WorldWideScience

Sample records for cancellation

  1. Scientific journal cancellations

    CERN Multimedia

    The Library

    2001-01-01

    Earlier this year the Scientific Information Policy Board (SIPB) requested the Library and the Working Group for Acquisitions to revise the current printed journal collection in order to cancel those titles that are less required. Savings could then be used for the development of other collections and particularly electronic resources needed to support CERN current research activities. A list of proposed cancellations was drawn and posted on the Library web pages: http://library.cern.ch/library_general/cancel.html The SIPB invites every one to check if any of the titles are of importance to their work, in which case you are invited to inform the Library before the 25th of September by sending an e-mail to: eliane.chaney@cern.ch Titles not reconsidered by the users will be cancelled by the end of the year. Thank you, The Library

  2. Adaptive cancellation techniques

    Science.gov (United States)

    1983-11-01

    An adaptive signal canceller has been evaluated for the enhancement of pulse signal reception during the transmission of a high power ECM jamming signal. The canceller design is based on the use of DRFM(Digital RF Memory) technology as part of an adaptive multiple tapped delay line. The study includes analysis of relationship of tap spacing and waveform bandwidth, survey of related documents in areas of sidelobe cancellers, transversal equalizers, and adaptive filters, and derivation of control equations and corresponding control processes. The simulation of overall processes included geometric analysis of the multibeam transmitting antenna, multiple reflection sources and the receiving antenna; waveforms, tap spacings and bandwidths; and alternate control algorithms. Conclusions are provided regarding practical system control algorithms, design characteristics and limitations.

  3. Offset cancelling circuit

    NARCIS (Netherlands)

    Wiegerink, Remco J.; Seevinck, Evert; de Jager, Wim

    1989-01-01

    A monolithic offset cancelling circuit to reduce the offset voltage at an integrated audio-amplifier output is described. This offset voltage is detected using a low-pass filter with a very large time constant for which only one small on-chip capacitor is needed. The circuit was realized with a

  4. Geneva University - Cancelled

    CERN Multimedia

    Université de Genève

    2010-01-01

    École de physique - Département de physique nucléaire et corspusculaire 24, quai Ernest-Ansermet 1211 GENEVA 4 Tel: (022) 379 62 73 - Fax: (022) 379 69 92 Monday 19 April 2010 17h00 - Stückelberg Auditorium Into the darkness: Simulating the distribution of dark matter in our Universe Prof. Volker Springel - Heidelberg Institute for Theoretical Studies   THE COLLOQUIUM IS CANCELLED. Prof. Markus Büttiker

  5. Offset cancelling circuit

    OpenAIRE

    Wiegerink, Remco J.; Seevinck, Evert; de Jager, Wim

    1989-01-01

    A monolithic offset cancelling circuit to reduce the offset voltage at an integrated audio-amplifier output is described. This offset voltage is detected using a low-pass filter with a very large time constant for which only one small on-chip capacitor is needed. The circuit was realized with a bipolar cell-based semicustom array. Measurements have shown that a -3-dB bandwidth below 5 Hz can be realized with a capacitor value of 50 pF. The resulting offset voltage at the audio-amplifier outpu...

  6. HUD Initiated Activity Cancellation Reports

    Data.gov (United States)

    Department of Housing and Urban Development — This monthly report displays all HOME activities automatically cancelled by IDIS. Effective January 1, 2011, and the beginning of every month thereafter, committed...

  7. 77 FR 19747 - Proposed Cancelation

    Science.gov (United States)

    2012-04-02

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF TRANSPORTATION Office of the Secretary Proposed Cancelation of the Air Taxi Authority Of VIH Cougar Helicopters, Inc... cause why it should not issue an order finding that VIH Cougar Helicopters, Inc. is not a U.S. citizen...

  8. CERN Library - Scientific journal cancellations

    CERN Multimedia

    2004-01-01

    Due to the constant increase of the subscription costs of scientific journals and the current budget restrictions, the Scientific Information Policy Board has mandated the Working Group for Acquisitions (WGA) together with the Library to propose a list of titles to be cancelled at the end of 2004. As a first step, the WGA has identified the scientific journals listed at the web site below as candidates for cancellation. The choice has been guided by the personal experience of the WGA members, consultation of other expert CERN staff for highly specialized titles, and by criteria such as subscription price, impact factor, and - where available - access statistics for electronic journals. The list also accounts for the fact that many titles are subscribed to in 'packages' such that a cancellation of individual titles would not lead to any cost savings. We invite users to carefully check the list on the Library homepage (http://library.cern.ch/). If you find any title that you consider critically important for y...

  9. Surgery cancellations at a public hospital

    Directory of Open Access Journals (Sweden)

    Erika Pittelkow

    2008-12-01

    Full Text Available Objective: To determine the frequency of cancellation of scheduledsurgeries at a public hospital in the city of São Paulo, and to identifythe reasons of cancellation. Methods: A descriptive, exploratory,retrospective study, with quantitative analysis, of records ofprocedures cancelled and medical charts of patients whose surgerieswere cancelled, between January 2006 and July 2007. Results: Ofthe 6,149 (100% surgeries scheduled for the period surveyed, 701(11.4% were canceled and 5,448 (88.6% conducted; among thesurgeries cancelled, most were general surgeries (237/33.8% andorthopedic surgery (200/28.5%; surgeons or assistant surgeons(518/73.9% and anesthesiologists (183/26.1% were responsible forcancellations. The primary reasons for cancellation were unfavorableclinical status of patients (225/32.1%, no show up of patients(119/17.0%, change in medical management (79/11.3%, patientnot appropriately prepared (53/7.5% and lack of material (52/7.4%.Conclusions: This study enabled identifying the frequency and causesof surgical cancellations at a public hospital, so as to contribute toimproving professional performance in this area.

  10. 44 CFR 206.376 - Loan cancellation.

    Science.gov (United States)

    2010-10-01

    ... money borrowed to pay amounts FEMA does not advance toward completion of approved Project Applications... cancellation. (a) FEMA shall cancel repayment of all or part of a Special Community Disaster Loan to the extent...-month period beginning September 1, 2005, FEMA will prorate the revenues and expenses for the partial...

  11. Noise canceling in-situ detection

    Science.gov (United States)

    Walsh, David O.

    2014-08-26

    Technologies applicable to noise canceling in-situ NMR detection and imaging are disclosed. An example noise canceling in-situ NMR detection apparatus may comprise one or more of a static magnetic field generator, an alternating magnetic field generator, an in-situ NMR detection device, an auxiliary noise detection device, and a computer.

  12. DIF Cancellation in the Rasch Model.

    Science.gov (United States)

    Wyse, Adam E

    2013-01-01

    Differential item functioning (DIF) cancellation occurs when the cumulative effect of an item or set of items exhibiting DIF against one subgroup cancels with other items that exhibit DIF against the comparison group and hence results in non-existent DIF at the test level. This paper investigates DIF cancellation in the context of Rasch measurement. It is shown that this phenomenon is not a property of the Rasch model, but rather, a function of the manner in which item parameters are estimated and the way that DIF impacts these estimates. The conditions under which DIF cancellation would exist when using the Rasch model are suggested and a proof is provided to support this suggestion. Empirical examples are provided to refute prior suggestions that DIF cancellation always exists if the Rasch model is used.

  13. CDMA with interference cancellation for multiprobe missions

    Science.gov (United States)

    Divsalar, D.; Simon, M. K.

    1995-01-01

    Code division multiple-access spread spectrum has been proposed for use in future multiprobe/multispacecraft missions. This article considers a general parallel interference-cancellation scheme that significantly reduces the degradation effect of probe (user) interference but with a lesser implementation complexity than the maximum-likelihood technique. The scheme operates on the fact that parallel processing simultaneously removes from each probe (user) the total interference produced by the remaining most reliably received probes (users) accessing the channel. The parallel processing can be done in multiple stages. The proposed scheme uses tentative decision devices with different optimum thresholds at the multiple stages to produce the most reliably received data for generation and cancellation of probe/spacecraft interference. The one-stage interference cancellation was analyzed for two types of tentative decision devices, namely, hard and null zone decisions. Simulation results are given for one- and two-stage interference cancellation for equal as well as unequal received power probes.

  14. Active noise cancellation in hearing devices

    DEFF Research Database (Denmark)

    2013-01-01

    Disclosed is a hearing device system comprising at least one hearing aid circuitry and at least one active noise cancellation unit, the at least one hearing aid circuitry comprises at least one input transducer adapted to convert a first audio signal to an electric audio signal; a signal processor...... connected to the at least one input transducer and adapted to process said electric audio signal by at least partially correcting for a hearing loss of a user; an output transducer adapted to generate from at least said processed electric audio signal a sound pressure in an ear canal of the user, whereby...... the generated sound pressure is at least partially corrected for the hearing loss of the user; ; the at least one active noise cancellation unit being adapted to provide an active noise cancellation signal adapted to perform active noise cancellation of an acoustical signal entering the ear canal in addition...

  15. LMS filter for noise cancellation using Simulink

    Science.gov (United States)

    Talele, K. T.; Shrivastav, Ashish; Utekar, Kunal; Deshpande, Abhishek

    2011-06-01

    In this paper we have proposed the simplified implementation of adaptive noise cancellation using LMS filter. The LMS algorithm belongs to the family of stochastic gradient algorithms. It is one of the efficient algorithms in adaptive filtering.

  16. Estimation of In vivo Cancellous Bone Elasticity

    Science.gov (United States)

    Otani, Takahiko; Mano, Isao; Tsujimoto, Toshiyuki; Yamamoto, Tadahito; Teshima, Ryota; Naka, Hiroshi

    2009-07-01

    The effect of decreasing bone density (a symptom of osteoporosis) is greater for cancellous bone than for dense cortical bone, because cancellous bone is metabolically more active. Therefore, the bone density or bone mineral density of cancellous bone is generally used to estimate the onset of osteoporosis. Elasticity or elastic constant is a fundamental mechanical parameter and is directly related to the mechanical strength of bone. Accordingly, elasticity is a preferable parameter for assessing fracture risk. A novel ultrasonic bone densitometer LD-100 has been developed to determine the mass density and elasticity of cancellous bone with a spatial resolution comparable to that of peripheral quantitative computed tomography. Bone density and bone elasticity are evaluated using ultrasonic parameters based on fast and slow waves in cancellous bone by modeling the ultrasonic wave propagation path. Elasticity is deduced from the measured bone density and the propagation speed of the fast wave. Thus, the elasticity of cancellous bone is approximately expressed by a cubic equation of bone density.

  17. The design of 'cancelable' data acquisition environments

    Science.gov (United States)

    Shortridge, Keith; Farrell, Tony J.

    2004-09-01

    This paper presents a discussion of the architectural issues resulting when software systems need to cancel operations once they have been initiated. This may seem a minor issue, but our experience is that this requirement can have a huge effect on the design of instrumental software environments. A number of major constraints on the structure of command-based environments such as the AAO's DRAMA system can be traced to the perceived need to be able to cancel any operation cleanly. This becomes particularly difficult to implement if these operations involve significant amounts of time or even potentially indefinite amounts of time, such as operations involving blocking I/O. In general, the cleanest results come from having a process or thread cancel itself, rather than relying on the ability to cancel it externally, but this turns the problem into one of finding mechanisms whereby processes can discover, reliably, that they need to cancel themselves. As system architectures are considered for the next generation of telescopes, it seems timely to consider these design problems and even to what extent the ideal requirement of cleanly cancellable operations may have been reduced by the move towards queue-scheduled operations and away from traditional interactive observing.

  18. Robustness Analysis of the Adaptive Periodic Noise Canceller Applied to Resonance Cancellation

    OpenAIRE

    Timoney, Joseph; Foley, Brian

    2000-01-01

    In this paper the criteria determining robustness of a LMS-driven Adaptive Periodic Noise Canceller (APNC) when applied to the cancellation of coloured interference signals are investigated. The upper bound on the algorithm stepsize is the crucial quantity for determining robustness and here relevant expressions for this upper bound are developed, followed by experimental evaluation.

  19. Tonometric arterial pulse sensor with noise cancellation.

    Science.gov (United States)

    Ciaccio, Edward J; Drzewiecki, Gary M

    2008-10-01

    Arterial tonometry provides for the continuous and noninvasive recording of the arterial pressure waveform. However, tonometers are affected by motion artifact that degrades the signal. An arterial tonometer was constructed using two piezoelectric transducers centered within a solid base. In two subjects, one transducer was positioned over the radial pulse (p) and the other was positioned on the wrist not overlying the pulse (n). The presence of induced motion artifact and any noise was removed after signal digitization by noise cancellation. Besides fixed weighting, two adaptive algorithms were used for cancellation-LMS and differential steepest descent (DSD). Criteria were developed for comparison of the adaptive techniques. The best fixed weighting for noise cancellation was w=0.6. For fixed-weighting, LMS, and DSD, the mean peak-to-peak errors were 1.22+/-0.54, 1.18+/-0.30, and 1.16+/-0.23 V, respectively, and the mean point-to-point errors were 15.86+/-3.15, 11.40+/-1.96, and 10.13+/-1.25 V, respectively. Noise cancellation using a common-mode reference input substantially reduces motion artifact and other noise from the acquired tonometric arterial pulse signal. Adaptive weighting provides better cancellation than fixed weighting, likely because the mechanical gain at the transducer-skin interface is time-varying.

  20. Optimal Reinsertion of Cancelled Train Lines

    DEFF Research Database (Denmark)

    Groth, Julie Jespersen; Clausen, Jens

    2006-01-01

    One recovery strategy in case of a major disruption in rail network is to cancel all trains on a specific line of the network. When the disturbance has ended, the cancelled line must be reinserted as soon as possible. In this article we present a mixed integer programming (MIP) model for calculat....... The model finds the optimal solution in an average of 0.5 CPU seconds in each test case.......One recovery strategy in case of a major disruption in rail network is to cancel all trains on a specific line of the network. When the disturbance has ended, the cancelled line must be reinserted as soon as possible. In this article we present a mixed integer programming (MIP) model...... for calculating the best way to reinsert cancelled train lines in a rail network covered by a periodic timetable. Using a high abstraction level it has been possible to incorporate the temporal aspect in the model only relying on the information embedded in the train identification numbers of each departure...

  1. Efficient modulation cancellation using reflective SOAs.

    Science.gov (United States)

    Dúill, S Ó; Marazzi, L; Parolari, P; Brenot, R; Koos, C; Freude, W; Leuthold, J

    2012-12-10

    Modulation cancellation and signal inversion are demonstrated within reflective semiconductor optical amplifiers. The effect is necessary to implement colorless optical network units for network end-users, where downstream signals need to be erased in order to reuse the carrier for upstream transmission. The results presented here indicate that reflective semiconductor optical amplifiers possess the perfect high-speed all-optical gain saturation characteristics to completely cancel the downstream modulation at microwatt optical power levels and are thus the prime candidate to be constituents of future optical network units. Theoretical considerations are supported by experiments that show the cancellation of signals with a 6 dB extinction ratio at 2.5 Gbit/s.

  2. Improved CDMA Performance Using Parallel Interference Cancellation

    Science.gov (United States)

    Simon, Marvin; Divsalar, Dariush

    1995-01-01

    This report considers a general parallel interference cancellation scheme that significantly reduces the degradation effect of user interference but with a lesser implementation complexity than the maximum-likelihood technique. The scheme operates on the fact that parallel processing simultaneously removes from each user the interference produced by the remaining users accessing the channel in an amount proportional to their reliability. The parallel processing can be done in multiple stages. The proposed scheme uses tentative decision devices with different optimum thresholds at the multiple stages to produce the most reliably received data for generation and cancellation of user interference. The 1-stage interference cancellation is analyzed for three types of tentative decision devices, namely, hard, null zone, and soft decision, and two types of user power distribution, namely, equal and unequal powers. Simulation results are given for a multitude of different situations, in particular, those cases for which the analysis is too complex.

  3. Cancellous bone as an antibiotic carrier.

    Science.gov (United States)

    Witsø, E; Persen, L; Løseth, K; Benum, P; Bergh, K

    2000-02-01

    We compared the release characteristics of antibiotics from in vivo and in vitro processed morselized cancellous bone. The bone was impregnated with 7 antibiotics and compressed into a wire-mesh cylinder. In vitro, the bone was processed by daily transfer of the cylinder with its contents into test tubes with broth. The amount of antibiotic eluted from the bone was measured after 1, 3 and 7 days. In vivo, the cylinder was implanted intramuscularly in the interscapular region in rats. After 1, 3 and 7 days, the cylinder was removed and the amount of antibiotic eluted in broth was measured. The results showed that morselized cancellous bone can act as a carrier of antibiotics in vitro and in vivo. The elution profiles of netilmicin-, vancomycin-, clindamycin- and rifampicin-impregnated cancellous bone processed in vitro and in vivo were similar.

  4. Cloaking through cancellation of diffusive wave scattering

    Science.gov (United States)

    Chen, P. Y.; Guenneau, S.; Bağcı, H.; Salama, K. N.; Alù, A.

    2016-01-01

    A new cloaking mechanism, which makes enclosed objects invisible to diffusive photon density waves, is proposed. First, diffusive scattering from a basic core–shell geometry, which represents the cloaked structure, is studied. The conditions of scattering cancellation in a quasi-static scattering regime are derived. These allow for tailoring the diffusivity constant of the shell enclosing the object so that the fields scattered from the shell and the object cancel each other. This means that the photon flow outside the cloak behaves as if the cloaked object were not present. Diffusive light invisibility may have potential applications in hiding hot spots in infrared thermography or tissue imaging. PMID:27616925

  5. Active noise cancellation in a suspended interferometer

    CERN Document Server

    Driggers, Jennifer C; Pepper, Keenan; Adhikari, Rana

    2011-01-01

    We demonstrate feed-forward vibration isolation on a suspended Fabry-Perot interferometer using Wiener filtering and a variant of the common Least Mean Square (LMS) adaptive filter algorithm. We compare the experimental results with theoretical estimates of the cancellation efficiency. Using data from the recent LIGO Science Run, we also estimate the impact of this technique on full scale gravitational wave interferometers. In the future, we expect to use this technique to also remove acoustic, magnetic, and gravitational noise perturbations from the LIGO interferometers. This noise cancellation technique is simple enough to implement in standard laboratory environments and can be used to improve SNR for a variety of high precision experiments.

  6. Nonlinear Adaptive Filter for MEMS Gyro Error Cancellation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Nonlinear adaptive filters (NAF) can learn deterministic gyro errors and cancel the error’s effect from attitude estimates. By completely canceling...

  7. Patient experiences with interventions to reduce surgery cancellations

    DEFF Research Database (Denmark)

    Hovlid, Einar; von Plessen, Christian; Haug, Kjell

    2013-01-01

    The cancellation of planned surgery harms patients, increases waiting times and wastes scarce health resources. Previous studies have evaluated interventions to reduce cancellations from medical and management perspectives; these have focused on cost, length of stay, improved efficiency, and redu...

  8. Why is surgery cancelled? A retrospective evaluation | Chamisa ...

    African Journals Online (AJOL)

    ... and 1.8% of the cancellations respectively. Conclusion. Last-minute cancellation of surgery was a significant problem, and appreciation of the usual reasons for cancellations can improve theatre utilisation and avoid inconveniencing patients and their families. South African Journal of Surgery Vol. 46 (3) 2008: pp. 79-81 ...

  9. Case review analysis of operating room decisions to cancel surgery.

    Science.gov (United States)

    Chang, Ju-Hsin; Chen, Ke-Wei; Chen, Kuen-Bao; Poon, Kin-Shing; Liu, Shih-Kai

    2014-07-23

    Cancellation of surgery close to scheduled time causes a waste of healthcare resources. The current study analyzes surgery cancellations occurring after the patient has been prepared for the operating room, in order to see whether improvements in the surgery planning process may reduce the number of cancellations. In a retrospective chart review of operating room surgery cancellations during the period from 2006 to 2011, cancellations were divided into the following categories: inadequate NPO; medical; surgical; system; airway; incomplete evaluation. The relative use of these reasons in relation to patient age and surgical department was then evaluated. Forty-one percent of cancellations were for other than medical reasons. Among these, 17.7% were due to incomplete evaluation, and 8.2% were due to family issues. Sixty seven percent of cancelled cases eventually received surgery. The relative use of individual reasons for cancellation varied with patient age and surgical department. The difference between cancellations before and after anesthesia was dependent on the causes of cancellation, but not age, sex, ASA status, or follow-up procedures required. Almost half of the cancellations were not due to medical reasons, and these cancellations could be reduced by better administrative and surgical planning and better communication with the patient and/or his family.

  10. 77 FR 5012 - Rescission of Certain Product Cancellations

    Science.gov (United States)

    2012-02-01

    ... rescind the cancellation of Baker Petrolite Corporation's (BPC) product, EPA Reg. No. 010707-00055; Bio... this rescission do? This Notice rescinds the cancellation of BPC's product, EPA registration number... rescinded on December 16, 2010 in a letter from BPC, and this product should not have been cancelled...

  11. 19 CFR 113.54 - Cancellation of erroneous charges.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Cancellation of erroneous charges. 113.54 Section 113.54 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY CUSTOMS BONDS Assessment of Damages and Cancellation of Bond § 113.54 Cancellation of...

  12. Surgeon perception of cancellous screw fixation.

    Science.gov (United States)

    Stoesz, Michael J; Gustafson, Peter A; Patel, Bipinchandra V; Jastifer, James R; Chess, Joseph L

    2014-01-01

    The ability of surgeons to optimize screw insertion torque in nonlocking fixation constructs is important for stability, particularly in osteoporotic and cancellous bone. This study evaluated screw torque applied by surgeons during synthetic cancellous fixation. It evaluated the frequency with which screws were stripped by surgeons, factors associated with screw stripping, and ability of surgeons to recognize it. Ten surgeons assembled screw and plate fixation constructs into 3 densities of synthetic cancellous bone while screw insertion torque and axial force were measured. For each screw, the surgeon recorded a subjective rating as to whether or not the screw had been stripped. Screws were then advanced past stripping, and stripped screws were identified by comparing the insertion torque applied by the surgeon to the measured stripping torque. Surgeons stripped 109 (45.4%) of 240 screws and did not recognize stripping 90.8% of the time when it occurred. The tendency to strip screws was highly variable among individual surgeons (stripping ranging from 16.7% to 83.3%, P perception is not reliable at preventing and detecting screw stripping at clinical torque levels in synthetic cancellous bone. Less aggressive insertion or standardized methods of insertion may improve the stability of nonlocking screw and plate constructs.

  13. Heineman Prize Lecture: Anomaly Cancellation: A Retrospective

    Science.gov (United States)

    Schwarz, John

    2002-04-01

    The mechanism by which gauge and gravitational anomalies cancel in certain string theories is reviewed. A few new tricks are introduced to make the derivation a little simpler, and the string-theoretic interpretation a little clearer, than in the original 1984 work.

  14. Method for Canceling Ionospheric Doppler Effect

    Science.gov (United States)

    Vessot, R. F. C.

    1982-01-01

    Unified transponder system with hydrogen-maser oscillators at both stations can compensate for both motional and ionospheric components of Doppler shift. Appropriate choices of frequency shift in output of mixer m3. System exploits proportionality between dispersive component of frequency shift and reciprocal of frequency to achieve cancellation of dispersive component at output.

  15. Interference Cancellation System Design Using GNU Radio

    Science.gov (United States)

    2015-12-01

    Figures Fig. 1 Basic interference cancellation scheme .................................................1 Fig. 2 Ettus USRP B210...is available for free in Linux. The SDR chosen for testing is the universal software radio peripheral ( USRP ) B210 and is shown in Fig. 2...Approved for public release; distribution unlimited. 2 Fig. 2 Ettus USRP B210 According to Ettus Research, the B210 has the following

  16. Database Cancellation: The "Hows" and "Whys"

    Science.gov (United States)

    Shapiro, Steven

    2012-01-01

    Database cancellation is one of the most difficult tasks performed by a librarian. This may seem counter-intuitive but, psychologically, it is certainly true. When a librarian or a team of librarians has invested a great deal of time doing research, talking to potential users, and conducting trials before deciding to subscribe to a database, they…

  17. Amplifiers Exploiting Thermal Noise Canceling: A Review

    NARCIS (Netherlands)

    Klumperink, Eric A.M.; Bruccoleri, F.; Stroet, P.M.; Stroet, Peter; Nauta, Bram

    2004-01-01

    Wide-band LNAs suffer from a fundamental trade-off between noise figure NF and source impedance matching, which limits NF to values typically above 3dB. Recently, a feed-forward noise canceling technique has been proposed to break this trade-off. This paper reviews the principle of the technique and

  18. Thermal Noise Canceling in LNAs: A Review

    NARCIS (Netherlands)

    Nauta, Bram; Klumperink, Eric A.M.; Bruccoleri, F.

    2004-01-01

    Most wide-band amplifiers suffer from a fundamental trade-off between noise figure NF and source impedance matching, which limits NF to values typically above 3dB. Recently, a feed-forward noise canceling technique has been proposed to break this trade-off. This paper reviews the principle of the

  19. Elective surgery cancelation on day of surgery: An endless dilemma

    Directory of Open Access Journals (Sweden)

    A Fayed

    2016-01-01

    Full Text Available Background: Cancelation of surgery is a constant agonizing dilemma for nearly all healthcare services that has been intensively investigated to find out its roots, consequences, and possible solutions. The rates of cancelation of surgery vary between centers and more so among surgical specialties with numerous reasons standing behind this phenomenon. Patients and Methods: In the current study, analysis of monthly cancelation rates from January 2009 to December 2012, and assessment of establishing new operating rooms (ORs using statistical process control charts was conducted. A detailed review of a total of 1813 cases canceled on the day of surgery from January to December 2012, to examine the various reasons of cancelation among surgical specialties. Results: The average cancelation rate was 11.1%, which dropped to 9.0% after launching of new theaters. Four reasons explained about 80% of cancelations; Patients "no show" was the leading cause of cancelation (27%. One-fourth of cancelations (24.3% were due to the need for further optimization, and the third most prominent cause of cancelation was a lack of OR time (19.5%. Unavailability of staff/equipment/implants accounted for only 0.7% of cancelations. The "no show" was the most common cause of cancelation among all surgical specialties ranging from 21% for plastic surgery to 32% in ophthalmic surgeries. Conclusion: It was confirmed that there is a unique profile of cancelation of surgery problem for every institute, an extension of infrastructure may not be the only solution. Control charts helped to enhance the general picture and are functional in monitoring and evaluating changes in the cancelation of surgery.

  20. Elective surgery cancelation on day of surgery: An endless dilemma.

    Science.gov (United States)

    Fayed, A; Elkouny, A; Zoughaibi, N; Wahabi, H A

    2016-01-01

    Cancelation of surgery is a constant agonizing dilemma for nearly all healthcare services that has been intensively investigated to find out its roots, consequences, and possible solutions. The rates of cancelation of surgery vary between centers and more so among surgical specialties with numerous reasons standing behind this phenomenon. In the current study, analysis of monthly cancelation rates from January 2009 to December 2012, and assessment of establishing new operating rooms (ORs) using statistical process control charts was conducted. A detailed review of a total of 1813 cases canceled on the day of surgery from January to December 2012, to examine the various reasons of cancelation among surgical specialties. The average cancelation rate was 11.1%, which dropped to 9.0% after launching of new theaters. Four reasons explained about 80% of cancelations; Patients "no show" was the leading cause of cancelation (27%). One-fourth of cancelations (24.3%) were due to the need for further optimization, and the third most prominent cause of cancelation was a lack of OR time (19.5%). Unavailability of staff/equipment/implants accounted for only 0.7% of cancelations. The no show was the most common cause of cancelation among all surgical specialties ranging from 21% for plastic surgery to 32% in ophthalmic surgeries. It was confirmed that there is a unique profile of cancelation of surgery problem for every institute, an extension of infrastructure may not be the only solution. Control charts helped to enhance the general picture and are functional in monitoring and evaluating changes in the cancelation of surgery.

  1. Cloaking through cancellation of diffusive wave scattering

    KAUST Repository

    Farhat, Mohamed

    2016-08-10

    A new cloaking mechanism, which makes enclosed objects invisible to diffusive photon density waves, is proposed. First, diffusive scattering from a basic core-shell geometry, which represents the cloaked structure, is studied. The conditions of scattering cancellation in a quasi-static scattering regime are derived. These allow for tailoring the diffusivity constant of the shell enclosing the object so that the fields scattered from the shell and the object cancel each other. This means that the photon flow outside the cloak behaves as if the cloaked object were not present. Diffusive light invisibility may have potential applications in hiding hot spots in infrared thermography or tissue imaging. © 2016 The Author(s) Published by the Royal Society. All rights reserved.

  2. Modulation cancellation method (MOCAM) in modulation spectroscopy

    Science.gov (United States)

    Spagnolo, V.; Dong, L.; Kosterev, A. A.; Thomazy, D.; Doty, J. H.; Tittel, F. K.

    2011-05-01

    An innovative spectroscopic technique based on balancing and cancellation of modulated signals induced by two excitation sources. We used quartz enhanced photoacoustic spectroscopy (QEPAS) in a 2f wavelength modulation mode as an absorption sensing technique and employed a modulation cancelation approach for spectroscopic measurements of small temperature differences in a gas mixture and detection of broadband absorbers. We demonstrated measurement of small temperature differences in a C2H2/N2gas mixture with a sensitivity of 30 mK in 17 sec and detection of hydrazine, a broadband absorbing chemical species, down to concentration of 1 part per million in volume in 1 sec. In both cases we used near-infrared laser diodes and selected overtone transitions.nuscrip

  3. Noise Cancellation in ECG Signals using Computationally

    OpenAIRE

    D.V. Rama Koti Reddy; Mohammad Zia Ur Rahman; Rafi Ahamed Shaik

    2009-01-01

    Several signed LMS based adaptive filters, which are computationally superior having multiplier free weight update loops are proposed for noise cancellation in the ECG signal. The adaptive filters essentially minimizes the mean-squared error between a primary input, which is the noisy ECG, and a reference input, which is either noise that is correlated in some way with the noise in the primary input or a signal that is correlated only with ECG in the primary input. Different filter structures...

  4. Using Comics to Communicate Legal Contract Cancellation

    Directory of Open Access Journals (Sweden)

    Marietjie Botes

    2017-10-01

    Full Text Available This article investigates how comics can be used to adequately communicate the correct process of contract cancellation and whether comics can enhance understanding of the legal process. A survey of pre-owned vehicle buyers of various levels of education in Pretoria, South Africa found that when comics are used to communicate contract cancellation, a significant increase in the comprehension of the legal cancellation process occurs. The results may influence how contracting parties may choose to communicate complex legal issues in future, specifically to consumers with little formal education or when parties are confronted with severe language barriers, which is highly relevant in a country such as South Africa with eleven official languages and generally low levels of education. The article argues that representatives tasked with explaining contractual content to contracting parties should consider making use of comics to aid them in their communication process to ensure proper understanding and execution of terms and conditions, which in turn may lead to fewer disputes and avoid expensive litigation.

  5. SELF-CANCELLATION OF EPHEMERAL REGIONS IN THE QUIET SUN

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Shuhong; Zhang, Jun; Li, Ting [Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China); Liu, Yang, E-mail: shuhongyang@nao.cas.cn, E-mail: zjun@nao.cas.cn, E-mail: liting@nao.cas.cn, E-mail: yliu@sun.stanford.edu [W.W. Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305-4085 (United States)

    2012-06-20

    With the observations from the Helioseismic and Magnetic Imager aboard the Solar Dynamics Observatory, we statistically investigate the ephemeral regions (ERs) in the quiet Sun. We find that there are two types of ERs: normal ERs (NERs) and self-canceled ERs (SERs). Each NER emerges and grows with separation of its opposite polarity patches which will cancel or coalesce with other surrounding magnetic flux. Each SER also emerges and grows and its dipolar patches separate at first, but a part of the magnetic flux of the SER will move together and cancel gradually, which is described with the term 'self-cancellation' by us. We identify 2988 ERs, among which there are 190 SERs, about 6.4% of the ERs. The mean value of self-cancellation fraction of SERs is 62.5%, and the total self-canceled flux of SERs is 9.8% of the total ER flux. Our results also reveal that the higher the ER magnetic flux is, (1) the easier the performance of ER self-cancellation is, (2) the smaller the self-cancellation fraction is, and (3) the more the self-canceled flux is. We think that the self-cancellation of SERs is caused by the submergence of magnetic loops connecting the dipolar patches, without magnetic energy release.

  6. Three-dimensional microarchitecture of adolescent cancellous bone

    DEFF Research Database (Denmark)

    Ding, Ming; Danielsen, Carl Christian; Hvid, Ivan

    2012-01-01

    This study investigated microarchitectural, mechanical, collagen and mineral properties of normal adolescent cancellous bone, and compared them with adult and aging cancellous bone, to obtain more insight into the subchondral bone adaptations during development and growth. Twenty-three human...... proximal tibiae were harvested and divided into 3 groups according to their ages: adolescence (9 to 17years, n=6), young adult (18 to 24years, n=9), and adult (25 to 30years, n=8). Twelve cubic cancellous bone samples with dimensions of 8×8×8mm(3) were produced from each tibia, 6 from each medial......, the adolescent cancellous bone had similar bone volume fraction (BV/TV), structure type (plate, rod or mixtures), and connectivity (3-D trabecular networks) as the adult cancellous bone. The adolescent cancellous bone had significantly lower bone surface density (bone surface per total volume of specimen...

  7. Adaptive Noise Cancellation for speech Employing Fuzzy and Neural Network

    OpenAIRE

    Mohammed Hussein Miry; Ali Hussein Miry; Hussain Kareem Khleaf

    2011-01-01

    Adaptive filtering constitutes one of the core technologies in digital signal processing and finds numerous application areas in science as well as in industry. Adaptive filtering techniques are used in a wide range of applications such as noise cancellation. Noise cancellation is a common occurrence in today telecommunication systems. The LMS algorithm which is one of the most efficient criteria for determining the values of the adaptive noise cancellation coefficient...

  8. Evaluation Of Noise Cancellation Using LMS And NLMS Algorithm

    OpenAIRE

    Niti Gupta; Dr. Poonam Bansal

    2015-01-01

    This paper is focused on the adaptive noise cancellation of speech signal using the least mean square LMS and normalized least mean square method NLMS. Adaptive Noise Cancellation is an alternative way of cancelling noise present in a corrupted signal. In this technique evaluation of distorted signal by additive noise or interference achieved with no a priori estimates of signal or noise. A comparative study is carried out using LMS and NLSM methods. Result shows that these methods has potent...

  9. Evaluation Of Noise Cancellation Using LMS And NLMS Algorithm

    Directory of Open Access Journals (Sweden)

    Niti Gupta

    2015-08-01

    Full Text Available This paper is focused on the adaptive noise cancellation of speech signal using the least mean square LMS and normalized least mean square method NLMS. Adaptive Noise Cancellation is an alternative way of cancelling noise present in a corrupted signal. In this technique evaluation of distorted signal by additive noise or interference achieved with no a priori estimates of signal or noise. A comparative study is carried out using LMS and NLSM methods. Result shows that these methods has potential in noise cancellation and can be used for variety of applications.

  10. Flux Cancelation: The Key to Solar Eruptions

    Science.gov (United States)

    Panesar, Navdeep K.; Sterling, Alphonse; Moore, Ronald; Chakrapani, Prithi; Innes, Davina; Schmit, Don; Tiwari, Sanjiv

    2017-01-01

    Solar coronal jets are magnetically channeled eruptions that occur in all types of solar environments (e.g. active regions, quiet-Sun regions and coronal holes). Recent studies show that coronal jets are driven by the eruption of small-scare filaments (minifilaments). Once the eruption is underway magnetic reconnection evidently makes the jet spire and the bright emission in the jet base. However, the triggering mechanism of these eruptions and the formation mechanism of the pre-jet minifilaments are still open questions. In this talk, mainly using SDOAIA and SDOHIM data, first I will address the question: what triggers the jet-driving minifilament eruptions in different solar environments (coronal holes, quiet regions, active regions)? Then I will talk about the magnetic field evolution that produces the pre-jet minifilaments. By examining pre-jet evolutionary changes in line-of-sight HMI magnetograms while examining concurrent EUV images of coronal and transition-region emission, we find clear evidence that flux cancelation is the main process that builds pre-jet minifilaments, and is also the main process that triggers the eruptions. I will also present results from our ongoing work indicating that jet-driving minifilament eruptions are analogous to larger-scare filament eruptions that make flares and CMEs. We find that persistent flux cancellation at the neutral line of large-scale filaments often triggers their eruptions. From our observations we infer that flux cancelation is the fundamental process from the buildup and triggering of solar eruptions of all sizes.

  11. A new approach for cancelable iris recognition

    Science.gov (United States)

    Yang, Kai; Sui, Yan; Zhou, Zhi; Du, Yingzi; Zou, Xukai

    2010-04-01

    The iris is a stable and reliable biometric for positive human identification. However, the traditional iris recognition scheme raises several privacy concerns. One's iris pattern is permanently bound with him and cannot be changed. Hence, once it is stolen, this biometric is lost forever as well as all the applications where this biometric is used. Thus, new methods are desirable to secure the original pattern and ensure its revocability and alternatives when compromised. In this paper, we propose a novel scheme which incorporates iris features, non-invertible transformation and data encryption to achieve "cancelability" and at the same time increases iris recognition accuracy.

  12. Theory of diffusive light scattering cancellation cloaking

    CERN Document Server

    Farhat, Mohamed; Guenneau, Sebastien; Bagci, Hakan; Salama, Khaled Nabil; Alu, Andrea

    2016-01-01

    We report on a new concept of cloaking objects in diffusive light regime using the paradigm of the scattering cancellation and mantle cloaking techniques. We show numerically that an object can be made completely invisible to diffusive photon density waves, by tailoring the diffusivity constant of the spherical shell enclosing the object. This means that photons' flow outside the object and the cloak made of these spherical shells behaves as if the object were not present. Diffusive light invisibility may open new vistas in hiding hot spots in infrared thermography or tissue imaging.

  13. A new pathway for elective surgery to reduce cancellation rates

    DEFF Research Database (Denmark)

    Hovlid, Einar; Bukve, Oddbjørn; Haug, Kjell

    2012-01-01

    The cancellation of planned surgeries causes prolonged wait times, harm to patients, and is a waste of scarce resources. To reduce high cancellation rates in a Norwegian general hospital, the pathway for elective surgery was redesigned. The changes included earlier clinical assessment of patients...

  14. Reasons for cancellations of urologic day care surgery | Dakum ...

    African Journals Online (AJOL)

    Objective: The numerous economic and social benefits associated with the practice of day care surgery could be eroded by frequent cancellations. We therefore determined the reasons for such cancellations in a tertiary care centre in Nigeria. Patients and Methods: This was a prospective study of all consecutive urologic ...

  15. Reasons For Cancellation of Elective Paediatric Surgery Cases ...

    African Journals Online (AJOL)

    The bio-data on; clinical diagnosis and reasons for cancellation were documented. The study period was 18 months (March 2006- August 2007). Causes of cancellation were grouped into patients' factors (group A), parental factors (group B), and institutional factors (group C) There were 437 elective paediatric surgery ...

  16. Discovering Visual Scanning Patterns in a Computerized Cancellation Test

    Science.gov (United States)

    Huang, Ho-Chuan; Wang, Tsui-Ying

    2013-01-01

    The purpose of this study was to develop an attention sequential mining mechanism for investigating the sequential patterns of children's visual scanning process in a computerized cancellation test. Participants had to locate and cancel the target amongst other non-targets in a structured form, and a random form with Chinese stimuli. Twenty-three…

  17. Using Earned Value Information to Predict Program Cancellation

    Science.gov (United States)

    2014-09-02

    over 200 midshipmen. He became an Engineering Duty Officer in October 2008, completed the EDO Basic Course and his Engineering Duty Officer...Sample of Troubled Non-Cancelled Major Programs . 11 Table 3. Variables Used in Analysis ............................................................. 12...Hodgson, 2013) This study hypothesized that the variables presented in Table 3 were the most likely differentiators of cancelled programs. In

  18. 78 FR 14351 - Invasive Species Advisory Committee; Meeting Cancellation

    Science.gov (United States)

    2013-03-05

    ... Advisory Committee (ISAC) scheduled for Thursday, March 7, 2013 and Friday, March 8, 2013; is cancelled. The ISAC new member orientation scheduled for Wednesday, March 6, 2013 is also cancelled. Notice of....gov . SUPPLEMENTARY INFORMATION: The ISAC is comprised of 31 nonfederal invasive species experts and...

  19. Active noise canceling system for mechanically cooled germanium radiation detectors

    Science.gov (United States)

    Nelson, Karl Einar; Burks, Morgan T

    2014-04-22

    A microphonics noise cancellation system and method for improving the energy resolution for mechanically cooled high-purity Germanium (HPGe) detector systems. A classical adaptive noise canceling digital processing system using an adaptive predictor is used in an MCA to attenuate the microphonics noise source making the system more deployable.

  20. 77 FR 33203 - Equity and Excellence Commission, Meeting Cancellation

    Science.gov (United States)

    2012-06-05

    ... Equity and Excellence Commission, Meeting Cancellation AGENCY: U.S. Department of Education. ACTION... cancellation of the Meeting of the Equity and Excellence Commission scheduled for June 4, 2012 and announced in..., Equity and Excellence Commission, U.S. Department of Education, 400 Maryland Avenue SW., Washington, DC...

  1. 75 FR 51433 - Modifications of Debt Instruments; Hearing Cancellation

    Science.gov (United States)

    2010-08-20

    ... relating to the modification of debt instruments. DATES: The public hearing, originally scheduled for... Internal Revenue Service 26 CFR Part 1 RIN 1545-BJ30 Modifications of Debt Instruments; Hearing Cancellation AGENCY: Internal Revenue Service (IRS), Treasury. ACTION: Cancellation of notice of public hearing...

  2. 37 CFR 2.111 - Filing petition for cancellation.

    Science.gov (United States)

    2010-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Filing petition for cancellation. 2.111 Section 2.111 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT OF COMMERCE RULES OF PRACTICE IN TRADEMARK CASES Cancellation § 2.111 Filing petition for...

  3. 37 CFR 2.112 - Contents of petition for cancellation.

    Science.gov (United States)

    2010-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Contents of petition for cancellation. 2.112 Section 2.112 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT OF COMMERCE RULES OF PRACTICE IN TRADEMARK CASES Cancellation § 2.112 Contents of petition for...

  4. 78 FR 22846 - Smart Grid Advisory Committee Meeting Cancellation

    Science.gov (United States)

    2013-04-17

    ... National Institute of Standards and Technology Smart Grid Advisory Committee Meeting Cancellation AGENCY..., Smart Grid and Cyber-Physical Systems Program Office, National Institute of Standards and Technology... cancellation. SUMMARY: The meeting of the Smart Grid Advisory Committee (SGAC or Committee) scheduled for...

  5. 77 FR 5819 - Notice of Cancellation of Customs Broker Licenses

    Science.gov (United States)

    2012-02-06

    ... SECURITY U.S. Customs and Border Protection Notice of Cancellation of Customs Broker Licenses AGENCY: U.S... Border Protection regulations (19 CFR 111.51), the following Customs broker licenses and all associated permits are cancelled without prejudice. Name License No. Issuing port Neutral Customs Brokers, Inc...

  6. 77 FR 45647 - Notice of Cancellation of Customs Broker Licenses

    Science.gov (United States)

    2012-08-01

    ... Cancellation of Customs Broker Licenses AGENCY: U.S. Customs and Border Protection, U.S. Department of Homeland... Customs broker licenses and all associated permits are cancelled without prejudice. Name License No... 7 Seas Transport Logistics, Inc 23081 San Francisco. Liberty Port Broker, Inc 20911 New York. Sky...

  7. 78 FR 48456 - Notice of Cancellation of Customs Broker Licenses

    Science.gov (United States)

    2013-08-08

    ... SECURITY U.S. Customs and Border Protection Notice of Cancellation of Customs Broker Licenses AGENCY: U.S. Customs and Border Protection, Department of Homeland Security. ACTION: Customs broker license cancellations. SUMMARY: Notice is hereby given that the customs broker licenses and any and all associated...

  8. 76 FR 22912 - Notice of Cancellation of Customs Broker Licenses

    Science.gov (United States)

    2011-04-25

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HOMELAND SECURITY U.S. Customs and Border Protection Notice of Cancellation of Customs Broker Licenses AGENCY: U.S... CFR 111.51), the following Customs broker licenses and all associated permits are cancelled without...

  9. 21 CFR 1305.28 - Canceling and voiding electronic orders.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Canceling and voiding electronic orders. 1305.28 Section 1305.28 Food and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE ORDERS FOR SCHEDULE I AND II CONTROLLED SUBSTANCES Electronic Orders § 1305.28 Canceling and voiding electronic orders...

  10. Axial vector Z‧ and anomaly cancellation

    Science.gov (United States)

    Ismail, Ahmed; Keung, Wai-Yee; Tsao, Kuo-Hsing; Unwin, James

    2017-05-01

    Whilst the prospect of new Z‧ gauge bosons with only axial couplings to the Standard Model (SM) fermions is widely discussed, examples of anomaly-free renormalisable models are lacking in the literature. We look to remedy this by constructing several motivated examples. Specifically, we consider axial vectors which couple universally to all SM fermions, as well as those which are generation-specific, leptophilic, and leptophobic. Anomaly cancellation typically requires the presence of new coloured and charged chiral fermions, and we argue that in a large class of models masses of these new states are expected to be comparable to that of the axial vector. Finally, an axial vector mediator could provide a portal between SM and hidden sector states, and we also consider the possibility that the axial vector couples to dark matter. If the dark matter relic density is set due to freeze-out via the axial vector, this strongly constrains the parameter space.

  11. CERN Library - Journal cancellations in 2008

    CERN Multimedia

    2007-01-01

    In 2007, the CERN Library has been allocated a smaller budget than in 2006. Since subscriptions must be paid in advance, the current budget is being used to pay the journal collection for the year 2008 and is unfortunately not sufficient to maintain the information resources at the 2007 level. Consequently, the Working Group for Acquisitions (WGA) was obliged to identify candidates for cancellation for 2008. The list of candidates is shown here. As in the past, readers will be able to order articles from journals not available in the CERN Library through the Interlibrary Loan (ILL) service; generally articles are sent within 24h. Library users are invited to send comments on this proposal not later than 4 August 2007 to the WGA Chairman, Rudiger Voss, with a copy to the Head Librarian, Jens Vigen.

  12. Time Delay Estimation Algoritms for Echo Cancellation

    Directory of Open Access Journals (Sweden)

    Boris Simak

    2011-01-01

    Full Text Available The following case study describes how to eliminate echo in a VoIP network using delay estimation algorithms. It is known that echo with long transmission delays becomes more noticeable to users. Thus, time delay estimation, as a part of echo cancellation, is an important topic during transmission of voice signals over packetswitching telecommunication systems. An echo delay problem associated with IP-based transport networks is discussed in the following text. The paper introduces the comparative study of time delay estimation algorithm, used for estimation of the true time delay between two speech signals. Experimental results of MATLab simulations that describe the performance of several methods based on cross-correlation, normalized crosscorrelation and generalized cross-correlation are also presented in the paper.

  13. An Explicit Criterion for Adaptive Periodic Noise Canceller Robustness Applied to Feedback Cancellation

    OpenAIRE

    Timoney, Joseph; Foley, Brian; Schwarzbacher, A.

    2003-01-01

    This paper addresses the issue of robustness of an LMS-driven Adaptive Periodic Noise Canceller (APNC) in a closed-loop system. By adopting an analysis based on H-infinity theory, expressions are given under which the APNC, driven by the LMS algorithm, will exhibit robust performance properties. Simulation results are used to verify the analysis. Comparison is also made with an expression for stepsize derived for the less stringent bound of algorithm stability to demonstrate the stri...

  14. Causes for cancellation of aesthetic and reconstructive procedures.

    Science.gov (United States)

    Guyuron, B; Zarandy, S

    1993-09-01

    Cancellation of plastic surgical procedures has several deleterious effects, including emotional distress and economic ramifications. This prospective study, conducted over a 12-month period in a solo practice, reviewed the factors that contributed to surgical cancellations. Cancellations occurred despite many strict measures such as at least two preoperative visits, in-depth counseling and reinforcement by surgeon and staff, laboratory testing done 2 weeks prior to surgery, detailed evaluation of medical background, extensive written and verbal instructions to avoid medications that adversely affect surgery, and thorough discussion of payment plans and insurance coverage, including predetermination of any third-party coverage. Of the 952 patients (667 males, 285 females) scheduled for surgery, 113 experienced cancellation of the operation, either by the surgeon and staff or by the patient. Cancellations were proportionally fewer in male patients (p surgery, while 6 canceled for a second time. Thirty-two of the 113 canceled patients (28.3 percent) were patients in their fifth decade of life.(ABSTRACT TRUNCATED AT 250 WORDS)

  15. A journal cancellation survey and resulting impact on interlibrary loan.

    Science.gov (United States)

    Nash, Jacob L; McElfresh, Karen R

    2016-10-01

    The research describes an extensible method of evaluating and cancelling electronic journals during a budget shortfall and evaluates implications for interlibrary loan (ILL) and user satisfaction. We calculated cost per use for cancellable electronic journal subscriptions (n=533) from the 2013 calendar year and the first half of 2014, cancelling titles with cost per use greater than $20 and less than 100 yearly uses. For remaining titles, we issued an online survey asking respondents to rank the importance of journals to their work. Finally, we gathered ILL requests and COUNTER JR2 turnaway reports for calendar year 2015. Three hundred fifty-four respondents completed the survey. Because of the level of heterogeneity of titles in the survey as well as respondents' backgrounds, most titles were reported to be never used. We developed criteria based on average response across journals to determine which to cancel. Based on this methodology, we cancelled eight journals. Examination of ILL data revealed that none of the cancelled titles were requested with any frequency. Free-text responses indicated, however, that many value free ILL as a suitable substitute for immediate full-text access to biomedical journal literature. Soliciting user feedback through an electronic survey can assist collections librarians to make electronic journal cancellation decisions during slim budgetary years. This methodology can be adapted and improved upon at other health sciences libraries.

  16. Interference Management with Successive Cancellation for Dense Small Cell Networks

    DEFF Research Database (Denmark)

    Lopez, Victor Fernandez; Pedersen, Klaus I.; Steiner, Jens

    2016-01-01

    , known as Symbol-Level Interference Cancellation (SLIC), with respect to a baseline Minimum Mean Square Error-Interference Rejection Combining (MMSE-IRC) receiver. The study is carried out on a dense, clusterized small cell network, illustrating to which extent NAICS can overcome the additional......Network-Assisted Interference Cancellation and Suppression (NAICS) receivers have appeared as a promising way to curb inter-cell interference in future dense network deployments. This investigation compares the performance of a NAICS receiver with successive interference cancellation capabilities...

  17. Three-dimensional Microarchitecture of Adolescent Cancellous Bone

    DEFF Research Database (Denmark)

    Ding, Ming; Hvid, I; Overgaard, Søren

    during development and growth. We hypothesized that adolescent cancellous bone differed significantly from adult cancellous bone in their microarchitecture and mechanical properties. METHODS: Twenty-three human proximal tibiae were harvested and divided into 3 groups according to their ages: adolescence...... on cancellous bone collagen, mineralization and nanostructure. The results provide valuable information on bone development and growth, and are important for fracture repair, defect healing, biomaterial application, and pathogenesis of bone diseases in adolescence.......INTRODUCTION: The human skeleton optimizes its microarchitecture by elaborate adaptations to mechanical loading during development, growth and modeling. The mechanisms for adaptation involve a multistep process of cellular mechanotransduction stimulating bone modeling and remodeling resulting...

  18. A journal cancellation survey and resulting impact on interlibrary loan

    Directory of Open Access Journals (Sweden)

    Jacob L. Nash, MSLIS, AHIP

    2017-01-01

    Conclusions: Soliciting user feedback through an electronic survey can assist collections librarians to make electronic journal cancellation decisions during slim budgetary years. This methodology can be adapted and improved upon at other health sciences libraries.

  19. An Acoustic Echo Cancellation System based on Adaptive Algorithm

    OpenAIRE

    Garre, Veeratej; Mannem, Sailesh Kumar

    2012-01-01

    Adaptive filtering technique is one of the core technologies in digital signal processing and finds numerous application areas in science as well as in industry. Adaptive filtering technique is widely used in many applications, including echo cancellation, adaptive noise cancellation, adaptive beam forming and adaptive equalization. Acoustic echo is a common occurrence in today’s telecommunication systems. The distraction caused by the acoustic echo, reduces the speech quality in the communic...

  20. Adaptive cancellation of motion artifact in wearable biosensors.

    Science.gov (United States)

    Yousefi, Rasoul; Nourani, Mehrdad; Panahi, Issa

    2012-01-01

    The performance of wearable biosensors is highly influenced by motion artifact. In this paper, a model is proposed for analysis of motion artifact in wearable photoplethysmography (PPG) sensors. Using this model, we proposed a robust real-time technique to estimate fundamental frequency and generate a noise reference signal. A Least Mean Square (LMS) adaptive noise canceler is then designed and validated using our synthetic noise generator. The analysis and results on proposed technique for noise cancellation shows promising performance.

  1. ADAPTIVE NOISE CANCELLATION OF DOPPLER SHIFTED SIGNALS: A LINEAR FRAMEWORK

    OpenAIRE

    Stewart, R. W.; Weiss, S.

    1996-01-01

    In this paper we investigate the performance of single channel adaptive noise cancellation techniques for situations where the noise signal received by the two microphones cannot be related by a fixed weight canceller's (linear) digital filter due to Doppler shift on the two signals. A mathematical signal model is produced, which shows that the adaptive filter is in fact required to identify a time-varying system which incorporates Doppler shift, and potential rapid variations in signal power...

  2. Active noise control in a duct to cancel broadband noise

    Science.gov (United States)

    Chen, Kuan-Chun; Chang, Cheng-Yuan; Kuo, Sen M.

    2017-09-01

    The paper presents cancelling duct noises by using the active noise control (ANC) techniques. We use the single channel feed forward algorithm with feedback neutralization to realize ANC. Several kinds of ducts noises including tonal noises, sweep tonal signals, and white noise had investigated. Experimental results show that the proposed ANC system can cancel these noises in a PVC duct very well. The noise reduction of white noise can be up to 20 dB.

  3. Drag cancellation by added-mass pumping

    CERN Document Server

    Giorgio-Serchi, F

    2016-01-01

    A submerged body subject to a sudden shape-change experiences large forces due to the variation of added-mass energy. While this phenomenon has been studied for single actuation events, application to sustained propulsion requires studying \\textit{periodic} shape-change. We do so in this work by investigating a spring-mass oscillator submerged in quiescent fluid subject to periodic changes in its volume. We develop an analytical model to investigate the relationship between added-mass variation and viscous damping and demonstrate its range of application with fully coupled fluid-solid Navier-Stokes simulations at large Stokes number. Our results demonstrate that the recovery of added-mass kinetic energy can be used to completely cancel the viscous damping of the fluid, driving the onset of sustained oscillations with amplitudes as large as four times the average body radius $r_0$. A quasi-linear relationship is found to link the terminal amplitude of the oscillations $X$, to the extent of size change $a$, wit...

  4. IMPORTANT NOTICE: Cancellation of shuttle Circuit 3

    CERN Document Server

    2013-01-01

    Circuit 3 of the CERN Shuttle Service (Point 5), which has served CMS since the start of LS1, will be cancelled with effect from Tuesday 16 April. This decision has been taken in consultation with CMS, as the circuit was seldom used.   In response to increasing demand for Circuit 1 - Meyrin and feedback from passengers, the two Circuit 3 journeys will be switched to Circuit 1 – Meyrin (see new timetable below): Mornings: Four journeys instead of three. Circuit 1 now starts at 8:10 (instead of 8:19 a.m.) and runs until 9:27 a.m. (instead of 9:16 a.m.). Lunchtimes: Five journeys in place between 12:10 p.m. and 1:47 p.m. Evenings: Circuit starts at 5:23 p.m. (instead of 5:03 p.m.) and ends at 6:20 p.m. at Building 33. Please note that the circuit will depart from Building 13 instead of Building 33.  

  5. Invisibility and cloaking based on scattering cancellation.

    Science.gov (United States)

    Chen, Pai-Yen; Soric, Jason; Alù, Andrea

    2012-11-20

    Advances in material synthesis and in metamaterial technology offer new venues to tailor the electromagnetic properties of devices, which may go beyond conventional limits in a variety of fields and applications. Invisibility and cloaking are perhaps one of the most thought-provoking possibilities offered by these new classes of advanced materials. Here, recently proposed solutions for invisibility and cloaking using metamaterials, metasurfaces, graphene and/or plasmonic materials in different spectral ranges are reviewed and highlighted. The focus is primarily on scattering-cancellation approaches, describing material challenges, venues and opportunities for the plasmonic and the mantle cloaking techniques, applied to various frequency windows and devices. Analogies, potentials and relevant opportunities of these concepts are discussed, their potential realization and the underlying technology required to verify these phenomena are reviewed with an emphasis on the material aspects involved. Finally, these solutions are compared with other popular cloaking techniques. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Untwisting Jets Related to Magnetic Flux Cancellation

    Science.gov (United States)

    Liu, Jiajia; Erdélyi, Robert; Wang, Yuming; Liu, Rui

    2018-01-01

    The rotational motion of solar jets is believed to be a signature of the untwisting process resulting from magnetic reconnection, which takes place between twisted closed magnetic loops (i.e., magnetic flux ropes) and open magnetic field lines. The identification of the pre-existing flux rope, and the relationship between the twist contained in the rope and the number of turns the jet experiences, are then vital in understanding the jet-triggering mechanism. In this paper, we will perform a detailed analysis of imaging, spectral, and magnetic field observations of four homologous jets, among which the fourth one releases a twist angle of 2.6π. Nonlinear force-free field extrapolation of the photospheric vector magnetic field before the jet eruption presents a magnetic configuration with a null point between twisted and open fields—a configuration highly in favor of the eruption of solar jets. The fact that the jet rotates in the opposite sense of handness to the twist contained in the pre-eruption photospheric magnetic field confirms the unwinding of the twist by the jet’s rotational motion. The temporal relationship between jets’ occurrence and the total negative flux at their source region, together with the enhanced magnetic submergence term of the photospheric Poynting flux, shows that these jets are highly associated with local magnetic flux cancellation.

  7. A Microwave Photonic Interference Canceller: Architectures, Systems, and Integration

    Science.gov (United States)

    Chang, Matthew P.

    This thesis is a comprehensive portfolio of work on a Microwave Photonic Self-Interference Canceller (MPC), a specialized optical system designed to eliminate interference from radio-frequency (RF) receivers. The novelty and value of the microwave photonic system lies in its ability to operate over bandwidths and frequencies that are orders of magnitude larger than what is possible using existing RF technology. The work begins, in 2012, with a discrete fiber-optic microwave photonic canceller, which prior work had demonstrated as a proof-of-concept, and culminates, in 2017, with the first ever monolithically integrated microwave photonic canceller. With an eye towards practical implementation, the thesis establishes novelty through three major project thrusts. (Fig. 1): (1) Extensive RF and system analysis to develop a full understanding of how, and through what mechanisms, MPCs affect an RF receiver. The first investigations of how a microwave photonic canceller performs in an actual wireless environment and a digital radio are also presented. (2) New architectures to improve the performance and functionality of MPCs, based on the analysis performed in Thrust 1. A novel balanced microwave photonic canceller architecture is developed and experimentally demonstrated. The balanced architecture shows significant improvements in link gain, noise figure, and dynamic range. Its main advantage is its ability to suppress common-mode noise and reduce noise figure by increasing the optical power. (3) Monolithic integration of the microwave photonic canceller into a photonic integrated circuit. This thrust presents the progression of integrating individual discrete devices into their semiconductor equivalent, as well as a full functional and RF analysis of the first ever integrated microwave photonic canceller.

  8. Microwave Photonic Filters for Interference Cancellation and Adaptive Beamforming

    Science.gov (United States)

    Chang, John

    Wireless communication has experienced an explosion of growth, especially in the past half- decade, due to the ubiquity of wireless devices, such as tablets, WiFi-enabled devices, and especially smartphones. Proliferation of smartphones with powerful processors and graphic chips have given an increasing amount of people the ability to access anything from anywhere. Unfortunately, this ease of access has greatly increased mobile wireless bandwidth and have begun to stress carrier networks and spectra. Wireless interference cancellation will play a big role alongside the popularity of wire- less communication. In this thesis, we will investigate optical signal processing methods for wireless interference cancellation methods. Optics provide the perfect backdrop for interference cancellation. Mobile wireless data is already aggregated and transported through fiber backhaul networks in practice. By sandwiching the signal processing stage between the receiver and the fiber backhaul, processing can easily be done locally in one location. Further, optics offers the advantages of being instantaneously broadband and size, weight, and power (SWAP). We are primarily concerned with two methods for interference cancellation, based on microwave photonic filters, in this thesis. The first application is for a co-channel situation, in which a transmitter and receiver are co-located and transmitting at the same frequency. A novel analog optical technique extended for multipath interference cancellation of broadband signals is proposed and experimentally demonstrated in this thesis. The proposed architecture was able to achieve a maximum of 40 dB of cancellation over 200 MHz and 50 dB of cancellation over 10 MHz. The broadband nature of the cancellation, along with its depth, demonstrates both the precision of the optical components and the validity of the architecture. Next, we are interested in a scenario with dynamically changing interference, which requires an adaptive photonic

  9. Full-duplex wireless communications systems self-interference cancellation

    CERN Document Server

    Le-Ngoc, Tho

    2017-01-01

    This book introduces the development of self-interference (SI)-cancellation techniques for full-duplex wireless communication systems. The authors rely on estimation theory and signal processing to develop SI-cancellation algorithms by generating an estimate of the received SI and subtracting it from the received signal. The authors also cover two new SI-cancellation methods using the new concept of active signal injection (ASI) for full-duplex MIMO-OFDM systems. The ASI approach adds an appropriate cancelling signal to each transmitted signal such that the combined signals from transmit antennas attenuate the SI at the receive antennas. The authors illustrate that the SI-pre-cancelling signal does not affect the data-bearing signal. This book is for researchers and professionals working in wireless communications and engineers willing to understand the challenges of deploying full-duplex and practical solutions to implement a full-duplex system. Advanced-level students in electrical engineering and computer ...

  10. A new pathway for elective surgery to reduce cancellation rates

    Directory of Open Access Journals (Sweden)

    Hovlid Einar

    2012-06-01

    Full Text Available Abstract Background The cancellation of planned surgeries causes prolonged wait times, harm to patients, and is a waste of scarce resources. To reduce high cancellation rates in a Norwegian general hospital, the pathway for elective surgery was redesigned. The changes included earlier clinical assessment of patients, better planning and documentation systems, and increased involvement of patients in the scheduling of surgeries. This study evaluated the outcomes of this new pathway for elective surgery and explored which factors affected the outcomes. Methods We collected the number of planned operations, performed operations, and cancellations per month from the hospital’s patient administrative system. We then used Student's t-test to analyze differences in cancellation rates (CRs before and after interventions and a u-chart to analyze whether the improvements were sustained. We also conducted semi-structured interviews with employees of the hospital to explore the changes in the surgical pathway and the factors that facilitated these changes. Results The mean CR was reduced from 8.5% to 4.9% (95% CI for mean reduction 2.6-4.5, p p = 0.04. A clear improvement strategy, involvement of frontline clinicians, introduction of an electronic scheduling system, and engagement of middle managers were important factors for the success of the interventions. Conclusion The redesign of the old clinical pathway contributed to a sustained reduction in cancellations and an increased number of performed operations.

  11. Simulation for noise cancellation using LMS adaptive filter

    Science.gov (United States)

    Lee, Jia-Haw; Ooi, Lu-Ean; Ko, Ying-Hao; Teoh, Choe-Yung

    2017-06-01

    In this paper, the fundamental algorithm of noise cancellation, Least Mean Square (LMS) algorithm is studied and enhanced with adaptive filter. The simulation of the noise cancellation using LMS adaptive filter algorithm is developed. The noise corrupted speech signal and the engine noise signal are used as inputs for LMS adaptive filter algorithm. The filtered signal is compared to the original noise-free speech signal in order to highlight the level of attenuation of the noise signal. The result shows that the noise signal is successfully canceled by the developed adaptive filter. The difference of the noise-free speech signal and filtered signal are calculated and the outcome implies that the filtered signal is approaching the noise-free speech signal upon the adaptive filtering. The frequency range of the successfully canceled noise by the LMS adaptive filter algorithm is determined by performing Fast Fourier Transform (FFT) on the signals. The LMS adaptive filter algorithm shows significant noise cancellation at lower frequency range.

  12. [Primary cancellous bone formation around micro-chambered beads].

    Science.gov (United States)

    Draenert, M E; Draenert, Y; Draenert, K; Pohlemann, T; Erler, M

    2014-01-01

    The question has been raised whether benign bone defects in patients can be treated with bone forming osteoconductive ceramics achieving primarily a cancellous bone scaffold, which is under load from the beginning. Ten reconstructions were performed in 9patients (6women and 3male), with a mean age of 49 (25-65)years, suffering a high variety of epi- and metaphyseal defects, four tibial fractures, two calcaneal fractures, one pathological phalangeal fracture, one chondroma of the distal femur and two open-wedge osteotomies were filled with micro-chambered ceramic beads of 4 and 6mm in diameter. The mean follow up was 22 (7- 8)months. X-rays and CT-scans formed the basis for the evaluation of the reconstruction of the cancellous bone scaffolds. All cancellous structures were rebuilt, if completely filled with bone-forming elements. If the filling was incomplete, no physiological cancellous bone scaffold resulted. The β-TCP micro-chambered beads were completely reabsorbed or sandwich-like incorporated at the time of evaluation. The HA micro-chambered beads revealed a contrast enhancement and were integrated in the osseous construction of the bone scaffold. Primary cancellous bone formation can be achieved with osteoconductive ceramic micro-chambered beads and can be combined with any osteosynthesis for stable fixation. Copyright © 2013 SECOT. Published by Elsevier Espana. All rights reserved.

  13. Analysis of Intercarrier Interference Cancellation Scheme in OFDM Systems

    Directory of Open Access Journals (Sweden)

    Nasir Salh Almisbah

    2012-06-01

    Full Text Available Abstract: Orthogonal Frequency Division Multiplexing (OFDM is an emerging multi-carrier modulation scheme, which has been adopted for several wireless standards such as IEEE 802.11a and HiperLAN2. In OFDM systems, the performance is very sensitive to subcarrier frequency errors (offset. This paper shows the analysis and derivations of intercarrier interference (ICI complex gain that used in self-cancellation scheme and its dependence on subcarrier frequency offset. Simulation shows that better improvement in performance is achieved for systems that use this cancellation scheme. Moreover, analysis and simulation show that theoretical carrier-to-interference ratio (CIR for OFDM with cancellation scheme is greater than conventional one by more than 14dB.

  14. Interference Cancellation Using Space-Time Processing and Precoding Design

    CERN Document Server

    Li, Feng

    2013-01-01

    Interference Cancellation Using Space-Time Processing and Precoding Design introduces original design methods to achieve interference cancellation, low-complexity decoding and full diversity for a series of multi-user systems. In multi-user environments, co-channel interference will diminish the performance of wireless communications systems. In this book, we investigate how to design robust space-time codes and pre-coders to suppress the co-channel interference when multiple antennas are available.   This book offers a valuable reference work for graduate students, academic researchers and engineers who are interested in interference cancellation in wireless communications. Rigorous performance analysis and various simulation illustrations are included for each design method.   Dr. Feng Li is a scientific researcher at Cornell University.

  15. In vitro elution of moxifloxacin from cancellous bone allografts.

    Science.gov (United States)

    Kanellakopoulou, Kyriaki; Sahinides, Theophilos; Tsaganos, Thomas; Galanakis, Nearchos; Giamarellou, Helen; Giamarellos-Bourboulis, Evangelos J

    2010-01-01

    The characteristics of cancellous bone allografts as carriers of moxifloxacin are described. Particles of cancellous bone were compressed into a wire-mesh cylinder and impregnated into a solution of moxifloxacin for different time periods. Five replicas were impregnated for 1 h; another five for 24 h; and another five for 48 h. Impregnated allografts were then transferred into vials containing 5 ml of Mueller-Hinton broth and incubated at 37 degrees C. Broth was replaced daily. Concentrations of moxifloxacin in broth were determined after analysis by an high performance liquid chromatography system. Moxifloxacin was eluted at very high concentrations within the first days. Concentrations remained above 100 microg/ml until day 8 and above 40 microg/ml until day 20. It is concluded that cancellous bone allografts may allow the adequate in vitro elution of moxifloxacin. The latter results support their application in experimental models of osteomyelitis.

  16. Development of a Voice Activity Controlled Noise Canceller

    Directory of Open Access Journals (Sweden)

    Aini Hussain

    2012-05-01

    Full Text Available In this paper, a variable threshold voice activity detector (VAD is developed to control the operation of a two-sensor adaptive noise canceller (ANC. The VAD prohibits the reference input of the ANC from containing some strength of actual speech signal during adaptation periods. The novelty of this approach resides in using the residual output from the noise canceller to control the decisions made by the VAD. Thresholds of full-band energy and zero-crossing features are adjusted according to the residual output of the adaptive filter. Performance evaluation of the proposed approach is quoted in terms of signal to noise ratio improvements as well mean square error (MSE convergence of the ANC. The new approach showed an improved noise cancellation performance when tested under several types of environmental noise. Furthermore, the computational power of the adaptive process is reduced since the output of the adaptive filter is efficiently calculated only during non-speech periods.

  17. Cancellation Mechanism for Dark-Matter-Nucleon Interaction

    Science.gov (United States)

    Gross, Christian; Lebedev, Oleg; Toma, Takashi

    2017-11-01

    We consider a simple Higgs portal dark-matter model, where the standard model is supplemented with a complex scalar whose imaginary part plays the role of weakly interacting massive particle dark matter (DM). We show that the direct DM detection cross section vanishes at the tree level and zero momentum transfer due to a cancellation by virtue of a softly broken symmetry. This cancellation is operative for any mediator masses. As a result, our electroweak-scale dark matter satisfies all of the phenomenological constraints quite naturally.

  18. Cancellation Mechanism for Dark-Matter-Nucleon Interaction.

    Science.gov (United States)

    Gross, Christian; Lebedev, Oleg; Toma, Takashi

    2017-11-10

    We consider a simple Higgs portal dark-matter model, where the standard model is supplemented with a complex scalar whose imaginary part plays the role of weakly interacting massive particle dark matter (DM). We show that the direct DM detection cross section vanishes at the tree level and zero momentum transfer due to a cancellation by virtue of a softly broken symmetry. This cancellation is operative for any mediator masses. As a result, our electroweak-scale dark matter satisfies all of the phenomenological constraints quite naturally.

  19. 78 FR 51138 - Partial Cancellation of Fremont Grain Inspection Department Inc. Designation; Selection of...

    Science.gov (United States)

    2013-08-20

    ... Grain Inspection, Packers and Stockyards Administration Partial Cancellation of Fremont Grain Inspection... Area AGENCY: Grain Inspection, Packers and Stockyards Administration, USDA. ACTION: Notice. SUMMARY... the Grain Inspection, Packers and Stockyards Administration (GIPSA) that it wanted to cancel its...

  20. 78 FR 60280 - Good Neighbor Environmental Board; Cancellation Notice of Public Advisory Committee teleconference

    Science.gov (United States)

    2013-10-01

    ... AGENCY Good Neighbor Environmental Board; Cancellation Notice of Public Advisory Committee teleconference AGENCY: Environmental Protection Agency (EPA). ACTION: Cancellation of the Good Neighbor Environmental... Good Neighbor Environmental Board (GNEB) public teleconference. Pursuant to the Federal Advisory...

  1. 78 FR 72879 - Product Cancellation Order for Certain Pesticide Registrations; Correction

    Science.gov (United States)

    2013-12-04

    ... column (EPA Company No.), remove the entry: 1021. List of Subjects Environmental protection, Pesticides... AGENCY Product Cancellation Order for Certain Pesticide Registrations; Correction AGENCY: Environmental... September 20, 2013, concerning the product cancellation of several pesticide products, which were previously...

  2. 49 CFR 40.207 - What is the effect of a cancelled drug test?

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false What is the effect of a cancelled drug test? 40... TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Problems in Drug Tests § 40.207 What is the effect of a cancelled drug test? (a) A cancelled drug test is neither positive nor negative. (1) As an...

  3. 76 FR 15887 - Property Traded on an Established Market; Hearing Cancellation

    Science.gov (United States)

    2011-03-22

    ... purposes of determining the issue price of a debt instrument. DATES: The public hearing originally... Cancellation AGENCY: Internal Revenue Service (IRS), Treasury. ACTION: Cancellation of notice of public hearing on proposed rulemaking. SUMMARY: This document cancels a public hearing on a proposed rulemaking...

  4. 42 CFR 457.216 - Treatment of uncashed or canceled (voided) CHIP checks.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Treatment of uncashed or canceled (voided) CHIP... canceled (voided) CHIP checks. (a) Purpose. This section provides rules to ensure that States refund the... section— Canceled (voided) check means an CHIP check issued by a State or fiscal agent that prior to its...

  5. 49 CFR 40.273 - What is the effect of a cancelled alcohol test?

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false What is the effect of a cancelled alcohol test? 40... TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Problems in Alcohol Testing § 40.273 What is the effect of a cancelled alcohol test? (a) A cancelled alcohol test is neither positive nor negative. (1) As...

  6. 21 CFR 1305.19 - Cancellation and voiding of DEA Forms 222.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Cancellation and voiding of DEA Forms 222. 1305.19... I AND II CONTROLLED SUBSTANCES DEA Form 222 § 1305.19 Cancellation and voiding of DEA Forms 222. (a) A purchaser may cancel part or all of an order on a DEA Form 222 by notifying the supplier in...

  7. Canceling Some d-CON Mouse and Rat Control Products

    Science.gov (United States)

    EPA has reached agreement with the manufacturer, to cancel 12 d-CON products that do not meet our testing protocols that better protect children, pets and non-target wildlife from accidental exposure to the pesticide. These products will be phased out.

  8. The Generalized Optic Acceleration Cancellation Theory of Catching

    Science.gov (United States)

    McLeod, Peter; Reed, Nick; Dienes, Zoltan

    2006-01-01

    The generalized optic acceleration cancellation (GOAC) theory of catching proposes that the path of a fielder running to catch a ball is determined by the attempt to satisfy 2 independent constraints. The 1st is to keep the angle of elevation of gaze to the ball increasing at a decreasing rate. The 2nd is to control the rate of horizontal rotation…

  9. 7 CFR 301.87-6 - Compliance agreement; cancellation.

    Science.gov (United States)

    2010-01-01

    ... regulated articles under this subpart. 7 The compliance agreement shall be a written agreement between a... in telephone directories.) (b) Any compliance agreement may be canceled orally or in writing by the inspector who is supervising its enforcement whenever the inspector finds that such person has failed to...

  10. 77 FR 50702 - Cardiovascular and Renal Drugs Advisory Committee; Cancellation

    Science.gov (United States)

    2012-08-22

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration Cardiovascular and Renal Drugs Advisory Committee... Cardiovascular and Renal Drugs Advisory Committee scheduled for September 14, 2012, is cancelled. The meeting is...

  11. Laboratory Investigation of Noise-Canceling Headphones Utilizing "Mr. Blockhead"

    Science.gov (United States)

    Koser, John

    2013-01-01

    While I was co-teaching an introductory course in musical acoustics a few years ago, our class investigated several pieces of equipment designed for audio purposes. One piece of such equipment was a pair of noise-canceling headphones. Our students were curious as to how these devices were in eliminating background noise and whether they indeed…

  12. 75 FR 81283 - Oncologic Drugs Advisory Committee; Cancellation

    Science.gov (United States)

    2010-12-27

    ... HUMAN SERVICES Food and Drug Administration Oncologic Drugs Advisory Committee; Cancellation AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The meeting of the Oncologic Drugs Advisory... of December 6, 2010 (75 FR 75680). On February 9, 2011, the Oncologic Drugs Advisory Committee was...

  13. Revenue Management under Customer Choice Behaviour with Cancellations and Overbooking

    NARCIS (Netherlands)

    D.D. Sierag (Dirk); G.M. Koole (Ger); R.D. van der Mei (Rob); JP.I. van der Rest (Jean-Pierre); A.P. Zwart (Bert)

    2015-01-01

    htmlabstractRevenue management is the practice of pricing perishable goods to optimise revenue. A realistic revenue management model allows overbooking and incorporates customer buying behaviour and cancellations. The latter is motivated by our research using real data, which shows that for a

  14. Software defined radio receivers exploiting noise cancelling: A tutorial review

    NARCIS (Netherlands)

    Klumperink, Eric A.M.; Nauta, Bram

    2014-01-01

    Traditional radio receivers were narrowband and dedicated to a single frequency band exploiting LC tanks, whereas software defined radios target a flexibly programmable frequency. The broadband noise cancelling circuit technique has proven useful to achieve this target, as it breaks the traditional

  15. 7 CFR 301.51-6 - Compliance agreements and cancellation.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false Compliance agreements and cancellation. 301.51-6 Section 301.51-6 Agriculture Regulations of the Department of Agriculture (Continued) ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE DOMESTIC QUARANTINE NOTICES Asian Longhorned Beetle...

  16. Cosserat moduli of anisotropic cancellous bone : A micromechanical analysis

    NARCIS (Netherlands)

    Fatemi, J.; Onck, P.R.; Poort, G.; Van Keulen, F.

    A micromechanical-based approach is proposed to quantify the effective (in the macroscopic sense) elastic constants of Cosserat materials. The material under investigation (cancellous bone) is cellular and classically elastic at the microscopic level and assumed to be dense Cosserat elastic at the

  17. Reasons for cancellation of elective surgery in Ilorin | Kolawole ...

    African Journals Online (AJOL)

    Cancellation of cases on the scheduled day of surgery leads to inefficient utilization of theatre space, waste of valuable manpower and scarce resources for ... from surgery for personal reasons not communicated to the Surgeons in 13.60% of cases, while unanticipated logistic problems accounted for another 9.93%.

  18. 77 FR 63839 - Oncologic Drugs Advisory Committee; Cancellation

    Science.gov (United States)

    2012-10-17

    ... HUMAN SERVICES Food and Drug Administration Oncologic Drugs Advisory Committee; Cancellation AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The meeting of the Oncologic Drugs Advisory... committee have been resolved. FOR FURTHER INFORMATION CONTACT: Caleb Briggs, Center for Drug Evaluation and...

  19. 19 CFR 10.64 - Crediting or cancellation of bonds.

    Science.gov (United States)

    2010-04-01

    ... chapter may be credited or canceled in respect of such articles upon the vessel's departure from the port of lading in a class of trade or business entitling the articles to exemption from duty and tax under... OF THE TREASURY ARTICLES CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. General Provisions...

  20. Neutrosophic Duplet Semi-Group and Cancellable Neutrosophic Triplet Groups

    Directory of Open Access Journals (Sweden)

    Xiaohong Zhang

    2017-11-01

    Full Text Available The notions of the neutrosophic triplet and neutrosophic duplet were introduced by Florentin Smarandache. From the existing research results, the neutrosophic triplets and neutrosophic duplets are completely different from the classical algebra structures. In this paper, we further study neutrosophic duplet sets, neutrosophic duplet semi-groups, and cancellable neutrosophic triplet groups. First, some new properties of neutrosophic duplet semi-groups are funded, and the following important result is proven: there is no finite neutrosophic duplet semi-group. Second, the new concepts of weak neutrosophic duplet, weak neutrosophic duplet set, and weak neutrosophic duplet semi-group are introduced, some examples are given by using the mathematical software MATLAB (MathWorks, Inc., Natick, MA, USA, and the characterizations of cancellable weak neutrosophic duplet semi-groups are established. Third, the cancellable neutrosophic triplet groups are investigated, and the following important result is proven: the concept of cancellable neutrosophic triplet group and group coincide. Finally, the neutrosophic triplets and weak neutrosophic duplets in BCI-algebras are discussed.

  1. 76 FR 63656 - Front Range Resource Advisory Council Meeting Cancellation

    Science.gov (United States)

    2011-10-13

    ...] Front Range Resource Advisory Council Meeting Cancellation AGENCY: Bureau of Land Management, Interior... Front Range Resource Advisory Council meeting scheduled for October 19, 2011 at the BLM Royal Gorge....m. to 4:30 p.m. FOR FURTHER INFORMATION CONTACT: Tina Brown, Front Range RAC Coordinator, BLM...

  2. 41 CFR 101-28.306-4 - Expiration or cancellation.

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Expiration or cancellation. 101-28.306-4 Section 101-28.306-4 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS SUPPLY AND PROCUREMENT 28-STORAGE AND...

  3. Imperfect generalized transmit beamforming with co-channel interference cancelation

    KAUST Repository

    Radaydeh, Redha Mahmoud Mesleh

    2010-10-01

    The performance of a generalized single-stream transmit beamforming scheme employing receive co-channel interference -steering algorithms in slowly varying and flat fading channels is analyzed. The impact of imperfect prediction of channel state information (CSI) for the desired user spatially uncorrelated transmit channels is considered. Both dominant interference cancelation and adaptive arbitrary interference cancelation algorithms for closely spaced receive antennas are used. The impact of outdated statistical ordering of the interferers instantaneous powers on the effectiveness of dominant interference cancelation is investigated against the less complex adaptive arbitrary cancelation scheme. For the system models described above, new exact formulas for the statistics of combined signal-to-interference-plus-noise ratio (SINR) are derived, from which results for conventional maximum ratio transmission (MRT) and best transmit channel selection schemes can be deduced as limiting cases. The results presented herein can be used to obtain quantitative measure for various performance metrics, and in addition to investigate the performance-complexity tradeoff for different multiple-antenna system models. © 2010 IEEE.

  4. 38 CFR 3.1003 - Returned and canceled checks.

    Science.gov (United States)

    2010-07-01

    ... provisions of this section do not apply to checks for lump sums representing amounts withheld under § 3.551(b... checks. 3.1003 Section 3.1003 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS... canceled checks. Where the payee of a check for benefits has died prior to negotiating the check, the check...

  5. Canceling out Both the Real and the Spectral Lines

    Science.gov (United States)

    Toraldo, A.; Gandola, M.; Loffredo, S.; Rancati, A.; Zanardi, G.; Bottini, G.

    2005-01-01

    Neglect patients typically show motor perseveration while canceling targets on the ipsilesional side. This behavior can be influenced by the presence vs. absence of targets on the (neglected) contralesional side (Bottini & Toraldo, 2003). As alternative explanations, the authors proposed (i) directional hypokinesia-the patient cannot perform…

  6. Analysing Self Interference Cancellation in Full Duplex Radios

    DEFF Research Database (Denmark)

    Mahmood, Nurul Huda; Shafique Ansari, Imran; Berardinelli, Gilberto

    2016-01-01

    cancellation. In this study, we derive an analytical model for the residual self interference power, and demonstrate various applications of the derived model in analysing the performance of a Full Duplex radio. In general, full duplex communication is found to provide only modest throughput gains over half...

  7. Clinical Utility of Cancellation on the WISC-IV

    Science.gov (United States)

    Zhu, Jianjun; Chen, Hsinyi

    2013-01-01

    This study examined empirical evidence for clinical utility of the Wechsler Intelligence Scale for Children, fourth edition (WISC-IV) cancellation subtest by comparing data from 597 clinical and 597 matched control children. The results of dependent t and sequential logistic regression analyses demonstrated that (a) children with intellectual…

  8. Reward Improves Cancellation and Restraint Inhibition across Childhood and Adolescence

    Science.gov (United States)

    Sinopoli, Katia J.; Schachar, Russell; Dennis, Maureen

    2011-01-01

    Inhibitory control allows for the regulation of thought and action and interacts with motivational variables, such as reward, to modify behavior adaptively as environments change. The authors examined the effects of reward on two distinct forms of inhibitory control, cancellation and restraint. Typically developing children and adolescents…

  9. 37 CFR 201.7 - Cancellation of completed registrations.

    Science.gov (United States)

    2010-07-01

    ... reasons therefor, and be given 30 days, from the date the Copyright Office letter is mailed, to show cause in writing why the cancellation should not be made. If the claimant fails to respond within the 30... in error and not in accordance with title 17 U.S.C., Chapters 1 through 8, the registration will be...

  10. Cancellation of global anomalies in spontaneously broken gauge ...

    Indian Academy of Sciences (India)

    the Higgs phase of a gauge theory [6]. The would-be Goldstone bosons—the angular components of the Higgs field—are the scalar fields that can be used to write the WZ term. This idea had already been put forward in [7] where the interplay between renormalizability and anomaly cancellation in spontaneously broken ...

  11. Cancellation of Indigenous Australians from the Apprenticeship Training Contract

    Science.gov (United States)

    Mangan, John; Trendle, Bernard

    2010-01-01

    The vocational education and training (VET) sector is a major pathway to post-school education for indigenous students, yet questions are being raised about the capacity of the VET system to provide successful outcomes for the indigenous apprentices and trainees it attracts. Within a system plagued by high cancellation rates in general, indigenous…

  12. 75 FR 47825 - Notice of Cancellation of Customs Broker License

    Science.gov (United States)

    2010-08-09

    ... SECURITY U.S. Customs and Border Protection Notice of Cancellation of Customs Broker License AGENCY: U.S... Border Protection regulations (19 CFR 111.51(b)), the following Customs broker licenses and all... Customs Broker & 20090 Miami. Forwarders, Inc.. Dated: July 27, 2010. Daniel Baldwin, Assistant...

  13. 76 FR 13205 - Notice of Cancellation of Customs Broker Licenses

    Science.gov (United States)

    2011-03-10

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HOMELAND SECURITY U.S. Customs and Border Protection Notice of Cancellation of Customs Broker Licenses AGENCY: U.S... Border Protection regulations (19 CFR 111.45), the following Customs broker licenses and all associated...

  14. 76 FR 7873 - Notice of Cancellation of Customs Broker License

    Science.gov (United States)

    2011-02-11

    ... From the Federal Register Online via the Government Publishing Office ] DEPARTMENT OF HOMELAND SECURITY Customs and Border Protection Notice of Cancellation of Customs Broker License AGENCY: U.S... Border Protection regulations (19 CFR 111.51(b)), the following Customs broker license and all associated...

  15. 75 FR 76998 - Notice of Cancellation of Customs Broker Licenses

    Science.gov (United States)

    2010-12-10

    ... SECURITY U.S. Customs and Border Protection Notice of Cancellation of Customs Broker Licenses AGENCY: U.S... Border Protection regulations (19 CFR 111.51), the following Customs broker licenses and all associated.... GEMM Customs Brokers, Inc 09879 New York. Richard Penack 09782 New York. G.W. Harder Company, Inc 24177...

  16. 77 FR 43609 - Notice of Cancellation of Customs Broker Licenses

    Science.gov (United States)

    2012-07-25

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HOMELAND SECURITY U.S. Customs and Border Protection Notice of Cancellation of Customs Broker Licenses AGENCY: U.S... Border Protection regulations (19 CFR 111.53), the following Customs broker license and all associated...

  17. 77 FR 74022 - Notice of Cancellation of Customs Broker License

    Science.gov (United States)

    2012-12-12

    ... From the Federal Register Online via the Government Publishing Office ] DEPARTMENT OF HOMELAND SECURITY U.S. Customs and Border Protection Notice of Cancellation of Customs Broker License AGENCY: U.S... Border Protection regulations (19 CFR 111.51), the following Customs broker license and all associated...

  18. 76 FR 44032 - Notice of Cancellation of Customs Broker Licenses

    Science.gov (United States)

    2011-07-22

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HOMELAND SECURITY U.S. Customs and Border Protection Notice of Cancellation of Customs Broker Licenses AGENCY: U.S... Border Protection regulations (19 CFR 111.51), the following Customs broker licenses and all associated...

  19. 75 FR 75691 - Notice of Cancellation of Customs Broker License

    Science.gov (United States)

    2010-12-06

    ... SECURITY U.S. Customs and Border Protection Notice of Cancellation of Customs Broker License AGENCY: U.S... Border Protection regulations (19 CFR 111.45), the following Customs broker license and all associated permits are revoked with prejudice. License Name No. Issuing port Foreign Cargo Customs Brokers, Inc...

  20. 75 FR 11898 - Notice of Cancellation of Customs Broker License

    Science.gov (United States)

    2010-03-12

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HOMELAND SECURITY U.S. Customs and Border Protection Notice of Cancellation of Customs Broker License AGENCY: U.S... Border Protection regulations (19 CFR 111.51(b)), the following Customs broker license and all associated...

  1. 77 FR 16249 - Notice of Cancellation of Customs Broker Licenses

    Science.gov (United States)

    2012-03-20

    ... SECURITY U.S. Customs and Border Protection Notice of Cancellation of Customs Broker Licenses AGENCY: U.S... Border Protection regulations (19 CFR 111.51), the following Customs broker licenses and all associated... 12574 New Orleans. and Transport, Inc.. Professional Customs Brokers, Inc 22821 San Juan. BAX Global...

  2. 75 FR 47825 - Notice of Cancellation of Customs Broker Licenses

    Science.gov (United States)

    2010-08-09

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HOMELAND SECURITY U.S. Customs and Border Protection Notice of Cancellation of Customs Broker Licenses AGENCY: U.S... Border Protection regulations (19 CFR 111.51), the following Customs broker license and all associated...

  3. 75 FR 5618 - Notice of Cancellation of Customs Broker License

    Science.gov (United States)

    2010-02-03

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HOMELAND SECURITY U.S. Customs and Border Protection Notice of Cancellation of Customs Broker License AGENCY: U.S... Border Protection regulations (19 CFR 111.51(b)), the following Customs broker license and all associated...

  4. 75 FR 11899 - Notice of Cancellation of Customs Broker Licenses

    Science.gov (United States)

    2010-03-12

    ... SECURITY U.S. Customs and Border Protection Notice of Cancellation of Customs Broker Licenses AGENCY: U.S... Border Protection regulations (19 CFR 111.51), the following Customs broker licenses and all associated.... American Customs Brokers Co., Inc... 04578 Los Angeles. Import Brokers, Inc 06291 Miami. Bridgeport Customs...

  5. 76 FR 2918 - Notice of Cancellation of Customs Broker Licenses

    Science.gov (United States)

    2011-01-18

    ... SECURITY U.S. Customs and Border Protection Notice of Cancellation of Customs Broker Licenses AGENCY: U.S... Border Protection regulations (19 CFR 111.51), the following Customs broker licenses and all associated... & Lorbacher, Inc 01135 New York Gallop Fargo Customs Brokers, Inc 27658 Los Angeles Dated: January 4, 2011...

  6. 76 FR 4686 - Product Cancellation Order for Certain Pesticide Registrations

    Science.gov (United States)

    2011-01-26

    ...--Product Cancellations Active Registration No. Product name ingredients 000004-00059 Bonide Rose & Flower... Crawling Insect 264 Permethrin. Killer. 000498-00170 Spraypak Wasp & d-Allethrin Hornet Killer, Phenothrin... Butoxide Concentrate. Pyrethrins. 010807-00003 Misty Blaster Insect MGK 264 Piperonyl Spray. Butoxide...

  7. Interference Cancelation Schemes for Uplink Transmission in Femtocells

    DEFF Research Database (Denmark)

    Thai, Chan; Popovski, Petar

    2010-01-01

    We present techniques that solve the near-far problems in femtocell networks. When a co-channel configuration is used, a transmission in the macrocell may cause interference to a femtocell. We introduce methods to cancel the interference caused by the macrocell to a femtocell by using the high-ra...

  8. Design And Simulation Of An Acoustic Echo Cancellation System For Hand-Free Telecommunication

    Directory of Open Access Journals (Sweden)

    Ein Gyin Pwint

    2015-06-01

    Full Text Available Abstract Acoustic echo cancellation is a common occurrence in todays telecommunication systems. The signal interference caused by acoustic echo is distracting to users and causes a reduction in the quality of the communication. This paper is implementing the overall system of acoustic echo cancellation system using LMS and NLMS algorithms for adaptive filter normalized cross correlation NCC algorithm double talk detector. The result of echo return loss enhancement ERLE and mean squared error MSE which show that how much the amount of echo signal cancelled and the amount of residual error signal for cancelling acoustic echo cancellation on a PC with the help of the MATLAB software.

  9. Factors impacting same-day cancellation of outpatient pediatric magnetic resonance imaging under anesthesia

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, Andrea S. [University of Toronto, Department of Paediatrics, Division of Developmental Paediatrics, Holland Bloorview Kids Rehabilitation Hospital, Toronto (Canada); Matlow, Anne [University of Toronto, Strategic Initiatives, Postgraduate Medical Education, Toronto (Canada); Shroff, Manohar [University of Toronto, Department of Diagnostic Imaging, Division of Neuroradiology, Hospital for Sick Children, Toronto (Canada); Cohen, Eyal [University of Toronto, Division of Paediatric Medicine and Child Health Evaluative Sciences, Hospital for Sick Children, Department of Paediatrics and Institute of Health Policy, Management and Evaluation, Toronto (Canada)

    2014-07-24

    Studies of elective surgical procedures indicate that cancellation is common and preventable. Little is known about cancellation of anesthesia-supported elective diagnostic imaging. To describe the reasons for same-day cancellation of MRI studies performed under sedation or anesthesia and identify patient characteristics associated with cancellations. This case-control study was carried out in a university-affiliated tertiary care children's hospital. Cases were defined as elective outpatient MRI studies booked under anesthesia that were cancelled after the patient had arrived in the radiology department in 2009. Matched controls were identified by selecting the same day and time 1 week before or after the cancelled case. Main outcome measures included demographics, MRI study characteristics, and social and medical factors. There were 111 outpatient anesthesia-supported MRI studies cancelled on the same day as the assessment (cancellation rate: 4.5%), of which 74.6% were related to family and patient factors, while 22% were related to system factors. Cancelled cases involved patients who lived in lower median income quintile neighborhoods compared to controls (2 vs. 3; P = 0.0007; odds ratio [OR] 3.81; 95% confidence interval [CI] 1.18-12.34). Those who traveled a greater median distance (in kilometers) were less likely to be cancelled (18.8 vs. 27.1, P = 0.0035). Although cancelled patients had a lower mean number of total medical services (2.5 vs. 3.0; P = 0.03; OR = 0.78; 95% CI 0.62-0.98), current medical factors (past 12 months) did not impact cancellations. Same-day cancellations of anesthesia-supported MRI studies are not uncommon, and the main predictor of cancellation seems to be socioeconomic rather than medical. (orig.)

  10. A Study on the Frequency and the Reasons for Cancellation of Surgical Operations in Khatam Hospital (Mashhad, Iran in 2013

    Directory of Open Access Journals (Sweden)

    Hossein Ebrahimipour

    2014-10-01

    Conclusion: In a high percentage of canceled cases, the reasons of operation cancellations had not been mentioned in the patient’s file. A significant portion of theses cancellations can be attributed to the patients' incomplete cooperation.  Cancellations can be significantly reduced through providing the patient with enough instructions and explanations.

  11. Coarse-fine residual gravity cancellation system with magnetic levitation

    Science.gov (United States)

    Salcudean, S. E.; Davis, H.; Chen, C. T.; Goertz, D. E.; Tryggvason, B. V.

    1992-01-01

    Aircraft flight along parabolic trajectories have been proposed and executed in order to achieve low cost, near free fall conditions of moderate duration. This paper describes a six degree of freedom experiment isolation system designed to cancel out residual accelerations due to mechanical vibrations and errors in aircraft trajectory. The isolation system consists of a fine motion magnetic levitator whose stator is transported by a conventional coarse motion stage. The levitator uses wide gap voice coil actuators and has the dual purpose of isolating the experiment platform from aircraft vibrations and actively cancelling residual accelerations through feedback control. The course motion stage tracks the levitated platform in order to keep the levitator's coils centered within their matching magnetic gaps. Aspects of system design, an analysis of the proposed control strategy and simulation results are presented. Feasibility experiments are also discussed.

  12. Experimental testing of the noise-canceling processor.

    Science.gov (United States)

    Collins, Michael D; Baer, Ralph N; Simpson, Harry J

    2011-09-01

    Signal-processing techniques for localizing an acoustic source buried in noise are tested in a tank experiment. Noise is generated using a discrete source, a bubble generator, and a sprinkler. The experiment has essential elements of a realistic scenario in matched-field processing, including complex source and noise time series in a waveguide with water, sediment, and multipath propagation. The noise-canceling processor is found to outperform the Bartlett processor and provide the correct source range for signal-to-noise ratios below -10 dB. The multivalued Bartlett processor is found to outperform the Bartlett processor but not the noise-canceling processor. © 2011 Acoustical Society of America

  13. Canceling disorder-induced localization in nanophotonic cavity arrays

    CERN Document Server

    Sokolov, Sergei; Yüce, Emre; Combrié, Sylvain; De Rossi, Alfredo; Mosk, Allard P

    2016-01-01

    Optical circuits containing high-Q photonic crystal nanocavities have been proposed for delay lines, optical memory storage, optomechanics and quantum communication. However, unavoidable fabrication disorder in nanophotonic structures causes scattering which leads to frequency detuning, signal attenuation, and eventually localizes optical modes which ruins the transmission properties of the whole system. Even state-of-the-art nanofabrication with random spatial variations of only $\\Delta x=1\\ \\rm{nm}$ can lead to resonance wavelength detunings of more than $\\Delta \\lambda =1\\ \\rm{nm}$. In this work, we present a new method to cancel disorder-induced localization of light in a system of coupled nanocavities. We use holographic laser-induced heating to tune individual cavities, introduce a thermal response matrix approach and as a result we observe fully hybridized resonances of three coupled nanocavities, indicating that the effect of the disorder has been canceled. Our method is scalable to large arrays and e...

  14. A cancelable biometric scheme based on multi-lead ECGs.

    Science.gov (United States)

    Peng-Tzu Chen; Shun-Chi Wu; Jui-Hsuan Hsieh

    2017-07-01

    Biometric technologies offer great advantages over other recognition methods, but there are concerns that they may compromise the privacy of individuals. In this paper, an electrocardiogram (ECG)-based cancelable biometric scheme is proposed to relieve such concerns. In this scheme, distinct biometric templates for a given beat bundle are constructed via "subspace collapsing." To determine the identity of any unknown beat bundle, the multiple signal classification (MUSIC) algorithm, incorporating a "suppression and poll" strategy, is adopted. Unlike the existing cancelable biometric schemes, knowledge of the distortion transform is not required for recognition. Experiments with real ECGs from 285 subjects are presented to illustrate the efficacy of the proposed scheme. The best recognition rate of 97.58 % was achieved under the test condition Ntrain = 10 and Ntest = 10.

  15. Active cancellation of probing in linear dipole phased array

    CERN Document Server

    Singh, Hema; Jha, Rakesh Mohan

    2015-01-01

    In this book, a modified improved LMS algorithm is employed for weight adaptation of dipole array for the generation of beam pattern in multiple signal environments. In phased arrays, the generation of adapted pattern according to the signal scenario requires an efficient adaptive algorithm. The antenna array is expected to maintain sufficient gain towards each of the desired source while at the same time suppress the probing sources. This cancels the signal transmission towards each of the hostile probing sources leading to active cancellation. In the book, the performance of dipole phased array is demonstrated in terms of fast convergence, output noise power and output signal-to-interference-and noise ratio. The mutual coupling effect and role of edge elements are taken into account. It is established that dipole array along with an efficient algorithm is able to maintain multilobe beamforming with accurate and deep nulls towards each probing source. This work has application to the active radar cross secti...

  16. Active cancellation of acoustical resonances with an FPGA FIR filter

    Science.gov (United States)

    Ryou, Albert; Simon, Jonathan

    2017-01-01

    We present a novel approach to enhancing the bandwidth of a feedback-controlled mechanical system by digitally canceling acoustical resonances (poles) and anti-resonances (zeros) in the open-loop response via an FPGA FIR filter. By performing a real-time convolution of the feedback error signal with an inverse filter, we can suppress arbitrarily many poles and zeros below 100 kHz, each with a linewidth down to 10 Hz. We demonstrate the efficacy of this technique by canceling the ten largest mechanical resonances and anti-resonances of a high-finesse optical resonator, thereby enhancing the unity gain frequency by more than an order of magnitude. This approach is applicable to a broad array of stabilization problems including optical resonators, external cavity diode lasers, and scanning tunneling microscopes and points the way to applying modern optimal control techniques to intricate linear acoustical systems.

  17. Low-Complexity Adaptive Filtering Implementation for Acoustic Echo Cancellation

    OpenAIRE

    Schüldt, Christian; Lindström, Fredric; Claesson, Ingvar

    2006-01-01

    Acoustic echo cancellation is generally achieved with adaptive FIR filters. Due to the often large dimensionality of the adaptive filters, required to model rooms with standard reverberation time, the adaptation process can be computationally demanding. This paper presents a block based selective updating method which reduces the complexity with nearly a half in practical situations, while showing superior convergence speed performance as compared to conventional partial update complexity red...

  18. A wideband Noise-Canceling CMOS LNA exploiting a transformer

    NARCIS (Netherlands)

    Blaakmeer, S.C.; Klumperink, Eric A.M.; Leenaerts, Domine M.W.; Nauta, Bram

    2006-01-01

    A broadband LNA incorporating single-ended to differential conversion, has been successfully implemented using a noise-canceling technique and a single on-chip transformer. The LNA achieves a high voltage gain of 19dB, a wideband input match (2.5–4.0 GHz), and a Noise Figure of 4–5.4 dB, while

  19. A wideband Noise-Canceling CMOS LNA exploiting a transformer

    NARCIS (Netherlands)

    Blaakmeer, S.C.; Klumperink, Eric A.M.; Leenaerts, Domine M.W.; Nauta, Bram

    2006-01-01

    Abstract — A broadband LNA incorporating single-ended to differential conversion, has been successfully implemented using a noise-canceling technique and a single on-chip transformer. The LNA achieves a high voltage gain of 19dB, a wideband input match (2.5–4.0 GHz), and a Noise Figure of 4–5.4 dB,

  20. SIMULATION AND PERFORMANCE ANALYASIS OF ADAPTIVE FILTER IN NOISE CANCELLATION

    OpenAIRE

    RAJ KUMAR THENUA,; S.K. AGARWAL

    2010-01-01

    Noise problems in the environment have gained attention due to the tremendous growth of technology that has led to noisy engines, heavy machinery, high speed wind buffeting and other noise sources. The problem of controlling the noise level has become the focus of a tremendous amount of research over the years. In last few years various adaptive algorithms are developed for noise cancellation. In this paper we present an implementation of LMS (Least Mean Square), NLMS (Normalized Least Mean S...

  1. Laboratory Investigation of Noise-Canceling Headphones Utilizing ``Mr. Blockhead''

    Science.gov (United States)

    Koser, John

    2013-09-01

    While I was co-teaching an introductory course in musical acoustics a few years ago, our class investigated several pieces of equipment designed for audio purposes. One piece of such equipment was a pair of noise-canceling headphones. Our students were curious as to how these devices were in eliminating background noise and whether they indeed block low-frequency sounds as advertised.

  2. Measurement of the Specific Heat Using a Gravity Cancellation Approach

    Science.gov (United States)

    Zhong, Fang

    2003-01-01

    The specific heat at constant volume C(sob V) of a simple fluid diverges near its liquid-vapor critical point. However, gravity-induced density stratification due to the divergence of isothermal susceptibility hinders the direct comparison of the experimental data with the predictions of renormalization group theory. In the past, a microgravity environment has been considered essential to eliminate the density stratification. We propose to perform specific heat measurements of He-3 on the ground using a method to cancel the density stratification. A He-3 fluid layer will be heated from below, using the thermal expansion of the fluid to cancel the hydrostatic compression. A 6% density stratification at a reduced temperature of 10(exp -5) can be cancelled to better than 0.1% with a steady 1.7 micro K temperature difference across a 0.05 cm thick fluid layer. A conventional AC calorimetry technique will be used to determine the heat capacity. The minimized bulk density stratification with a relaxation time 6500 sec at a reduced temperature of 10(exp -5) will stay unchanged during 1 Hz AC heating. The smear of the specific heat divergence due to the temperature difference across the cell is about 0.1% at a reduced temperature of 10(exp -6). The combination of using High Resolution Thermometry with a 0.5 n K temperature resolution in the AC technique and the cancellation of the density stratification will enable C(sub V) to be measured down to a reduced temperature of 10(exp -6) with less than a 1% systematic error.

  3. Dynamic compression and recovery of cancellous bone for microstructural investigation

    OpenAIRE

    Pattofatto S.; Cloete T.J.; Prot M.

    2012-01-01

    Knowledge of soft porous materials, such as cancellous bone, under dynamic loading requires accurate descriptions of high-rate mechanical responses. A novel modification of the standard Split Hopkinson Pressure Bar (SHPB) technique, that makes dynamic specimen recovery possible, is presented. Two impedance matched tubes, operating in tandem, are concentrically aligned with the incidence bar and placed in contact with a collar at the striker end. The collar transfers half of the incidence stre...

  4. Limits to Clutter Cancellation in Multi-Aperture GMTI Data

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bickel, Douglas L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-03-01

    Multi-aperture or multi-subaperture antennas are fundamental to Ground Moving Target Indicator (GMTI) radar systems in order to detect slow-moving targets with Doppler characteristics similar to clutter. Herein we examine the performance of several subaperture architectures for their clutter cancelling performance. Significantly, more antenna phase centers isn’t always better, and in fact is sometimes worse, for detecting targets.

  5. An Ultrasonic Backscatter Instrument for Cancellous Bone Evaluation in Neonates

    Directory of Open Access Journals (Sweden)

    Chengcheng Liu

    2015-09-01

    Full Text Available Ultrasonic backscatter technique has shown promise as a noninvasive cancellous bone assessment tool. A novel ultrasonic backscatter bone diagnostic (UBBD instrument and an in vivo application for neonatal bone evaluation are introduced in this study. The UBBD provides several advantages, including noninvasiveness, non-ionizing radiation, portability, and simplicity. In this study, the backscatter signal could be measured within 5 s using the UBBD. Ultrasonic backscatter measurements were performed on 467 neonates (268 males and 199 females at the left calcaneus. The backscatter signal was measured at a central frequency of 3.5 MHz. The delay (T1 and duration (T2 of the backscatter signal of interest (SOI were varied, and the apparent integrated backscatter (AIB, frequency slope of apparent backscatter (FSAB, zero frequency intercept of apparent backscatter (FIAB, and spectral centroid shift (SCS were calculated. The results showed that the SOI selection had a direct influence on cancellous bone evaluation. The AIB and FIAB were positively correlated with the gestational age (|R| up to 0.45, P10 µs. Moderate positive correlations (|R| up to 0.45, P10 µs. The T2 mainly introduced fluctuations in the observed correlation coefficients. The moderate correlations observed with UBBD demonstrate the feasibility of using the backscatter signal to evaluate neonatal bone status. This study also proposes an explicit standard for in vivo SOI selection and neonatal cancellous bone assessment.

  6. Analysis of Simulation Methods for Far-end Crosstalk Cancellation

    Directory of Open Access Journals (Sweden)

    P. Lafata

    2011-04-01

    Full Text Available The information capacity of current digital subscriber lines is limited mainly by a crosstalk in metallic cables. The influence of near-end crosstalk (NEXT can be well cancelled by frequency duplex method, but the elimination of far-end crosstalk (FEXT is not so easy. Therefore FEXT is the dominant source of disturbance in current digital subscriber lines (xDSL. One of the most promising solutions for far-end crosstalk cancellation is Vectored Discrete Multi-tone modulation (VDMT. For the testing of VDMT modulation efficiency it will be necessary to implement advanced methods for modeling of far-end crosstalk to obtain required predictions of the crosstalk behavior in a cable. The actual simple FEXT model is not very accurate and does not provide realistic results. That is why the new method for modeling of far-end crosstalk was developed and is presented in this paper. This advanced model is based on the capacitive and inductive unbalances between pairs in a cable and it also respects the cable’s internal structure. The results of the model are subsequently used for the simulation of VDMT modulation and its impact on the FEXT cancellation. These simulations are based on the estimations of transmission speed of VDSL2 lines with VDMT modulation.

  7. Cancellation mechanism in the predictions of electric dipole moments

    Science.gov (United States)

    Bian, Ligong; Chen, Ning

    2017-06-01

    The interpretation of the baryon asymmetry of the Universe necessitates the C P violation beyond the Standard Model (SM). We present a general cancellation mechanism in the theoretical predictions of the electron electric dipole moments (EDM), quark chromo-EDMs, and Weinberg operators. A relative large C P violation in the Higgs sector is allowed by the current electron EDM constraint released by the ACME collaboration in 2013, and the recent 199Hg EDM experiment. The cancellation mechanism can be induced by the mass splitting of heavy Higgs bosons around ˜O (0.1 - 1 ) GeV , and the extent of the mass degeneracy determines the magnitude of the C P -violating phase. We explicate this point by investigating the C P -violating two-Higgs-doublet model and the minimal supersymmetric Standard Model. The cancellation mechanism is general when there are C P violation and mixing in the Higgs sector of new physics models. The C P -violating phases in this scenario can be excluded or detected by the projected 225Ra EDM experiments with precision reaching ˜10-28 e .cm , as well as the future colliders.

  8. Active current-noise cancellation for Scanning Tunneling Microscopy

    Science.gov (United States)

    Pabbi, Lavish; Shoop, Conner; Banerjee, Riju; Dusch, Bill; Hudson, E. W.

    The high sensitivity of the scanning tunneling microscope (STM) poses a barrier to its use in a noisy environment. Vibrational noise, whether structural or acoustic in source, manifests as relative motion between the probe tip and the sample, then appearing in the Z feedback that tries to cancel it. Here we describe an active noise cancellation process that nullifies this motion by adding a drive signal into the existing Z feedback loop. The drive is digitally calculated by actively monitoring vibrations measured by an accelerometer placed in-situ close to the STM head. By transferring the vibration cancellation effort to this drive signal, vibration-created noise in the Z-feedback (during topography) or current (during spectroscopy) is significantly reduced. This inexpensive and easy solution, requiring no major instrumental modifications, is ideal for those looking to place their STM in a noisier environment, for example in the presence of active refrigeration systems (e.g. pulse tube cryocoolers) or coupled to high-vibration instrumentation. This material is based upon work supported by the National Science Foundation under Grant No. 1229138.

  9. Effect of thermodisinfection on mechanic parameters of cancellous bone.

    Science.gov (United States)

    Fölsch, Christian; Kellotat, Andreas; Rickert, Markus; Ishaque, Bernd; Ahmed, Gafar; Pruss, Axel; Jahnke, Alexander

    2016-09-01

    Revision surgery of joint replacements is increasing and raises the demand for allograft bone since restoration of bone stock is crucial for longevity of implants. Proceedings of bone grafts influence the biological and mechanic properties differently. This study examines the effect of thermodisinfection on mechanic properties of cancellous bone. Bone cylinders from both femoral heads with length 45 mm were taken from twenty-three 6-8 months-old piglets, thermodisinfected at 82.5 °C according to bone bank guidelines and control remained native. The specimens were stored at -20 °C immediately and were put into 21 °C Ringer's solution for 3 h before testing. Shear and pressure modulus were tested since three point bending force was examined until destruction. Statistical analysis was done with non-parametric Wilcoxon, t test and SPSS since p mechanic properties of cancellous bone and the reduction of mechanic properties should not relevantly impair clinical use of thermodisinfected cancellous bone.

  10. Analysis of neuro-theatre utilisation and reasons for cancellation to improve efficiency and productivity.

    Science.gov (United States)

    Sharouf, Feras; Baig Mirza, Asfand; Moosajee, Vazira; Plummer, Sarah; Bhatti, Imran M; Zaben, Malik

    2017-04-01

    In neurosurgery, much emphasis has recently been placed on theatre cancellation and time utilization as a key hospital management performance indicator. We sought to evaluate our unit's theatre throughput efficiency and identify the causes of elective surgery cancellations. We retrospectively audited all scheduled elective neurosurgical procedures over a period of nine months. Mean theatre utilization time was 47.0%. The common causes of cancellations were lack of theatre time (32%), non-availability of beds in recovery room (18.6%), and insufficient preoperative patient preparation (5.5%). Inefficiencies were noted in turnover of patients and inaccurate prediction of operative time. Our theatre utilization time is consistent with available literature; however, cancellations of elective surgery waste valuable operative time and resources. The study concludes that a multi-dimensional approach must be taken to improve theatre utilization and reduce cancellation rates. A pre-assessment clinic has been introduced in order to reduce cancellation rates. Copyright the Association for Perioperative Practice.

  11. Performance Analysis of LMS Adaptive FIR Filter and RLS Adaptive FIR Filter for Noise Cancellation

    OpenAIRE

    Jyotsna Yadav; Mukesh Kumar; Rohini Saxena; Jaiswal, A K

    2013-01-01

    Interest in adaptive filters continues to grow as they begin to find practical real-time applications in areas such as channel equalization, echo cancellation, noise cancellation and many other adaptive signal processing applications. The key to successful adaptive signal processing understands the fundamental properties of adaptive algorithms such as LMS, RLS etc. Adaptive filter is used for the cancellation of the noise component which is overlap with undesired si...

  12. Empirical properties of inter-cancellation durations in the Chinese stock market

    Directory of Open Access Journals (Sweden)

    Gao-Feng eGu

    2014-03-01

    Full Text Available Order cancellation process plays a crucial role in the dynamics of price formation in order-driven stock markets and is important in the construction and validation of computational finance models. Based on the order flow data of 23 liquid stocks traded on the Shenzhen Stock Exchange in 2003, we investigate the empirical statistical properties of inter-cancellation durations in units of events defined as the waiting times between two consecutive cancellations. The inter-cancellation durations for both buy and sell orders of all the stocks favor a $q$-exponential distribution when the maximum likelihood estimation method is adopted; In contrast, both cancelled buy orders of 9 stocks and cancelled sell orders of 4 stocks prefer Weibull distribution when the nonlinear least-square estimation is used. Applying detrended fluctuation analysis (DFA, centered detrending moving average (CDMA and multifractal detrended fluctuation analysis (MF-DFA methods, we unveil that the inter-cancellation duration time series process long memory and multifractal nature for both buy and sell cancellations of all the stocks. Our findings show that order cancellation processes exhibit long-range correlated bursty behaviors and are thus not Poissonian.

  13. Active Electromagnetic Interference Cancelation for Automotive Switch-Mode Audio Power Amplifiers

    DEFF Research Database (Denmark)

    Knott, Arnold; Pfaffinger, Gerhard; Andersen, Michael A. E.

    2009-01-01

    Recent trends in the automotive audio industry have shown the importance of active noise cancelation (ANC) for major improvements in mobile entertainment environments. These approaches target the acoustical noise in the cabin and superimpose an inverse noise signal to cancel disturbances. Electro......Recent trends in the automotive audio industry have shown the importance of active noise cancelation (ANC) for major improvements in mobile entertainment environments. These approaches target the acoustical noise in the cabin and superimpose an inverse noise signal to cancel disturbances...

  14. ELM (Extreme Learning Machine Based Correlated Interference Canceller for Small Aperture Array Antenna

    Directory of Open Access Journals (Sweden)

    Junseok Lim

    2014-04-01

    Full Text Available The multipath effect creates a highly correlated interference. Subsequently, small aperture array antennas equipped in mobile devices must be able to effectively cancel this coherent interference. Spatial smoothing MMSE is a typical coherent interference cancellation algorithm; however, this method further reduces the small aperture size and reduces the number of coherent interferences to cancel out. This paper proposes a new method to reject coherent interferences without a reduction in the antenna aperture size. We show the superiority of the proposed algorithm through a comparison of cancellation performance with existing adaptive beamforming algorithms.

  15. A New Approach to Parallel Interference Cancellation for CDMA

    Science.gov (United States)

    Divsalar, Dariush; Simon, Martin

    1996-01-01

    This paper introduces an improved nonlinear parallel interference cancellation scheme that significantly reduces the degrading effect of user interference with implementation complexity linear in the number of users. The scheme operates on the fact that parallel processing simultaneously removes from each user a part of the interference produced by the remaining users accessing the channel the amount being proportional to their reliability. The parallel processing can be done in multiple stages. Simulation results are given for a multitude of different situations, in particular those cases for which the analysis is too complex.

  16. Thermal invisibility based on scattering cancellation and mantle cloaking

    KAUST Repository

    Farhat, Mohamed

    2015-04-30

    We theoretically and numerically analyze thermal invisibility based on the concept of scattering cancellation and mantle cloaking. We show that a small object can be made completely invisible to heat diffusion waves, by tailoring the heat conductivity of the spherical shell enclosing the object. This means that the thermal scattering from the object is suppressed, and the heat flow outside the object and the cloak made of these spherical shells behaves as if the object is not present. Thermal invisibility may open new vistas in hiding hot spots in infrared thermography, military furtivity, and electronics heating reduction.

  17. Osteoblast recruitment routes in human cancellous bone remodeling

    DEFF Research Database (Denmark)

    Kristensen, Helene B; Levin Andersen, Thomas; Marcussen, Niels

    2014-01-01

    It is commonly proposed that bone forming osteoblasts recruited during bone remodeling originate from bone marrow perivascular cells, bone remodeling compartment canopy cells, or bone lining cells. However, an assessment of osteoblast recruitment during adult human cancellous bone remodeling...... is lacking. We addressed this question by quantifying cell densities, cell proliferation, osteoblast differentiation markers, and capillaries in human iliac crest biopsy specimens. We found that recruitment occurs on both reversal and bone-forming surfaces, as shown by the cell density and osterix levels...

  18. Statistical process control for cancelled operations at the paediatric surgery department of a university hospital.

    Science.gov (United States)

    Abdel Wahab, Moataza M; Abou El-Enein, Nagwa Y

    2009-01-01

    Being a cause of delayed patient management and underutilization of resources, cancelled operations are considered a low quality service. Moreover, anticipation of surgery is stressful for both patients and families, particularly if the patient is a child; additional anxiety posed by last-minute cancellation is, therefore, of primary concern. The present study was done to estimate the rate and explore the determinant causes of cancellation of planned operations on the day of surgery at the paediatric surgery department of a university hospital in Alexandria. A cross sectional study was performed, interviewing some paediatric surgeons and anaesthesiologists practising at the hospital to collect in depth information about causes of cancelled operations, in addition to revising daily operation sheets for 181 operations to calculate cancellation rate and causes of cancelled operations. To Study patterns of variation in cancellation rate, a control chart (p-chart) was drawn. The overall cancellation rate was almost 25%. Analysis of the control chart showed an average cancellation rate of 25%, upper control limit of 74% and a Lower control limit of zero. Of the cancelled operations, 64.4% were of avoidable causes. Pareto chart showed that not being fit for anaesthesia either for electrolyte disturbances, low haemoglobin level or fever was the commonest reason for cancellation of operation, followed by patient having chest infection and patient or doctors not showing on the day of operation (those formed more than 85% of causes). Implementation of outpatient preoperative assessment and preparation for surgery, in addition to the improvement of communication between patient, doctors and nurses are highly recommended.

  19. Octopus-inspired drag cancelation by added mass pumping

    Science.gov (United States)

    Weymouth, Gabriel; Giorgio-Serchi, Francesco

    2016-11-01

    Recent work has shown that when an immersed body suddenly changes its size, such as a deflating octopus during rapid escape jetting, the body experiences large forces due to the variation of added-mass energy. We extend this line of research by investigating a spring-mass oscillator submerged in quiescent fluid subject to periodic changes in its volume. This system isolates the ability of the added-mass thrust to cancel the bluff body resistance (having no jet flow to confuse the analysis) and moves closer to studying how these effects would work in a sustained propulsion case by studying periodic shape-change instead of a "one-shot" escape maneuver. With a combination of analytical, numerical, and experimental results, we show that the recovery of added-mass kinetic energy can be used to completely cancel the drag of the fluid, driving the onset of sustained oscillations with amplitudes as large as four times the average body radius. Moreover, these results are fairly independent of the details of the shape-change kinematics as long as the Stokes number and shape-change number are large. In addition, the effective pumping frequency range based on parametric oscillator analysis is shown to predict large amplitude response region observed in the numerics and experiments.

  20. Cancellation of RF Coupler-Induced Emittance Due to Astigmatism

    Energy Technology Data Exchange (ETDEWEB)

    Dowell, David H.; /SLAC

    2016-12-11

    It is well-known that the electron beam quality required for applications such as FEL’s and ultra-fast electron diffraction can be degraded by the asymmetric fields introduced by the RF couplers of superconducting linacs. This effect is especially troublesome in the injector where the low energy beam from the gun is captured into the first high gradient accelerator section. Unfortunately modifying the established cavity design is expensive and time consuming, especially considering that only one or two sections are needed for an injector. Instead, it is important to analyze the coupler fields to understand their characteristics and help find less costly solutions for their cancellation and mitigation. This paper finds the RF coupler-induced emittance for short bunches is mostly due to the transverse spatial sloping or tilt of the field, rather than the field’s time-dependence. It is shown that the distorting effects of the coupler can be canceled with a static (DC) quadrupole lens rotated about the z-axis.

  1. Cryopreserved cancellous bone allograft in periodontal intraosseous defects.

    Science.gov (United States)

    Borghetti, A; Novakovitch, G; Louise, F; Simeone, D; Fourel, J

    1993-02-01

    The purpose of this study was to evaluate the potential of cryopreserved cancellous bone allograft (CCBA) in the treatment of intraosseous periodontal defects compared to surgical debridement alone (DEBR). Cancellous bone was procured from femur heads that had been extracted for hip prosthesis procedures and cryopreserved in liquid nitrogen (-196 degrees C) in a tissue bank. Ten patients without systemic disorders and advanced periodontal disease (at least 2 intraosseous defects) participated in this investigation. Measurements from the cemento-enamel junction were made after initial therapy for clinical attachment level; also gingival recession, probing pocket depth, plaque index, and gingival index and, at the time of surgery, alveolar crest height and osseous defect depth were measured. All measurements were repeated at 1 year-reentry. Sixteen defects were debrided and grafted (test sites) and 13 defects were debrided only (control sites). Soft tissue measurements showed no statistical differences between the 2 groups. Defect fill was significantly greater with CCBA (1.75 mm) than with DEBR (0.56 mm). Defect depth reduction was 2.06 mm for CCBA and 0.78 mm for DEBR. These values correspond to a percent-defect resolution of 60% for CCBA and 29% for DEBR. Hard tissue measurements showed significant differences between the 2 groups. CCBA seems to be effective in the short-term treatment of intraosseous periodontal defects.

  2. Dynamic Mechanical Testing Techniques for Cortical and Cancellous Bone

    Science.gov (United States)

    Cloete, Trevor

    2017-06-01

    Bone fracture typically occurs as an impact loading event (sporting accidents, vehicle collisions), the simulation of which requires in-depth understanding of dynamic bone behavior. Bone is a natural composite material with a complex multi length-scale hierarchical microstructure. At a macroscopic level, it is classified into hard/compact cortical bone and soft/spongy cancellous (trabecular) bone, though both are low-impedance materials relative to steels. Cortical bone is predominant in long bones, while in complex bone geometries (joints, flat bones) a cancellous bone core supports a thin cortical shell. Bone has primarily been studied at quasi-static strain rates (ɛ˙ intermediate strain rates (ISR) (1s-1 strain-rate dependent, non-linear, visco-elastic-brittle materials. Recent state-of-the-art experimental developments in dynamic bone testing are reviewed, with emphasis on pulse shaping, momentum trapping and ISR testing. These techniques allow for dynamic bone testing at small strains and near-constant strain rates with intact specimen recovery. The results are compared to those obtained with varying strain rate tests. Interrupted dynamic test results with microstructural analysis of the recovered specimens are presented and discussed. The paper concludes with a discussion of the experimental and modeling challenges that lie ahead in the field of dynamic bone behavior. The financial assistance of the National Research Foundation and the University of Cape Town towards this research is hereby acknowledged. Opinions expressed and conclusions arrived at are those of the author alone.

  3. Cancellous bone homograft storage with aluminium-polyethylene bags.

    Science.gov (United States)

    Meana, A; Martinez, R; Cañal, P; Arriaga, M J; Román, F San; Llames, S; Orós, C; Moreno, A; Fernandez, C

    2006-01-01

    In order to transport and cryopreserve human tissues, it is essential to have an easy-to-use recipient where tissues can be kept in sterile conditions. Here we show the results obtained by using Macopharma's tissue freezing bags, an aluminium-polyethylene multilayer bag, in our tissue bank of the Centro Comunitario de Sangre y Tejidos de Asturias. Five hundred and twenty-seven cancellous bone homografts were obtained from hospitals located 120 km around our Bank. The homografts were submitted to bacteriological controls and sent to our bank in these bags. They were stored at -70 degrees C and sent in dry ice to about 50 hospitals, where the tissue was bacteriologically controlled and grafted. Furthermore, the behaviour of these bags at -140 degrees C (vapour nitrogen) or -196 degrees C (liquid nitrogen) was tested. Our results indicate that Macopharma aluminium-polyethylene bags are suitable for the transporting and cryopreserving of cancellous bone homografts. These bags could also be used for keeping tissues in nitrogen containers.

  4. The generalized sidelobe canceller based on quaternion widely linear processing.

    Science.gov (United States)

    Tao, Jian-wu; Chang, Wen-xiu

    2014-01-01

    We investigate the problem of quaternion beamforming based on widely linear processing. First, a quaternion model of linear symmetric array with two-component electromagnetic (EM) vector sensors is presented. Based on array's quaternion model, we propose the general expression of a quaternion semiwidely linear (QSWL) beamformer. Unlike the complex widely linear beamformer, the QSWL beamformer is based on the simultaneous operation on the quaternion vector, which is composed of two jointly proper complex vectors, and its involution counterpart. Second, we propose a useful implementation of QSWL beamformer, that is, QSWL generalized sidelobe canceller (GSC), and derive the simple expressions of the weight vectors. The QSWL GSC consists of two-stage beamformers. By designing the weight vectors of two-stage beamformers, the interference is completely canceled in the output of QSWL GSC and the desired signal is not distorted. We derive the array's gain expression and analyze the performance of the QSWL GSC in the presence of one type of interference. The advantage of QSWL GSC is that the main beam can always point to the desired signal's direction and the robustness to DOA mismatch is improved. Finally, simulations are used to verify the performance of the proposed QSWL GSC.

  5. The Generalized Sidelobe Canceller Based on Quaternion Widely Linear Processing

    Directory of Open Access Journals (Sweden)

    Jian-wu Tao

    2014-01-01

    Full Text Available We investigate the problem of quaternion beamforming based on widely linear processing. First, a quaternion model of linear symmetric array with two-component electromagnetic (EM vector sensors is presented. Based on array’s quaternion model, we propose the general expression of a quaternion semiwidely linear (QSWL beamformer. Unlike the complex widely linear beamformer, the QSWL beamformer is based on the simultaneous operation on the quaternion vector, which is composed of two jointly proper complex vectors, and its involution counterpart. Second, we propose a useful implementation of QSWL beamformer, that is, QSWL generalized sidelobe canceller (GSC, and derive the simple expressions of the weight vectors. The QSWL GSC consists of two-stage beamformers. By designing the weight vectors of two-stage beamformers, the interference is completely canceled in the output of QSWL GSC and the desired signal is not distorted. We derive the array’s gain expression and analyze the performance of the QSWL GSC in the presence of one type of interference. The advantage of QSWL GSC is that the main beam can always point to the desired signal’s direction and the robustness to DOA mismatch is improved. Finally, simulations are used to verify the performance of the proposed QSWL GSC.

  6. Dynamic compression and recovery of cancellous bone for microstructural investigation

    Directory of Open Access Journals (Sweden)

    Pattofatto S.

    2012-08-01

    Full Text Available Knowledge of soft porous materials, such as cancellous bone, under dynamic loading requires accurate descriptions of high-rate mechanical responses. A novel modification of the standard Split Hopkinson Pressure Bar (SHPB technique, that makes dynamic specimen recovery possible, is presented. Two impedance matched tubes, operating in tandem, are concentrically aligned with the incidence bar and placed in contact with a collar at the striker end. The collar transfers half of the incidence stress wave and most (>90% of the reflected stress wave into the concentric tubes. In other words, the tubes act as sequential momentum traps and provide a single specimen loading event of predefined intensity and duration. This approach allows for routine testing without the need for initial “gap setting” , i.e. an accurate initial offset of the momentum trap with respect to the collar. Experimental results from a series of tests on cancellous bovine bone are presented. Furthermore, results from a microstructural investigation of the recovered specimens are presented and compared with quasi-statically loaded specimens.

  7. Dynamic compression and recovery of cancellous bone for microstructural investigation

    Science.gov (United States)

    Prot, M.; Cloete, T. J.; Pattofatto, S.

    2012-08-01

    Knowledge of soft porous materials, such as cancellous bone, under dynamic loading requires accurate descriptions of high-rate mechanical responses. A novel modification of the standard Split Hopkinson Pressure Bar (SHPB) technique, that makes dynamic specimen recovery possible, is presented. Two impedance matched tubes, operating in tandem, are concentrically aligned with the incidence bar and placed in contact with a collar at the striker end. The collar transfers half of the incidence stress wave and most (>90%) of the reflected stress wave into the concentric tubes. In other words, the tubes act as sequential momentum traps and provide a single specimen loading event of predefined intensity and duration. This approach allows for routine testing without the need for initial "gap setting" , i.e. an accurate initial offset of the momentum trap with respect to the collar. Experimental results from a series of tests on cancellous bovine bone are presented. Furthermore, results from a microstructural investigation of the recovered specimens are presented and compared with quasi-statically loaded specimens.

  8. Effects of room impulse responses to stereophonic acoustic echo cancellation

    Science.gov (United States)

    Kim, Jeonghee

    2000-09-01

    Teleconferencing provides people the ability to hold meetings in different locations without traveling. Currently, most teleconferencing systems use full duplex single channel for voice communication. These systems use an acoustic echo canceller to reduce echoes resulting from the coupling between the microphone and the speaker. To provide a more realistic presence and spatial realism that one-channel systems cannot offer, future teleconferencing systems are expected to have at least two channels (stereophonic sound) of full duplex voice communication. However stereophonic acoustic echo cancellation (AEC) is fundamentally different from monophonic AEC. In this work, we review some of adaptive filters used for the AEC systems and develop exponentially weighted step size for two-channel normalized least mean square (2C- NLMS) and generalized normalized least mean square (2C- GNLMS or APA: affine projection algorithm) adaptive algorithms based on the statistics of room impulse response. In one-channel AEC systems, there is only one acoustic echo path to identify. However, there are four acoustic echo paths to identify in two-channel AEC systems, so non-uniqueness problems exist. These problems are presented and some approaches done by researchers are shown with simulations. Finally, effects of room impulse responses, transmission room and receiving room impulse responses, and returning echoes into the transmission room to the performance of adaptive filters are simulated. A comparison of error performance with echoes and without echoes is presented.

  9. Application of adaptive noise cancellation to Coast Guard voice communications

    Science.gov (United States)

    Peterson, B. B.; Dykstra, K. U.; Sakahara, M. D.

    1985-03-01

    A variety of approaches to the digital filtering of voice signals corrupted by background engine noise are presented. These approaches include the standard Least Mean Square adaptive noise cancellation algorithm, an optimum fixed weight filter, a special type of notch filter and frequency domain adaptive noise cancellation. The filters have been implemented both off-line using FORTRAN programs on an LSI-11/2 microcomputer, and in real time using thee Texas Instruments TMS 320 microprocessor and in PDP-11 assembly language using an LSI-11/2. Frequency domain adaptive filtering was seen to be superior to the LMS time domain algorithm because its much greater computational efficiency allowed the analysis of much longer filters. A digital filter that exploits the engine noise by having a notch at each harmonic was seen to be more effective than any of the adaptive filters. The digital filter equations are derived, starting with a particular periodic reference input. This adaptive filter is shown to be, in reality, an infinite impulse response, time invariant filter.

  10. Subband Affine Projection Algorithm for Acoustic Echo Cancellation System

    Directory of Open Access Journals (Sweden)

    Choi Hun

    2007-01-01

    Full Text Available We present a new subband affine projection (SAP algorithm for the adaptive acoustic echo cancellation with long echo path delay. Generally, the acoustic echo canceller suffers from the long echo path and large computational complexity. To solve this problem, the proposed algorithm combines merits of the affine projection (AP algorithm and the subband filtering. Convergence speed of the proposed algorithm is improved by the signal-decorrelating property of the orthogonal subband filtering and the weight updating with the prewhitened input signal of the AP algorithm. Moreover, in the proposed algorithms, as applying the polyphase decomposition, the noble identity, and the critical decimation to subband the adaptive filter, the sufficiently decomposed SAP updates the weights of adaptive subfilters without a matrix inversion. Therefore, computational complexity of the proposed method is considerably reduced. In the SAP, the derived weight updating formula for the subband adaptive filter has a simple form as ever compared with the normalized least-mean-square (NLMS algorithm. The efficiency of the proposed algorithm for the colored signal and speech signal was evaluated experimentally.

  11. Motivating inhibition - reward prospect speeds up response cancellation.

    Science.gov (United States)

    Boehler, Carsten N; Hopf, Jens-Max; Stoppel, Christian M; Krebs, Ruth M

    2012-12-01

    Reward prospect has been demonstrated to facilitate various cognitive and behavioral operations, particularly by enhancing the speed and vigor of processes linked to approaching reward. Studies in this domain typically employed task regimes in which participants' overt responses are facilitated by prospective rewards. In contrast, we demonstrate here that even the cancellation of a motor response can be accelerated by reward prospect, thus signifying reward-related benefits on restraint rather than approach behavior. Importantly, this facilitation occurred independent of strategy-related adjustments of response speed, which are known to systematically distort the estimation of response-cancellation speed. The fact that motivational factors can indeed facilitate response inhibition is not only relevant for understanding how motivation and response inhibition interact in healthy participants but also for work on various patient groups that display response-inhibition deficits, suggesting that core differences in the ability to inhibit motor responses have to be differentiated from motivational factors. Copyright © 2012 Elsevier B.V. All rights reserved.

  12. Reasons for cancellation of operation on the day of intended surgery in a multidisciplinary 500 bedded hospital

    Directory of Open Access Journals (Sweden)

    Rajender Kumar

    2012-01-01

    Full Text Available Background: Cancellation of operations in hospitals is a significant problem with far reaching consequences. This study was planned to evaluate reasons for cancellation of elective surgical operation on the day of surgery in a 500 bedded Government hospital. Materials and Methods: The medical records of all the patients, from December 2009 to November 2010, who had their operations cancelled on the day of surgery in all surgical units of the hospital, were audited prospectively. The number of operation cancelled and reasons for cancellation were documented. Results: 7272 patients were scheduled for elective surgical procedures during study period; 1286 (17.6 % of these were cancelled on the day of surgery. The highest number of cancellation occurred in the discipline of general surgery (7.1% and the least (0.35% occurred in Ear-Nose-Throat surgery. The most common cause of cancellation was the lack of availability of theater time 809 (63% and patients not turning up 244 (19% patients. 149 cancellations (11.6% were because of medical reasons; 16 (1.2% were cancelled by the surgeon due to a change in the surgical plan; 28 (2.1% were cancelled as patients were not ready for surgery; and 40 (3.1% were cancelled due to equipment failure.]. Conclusion: Most causes of cancellations of operations are preventable.

  13. 78 FR 53702 - Computation of, and Rules Relating to, Medical Loss Ratio; Hearing Cancellation

    Science.gov (United States)

    2013-08-30

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE TREASURY Internal Revenue Service 26 CFR Part 1 RIN 1545-BL05 Computation of, and Rules Relating to, Medical Loss Ratio; Hearing Cancellation AGENCY: Internal Revenue Service (IRS), Treasury. ACTION: Cancellation of a...

  14. 76 FR 44906 - Foremost 4809-ES Insect-O-Fog; Amended Cancellation Order

    Science.gov (United States)

    2011-07-27

    ... 4809-ES Insect-O-Fog; Amended Cancellation Order AGENCY: Environmental Protection Agency (EPA). ACTION...), of an amended cancellation order for the pesticide product Foremost 4809-ES Insect-O-Fog, a pesticide product containing Piperonyl Butoxide and Pyrethrins. The registrant of Foremost 4809-ES Insect-O-Fog...

  15. 7 CFR 301.45-6 - Compliance agreement and cancellation thereof.

    Science.gov (United States)

    2010-01-01

    ... compliance agreement may be canceled by the inspector who is supervising its enforcement, orally or in writing, whenever the inspector finds that such person has failed to comply with the conditions of the agreement. If the cancellation is oral, the decision and the reasons therefore shall be confirmed in writing...

  16. Continuous weakly cancellative triangular subnorms: I. Their web-geometric properties

    Czech Academy of Sciences Publication Activity Database

    Petrík, Milan; Sarkoci, Peter

    2018-01-01

    Roč. 332, 1 February (2018), s. 93-110 ISSN 0165-0114 R&D Projects: GA ČR GJ15-07724Y Institutional support: RVO:67985807 Keywords : associativity * conditionally cancellative * continuous triangular subnorm * contour * level set * Reidemeister closure condition * weakly cancellative * web geometry Subject RIV: BA - General Mathematics Impact factor: 2.718, year: 2016

  17. Age-related variations in the microstructure of human tibial cancellous bone

    DEFF Research Database (Denmark)

    Ding, Ming; Odgaard, A; Linde, F

    2002-01-01

    -related changes in the three-dimensional (3D) microstructure of human tibial cancellous bone. One hundred and sixty cylindrical cancellous bone specimens were produced from 40 normal proximal tibiae from 40 donors, aged 16-85 years. These specimens were micro-computed tomography (micro-CT) scanned...

  18. 42 CFR 57.311 - Cancellation of nursing student loans for disability or death.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Cancellation of nursing student loans for disability or death. 57.311 Section 57.311 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND..., SCHOLARSHIPS AND STUDENT LOANS Nursing Student Loans § 57.311 Cancellation of nursing student loans for...

  19. 76 FR 51031 - Registration; Cancellation Order for Rodenticide Products That Have Expired

    Science.gov (United States)

    2011-08-17

    ... AGENCY Registration; Cancellation Order for Rodenticide Products That Have Expired AGENCY: Environmental... attempted to describe all the specific entities that may be affected by this action. If you have any... cancellation proceedings against similar rodenticide registrations that have not expired. See http://yosemite...

  20. 78 FR 64254 - Advisory Committee for Education and Human Resources; Cancellation of Meeting

    Science.gov (United States)

    2013-10-28

    ... From the Federal Register Online via the Government Publishing Office NATIONAL SCIENCE FOUNDATION Advisory Committee for Education and Human Resources; Cancellation of Meeting SUMMARY: As a result of the... cancel the November 6-7, 2013 Advisory Committee for Education and Human Resources meeting. The public...

  1. Influences on the Timing and Frequency of Cancellations and Truncations of Major Defense Acquisition Programs

    Science.gov (United States)

    2017-03-01

    scientific and technical expertise, and conduct related research on other national challenges. About this Publication This work was conducted by the... climate had statistically discernible associations with cancellations of Major Defense Acquisition Programs (MDAPs). Data on reductions of the...Policy and Process and Funding Climate on Cancellations of Major Defense Acquisition Programs,” IDA Paper P-5218 (Alexandria, VA: Institute for

  2. On Acoustic Feedback Cancellation Using Probe Noise in Multiple-Microphone and Single-Loudspeaker Systems

    DEFF Research Database (Denmark)

    Guo, Meng; Elmedyb, Thomas Bo; Jensen, Søren Holdt

    2012-01-01

    feedback cancellation is carried out using a probe noise signal. The derived results show how different system parameters and signal properties affect the cancellation performance, and the results explain theoretically the decreased convergence rate. Understanding this is important for making further...

  3. 30 CFR 250.184 - What is the amount of compensation for lease cancellation?

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What is the amount of compensation for lease cancellation? 250.184 Section 250.184 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR... Requirements, Lease Term Extensions, and Lease Cancellations § 250.184 What is the amount of compensation for...

  4. Evaluation of State-of-the-Art Acoustic Feedback Cancellation Systems for Hearing Aids

    DEFF Research Database (Denmark)

    Guo, Meng; Jensen, Søren Holdt; Jensen, Jesper

    2013-01-01

    This research evaluates four state-of-the-art acoustic feedback cancellation systems in hearing aids in terms of the cancellation performance, sound quality degradation, and computational complexity. The authors compared a traditional full-band system to a system with a prediction error method...

  5. Numerical investigation of reflection properties of fast and slow longitudinal waves in cancellous bone.

    Science.gov (United States)

    Hosokawa, Atsushi

    2013-05-01

    The basic reflection properties of fast and slow waves propagating in cancellous bone were numerically investigated using finite-difference time-domain (FDTD) simulations with 18 microcomputed tomographic (µCT) models of bovine cancellous bone. The simulated results showed that both reflection coefficients of the fast and slow waves linearly increased with porosity.

  6. 37 CFR 2.113 - Notification to parties of cancellation proceeding.

    Science.gov (United States)

    2010-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Notification to parties of cancellation proceeding. 2.113 Section 2.113 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT OF COMMERCE RULES OF PRACTICE IN TRADEMARK CASES Cancellation § 2.113...

  7. 37 CFR 2.115 - Amendment of pleadings in a cancellation proceeding.

    Science.gov (United States)

    2010-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Amendment of pleadings in a cancellation proceeding. 2.115 Section 2.115 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT OF COMMERCE RULES OF PRACTICE IN TRADEMARK CASES Cancellation § 2.115 Amendment...

  8. 77 FR 75631 - Halofenozide; Cancellation Order for All Pesticide Registrations and Termination of All Uses

    Science.gov (United States)

    2012-12-21

    ... Notice of Receipt of Requests from the registrants listed in Table 2 of Unit II. to voluntarily cancel... sequence by registration number in Table 1 of this unit. Table 1--Halofenozide Product Cancellations EPA.... 062719-0476 Mach 2 Manufacturing Use Concentrate. 062719-0489 Mach 2 Plus Fertilizer (1.0% A.I.). 062719...

  9. 78 FR 24224 - National Institute of Allergy and Infectious Diseases; Cancellation of Meeting

    Science.gov (United States)

    2013-04-24

    ... From the Federal Register Online via the Government Publishing Office ] DEPARTMENT OF HEALTH AND HUMAN SERVICES National Institutes of Health National Institute of Allergy and Infectious Diseases; Cancellation of Meeting Notice is hereby given of the cancellation of the AIDS Research Advisory Committee...

  10. Restraint and Cancellation: Multiple Inhibition Deficits in Attention Deficit Hyperactivity Disorder

    Science.gov (United States)

    Schachar, Russell; Logan, Gordon D.; Robaey, Philippe; Chen, Shirley; Ickowicz, Abel; Barr, Cathy

    2007-01-01

    We used variations of the stop signal task to study two components of motor response inhibition--the ability to withhold a strong response tendency (restraint) and the ability to cancel an ongoing action (cancellation)--in children with a diagnosis of attention deficit hyperactivity disorder (ADHD) and in non-ADHD controls of similar age (ages…

  11. Changed morphology and mechanical properties of cancellous bone in the mandibular condyles of edentate people

    DEFF Research Database (Denmark)

    Ding, Ming

    2004-01-01

    Since edentate subjects have a reduced masticatory function, it can be expected that the morphology of the cancellous bone of their mandibular condyles has changed according to the altered mechanical environment. In the present study, the morphology of cylindrical cancellous bone specimens...

  12. 77 FR 53197 - Cancellation Order for Certain Pesticide Registrations: MGK 264, Pyrethrins, Pyriproxyfen, and...

    Science.gov (United States)

    2012-08-31

    ... AGENCY Cancellation Order for Certain Pesticide Registrations: MGK 264, Pyrethrins, Pyriproxyfen, and.../ Pyriproxyfen/Permethrin product EPA Reg. No. 010807-00448. This document corrects typographical errors in the... of the Amrep, Inc., MGK 264/Pyrethrins/ Pyriproxyfen/Permethrin product affected by the cancellation...

  13. Cancellation of Glauber gluon exchange in the double Drell-Yan process

    NARCIS (Netherlands)

    Diehl, M.; Gaunt, J.R.; Ostermeier, D.; Ploessl, P.; Schaefer, A.

    2016-01-01

    An essential part of any factorisation proof is the demonstration that the exchange of Glauber gluons cancels for the considered observable. We show this cancellation at all orders for double Drell-Yan production (the double parton scattering process in which a pair of electroweak gauge bosons is

  14. Cancellation of Glauber gluon exchange in the double Drell-Yan process

    NARCIS (Netherlands)

    Diehl, M.; Gaunt, J.R.; Ostermeier, D.; Ploessl, P.; Schaefer, A.

    2016-01-01

    For any factorisation proof, a crucial step is a demonstration of the cancellation of so-called Glauber gluons. We summarise a recent paper in which we demonstrated this cancellation for double Drell–Yan production (the double parton scattering process in which a pair of electroweak gauge bosons is

  15. Day of Surgery Admission in Total Joint Arthroplasty: Why Are Surgeries Cancelled? An Analysis of 3195 Planned Procedures and 114 Cancellations

    Directory of Open Access Journals (Sweden)

    David M. Dalton

    2016-01-01

    Full Text Available Background. Day of surgery admission (DOSA is becoming standard practice as a means of reducing cost in total joint arthroplasty. Aims. The aim of our study was to audit the use of DOSA in a specialty hospital and identify reasons for cancellation. Methods. A retrospective study of patients presenting for hip or knee arthroplasty between 2008 and 2013 was performed. All patients were assessed at the preoperative assessment clinic (PAC. Results. Of 3195 patients deemed fit for surgery, 114 patients (3.5% had their surgery cancelled. Ninety-two cancellations (80% were due to the patient being deemed medically unsuitable for surgery by the anaesthetist. Cardiac disease was the most common reason for cancellation (n=27, followed by pulmonary disease (n=22. 77 patients (67.5% had their operation rescheduled and successfully performed in our institution at a later date. Conclusion. DOSA is associated with a low rate of cancellations on the day of surgery. Patients with cardiorespiratory comorbidities are at greatest risk of cancellation.

  16. 77 FR 45648 - Notice of Cancellation of Customs Broker Licenses Due to Death of the License Holder

    Science.gov (United States)

    2012-08-01

    ... Cancellation of Customs Broker Licenses Due to Death of the License Holder AGENCY: U.S. Customs and Border... individual Customs broker licenses and any and all permits have been cancelled due to the death of the broker...

  17. Max-Min Fairness in WMNs with Interference Cancelation Using Overheard Transmissions

    Directory of Open Access Journals (Sweden)

    Mateusz Żotkiewicz

    2014-01-01

    Full Text Available We show an impact of using interference cancelation mechanisms for signals that have been overheard in the past on performance of fair wireless mesh networks. In our research we show that even in those very restricted conditions and max-min cost function, the idea of interference cancelation can significantly increase the capacity of such networks. In order to approximate possible advantages of using interference cancelation in the considered conditions, we propose a novel MIP model that allows for calculating perfect scheduling and maximal throughput in a network. We compare the results with cases when the interference cancelation mechanisms are disabled. Our results show that using interference cancelation mechanisms for signals that have been overheard in the past increases a network throughput by 40% on average in approximately 20% of test cases.

  18. A computer simulation of an adaptive noise canceler with a single input

    Science.gov (United States)

    Albert, Stuart D.

    1991-06-01

    A description of an adaptive noise canceler using Widrows' LMS algorithm is presented. A computer simulation of canceler performance (adaptive convergence time and frequency transfer function) was written for use as a design tool. The simulations, assumptions, and input parameters are described in detail. The simulation is used in a design example to predict the performance of an adaptive noise canceler in the simultaneous presence of both strong and weak narrow-band signals (a cosited frequency hopping radio scenario). On the basis of the simulation results, it is concluded that the simulation is suitable for use as an adaptive noise canceler design tool; i.e., it can be used to evaluate the effect of design parameter changes on canceler performance.

  19. A Dual Decomposition Approach to Partial Crosstalk Cancelation in a Multiuser DMT-xDSL Environment

    Directory of Open Access Journals (Sweden)

    Verlinden Jan

    2007-01-01

    Full Text Available In modern DSL systems, far-end crosstalk is a major source of performance degradation. Crosstalk cancelation schemes have been proposed to mitigate the effect of crosstalk. However, the complexity of crosstalk cancelation grows with the square of the number of lines in the binder. Fortunately, most of the crosstalk originates from a limited number of lines and, for DMT-based xDSL systems, on a limited number of tones. As a result, a fraction of the complexity of full crosstalk cancelation suffices to cancel most of the crosstalk. The challenge is then to determine which crosstalk to cancel on which tones, given a complexity constraint. This paper presents an algorithm based on a dual decomposition to optimally solve this problem. The proposed algorithm naturally incorporates rate constraints and the complexity of the algorithm compares favorably to a known resource allocation algorithm, where a multiuser extension is made to incorporate the rate constraints.

  20. Effect of six sigma program on the number of surgeries cancellation.

    Science.gov (United States)

    Gheysari, Esmat; Yousefi, Hojatollah; Soleymani, Hossain; Mojdeh, Soheila

    2016-01-01

    Today, the rate of surgeries is increasing, but surgeries are canceled due to various reasons. Unexpected cancellation of surgeries not only results in disorder in the operating room schedule, but also causes stress for patients and their family and increases costs. We determined the number and causes of surgery cancellations and areas for improvement. This outcome evaluation of Six Sigma program was conducted on 850 cases after the implementation of the program and compared to that of 850 cases which received routine care before the program. Cases were selected through easy sampling during the study. Before the implementation, the number of cancellations was recorded daily and their reasons were investigated. Then, Six Sigma program was implemented in accordance with the reasons for each category and necessary steps were taken to prevent the cancellation of surgeries. Data were collected for 3 months using a three-section data collection form. For data analysis, distribution and relative frequency and chi-square test were used. The three categories of patient, physician, and hospital system were identified as the main causes. The highest rate of cancellation was related to ENT surgeries (74.19%). No cancellations were made in orology surgeries. The implementation of the Six Sigma program caused a significant difference in surgery cancellation (P = 0.003); 31 (3.6%) cases of cancellation were reduced to 12 (1.4%) cases. The results showed that Six Sigma program is a pre-surgery care quality improvement program. Patient education and the implementation of the 6 sigma program can be effective in reducing the rate of cancellation of operations.

  1. 78 FR 48456 - Notice of Cancellation of Customs Broker Licenses Due to Death of the License Holder

    Science.gov (United States)

    2013-08-08

    ... SECURITY U.S. Customs and Border Protection Notice of Cancellation of Customs Broker Licenses Due to Death.... ACTION: Customs broker license cancellation due to death of the broker. SUMMARY: Notice is hereby given that the customs broker licenses of certain brokers have been cancelled without prejudice due to the...

  2. Efficient Multichannel NLMS Implementation for Acoustic Echo Cancellation

    Directory of Open Access Journals (Sweden)

    Schüldt Christian

    2007-01-01

    Full Text Available An acoustic echo cancellation structure with a single loudspeaker and multiple microphones is, from a system identification perspective, generally modelled as a single-input multiple-output system. Such a system thus implies specific echo-path models (adaptive filter for every loudspeaker to microphone path. Due to the often large dimensionality of the filters, which is required to model rooms with standard reverberation time, the adaptation process can be computationally demanding. This paper presents a selective updating normalized least mean square (NLMS-based method which reduces complexity to nearly half in practical situations, while showing superior convergence speed performance as compared to conventional complexity reduction schemes. Moreover, the method concentrates the filter adaptation to the filter which is most misadjusted, which is a typically desired feature.

  3. Efficient Multichannel NLMS Implementation for Acoustic Echo Cancellation

    Directory of Open Access Journals (Sweden)

    Fredric Lindstrom

    2007-02-01

    Full Text Available An acoustic echo cancellation structure with a single loudspeaker and multiple microphones is, from a system identification perspective, generally modelled as a single-input multiple-output system. Such a system thus implies specific echo-path models (adaptive filter for every loudspeaker to microphone path. Due to the often large dimensionality of the filters, which is required to model rooms with standard reverberation time, the adaptation process can be computationally demanding. This paper presents a selective updating normalized least mean square (NLMS-based method which reduces complexity to nearly half in practical situations, while showing superior convergence speed performance as compared to conventional complexity reduction schemes. Moreover, the method concentrates the filter adaptation to the filter which is most misadjusted, which is a typically desired feature.

  4. Common-mode noise cancellation circuit for wearable ECG.

    Science.gov (United States)

    Noro, Mutsumi; Anzai, Daisuke; Wang, Jianqing

    2017-04-01

    Wearable electrocardiogram (ECG) is attracting much attention for monitoring heart diseases in healthcare and medical applications. However, an imbalance usually exists between the contact resistances of sensing electrodes, so that a common mode noise caused by external electromagnetic field can be converted into the ECG detection circuit as a differential mode interference voltage. In this study, after explaining the mechanism of how the common mode noise is converted to a differential mode interference voltage, the authors propose a circuit with cadmium sulphide photo-resistors for cancelling the imbalance between the contact resistances and confirm its validity by simulation experiment. As a result, the authors found that the interference voltage generated at the wearable ECG can be effectively reduced to a sufficient small level.

  5. Spatial Intercell Interference Cancellation with CSI Training and Feedback

    CERN Document Server

    Zhang, Jun; Letaief, Khaled B

    2011-01-01

    We investigate intercell interference cancellation (ICIC) with a practical downlink training and uplink channel state information (CSI) feedback model. The average downlink throughput for such a 2-cell network is derived. The user location has a strong effect on the signal-to-interference ratio (SIR) and the channel estimation error. This motivates adaptively switching between traditional (single-cell) beamforming and ICIC at low signal-to-noise ratio (SNR) where ICIC is preferred only with low SIR and accurate channel estimation, and the use of ICIC with optimized training and feedback at high SNR. For a given channel coherence time and fixed training and feedback overheads, we develop optimal data vs. pilot power allocation for CSI training as well as optimal feedback resource allocation to feed back CSI of different channels. Both analog and finite-rate digital feedback are considered. With analog feedback, the training power optimization provides a more significant performance gain than feedback optimizat...

  6. An improved probe noise approach for acoustic feedback cancellation

    DEFF Research Database (Denmark)

    Guo, Meng; Jensen, Søren Holdt; Jensen, Jesper

    2012-01-01

    The perhaps most challenging problem in acoustic feedback cancellation using adaptive filters is the bias problem. It is well-known that a probe noise approach can effectively prevent this problem. However, when the probe noise must be inaudible and the steady-state error of the adaptive filter...... must be unchanged, this approach causes a significantly decreased convergence rate of the adaptive filter, and might thereby be less useful in practical applications. In this work, we propose a new probe noise approach which significantly increases the convergence rate while maintaining the steady......-state error of the adaptive algorithm in a multiple-microphone and single-loudspeaker audio system. This is obtained through a specifically designed probe noise signal and a corresponding probe noise enhancement strategy. We show the effects of the proposed probe noise approach by deriving analytical...

  7. A pseudo-cascade FXLMS approach to active vibration cancellation

    Science.gov (United States)

    Browning, Douglas R.; Morgan, Dennis R.

    An extension of the filtered-x LMS notch filter called the pseudocascade filtered-x LMS (PCFXLMS) algorithm is studied experimentally as an active vibration controller. A disturbance source with a controllable bandwidth is employed on a mechanical test structure with two sensors and two actuators. Analytical predictions for the PCFXLMS algorithm are compared to actual results of using the controller, and the nonstationary nature of the plant is shown to account for the discrepancies between analytical prediction and experiment in the region of control which coincides with the first structural resonance. The three-stage PCFXLMS controller can provide a cancellation bandwidth that increases by a factor of five the bandwidth yielded by a single stage adaptive notch filter.

  8. Alien Crosstalk Cancellation for Multipair Digital Subscriber Line Systems

    Directory of Open Access Journals (Sweden)

    Ginis George

    2006-01-01

    Full Text Available An overview of alien crosstalk cancellation for DSL systems with multiple pairs is here presented. It is shown that when a common crosstalk source affects the receivers of multiple pairs, the noise exhibits a certain correlation among the pairs. In a DMT system, the frequency-domain noise samples are most strongly correlated between pairs when they correspond to the same tone. Thus, noise decorrelation algorithms applied independently for each tone can provide significant performance enhancements. Three possible methods are described for noise decorrelation, one is suitable for two-sided coordination and two are suited for receiver coordination among the pairs. It is theoretically proven that the data-rate performance of these three methods is identical from the perspective of the sum rate over all pairs. Simulation results corresponding to an ADSL2+ two-pair system with a T1 disturber are presented to illustrate the noise correlation property and to indicate the potential performance benefits.

  9. Quantum Probability Cancellation Due to a Single-Photon State

    Science.gov (United States)

    Ou, Z. Y.

    1996-01-01

    When an N-photon state enters a lossless symmetric beamsplitter from one input port, the photon distribution for the two output ports has the form of Bernouli Binormial, with highest probability at equal partition (N/2 at one outport and N/2 at the other). However, injection of a single photon state at the other input port can dramatically change the photon distribution at the outputs, resulting in zero probability at equal partition. Such a strong deviation from classical particle theory stems from quantum probability amplitude cancellation. The effect persists even if the N-photon state is replaced by an arbitrary state of light. A special case is the coherent state which corresponds to homodyne detection of a single photon state and can lead to the measurement of the wave function of a single photon state.

  10. Interference Cancellation for Hollow-Core Fiber Reference Cells

    DEFF Research Database (Denmark)

    Seppä, Jeremias; Merimaa, Mikko; Merimaa, Mikko

    2015-01-01

    Doppler-free saturated absorption spectroscopy of gases in hollow-core fiber (HCF)-based cells can be used for realizing new compact, robust, and portable frequency standards. In this paper, methods for cancelling interferences resulting from the optical connections between standard fiber and HCF...... and other factors such as varying coupling to HCF modes are investigated. Laser power modulation with simultaneous detection of ac and dc signal is used to separate saturated absorption from interferences. In addition, a technique of two piezoelectric stack actuators stretching the fiber at different...... locations is described. The presented experimental results demonstrate that 99% interference attenuation is readily attainable with the techniques. Frequency comb-referenced measurement of saturated acetylene absorption features near 1.54 μm, with fiber length and power modulation, is presented...

  11. Platonic scattering cancellation for bending waves in a thin plate

    KAUST Repository

    Farhat, Mohamed

    2014-04-10

    We propose an ultra-thin elastic cloak to control the scattering of bending waves in isotropic heterogeneous thin plates. The cloak design makes use of the scattering cancellation technique applied, for the first time, to the biharmonic operator describing the propagation of bending waves in thin plates. We first analyze scattering from hard and soft cylindrical objects in the quasistatic limit, then we prove that the scattering of bending waves from an object in the near and far-field regions can be suppressed significantly by covering it with a suitably designed coating. Beyond camouflaging, these findings may have potential applications in protection of buildings from earthquakes and isolating structures from vibrations in the motor vehicle industry.

  12. CANCELLATION OF ELECTIVE OPERATIONS ON THE DAY OF SURGERY : THREE YEARS STUDY

    Directory of Open Access Journals (Sweden)

    Asmita

    2015-10-01

    Full Text Available OBJECTIVE: There are several studies suggesting decreased operating room efficiency caused by cancellations of the surgical procedures. It also affects patient satisfaction. This study was to analyse the reasons for cancellation of elective operations so that in future necessary actions can b e taken to minimize number of unnecessary cancellations. METHODS: This was a retrospective study conducted in teaching hospital for 3 years from April 1, 2012 to March 31, 2015. The data was collected from postponement register and medical record departmen t. The reasons for cancellations were classified as (1 structural factors (e.g., no hospital bed; (2 patient factors (e.g., patient unwell; and (3 process factors (e.g., scheduling error. RESULTS: During the study period, 11,208 patients were posted for elective procedures. 9.8 % patients were cancelled on the day of surgery. The frequency of cancellations was more in process related issues (47.9%. Cancellat ions due to structural factors and patient factors were 26.4% and 25.7% respectively. CONCLUSION: Although cancellations were only 9.8% of total elective operations, this can be reduced by anticipating and taking necessary steps that have been suggested. More thorough and detailed documentation is needed to achieve this

  13. Interference Cancellation for Coexisting Wireless Data and Power Transmission in the Same Frequency

    Science.gov (United States)

    Yamazaki, Keita; Sugiyama, Yusuke; Kawahara, Yoshihiro; Saruwatari, Shunsuke; Watanabe, Takashi

    2014-11-01

    Combining wireless transmission of data and power signals enables wireless sensor networks to drive perpetually without changing batteries. To achieve the simultaneous data and power transmission, the present paper proposes power signal interference cancellation for wireless data and power transmission at the same time in the same frequency. We evaluate the performance of the proposed power signal interference cancellation using Universal Software Radio Peripheral N200 (USRP N200) software defined radio. Evaluations show that the proposed interference cancellation is feasible to receive data while transmitting power.

  14. Cancellation of Glauber gluon exchange in the double Drell-Yan process

    Energy Technology Data Exchange (ETDEWEB)

    Diehl, Markus; Gaunt, Jonathan R. [DESY Hamburg (Germany); Ostermeier, Daniel; Ploessl, Peter; Schaefer, Andreas [Regensburg Univ. (Germany). Inst. fuer Theoretische Physik

    2015-10-15

    An essential part of any factorisation proof is the demonstration that the exchange of Glauber gluons cancels for the considered observable. We show this cancellation at all orders for double Drell-Yan production (the double parton scattering process in which a pair of electroweak gauge bosons is produced) both for the integrated cross section and for the cross section differential in the transverse boson momenta. In the process of constructing this proof, we also revisit and clarify some issues regarding the Glauber cancellation argument and its relation to the rest of the factorisation proof for the single Drell-Yan process.

  15. Cancellation of Glauber gluon exchange in the double Drell-Yan process

    Energy Technology Data Exchange (ETDEWEB)

    Diehl, Markus; Gaunt, Jonathan R. [Deutsches Elektronen-Synchroton DESY,22603 Hamburg (Germany); Ostermeier, Daniel; Plößl, Peter; Schäfer, Andreas [Institut für Theoretische Physik, Universität Regensburg,93040 Regensburg (Germany)

    2016-01-13

    An essential part of any factorisation proof is the demonstration that the exchange of Glauber gluons cancels for the considered observable. We show this cancellation at all orders for double Drell-Yan production (the double parton scattering process in which a pair of electroweak gauge bosons is produced) both for the integrated cross section and for the cross section differential in the transverse boson momenta. In the process of constructing this proof, we also revisit and clarify some issues regarding the Glauber cancellation argument and its relation to the rest of the factorisation proof for the single Drell-Yan process.

  16. 5 CFR 894.602 - May I cancel my enrollment at any time?

    Science.gov (United States)

    2010-01-01

    ... SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Termination or... percent or more employer-paid premiums. You may also cancel upon your deployment or your spouse's...

  17. 76 FR 55890 - Cancellation of Supplemental Environmental Impact Statement for Ancillary Facilities for the...

    Science.gov (United States)

    2011-09-09

    ... cancellation of the SEIS, contact Donald Silawsky, Acting Director, Office of Reserve Lands Management (FE-47), U.S. Department of Energy, 1000 Independence Ave., SW., Washington, DC 20585, e-mail donald.silawsky...

  18. Compressive properties of commercially available polyurethane foams as mechanical models for osteoporotic human cancellous bone

    National Research Council Canada - National Science Library

    Patel, Purvi S D; Shepherd, Duncan E T; Hukins, David W L

    2008-01-01

    ... of the low density PU foams are universally accepted as models for osteoporotic (OP) bone. The aim of this study was to determine whether low density PU foam might be suitable for mimicking human OP cancellous bone...

  19. 77 FR 65855 - Cancellation of Indianapolis Grain Inspection & Weighing Service, Inc. Designation; Selection of...

    Science.gov (United States)

    2012-10-31

    ... Grain Inspection, Packers and Stockyards Administration Cancellation of Indianapolis Grain Inspection... Indianapolis, IN Area AGENCY: Grain Inspection, Packers and Stockyards Administration, USDA. ACTION: Notice...), as amended. Indianapolis informed the Grain Inspection, Packers and Stockyards Administration (GIPSA...

  20. 76 FR 317 - Cancellation of Lewiston Grain Inspection Service, Inc. Designation; Opportunity for Designation...

    Science.gov (United States)

    2011-01-04

    ... Grain Inspection, Packers and Stockyards Administration Cancellation of Lewiston Grain Inspection..., Packers and Stockyards Administration, USDA. ACTION: Notice. SUMMARY: Lewiston Grain Inspection Service..., Packers and Stockyards Administration (GIPSA) that it would cease providing official inspection services...

  1. 75 FR 7570 - Federal Advisory Committee; Military Leadership Diversity Commission (MLDC); Meeting Cancellation

    Science.gov (United States)

    2010-02-22

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Federal Advisory Committee; Military Leadership Diversity Commission (MLDC); Meeting Cancellation AGENCY....150, the Department of Defense announces that the Military Leadership Diversity Commission (MLDC...

  2. Antenna Array for Passive Radar: Configuration Design and Adaptive Approaches to Disturbance Cancellation

    Directory of Open Access Journals (Sweden)

    Michelangelo Villano

    2013-01-01

    Full Text Available We consider the selection of an antenna array configuration, composed of a small number of omnidirectional elements, to be exploited for passive radar sensors. Based on properly identified pattern characteristics and design criteria for practical applications, a suitable planar configuration is selected that allows both angular selectivity and direct signal attenuation. The selected configuration is further optimized in terms of sidelobe level by resorting to appropriate amplitude tapering. Moreover, three different approaches are investigated for antenna-based adaptive disturbance cancellation, and a comparative performance analysis is carried out. Simulation results show that an effective clutter suppression is obtained if the direct signal from the transmitter is attenuated by means of spatial adaptive cancellation, and the multipath echoes from stationary obstacles are removed by means of temporal adaptive cancellation. In particular, the approach based on the Sidelobe Canceller is shown to yield good performance while requiring a limited system complexity.

  3. A novel sequential algorithm for clutter and direct signal cancellation in passive bistatic radars

    Science.gov (United States)

    Ansari, Farzad; Taban, Mohammad Reza; Gazor, Saeed

    2016-12-01

    Cancellation of clutter and multipath is an important problem in passive bistatic radars. Some important recent algorithms such as the ECA, the SCA and the ECA-B project the received signals onto a subspace orthogonal to both clutter and pre-detected target subspaces. In this paper, we generalize the SCA algorithm and propose a novel sequential algorithm for clutter and multipath cancellation in the passive radars. This proposed sequential cancellation batch (SCB) algorithm has lower complexity and requires less memory than the mentioned methods. The SCB algorithm can be employed for static and non-static clutter cancellation. The proposed algorithm is evaluated by computer simulation under practical FM radio signals. Simulation results reveal that the SCB provides an admissible performance with lower computational complexity.

  4. Research on adaptive acoustic echo cancellation algorithm in digital hearing aids

    Science.gov (United States)

    Ma, Min; Wang, Mingjiang; Hu, Jiebin

    2017-08-01

    At present, the study of acoustic echo cancellation (AEC) is mainly based on the adaptive acoustic echo cancellation algorithm. It is proved that the echo signal of the near-end microphone must be compensated by the time delay to achieve the purpose of echo cancellation, and the accuracy of the delay estimation affecting the final effect of echo cancellation. This paper proposes a combination of the normalized minimum mean square algorithm (NLMS) and the time delay estimation model to solve the echo problem in hearing aids. In this paper, using generalized cross correlation (GCC) to estimate time delay. In addition, using the energy, Teager-Kaiser Energy Operator (TKEO) and the signal correlation coefficient as the threshold value to detect the howling signal in digital hearing aids. Finally, the simulation and experimental results are given. The experiment proves that the method has good effect.

  5. Wiener variable step size and gradient spectral variance smoothing for double-talk-robust acoustic echo cancellation and acoustic feedback cancellation

    DEFF Research Database (Denmark)

    Gil-Cacho, Jose M.; Van Waterschoot, Toon; Moonen, Marc

    2014-01-01

    Double-talk (DT)-robust acoustic echo cancellation (AEC) and acoustic feedback cancellation (AFC) are needed in speech communication systems, e.g., in hands-free communication systems and hearing aids. In this paper, we derive a practical and computationally efficient algorithm based......-GSVS-FDAF-PEM-AFROW algorithm obtains outstanding robustness and smooth adaptation in highly adverse scenarios such as in bursting DT at high levels, and in a change of acoustic path during continuous DT. Similarly, in AFC simulations, the algorithm outperforms state-of-the-art algorithms when using a low-order near-end speech...

  6. Anomaly cancellation and gauge group of the standard model in NCG

    CERN Document Server

    Alvarez, Enrique; Martín, C P; Alvarez, Enrique

    1995-01-01

    It is well known that anomaly cancellation {\\it almost} determines the hypercharges in the standard model. A related (and somewhat more stronger) phenomenon takes place in Connes' NCG framework: unimodularity (a technical condition on elements of the algebra) is {\\it strictly} equivalent to anomaly cancellation (in the absence of right-handed neutrinos); and this in turn reduces the symmetry group of the theory to the standard SU(3)\\times SU(2) \\times U(1).

  7. Photonic-Enabled RF Canceller with Tunable Time-Delay Taps

    Science.gov (United States)

    2016-12-05

    reducing this SI in the analog domain, before the receiver’s low- noise amplifier (LNA), sat- uration can be avoided and spurious signals minimized in order...communications C-band, 191.50 to 196.25 THz, and had +10 dBm of output power . Our initial design utilized 20 such lasers, which resulted in 20 RF canceller...Photonic-Enabled RF Canceller with Tunable Time-Delay Taps Kenneth E. Kolodziej, Sivasubramaniam Yegnanarayanan, Bradley T. Perry MIT Lincoln

  8. Performance analysis of different adapative algorithms based on acoustic echo cancellation

    OpenAIRE

    Adapa, Nagaswaroopa; Bollu, Sravya

    2013-01-01

    In modern telecommunication systems like hands-free and teleconferencing systems, the problem arise during conversation is the creation of an acoustic echo. This problem degrades the quality of the information signal. All speech processing equipments like noise cancelling headphones and hearing aids should be able to filter different kinds of interfering signals and produce a clear sound to the listener. Currently, echo cancellation is a most interesting and challenging task in any communicat...

  9. Solution for Vehicles Noise Cancellation With Modification of LMS Adaptive Algorithm

    OpenAIRE

    Sri Arttini Dwi Prasetyowati; Bustanul Arifin; Eka Nuryanto Budi Susila

    2012-01-01

    The problems of noise cancelling systems are based on the specific characteristics of their sources. Therefore, the knowledge of each noise source should be represented prior to the excecution ofthe designed noise cancelling scheme. Since the noises emitted vary with the types of the passing vehicles, the scheme should be well adjusted automatically. The delay must be minimixed by managing the value of step size. Five representing types of noise producing vehicles (noise from: bus, truck, mot...

  10. On The Use of A Phase Modulation Method for Decorrelation in Acoustic Feedback Cancellation

    DEFF Research Database (Denmark)

    Guo, Meng; Jensen, Søren Holdt; Jensen, Jesper

    2012-01-01

    A major problem in using an adaptive filter in acoustic feedback cancellation systems is that the loudspeaker signal is correlated with the signals entering the microphones of the audio system, leading to biased filter estimates. One possible solution for reducing this problem is by means...... similar frequency shifting decorrelation method. We show that the phase modulation method is suitable for decorrelation in a hearing aid acoustic feedback cancellation system, although the frequency shifting method is in general slightly more effective....

  11. Cancellation of Glauber Gluon Exchange in the Double Drell-Yan Process

    Science.gov (United States)

    Diehl, Markus; Gaunt, Jonathan R.; Ostermeier, Daniel; Plößl, Peter; Schäfer, Andreas

    2016-06-01

    For any factorisation proof, a crucial step is a demonstration of the cancellation of so-called Glauber gluons. We summarise a recent paper in which we demonstrated this cancellation for double Drell-Yan production (the double parton scattering process in which a pair of electroweak gauge bosons is produced), both for the integrated cross section and for the cross section differential in the boson transverse momenta.

  12. Anisotropic Complementary Acoustic Metamaterial for Canceling out Aberrating Layers

    Directory of Open Access Journals (Sweden)

    Chen Shen

    2014-11-01

    Full Text Available In this paper, we investigate a type of anisotropic, acoustic complementary metamaterial (CMM and its application in restoring acoustic fields distorted by aberrating layers. The proposed quasi two-dimensional (2D, nonresonant CMM consists of unit cells formed by membranes and side branches with open ends. Simultaneously, anisotropic and negative density is achieved by assigning membranes facing each direction (x and y directions different thicknesses, while the compressibility is tuned by the side branches. Numerical examples demonstrate that the CMM, when placed adjacent to a strongly aberrating layer, could acoustically cancel out that aberrating layer. This leads to dramatically reduced acoustic field distortion and enhanced sound transmission, therefore virtually removing the layer in a noninvasive manner. In the example where a focused beam is studied, using the CMM, the acoustic intensity at the focus is increased from 28% to 88% of the intensity in the control case (in the absence of the aberrating layer and the CMM. The proposed acoustic CMM has a wide realm of potential applications, such as cloaking, all-angle antireflection layers, ultrasound imaging, detection, and treatment through aberrating layers.

  13. Throughput Performance of MC-CDMA HARQ Using ICI Cancellation

    Science.gov (United States)

    Fukuda, Kaoru; Nakajima, Akinori; Adachi, Fumiyuki

    Multi-carrier code division multiple access (MC-CDMA) is a promising wireless access technique for the next generation mobile communications systems, in which broadband packet data services will dominate. Hybrid automatic repeat request (HARQ) is an indispensable error control technique for high quality packet data transmission. The HARQ throughput performance of multi-code MC-CDMA degrades due to the presence of residual inter-code interference (ICI) after frequency-domain equalization (FDE). To reduce the residual ICI and improve the throughput performance, a frequency-domain soft interference cancellation (FDSIC) technique can be applied. An important issue is the generation of accurate residual ICI replica for FDSIC. In this paper, low-density parity-check coded (LDPC-coded) MC-CDMA HARQ is considered. We generate the residual ICI replica from a-posteriori log-likelihood ratio (LLR) of LDPC decoder output and evaluate, by computer simulation, the throughput performance in a frequency-selective Rayleigh fading channel. We show that if the residual ICI is removed, MC-CDMA can provide a throughput performance superior to orthogonal frequency division multiplexing (OFDM).

  14. Tunable scattering cancellation cloak with plasmonic ellipsoids in the visible

    Science.gov (United States)

    Fruhnert, Martin; Monti, Alessio; Fernandez-Corbaton, Ivan; Alù, Andrea; Toscano, Alessandro; Bilotti, Filiberto; Rockstuhl, Carsten

    2016-06-01

    The scattering cancellation technique is a powerful tool to reduce the scattered field from electrically small objects in a specific frequency window. The technique relies on covering the object of interest with a shell that scatters light into a far field of equal strength as the object but with a phase shift of π . The resulting destructive interference prohibits its detection in measurements that probe the scattered light. Whereas at radio or microwave frequencies feasible designs have been proposed that allow us to tune the operational frequency upon request, similar capabilities have not yet been explored in the visible. However, such an ability is necessary to capitalize on the technique in many envisioned applications. Here, we solve the problem and study the use of small metallic nanoparticles with an ellipsoidal shape as the material from which the shell is made to build an isotropic geometry. Changing the aspect ratio of the ellipsoids allows us to change the operational frequency. The basic functionality is explored with two complementary analytical approaches. Additionally, we present a powerful multiscattering algorithm that can be used to perform full-wave simulations of clusters of arbitrary particles. We utilize this method to analyze the scattering of the presented designs numerically. Herein we provide useful guidelines for the fabrication of this cloak with self-assembly methods by investigating the effects of disorder.

  15. It Is Time to Cancel Medicine's Social Contract Metaphor.

    Science.gov (United States)

    Harris, John M

    2017-09-01

    There is agreement that the complex relationship between medicine and society is best described as a metaphorical social contract and that professionalism is the medical profession's contribution to this contract. Metaphors can help clarify abstract concepts, but they can also be abused if the counterfactual attributes of a metaphor become attributed to its subject. This seems to be happening with medical professionalism, which has sometimes been reduced to a contracted deliverable and a bargaining chip. The undesirable attributes of the social contract metaphor may be hindering efforts to understand and teach medical professionalism.Despite its theoretical weaknesses, the social contract metaphor has historical credibility because of its alleged association with the 1847 Code of Medical Ethics and the subsequent ascension of regular (allopathic) medicine in the early 20th century. However, the record does not support an argument that the intended purpose of the 1847 Code was to create a social contract or that one ever arose. The alternative account that a contract did arise, but physicians were poor partners, is neither satisfying nor explanatory.As now used, medicine's social contract metaphor has serious theoretical and historic weaknesses. Medical educators should remove this narrow and overworked metaphor from their discussions of professionalism. By doing this, educators and the profession in general would only lose the ability to threaten themselves with the cancellation of their social contract. In return they would open the door to a more complex and fruitful consideration of medical professionalism and medicine's relationship with society.

  16. Strong expectations cancel locality effects: evidence from Hindi.

    Directory of Open Access Journals (Sweden)

    Samar Husain

    Full Text Available Expectation-driven facilitation (Hale, 2001; Levy, 2008 and locality-driven retrieval difficulty (Gibson, 1998, 2000; Lewis & Vasishth, 2005 are widely recognized to be two critical factors in incremental sentence processing; there is accumulating evidence that both can influence processing difficulty. However, it is unclear whether and how expectations and memory interact. We first confirm a key prediction of the expectation account: a Hindi self-paced reading study shows that when an expectation for an upcoming part of speech is dashed, building a rarer structure consumes more processing time than building a less rare structure. This is a strong validation of the expectation-based account. In a second study, we show that when expectation is strong, i.e., when a particular verb is predicted, strong facilitation effects are seen when the appearance of the verb is delayed; however, when expectation is weak, i.e., when only the part of speech "verb" is predicted but a particular verb is not predicted, the facilitation disappears and a tendency towards a locality effect is seen. The interaction seen between expectation strength and distance shows that strong expectations cancel locality effects, and that weak expectations allow locality effects to emerge.

  17. Strong expectations cancel locality effects: evidence from Hindi.

    Science.gov (United States)

    Husain, Samar; Vasishth, Shravan; Srinivasan, Narayanan

    2014-01-01

    Expectation-driven facilitation (Hale, 2001; Levy, 2008) and locality-driven retrieval difficulty (Gibson, 1998, 2000; Lewis & Vasishth, 2005) are widely recognized to be two critical factors in incremental sentence processing; there is accumulating evidence that both can influence processing difficulty. However, it is unclear whether and how expectations and memory interact. We first confirm a key prediction of the expectation account: a Hindi self-paced reading study shows that when an expectation for an upcoming part of speech is dashed, building a rarer structure consumes more processing time than building a less rare structure. This is a strong validation of the expectation-based account. In a second study, we show that when expectation is strong, i.e., when a particular verb is predicted, strong facilitation effects are seen when the appearance of the verb is delayed; however, when expectation is weak, i.e., when only the part of speech "verb" is predicted but a particular verb is not predicted, the facilitation disappears and a tendency towards a locality effect is seen. The interaction seen between expectation strength and distance shows that strong expectations cancel locality effects, and that weak expectations allow locality effects to emerge.

  18. Significance-aware filtering for nonlinear acoustic echo cancellation

    Science.gov (United States)

    Hofmann, Christian; Huemmer, Christian; Guenther, Michael; Kellermann, Walter

    2016-12-01

    This article summarizes and extends the recently proposed concept of Significance-Aware (SA) filtering for nonlinear acoustic echo cancellation. The core idea of SA filtering is to decompose the estimation of the nonlinear echo path into beneficially interacting subsystems, each of which can be adapted with high computational efficiency. The previously proposed SA Hammerstein Group Models (SA-HGMs) decompose the nonlinear acoustic echo path into a direct-path part, modeled by a Hammerstein Group Model (HGM) and a complementary part, modeled by a very efficient Hammerstein model. In this article, we furthermore propose a novel Equalization-based SA (ESA) structure, where the echo path is equalized by a linear filter to allow for an estimation of the loudspeaker nonlinearities by very small and efficient models. Additionally, we provide a novel in-depth analysis of the computational complexity of the previously proposed SA and the novel ESA filters and compare both SA filtering approaches to each other, to adaptive HGMs, and to linear filters, where fast partitioned-block frequency-domain realizations of the competing filter structures are considered. Finally, the echo reduction performance of the proposed SA filtering approaches is verified using real recordings from a commercially available smartphone. Beyond the scope of previous publications on SA-HGMs, the ability of the SA filters to generalize for double-talk situations is explicitly considered as well. The low complexity as well as the good echo reduction performance of both SA filters illustrate the potential of SA filtering in practice.

  19. Multicast in Femtocell Networks: A Successive Interference Cancellation Approach

    Directory of Open Access Journals (Sweden)

    Donglin Hu

    2014-09-01

    Full Text Available A femtocell is a small cellular base station (BS, typically used for serving approved users within a small coverage. In this paper, we investigate the problem of data multicast in femtocell networks that incorporates superposition coding (SC and successive interference cancellation (SIC. The problem is to decide the transmission schedule for each BS, as well as the power allocation for the SC layers, to achieve a sufficiently large SNR for each layer to be decodable with SIC at each user. Minimizing the total BS power consumption achieves the goal of “green” communications. We formulate a Mixed Integer Nonlinear Programming (MINLP problem, and then reformulate the problem into a simpler form. Upper and lower performance bounds on the total BS power consumption are derived. Finally, we consider three typical connection scenarios, and develop optimal and nearoptimal algorithms for the three scenarios. The proposed algorithms have low computational complexity, and outperform a heuristic scheme with considerable gains in our simulation study.

  20. Specimen size effect in the volumetric shrinkage of cancellous bone measured at two levels of dehydration.

    Science.gov (United States)

    Lievers, W Brent; Lee, Victoria; Arsenault, Simon M; Waldman, Stephen D; Pilkey, A Keith

    2007-01-01

    Water is commonly removed from bone to study its effect on mechanical behaviour; however, dehydration also alters the bone structure. To make matters worse, measuring structural changes in cancellous bone is complicated by a number of factors. Therefore, the goals of this study were to address these issues by (1) comparing Archimedes' method and a helium pycnometer as methods for measuring cancellous bone volume; (2) measuring the apparent dimensional and volumetric tissue shrinkage of cancellous bone at two levels of dehydration; and, (3) identifying whether a size effect exists in cancellous bone shrinkage. Cylindrical specimens (3, 5 and 8.3 mm diameters) of cancellous bone were taken from the distal bovine femur. The apparent dimensions of each cylindrical specimen were measured in a fully hydrated state (HYD), after drying at room temperature (AIR), and after oven drying at 105 degrees C (OVEN). Tissue volume measurements for those three hydration states were obtained using both a helium pycnometer and Archimedes' method. Aluminium foams, which mimic the cancellous structure, were used as controls. The results suggest that the helium pycnometer and Archimedes' method yield identical results in the HYD and AIR states, but that Archimedes' method under-predicts the nominal OVEN volume by incorporating the collagen-apatite porosity. A distinct size effect on volumetric shrinkage is observed (pshrinkage (2% and 7%) at the two dehydration levels is much smaller than the measured volumetric tissue shrinkage (16% and 29%), which results in a reduced dehydrated bone volume fraction.

  1. The finite element method for micro-scale modeling of ultrasound propagation in cancellous bone.

    Science.gov (United States)

    Vafaeian, B; El-Rich, M; El-Bialy, T; Adeeb, S

    2014-08-01

    Quantitative ultrasound for bone assessment is based on the correlations between ultrasonic parameters and the properties (mechanical and physical) of cancellous bone. To elucidate the correlations, understanding the physics of ultrasound in cancellous bone is demanded. Micro-scale modeling of ultrasound propagation in cancellous bone using the finite-difference time-domain (FDTD) method has been so far utilized as one of the approaches in this regard. However, the FDTD method accompanies two disadvantages: staircase sampling of cancellous bone by finite difference grids leads to generation of wave artifacts at the solid-fluid interface inside the bone; additionally, this method cannot explicitly satisfy the needed perfect-slip conditions at the interface. To overcome these disadvantages, the finite element method (FEM) is proposed in this study. Three-dimensional finite element models of six water-saturated cancellous bone samples with different bone volume were created. The values of speed of sound (SOS) and broadband ultrasound attenuation (BUA) were calculated through the finite element simulations of ultrasound propagation in each sample. Comparing the results with other experimental and simulation studies demonstrated the capabilities of the FEM for micro-scale modeling of ultrasound in water-saturated cancellous bone. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Computationally Efficient Partial Crosstalk Cancellation in Fast Time-Varying DSL Crosstalk Environments

    Directory of Open Access Journals (Sweden)

    Forouzan Amir R

    2007-01-01

    Full Text Available Line selection (LS, tone selection (TS, and joint tone-line selection (JTLS partial crosstalk cancellers have been proposed to reduce the online computational complexity of far-end crosstalk (FEXT cancellers in digital subscriber lines (DSL. However, when the crosstalk profile changes rapidly over time, there is an additional requirement that the partial crosstalk cancellers, particularly the LS and JTLS schemes, should also provide a low preprocessing complexity. This is in contrast to the case for perfect crosstalk cancellers. In this paper, we propose two novel channel matrix inversion methods, the approximate inverse (AI and reduced inverse (RI schemes, which reduce the recurrent complexity of the LS and JTLS schemes. Moreover, we propose two new classes of JTLS algorithms, the subsort and Lagrange JTLS algorithms, with significantly lower computational complexity than the recently proposed optimal greedy JTLS scheme. The computational complexity analysis of our algorithms shows that they provide much lower recurrent complexities than the greedy JTLS algorithm, allowing them to work efficiently in very fast time-varying crosstalk environments. Moreover, the analytical and simulation results demonstrate that our techniques are close to the optimal solution from the crosstalk cancellation point of view. The results also reveal that partial crosstalk cancellation is more beneficial in upstream DSL, particularly for short loops.

  3. Acoustic Echo and Noise Cancellation System for Hand-Free Telecommunication using Variable Step Size Algorithms

    Directory of Open Access Journals (Sweden)

    V. K. Gupta

    2013-04-01

    Full Text Available In this paper, acoustic echo cancellation with doubletalk detection system is implemented for a hand-free telecommunication system using Matlab. Here adaptive noise canceller with blind source separation (ANC-BSS system is proposed to remove both background noise and far-end speaker echo signal in presence of double-talk. During the absence of double-talk, far-end speaker echo signal is cancelled by adaptive echo canceller. Both adaptive noise canceller and adaptive echo canceller are implemented using LMS, NLMS, VSLMS and VSNLMS algorithms. The normalized cross-correlation method is used for double-talk detection. VSNLMS has shown its superiority over all other algorithms both for double-talk and in absence of double-talk. During the absence of double-talk it shows its superiority in terms of increment in ERLE and decrement in misalignment. In presence of double-talk, it shows improvement in SNR of near-end speaker signal.

  4. Programmable Real-Time Cancellation of GLONASS Interference with the Green Bank Telescope

    Science.gov (United States)

    Poulsen, A. J.; Jeffs, B. D.; Warnick, K. F.; Fisher, J. R.

    2005-12-01

    A programmable, real-time, digital signal processing (DSP), least-mean-squares (LMS) interference canceler was developed and demonstrated as a successful method of excising the GLONASS satellite L-band downlink signals from the 100 m Green Bank Telescope (GBT). This canceler has the potential for aiding the observation of redshifted OH lines near 1600 MHz in the presence of GLONASS signals. Our canceler approach is similar to experiments reported by Barnbaum and Bradley, Baan et al., and Kesteven et al. for mitigating ground-based radio frequency interference (RFI), but we add the new features of a tracking dish antenna to follow the satellite for improved cancellation performance, complex adaptive filter coefficients that reduce the required filter length, and a programmable delay line for bulk time delay correction. An analysis of LMS tracking performance for moving satellites is presented, and effective use of a reference antenna distantly located from the telescope is demonstrated. As is expected from the known properties of LMS cancelers, larger filter orders are shown to yield more reliable cancellation and are less sensitive to data time misalignment. GLONASS interference seen by the GBT was suppressed below the noise floor without corrupting a signal that simulated an astronomical source, even with rapid orbital transits and long integration times.

  5. Structural strength of cancellous specimens from bovine femur under cyclic compression

    Directory of Open Access Journals (Sweden)

    Kaori Endo

    2016-01-01

    Full Text Available The incidence of osteoporotic fractures was estimated as nine million worldwide in 2000, with particular occurrence at the proximity of joints rich in cancellous bone. Although most of these fractures spontaneously heal, some fractures progressively collapse during the early post-fracture period. Prediction of bone fragility during progressive collapse following initial fracture is clinically important. However, the mechanism of collapse, especially the gradual loss of the height in the cancellous bone region, is not clearly proved. The strength of cancellous bone after yield stress is difficult to predict since structural and mechanical strength cannot be determined a priori. The purpose of this study was to identify whether the baseline structure and volume of cancellous bone contributed to the change in cancellous bone strength under cyclic loading. A total of fifteen cubic cancellous bone specimens were obtained from two 2-year-old bovines and divided into three groups by collection regions: femoral head, neck, and proximal metaphysis. Structural indices of each 5-mm cubic specimen were determined using micro-computed tomography. Specimens were then subjected to five cycles of uniaxial compressive loading at 0.05 mm/min with initial 20 N loading, 0.3 mm displacement, and then unloading to 0.2 mm with 0.1 mm displacement for five successive cycles. Elastic modulus and yield stress of cancellous bone decreased exponentially during five loading cycles. The decrease ratio of yield stress from baseline to fifth cycle was strongly correlated with bone volume fraction (BV/TV, r = 0.96, p < 0.01 and structural model index (SMI, r = − 0.81, p < 0.01. The decrease ratio of elastic modulus from baseline to fifth cycle was also correlated with BV/TV (r = 0.80, p < 0.01 and SMI (r = − 0.78, p < 0.01. These data indicate that structural deterioration of cancellous bone is associated with bone strength after yield stress. This study suggests that

  6. Swine cortical and cancellous bone: histomorphometric and densitometric characterisation

    Directory of Open Access Journals (Sweden)

    Maria Elena Andreis

    2017-06-01

    Full Text Available Introduction: Swine bone morphology, composition and remodelling are similar to humans’, therefore they are considered good models in bone-related research. They have been used for several studies involving bone growth, bone and cartilage fractures and femoral head osteonecrosis. Nevertheless, the literature about pig normal bone features is incomplete. This work aims to fill the literature gaps on the microarchitecture and Bone Mineral Density (BMD of swine femoral diaphysis and distal epiphysis and tibial plateau and diaphysis. Materials and methods: Five hind limbs were collected from slaughtered 80-100 kg pigs. Microscopic analysis of cortical and cancellous bone from middle/distal femur and proximal/middle tibia was performed to determine basic histomorphometric parameters at different sites. Dual-energy X-Rays Absorptiometry was also employed to evaluate BMD. ANOVA and correlation between BMD, bone area (BA and cortical thickness were performed. Results and discussion: Diaphyseal cortical bone was mostly plexiform both in the tibia and the femur; primary/secondary osteons without clear organization were also found. Mean values for bone area, bone perimeter, trabecular width, number and separation and BMD at different anatomical sites were defined. No significant difference was found for these values at different anatomical sites. BMD proved to be positively correlated with cortical thickness (r=0,80; p<0,01. Despite the small sample size, these results seem homogeneous. They could therefore represent reference values for normal bone parameters in pigs. Applied anatomy and regenerative medicine, in fact, demand very precise information about bone micromorphology, composition and density to provide reliable indication in bone substitutes building. Moreover, since the interpretation of bone abnormalities is based on mastering normal bone characteristics, the definition of reference parameters is mandatory to avoid misinterpretation and

  7. Cortical and cancellous bone: age-related changes in morphologic features, fluid spaces, and calcium homeostasis in dogs

    Energy Technology Data Exchange (ETDEWEB)

    Simonet, W.T.; Bronk, J.T.; Pinto, M.R.; Williams, E.A.; Meadows, T.H.; Kelly, P.J.

    1988-02-01

    The changes in cortical and cancellous bone that occur with aging were studied by measuring morphologic and physiologic variables for both types of bone in dogs. The percentage area of cortical and cancellous bone, rate of bone formation, vascular volume, bone water, and volume of distribution of calcium tracer all showed statistically significant changes at the time of bone maturity. Canine cortical bone cell volume progressively decreased with advancing age, and cancellous bone cell volume significantly decreased between adult and old dogs. The volume of distribution technique can be used to determine the relative contributions of cortical and cancellous bone to the total body exchangeable calcium ion pool.

  8. Out-coupling of Longitudinal Photoacoustic Pulses by Mitigating the Phase Cancellation

    Science.gov (United States)

    Lee, Taehwa; Li, Qiaochu; Guo, L. Jay

    2016-01-01

    Waves of any kinds, including sound waves and light waves, can interfere constructively or destructively when they are overlapped, allowing for myriad applications. However, unlike continuous waves of a single frequency, interference of photoacoustic pulses is often overlooked because of their broadband characteristics and short pulse durations. Here, we study cancellation of two symmetric photoacoustic pulses radiated in the opposite direction from the same photoacoustic sources near a free surface. The cancellation occurs when one of the two pulses is reflected with polarity reversal from the free surface and catches up with the other. The cancellation effect, responsible for reduced signal amplitudes, is systematically examined by implementing a thin transparent matching medium of the same acoustic impedance. By changing the thickness of the transparent layer, the overlap of the two symmetric pulses is controlled. For optimized matching layers, the cancellation effect can be significantly reduced, while the resulting output waveform remains unchanged. Similar to the planar absorber, different dimensional absorbers including cylinders and spheres also exhibit the cancellation between the outward and inward waves. This work could provide further understanding of photoacoustic generation and a simple strategy for increasing photoacoustic signal amplitudes. PMID:26869360

  9. A harmonic cancellation technique for an ultrasound transducer excited by a switched-mode power converter.

    Science.gov (United States)

    Tang, Sai Chun; Clement, Gregory T

    2008-02-01

    The aim of this study is to evaluate the feasibility of using harmonic cancellation for a therapeutic ultrasound transducer excited by a switched-mode power converter without an additional output filter. A switching waveform without the third harmonic was created by cascading two switched-mode power inverter modules at which their output waveforms were pi/3 phase shifted from each other. A PSPICE simulation model for the power converter output stage was developed. The simulated results were in good agreement with the measurement. The waveform and harmonic contents of the acoustic pressure generated by a 1-MHz, self-focused piezoelectric transducer with and without harmonic cancellation have been evaluated. Measured results indicated that the acoustic third harmonicto- fundamental ratio at the focus was small (-48 dB) with harmonic cancellation, compared to that without harmonic cancellation (-20 dB). The measured acoustic levels of the fifth harmonic for both cases with and without harmonic cancellation also were small (-46 dB) compared to the fundamental. This study shows that it is viable to drive a piezoelectric ultrasound transducer using a switched-mode power converter without the requirement of an additional output filter in many high-intensity focused ultrasound (HIFU) applications.

  10. Analysis, Design, and Evaluation of Acoustic Feedback Cancellation Systems for Hearing Aids

    DEFF Research Database (Denmark)

    Guo, Meng

    2013-01-01

    Acoustic feedback problems occur when the output loudspeaker signal of an audio system is partly returned to the input microphone via an acoustic coupling through the air. This problem often causes significant performance degradations in applications such as public address systems and hearing aids....... In the worst case, the audio system becomes unstable and howling occurs. In this work, first we analyze a general multiple microphone audio processing system, where a cancellation system using adaptive filters is used to cancel the effect of acoustic feedback. We introduce and derive an accurate approximation...... in acoustic feedback cancellation for hearing aids. It utilizes a probe noise signal which is generated with a specific characteristic so that it can facilitate an unbiased adaptive filter estimation with fast tracking of feedback path variations/changes despite its low signal level. We show in a hearing aid...

  11. Performance of Turbo Interference Cancellation Receivers in Space-Time Block Coded DS-CDMA Systems

    Directory of Open Access Journals (Sweden)

    Emmanuel Oluremi Bejide

    2008-07-01

    Full Text Available We investigate the performance of turbo interference cancellation receivers in the space time block coded (STBC direct-sequence code division multiple access (DS-CDMA system. Depending on the concatenation scheme used, we divide these receivers into the partitioned approach (PA and the iterative approach (IA receivers. The performance of both the PA and IA receivers is evaluated in Rayleigh fading channels for the uplink scenario. Numerical results show that the MMSE front-end turbo space-time iterative approach receiver (IA effectively combats the mixture of MAI and intersymbol interference (ISI. To further investigate the possible achievable data rates in the turbo interference cancellation receivers, we introduce the puncturing of the turbo code through the use of rate compatible punctured turbo codes (RCPTCs. Simulation results suggest that combining interference cancellation, turbo decoding, STBC, and RCPTC can significantly improve the achievable data rates for a synchronous DS-CDMA system for the uplink in Rayleigh flat fading channels.

  12. Least mean square error difference minimum criterion for adaptive chaotic noise canceller

    Science.gov (United States)

    Zhang, Jia-Shu

    2007-02-01

    The least mean square error difference (LMS-ED) minimum criterion for an adaptive chaotic noise canceller is proposed in this paper. Different from traditional least mean square error minimum criterion in which the error is uncorrelated with the input vector, the proposed LMS-ED minimum criterion tries to minimize the correlation between the error difference and input vector difference. The novel adaptive LMS-ED algorithm is then derived to update the weights of adaptive noise canceller. A comparison between cancelling performances of adaptive least mean square (LMS), normalized LMS (NLMS) and proposed LMS-ED algorithms is simulated by using three kinds of chaotic noises. The simulation results clearly show that the proposed algorithm outperforms the LMS and NLMS algorithms in achieving small values of steady-state excess mean square error. Moreover, the computational complexity of the proposed LMS-ED algorithm is the same as that of the standard LMS algorithms.

  13. Effective strategies in improving operating room case delays and cancellations at an academic medical center.

    Science.gov (United States)

    Kaye, Alan David; McDowell, Joseph L; Diaz, James H; Buras, Jay A; Young, Amy E; Urman, Richard D

    2015-01-01

    Traditionally, the operating room (OR) in an academic medical center has faced numerous challenges to effective clinical productivity, including additional missions of teaching and research. Level 1 trauma poses more challenges related to the need for additional specialized personnel in anesthesia, surgery, and nursing. The present investigation explores lessons learned in efficiency, teamwork, and data evaluation at a level 1 academic teaching facility. The months of July 2012, July 2013, and July 2014 were selected for this study. Multiple strategies were implemented through the Operating Room Committee during this time in an effort to reduce the number of OR delays and cancellations. Case cancellations decreased significantly over the three-year period, while delays remained relatively stable. In July 2012, 15.0% of cases were cancelled and 10.2% were delayed. Cancellations decreased to 6.3% in 2013 and to 5.9% in 2014. The total number of cases completed per month increased each year throughout the study, from 577 in 2012 to 649 in 2013 to 842 in 2014. These results are remarkable in comparison to the greater-than 20% cancellation rate recorded in 2005 when the current OR leadership team first assessed OR efficiency. An increase in the number of cases completed per month likely can be attributed to a reduction in the number of case cancellations. Increased efficiency allows for more operations to be performed, leading to increased profitability and an increased ability of hospitals to continue caring for patients. We advocate the implementation of a comprehensive multidisciplinary strategy for sustained improvement in OR efficiency and utilization.

  14. Stationary echo canceling in velocity estimation by time-domain cross-correlation

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt

    1993-01-01

    The application of stationary echo canceling to ultrasonic estimation of blood velocities using time-domain cross-correlation is investigated. Expressions are derived that show the influence from the echo canceler on the signals that enter the cross-correlation estimator. It is demonstrated......, number of samples in the range gate, and number of A-lines employed in the estimation. Quantitative results calculated by a simple simulation program are given for the variation in probability from these parameters. An index reflecting the reliability of the estimate at hand can be calculated from...

  15. Adaptive Noise Cancellation System for Low Frequency Transmission of Sound in Open Fan Aircraft

    Directory of Open Access Journals (Sweden)

    Steven Griffin

    2013-01-01

    Full Text Available This paper describes the use of a structural/acoustic model of a section of a large aircraft to help define the sensor/actuator architecture that was used in a hardware demonstration of adaptive noise cancellation. Disturbances considered were representative of propeller-induced disturbances from an open fan aircraft. Controller on and controller off results from a hardware demonstration on a portion of a large aircraft are also included. The use of the model has facilitated the development of a new testing technique, closely related to modal testing, that can be used to find good structural actuator locations for adaptive noise cancellation.

  16. Capacitor Mismatch Error Cancellation Technique for a Successive Approximation A/D Converter

    DEFF Research Database (Denmark)

    Zheng, Zhiliang; Moon, Un-Ku; Steensgaard-Madsen, Jesper

    1999-01-01

    An error cancellation technique is described for suppressing capacitor mismatch in a successive approximation A/D converter. At the cost of a 50% increase in conversion time, the first-order capacitor mismatch error is cancelled. Methods for achieving top-plate parasitic insensitive operation...... are described, and the use of a gain- and offset-compensated opamp is explained. SWITCAP simulation results show that the proposed 16-bit SAR ADC can achieve an SNDR of over 91 dB under non-ideal conditions, including 1% 3 sigma nominal capacitor mismatch, 10-20% randomized parasitic capacitors, 66 dB opamp...

  17. Lightweight-compact variable-gap undulator with force cancellation system based on multipole monolithic magnets

    Science.gov (United States)

    Kinjo, Ryota; Kagamihata, Akihiro; Seike, Takamitsu; Kishimoto, Hikaru; Ohashi, Haruhiko; Yamamoto, Shigeru; Tanaka, Takashi

    2017-07-01

    A lightweight-compact variable-gap undulator (LCVGU) having the force-cancellation system based on the multipole monolithic magnets (MMMs) has been developed. The LCVGU is free from the heavy mechanical frames, which is a fundamental element specific to conventional variable-gap undulators (VGUs) because of a strong attractive force, and thus the cost and time for construction and installation are expected to be significantly reduced; the MMMs counteract the strong attractive force in a cost-effective manner. Results of mechanical tests and magnetic-field measurements of two prototype LCVGUs equipped with the proposed force cancellation system have revealed the comparable performance with the conventional VGUs.

  18. Propagation of two longitudinal waves in a cancellous bone with the closed pore boundary.

    Science.gov (United States)

    Mizuno, Katsunori; Nagatani, Yoshiki; Yamashita, Keisuke; Matsukawa, Mami

    2011-08-01

    Ultrasound propagation in cancellous bone (porous media) under the condition of closed pore boundaries was investigated. A cancellous bone and two plate-like cortical bones obtained from a racehorse were prepared. A water-immersion ultrasound technique in the MHz range and a three-dimensional elastic finite-difference time-domain (FDTD) method were used to investigate the waves. The experiments and simulations showed a clear separation of the incident longitudinal wave into fast and slow waves. The findings advance the evaluation of bones based on the two-wave phenomenon for in vivo assessment.

  19. Performance analysis of approximate Affine Projection Algorithm in acoustic feedback cancellation.

    Science.gov (United States)

    Nikjoo S, Mohammad; Seyedi, Amir; Tehrani, Arash Saber

    2008-01-01

    Acoustic feedback is an annoying problem in several audio applications and especially in hearing aids. Adaptive feedback cancellation techniques have attracted recent attention and show great promise in reducing the deleterious effects of feedback. In this paper, we investigated the performance of a class of adaptive feedback cancellation algorithms viz. the approximated Affine Projection Algorithms (APA). Mixed results were obtained with the natural speech and music data collected from five different commercial hearing aids in a variety of sub-oscillatory and oscillatory feedback conditions. The performance of the approximated APA was significantly better with music stimuli than natural speech stimuli.

  20. A relaxed condition for "perfect" cancellation of broadband noise in 3D enclosures

    Science.gov (United States)

    Yuan

    2000-06-01

    This paper presents a relaxed condition for "perfect" cancellation of broadband noise in 3D enclosures. On the basis of a truncated modal model, it can be shown that the primary and secondary paths belong to a same subspace if a certain condition is satisfied. There exists a finite impulse response (FIR) filter transfer function vector for perfect cancellation of the primary paths. The analytical result is verified numerically with an active noise control (ANC) system in a 3D rectangular enclosure. The proposed ANC scheme is shown to fit well into the framework of an existing multichannel least-mean squares (LMS) algorithm for adaptive implementation.

  1. Four-Tap RF Canceller Evaluation for Indoor In-Band Full-Duplex Wireless Operation

    Science.gov (United States)

    2016-07-24

    from 10 to 120 MHz centered at 2.45 GHz, and produced a combined analog system isolation greater than 85 dB. Index Terms— Adaptive canceller, analog...at the same time. This idea can be applied to 5G cellular , cognitive radio and wireless relay applications, among others, to reduce spectrum crowding...SOI for +20 dBm OFDM over 10 MHz. III. RESULTS The canceller was tuned to mitigate the effects of the indoor environment by using the adaptive

  2. Analysis of design parameters for crosstalk cancellation filters applied to different loudspeaker configurations

    DEFF Research Database (Denmark)

    Lacouture Parodi, Yesenia; Rubak, Per

    2011-01-01

    for crosstalk cancellation filters applied to different loudspeaker configurations has not yet been addressed systematically. A study of three different inversion techniques applied to several loudspeaker arrangements is documented. Least-squares approximations in the frequency and time domains are evaluated...... along with a crosstalk canceler based on minimum-phase approximation with a frequency-independent delay. The three methods were applied to loudspeaker configurations with two channels and the least-squares approaches to configurations with four channels. Several different span angles and elevations were...

  3. Adaptive Feedback Cancellation With Band-Limited LPC Vocoder in Digital Hearing Aids

    DEFF Research Database (Denmark)

    Ma, Guilin; Gran, Fredrik; Jacobsen, Finn

    2011-01-01

    , the estimate of the feedback path is biased. This so-called “bias problem” results in a large modeling error and a cancellation of the desired signal. This paper proposes a band-limited linear predictive coding based approach to reduce the bias. The idea is to replace the hearing-aid output with a synthesized......Feedback oscillation is one of the major issues with hearing aids. An effective way of feedback suppression is adaptive feedback cancellation, which uses an adaptive filter to estimate the feedback path. However, when the external input signal is correlated with the receiver input signal...

  4. 75 FR 9188 - Notice of Cancellation of Open Meeting of the Chief of Naval Operations (CNO) Executive Panel

    Science.gov (United States)

    2010-03-01

    ... Department of the Navy Notice of Cancellation of Open Meeting of the Chief of Naval Operations (CNO) Executive Panel AGENCY: Department of the Navy, DoD. ACTION: Notice of cancellation. SUMMARY: The Department..., announcing The CNO Executive Panel was scheduled to meet on March 11, 2010, to deliberate on the findings and...

  5. Higher number of pentosidine cross-links induced by ribose does not alter tissue stiffness of cancellous bone

    NARCIS (Netherlands)

    Willems, N.M.B.K.; Langenbach, G.E.J.; Stoop, R.; Toonder, J.M.J. den; Mulder, L.; Zentner, A.; Everts, V.

    2014-01-01

    The role of mature collagen cross-links, pentosidine (Pen) cross-links in particular, in the micromechanical properties of cancellous bone is unknown. The aim of this study was to examine nonenzymatic glycation effects on tissue stiffness of demineralized and non-demineralized cancellous bone. A

  6. 8 CFR 1003.43 - Motions to reopen for suspension of deportation and cancellation of removal pursuant to section...

    Science.gov (United States)

    2010-01-01

    ... Illegal Immigration Reform and Immigrant Responsibility Act (Pub. L. 104-208) (IIRIRA), as amended by... deportation and cancellation of removal pursuant to section 203(c) of NACARA and section 1505(c) of the LIFE... Procedure § 1003.43 Motions to reopen for suspension of deportation and cancellation of removal pursuant to...

  7. 49 CFR 40.203 - What problems cause a drug test to be cancelled unless they are corrected?

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false What problems cause a drug test to be cancelled... PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Problems in Drug Tests § 40.203 What problems cause a drug test to be cancelled unless they are corrected? (a) As the MRO, when a...

  8. 77 FR 21541 - Notice of Submission for OMB Review; Federal Student Aid; Teacher Cancellation Low Income Directory

    Science.gov (United States)

    2012-04-10

    ... Notice of Submission for OMB Review; Federal Student Aid; Teacher Cancellation Low Income Directory SUMMARY: The Teacher Cancellation Low Income (TCLI) Directory is the online data repository of elementary... Territory agencies report these schools to the TCLI Directory. DATES: Interested persons are invited to...

  9. Bone tissue stiffness in the mandibular condyle is dependent on the direction and density of the cancellous structure.

    NARCIS (Netherlands)

    Eijden, T.M. van; Ruijven, L.J. van; Giesen, E.B.W.

    2004-01-01

    Variation in the apparent stiffness of cancellous bone is generally ascribed to variation in cancellous structure and density, while the bone tissue stiffness is assumed to be constant. The purpose of the present study was to examine whether the bone tissue stiffness is dependent on the direction

  10. 75 FR 11899 - Notice of Cancellation of Customs Broker Licenses Due to Death of the License Holder

    Science.gov (United States)

    2010-03-12

    ... SECURITY Customs and Border Protection Notice of Cancellation of Customs Broker Licenses Due to Death of... Regulations at section 111.51(a), the following individual Customs broker licenses and any and all permits have been cancelled due to the death of the broker: License Name No. Port name Milton F. Whelan 09882...

  11. 77 FR 16249 - Notice of Cancellation of Customs Broker Licenses Due to Death of the License Holder

    Science.gov (United States)

    2012-03-20

    ... SECURITY U.S. Customs and Border Protection Notice of Cancellation of Customs Broker Licenses Due to Death... Federal Regulations at section 111.51(a), the following individual Customs broker licenses and any and all permits have been cancelled due to the death of the broker: Name License No. Port name Max Verne Lund...

  12. 76 FR 44033 - Notice of Cancellation of Customs Broker Licenses Due to Death of the License Holder

    Science.gov (United States)

    2011-07-22

    ... SECURITY U.S. Customs and Border Protection Notice of Cancellation of Customs Broker Licenses Due to Death... Federal Regulations at section 111.51(a), the following individual Customs broker licenses and any and all permits have been cancelled due to the death of the broker: License Name Port name Ofelia M. Pazos 20178...

  13. 76 FR 2918 - Notice of Cancellation of Customs Broker Licenses Due to Death of the License Holder

    Science.gov (United States)

    2011-01-18

    ... SECURITY U.S. Customs and Border Protection Notice of Cancellation of Customs Broker Licenses Due to Death... Federal Regulations at section 111.51(a), the following individual Customs broker license and any and all permits have been cancelled due to the death of the broker: Name License No. Port name Robert F. Barnes...

  14. 76 FR 22912 - Notice of Cancellation of Customs Broker Licenses Due to Death of the License Holder

    Science.gov (United States)

    2011-04-25

    ... SECURITY U.S. Customs and Border Protection Notice of Cancellation of Customs Broker Licenses Due to Death... 111.51(a), the following individual Customs broker licenses and any and all permits have been cancelled due to the death of the broker: Name License No. Port name Leandro U. Guevarra 16332 Los Angeles...

  15. 77 FR 21767 - Imidacloprid, Methomyl, and Oxamyl; Cancellation Order for Amendments To Terminate Uses

    Science.gov (United States)

    2012-04-11

    ... AGENCY Imidacloprid, Methomyl, and Oxamyl; Cancellation Order for Amendments To Terminate Uses AGENCY... containing imidacloprid, methomyl, and oxamyl, pursuant to section 6(f)(1) of the Federal Insecticide... voluntarily amend certain imidacloprid pesticide registrations to terminate use on almonds, to voluntarily...

  16. 48 CFR 252.239-7007 - Cancellation or termination of orders.

    Science.gov (United States)

    2010-10-01

    ... Cancellation or Termination Liability established by the CSA or other contractual document is based on... payments if in the opinion of the Contracting Officer the total of the payments is within the amount the...) Failure to agree shall be a dispute concerning a question of fact within the meaning of the Disputes...

  17. 7 CFR 301.91-6 - Compliance agreement and cancellation thereof.

    Science.gov (United States)

    2010-01-01

    ... may be cancelled orally or in writing by the inspector who is supervising its enforcement whenever the... agreement shall be a written agreement between a person engaged in such a business and Plant Protection and... confirmed in writing, as promptly as circumstances permit. Any person whose compliance agreement has been...

  18. 38 CFR 74.22 - What are the procedures for cancellation?

    Science.gov (United States)

    2010-07-01

    ... AFFAIRS (CONTINUED) VETERANS SMALL BUSINESS REGULATIONS Oversight Guidelines § 74.22 What are the... Notice of Proposed Cancellation Letter will set forth the specific facts and reasons for CVE's findings, and will notify the participant that it has 30 days from the date it receives the letter to submit a...

  19. Demineralized bone matrix and human cancellous bone enhance fixation of titanium implants

    DEFF Research Database (Denmark)

    Babiker, Hassan; Ding, Ming; Overgaard, Søren

    pain and bacterial or viral contamination. Thus, there is need for development of alternative bone graft materials. The use of osteoinductive materials such as demineralized bone matrix (DBM) alone or in combination with allograft or commercially available human cancellous bone (CB) may substitute allo...

  20. Learning contrast-invariant cancellation of redundant signals in neural systems.

    Directory of Open Access Journals (Sweden)

    Jorge F Mejias

    Full Text Available Cancellation of redundant information is a highly desirable feature of sensory systems, since it would potentially lead to a more efficient detection of novel information. However, biologically plausible mechanisms responsible for such selective cancellation, and especially those robust to realistic variations in the intensity of the redundant signals, are mostly unknown. In this work, we study, via in vivo experimental recordings and computational models, the behavior of a cerebellar-like circuit in the weakly electric fish which is known to perform cancellation of redundant stimuli. We experimentally observe contrast invariance in the cancellation of spatially and temporally redundant stimuli in such a system. Our model, which incorporates heterogeneously-delayed feedback, bursting dynamics and burst-induced STDP, is in agreement with our in vivo observations. In addition, the model gives insight on the activity of granule cells and parallel fibers involved in the feedback pathway, and provides a strong prediction on the parallel fiber potentiation time scale. Finally, our model predicts the existence of an optimal learning contrast around 15% contrast levels, which are commonly experienced by interacting fish.

  1. Method and apparatus for controlling LCL converters using asymmetric voltage cancellation techniques

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Hunter; Sealy, Kylee Devro; Sharp, Bryan Thomas; Gilchrist, Aaron

    2016-01-26

    A method and apparatus for LCL resonant converter control utilizing Asymmetric Voltage Cancellation is described. The methods to determine the optimal trajectory of the control variables are discussed. Practical implementations of sensing load parameters are included. Simple PI, PID and fuzzy logic controllers are included with AVC for achieving good transient response characteristics with output current regulation.

  2. 77 FR 70805 - Secretarial Commission on Indian Trust Administration and Reform Meeting Cancellation

    Science.gov (United States)

    2012-11-27

    ... Office of the Secretary Secretarial Commission on Indian Trust Administration and Reform Meeting... meeting of the Secretarial Commission on Indian Trust Administration and Reform (the Commission) scheduled.... is also cancelled. Notice of this meeting was published in the November 14, 2012, issue of the...

  3. Interlibrary Service Requests for Locally and Electronically Available Items: Patterns of Use, Users, and Canceled Requests

    Science.gov (United States)

    Page, Jessica R.; Kuehn, Jennifer

    2009-01-01

    As the use of the Ohio State University Libraries interlibrary services has increased, there have been more requests to borrow items that are already available to patrons locally, often in electronic format. Patterns relating to why patrons could not find locally available materials were identified in the record of canceled interlibrary requests…

  4. 76 FR 41219 - Reserve Forces Policy Board (RFPB); Cancellation of Meeting

    Science.gov (United States)

    2011-07-13

    ... of the Secretary Reserve Forces Policy Board (RFPB); Cancellation of Meeting AGENCY: Department of Defense; Office of the Secretary of Defense Reserve Forces Policy Board. ACTION: Notice of advisory...) 697-4486 (Voice), (703) 693-5371 (Facsimile), [email protected] . Mailing address is Reserve Forces Policy...

  5. An audit of day case cancellations in a Nigerian Tertiary Hospital ...

    African Journals Online (AJOL)

    Background: The concept of day case surgery puts into efficient utilisation scarce resources to derive numerous social and economic benefits. Frequent cancellation however erodes these gains and therefore serves as a way of assessing the efficient utilisation of day case resources including the factors responsible for ...

  6. Case cancellations on the day of surgery : an investigation in an Australian paediatric hospital

    NARCIS (Netherlands)

    Haana, Victoria; Sethuraman, Kannan; Stephens, Lisa; Rosen, Heather; Meara, John G.

    Background: This study investigates case cancellations on the intended day of surgery (DOS) at a paediatric hospital in Melbourne, Australia. The hospital in Melbourne treats over 32 000 inpatients annually and handles both elective and emergency cases. Methods: The data for this paper were

  7. 76 FR 74835 - Sunshine Act; Public Hearing Cancellation Notice; November 30, 2011

    Science.gov (United States)

    2011-12-01

    ... CORPORATION Sunshine Act; Public Hearing Cancellation Notice; November 30, 2011 OPIC's Sunshine Act notice of its Public Hearing in Conjunction with each Board meeting was published in the Federal Register... or submit written statements for the record; therefore, OPIC's public hearing scheduled for 2 p.m...

  8. 78 FR 33863 - Sunshine Act; Public Hearing, June 5, 2013; Cancellation

    Science.gov (United States)

    2013-06-05

    ...] [FR Doc No: 2013-13387] OVERSEAS PRIVATE INVESTMENT CORPORATION Sunshine Act; Public Hearing, June 5, 2013; Cancellation OPIC's Sunshine Act notice of its Public Hearing in Conjunction with each Board...; therefore, OPIC's public hearing scheduled for 2 p.m., June 5, 2013 in conjunction with OPIC's June 13, 2013...

  9. 76 FR 10073 - Sunshine Act Public Hearing Cancellation Notice; February 24, 2011

    Science.gov (United States)

    2011-02-23

    ... CORPORATION Sunshine Act Public Hearing Cancellation Notice; February 24, 2011 OPIC's Sunshine Act notice of its Public Hearing in Conjunction with each Board meeting was published in the Federal Register... testimony or submit written statements for the record; therefore, OPIC's public hearing scheduled for 2 PM...

  10. 77 FR 33497 - Sunshine Act; Public Hearing Cancellation Notice; June 6, 2012

    Science.gov (United States)

    2012-06-06

    ... CORPORATION Sunshine Act; Public Hearing Cancellation Notice; June 6, 2012 OPIC's Sunshine Act notice of its Public Hearing in Conjunction with each Board meeting was published in the Federal Register (77 FR 13158... record; therefore, OPIC's public hearing scheduled for 2 p.m., March 21, 2012 in conjunction with OPIC's...

  11. 76 FR 64978 - Sunshine Act; Public Hearing Cancellation Notice; October 19, 2011

    Science.gov (United States)

    2011-10-19

    ... CORPORATION Sunshine Act; Public Hearing Cancellation Notice; October 19, 2011 OPIC's Sunshine Act notice of its Public Hearing in Conjunction with each Board meeting was published in the Federal Register... or submit written statements for the record; therefore, OPIC's public hearing scheduled for 2 PM...

  12. 77 FR 34029 - National Security Education Board Members Meeting; Cancellation of Meeting

    Science.gov (United States)

    2012-06-08

    ... of the Secretary National Security Education Board Members Meeting; Cancellation of Meeting AGENCY.... SUMMARY: On May 11, 2012 (77 FR 27739), Department of Defense announced a meeting of the National Security... and National Security Education Office, 1101 Wilson Boulevard, Suite 1210, Arlington, VA 22209...

  13. 34 CFR 674.58 - Cancellation for service in an early childhood education program.

    Science.gov (United States)

    2010-07-01

    ... complete academic year, or its equivalent. (5) In order to qualify for cancellation, the borrower's salary... of qualifying service, for each complete academic year, or its equivalent, of full-time teaching... addresses the children's cognitive (including language, early literacy, and early mathematics), social...

  14. 75 FR 5584 - Fipronil; Product Cancellation Order and Amendment to Terminate Uses

    Science.gov (United States)

    2010-02-03

    ... AGENCY Fipronil; Product Cancellation Order and Amendment to Terminate Uses AGENCY: Environmental... amendment to terminate uses of products containing the pesticide fipronil, pursuant to section 3 of the.... These are not the last fipronil products registered for use in the United States. Any distribution, sale...

  15. LC-filter Resonance Cancellation with DPWM Inverters in Adjustable Speed Drives

    DEFF Research Database (Denmark)

    Vadstrup, Casper; Wang, Xiongfei; Blaabjerg, Frede

    2015-01-01

    Discontinuous PWM methods cannot easily be used in LC-filtered inverters for adjustable speed drives, as it causes resonances in the filter. This paper present a new method to cancel the resonance and compares this method to previously proposed methods. Wide band gap devices are entering the market...

  16. 36 CFR 223.40 - Cancellation for environmental protection or inconsistency with plans.

    Science.gov (United States)

    2010-07-01

    ... Renewable Resources Planning Act of 1974, as amended. Such provision shall provide for reasonable... environmental protection or inconsistency with plans. 223.40 Section 223.40 Parks, Forests, and Public Property... Contracts Contract Conditions and Provisions § 223.40 Cancellation for environmental protection or...

  17. 49 CFR 40.199 - What problems always cause a drug test to be cancelled?

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false What problems always cause a drug test to be... TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Problems in Drug Tests § 40.199 What problems always cause a drug test to be cancelled? (a) As the MRO, when the laboratory discovers a “fatal flaw” during...

  18. 7 CFR 301.55-5 - Issuance and cancellation of certificates and limited permits.

    Science.gov (United States)

    2010-01-01

    ...) ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE DOMESTIC QUARANTINE NOTICES South American Cactus Moth § 301.55-5 Issuance and cancellation of certificates and limited permits. (a) An... determines that: 4 Services of an inspector may be requested by contacting local offices of Plant Protection...

  19. 24 CFR 1710.118 - Receipt, agent certification and cancellation page.

    Science.gov (United States)

    2010-04-01

    ..., DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT (INTERSTATE LAND SALES REGISTRATION PROGRAM) LAND REGISTRATION... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Receipt, agent certification and cancellation page. 1710.118 Section 1710.118 Housing and Urban Development Regulations Relating to Housing and...

  20. Multi-user interference cancellation schemes for carrier frequency offset compensation in uplink OFDMA

    DEFF Research Database (Denmark)

    Nguyen, Huan Cong; De Carvalho, Elisabeth; Prasad, Ramjee

    2014-01-01

    receiver and a reference frequency-domain multi-user interference cancellation scheme. In a particular scenario, a maximum CFO of up to 40% of the subcarrier spacing can be tolerated, and the CFO-free performance is maintained in the OFDMA uplink. The proposed schemes outperform the multi-user interference...

  1. 76 FR 29013 - Sunshine Act Notice; Public Hearing Cancellation, May 25, 2011

    Science.gov (United States)

    2011-05-19

    ... CORPORATION Sunshine Act Notice; Public Hearing Cancellation, May 25, 2011 OPIC's Sunshine Act notice of its..., Number 90, Page 27103) on May 10, 2011. No requests were received to provide testimony or submit written statements for the record; therefore, OPIC's public hearing scheduled for 2 PM, May 25, 2011 in conjunction...

  2. Interference Cancellation Schemes for Single-Carrier Block Transmission with Insufficient Cyclic Prefix

    Directory of Open Access Journals (Sweden)

    Hayashi Kazunori

    2008-01-01

    Full Text Available Abstract This paper proposes intersymbol interference (ISI and interblock interference (IBI cancellation schemes at the transmitter and the receiver for the single-carrier block transmission with insufficient cyclic prefix (CP. The proposed scheme at the transmitter can exterminate the interferences by only setting some signals in the transmitted signal block to be the same as those of the previous transmitted signal block. On the other hand, the proposed schemes at the receiver can cancel the interferences without any change in the transmitted signals compared to the conventional method. The IBI components are reduced by using previously detected data signals, while for the ISI cancellation, we firstly change the defective channel matrix into a circulant matrix by using the tentative decisions, which are obtained by our newly derived frequency domain equalization (FDE, and then the conventional FDE is performed to compensate the ISI. Moreover, we propose a pilot signal configuration, which enables us to estimate a channel impulse response whose order is greater than the guard interval (GI. Computer simulations show that the proposed interference cancellation schemes can significantly improve bit error rate (BER performance, and the validity of the proposed channel estimation scheme is also demonstrated.

  3. 75 FR 22404 - Clofencet; Notice of Receipt of Request to Voluntarily Cancel Certain Pesticide Registrations

    Science.gov (United States)

    2010-04-28

    ... products containing the pesticide clofencet. The request would delete clofencet use as a plant growth regulator registered for use in the production of hybrid wheat seed. The request would terminate the last... registrant, Monsanto Company, to cancel certain clofencet product registrations. Clofencet is a plant growth...

  4. On Intercell Interference and Its Cancellation in Cellular Multicarrier CDMA Systems

    Directory of Open Access Journals (Sweden)

    Simon Plass

    2007-11-01

    Full Text Available The handling of intercell interference at the cell border area is a strong demand in future communication systems to guarantee efficient use of the available bandwidth. Therefore, this paper focuses on the application of iterative intercell interference cancellation schemes in cellular multicarrier code division multiple access (MC-CDMA systems at the receiver side for the downlink. First, the influence of the interfering base stations to the total intercell interference is investigated. Then, different concepts for intercell interference cancellation are described and investigated for scenarios with several interfering cells. The first approach is based on the use of the hard decision of the demodulator to reconstruct the received signals. This does not require the higher amount of complexity compared to the second approach which is based on the use of the more reliable soft values from the decoding process. Furthermore, the extrinsic information as a reliability measure of this soft iterative cancellation process is investigated in more detail based on the geographical position of the mobile terminal. Both approaches show significant performance gains in the severe cell border area. With the soft intercell interference cancellation scheme, it is possible to reach the single-user bound. Therefore, the intercell interference can be almost eliminated.

  5. On Intercell Interference and Its Cancellation in Cellular Multicarrier CDMA Systems

    Directory of Open Access Journals (Sweden)

    Plass Simon

    2008-01-01

    Full Text Available Abstract The handling of intercell interference at the cell border area is a strong demand in future communication systems to guarantee efficient use of the available bandwidth. Therefore, this paper focuses on the application of iterative intercell interference cancellation schemes in cellular multicarrier code division multiple access (MC-CDMA systems at the receiver side for the downlink. First, the influence of the interfering base stations to the total intercell interference is investigated. Then, different concepts for intercell interference cancellation are described and investigated for scenarios with several interfering cells. The first approach is based on the use of the hard decision of the demodulator to reconstruct the received signals. This does not require the higher amount of complexity compared to the second approach which is based on the use of the more reliable soft values from the decoding process. Furthermore, the extrinsic information as a reliability measure of this soft iterative cancellation process is investigated in more detail based on the geographical position of the mobile terminal. Both approaches show significant performance gains in the severe cell border area. With the soft intercell interference cancellation scheme, it is possible to reach the single-user bound. Therefore, the intercell interference can be almost eliminated.

  6. 75 FR 877 - Cancellation of the South Valley Facilities Expansion Project-Clark County, NV

    Science.gov (United States)

    2010-01-06

    ... Bureau of Reclamation Cancellation of the South Valley Facilities Expansion Project-- Clark County, NV... (NOI) to prepare an Environmental Impact Statement (EIS) for the South Valley Facilities Expansion... Bureau of Reclamation, Lower Colorado Region, P.O. Box 61470, Boulder City, NV 89006-1470. SUPPLEMENTARY...

  7. Increased presence of capillaries next to remodeling sites in adult human cancellous bone

    DEFF Research Database (Denmark)

    Kristensen, Helene Bjoerg; Andersen, Thomas Levin; Marcussen, Niels

    2013-01-01

    Vascularization is a prerequisite for osteogenesis in a number of situations, including bone development, fracture healing, and cortical bone remodeling. It is unknown whether a similar link exists between cancellous bone remodeling and vascularization. Here, we show an association between remode...

  8. 76 FR 75599 - Advisory Committee on International Economic Policy; Notice of Meeting Cancellation

    Science.gov (United States)

    2011-12-02

    ... Committee on International Economic Policy; Notice of Meeting Cancellation The meeting of the Advisory Committee on International Economic Policy (Public Notice 7654) scheduled for 2 to 4 p.m. on Thursday... additional information, contact Deputy Outreach Coordinator Tiffany Enoch, Office of Economic Policy Analysis...

  9. 77 FR 65234 - Notice of Intention To Cancel Registrations of Certain Investment Advisers Pursuant to the...

    Science.gov (United States)

    2012-10-25

    ... From the Federal Register Online via the Government Publishing Office SECURITIES AND EXCHANGE COMMISSION Notice of Intention To Cancel Registrations of Certain Investment Advisers Pursuant to the Investment Advisers Act of 1940 Notice is given that the Securities and Exchange Commission (the ``Commission...

  10. A Tablet-PC-Based Cancellation Test Assessing Executive Functions in Older Adults

    NARCIS (Netherlands)

    Wu, Y.H.; Vidal, J.S.; de Rotrou, J.; Sikkes, S.A.M.; Rigaud, A.S.; Plichart, M.

    2015-01-01

    Objective To examine older adults' performance on a newly developed tablet-PC-based cancellation test (e-CT) and to study its psychometric properties. Methods 94 older adults with normal cognitive functioning were recruited. The effects of age, education, sex, and experience with computer-based

  11. 78 FR 57379 - Cancellation of Pesticides for Non-Payment of Year 2013 Registration Maintenance Fees

    Science.gov (United States)

    2013-09-18

    ... are subject to cancellation by order and without a hearing. The Food, Agriculture, Conservation, and... XX-X-X Lawn Food with 0.069% Bifenthrin Insecticide 007405-00051 Chemi-Cap Hosp-I-Septic G Surface... 043813-00023 Evipol 360SL 043813-00024 Evipol Technical 043813-00029 Xamox Technical 043813-00030 Xamox...

  12. 5 CFR 870.502 - Basic insurance: Waiver/cancellation of insurance.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Basic insurance: Waiver/cancellation of insurance. 870.502 Section 870.502 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES' GROUP LIFE INSURANCE PROGRAM Coverage § 870.502 Basic...

  13. 5 CFR 870.505 - Optional insurance: Waiver/cancellation of insurance.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Optional insurance: Waiver/cancellation of insurance. 870.505 Section 870.505 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES' GROUP LIFE INSURANCE PROGRAM Coverage...

  14. 77 FR 27226 - Aldicarb; Cancellation Order for Amendments To Terminate Uses

    Science.gov (United States)

    2012-05-09

    ..., peanuts, soybeans, sugar beets, and sweet potatoes, effective as of December 31, 2014. These are not the..., Dry Beans, Peanuts, Soybeans, Sugar Beets, and Sweet Potatoes. Table 2 of this unit includes the name... beet, and sweet potato cancellations that are subject of this notice is December 31, 2014. Any...

  15. Delayed-X Lms Algorithm: AN Efficient Anc Algorithm Utilizing Robustness of Cancellation Path Model

    Science.gov (United States)

    Kim, H.-S.; Park, Y.

    1998-05-01

    In conventional ANC (Active Noise Control), the cancellation path is usually modelled by a FIR filter with many coefficients. In this study, a Delayed-X LMS algorithm is investigated of which the computational load is much less than that of the Filtered-X LMS method for a long duct or narrow band noise cancellation application. This algorithm is based on the hypothesis that the cancellation path model for the Filtered-X LMS method does not have to be accurate and can be represented by a delay in such cases. The steady state weight vector solution in the presence of model error is investigated to show the validity of using an erroneous simplification. The ADE (Adaptive Delay Estimation) method is proposed for effective delay estimation of the cancellation path, which can be used with the Delayed-X LMS algorithm on-line or off-line. Simulation and experimental results demonstrate the effectiveness of the Delayed-X LMS algorithm for the specified applications.

  16. Cancellous bone structure of iliac crest biopsies following 370 days of head-down bed rest

    DEFF Research Database (Denmark)

    Thomsen, Jesper Skovhus; Morukov, Boris V.; Vico, Laurence

    2005-01-01

    INTRODUCTION: Static bone histomorphometry was applied to existing iliac bone sections originating from a 370-d 5 degrees head-down bed rest experiment. This bed rest experiment is the longest ever to have been conducted. We hypothesized that bed rest would decrease cancellous bone volume fractio...

  17. 76 FR 55385 - Notice of Receipt of Requests To Voluntarily Cancel Certain Pesticide Registrations

    Science.gov (United States)

    2011-09-07

    ... Silverado Fenoxaprop-p-ethyl. Herbicide. 000264-00699 Rhino Brand MCPA,2-ethylhexyl ester, Herbicide... Requests for Cancellation Registration No. Product name Chemical name 000264-00438 Bronate MCPA,2-ethylhexyl ester, Herbicide. Bromoxynil octanoate. 000264-00477 Buctril + Bromoxynil octanoate, Atrazine...

  18. 77 FR 1679 - Notice of Receipt of Requests To Voluntarily Cancel Certain Pesticide Registrations

    Science.gov (United States)

    2012-01-11

    ... Requests for Cancellation EPA Reg. No. Product name Active ingredients 000264-00438 Bronate Herbicide MCPA... Atrazine. Herbicide. 000264-00586 Sedagri Batril Bromoxynil octanoate. 20W Herbicide. 000264-00699 Rhino Brand MCPA, 2-ethylhexyl Herbicide. este; Bromoxynil octanoate; Heptanoic acid, 2,6-dibromo-4...

  19. 77 FR 64794 - Cancellation of the National Agricultural Research, Extension, Education, and Economics Advisory...

    Science.gov (United States)

    2012-10-23

    ..., Extension, Education, and Economics Advisory Board Meeting AGENCY: Research, Education, and Economics, USDA..., Extension, Education, and Economics Advisory Board scheduled for October 23-25, 2012 has been cancelled. The..., and Economics Advisory Board; telephone: (202) 720-3684; fax: (202) 720-6199; or email: Robert.Burk...

  20. 77 FR 75157 - Notice of Receipt of a Request To Voluntarily Cancel Certain Pesticide Registrations

    Science.gov (United States)

    2012-12-19

    ... VBC Esbiol Concentrate. 73049-399 VBC Esbiothrin. ] Table 2--End-Use Product Registrations With... Table 1 of this unit. The allethrin series of pyrethroid insecticides includes bioallethrin (PC code... cancellation of their end use products effective December 31, 2016. Table 1--Technical Product Registrations...

  1. 78 FR 11881 - Notice of Receipt of Requests To Voluntarily Cancel Certain Pesticide Registrations

    Science.gov (United States)

    2013-02-20

    ... Metasystox-R-Spray Oxydemeton-methyl Concentrate. WA060005 MSR Spray Oxydemeton-methyl Concentrate. Table 2... company number and 24(c) number) in Table 1 of this unit. Unless the Agency determines that there are... intends to issue an order in the Federal Register canceling all of the affected registrations. Table 1...

  2. 7 CFR 319.8-3 - Refusal and cancellation of permits.

    Science.gov (United States)

    2010-01-01

    ... INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE FOREIGN QUARANTINE NOTICES Foreign Cotton and Covers Conditions of Importation and Entry of Cotton and Covers § 319.8-3 Refusal and cancellation of permits. (a... Northwest Mexico, or that other conditions exist therein that would increase the hazard of pest introduction...

  3. 78 FR 69172 - Defense Trade Advisory Group; Notice of Cancellation of Open Meeting

    Science.gov (United States)

    2013-11-18

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF STATE Defense... of Cancellation of meeting. SUMMARY: The notice references Public Notice 8515 published in the..., SA-1, 12th Floor, Directorate of Defense Trade Controls, Bureau of Political Military Affairs, U.S...

  4. Opportunistic Interference Cancellation Evaluation in Cognitive Radios under Power Control Strategies

    DEFF Research Database (Denmark)

    Suriano, Ferdinando; De Rango, Floriano; Popovski, Petar

    2013-01-01

    This work considers a cognitive radio (secondary system) that operates under the interference of a WiMAX-like legacy (primary) system. The secondary terminals have knowledge of the codebooks used in the primary system and can apply Opportunistic Interference Cancellation (OIC): if the channel...

  5. [Postponement and cancellation of physician visits among Icelanders: extent and explanations].

    Science.gov (United States)

    Vilhjálmsson, Rúnar

    2011-10-01

    Equal access to health care is a central goal in socialized health systems like the one in Iceland. Previous research in Iceland indicates considerable individual and group differences in access to health care. The study maps the distribution of postponement and cancellation of physician care among Icelandic adults and considers a number of potential explanations. The data come from a national postal health survey of Icelandic adults, age 18-75, who were randomly drawn from the National Register. 1532 individuals responded to the survey yielding a 60% response rate. 22% of the respondents had postponed or cancelled a physician visit they thought they needed in the past 6 months. The study found considerable variations in postponement rates. Postponement was positively related to younger age, full employment, financial difficulties, high out-of-pocket health care costs, inflexible daily schedules (fixed roles), dissatisfaction with last physician visit, and the number of chronic medical conditions experienced. Postponement or cancellation of medical care is fairly common among Icelandic adults, although considerable individual and group differences in postponement are observed. The results raise concerns, as equal access to care is a central goal of the Icelandic health care system. It is incumbent upon health authorities to pursue effective ways to equalize access to medical care and prevent postponement and cancellation of needed services.

  6. Recombinant Human Parathyroid Hormone (1–34) [Teriparatide] Improves Both Cortical and Cancellous Bone Structure

    National Research Council Canada - National Science Library

    Jiang, Yebin; Zhao, Jenny J; Mitlak, Bruce H; Wang, Ouhong; Genant, Harry K; Eriksen, Erik F

    2003-01-01

    ... (rDNA origin) injection [rhPTH(1–34), TPTD] to improve both cancellous and cortical bone in a subset of women enrolled in the Fracture Prevention Trial of postmenopausal women with osteoporosis after a mean treatment time of 19 months...

  7. 21 CFR 1.235 - How and when do you cancel your facility's registration information?

    Science.gov (United States)

    2010-04-01

    ... example, you do not have reasonable access to the Internet through any of the methods described in § 1.231... have reasonable access to the Internet through any of the methods described in § 1.231(a), you may... CD-ROM format must use ISO 9660 (CD-R or CD-RW) data format. (2) Cancellation files must be submitted...

  8. 78 FR 64255 - Advisory Committee for Computer and Information Science and Engineering; Cancellation of Meeting

    Science.gov (United States)

    2013-10-28

    ... From the Federal Register Online via the Government Publishing Office NATIONAL SCIENCE FOUNDATION Advisory Committee for Computer and Information Science and Engineering; Cancellation of Meeting SUMMARY: As a result of the impact of the recent government shutdown, the National Science Foundation is...

  9. 75 FR 57785 - Notice of Receipt of Request to Voluntarily Cancel Certain Pesticide Registrations

    Science.gov (United States)

    2010-09-22

    ..., human health, and agricultural advocates; the chemical industry; pesticide users; and members of the... determines that continued use of the pesticide would pose an unreasonable adverse effect on the environment... AGENCY Notice of Receipt of Request to Voluntarily Cancel Certain Pesticide Registrations AGENCY...

  10. 78 FR 12313 - Notice of Receipt of Requests To Voluntarily Cancel Certain Pesticide Registrations

    Science.gov (United States)

    2013-02-22

    ... interest to a wide range of stakeholders including ] environmental, human health, and agricultural... Administrator determines that continued use of the pesticide would pose an unreasonable adverse effect on the... AGENCY Notice of Receipt of Requests To Voluntarily Cancel Certain Pesticide Registrations AGENCY...

  11. 77 FR 18813 - Rescission of Previously Issued Cancellation Order for Methyl Parathion Product Registration

    Science.gov (United States)

    2012-03-28

    ..., human health, and agricultural advocates; the chemical industry; pesticide users; and members of the... effect and are not otherwise affected by this action. DATES: The cancellation of the methyl parathion... FURTHER INFORMATION CONTACT: Kelly Ballard, Pesticide Re-evaluation Division (7508P), Office of Pesticide...

  12. 75 FR 20009 - Development of NRC's Safety Culture Policy Statement: Cancellation of Public Workshops Scheduled...

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    2010-04-16

    ... COMMISSION Development of NRC's Safety Culture Policy Statement: Cancellation of Public Workshops Scheduled... forging a consensus around the objectives, strategies, activities and measures that enhance safety culture... culture common terminology effort comprised of: (1) Development of a common safety culture definition; and...

  13. 77 FR 71584 - Agency Information Collection Activities; Comment Request; Loan Cancellation in the Federal...

    Science.gov (United States)

    2012-12-03

    ... From the Federal Register Online via the Government Publishing Office ] DEPARTMENT OF EDUCATION... borrower's eligibility to receive certain cancellation benefits and to prevent fraud and abuse of program... would likely result in a loss of Federal money due to waste, fraud and abuse. Dated: November 27, 2012...

  14. On the Effect of Self-Interference Cancelation in MultiHop Wireless Networks

    Directory of Open Access Journals (Sweden)

    Ephremides Anthony

    2010-01-01

    Full Text Available In a wireless network, the problem of self-interference arises when a node transmits and receives simultaneously in the same frequency band. So far only two extreme approaches to circumvent this problem were thoroughly investigated in the literature. The first one prevents any node to transmit and receive simultaneously which may lead to a too conservative design. The second one assumes perfect self-interference cancelation which can be too optimistic since it ignores all possible technological limitations. To fill this gap, we provide a method based on complementary geometric programming for evaluating the gains achievable at the network layer when the network nodes employ self-interference cancelation techniques with different degrees of accuracy. The gains are evaluated in terms of average sum rate and average network congestion by using a network utility maximization framework. The method provides insights into the behavior of different network topologies when self-interference cancellation is employed in nodes. In addition, it can be used to assess the required degrees of accuracy of the self-interference in order to achieve substantial benefits. Thus, from a network design perspective, the proposed method is very beneficial. Numerical results suggest that the benefits from self-interference cancelation are more pronounced in tandem wireless network setups in which the network nodes are located in a linear grid.

  15. LECTURE CANCELLED - Academic Training Lecture: Implications of LHC Data to New Physics (1/3)

    CERN Multimedia

    2013-01-01

    PLEASE NOTE THAT THIS LECTURE IS CANCELLED by Alex Pomarol Clotet (Universitat Autònoma de Barcelona, Spain). Monday, March 18, 2013 from 11:00 to 12:00 (Europe/Zurich) at CERN ( 4-3-006 - TH Conference Room ) More information here.

  16. 76 FR 75799 - General Administrative Regulations; Mutual Consent Cancellation; Food Security Act of 1985...

    Science.gov (United States)

    2011-12-05

    ... Consent Cancellation; Food Security Act of 1985, Implementation; Denial of Benefits; and Ineligibility for... Crop Insurance Act. (1) Section 1764 of the Food Security Act of 1985 (Pub. L. 99-198); (2) 21 U.S.C...-- 3. Remove and Reserve subpart F, Food Security Act of 1985, Implementation; Denial of Benefits. 4...

  17. CMOS upconversion mixer with filterless carrier feedthrough cancelation and output power tuning

    NARCIS (Netherlands)

    Sanchez Gaspariano, Luis Abraham; Annema, Anne J.; Muniz Montero, Carlos; Diaz Sanchez, Alejandro

    2014-01-01

    The synthesis, design and implementation of a CMOS upconversion mixer that both can adjust, by means of a DC voltage control, its output power and that cancels the carrier feedthrough is presented. Aiming at very low cost medical implant applications, a prototype of the architecture was implemented

  18. 75 FR 34117 - Notice of Receipt of Requests to Voluntarily Cancel Certain Pesticide Registrations

    Science.gov (United States)

    2010-06-16

    ... Cancellation Registration No. Product Name Active Ingredients 000004-00059 Bonide Rose & Malathion Flower Dust... Bioallethrin and Crawling MGK 264 Insect Killer Permethrin 000498-00170 Spraypak Wasp & d-Allethrin Hornet... Prallethrin Linalool Permethrin 002915-00065 Industrial Insect MGK 264 Spray III Piperonyl Butoxide Pyrethrins...

  19. Coordinated Direct and Relay Transmission with Interference Cancelation in Wireless Systems

    DEFF Research Database (Denmark)

    Thai, Chan; Popovski, Petar

    2011-01-01

    Two-way relaying schemes in wireless systems obtain throughput gain by utilizing two features (1) jointly serve two communication flows, thus implementing network coding and (2) use of information that is a priori known to cancel interference and obtain the desired signal. Based on these principl...

  20. Progressive femoral cortical and cancellous bone density loss after uncemented tapered-design stem fixation

    Science.gov (United States)

    Nowak, Tobias E; Haeberle, Lothar; Mueller, Lars P; Kress, Alexander; Voelk, Michael; Pfander, David; Forst, Raimund; Schmidt, Rainer

    2010-01-01

    Background Aseptic implant loosening and periprosthetic bone loss are major problems after total hip arthroplasty (THA). We present an in vivo method of computed tomography (CT) assisted osteodensitometry after THA that differentiates between cortical and cancellous bone density (BD) and area around the femoral component. Method Cortical and cancellous periprosthetic femoral BD (mg CaHA/mL), area (mm2) and contact area between the prothesis and cortical bone were determined prospectively in 31 patients 10 days, 1 year, and 6 years after uncemented THA (mean age at implantation: 55 years) using CT-osteodensitometry. Results 6 years postoperatively, cancellous BD had decreased by as much as 41% and cortical BD by up to 27% at the metaphyseal portion of the femur; this decrease was progressive between the 1-year and 6-year examinations. Mild cortical hypertrophy was observed along the entire length of the diaphysis. No statistically significant changes in cortical BD were observed along the diaphysis of the stem. Interpretation Periprosthetic CT-assisted osteodensitometry has the technical ability to discriminate between cortical and cancellous bone structures with respect to strain-adapted remodeling. Continuous loss of cortical and cancellous BD at the femoral metaphysis, a homeostatic cortical strain configuration, and mild cortical hypertrophy along the diaphysis suggest a diaphyseal fixation of the implanted stem. CT-assisted osteodensitometry has the potential to become an effective instrument for quality control in THA by means of in vivo determination of periprosthetic BD, which may be a causal factor in implant loosening after THA. PMID:20180716

  1. Quantification of age-related changes in the structure model type and trabecular thickness of human tibial cancellous

    DEFF Research Database (Denmark)

    Ding, Ming; Hvid, I

    2000-01-01

    Structure model type and trabecular thickness are important characteristics in describing cancellous bone architecture. It has been qualitatively observed that a radical change of trabeculae from plate-like to rod-like occurs in aging, bone remodeling, and osteoporosis. Thickness of trabeculae has......) cancellous bone. In this study, 160 human proximal tibial cancellous bone specimens from 40 normal donors, aged 16 to 85 years, were collected. These specimens were micro-computed tomography (micro-CT) scanned, then the micro-CT images were segmented using optimal thresholds. From accurate 3-D data sets...

  2. Anabolic Responses of an Adult Cancellous Bone Site to Prostaglandin E2 in the Rat

    Science.gov (United States)

    Ito, Hiroshi; Ke, Hua Zhu; Jee, Webster S. S.; Sakou, Takashi

    1993-01-01

    The objects of this study were to determine: (1) the response of a non-growing cancellous bone site to daily prostaglandin E2 (PGE2) administration; and (2) the differences in the effects of daily PGE2, administration in growing (proximal tibial metaphysis, PTM) and non-growing cancellous bone sites (distal tibial metaphysis, DTM). Seven-month-old male Sprague-Dawley rats were given daily subcutaneous injections of 0, 1, 3 and 6 mg PGE2/kg per day for 60, 120 and 180 days. The static and dynamic histomorphometric analyses were performed on double-fluorescent labeled undecalcified distal tibial metaphyses (DTM). No age-related changes were found in static and dynamic histomorphometry of DTM cancellous bone between 7 and 13 months of age. The DTM of 7-month-old (basal controls) rats consisted of a 24.5 +/- 7.61%-metaphyseal cancellous bone mass, and a thick trabeculae (92 +/- 12 micro-m). It also had a very low tissue-base bone formation rate (3.0 +/- 7.31%/year). Exogenous PGE2 administration produced the following transient changes in a dose-response manner between zero and 60 days: (1) increased trabecular bone mass and improved architecture (increased trabecular bone area, width and number, and decreased trabecular separation); (2) increased trabecular interconnections: (3) increased bone formation parameters; and (4) decreased eroded perimeter. A new steady state with more cancellous bone mass and higher bone turnover was observed from day 60 onward, The elevated bone mass induced by the first 60 days of PGE2 treatment was maintained by another 60 and 120 days with continuous daily PGE2 treatment. When these findings were compared to those previously reported for the PTM, we found that the DTM was much more responsive to PGE2 treatment than the PTM. Percent trabecular bone area and tissue based bone formation rate increased significantly more in DTM as compared to PTM after the 60 days of 6 mg PGE2 treatment. These observations indicate that a non

  3. Study of Noise Canceling Performance of Feedforward Fuzzy-Based ANC System under Non-Causal Condition

    DEFF Research Database (Denmark)

    Mojallali, Hamed; Izadi-Zamanabadi, Roozbeh; Amini, Rouzbeh

    of noise canceling performance of feed-forward fuzzy-based ANC systems for ducts under non-causal condition is presented. For this purpose, we use fuzzy filtered-x algorithm as an adaptive filter and the results are compared with classical filteredx algorithm which is employed under the same conditions......Feed-forward active noise control (ANC) systems act as adaptive systems to control and cancel undesired signals and noises. If the delay in the noise canceling subsystems increases more than the delays in the primary path, non-causal condition will occur in these systems. In this paper, study....... Analysis shows that ANC systems using fuzzy algorithm has better efficiency for noise cancellation in non-causal condition....

  4. Combined Effect of Random Transmit Power Control and Inter-Path Interference Cancellation on DS-CDMA Packet Mobile Communications

    Science.gov (United States)

    Kudoh, Eisuke; Ito, Haruki; Wang, Zhisen; Adachi, Fumiyuki

    In mobile communication systems, high speed packet data services are demanded. In the high speed data transmission, throughput degrades severely due to severe inter-path interference (IPI). Recently, we proposed a random transmit power control (TPC) to increase the uplink throughput of DS-CDMA packet mobile communications. In this paper, we apply IPI cancellation in addition to the random TPC. We derive the numerical expression of the received signal-to-interference plus noise power ratio (SINR) and introduce IPI cancellation factor. We also derive the numerical expression of system throughput when IPI is cancelled ideally to compare with the Monte Carlo numerically evaluated system throughput. Then we evaluate, by Monte-Carlo numerical computation method, the combined effect of random TPC and IPI cancellation on the uplink throughput of DS-CDMA packet mobile communications.

  5. Joint Digital Self-interference Cancellation in Full-duplex Radios under IQ Imbalance and Transmitter Non-linearity

    Directory of Open Access Journals (Sweden)

    Zhou Meijing

    2018-01-01

    Full Text Available RF imperfections can significantly degrade the performance of full-duplex wireless communication system by introducing non-idealities and random effects, which make it difficult to cancel the self-interference completely. In this paper, we first address the adverse benefits of both the transmitter non-linearity and the IQ imbalance. Then on the basis of these, a joint digital self-interference cancellation scheme is proposed, in which not only the effect of IQ imbalance and power amplifier non-linearity individually, but also the comprehensive function of them are taken into account. Furthermore, the simulation is implemented in the MATLAB platform using standard WiFi 802.11ac PHYs. The results show that the proposed canceller can eliminate more compared with other cancellation schemes, and the overall self-interference attenuation can attain 108dB, which makes the residual self-interference closer to the noise floor.

  6. Cancel and rethink in the Wason selection task: further evidence for the heuristic-analytic dual process theory.

    Science.gov (United States)

    Wada, Kazushige; Nittono, Hiroshi

    2004-06-01

    The reasoning process in the Wason selection task was examined by measuring card inspection times in the letter-number and drinking-age problems. 24 students were asked to solve the problems presented on a computer screen. Only the card touched with a mouse pointer was visible, and the total exposure time of each card was measured. Participants were allowed to cancel their previous selections at any time. Although rethinking was encouraged, the cards once selected were rarely cancelled (10% of the total selections). Moreover, most of the cancelled cards were reselected (89% of the total cancellations). Consistent with previous findings, inspection times were longer for selected cards than for nonselected cards. These results suggest that card selections are determined largely by initial heuristic processes and rarely reversed by subsequent analytic processes. The present study gives further support for the heuristic-analytic dual process theory.

  7. Performance analysis of power-efficient adaptive interference cancelation in fading channels

    KAUST Repository

    Radaydeh, Redha Mahmoud Mesleh

    2010-12-01

    This paper analyzes the performance of a -steering scheme for highly correlated receive antennas in the presence of statistically unordered co-channel interferers over multipath fading channels. An adaptive activation of receive antennas according to the interfering signals fading conditions is considered in the analysis. Analytical expressions for various system performance measures, including the outage probability, average error probability of different signaling schemes, and raw moments of the combined signal-to-interference-plus-noise ratio (SINR) are obtained in exact forms. Numerical and simulation results for the performance-complexity tradeoff of this scheme is presented and then compared with that of full-size arbitrary interference cancelation and no cancelation scenarios. ©2010 IEEE.

  8. A new FPGA-driven P-HIFU system with harmonic cancellation technique

    Science.gov (United States)

    Wu, Hao; Shen, Guofeng; Su, Zhiqiang; Chen, Yazhu

    2017-03-01

    This paper introduces a high intensity focused ultrasound system for ablation using switch-mode power amplifiers with harmonic cancellation technique eliminating the 3rdharmonic and all even harmonics. The efficiency of the amplifier is optimized by choosing different parameters of the harmonic cancellation technique. This technique requires double driving signals, and specific signal waveform because of the full-bridge topology. The new FPGA-driven P-HIFU system has 200 channels of phase signals that can form 100 output channels. An FPGA chip is used to generate these signals, and each channel has a phase resolution of 2 ns, less than one degree. The output waveform of the amplifier, voltage waveform across the transducer, shows fewer harmonic components.

  9. Frequency Estimation in Iterative Interference Cancellation Applied to Multibeam Satellite Systems

    Directory of Open Access Journals (Sweden)

    Ducasse A

    2007-01-01

    Full Text Available This paper deals with interference cancellation techniques to mitigate cochannel interference on the reverse link of multibeam satellite communication systems. The considered system takes as a starting point the DVB-RCS standard with the use of convolutional coding. The considered algorithm consists of an iterative parallel interference cancellation scheme which includes estimation of beamforming coefficients. This algorithm is first derived in the case of a symbol asynchronous channel with time-invariant carrier phases. The aim of this article is then to study possible extensions of this algorithm to the case of frequency offsets affecting user terminals. The two main approaches evaluated and discussed here are based on (1 the use of block processing for estimation of beamforming coefficients in order to follow carrier phase variations and (2 the use of single-user frequency offset estimations.

  10. Cancellation of Collisional Frequency Shifts in Optical Lattice Clocks with Rabi Spectroscopy

    CERN Document Server

    Lee, Sangkyung; Lee, Won-Kyu; Yu, Dai-Hyuk

    2015-01-01

    We analyze both the s- and p-wave collision induced frequency shifts and propose a over-$\\pi$ pulse scheme to cancel the shifts in optical lattice clocks interrogated by a Rabi pulse. The collisional frequency shifts are analytically solved as a function of the pulse area and the inhomogeneity of the Rabi frequencies. Experimentally measured collisional frequency shifts in an Yb optical lattice clock are in good agreement with the analytical calculations. Based on our analysis, the over-$\\pi$ pulse combined with a small inhomogeneity below 0.1 allows a fractional uncertainty on a level of $10^{-18}$ in both Sr and Yb optical lattice clocks by canceling the collisional frequency shift. \\end{abstract}

  11. Successive Interference Cancellation for DS-Optical PPM-CDMA Systems

    Science.gov (United States)

    Alsowaidi, N.; Eltaif, Tawfig; Mokhtar, M. R.

    2016-06-01

    In this paper we introduce a successive interference cancellation (SIC) scheme for direct sequence optical code division multiple access (DS-OCDMA) systems using pulse position modulation (PPM). Considering double-padded modified prime code (DPMPC) as a signature sequence code, results show that the system has better performance in terms of both capacity and bit error rate (BER) as compared to the one without cancellation scheme, where the system with SIC scheme can support up to 88 users while the system without SIC scheme can support only 38 users at similar BER=10-9. Although the receiver sensitivity is affected by the overlapping between users, which limits the system performance, the theoretical analysis of this issue indicates the influence of the size of M-ary PPM on OCDMA system. Hence, the BER value is still sufficient for good system performance.

  12. Cancellation of collisional frequency shifts in optical lattice clocks with Rabi spectroscopy

    Science.gov (United States)

    Lee, Sangkyung; Park, Chang Yong; Lee, Won-Kyu; Yu, Dai-Hyuk

    2016-03-01

    We analyze both the s- and p-wave collision induced frequency shifts and propose an over-π pulse scheme to cancel the shifts in optical lattice clocks interrogated by a Rabi pulse. The collisional frequency shifts are analytically solved as a function of the pulse area and the inhomogeneity of the Rabi frequencies. Experimentally measured collisional frequency shifts in an Yb optical lattice clock are in good agreement with the analytical calculations. Based on our analysis, the over-π pulse combined with a small inhomogeneity below 0.1 allows a fractional uncertainty on a level of 10-18 in both Sr and Yb optical lattice clocks by canceling the collisional frequency shift.

  13. CMOS Baseline Tracking and Cancellation Instrumentation for Nanoparticle-Coated Chemiresistors.

    Science.gov (United States)

    Rairigh, D J; Warnell, G A; Chao Xu; Zellers, E T; Mason, A J

    2009-10-01

    Chemiresistor (CR) sensors and sensor arrays coated with thiolate-monolayer-protected gold nanoparticle (MPN) interfaces show great promise as detectors in gas-chromatographic microsystems with applications in biomedical and environmental analysis including breath biomarkers of disease. This paper describes a new readout circuit that overcomes the wide range of baseline resistances and drift in baseline values inherent to MPN-coated CRs to achieve a 57 ppm readout resolution. The 0.5-mum CMOS circuit operates at 5 V and provides a response resolution of 74 muV. It can cancel baseline voltages from 0.3 to 4.3 V with an accuracy of 4.2 mV and can track and compensate for drifts up to 30 mV/min. Performance was verified with MPN-coated CRs, where drift was measured and effectively cancelled. The circuit topology and size support an on-chip MPN-coated CR sensor array.

  14. Self‐Interference Cancellation for Shared Band Transmission in Nonlinear Satellite Communication Channels

    Directory of Open Access Journals (Sweden)

    Sooyeob Jung

    2017-12-01

    Full Text Available For efficient spectral utilization of satellite channels, a shared band transmission technique is introduced in this paper. A satellite transmits multiple received signals from a gateway and terminal in the common frequency band by superimposing the signals. To improve the power efficiency as well as the spectral efficiency, a travelling wave tube amplifier in the satellite should operate near the saturation level. This causes a nonlinear distortion of the superimposed transmit signal. Without mitigating this nonlinear effect, the self‐interference cannot be properly cancelled and the desired signal cannot be demodulated. Therefore, an adaptive compensation scheme for nonlinearity is herein proposed with the proper operation scenario. It is shown through simulations that the proposed shared band transmission approach with nonlinear compensation and self‐interference cancellation can achieve an acceptable system performance in nonlinear satellite channels.

  15. Countermeasure against blinding attacks on low-noise detectors with a background-noise-cancellation scheme

    Science.gov (United States)

    Lee, Min Soo; Park, Byung Kwon; Woo, Min Ki; Park, Chang Hoon; Kim, Yong-Su; Han, Sang-Wook; Moon, Sung

    2016-12-01

    We developed a countermeasure against blinding attacks on low-noise detectors with a background-noise-cancellation scheme in quantum key distribution (QKD) systems. Background-noise cancellation includes self-differencing and balanced avalanche photon diode (APD) schemes and is considered a promising solution for low-noise APDs, which are critical components in high-performance QKD systems. However, its vulnerability to blinding attacks has been recently reported. In this work, we propose a countermeasure that prevents this potential security loophole from being used in detector blinding attacks. An experimental QKD setup is implemented and various tests are conducted to verify the feasibility and performance of the proposed method. The obtained measurement results show that the proposed scheme successfully detects occurring blinding-attack-based hacking attempts.

  16. Combination of Adaptive Feedback Cancellation and Binaural Adaptive Filtering in Hearing Aids

    Directory of Open Access Journals (Sweden)

    Anthony Lombard

    2009-01-01

    Full Text Available We study a system combining adaptive feedback cancellation and adaptive filtering connecting inputs from both ears for signal enhancement in hearing aids. For the first time, such a binaural system is analyzed in terms of system stability, convergence of the algorithms, and possible interaction effects. As major outcomes of this study, a new stability condition adapted to the considered binaural scenario is presented, some already existing and commonly used feedback cancellation performance measures for the unilateral case are adapted to the binaural case, and possible interaction effects between the algorithms are identified. For illustration purposes, a blind source separation algorithm has been chosen as an example for adaptive binaural spatial filtering. Experimental results for binaural hearing aids confirm the theoretical findings and the validity of the new measures.

  17. Frequency Estimation in Iterative Interference Cancellation Applied to Multibeam Satellite Systems

    Directory of Open Access Journals (Sweden)

    J. P. Millerioux

    2007-07-01

    Full Text Available This paper deals with interference cancellation techniques to mitigate cochannel interference on the reverse link of multibeam satellite communication systems. The considered system takes as a starting point the DVB-RCS standard with the use of convolutional coding. The considered algorithm consists of an iterative parallel interference cancellation scheme which includes estimation of beamforming coefficients. This algorithm is first derived in the case of a symbol asynchronous channel with time-invariant carrier phases. The aim of this article is then to study possible extensions of this algorithm to the case of frequency offsets affecting user terminals. The two main approaches evaluated and discussed here are based on (1 the use of block processing for estimation of beamforming coefficients in order to follow carrier phase variations and (2 the use of single-user frequency offset estimations.

  18. Adaptive co-channel interference cancelation for power-limited applications

    KAUST Repository

    Radaydeh, Redha Mahmoud Mesleh

    2010-09-01

    This paper proposes an adaptive co-channel interference -steering algorithm for highly correlated receive antenna channels with an aim of reducing the power consumption at the receiver. With this algorithm, the receiver activates as many antennas as necessary to maintain the residual total interference instantaneous power within a tolerable range, which can be set to guarantee a target performance level. The mode of operation does not require perfect knowledge of the statistical ordering of interfering signals instantaneous powers, which further reduces the complexity of implementation. It is shown that the arbitrary interference cancelation technique and no cancelation scenario can be studied as limiting cases of the proposed scheme. Analytical expressions for the statistics of the residual total interference instantaneous power are derived, which are then used to obtain results for the average number of active antennas and system outage performance. Numerical studies supported by simulations are presented to clarify the usefulness of the proposed scheme. ©2010 IEEE.

  19. Cancellation of artifacts in ECG signals using a normalized adaptive neural filter.

    Science.gov (United States)

    Wu, Yunfeng; Rangayyan, Rangaraj M; Ng, Sin-Chun

    2007-01-01

    Denoising electrocardiographic (ECG) signals is an essential procedure prior to their analysis. In this paper, we present a normalized adaptive neural filter (NANF) for cancellation of artifacts in ECG signals. The normalized filter coefficients are updated by the steepest-descent algorithm; the adaptation process is designed to minimize the difference between second-order estimated output values and the desired artifact-free ECG signals. Empirical results with benchmark data show that the adaptive artifact canceller that includes the NANF can effectively remove muscle-contraction artifacts and high-frequency noise in ambulatory ECG recordings, leading to a high signal-to-noise ratio. Moreover, the performance of the NANF in terms of the root-mean-squared error, normalized correlation coefficient, and filtered artifact entropy is significantly better than that of the popular least-mean-square (LMS) filter.

  20. Investigation of Diesel’s Residual Noise on Predictive Vehicles Noise Cancelling using LMS Adaptive Algorithm

    Science.gov (United States)

    Arttini Dwi Prasetyowati, Sri; Susanto, Adhi; Widihastuti, Ida

    2017-04-01

    Every noise problems require different solution. In this research, the noise that must be cancelled comes from roadway. Least Mean Square (LMS) adaptive is one of the algorithm that can be used to cancel that noise. Residual noise always appears and could not be erased completely. This research aims to know the characteristic of residual noise from vehicle’s noise and analysis so that it is no longer appearing as a problem. LMS algorithm was used to predict the vehicle’s noise and minimize the error. The distribution of the residual noise could be observed to determine the specificity of the residual noise. The statistic of the residual noise close to normal distribution with = 0,0435, = 1,13 and the autocorrelation of the residual noise forming impulse. As a conclusion the residual noise is insignificant.

  1. On-line adaptive line frequency noise cancellation from a nuclear power measuring channel

    Directory of Open Access Journals (Sweden)

    Qadir Javed

    2011-01-01

    Full Text Available On-line software for adaptively canceling 50 Hz line frequency noise has been designed and tested at Pakistan Research Reactor 1. Line frequency noise causes much problem in weak signals acquisition. Sometimes this noise is so dominant that original signal is totally corrupted. Although notch filter can be used for eliminating this noise, but if signal of interest is in close vicinity of 50 Hz, then original signal is also attenuated and hence overall performance is degraded. Adaptive noise removal is a technique which could be employed for removing line frequency without degrading the desired signal. In this paper line frequency noise has been eliminated on-line from a nuclear power measuring channel. The adaptive LMS algorithm has been used to cancel 50 Hz noise. The algorithm has been implemented in labVIEW with NI 6024 data acquisition card. The quality of the acquired signal has been improved much as can be seen in experimental results.

  2. Adler-Bardeen theorem and manifest anomaly cancellation to all orders in gauge theories

    Energy Technology Data Exchange (ETDEWEB)

    Anselmi, Damiano [Pisa Univ. (Italy). Dipt. di Fisica ' ' Enrico Fermi' ' ; INFN, Sezione di Pisa (Italy)

    2014-10-15

    We reconsider the Adler-Bardeen theorem for the cancellation of gauge anomalies to all orders, when they vanish at one loop. Using the Batalin-Vilkovisky formalism and combining the dimensional-regularization technique with the higher-derivative gauge invariant regularization, we prove the theorem in the most general perturbatively unitary renormalizable gauge theories coupled to matter in four dimensions, and we identify the subtraction scheme where anomaly cancellation to all orders is manifest, namely no subtractions of finite local counterterms are required from two loops onwards. Our approach is based on an order-by-order analysis of renormalization, and, differently from most derivations existing in the literature, does not make use of arguments based on the properties of the renormalization group. As a consequence, the proof we give also applies to conformal field theories and finite theories. (orig.)

  3. Reasons for Cancellation of Cases on the Day of Surgery-A Prospective Study

    Directory of Open Access Journals (Sweden)

    Rakesh Garg

    2009-01-01

    We believe that many of the on-the-day surgery cancellations of elective surgery were potentially avoidable. We observed that cancellations due to lack of theatre time were not only a scheduling problem but were mainly caused by surgeons underestimating the timeneeded for the operation. The requirement of the instruments necessary for scheduled surgical listshould be discussed a day prior to planned OR list and arranged. The non-availability of the surgeon should be informed in time so that another case is substituted in that slot. All patients who have met PACU discharge criteria must be discharged promptly to prevent delay in shifting out of the operated patient. Day care patients should be counseled adequately to report on time. Computerized scheduling should be utilized to create a realistic elective schedule. Audit should be carried out at regular intervals to find out the effective functioning of the operation theatre.

  4. Mutual associations among microstructural, physical and mechanical properties of human cancellous bone

    DEFF Research Database (Denmark)

    Ding, Ming; Odgaard, A; Danielsen, CC

    2002-01-01

    were tested to determine the mechanical properties and the physical/compositional properties were evaluated. The type of structure together with anisotropy correlated well with Young's modulus of human tibial cancellous bone. The plate-like structure reflected high mechanical stress and the rod......-like structure low mechanical stress. There was a strong correlation between the type of trabecular structure and the bone-volume fraction. The most effective microstructural properties for predicting the mechanical properties of cancellous bone seem to differ with age.......Previous studies have shown that low-density, rod-like trabecular structures develop in regions of low stress, whereas high-density, plate-like trabecular structures are found in regions of high stress. This phenomenon suggests that there may be a close relationship between the type of trabecular...

  5. Ranking Based Locality Sensitive Hashing Enabled Cancelable Biometrics: Index-of-Max Hashing

    OpenAIRE

    Jin, Zhe; Lai, Yen-Lung; Hwang, Jung-Yeon; Kim, Soohyung; Teoh, Andrew Beng Jin

    2017-01-01

    In this paper, we propose a ranking based locality sensitive hashing inspired two-factor cancelable biometrics, dubbed "Index-of-Max" (IoM) hashing for biometric template protection. With externally generated random parameters, IoM hashing transforms a real-valued biometric feature vector into discrete index (max ranked) hashed code. We demonstrate two realizations from IoM hashing notion, namely Gaussian Random Projection based and Uniformly Random Permutation based hashing schemes. The disc...

  6. Successive Interference Cancellation for DS-CDMA Systems with Transmit Diversity

    Directory of Open Access Journals (Sweden)

    Li Wei

    2004-01-01

    Full Text Available We introduce a new successive interference cancellation (SIC technique for direct sequence code division multiple access (DS-CDMA systems with transmit diversity. The transmit diversity is achieved with a space-time block code (STBC. In our work we first consider hard decision SIC with an STBC, and then investigate the performance of soft decision SIC with an STBC. System performance over a Rayleigh fading channel is investigated and the analysis is confirmed by simulation.

  7. Fracture of the humerus after cancellous bone graft harvesting in a dog.

    Science.gov (United States)

    Ferguson, J F

    1996-05-01

    A five-year-old male Shetland sheepdog underwent calcaneoquartal arthrodesis for instability of the proximal intertarsal joint. A cancellous bone graft was harvested from the proximal humerus and packed around the arthrodesis site. Twenty-four hours postoperatively the dog developed a non-weightbearing forelimb lameness. Clinical and radiographic examination revealed a fracture of the humerus through the hole used to obtain the graft. Surgical repair of the fracture led to an uneventful recovery.

  8. Cancellation of Collisional Frequency Shifts in Optical Lattice Clocks with Rabi Spectroscopy

    OpenAIRE

    Lee, Sangkyung; Park, Chang Yong; Lee, Won-Kyu; Yu, Dai-Hyuk

    2015-01-01

    We analyze both the s- and p-wave collision induced frequency shifts and propose a over-$\\pi$ pulse scheme to cancel the shifts in optical lattice clocks interrogated by a Rabi pulse. The collisional frequency shifts are analytically solved as a function of the pulse area and the inhomogeneity of the Rabi frequencies. Experimentally measured collisional frequency shifts in an Yb optical lattice clock are in good agreement with the analytical calculations. Based on our analysis, the over-$\\pi$...

  9. Coupling constants and brane tensions from anomaly cancellation in M-theory

    DEFF Research Database (Denmark)

    Harmark, Troels

    1998-01-01

    quantization that the brane tensions only have their standard form in the "downstairs" units. We consider the gauge variation of the classical theory and find that it cannot be gauge invariant, contrary to a recent claim. Finally we consider anomaly cancellation in the "downstairs" and "upstairs" approaches...... and obtain the values of λ6/κ4 and the two-and five-brane tensions....

  10. Distortion cancellation performance of miniature delay filters for feed-forward linear power amplifiers.

    Science.gov (United States)

    Roy, Manas K

    2002-11-01

    The technique of feed-forward amplitude control has been widely used in the linearization of power amplifiers for wireless communication systems. In this technique, an error signal due to third order intermodulation distortion (IMD) is extracted, amplified, and used to correct the delayed main line distorted signal. For example, a miniature prototype base station for the Global System for Mobile Communications/Code Division Multiple Access (GSM/CDMA) cellular system uses feed-forward amplifiers with bulky and expensive coaxial cables, about 20 feet in length, to provide about 25 ns of delay. This paper shows alternate space-saving approaches of achieving these delays using three different types of delay filters: electromagnetic interdigital/lumped (<2.5"), ceramic (<1.8"), and ladder-type surface acoustic wave (SAW) (0.15"). The delay lines introduce phase and amplitude imbalance and delay mismatch in the linearization loop due to fabrication tolerances. These adversely affect the IMD cancellation. Using an RF system simulation tool, this paper critically compares the IMD cancellation performance achieved using the three technologies. Simulation results show that the optimization of delay mismatch can achieve the desired cancellation more easily than other parameters. It is shown that, if the critical system parameter (phase deviation from linearity), is maintained at <2.5 degrees peak-to-peak over a 20 MHz bandwidth in the frequency range 855 MHz to 875 MHz, one can achieve 25 dB of IMD cancellation performance. This paper concludes with the suggestion of a set of realistic specifications for a miniature delay filter for the low power loop of the feed-forward amplifier.

  11. Effects of gas produced by degradation of Mg–Zn–Zr Alloy on cancellous bone tissue

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jingbo; Jiang, Hongfeng [Tianjin Hospital, 300211 Tianjin (China); Bi, Yanze; Sun, Jin e; Chen, Minfang; Liu, Debao [School of Materials Science and Engineering, Tianjin University of Technology, 300384 Tianjin (China)

    2015-10-01

    Mg–Zn–Zr alloy cylinders were implanted into the femoral condyles of Japanese big-ear white rabbits. X-ray showed that by 12 weeks following implantation the implant became obscure, around which the low-density area appeared and enlarged. By 24 weeks, the implant was more obscure and the density of the surrounding cancellous bone increased. Scanning electron microscopy examination showed bone tissue on the surface of the alloy attached by living fibers at 12 weeks. Micro-CT confirmed that new bone tissue on the surface of the residual alloy implant increased from 12 weeks to 24 weeks. By 12 weeks, many cavities in the cancellous bone tissue around the implant were noted with a CT value, similar to gas value, and increasing by 24 weeks (P < 0.01). Histological examination of hard tissue slices showed that bone tissue was visibly attached to the alloy in the femoral condyle at 12 weeks. The trabecular bone tissues became more intact and dense, and the cavities were filled with soft tissue at 24 weeks. In general, gas produced by the degradation of the Mg–Zn–Zr alloy can cause cavitation within cancellous bone, which does not affect osteogenesis of Mg alloy. - Highlights: • The degradation of Mg alloy in cancellous bone causes cavitation around the alloy. • At first, the CT value of the cavities is similar to the gas value. • The area of the cavities enlarges gradually by 12 weeks. • The cavities are filled with bone tissue and soft tissue gradually.

  12. Design and implementation of efficient low complexity biomedical artifact canceller for nano devices

    Directory of Open Access Journals (Sweden)

    Md Zia Ur RAHMAN

    2016-07-01

    Full Text Available In the current day scenario, with the rapid development of communication technology remote health care monitoring becomes as an intense research area. In remote health care monitoring, the primary aim is to facilitate the doctor with high resolution biomedical data. In order to cancel various artifacts in clinical environment in this paper we propose some efficient adaptive noise cancellation techniques. To obtain low computational complexity we combine clipping the data or error with Least Mean Square (LMS algorithm. This results sign regressor LMS (SRLMS, sign LMS (SLMS and sign LMS (SSLMS algorithms. Using these algorithms, we design Very-large-scale integration (VLSI architectures of various Biomedical Noise Cancellers (BNCs. In addition, the filtering capabilities of the proposed implementations are measured using real biomedical signals. Among the various BNCs tested, SRLMS based BNC is found to be better with reference to convergence speed, filtering capability and computational complexity. The main advantage of this technique is it needs only one multiplication to compute next weight. In this manner SRLMS based BNC is independent of filter length with reference to its computations. Whereas, the average signal to noise ratio achieved in the noise cancellation experiments are recorded as 7.1059dBs, 7.1776dBs, 6.2795dBs and 5.8847dBs for various BNCs based on LMS, SRLMS, SLMS and SSSLMS algorithms respectively. Based on the filtering characteristics, convergence and computational complexity, the proposed SRLMS based BNC architecture is well suited for nanotechnology applications.

  13. Efficient reference-free adaptive artifact cancellers for impedance cardiography based remote health care monitoring systems.

    Science.gov (United States)

    Mallam, Madhavi; Rao, K Chandra Bhutan

    2016-01-01

    In this paper, a new model for adaptive artifact cancelation in impedance cardiography (ICG) signals is presented. It is a hybrid model based on wavelet decomposition and an adaptive filter. A novel feature of this model is the implementation of reference-free adaptive artifact cancellers (AAC). For this implementation, the reference signal is constructed using a wavelet transformation. During critical conditions the filter weights may be negative and cause an imbalance in the convergence. To overcome this problem, we introduce non-negative adaptive algorithms in the proposed artifact canceller. To accelerate the performance of the AAC, we propose exponential non-negative and normalized non-negative algorithms to update the filter coefficients. The computational complexity of the filtering section in a remote health care system is important to avoid inter-symbol interference of the incoming samples. This can be achieved by combining sign-based algorithms with the adaptive filtering section. Finally, several AACs are developed using variants of the non-negative algorithms and performance measures are computed and compared. All of the proposed AACs are tested on actual ICG signals. Among the AACs evaluated, sign regressor normalized non-negative LMS (SRN(3)LMS) based adaptive artifact canceller achieves highest signal to noise ratio (SNR). The SNR achieved by this algorithm in baseline wander artifact elimination is 8.5312 dBs, in electrode muscle artifact elimination is 7.5908 dBs and in impedance measurement artifact elimination is 8.4231 dBs.

  14. Microdamage Caused by Fatigue Loading in Human Cancellous Bone: Relationship to Reductions in Bone Biomechanical Performance

    Science.gov (United States)

    Lambers, Floor M.; Bouman, Amanda R.; Rimnac, Clare M.; Hernandez, Christopher J.

    2013-01-01

    Vertebral fractures associated with osteoporosis are often the result of tissue damage accumulated over time. Microscopic tissue damage (microdamage) generated in vivo is believed to be a mechanically relevant aspect of bone quality that may contribute to fracture risk. Although the presence of microdamage in bone tissue has been documented, the relationship between loading, microdamage accumulation and mechanical failure is not well understood. The aim of the current study was to determine how microdamage accumulates in human vertebral cancellous bone subjected to cyclic fatigue loading. Cancellous bone cores (n = 32) from the third lumbar vertebra of 16 donors (10 male, 6 female, age 76±8.8, mean ± SD) were subjected to compressive cyclic loading at σ/E0 = 0.0035 (where σ is stress and E0 is the initial Young’s modulus). Cyclic loading was suspended before failure at one of seven different amounts of loading and specimens were stained for microdamage using lead uranyl acetate. Damage volume fraction (DV/BV) varied from 0.8±0.5% (no loading) to 3.4±2.1% (fatigue-loaded to complete failure) and was linearly related to the reductions in Young’s modulus caused by fatigue loading (r2 = 0.60, pfatigue life was nonlinear and suggests that most microdamage generation occurs late in fatigue loading, during the tertiary phase. Our results indicate that human vertebral cancellous bone tissue with a DV/BV of 1.5% is expected to have, on average, a Young’s modulus 31% lower than the same tissue without microdamage and is able to withstand 92% fewer cycles before failure than the same tissue without microdamage. Hence, even small amounts of microscopic tissue damage in human vertebral cancellous bone may have large effects on subsequent biomechanical performance. PMID:24386247

  15. A cost effective harmonic cancellation method for high frequency Silicon Carbide MOSFET based single phase inverter

    OpenAIRE

    Harrasi, A; Zobaa, AF

    2016-01-01

    This paper introduces a combinational modulation method to be used in classic full-bridge single phase inverters. The proposed method eliminates even-order harmonics at PWM stage in control section unlike the conventional method of even order harmonic cancelation in power stage and offers a cost effective design by switching one leg at high frequency. Using a low cost Digital Signal Controller (DSC) platform, regular sampling technique based on real time calculation was employed to verify the...

  16. Defense Contracting: Complete Historical Data Not Available on Canceled DOD Solicitations

    Science.gov (United States)

    2016-06-29

    federal executive agencies seek competition for contracting opportunities by issuing solicitations. In certain instances, after notifying industry of its...Department of Defense (DOD) canceled after receiving bids or proposals from industry between fiscal years 2010 and 2014.1 This report describes: 1...systems and interviewed officials from the office of the Under Secretary of Defense for Acquisition, Technology and Logistics . To identify examples of

  17. Oreopithecus was a bipedal ape after all: Evidence from the iliac cancellous architecture

    Science.gov (United States)

    Rook, Lorenzo; Bondioli, Luca; Köhler, Meike; Moyà-Solà, Salvador; Macchiarelli, Roberto

    1999-01-01

    Textural properties and functional morphology of the hip bone cancellous network of Oreopithecus bambolii, a 9- to 7-million-year-old Late Miocene hominoid from Italy, provide insights into the postural and locomotor behavior of this fossil ape. Digital image processing of calibrated hip bone radiographs reveals the occurrence of trabecular features, which, in humans and fossil hominids, are related to vertical support of the body weight, i.e., to bipedality. PMID:10411955

  18. [Is obesity a risk factor for complications, hospital admissions, and surgical cancellations in ambulatory surgery?].

    Science.gov (United States)

    Arance García, M; Docobo Durántez, F; Conde Guzmán, C; Pérez Torres, M C; Martín-Gil Parra, R; Fernández Jiménez, P E

    2015-03-01

    To determine the incidence of outcomes, unanticipated admissions and cancellations in patients operated in an Ambulatory surgery unit, and to establish the relationships with their body mass index (BMI). An observational descriptive prospective study was conducted in the Ambulatory surgery unit of the University Hospital Virgen del Rocío of Seville, on ASA I or II adult patients proposed for day case surgery with loco-regional or general anesthesia. A cohort of 1,088 patients was classified according to their body mass index into four groups: no obesity (BMI<30), obesity i (BMI 30-34.9), obesity ii (BMI 35-39.9), and morbid obesity iii (BMI 40-49.9). Postoperative outcomes (48h), inpatient admissions, and cancellations where calculated. The obesity ii (BMI 35-39.9) group showed a higher incidence of postoperative complications (7.69%), unplanned admissions (7.69%), and surgical cancellations (4.87%), doubling, at least, the incidence of adverse events of the other study groups, even when no significant difference was found. Outcomes where similar in all study groups. The results of this study suggest that moderate and severe obesity should be a risk factor for postoperative complications, unplanned admissions, and cancellations in outpatient surgery. Adequate patient selection and preoperative evaluation, as well as strategies for the prevention and control of the most frequents complications in obese patients are the key factors for their integration in major ambulatory surgery programs. Copyright © 2013 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.

  19. Conceptual design and software simulation of a wideband leakage cancellation circuit

    OpenAIRE

    Ang, Teo Hong

    2010-01-01

    Approved for public release; distribution is unlimited The objective of this thesis is to investigate a Wideband Leakage Cancellation Circuit (WLCC) to facilitate potential improvement of range resolution in single antenna Frequency Modulated Continuous Wave (FMCW) radar, as well as other applications. The research has successfully extended the operating bandwidth of a basic single frequency LCC by the use of a Frequency Demultiplexing and Multiplexing Circuit (FDMC) consisting of a bank o...

  20. Analysis of Adaptive Interference Cancellation Using Common-Mode Information in Wireline Communications

    Directory of Open Access Journals (Sweden)

    Per Ola Börjesson

    2007-01-01

    Full Text Available Joint processing of common-mode (CM and differential-mode (DM signals in wireline transmission can yield significant improvements in terms of throughput compared to using only the DM signal. Recent work proposed the employment of an adaptive CM-reference-based interference canceller and reported performance improvements based on simulation results. This paper presents a thorough investigation of the cancellation approach. A subchannel model of the CM-aided wireline channel is presented and the Wiener solutions for different adaptation strategies are derived. It is shown that a canceller, whose coefficients are adapted while the far-end transmitter is silent, yields a signal-to-noise power ratio (SNR that is higher than the SNR at the DM channel output for a large class of practically relevant cases. Adaptation while the useful far-end signal is present yields a front-end whose output SNR is considerably lower compared to the SNR of the DM channel output. The results are illustrated by simulations based on channel measurement data.

  1. Effect of Real-Time Feedback on Screw Placement Into Synthetic Cancellous Bone.

    Science.gov (United States)

    Gustafson, Peter A; Geeslin, Andrew G; Prior, David M; Chess, Joseph L

    2016-08-01

    The objective of this study is to evaluate whether real-time torque feedback may reduce the occurrence of stripping when inserting nonlocking screws through fracture plates into synthetic cancellous bone. Five attending orthopaedic surgeons and 5 senior level orthopaedic residents inserted 8 screws in each phase. In phase I, screws were inserted without feedback simulating conventional techniques. In phase II, screws were driven with visual torque feedback. In phase III, screws were again inserted with conventional techniques. Comparison of these 3 phases with respect to screw insertion torque, surgeon rank, and perception of stripping was used to establish the effects of feedback. Seventy-three of 239 screws resulted in stripping. During the first phase, no feedback was provided and the overall strip rate was 41.8%; this decreased to 15% with visual feedback (P perception of tactile sensation. This is significantly improved with utilization of real-time visual feedback of a torque versus roll curve. This concept of real-time feedback seems beneficial toward performance in synthetic cancellous bone and may lead to improved fixation in cancellous bone in a surgical setting.

  2. A Review on Successive Interference Cancellation-Based Optical PPM-CDMA Signaling

    Science.gov (United States)

    Alsowaidi, Naif; Eltaif, Tawfig; Mokhtar, Mohd Ridzuan

    2017-06-01

    This paper presents a comprehensive review of successive interference cancellation (SIC) scheme using pulse position modulation (PPM) for optical code division multiple access (OCDMA) systems. SIC scheme focuses on high-intensity signal, which will be selected after all users were detected, and then it will be subtracted from the overall received signal, hence, generating a new received signal. This process continues till all users eliminated one by one have been detected. It is shown that the random location of the sequences due to PPM encoding can reduce the probability of concentrated buildup of the pulse overlap in any one-slot time, and support SIC to easily remove the effect of the strongest signal at each stage of the cancellation process. The system bit error rate (BER) performance with modified quadratic congruence (MQC) codes used as signature sequence has been investigated. A detailed theoretical analysis of proposed system taking into account the impact of imperfect interference cancellation, the loss produced from the splitting during encoding and decoding, the channel loss and multiple access interference is presented. Results show that under average effective power constraint optical CDMA system using SIC scheme with M-ary PPM modulation outperforms conventional correlator detector and SIC scheme with on-off keying (OOK) modulation.

  3. Fully integrated low-noise readout circuit with automatic offset cancellation loop for capacitive microsensors.

    Science.gov (United States)

    Song, Haryong; Park, Yunjong; Kim, Hyungseup; Cho, Dong-Il Dan; Ko, Hyoungho

    2015-10-14

    Capacitive sensing schemes are widely used for various microsensors; however, such microsensors suffer from severe parasitic capacitance problems. This paper presents a fully integrated low-noise readout circuit with automatic offset cancellation loop (AOCL) for capacitive microsensors. The output offsets of the capacitive sensing chain due to the parasitic capacitances and process variations are automatically removed using AOCL. The AOCL generates electrically equivalent offset capacitance and enables charge-domain fine calibration using a 10-bit R-2R digital-to-analog converter, charge-transfer switches, and a charge-storing capacitor. The AOCL cancels the unwanted offset by binary-search algorithm based on 10-bit successive approximation register (SAR) logic. The chip is implemented using 0.18 μm complementary metal-oxide-semiconductor (CMOS) process with an active area of 1.76 mm². The power consumption is 220 μW with 3.3 V supply. The input parasitic capacitances within the range of -250 fF to 250 fF can be cancelled out automatically, and the required calibration time is lower than 10 ms.

  4. Fully Integrated Low-Noise Readout Circuit with Automatic Offset Cancellation Loop for Capacitive Microsensors

    Directory of Open Access Journals (Sweden)

    Haryong Song

    2015-10-01

    Full Text Available Capacitive sensing schemes are widely used for various microsensors; however, such microsensors suffer from severe parasitic capacitance problems. This paper presents a fully integrated low-noise readout circuit with automatic offset cancellation loop (AOCL for capacitive microsensors. The output offsets of the capacitive sensing chain due to the parasitic capacitances and process variations are automatically removed using AOCL. The AOCL generates electrically equivalent offset capacitance and enables charge-domain fine calibration using a 10-bit R-2R digital-to-analog converter, charge-transfer switches, and a charge-storing capacitor. The AOCL cancels the unwanted offset by binary-search algorithm based on 10-bit successive approximation register (SAR logic. The chip is implemented using 0.18 μm complementary metal-oxide-semiconductor (CMOS process with an active area of 1.76 mm2. The power consumption is 220 μW with 3.3 V supply. The input parasitic capacitances within the range of −250 fF to 250 fF can be cancelled out automatically, and the required calibration time is lower than 10 ms.

  5. Frame-Based Random Access with Interference Cancellation across Frames for Massive Machine Type Communications

    Directory of Open Access Journals (Sweden)

    Minjoong Rim

    2017-01-01

    Full Text Available One of the main requirements for next generation mobile or wireless communication systems is to effectively support a large number of machine type communication devices for Internet of things applications. In order to improve the random access capability in frame-based slotted Aloha environments, coded random access techniques have been proposed, in which multiple copies of a packet are transmitted per frame and the copies are cancelled out from the received signal if any single copy is successfully received. They, however, may increase the transmission power by sending multiple copies per frame. Above all, for systems with a small number of slots per frame, they may not be able to improve the performance by readily reaching a congested state. This paper proposes a new frame-based random access scheme, which sends at most one copy of a packet per frame but uses interference cancellation to improve the performance. If a successfully received packet is a retransmitted one, the previously transmitted signals for the packet can be cancelled out from the received signals for trying to decode other received packets. The proposed scheme has different characteristics than coded random access schemes and can be also combined with them to further improve the performance.

  6. Fast characterization of two ultrasound longitudinal waves in cancellous bone using an adaptive beamforming technique.

    Science.gov (United States)

    Taki, Hirofumi; Nagatani, Yoshiki; Matsukawa, Mami; Mizuno, Katsunori; Sato, Toru

    2015-04-01

    The received signal in through-transmission ultrasound measurements of cancellous bone consists of two longitudinal waves, called the fast and slow waves. Analysis of these fast and slow waves may reveal characteristics of the cancellous bone that would be good indicators of osteoporosis. Because the two waves often overlap, decomposition of the received signal is an important problem in the characterization of bone quality. This study proposes a fast and accurate decomposition method based on the frequency domain interferometry imaging method with a modified wave transfer function that uses a phase rotation parameter. The proposed method accurately characterized the fast and slow waves in the experimental study, and the residual intensity, which was normalized with respect to the received signal intensity, was less than -20 dB over the bone specimen thickness range from 6 to 15 mm. In the simulation study, the residual intensity was less than -20 dB over the specimen thickness range from 3 to 8 mm. Decomposition of a single received signal takes only 5 s using a laptop personal computer with a single central processing unit. The proposed method has great potential to provide accurate and rapid measurements of indicators of osteoporosis in cancellous bone.

  7. Efficient multichannel acoustic echo cancellation using constrained tap selection schemes in the subband domain

    Science.gov (United States)

    Desiraju, Naveen Kumar; Doclo, Simon; Wolff, Tobias

    2017-12-01

    Acoustic echo cancellation (AEC) is a key speech enhancement technology in speech communication and voice-enabled devices. AEC systems employ adaptive filters to estimate the acoustic echo paths between the loudspeakers and the microphone(s). In applications involving surround sound, the computational complexity of an AEC system may become demanding due to the multiple loudspeaker channels and the necessity of using long filters in reverberant environments. In order to reduce the computational complexity, the approach of partially updating the AEC filters is considered in this paper. In particular, we investigate tap selection schemes which exploit the sparsity present in the loudspeaker channels for partially updating subband AEC filters. The potential for exploiting signal sparsity across three dimensions, namely time, frequency, and channels, is analyzed. A thorough analysis of different state-of-the-art tap selection schemes is performed and insights about their limitations are gained. A novel tap selection scheme is proposed which overcomes these limitations by exploiting signal sparsity while not ignoring any filters for update in the different subbands and channels. Extensive simulation results using both artificial as well as real-world multichannel signals show that the proposed tap selection scheme outperforms state-of-the-art tap selection schemes in terms of echo cancellation performance. In addition, it yields almost identical echo cancellation performance as compared to updating all filter taps at a significantly reduced computational cost.

  8. Hardware Implementation of LMS-Based Adaptive Noise Cancellation Core with Low Resource Utilization

    Directory of Open Access Journals (Sweden)

    Omid Sharifi Tehrani

    2011-10-01

    Full Text Available A hardware implementation of adaptive noise cancellation (ANC core is proposed. Adaptive filters are widely used in different applications such as adaptive noise cancellation, prediction, equalization, inverse modeling and system identification. FIR adaptive filters are mostly used because of their low computation costs and their linear phase. Least mean squared algorithm (LMS is used to train FIR adaptive filter weights. Advances in semiconductor technology especially in digital signal processors (DSP and field programmable gate arrays (FPGA with hundreds of mega hertz in speed, will allow digital designers to embed essential digital signal processing units in small chips. But designing a synthesizable core on an FPGA is not always as simple as DSP chips due to complexity and limitations of FPGAs. In this paper we design anLMS-based FIR adaptive filter for adaptive noise cancellation based on VHDL97 hardware description language (HDL and Xilinx SPARTAN3E (XC3S500E which utilizes low resources and is high performance and FPGA-brand independent so can be implemented on different FPGA brands (Xilinx, ALTERA, ACTEL. Simulations are done in MODELSIM and MATLAB and implementation is done with Xilinx ISE. Finally, result are compared with other papers for better judgment.

  9. Gradient Based Adaptive Algorithm for Echo Cancellation from Recorded Echo Corrupted Speech

    Directory of Open Access Journals (Sweden)

    Upal Mahbub

    2014-01-01

    Full Text Available An offline single channel acoustic echo cancellation (AEC scheme is proposed based on gradient based adaptive least mean squares (LMS algorithm considering a major practical application of echo cancellation system for enhancing recorded echo corrupted speech data. The unavailability of a reference signal makes the problem of single channel adaptive echo cancellation to be extremely difficult to handle. Moreover, continuous feedback of the echo corrupted signal to the input microphone can significantly degrade the quality of the original speech signal and may even result in howling. In order to overcome these problems, in the proposed scheme, the delayed version of the echo corrupted speech signal is considered as a reference. An objective function is thus formulated and thereby a modified LMS update equation is derived, which is shown to converge to the optimum Wiener-Hopf solution. The performance of the proposed method is evaluated in terms of both subjective and objective measures via extensive experimentation on several real-life echo corrupted signals and very satisfactory performance is obtained.

  10. Shot-noise-limited optical Faraday polarimetry with enhanced laser noise cancelling

    Science.gov (United States)

    Li, Jiaming; Luo, Le; Carvell, Jeff; Cheng, Ruihua; Lai, Tianshu; Wang, Zixin

    2014-03-01

    We present a shot-noise-limited measurement of optical Faraday rotations with sub-ten-nanoradian angular sensitivity. This extremely high sensitivity is achieved by using electronic laser noise cancelling and phase sensitive detection. Specially, an electronic laser noise canceller with a common mode rejection ratio of over 100 dB was designed and built for enhanced laser noise cancelling. By measuring the Faraday rotation of ambient air, we demonstrate an angular sensitivity of up to 9.0×10-9 rad/√Hz , which is limited only by the shot-noise of the photocurrent of the detector. To date, this is the highest angular sensitivity ever reported for Faraday polarimeters in the absence of cavity enhancement. The measured Verdet constant of ambient air, 1.93(3)×10-9rad/(G cm) at 633 nm wavelength, agrees extremely well with the earlier experiments using high finesse optical cavities. Further, we demonstrate the applications of this sensitive technique in materials science by measuring the Faraday effect of an ultrathin iron film.

  11. Total-body irradiation of postpubertal mice with (137)Cs acutely compromises the microarchitecture of cancellous bone and increases osteoclasts.

    Science.gov (United States)

    Kondo, Hisataka; Searby, Nancy D; Mojarrab, Rose; Phillips, Jonathan; Alwood, Joshua; Yumoto, Kenji; Almeida, Eduardo A C; Limoli, Charles L; Globus, Ruth K

    2009-03-01

    Ionizing radiation can cause substantial tissue degeneration, which may threaten the long-term health of astronauts and radiotherapy patients. To determine whether a single dose of radiation acutely compromises structural integrity in the postpubertal skeleton, 18-week-old male mice were exposed to (137)Cs gamma radiation (1 or 2 Gy). The structure of high-turnover, cancellous bone was analyzed by microcomputed tomography (microCT) 3 or 10 days after irradiation and in basal controls (tissues harvested at the time of irradiation) and age-matched controls. Irradiation (2 Gy) caused a 20% decline in tibial cancellous bone volume fraction (BV/TV) within 3 days and a 43% decline within 10 days, while 1 Gy caused a 28% reduction 10 days later. The BV/TV decrement was due to increased spacing and decreased thickness of trabeculae. Radiation also increased ( approximately 150%) cancellous surfaces lined with tartrate-resistant, acid phosphatase-positive osteoclasts, an index of increased bone resorption. Radiation decreased lumbar vertebral BV/TV 1 month after irradiation, showing the persistence of cancellous bone loss, although mechanical properties in compression were unaffected. In sum, a single dose of gamma radiation rapidly increased osteoclast surface in cancellous tissue and compromised cancellous microarchitecture in the remodeling appendicular and axial skeleton of postpubertal mice.

  12. Causes of elective surgery cancellation and theatre throughput efficiency in an Australian urology unit.

    Science.gov (United States)

    Keller, Andrew; Ashrafi, Akbar; Ali, Ahmad

    2014-01-01

    To evaluate our unit's theatre throughput efficiency, to identify where inefficiencies existed and consequently where the greatest improvement might be made.To identify the causes of day of surgery cancellations and how they might be avoided.  A prospective audit of theatre utilisation was undertaken over a 6 month period between 05/02//2013 and 02/08/2013 at Ipswich General Hospital, QLD, Australia.TIMES COLLECTED WERE: time of patient arrival in anaesthetic bay, start time of operative procedure, end time of operative procedure, and time of patient leaving theatre.The causative factors for any delays or day of surgery cancellations were identified and recorded where possible.  In the six month period 26,850 sessional minutes were available for elective operating over 100 operating sessions.304 elective cases were performed, split between 21 major and 283 minor proceduresThe sessions ran overtime a cumulative 2114 minutes.Total non-operative minutes totalled 13,209 (50.3% of all available time), split between late starts 499 minutes (1.8%), early list finishes 1894 minutes (7.05%),  changeover time 1869 minutes (6.9%) and anaesthetic time, 8974 minutes (33.4%)Actual operating time only compromised 50.7% of all available elective operating session time (13,614 minutes)Theatre utilisation was 91.8%.51 procedures were cancelled on the day of surgery during the audit period, representing 14.3% of all scheduled procedures.The most common reason for cancellation was lack of surgical fitness, followed by inadequate operative time.   A significant proportion of all elective operative time was consumed by non-operative minutes.Inefficiencies existed in turnover of patients as well as over as well as underbooking of patients on elective lists.An excessive number of cases were cancelled on the day of surgery, wasting valuable operative time.A multi-parametric approach must be taken to improve operation list utilisation.

  13. INTRACAPSULAR FRACTURE OF NECK OF FEMUR (IC#NF - OSTEOSYNTHESIS BY CANNULATED CANCELLOUS SCREW FIXATION

    Directory of Open Access Journals (Sweden)

    L. Lokanadha Rao

    2016-09-01

    Full Text Available Fractures of neck of femur have always presented great challenges to the orthopaedic surgeons. This remains, even today, an unsolved fracture as far as treatment and results are concerned. Results depend upon the extent of injury, timing of surgery and adequacy of reduction and fixation. Fixation with cannulated cancellous screws is usually adequate for femoral neck fractures. Lateral cortex plays a very important role in screw fixation. AIMS AND OBJECTIVES To study the effectiveness of cannulated cancellous screw fixation for treatment of fracture of neck of femur in adults. MATERIALS AND METHODS This study was conducted at Andhra Medical College, King George Hospital, Visakhapatnam, AP from Nov 2013 to Oct 2015. The patients with intracapsular fracture of neck of femur are evaluated with pre-operative X-rays of pelvis with both hips and X-ray of the concerned hip joint both in anteroposterior and lateral views and their outcome was evaluated postoperatively after fixation with cancellous screws. The outcome is evaluated in terms of pain relief, extent of ambulation achieved after surgery. The classifications we followed are Pauwel’s and Garden’s classification of fracture of neck of femur. The patients were followed up to one year to assess the functional outcome. OBSERVATION AND RESULTS A good result was obtained in 66.1% of the patients, excellent in 23.2%, fair in 3.8% and poor result in 6.9% of the patients. Complications such as Non-union & avascular necrosis in one case, Non-union and Extrusion of screws in one case, Cut through of screws into articular surface leading to painful joint in one case. Most of the cases of intracapsular neck of femur were in the age group of 31-40 years. There was male preponderance as shown in this study (69%. CONCLUSION By the usage of multiple cannulated cancellous lag screws, compression effect at the fracture site is achieved, it also avoids re-displacement and rotations. The implant occupies less

  14. Kit (W-sh) Mutation Prevents Cancellous Bone Loss during Calcium Deprivation.

    Science.gov (United States)

    Lotinun, Sutada; Suwanwela, Jaijam; Poolthong, Suchit; Baron, Roland

    2017-10-14

    Calcium is essential for normal bone growth and development. Inadequate calcium intake increases the risk of osteoporosis and fractures. Kit ligand/c-Kit signaling plays an important role in regulating bone homeostasis. Mice with c-Kit mutations are osteopenic. The present study aimed to investigate whether impairment of or reduction in c-Kit signaling affects bone turnover during calcium deprivation. Three-week-old male WBB6F1/J-Kit (W) /Kit (W-v) /J (W/W (v) ) mice with c-Kit point mutation, Kit (W-sh) /HNihrJaeBsmJ (W (sh) /W (sh) ) mice with an inversion mutation in the regulatory elements upstream of the c-Kit promoter region, and their wild-type controls (WT) were fed either a normal (0.6% calcium) or a low calcium diet (0.02% calcium) for 3 weeks. μCT analysis indicated that both mutants fed normal calcium diet had significantly decreased cortical thickness and cancellous bone volume compared to WT. The low calcium diet resulted in a comparable reduction in cortical bone volume and cortical thickness in the W/W (v) and W (sh) /W (sh) mice, and their corresponding controls. As expected, the low calcium diet induced cancellous bone loss in the W/W (v) mice. In contrast, W (sh) /W (sh) cancellous bone did not respond to this diet. This c-Kit mutation prevented cancellous bone loss by antagonizing the low calcium diet-induced increase in osteoblast and osteoclast numbers in the W (sh) /W (sh) mice. Gene expression profiling showed that calcium deficiency increased Osx, Ocn, Alp, type I collagen, c-Fms, M-CSF, and RANKL/OPG mRNA expression in controls; however, the W (sh) mutation suppressed these effects. Our findings indicate that although calcium restriction increased bone turnover, leading to osteopenia, the decreased c-Kit expression levels in the W (sh) /W (sh) mice prevented the low calcium diet-induced increase in cancellous bone turnover and bone loss but not the cortical bone loss.

  15. On the applicability of bovine morsellized cortico-cancellous bone as a substitute for human morsellized cortico-cancellous bone for in vitro mechanical testing.

    Science.gov (United States)

    Lunde, Knut B; Foss, Olav A; Skallerud, Bjørn

    2008-12-05

    Morsellized cortico-cancellous bone (MCB) is frequently used in orthopaedic revision surgery to restore lost bone stock. In this study, we examine the validity of using bovine MCB as a substitute for human MCB in in vitro mechanical testing of bone grafts. The paper describes the fat and water content of impacted and unimpacted human and bovine MCB. During this work we applied constrained compression testing to describe the elastic, plastic and time dependent response. Nearly all parameters were found to be significantly different and were influenced differently by impaction for the two types of MCB. The denser trabecular structure, higher fat content of bovine MCB and higher stiffness and compressive strength of cortical bovine bone may explain the differences observed. Consequently we are not confident about the applicability of bovine MCB as a substitute for human MCB for in vitro mechanical testing.

  16. Calcium phosphate cement augmentation of cancellous bone screws can compensate for the absence of cortical fixation.

    Science.gov (United States)

    Stadelmann, Vincent A; Bretton, Elise; Terrier, Alexandre; Procter, Philip; Pioletti, Dominique P

    2010-11-16

    An obvious means to improve the fixation of a cancellous bone screw is to augment the surrounding bone with cement. Previous studies have shown that bone augmentation with Calcium Phosphate (CaP) cement significantly improves screw fixation. Nevertheless, quantitative data about the optimal distribution of CaP cement is not available. The present study aims to show the effect of cement distribution on the screw fixation strength for various cortical thicknesses and to determine the conditions at which cement augmentation can compensate for the absence of cortical fixation in osteoporotic bone. In this study, artificial bone materials were used to mimic osteoporotic cancellous bone and cortical bone of varying thickness. These bone constructs were used to test the fixation strength of cancellous bone screws in different cortical thicknesses and different cement augmentation depths. The cement distribution was measured with microCT. The maximum pullout force was measured experimentally. The microCT analysis revealed a pseudo-conic shape distribution of the cement around the screws. While the maximum pullout strength of the screws in the artificial bone only was 30±7N, it could increase up to approximately 1000N under optimal conditions. Cement augmentation significantly increased pullout force in all cases. The effect of cortical thickness on pullout force was reduced with increased cement augmentation depth. Indeed, cement augmentation without cortical fixation increased pullout forces over that of screws without cement augmentation but with cortical fixation. Since cement augmentation significantly increased pullout force in all cases, we conclude that the loss of cortical fixation can be compensated by cement augmentation. Copyright © 2010 Elsevier Ltd. All rights reserved.

  17. Systemic intermittent parathyroid hormone treatment improves osseointegration of press-fit inserted implants in cancellous bone.

    Science.gov (United States)

    Daugaard, Henrik; Elmengaard, Brian; Andreassen, Troels Torp; Lamberg, Anders; Bechtold, Joan Elisabeth; Soballe, Kjeld

    2012-08-01

    Intermittent administration of parathyroid hormone (PTH) has an anabolic effect on bone, as confirmed in human osteoporosis studies, distraction osteogenesis, and fracture healing. PTH in rat models leads to improved fixation of implants in low-density bone or screw insertion transcortically. We examined the effect of human PTH (1-34) on the cancellous osseointegration of unloaded implants inserted press-fit in intact bone of higher animal species. 20 dogs were randomized to treatment with human PTH (1-34), 5 μg/kg/day subcutaneously, or placebo for 4 weeks starting on the day after insertion of a cylindrical porous coated plasma-sprayed titanium alloy implant in the proximal metaphyseal cancellous bone of tibia. Osseointegration was evaluated by histomorphometry and fixation by push-out test to failure. Surface fraction of woven bone at the implant interface was statistically significantly higher in the PTH group by 1.4 fold with (median (interquartile range) 15% (13-18)) in the PTH group and 11% (7-13) in control. The fraction of lamellar bone was unaltered. No significant difference in bone or fibrous tissue was observed in the circumferential regions of 0-500, 500-1,000, and 1,000-2,000 μm around the implant. Mechanically, the implants treated with PTH showed no significant differences in total energy absorption, maximum shear stiffness, or maximum shear strength. Intermittent treatment with PTH (1-34) improved histological osseointegration of a prosthesis inserted press-fit at surgery in cancellous bone, with no additional improvement of the initial mechanical fixation at this time point.

  18. Benign paroxysmal positional vertigo after use of noise-canceling headphones.

    Science.gov (United States)

    Dan-Goor, Eric; Samra, Monica

    2012-01-01

    Benign paroxysmal positional vertigo (BPPV) is a common cause of vertigo. We describe a case of a woman presenting acutely with a severe episode of disabling positional vertigo. Although she had no known etiologic risk factors, this attack followed 12 hours of continuously wearing digital noise-canceling headphones. This is the first such reported association between BPPV and the use of this gadget. We also provide a short review of BPPV and speculate on the possible pathogenic mechanisms involved. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. Active power filters for harmonic cancellation in conventional and advanced aircraft electric power systems

    Energy Technology Data Exchange (ETDEWEB)

    Eid, A.; El-Mohandes, T. [South Valley University (Egypt); Abdel-Salam, M. [Electrical Engineering Department, Assiut University, Al-Gamaa street, Assiut 71518 (Egypt); El-Kishky, H. [University of Texas at Tyler (United States)

    2009-01-15

    Conventional and advanced civil aircraft electric power systems are simulated and controlled to be within standards regarding the voltage magnitude and frequency everywhere in the system at different loading scenarios. Harmonics in conventional and advanced aircraft power systems are calculated and reduced using a well-designed active power filter. The control circuit of the filter is based on the perfect harmonic cancellation method. The designed filter results in bringing the harmonics in both aircraft systems down to be within the standard limits of IEEE-519 and MIL-STD-704E. (author)

  20. A New Probe Noise Approach For Acoustic Feedback Cancellation In Hearing Aids

    DEFF Research Database (Denmark)

    Guo, Meng; Jensen, Søren Holdt; Jensen, Jesper

    Acoustic feedback is a big challenge in hearing aids. If not appropriately treated, the feedback limits the maximum possible amplification and may lead to significant sound distortions. In a state-of-the-art hearing aid, an acoustic feedback cancellation (AFC) system is used to compensate...... the artifacts caused by acoustic feedback. The AFC is usually carried out by adaptively estimating the feedback paths (from receiver to micro-phones) and using these estimates to reduce the artifacts introduced by the acoustic feedback. One major limitation in the widely used adaptive filter technique for AFC...

  1. Conventional, Bayesian, and Modified Prony's methods for characterizing fast and slow waves in equine cancellous bone

    OpenAIRE

    Groopman, Amber M.; Katz, Jonathan I.; Holland, Mark R.; Fujita, Fuminori; Matsukawa, Mami; Mizuno, Katsunori; Wear, Keith A.; Miller, James G.

    2015-01-01

    Conventional, Bayesian, and the modified least-squares Prony's plus curve-fitting (MLSP + CF) methods were applied to data acquired using 1 MHz center frequency, broadband transducers on a single equine cancellous bone specimen that was systematically shortened from 11.8 mm down to 0.5 mm for a total of 24 sample thicknesses. Due to overlapping fast and slow waves, conventional analysis methods were restricted to data from sample thicknesses ranging from 11.8 mm to 6.0 mm. In contrast, Bayesi...

  2. An Improved Algorithm of Successive Interference Cancellation for STC-OFDM Systems

    Directory of Open Access Journals (Sweden)

    Wei Shihong

    2014-03-01

    Full Text Available STC-OFDM systems effectively overcome the disadvantage of inter symbol interference and frequency selective fading for Orthogonal Frequency Division Multiplexing communication systems, however, there are still some issues, such as how to suppressing mutual interference due to multi-antenna transmitting. In this paper, an improving algorithm combining with channel frequency response recovery is proposed, which recover the channel frequency response of the pilot before successive interference cancellation and reduce the effects of the channel frequency response estimation. Theoretical analysis and computer simulation shows that the proposal algorithm can improve performance of Bit Error Rate and suppress the interference in the STC-OFDM communication systems.

  3. Novel Acoustic Feedback Cancellation Approaches In Hearing Aid Applications Using Probe Noise and Probe Noise Enhancement

    DEFF Research Database (Denmark)

    Guo, Meng; Jensen, Søren Holdt; Jensen, Jesper

    2012-01-01

    and annoying; this makes the traditional probe noise approach less useful in practical applications. In this work, we explain theoretically the decreased convergence rate when using low-level probe noise in the traditional approach, before we propose and study analytically two new probe noise approaches...... the proposed approaches much more attractive in practical applications. We demonstrate this through a simulation experiment with audio signals in a hearing aid acoustic feedback cancellation system, where the convergence rate is improved by as much as a factor of 10....

  4. Cancelling the Maxim of Quantity: Another challenge for a Gricean theory of Scalar Implicatures

    Directory of Open Access Journals (Sweden)

    Danny Fox

    2014-04-01

    Full Text Available Grice (1975 pointed out that the ignorance inferences normally drawn when disjunctive sentences are uttered are cancelled when it is presupposed that speakers are not going to provide all of the relevant information that they have available (e.g., in the context of a treasure hunt. This argues that ignorance inferences depend on the maxim of quantity for their derivation. Here it is argued that the situation with Scalar Implicatures is different. This is expected by the grammatical theory of Scalar Implicatures, but not by standard Gricean or neo-Gricean alternatives. http://dx.doi.org/10.3765/sp.7.5 BibTeX info

  5. Results of the Gallium-Clad Phase 3 and Phase 4 tasks (canceled prior to completion)

    Energy Technology Data Exchange (ETDEWEB)

    Morris, R.N.

    1998-08-01

    This report summarizes the results of the Gallium-Clad interactions Phase 3 and 4 tasks. Both tasks were to involve examining the out-of-pile stability of residual gallium in short fuel rods with an imposed thermal gradient. The thermal environment was to be created by an electrical heater in the center of the fuel rod and coolant flow on the rod outer cladding. Both tasks were canceled due to difficulties with fuel pellet fabrication, delays in the preparation of the test apparatus, and changes in the Fissile Materials Disposition program budget.

  6. Analysis of Adaptive Feedback and Echo Cancelation Algorithms in A General Multiple-Microphone and Single-Loudspeaker System

    DEFF Research Database (Denmark)

    Guo, Meng; Elmedyb, Thomas Bo; Jensen, Søren Holdt

    2011-01-01

    In this paper, we analyze a general multiple-microphone and single-loudspeaker system, where an adaptive algorithm is used to cancel acoustic feedback/echo and a beamformer processes the feedback/echo canceled signals. This system can be viewed as part of a typical hearing aid system and....../or a traditional acoustic echo cancelation system. We introduce and derive an approximation of a useful frequency domain measure - the power transfer function - and show how to predict the system stability bound, convergence rate and the steady-state behavior across time and frequency. Furthermore, we show how...... the derived expressions can be used to determine e.g. the step size parameter in the adaptive algorithms to achieve a desired system property e.g. convergence rate at a specific frequency....

  7. Force sensing based on coherent quantum noise cancellation in a hybrid optomechanical cavity with squeezed-vacuum injection

    Science.gov (United States)

    Motazedifard, Ali; Bemani, F.; Naderi, M. H.; Roknizadeh, R.; Vitali, D.

    2016-07-01

    We propose and analyse a feasible experimental scheme for a quantum force sensor based on the elimination of backaction noise through coherent quantum noise cancellation (CQNC) in a hybrid atom-cavity optomechanical setup assisted with squeezed vacuum injection. The force detector, which allows for a continuous, broadband detection of weak forces well below the standard quantum limit (SQL), is formed by a single optical cavity simultaneously coupled to a mechanical oscillator and to an ensemble of ultracold atoms. The latter acts as a negative-mass oscillator so that atomic noise exactly cancels the backaction noise from the mechanical oscillator due to destructive quantum interference. Squeezed vacuum injection enforces this cancellation and allows sub-SQL sensitivity to be reached in a very wide frequency band, and at much lower input laser powers.

  8. Planning serials cancellations and cooperative collection development in the health sciences: methodology and background information.

    Science.gov (United States)

    Bourne, C P

    1975-10-01

    In an era of steady-state budgets many research and academic libraries must cancel a significant number of current serials to maintain acquisitions of monographs. Thus paper reviews several techniques that have been used or that are of potential use in a rational selection of titles for cancellation. The context of the proposed methodology involves a network of libraries rather than an individual library. The methodology was tested with specific health sciences serial titles held by University of California libraries and resource libraries in NLM Region XI. As a test for the proposed methodology, background data were collected on 600 current foreign language serial titles included in SERLINE and held by at least one of the libraries in the networks of interest. Price, major secondary service coverage with productivity/impact factors, extent of holdings, and average number of recorded circulations per year in several of the libraries were recorded for each title. With the use of several different rules, estimates were made of the subscription savings that might be realized. It seems feasible to extend the same methodology to other groups of serial titles.

  9. A Particle Model for Prediction of Cement Infiltration of Cancellous Bone in Osteoporotic Bone Augmentation.

    Directory of Open Access Journals (Sweden)

    Ehsan Basafa

    Full Text Available Femoroplasty is a potential preventive treatment for osteoporotic hip fractures. It involves augmenting mechanical properties of the femur by injecting Polymethylmethacrylate (PMMA bone cement. To reduce the risks involved and maximize the outcome, however, the procedure needs to be carefully planned and executed. An important part of the planning system is predicting infiltration of cement into the porous medium of cancellous bone. We used the method of Smoothed Particle Hydrodynamics (SPH to model the flow of PMMA inside porous media. We modified the standard formulation of SPH to incorporate the extreme viscosities associated with bone cement. Darcy creeping flow of fluids through isotropic porous media was simulated and the results were compared with those reported in the literature. Further validation involved injecting PMMA cement inside porous foam blocks - osteoporotic cancellous bone surrogates - and simulating the injections using our proposed SPH model. Millimeter accuracy was obtained in comparing the simulated and actual cement shapes. Also, strong correlations were found between the simulated and the experimental data of spreading distance (R(2 = 0.86 and normalized pressure (R(2 = 0.90. Results suggest that the proposed model is suitable for use in an osteoporotic femoral augmentation planning framework.

  10. Suspensão de cirurgia de catarata e suas causas Reasons for cataract surgery cancelation

    Directory of Open Access Journals (Sweden)

    Rodrigo Pessoa Cavalcanti Lira

    2001-10-01

    Full Text Available Com o objetivo de verificar as causas de suspensão de cirurgia de catarata e sugerir medidas para melhorar a eficiência do serviço prestado à população, foi realizado um estudo transversal no serviço de oftalmologia de um hospital universitário do Estado de São Paulo. A amostra foi composta por 200 indivíduos. A média de idade foi de 68± 11,4 anos. As causas de suspensão de cirurgia foram: condição clínica desfavorável (23,1%; horário cirúrgico insuficiente (35,9%; e não comparecimento do paciente (41%. Os fatores causadores foram, majoritariamente, as razões sociais e o funcionamento do hospital.To study the reasons for canceling cataract surgeries, and to suggest actions to improve the efficiency of patient care. A cross-sectional study was carried out in a university hospital's ophthalmology clinic of the state of São Paulo, Brazil. Two hundred subjects were randomly selected. The mean age was 68± 11.4 years old. The reasons for canceling surgery were: unpropitious clinical condition (23.1%; tight schedule (35.9%; and patient non-attendance (41%. Most of the reasons related to social issues and the hospital's administrative aspects.

  11. Cancellation of elective surgery in an institution III level of care

    Directory of Open Access Journals (Sweden)

    Augusto Muñoz-Caicedo

    2011-09-01

    Full Text Available Objective: Identify the causes that influence the cancella­tion of elective surgery at a III level of complexity of the city of Popayan in 2010. Methods: We performed a descriptive, cross-sectional in a population of 1007 patients surgically scheduled between February and April 2010, of which 133 were suspended elective surgery, was electively. We used diary that takes in the surgery department, dealing with monthly systematically and instruments developed accor­ding to current regulatory framework. The data analysis was performed using SPSS-15. Results: canceled: 13.2% of surgeries that were scheduled were the most frequent causes of patient contraindications by 36,1%, followed by extension of the previous surgery in 11,3% and in the same percentage of patient non-attendance. Conclusion: The cancellation of surgeries in the unit under investigation was due to poten­tially preventable causes, reflecting an economic impact on the perception of resources by the institution, which involves there organization of services with process standardization.

  12. Secure amplify-and-forward untrusted relaying networks using cooperative jamming and zero-forcing cancelation

    KAUST Repository

    Park, Kihong

    2015-12-03

    In this paper, we investigate secure transmission in untrusted amplify-and-forward half-duplex relaying networks with the help of cooperative jamming at the destination (CJD). Under the assumption of full channel state information (CSI), conventional CJD using self-interference cancelation at the destination is efficient when the untrusted relay has no capability to suppress the jamming signal. However, if the source and destination are equipped with a single antenna and the only untrusted relay is equipped with N multiple antennas, it can remove the jamming signal from the received signal by linear filters and the full multiplexing gain of relaying cannot be achievable with the conventional CJD due to the saturation of the secrecy rate at the high transmit power regime. We propose in this paper new CJD scheme where neither destination nor relay can acquire CSI of relay-destination link. Our proposed scheme utilizes zero-forcing cancelation based on known jamming signals instead of self-interference subtraction, while the untrusted relay cannot suppress the jamming signals due to the lack of CSI. We show that the secrecy rate of the proposed scheme can enjoy a half of multiplexing gain in half-duplex relaying while that of conventional CJD is saturated at high transmit power for N ???2. The impact of channel estimation error at the destination is also investigated to show the robustness of the proposed scheme against strong estimation errors.

  13. Optimized demineralization of human cancellous bone by application of a vacuum.

    Science.gov (United States)

    Eagle, Mark J; Rooney, Paul; Kearney, John N

    2015-07-01

    Human demineralized bone matrix derived from cortical bone is used by surgeons due to its ability to promote bone formation. There is also a need for shaped demineralized bone matrices made from cancellous bone, where the properties of the material allow its insertion into defects, therefore acting as a void filler and scaffold onto which new bone can form. In this study, we report that demineralized bone sponges were prepared by dissecting and cutting knee bone into cancellous bone cubes of 1 cm(3) . These cubes were then taken through a series of warm water washes, some with sonication, centrifugation, and two decontamination chemical washes. The cubes were optimally demineralized into sponges with 0.5N hydrochloric acid under vacuum with constant pH measurement. Demineralization was confirmed by quantitative measurement of calcium and qualitatively by compression. The sponges were freeze dried before terminal sterilisation with a target dose of 25 kGy gamma radiation whilst frozen. Samples of the sponges were histologically examined for calcium and collagen and also tested for osteoinductivity. Data showed well defined collagen staining in the sponges, with little residual calcium. Sponges from two out of three donors demonstrated osteoinductivity when implanted into the muscle of an athymic mouse. © 2014 Wiley Periodicals, Inc.

  14. Insurance cancellations in context: stability of coverage in the nongroup market prior to health reform.

    Science.gov (United States)

    Sommers, Benjamin D

    2014-05-01

    Recent cancellations of nongroup health insurance plans generated much policy debate and raised concerns that the Affordable Care Act (ACA) may increase the number of uninsured Americans in the short term. This article provides evidence on the stability of nongroup coverage using US census data for the period 2008-11, before ACA provisions took effect. The principal findings are threefold. First, this market was characterized by high turnover: Only 42 percent of people with nongroup coverage at the outset of the study period retained that coverage after twelve months. Second, 80 percent of people experiencing coverage changes acquired other insurance within a year, most commonly from an employer. Third, turnover varied across groups, with stable coverage more common for whites and self-employed people than for other groups. Turnover was particularly high among adults ages 19-35, with only 21 percent of young adults retaining continuous nongroup coverage for two years. Given estimates from 2012 that 10.8 million people were covered in this market, these results suggest that 6.2 million people leave nongroup coverage annually. This suggests that the nongroup market was characterized by frequent disruptions in coverage before the ACA and that the effects of the recent cancellations are not necessarily out of the norm. These results can serve as a useful pre-ACA baseline with which to evaluate the law's long-term impact on the stability of nongroup coverage.

  15. Nonlinear modelling of polymer electrolyte membrane fuel cell stack using nonlinear cancellation technique

    Science.gov (United States)

    Barus, R. P. P.; Tjokronegoro, H. A.; Leksono, E.; Ismunandar

    2014-09-01

    Fuel cells are promising new energy conversion devices that are friendly to the environment. A set of control systems are required in order to operate a fuel cell based power plant system optimally. For the purpose of control system design, an accurate fuel cell stack model in describing the dynamics of the real system is needed. Currently, linear model are widely used for fuel cell stack control purposes, but it has limitations in narrow operation range. While nonlinear models lead to nonlinear control implemnetation whos more complex and hard computing. In this research, nonlinear cancellation technique will be used to transform a nonlinear model into a linear form while maintaining the nonlinear characteristics. The transformation is done by replacing the input of the original model by a certain virtual input that has nonlinear relationship with the original input. Then the equality of the two models is tested by running a series of simulation. Input variation of H2, O2 and H2O as well as disturbance input I (current load) are studied by simulation. The error of comparison between the proposed model and the original nonlinear model are less than 1 %. Thus we can conclude that nonlinear cancellation technique can be used to represent fuel cell nonlinear model in a simple linear form while maintaining the nonlinear characteristics and therefore retain the wide operation range.

  16. Real-time adaptive concepts in acoustics blind signal separation and multichannel echo cancellation

    CERN Document Server

    Schobben, Daniel W E

    2001-01-01

    Blind Signal Separation (BSS) deals with recovering (filtered versions of) source signals from an observed mixture thereof. The term `blind' relates to the fact that there are no reference signals for the source signals and also that the mixing system is unknown. This book presents a new method for blind signal separation, which is developed to work on microphone signals. Acoustic Echo Cancellation (AEC) is a well-known technique to suppress the echo that a microphone picks up from a loudspeaker in the same room. Such acoustic feedback occurs for example in hands-free telephony and can lead to a perceived loud tone. For an application such as a voice-controlled television, a stereo AEC is required to suppress the contribution of the stereo loudspeaker setup. A generalized AEC is presented that is suited for multi-channel operation. New algorithms for Blind Signal Separation and multi-channel Acoustic Echo Cancellation are presented. A background is given in array signal processing methods, adaptive filter the...

  17. Propagation of two longitudinal waves in human cancellous bone: an in vitro study.

    Science.gov (United States)

    Mizuno, Katsunori; Matsukawa, Mami; Otani, Takahiko; Laugier, Pascal; Padilla, Frédéric

    2009-05-01

    The ultrasonic wave propagation of fast and slow waves was investigated in vitro in 35 cubic cancellous bone specimens extracted from human femoral heads. Measurements were performed in three orthogonal directions using home-made PVDF transducers excited by a single sinusoidal wave at 1 MHz. The apparent density of the specimens was measured. Two separated fast and slow waves were clearly observed in 16 specimens, mainly in the main load direction. The waveforms and the sound speeds of fast and slow waves were similar to the reported data in bovine bone. The group of specimens in which the two waves were observed did not exhibit statistically higher apparent density than the rest of the specimens, but did exhibit statistically higher acoustic anisotropy ratio. The speeds in the main load direction were higher than those in the other direction. The fast and slow wave speeds were in good agreement with Biot's model, showing an increase with bone volume fraction (BV/TV). The ratio of peak amplitudes of the fast and slow waves nonlinearly increased as a function of BV/TV. These results open interesting perspective for acoustic assessment of cancellous bone micro-architecture and especially anisotropy that might lead to an improved assessment of bone strength.

  18. Per-colorant-channel color barcodes for mobile applications: an interference cancellation framework.

    Science.gov (United States)

    Blasinski, Henryk; Bulan, Orhan; Sharma, Gaurav

    2013-04-01

    We propose a color barcode framework for mobile phone applications by exploiting the spectral diversity afforded by the cyan (C), magenta (M), and yellow (Y) print colorant channels commonly used for color printing and the complementary red (R), green (G), and blue (B) channels, respectively, used for capturing color images. Specifically, we exploit this spectral diversity to realize a three-fold increase in the data rate by encoding independent data in the C, M, and Y print colorant channels and decoding the data from the complementary R, G, and B channels captured via a mobile phone camera. To mitigate the effect of cross-channel interference among the print-colorant and capture color channels, we develop an algorithm for interference cancellation based on a physically-motivated mathematical model for the print and capture processes. To estimate the model parameters required for cross-channel interference cancellation, we propose two alternative methodologies: a pilot block approach that uses suitable selections of colors for the synchronization blocks and an expectation maximization approach that estimates the parameters from regions encoding the data itself. We evaluate the performance of the proposed framework using specific implementations of the framework for two of the most commonly used barcodes in mobile applications, QR and Aztec codes. Experimental results show that the proposed framework successfully overcomes the impact of the color interference, providing a low bit error rate and a high decoding rate for each of the colorant channels when used with a corresponding error correction scheme.

  19. An OFDM Receiver with Frequency Domain Diversity Combined Impulsive Noise Canceller for Underwater Network.

    Science.gov (United States)

    Saotome, Rie; Hai, Tran Minh; Matsuda, Yasuto; Suzuki, Taisaku; Wada, Tomohisa

    2015-01-01

    In order to explore marine natural resources using remote robotic sensor or to enable rapid information exchange between ROV (remotely operated vehicles), AUV (autonomous underwater vehicle), divers, and ships, ultrasonic underwater communication systems are used. However, if the communication system is applied to rich living creature marine environment such as shallow sea, it suffers from generated Impulsive Noise so-called Shrimp Noise, which is randomly generated in time domain and seriously degrades communication performance in underwater acoustic network. With the purpose of supporting high performance underwater communication, a robust digital communication method for Impulsive Noise environments is necessary. In this paper, we propose OFDM ultrasonic communication system with diversity receiver. The main feature of the receiver is a newly proposed Frequency Domain Diversity Combined Impulsive Noise Canceller. The OFDM receiver utilizes 20-28 KHz ultrasonic channel and subcarrier spacing of 46.875 Hz (MODE3) and 93.750 Hz (MODE2) OFDM modulations. In addition, the paper shows Impulsive Noise distribution data measured at a fishing port in Okinawa and at a barge in Shizuoka prefectures and then proposed diversity OFDM transceivers architecture and experimental results are described. By the proposed Impulsive Noise Canceller, frame bit error rate has been decreased by 20-30%.

  20. An OFDM Receiver with Frequency Domain Diversity Combined Impulsive Noise Canceller for Underwater Network

    Directory of Open Access Journals (Sweden)

    Rie Saotome

    2015-01-01

    Full Text Available In order to explore marine natural resources using remote robotic sensor or to enable rapid information exchange between ROV (remotely operated vehicles, AUV (autonomous underwater vehicle, divers, and ships, ultrasonic underwater communication systems are used. However, if the communication system is applied to rich living creature marine environment such as shallow sea, it suffers from generated Impulsive Noise so-called Shrimp Noise, which is randomly generated in time domain and seriously degrades communication performance in underwater acoustic network. With the purpose of supporting high performance underwater communication, a robust digital communication method for Impulsive Noise environments is necessary. In this paper, we propose OFDM ultrasonic communication system with diversity receiver. The main feature of the receiver is a newly proposed Frequency Domain Diversity Combined Impulsive Noise Canceller. The OFDM receiver utilizes 20–28 KHz ultrasonic channel and subcarrier spacing of 46.875 Hz (MODE3 and 93.750 Hz (MODE2 OFDM modulations. In addition, the paper shows Impulsive Noise distribution data measured at a fishing port in Okinawa and at a barge in Shizuoka prefectures and then proposed diversity OFDM transceivers architecture and experimental results are described. By the proposed Impulsive Noise Canceller, frame bit error rate has been decreased by 20–30%.

  1. Cancellation of spurious arrivals in Green's function extraction and the generalized optical theorem

    Science.gov (United States)

    Snieder, R.; Van Wijk, K.; Haney, M.; Calvert, R.

    2008-01-01

    The extraction of the Green's function by cross correlation of waves recorded at two receivers nowadays finds much application. We show that for an arbitrary small scatterer, the cross terms of scattered waves give an unphysical wave with an arrival time that is independent of the source position. This constitutes an apparent inconsistency because theory predicts that such spurious arrivals do not arise, after integration over a complete source aperture. This puzzling inconsistency can be resolved for an arbitrary scatterer by integrating the contribution of all sources in the stationary phase approximation to show that the stationary phase contributions to the source integral cancel the spurious arrival by virtue of the generalized optical theorem. This work constitutes an alternative derivation of this theorem. When the source aperture is incomplete, the spurious arrival is not canceled and could be misinterpreted to be part of the Green's function. We give an example of how spurious arrivals provide information about the medium complementary to that given by the direct and scattered waves; the spurious waves can thus potentially be used to better constrain the medium. ?? 2008 The American Physical Society.

  2. Full-diversity partial interference cancellation for multi-user wireless relaying networks

    KAUST Repository

    El Astal, M. T O

    2013-12-01

    We focus on the uplink channel of multi-user wireless relaying networks in a coverage extension scenario. The network consists of two users, a single half duplex (HD) relay and a destination, all equipped with multiple antennas. Perfect channel state information (CSI) is assumed to be available exclusively at the receiving nodes (i.e., the relay and the destination) while the users are assumed to be completely blind. The communication through the considered network takes place over two phases. During the first phase, both users send their information concurrently to the relay. The second phase consists of decoding the received data and forwarding it simultaneously to the destination. A transmission scheme that achieves full-diversity under partial interference cancellation (PIC) group decoding is proposed. Unlike many existing schemes, it allows the concurrent transmission in both phases while achieving the full-diversity gain of full time division multiple access (TDMA) transmission regardless of the number of antennas at each node. Numerical comparison with existing schemes in the literature is provided to corroborate our theoretical claims. It is found that our interference cancellation (IC) scheme clearly outperforms existing schemes at the expense of an affordable increase in decoding complexity at both of the relay and destination. © 2013 IEEE.

  3. Relationships among ultrasonic and mechanical properties of cancellous bone in human calcaneus in vitro.

    Science.gov (United States)

    Wear, Keith A; Nagaraja, Srinidhi; Dreher, Maureen L; Sadoughi, Saghi; Zhu, Shan; Keaveny, Tony M

    2017-10-01

    Clinical bone sonometers applied at the calcaneus measure broadband ultrasound attenuation and speed of sound. However, the relation of ultrasound measurements to bone strength is not well-characterized. Addressing this issue, we assessed the extent to which ultrasonic measurements convey in vitro mechanical properties in 25 human calcaneal cancellous bone specimens (approximately 2×4×2cm). Normalized broadband ultrasound attenuation, speed of sound, and broadband ultrasound backscatter were measured with 500kHz transducers. To assess mechanical properties, non-linear finite element analysis, based on micro-computed tomography images (34-micron cubic voxel), was used to estimate apparent elastic modulus, overall specimen stiffness, and apparent yield stress, with models typically having approximately 25-30 million elements. We found that ultrasound parameters were correlated with mechanical properties with R=0.70-0.82 (pmechanical properties beyond that provided by bone quantity alone (p≤0.05). Adding ultrasound variables to linear regression models based on bone quantity improved adjusted squared correlation coefficients from 0.65 to 0.77 (stiffness), 0.76 to 0.81 (apparent modulus), and 0.67 to 0.73 (yield stress). These results indicate that ultrasound can provide complementary (to bone quantity) information regarding mechanical behavior of cancellous bone. Published by Elsevier Inc.

  4. Lyapunov Tuning of the Leaky Lms Algorithm for Single-Source Single-Point Noise Cancellation

    Science.gov (United States)

    Cartes, D. A.; Ray, L. R.; Collier, R. D.

    2003-09-01

    Least-mean square (LMS) algorithms, which are commonly used for adaptive feedforward noise cancellation, have performance issues related to insufficient excitation, non-stationary reference inputs, finite-precision arithmetic, quantisation noise and measurement noise. Such factors cause weight drift and potential instability in the conventional LMS algorithm. Here, we analyse the stability and performance of the leaky LMS algorithm, which is widely used to correct weight drift. A Lyapunov tuning method is developed to find an adaptive leakage parameter and adaptive step size that provide optimum performance and retain stability in the presence of measurement noise on the reference input of known variance. The method accounts for non-persistent excitation conditions and non-stationary reference inputs and requires no a priori knowledge of the reference input signal characteristics other than a lower bound on its magnitude or a minimum signal-to-noise ratio. The Lyapunov tuning method is demonstrated for three candidate adaptive leakage and step size parameter combinations, each of which is a function of the instantaneous measured reference input, measurement noise variance, and/or filter length. These candidates illustrate stability vs performance tradeoffs in the leaky LMS algorithm elicited through the Lyapunov tuning method. The performance of each candidate Lyapunov tuned algorithm is evaluated experimentally in a single source, single-point acoustic noise cancellation system.

  5. Application of Active Noise Cancellation for Source Identification and Monitoring in a Modal Environment

    Science.gov (United States)

    Chiu, Wen-Shyang

    1990-01-01

    Faulty bearing detection and diagnosis in complex machines often encounter a problem in that the bearing signal may be masked by excessive noise. The ability to process the diagnosed signal to improve its signal-to-noise density ratio (SNR) is critical in detecting and diagnosing the bearing's fault in its early stage. The objective of this research was to develop a real-time monitoring technique for the detection and diagnosis of an incipient bearing failure when the bearing signal is corrupted by the presence of significant background noise. The original contribution of this work is a new approach to separate the diagnosed signal from structural noise based on the adaptive noise cancellation technique (ANC). The ANC makes use of an adaptive filtering process which is based on the least mean square algorithm (LMS) of Widrow and Hoff. A real-time, PC-hosted adaptive noise canceller with the capability of high frequency range application has been developed using the Motorola DSP56000/56200 system. Power spectrum, kurtosis, and cepstrum are used to detect and diagnose the bearing's fault subsequent to the application of the ANC. This real-time monitoring technique was applied to monitor the operating conditions of a ball bearing in a motor/pump system. The bearing signal is masked by structural noise from structural resonances and from the pump. Results show that the ANC can remove the structural noise from the signal so that the statistical and spectral analysis techniques for bearing monitoring can be effectively used.

  6. An efficient method for ectopic beats cancellation based on radial basis function.

    Science.gov (United States)

    Mateo, Jorge; Torres, Ana; Rieta, José J

    2011-01-01

    The analysis of the surface Electrocardiogram (ECG) is the most extended noninvasive technique in cardiological diagnosis. In order to properly use the ECG, we need to cancel out ectopic beats. These beats may occur in both normal subjects and patients with heart disease, and their presence represents an important source of error which must be handled before any other analysis. This paper presents a method for electrocardiogram ectopic beat cancellation based on Radial Basis Function Neural Network (RBFNN). A train-able neural network ensemble approach to develop customized electrocardiogram beat classifier in an effort to further improve the performance of ECG processing and to offer individualized health care is presented. Six types of beats including: Normal Beats (NB); Premature Ventricular Contractions (PVC); Left Bundle Branch Blocks (LBBB); Right Bundle Branch Blocks (RBBB); Paced Beats (PB) and Ectopic Beats (EB) are obtained from the MIT-BIH arrhythmia database. Four morphological features are extracted from each beat after the preprocessing of the selected records. Average Results for the RBFNN based method provided an ectopic beat reduction (EBR) of (mean ± std) EBR = 7, 23 ± 2.18 in contrast to traditional compared methods that, for the best case, yielded EBR = 4.05 ± 2.13. The results prove that RBFNN based methods are able to obtain a very accurate reduction of ectopic beats together with low distortion of the QRST complex.

  7. Ground clutter cancellation in incoherent radars: solutions for EISCAT Svalbard radar

    Directory of Open Access Journals (Sweden)

    T. Turunen

    2000-09-01

    Full Text Available Incoherent scatter radars measure ionosphere parameters using modified Thomson scatter from free electrons in the target (see e.g. Hagfors, 1997. The integrated cross section of the ionospheric scatterers is extremely small and the measurements can easily be disturbed by signals returned by unwanted targets. Ground clutter signals, entering via the antenna side lobes, can render measurements at the nearest target ranges totally impossible. The EISCAT Svalbard Radar (ESR, which started measurements in 1996, suffers from severe ground clutter and the ionosphere cannot be measured in any simple manner at ranges less than about 120–150 km, depending on the modulation employed. If the target and clutter signals have different, and clearly identifiable, properties then, in principle, there are always ways to eliminate the clutter. In incoherent scatter measurements, differences in the coherence times of the wanted and unwanted signals can be used for clutter cancellation. The clutter cancellation must be applied to all modulations, usually alternating codes in modern experiments, used for shorter ranges. Excellent results have been obtained at the ESR using a simple pulse-to-pulse clutter subtraction method, but there are also other possibilities.Key words: Radio science (ionospheric physics; signal processing; instruments and techniques

  8. Estimation of critical and viscous frequencies for Biot theory in cancellous bone.

    Science.gov (United States)

    Hughes, Elinor R; Leighton, Timothy G; Petley, Graham W; White, Paul R; Chivers, Robert C

    2003-07-01

    The use of Biot theory for modelling ultrasonic wave propagation in porous media involves the definition of a "critical frequency" above which both fast and slow compressional waves will, in principle, propagate. Critical frequencies have been evaluated for healthy and osteoporotic cancellous bone filled with water or marrow, using data from the literature. The range of pore sizes in bone gives rise to a critical frequency band rather than a single critical frequency, the mean of which is lower for osteoporotic bone than normal bone. However, the critical frequency is a theoretical concept and previous researchers considered a more realistic "viscous frequency" above which both fast and slow waves may be experimentally observed. Viscous frequencies in bone are found to be several orders of magnitude greater than calculated critical frequencies. Whereas two waves may well be observed at all ultrasonic frequencies for water-filled cancellous bone at 20 degrees C, it is probable megahertz frequencies would be needed for observation of two waves in vivo.

  9. Adsorption and release of antibiotics from morselized cancellous bone. In vitro studies of 8 antibiotics.

    Science.gov (United States)

    Witsø, E; Persen, L; Løseth, K; Bergh, K

    1999-06-01

    We studied the basic release patterns of antibiotics from cancellous bone in vitro. Antibiotic-impregnated bone was compressed into a wire-mesh cylinder and the release of antibiotic was assessed by two different in vitro methods: agar diffusion and broth elution. The zones of inhibition were measured on seeded agar and the amounts of antibiotics released in elution tubes were assessed by a bioassay. The study continued for 21 days with daily transfer of the cylinders. The results indicated that benzylpenicillin, dicloxacillin, cephalotin, netilmicin, clindamycin, vancomycin, ciprofloxacin and rifampicin were adsorbed to cancellous bone in vitro. Compared to broth elution, agar diffusion showed a prolonged period of release, owing to the small amounts of antibiotic leaking out of the cylinder into the agar. The betalactams had antibacterial activity in broth for a shorter time than the other antibiotics. The release patterns of the betalactams were similar, in spite of their differences in thermal stability. Only rifampicin showed a concentration higher than MIC for longer than 21 days.

  10. Near-infrared phase cancellation instrument for fast and accurate localization of fluorescent heterogeneity

    Science.gov (United States)

    Chen, Yu; Mu, Chenpeng; Intes, Xavier; Blessington, Dana; Chance, Britton

    2003-07-01

    Near-infrared (NIR) diffuse optical imaging has become a promising method for noninvasive in vivo detection of breast cancer with intrinsic chromophores. Recent developments in molecular specific targeting fluorescent contrast agents offer high tumor to normal tissue contrast, and are capable of selectively labeling various precancer/cancer signatures, thus enhancing both the sensitivity and specificity of cancer detection. To detect a subsurface tumor labeled by fluorescent contrast agents, we have developed a phase cancellation imaging system for fast localization of fluorescent object embedded several centimeters deep inside the turbid media. The instrument is a frequency domain (50 MHz) phase modulation system with dual out-of-phase sources. The excitation wavelength is 780 nm and the fluorescence photons are collected through an 830±10 nm band-pass filter. Localization of fluorescent objects inside the scattering media is accurate using a phase cancellation device. The localization error for a 5 mm diameter sphere filled with 1 nanomole fluorescent dye and 3 cm deep inside the turbid media is about 2 mm. The accuracy of the localization suggests that this system could be helpful in guiding clinical fine-needle biopsy, and would benefit the early detection of breast tumors.

  11. High Dynamic Range RF Front End with Noise Cancellation and Linearization for WiMAX Receivers

    Directory of Open Access Journals (Sweden)

    J.-M. Wu

    2012-06-01

    Full Text Available This research deals with verification of the high dynamic range for a heterodyne radio frequency (RF front end. A 2.6 GHz RF front end is designed and implemented in a hybrid microwave integrated circuit (HMIC for worldwide interoperability for microwave access (WiMAX receivers. The heterodyne RF front end consists of a low-noise amplifier (LNA with noise cancellation, an RF bandpass filter (BPF, a downconverter with linearization, and an intermediate frequency (IF BPF. A noise canceling technique used in the low-noise amplifier eliminates a thermal noise and then reduces the noise figure (NF of the RF front end by 0.9 dB. Use of a downconverter with diode linearizer also compensates for gain compression, which increases the input-referred third-order intercept point (IIP3 of the RF front end by 4.3 dB. The proposed method substantially increases the spurious-free dynamic range (DRf of the RF front end by 3.5 dB.

  12. Improved Successive Interference Cancellation for MIMO/UWB-Based Wireless Body Area Network

    Directory of Open Access Journals (Sweden)

    M. Jayasheela

    2012-01-01

    Full Text Available In body area networks, various sensors are attached to clothing or on the body or even implanted under the skin. The sensors measure such as heart beat, the record of prolonged electrocardiogram, blood pressure, and so on. In this paper, an improved Successive interference cancellation (SIC scheme based on zero correlation zone sequences is proposed. Here ZCZ is used as a random code for TH PPM UWB system. Nodes in a WBAN are connected through wireless communication channel within a very close range. The decrease in internode distance leads to interference between devices. To reduce this interference, an enhanced successive interference cancellation scheme based on ZCZ with optimal ordering is adopted. Because of zero correlation property of ZCZ, the performance of TH PPM UWB system through WBAN channel with ZCZ sequences outperforms performance of existing zero correlation duration code. In this paper, performance of UWB system for various modulation schemes are compared. Performance of UWB/MIMO (2×2 system employing SIC with optimal ordering using ZCZ codes also compared with pseudorandom (PN and ZCD codes. Simulation results are obtained using sample biological functions as input to the proposed TH PPM UWB/MIMO (2×2 system with m-ZCZ codes in WBAN environment with multiple devices.

  13. Quality of intertrochanteric cancellous bone as predictor of femoral stem RSA migration in cementless total hip arthroplasty.

    Science.gov (United States)

    Moritz, Niko; Alm, Jessica J; Lankinen, Petteri; Mäkinen, Tatu J; Mattila, Kimmo; Aro, Hannu T

    2011-01-11

    In cementless total hip arthroplasty, osteoporosis may jeopardize the achievement of immediate stability and lead to migration of anatomically shaped femoral stems. Poor quality of proximal cancellous bone per se may also affect the rate of osseointegration. In a selected group of female total hip arthroplasty patients (mean age 64 years) with unremarkable medical history, intertrochanteric cancellous bone biopsy was taken from the site of stem implantation. Local bone quality, determined by structural μCT imaging and destructive compression testing of the biopsy tissue, was used as the predictor of three-dimensional stem migration determined by radiostereometric analysis (RSA) up to 24 months. The patients exhibited major differences in mechanical properties of the intertrochanteric cancellous bone, which were closely related to the structural parameters calculated from μCT data. Unexpectedly, the major differences observed in the quality of trochanteric cancellous bone had only minor reflections in the RSA migration of the femoral stems. In statistical analysis, the μCT-based bone mineral density quartile (low, middle, high) was the only significant predictor for stem translation at 24 months (p=0.022) but only a small portion (R(2)=0.16) of the difference in translation could be explained by changes in bone mineral density quartile. None of the other parameters investigated predicted stem migration in translation or rotation. In conclusion, poor quality of intertrochanteric cancellous bone seems to contribute to the risk of implant migration less than expected. Probably also the importance of surgical preservation of intertrochanteric cancellous bone has been over-emphasized for osseointegration of cementless stem. Copyright © 2010 Elsevier Ltd. All rights reserved.

  14. Investigation of LO-leakage cancellation and DC-offset influence on flicker-noise in X-band mixers

    DEFF Research Database (Denmark)

    Michaelsen, Rasmus; Johansen, Tom; Tamborg, Kjeld

    2012-01-01

    This paper describes an investigation on the influences in 1/f noise of LO-leakage and DC-offset cancellation for X-band mixers. Conditions for LO-leakage cancellation and zero DC-offset is derived. Measurements on a double balanced diode mixer shows an improvement in noise figure from 14.3dB to 12.......1dB at 10KHz, while maintaining a noise figure of 6.2dB at 1MHz. LO-RF isolation is improved from 18dB to 60dB. The 1/f noise is shown to increase with increasing DC-offset....

  15. Cancelled requests:a study of interlibrary loan requests for items held in a medical library collection.

    Science.gov (United States)

    O'Brien, Kevin

    2004-01-01

    This paper presents the results of a study to document and analyze a sample of interlibrary loan requests received from library patrons of an academic medical library for items that are actually held in the collection of the library. This category is referred to as cancelled requests. The purpose of the study was to attempt to measure the degree to which library patrons are not making the best possible use of the collection and understand why this was taking place. Suggestions are presented for steps to lower the cancellation rate.

  16. 40 CFR 164.21 - Contents of a denial of registration, notice of intent to cancel a registration, or notice of...

    Science.gov (United States)

    2010-07-01

    ... classification. (a) Contents. The denial of registration or a notice of intent to cancel a registration or to... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Contents of a denial of registration, notice of intent to cancel a registration, or notice of intent to change a classification. 164.21 Section...

  17. Rescheduling of previously cancelled surgical cases does not increase variability in operating room workload when cases are scheduled based on maximizing efficiency of use of operating room time.

    Science.gov (United States)

    Epstein, Richard H; Dexter, Franklin

    2013-10-01

    Conceptually, cancelling a case close to the scheduled day of surgery increases variability in operating room (OR) workload (i.e., total hours of scheduled cases plus turnovers), creating managerial problems. However, in our recent study of an OR scheduling office, cancellations (slightly) reduced variability in workload among days. If a relatively low incidence of cancellations does not cause increased variability in workload, this would be a useful finding when focusing strategic OR management initiatives. However, the previous study considered only the effect on the schedule for the day the cancelled case originally was scheduled to be performed, not the future date on which the case was performed. For 90% of cancelled cases, the patient later underwent the same or a similar procedure at the studied hospital. Thus, the OR schedule at 7:00 am each day over 2 years could be used to study case rescheduling. The primary end point, calculated for each surgeon, was the difference of 2 ratios. The first ratio was the proportion of scheduled workload attributable to previously cancelled cases, among all days for which the surgeon's workload exceeded the surgeon's median workload. The second ratio was that proportion among the other days when the surgeon performed at least 1 case. Means ± SEMs were calculated by random effects analysis, stratified by surgeon. From 7:00 am the working day before surgery through the day of surgery, 9.7% ± 0.6% of scheduled OR hours and 9.7% ± 0.5% of cases were cancelled. Among cases performed, 9.5% ± 0.5% of the scheduled hours and 9.5% ± 0.5% of the cases were previously cancelled (i.e., rescheduled to a later date and then performed). Surgeons' median workloads on days with at least 1 case were 8.3 ± 0.2 hours. The percentage of scheduled workload attributable to rescheduled cases was slightly less on days when the surgeon had larger than median workloads (-0.7% ± 0.3%, P = 0.022). Rescheduled cancelled cases did not increase

  18. Management implications for the perioperative surgical home related to inpatient case cancellations and add-on case scheduling on the day of surgery.

    Science.gov (United States)

    Epstein, Richard H; Dexter, Franklin

    2015-07-01

    The American Society of Anesthesiologists has embraced the concept of the Perioperative Surgical Home as a means through which anesthesiologists can add value to the health systems in which they practice. One key listed element of the Perioperative Surgical Home is to support "scheduling initiatives to reduce cancellations and increase efficiency." In this study, we explored the potential benefits of the Perioperative Surgical Home with respect to inpatient cancellations and add-on case scheduling. We evaluated 6 hypotheses related to the timing of inpatient cancellations and preoperative anesthesia evaluations. Inpatient cancellations were studied during 26 consecutive 4-week intervals between July 2012 and June 2014 at a tertiary care academic hospital. All timestamps related to scheduling, rescheduling, and cancellation activities were retrieved from the operating room (OR) case scheduling system. Timestamps when patients were seen by anesthesia residents were obtained from the preoperative evaluation system database. Batch mean methods were used to calculate means and SE. For cases cancelled, we determined whether, for "most" (>50%) cancellations, a subsequent procedure (of any type) was performed on the patient within 7 days of the cancellation. Comparisons with most and other fractions were assessed using the 1 group, 1-sided Student t test. We evaluated whether a few procedures were highly represented among the cancelled cases via the Herfindahl (Simpson's) index, comparing it with office decisions in each 1-hour bin between 6:00 AM and 3:59 PM. These values were compared with ≥1 decision per hour at the study hospital. Data from 24,735 scheduled inpatient cases were assessed. Cases cancelled after 7 AM on the day before or at any time on the scheduled day of surgery accounted for 22.6% ± 0.5% (SE) of the scheduled minutes all scheduled cases, and 26.8% ± 0.4% of the case volume (i.e., number of cases). Most (83.1% ± 0.6%, P 50%, P = 0.12), implying

  19. Adaptive HIFU noise cancellation for simultaneous therapy and imaging using an integrated HIFU/imaging transducer

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Jong Seob; Cannata, Jonathan Matthew; Shung, K Kirk [Department of Biomedical Engineering, NIH Resource Center for Medical Ultrasonic Transducer Technology, University of Southern California, Los Angeles, CA (United States)], E-mail: jongsjeo@usc.edu

    2010-04-07

    It was previously demonstrated that it is feasible to simultaneously perform ultrasound therapy and imaging of a coagulated lesion during treatment with an integrated transducer that is capable of high intensity focused ultrasound (HIFU) and B-mode ultrasound imaging. It was found that coded excitation and fixed notch filtering upon reception could significantly reduce interference caused by the therapeutic transducer. During HIFU sonication, the imaging signal generated with coded excitation and fixed notch filtering had a range side-lobe level of less than -40 dB, while traditional short-pulse excitation and fixed notch filtering produced a range side-lobe level of -20 dB. The shortcoming is, however, that relatively complicated electronics may be needed to utilize coded excitation in an array imaging system. It is for this reason that in this paper an adaptive noise canceling technique is proposed to improve image quality by minimizing not only the therapeutic interference, but also the remnant side-lobe 'ripples' when using the traditional short-pulse excitation. The performance of this technique was verified through simulation and experiments using a prototype integrated HIFU/imaging transducer. Although it is known that the remnant ripples are related to the notch attenuation value of the fixed notch filter, in reality, it is difficult to find the optimal notch attenuation value due to the change in targets or the media resulted from motion or different acoustic properties even during one sonication pulse. In contrast, the proposed adaptive noise canceling technique is capable of optimally minimizing both the therapeutic interference and residual ripples without such constraints. The prototype integrated HIFU/imaging transducer is composed of three rectangular elements. The 6 MHz center element is used for imaging and the outer two identical 4 MHz elements work together to transmit the HIFU beam. Two HIFU elements of 14.4 mm x 20.0 mm dimensions

  20. Hearing screening for school children: utility of noise-cancelling headphones.

    Science.gov (United States)

    Lo, Ada Hiu Chong; McPherson, Bradley

    2013-05-24

    Excessive ambient noise in school settings is a major concern for school hearing screening as it typically masks pure tone test stimuli (particularly 500 Hz and below). This results in false positive findings and subsequent unnecessary follow-up. With advances in technology, noise-cancelling headphones have been developed that reduce low frequency noise by superimposing an anti-phase signal onto the primary noise. This research study examined the utility of noise-cancelling headphone technology in a school hearing screening environment. The present study compared the audiometric screening results obtained from two air-conduction transducers-Sennheiser PXC450 noise-cancelling circumaural headphones (NC headphones) and conventional TDH-39 supra-aural earphones. Pure-tone hearing screening results (500 Hz to 4000 Hz, at 30 dB HL and 25 dB HL) were obtained from 232 school children, aged 6 to 8 years, in four Hong Kong primary schools. Screening outcomes revealed significant differences in referral rates between TDH-39 earphones and NC headphones for both 30 dB HL and 25 dB HL criteria, regardless of the inclusion or exclusion of 500 Hz results. The kappa observed agreement (OA) showed that at both screening intensities, the transducers' referral agreement value for the 500 Hz inclusion group was smaller than for the 500 Hz exclusion group. Individual frequency analysis showed that the two transducers screened similarly at 1000 Hz and 2000 Hz at 25 dB HL, as well as at both 30 dB HL and 25 dB HL screening levels for 4000 Hz. Statistically significant differences were found for 500 Hz at 30 dB HL and at 25 dB HL, and for 1000 Hz and 2000 Hz at 30 dB HL. OA for individual frequencies showed weaker intra-frequency agreement between the two transducers at 500 Hz at both intensity criterion levels than at higher frequencies. NC headphones screening results differed from those obtained from TDH-39 earphones, with lower referral rates at 500 Hz, particularly at the 25 dB HL

  1. Hearing screening for school children: utility of noise-cancelling headphones

    Science.gov (United States)

    2013-01-01

    Background Excessive ambient noise in school settings is a major concern for school hearing screening as it typically masks pure tone test stimuli (particularly 500 Hz and below). This results in false positive findings and subsequent unnecessary follow-up. With advances in technology, noise-cancelling headphones have been developed that reduce low frequency noise by superimposing an anti-phase signal onto the primary noise. This research study examined the utility of noise-cancelling headphone technology in a school hearing screening environment. Methods The present study compared the audiometric screening results obtained from two air-conduction transducers—Sennheiser PXC450 noise-cancelling circumaural headphones (NC headphones) and conventional TDH-39 supra-aural earphones. Pure-tone hearing screening results (500 Hz to 4000 Hz, at 30 dB HL and 25 dB HL) were obtained from 232 school children, aged 6 to 8 years, in four Hong Kong primary schools. Results Screening outcomes revealed significant differences in referral rates between TDH-39 earphones and NC headphones for both 30 dB HL and 25 dB HL criteria, regardless of the inclusion or exclusion of 500 Hz results. The kappa observed agreement (OA) showed that at both screening intensities, the transducers’ referral agreement value for the 500 Hz inclusion group was smaller than for the 500 Hz exclusion group. Individual frequency analysis showed that the two transducers screened similarly at 1000 Hz and 2000 Hz at 25 dB HL, as well as at both 30 dB HL and 25 dB HL screening levels for 4000 Hz. Statistically significant differences were found for 500 Hz at 30 dB HL and at 25 dB HL, and for 1000 Hz and 2000 Hz at 30 dB HL. OA for individual frequencies showed weaker intra-frequency agreement between the two transducers at 500 Hz at both intensity criterion levels than at higher frequencies. Conclusions NC headphones screening results differed from those obtained from TDH-39 earphones, with lower referral

  2. Study of the optical crosstalk in a heterodyne displacement gauge with cancelable circuit

    Science.gov (United States)

    Donazzan, Alberto; Naletto, Giampiero; Pelizzo, Maria G.

    2017-06-01

    One main focus of high precision heterodyne displacement interferometers are the means of splitting and merging for the reference (R) and measurement (M) beams when a cancelable circuit is implemented. Optical mixing of R and M gives birth to a systematc error called cyclic error, which appears as a periodic offset between the detected displacement and the actual one. A simple derivation of the cyclic error due to optical mixing is proposed for the cancelable circuit design. R and M beatings are collected by two photodiodes and conveniently converted by transimpedance amplifiers, such that the output signals are turned into ac-coupled voltages. The detected phase can be calculated as a function of the real phase (a change in optical path difference) in the case of zero-crossing detection. What turns out is a cyclic non-linearity which depends on the actual phase and on the amount of optical power leakage from the R channel into the M channel and vice versa. We then applied this result to the prototype of displacement gauge we are developing, which implements the cancelable circuit design with wavefront division. The splitting between R and M is done with a double coated mirror with a central hole, tilted by 45° with respect to the surface normal. The interferometer features two removable diffraction masks, respectively located before the merging point (a circular obscuration) and before the recombination point (a ring obscuration). In order to predict the extent of optical mixing between R and M, the whole layout was simulated by means of the Zemax ® Physical Optics Propagation (POP) tool. After the model of our setup was built and qualitatively verified, we proceeded by calculating the amount of optical leakages in various configurations: with and without the diffraction masks as well as for different sizes of both the holey mirror and the diffraction masks. The corrisponding maximum displacement error was then calculated for every configuration thanks to the

  3. Ununited diaphyseal forearm fractures with segmental defects: plate fixation and autogenous cancellous bone-grafting.

    Science.gov (United States)

    Ring, David; Allende, Christian; Jafarnia, Koroush; Allende, Bartolome T; Jupiter, Jesse B

    2004-11-01

    With current techniques of plate-and-screw fixation, diaphyseal nonunions of the radius and ulna are unusual. The few reports that have been published have discussed the use of structural corticocancellous bone grafts for the treatment of atrophic nonunions that are associated with osseous defects. We reviewed the rate of union and the functional results in association with the use of plate-and-screw fixation and autogenous cancellous (nonstructural) bone grafts. Thirty-five patients with an atrophic ununited diaphyseal fracture of the forearm were treated with 3.5-mm plate-and-screw fixation and autogenous cancellous bone-grafting. A segmental osseous defect with an average size of 2.2 cm (range, 1 to 6 cm) was present in each patient. Twenty of the original fractures had been open. Eleven patients had had treatment of a deep infection before referral to us. The nonunion involved both forearm bones in eight patients, the radius alone in sixteen patients, and the ulna alone in eleven patients. The atrophic nonunion was associated with an open fracture in twenty patients, suboptimal fixation in twenty-two, a fracture-dislocation of the forearm in nine, and infection in eleven. All fractures healed without additional intervention within six months. Two patients had a subsequent Darrach resection of the distal part of the ulna for the treatment of arthrosis of the distal radioulnar joint. After an average duration of follow-up of forty-three months, the final arc of motion averaged 121 degrees in the forearm, 131 degrees at the elbow, and 137 degrees at the wrist, with an average grip strength of 83% compared with that of the contralateral limb. According to the system of Anderson and colleagues, five patients had an excellent result, eighteen had a satisfactory result, eleven had an unsatisfactory result (because of elbow stiffness related to associated elbow injuries in three and because of wrist stiffness in eight), and one had a poor result (because of malunion

  4. 49 CFR 40.269 - What problems cause an alcohol test to be cancelled unless they are corrected?

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false What problems cause an alcohol test to be... Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Problems in Alcohol Testing § 40.269 What problems cause an alcohol test to be cancelled unless they are corrected? As a BAT...

  5. Cancellation of the Annual Facility Grant Creates More Shortfalls for School Districts. BCTF Research Report. Section V. 2009-EF-02

    Science.gov (United States)

    White, Margaret

    2009-01-01

    The Ministry of Education recently announced the cancellation of the Annual Facility Grant (AFG) for 2009-10, resulting in a loss of $110 million dollars in revenue to school districts. This decision comes after Boards of Education submitted their 2009-10 balanced budgets by June 30, based on expected revenues for the coming school year. Boards of…

  6. Cancellations Between Two-Loop Contributions to the Electron Electric Dipole Moment with a CP-Violating Higgs Sector.

    Science.gov (United States)

    Bian, Ligong; Liu, Tao; Shu, Jing

    2015-07-10

    We present a class of cancellation conditions for suppressing the total contributions of Barr-Zee diagrams to the electron electric dipole moment (eEDM). Such a cancellation is of particular significance after the new eEDM upper limit was released by the ACME Collaboration, which strongly constrains the allowed magnitude of CP violation in Higgs couplings and hence the feasibility of electroweak baryogenesis (EWBG). Explicitly, if both the CP-odd Higgs-photon-photon (Z boson) and the CP-odd Higgs-electron-positron couplings are turned on, a cancellation may occur either between the contributions of a CP-mixing Higgs boson, with the other Higgs bosons being decoupled, or between the contributions of CP-even and CP-odd Higgs bosons. With a cancellation, large CP violation in the Higgs sector is still allowed, yielding successful EWBG. The reopened parameter regions would be probed by future neutron, mercury EDM measurements, and direct measurements of Higgs CP properties at the Large Hadron Collider Run II and future colliders.

  7. Intercarrier interference reduction in MC-CDMA system through second order duobinary coded phase rotated conjugate cancellation scheme.

    Science.gov (United States)

    Chitra, S; Kumaratharan, N

    2015-01-01

    Multi-carrier code division multiple access (MC-CDMA) technique is one of the strong candidates for next generation wireless mobile communication systems. Multi-carrier systems are very much sensitive to carrier frequency offset (CFO) results in intercarrier interference (ICI). To mitigate ICI without any spectral loss, a second order duobinary coded phase rotated conjugate cancellation algorithm is proposed in this paper. In the conventional phase rotated conjugate cancellation (PRCC) technique, one path carries the MC-CDMA signal with a phase spin of ϕ and the other path carries the conjugate of the first path signal with -ϕ phase spin. This artificial phase rotation allows the transmitter to tune the transmitted signals so that the ICI effects could be mutually cancelled at the receiver. Although the PRCC technique reduces the spectral efficiency, the limitation can be overcome by the joint second order duobinary coding scheme with PRCC technique. In the proposed method, the correlative coding between the binary symbols modulated on adjacent subcarriers is used to reduce the ICI without any spectral loss. Simulation results show that the proposed PRCC method provides better carrier to interference ratio (CIR) and bit error rate (BER) performances compared to the conventional conjugate cancellation (CC) technique.

  8. A Small-Area Self-Biased Wideband CMOS Balun LNA with Noise Cancelling and Gain Enhancement

    DEFF Research Database (Denmark)

    Bruun, Erik; Andreani, Pietro; Custódio, J. R.

    2010-01-01

    In this paper we present a low-power and small-area balun LNA. The proposed inverter-based topology uses selfbiasing and noise cancelling, yielding a very robust LNA with a low NF. Comparing this circuit with a conventional inverterbased circuit, we obtain a ∼3 dB enhancement in voltage gain...

  9. A deconvolution method for deriving the transit time spectrum for ultrasound propagation through cancellous bone replica models.

    Science.gov (United States)

    Langton, Christian M; Wille, Marie-Luise; Flegg, Mark B

    2014-04-01

    The acceptance of broadband ultrasound attenuation for the assessment of osteoporosis suffers from a limited understanding of ultrasound wave propagation through cancellous bone. It has recently been proposed that the ultrasound wave propagation can be described by a concept of parallel sonic rays. This concept approximates the detected transmission signal to be the superposition of all sonic rays that travel directly from transmitting to receiving transducer. The transit time of each ray is defined by the proportion of bone and marrow propagated. An ultrasound transit time spectrum describes the proportion of sonic rays having a particular transit time, effectively describing lateral inhomogeneity of transit times over the surface of the receiving ultrasound transducer. The aim of this study was to provide a proof of concept that a transit time spectrum may be derived from digital deconvolution of input and output ultrasound signals. We have applied the active-set method deconvolution algorithm to determine the ultrasound transit time spectra in the three orthogonal directions of four cancellous bone replica samples and have compared experimental data with the prediction from the computer simulation. The agreement between experimental and predicted ultrasound transit time spectrum analyses derived from Bland-Altman analysis ranged from 92% to 99%, thereby supporting the concept of parallel sonic rays for ultrasound propagation in cancellous bone. In addition to further validation of the parallel sonic ray concept, this technique offers the opportunity to consider quantitative characterisation of the material and structural properties of cancellous bone, not previously available utilising ultrasound.

  10. Intercarrier interference reduction in MC-CDMA system through second order duobinary coded phase rotated conjugate cancellation scheme.

    Directory of Open Access Journals (Sweden)

    S Chitra

    Full Text Available Multi-carrier code division multiple access (MC-CDMA technique is one of the strong candidates for next generation wireless mobile communication systems. Multi-carrier systems are very much sensitive to carrier frequency offset (CFO results in intercarrier interference (ICI. To mitigate ICI without any spectral loss, a second order duobinary coded phase rotated conjugate cancellation algorithm is proposed in this paper. In the conventional phase rotated conjugate cancellation (PRCC technique, one path carries the MC-CDMA signal with a phase spin of ϕ and the other path carries the conjugate of the first path signal with -ϕ phase spin. This artificial phase rotation allows the transmitter to tune the transmitted signals so that the ICI effects could be mutually cancelled at the receiver. Although the PRCC technique reduces the spectral efficiency, the limitation can be overcome by the joint second order duobinary coding scheme with PRCC technique. In the proposed method, the correlative coding between the binary symbols modulated on adjacent subcarriers is used to reduce the ICI without any spectral loss. Simulation results show that the proposed PRCC method provides better carrier to interference ratio (CIR and bit error rate (BER performances compared to the conventional conjugate cancellation (CC technique.

  11. 78 FR 70901 - Debt That Is a Position in Personal Property That Is Part of a Straddle; Hearing Cancellation

    Science.gov (United States)

    2013-11-27

    ... straddle rules to a debt instrument. DATES: The public hearing originally scheduled for January 15, 2014 at... Internal Revenue Service 26 CFR Part 1 RIN 1545-BL24 Debt That Is a Position in Personal Property That Is...: Cancellation of a notice of public hearing on proposed rulemaking by cross-reference to temporary regulations...

  12. 14 CFR 105.15 - Information required and notice of cancellation or postponement of a parachute operation.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Information required and notice of cancellation or postponement of a parachute operation. 105.15 Section 105.15 Aeronautics and Space FEDERAL... postponement of a parachute operation. (a) Each person requesting an authorization under §§ 105.21(b) and 105...

  13. Glucocorticoid induced osteopenia in cancellous bone of sheep: validation of large animal model for spine fusion and biomaterial research

    DEFF Research Database (Denmark)

    Ding, Ming; Cheng, Liming; Bollen, Peter

    2010-01-01

    STUDY DESIGN: Glucocorticoid with low calcium and phosphorus intake induces osteopenia in cancellous bone of sheep. OBJECTIVE: To validate a large animal model for spine fusion and biomaterial research. SUMMARY OF BACKGROUND DATA: A variety of ovariectomized animals has been used to study...

  14. Enhanced Phase-Shifted Current Control for Harmonic Cancellation in Three-Phase Multiple Adjustable Speed Drive Systems

    DEFF Research Database (Denmark)

    Yang, Yongheng; Davari, Pooya; Zare, Firuz

    2017-01-01

    on the loading condition of each drive unit as well as the number of drives in parallel. In order to enhance the harmonic cancellation by means of the phase-shifted current control, the currents drawn by the rectifiers should be maintained almost at the same level. Thus, this paper firstly analyzes the impact...

  15. 78 FR 18594 - Notice of Cancelation for Call of the President's Advisory Council on Faith-Based and...

    Science.gov (United States)

    2013-03-27

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HEALTH AND HUMAN SERVICES Notice of Cancelation for Call of the President's Advisory Council on Faith-Based and... for Center for Faith-based and Neighborhood Partnerships at U.S. Department of Health and Human...

  16. Development of an active isolation mat based on dielectric elastomer stack actuators for mechanical vibration cancellation

    Science.gov (United States)

    Karsten, Roman; Flittner, Klaus; Haus, Henry; Schlaak, Helmut F.

    2013-04-01

    This paper describes the development of an active isolation mat for cancelation of vibrations on sensitive devices with a mass of up to 500 gram. Vertical disturbing vibrations are attenuated actively while horizontal vibrations are damped passively. The dimensions of the investigated mat are 140 × 140 × 20 mm. The mat contains 5 dielectric elastomer stack actuators (DESA). The design and the optimization of active isolation mat are realized by ANSYS FEM software. The best performance shows a DESA with air cushion mounted on its circumference. Within the mounting encased air increases static and reduces dynamic stiffness. Experimental results show that vibrations with amplitudes up to 200 μm can be actively eliminated.

  17. A single-ended CMOS sensing circuit for MEMS gyroscope with noise cancellation

    KAUST Repository

    Elsayed, Mohannad Yomn

    2010-06-01

    In this work, a complete single-ended readout circuit for capacitive MEMS gyroscope using chopper stabilization technique is presented. A novel noise cancellation technique is used to get rid of the bias noise. The circuit offers superior performance over state of the art readout circuits in terms of cost, gain, and noise for the given area and power consumption. The full circuit exhibits a gain of 58dB, a power dissipation of 1.3mW and an input referred noise of 12nV/√Hz. This would significantly improve the overall sensitivity of the gyroscope. The full circuit has been fabricated in 0.6um CMOS technology and it occupies an area of 0.4mm × 1mm. © 2010 IEEE.

  18. Performance Evaluation of Heart Sound Cancellation in FPGA Hardware Implementation for Electronic Stethoscope

    Directory of Open Access Journals (Sweden)

    Chun-Tang Chao

    2014-01-01

    Full Text Available This paper presents the design and evaluation of the hardware circuit for electronic stethoscopes with heart sound cancellation capabilities using field programmable gate arrays (FPGAs. The adaptive line enhancer (ALE was adopted as the filtering methodology to reduce heart sound attributes from the breath sounds obtained via the electronic stethoscope pickup. FPGAs were utilized to implement the ALE functions in hardware to achieve near real-time breath sound processing. We believe that such an implementation is unprecedented and crucial toward a truly useful, standalone medical device in outpatient clinic settings. The implementation evaluation with one Altera cyclone II–EP2C70F89 shows that the proposed ALE used 45% resources of the chip. Experiments with the proposed prototype were made using DE2-70 emulation board with recorded body signals obtained from online medical archives. Clear suppressions were observed in our experiments from both the frequency domain and time domain perspectives.

  19. Optimal Base Station Placement for Wireless Sensor Networks with Successive Interference Cancellation

    Directory of Open Access Journals (Sweden)

    Lei Shi

    2015-01-01

    Full Text Available We consider the base station placement problem for wireless sensor networks with successive interference cancellation (SIC to improve throughput. We build a mathematical model for SIC. Although this model cannot be solved directly, it enables us to identify a necessary condition for SIC on distances from sensor nodes to the base station. Based on this relationship, we propose to divide the feasible region of the base station into small pieces and choose a point within each piece for base station placement. The point with the largest throughput is identified as the solution. The complexity of this algorithm is polynomial. Simulation results show that this algorithm can achieve about 25% improvement compared with the case that the base station is placed at the center of the network coverage area when using SIC.

  20. A wideband CMOS inductorless low noise amplifier employing noise cancellation for digital TV tuner applications

    Science.gov (United States)

    Jihong, Zhang; Xuefei, Bai; Lu, Huang

    2013-09-01

    A wideband inductorless low noise amplifier for digital TV tuner applications is presented. The proposed LNA scheme uses a composite NMOS/PMOS cross-coupled transistor pair to provide partial cancellation of noise generated by the input transistors. The chip is implemented in SMIC 0.18 μm CMOS technology. Measurement shows that the proposed LNA achieves 12.2-15.2 dB voltage gain from 300 to 900 MHz, the noise figure is below 3.1 dB and has a minimum value of 2.3 dB, and the best input-referred 1-dB compression point (IP1dB) is - 17 dBm at 900 MHz. The core consumes 7 mA current with a supply voltage of 1.8 V and occupies an area of 0.5 × 0.35 mm2.

  1. A Review on Successive Interference Cancellation Scheme Based on Optical CDMA Network

    Science.gov (United States)

    Alsowaidi, N.; Eltaif, T.; Mokhtar, M. R.

    2014-12-01

    Due to various desirable features of optical code division multiple access (OCDMA), it is believed this technique once developed and commercially available will be an integral part of optical access networks. Optical CDMA system suffers from a problem called multiple access interference (MAI) which limits the number of active users, it occurs when number of active users share the same carriers. The aim of this paper is to review successive interference cancellation (SIC) scheme based on optical CDMA system. The paper also reviews the system performance in presence of shot noise, thermal noise, and phase-induced intensity noise (PIIN). A comprehensive review on the mathematical model of SIC scheme using direct detection (DS) and spectral amplitude coding (SAC) were presented in this article.

  2. Acoustic Echo Cancellation Embedded in Smart Transcoding Algorithm between 3GPP AMR-NB Modes

    Directory of Open Access Journals (Sweden)

    Emmanuel Rossignol Thepie Fapi

    2010-01-01

    Full Text Available Acoustic Echo Cancellation (AEC is a necessary feature for mobile devices when the acoustic coupling between the microphone and the loudspeaker affects the communication quality and intelligibility. When implemented inside the network, decoding is required to access the corrupted signal. The AEC performance is strongly degraded by nonlinearity introduced by speech codecs. The Echo Return Loss Enhancement (ERLE can be less than 10 dB for low bit rate speech codecs. We propose in this paper a coded domain AEC integrated in a smart transcoding strategy which directly modifies the Code Excited Linear Prediction (CELP parameters. The proposed system addresses simultaneously problems due to network interoperability and network voice quality enhancement. The ERLE performance of this new approach during transcoding between Adaptive Multirate-NarrowBand (AMR-NB modes is above 45 dB as required in Global System for Mobile Communications (GSM specifications.

  3. Background Noise Reduction Using Adaptive Noise Cancellation Determined by the Cross-Correlation

    Science.gov (United States)

    Spalt, Taylor B.; Brooks, Thomas F.; Fuller, Christopher R.

    2012-01-01

    Background noise due to flow in wind tunnels contaminates desired data by decreasing the Signal-to-Noise Ratio. The use of Adaptive Noise Cancellation to remove background noise at measurement microphones is compromised when the reference sensor measures both background and desired noise. The technique proposed modifies the classical processing configuration based on the cross-correlation between the reference and primary microphone. Background noise attenuation is achieved using a cross-correlation sample width that encompasses only the background noise and a matched delay for the adaptive processing. A present limitation of the method is that a minimum time delay between the background noise and desired signal must exist in order for the correlated parts of the desired signal to be separated from the background noise in the crosscorrelation. A simulation yields primary signal recovery which can be predicted from the coherence of the background noise between the channels. Results are compared with two existing methods.

  4. Evaluation of ultrasonic scattering in human cancellous bone by using a binary mixture model

    Energy Technology Data Exchange (ETDEWEB)

    Guo Xiasheng; Zhang Dong; Gong Xiufen [Institute of Acoustics, Key Lab of Modern Acoustics, Nanjing University, Nanjing 210093 (China)

    2007-01-07

    A weak scattering model based on small perturbations in a binary mixture is developed to estimate the ultrasonic scattering from human cancellous bone, which is modelled as a random isotropic continuum containing identical scatters. Ultrasonic scattering is determined by both velocity fluctuation and density fluctuation, when k{sup 2}a{sup 2} << 1 is satisfied. Two kinds of trabeculae thickness distributions, i.e. even distribution and Gauss distribution, are applied in the calculation of attenuation and backscattering. Frequency dependence of the backscatter coefficient is found to be Af{sup 3.13} and Af{sup 2.84} with the Gauss distribution and an even distribution, respectively. Both backscattering and attenuation change significantly against porosity for the case of high porosity. The predicted results are close to the measured ones from the literature. The errors of this theoretical model are also discussed in this paper.

  5. A compressed sensing based method with support refinement for impulse noise cancelation in DSL

    KAUST Repository

    Quadeer, Ahmed Abdul

    2013-06-01

    This paper presents a compressed sensing based method to suppress impulse noise in digital subscriber line (DSL). The proposed algorithm exploits the sparse nature of the impulse noise and utilizes the carriers, already available in all practical DSL systems, for its estimation and cancelation. Specifically, compressed sensing is used for a coarse estimate of the impulse position, an a priori information based maximum aposteriori probability (MAP) metric for its refinement, followed by least squares (LS) or minimum mean square error (MMSE) estimation for estimating the impulse amplitudes. Simulation results show that the proposed scheme achieves higher rate as compared to other known sparse estimation algorithms in literature. The paper also demonstrates the superior performance of the proposed scheme compared to the ITU-T G992.3 standard that utilizes RS-coding for impulse noise refinement in DSL signals. © 2013 IEEE.

  6. Frequency-Domain Adaptive Algorithm for Network Echo Cancellation in VoIP

    Directory of Open Access Journals (Sweden)

    Patrick A. Naylor

    2008-05-01

    Full Text Available We propose a new low complexity, low delay, and fast converging frequency-domain adaptive algorithm for network echo cancellation in VoIP exploiting MMax and sparse partial (SP tap-selection criteria in the frequency domain. We incorporate these tap-selection techniques into the multidelay filtering (MDF algorithm in order to mitigate the delay inherent in frequency-domain algorithms. We illustrate two such approaches and discuss their tradeoff between convergence performance and computational complexity. Simulation results show an improvement in convergence rate for the proposed algorithm over MDF and significantly reduced complexity. The proposed algorithm achieves a convergence performance close to that of the recently proposed, but substantially more complex improved proportionate MDF (IPMDF algorithm.

  7. Efficient algorithms for solution of interference cancellation and channel estimation for mobile OFDM system

    Science.gov (United States)

    Fan, Tong-liang; Wen, Yu-cang; Kadri, Chaibou

    Orthogonal frequency-division multiplexing (OFDM) is robust against frequency selective fading because of the increase of the symbol duration. However, the time-varying nature of the channel causes inter-carrier interference (ICI) which destroys the orthogonal of sub-carriers and degrades the system performance severely. To alleviate the detrimental effect of ICI, there is a need for ICI mitigation within one OFDM symbol. We propose an iterative Inter-Carrier Interference (ICI) estimation and cancellation technique for OFDM systems based on regularized constrained total least squares. In the proposed scheme, ICI aren't treated as additional additive white Gaussian noise (AWGN). The effect of Inter-Carrier Interference (ICI) and inter-symbol interference (ISI) on channel estimation is regarded as perturbation of channel. We propose a novel algorithm for channel estimation o based on regularized constrained total least squares. Computer simulations show that significant improvement can be obtained by the proposed scheme in fast fading channels.

  8. Computerizing the Cancellation Test1: Design, Development and Validation Study2

    Directory of Open Access Journals (Sweden)

    Sinan Hopcan

    2013-08-01

    Full Text Available This study is about the design, development and validation of computerized version of the Cancellation Test the paper - pencil version of which was first developed by Weintraub and Mesulam (1985. This computerized version consists of four sub-tests (organized letters, random letters, organized shapes and random shapes and administration panel where only researchers can access. The test was designed and developed according to universally accepted interface design principles. The test was formatively evaluated by administering to a small group of university students and was accordingly revised. The final version of the test was validated on 52 university students and the results were discussed together with the design and development processes.

  9. A New Variable Step-Size NLMS Algorithm and its Performance Evaluation in Echo Cancelling Applications

    Directory of Open Access Journals (Sweden)

    F. M. Casco-Sánchez

    2011-12-01

    Full Text Available In this work we introduce a variable step-size normalized LMS algorithm for adaptive echo cancellation in a FIRstructure. In the proposed scheme, the step-size adjustment is controlled by using the square of the cross-correlationbetween the squared output error and the adaptive filter output. The proposed algorithm (that we call VSSSC after variable step size based on the squared cross-correlation was evaluated using white noise and speech signals.Simulation results show that our proposal achieves better performance than similar algorithms in single and double talk. The proposed algorithm can be used in a number of applications such as in echo reduction for long-haul voice communications.

  10. Visual evoked potential estimation by adaptive noise cancellation with neural-network-based fuzzy inference system.

    Science.gov (United States)

    Zeng, Y; Zhang, J; Yin, H; Pan, Y

    2007-01-01

    Visual evoked potentials (VEPs) are time-varying signals typically buried in relatively large background noise known as the electroencephalogram (EEG). In this paper, an adaptive noise cancellation with neural network-based fuzzy inference system (NNFIS) was used and the NNFIS was carefully designed to model the VEP signal. It is assumed that VEP responses can be modelled by NNFIS with the centres of its membership functions evenly distributed over time. The weights of NNFIS are adaptively determined by minimizing the variance of the error signal using the least mean squares (LMS) algorithm. As the NNFIS is dynamic to any change of VEP, the non-stationary characteristics of VEP can be tracked. Thus, this method should be able to track the VEP. Four sets of simulated data indicate that the proposed method is appropriate to estimate VEP. A total of 150 trials are processed to demonstrate the superior performance of the proposed method.

  11. Controlling kilometre-scale interferometric detectors for gravitational wave astronomy: Active phase noise cancellation using EOMs

    Energy Technology Data Exchange (ETDEWEB)

    Arnaud, N.; Balembois, L.; Bizouard, M.A.; Brisson, V. [LAL, Univ. Paris-Sud, IN2P3/CNRS, Univ. Paris-Saclay, Orsay (France); Casanueva, J., E-mail: casanuev@lal.in2p3.fr [LAL, Univ. Paris-Sud, IN2P3/CNRS, Univ. Paris-Saclay, Orsay (France); Cavalier, F.; Davier, M.; Frey, V.; Hello, P.; Huet, D.; Leroy, N. [LAL, Univ. Paris-Sud, IN2P3/CNRS, Univ. Paris-Saclay, Orsay (France); Loriette, V.; Maksimovic, I. [ESPCI, CNRS, F-75005 Paris (France); Robinet, F. [LAL, Univ. Paris-Sud, IN2P3/CNRS, Univ. Paris-Saclay, Orsay (France)

    2017-02-11

    The second generation of Gravitational waves detectors are kilometric Michelson interferometers with additional recycling Fabry–Perot cavities on the arms and ​the addition of two more recycling cavities to enhance their sensitivity, with the particularity that all the mirrors are suspended. In order to control them a new technique, based on the use of auxiliary lasers, has been developed to bring the interferometer to its working point, with all the cavities on their resonance, in an adiabatic way. The implementation of this technique in Advanced Virgo is under preparation and the propagation of a stable laser through a 3-km optical fibre is one of the most problematic issues. A new technique of active phase noise cancellation based on the use of Electro Optical Modulators has been developed, and a first prototype has been successfully tested.

  12. Application of Adaptive Noise Cancellation for Anti-Vibration in Yield Monitor

    Directory of Open Access Journals (Sweden)

    Yan LI

    2014-04-01

    Full Text Available In the process of grain harvest, yield monitor system acquires real-time spatial distribution information of crop yield to provide important basis of decision-making for subsequent assignments of precision agriculture. The measurement accuracy has been seriously affected by Combine working vibration. Based on an innovative test platform of wheat combine harvester for yield monitor, well simulate the working vibration at the field situation; impact-based grain flow sensor with the structure of dual-parallel-beams as test terminals and using the NI (National Instrument data acquisition card to acquire signals; grain impacted frequency as fundamental frequency to process harmonic extraction, and for extracted signals, applied the improved LMS adaptive algorithm to interference cancellation, aim to eliminate interference cased by working vibration. The comparative experiment show that the maximum relative error less than 2 % under the proposed method and proved that the proposed algorithm in this paper is effective.

  13. Greater Bone Fomation Induction Occurred in Aged Than Young Cancellous Bone Sites

    Science.gov (United States)

    Ke, H. Z.; Jee, Webster S. S.; Ito, H.; Setterberg, R. B.; Li, M.; Lin, B. Y.; Liang, X. G.; Ma, Y.F.

    1993-01-01

    We have determined the differences in the effects of continual prostaglandin E2 (PGE2) treatment in aged (non-growing) and young (growing) cancellous bone sites in 7 month-old Sprague-Dawley rats. The sites involved are the aged Distal Tibial Metaphysis (DTM) with a closed epiphysis and the young Proximal Tibial Metaphysis (PTM) with a slow growing, open epiphysis. The study involved rats treated with 0, 1, 3 or 6 mg PGE2/kg/d for 60, 120 and 180 days. Static and dynamic histomorphometty of percent trabecular area, and tissue-referent bone formation rate (BFR/TV) were determined in both DTM and PTM. In pretreatment controls, the secondary spongiosa of the two metaphyses contain the same amount of cancellous bone (11% in DTM vs. 13% in PTM), but markedly less bone formation in DTM (0.6%/y in DTM vs. 41.5%/y in PTM). After 60 days of 6 mg PGE2/kg/d treatment, %Tb.Ar was increased 607% in DTM and 199% in PTM, BFR/TV was increased to nearly 14 fold in DTM and only 5 fold in PTM. These results indicated the aged metaphysis of the DTM was much more responsive to PGE2 treatment than young, growing metaphysis of the PTM. The results of 120 and 180 days treatment did not significantly differ from 60 days treatment in both sites, indicating that the effect of continuous daily PGE2 treatment were in equilibrium after 60 days. We concluded that aged metaphysis was much more responsive to PGE2 treatment than young growing metaphysis.

  14. Greater Bone Formation Induction Occurred in Aged than Young Cancellous Bone Sites

    Science.gov (United States)

    Ke, H. Z.; Jee, W. S. S.; Ito, H.; Setterberg, R. B.; Li, M.; Lin, B. Y.; Liang, X. G.; Ma, Y. F.

    1993-01-01

    We have determined the differences in the effects of continual prostaglandin E(sub 2) (PGE(sub 2) treatment in aged (non-growing) and young (growing) cancellous bone sites in 7-month-old Sprague-Dawley rats. The sites involved are the aged distal tibial metaphysis (DTM) with a closed epiphysis and the young proximal tibial metaphysis (PTM) with a slow growing, open epiphysis. The study involved rats treated with 0, 1, 3 or 6 mg PGE(sub 2)/kg/d for 60, 120 and 180 days. Static and dynamic histomorphometry of percent trabecular area, and tissue-referent bone formation rate (BFR/TV) were determined in both DTM and PTM. In pretreatment controls, the secondary spongiosa of the two metaphyses contain the same amount of cancellous bone (11% in DTM vs. 13% in PTM), but markedly less bone formation in DTM (0.6%/y in DTM vs. 41.5%/y in PTM). After 60 days of 6 mg PGE(sub 2)/kg/d treatment, %Tb.Ar was increased 607% in DTM and 199% in PTM, BFR/TV was increased to nearly 14 fold in DTM and only 5 fold in PTM. These results indicated the aged metaphysis of the DTM was much more responsive to PGE(sub 2) treatment than young, growing metaphysis of the PTM. The results of 120 and 180 days treatment did not significantly differ from 60 days treatment in both sites, indicating that the effect of continuous daily PGE2 treatment were in equilibrium after 60 days. We concluded that aged metaphysis was much more responsive to PGE(sub 2) treatment than young growing metaphysis.

  15. Internal Fixation of Transverse Patella Fractures Using Cannulated Cancellous Screws with Anterior Tension Band Wiring

    Directory of Open Access Journals (Sweden)

    Khan I

    2016-07-01

    Full Text Available Aims: To evaluate the effectiveness and safety of anterior tension band wiring technique using two cannulated cancellous screws in patients with transverse (AO34-C1 or transverse with mildly comminuted (AO34-C2 patellar fractures. Materials and Methods: This is a prospective study of 25 patients with transverse fracture or transverse fracture with mildly comminuted patella fractures. All the patients were treated with open reduction and internal fixation using two parallel cannulated screws and 18G stainless steel wire as per the tension band principle. Results: There were eighteen males (72% and seven females (28%. The age group ranged from 24 to 58 years, with mean age of 38 years. The most common mode of injury was fall (72% followed by road traffic accident (20% and violent quadriceps contraction (8%. Transverse fracture was present in 60% and transverse fracture with mild comminution in 40% of patients. Mean time to achieve union was 10.7 weeks (range 8-12 weeks. Mean ROM at three months was 113.8 degree (90-130 and at final follow up this improved to 125.4 degrees (range 100-140. There was one case of knee stiffness and no case of implant failure was observed. Patients were evaluated using Bostman scoring, the mean score at three months being 26.04 which improved to 27.36 at the end of final follow up at one year. Conclusion: Cannulated cancellous screws with anterior tension band wiring is a safe, reliable and reproducible method in management of transverse patellar fractures, with less chances of implant failure and soft tissue irritation.

  16. Polyetheretherketone (PEEK) cage filled with cancellous allograft in anterior cervical discectomy and fusion

    Science.gov (United States)

    Liao, Jen-Chung; Chen, Wen-Jer; Chen, Lih-Huei

    2007-01-01

    From July 2004 to June 2005, 19 patients with 25 discs underwent anterior cervical discectomy and interbody fusion (ACDF) in which polyetheretherketone (PEEK) cages were filled with freeze-dried cancellous allograft bone. This kind of bone graft was made from femoral condyle that was harvested during total knee arthroplasty. Patient age at surgery was 52.9 (28–68) years. All patients were followed up at least 1 year. We measured the height of the disc and segmental sagittal angulation by pre-operative and post-operative radiographs. CT scan of the cervical spine at 1 year was used to evaluate fusion rates. Odom's criteria were used to assess the clinical outcome. All interbody disc spaces achieved successful union at 1-year follow-up. The use of a PEEK cage was found to increase the height of the disc immediately after surgery (5.0 mm pre-operatively, 7.3 mm immediately post-operatively). The final disc height was 6.2 mm, and the collapse of the disc height was 1.1 mm. The segmental lordosis also increased after surgery (2.0° pre-operatively, 6.6° immediately post-operatively), but the mean loss of lordosis correction was 3.3° at final follow-up. Seventy-four percent of patients (14/19) exhibited excellent/good clinical outcomes. Analysis of the results indicated the cancellous allograft bone-filled PEEK cage used in ACDF is a good choice for patients with cervical disc disease, and avoids the complications of harvesting iliac autograft. PMID:17639386

  17. Transform Domain Robust Variable Step Size Griffiths' Adaptive Algorithm for Noise Cancellation in ECG

    Science.gov (United States)

    Hegde, Veena; Deekshit, Ravishankar; Satyanarayana, P. S.

    2011-12-01

    The electrocardiogram (ECG) is widely used for diagnosis of heart diseases. Good quality of ECG is utilized by physicians for interpretation and identification of physiological and pathological phenomena. However, in real situations, ECG recordings are often corrupted by artifacts or noise. Noise severely limits the utility of the recorded ECG and thus needs to be removed, for better clinical evaluation. In the present paper a new noise cancellation technique is proposed for removal of random noise like muscle artifact from ECG signal. A transform domain robust variable step size Griffiths' LMS algorithm (TVGLMS) is proposed for noise cancellation. For the TVGLMS, the robust variable step size has been achieved by using the Griffiths' gradient which uses cross-correlation between the desired signal contaminated with observation or random noise and the input. The algorithm is discrete cosine transform (DCT) based and uses symmetric property of the signal to represent the signal in frequency domain with lesser number of frequency coefficients when compared to that of discrete Fourier transform (DFT). The algorithm is implemented for adaptive line enhancer (ALE) filter which extracts the ECG signal in a noisy environment using LMS filter adaptation. The proposed algorithm is found to have better convergence error/misadjustment when compared to that of ordinary transform domain LMS (TLMS) algorithm, both in the presence of white/colored observation noise. The reduction in convergence error achieved by the new algorithm with desired signal decomposition is found to be lower than that obtained without decomposition. The experimental results indicate that the proposed method is better than traditional adaptive filter using LMS algorithm in the aspects of retaining geometrical characteristics of ECG signal.

  18. Analysis of Acoustic Feedback/Echo Cancellation in Multiple-Microphone and Single-Loudspeaker Systems Using a Power Transfer Function Method

    DEFF Research Database (Denmark)

    Guo, Meng; Bo Elmedyb, Thomas; Jensen, Søren Holdt

    2011-01-01

    In this work, we analyze a general multiple-microphone and single-loudspeaker audio processing system, where a multichannel adaptive system is used to cancel the effect of acoustic feedback/echo, and a beamformer processes the feedback/echo canceled signals. We introduce and derive an accurate...... in the cancellation system: the least mean square, normalized least mean square, and the recursive least squares algorithms. Furthermore, we derive expressions to determine the step size parameter in the adaptive algorithms to achieve a desired system behavior, e.g., convergence rate at a specific frequency. Finally...

  19. Analysis of the effects of growth hormone, exercise and food restriction on cancellous bone in different bone sites in middle-aged female rats.

    Science.gov (United States)

    Banu, J; Orhii, P B; Okafor, M C; Wang, L; Kalu, D N

    2001-06-01

    The aim of this study is to determine the effects of growth hormone (GH), exercise (EX), GH+EX and food restriction on cancellous bone in middle-aged female rats. Female F344 rats aged 13 months were divided into (1) age-matched controls; (2) GH treated (2.5 mg/kg. 5 day/week); (3) EX (voluntary wheel running); (4) GH+EX; and (5) food restricted (FR) (fed 60% of the ad libitum food intake). The animals were treated for 18 weeks, at the end of which they were sacrificed. Cancellous bone and cortical bone in the fourth lumbar vertebra, proximal tibial metaphysis (PTM), distal femoral metaphysis (DFM) and femoral neck (NF) were analyzed using peripheral quantitative computerized tomography (pQCT) densitometry. Growth hormone increased cancellous bone area, cancellous bone mineral content, cortical bone area and cortical bone mineral content in the vertebra, PTM, DFM and NF. The tibial muscle wet weight was increased significantly after GH treatment. Exercise increased the cancellous bone area in the vertebra, PTM and DFM. Cortical bone area and cortical bone mineral content increased after EX in the vertebra, PTM, DFM and NF. No significant change was seen in the tibial muscle wet weight after EX. Growth hormone+EX increased cancellous bone area in the vertebra PTM and DFM but had no effect in neck of the femur. Cancellous bone mineral content, cortical bone area and cortical bone mineral content increased with GH+EX in the vertebra, PTM, DFM and NF. The tibial muscle wet weight was increased significantly with GH+EX. Food restriction decreased cancellous bone area and cancellous bone mineral content in all the bones studied. The decrease was statistically significant only at the distal femoral metaphysis. The tibial muscle wet weight decreased when compared with the age-matched control, but this decrease was not statistically significant. We conclude that the effect of the dose of GH used and the levels of voluntary wheel running EX used increased cancellous bone in

  20. EAM-based high-speed 100-km OFDM transmission featuring tolerant modulator operation enabled using SSII cancellation.

    Science.gov (United States)

    Chen, Hsing-Yu; Wei, Chia-Chien; Lu, I-Cheng; Chen, Yu-Chao; Chu, Hsuan-Hao; Chen, Jyehong

    2014-06-16

    In this study, a technique was developed to compensate for nonlinear distortion through cancelling subcarrier-to-subcarrier intermixing interference (SSII) in an electroabsorption modulator (EAM)-based orthogonal frequency-division multiplexing (OFDM) transmission system. The nonlinear distortion to be compensated for is induced by both EAM nonlinearity and fiber dispersion. Because an OFDM signal features an inherently high peak-to-average power ratio, a trade-off exists between the optical modulation index (OMI) and modulator nonlinearity. Therefore, the nonlinear distortion limits the operational tolerance of the bias voltage and the driving power to a small region. After applying the proposed SSII cancellation, the OMI of an OFDM signal was increased yielding only a small increment of nonlinear distortion, and the tolerance region of the operational conditions was also increased. By employing the proposed scheme, this study successfully demonstrates 50-Gbps OFDM transmission over 100-km dispersion-uncompensated single-mode fiber based on a single 10-GHz EAM.