni, D; Brodzicka, J; Bruno, G E; Caldwell, A; Catmore, J; Chang, C -H; Chao, K -T; Chudakov, E; Cortese, P; Crochet, P; Drutskoy, A; Ellwanger, U; Faccioli, P; Gabareen Mokhtar, A; Garcia i Tormo, X; Hanhart, C; Harris, F A; Kaplan, D M; Klein, S R; Kowalski, H; Lansberg, J -P; Levichev, E; Lombardo, V; Loureno, C; Maltoni, F; Mocsy, A; Mussa, R; Navarra, F S; Negrini, M; Nielsen, M; Olsen, S L; Pakhlov, P; Pakhlova, G; Peters, K; Polosa, A D; Qian, W; Qiu, J -W; Rong, G; Sanchis-Lozano, M A; Scomparin, E; Senger, P; Simon, F; Stracka, S; Sumino, Y; Voloshin, M; Weiss, C; Wohri, H K; Yuan, C -Z

    2011-02-01

    A golden age for heavy quarkonium physics dawned a decade ago, initiated by the confluence of exciting advances in quantum chromodynamics (QCD) and an explosion of related experimental activity. The early years of this period were chronicled in the Quarkonium Working Group (QWG) CERN Yellow Report (YR) in 2004, which presented a comprehensive review of the status of the field at that time and provided specific recommendations for further progress. However, the broad spectrum of subsequent breakthroughs, surprises, and continuing puzzles could only be partially anticipated. Since the release of the YR, the BESII program concluded only to give birth to BESIII; the $B$-factories and CLEO-c flourished; quarkonium production and polarization measurements at HERA, JLab, and the Tevatron matured; and heavy-ion collisions at RHIC have opened a window on the deconfinement regime. All these experiments leave legacies of quality, precision, and unsolved mysteries for quarkonium physics, and therefore beg for continuing investigations. The plethora of newly-found quarkonium-like states unleashed a flood of theoretical investigations into new forms of matter such as quark-gluon hybrids, mesonic molecules, and tetraquarks. Measurements of the spectroscopy, decays, production, and in-medium behavior of c\\bar{c}, b\\bar{b}, and b\\bar{c} bound states have been shown to validate some theoretical approaches to QCD and highlight lack of quantitative success for others. The intriguing details of quarkonium suppression in heavy-ion collisions that have emerged from RHIC have elevated the importance of separating hot- and cold-nuclear-matter effects in quark-gluon plasma studies. This review systematically addresses all these matters and concludes by prioritizing directions for ongoing and future efforts.

  3. Local associations and the barium puzzle

    NASA Astrophysics Data System (ADS)

    Reddy, Arumalla B. S.; Lambert, David L.

    2015-12-01

    We have observed high-dispersion echelle spectra of main-sequence stars in five nearby young associations - Argus, Carina-Near, Hercules-Lyra, Orion and Subgroup B4 - and derived abundances for elements ranging from Na to Eu. These are the first chemical abundance measurements for two of the five associations, while the remaining three associations are analysed more extensively in our study. Our results support the presence of chemical homogeneity among association members with a typical star-to-star abundance scatter of about 0.06 dex or less over many elements. The five associations show log ɛ(Li) consistent with their age and share a solar chemical composition for all elements with the exception of Ba. We find that all the heavy elements (Y, Zr, La, Ce, Nd, Sm and Eu) exhibit solar ratios, i.e. [X/Fe] ≃ 0, while Ba is overabundant by about 0.2-0.3 dex. The origin of the overabundance of Ba is a puzzle. Within the formulation of the s-process, it is difficult to create a higher Ba abundance without a similar increase in the s-process contributions to other heavy elements (La-Sm). Given that Ba is represented by strong lines of Ba II and La-Sm are represented by rather weak ionized lines, the suggestion, as previously made by other studies, is that the Ba abundance may be systematically overestimated by standard methods of abundance analysis perhaps because the upper reaches of the stellar atmospheres are poorly represented by standard model atmospheres. A novel attempt to analyse the Ba I line at 5535 Å gives a solar Ba abundance for stars with effective temperatures hotter than about 5800 K but increasingly subsolar Ba abundances for cooler stars with apparent Ba deficiencies of 0.5 dex at 5100 K. This trend with temperature may signal a serious non-local thermodynamical equilibrium effect on the Ba I line.

  4. Heavy quarkonium: progress, puzzles, and opportunities

    SciTech Connect

    Petreczky, P.; Brambilla, N.; Eidelman,S; B.K. Heltsley; Vogt, R.; Bodwiny, G.T.; Eichteny, E., et. al.

    2011-02-08

    A golden age for heavy quarkonium physics dawned a decade ago, initiated by the confluence of exciting advances in quantum chromodynamics (QCD) and an explosion of related experimental activity. The early years of this period were chronicled in the Quarkonium Working Group (QWG) CERN Yellow Report (YR) in 2004, which presented a comprehensive review of the status of the field at that time and provided specific recommendations for further progress. However, the broad spectrum of subsequent breakthroughs, surprises, and continuing puzzles could only be partially anticipated. Since the release of the YR, the BESII program concluded only to give birth to BESIII; the $B$-factories and CLEO-c flourished; quarkonium production and polarization measurements at HERA and the Tevatron matured; and heavy-ion collisions at RHIC have opened a window on the deconfinement regime. All these experiments leave legacies of quality, precision, and unsolved mysteries for quarkonium physics, and therefore beg for continuing investigations. The plethora of newly-found quarkonium-like states unleashed a flood of theoretical investigations into new forms of matter such as quark-gluon hybrids, mesonic molecules, and tetraquarks. Measurements of the spectroscopy, decays, production, and in-medium behavior of c{bar c}, b{bar b}, and b{bar c} bound states have been shown to validate some theoretical approaches to QCD and highlight lack of quantitative success for others. The intriguing details of quarkonium suppression in heavy-ion collisions that have emerged from RHIC have elevated the importance of separating hot- and cold-nuclear-matter effects in quark-gluon plasma studies. This review systematically addresses all these matters and concludes by prioritizing directions for ongoing and future efforts.

  5. Modular Extracellular Matrices: Solutions for the Puzzle

    PubMed Central

    Serban, Monica A.; Prestwich, Glenn D.

    2008-01-01

    The common technique of growing cells in two-dimensions (2-D) is gradually being replaced by culturing cells on matrices with more appropriate composition and stiffness, or by encapsulation of cells in three-dimensions (3-D). The universal acceptance of the new 3-D paradigm has been constrained by the absence of a commercially available, biocompatible material that offers ease of use, experimental flexibility, and a seamless transition from in vitro to in vivo applications. The challenge – the puzzle that needs a solution – is to replicate the complexity of the native extracellular matrix (ECM) environment with the minimum number of components necessary to allow cells to rebuild and replicate a given tissue. For use in drug discovery, toxicology, cell banking, and ultimately in reparative medicine, the ideal matrix would therefore need to be highly reproducible, manufacturable, approvable, and affordable. Herein we describe the development of a set of modular components that can be assembled into biomimetic materials that meet these requirements. These semi-synthetic ECMs, or sECMs, are based on hyaluronan derivatives that form covalently crosslinked, biodegradable hydrogels suitable for 3-D culture of primary and stem cells in vitro, and for tissue formation in vivo. The sECMs can be engineered to provide appropriate biological cues needed to recapitulate the complexity of a given ECM environment. Specific applications for different sECM compositions include stem cell expansion with control of differentiation, scar-free wound healing, growth factor delivery, cell delivery for osteochondral defect and liver repair, and development of vascularized tumor xenografts for personalized chemotherapy. PMID:18442709

  6. Energy Storage.

    ERIC Educational Resources Information Center

    Eaton, William W.

    Described are technological considerations affecting storage of energy, particularly electrical energy. The background and present status of energy storage by batteries, water storage, compressed air storage, flywheels, magnetic storage, hydrogen storage, and thermal storage are discussed followed by a review of development trends. Included are…

  7. Energy Storage.

    ERIC Educational Resources Information Center

    Eaton, William W.

    Described are technological considerations affecting storage of energy, particularly electrical energy. The background and present status of energy storage by batteries, water storage, compressed air storage, flywheels, magnetic storage, hydrogen storage, and thermal storage are discussed followed by a review of development trends. Included are…

  8. Three Modes of Hydrogeophysical Investigation: Puzzles, Mysteries, and Conundrums

    NASA Astrophysics Data System (ADS)

    Ferre, P. A.

    2011-12-01

    In an article in the New Yorker in 2007, Malcolm Gladwell discussed the distinction that national security expert Gregory Treverton has made between puzzles and mysteries. Specifically, puzzles are problems that we understand and that will eventually be solved when we amass enough information. (Think crossword puzzles.) Mysteries are problems for which we have the necessary information, but it is often overwhelmed by irrelevant or misleading input. To solve a mystery, we require improved analysis. (Think find-a-word.) Gladwell goes on to explain that, in the national security realm, the Cold War was a puzzle while the current national security condition is a mystery. I will discuss the past, current, and future trajectories of hydrogeophysics in terms of puzzles and mysteries. I will also add a third class of problem: conundrums - those for which we lack sufficient information about their structure to know how to solve them. A conundrum is a mystery with an unexpected twist. I hope to make the case that the future growth of hydrogeophysics lies in our ability to address this more challenging and more interesting class of problem.

  9. Optical disk archiving using a personal computer: a solution to image storage problems in diagnostic imaging departments.

    PubMed

    Parkin, A; Norwood, H; Erdentug, A; Hall, A J

    1990-01-01

    The paper describes an approach to solving the problem of providing a large-capacity image archive for diagnostic imaging departments at reasonable cost. Optical disk stores, when fitted retrospectively to scanners, are very expensive and may not be compatible with existing computer hardware. We describe the use of an industry standard personal computer (PC) linked to a standard 5 1/4-in. optical disk drive as a 'stand-alone' image store. Image data are transferred from the scanner using 8-in. floppy disks, and these are read into the PC using an attached 8-in. floppy disk drive and then transferred to the optical disk. The patient details (patient name, ID, date, etc.) are entered into a database program held on the PC and these are used to generate a reference pointer to the optical disk file through which the data can be retrieved. Data retrieval involves entering the patient details into the data base and inserting a blank 8-in. floppy disk into the drive attached to the PC. A sector copy is then made from the optical disk to the 8-in. floppy disk, which can then be used at the viewing station at the scanner. The system is flexible since it can accept data from a variety of sources in any format; it is also low cost and operates independently of the scanner. The hardware is industry standard, ensuring low maintenance costs.

  10. Light shutters and electro-optical storage devices from antiferroelectric liquid crystals of bent-shape molecules

    NASA Astrophysics Data System (ADS)

    Jakli, Antal; Chien, Liang-Chi; Kruerke, Daniel; Rauch, Sebastian; Sawade, Hans; Bault, Philippe; Heppke, Gerd; Fodor-Csorba, Katalin; Nair, Geetha G.

    2003-04-01

    Novel scattering-type displays using antiferroelectric smectic phases of liquid crystals of bent-shape molecules are reviewed and discussed. There can be two distinct states racemic and chiral that work in opposite ways. The racemic structure is scattering in the OFF state and is optically clear under sufficiently large (E~4-6V/m) electric fields. The chiral structure is transparent at zero fields and scattering in the field ON state. These two structures may be reversibly interchanged implying their use in devices that consume energy only during switching from one stable state to the other. After summarizing the previous results on the film thickness, driving voltage and temperature dependences of the light shutters, new results will be presented on a banana smectic material, which has an optically isotropic transparent antiferroelectric OFF state. We show that the optically isotropic and transparent OFF state can be reversibly switched to birefringent and scattering ferroelectric states in less than hundred microseconds.

  11. International Trade Network: Fractal Properties and Globalization Puzzle

    NASA Astrophysics Data System (ADS)

    Karpiarz, Mariusz; Fronczak, Piotr; Fronczak, Agata

    2014-12-01

    Globalization is one of the central concepts of our age. The common perception of the process is that, due to declining communication and transport costs, distance becomes less and less important. However, the distance coefficient in the gravity model of trade, which grows in time, indicates that the role of distance increases rather than decreases. This, in essence, captures the notion of the globalization puzzle. Here, we show that the fractality of the international trade system (ITS) provides a simple solution for the puzzle. We argue that the distance coefficient corresponds to the fractal dimension of ITS. We provide two independent methods, the box counting method and spatial choice model, which confirm this statement. Our results allow us to conclude that the previous approaches to solving the puzzle misinterpreted the meaning of the distance coefficient in the gravity model of trade.

  12. The B → πK puzzle and supersymmetry

    NASA Astrophysics Data System (ADS)

    Imbeault, Maxime; Baek, Seungwon; London, David

    2008-06-01

    At present, there are discrepancies between the measurements of several observables in B → πK decays and the predictions of the Standard Model (the " B → πK puzzle"). Although the effect is not yet statistically significant-it is at the level of ≳ 3 σ-it does hint at the presence of new physics. In this Letter, we explore whether supersymmetry (SUSY) can explain the B → πK puzzle. In particular, we consider the SUSY model of Grossman, Neubert and Kagan (GNK). We find that it is extremely unlikely that GNK explains the B → πK data. We also find a similar conclusion in many other models of SUSY. And there are serious criticisms of the two SUSY models that do reproduce the B → πK data. If the B → πK puzzle remains, it could pose a problem for SUSY models.

  13. International trade network: fractal properties and globalization puzzle.

    PubMed

    Karpiarz, Mariusz; Fronczak, Piotr; Fronczak, Agata

    2014-12-12

    Globalization is one of the central concepts of our age. The common perception of the process is that, due to declining communication and transport costs, distance becomes less and less important. However, the distance coefficient in the gravity model of trade, which grows in time, indicates that the role of distance increases rather than decreases. This, in essence, captures the notion of the globalization puzzle. Here, we show that the fractality of the international trade system (ITS) provides a simple solution for the puzzle. We argue that the distance coefficient corresponds to the fractal dimension of ITS. We provide two independent methods, the box counting method and spatial choice model, which confirm this statement. Our results allow us to conclude that the previous approaches to solving the puzzle misinterpreted the meaning of the distance coefficient in the gravity model of trade.

  14. The Puzzle of Science; Making Sense of Incomplete Information

    NASA Astrophysics Data System (ADS)

    Shorey, B. U.

    2015-12-01

    There are many topics within Earth science including evolution, historical geology, and climate change, which have gained the status of theory becuse they have overwhelming evidence, yet there is still fragmentary information which can frustrate a student from coming to solid conclusions. Using a jigsaw puzzle whose image has been hidden, and the pieces only given out sparingly, students go though the process of getting more information. How does one get more puzzle pieces and what is the interpretive process? Experience with this exercise demonstrates how students can sketch out an incredibly accurate conception of the "big picture", despite not having all the puzzle pieces. The goal of this talk is to give a complete tool kit to perform as a comprehensive lesson plan. Guiding questions and copies of lesson plans and materials are supplied for this exercise.

  15. Storage Technology: Present and Future.

    ERIC Educational Resources Information Center

    Goldstein, Charles M.

    1984-01-01

    Reviews terminology inherent in discussing microcomputer storage technologies and addresses aspects of magnetic storage and present and near-future technologies, including floppy disks, Winchester and removable hard disks, optical digital disks, optical video disks, (audio) compact disks, perpendicular magnetic recording, and erasable optical…

  16. Storage Technology: Present and Future.

    ERIC Educational Resources Information Center

    Goldstein, Charles M.

    1984-01-01

    Reviews terminology inherent in discussing microcomputer storage technologies and addresses aspects of magnetic storage and present and near-future technologies, including floppy disks, Winchester and removable hard disks, optical digital disks, optical video disks, (audio) compact disks, perpendicular magnetic recording, and erasable optical…

  17. Five-membered rings as diazo components in optical data storage devices: an ab initio investigation of the lowest singlet excitation energies

    NASA Astrophysics Data System (ADS)

    Åstrand, Per-Olof; Sommer-Larsen, Peter; Hvilsted, Søren; Ramanujam, P. S.; Bak, Keld L.; Sauer, Stephan P. A.

    2000-07-01

    The two lowest singlet excitation energies of 18 azo dyes have been studied by ab initio quantum-chemical methods within the second-order polarization propagator approximation (SOPPA). Various combinations of five-membered rings (furan, thiophene, pyrrole, oxazole, thiazole, and imidazole) have been investigated as diazo components for a potential use in optical data storage materials. It is found that the diazo compounds with two heterocyclic five-membered rings have π→π ∗ excitation energies corresponding to laser wavelengths in the region 450-500 nm whereas one five-membered ring and a phenyl group as diazo components results in wavelengths in the region 400-435 nm.

  18. Coaxial random-access reading in multilayered optical data storage systems using a pair of counter-propagating pulse-shaped spatial solitons

    NASA Astrophysics Data System (ADS)

    Hisaka, Masaki

    2017-07-01

    Coaxial random-access reading in multilayered optical data storage using a pair of counter-propagating pulse-shaped spatial solitons was experimentally investigated. Counter-propagating second-harmonic spatial solitons, which are formed by focusing titanium sapphire pulsed lasers, induced nonlinear collision and determined the depth readout address in a strontium barium niobate crystal. The nonlinear interaction between the collision and the locally-reversed crystal domains, which represents single-bit data, changed the spectrum and intensity of the transmitted second-harmonic beam. Coaxial random-access reading associated with the spatial soliton of the multilayered bit datum was demonstrated by scanning collision points along the direction of the depth.

  19. External insulation systems for cryogenic storage systems. Volume 1: Optical properties of Kapton and report of process variable study

    NASA Technical Reports Server (NTRS)

    Frank, A. M.

    1974-01-01

    Investigations are conducted into the optical properties of the glass and Kapton substrate materials, and three variables were chosen: deposition rate, sputter gas pressure, and film contamination time. Substrate tests have shown that fabrication of an dielectric broadband reflector would require an extremely complex and expensive filter design.

  20. The Computational Complexity of the Kakuro Puzzle, Revisited

    NASA Astrophysics Data System (ADS)

    Ruepp, Oliver; Holzer, Markus

    We present a new proof of NP-completeness for the problem of solving instances of the Japanese pencil puzzle Kakuro (also known as Cross-Sum). While the NP-completeness of Kakuro puzzles has been shown before [T. Seta. The complexity of CROSS SUM. IPSJ SIG Notes, AL-84:51-58, 2002], there are still two interesting aspects to our proof: we show NP-completeness for a new variant of Kakuro that has not been investigated before and thus improves the aforementioned result. Moreover some parts of the proof have been generated automatically, using an interesting technique involving SAT solvers.

  1. Finding optimal solutions to the twenty-four puzzle

    SciTech Connect

    Korf, R.E.; Taylor, L.A.

    1996-12-31

    We have found the first optimal solutions to random instances of the Twenty-Four Puzzle, the 5 x 5 version of the well-known sliding-tile puzzles. Our new contribution to this problem is a more powerful admissible heuristic function. We present a general theory for the automatic discovery of such heuristics, which is based on considering multiple subgoals simultaneously. In addition, we apply a technique for pruning duplicate nodes in depth-first search using a finite-state machine. Finally, we observe that as heuristic search problems are scaled up, more powerful heuristic functions become both necessary and cost-effective.

  2. The puzzle of Freud's puzzle analogy: Reviving a struggle with doubt and conviction in Freud's Moses and monotheism.

    PubMed

    Blass, Rachel B

    2003-06-01

    In this paper the author points to a puzzle raised by Freud's contradictory use of an analogy of a jigsaw puzzle. She shows how, through the attempt to resolve this puzzle, meanings and implications of Freud's difficult struggle with his search for truth in Moses and monotheism come alive, both in Freud's writing and in the author herself. Central to this struggle is an encounter with the sources of doubt and conviction that ultimately allows one to embrace ideas experienced as true, although they are not demonstrable evidentially. The paper sheds light on the importance of Moses and monotheism as a theoretical text that reflects on developments in Freud's thinking on truth, and the possibility, dangers and inherent difficulties of grasping it.

  3. Crossword puzzles: self-learning tool in pharmacology.

    PubMed

    Gaikwad, Nitin; Tankhiwale, Suresh

    2012-12-01

    Students of the second professional MBBS course of the Indian medical curriculum (II MBBS) perceive pharmacology as a 'Volatile Subject' because they often find it difficult to remember and recall drug names. We evaluated the usefulness of crossword puzzles as a self-learning tool to help pharmacology students to remember drug names. We also measured the students' satisfaction with this learning method. This was an open-label randomized, two-arm intervention study, conducted with II MBBS students (n = 70), randomly selected and assigned to two groups A (n = 35) and B (n = 35). Two self-learning modules containing crossword puzzles with antihypertensive and antiepileptic drug terms were prepared and pre-validated. Hard copies of both crossword puzzles were administered to Group A (Intervention group) on two different occasions. One hour was allotted to solve a puzzle. Students were allowed to refer to their textbooks. Group B (Control group) underwent the self-learning module without the crossword puzzles. In both groups, pre- and post-test knowledge was assessed. Students' perceptions of the crossword puzzles were assessed using a pre-validated 10-item questionnaire. Responses to items 1-8 were recorded using a 5-point Likert scale. Responses to item 9 were recorded on a 10-point rating scale while item 10 was an open-ended question. The crossword completion index was 92.86 %. In group A, the average pre-test score was 6.09 whereas the average post-test score was 12.87 (p < 0.05). In group B, average pre- and post-test scores were 6.03 and 9.74, respectively. A significant difference (p < 0.001) was observed between the post-test scores of the two groups. The absolute learning gain was 33.9 % in Group A and 18.55 % in Group B. The response rate for the questionnaire was 100 %. Of the students, 71.43 % strongly agreed that crossword puzzles enhanced their knowledge of antihypertensive and antiepileptic drugs and were helpful for remembering and

  4. Heavy quarkonium: progress, puzzles, and opportunities

    NASA Astrophysics Data System (ADS)

    Brambilla, N.; Eidelman, S.; Heltsley, B. K.; Vogt, R.; Bodwin, G. T.; Eichten, E.; Frawley, A. D.; Meyer, A. B.; Mitchell, R. E.; Papadimitriou, V.; Petreczky, P.; Petrov, A. A.; Robbe, P.; Vairo, A.; Andronic, A.; Arnaldi, R.; Artoisenet, P.; Bali, G.; Bertolin, A.; Bettoni, D.; Brodzicka, J.; Bruno, G. E.; Caldwell, A.; Catmore, J.; Chang, C.-H.; Chao, K.-T.; Chudakov, E.; Cortese, P.; Crochet, P.; Drutskoy, A.; Ellwanger, U.; Faccioli, P.; Gabareen Mokhtar, A.; Garcia i Tormo, X.; Hanhart, C.; Harris, F. A.; Kaplan, D. M.; Klein, S. R.; Kowalski, H.; Lansberg, J.-P.; Levichev, E.; Lombardo, V.; Lourenço, C.; Maltoni, F.; Mocsy, A.; Mussa, R.; Navarra, F. S.; Negrini, M.; Nielsen, M.; Olsen, S. L.; Pakhlov, P.; Pakhlova, G.; Peters, K.; Polosa, A. D.; Qian, W.; Qiu, J.-W.; Rong, G.; Sanchis-Lozano, M. A.; Scomparin, E.; Senger, P.; Simon, F.; Stracka, S.; Sumino, Y.; Voloshin, M.; Weiss, C.; Wöhri, H. K.; Yuan, C.-Z.

    2011-02-01

    A golden age for heavy-quarkonium physics dawned a decade ago, initiated by the confluence of exciting advances in quantum chromodynamics (QCD) and an explosion of related experimental activity. The early years of this period were chronicled in the Quarkonium Working Group (QWG) CERN Yellow Report (YR) in 2004, which presented a comprehensive review of the status of the field at that time and provided specific recommendations for further progress. However, the broad spectrum of subsequent breakthroughs, surprises, and continuing puzzles could only be partially anticipated. Since the release of the YR, the BESII program concluded only to give birth to BESIII; the B-factories and CLEO-c flourished; quarkonium production and polarization measurements at HERA and the Tevatron matured; and heavy-ion collisions at RHIC have opened a window on the deconfinement regime. All these experiments leave legacies of quality, precision, and unsolved mysteries for quarkonium physics, and therefore beg for continuing investigations at BESIII, the LHC, RHIC, FAIR, the Super Flavor and/or Tau-Charm factories, JLab, the ILC, and beyond. The list of newly found conventional states expanded to include h c (1 P), χ c2(2 P), Bc+, and η b (1 S). In addition, the unexpected and still-fascinating X(3872) has been joined by more than a dozen other charmonium- and bottomonium-like " XYZ" states that appear to lie outside the quark model. Many of these still need experimental confirmation. The plethora of new states unleashed a flood of theoretical investigations into new forms of matter such as quark-gluon hybrids, mesonic molecules, and tetraquarks. Measurements of the spectroscopy, decays, production, and in-medium behavior of cbar{c}, bbar{b}, and bbar{c} bound states have been shown to validate some theoretical approaches to QCD and highlight lack of quantitative success for others. Lattice QCD has grown from a tool with computational possibilities to an industrial-strength effort now

  5. Technical report: effects of PUVA treatment on the optical properties of blood/tissue storage bags during extracorporeal photochemotherapy.

    PubMed

    Keskin, Ali Umit

    2007-10-01

    Extracorporeal photochemotherapy (photopheresis, ECP) is a novel therapeutic method for patients who do not respond to immunosuppressive medications, and gaining interest in the treatment of Graft-vs-Host Disease. This paper is focused on the optical transmission properties of plastic bags which can be used in an independent (off-line) method of ECP, and reports the results of spectral measurements on various bags of different chemical compositions, with and without PUVA treatment. Regarding their higher and more uniform UVA transmission values, FEP based bags perform superior to the others. Considering its UVB absorption and UVA transmission properties, the EVA bag is a good choice, while Polyimide Kapton-FEP plastic film should not be considered for use in ECP. PUVA treatment of blood bags may affect their optical behaviour, and causes reduction of transmission of the material in UV range of the spectrum.

  6. Improving the precision of linear optics measurements based on turn-by-turn beam position monitor data after a pulsed excitation in lepton storage rings

    NASA Astrophysics Data System (ADS)

    Malina, L.; Coello de Portugal, J.; Persson, T.; Skowroński, P. K.; Tomás, R.; Franchi, A.; Liuzzo, S.

    2017-08-01

    Beam optics control is of critical importance for machine performance and protection. Nowadays, turn-by-turn (TbT) beam position monitor (BPM) data are increasingly exploited as they allow for fast and simultaneous measurement of various optics quantities. Nevertheless, so far the best documented uncertainty of measured β -functions is of about 10‰ rms. In this paper we compare the β -functions of the ESRF storage ring measured from two different TbT techniques—the N-BPM and the Amplitude methods—with the ones inferred from a measurement of the orbit response matrix (ORM). We show how to improve the precision of TbT techniques by refining the Fourier transform of TbT data with properly chosen excitation amplitude. The precision of the N-BPM method is further improved by refining the phase advance measurement. This represents a step forward compared to standard TbT measurements. First experimental results showing the precision of β -functions pushed down to 4‰ both in TbT and ORM techniques are reported and commented.

  7. Synthesis of novel fluorene-based two-photon absorbing molecules and their applications in optical data storage, microfabrication, and stimulated emission depletion

    NASA Astrophysics Data System (ADS)

    Yanez, Ciceron

    2009-12-01

    Two-photon absorption (2PA) has been used for a number of scientific and technological applications, exploiting the fact that the 2PA probability is directly proportional to the square of the incident light intensity (while one-photon absorption bears a linear relation to the incident light intensity). This intrinsic property of 2PA leads to 3D spatial localization, important in fields such as optical data storage, fluorescence microscopy, and 3D microfabrication. The spatial confinement that 2PA enables has been used to induce photochemical and photophysical events in increasingly smaller volumes and allowed nonlinear, 2PA-based, technologies to reach sub-diffraction limit resolutions. The primary focus of this dissertation is the development of novel, efficient 2PA, fluorene-based molecules to be used either as photoacid generators (PAGs) or fluorophores. A second aim is to develop more effective methods of synthesizing these compounds. As a third and final objective, the new molecules were used to develop a write-once-read many (WORM) optical data storage system, and stimulated emission depletion probes for bioimaging. In Chapter I, the microwave-assisted synthesis of triarylsulfonium salt photoacid generators (PAGs) from their diphenyliodonium counterparts is reported. The microwave-assisted synthesis of these novel sulfonium salts afforded reaction times 90 to 420 times faster than conventional thermal conditions, with photoacid quantum yields of new sulfonium PAGs ranging from 0.01 to 0.4. These PAGs were used to develop a fluorescence readout-based, nonlinear three-dimensional (3D) optical data storage system (Chapter II). In this system, writing was achieved by acid generation upon two-photon absorption (2PA) of a PAG (at 710 or 730 nm). Readout was then performed by interrogating two-photon absorbing dyes, after protonation, at 860 nm. Two-photon recording and readout of voxels was demonstrated in five and eight consecutive, crosstalk-free layers within a

  8. Teaching Proofs and Algorithms in Discrete Mathematics with Online Visual Logic Puzzles

    ERIC Educational Resources Information Center

    Cigas, John; Hsin, Wen-Jung

    2005-01-01

    Visual logic puzzles provide a fertile environment for teaching multiple topics in discrete mathematics. Many puzzles can be solved by the repeated application of a small, finite set of strategies. Explicitly reasoning from a strategy to a new puzzle state illustrates theorems, proofs, and logic principles. These provide valuable, concrete…

  9. A Geometric Puzzle That Leads To Fibonacci Sequences.

    ERIC Educational Resources Information Center

    Rulf, Benjamin

    1998-01-01

    Illustrates how mathematicians work and do mathematical research through the use of a puzzle. Demonstrates how general rules, then theorems develop from special cases. This approach may be used as a research project in high school classrooms or math club settings with the teacher helping to formulate questions, set goals, and avoid becoming…

  10. The Use of Word Puzzles in Teaching English

    ERIC Educational Resources Information Center

    Ridout, Ronald

    1977-01-01

    Word puzzles can be useful in FL teaching. They provide motivation. But they should be limited by the learner's linguistic competence, and should be carefully designed, with clear information, so as to create a high probability of successful solution. Method is discussed, using 3 examples. (IFS/WGA)

  11. Crossword Puzzles as a Learning Tool for Vocabulary Development

    ERIC Educational Resources Information Center

    Orawiwatnakul, Wiwat

    2013-01-01

    Introduction: Since vocabulary is a key basis on which reading achievement depends, various vocabulary acquisition techniques have become pivotal. Among the many teaching approaches, traditional or otherwise, the use of crossword puzzles seems to offer potential and a solution for the problem of learning vocabulary. Method: This study was…

  12. To Txt or Not to Txt: That's the Puzzle

    ERIC Educational Resources Information Center

    Goh, Tiong-Thye; Hooper, Val

    2007-01-01

    This paper describes the potential use of a mobile phone Short Message Service (SMS) crossword puzzle system to promote interaction through learning activities in a large classroom environment. While personal response systems (PRS) have been used in the classroom environment to foster interaction, it is not an ideal tool with respect to cost and…

  13. Unraveling "Braid": Puzzle Games and Storytelling in the Imperative Mood

    ERIC Educational Resources Information Center

    Arnott, Luke

    2012-01-01

    "Unraveling Braid" analyzes how unconventional, non-linear narrative fiction can help explain the ways in which video games signify. Specifically, this essay looks at the links between the semiotic features of Jonathan Blow's 2008 puzzle-platform video game Braid and similar elements in Georges Perec's 1978 novel "Life A User's Manual," as well as…

  14. To Txt or Not to Txt: That's the Puzzle

    ERIC Educational Resources Information Center

    Goh, Tiong-Thye; Hooper, Val

    2007-01-01

    This paper describes the potential use of a mobile phone Short Message Service (SMS) crossword puzzle system to promote interaction through learning activities in a large classroom environment. While personal response systems (PRS) have been used in the classroom environment to foster interaction, it is not an ideal tool with respect to cost and…

  15. The Potential of Crossword Puzzles in Aiding English Language Learners

    ERIC Educational Resources Information Center

    Merkel, Warren

    2016-01-01

    In an academic environment, teachers utilize crossword puzzles to help students learn or remember terminology. Outside the classroom, typically in daily newspapers, crosswords aid in vocabulary development, used as a learning tool, a leisure activity, or both. However, both the content and the grid structure of the crosswords in these two…

  16. Using Building-Block Puzzles to Practice Drawing Organic Mechanisms

    ERIC Educational Resources Information Center

    Erdik, Ender

    2005-01-01

    A study uses a thought-provoking, pencil-and-paper activity to aid students in writing organic reaction mechanisms. Organic and functional groups that constitute the formulas of organic and inorganic reactants, ionic intermediates, and products are presented as building blocks, which must be placed correctly in a given puzzle so that they bind…

  17. A Jigsaw Puzzle Approach To Learning History in Introductory Psychology.

    ERIC Educational Resources Information Center

    Krauss, Judith

    1999-01-01

    Believes that it may be daunting for some students to learn about the history of psychology. Describes a teaching strategy that uses jigsaw puzzles to teach about the historical terms of structuralism, functionalism, and gestalt psychology. Finds that students performed better on test questions related to these three concepts after using this…

  18. The Potential of Crossword Puzzles in Aiding English Language Learners

    ERIC Educational Resources Information Center

    Merkel, Warren

    2016-01-01

    In an academic environment, teachers utilize crossword puzzles to help students learn or remember terminology. Outside the classroom, typically in daily newspapers, crosswords aid in vocabulary development, used as a learning tool, a leisure activity, or both. However, both the content and the grid structure of the crosswords in these two…

  19. Understanding the puzzle of 'well-characterized biotechnology products'.

    PubMed

    Sadick, Michael

    2002-06-01

    The concept of a 'well-characterized biotechnology product' is akin to assembling a jigsaw puzzle. Each of the analytical pieces must be assembled to provide a clearly, orthogonally defined picture that addresses completely the physicochemical, biological and pharmacological attributes that fully characterize the molecule.

  20. Puzzle Them First! Motivating Adolescent Readers with Question-Finding

    ERIC Educational Resources Information Center

    Ciardiello, A. Vincent

    2007-01-01

    In this book, the author suggests that to truly learn, students should be puzzled about new knowledge. Question-finding, the unique strategy described in the book, fosters this learning by leading adolescent students to probe the multiple meanings of text and ask challenging, open-ended questions. Focus units illustrate how teachers can use…

  1. Tangram Puzzles: Focus on Search Terms, Descriptors, and Subject Headings.

    ERIC Educational Resources Information Center

    School Library Media Activities Monthly, 1993

    1993-01-01

    Describes the history of tangrams and their use as mathematical puzzles and explains how they can be adapted for library media specialists to use for developing subject headings on a particular topic. An example is given; and 28 resources on tangrams are listed, including books, nonprint materials, and addresses. (LRW)

  2. Unraveling "Braid": Puzzle Games and Storytelling in the Imperative Mood

    ERIC Educational Resources Information Center

    Arnott, Luke

    2012-01-01

    "Unraveling Braid" analyzes how unconventional, non-linear narrative fiction can help explain the ways in which video games signify. Specifically, this essay looks at the links between the semiotic features of Jonathan Blow's 2008 puzzle-platform video game Braid and similar elements in Georges Perec's 1978 novel "Life A User's Manual," as well as…

  3. OLYMPUS and the proton form factor puzzle

    NASA Astrophysics Data System (ADS)

    Ice, Lauren; Alarcon, Ricardo; Olympus Collaboration

    2012-02-01

    Recent measurements of the proton electric to magnetic form factor ratio using polarization techniques reveal a large discrepancy with measurements found using the Rosenbluth separation technique. It has been proposed that this discrepancy is due to a non-negligible multiple photon exchange contribution in the electron-proton elastic scattering cross section. The OLYMPUS experiment will measure the multiple photon exchange contribution by finding the cross section ratio of positron-proton to electron-proton scattering within 1%. The experiment will be carried out at the DESY laboratory in Hamburg Germany using the electron and positron storage ring DORIS and an internal unpolarized hydrogen gas target. The scattered particles will be detected using the Bates Large Acceptance Spectrometer Toroid (BLAST).

  4. Entanglement, teleportation, and single-photon storage with two-level atoms inside an optical parametric oscillator

    SciTech Connect

    Rice, Perry R.

    2005-07-01

    I consider several interesting aspects of a new light source, a two-level atom, or N two-level atoms inside an optical parametric oscillator. I find that in the weak driving limit, detection of a transmitted or fluorescent photon generates a highly entangled state of the atom and the cavity. This entanglement can be used with beam splitters to create more complex quantum states and implement teleportation protocols. Also, one can store a single photon in the atoms, along the lines of recent slow and stopped light proposals and experiments.

  5. Update On the Puzzling Boyajian's Star

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-09-01

    Photometric time series for a neighboring star thats 25 NNW of Boyajians Star. No significant long-term dimming is seen which constrains the size of potential material obscuring Boyajians Star. [Wright et al. 2016/Benjamin Montet]Whats causing the mysterious light-curve dips of the so-called alien megastructure star, Boyajians Star? A recent study analyzes a variety of possible explanations to determine which ones are the most plausible.An Unusual Light CurveEarlier this year, astronomer Tabetha Boyajian reported on the unusual light curve of the star KIC 8462852. This star, now nicknamed Tabbys Star or Boyajians Star, showsunusual dips on day-long timescales that are too large to be explained by planet transits or similar phenomena.In addition to these short dips in luminosity, recent observations have also indicated that the star has faded by roughly 20% over the past hundred years. What could be causing both the short-term dips in the stars light and the long-term dimming over a century?Could the dimming be caused by an alien megastructure built by an extraterrestrial civilization? The authors find that a spherical structure is very unlikely. [Danielle Futselaar/SETI International]Alien Megastructures? Or Another Explanation?Boyajians Star was vaulted into the media spotlight when astronomer Jason Wright (Pennsylvania State University and University of California, Berkeley) proposed that its unusual light curve could potentially be explained by a surrounding megastructure built by an extraterrestrial civilization.Now Wright is back with co-author Steinn Sigurdsson (Pennsylvania State University). In a new study, Wright and Sigurdsson analyze an extensive list of explanations for the puzzling apparent behavior of Boyajians Star, based on our latest knowledge about this strange object.The Realm of PossibilitiesHere are just a few possible causes of Boyajians Stars dimming, as well as the authors assessment of their plausibility. For the full list, see the authors

  6. Study of thermal effects and optical properties of an innovative absorber in integrated collector storage solar water heater

    NASA Astrophysics Data System (ADS)

    Taheri, Yaser; Alimardani, Kazem; Ziapour, Behrooz M.

    2015-10-01

    Solar passive water heaters are potential candidates for enhanced heat transfer. Solar water heaters with an integrated water tank and with the low temperature energy resource are used as the simplest and cheapest recipient devices of the solar energy for heating and supplying hot water in the buildings. The solar thermal performances of one primitive absorber were determined by using both the experimental and the simulation model of it. All materials applied for absorber such as the cover glass, the black colored sands and the V shaped galvanized plate were submerged into the water. The water storage tank was manufactured from galvanized sheet of 0.0015 m in thickness and the effective area of the collector was 0.67 m2. The absorber was installed on a compact solar water heater. The constructed flat-plate collectors were tested outdoors. However the simulation results showed that the absorbers operated near to the gray materials and all experimental results showed that the thermal efficiencies of the collector are over than 70 %.

  7. Emerging Network Storage Management Standards for Intelligent Data Storage Subsystems

    NASA Technical Reports Server (NTRS)

    Podio, Fernando; Vollrath, William; Williams, Joel; Kobler, Ben; Crouse, Don

    1998-01-01

    This paper discusses the need for intelligent storage devices and subsystems that can provide data integrity metadata, the content of the existing data integrity standard for optical disks and techniques and metadata to verify stored data on optical tapes developed by the Association for Information and Image Management (AIIM) Optical Tape Committee.

  8. Emerging Network Storage Management Standards for Intelligent Data Storage Subsystems

    NASA Technical Reports Server (NTRS)

    Podio, Fernando; Vollrath, William; Williams, Joel; Kobler, Ben; Crouse, Don

    1998-01-01

    This paper discusses the need for intelligent storage devices and subsystems that can provide data integrity metadata, the content of the existing data integrity standard for optical disks and techniques and metadata to verify stored data on optical tapes developed by the Association for Information and Image Management (AIIM) Optical Tape Committee.

  9. Evaluation of the heat-storage capability of shallow aquifers using active heat tracer tests and Fiber-Optics Distributed-Temperature-Sensing

    NASA Astrophysics Data System (ADS)

    Suibert Oskar Seibertz, Klodwig; Chirila, Marian Andrei; Bumberger, Jan; Dietrich, Peter; Vienken, Thomas

    2015-04-01

    In the course of the energy transition, geothermal energy storage and heat generation and cooling have proven to be environmental friendly alternatives to conventional energy. However, to ensure sustain usage, the heat transport behavior of aquifers and its distribution has to be studied. A tool to achieve this is the active heat tracer test, eg. Leaf et al. (2012). If active heat tracer tests are combined with in aquifer heat testing via electric heating-cables, eg. Liu et al. (2013), it is possible to observe heat transport and temperature signal decay without disturbing the original pressure field within the aquifer. In this field study a two channel High-Resolution-Fiber-Optic-Distributed-Temperature-Sensing and Pt100 were used to measure temperature signals within in two wells of 1.4 m distance, where the temperature difference was generated using a self regulating heating cable in the upstream well. High resolution Distributed-Temperature-Sensing measurements were achieved by coiling the fiber around screened plastic tubes. The upstream well was also used to observe heating (Δ Tmax approx. 24K) and temperature signal decay, while the downstream well was used to observe heat transport between both wells. The data was analyzed and compared to thermal conductivity of soil samples and Direct-Push (DP) Electrical-Conductivity-Logging and DP Hydraulic-Profiling results. The results show good agreement between DP data and temperature measurements proving the active heat tracer test is a suitable tool for providing reliable information on aquifer heat-storage capability. References Leaf, A.T., Hart, D.J., Bahr, J.M.: Active Thermal Tracer Tests for Improved Hydrostratigraphic Characterization. Ground Water, vol. 50, 2012 Liu, G., Knobbe, S., Butler, J.J.Jr.: Resolving centimeter-scale flows in aquifers and their hydrostratigraphic controls. Geophysical Research Letters, vol. 40, 2013

  10. Storage and retrieval of SNOP-coded pathologic diagnoses using offsite computing and optical character recognizing systems.

    PubMed

    Cechner, R L; Carter, J R

    1976-05-01

    A computerized cross-reference system for retrieving autopsy and surgical pathology cases on the basis of case number or diagnosis has been implemented. The system achieves economy and flexibility by using offsite computer service bureaus for job production, eliminating the need for expensive onsite equipment. Coded diagnoses may be typed using the OCR (Optical Character Recognition) font simultaneously with or separately from the clinical documentation. The flexibility of new OCR equipment permits production of machine-readable code sheets with an ordinary pencil and completely eliminates the need for typing. The system produces year-to-date books that list all diagnoses, on an accumulating basis, in alphabetic order by SNOP* topology, morphology, etiology and function, and will be compatible with SNOMed. Because all data are stored on magnetic tape, they may be manipulated and retrieved as desired through user programming. The initial setup cost was dollar 1,000 for programming and testing, and production runs and all report printing cost about dollar 1,000 per year (autopsies and surgical pathology cases), which is about 1.1 cents per diagnosis.

  11. Puzzles about 1/8 magic doping in cuprate

    NASA Astrophysics Data System (ADS)

    Feng, D. L.; Shen, Z.-X.; Zhou, X. J.; Shen, K. M.; Lu, D. H.; Marel, D. V. D.

    2006-01-01

    We discuss the puzzles surrounding the interpretation of the 1/8 anomaly in cuprates, highlighting the tension between the real and reciprocal space ways to look at the problem. This issue is relevant to the current discussion on the nature of charge ordering in the form of ‘stripe’ and ‘checker-board’ as derived from neutron and STM experiments. A resolution of this tension is important to fully understand the electronic structure.

  12. High-energy cosmic neutrino puzzle: a review.

    PubMed

    Ahlers, Markus; Halzen, Francis

    2015-12-01

    We appraise the status of high-energy neutrino astronomy and summarize the observations that define the 'IceCube puzzle.' The observations are closing in on the source candidates that may contribute to the observation. We highlight the potential of multi-messenger analysis to assist in the identification of the sources. We also give a brief overview of future search strategies that include the realistic possibility of constructing a next-generation detector larger by one order of magnitude in volume.

  13. Tetsuo Nozoe's Autograph Books: poems, puzzles and playfulness.

    PubMed

    Seeman, Jeffrey I

    2015-02-01

    The Nozoe Autograph Books contain entries from, literally, around the world of organic chemistry. Many of the inscriptions showed the poetic or even musical side of their signees. This Essay presents a diverse selection of the poetic entries of the autograph books, starting with a musical puzzle. This Essay and the interactive website that accompanies the Nozoe Autograph Book project are available free-access for at least a three-year period at http://www.tcr.wiley-vch.de/nozoe.

  14. Food puzzles for cats: Feeding for physical and emotional wellbeing.

    PubMed

    Dantas, Leticia Ms; Delgado, Mikel M; Johnson, Ingrid; Buffington, Ca Tony

    2016-09-01

    Many pet cats are kept indoors for a variety of reasons (eg, safety, health, avoidance of wildlife predation) in conditions that are perhaps the least natural to them. Indoor housing has been associated with health issues, such as chronic lower urinary tract signs, and development of problem behaviors, which can cause weakening of the human-animal bond and lead to euthanasia of the cat. Environmental enrichment may mitigate the effects of these problems and one approach is to take advantage of cats' natural instinct to work for their food. In this article we aim to equip veterinary professionals with the tools to assist clients in the use of food puzzles for their cats as a way to support feline physical health and emotional wellbeing. We outline different types of food puzzles, and explain how to introduce them to cats and how to troubleshoot challenges with their use. The effect of food puzzles on cats is a relatively new area of study, so as well as reviewing the existing empirical evidence, we provide case studies from our veterinary and behavioral practices showing health and behavioral benefits resulting from their use. © The Author(s) 2016.

  15. 3D satellite puzzles for young and old kids

    NASA Astrophysics Data System (ADS)

    Biondi, Riccardo; Galoforo, Germana

    2017-04-01

    The Italian Space Agency (ASI) is active in outreach willing to increase the interest of young generations and general public toward the space activities. ASI proposes educational programmes for supporting and encouraging the development of European society based on knowledge, inspiring and motivating the young generations. One of the initiatives promoted by ASI on this regards is the 3D satellite puzzles. The idea was born in 2007 from the will to conceive an educational product for promoting and explaining to students the small all-Italian mission AGILE (Astrorivelatore Gamma ad Immagini ultra Leggero) thought as a tool for students aged 8-13. Working with this slot of students is very productive in terms of the imprints left on the kids, in fact it is useful to produce things they can use, touch and play with, with an active approach instead of a passive one. Therefore it was decided to produce something that kids could build and use at home with their parents or friends, or all together at school with teachers and mates. Other puzzles followed AGILE, one about the COSMO-SkyMED satellites about Earth Observation and also a broader one of the International Space Station. During these 10 years the puzzles were mostly used as outreach tools for school children, but they surprisingly received a great success also within older generations. So far the 3D puzzles have been printed in more than 10 thousand copies and distributed for free to students of hundreds of schools in Italy, and to the general public through science associations, planetaria and museums. Recently they have been used also during special events such as the international Geoscience Communication School (as best practice outreach tool), the EXPO 2015 and the European Researcheŕs Night at the Parlamentarium in Brussels 2016. While the students are building the puzzles, the tutor explains them the different components that they are assembling, what the importance of the satellite is and how it works

  16. Crossword Puzzles as a Tool to Enhance Learning About Anti-Ulcer Agents

    PubMed Central

    Lynch, Launa M. J.; Macias-Moriarity, Lilia Z.

    2010-01-01

    Objective To design, implement, and evaluate the use of crossword puzzles as a low-stakes educational tool for enhancing learning about anti-ulcer agents. Design Crossword puzzles were created using a free Internet resource and administered to students during 3 consecutive lectures covering the pharmacology and medicinal chemistry of anti-ulcer agents. Student perceptions of the crossword puzzle were examined using an 8-item survey instrument. Assessment Over 90% of students indicated that crossword puzzles enhanced their learning, oriented them to the important topics, and served as good reviews of the lecture material. Conclusion Students perceived that crossword puzzles enhanced their learning of anti-ulcer agents. Use of crossword puzzles provides a simple and creative way to incorporate active learning into pharmacy classroom instruction. PMID:21088722

  17. Strategies and correlates of jigsaw puzzle and visuospatial performance by persons with Prader-Willi syndrome.

    PubMed

    Verdine, Brian N; Troseth, Georgene L; Hodapp, Robert M; Dykens, Elisabeth M

    2008-09-01

    Some individuals with Prader-Willi syndrome exhibit strengths in solving jigsaw puzzles. We compared visuospatial ability and jigsaw puzzle performance and strategies of 26 persons with Prader-Willi syndrome and 26 MA-matched typically developing controls. Individuals with Prader-Willi syndrome relied on piece shape. Those in the control group used a different, picture-focused strategy. Individuals with Prader-Willi syndrome performed better than did the control group on an achromatic interlocking puzzle, whereas scores on puzzles with pictures (interlocking or noninterlocking) did not differ. Visuospatial scores related to performance on all puzzles in the control group and on the noninterlocking puzzle in the Prader-Willi syndrome group. The most proficient jigsaw puzzlers with Prader-Willi syndrome tended to be older and have shape-based strategies.

  18. Optical Disks.

    ERIC Educational Resources Information Center

    Gale, John C.; And Others

    1985-01-01

    This four-article section focuses on information storage capacity of the optical disk covering the information workstation (uses microcomputer, optical disk, compact disc to provide reference information, information content, work product support); use of laser videodisc technology for dissemination of agricultural information; encoding databases…

  19. Energy storage

    NASA Astrophysics Data System (ADS)

    Kaier, U.

    1981-04-01

    Developments in the area of energy storage are characterized, with respect to theory and laboratory, by an emergence of novel concepts and technologies for storing electric energy and heat. However, there are no new commercial devices on the market. New storage batteries as basis for a wider introduction of electric cars, and latent heat storage devices, as an aid for solar technology applications, with satisfactory performance standards are not yet commercially available. Devices for the intermediate storage of electric energy for solar electric-energy systems, and for satisfying peak-load current demands in the case of public utility companies are considered. In spite of many promising novel developments, there is yet no practical alternative to the lead-acid storage battery. Attention is given to central heat storage for systems transporting heat energy, small-scale heat storage installations, and large-scale technical energy-storage systems.

  20. Striped tertiary storage arrays

    NASA Technical Reports Server (NTRS)

    Drapeau, Ann L.

    1993-01-01

    Data stripping is a technique for increasing the throughput and reducing the response time of large access to a storage system. In striped magnetic or optical disk arrays, a single file is striped or interleaved across several disks; in a striped tape system, files are interleaved across tape cartridges. Because a striped file can be accessed by several disk drives or tape recorders in parallel, the sustained bandwidth to the file is greater than in non-striped systems, where access to the file are restricted to a single device. It is argued that applying striping to tertiary storage systems will provide needed performance and reliability benefits. The performance benefits of striping for applications using large tertiary storage systems is discussed. It will introduce commonly available tape drives and libraries, and discuss their performance limitations, especially focusing on the long latency of tape accesses. This section will also describe an event-driven tertiary storage array simulator that is being used to understand the best ways of configuring these storage arrays. The reliability problems of magnetic tape devices are discussed, and plans for modeling the overall reliability of striped tertiary storage arrays to identify the amount of error correction required are described. Finally, work being done by other members of the Sequoia group to address latency of accesses, optimizing tertiary storage arrays that perform mostly writes, and compression is discussed.

  1. Data storage technology comparisons

    NASA Technical Reports Server (NTRS)

    Katti, Romney R.

    1990-01-01

    The role of data storage and data storage technology is an integral, though conceptually often underestimated, portion of data processing technology. Data storage is important in the mass storage mode in which generated data is buffered for later use. But data storage technology is also important in the data flow mode when data are manipulated and hence required to flow between databases, datasets and processors. This latter mode is commonly associated with memory hierarchies which support computation. VLSI devices can reasonably be defined as electronic circuit devices such as channel and control electronics as well as highly integrated, solid-state devices that are fabricated using thin film deposition technology. VLSI devices in both capacities play an important role in data storage technology. In addition to random access memories (RAM), read-only memories (ROM), and other silicon-based variations such as PROM's, EPROM's, and EEPROM's, integrated devices find their way into a variety of memory technologies which offer significant performance advantages. These memory technologies include magnetic tape, magnetic disk, magneto-optic disk, and vertical Bloch line memory. In this paper, some comparison between selected technologies will be made to demonstrate why more than one memory technology exists today, based for example on access time and storage density at the active bit and system levels.

  2. ysteries, Puzzles, and Paradoxes in Quantum Mechanics. Proceedings

    SciTech Connect

    Rodolfo, B.

    1999-02-01

    These proceedings represent papers presented at the Mysteries, Puzzles, and Paradoxes in Quantum Mechanics Workshop held in Italy, in August 1998. The Workshop was devoted to recent experimental and theoretical advances such as new interference, effects, the quantum eraser, non{minus}disturbing and Schroedinger{minus}cat{minus}like states, experiments, EPR correlations, teleportation, superluminal effects, quantum information and computing, locality and causality, decoherence and measurement theory. Tachyonic information transfer was also discussed. There were 45 papers presented at the conference,out of which 2 have been abstracted for the Energy,Science and Technology database.(AIP)

  3. Toward a resolution of the proton size puzzle

    SciTech Connect

    Miller, G. A.; Thomas, A. W.; Carroll, J. D.; Rafelski, J.

    2011-08-15

    We show that off-mass-shell effects arising from the internal structure of the proton provide a new proton polarization mechanism in the Lamb shift, proportional to the lepton mass to the fourth power. This effect is capable of resolving the current puzzle regarding the difference in the proton radius extracted from muonic compared with electronic hydrogen experiments. These off-mass-shell effects could be probed in several other experiments. A significant ambiguity appearing in dispersion relation evaluations of the proton polarizability contribution to the Lamb shift is noted.

  4. The Puzzle of a Marble in a Spinning Pipe

    DTIC Science & Technology

    2015-05-01

    MAY 2015 2. REPORT TYPE 3. DATES COVERED 00-00-2015 to 00-00-2015 4. TITLE AND SUBTITLE The Puzzle of a Marble in a Spinning Pipe 5a. CONTRACT...Approved for public release; distribution unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT What trajectory does a marble follow if it is held...298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 Physics Education 50 (3) 279 1. Problem statement A marble is placed one-third of the length along a

  5. Optical Digital Image Storage System

    DTIC Science & Technology

    1991-03-18

    contrast’levels for each image wi’thout oprator in’tervention. Furher rese’arch and’investigation of thisand other ne - scannes in an operational...with a different set of parameters, the results would be different. It is also conceivable that rapid advances in evolutionary technologies such as...showed demonstrations were seemingly impressed and pleased at the prospect of rapid , accurate access to the files. Hence, in some cases, a conversion to

  6. Tiny bubbles challenge giant turbines: Three Gorges puzzle

    PubMed Central

    Li, Shengcai

    2015-01-01

    Since the birth of the first prototype of the modern reaction turbine, cavitation as conjectured by Euler in 1754 always presents as a challenge. Following his theory, the evolution of modern reaction (Francis and Kaplan) turbines has been completed by adding the final piece of the element ‘draft-tube’ that enables turbines to explore water energy at efficiencies of almost 100%. However, during the last two and a half centuries, with increasing unit capacity and specific speed, the problem of cavitation has been manifested and complicated by the draft-tube surges rather than being solved. Particularly, during the last 20 years, the fierce competition in the international market for extremely large turbines with compact design has encouraged the development of giant Francis turbines of 700–1000 MW. The first group (24 units) of such giant turbines of 700 MW each was installed in the Three Gorges project. Immediately after commission, a strange erosion phenomenon appeared on the guide vane of the machines that has puzzled professionals. From a multi-disciplinary analysis, this Three Gorges puzzle could reflect an unknown type of cavitation inception presumably triggered by turbulence production from the boundary-layer streak transitional process. It thus presents a fresh challenge not only to this old turbine industry, but also to the fundamental sciences. PMID:26442144

  7. Yet another possible explanation of the solar-neutrino puzzle

    SciTech Connect

    Kolb, E.W.; Turner, M.S.; Walker, T.P.

    1986-04-01

    Mikheyev and Smirnov have shown that the interactions of neutrinos with matter can result in the conversion of electron neutrinos produced in the center of the sun to muon neutrinos. Bethe has exploited this and has pointed out that the solar-neutrino puzzle can be resolved if the mass difference squared of the two neutrinos is m/sub 2//sup 2/ - m /sub 1//sup 2/ approx. = 6 x 10/sup -5/ eV/sup 2/, and the mixing angle satisfies sin theta/sub v/ > 0.0065. We discuss a qualitatively different solution to the solar-neutrino puzzle which requires 1.0 x 10/sup -8/ < (m/sub 2//sup 2/ - m/sub 1//sup 2/) (sin/sup 2/ 2theta/sub v//cos 2theta/sub v/) < 6.1 x 10/sup -8/ eV/sup 2/. Our solutions result in a much smaller flux of neutrinos from the p - p process than predicted by standard solar models, while Bethe's solution results in a flux of neutrinos from the p - process that is about the same as standard solar models.

  8. May heavy neutrinos solve underground and cosmic-ray puzzles?

    SciTech Connect

    Belotsky, K. M. Fargion, D. Khlopov, M. Yu. Konoplich, R. V.

    2008-01-15

    Primordial heavy neutrinos of the fourth generation might explain different astrophysical puzzles. The simplest fourth-neutrino scenario is consistent with known fourth-neutrino physics, cosmic ray antimatter, cosmic gamma fluxes, and positive signals in underground detectors for a very narrow neutrino mass window (46-47 GeV). However, accounting for the constraint of underground experiment CDMS prohibits solution of cosmic-ray puzzles in this scenario. We have analyzed extended heavy-neutrino models related to the clumpiness of neutrino density, new interactions in heavy-neutrino annihilation, neutrino asymmetry, and neutrino decay. We found that, in these models, the cosmic-ray imprint may fit the positive underground signals in DAMA/Nal experiment in the entire mass range 46-70 GeV allowed from uncertainties of electroweak parameters, while satisfaction of the CDMS constraint reduces the mass range to around 50 GeV, where all data can come to consent in the framework of the considered hypothesis.

  9. An ecological examination of rapport using a dyadic puzzle task.

    PubMed

    Grahe, Jon E; Sherman, Ryne A

    2007-10-01

    Previous studies have indicated that situational context impacts the rapport experience (e.g., F. J. Bernieri, J. S. Gillis, J. M. Davis, & J. E. Grahe, 1996; N. M. Puccinelli, L. Tickle-Degnen, & R. Rosenthal, 2003). The authors designed the present study to further document the behavioral and experiential predictors of dyadic rapport and to evaluate dyadic rapport experiences when contributions were required from both interactants. Participants (N = 60) were paired into dyads and instructed to complete children's puzzles. However, the dyadic members were restricted in how they could accomplish this task: Only one interactant was allowed to work on the puzzle and had to do so blindfolded, while the second interactant gave instructions. Results suggested that less attribution of responsibility to the worker and the instructor's experience of enjoyment and frustration were indicative of higher rapport. Other characteristics of dyads reporting higher dyadic rapport included difficulty completing the task and more communicative behavior. The results provide important information for the understanding of the dyadic experience of rapport.

  10. Tiny bubbles challenge giant turbines: Three Gorges puzzle.

    PubMed

    Li, Shengcai

    2015-10-06

    Since the birth of the first prototype of the modern reaction turbine, cavitation as conjectured by Euler in 1754 always presents as a challenge. Following his theory, the evolution of modern reaction (Francis and Kaplan) turbines has been completed by adding the final piece of the element 'draft-tube' that enables turbines to explore water energy at efficiencies of almost 100%. However, during the last two and a half centuries, with increasing unit capacity and specific speed, the problem of cavitation has been manifested and complicated by the draft-tube surges rather than being solved. Particularly, during the last 20 years, the fierce competition in the international market for extremely large turbines with compact design has encouraged the development of giant Francis turbines of 700-1000 MW. The first group (24 units) of such giant turbines of 700 MW each was installed in the Three Gorges project. Immediately after commission, a strange erosion phenomenon appeared on the guide vane of the machines that has puzzled professionals. From a multi-disciplinary analysis, this Three Gorges puzzle could reflect an unknown type of cavitation inception presumably triggered by turbulence production from the boundary-layer streak transitional process. It thus presents a fresh challenge not only to this old turbine industry, but also to the fundamental sciences.

  11. Three Puzzles in Galactic Extra-planar H I

    NASA Astrophysics Data System (ADS)

    Lockman, F. J.

    2012-09-01

    Many phenomena first detected in Galactic H i, such as high velocity clouds and gaseous warps, have now been detected and studied in nearby galaxies. Given this valuable perspective I examine three aspects of Galactic extra-planar gas that appear somewhat puzzling from our vantage in the Milky Way disk. I. Spiral galaxies have a rotation curve that decreases with distance above their mid-plane; where is the lagging halo in the Milky Way? II. Other systems show clear evidence for accretion of neutral gas; where is this gas in the Milky Way? III. Warps of the H i layer are common in the outskirts of disk galaxies; are we confident that we've correctly parameterized our own warp? The answers appear to be that lagging halo gas could well be present in the Galaxy but would be difficult to detect; that there is now solid evidence for the accretion of high-velocity H i clouds by the disk, though the details are still mysterious, and that the warp continues to baffle us, as it exhibits a puzzling morphology and kinematics.

  12. The puzzling unsolved mysteries of liquid water: Some recent progress

    NASA Astrophysics Data System (ADS)

    Stanley, H. E.; Kumar, P.; Xu, L.; Yan, Z.; Mazza, M. G.; Buldyrev, S. V.; Chen, S.-H.; Mallamace, F.

    2007-12-01

    Water is perhaps the most ubiquitous, and the most essential, of any molecule on earth. Indeed, it defies the imagination of even the most creative science fiction writer to picture what life would be like without water. Despite decades of research, however, water's puzzling properties are not understood and 63 anomalies that distinguish water from other liquids remain unsolved. We introduce some of these unsolved mysteries, and demonstrate recent progress in solving them. We present evidence from experiments and computer simulations supporting the hypothesis that water displays a special transition point (which is not unlike the “tipping point” immortalized by Malcolm Gladwell). The general idea is that when the liquid is near this “tipping point,” it suddenly separates into two distinct liquid phases. This concept of a new critical point is finding application to other liquids as well as water, such as silicon and silica. We also discuss related puzzles, such as the mysterious behavior of water near a protein.

  13. A Teacher's Ready-to-Use Packet of General Business Subjects Crossword Puzzles.

    ERIC Educational Resources Information Center

    Yacyk, Peter

    Eleven crossword puzzles, designed to give the student practice with the correct spelling and usage of those words needed to indicate his mastery of the concepts and understandings taught in business courses, are contained, with answer keys, in a teacher's packet. Any puzzle can be reproduced by ditto or by transparency for classroom use. There is…

  14. Strategies and Correlates of Jigsaw Puzzle and Visuospatial Performance by Persons with Prader-Willi Syndrome

    ERIC Educational Resources Information Center

    Verdine, Brian N.; Troseth, Georgene L.; Hodapp, Robert M.; Dykens, Elisabeth M.

    2008-01-01

    Some individuals with Prader-Willi syndrome exhibit strengths in solving jigsaw puzzles. We compared visuospatial ability and jigsaw puzzle performance and strategies of 26 persons with Prader-Willi syndrome and 26 MA-matched typically developing controls. Individuals with Prader-Willi syndrome relied on piece shape. Those in the control group…

  15. Using the Tower of Hanoi Puzzle to Infuse Your Mathematics Classroom with Computer Science Concepts

    ERIC Educational Resources Information Center

    Marzocchi, Alison S.

    2016-01-01

    This article suggests that logic puzzles, such as the well-known Tower of Hanoi puzzle, can be used to introduce computer science concepts to mathematics students of all ages. Mathematics teachers introduce their students to computer science concepts that are enacted spontaneously and subconsciously throughout the solution to the Tower of Hanoi…

  16. An Alternative Evaluation: Online Puzzle as a Course-End Activity

    ERIC Educational Resources Information Center

    Genç, Zülfü; Aydemir, Emrah

    2015-01-01

    Purpose: The purpose of this study is to determine whether the use of online puzzles in the instructional process has an effect on student achievement and learning retention. This study examined students ' perception and experiences on use of puzzle as an alternative evaluation tool. To achieve this aim, the following hypotheses were tested: using…

  17. Crossword Puzzle Makes It Fun: Introduce Green Manufacturing in Wood Technology Courses

    ERIC Educational Resources Information Center

    Iley, John L.; Hague, Doug

    2012-01-01

    Sustainable, or "green," manufacturing and its practices are becoming more and more a part of today's industry, including wood product manufacturing. This article provides introductory information on green manufacturing in wood technology and a crossword puzzle based on green manufacturing terms. The authors use the puzzle at the college level to…

  18. The King and Prisoner Puzzle: A Way of Introducing the Components of Logical Structures

    ERIC Educational Resources Information Center

    Roh, Kyeong Hah; Lee, Yong Hah; Tanner, Austin

    2016-01-01

    The purpose of this paper is to provide issues related to student understanding of logical components that arise when solving word problems. We designed a logic problem called the King and Prisoner Puzzle--a linguistically simple, yet logically challenging problem. In this paper, we describe various student solutions to the puzzle and discuss the…

  19. Strategies and Correlates of Jigsaw Puzzle and Visuospatial Performance by Persons with Prader-Willi Syndrome

    ERIC Educational Resources Information Center

    Verdine, Brian N.; Troseth, Georgene L.; Hodapp, Robert M.; Dykens, Elisabeth M.

    2008-01-01

    Some individuals with Prader-Willi syndrome exhibit strengths in solving jigsaw puzzles. We compared visuospatial ability and jigsaw puzzle performance and strategies of 26 persons with Prader-Willi syndrome and 26 MA-matched typically developing controls. Individuals with Prader-Willi syndrome relied on piece shape. Those in the control group…

  20. Two-Dimensional Parson's Puzzles: The Concept, Tools, and First Observations

    ERIC Educational Resources Information Center

    Ihantola, Petri; Karavirta, Ville

    2011-01-01

    Parson's programming puzzles are a family of code construction assignments where lines of code are given, and the task is to form the solution by sorting and possibly selecting the correct code lines. We introduce a novel family of Parson's puzzles where the lines of code need to be sorted in two dimensions. The vertical dimension is used to order…

  1. An Alternative Evaluation: Online Puzzle as a Course-End Activity

    ERIC Educational Resources Information Center

    Genç, Zülfü; Aydemir, Emrah

    2015-01-01

    Purpose: The purpose of this study is to determine whether the use of online puzzles in the instructional process has an effect on student achievement and learning retention. This study examined students ' perception and experiences on use of puzzle as an alternative evaluation tool. To achieve this aim, the following hypotheses were tested: using…

  2. Puzzle-Based Learning in Engineering Mathematics: Students' Attitudes

    ERIC Educational Resources Information Center

    Klymchuk, Sergiy

    2017-01-01

    The article reports on the results of two case studies on the impact of the regular use of puzzles as a pedagogical strategy in the teaching and learning of engineering mathematics. The intention of using puzzles is to engage students' emotions, creativity and curiosity and also to enhance their generic thinking skills and lateral thinking…

  3. The King and Prisoner Puzzle: A Way of Introducing the Components of Logical Structures

    ERIC Educational Resources Information Center

    Roh, Kyeong Hah; Lee, Yong Hah; Tanner, Austin

    2016-01-01

    The purpose of this paper is to provide issues related to student understanding of logical components that arise when solving word problems. We designed a logic problem called the King and Prisoner Puzzle--a linguistically simple, yet logically challenging problem. In this paper, we describe various student solutions to the puzzle and discuss the…

  4. Crossword Puzzle Makes It Fun: Introduce Green Manufacturing in Wood Technology Courses

    ERIC Educational Resources Information Center

    Iley, John L.; Hague, Doug

    2012-01-01

    Sustainable, or "green," manufacturing and its practices are becoming more and more a part of today's industry, including wood product manufacturing. This article provides introductory information on green manufacturing in wood technology and a crossword puzzle based on green manufacturing terms. The authors use the puzzle at the college level to…

  5. Two-Dimensional Parson's Puzzles: The Concept, Tools, and First Observations

    ERIC Educational Resources Information Center

    Ihantola, Petri; Karavirta, Ville

    2011-01-01

    Parson's programming puzzles are a family of code construction assignments where lines of code are given, and the task is to form the solution by sorting and possibly selecting the correct code lines. We introduce a novel family of Parson's puzzles where the lines of code need to be sorted in two dimensions. The vertical dimension is used to order…

  6. Using the Tower of Hanoi Puzzle to Infuse Your Mathematics Classroom with Computer Science Concepts

    ERIC Educational Resources Information Center

    Marzocchi, Alison S.

    2016-01-01

    This article suggests that logic puzzles, such as the well-known Tower of Hanoi puzzle, can be used to introduce computer science concepts to mathematics students of all ages. Mathematics teachers introduce their students to computer science concepts that are enacted spontaneously and subconsciously throughout the solution to the Tower of Hanoi…

  7. Establishing Information Security Systems via Optical Imaging

    DTIC Science & Technology

    2015-08-11

    to encrypt and authenticate information for data/images storage and transmission, including optical systems for secured information. 15. SUBJECT...TERMS Optical Imaging, Optical Cryptosystems , Diffractive Imaging, Optical Encryption 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT SAR 18...sector). The main objective is to develop optical imaging technologies to encrypt and authenticate information for data/images storage and

  8. Alliteration in medicine: a puzzling profusion of p's

    PubMed Central

    Hayden, Gregory F

    1999-01-01

    Problem Puzzling, progressive profusion of alliterative “p's” in published papers. Purpose To depict this particular “p” predominance with pinpoint precision. Plan Periodic, painstaking perusal of periodicals by a professor of paediatrics. Proposal The “p” plethora is positively perplexing and potentially perturbing. Alliteration is a literary device consisting of repetition of the same starting sound in several words in a sentence.1 Consider, for example, Shakespeare's playful parody of alliteration in Peter Quince's prologue in A Midsummer Night's Dream: “Whereat with blade, with bloody blameful blade, He bravely broach'd his boiling bloody breast.” Alliteration has appeared frequently in the medical literature—for example: “Respiratory syncytial virus—from chimps with colds to conundrums and cures;”2 “The choreas: of faints, fevers, and families;”3 “Coronary artery stents—gauging, gorging, and gouging;”4 “Moschcowitz, multimers, and metalloprotease;”5 “Alagille syndrome: a nutritional niche for Notch;”6 “Theodor Billroth: success with sutures and strings.”7 Perusing the medical literature with alliteration in mind, I have become perplexed by a peculiar propensity for the letter “p” to be placed in prominent positions. Consider for a moment the alliterative content of the BMJ, a prestigious periodical also published in Pakistani, Polish, and Portuguese. Perhaps the prime example is a piece entitled “A potpourri of parasites in poetry and proverb,”8 but the journal has presented articles addressing such topics as paracetamol poisoning,9 practitioners' pressure to prescribe,10 physicians' partnerships with patients,11 partnerships for prevention in public playgrounds,12 and pregnancy outcomes which have been persistently poor.13 Other topics have included patients' priorities,14 the political process of puzzling out private versus public priorities,15 and the ponderous problem of whether the priorities in

  9. An Empirical Evaluation of Puzzle-Based Learning as an Interest Approach for Teaching Introductory Computer Science

    ERIC Educational Resources Information Center

    Merrick, K. E.

    2010-01-01

    This correspondence describes an adaptation of puzzle-based learning to teaching an introductory computer programming course. Students from two offerings of the course--with and without the puzzle-based learning--were surveyed over a two-year period. Empirical results show that the synthesis of puzzle-based learning concepts with existing course…

  10. Optical energy storage and reemission based weak localization of light and accompanying random lasing action in disordered Nd{sup 3+} doped (Pb, La)(Zr, Ti)O{sub 3} ceramics

    SciTech Connect

    Xu, Long; Zhao, Hua; Xu, Caixia; Zhang, Siqi; Zhang, Jingwen

    2014-08-14

    Multi-mode random lasing action and weak localization of light were evidenced and studied in normally transparent but disordered Nd{sup 3+} doped (Pb,La)(Zr,Ti)O{sub 3} ceramics. Noticeable localized zone and multi-photon process were observed under strong pumping power. A tentative phenomenological physical picture was proposed by taking account of diffusive process, photo-induced scattering, and optical energy storage process as dominant factors in elucidating the weak localization of light observed. Both the decreased transmittance (increased reflectivity) of light and the observed long lasting fading-off phenomenon supported the physical picture proposed by us.

  11. The puzzling reliability of the Force Concept Inventory

    NASA Astrophysics Data System (ADS)

    Lasry, Nathaniel; Rosenfield, Steven; Dedic, Helena; Dahan, Ariel; Reshef, Orad

    2011-09-01

    The Force Concept Inventory (FCI) has influenced the development of many research-based pedagogies. However, no data exists on the FCI's internal consistency or test-retest reliability. The FCI was administered twice to one hundred students during the first week of classes in an electricity and magnetism course with no review of mechanics between test administrations. High Kuder-Richardson reliability coefficient values, which estimate the average correlation of scores obtained on all possible halves of the test, suggest strong internal consistency. However, 31% of the responses changed from test to retest, suggesting weak reliability for individual questions. A chi-square analysis shows that change in responses was neither consistent nor completely random. The puzzling conclusion is that although individual FCI responses are not reliable, the FCI total score is highly reliable.

  12. On a puzzle about bremsstrahlung as described by coaccelerated observers

    SciTech Connect

    Pena, I.; Chryssomalakos, C.; Sudarsky, D.; Corichi, A.

    2005-10-15

    We consider anew some puzzling aspects of the equivalence of the quantum field theoretical description of bremsstrahlung from the inertial and accelerated observer's perspectives. More concretely, we focus on the seemingly paradoxical situation that arises when noting that the radiating source is in thermal equilibrium with the thermal state of the quantum field in the wedge in which it is located, and thus its presence does not change there the state of the field, while it clearly does not affect the state of the field on the opposite wedge. How then is the state of the quantum field on the future wedge changed, as it must in order to account for the changed energy-momentum tensor there? This and related issues are carefully discussed.

  13. Resolution to the B{yields}{pi}K puzzle

    SciTech Connect

    Li Hsiangnan; Mishima, Satoshi; Sanda, A.I.

    2005-12-01

    We calculate the important next-to-leading-order contributions to the B{yields}{pi}K, {pi}{pi} decays from the vertex corrections, the quark loops, and the magnetic penguins in the perturbative QCD approach. It is found that the latter two reduce the leading-order penguin amplitudes by about 10% and modify only the B{yields}{pi}K branching ratios. The main effect of the vertex corrections is to increase the small color-suppressed tree amplitude by a factor of 3, which then resolves the large difference between the direct CP asymmetries of the B{sup 0}{yields}{pi}{sup {+-}}K{sup {+-}} and B{sup {+-}}{yields}{pi}{sup 0}K{sup {+-}} modes. The puzzle from the large B{sup 0}{yields}{pi}{sup 0}{pi}{sup 0} branching ratio still remains.

  14. Ambiguity aversion and household portfolio choice puzzles: Empirical evidence*

    PubMed Central

    Dimmock, Stephen G.; Kouwenberg, Roy; Mitchell, Olivia S.; Peijnenburg, Kim

    2017-01-01

    We test the relation between ambiguity aversion and five household portfolio choice puzzles: nonparticipation in equities, low allocations to equity, home-bias, own-company stock ownership, and portfolio under-diversification. In a representative US household survey, we measure ambiguity preferences using custom-designed questions based on Ellsberg urns. As theory predicts, ambiguity aversion is negatively associated with stock market participation, the fraction of financial assets in stocks, and foreign stock ownership, but it is positively related to own-company stock ownership. Conditional on stock ownership, ambiguity aversion is related to portfolio under-diversification, and during the financial crisis, ambiguity-averse respondents were more likely to sell stocks. PMID:28458446

  15. Ambiguity aversion and household portfolio choice puzzles: Empirical evidence.

    PubMed

    Dimmock, Stephen G; Kouwenberg, Roy; Mitchell, Olivia S; Peijnenburg, Kim

    2016-03-01

    We test the relation between ambiguity aversion and five household portfolio choice puzzles: nonparticipation in equities, low allocations to equity, home-bias, own-company stock ownership, and portfolio under-diversification. In a representative US household survey, we measure ambiguity preferences using custom-designed questions based on Ellsberg urns. As theory predicts, ambiguity aversion is negatively associated with stock market participation, the fraction of financial assets in stocks, and foreign stock ownership, but it is positively related to own-company stock ownership. Conditional on stock ownership, ambiguity aversion is related to portfolio under-diversification, and during the financial crisis, ambiguity-averse respondents were more likely to sell stocks.

  16. The missing pieces of the HCV entry puzzle.

    PubMed

    Ogden, Sarah C; Tang, Hengli

    The past decade has witnessed steady and rapid progress in HCV research, which has led to the recent breakthrough in therapies against this significant human pathogen. Yet a deeper understanding of the life cycle of the virus is required to develop more affordable treatments and to advance vaccine design. HCV entry presents both a challenge for scientific research and an opportunity for alternative intervention approaches, owning to its highly complex nature and the myriad of players involved. More than half a dozen cellular proteins are implicated in HCV entry; and a more definitive picture regarding the structures of the glycoproteins is emerging. A role of apolipoproteins in HCV entry has also been established. Still, major questions remain, and the answers to these, which we summarize in this review, will hopefully close the gaps in our understanding and complete the puzzle that is HCV entry.

  17. The missing pieces of the HCV entry puzzle

    PubMed Central

    Ogden, Sarah C; Tang, Hengli

    2015-01-01

    The past decade has witnessed steady and rapid progress in HCV research, which has led to the recent breakthrough in therapies against this significant human pathogen. Yet a deeper understanding of the life cycle of the virus is required to develop more affordable treatments and to advance vaccine design. HCV entry presents both a challenge for scientific research and an opportunity for alternative intervention approaches, owning to its highly complex nature and the myriad of players involved. More than half a dozen cellular proteins are implicated in HCV entry; and a more definitive picture regarding the structures of the glycoproteins is emerging. A role of apolipoproteins in HCV entry has also been established. Still, major questions remain, and the answers to these, which we summarize in this review, will hopefully close the gaps in our understanding and complete the puzzle that is HCV entry. PMID:25960762

  18. Peelle's pertinent puzzle using the Monte Carlo technique

    SciTech Connect

    Kawano, Toshihiko; Talou, Patrick; Burr, Thomas; Pan, Feng

    2009-01-01

    We try to understand the long-standing problem of the Peelle's Pertinent Puzzle (PPP) using the Monte Carlo technique. We allow the probability density functions to be any kind of form to assume the impact of distribution, and obtain the least-squares solution directly from numerical simulations. We found that the standard least squares method gives the correct answer if a weighting function is properly provided. Results from numerical simulations show that the correct answer of PPP is 1.1 {+-} 0.25 if the common error is multiplicative. The thought-provoking answer of 0.88 is also correct, if the common error is additive, and if the error is proportional to the measured values. The least squares method correctly gives us the most probable case, where the additive component has a negative value. Finally, the standard method fails for PPP due to a distorted (non Gaussian) joint distribution.

  19. Gaia's view of the λ Boo star puzzle

    NASA Astrophysics Data System (ADS)

    Murphy, Simon J.; Paunzen, Ernst

    2017-04-01

    The evolutionary status of the chemically peculiar class of λ Boo stars has been intensely debated. It is now agreed that the λ Boo phenomenon affects A stars of all ages, from star formation to the terminal age main sequence, but the cause of the chemical peculiarity is still a puzzle. We revisit the debate of their ages and temperatures in order to shed light on the phenomenon, using the new parallaxes in Gaia Data Release 1 with existing Hipparcos parallaxes and multicolour photometry. We find that no single formation mechanism is able to explain all the observations, and suggest that there are multiple channels producing λ Boo spectra. The relative importance of these channels varies with age, temperature and environment.

  20. Lambda-nuclear interactions and hyperon puzzle in neutron stars

    NASA Astrophysics Data System (ADS)

    Haidenbauer, J.; Meißner, U.-G.; Kaiser, N.; Weise, W.

    2017-06-01

    Brueckner theory is used to investigate the in-medium properties of a Λ-hyperon in nuclear and neutron matter, based on hyperon-nucleon interactions derived within SU(3) chiral effective field theory (EFT). It is shown that the resulting Λ single-particle potential U_{Λ}(p_{Λ} = 0,ρ) becomes strongly repulsive for densities ρ of two-to-three times that of normal nuclear matter. Adding a density-dependent effective Λ N-interaction constructed from chiral Λ NN three-body forces increases the repulsion further. Consequences of these findings for neutron stars are discussed. It is argued that for hyperon-nuclear interactions with properties such as those deduced from the SU(3) EFT potentials, the onset for hyperon formation in the core of neutron stars could be shifted to much higher density which, in turn, could pave the way for resolving the so-called hyperon puzzle.

  1. A Jigsaw Puzzle Layer Cake of Spatial Data

    NASA Astrophysics Data System (ADS)

    Ma, Xiaogang; Fox, Peter

    2014-05-01

    The Infrastructure for Spatial Information in Europe (INSPIRE; http://inspire.jrc.ec.europa.eu) is a European Union (EU) directive that aims to provide a legal framework to share environmental spatial data among public sector organizations across Europe and to facilitate public access to data. To meet these goals, INSPIRE's organization is analogous to a layer cake in which each layer is composed of interlocking pieces of a jigsaw puzzle. The metaphor, although mixed, is apt (see additional supporting information in the online version of this article), and as researchers outside the program, we offer our perspective on how INSPIRE may address challenges raised by the variety of data themes and the wide coverage of collaborators.

  2. Nucleophilic Addition vs. Substituion: A Puzzle for the Organic Laboratory

    NASA Astrophysics Data System (ADS)

    Silversmith, Ernest F.

    1998-02-01

    An experiment has been devised that allows a student to prove that nucleophilic addition to a keto group predominates over nucleophilic substitution at an ester group in a case in which both are theoretically possible. The student reacts ethyl 2-acetyl-3-oxobutanoate with hydrazine and with phenylhydrazine and shows, by 1H NMR spectroscopy, that the products are 4-carbethoxypyrazoles and not 4-acetylpyrazolones. Students may also use 1H NMR to show that ethyl 2-acetyl-3-oxobutanoate is 100% enolized in carbon tetrachloride solution. The experiment asks the student to solve a puzzle, which adds to the student's interest and sense of excitement. It can also be used to teach students how to conduct a literature search. The products obtained are described in the literature, so students can be asked to compare their melting points with those of other workers.

  3. The Puzzles of the Vela Pulsar-Wind Nebula

    NASA Astrophysics Data System (ADS)

    Kargaltsev, Oleg; Pavlov, G. G.

    2008-03-01

    Very few pulsar wind nebulae (PWNe) can be studied at the level of detail comparable to that achieved for the Crab PWN. The nearby Vela PWN is the best candidate for such an in-depth study. Using Chandra ACIS observations of 2000-2002, we produced a "movie" which shows that not only the NW outer jet, reported by Pavlov et al. (2003), but also the entire bright Vela PWN is remarkably variable. The most dramatic changes occur in the outer arc, the SE inner jet, and the bright knots in the SE part of the inner PWN. On a time scale of 1-3 weeks, the outer arc changes its brightness, shape, and spectrum, the knots move, disappear and appear again, while the SE inner jet changes its brightness and size. In contrast with the Crab PWN, we see no moving "wisps". The observed changes can be attributed to instabilities in the pulsar wind and to varying density/pressure in the ambient medium. Deep combined images show that the inner arc is part of a ring, but the pulsar is offset from its plane. The large width of the SE outer "jet" suggests either an intrinsic asymmetry of the SE and NW polar outflows or that the SE jet broadens in a low-pressure cavity behind the moving pulsar. We also found a puzzling "bar" at the base of the inner SE jet, possibly a shock in a polar outflow. An adaptively binned spectral map demonstrates that the inner PWN elements have extremely hard spectra (significantly harder than those of the Crab inner PWN), incompatible with those predicted by the shock acceleration models. Overall, the Vela PWN shows a wealth of puzzling features, different from the Crab; their nature can be understood in a specially designed series of Chandra ACIS observations.

  4. Holographic content addressable storage

    NASA Astrophysics Data System (ADS)

    Chao, Tien-Hsin; Lu, Thomas; Reyes, George

    2015-03-01

    We have developed a Holographic Content Addressable Storage (HCAS) architecture. The HCAS systems consists of a DMD (Digital Micromirror Array) as the input Spatial Light Modulator (SLM), a CMOS (Complementary Metal-oxide Semiconductor) sensor as the output photodetector and a photorefractive crystal as the recording media. The HCAS system is capable of performing optical correlation of an input image/feature against massive reference data set stored in the holographic memory. Detailed system analysis will be reported in this paper.

  5. Genome puzzle master (GPM): an integrated pipeline for building and editing pseudomolecules from fragmented sequences

    PubMed Central

    Zhang, Jianwei; Kudrna, Dave; Mu, Ting; Li, Weiming; Copetti, Dario; Yu, Yeisoo; Goicoechea, Jose Luis; Lei, Yang; Wing, Rod A.

    2016-01-01

    Motivation: Next generation sequencing technologies have revolutionized our ability to rapidly and affordably generate vast quantities of sequence data. Once generated, raw sequences are assembled into contigs or scaffolds. However, these assemblies are mostly fragmented and inaccurate at the whole genome scale, largely due to the inability to integrate additional informative datasets (e.g. physical, optical and genetic maps). To address this problem, we developed a semi-automated software tool—Genome Puzzle Master (GPM)—that enables the integration of additional genomic signposts to edit and build ‘new-gen-assemblies’ that result in high-quality ‘annotation-ready’ pseudomolecules. Results: With GPM, loaded datasets can be connected to each other via their logical relationships which accomplishes tasks to ‘group,’ ‘merge,’ ‘order and orient’ sequences in a draft assembly. Manual editing can also be performed with a user-friendly graphical interface. Final pseudomolecules reflect a user’s total data package and are available for long-term project management. GPM is a web-based pipeline and an important part of a Laboratory Information Management System (LIMS) which can be easily deployed on local servers for any genome research laboratory. Availability and Implementation: The GPM (with LIMS) package is available at https://github.com/Jianwei-Zhang/LIMS Contacts: jzhang@mail.hzau.edu.cn or rwing@mail.arizona.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:27318200

  6. Optical disks

    NASA Technical Reports Server (NTRS)

    Lopez-Swafford, B.

    1986-01-01

    A comprehensive overview of the different types of optical storage technology is presented. Research efforts to integrate this technology into the VAX/VMS environment are discussed. In addition, plans for future applications of optical disk technology are described. The applications should prove to be beneficial to the NSSDC user community as a whole. Of particular interest is the concentration on the collaboration with the Dynamics Explorer project.

  7. Nondestructive and continuous monitoring of oxygen levels in modified atmosphere packaged ready-to-eat mixed salad products using optical oxygen sensors, and its effects on sensory and microbiological counts during storage.

    PubMed

    Hempel, A; O'Sullivan, M G; Papkovsky, D B; Kerry, J P

    2013-07-01

    The objective of this study was to determine the percentage oxygen consumption of fresh, respiring ready-to-eat (RTE) mixed leaf salad products (Iceberg salad leaf, Caesar salad leaf, and Italian salad leaf). These were held under different modified atmosphere packaging (MAP) conditions (5% O2 , 5% CO2 , 90% N2 (MAPC-commercial control), 21% O2 , 5% CO2 , 74% N2 (MAP 1), 45% O2 , 5% CO2 , 50% N2 (MAP 2), and 60% O2 , 5% CO2 , 35% N2 (MAP 3)) and 4 °C for up to 10 d. The quality and shelf-life stability of all packaged salad products were evaluated using sensory, physiochemical, and microbial assessment. Oxygen levels in all MAP packs were measured on each day of analysis using optical oxygen sensors allowing for nondestructive assessment of packs. Analysis showed that with the exception of control packs, oxygen levels for all MAP treatments decreased by approximately 10% after 7 d of storage. Oxygen levels in control packs were depleted after 7 d of storage. This appears to have had no detrimental effect on either the sensory quality or shelf-life stability of any of the salad products investigated. Additionally, the presence of higher levels of oxygen in modified atmosphere packs did not significantly improve product quality or shelf-life stability; however, these additional levels of oxygen were freely available to fresh respiring produce if required. This study shows that the application of optical sensors in MAP packs was successful in nondestructively monitoring oxygen level, or changes in oxygen level, during refrigerated storage of RTE salad products. © 2013 Institute of Food Technologists®

  8. First Detection of a Strong Magnetic Field on a Bursty Brown Dwarf: Puzzle Solved

    NASA Astrophysics Data System (ADS)

    Berdyugina, S. V.; Harrington, D. M.; Kuzmychov, O.; Kuhn, J. R.; Hallinan, G.; Kowalski, A. F.; Hawley, S. L.

    2017-09-01

    We report the first direct detection of a strong, 5 kG magnetic field on the surface of an active brown dwarf. LSR J1835+3259 is an M8.5 dwarf exhibiting transient radio and optical emission bursts modulated by fast rotation. We have detected the surface magnetic field as circularly polarized signatures in the 819 nm sodium lines when an active emission region faced the Earth. Modeling Stokes profiles of these lines reveals the effective temperature of 2800 K and log gravity acceleration of 4.5. These parameters place LSR J1835+3259 on evolutionary tracks as a young brown dwarf with the mass of 55+/- 4{M}{{J}} and age of 22 ± 4 Myr. Its magnetic field is at least 5.1 kG and covers at least 11% of the visible hemisphere. The active region topology recovered using line profile inversions comprises hot plasma loops with a vertical stratification of optical and radio emission sources. These loops rotate with the dwarf in and out of view causing periodic emission bursts. The magnetic field is detected at the base of the loops. This is the first time that we can quantitatively associate brown dwarf non-thermal bursts with a strong, 5 kG surface magnetic field and solve the puzzle of their driving mechanism. This is also the coolest known dwarf with such a strong surface magnetic field. The young age of LSR J1835+3259 implies that it may still maintain a disk, which may facilitate bursts via magnetospheric accretion, like in higher-mass T Tau-type stars. Our results pave a path toward magnetic studies of brown dwarfs and hot Jupiters.

  9. Holographic data storage crystals for LDEF (A0044)

    NASA Technical Reports Server (NTRS)

    Callen, W. R.; Gaylord, T. K.

    1984-01-01

    Electro-optic holographic recording systems were developed. The spaceworthiness of electro-optic crystals for use in ultrahigh capacity space data storage and retrieval systems are examined. The crystals for this experiment are included with the various electro-optical components of LDEF experiment. The effects of long-duration exposure on active optical system components is investigated. The concept of data storage in an optical-phase holographic memory is illustrated.

  10. Mass storage technology in networks

    NASA Astrophysics Data System (ADS)

    Ishii, Katsunori; Takeda, Toru; Itao, Kiyoshi; Kaneko, Reizo

    1990-08-01

    Trends and features of mass storage subsystems in network are surveyed and their key technologies spotlighted. Storage subsystems are becoming increasingly important in new network systems in which communications and data processing are systematically combined. These systems require a new class of high-performance mass-information storage in order to effectively utilize their processing power. The requirements of high transfer rates, high transactional rates and large storage capacities, coupled with high functionality, fault tolerance and flexibility in configuration, are major challenges in storage subsystems. Recent progress in optical disk technology has resulted in improved performance of on-line external memories to optical disk drives, which are competing with mid-range magnetic disks. Optical disks are more effective than magnetic disks in using low-traffic random-access file storing multimedia data that requires large capacity, such as in archive use and in information distribution use by ROM disks. Finally, it demonstrates image coded document file servers for local area network use that employ 130mm rewritable magneto-optical disk subsystems.

  11. Energy Storage

    DTIC Science & Technology

    2007-05-01

    Release, Distribution Unlimited) Activities • Modeling & Simulation: – Solar availability – Effective airship solar surface area – System energy ...2007, The MITRE Corporation(Approved for Public Release, Distribution Unlimited) Energy Storage Perry Hamlyn 781-271-2137 • phamlyn@mitre.org DARPA...REPORT DATE MAY 2007 2. REPORT TYPE 3. DATES COVERED 00-00-2007 to 00-00-2007 4. TITLE AND SUBTITLE Energy Storage 5a. CONTRACT NUMBER 5b. GRANT

  12. Liver regeneration: a picture emerges from the puzzle.

    PubMed

    LaBrecque, D

    1994-08-01

    Liver regeneration remains a fascinating enigma. Many pieces of the puzzle have been elucidated, but as each piece is discovered, it is found to be composed of many smaller pieces, some of which are missing, and the multiple interlocking edges with other pieces of the puzzle remain poorly understood. The true initiating event or events remain unclear. The essential requirement for activation of immediate early genes is generally unchallenged. C-jun is essential for normal hepatogenesis in mouse development and it appears to be required for proliferation in response to injury, as well. Yet, nefenopin and cyproterone acetate induce hyperplastic responses in the liver with no induction of c-fos, c-myc, or c-jun. HGF is the single most potent liver mitogen yet discovered. However, levels of HGF do not correlate with the degree of liver regeneration, and high concentrations exist in conditions such as those in chronic hemodialysis patients who have no evidence of regeneration and minimal evidence of liver injury. Numerous conditions exist that induce immediate early genes and yet do not lead to cell proliferation. Thus, the availability of mitogens by themselves is not sufficient to induce regeneration, and the induction of immediate early genes is not sufficient to lead to regeneration. Whereas the isolated parenchymal cell culture system has been extremely valuable in identifying an increasing number of stimulatory and inhibitory substances and identifying the initial steps in their mechanisms of action, this simple system does not take into account the extremely complex interactions of these multiple growth factors in vivo and the interaction of the parenchymal cell with the other cellular and structural components of the liver. All must be accounted for in a complete model of liver regeneration. Parenchymal cell growth itself appears to be controlled by a series of steps, each of which requires the presence of specific growth regulators, which may be stimulators or

  13. Fibromyalgia: A Puzzling and Painful Condition | NIH MedlinePlus the Magazine

    MedlinePlus

    ... of this page please turn JavaScript on. Feature: Fibromyalgia Fibromyalgia: A Puzzling and Painful Condition Past Issues / Spring ... or internal organs. Wise Choices: Feeling Better with Fibromyalgia Get enough sleep. Getting the right kind of ...

  14. Mitigating Distributed Denial of Service Attacks in an Anonymous Routing Environment: Client Puzzles and Tor

    DTIC Science & Technology

    2006-03-01

    by a distributed system like Tor. The protocol must account for Tor’s threat environment and also address any secondary DDoS or anonymity attacks...Mitigating Distributed Denial of Service Attacks in an Anonymous Routing Environment: Client Puzzles and Tor THESIS Nicholas A. Fraser, Captain, USAF... Anonymous Routing Environment: Client Puzzles and Tor THESIS Presented to the Faculty Department of Electrical and Computer Engineering Graduate

  15. A Play on Words: Using Cognitive Computing as a Basis for AI Solvers in Word Puzzles

    NASA Astrophysics Data System (ADS)

    Manzini, Thomas; Ellis, Simon; Hendler, James

    2015-12-01

    In this paper we offer a model, drawing inspiration from human cognition and based upon the pipeline developed for IBM's Watson, which solves clues in a type of word puzzle called syllacrostics. We briefly discuss its situation with respect to the greater field of artificial general intelligence (AGI) and how this process and model might be applied to other types of word puzzles. We present an overview of a system that has been developed to solve syllacrostics.

  16. A Play on Words: Using Cognitive Computing as a Basis for AI Solvers in Word Puzzles

    NASA Astrophysics Data System (ADS)

    Manzini, Thomas; Ellis, Simon; Hendler, James

    2015-12-01

    In this paper we offer a model, drawing inspiration from human cognition and based upon the pipeline developed for IBM's Watson, which solves clues in a type of word puzzle called syllacrostics. We briefly discuss its situation with respect to the greater field of artificial general intelligence (AGI) and how this process and model might be applied to other types of word puzzles. We present an overview of a system that has been developed to solve syllacrostics.

  17. Storage Technology: A Review of Options and Their Implications for Electronic Publishing.

    ERIC Educational Resources Information Center

    Arnold, Stephen E.

    1991-01-01

    Describes computer storage devices and suggests implications for electronic publishing. Highlights include magnetic storage media, including digital audio tape (DAT); high-capacity magnetic drives; optical storage technologies, including CD-ROM and WORM; magneto-optical drives; and a sidebar that discusses other storage technologies. (21…

  18. Economics, human biology and inequality: A review of "puzzles" and recent contributions from a Deatonian perspective.

    PubMed

    Baten, Joerg

    2016-11-18

    The Nobel laureate Angus Deaton concentrated his work on puzzling developments and phenomena in economics. Puzzles are exciting elements in economics, because readers feel challenged by the question of how they can be solved. Among the puzzles analyzed by Deaton are: (1) Mortality increase of white, U.S. non-Hispanic men (2000 to today); (2) Why are height and income sometimes closely correlated, but not always?; (3) Height inequality among males and females; and (4) The Indian puzzle of declining consumption of calories during overall expenditure growth. This article reviews these "puzzles" and the main insights that Deaton derived from their discussion insofar as they pertain to the biological aspects of human development. I will focus on the field of this journal, Economics and Human Biology, in which Deaton has been very active over the last two decades. I will also document some of the responses by other scholars and their contributions to these puzzles, as they relate to the field of economics and human biology.

  19. Basics of Videodisc and Optical Disk Technology.

    ERIC Educational Resources Information Center

    Paris, Judith

    1983-01-01

    Outlines basic videodisc and optical disk technology describing both optical and capacitance videodisc technology. Optical disk technology is defined as a mass digital image and data storage device and briefly compared with other information storage media including magnetic tape and microforms. The future of videodisc and optical disk is…

  20. Cohabitants' perspective on housing adaptations: a piece of the puzzle.

    PubMed

    Granbom, Marianne; Taei, Afsaneh; Ekstam, Lisa

    2017-01-31

    As part of the Swedish state-funded healthcare system, housing adaptations are used to promote safe and independent living for disabled people in ordinary housing through the elimination of physical environmental barriers in the home. The aim of this study was to describe the cohabitants' expectations and experiences of how a housing adaptation, intended for the partner, would impact their everyday life. In-depth interviews were conducted with cohabitants of nine people applying for a housing adaptation, initially at the time of the application and then again 3 months after the housing adaptation was installed. A longitudinal analysis was performed including analysis procedures from Grounded Theory. The findings revealed the expectations and experiences in four categories: partners' activities and independence; cohabitants' everyday activities and caregiving; couples' shared recreational/leisure activities; and housing decisions. A core category putting the intervention into perspective was called 'Housing adaptations - A piece of the puzzle'. From the cohabitants' perspective, new insights on housing adaptations emerged, which are important to consider when planning and carrying out successful housing adaptations. © 2017 Nordic College of Caring Science.

  1. Is the proton radius puzzle evidence of extra dimensions?

    NASA Astrophysics Data System (ADS)

    Dahia, F.; Lemos, A. S.

    2016-08-01

    The proton charge radius inferred from muonic hydrogen spectroscopy is not compatible with the previous value given by CODATA-2010, which, on its turn, essentially relies on measurements of the electron-proton interaction. The proton's new size was extracted from the 2S-2P Lamb shift in the muonic hydrogen, which showed an energy excess of 0.3 meV in comparison to the theoretical prediction, evaluated with the CODATA radius. Higher-dimensional gravity is a candidate to explain this discrepancy, since the muon-proton gravitational interaction is stronger than the electron-proton interaction and, in the context of braneworld models, the gravitational potential can be hugely amplified in short distances when compared to the Newtonian potential. Motivated by these ideas, we study a muonic hydrogen confined in a thick brane. We show that the muon-proton gravitational interaction modified by extra dimensions can provide the additional separation of 0.3 meV between the 2S and 2P states. In this scenario, the gravitational energy depends on the higher-dimensional Planck mass and indirectly on the brane thickness. Studying the behavior of the gravitational energy with respect to the brane thickness in a realistic range, we find constraints for the fundamental Planck mass that solve the proton radius puzzle and are consistent with previous experimental bounds.

  2. The Puzzle of Visual Development: Behavior and Neural Limits

    PubMed Central

    2016-01-01

    The development of visual function takes place over many months or years in primate infants. Visual sensitivity is very poor near birth and improves over different times courses for different visual functions. The neural mechanisms that underlie these processes are not well understood despite many decades of research. The puzzle arises because research into the factors that limit visual function in infants has found surprisingly mature neural organization and adult-like receptive field properties in very young infants. The high degree of visual plasticity that has been documented during the sensitive period in young children and animals leaves the brain vulnerable to abnormal visual experience. Abnormal visual experience during the sensitive period can lead to amblyopia, a developmental disorder of vision affecting ∼3% of children. This review provides a historical perspective on research into visual development and the disorder amblyopia. The mismatch between the status of the primary visual cortex and visual behavior, both during visual development and in amblyopia, is discussed, and several potential resolutions are considered. It seems likely that extrastriate visual areas further along the visual pathways may set important limits on visual function and show greater vulnerability to abnormal visual experience. Analyses based on multiunit, population activity may provide useful representations of the information being fed forward from primary visual cortex to extrastriate processing areas and to the motor output. PMID:27911740

  3. Graphene spintronics: puzzling controversies and challenges for spin manipulation

    NASA Astrophysics Data System (ADS)

    Roche, Stephan; Valenzuela, Sergio O.

    2014-03-01

    This article presents the current puzzling controversy between theory and experimental results concerning the mechanisms leading to spin relaxation in graphene-based materials. On the experimental side, it is surprising that regardless of the quality of the graphene monolayer, which is characterized by the carrier mobility, the typical Hanle precession measurements yield spin diffusion times (τs) in the order of τs ˜ 0.1-1 ns (at low temperatures), which is several orders of magnitude below the theoretical estimates based on the expected low intrinsic spin-orbit coupling in graphene. The results are weakly dependent on whether graphene is deposited onto SiO2 or boron-nitride substrates or is suspended, with the mobility spanning 3 orders of magnitude. On the other hand, extraction form two-terminal magnetoresistance measurements, accounting for contact effects results in τs ˜ 0.1 µs, and corresponding diffusion lengths of about 100 µm up to room temperature. Such discrepancy jeopardizes further progress towards spin manipulation on a lateral graphene two-dimensional platform. After a presentation of basic concepts, we here discuss state-of-the-art literature and the limits of all known approaches to describe spin transport in massless-Dirac fermions, in which the effects of strong local spin-orbit coupling ceases to be accessible with perturbative approaches. We focus on the limits of conventional views of spin transport in graphene and offer novel perspectives for further progress.

  4. The Puzzling Case of Hyperexcitability in Amyotrophic Lateral Sclerosis

    PubMed Central

    Bae, Jong Seok; Simon, Neil G.; Menon, Parvathi; Vucic, Steve

    2013-01-01

    The development of hyperexcitability in amyotrophic lateral sclerosis (ALS) is a well-known phenomenon. Despite controversy as to the underlying mechanisms, cortical hyperexcitability appears to be closely related to the interplay between excitatory corticomotoneurons and inhibitory interneurons. Hyperexcitability is not a static phenomenon but rather shows a pattern of progression in a spatiotemporal aspect. Cortical hyperexcitability may serve as a trigger to the development of anterior horn cell degeneration through a 'dying forward' process. Hyperexcitability appears to develop during the early disease stages and gradually disappears in the advanced stages of the disease, linked to the destruction of corticomotorneuronal pathways. As such, a more precise interpretation of these unique processes may provide new insight regarding the pathophysiology of ALS and its clinical features. Recently developed technologies such as threshold tracking transcranial magnetic stimulation and automated nerve excitability tests have provided some clues about underlying pathophysiological processes linked to hyperexcitability. Additionally, these novel techniques have enabled clinicians to use the specific finding of hyperexcitability as a useful diagnostic biomarker, enabling clarification of various ALS-mimic syndromes, and the prediction of disease development in pre-symptomatic carriers of familial ALS. In terms of nerve excitability tests for peripheral nerves, an increase in persistent Na+ conductances has been identified as a major determinant of peripheral hyperexcitability in ALS, inversely correlated with the survival in ALS. As such, the present Review will focus primarily on the puzzling theory of hyperexcitability in ALS and summarize clinical and pathophysiological implications for current and future ALS research. PMID:23626643

  5. Brodmann area 12: an historical puzzle relevant to FTLD.

    PubMed

    Kawamura, M; Miller, M W; Ichikawa, H; Ishihara, K; Sugimoto, A

    2011-05-03

    Brodmann brain maps, assembled in 1909, are still in use, but understanding of their animal-human homology is uncertain. Furthermore, in 1909, Brodmann did not identify human area 12 (BA12), a location now important to understanding of frontotemporal lobar degeneration (FTLD). We re-examined Brodmann's areas, both animal and human, in his 1909 monograph and other literature, both historical and contemporary, and projected BA12 onto the medial surface of a fixed human brain to show its location. We found Brodmann did identify human BA12 in later maps (1910 and 1914), but that his brain areas, contrary to his own aims as a comparative anatomist, are now used as physiologic loci in human brain. Because of its current link with frontotemporal dementia, BA12's transition from animal (1909) to human (1910 and 1914) is not only an historical puzzle. It impacts how Brodmann's areas, based on comparative animal-human cytoarchitecture, are widely used in current research as functional loci in human brain.

  6. The 30Mg(t ,p )32Mg "puzzle" reexamined

    NASA Astrophysics Data System (ADS)

    Macchiavelli, A. O.; Crawford, H. L.; Campbell, C. M.; Clark, R. M.; Cromaz, M.; Fallon, P.; Jones, M. D.; Lee, I. Y.; Salathe, M.; Brown, B. A.; Poves, A.

    2016-11-01

    Background: Competing interpretations of the results of a 30Mg(t ,p )32Mg measurement populating the ground state and 02+ state in 32Mg, both limited to a two-state mixing description, have left an open question regarding the nature of the 32Mg ground state. Purpose: Inspired by recent shell-model calculations, we explore the possibility of a consistent interpretation of the available data for the low-lying 0+ states in 32Mg by expanding the description from two-level to three-level mixing. Methods: A phenomenological three-level mixing model of unperturbed 0p0h, 2p2h, and 4p4h states is applied to describe both the excitation energies in 32Mg and the transfer reaction cross sections. Results: Within this approach, self-consistent solutions exist that provide good agreement with the available experimental information obtained from the 30Mg(t ,p )32Mg reaction. Conclusion: The inclusion of the third state, namely the 4p4h configuration, resolves the "puzzle" that results from a two-levelmodel interpretation of the same data. In our analysis, the 32Mg ground state emerges naturally as dominated by intruder (2p2h and 4p4h) configurations, at the 95% level.

  7. Fanconi Anemia Proteins and Their Interacting Partners: A Molecular Puzzle

    PubMed Central

    Kaddar, Tagrid; Carreau, Madeleine

    2012-01-01

    In recent years, Fanconi anemia (FA) has been the subject of intense investigations, primarily in the DNA repair research field. Many discoveries have led to the notion of a canonical pathway, termed the FA pathway, where all FA proteins function sequentially in different protein complexes to repair DNA cross-link damages. Although a detailed architecture of this DNA cross-link repair pathway is emerging, the question of how a defective DNA cross-link repair process translates into the disease phenotype is unresolved. Other areas of research including oxidative metabolism, cell cycle progression, apoptosis, and transcriptional regulation have been studied in the context of FA, and some of these areas were investigated before the fervent enthusiasm in the DNA repair field. These other molecular mechanisms may also play an important role in the pathogenesis of this disease. In addition, several FA-interacting proteins have been identified with roles in these “other” nonrepair molecular functions. Thus, the goal of this paper is to revisit old ideas and to discuss protein-protein interactions related to other FA-related molecular functions to try to give the reader a wider perspective of the FA molecular puzzle. PMID:22737580

  8. Hyperon puzzle: hints from quantum Monte Carlo calculations.

    PubMed

    Lonardoni, Diego; Lovato, Alessandro; Gandolfi, Stefano; Pederiva, Francesco

    2015-03-06

    The onset of hyperons in the core of neutron stars and the consequent softening of the equation of state have been questioned for a long time. Controversial theoretical predictions and recent astrophysical observations of neutron stars are the grounds for the so-called hyperon puzzle. We calculate the equation of state and the neutron star mass-radius relation of an infinite systems of neutrons and Λ particles by using the auxiliary field diffusion Monte Carlo algorithm. We find that the three-body hyperon-nucleon interaction plays a fundamental role in the softening of the equation of state and for the consequent reduction of the predicted maximum mass. We have considered two different models of three-body force that successfully describe the binding energy of medium mass hypernuclei. Our results indicate that they give dramatically different results on the maximum mass of neutron stars, not necessarily incompatible with the recent observation of very massive neutron stars. We conclude that stronger constraints on the hyperon-neutron force are necessary in order to properly assess the role of hyperons in neutron stars.

  9. The puzzling origin of the Martian Northern Lowlands.

    NASA Astrophysics Data System (ADS)

    Altieri, F.; Carrozzo, G.; Carli, C.; Geminale, A.; Bellucci, G.

    Surface studies of the northern lowlands of Mars have shown that this region has undergone a complex history including volcanism, sedimentary deposition and secondary modification by climate change. Despite these analyses, the origin and the evolution of this region are still debated. No clear and definitive evidences have been found so far to conclude whether these plains were formed by a giant impact, were once covered by an ocean or were filled by a large quantity of lavas. In the visible and infrared spectral range, the northern lowlands differ from southern terrains in the NIR negative slope while they exhibit VNIR spectra similar to the southern pyroxene-rich areas (Carrozzo et al., 2012). These observations, combined with both recent detection of mafic minerals at higher spatial resolution by CRISM (Salvatore et al., 2010) and recent results of Horgan and Bell (2012), supports that their mineralogy is linked to weathered basalts with a glassy component. In addition to this, the spectral similarity of Acidalia area with the northern circumpolar sand dunes, apart from the hydration features, suggests that the weathering processes that took place there could be related to past glacial activity, in agreement with superficial morphology showing glacial structures. Aim of this work is to combine the OMEGA mineralogical maps with morphological features (Tanaka et al., 2011) and investigate possible terrestrial analogues in order to give some constrains on the composition and origin of these puzzling Martian terrains.

  10. Wolves in the Great Lakes region: a phylogeographic puzzle.

    PubMed

    Randi, Ettore

    2010-10-01

    Empirical studies demonstrate that natural hybridization in animals is more common than thought so far (Mallet 2005), particularly among species that originated recently through cycles of population contraction-expansion arising from climate changes over the last glacial period, the Pleistocene. In addition, the post-glacial global growth of human populations has fostered anthropogenic hybridization events, mediated by habitat changes, the persecution of large predators and the introduction of alien species (Allendorf et al. 2001). The Canis lineage shows cases of both natural and anthropogenic hybridization, exacerbating the controversy about the number of species that should be formally validated in the taxonomic lists, the evolutionary role of genetic introgression and the ways to manage hybrids with invading wild or domesticated populations. The study by Wheeldon et al. (2010), published in this issue of Molecular Ecology, adds a new piece to the intricate puzzle of evolution and taxonomy of Canis in North America. They show that sympatric wolves (C. lupus) and coyotes (C. latrans) are not (extensively) hybridizing in the western North American Great Lakes region (GLR). Widespread hybridization between coyotes and a genetically distinct, but closely related, wolf-like population (the eastern wolf) occurred in the northeastern regions of North America. In Wheeldon et al.'s (2010) opinion, these data should prove definitely that two different species of wolf (the western gray wolf C. lupus and the eastern wolf C. lycaon) and their hybrids are distributed across the GLR.

  11. Energy Storage

    SciTech Connect

    Mukundan, Rangachary

    2014-09-30

    Energy storage technology is critical if the U.S. is to achieve more than 25% penetration of renewable electrical energy, given the intermittency of wind and solar. Energy density is a critical parameter in the economic viability of any energy storage system with liquid fuels being 10 to 100 times better than batteries. However, the economical conversion of electricity to fuel still presents significant technical challenges. This project addressed these challenges by focusing on a specific approach: efficient processes to convert electricity, water and nitrogen to ammonia. Ammonia has many attributes that make it the ideal energy storage compound. The feed stocks are plentiful, ammonia is easily liquefied and routinely stored in large volumes in cheap containers, and it has exceptional energy density for grid scale electrical energy storage. Ammonia can be oxidized efficiently in fuel cells or advanced Carnot cycle engines yielding water and nitrogen as end products. Because of the high energy density and low reactivity of ammonia, the capital cost for grid storage will be lower than any other storage application. This project developed the theoretical foundations of N2 catalysis on specific catalysts and provided for the first time experimental evidence for activation of Mo 2N based catalysts. Theory also revealed that the N atom adsorbed in the bridging position between two metal atoms is the critical step for catalysis. Simple electrochemical ammonia production reactors were designed and built in this project using two novel electrolyte systems. The first one demonstrated the use of ionic liquid electrolytes at room temperature and the second the use of pyrophosphate based electrolytes at intermediate temperatures (200 – 300 ºC). The mechanism of high proton conduction in the pyrophosphate materials was found to be associated with a polyphosphate second phase contrary to literature claims and ammonia production rates as high as 5X 10

  12. Cathodochromic storage device

    NASA Technical Reports Server (NTRS)

    Bosomworth, D. R.; Moles, W. H.

    1969-01-01

    A memory and display device has been developed by combing a fast phosphor layer with a cathodochromic layer in a cathode ray tube. Images are stored as patterns of electron beam induced optical density in the cathodo-chromic material. The stored information is recovered by exciting the backing, fast phosphor layer with a constant current electron beam and detecting the emitted radiation which is modulated by absorption in the cathodochromic layer. The storage can be accomplished in one or more TV frames (1/30 sec each). More than 500 TV line resolution and close to 2:1 contrast ratio are possible. The information storage time in a dark environment is approximately 24 hours. A reconstituted (readout) electronic video signal can be generated continuously for times in excess of 10 minutes or periodically for several hours.

  13. First-principles calculations of structural, elastic, electronic, and optical properties of perovskite-type KMgH3 crystals: novel hydrogen storage material.

    PubMed

    Reshak, Ali H; Shalaginov, Mikhail Y; Saeed, Yasir; Kityk, I V; Auluck, S

    2011-03-31

    We report a first-principles study of structural and phase stability in three different structures of perovskite-types KMgH(3) according to H position. While electronic and optical properties were measured only for stable perovskite-type KMgH(3), our calculated structural parameters are found in good agreement with experiment and other theoretical results. We also study the electronic charge density space distribution contours in the (200), (101), and (100) crystallographic planes, which gives better insight picture of chemical bonding between K-H, K-Mg-H, and Mg-H. Moreover, we have calculated the electronic band structure dispersion, total, and partial density of electron states to study the band gap origin and the contribution of s-band of H, s and p-band of Mg in the valence band, and d-band of K in the conduction band. Furthermore, optical features such as dielectric functions, refractive indices, extinction coefficient, optical reflectivity, absorption coefficients, optical conductivities, and loss functions of stable KMgH(3) were calculated for photon energies up to 40 eV.

  14. ON THE PUZZLE OF SPACE WEATHERING ALTERATION OF BASALTIC ASTEROIDS

    SciTech Connect

    Marchi, S.; Lazzarin, M.; Magrin, S.; De Sanctis, M. C. E-mail: monica.lazzarin@unipd.i E-mail: mariacristina.desanctis@iasf-roma.inaf.i

    2010-10-01

    The majority of basaltic asteroids are found in the inner main belt, although a few have also been observed in the outer main belt and near-Earth space. These asteroids-referred to as V-types-have surface compositions that resemble that of the 530 km sized asteroid Vesta. Besides the compositional similarity, dynamical evidence also links many V-type asteroids to Vesta. Moreover, Vesta is one of the few asteroids to have been identified as source of specific classes of meteorites, the howardite, eucrite, and diogenite achondrites (HEDs). Despite the general consensus on the outlined scenario, several questions remain unresolved. In particular, it is not clear if the observed spectral diversity among Vesta, V-types, and HEDs is due to space weathering, as is thought to be the case for S-type asteroids. In this Letter, SDSS photometry is used to address the question of whether the spectral diversity among candidate V-types and HEDs can be explained by space weathering. We show that visible spectral slopes of V-types are systematically redder with respect to HEDs, in a similar way to what is found for ordinary chondrite meteorites and S-types. On the assumption that space weathering is responsible for the slope mismatch, we estimated an upper limit for the reddening timescale of about 0.5 Ga. Nevertheless, the observed slope mismatch between HEDs and V-types poses several puzzles to understanding its origin. The implication of our findings is also discussed in light of the Dawn mission to Vesta.

  15. Hyperon puzzle, hadron-quark crossover and massive neutron stars

    NASA Astrophysics Data System (ADS)

    Masuda, Kota; Hatsuda, Tetsuo; Takatsuka, Tatsuyuki

    2016-03-01

    Bulk properties of cold and hot neutron stars are studied on the basis of the hadron-quark crossover picture where a smooth transition from the hadronic phase to the quark phase takes place at finite baryon density. By using a phenomenological equation of state (EOS) "CRover", which interpolates the two phases at around 3 times the nuclear matter density (ρ0, it is found that the cold NSs with the gravitational mass larger than 2M_{odot} can be sustained. This is in sharp contrast to the case of the first-order hadron-quark transition. The radii of the cold NSs with the CRover EOS are in the narrow range (12.5 ± 0.5) km which is insensitive to the NS masses. Due to the stiffening of the EOS induced by the hadron-quark crossover, the central density of the NSs is at most 4 ρ0 and the hyperon-mixing barely occurs inside the NS core. This constitutes a solution of the long-standing hyperon puzzle. The effect of color superconductivity (CSC) on the NS structures is also examined with the hadron-quark crossover. For the typical strength of the diquark attraction, a slight softening of the EOS due to two-flavor CSC (2SC) takes place and the maximum mass is reduced by about 0.2M_{odot}. The CRover EOS is generalized to the supernova matter at finite temperature to describe the hot NSs at birth. The hadron-quark crossover is found to decrease the central temperature of the hot NSs under isentropic condition. The gravitational energy release and the spin-up rate during the contraction from the hot NS to the cold NS are also estimated.

  16. Cardio-vascular activity of catestatin: interlocking the puzzle pieces.

    PubMed

    Mazza, R; Tota, B; Gattuso, A

    2015-01-01

    Catestatin (CST), the Chromogranin A (CgA)-derived cationic and hydrophobic peptide, firstly recognized as an endogenous inhibitor of catecholamine secretion, functions as a physiological brake of the adreno-sympathetic-chromaffin system. Its wide spectrum of activities includes relevant multilevel cardiovascular and antihypertensive influences. At central systemic level, CST seems to modulate the autonomic cardiovascular control possibly acting on baroreceptor afferent fibers of the nucleus tractus solitarius. This, as well as clinical and experimental (CgA-KO mice) evidences point to an important role of CST in the determinism and prevention of essential hypertension. At organ level, CST exerts myocardial (negative inotropy and lusitropy) effects and potently vasodilates endothelin-1 (ET-1)-preconstricted coronaries through β2-adrenergic receptor (AR)-Gi/o protein-nitric oxide (NO)-cGMP signalling, while counterbalancing β adrenergic (ISO) stimulation. The contractile myocardial effects have been deeply analysed in fish and amphibian hearts, highlighting finely diversified mechanisms of action. CST also acts as cardioprotective agent in both pre- and post-conditioning through NO-dependent mechanisms implicating the Reperfusion Injury Salvage Kinase (RISK) signalling and the activation of mitoKATP channels. The CST-elicited cardiotropic and coronarotropic influences, along with the recently discovered proangiogenic and regulatory effects in glucose and lipid metabolism, contribute to delineate an integrated and updated picture of the peptide which emerges as a pleiotropic hormone with a wide range of cytokine-like characteristics. The aim of this review is to interlock some older and more recent evidences which may help to better perceive the subtle links and differences among the puzzle pieces that still need to be deciphered.

  17. The puzzle of immune phenotypes of childhood asthma.

    PubMed

    Landgraf-Rauf, Katja; Anselm, Bettina; Schaub, Bianca

    2016-12-01

    new immunological molecules, the complex puzzle of childhood asthma is still far from being completed. Addressing the current challenges of distinct clinical asthma and wheeze phenotypes, including their stability and underlying endotypes, involves addressing the interplay of innate and adaptive immune regulatory mechanisms in large, interdisciplinary cohorts.

  18. Emergence of Life on Earth: A Physicochemical Jigsaw Puzzle.

    PubMed

    Spitzer, Jan

    2017-01-01

    We review physicochemical factors and processes that describe how cellular life can emerge from prebiotic chemical matter; they are: (1) prebiotic Earth is a multicomponent and multiphase reservoir of chemical compounds, to which (2) Earth-Moon rotations deliver two kinds of regular cycling energies: diurnal electromagnetic radiation and seawater tides. (3) Emerging colloidal phases cyclically nucleate and agglomerate in seawater and consolidate as geochemical sediments in tidal zones, creating a matrix of microspaces. (4) Some microspaces persist and retain memory from past cycles, and others re-dissolve and re-disperse back into the Earth's chemical reservoir. (5) Proto-metabolites and proto-biopolymers coevolve with and within persisting microspaces, where (6) Macromolecular crowding and other non-covalent molecular forces govern the evolution of hydrophilic, hydrophobic, and charged molecular surfaces. (7) The matrices of microspaces evolve into proto-biofilms of progenotes with rudimentary but evolving replication, transcription, and translation, enclosed in unstable cell envelopes. (8) Stabilization of cell envelopes 'crystallizes' bacteria-like genetics and metabolism with low horizontal gene transfer-life 'as we know it.' These factors and processes constitute the 'working pieces' of the jigsaw puzzle of life's emergence. They extend the concept of progenotes as the first proto-cellular life, connected backward in time to the cycling chemistries of the Earth-Moon planetary system, and forward to the ancient cell cycle of first bacteria-like organisms. Supra-macromolecular models of 'compartments first' are preferred: they facilitate macromolecular crowding-a key abiotic/biotic transition toward living states. Evolutionary models of metabolism or genetics 'first' could not have evolved in unconfined and uncrowded environments because of the diffusional drift to disorder mandated by the second law of thermodynamics.

  19. Desiccation tolerance of Sphagnum revisited: a puzzle resolved.

    PubMed

    Hájek, T; Vicherová, E

    2014-07-01

    As ecosystem engineers, Sphagnum mosses control their surroundings through water retention, acidification and peat accumulation. Because water retention avoids desiccation, sphagna are generally intolerant to drought; however, the literature on Sphagnum desiccation tolerance (DT) provides puzzling results, indicating the inducible nature of their DT. To test this, various Sphagnum species and other mesic bryophytes were hardened to drought by (i) slow drying; (ii) ABA application and (iii) chilling or frost. DT tolerance was assessed as recovery of chlorophyll fluorescence parameters after severe desiccation. We monitored the seasonal course of DT in bog bryophytes. Under laboratory conditions, following initial de-hardening, untreated Sphagnum shoots lacked DT; however, DT was induced by all hardening treatments except chilling, notably by slow drying, and in Sphagnum species of the section Cuspidata. In the field, sphagna in hollows and lawns developed DT several times during the growing season, responding to reduced precipitation and a lowered water table. Hummock and aquatic species developed DT only in late autumn, probably as a response to frost. Sphagnum protonemata failed to develop DT; hence, desiccation may limit Sphagnum establishment in drier habitats with suitable substrate chemistry. Desiccation avoiders among sphagna form compact hummocks or live submerged; thus, they do not develop DT in the field, lacking the initial desiccation experience, which is frequent in hollow and lawn habitats. We confirmed the morpho-physiological trade-off: in contrast to typical hollow sphagna, hummock species invest more resources in water retention (desiccation avoidance), while they have a lower ability to develop physiological DT. © 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.

  20. Hydrogen Storage

    SciTech Connect

    2008-11-01

    This 2-page fact sheet provides a brief introduction to hydrogen storage technologies. Intended for a non-technical audience, it explains the different ways in which hydrogen can be stored, as well as the technical challenges and research goals for storing hydrogen on board a vehicle.