Science.gov

Sample records for compressed work week

  1. Compressed Work Week (CWW) Request Form Name and Extension: Department

    E-print Network

    Van Den Eijnden, Eric

    Compressed Work Week (CWW) Request Form Name and Extension: Department: Supervisor's Name to continue existing CWW arrangement Compressed Work Week is not to exceed the parameters of a 4-day week: 9 Per Week Total Hours Per Week *This should be based on your normal 40 hour work week (which includes

  2. Impacts of compressed work week on vehicle trips and miles traveled. Final report

    SciTech Connect

    1994-10-01

    The project evaluates the effectiveness of compressed workweek (CWW) as a transportation control measure to reduce mobile source emissions. The project surveyed employees participating in CWW, or standard five-day forty-hour workweek. The survey collected employee characteristics and a seven-day travel diary. The analysis of the data shows that there is a great variability in weekly travel patterns among employees on CWW. Individual characteristics tend to dominate travel decisions compared to benefits of CWW. However, those on CWW reduce their overall weekly travel even when non-work trip increases are factored. The project reports that CWW can be an effective tool to improve air quality if it is implemented more widely in buisnesses that can integrate flexibility into their work schedules.

  3. 5 CFR 532.513 - Flexible and compressed work schedules.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 1 2013-01-01 2013-01-01 false Flexible and compressed work schedules... REGULATIONS PREVAILING RATE SYSTEMS Premium Pay and Differentials § 532.513 Flexible and compressed work schedules. Federal Wage System employees who are authorized to work flexible and compressed work...

  4. Factories : The Work in compressed Air (Prescribed Leaflet) Order, 1961 

    E-print Network

    Hare, John

    1961-01-01

    This Order prescribes the leaflet containing advice as to precautions to be taken in connection with work in compressed air which leaflet is to be supplied, in accordance with Regulation 16 of the Work in Compressed Air ...

  5. Compressed Air 101: Getting Compressed Air to Work 

    E-print Network

    Burke, J. J.; Bessey, E. G.

    2003-01-01

    plant energy use. Furthermore, air compression is inefficient with up to 95% of compressor power dissipated as heat. Thus even minor improvements in system operation, control strategies, and efficiency can yield large energy savings and significant non...

  6. 5 CFR 610.407 - Premium pay for holiday work for employees on compressed work schedules.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 false Premium pay for holiday work for employees on compressed work schedules. 610.407 Section 610.407 Administrative...REGULATIONS HOURS OF DUTY Flexible and Compressed Work Schedules § 610.407 Premium pay for...

  7. 5 CFR 610.407 - Premium pay for holiday work for employees on compressed work schedules.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 false Premium pay for holiday work for employees on compressed work schedules. 610.407 Section 610.407 Administrative...REGULATIONS HOURS OF DUTY Flexible and Compressed Work Schedules § 610.407 Premium pay for...

  8. 5 CFR 610.407 - Premium pay for holiday work for employees on compressed work schedules.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 false Premium pay for holiday work for employees on compressed work schedules. 610.407 Section 610.407 Administrative...REGULATIONS HOURS OF DUTY Flexible and Compressed Work Schedules § 610.407 Premium pay for...

  9. 5 CFR 610.407 - Premium pay for holiday work for employees on compressed work schedules.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 false Premium pay for holiday work for employees on compressed work schedules. 610.407 Section 610.407 Administrative...REGULATIONS HOURS OF DUTY Flexible and Compressed Work Schedules § 610.407 Premium pay for...

  10. 5 CFR 610.407 - Premium pay for holiday work for employees on compressed work schedules.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 false Premium pay for holiday work for employees on compressed work schedules. 610.407 Section 610.407 Administrative...REGULATIONS HOURS OF DUTY Flexible and Compressed Work Schedules § 610.407 Premium pay for...

  11. Working Characteristics of Variable Intake Valve in Compressed Air Engine

    PubMed Central

    Yu, Qihui; Shi, Yan; Cai, Maolin

    2014-01-01

    A new camless compressed air engine is proposed, which can make the compressed air energy reasonably distributed. Through analysis of the camless compressed air engine, a mathematical model of the working processes was set up. Using the software MATLAB/Simulink for simulation, the pressure, temperature, and air mass of the cylinder were obtained. In order to verify the accuracy of the mathematical model, the experiments were conducted. Moreover, performance analysis was introduced to design compressed air engine. Results show that, firstly, the simulation results have good consistency with the experimental results. Secondly, under different intake pressures, the highest output power is obtained when the crank speed reaches 500?rpm, which also provides the maximum output torque. Finally, higher energy utilization efficiency can be obtained at the lower speed, intake pressure, and valve duration angle. This research can refer to the design of the camless valve of compressed air engine. PMID:25379536

  12. Irreversible compressible work and APE dissipation in turbulent stratified fluids

    E-print Network

    Tailleux, Remi

    Irreversible compressible work and APE dissipation in turbulent stratified fluids R´emi Tailleux potential energy (APE) dissipation has remained until now a rather mysterious quantity, owing to the lack with a nonlinear equation of state that the APE dissipation is an irreversible energy conversion that dissipates

  13. One week work experience placements for GCSE or Sixth Form

    E-print Network

    Martin, Ralph R.

    sampling techniques · Improve background knowledge of specified animal and plant groups. Location: CampusOne week work experience placements for GCSE or Sixth Form students (ID:199) Outline Students spend, laboratory dissections of animals, use of microscopes and keys to identify species. Participants will conduct

  14. One week work experience placements for GCSE or Sixth Form

    E-print Network

    Martin, Ralph R.

    sampling techniques · Improve their background knowledge of specified animal and plant groups. LocationOne week work experience placements for GCSE or Sixth Form students (ID:199) Outline Students spend, laboratory dissections of animals, use of microscopes and keys to identify species. Participants will conduct

  15. Training for fitness: reconsidering the 80-hour work week.

    PubMed

    Caldicott, Catherine V; Holsapple, James W

    2008-01-01

    The medical literature is replete with articles about the Accreditation Council for Graduate Medical Education's 2003 resident duty hour restrictions. Most of these papers describe creative and thoughtful responses to the new system. However, others express concern that the "80-hour work week" could hamper continuity of care and educational activities. Nevertheless, if fatigue impairs resident learning and medical care quality, then work hour restrictions seem worthwhile. We add our voices to the critics' for additional reasons. Data support that fatigue occurs even with reasonable work schedules, and residents do not reliably use time off from work to rest. Regulated work schedules can interfere with adequate rehearsal of the physical and mental stamina required in certain specialties, yet patients have a right to expect their physicians to be trained in the particular demands of those specialties. Similarly, residents have a right to a realistic understanding of authentic clinical practice. Further, while self-sacrifice need not be routine, trainees should feel that occasional self-sacrifice is appropriate and acceptable for a physician. We reject uniform, arbitrary duty hour limits for all specialties. Rather, we propose that a subspecialty-based system can foster the development of the endurance, skills, and reasoning that patients and colleagues expect. PMID:18192772

  16. Effect of 3 Weeks Use of Compression Garments on Stride and Impact Shock during a Fatiguing Run.

    PubMed

    Lucas-Cuevas, A G; Priego-Quesada, J I; Aparicio, I; Giménez, J V; Llana-Belloch, S; Pérez-Soriano, P

    2015-09-01

    Excessive and prolonged exposure to impact acceleration during running is associated with increased injury rate. Acute use of compressive garments has been speculated to improve attenuation. However, it is unknown how longer interventions of compressive garments influence attenuation in running. 40 runners trained with compressive and placebo stockings for 3 weeks. Perception of comfort, stride parameters (rate, length) and impact acceleration (head and tibial peak acceleration, magnitude, acceleration rate and attenuation) were measured every 5?min during a fatigue run (30?min at 80% of the individual's maximal aerobic speed). Compressive stockings reduced tibial peak acceleration and magnitude compared to placebo stockings at every minute (p<0.05) except for the initial measurement (p>0.05). Moreover, compressive stockings led to a lower rate of increase in tibial peak acceleration (14%, p<0.005) and magnitude (16%, p<0.001) as a result of the development of fatigue compared to placebo stockings (24% and 26% increase, p=0.014 and p=0.003, respectively). Similar perception of comfort was reported for both garments. Training with compressive stockings for 3 weeks reduced impact acceleration and the rate of increase in acceleration compared to placebo stockings. These findings suggest that compressive stockings may play a protective role by reducing impact accelerations during running. PMID:26090880

  17. During the Internship: Students are required to work 8 hours per week, or 1 day per week, during the semester,

    E-print Network

    Oertel, Ulrich

    During the Internship: Students are required to work 8 hours per week, or 1 day per week, during of progress towards the educational goals of the internship proposal. The faculty supervisor will assign, and thoughtfulness and persistence in achieving learning objectives. At The Conclusion of the Internship: The student

  18. 29 CFR 1926.913 - Blasting in excavation work under compressed air.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 8 2013-07-01 2013-07-01 false Blasting in excavation work under compressed air. 1926.913... Use of Explosives § 1926.913 Blasting in excavation work under compressed air. (a) Detonators and... connecting wires are connected up. (b) When detonators or explosives are brought into an air lock,...

  19. 29 CFR 1926.913 - Blasting in excavation work under compressed air.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 8 2012-07-01 2012-07-01 false Blasting in excavation work under compressed air. 1926.913... Use of Explosives § 1926.913 Blasting in excavation work under compressed air. (a) Detonators and... connecting wires are connected up. (b) When detonators or explosives are brought into an air lock,...

  20. 29 CFR 1926.913 - Blasting in excavation work under compressed air.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Blasting in excavation work under compressed air. 1926.913... Use of Explosives § 1926.913 Blasting in excavation work under compressed air. (a) Detonators and... connecting wires are connected up. (b) When detonators or explosives are brought into an air lock,...

  1. 29 CFR 1926.913 - Blasting in excavation work under compressed air.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 8 2011-07-01 2011-07-01 false Blasting in excavation work under compressed air. 1926.913... Use of Explosives § 1926.913 Blasting in excavation work under compressed air. (a) Detonators and... connecting wires are connected up. (b) When detonators or explosives are brought into an air lock,...

  2. Compression in Visual Working Memory: Using Statistical Regularities to Form More Efficient Memory Representations

    E-print Network

    Oliva, Aude

    compressed fashion. Keywords: visual short-term memory, chunking, information theory, memory capacityCompression in Visual Working Memory: Using Statistical Regularities to Form More Efficient Memory University The information that individuals can hold in working memory is quite limited, but researchers have

  3. Giving 110%: A Portrait of a Michigan Teacher's Work Week. Policy Report Number 22

    ERIC Educational Resources Information Center

    Burian-Fitzgerald, Marisa; Harris, Debbi

    2004-01-01

    The vast majority of Michigan's teachers work above and beyond their required work week; the average teacher works more than 45 hours per week. The time teachers spend outside regular school hours is often ignored by critics who deride the "short hours and long vacations" enjoyed by teachers. When discussing compensation policies and changes to…

  4. Target compressions by working fluids driven with solid liner implosions

    NASA Technical Reports Server (NTRS)

    Chiang, P.-R.; Lewis, R. A.; Smith, G. A.; Dailey, J. M.; Chakrabarti, S.; Higman, K. I.; Bell, D.; Degnan, J. H.; Hussey, T. W.; Mullins, B. W.

    1994-01-01

    Compression by a spherical solid liner of a gold target surrounded by a hydrogen plasma is simulated. Two-dimensional simulations that treat only a subset of the physics included in the one-dimensional code were performed in an attempt to assess multidimensional effects. A one-dimensional numerical code has been developed to study the effects of thermal radiation and conduction. Results of pressure, density, and energy deposited for different initial plasma conditions are presented and discussed. Results from both one- and two-dimensional codes show that the average target density at peak compression is 39-43 g/cu cm, using the SHIVA Star facility at 90 kV discharge.

  5. Time Allocated During the Working Week to Pursue Environmental Initiatives: a Utopian Dream or Potential Reality? 

    E-print Network

    Ridley, Lucy

    This project investigates the opinions of members of staff at the University of Edinburgh concerning the role they believe environmental issues plays in their working week, and how this could be changed. Current relevant ...

  6. Balancing Work and Academics in College: Why Do Students Working 10 to 19 Hours Per Week Excel?

    ERIC Educational Resources Information Center

    Dundes, Lauren; Marx, Jeff

    2007-01-01

    Given that 74% of undergraduates work an average of 25.5 hours per week while going to school, we know surprisingly little about how off-campus employment affects undergraduates and to what extent its impact varies by the number of hours worked. Our survey of undergraduates at a small liberal arts college found that the academic performance of…

  7. 29 CFR 1926.913 - Blasting in excavation work under compressed air.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 8 2014-07-01 2014-07-01 false Blasting in excavation work under compressed air. 1926.913 Section 1926.913 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Blasting and the Use of Explosives § 1926.913 Blasting...

  8. Weekly working hours for Norwegian hospital doctors since 1994 with special attention to postgraduate training, work–home balance and the European Working Time Directive: a panel study

    PubMed Central

    Rosta, Judith; Aasland, Olaf G

    2014-01-01

    Objectives To examine the weekly working hours of Norwegian hospital doctors from 1994 to 2012 with special emphasis on the quality of postgraduate training and work–home balance, and in relation to the requirements of the European Working Time Directive (EWTD). Design Panel study based on postal questionnaires. Setting Norway. Participants Unbalanced cohort of 1300–1600 doctors in 1994, 1995, 1996, 1997, 2000, 2002, 2004, 2006, 2008, 2010 and 2012. Outcome measures Self-reported total weekly working hours and whether 45 weekly working hours are too short, sufficient, or too long to meet the quality requirements of obligatory postgraduate training for junior doctors. Results From 1994 to 2012, the number of weekly working hours was stable for senior (46–47?h) and junior (45–46?h) hospital doctors. In 2012, significantly more senior (27–35%) than junior (11–20%) doctors reported suboptimal work–home balance, defined as working more than 48?h a week. The majority perceived the present situation with an average of 45?h per week for juniors as sufficient for obligatory postgraduate specialist training, but doctors of higher age (OR 1.04, 95% CI 1.01 to 1.08), senior doctors (1.07, 1.04 to 1.11) and doctors working in surgical specialties (OR 1 vs laboratory medicine 0.03, 0.01 to 0.25, internal medicine 0.31, 0.17 to 0.58, psychiatry 0.12, 0.04 to 0.36, paediatrics 0.36, 0.12 to 1.07, anaesthesiology 0.08, 0.02 to 0.39, gynaecology 0.07, 0.01 to 0.56 and others 0.39, 0.04 to 3.56) were more likely to want the work-week to be longer. Conclusions The weekly working hours of Norwegian hospital doctors were always below the EWTD requirements. A significant growth of hospital doctor density over the past two decades, national regulations and cultural values might be important factors. Specialty differences in perception of sufficient training time may call for more flexibility in working time regulations. PMID:25311038

  9. On the work distribution for the adiabatic compression of a diluteclassical gas

    SciTech Connect

    Crooks, Gavin E.; Jarzynski, Christopher

    2006-02-23

    We consider the adiabatic and quasi-static compression of adilute classical gas, confined in a piston and initially equilibratedwith a heat bath. We find that the work performed during this process isdescribed statistically by a gamma distribution. We use this result toshow that the model satisfies the non-equilibrium work and fluctuationtheorems, but not the fluctation-dissipation relation. We discuss therare but dominant realizations that contribute most to the exponentialaverage of the work, and relate our results to potentially universal workdistributions.

  10. Mothers’ Health and Work-Related Factors at 11 Weeks Postpartum

    PubMed Central

    McGovern, Pat; Dowd, Bryan; Gjerdingen, Dwenda; Dagher, Rada; Ukestad, Laurie; McCaffrey, David; Lundberg, Ulf

    2007-01-01

    PURPOSE Many new mothers return to work soon after childbirth. This study examines personal and work-related factors associated with the postpartum health of employed women 11 weeks after childbirth. METHODS Using a prospective cohort design, we recruited 817 Minnesota mothers into the study while they were hospitalized for childbirth in 2001. Telephone interviews were conducted at 5 and 11 weeks postpartum. Eligible women were 18 years or older, employed, and spoke English and gave birth to a singleton infant. Multivariate models using instrumental variables (2-stage least squares) were used to estimate personal and employment characteristics associated with women’s physical and mental health and postpartum symptoms. RESULTS At 11 weeks postpartum, 661 participants (81% of enrollees) completed a full interview, and 50% of participants had returned to work. On average, women reported 4.1 (SD 3.2) childbirth-related symptoms, most frequently fatigue (43%). Factors significantly associated with better health outcomes included better preconception health, the absence of prenatal mood problems, more control over work and home activities, more social support at work and home, and less job stress. CONCLUSIONS The findings suggest postpartum women need to be evaluated regarding their fatigue levels and mental and physical symptoms. Women whose fatigue or postpartum symptoms limit daily role function may find it helpful to have health care clinicians counsel them on strategies to decrease job stress, increase social support at work and home, and certify their use of intermittent family and medical leave to help them manage their symptoms. PMID:18025489

  11. Irreversible compressible work and available potential energy dissipation in turbulent stratified fluids

    NASA Astrophysics Data System (ADS)

    Tailleux, Rémi

    2013-07-01

    Although it plays a key role in the theory of stratified turbulence, the concept of available potential energy (APE) dissipation has remained until now a rather mysterious quantity, owing to the lack of rigorous result about its irreversible character or energy conversion type. Here, we show by using rigorous energetics considerations rooted in the analysis of the Navier-Stokes for a fully compressible fluid with a nonlinear equation of state that the APE dissipation is an irreversible energy conversion that dissipates kinetic energy into internal energy, exactly as viscous dissipation. These results are established by showing that APE dissipation contributes to the irreversible production of entropy, and by showing that it is a part of the work of expansion/contraction. Our results provide a new interpretation of the entropy budget, that leads to a new exact definition of turbulent effective diffusivity, which generalizes the Osborn-Cox model, as well as a rigorous decomposition of the work of expansion/contraction into reversible and irreversible components. In the context of turbulent mixing associated with parallel shear flow instability, our results suggests that there is no irreversible transfer of horizontal momentum into vertical momentum, as seems to be required when compressible effects are neglected, with potential consequences for the parameterizations of momentum dissipation in the coarse-grained Navier-Stokes equations.

  12. The Department of Health’s “two week standard” for bowel cancer: is it working?

    PubMed Central

    Flashman, K; O’Leary, D P; Senapati, A; Thompson, M R

    2004-01-01

    Objective: To determine the effectiveness and efficiency of the Department of Health’s new general practitioner referral guidelines for bowel cancer. Design: One year prospective audit. Setting: District general hospital serving a population of 550 000. Subjects: All patients with bowel cancer; all patients referred on the basis of the two week standard and to a routine colorectal surgical outpatient clinic. Main outcome measures: Proportion of cancers referred on the basis of the two week standard and to other colorectal clinics; the proportion with the higher risk criteria and their diagnostic yields; stage of cancers diagnosed in outpatient clinics; and time to treatment. Results: A total of 249 cancers were diagnosed in the index year. Sixty five (26.1%) were referred to two week standard clinics, 40 (16.1%) to routine colorectal surgical outpatient clinics, 54 (22%) to other clinics, and 88 (35.3%) were emergencies. Thirteen patients per week were referred to the two week standard clinics and 85% (54/65) of cancers so referred were seen within two weeks. The diagnostic yield of cancer in the two week standard clinic was 9.4% (65/695) compared with 2.2% (40/1815) in the routine colorectal surgical outpatient clinic (p<0.0001). Eighty five per cent of patients with cancer referred to outpatients matched the guidelines for the two week standard clinics. Only 46% of this group were so referred. Overall, delay to treatment and Dukes’ stage were not improved in patients diagnosed in the two week standard clinics. Conclusions: Most patients with bowel cancer were not referred on the basis of the two week standard although most fulfilled the referral criteria, which had higher diagnostic yields. The two week standard clinics did not shorten the overall time to treatment or improve the stage of disease because the time lags before referral and after the outpatient appointment are the major causes of delay in the bowel cancer patient’s journey. PMID:14960522

  13. [Communication turned into prevention. The "European Week for the Safety and Health at Work": experience of the Italian Focal Point].

    PubMed

    Grosso, F; De Luca, C

    2006-01-01

    The constant focus on comprehensive quality of work and the promotion of an effective culture of prevention and communication, already indicated in the European Directives, gave new impetus to the strategy aimed at improving working conditions and workers' health. This study is aimed at identifying the successful factors of the European Week for Safety and Health at Work, an information and awareness campaign promoted by the European Agency for Safety and Health at Work based in Bilbao, through the analysis of the campaign's project and of the results achieved in Italy. The European Week, now at its 7th edition, represents a peerless opportunity to spread the culture of risk prevention and to raise awareness on the adoption of measures to improve workplaces, above all in small and medium enterprises. It is, furthermore, a valuable tool to communicate and disseminate messages and to promote good practices on occupational safety and health. ISPESL is the Italian Focal Point of the European Agency for Safety and Health at Work and has been supporting the organization of the European Week in Italy, since the first edition. It has been strongly committing itself to promote and disseminate information on the event, relying on its national network which operates throughout the national territory. The ISPESL web-site--http://www.ispesl.it--contains a web page dedicated to European Weeks, providing information on the campaign and on the related initiatives, on the materials, and on the main events taking place in Italy. PMID:16805473

  14. Molecular Lab Skills Bootcamp One Week Workshop; 0 Credit. Prerequisites: Commitment to work in a molecular research lab during

    E-print Network

    Hammack, Richard

    solutions, and molarity. We will work through a week long experiment cloning, isolating, and analyzing@vcu.edu Phone: 828-3598 Office: LFSCB 314 TAs: TBA Structure of course: May 11-15th 10-4pm LFSCB 207 and LFSCB

  15. Capitol Hill Recognizes National School Psychology Week and the Work of School Psychologists

    ERIC Educational Resources Information Center

    Communique, 2010

    2010-01-01

    In honor of National School Psychology Week, the NASP Government and Professional Relations (GPR) and Communications committees and NASP staff joined forces on a campaign to help elected officials on Capitol Hill learn about the positive contributions of school psychologists and how their services impact student mental health and learning. This…

  16. An old integration scheme for compressible flows revisited, refurbished and put to work

    NASA Technical Reports Server (NTRS)

    Moretti, G.

    1978-01-01

    A scheme for integrating the Euler equations of compressible flow in any hyperbolic case is presented. The scheme relies on the concept of characteristics but is strictly a finite difference scheme. Improvements in accuracy and physical consistence due to the scheme are discussed and results of its application to complex flows are shown.

  17. The 88-Hour Family: Effects of the 80-Hour Work Week on Marriage and Childbirth in a Surgical Residency

    PubMed Central

    Jones, Arden M; Jones, Kevin B

    2007-01-01

    The restriction of the resident physician work week to 80 hours has had dramatic affects on resident education and life-style. While effects on mood, psychological distress, and burn-out have been studied, the resultant changes in tangible quality of life have received little attention. birth rate was considered a measurable, relevant outcome. The resident marital and parental status by duty month was collected from a single orthopaedic surgical residency program for the four academic years preceding and following the implementation of the 80-hour work week. the number of births to residents during these periods were also tallied. The relative prevalence of positive marital status changed very little between residents in the two time durations from 66 to 71 percent, but parental status increased from 27 to 43 percent. The number of births per married resident duty year also increased from 0.23 pre-restrictions to 0.32 post-restrictions. While the individual decisions involved in generating these observed changes are complex and difficult to entirely decipher, it is thought that an increased perception of life-control within the work-hour restrictions may have prompted the dramatic changes in birth rate among resident families. PMID:17907445

  18. Compression in Visual Working Memory: Using Statistical Regularities to Form More Efficient Memory Representations

    ERIC Educational Resources Information Center

    Brady, Timothy F.; Konkle, Talia; Alvarez, George A.

    2009-01-01

    The information that individuals can hold in working memory is quite limited, but researchers have typically studied this capacity using simple objects or letter strings with no associations between them. However, in the real world there are strong associations and regularities in the input. In an information theoretic sense, regularities…

  19. Examining the Transition to a Four-Day School Week and Investigating Post-Change Faculty/Staff Work-Life Balance: A Community College Case Study

    ERIC Educational Resources Information Center

    Cardinale, Nelly

    2013-01-01

    This single descriptive embedded case study examined the process of implementing a four-day work/school week at a community college and investigated post-change faculty/staff work-life balance. All of the students attending this college live at home. The change was implemented due to state funding shortfalls, increasing college utility expenses…

  20. A Poll about Children and Weight: Crunch Time during the American Work and School Week--3 P.M. to Bed

    ERIC Educational Resources Information Center

    Robert Wood Johnson Foundation, 2013

    2013-01-01

    Childhood obesity is a major public health challenge today, with complex roots interwoven into nearly every facet of American life. This poll addresses one narrow slice of this web: the challenges that families face during the "crunch time" of the work and school week, between 3 pm and the time children go to bed. Compared to the school day, this…

  1. A Poll about Children and Weight: Crunch Time during the American Work and School Week--3 P.M. to Bed. Summary

    ERIC Educational Resources Information Center

    Robert Wood Johnson Foundation, 2013

    2013-01-01

    Childhood obesity is a major public health challenge today, with complex roots interwoven into nearly every facet of American life. This poll addresses one narrow slice of this web: the challenges that families face during the "crunch time" of the work and school week, between 3 p.m. and the time children go to bed. Compared to the school day,…

  2. Effects of 12-Week Bacopa monnieri Consumption on Attention, Cognitive Processing, Working Memory, and Functions of Both Cholinergic and Monoaminergic Systems in Healthy Elderly Volunteers.

    PubMed

    Peth-Nui, Tatimah; Wattanathorn, Jintanaporn; Muchimapura, Supaporn; Tong-Un, Terdthai; Piyavhatkul, Nawanant; Rangseekajee, Poonsri; Ingkaninan, Kornkanok; Vittaya-Areekul, Sakchai

    2012-01-01

    At present, the scientific evidence concerning the effect of Bacopa monnieri on brain activity together with working memory is less available. Therefore, we aimed to determine the effect of B. monnieri on attention, cognitive processing, working memory, and cholinergic and monoaminergic functions in healthy elderly. A randomized double-blind placebo-controlled design was utilized. Sixty healthy elderly subjects (mean age 62.62 years; SD 6.46), consisting of 23 males and 37 females, received either a standardized extract of B. monnieri (300 and 600?mg) or placebo once daily for 12 weeks. The cholinergic and monoaminergic systems functions were determined using AChE and MAO activities. Working memory was assessed using percent accuracy and reaction time of various memory tests as indices, whereas attention and cognitive processing were assessed using latencies and amplitude of N100 and P300 components of event-related potential. All assessments were performed before treatment, every four weeks throughout study period, and at four weeks after the cessation of intervention. B. monnieri-treated group showed improved working memory together with a decrease in both N100 and P300 latencies. The suppression of plasma AChE activity was also observed. These results suggest that B. monnieri can improve attention, cognitive processing, and working memory partly via the suppression of AChE activity. PMID:23320031

  3. Human Structure in Six and One-Half Weeks: One Approach to Providing Foundational Anatomical Competency in an Era of Compressed Medical School Anatomy Curricula

    ERIC Educational Resources Information Center

    Halliday, Nancy; O'Donoghue, Daniel; Klump, Kathryn E.; Thompson, Britta

    2015-01-01

    The University of Oklahoma College of Medicine reduced gross anatomy from a full semester, 130-hour course to a six and one-half week, 105-hour course as part of a new integrated systems-based pre-clinical curriculum. In addition to the reduction in contact hours, content from embryology, histology, and radiology were added into the course. The…

  4. Human Structure in Six and One-Half Weeks: One Approach to Providing Foundational Anatomical Competency in an Era of Compressed Medical School Anatomy curricula

    PubMed Central

    Halliday, Nancy; O'Donoghue, Daniel; Klump, Kathryn E; Thompson, Britta

    2015-01-01

    The University of Oklahoma College of Medicine reduced gross anatomy from a full semester, 130-hour course to a six and one-half week, 105-hour course as part of a new integrated systems-based pre-clinical curriculum. In addition to the reduction in contact hours, content from embryology, histology, and radiology were added into the course. The new curriculum incorporated best practices in the area of regular assessments, feedback, clinical application, multiple teaching modalities, and professionalism. A comparison of the components of the traditional and integrated curriculum, along with end of course evaluations and student performance revealed that the new curriculum was just as effective, if not more effective. This article also provides important lessons learned. Anat Sci Educ 8: 149–157. © 2014 The Authors. Published by Wiley Periodicals, Inc. on behalf of the American Association of Anatomists. PMID:24996159

  5. Patterns of external chest compression.

    PubMed

    Larsen, P D; Perrin, K; Galletly, D C

    2002-06-01

    We studied the performance of external chest compression by 20 fourth year medical students on 2 study days, separated by 5-7 weeks, 4-8 months after they had been initially trained in cardiopulmonary resuscitation (CPR). Our hypotheses were (1) that a given individual would perform external chest compressions in the same manner each time CPR was performed and (2) that the pattern of performance of chest compressions would be determined, in part, by the anthropometric characteristics of the rescuer. A Laerdal Skillmeter Resusci-Anne CPR manikin chest compression transducer was interfaced with an analogue-to-digital conversion board in a Macintosh LC III computer. Each subject on each study day performed four cycles of 15 compressions and two ventilations twice, once on a table (which raised the surface of the manikin sternum to 95 cm) and once on the floor. For each individual, on each attempt, we calculated the depth and rate of compressions, duty cycle, peak compression velocity, time to peak compression velocity and time to peak compression depth. In addition, we calculated the regression slope of compression depth versus compression number for each cycle of 15 chest compressions and over four cycles of compressions. Statistically significant correlations were observed between the first and second study days in each of the variables of chest compression measured, indicating that the performance of chest compressions was constant over time for a given individual. We observed that the depth of compression, duty cycle, time to peak compression, time to peak velocity and regression slope of depth of compressions versus compression number were significantly related to the height and weight of the rescuer. PMID:12062844

  6. Compression stockings

    MedlinePLUS

    Compression hose; Pressure stockings; Support stockings; Gradient stockings ... You wear compression stockings to improve blood flow in your legs. Compression stockings gently squeeze your legs to move blood up ...

  7. Compressed Sensing Off the Grid Gongguo Tang

    E-print Network

    Recht, Ben

    Compressed Sensing Off the Grid Gongguo Tang , Badri Narayan Bhaskar , Parikshit Shah of n regularly spaced samples. Unlike previous work in compressed sensing, the frequencies mismatch, compressed sensing, continuous dictionary, line spectral estimation, nuclear norm relaxation

  8. Marigat, Kenya In May of 2010, I was fortunate enough to travel to Marigat, Kenya for six weeks to work

    E-print Network

    wasn't working in the clinic, I spent a lot of time playing with the local children. The kids would meet us after school and we would play soccer, or sometimes just share stories about our families on my journey to becoming a physician. A group of mothers and children about to receive immunizations

  9. Doppler ultrasound surveillance in deep tunneling compressed-air work with Trimix breathing: bounce dive technique compared to saturation-excursion technique.

    PubMed

    Vellinga, T P van Rees; Sterk, W; de Boer, A G E M; van der Beek, A J; Verhoeven, A C; van Dijk, F J H

    2008-01-01

    The Western Scheldt Tunneling Project in The Netherlands provided a unique opportunity to evaluate two deep-diving techniques with Doppler ultrasound surveillance. Divers used the bounce diving techniques for repair and maintenance of the TBM. The tunnel boring machine jammed at its deepest depth. As a result the work time was not sufficient. The saturation diving technique was developed and permitted longer work time at great depth. Thirty-one divers were involved in this project. Twenty-three divers were examined using Doppler ultrasound. Data analysis addressed 52 exposures to Trimix at 4.6-4.8 bar gauge using the bounce technique and 354 exposures to Trimix at 4.0-6.9 bar gauge on saturation excursions. No decompression incidents occurred with either technique during the described phase of the project. Doppler ultrasound revealed that the bubble loads assessed in both techniques were generally low. We find out, that despite longer working hours, shorter decompression times and larger physical workloads, the saturation-excursion technique was associated with significant lower bubble grades than in the bounce technique using Doppler Ultrasound. We conclude that the saturation-excursion technique with Trimix is a good option for deep and long exposures in caisson work. The Doppler technique proved valuable, and it should be incorporated in future compressed-air work. PMID:19175196

  10. Compression of spinning plasma

    NASA Astrophysics Data System (ADS)

    Geyko, Vasily; Fisch, Nathaniel

    2014-10-01

    Adiabatic compression of a spinning plasma in cylindrical geometry is studied in thermodynamical limit. Compared to spinning neutral gas, additional electrostatic energy of charge separation yields to increased heat capacity for both axial and longitudinal compressions. Radial compression of plasma with external axial magnetic field is also considered. The obtained results can be used as thermodynamical estimations for z-pinch compression. This work was supported by DOE Contract No. DE-AC02-09CH11466, and by NNSA SSAA Grant No. DE-FG52-08NA28553.

  11. Short- and long-term effects of a 12-week intensive functional restoration programme in individuals work-disabled by chronic spinal pain.

    PubMed

    Ljungkvist, I

    2000-01-01

    The short- and long-term effects of a 12-week intensive functional restoration programme for 153 participants with chronic spinal pain are reported. The average patient sick leave before the programme started was about one year. At the 2-year follow-up, 69% of the participants reported in telephone interviews that they were working either part time or full time. Aerobic fitness, trunk muscle strength and lifting capacity increased during the programme. In the non-working groups, pain was rated higher and quality of life lower than in the working groups at the 1- and 2-year follow-ups. For the women's return to job, the best predictors were the time since the original pain onset and the achieved capacity to lift from waist to shoulder level. For the men's return to job, the best predictors were the initial work situation, the time since the original pain onset, the oxygen uptake and the lumbar lifting capacity at the end of the programme. The results of this non-controlled rehabilitation programme, both short- and long-term, support earlier findings that intensive rehabilitation can increase physical capacity and general well-being. PMID:10780049

  12. 29 CFR 1926.803 - Compressed air.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 8 2012-07-01 2012-07-01 false Compressed air. 1926.803 Section 1926.803 Labor Regulations... Compressed Air § 1926.803 Compressed air. (a) General provisions. (1) There shall be present, at all times... medical aspects of compressed air work and the treatment of decompression illness. He shall be...

  13. 29 CFR 1926.803 - Compressed air.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 8 2011-07-01 2011-07-01 false Compressed air. 1926.803 Section 1926.803 Labor Regulations... Compressed Air § 1926.803 Compressed air. (a) General provisions. (1) There shall be present, at all times... medical aspects of compressed air work and the treatment of decompression illness. He shall be...

  14. 29 CFR 1926.803 - Compressed air.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 8 2013-07-01 2013-07-01 false Compressed air. 1926.803 Section 1926.803 Labor Regulations... Compressed Air § 1926.803 Compressed air. (a) General provisions. (1) There shall be present, at all times... medical aspects of compressed air work and the treatment of decompression illness. He shall be...

  15. Modeling Compressed Turbulence

    SciTech Connect

    Israel, Daniel M.

    2012-07-13

    From ICE to ICF, the effect of mean compression or expansion is important for predicting the state of the turbulence. When developing combustion models, we would like to know the mix state of the reacting species. This involves density and concentration fluctuations. To date, research has focused on the effect of compression on the turbulent kinetic energy. The current work provides constraints to help development and calibration for models of species mixing effects in compressed turbulence. The Cambon, et al., re-scaling has been extended to buoyancy driven turbulence, including the fluctuating density, concentration, and temperature equations. The new scalings give us helpful constraints for developing and validating RANS turbulence models.

  16. Compression embedding

    DOEpatents

    Sandford, II, Maxwell T. (Los Alamos, NM); Handel, Theodore G. (Los Alamos, NM); Bradley, Jonathan N. (Los Alamos, NM)

    1998-01-01

    A method and apparatus for embedding auxiliary information into the digital representation of host data created by a lossy compression technique and a method and apparatus for constructing auxiliary data from the correspondence between values in a digital key-pair table with integer index values existing in a representation of host data created by a lossy compression technique. The methods apply to data compressed with algorithms based on series expansion, quantization to a finite number of symbols, and entropy coding. Lossy compression methods represent the original data as ordered sequences of blocks containing integer indices having redundancy and uncertainty of value by one unit, allowing indices which are adjacent in value to be manipulated to encode auxiliary data. Also included is a method to improve the efficiency of lossy compression algorithms by embedding white noise into the integer indices. Lossy compression methods use loss-less compression to reduce to the final size the intermediate representation as indices. The efficiency of the loss-less compression, known also as entropy coding compression, is increased by manipulating the indices at the intermediate stage. Manipulation of the intermediate representation improves lossy compression performance by 1 to 10%.

  17. Compression embedding

    DOEpatents

    Sandford, M.T. II; Handel, T.G.; Bradley, J.N.

    1998-07-07

    A method and apparatus for embedding auxiliary information into the digital representation of host data created by a lossy compression technique and a method and apparatus for constructing auxiliary data from the correspondence between values in a digital key-pair table with integer index values existing in a representation of host data created by a lossy compression technique are disclosed. The methods apply to data compressed with algorithms based on series expansion, quantization to a finite number of symbols, and entropy coding. Lossy compression methods represent the original data as ordered sequences of blocks containing integer indices having redundancy and uncertainty of value by one unit, allowing indices which are adjacent in value to be manipulated to encode auxiliary data. Also included is a method to improve the efficiency of lossy compression algorithms by embedding white noise into the integer indices. Lossy compression methods use loss-less compression to reduce to the final size the intermediate representation as indices. The efficiency of the loss-less compression, known also as entropy coding compression, is increased by manipulating the indices at the intermediate stage. Manipulation of the intermediate representation improves lossy compression performance by 1 to 10%. 21 figs.

  18. Compression embedding

    DOEpatents

    Sandford, II, Maxwell T. (Los Alamos, NM); Handel, Theodore G. (Los Alamos, NM); Bradley, Jonathan N. (Los Alamos, NM)

    1998-01-01

    A method of embedding auxiliary information into the digital representation of host data created by a lossy compression technique. The method applies to data compressed with lossy algorithms based on series expansion, quantization to a finite number of symbols, and entropy coding. Lossy compression methods represent the original data as integer indices having redundancy and uncertainty in value by one unit. Indices which are adjacent in value are manipulated to encode auxiliary data. By a substantially reverse process, the embedded auxiliary data can be retrieved easily by an authorized user. Lossy compression methods use loss-less compressions known also as entropy coding, to reduce to the final size the intermediate representation as indices. The efficiency of the compression entropy coding, known also as entropy coding is increased by manipulating the indices at the intermediate stage in the manner taught by the method.

  19. Compression embedding

    DOEpatents

    Sandford, M.T. II; Handel, T.G.; Bradley, J.N.

    1998-03-10

    A method of embedding auxiliary information into the digital representation of host data created by a lossy compression technique is disclosed. The method applies to data compressed with lossy algorithms based on series expansion, quantization to a finite number of symbols, and entropy coding. Lossy compression methods represent the original data as integer indices having redundancy and uncertainty in value by one unit. Indices which are adjacent in value are manipulated to encode auxiliary data. By a substantially reverse process, the embedded auxiliary data can be retrieved easily by an authorized user. Lossy compression methods use loss-less compressions known also as entropy coding, to reduce to the final size the intermediate representation as indices. The efficiency of the compression entropy coding, known also as entropy coding is increased by manipulating the indices at the intermediate stage in the manner taught by the method. 11 figs.

  20. Compression components.

    E-print Network

    Macdonald, Colin B.

    to music compression. 4 #12; An Audio Signal #15; 1-D signal. #15; \\CD quality" (44100 samples/sec, 16 bitsAPMA990 Final Project: Wavelets for Audio Compression Colin Macdonald 05/04/2002 Slides typeset of 2 J samples. 5 #12; 2 11 -Sample Block from Typical Audio Signal 200 400 600 800 1000 1200 1400 1600

  1. [Compressive therapy of lymphedema].

    PubMed

    Korpan, M I; Chekman, I S; Belova, O H; Fialka-Mozer, V

    2011-01-01

    Lymphedema is a simple complication after mastectomy. On current data there are two main methods of treatment of this disease that include different physical exercises, massage, compression of the edematous tissue and limb bandaging. One of this methods is based on the serial compression of the limb with an intermittent pump that is followed by physical exercises. Another method is known as the complex decongestive therapy (CDP) by Földi. Individual treatment program is worked out for each woman. The positive effect of treatment can be reached after a year of strict adherence to the program. PMID:22606885

  2. Astronomical context coder for image compression

    NASA Astrophysics Data System (ADS)

    Pata, Petr; Schindler, Jaromir

    2015-10-01

    Recent lossless still image compression formats are powerful tools for compression of all kind of common images (pictures, text, schemes, etc.). Generally, the performance of a compression algorithm depends on its ability to anticipate the image function of the processed image. In other words, a compression algorithm to be successful, it has to take perfectly the advantage of coded image properties. Astronomical data form a special class of images and they have, among general image properties, also some specific characteristics which are unique. If a new coder is able to correctly use the knowledge of these special properties it should lead to its superior performance on this specific class of images at least in terms of the compression ratio. In this work, the novel lossless astronomical image data compression method will be presented. The achievable compression ratio of this new coder will be compared to theoretical lossless compression limit and also to the recent compression standards of the astronomy and general multimedia.

  3. Video Compression

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Optivision developed two PC-compatible boards and associated software under a Goddard Space Flight Center Small Business Innovation Research grant for NASA applications in areas such as telerobotics, telesciences and spaceborne experimentation. From this technology, the company used its own funds to develop commercial products, the OPTIVideo MPEG Encoder and Decoder, which are used for realtime video compression and decompression. They are used in commercial applications including interactive video databases and video transmission. The encoder converts video source material to a compressed digital form that can be stored or transmitted, and the decoder decompresses bit streams to provide high quality playback.

  4. Information Compression

    E-print Network

    Roweis, Sam

    CSC310 -- Information Theory Sam Roweis Lecture 22: Lossy Compression & Rate­Distortion November 29 of di#erent frequency bands in audio but not the associated phases of sine waves. -- What di#erences do: If we want to penalize big errors less severely, we might consider the distortion d(a, b) = #a- b#. Rate

  5. Centrifugal Gas Compression Cycle

    NASA Astrophysics Data System (ADS)

    Fultun, Roy

    2002-11-01

    A centrifuged gas of kinetic, elastic hard spheres compresses isothermally and without flow of heat in a process that reverses free expansion. This theorem follows from stated assumptions via a collection of thought experiments, theorems and other supporting results, and it excludes application of the reversible mechanical adiabatic power law in this context. The existence of an isothermal adiabatic centrifugal compression process makes a three-process cycle possible using a fixed sample of the working gas. The three processes are: adiabatic mechanical expansion and cooling against a piston, isothermal adiabatic centrifugal compression back to the original volume, and isochoric temperature rise back to the original temperature due to an influx of heat. This cycle forms the basis for a Thomson perpetuum mobile that induces a loop of energy flow in an isolated system consisting of a heat bath connectable by a thermal path to the working gas, a mechanical extractor of the gas's internal energy, and a device that uses that mechanical energy and dissipates it as heat back into the heat bath. We present a simple experimental procedure to test the assertion that adiabatic centrifugal compression is isothermal. An energy budget for the cycle provides a criterion for breakeven in the conversion of heat to mechanical energy.

  6. 29 CFR 794.142 - Special compensation when overtime in excess of 12 daily or 56 weekly hours is worked in the...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...specified for exemption under section 7(b)(3) and works the following schedule: Hours M T W T F S S Tot. Worked 14 9 10 15 12 8 0 68 Number of overtime hours in excess of 56 in the workweek, 12; number of...

  7. 29 CFR 794.142 - Special compensation when overtime in excess of 12 daily or 56 weekly hours is worked in the...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...specified for exemption under section 7(b)(3) and works the following schedule: Hours M T W T F S S Tot. Worked 14 9 10 15 12 8 0 68 Number of overtime hours in excess of 56 in the workweek, 12; number of...

  8. 29 CFR 794.142 - Special compensation when overtime in excess of 12 daily or 56 weekly hours is worked in the...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...specified for exemption under section 7(b)(3) and works the following schedule: Hours M T W T F S S Tot. Worked 14 9 10 15 12 8 0 68 Number of overtime hours in excess of 56 in the workweek, 12; number of...

  9. 29 CFR 794.142 - Special compensation when overtime in excess of 12 daily or 56 weekly hours is worked in the...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...specified for exemption under section 7(b)(3) and works the following schedule: Hours M T W T F S S Tot. Worked 14 9 10 15 12 8 0 68 Number of overtime hours in excess of 56 in the workweek, 12; number of...

  10. 29 CFR 794.142 - Special compensation when overtime in excess of 12 daily or 56 weekly hours is worked in the...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...specified for exemption under section 7(b)(3) and works the following schedule: Hours M T W T F S S Tot. Worked 14 9 10 15 12 8 0 68 Number of overtime hours in excess of 56 in the workweek, 12; number of...

  11. An RIP-based approach to quantization for compressed sensing

    E-print Network

    Wardetzky, Max

    An RIP-based approach to quantization for compressed sensing Joe-Mei Feng and Felix Krahmer May 1 quantized compressed sensing measurements. Our method is based on the restricted isometry property (RIP Introduction 1.1 Compressed sensing Compressed sensing has drawn significant attention since the seminal works

  12. Tutorial on Compressed Sensing (or Compressive Sampling,

    E-print Network

    Reif, Rafael

    Tutorial on Compressed Sensing (or Compressive Sampling, or Linear Sketching) Piotr Indyk MIT #12 matrices: · Data stream algorithms · Coding theory (LDPCs) ­ Dense matrices: · Compressed sensing;Linear Compression · Setup: ­ Data/signal in n-dimensional space : x E.g., x is an 1000x1000 image n

  13. COMPRESSION WAVES AND PHASE PLOTS: SIMULATIONS

    SciTech Connect

    Orlikowski, D; Minich, R

    2011-08-01

    Compression wave analysis started nearly 50 years ago with Fowles. Coperthwaite and Williams gave a method that helps identify simple and steady waves. We have been developing a method that gives describes the non-isentropic character of compression waves, in general. One result of that work is a simple analysis tool. Our method helps clearly identify when a compression wave is a simple wave, a steady wave (shock), and when the compression wave is in transition. This affects the analysis of compression wave experiments and the resulting extraction of the high-pressure equation of state.

  14. Compressive sensing exploiting wavelet-domain dependencies for ECG compression

    NASA Astrophysics Data System (ADS)

    Polania, Luisa F.; Carrillo, Rafael E.; Blanco-Velasco, Manuel; Barner, Kenneth E.

    2012-06-01

    Compressive sensing (CS) is an emerging signal processing paradigm that enables sub-Nyquist sampling of sparse signals. Extensive previous work has exploited the sparse representation of ECG signals in compression applications. In this paper, we propose the use of wavelet domain dependencies to further reduce the number of samples in compressive sensing-based ECG compression while decreasing the computational complexity. R wave events manifest themselves as chains of large coefficients propagating across scales to form a connected subtree of the wavelet coefficient tree. We show that the incorporation of this connectedness as additional prior information into a modified version of the CoSaMP algorithm can significantly reduce the required number of samples to achieve good quality in the reconstruction. This approach also allows more control over the ECG signal reconstruction, in particular, the QRS complex, which is typically distorted when prior information is not included in the recovery. The compression algorithm was tested upon records selected from the MIT-BIH arrhythmia database. Simulation results show that the proposed algorithm leads to high compression ratios associated with low distortion levels relative to state-of-the-art compression algorithms.

  15. FRESCO: Referential compression of highly similar sequences.

    PubMed

    Wandelt, Sebastian; Leser, Ulf

    2013-01-01

    In many applications, sets of similar texts or sequences are of high importance. Prominent examples are revision histories of documents or genomic sequences. Modern high-throughput sequencing technologies are able to generate DNA sequences at an ever-increasing rate. In parallel to the decreasing experimental time and cost necessary to produce DNA sequences, computational requirements for analysis and storage of the sequences are steeply increasing. Compression is a key technology to deal with this challenge. Recently, referential compression schemes, storing only the differences between a to-be-compressed input and a known reference sequence, gained a lot of interest in this field. In this paper, we propose a general open-source framework to compress large amounts of biological sequence data called Framework for REferential Sequence COmpression (FRESCO). Our basic compression algorithm is shown to be one to two orders of magnitudes faster than comparable related work, while achieving similar compression ratios. We also propose several techniques to further increase compression ratios, while still retaining the advantage in speed: 1) selecting a good reference sequence; and 2) rewriting a reference sequence to allow for better compression. In addition,we propose a new way of further boosting the compression ratios by applying referential compression to already referentially compressed files (second-order compression). This technique allows for compression ratios way beyond state of the art, for instance,4,000:1 and higher for human genomes. We evaluate our algorithms on a large data set from three different species (more than 1,000 genomes, more than 3 TB) and on a collection of versions of Wikipedia pages. Our results show that real-time compression of highly similar sequences at high compression ratios is possible on modern hardware. PMID:24524158

  16. Maxwell's Demon and Data Compression

    E-print Network

    Hosoya, Akio; Shikano, Yutaka

    2011-01-01

    In an asymmetric Szilard engine model of Maxwell's demon, we show the equivalence between information theoretical and thermodynamic entropies when the demon erases information optimally. The work gain by the engine can be exactly canceled out by the work necessary to reset demon's memory after optimal data compression a la Shannon before the erasure.

  17. Efficient lossy compression for compressive sensing acquisition of images in compressive sensing imaging systems.

    PubMed

    Li, Xiangwei; Lan, Xuguang; Yang, Meng; Xue, Jianru; Zheng, Nanning

    2014-01-01

    Compressive Sensing Imaging (CSI) is a new framework for image acquisition, which enables the simultaneous acquisition and compression of a scene. Since the characteristics of Compressive Sensing (CS) acquisition are very different from traditional image acquisition, the general image compression solution may not work well. In this paper, we propose an efficient lossy compression solution for CS acquisition of images by considering the distinctive features of the CSI. First, we design an adaptive compressive sensing acquisition method for images according to the sampling rate, which could achieve better CS reconstruction quality for the acquired image. Second, we develop a universal quantization for the obtained CS measurements from CS acquisition without knowing any a priori information about the captured image. Finally, we apply these two methods in the CSI system for efficient lossy compression of CS acquisition. Simulation results demonstrate that the proposed solution improves the rate-distortion performance by 0.4~2 dB comparing with current state-of-the-art, while maintaining a low computational complexity. PMID:25490597

  18. 76 FR 57615 - National Health Information Technology Week, 2011

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-15

    ...Information Technology Week, 2011...Information Technology Week, 2011...President of the United States of America...the work of hospitals, private...Information Technology Week, we...care in the United States. Health...

  19. Compressing DNA sequence databases with coil

    PubMed Central

    White, W Timothy J; Hendy, Michael D

    2008-01-01

    Background Publicly available DNA sequence databases such as GenBank are large, and are growing at an exponential rate. The sheer volume of data being dealt with presents serious storage and data communications problems. Currently, sequence data is usually kept in large "flat files," which are then compressed using standard Lempel-Ziv (gzip) compression – an approach which rarely achieves good compression ratios. While much research has been done on compressing individual DNA sequences, surprisingly little has focused on the compression of entire databases of such sequences. In this study we introduce the sequence database compression software coil. Results We have designed and implemented a portable software package, coil, for compressing and decompressing DNA sequence databases based on the idea of edit-tree coding. coil is geared towards achieving high compression ratios at the expense of execution time and memory usage during compression – the compression time represents a "one-off investment" whose cost is quickly amortised if the resulting compressed file is transmitted many times. Decompression requires little memory and is extremely fast. We demonstrate a 5% improvement in compression ratio over state-of-the-art general-purpose compression tools for a large GenBank database file containing Expressed Sequence Tag (EST) data. Finally, coil can efficiently encode incremental additions to a sequence database. Conclusion coil presents a compelling alternative to conventional compression of flat files for the storage and distribution of DNA sequence databases having a narrow distribution of sequence lengths, such as EST data. Increasing compression levels for databases having a wide distribution of sequence lengths is a direction for future work. PMID:18489794

  20. A Hybrid ARQ Scheme for Resilient Packet Header Compression

    E-print Network

    Nosratinia, Aria

    A Hybrid ARQ Scheme for Resilient Packet Header Compression Vijay A Suryavanshi and Aria Nosratinia-mail: {vas021000, aria}@utdallas.edu Abstract-- In this work we address resilient packet header compression

  1. Turbulence in Compressible Flows

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Lecture notes for the AGARD Fluid Dynamics Panel (FDP) Special Course on 'Turbulence in Compressible Flows' have been assembled in this report. The following topics were covered: Compressible Turbulent Boundary Layers, Compressible Turbulent Free Shear Layers, Turbulent Combustion, DNS/LES and RANS Simulations of Compressible Turbulent Flows, and Case Studies of Applications of Turbulence Models in Aerospace.

  2. Compressive Sensing Collection Editors

    E-print Network

    Rowell, Eric C.

    Compressive Sensing Collection Editors: Mark A. Davenport Richard Baraniuk Ronald DeVore #12;#12;Compressive Sensing Collection Editors: Mark A. Davenport Richard Baraniuk Ronald DeVore Authors: Wai Lam Chan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 3 Compressive Sensing 3.1 Compressive Sensing

  3. Compression, restoration, resampling, ‘compressive sensing’: fast transforms in digital imaging

    NASA Astrophysics Data System (ADS)

    Yaroslavsky, L. P.

    2015-07-01

    Transform image processing methods are methods that work in domains of image transforms, such as discrete fourier, discrete cosine, wavelet and alike. They are the basic tools in image compression, image restoration, image resampling and geometrical transformations and can be traced back to the early 1970s. The paper presents a review of these methods with emphasis on their comparison and relationships, from the very first steps of transform image compression methods to adaptive and local adaptive transform domain filters for image restoration, to methods of precise image resampling and image reconstruction from sparse samples and up to the ‘compressive sensing’ approach that has gained popularity in the last few years. The review has a tutorial character and purpose.

  4. Extended testing of compression distillation.

    NASA Technical Reports Server (NTRS)

    Bambenek, R. A.; Nuccio, P. P.

    1972-01-01

    During the past eight years, the NASA Manned Spacecraft Center has supported the development of an integrated water and waste management system which includes the compression distillation process for recovering useable water from urine, urinal flush water, humidity condensate, commode flush water, and concentrated wash water. This paper describes the design of the compression distillation unit, developed for this system, and the testing performed to demonstrate its reliability and performance. In addition, this paper summarizes the work performed on pretreatment and post-treatment processes, to assure the recovery of sterile potable water from urine and treated urinal flush water.

  5. Compressive Video Classification for Decision Systems with Limited Resources

    E-print Network

    Tsakalides, Panagiotis

    Compressive Video Classification for Decision Systems with Limited Resources George Tzagkarakis}@ics.forth.gr Abstract--In this paper, we address the problem of video classification from a set of compressed features the problem of video classification by working directly in the compressed measurements domain. Among several

  6. Block based Method for Real-Time Compound Video Compression

    E-print Network

    Wu, Dapeng Oliver

    Block based Method for Real-Time Compound Video Compression Bing Hana, Dapeng Wua, and Huipin://www.wu.ece.ufl.edu ABSTRACT In this paper, we propose a novel compound video compression method for real-time applications of a single image. However, few works have addressed the problem of compound videos compression. Therefore, we

  7. One-step-ahead kinematic compressive sensing

    E-print Network

    Hover, Franz S.

    2013-04-24

    A large portion of work on compressive sampling and sensing has focused on reconstructions from a given measurement set. When the individual samples are expensive and optional, as is the case with autonomous agents operating ...

  8. Data compression using Chebyshev transform

    NASA Technical Reports Server (NTRS)

    Cheng, Andrew F. (Inventor); Hawkins, III, S. Edward (Inventor); Nguyen, Lillian (Inventor); Monaco, Christopher A. (Inventor); Seagrave, Gordon G. (Inventor)

    2007-01-01

    The present invention is a method, system, and computer program product for implementation of a capable, general purpose compression algorithm that can be engaged on the fly. This invention has particular practical application with time-series data, and more particularly, time-series data obtained form a spacecraft, or similar situations where cost, size and/or power limitations are prevalent, although it is not limited to such applications. It is also particularly applicable to the compression of serial data streams and works in one, two, or three dimensions. The original input data is approximated by Chebyshev polynomials, achieving very high compression ratios on serial data streams with minimal loss of scientific information.

  9. Population dynamics in compressible flows

    E-print Network

    Roberto Benzi; Mogens H. Jensen; David R. Nelson; Prasad Perlekar; Simone Pigolotti; Federico Toschi

    2012-03-28

    Organisms often grow, migrate and compete in liquid environments, as well as on solid surfaces. However, relatively little is known about what happens when competing species are mixed and compressed by fluid turbulence. In these lectures we review our recent work on population dynamics and population genetics in compressible velocity fields of one and two dimensions. We discuss why compressible turbulence is relevant for population dynamics in the ocean and we consider cases both where the velocity field is turbulent and when it is static. Furthermore, we investigate populations in terms of a continuos density field and when the populations are treated via discrete particles. In the last case we focus on the competition and fixation of one species compared to another

  10. Does Work Experience Actually Work?

    ERIC Educational Resources Information Center

    Field, John

    2012-01-01

    As unemployment levels rise, so education and training move into the policy spotlight. For the government, this is a very uncomfortable place to be right now. A number of large companies have withdrawn from the flagship Work Programme--under which jobseekers are invited to take up unpaid work placements of between two and eight weeks--amid…

  11. LAPPED TRANSFORMS COMPRESSION

    E-print Network

    de Queiroz, Ricardo L.

    will describe the principles of a block transform and its corresponding transform matrix along with its to compression applications. In Sec. 6.11, image compression systems are briefly introduced, including JPEG

  12. Sequential Compressed Sensing

    E-print Network

    Malioutov, Dmitry M.

    Compressed sensing allows perfect recovery of sparse signals (or signals sparse in some basis) using only a small number of random measurements. Existing results in compressed sensing literature have focused on characterizing ...

  13. Compressive sensing over networks

    E-print Network

    Medard, Muriel

    In this paper, we demonstrate some applications of compressive sensing over networks. We make a connection between compressive sensing and traditional information theoretic techniques in source coding and channel coding. ...

  14. Network functional compression

    E-print Network

    Feizi, Soheil (Feizi-Khankandi)

    2010-01-01

    In this thesis, we consider different aspects of the functional compression problem. In functional compression, the computation of a function (or, some functions) of sources is desired at the receiver(s). The rate region ...

  15. Compressed gas manifold

    DOEpatents

    Hildebrand, Richard J. (Edgemere, MD); Wozniak, John J. (Columbia, MD)

    2001-01-01

    A compressed gas storage cell interconnecting manifold including a thermally activated pressure relief device, a manual safety shut-off valve, and a port for connecting the compressed gas storage cells to a motor vehicle power source and to a refueling adapter. The manifold is mechanically and pneumatically connected to a compressed gas storage cell by a bolt including a gas passage therein.

  16. Secure Compressed Reading in Smart Grids

    E-print Network

    Cai, Sheng; Chen, Minghua; Yan, Jianxin; Jaggi, Sidharth

    2012-01-01

    Smart Grids measure energy usage in real-time and tailor supply and delivery accordingly, in order to improve power transmission and distribution. For the grids to operate effectively, it is critical to collect readings from massively-installed smart meters to control centers in an efficient and secure manner. In this paper, we propose a secure compressed reading scheme to address this critical issue. We observe that our collected real-world meter data express strong temporal correlations, indicating they are sparse in certain domains. We adopt Compressed Sensing technique to exploit this sparsity and design an efficient meter data transmission scheme. Our scheme achieves substantial efficiency offered by compressed sensing, without the need to know beforehand in which domain the meter data are sparse. This is in contrast to traditional compressed-sensing based scheme where such sparse-domain information is required a priori. We then design specific dependable scheme to work with our compressed sensing based ...

  17. REAL-TIME ADAPTIVE VIDEO COMPRESSION HAYDEN SCHAEFFER , YI YANG , HONGKAI ZHAO , AND STANLEY OSHER

    E-print Network

    Ferguson, Thomas S.

    REAL-TIME ADAPTIVE VIDEO COMPRESSION HAYDEN SCHAEFFER , YI YANG , HONGKAI ZHAO , AND STANLEY OSHER. In this work, we present an algorithm for predicting optimal real-time compression rates for video. The video the compressed frames. The adaptive video compression improves the quality of the reconstructed video (as

  18. Comparison of Artificial Compressibility Methods

    NASA Technical Reports Server (NTRS)

    Kiris, Cetin; Housman, Jeffrey; Kwak, Dochan

    2003-01-01

    Various artificial compressibility methods for calculating three-dimensional, steady and unsteady, laminar and turbulent, incompressible Navier-Stokes equations are compared in this work. Each method is described in detail along with appropriate physical and numerical boundary conditions. Analysis of well-posedness and numerical solutions to test problems for each method are provided. A comparison based on convergence behavior, accuracy, stability and robustness is used to establish the relative positive and negative characteristics of each method.

  19. Net Vet Weekly Week in Review

    E-print Network

    races a motorcycle and a car. He got Kristy interested in the sport and she drag races a 1973 Dodge Dart, hunting, fishing, roping and sports. Week Ahead: Shoppers Needed for Angel Tree The Stillwater Salvation Relations and Marketing. #12;

  20. Compressed Gas Safety for Experimental Fusion Facilities

    SciTech Connect

    Lee C. Cadwallader

    2004-09-01

    Experimental fusion facilities present a variety of hazards to the operators and staff. There are unique or specialized hazards, including magnetic fields, cryogens, radio frequency emissions, and vacuum reservoirs. There are also more general industrial hazards, such as a wide variety of electrical power, pressurized air, and cooling water systems in use, there are crane and hoist loads, working at height, and handling compressed gas cylinders. This paper outlines the projectile hazard assoicated with compressed gas cylinders and mthods of treatment to provide for compressed gas safety. This information should be of interest to personnel at both magnetic and inertial fusion experiments.

  1. Plasma heating by electric field compression.

    PubMed

    Avinash, K; Kaw, P K

    2014-05-01

    Plasma heating by compression of electric fields is proposed. It is shown that periodic cycles of external compression followed by the free expansion of electric fields in the plasma cause irreversible, collisionless plasma heating and corresponding entropy generation. As a demonstration of general ideas and scalings, the heating is shown in the case of a dusty plasma, where electric fields are created due to the presence of charged dust. The method is expected to work in the cases of compression of low frequency or dc electric fields created by other methods. Applications to high power laser heating of plasmas using this scheme are discussed. PMID:24856702

  2. 76 FR 28623 - Small Business Week, 2011

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-18

    ... United States of America the two hundred and thirty-fifth. (Presidential Sig.) [FR Doc. 2011-12307 Filed... Documents#0;#0; #0; #0;Title 3-- #0;The President ] Proclamation 8673 of May 12, 2011 Small Business Week... to work hard enough, you can succeed in our country. This week, we honor and celebrate...

  3. Saugus Iron Works Forge

    USGS Multimedia Gallery

    The Saugus Iron Works forge, which used a large hammer to compress the iron. Forging strenghened the iron, which, right out of the blast furnace, was brittle. The Saugus River, which powered the forge, can be seen in the background....

  4. Parallel image compression

    NASA Technical Reports Server (NTRS)

    Reif, John H.

    1987-01-01

    A parallel compression algorithm for the 16,384 processor MPP machine was developed. The serial version of the algorithm can be viewed as a combination of on-line dynamic lossless test compression techniques (which employ simple learning strategies) and vector quantization. These concepts are described. How these concepts are combined to form a new strategy for performing dynamic on-line lossy compression is discussed. Finally, the implementation of this algorithm in a massively parallel fashion on the MPP is discussed.

  5. Compressed Media: A New Dimension of Compressed Speech.

    ERIC Educational Resources Information Center

    Hartjen, Raymond H.

    Through the use of the Information Mapping and Information Blocking format, this paper discusses various means of increasing the information availability rate through compressed media. Techniques reviewed include: compressed speech, compressed media for individualization of instruction, compressed speech and remedial reading, speech compression

  6. Introduction to Data Compression What is Data Compression?

    E-print Network

    Razak, Saquib

    , and video · Examples: JPEG and MPEG · Lossy techniques usually achieve higher compression rates than, RAM, RP), AU, Vorbis, WMA, AIFF, WAVE, G.729a · Common video (sound and image) compression formatsIntroduction to Data Compression · What is Data Compression? · Why Data Compression? · How is Data

  7. Aerodynamics inside a rapid compression machine

    SciTech Connect

    Mittal, Gaurav; Sung, Chih-Jen

    2006-04-15

    The aerodynamics inside a rapid compression machine after the end of compression is investigated using planar laser-induced fluorescence (PLIF) of acetone. To study the effect of reaction chamber configuration on the resulting aerodynamics and temperature field, experiments are conducted and compared using a creviced piston and a flat piston under varying conditions. Results show that the flat piston design leads to significant mixing of the cold vortex with the hot core region, which causes alternate hot and cold regions inside the combustion chamber. At higher pressures, the effect of the vortex is reduced. The creviced piston head configuration is demonstrated to result in drastic reduction of the effect of the vortex. Experimental conditions are also simulated using the Star-CD computational fluid dynamics package. Computed results closely match with experimental observation. Numerical results indicate that with a flat piston design, gas velocity after compression is very high and the core region shrinks quickly due to rapid entrainment of cold gases. Whereas, for a creviced piston head design, gas velocity after compression is significantly lower and the core region remains unaffected for a long duration. As a consequence, for the flat piston, adiabatic core assumption can significantly overpredict the maximum temperature after the end of compression. For the creviced piston, the adiabatic core assumption is found to be valid even up to 100 ms after compression. This work therefore experimentally and numerically substantiates the importance of piston head design for achieving a homogeneous core region inside a rapid compression machine. (author)

  8. Compression needs change with market

    SciTech Connect

    Lyle, D.

    1997-07-01

    Gas movement has changed. Gathering has changed. Operators concentrate their best resources on the core business of producing natural gas. These factors have created changes in the way compression affects production. From the 1960s into the early 1990s, Knox Western, Ariel and Gemini left their imprints on the industry. They filled that significant market for small, multistage reciprocating compressors that moved the gas from the wellhead to the main pipelines that were the only customers for gas, says Arne A. Kellstrom of Kellstrom Associates, working with Knox Western Gas Compressors. They put together the less-than-200-horsepower reciprocating compressors that made up half the compression in the nation. Knox Western makes high-speed reciprocating compressors in a range from 25 to 1,400 horsepower.

  9. Compressed Air System Optimization 

    E-print Network

    Aegerter, R.

    1999-01-01

    air, the project's budget includes an air compressor that is amply sized. If this sounds like your plant or if your plant is having problems with sufficient compressed air capacity, then it may be time to optimize your compressed air system....

  10. Micromechanics of composite laminate compression failures

    NASA Technical Reports Server (NTRS)

    Guynn, E. Gail; Bradley, Walter L.

    1988-01-01

    The purpose of this annual progress report is to summarize the work effort and results accomplished from July 1987 through July 1988 on NASA Research Grant NAG1-659 entitled Micromechanics of Composite Laminate Compressive Failure. The report contains: (1) the objective of the proposed research, (2) the summary of accomplishments, (3) a more extensive review of compression literature, (4) the planned material (and corresponding properties) received to date, (5) the results for three possible specimen geometries, experimental procedures planned, and current status of the experiments, and (6) the work planned for the next contract year.

  11. Hello guys, this is the report on what we have done last week, putting to prot the visit of David the elder. Working by email is ne and ecient, but it is amazing how much

    E-print Network

    Nesvorny, David

    together....... In the past weeks, David the elder provided several computations that made us hope, he computed the spread in e and i as a function of time. He concluded that we can reproduce sooner or later spend some time in some resonance, thus acquireing some e and i. This process, however

  12. Hyperspectral Image Compression

    NASA Astrophysics Data System (ADS)

    Wright, Stephanie; Miguel, Agnieszka, , Dr.; Ashbach, Jason

    2008-05-01

    Hyperspectral images gathered by satellites or aerial means provide a vast amount of data for geophysicists. A few applications include the exploration of minerals, research of land pollution, and military surveillance. NASA and other agencies are producing gigabytes of hyperspectral images which need to be transmitted and stored daily. As these images require high compression rates and preservation of data integrity, we are presented with an intriguing compression problem. In our research we investigate two compression algorithms: a near-lossless technique based on minimizing maximum absolute distortion (MAD) and a lossy based algorithm which minimizes mean squared error (MSE). Near-lossless algorithms provide high compression rates and a uniform distribution of error. Whereas MSE based algorithms yield high compression rates but a non-uniform distribution of error. Our goal is to determine which algorithm yields high compression rates and minimal data loss without modifying post processing of hyperspectral data. In order to compare these two compression algorithms and determine their effect on post processing we used ENVI's image processing tools. We classified the decompressed images for each algorithm and compared them to the classified original image.

  13. Compressibility Effects in Aeronautical Engineering

    NASA Technical Reports Server (NTRS)

    Stack, John

    1941-01-01

    Compressible-flow research, while a relatively new field in aeronautics, is very old, dating back almost to the development of the first firearm. Over the last hundred years, researches have been conducted in the ballistics field, but these results have been of practically no use in aeronautical engineering because the phenomena that have been studied have been the more or less steady supersonic condition of flow. Some work that has been done in connection with steam turbines, particularly nozzle studies, has been of value, In general, however, understanding of compressible-flow phenomena has been very incomplete and permitted no real basis for the solution of aeronautical engineering problems in which.the flow is likely to be unsteady because regions of both subsonic and supersonic speeds may occur. In the early phases of the development of the airplane, speeds were so low that the effects of compressibility could be justifiably ignored. During the last war and immediately after, however, propellers exhibited losses in efficiency as the tip speeds approached the speed of sound, and the first experiments of an aeronautical nature were therefore conducted with propellers. Results of these experiments indicated serious losses of efficiency, but aeronautical engineers were not seriously concerned at the time became it was generally possible. to design propellers with quite low tip. speeds. With the development of new engines having increased power and rotational speeds, however, the problems became of increasing importance.

  14. Boson core compressibility

    NASA Astrophysics Data System (ADS)

    Khorramzadeh, Y.; Lin, Fei; Scarola, V. W.

    2012-04-01

    Strongly interacting atoms trapped in optical lattices can be used to explore phase diagrams of Hubbard models. Spatial inhomogeneity due to trapping typically obscures distinguishing observables. We propose that measures using boson double occupancy avoid trapping effects to reveal two key correlation functions. We define a boson core compressibility and core superfluid stiffness in terms of double occupancy. We use quantum Monte Carlo on the Bose-Hubbard model to empirically show that these quantities intrinsically eliminate edge effects to reveal correlations near the trap center. The boson core compressibility offers a generally applicable tool that can be used to experimentally map out phase transitions between compressible and incompressible states.

  15. 75 FR 10993 - Save Your Vision Week, 2010

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-10

    ...8483 of March 5, 2010 Save Your Vision Week, 2010 By the President of the United States...treatment of eye conditions. Save Your Vision Week is a time for all Americans to take action...performing household chores and yard work. This week, I encourage all Americans to visit...

  16. 75 FR 48853 - National Health Center Week, 2010

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-11

    ...Proclamation 8545--National Health Center Week, 2010 Presidential Documents Federal Register...August 5, 2010 National Health Center Week, 2010 By the President of the United States...preventive care. During National Health Center Week, we recognize the important work of...

  17. Compressed Sensing, Compressed Classification and Joint Signal Recovery

    E-print Network

    Marlin, Benjamin

    Compressed Sensing, Compressed Classification and Joint Signal Recovery Mohammad Emtiyaz Khan compressive sensing and its extension to classification and joint signal recovery. We present an overview of compressed sensing, followed by some simulation results on perfect reconstruction for sparse signals. We

  18. Lossless compression of instrumentation data. Final report

    SciTech Connect

    Stearns, S.D.

    1995-11-01

    This is our final report on Sandia National Laboratories Laboratory- Directed Research and Development (LDRD) project 3517.070. Its purpose has been to investigate lossless compression of digital waveform and image data, particularly the types of instrumentation data generated and processed at Sandia Labs. The three-year project period ran from October 1992 through September 1995. This report begins with a descriptive overview of data compression, with and without loss, followed by a summary of the activities on the Sandia project, including research at several universities and the development of waveform compression software. Persons who participated in the project are also listed. The next part of the report contains a general discussion of the principles of lossless compression. Two basic compression stages, decorrelation and entropy coding, are described and discussed. An example of seismic data compression is included. Finally, there is a bibliography of published research. Taken together, the published papers contain the details of most of the work and accomplishments on the project. This final report is primarily an overview, without the technical details and results found in the publications listed in the bibliography.

  19. Compression-sensitive magnetic resonance elastography

    NASA Astrophysics Data System (ADS)

    Hirsch, Sebastian; Beyer, Frauke; Guo, Jing; Papazoglou, Sebastian; Tzschaetzsch, Heiko; Braun, Juergen; Sack, Ingolf

    2013-08-01

    Magnetic resonance elastography (MRE) quantifies the shear modulus of biological tissue to detect disease. Complementary to the shear elastic properties of tissue, the compression modulus may be a clinically useful biomarker because it is sensitive to tissue pressure and poromechanical interactions. In this work, we analyze the capability of MRE to measure volumetric strain and the dynamic bulk modulus (P-wave modulus) at a harmonic drive frequency commonly used in shear-wave-based MRE. Gel phantoms with various densities were created by introducing CO2-filled cavities to establish a compressible effective medium. The dependence of the effective medium's bulk modulus on phantom density was investigated via static compression tests, which confirmed theoretical predictions. The P-wave modulus of three compressible phantoms was calculated from volumetric strain measured by 3D wave-field MRE at 50 Hz drive frequency. The results demonstrate the MRE-derived volumetric strain and P-wave modulus to be sensitive to the compression properties of effective media. Since the reconstruction of the P-wave modulus requires third-order derivatives, noise remains critical, and P-wave moduli are systematically underestimated. Focusing on relative changes in the effective bulk modulus of tissue, compression-sensitive MRE may be useful for the noninvasive detection of diseases involving pathological pressure alterations such as hepatic hypertension or hydrocephalus.

  20. The Kasabach-Merritt syndrome: treatment with intermittent pneumatic compression.

    PubMed Central

    Aylett, S E; Williams, A F; Bevan, D H; Holmes, S J

    1990-01-01

    A 6 week old infant presented with a giant angiomatous naevus of the leg complicated by chronic disseminated intravascular coagulation. The bleeding and laboratory abnormalities responded to intermittent pneumatic compression of the affected limb. This innocuous treatment should be considered in the Kasabach-Merritt syndrome. Images Figure 1 Figure 3 PMID:2386388

  1. Padding with Compressed Air 

    E-print Network

    Beals, C.

    2004-01-01

    We commonly find plants using padding to transport liquids or light solids short distances from tankers into storage tanks. Padding can wreck havoc in compressed air systems with limited storage, undersized cleanup equipment (dryers and filters...

  2. Compressive Optical Image Encryption

    NASA Astrophysics Data System (ADS)

    Li, Jun; Sheng Li, Jiao; Yang Pan, Yang; Li, Rong

    2015-05-01

    An optical image encryption technique based on compressive sensing using fully optical means has been proposed. An object image is first encrypted to a white-sense stationary noise pattern using a double random phase encoding (DRPE) method in a Mach-Zehnder interferometer. Then, the encrypted image is highly compressed to a signal using single-pixel compressive holographic imaging in the optical domain. At the receiving terminal, the encrypted image is reconstructed well via compressive sensing theory, and the original image can be decrypted with three reconstructed holograms and the correct keys. The numerical simulations show that the method is effective and suitable for optical image security transmission in future all-optical networks because of the ability of completely optical implementation and substantially smaller hologram data volume.

  3. Vertebral Compression Fractures

    MedlinePLUS

    ... OI: Information on Vertebral Compression Fractures 804 W. Diamond Ave., Ste. 210 Gaithersburg, MD 20878 (800) 981- ... osteogenesis imperfecta contact : Osteogenesis Imperfecta Foundation 804 W. Diamond Avenue, Suite 210, Gaithersburg, MD 20878 Tel: 800- ...

  4. Compressive Optical Image Encryption

    PubMed Central

    Li, Jun; Sheng Li, Jiao; Yang Pan, Yang; Li, Rong

    2015-01-01

    An optical image encryption technique based on compressive sensing using fully optical means has been proposed. An object image is first encrypted to a white-sense stationary noise pattern using a double random phase encoding (DRPE) method in a Mach-Zehnder interferometer. Then, the encrypted image is highly compressed to a signal using single-pixel compressive holographic imaging in the optical domain. At the receiving terminal, the encrypted image is reconstructed well via compressive sensing theory, and the original image can be decrypted with three reconstructed holograms and the correct keys. The numerical simulations show that the method is effective and suitable for optical image security transmission in future all-optical networks because of the ability of completely optical implementation and substantially smaller hologram data volume. PMID:25992946

  5. Image Data Compression

    NASA Astrophysics Data System (ADS)

    Kunt, Murat

    1988-03-01

    Image data compression is one of the oldest but still very active area of research in image processing. The digital representation of an image requires a very large number of bits. The goal of image data compression is to reduce this number, as much as possible, and reconstruct a faithful duplicate of the original picture. Early efforts in image coding, solely guided by information theory, led to a plethora of methods. The compression ratio reached a plateau around 10:1 a couple of years ago. Recent progress in the study of the brain mechanism of vision and scene analysis has opened new vistas in picture coding. Directional sensitivity of the neurones in the visual pathway combined with the separate processing of contours and textures has led to a new class of coding methods capable of achieving compression ratios as high as 100:1.

  6. Visualizing tension and compression

    NASA Astrophysics Data System (ADS)

    Taylor, Joseph A.

    2002-01-01

    The use of everyday materials to support instruction in statics is discussed. Specifically, materials such as cardboard and string are used to demonstrate tension and compression in truss-bridge models.

  7. Compressive optical image encryption.

    PubMed

    Li, Jun; Sheng Li, Jiao; Yang Pan, Yang; Li, Rong

    2015-01-01

    An optical image encryption technique based on compressive sensing using fully optical means has been proposed. An object image is first encrypted to a white-sense stationary noise pattern using a double random phase encoding (DRPE) method in a Mach-Zehnder interferometer. Then, the encrypted image is highly compressed to a signal using single-pixel compressive holographic imaging in the optical domain. At the receiving terminal, the encrypted image is reconstructed well via compressive sensing theory, and the original image can be decrypted with three reconstructed holograms and the correct keys. The numerical simulations show that the method is effective and suitable for optical image security transmission in future all-optical networks because of the ability of completely optical implementation and substantially smaller hologram data volume. PMID:25992946

  8. Focus on Compression Stockings

    MedlinePLUS

    ... down if it seems too long. • Try wearing rubber gloves, like those sold for household cleaning, or ... gloves made by the compression apparel companies. The rubber gloves make it easier to grip the material ...

  9. Consider Compressed Combustion 

    E-print Network

    Crowther, R. H.

    1982-01-01

    , and costs. In addition, overall advantages for applications involving energy sharing, such as cogeneration are even greater. Thus, compressed combustion should be considered seriously as an economical alternative to conventional heaters, especially in energy...

  10. The Compressibility Bubble

    NASA Technical Reports Server (NTRS)

    Stack, John

    1935-01-01

    Simultaneous air-flow photographs and pressure-distribution measurements have been made of the NACA 4412 airfoil at high speeds in order to determine the physical nature of the compressibility bubble. The flow photographs were obtained by the Schlieren method and the pressures were simultaneously measured for 54 stations on the 5-inch-chord wing by means of a multiple-tube photographic manometer. Pressure-measurement results and typical Schlieren photographs are presented. The general nature of the phenomenon called the "compressibility bubble" is shown by these experiments. The source of the increased drag is the compression shock that occurs, the excess drag being due to the conversion of a considerable amount of the air-stream kinetic energy into heat at the compression shock.

  11. High-performance compression of astronomical images

    NASA Technical Reports Server (NTRS)

    White, Richard L.

    1993-01-01

    Astronomical images have some rather unusual characteristics that make many existing image compression techniques either ineffective or inapplicable. A typical image consists of a nearly flat background sprinkled with point sources and occasional extended sources. The images are often noisy, so that lossless compression does not work very well; furthermore, the images are usually subjected to stringent quantitative analysis, so any lossy compression method must be proven not to discard useful information, but must instead discard only the noise. Finally, the images can be extremely large. For example, the Space Telescope Science Institute has digitized photographic plates covering the entire sky, generating 1500 images each having 14000 x 14000 16-bit pixels. Several astronomical groups are now constructing cameras with mosaics of large CCD's (each 2048 x 2048 or larger); these instruments will be used in projects that generate data at a rate exceeding 100 MBytes every 5 minutes for many years. An effective technique for image compression may be based on the H-transform (Fritze et al. 1977). The method that we have developed can be used for either lossless or lossy compression. The digitized sky survey images can be compressed by at least a factor of 10 with no noticeable losses in the astrometric and photometric properties of the compressed images. The method has been designed to be computationally efficient: compression or decompression of a 512 x 512 image requires only 4 seconds on a Sun SPARCstation 1. The algorithm uses only integer arithmetic, so it is completely reversible in its lossless mode, and it could easily be implemented in hardware for space applications.

  12. Smoothing DCT Compression Artifacts

    NASA Technical Reports Server (NTRS)

    Ahumada, A. J., Jr.; Horng, R.; Statler, Irving C. (Technical Monitor)

    1994-01-01

    Image compression based on quantizing the image in the discrete cosine transform (DCT) domain can generate blocky artifacts in the output image. It is possible to reduce these artifacts and RMS error by adjusting measures of block edginess and image roughness, while restricting the DCT coefficient values to values that would have been quantized to those of the compressed image. We also introduce a DCT coefficient amplitude adjustment that reduces RMS error.

  13. Compressed Sensing in Astronomy

    E-print Network

    J. Bobin; J-L Starck; R. Ottensamer

    2008-02-01

    Recent advances in signal processing have focused on the use of sparse representations in various applications. A new field of interest based on sparsity has recently emerged: compressed sensing. This theory is a new sampling framework that provides an alternative to the well-known Shannon sampling theory. In this paper we investigate how compressed sensing (CS) can provide new insights into astronomical data compression and more generally how it paves the way for new conceptions in astronomical remote sensing. We first give a brief overview of the compressed sensing theory which provides very simple coding process with low computational cost, thus favoring its use for real-time applications often found on board space mission. We introduce a practical and effective recovery algorithm for decoding compressed data. In astronomy, physical prior information is often crucial for devising effective signal processing methods. We particularly point out that a CS-based compression scheme is flexible enough to account for such information. In this context, compressed sensing is a new framework in which data acquisition and data processing are merged. We show also that CS provides a new fantastic way to handle multiple observations of the same field view, allowing us to recover information at very low signal-to-noise ratio, which is impossible with standard compression methods. This CS data fusion concept could lead to an elegant and effective way to solve the problem ESA is faced with, for the transmission to the earth of the data collected by PACS, one of the instruments on board the Herschel spacecraft which will be launched in 2008.

  14. Detail of interior of compressed air chamber showing top of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail of interior of compressed air chamber showing top of working chamber and tie rods that strengthen the outer shell plates of the compression chamber. - Sub Marine Explorer, Located along the beach of Isla San Telmo, Pearl Islands, Isla San Telmo, Former Panama Canal Zone, CZ

  15. PROPOSAL FOR LOW-FREQUENCY, HIGH-POWER PULSE COMPRESSION

    E-print Network

    McDonald, Kirk

    PROPOSAL FOR LOW-FREQUENCY, HIGH-POWER PULSE COMPRESSION BY A THYRATRON SWITCH Y. Zhao, BNL (April: Thyratrons usually work at video frequency, but brief operation at RF frequency is possible before breakdown occurs. POWER COMPRESSION RATIO: Reduced by leakage in the switch and by transmission loss. Theoretical

  16. Image compression technique

    DOEpatents

    Fu, Chi-Yung (San Francisco, CA); Petrich, Loren I. (Livermore, CA)

    1997-01-01

    An image is compressed by identifying edge pixels of the image; creating a filled edge array of pixels each of the pixels in the filled edge array which corresponds to an edge pixel having a value equal to the value of a pixel of the image array selected in response to the edge pixel, and each of the pixels in the filled edge array which does not correspond to an edge pixel having a value which is a weighted average of the values of surrounding pixels in the filled edge array which do correspond to edge pixels; and subtracting the filled edge array from the image array to create a difference array. The edge file and the difference array are then separately compressed and transmitted or stored. The original image is later reconstructed by creating a preliminary array in response to the received edge file, and adding the preliminary array to the received difference array. Filling is accomplished by solving Laplace's equation using a multi-grid technique. Contour and difference file coding techniques also are described. The techniques can be used in a method for processing a plurality of images by selecting a respective compression approach for each image, compressing each of the images according to the compression approach selected, and transmitting each of the images as compressed, in correspondence with an indication of the approach selected for the image.

  17. Image compression technique

    DOEpatents

    Fu, C.Y.; Petrich, L.I.

    1997-03-25

    An image is compressed by identifying edge pixels of the image; creating a filled edge array of pixels each of the pixels in the filled edge array which corresponds to an edge pixel having a value equal to the value of a pixel of the image array selected in response to the edge pixel, and each of the pixels in the filled edge array which does not correspond to an edge pixel having a value which is a weighted average of the values of surrounding pixels in the filled edge array which do correspond to edge pixels; and subtracting the filled edge array from the image array to create a difference array. The edge file and the difference array are then separately compressed and transmitted or stored. The original image is later reconstructed by creating a preliminary array in response to the received edge file, and adding the preliminary array to the received difference array. Filling is accomplished by solving Laplace`s equation using a multi-grid technique. Contour and difference file coding techniques also are described. The techniques can be used in a method for processing a plurality of images by selecting a respective compression approach for each image, compressing each of the images according to the compression approach selected, and transmitting each of the images as compressed, in correspondence with an indication of the approach selected for the image. 16 figs.

  18. Compressed Sensing: Decoding and Quantization

    E-print Network

    Fournier, John J.F.

    Compressed Sensing: Decoding and Quantization by Rayan Saab B.E., American University of Beirut of these developments were spurred by the emerging area of compressed sensing. Compressed sensing is a signal, we first address the theoretical properties of p, a class of compressed sensing decoders that rely

  19. MotorWeek

    SciTech Connect

    2009-01-01

    In 2008, PBS's MotorWeek, television's original automotive magazine, visited Argonne's Transportation Technology R&D Center "to learn what it really takes to make clean power sources a viable reality."

  20. MotorWeek

    ScienceCinema

    None

    2013-04-19

    In 2008, PBS's MotorWeek, television's original automotive magazine, visited Argonne's Transportation Technology R&D Center "to learn what it really takes to make clean power sources a viable reality."

  1. Structure and Properties of Silica Glass Densified in Cold Compression and Hot Compression

    NASA Astrophysics Data System (ADS)

    Guerette, Michael; Ackerson, Michael R.; Thomas, Jay; Yuan, Fenglin; Bruce Watson, E.; Walker, David; Huang, Liping

    2015-10-01

    Silica glass has been shown in numerous studies to possess significant capacity for permanent densification under pressure at different temperatures to form high density amorphous (HDA) silica. However, it is unknown to what extent the processes leading to irreversible densification of silica glass in cold-compression at room temperature and in hot-compression (e.g., near glass transition temperature) are common in nature. In this work, a hot-compression technique was used to quench silica glass from high temperature (1100?°C) and high pressure (up to 8?GPa) conditions, which leads to density increase of ~25% and Young’s modulus increase of ~71% relative to that of pristine silica glass at ambient conditions. Our experiments and molecular dynamics (MD) simulations provide solid evidences that the intermediate-range order of the hot-compressed HDA silica is distinct from that of the counterpart cold-compressed at room temperature. This explains the much higher thermal and mechanical stability of the former than the latter upon heating and compression as revealed in our in-situ Brillouin light scattering (BLS) experiments. Our studies demonstrate the limitation of the resulting density as a structural indicator of polyamorphism, and point out the importance of temperature during compression in order to fundamentally understand HDA silica.

  2. Structure and Properties of Silica Glass Densified in Cold Compression and Hot Compression

    PubMed Central

    Guerette, Michael; Ackerson, Michael R.; Thomas, Jay; Yuan, Fenglin; Bruce Watson, E.; Walker, David; Huang, Liping

    2015-01-01

    Silica glass has been shown in numerous studies to possess significant capacity for permanent densification under pressure at different temperatures to form high density amorphous (HDA) silica. However, it is unknown to what extent the processes leading to irreversible densification of silica glass in cold-compression at room temperature and in hot-compression (e.g., near glass transition temperature) are common in nature. In this work, a hot-compression technique was used to quench silica glass from high temperature (1100?°C) and high pressure (up to 8?GPa) conditions, which leads to density increase of ~25% and Young’s modulus increase of ~71% relative to that of pristine silica glass at ambient conditions. Our experiments and molecular dynamics (MD) simulations provide solid evidences that the intermediate-range order of the hot-compressed HDA silica is distinct from that of the counterpart cold-compressed at room temperature. This explains the much higher thermal and mechanical stability of the former than the latter upon heating and compression as revealed in our in-situ Brillouin light scattering (BLS) experiments. Our studies demonstrate the limitation of the resulting density as a structural indicator of polyamorphism, and point out the importance of temperature during compression in order to fundamentally understand HDA silica. PMID:26469314

  3. Compressibility and Density Fluctuations in Molecular-Cloud Turbulence

    E-print Network

    Pan, Liubin; Haugbolle, Troels; Nordlund, Aake

    2015-01-01

    The compressibility of molecular cloud (MC) turbulence plays a crucial role in star formation models, because it controls the amplitude and distribution of density fluctuations. The relation between the compressive ratio (the ratio of powers in compressive and solenoidal motions) and the statistics of turbulence has been studied systematically only in idealized simulations with random external forces. In this work, we analyze a simulation of large-scale turbulence(250 pc) driven by supernova (SN) explosions that has been shown to yield realistic MC properties. We demonstrate that SN driving results in MC turbulence that is only mildly compressive, with the turbulent ratio of compressive to solenoidal modes ~0.3 on average, lower than the equilibrium value of 0.5 found in the inertial range of isothermal simulations with random solenoidal driving. We also find that the compressibility of the turbulence is not noticeably affected by gravity, nor is the mean cloud expansion or contraction velocity (MCs do not co...

  4. Curriculum Characteristics of Time-Compressed Course in a U.S. Higher Education Institution

    ERIC Educational Resources Information Center

    Hyun, Eunsook; Kretovics, Mark; Crowe, Alicia

    2006-01-01

    The study explored characteristics of the curriculum practice of higher education faculty in the context of time-compressed (e.g., 5-6 weeks) courses as compared with regular term (15-16 weeks) courses. The researchers used open-ended questions on a web-based survey at a large doctoral-extensive university in a Midwestern state in the United…

  5. Data compression of stereopairs

    NASA Technical Reports Server (NTRS)

    Perkins, Michael G.

    1992-01-01

    This paper addresses the problem of stereopair data compression. Two fundamentally different techniques for compressing stereopairs are discussed. The first technique, called disparity-compensated transform-domain predictive coding, attempts to minimize the mean-square error between the original stereopair and the compressed stereopair. The second technique, called mixed-resolution coding, is a psychophysically justified technique that exploits known facts about human stereovision to code stereopairs in a subjectively acceptable manner. A method for assessing the quality of compressed stereopairs is also presented. It involves measuring the ability of an observer to perceive depth in coded stereopairs. It is found that observers generally perceived objects to be further away in compressed stereopairs than they did in originals. Finally, the problem of coding stereopairs is considered from a rate-distortion perspective. It is proved that the rate distortion limit for coding stereopairs cannot in general be achieved by a coder that first codes and decodes the right picture sequence independently of the left picture sequence, and then codes and decodes the left picture sequence given the decoded right picture sequence.

  6. Locating barcodes using JPEG 2000 compressed data

    NASA Astrophysics Data System (ADS)

    Feng, Xiaojun; Gormish, Michael J.

    2005-07-01

    In this paper, a novel method is proposed to locate one-dimensional barcodes in JPEG 2000 images. The barcode locating system consists of two parts: candidate barcode location detection, barcode location verification and refinement. Both parts are designed to work in the compressed domain of JPEG 2000 images. The locations of candidate barcodes are extracted from the header data and verified by examining part of the decoded coefficients of the JPEG 2000 file. Since only a small amount of the compressed data is used, this algorithm has a low complexity relative to algorithms which use all of the pixel data.

  7. Unsteady Aerodynamics - Subsonic Compressible Inviscid Case

    NASA Technical Reports Server (NTRS)

    Balakrishnan, A. V.

    1999-01-01

    This paper presents a new analytical treatment of Unsteady Aerodynamics - the linear theory covering the subsonic compressible (inviscid) case - drawing on some recent work in Operator Theory and Functional Analysis. The specific new results are: (a) An existence and uniqueness proof for the Laplace transform version of the Possio integral equation as well as a new closed form solution approximation thereof. (b) A new representation for the time-domain solution of the subsonic compressible aerodynamic equations emphasizing in particular the role of the initial conditions.

  8. Preprototype Vapor Compression Distillation Subsystem development

    NASA Technical Reports Server (NTRS)

    Thompson, C. D.; Ellis, G. S.; Schubert, F. H.

    1981-01-01

    Vapor Compression Distillation (VCD) has evolved as the most promising approach to reclaim potable water from wastewater for future long-term manned space missions. Life Systems, Inc. (LSI), working with NASA, has developed a preprototype Vapor Compression Distillation Subsystem (VCDS) which processes wastewater at 1.4 kg/h. The preprototype unit weighs 143 kg, occupies a volume of 0.47 cu m, and will reclaim 96 percent of the available wastewater. This unit has been tested by LSI and is scheduled for further testing at NASA-JSC. This paper presents the preprototype VCDS design, configuration, performance data, test results and flight system projections.

  9. Variable Quality Compression of Fluid Dynamical Data Sets Using a 3D DCT Technique

    NASA Astrophysics Data System (ADS)

    Loddoch, A.; Schmalzl, J.

    2005-12-01

    In this work we present a data compression scheme that is especially suited for the compression of data sets resulting from computational fluid dynamics (CFD). By adopting the concept of the JPEG compression standard and extending the approach of Schmalzl (Schmalzl, J. Using standard image compression algorithms to store data from computational fluid dynamics. Computers and Geosciences, 29, 10211031, 2003) we employ a three-dimensional discrete cosine transform of the data. The resulting frequency components are rearranged, quantized and finally stored using Huffman-encoding and standard variable length integer codes. The compression ratio and also the introduced loss of accuracy can be adjusted by means of two compression parameters to give the desired compression profile. Using the proposed technique compression ratios of more than 60:1 are possible with an mean error of the compressed data of less than 0.1%.

  10. Compression failure of angle-ply laminates

    NASA Technical Reports Server (NTRS)

    Peel, Larry D.; Hyer, Michael W.; Shuart, Mark J.

    1991-01-01

    The present work deals with modes and mechanisms of failure in compression of angle-ply laminates. Experimental results were obtained from 42 angle-ply IM7/8551-7a specimens with a lay-up of ((plus or minus theta)/(plus or minus theta)) sub 6s where theta, the off-axis angle, ranged from 0 degrees to 90 degrees. The results showed four failure modes, these modes being a function of off-axis angle. Failure modes include fiber compression, inplane transverse tension, inplane shear, and inplane transverse compression. Excessive interlaminar shear strain was also considered as an important mode of failure. At low off-axis angles, experimentally observed values were considerably lower than published strengths. It was determined that laminate imperfections in the form of layer waviness could be a major factor in reducing compression strength. Previously developed linear buckling and geometrically nonlinear theories were used, with modifications and enhancements, to examine the influence of layer waviness on compression response. The wavy layer is described by a wave amplitude and a wave length. Linear elastic stress-strain response is assumed. The geometrically nonlinear theory, in conjunction with the maximum stress failure criterion, was used to predict compression failure and failure modes for the angle-ply laminates. A range of wave length and amplitudes were used. It was found that for 0 less than or equal to theta less than or equal to 15 degrees failure was most likely due to fiber compression. For 15 degrees less than theta less than or equal to 35 degrees, failure was most likely due to inplane transverse tension. For 35 degrees less than theta less than or equal to 70 degrees, failure was most likely due to inplane shear. For theta less than 70 degrees, failure was most likely due to inplane transverse compression. The fiber compression and transverse tension failure modes depended more heavily on wave length than on wave amplitude. Thus using a single parameter, such as a ratio of wave amplitude to wave length, to describe waviness in a laminate would be inaccurate. Throughout, results for AS4/3502, studied previously, are included for comparison. At low off-axis angles, the AS4/3502 material system was found to be less sensitive to layer waviness than IM7/8551-7a. Analytical predictions were also obtained for laminates with waviness in only some of the layers. For this type of waviness, laminate compression strength could also be considered a function of which layers in the laminate were wavy, and where those wavy layers were. Overall, the geometrically nonlinear model correlates well with experimental results.

  11. COMPRESSED-AIR ENERGY STORAGE SYSTEMS FOR STAND-ALONE OFF-GRID PHOTOVOLTAIC MODULES

    E-print Network

    Deymier, Pierre

    COMPRESSED-AIR ENERGY STORAGE SYSTEMS FOR STAND-ALONE OFF-GRID PHOTOVOLTAIC MODULES Dominique, USA ABSTRACT In this work, a low-cost, low-volume, low-maintenance, small-scale compressed-air energy-storage materials, flywheels, pumped hydro (PH), superconducting magnetic energy storage (SMES) and compressed air

  12. Extracting Constitutive Stress-Strain Behavior of Microscopic Phases by Micropillar Compression

    SciTech Connect

    Williams, J. J.; Walters, Jennifer; Wang, Mingyue; Chawla, N.; Rohatgi, Aashish

    2013-02-01

    The manuscript describes how micropillar compression technique can be used to perform uniaxial compression tests within individual grains so as to generate local-scale constitutive behavior which, otherwise cannot be ascertained from the conventional macroscale compression test techniques. The manuscript uses steel and magnesium alloys as an example. A portion of the magnesium work was performed at PNNL.

  13. Display Pre-filtering for Multi-view Video Compression Matthias Zwicker

    E-print Network

    Suresh, Subra

    Display Pre-filtering for Multi-view Video Compression Matthias Zwicker University of California for this approach. In this paper, we present a frame- work for efficient compression of multi-view video streams a large number of pixels to achieve high image quality. Therefore, data compression is a major is- sue

  14. Compressed domain video indexing techniques using DCT and motion vector information in MPEG video \\Lambda

    E-print Network

    Lin, King-Ip "David"

    Compressed domain video indexing techniques using DCT and motion vector information in MPEG video, and retrieval techniques. Given that video is typically stored efficiently in a compressed format, if we can and operating at the pixel level. Compressed domain parsing of video has been presented in earlier work where

  15. Compression of VQM Features for Low Bit-Rate Video Quality Monitoring

    E-print Network

    Girod, Bernd

    Compression of VQM Features for Low Bit-Rate Video Quality Monitoring Mina Makar, Yao-Chung Lin. In this paper, we propose a method to efficiently compress standardized VQM (Video Quality Model) [1] features work [3]­ [5] proposed sending compressed features of the original video and using them to obtain

  16. Master's Thesis, Next Generation Video Compression www.ericsson.com/careers

    E-print Network

    Schön, Thomas

    Master's Thesis, Next Generation Video Compression www.ericsson.com/careers About Us At Ericsson we and standardization of next generation video compression and media delivery technology. We work in teams of highly information and exploiting redundant information in the video data, in order to facilitate high compression

  17. TO APPEAR IN IEEE TRANSACTIONS ON SIGNAL PROCESSING 1 Robust 1-bit Compressive Sensing using Adaptive

    E-print Network

    Ferguson, Thomas S.

    TO APPEAR IN IEEE TRANSACTIONS ON SIGNAL PROCESSING 1 Robust 1-bit Compressive Sensing using Adaptive Outlier Pursuit Ming Yan, Yi Yang and Stanley Osher Abstract--In compressive sensing (CS. There are many algorithms proposed for 1- bit compressive sensing and they work well when there is no noise

  18. Blind compressive sensing dynamic MRI Sajan Goud Lingala, Student Member, IEEE,

    E-print Network

    Jacob, Mathews

    1 Blind compressive sensing dynamic MRI Sajan Goud Lingala, Student Member, IEEE, Mathews Jacob, Senior Member, IEEE Abstract We propose a novel blind compressive sensing (BCS) frame work to recover to classical compressed sensing, the BCS scheme simultaneously estimates the dictionary and the sparse

  19. Compressive Sensing with Unknown Parameters Marco Rossi(), Alexander M. Haimovich(), and Yonina C. Eldar()

    E-print Network

    Eldar, Yonina

    Compressive Sensing with Unknown Parameters Marco Rossi(), Alexander M. Haimovich(), and Yonina C.m.haimovich}@njit.edu, yonina@ee.technion.ac.il Abstract--This work addresses target detection from a set of compressive sensing localization using compressive sensing in the spatial domain, i.e., the use of an undersampled MIMO radar array

  20. Isentropic Compression of Argon

    SciTech Connect

    H. Oona; J.C. Solem; L.R. Veeser, C.A. Ekdahl; P.J. Rodriquez; S.M. Younger; W. Lewis; W.D. Turley

    1997-08-01

    We are studying the transition of argon from an insulator to a conductor by compressing the frozen gas isentropically to pressures at which neighboring atomic orbitals overlap sufficiently to allow some electron motion between atoms. Argon and the other rare gases have closed electron shells and therefore remain montomic, even when they solidify. Their simple structure makes it likely that any measured change in conductivity is due to changes in the atomic structure, not in molecular configuration. As the crystal is compressed the band gap closes, allowing increased conductivity. We have begun research to determine the conductivity at high pressures, and it is our intention to determine the compression at which the crystal becomes a metal.

  1. Compressible Flow Toolbox

    NASA Technical Reports Server (NTRS)

    Melcher, Kevin J.

    2006-01-01

    The Compressible Flow Toolbox is primarily a MATLAB-language implementation of a set of algorithms that solve approximately 280 linear and nonlinear classical equations for compressible flow. The toolbox is useful for analysis of one-dimensional steady flow with either constant entropy, friction, heat transfer, or Mach number greater than 1. The toolbox also contains algorithms for comparing and validating the equation-solving algorithms against solutions previously published in open literature. The classical equations solved by the Compressible Flow Toolbox are as follows: The isentropic-flow equations, The Fanno flow equations (pertaining to flow of an ideal gas in a pipe with friction), The Rayleigh flow equations (pertaining to frictionless flow of an ideal gas, with heat transfer, in a pipe of constant cross section), The normal-shock equations, The oblique-shock equations, and The expansion equations.

  2. The compressible mixing layer

    NASA Technical Reports Server (NTRS)

    Vandromme, Dany; Haminh, Hieu

    1991-01-01

    The capability of turbulence modeling correctly to handle natural unsteadiness appearing in compressible turbulent flows is investigated. Physical aspects linked to the unsteadiness problem and the role of various flow parameters are analyzed. It is found that unsteady turbulent flows can be simulated by dividing these motions into an 'organized' part for which equations of motion are solved and a remaining 'incoherent' part represented by a turbulence model. Two-equation turbulence models and second-order turbulence models can yield reasonable results. For specific compressible unsteady turbulent flow, graphic presentations of different quantities may reveal complementary physical features. Strong compression zones are observed in rapid flow parts but shocklets do not yet occur.

  3. Microseismic source imaging in a compressed domain

    NASA Astrophysics Data System (ADS)

    Vera Rodriguez, Ismael; Sacchi, Mauricio D.

    2014-08-01

    Microseismic monitoring is an essential tool for the characterization of hydraulic fractures. Fast estimation of the parameters that define a microseismic event is relevant to understand and control fracture development. The amount of data contained in the microseismic records however, poses a challenge for fast continuous detection and evaluation of the microseismic source parameters. Work inspired by the emerging field of Compressive Sensing has showed that it is possible to evaluate source parameters in a compressed domain, thereby reducing processing time. This technique performs well in scenarios where the amplitudes of the signal are above the noise level, as is often the case in microseismic monitoring using downhole tools. This paper extends the idea of the compressed domain processing to scenarios of microseismic monitoring using surface arrays, where the signal amplitudes are commonly at the same level as, or below, the noise amplitudes. To achieve this, we resort to the use of an imaging operator, which has previously been found to produce better results in detection and location of microseismic events from surface arrays. The operator in our method is formed by full-waveform elastodynamic Green's functions that are band-limited by a source time function and represented in the frequency domain. Where full-waveform Green's functions are not available, ray tracing can also be used to compute the required Green's functions. Additionally, we introduce the concept of the compressed inverse, which derives directly from the compression of the migration operator using a random matrix. The described methodology reduces processing time at a cost of introducing distortions into the results. However, the amount of distortion can be managed by controlling the level of compression applied to the operator. Numerical experiments using synthetic and real data demonstrate the reductions in processing time that can be achieved and exemplify the process of selecting the compression rate that produces a tolerable amount of distortion into the results.

  4. Compressive Temporal Higher Order Cyclostationary Statistics

    NASA Astrophysics Data System (ADS)

    Lim, Chia Wei; Wakin, Michael B.

    2015-06-01

    The application of nonlinear transformations to a cyclostationary signal for the purpose of revealing hidden periodicities has proven to be useful for applications requiring signal selectivity and noise tolerance. The fact that the hidden periodicities, referred to as cyclic moments, are often compressible in the Fourier domain motivates the use of compressive sensing (CS) as an efficient acquisition protocol for capturing such signals. In this work, we consider the class of Temporal Higher Order Cyclostationary Statistics (THOCS) estimators when CS is used to acquire the cyclostationary signal assuming compressible cyclic moments in the Fourier domain. We develop a theoretical framework for estimating THOCS using the low-rate nonuniform sampling protocol from CS and illustrate the performance of this framework using simulated data.

  5. Envera Variable Compression Ratio Engine

    SciTech Connect

    Charles Mendler

    2011-03-15

    Aggressive engine downsizing, variable compression ratio and use of the Atkinson cycle are being combined to improve fuel economy by up to 40 percent relative to port fuel injected gasoline engines, while maintaining full engine power. Approach Engine downsizing is viewed by US and foreign automobile manufacturers as one of the best options for improving fuel economy. While this strategy has already demonstrated a degree of success, downsizing and fuel economy gains are currently limited. With new variable compression ratio technology however, the degree of engine downsizing and fuel economy improvement can be greatly increased. A small variable compression ratio (VCR) engine has the potential to return significantly higher vehicle fuel economy while also providing high power. Affordability and potential for near term commercialization are key attributes of the Envera VCR engine. VCR Technology To meet torque and power requirements, a smaller engine needs to do more work per stroke. This is typically accomplished by boosting the incoming charge with either a turbo or supercharger so that more energy is present in the cylinder per stroke to do the work. With current production engines the degree of engine boosting (which correlates to downsizing) is limited by detonation (combustion knock) at high boost levels. Additionally, the turbo or supercharger needs to be responsive and efficient while providing the needed boost. VCR technology eliminates the limitation of engine knock at high load levels by reducing compression ratio to {approx}9:1 (or whatever level is appropriate) when high boost pressures are needed. By reducing the compression ratio during high load demand periods there is increased volume in the cylinder at top dead center (TDC) which allows more charge (or energy) to be present in the cylinder without increasing the peak pressure. Cylinder pressure is thus kept below the level at which the engine would begin to knock. When loads on the engine are low the compression ratio can be raised (to as much as 18:1) providing high engine efficiency. It is important to recognize that for a well designed VCR engine cylinder pressure does not need to be higher than found in current production turbocharged engines. As such, there is no need for a stronger crankcase, bearings and other load bearing parts within the VCR engine. The Envera VCR mechanism uses an eccentric carrier approach to adjust engine compression ratio. The crankshaft main bearings are mounted in this eccentric carrier or 'crankshaft cradle' and pivoting the eccentric carrier 30 degrees adjusts compression ratio from 9:1 to 18:1. The eccentric carrier is made up of a casting that provides rigid support for the main bearings, and removable upper bearing caps. Oil feed to the main bearings transits through the bearing cap fastener sockets. The eccentric carrier design was chosen for its low cost and rigid support of the main bearings. A control shaft and connecting links are used to pivot the eccentric carrier. The control shaft mechanism features compression ratio lock-up at minimum and maximum compression ratio settings. The control shaft method of pivoting the eccentric carrier was selected due to its lock-up capability. The control shaft can be rotated by a hydraulic actuator or an electric motor. The engine shown in Figures 3 and 4 has a hydraulic actuator that was developed under the current program. In-line 4-cylinder engines are significantly less expensive than V engines because an entire cylinder head can be eliminated. The cost savings from eliminating cylinders and an entire cylinder head will notably offset the added cost of the VCR and supercharging. Replacing V6 and V8 engines with in-line VCR 4-cylinder engines will provide high fuel economy at low cost. Numerous enabling technologies exist which have the potential to increase engine efficiency. The greatest efficiency gains are realized when the right combination of advanced and new technologies are packaged together to provide the greatest gains at the least cost. Aggressive engine downsiz

  6. Isentropic compression of argon

    SciTech Connect

    Veeser, L.R.; Ekdahl, C.A.; Oona, H.

    1997-06-01

    The compression was done in an MC-1 flux compression (explosive) generator, in order to study the transition from an insulator to a conductor. Since conductivity signals were observed in all the experiments (except when the probe is removed), both the Teflon and the argon are becoming conductive. The conductivity could not be determined (Teflon insulation properties unknown), but it could be bounded as being {sigma}=1/{rho}{le}8({Omega}cm){sub -1}, because when the Teflon breaks down, the dielectric constant is reduced. The Teflon insulator problem remains, and other ways to better insulate the probe or to measure the conductivity without a probe is being sought.

  7. On Compressible Vortex Sheets

    NASA Astrophysics Data System (ADS)

    Secchi, Paolo

    2005-05-01

    We introduce the main known results of the theory of incompressible and compressible vortex sheets. Moreover, we present recent results obtained by the author with J. F. Coulombel about supersonic compressible vortex sheets in two space dimensions. The problem is a nonlinear free boundary hyperbolic problem with two difficulties: the free boundary is characteristic and the Lopatinski condition holds only in a weak sense, yielding losses of derivatives. Under a supersonic condition that precludes violent instabilities, we prove an energy estimate for the boundary value problem obtained by linearization around an unsteady piecewise solution.

  8. Data compression for sequencing data

    PubMed Central

    2013-01-01

    Post-Sanger sequencing methods produce tons of data, and there is a general agreement that the challenge to store and process them must be addressed with data compression. In this review we first answer the question “why compression” in a quantitative manner. Then we also answer the questions “what” and “how”, by sketching the fundamental compression ideas, describing the main sequencing data types and formats, and comparing the specialized compression algorithms and tools. Finally, we go back to the question “why compression” and give other, perhaps surprising answers, demonstrating the pervasiveness of data compression techniques in computational biology. PMID:24252160

  9. Compressed Air/Vacuum Transportation Techniques

    NASA Astrophysics Data System (ADS)

    Guha, Shyamal

    2011-03-01

    General theory of compressed air/vacuum transportation will be presented. In this transportation, a vehicle (such as an automobile or a rail car) is powered either by compressed air or by air at near vacuum pressure. Four version of such transportation is feasible. In all versions, a ``c-shaped'' plastic or ceramic pipe lies buried a few inches under the ground surface. This pipe carries compressed air or air at near vacuum pressure. In type I transportation, a vehicle draws compressed air (or vacuum) from this buried pipe. Using turbine or reciprocating air cylinder, mechanical power is generated from compressed air (or from vacuum). This mechanical power transferred to the wheels of an automobile (or a rail car) drives the vehicle. In type II-IV transportation techniques, a horizontal force is generated inside the plastic (or ceramic) pipe. A set of vertical and horizontal steel bars is used to transmit this force to the automobile on the road (or to a rail car on rail track). The proposed transportation system has following merits: virtually accident free; highly energy efficient; pollution free and it will not contribute to carbon dioxide emission. Some developmental work on this transportation will be needed before it can be used by the traveling public. The entire transportation system could be computer controlled.

  10. Detecting faces in the wavelet compressed domain

    NASA Astrophysics Data System (ADS)

    Li, Xiaohua; Shen, LanSun

    2005-07-01

    A novel technique that can implement face detection directly in the wavelet compressed domain is presented in this paper. The algorithm takes the entropy decoding and inverse quantized wavelet transform coefficients of JPEG2000 picture as input, and outputs the locations of the detected faces. The main contribution of this work is in proposing a multi-level gradient energy representation of face pattern based on wavelet compressed data, which permits pertinent high contrast facial parts, such as eyes, nose and mouth, to be highlighted in a compact mode no matter the face is big or small. A neural-network based classifier is designed to decide a gradient energy pattern as face or non-face. In contrast to the traditional spatial-domain techniques, the proposed compressed domain technique eliminates the unnecessary decompression step and thus has lower computational complexity. Moreover, compared with the previous methods based on DCT compressed domain, the proposed multi-level gradient energy presentation removes the complex spatial scaling operation in compressed domain and overcomes block quantization problem. Based on test results of a variety of pictures, the presented algorithm was found to be more efficient and effective than the previous related methods.

  11. GPA/GPSA/OSU-Okmulgee natural gas compression technician training program

    SciTech Connect

    Doede, S.

    1999-07-01

    Approximately one year ago, OSU-Okmulgee and the Gas Processors Association began discussions about the possibility of developing a natural Gas Technician Training Program for GPA members. Following a presentation to the Membership and Services Committee, Chairman John Ehlers solicited and obtained the approval of the GPA Executive Committee to sponsor the program. Participation in the program was also made available to GPSA members. The purpose of the program is to upgrade the technical competency and professional level of incoming natural gas compression technicians. It educates students to analytically diagnose, service and maintain gas compression equipment and systems using industry recommended procedures, special tools and service information. It also provides course content, which will enable successful graduates to advance in position after additional experience, and to understand new systems, technologies and components as they are introduced. The two-year Associate-In-Applied Science Degree program includes six successive college semesters. Nearly one-half of the time is designated for technical/academic education at Oklahoma State University-Okmulgee with the balance of time allocated for on-the-job internship experiences at sponsoring GPA/GPSA members. Each block of technical education and general education course work is followed by an immediate work experience time period designated to reinforce the technical and general education. These time periods are approximately seven and one-half weeks in length each. It is essential for the success of the students and the program that the students' education at OSU-Okmulgee and work experiences at GPA/GPSA member facilities be closely aligned for maximum student learning and retention. In addition to technical classes on gas compression equipment and components, the courses offered in math, speech, technical writing, psychology and ethics for example, prepare students to be able to communicate well, get along with others and be responsible and productive employees.

  12. Learning random networks for compression of still and moving images

    NASA Technical Reports Server (NTRS)

    Gelenbe, Erol; Sungur, Mert; Cramer, Christopher

    1994-01-01

    Image compression for both still and moving images is an extremely important area of investigation, with numerous applications to videoconferencing, interactive education, home entertainment, and potential applications to earth observations, medical imaging, digital libraries, and many other areas. We describe work on a neural network methodology to compress/decompress still and moving images. We use the 'point-process' type neural network model which is closer to biophysical reality than standard models, and yet is mathematically much more tractable. We currently achieve compression ratios of the order of 120:1 for moving grey-level images, based on a combination of motion detection and compression. The observed signal-to-noise ratio varies from values above 25 to more than 35. The method is computationally fast so that compression and decompression can be carried out in real-time. It uses the adaptive capabilities of a set of neural networks so as to select varying compression ratios in real-time as a function of quality achieved. It also uses a motion detector which will avoid retransmitting portions of the image which have varied little from the previous frame. Further improvements can be achieved by using on-line learning during compression, and by appropriate compensation of nonlinearities in the compression/decompression scheme. We expect to go well beyond the 250:1 compression level for color images with good quality levels.

  13. A Week for Space

    ERIC Educational Resources Information Center

    Comstock, Diane

    2008-01-01

    Space Week focuses on concepts that enable students to make concrete observations in the early grades (K-2) and move to concepts that help students develop their internet research and writing skills in middle and upper grades (Grades 3-5), and culminates with the development of science investigation design skills (Grade 6). To help launch your…

  14. Phun Week: Understanding Physiology

    ERIC Educational Resources Information Center

    Limson, Mel; Matyas, Marsha Lakes

    2009-01-01

    Topics such as sports, exercise, health, and nutrition can make the science of physiology relevant and engaging for students. In addition, many lessons on these topics, such as those on the cardiovascular, respiratory, and digestive systems, align with national and state life science education standards. Physiology Understanding Week (PhUn…

  15. A Week of Observations

    ERIC Educational Resources Information Center

    Colasacco, Jenne

    2011-01-01

    Even the most effective teachers have room to grow, but it's not always easy for principals to give adequate guidance through short observations. High school principal Jenne Colasacco decided to bring more depth to her observations by observing each of her teachers during one class for an entire week. The new observation structure, which included…

  16. Groundmother Earth Week Outreach

    USGS Multimedia Gallery

    Louis Leader Charge demonstrated hydrologic data collection equipment for middle school and high school students at the St. Francis Indian School in St. Francis, SD, on the Rosebud Indian Reservation on April 20, 2015 for UNCI MAKA (Grandmother Earth) week. Louis also provided an overview of USGS ac...

  17. Swahili 12 Weeks Course.

    ERIC Educational Resources Information Center

    Defense Language Inst., Washington, DC.

    This 12-weeks course in basic Swahili comprises 55 lesson units in five volumes. The general course format consists of (1) perception drills for comprehension, oral production, and association using "situational picture" illustrations; (2) dialogs in English and Swahili, with cartoon guides; (3) sequenced pattern and recombination drills, and (4)…

  18. Longwave infrared compressive hyperspectral imager

    NASA Astrophysics Data System (ADS)

    Dupuis, Julia R.; Kirby, Michael; Cosofret, Bogdan R.

    2015-06-01

    Physical Sciences Inc. (PSI) is developing a longwave infrared (LWIR) compressive sensing hyperspectral imager (CS HSI) based on a single pixel architecture for standoff vapor phase plume detection. The sensor employs novel use of a high throughput stationary interferometer and a digital micromirror device (DMD) converted for LWIR operation in place of the traditional cooled LWIR focal plane array. The CS HSI represents a substantial cost reduction over the state of the art in LWIR HSI instruments. Radiometric improvements for using the DMD in the LWIR spectral range have been identified and implemented. In addition, CS measurement and sparsity bases specifically tailored to the CS HSI instrument and chemical plume imaging have been developed and validated using LWIR hyperspectral image streams of chemical plumes. These bases enable comparable statistics to detection based on uncompressed data. In this paper, we present a system model predicting the overall performance of the CS HSI system. Results from a breadboard build and test validating the system model are reported. In addition, the measurement and sparsity basis work demonstrating the plume detection on compressed hyperspectral images is presented.

  19. Compress Your Files

    ERIC Educational Resources Information Center

    Branzburg, Jeffrey

    2005-01-01

    File compression enables data to be squeezed together, greatly reducing file size. Why would someone want to do this? Reducing file size enables the sending and receiving of files over the Internet more quickly, the ability to store more files on the hard drive, and the ability pack many related files into one archive (for example, all files…

  20. The Compressed Video Experience.

    ERIC Educational Resources Information Center

    Weber, John

    In the fall semester 1995, Southern Arkansas University- Magnolia (SAU-M) began a two semester trial delivering college classes via a compressed video link between SAU-M and its sister school Southern Arkansas University Tech (SAU-T) in Camden. As soon as the University began broadcasting and receiving classes, it was discovered that using the…

  1. zlib compression library

    E-print Network

    Gailly, Jean-loup; Adler, Mark

    2004-12-01

    zlib 1.2.1 is a general purpose data compression library written in the C programming language. All the code is thread safe. The data format used by the zlib library is described by RFCs (Request for Comments) 1950 to 1952 in the files http...

  2. Nonlinear Frequency Compression

    PubMed Central

    Scollie, Susan; Glista, Danielle; Seelisch, Andreas

    2013-01-01

    Frequency lowering technologies offer an alternative amplification solution for severe to profound high frequency hearing losses. While frequency lowering technologies may improve audibility of high frequency sounds, the very nature of this processing can affect the perceived sound quality. This article reports the results from two studies that investigated the impact of a nonlinear frequency compression (NFC) algorithm on perceived sound quality. In the first study, the cutoff frequency and compression ratio parameters of the NFC algorithm were varied, and their effect on the speech quality was measured subjectively with 12 normal hearing adults, 12 normal hearing children, 13 hearing impaired adults, and 9 hearing impaired children. In the second study, 12 normal hearing and 8 hearing impaired adult listeners rated the quality of speech in quiet, speech in noise, and music after processing with a different set of NFC parameters. Results showed that the cutoff frequency parameter had more impact on sound quality ratings than the compression ratio, and that the hearing impaired adults were more tolerant to increased frequency compression than normal hearing adults. No statistically significant differences were found in the sound quality ratings of speech-in-noise and music stimuli processed through various NFC settings by hearing impaired listeners. These findings suggest that there may be an acceptable range of NFC settings for hearing impaired individuals where sound quality is not adversely affected. These results may assist an Audiologist in clinical NFC hearing aid fittings for achieving a balance between high frequency audibility and sound quality. PMID:23539261

  3. Compression: Rent or own

    SciTech Connect

    Cahill, C.

    1997-07-01

    Historically, the decision to purchase or rent compression has been set as a corporate philosophy. As companies decentralize, there seems to be a shift away from corporate philosophy toward individual profit centers. This has led the decision to rent versus purchase to be looked at on a regional or project-by-project basis.

  4. Video-compression scheme

    NASA Technical Reports Server (NTRS)

    Lum, H., Jr.; Matsumoto, Y.

    1980-01-01

    Video compression circuit divides picture into elements transmitted at reduced data rate. By sampling elements along diagonals in N-by-N picture blocks, system gives picture quality comparable to that of standard television and superior to most pseudorandom sampling schemes.

  5. Compressed gas handbook

    NASA Technical Reports Server (NTRS)

    Cota, R. A.; Kunkle, J. S.; Wilson, S. D.

    1971-01-01

    Handbook includes thermodynamic and related fluid flow data required to analyze high pressure compressible and incompressible fluid systems. Some theory and applications include thermodynamic fundamentals, gas behavior, adiabatic and isentropic flow, shock waves, flow measurement, and adiabatic and isothermal friction flow in pipes.

  6. Data Compression introduction

    E-print Network

    Sedgewick, Robert

    a central role in communications technology, · Braille. · Morse code. · Telephone system. and is part-length encoding Use different number of bits to encode different characters. Ex. Morse code. Issue: ambiguity1 Data Compression introduction basic coding schemes an application entropy LZW codes References

  7. Compressed Gas Cylinder Policy

    E-print Network

    Contact: Director of Environmental Health and Safety TSweitze@mines.edu Issued: April 26, 2012 Revised: Director of Environmental Health and Safety TSweitze@mines.edu Issued: April 26, 2012 Revised: June 19Compressed Gas Cylinder Policy Responsible Administrative Unit: Finance and Administration Policy

  8. Effect of ambient conditions and fuel properties on homogeneous charge compression ignition engine operation

    E-print Network

    Andreae, Morgan M. (Morgan MacKenzie)

    2006-01-01

    Practical application of Homogeneous Charge Compression Ignition (HCCI) combustion must demonstrate robust responses to variations in environmental conditions. This work examines the impact of ambient conditions and fuel ...

  9. Functional Compression Through Graph Coloring

    E-print Network

    Doshi, Vishal

    Motivated by applications to sensor networks and privacy preserving databases, we consider the problem of functional compression. The objective is to separately compress possibly correlated discrete sources such that an ...

  10. Contemporary Mathematics Wavelet Image Compression

    E-print Network

    Song, Myung-Sin

    detection and fingerprint compression, image de-noising, image enhancement, image recognition, diagnostic Mathematics Subject Classification. Primary 42C40. Key words and phrases. Wavelet Analysis, Image CompressionContemporary Mathematics Wavelet Image Compression Myung-Sin Song This paper is dedicated to my

  11. Progressive transmission and compression images

    NASA Technical Reports Server (NTRS)

    Kiely, A. B.

    1996-01-01

    We describe an image data compression strategy featuring progressive transmission. The method exploits subband coding and arithmetic coding for compression. We analyze the Laplacian probability density, which closely approximates the statistics of individual subbands, to determine a strategy for ordering the compressed subband data in a way that improves rate-distortion performance. Results are presented for a test image.

  12. January 3, 2009 Compressed Sensing

    E-print Network

    Linial, Nathan "Nati"

    January 3, 2009 Compressed Sensing: Basic results and self contained proofs Shai Shalev-Shwartz Abstract Compressed sensing is a linear dimensionality reduction technique which utilizes a prior? Can't we just directly measure the part that won't end up being thrown away? Compressed sensing

  13. 76 FR 20215 - National Volunteer Week, 2011

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-12

    ...Proclamation 8649 of April 7, 2011 National Volunteer Week, 2011 By the President of the...story has been marked by the service of volunteers. Generations of selfless individuals...solve problems when we work together. Volunteers are the lifeblood of our schools...

  14. 75 FR 20891 - National Volunteer Week, 2010

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-21

    ...Proclamation 8500 of April 16, 2010 National Volunteer Week, 2010 By the President of the...return. The American story is a story of volunteers--of patriots who fought for our founding...up struggling communities. All were volunteers, and their work changed our...

  15. IWSA WEEKLY UPDATE January 30, 2009

    E-print Network

    Columbia University

    to promote renewable energy technologies, create green jobs and tackle pollution and climate change. Reps and climate policy. The caucus also worked to promote the inclusion of green technology measures credit for waste-to-energy and other renewables. Consideration by the full Senate is expected next week

  16. Shock compression of geological materials

    NASA Astrophysics Data System (ADS)

    Kirk, S.; Braithwaite, C.; Williamson, D.; Jardine, A.

    2014-05-01

    Understanding the shock compression of geological materials is important for many applications, and is particularly important to the mining industry. During blast mining the response to shock loading determines the wave propagation speed and resulting fragmentation of the rock. The present work has studied the Hugoniot of two geological materials; Lake Quarry Granite and Gosford Sandstone. For samples of these materials, the composition was characterised in detail. The Hugoniot of Lake Quarry Granite was predicted from this information as the material is fully dense and was found to be in good agreement with the measured Hugoniot. Gosford Sandstone is porous and undergoes compaction during shock loading. Such behaviour is similar to other granular material and we show how it can be described using a P-a compaction model.

  17. Digital mammography, cancer screening: Factors important for image compression

    NASA Technical Reports Server (NTRS)

    Clarke, Laurence P.; Blaine, G. James; Doi, Kunio; Yaffe, Martin J.; Shtern, Faina; Brown, G. Stephen; Winfield, Daniel L.; Kallergi, Maria

    1993-01-01

    The use of digital mammography for breast cancer screening poses several novel problems such as development of digital sensors, computer assisted diagnosis (CAD) methods for image noise suppression, enhancement, and pattern recognition, compression algorithms for image storage, transmission, and remote diagnosis. X-ray digital mammography using novel direct digital detection schemes or film digitizers results in large data sets and, therefore, image compression methods will play a significant role in the image processing and analysis by CAD techniques. In view of the extensive compression required, the relative merit of 'virtually lossless' versus lossy methods should be determined. A brief overview is presented here of the developments of digital sensors, CAD, and compression methods currently proposed and tested for mammography. The objective of the NCI/NASA Working Group on Digital Mammography is to stimulate the interest of the image processing and compression scientific community for this medical application and identify possible dual use technologies within the NASA centers.

  18. Data Compression for Helioseismology

    NASA Astrophysics Data System (ADS)

    Löptien, Björn

    2015-10-01

    Efficient data compression will play an important role for several upcoming and planned space missions involving helioseismology, such as Solar Orbiter. Solar Orbiter, to be launched in October 2018, will be the next space mission involving helioseismology. The main characteristic of Solar Orbiter lies in its orbit. The spacecraft will have an inclined solar orbit, reaching a solar latitude of up to 33 deg. This will allow, for the first time, probing the solar poles using local helioseismology. In addition, combined observations of Solar Orbiter and another helioseismic instrument will be used to study the deep interior of the Sun using stereoscopic helioseismology. The Doppler velocity and continuum intensity images of the Sun required for helioseismology will be provided by the Polarimetric and Helioseismic Imager (PHI). Major constraints for helioseismology with Solar Orbiter are the low telemetry and the (probably) short observing time. In addition, helioseismology of the solar poles requires observations close to the solar limb, even from the inclined orbit of Solar Orbiter. This gives rise to systematic errors. In this thesis, I derived a first estimate of the impact of lossy data compression on helioseismology. I put special emphasis on the Solar Orbiter mission, but my results are applicable to other planned missions as well. First, I studied the performance of PHI for helioseismology. Based on simulations of solar surface convection and a model of the PHI instrument, I generated a six-hour time-series of synthetic Doppler velocity images with the same properties as expected for PHI. Here, I focused on the impact of the point spread function, the spacecraft jitter, and of the photon noise level. The derived power spectra of solar oscillations suggest that PHI will be suitable for helioseismology. The low telemetry of Solar Orbiter requires extensive compression of the helioseismic data obtained by PHI. I evaluated the influence of data compression using data provided by the Helioseismic and Magnetic Imager (HMI). HMI is an instrument onboard the Solar Dynamics Observatory (SDO), launched in 2010. It provides full disk images with high cadence of the continuum intensity, the Doppler-velocity and the full magnetic field vector. Using HMI Doppler-velocity maps, I showed that the signal-to-noise ratio of supergranulation in time-distance helioseismology is robust regarding lossy data compression. In addition, I proved that the accuracy and precision of probing differential rotation with local correlation tracking of granulation is not severely affected by extensive lossy data compression. This indicates that the low telemetry of Solar Orbiter may not be a major challenge for helioseismology.

  19. Engineering Relative Compression of Genomes

    E-print Network

    Grabowski, Szymon

    2011-01-01

    Technology progress in DNA sequencing boosts the genomic database growth at faster and faster rate. Compression, accompanied with random access capabilities, is the key to maintain those huge amounts of data. In this paper we present an LZ77-style compression scheme for relative compression of multiple genomes of the same species. While the solution bears similarity to known algorithms, it offers significantly higher compression ratios at compression speed over a order of magnitude greater. One of the new successful ideas is augmenting the reference sequence with phrases from the other sequences, making more LZ-matches available.

  20. The quest for 'diagnostically lossless' medical image compression: a comparative study of objective quality metrics for compressed medical images

    NASA Astrophysics Data System (ADS)

    Kowalik-Urbaniak, Ilona; Brunet, Dominique; Wang, Jiheng; Koff, David; Smolarski-Koff, Nadine; Vrscay, Edward R.; Wallace, Bill; Wang, Zhou

    2014-03-01

    Our study, involving a collaboration with radiologists (DK,NSK) as well as a leading international developer of medical imaging software (AGFA), is primarily concerned with improved methods of assessing the diagnostic quality of compressed medical images and the investigation of compression artifacts resulting from JPEG and JPEG2000. In this work, we compare the performances of the Structural Similarity quality measure (SSIM), MSE/PSNR, compression ratio CR and JPEG quality factor Q, based on experimental data collected in two experiments involving radiologists. An ROC and Kolmogorov-Smirnov analysis indicates that compression ratio is not always a good indicator of visual quality. Moreover, SSIM demonstrates the best performance, i.e., it provides the closest match to the radiologists' assessments. We also show that a weighted Youden index1 and curve tting method can provide SSIM and MSE thresholds for acceptable compression ratios.

  1. Compressive blind image deconvolution.

    PubMed

    Amizic, Bruno; Spinoulas, Leonidas; Molina, Rafael; Katsaggelos, Aggelos K

    2013-10-01

    We propose a novel blind image deconvolution (BID) regularization framework for compressive sensing (CS) based imaging systems capturing blurred images. The proposed framework relies on a constrained optimization technique, which is solved by a sequence of unconstrained sub-problems, and allows the incorporation of existing CS reconstruction algorithms in compressive BID problems. As an example, a non-convex lp quasi-norm with is employed as a regularization term for the image, while a simultaneous auto-regressive regularization term is selected for the blur. Nevertheless, the proposed approach is very general and it can be easily adapted to other state-of-the-art BID schemes that utilize different, application specific, image/blur regularization terms. Experimental results, obtained with simulations using blurred synthetic images and real passive millimeter-wave images, show the feasibility of the proposed method and its advantages over existing approaches. PMID:23744684

  2. Digital cinema video compression

    NASA Astrophysics Data System (ADS)

    Husak, Walter

    2003-05-01

    The Motion Picture Industry began a transition from film based distribution and projection to digital distribution and projection several years ago. Digital delivery and presentation offers the prospect to increase the quality of the theatrical experience for the audience, reduce distribution costs to the distributors, and create new business opportunities for the theater owners and the studios. Digital Cinema also presents an opportunity to provide increased flexibility and security of the movies for the content owners and the theater operators. Distribution of content via electronic means to theaters is unlike any of the traditional applications for video compression. The transition from film-based media to electronic media represents a paradigm shift in video compression techniques and applications that will be discussed in this paper.

  3. Cerebral compression by myeloma.

    PubMed Central

    Stark, R J; Henson, R A

    1981-01-01

    A patient presented with right hemiparesis, dysphasia and a large, palpable, left frontoparietal mass arising from the calvarial diploe. A diagnosis of multiple myeloma was made on radiological and biochemical grounds, together with bone marrow examination. Few cases of cerebral compression by a massive plasmacytoma have been reported, but in some surgical management produced clinical deterioration. The present case was treated with radiotherapy and chemotherapy, with satisfactory results. Images PMID:7310424

  4. Compressive ghost imaging

    E-print Network

    Ori Katz; Yaron Bromberg; Yaron Silberberg

    2009-08-09

    We describe an advanced image reconstruction algorithm for pseudothermal ghost imaging, reducing the number of measurements required for image recovery by an order of magnitude. The algorithm is based on compressed sensing, a technique that enables the reconstruction of an N-pixel image from much less than N measurements. We demonstrate the algorithm using experimental data from a pseudothermal ghost-imaging setup. The algorithm can be applied to data taken from past pseudothermal ghost-imaging experiments, improving the reconstruction's quality.

  5. At Least 39 Weeks

    MedlinePLUS Videos and Cool Tools

    ... Fighting premature birth About us Annual report Our work Community impact Global programs Research Need help? Local ... Fighting premature birth About us Annual report Our work Community impact Global programs Research Need help? Local ...

  6. Compressive and classical hyperspectral systems: a fundamental comparison

    NASA Astrophysics Data System (ADS)

    Shay, Adi; August, Isaac Y.; Stern, Adrian

    2015-05-01

    Hyperspectral imagery involves capturing and processing a tremendous amount of data, which sets severe system resource requirements. This has motivated the application of compressive sensing for different spectroscopic and spectroscopic imager systems. Several new compressive hyperspectral architectures have been designed to stretch the common limitations of classical systems. However, the application of the compressive sensing framework involves design of system architectures that differ significantly from the conventional ones. Since compressive sensing differs essentially from conventional sensing, it cannot be implemented for hyperspectral imaging by simply modifying one of the components of a conventional hyperspectral system, rather it requires a complete new design. In this work we present a comparison between four compressive hyperspectral architectures to conventional architectures. The compressive hyperspectral sensing compared are: Coded Aperture Snapshot Spectral Imaging (CASSI), Compressive HS Imaging by Separable Spatial And Spectral Operators (CHISSS), (Liquid-crystal Compressive spectral Imager) LiCSI and (Spectral Single-Pixel) SSP systems. Those methods are compared to conventional spatial/spectral scanning hyperspectral such as pushbroom, whiskbroom and color filter techniques. A fundamental comparison between these architectures is presented in terms of optical system volume and radiometric efficiency.

  7. Managing venous leg ulcers using compression therapy and dressings.

    PubMed

    Powell, Gail; Wicks, Gill; Will, Katrin

    Patient comfort and satisfaction with both compression therapy and wound care are critical to the success of venous leg ulcer treatment. This study observed 22 patients with venous leg ulcers treated over 12 weeks with two-layer compression hosiery and a range of wound dressings. The mean duration of the ulcers was 10.5 months and 48% had a history of recurrent ulcers. Half the ulcers healed within 12 weeks; there was an increase in the proportion of patients reporting 'no impairment' to their mobility, but it was not significant. The ease of donning the two-layer hosiery was rated as excellent or good at 86% of control visits and the ease of doffing at 78%. In 95% of cases the clinicians said they would use the same combination of products again and 73% of patients were satisfied with it. PMID:26266566

  8. The thermodynamics of compressed air exergy storage

    SciTech Connect

    Osterle, J.F. )

    1991-03-01

    This paper analyzes the Compressed Air Energy Storage (CAES) concept as an exergy storage concept. A thermodynamic analysis involving the application of the first and second laws of thermodynamics to both the charge and discharge processes is made. Works, heats, cavern energy changes, cavern exergy changes, and dissipations are evaluated for two designs - one idealized and the other more practical. An appropriate effectiveness based on the exergy concept is defined and evaluated.

  9. New Regenerative Cycle for Vapor Compression Refrigeration

    SciTech Connect

    Mark J. Bergander

    2005-08-29

    The main objective of this project is to confirm on a well-instrumented prototype the theoretically derived claims of higher efficiency and coefficient of performance for geothermal heat pumps based on a new regenerative thermodynamic cycle as comparing to existing technology. In order to demonstrate the improved performance of the prototype, it will be compared to published parameters of commercially available geothermal heat pumps manufactured by US and foreign companies. Other objectives are to optimize the design parameters and to determine the economic viability of the new technology. Background (as stated in the proposal): The proposed technology closely relates to EERE mission by improving energy efficiency, bringing clean, reliable and affordable heating and cooling to the residential and commercial buildings and reducing greenhouse gases emission. It can provide the same amount of heating and cooling with considerably less use of electrical energy and consequently has a potential of reducing our nations dependence on foreign oil. The theoretical basis for the proposed thermodynamic cycle was previously developed and was originally called a dynamic equilibrium method. This theory considers the dynamic equations of state of the working fluid and proposes the methods for modification of T-S trajectories of adiabatic transformation by changing dynamic properties of gas, such as flow rate, speed and acceleration. The substance of this proposal is a thermodynamic cycle characterized by the regenerative use of the potential energy of two-phase flow expansion, which in traditional systems is lost in expansion valves. The essential new features of the process are: (1) The application of two-step throttling of the working fluid and two-step compression of its vapor phase. (2) Use of a compressor as the initial step compression and a jet device as a second step, where throttling and compression are combined. (3) Controlled ratio of a working fluid at the first and second step of compression. In the proposed system, the compressor compresses the vapor only to 50-60% of the final pressure, while the additional compression is provided by a jet device using internal potential energy of the working fluid flow. Therefore, the amount of mechanical energy required by a compressor is significantly reduced, resulting in the increase of efficiency (either COP or EER). The novelty of the cycle is in the equipment and in the way the multi-staging is accomplished. The anticipated result will be a new refrigeration system that requires less energy to accomplish a cooling task. The application of this technology will be for more efficient designs of: (1) Industrial chillers, (2) Refrigeration plants, (3) Heat pumps, (4) Gas Liquefaction plants, (5) Cryogenic systems.

  10. Elective Delivery Before 39 Weeks

    MedlinePLUS

    ... Delivery, and Postpartum Care Elective Delivery Before 39 Weeks • What is a “medically indicated” delivery? • What is ... the baby grow and develop during the last weeks of pregnancy? • What are the risks for babies ...

  11. Application of compressed sensing to the simulation of atomic systems

    PubMed Central

    Andrade, Xavier; Sanders, Jacob N.; Aspuru-Guzik, Alán

    2012-01-01

    Compressed sensing is a method that allows a significant reduction in the number of samples required for accurate measurements in many applications in experimental sciences and engineering. In this work, we show that compressed sensing can also be used to speed up numerical simulations. We apply compressed sensing to extract information from the real-time simulation of atomic and molecular systems, including electronic and nuclear dynamics. We find that, compared to the standard discrete Fourier transform approach, for the calculation of vibrational and optical spectra the total propagation time, and hence the computational cost, can be reduced by approximately a factor of five. PMID:22891294

  12. Seismic full waveform inversion from compressive measurements

    NASA Astrophysics Data System (ADS)

    Ramirez, Ana; Arce, Gonzalo R.

    2015-05-01

    Traditional methods in seismic acquisition require sources and geophones that are uniformly located along a spatial line, using the Nyquist sampling rate. Depending on the area to be explored, it can be necessary to use seismic surveys with large offsets, or decrease the separation between adjacent geophones to improve the resolution, which generates very high volumes of data. It makes the exploration process more difficult and particularly expensive. This work presents the reconstruction of a compressive set of seismic traces acquired using the compressive sensing paradigm where the pair of sources and geophones are randomly located along the spatial line. The recovery of the wavefield from compressive measurements is feasible due to the capabilities of Curvelets on representing wave propagators with only a small set of coefficients. The method first uses the compressive samples to find a sparse vector representation of each pixel in a 2-D Curvelet dictionary. The sparse vector representation is estimated by solving a sparsity constrained optimization problem using the Gradient Projection for Sparse Reconstruction (GPSR) method. The estimated vector is then used to compute the seismic velocity profiles via acoustic Full Waveform Inversion (FWI). Simulations of the reconstructed image gathers and the resulting seismic velocity profiles illustrate the performance of the method. An improvement in the resulting images is obtained in comparison with traditional F-K filtering used in seismic data processing when traces are missing.

  13. Comparative data compression techniques and multi-compression results

    NASA Astrophysics Data System (ADS)

    Hasan, M. R.; Ibrahimy, M. I.; Motakabber, S. M. A.; Ferdaus, M. M.; Khan, M. N. H.

    2013-12-01

    Data compression is very necessary in business data processing, because of the cost savings that it offers and the large volume of data manipulated in many business applications. It is a method or system for transmitting a digital image (i.e., an array of pixels) from a digital data source to a digital data receiver. More the size of the data be smaller, it provides better transmission speed and saves time. In this communication, we always want to transmit data efficiently and noise freely. This paper will provide some compression techniques for lossless text type data compression and comparative result of multiple and single compression, that will help to find out better compression output and to develop compression algorithms.

  14. Image compression in local helioseismology

    NASA Astrophysics Data System (ADS)

    Löptien, B.; Birch, A. C.; Gizon, L.; Schou, J.

    2014-11-01

    Context. Several upcoming helioseismology space missions are very limited in telemetry and will have to perform extensive data compression. This requires the development of new methods of data compression. Aims: We give an overview of the influence of lossy data compression on local helioseismology. We investigate the effects of several lossy compression methods (quantization, JPEG compression, and smoothing and subsampling) on power spectra and time-distance measurements of supergranulation flows at disk center. Methods: We applied different compression methods to tracked and remapped Dopplergrams obtained by the Helioseismic and Magnetic Imager onboard the Solar Dynamics Observatory. We determined the signal-to-noise ratio of the travel times computed from the compressed data as a function of the compression efficiency. Results: The basic helioseismic measurements that we consider are very robust to lossy data compression. Even if only the sign of the velocity is used, time-distance helioseismology is still possible. We achieve the best results by applying JPEG compression on spatially subsampled data. However, our conclusions are only valid for supergranulation flows at disk center and may not be valid for all helioseismology applications.

  15. Impacts of shift work on sleep and circadian rhythms.

    PubMed

    Boivin, D B; Boudreau, P

    2014-10-01

    Shift work comprises work schedules that extend beyond the typical "nine-to-five" workday, wherein schedules often comprise early work start, compressed work weeks with 12-hour shifts, and night work. According to recent American and European surveys, between 15 and 30% of adult workers are engaged in some type of shift work, with 19% of the European population reportedly working at least 2 hours between 22:00 and 05:00. The 2005 International Classification of Sleep Disorders estimates that a shift work sleep disorder can be found in 2-5% of workers. This disorder is characterized by excessive sleepiness and/or sleep disruption for at least one month in relation with the atypical work schedule. Individual tolerance to shift work remains a complex problem that is affected by the number of consecutive work hours and shifts, the rest periods, and the predictability of work schedules. Sleepiness usually occurs during night shifts and is maximal at the end of the night. Impaired vigilance and performance occur around times of increased sleepiness and can seriously compromise workers' health and safety. Indeed, workers suffering from a shift work sleep-wake disorder can fall asleep involuntarily at work or while driving back home after a night shift. Working on atypical shifts has important socioeconomic impacts as it leads to an increased risk of accidents, workers' impairment and danger to public safety, especially at night. The aim of the present review is to review the circadian and sleep-wake disturbances associated with shift work as well as their medical impacts. PMID:25246026

  16. Ultrasound beamforming using compressed data.

    PubMed

    Li, Yen-Feng; Li, Pai-Chi

    2012-05-01

    The rapid advancements in electronics technologies have made software-based beamformers for ultrasound array imaging feasible, thus facilitating the rapid development of high-performance and potentially low-cost systems. However, one challenge to realizing a fully software-based system is transferring data from the analog front end to the software back end at rates of up to a few gigabits per second. This study investigated the use of data compression to reduce the data transfer requirements and optimize the associated trade-off with beamforming quality. JPEG and JPEG2000 compression techniques were adopted. The acoustic data of a line phantom were acquired with a 128-channel array transducer at a center frequency of 3.5 MHz, and the acoustic data of a cyst phantom were acquired with a 64-channel array transducer at a center frequency of 3.33 MHz. The receive-channel data associated with each transmit event are separated into 8 × 8 blocks and several tiles before JPEG and JPEG2000 data compression is applied, respectively. In one scheme, the compression was applied to raw RF data, while in another only the amplitude of baseband data was compressed. The maximum compression ratio of RF data compression to produce an average error of lower than 5 dB was 15 with JPEG compression and 20 with JPEG2000 compression. The image quality is higher with baseband amplitude data compression than with RF data compression; although the maximum overall compression ratio (compared with the original RF data size), which was limited by the data size of uncompressed phase data, was lower than 12, the average error in this case was lower than 1 dB when the compression ratio was lower than 8. PMID:22434817

  17. The effect of nearly steady shock waves in ramp compression experiments

    NASA Astrophysics Data System (ADS)

    Fratanduono, D. E.; Smith, R. F.; Braun, D. G.; Patterson, J. R.; Kraus, R. G.; Perry, T. S.; Arsenlis, A.; Collins, G. W.; Eggert, J. H.

    2015-06-01

    The iterative Lagrangian analysis (ILA) applied to free-surface velocity measurements of ramp-compressed samples is an established technique to determine the stress-density response of materials up to 50 Mbar pressures. In this work, we examine the accuracy of the ILA of ramp compression profiles with multiple shock waves present through the analysis of simulated compression profiles. The results presented indicate that ramp-compression data with weak shock waves can be analyzed using the ILA to quantitatively measure the absolute stress and density along the compression path.

  18. Blind compressive sensing dynamic MRI.

    PubMed

    Lingala, Sajan Goud; Jacob, Mathews

    2013-06-01

    We propose a novel blind compressive sensing (BCS) frame work to recover dynamic magnetic resonance images from undersampled measurements. This scheme models the dynamic signal as a sparse linear combination of temporal basis functions, chosen from a large dictionary. In contrast to classical compressed sensing, the BCS scheme simultaneously estimates the dictionary and the sparse coefficients from the undersampled measurements. Apart from the sparsity of the coefficients, the key difference of the BCS scheme with current low rank methods is the nonorthogonal nature of the dictionary basis functions. Since the number of degrees-of-freedom of the BCS model is smaller than that of the low-rank methods, it provides improved reconstructions at high acceleration rates. We formulate the reconstruction as a constrained optimization problem; the objective function is the linear combination of a data consistency term and sparsity promoting l1 prior of the coefficients. The Frobenius norm dictionary constraint is used to avoid scale ambiguity. We introduce a simple and efficient majorize-minimize algorithm, which decouples the original criterion into three simpler subproblems. An alternating minimization strategy is used, where we cycle through the minimization of three simpler problems. This algorithm is seen to be considerably faster than approaches that alternates between sparse coding and dictionary estimation, as well as the extension of K-SVD dictionary learning scheme. The use of the l1 penalty and Frobenius norm dictionary constraint enables the attenuation of insignificant basis functions compared to the l0 norm and column norm constraint assumed in most dictionary learning algorithms; this is especially important since the number of basis functions that can be reliably estimated is restricted by the available measurements. We also observe that the proposed scheme is more robust to local minima compared to K-SVD method, which relies on greedy sparse coding. Our phase transition experiments demonstrate that the BCS scheme provides much better recovery rates than classical Fourier-based CS schemes, while being only marginally worse than the dictionary aware setting. Since the overhead in additionally estimating the dictionary is low, this method can be very useful in dynamic magnetic resonance imaging applications, where the signal is not sparse in known dictionaries. We demonstrate the utility of the BCS scheme in accelerating contrast enhanced dynamic data. We observe superior reconstruction performance with the BCS scheme in comparison to existing low rank and compressed sensing schemes. PMID:23542951

  19. Upcoming musical events..... Second Week

    E-print Network

    Oxford, University of

    Upcoming musical events..... Second Week: Friday 4th May at 1.30pm Solo recital Alice Evans - Flute acclaimed all male a cappella group Sixth Week: Friday 1st June at 1.30pm Francis Gush ­ Flute and Voice Seventh Week: Friday 8th June at 1.30pm Solo recital Claire Wickes - Flute. Finals recital preview! Friday

  20. 76 FR 58711 - National Farm Safety and Health Week, 2011

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-21

    ... the two hundred and thirty-sixth. (Presidential Sig.) [FR Doc. 2011-24445 Filed 9-20-11; 11:15 am... Documents#0;#0; ] Proclamation 8716 of September 16, 2011 National Farm Safety and Health Week, 2011 By the... dream-- passing on proud traditions of hard work and commitment to their children. This week,...

  1. On the characterisation of the dynamic compressive behaviour of silicon carbides subjected to isentropic compression experiments

    NASA Astrophysics Data System (ADS)

    Zinszner, Jean-Luc; Erzar, Benjamin; Forquin, Pascal; Barthélémy, François

    2015-09-01

    Ceramic materials are commonly used as protective materials particularly due to their very high hardness and compressive strength. However, the microstructure of a ceramic has a great influence on its compressive strength and on its ballistic efficiency. To study the influence of microstructural parameters on the dynamic compressive behaviour of silicon carbides, isentropic compression experiments have been performed on two silicon carbide grades using a high pulsed power generator called GEPI. Contrary to plate impact experiments, the use of the GEPI device and of the lagrangian analysis allows determining the whole loading path. The two SiC grades studied present different Hugoniot elastic limit (HEL) due to their different microstructures. For these materials, the experimental technique allowed evaluating the evolution of the equivalent stress during the dynamic compression. It has been observed that these two grades present a work hardening more or less pronounced after the HEL. The densification of the material seems to have more influence on the HEL than the grain size.

  2. Chiropractic management of a patient with ulnar nerve compression symptoms: a case report

    PubMed Central

    Illes, Jennifer D.; Johnson, Theodore L.

    2013-01-01

    Objective The purpose of this case report is to describe chiropractic management of a patient with arm and hand numbness and who was suspected to have ulnar nerve compression. Clinical Features A 41-year-old woman presented with hand weakness and numbness along the medial aspect of her right forearm and the 3 most medial fingers. The onset of symptoms presented suddenly, 3 weeks prior, when she woke up in the morning and assumed she had “slept wrong.” The patient’s posture showed protracted shoulders and moderate forward head carriage. Orthopedic assessment revealed symptomatic right elevated arm stress test, grip strength asymmetry, and a Tinel sign at the right cubital tunnel. Intervention and Outcome The patient was treated using chiropractic care, which consisted of manipulative therapy, myofascial therapy, and elastic therapeutic taping. Active home care included performing postural exercises and education about workstation ergonomics. She demonstrated immediate subjective improvement of her numbness and weakness after the first treatment. Over a series of 11 treatments, her symptoms resolved completely; and she was able to perform work tasks without dysfunction. Conclusion Chiropractic treatment consisting of manipulation, soft tissue mobilizations, exercise, and education of workstation ergonomics appeared to reduce the symptoms of ulnar nerve compression symptoms for this patient. PMID:24294148

  3. Compressive sensing in medical imaging.

    PubMed

    Graff, Christian G; Sidky, Emil Y

    2015-03-10

    The promise of compressive sensing, exploitation of compressibility to achieve high quality image reconstructions with less data, has attracted a great deal of attention in the medical imaging community. At the Compressed Sensing Incubator meeting held in April 2014 at OSA Headquarters in Washington, DC, presentations were given summarizing some of the research efforts ongoing in compressive sensing for x-ray computed tomography and magnetic resonance imaging systems. This article provides an expanded version of these presentations. Sparsity-exploiting reconstruction algorithms that have gained popularity in the medical imaging community are studied, and examples of clinical applications that could benefit from compressive sensing ideas are provided. The current and potential future impact of compressive sensing on the medical imaging field is discussed. PMID:25968400

  4. Recent progress in compressible turbulence

    NASA Astrophysics Data System (ADS)

    Chen, Shiyi; Xia, Zhenhua; Wang, Jianchun; Yang, Yantao

    2015-06-01

    In this paper, we review some recent studies on compressible turbulence conducted by the authors' group, which include fundamental studies on compressible isotropic turbulence (CIT) and applied studies on developing a constrained large eddy simulation (CLES) for wall-bounded turbulence. In the first part, we begin with a newly proposed hybrid compact-weighted essentially nonoscillatory (WENO) scheme for a CIT simulation that has been used to construct a systematic database of CIT. Using this database various fundamental properties of compressible turbulence have been examined, including the statistics and scaling of compressible modes, the shocklet-turbulence interaction, the effect of local compressibility on small scales, the kinetic energy cascade, and some preliminary results from a Lagrangian point of view. In the second part, the idea and formulas of the CLES are reviewed, followed by the validations of CLES and some applications in compressible engineering problems.

  5. Energy transfer in compressible turbulence

    NASA Technical Reports Server (NTRS)

    Bataille, Francoise; Zhou, YE; Bertoglio, Jean-Pierre

    1995-01-01

    This letter investigates the compressible energy transfer process. We extend a methodology developed originally for incompressible turbulence and use databases from numerical simulations of a weak compressible turbulence based on Eddy-Damped-Quasi-Normal-Markovian (EDQNM) closure. In order to analyze the compressible mode directly, the well known Helmholtz decomposition is used. While the compressible component has very little influence on the solenoidal part, we found that almost all of the compressible turbulence energy is received from its solenoidal counterpart. We focus on the most fundamental building block of the energy transfer process, the triadic interactions. This analysis leads us to conclude that, at low turbulent Mach number, the compressible energy transfer process is dominated by a local radiative transfer (absorption) in both inertial and energy containing ranges.

  6. Avalanches in Wood Compression.

    PubMed

    Mäkinen, T; Miksic, A; Ovaska, M; Alava, Mikko J

    2015-07-31

    Wood is a multiscale material exhibiting a complex viscoplastic response. We study avalanches in small wood samples in compression. "Woodquakes" measured by acoustic emission are surprisingly similar to earthquakes and crackling noise in rocks and laboratory tests on brittle materials. Both the distributions of event energies and of waiting (silent) times follow power laws. The stress-strain response exhibits clear signatures of localization of deformation to "weak spots" or softwood layers, as identified using digital image correlation. Even though material structure-dependent localization takes place, the avalanche behavior remains scale-free. PMID:26274428

  7. Compressed Air Supply Efficiency 

    E-print Network

    Joseph, B.

    2004-01-01

    . The Data File contains about 12,000 individual lines of data. The Summary Section and a brief portion of the Data File for one of the sites are below. COMPRESSED AIR SYSTEM EFFICIENCY CASE INDEX - XXX Irvine SUMMARY OF RESULTS... XXX Irvine could install a 100 HP compressor with VSD. This would be sufficient to supply the plant 24 hours a day, and will improve the CASE Index even higher. Figure 5. Summary of Report Total CASE KW Index Date/Time North QSI 490 k...

  8. Image Compression Devices

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The Rice algorithm is a "lossless" compression algorithm; it takes an image or other data that has been broken down into short strings of digital data, then processes each string mathematically to reduce the amount of memory required to store or transmit them. It is particularly useful in medical, scientific or engineering applications where all data must be preserved. Originally developed at Jet Propulsion Laboratory, the technology is marketed by Advanced Hardware Architectures, a company started by a former employee of the NASA Microelectronics Research Center.

  9. Avalanches in wood compression

    E-print Network

    Tero Mäkinen; Amandine Miksic; Markus Ovaska; Mikko J. Alava

    2015-06-15

    Wood is a multi-scale material exhibiting a complex viscoplastic response. We study avalanches in small wood samples in compression. "Woodquakes" measured by acoustic emission are surprisingly similar to earthquakes and crackling noise in rocks and laboratory tests on brittle materials. Both the distributions of event energies and of waiting (silent) times follow power-laws. The stress- strain response exhibits clear signatures of localization of deformation to "weak spots" or softwood layers, as identified using Digital Image Correlation. Even though material structure-dependent localization takes place, the avalanche behavior remains scale-free.

  10. Sampling video compression system

    NASA Technical Reports Server (NTRS)

    Matsumoto, Y.; Lum, H. (inventors)

    1977-01-01

    A system for transmitting video signal of compressed bandwidth is described. The transmitting station is provided with circuitry for dividing a picture to be transmitted into a plurality of blocks containing a checkerboard pattern of picture elements. Video signals along corresponding diagonal rows of picture elements in the respective blocks are regularly sampled. A transmitter responsive to the output of the sampling circuitry is included for transmitting the sampled video signals of one frame at a reduced bandwidth over a communication channel. The receiving station is provided with a frame memory for temporarily storing transmitted video signals of one frame at the original high bandwidth frequency.

  11. Avalanches in Wood Compression

    NASA Astrophysics Data System (ADS)

    Mäkinen, T.; Miksic, A.; Ovaska, M.; Alava, Mikko J.

    2015-07-01

    Wood is a multiscale material exhibiting a complex viscoplastic response. We study avalanches in small wood samples in compression. "Woodquakes" measured by acoustic emission are surprisingly similar to earthquakes and crackling noise in rocks and laboratory tests on brittle materials. Both the distributions of event energies and of waiting (silent) times follow power laws. The stress-strain response exhibits clear signatures of localization of deformation to "weak spots" or softwood layers, as identified using digital image correlation. Even though material structure-dependent localization takes place, the avalanche behavior remains scale-free.

  12. How Much Can a Campus Save on Utility Bills by Turning a 5-Workday Week Into a 4­Workday Week 

    E-print Network

    Zhou, J.; Giebler, T.; Wei, G.; Turner, W. D.

    2003-01-01

    -workday week into a 4- workday week (e.g., Monday to Thursday) with 10 working hours each day during the universities summer session. The potential savings come from the fact that the universities can be partially shut down during the prolonged weekends...

  13. How Much Can a Campus Save on Utility Bills by Turning a 5-Workday Week into a 4-Workday Week

    E-print Network

    Zhou, J.; Wei, G.; Giebler, T.; Turner, W. D.

    2003-01-01

    -workday week into a 4-workday week (e.g., Monday to Thursday) with 10 working hours each day during the universities summer session. The potential savings come from the fact that the universities can be partially shut down during the prolonged weekends...

  14. Compression of intensity interferometry signals

    NASA Astrophysics Data System (ADS)

    Ribak, Erez N.; Shulamy, Yaron

    2015-09-01

    Correlations between photon currents from separate light-collectors provide information on the shape of the source. When the light-collectors are well separated, for example in space, transmission of these currents to a central correlator is limited by band-width. We study the possibility of compression of the photon fluxes and find that traditional compression methods have a similar chance of achieving this goal compared to compressed sensing.

  15. Shock compression of precompressed deuterium

    SciTech Connect

    Armstrong, M R; Crowhurst, J C; Zaug, J M; Bastea, S; Goncharov, A F; Militzer, B

    2011-07-31

    Here we report quasi-isentropic dynamic compression and thermodynamic characterization of solid, precompressed deuterium over an ultrafast time scale (< 100 ps) and a microscopic length scale (< 1 {micro}m). We further report a fast transition in shock wave compressed solid deuterium that is consistent with the ramp to shock transition, with a time scale of less than 10 ps. These results suggest that high-density dynamic compression of hydrogen may be possible on microscopic length scales.

  16. Biomedical sensor design using analog compressed sensing

    NASA Astrophysics Data System (ADS)

    Balouchestani, Mohammadreza; Krishnan, Sridhar

    2015-05-01

    The main drawback of current healthcare systems is the location-specific nature of the system due to the use of fixed/wired biomedical sensors. Since biomedical sensors are usually driven by a battery, power consumption is the most important factor determining the life of a biomedical sensor. They are also restricted by size, cost, and transmission capacity. Therefore, it is important to reduce the load of sampling by merging the sampling and compression steps to reduce the storage usage, transmission times, and power consumption in order to expand the current healthcare systems to Wireless Healthcare Systems (WHSs). In this work, we present an implementation of a low-power biomedical sensor using analog Compressed Sensing (CS) framework for sparse biomedical signals that addresses both the energy and telemetry bandwidth constraints of wearable and wireless Body-Area Networks (BANs). This architecture enables continuous data acquisition and compression of biomedical signals that are suitable for a variety of diagnostic and treatment purposes. At the transmitter side, an analog-CS framework is applied at the sensing step before Analog to Digital Converter (ADC) in order to generate the compressed version of the input analog bio-signal. At the receiver side, a reconstruction algorithm based on Restricted Isometry Property (RIP) condition is applied in order to reconstruct the original bio-signals form the compressed bio-signals with high probability and enough accuracy. We examine the proposed algorithm with healthy and neuropathy surface Electromyography (sEMG) signals. The proposed algorithm achieves a good level for Average Recognition Rate (ARR) at 93% and reconstruction accuracy at 98.9%. In addition, The proposed architecture reduces total computation time from 32 to 11.5 seconds at sampling-rate=29 % of Nyquist rate, Percentage Residual Difference (PRD)=26 %, Root Mean Squared Error (RMSE)=3 %.

  17. Magnetic compression laser driving circuit

    DOEpatents

    Ball, Don G. (Livermore, CA); Birx, Dan (Brentwood, CA); Cook, Edward G. (Livermore, CA)

    1993-01-01

    A magnetic compression laser driving circuit is disclosed. The magnetic compression laser driving circuit compresses voltage pulses in the range of 1.5 microseconds at 20 Kilovolts of amplitude to pulses in the range of 40 nanoseconds and 60 Kilovolts of amplitude. The magnetic compression laser driving circuit includes a multi-stage magnetic switch where the last stage includes a switch having at least two turns which has larger saturated inductance with less core material so that the efficiency of the circuit and hence the laser is increased.

  18. Magnetic compression laser driving circuit

    DOEpatents

    Ball, D.G.; Birx, D.; Cook, E.G.

    1993-01-05

    A magnetic compression laser driving circuit is disclosed. The magnetic compression laser driving circuit compresses voltage pulses in the range of 1.5 microseconds at 20 kilovolts of amplitude to pulses in the range of 40 nanoseconds and 60 kilovolts of amplitude. The magnetic compression laser driving circuit includes a multi-stage magnetic switch where the last stage includes a switch having at least two turns which has larger saturated inductance with less core material so that the efficiency of the circuit and hence the laser is increased.

  19. Compressive sensing of sparse tensors.

    PubMed

    Friedland, Shmuel; Li, Qun; Schonfeld, Dan

    2014-10-01

    Compressive sensing (CS) has triggered an enormous research activity since its first appearance. CS exploits the signal's sparsity or compressibility in a particular domain and integrates data compression and acquisition, thus allowing exact reconstruction through relatively few nonadaptive linear measurements. While conventional CS theory relies on data representation in the form of vectors, many data types in various applications, such as color imaging, video sequences, and multisensor networks, are intrinsically represented by higher order tensors. Application of CS to higher order data representation is typically performed by conversion of the data to very long vectors that must be measured using very large sampling matrices, thus imposing a huge computational and memory burden. In this paper, we propose generalized tensor compressive sensing (GTCS)-a unified framework for CS of higher order tensors, which preserves the intrinsic structure of tensor data with reduced computational complexity at reconstruction. GTCS offers an efficient means for representation of multidimensional data by providing simultaneous acquisition and compression from all tensor modes. In addition, we propound two reconstruction procedures, a serial method and a parallelizable method. We then compare the performance of the proposed method with Kronecker compressive sensing (KCS) and multiway compressive sensing (MWCS). We demonstrate experimentally that GTCS outperforms KCS and MWCS in terms of both reconstruction accuracy (within a range of compression ratios) and processing speed. The major disadvantage of our methods (and of MWCS as well) is that the compression ratios may be worse than that offered by KCS. PMID:25137727

  20. Low-Complexity Lossless and Near-Lossless Data Compression Technique for Multispectral Imagery

    NASA Technical Reports Server (NTRS)

    Xie, Hua; Klimesh, Matthew A.

    2009-01-01

    This work extends the lossless data compression technique described in Fast Lossless Compression of Multispectral- Image Data, (NPO-42517) NASA Tech Briefs, Vol. 30, No. 8 (August 2006), page 26. The original technique was extended to include a near-lossless compression option, allowing substantially smaller compressed file sizes when a small amount of distortion can be tolerated. Near-lossless compression is obtained by including a quantization step prior to encoding of prediction residuals. The original technique uses lossless predictive compression and is designed for use on multispectral imagery. A lossless predictive data compression algorithm compresses a digitized signal one sample at a time as follows: First, a sample value is predicted from previously encoded samples. The difference between the actual sample value and the prediction is called the prediction residual. The prediction residual is encoded into the compressed file. The decompressor can form the same predicted sample and can decode the prediction residual from the compressed file, and so can reconstruct the original sample. A lossless predictive compression algorithm can generally be converted to a near-lossless compression algorithm by quantizing the prediction residuals prior to encoding them. In this case, since the reconstructed sample values will not be identical to the original sample values, the encoder must determine the values that will be reconstructed and use these values for predicting later sample values. The technique described here uses this method, starting with the original technique, to allow near-lossless compression. The extension to allow near-lossless compression adds the ability to achieve much more compression when small amounts of distortion are tolerable, while retaining the low complexity and good overall compression effectiveness of the original algorithm.

  1. 76 FR 58711 - National Farm Safety and Health Week, 2011

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-21

    ...generated by our agricultural sector are vital to America's 21st-century economy. Farmers represent the best of the American dream-- passing on proud traditions of hard work and commitment to their children. This week, we celebrate farmers'...

  2. Perceptually Lossless Wavelet Compression

    NASA Technical Reports Server (NTRS)

    Watson, Andrew B.; Yang, Gloria Y.; Solomon, Joshua A.; Villasenor, John

    1996-01-01

    The Discrete Wavelet Transform (DWT) decomposes an image into bands that vary in spatial frequency and orientation. It is widely used for image compression. Measures of the visibility of DWT quantization errors are required to achieve optimal compression. Uniform quantization of a single band of coefficients results in an artifact that is the sum of a lattice of random amplitude basis functions of the corresponding DWT synthesis filter, which we call DWT uniform quantization noise. We measured visual detection thresholds for samples of DWT uniform quantization noise in Y, Cb, and Cr color channels. The spatial frequency of a wavelet is r 2(exp -1), where r is display visual resolution in pixels/degree, and L is the wavelet level. Amplitude thresholds increase rapidly with spatial frequency. Thresholds also increase from Y to Cr to Cb, and with orientation from low-pass to horizontal/vertical to diagonal. We propose a mathematical model for DWT noise detection thresholds that is a function of level, orientation, and display visual resolution. This allows calculation of a 'perceptually lossless' quantization matrix for which all errors are in theory below the visual threshold. The model may also be used as the basis for adaptive quantization schemes.

  3. Free compression tube. Applications

    NASA Astrophysics Data System (ADS)

    Rusu, Ioan

    2012-11-01

    During the flight of vehicles, their propulsion energy must overcome gravity, to ensure the displacement of air masses on vehicle trajectory, to cover both energy losses from the friction between a solid surface and the air and also the kinetic energy of reflected air masses due to the impact with the flying vehicle. The flight optimization by increasing speed and reducing fuel consumption has directed research in the aerodynamics field. The flying vehicles shapes obtained through studies in the wind tunnel provide the optimization of the impact with the air masses and the airflow along the vehicle. By energy balance studies for vehicles in flight, the author Ioan Rusu directed his research in reducing the energy lost at vehicle impact with air masses. In this respect as compared to classical solutions for building flight vehicles aerodynamic surfaces which reduce the impact and friction with air masses, Ioan Rusu has invented a device which he named free compression tube for rockets, registered with the State Office for Inventions and Trademarks of Romania, OSIM, deposit f 2011 0352. Mounted in front of flight vehicles it eliminates significantly the impact and friction of air masses with the vehicle solid. The air masses come into contact with the air inside the free compression tube and the air-solid friction is eliminated and replaced by air to air friction.

  4. Processing digital video directly in the compressed domain has many advantages in terms of storage efficiency, speed,

    E-print Network

    Chang, Shih-Fu

    ABSTRACT Processing digital video directly in the compressed domain has many advantages in terms of storage efficiency, speed, and video quality. We have developed a compressed video editing and parsing. KEYWORDS Compressed domain video manipulation, client-server net- work based video editing, video content

  5. Vortex Stabilized Compressed Fusion Grade Plasma

    NASA Astrophysics Data System (ADS)

    Hershcovitch, Ady

    2015-03-01

    Inertial confinement fusion schemes comprise of highly compressed dense plasmas. Some involve short pulses of powerful beams (lasers, particles) applied to solid pellets, while others utilize plasma focus to obtain dense pinch plasmas. Although compression factor >1000 has been achieved for starting pressures in the Torr range, the latter is limited by instabilities for initial gas density above 10 Torr. One alternative approach could be shooting electron beams through very dense, atmospheric pressure, vortex stabilized plasma. Large azimuthal magnetic generated by an electron beam can compress and heat the plasma to fusion viable parameters. This configuration is stable against sausage, kink, or beam - plasma instabilities. Based on experimental evidence beam propagation through the plasma is not be an issue. A second possibility is to tangentially squeeze a quasi-neutral plasma focus flow by a surrounding gas vortex. Based on currently available electron beams, the first scheme viability as an electrical power generating reactor does not seem to be promising. But using a plasma cathode electron beam that was developed a while ago, for which DOE has a patent U.S. Patent 4,942,339, could result in net generation of electricity. Calculations will be presented. Work supported by Work supported under Contract No. DE-AC02-98CH1-886 with the US Department of Energy.

  6. Approximation and compression with sparse orthonormal transforms.

    PubMed

    Sezer, Osman Gokhan; Guleryuz, Onur G; Altunbasak, Yucel

    2015-08-01

    We propose a new transform design method that targets the generation of compression-optimized transforms for next-generation multimedia applications. The fundamental idea behind transform compression is to exploit regularity within signals such that redundancy is minimized subject to a fidelity cost. Multimedia signals, in particular images and video, are well known to contain a diverse set of localized structures, leading to many different types of regularity and to nonstationary signal statistics. The proposed method designs sparse orthonormal transforms (SOTs) that automatically exploit regularity over different signal structures and provides an adaptation method that determines the best representation over localized regions. Unlike earlier work that is motivated by linear approximation constructs and model-based designs that are limited to specific types of signal regularity, our work uses general nonlinear approximation ideas and a data-driven setup to significantly broaden its reach. We show that our SOT designs provide a safe and principled extension of the Karhunen-Loeve transform (KLT) by reducing to the KLT on Gaussian processes and by automatically exploiting non-Gaussian statistics to significantly improve over the KLT on more general processes. We provide an algebraic optimization framework that generates optimized designs for any desired transform structure (multiresolution, block, lapped, and so on) with significantly better n -term approximation performance. For each structure, we propose a new prototype codec and test over a database of images. Simulation results show consistent increase in compression and approximation performance compared with conventional methods. PMID:25823033

  7. Alternative Work Schedules in Office and Nonoffice Work Settings.

    ERIC Educational Resources Information Center

    Kirk, Raymond J.; Barton, H. David

    A rapidly growing change in the workplace is the replacement of a fixed work schedule with a variety of alternative work schedules (AWS), including both flexible and compressed schedules. Experimenting organizations (N=901) evaluated one of four major categories of AWS in office and nonoffice settings, i.e., a flexible 8-hour day;…

  8. Digital compression algorithms for HDTV transmission

    NASA Technical Reports Server (NTRS)

    Adkins, Kenneth C.; Shalkhauser, Mary JO; Bibyk, Steven B.

    1990-01-01

    Digital compression of video images is a possible avenue for high definition television (HDTV) transmission. Compression needs to be optimized while picture quality remains high. Two techniques for compression the digital images are explained and comparisons are drawn between the human vision system and artificial compression techniques. Suggestions for improving compression algorithms through the use of neural and analog circuitry are given.

  9. 76 FR 4338 - Research and Development Strategies for Compressed & Cryo-Compressed Hydrogen Storage Workshops

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-25

    ...Strategies for Compressed & Cryo- Compressed Hydrogen Storage Workshops AGENCY: Fuel Cell...Laboratory, in conjunction with the Hydrogen Storage team of the EERE Fuel Cell Technologies...workshops on compressed and cryo-compressed hydrogen storage in the Washington, DC...

  10. Compression and compression fatigue testing of composite laminates

    NASA Technical Reports Server (NTRS)

    Porter, T. R.

    1982-01-01

    The effects of moisture and temperature on the fatigue and fracture response of composite laminates under compression loads were investigated. The structural laminates studied were an intermediate stiffness graphite-epoxy composite (a typical angle ply laimna liminate had a typical fan blade laminate). Full and half penetration slits and impact delaminations were the defects examined. Results are presented which show the effects of moisture on the fracture and fatigue strength at room temperature, 394 K (250 F), and 422 K (300 F). Static tests results show the effects of defect size and type on the compression-fracture strength under moisture and thermal environments. The cyclic tests results compare the fatigue lives and residual compression strength under compression only and under tension-compression fatigue loading.

  11. Work Experience Guidance for Managers

    E-print Network

    Work Experience Guidance for Managers When approached with a request for work experience, managers any work, paid or unpaid: Before 7am or after 7pm For more than two hours on a school day or Sunday, they must have a two week break from any work during the school holiday For those aged between 16 and 17

  12. Detecting double compression of audio signal

    NASA Astrophysics Data System (ADS)

    Yang, Rui; Shi, Yun Q.; Huang, Jiwu

    2010-01-01

    MP3 is the most popular audio format nowadays in our daily life, for example music downloaded from the Internet and file saved in the digital recorder are often in MP3 format. However, low bitrate MP3s are often transcoded to high bitrate since high bitrate ones are of high commercial value. Also audio recording in digital recorder can be doctored easily by pervasive audio editing software. This paper presents two methods for the detection of double MP3 compression. The methods are essential for finding out fake-quality MP3 and audio forensics. The proposed methods use support vector machine classifiers with feature vectors formed by the distributions of the first digits of the quantized MDCT (modified discrete cosine transform) coefficients. Extensive experiments demonstrate the effectiveness of the proposed methods. To the best of our knowledge, this piece of work is the first one to detect double compression of audio signal.

  13. Tight and simple Web graph compression

    E-print Network

    Grabowski, Szymon

    2010-01-01

    Analysing Web graphs has applications in determining page ranks, fighting Web spam, detecting communities and mirror sites, and more. This study is however hampered by the necessity of storing a major part of huge graphs in the external memory, which prevents efficient random access to edge (hyperlink) lists. A number of algorithm involving compression techniques have thus been presented, to represent Web graphs succinctly but also providing random access. Those techniques are usually based on differential encodings of the adjacency lists, finding repeating nodes or node regions in the successive lists, more general grammar-based transformations or 2-dimensional representations of the binary matrix of the graph. In this paper we present two Web graph compression algorithms. The first can be seen as engineering of the Boldi and Vigna (2004) method. We extend the notion of similarity between link lists, and use a more compact encoding of residuals. The algorithm works on blocks of varying size (in the number of...

  14. Continuous-variable quantum compressed sensing

    E-print Network

    Matthias Ohliger; Vincent Nesme; David Gross; Yi-Kai Liu; Jens Eisert

    2012-07-09

    We significantly extend recently developed methods to faithfully reconstruct unknown quantum states that are approximately low-rank, using only a few measurement settings. Our new method is general enough to allow for measurements from a continuous family, and is also applicable to continuous-variable states. As a technical result, this work generalizes quantum compressed sensing to the situation where the measured observables are taken from a so-called tight frame (rather than an orthonormal basis) --- hence covering most realistic measurement scenarios. As an application, we discuss the reconstruction of quantum states of light from homodyne detection and other types of measurements, and we present simulations that show the advantage of the proposed compressed sensing technique over present methods. Finally, we introduce a method to construct a certificate which guarantees the success of the reconstruction with no assumption on the state, and we show how slightly more measurements give rise to "universal" state reconstruction that is highly robust to noise.

  15. Radiator debris removing apparatus and work machine using same

    DOEpatents

    Martin, Kevin L. (Washburn, IL); Elliott, Dwight E. (Chillicothe, IL)

    2008-09-02

    A radiator assembly includes a finned radiator core and a debris removing apparatus having a compressed air inlet and at least one compressed air outlet configured to direct compressed air through the radiator core. A work machine such as a wheel loader includes a radiator and a debris removing apparatus coupled with on-board compressed air and having at least one pressurized gas outlet configured to direct a gas toward the face of the radiator.

  16. Data compression by wavelet transforms

    NASA Technical Reports Server (NTRS)

    Shahshahani, M.

    1992-01-01

    A wavelet transform algorithm is applied to image compression. It is observed that the algorithm does not suffer from the blockiness characteristic of the DCT-based algorithms at compression ratios exceeding 25:1, but the edges do not appear as sharp as they do with the latter method. Some suggestions for the improved performance of the wavelet transform method are presented.

  17. Pressure Oscillations in Adiabatic Compression

    ERIC Educational Resources Information Center

    Stout, Roland

    2011-01-01

    After finding Moloney and McGarvey's modified adiabatic compression apparatus, I decided to insert this experiment into my physical chemistry laboratory at the last minute, replacing a problematic experiment. With insufficient time to build the apparatus, we placed a bottle between two thick textbooks and compressed it with a third textbook forced…

  18. "Noiseless" Data-Compression Algorithm

    NASA Technical Reports Server (NTRS)

    Rice, R. F.; Lee, J. J.

    1986-01-01

    Gamma-ray spectrometer data compressed to enable more frequent sampling. Proposed data-compression algorithm efficiently represents gamma-ray spectrometer spectra at any spectrum collection interval from 5 seconds to 5 minutes. Data representations "noiseless" (Data exactly constructed). Techniques useful in designing datacompression algorithms for other spectral instruments, which have varying data-rate requirements.

  19. Streaming Compression of Hexahedral Meshes

    SciTech Connect

    Isenburg, M; Courbet, C

    2010-02-03

    We describe a method for streaming compression of hexahedral meshes. Given an interleaved stream of vertices and hexahedral our coder incrementally compresses the mesh in the presented order. Our coder is extremely memory efficient when the input stream documents when vertices are referenced for the last time (i.e. when it contains topological finalization tags). Our coder then continuously releases and reuses data structures that no longer contribute to compressing the remainder of the stream. This means in practice that our coder has only a small fraction of the whole mesh in memory at any time. We can therefore compress very large meshes - even meshes that do not file in memory. Compared to traditional, non-streaming approaches that load the entire mesh and globally reorder it during compression, our algorithm trades a less compact compressed representation for significant gains in speed, memory, and I/O efficiency. For example, on the 456k hexahedra 'blade' mesh, our coder is twice as fast and uses 88 times less memory (only 3.1 MB) with the compressed file increasing about 3% in size. We also present the first scheme for predictive compression of properties associated with hexahedral cells.

  20. Application specific compression : final report.

    SciTech Connect

    Melgaard, David Kennett; Byrne, Raymond Harry; Myers, Daniel S.; Harrison, Carol D.; Lee, David S.; Lewis, Phillip J.; Carlson, Jeffrey J.

    2008-12-01

    With the continuing development of more capable data gathering sensors, comes an increased demand on the bandwidth for transmitting larger quantities of data. To help counteract that trend, a study was undertaken to determine appropriate lossy data compression strategies for minimizing their impact on target detection and characterization. The survey of current compression techniques led us to the conclusion that wavelet compression was well suited for this purpose. Wavelet analysis essentially applies a low-pass and high-pass filter to the data, converting the data into the related coefficients that maintain spatial information as well as frequency information. Wavelet compression is achieved by zeroing the coefficients that pertain to the noise in the signal, i.e. the high frequency, low amplitude portion. This approach is well suited for our goal because it reduces the noise in the signal with only minimal impact on the larger, lower frequency target signatures. The resulting coefficients can then be encoded using lossless techniques with higher compression levels because of the lower entropy and significant number of zeros. No significant signal degradation or difficulties in target characterization or detection were observed or measured when wavelet compression was applied to simulated and real data, even when over 80% of the coefficients were zeroed. While the exact level of compression will be data set dependent, for the data sets we studied, compression factors over 10 were found to be satisfactory where conventional lossless techniques achieved levels of less than 3.

  1. Compressive Network Analysis

    PubMed Central

    Jiang, Xiaoye; Yao, Yuan; Liu, Han; Guibas, Leonidas

    2014-01-01

    Modern data acquisition routinely produces massive amounts of network data. Though many methods and models have been proposed to analyze such data, the research of network data is largely disconnected with the classical theory of statistical learning and signal processing. In this paper, we present a new framework for modeling network data, which connects two seemingly different areas: network data analysis and compressed sensing. From a nonparametric perspective, we model an observed network using a large dictionary. In particular, we consider the network clique detection problem and show connections between our formulation with a new algebraic tool, namely Randon basis pursuit in homogeneous spaces. Such a connection allows us to identify rigorous recovery conditions for clique detection problems. Though this paper is mainly conceptual, we also develop practical approximation algorithms for solving empirical problems and demonstrate their usefulness on real-world datasets. PMID:25620806

  2. Compressibility of Nanocrystalline Forsterite

    SciTech Connect

    Couvy, H.; Chen, J; Drozd, V

    2010-01-01

    We established an equation of state for nanocrystalline forsterite using multi-anvil press and diamond anvil cell. Comparative high-pressure and high-temperature experiments have been performed up to 9.6 GPa and 1,300 C. We found that nanocrystalline forsterite is more compressible than macro-powder forsterite. The bulk modulus of nanocrystalline forsterite is equal to 123.3 ({+-}3.4) GPa whereas the bulk modulus of macro-powder forsterite is equal to 129.6 ({+-}3.2) GPa. This difference is attributed to a weakening of the elastic properties of grain boundary and triple junction and their significant contribution in nanocrystalline sample compare to the bulk counterpart. The bulk modulus at zero pressure of forsterite grain boundary was determined to be 83.5 GPa.

  3. Compressed quantum simulation

    SciTech Connect

    Kraus, B.

    2014-12-04

    Here, I summarize the results presented in B. Kraus, Phys. Rev. Lett. 107, 250503 (2011). Recently, it has been shown that certain circuits, the so-called match gate circuits, can be compressed to an exponentially smaller universal quantum computation. We use this result to demonstrate that the simulation of a 1-D Ising chain consisting of n qubits can be performed on a universal quantum computer running on only log(n) qubits. We show how the adiabatic evolution can be simulated on this exponentially smaller system and how the magnetization can be measured. Since the Ising model displays a quantum phase transition, this result implies that a quantum phase transition of a very large system can be observed with current technology.

  4. Edge compression manifold apparatus

    DOEpatents

    Renzi, Ronald F.

    2004-12-21

    A manifold for connecting external capillaries to the inlet and/or outlet ports of a microfluidic device for high pressure applications is provided. The fluid connector for coupling at least one fluid conduit to a corresponding port of a substrate that includes: (i) a manifold comprising one or more channels extending therethrough wherein each channel is at least partially threaded, (ii) one or more threaded ferrules each defining a bore extending therethrough with each ferrule supporting a fluid conduit wherein each ferrule is threaded into a channel of the manifold, (iii) a substrate having one or more ports on its upper surface wherein the substrate is positioned below the manifold so that the one or more ports is aligned with the one or more channels of the manifold, and (iv) device to apply an axial compressive force to the substrate to couple the one or more ports of the substrate to a corresponding proximal end of a fluid conduit.

  5. Population attribute compression

    DOEpatents

    White, James M. (Los Alamos, NM); Faber, Vance (Los Alamos, NM); Saltzman, Jeffrey S. (Los Alamos, NM)

    1995-01-01

    An image population having a large number of attributes is processed to form a display population with a predetermined smaller number of attributes that represent the larger number of attributes. In a particular application, the color values in an image are compressed for storage in a discrete look-up table (LUT). Color space containing the LUT color values is successively subdivided into smaller volumes until a plurality of volumes are formed, each having no more than a preselected maximum number of color values. Image pixel color values can then be rapidly placed in a volume with only a relatively few LUT values from which a nearest neighbor is selected. Image color values are assigned 8 bit pointers to their closest LUT value whereby data processing requires only the 8 bit pointer value to provide 24 bit color values from the LUT.

  6. Vapor compression distillation module

    NASA Technical Reports Server (NTRS)

    Nuccio, P. P.

    1975-01-01

    A Vapor Compression Distillation (VCD) module was developed and evaluated as part of a Space Station Prototype (SSP) environmental control and life support system. The VCD module includes the waste tankage, pumps, post-treatment cells, automatic controls and fault detection instrumentation. Development problems were encountered with two components: the liquid pumps, and the waste tank and quantity gauge. Peristaltic pumps were selected instead of gear pumps, and a sub-program of materials and design optimization was undertaken leading to a projected life greater than 10,000 hours of continuous operation. A bladder tank was designed and built to contain the waste liquids and deliver it to the processor. A detrimental pressure pattern imposed upon the bladder by a force-operated quantity gauge was corrected by rearranging the force application, and design goals were achieved. System testing has demonstrated that all performance goals have been fulfilled.

  7. Understanding the Basics of Compressed Air Systems 

    E-print Network

    Herron, D. J.

    1997-01-01

    Compressed air can be a manufacturing facilities' most expensive utility. Estimates and actual measurements of compressed air systems indicate ten to thirty-five percent of all compressed air generated is lost to leakage or improper use. Proper...

  8. Advanced Controls for Industrial Compressed Air Systems 

    E-print Network

    Vold, P.; Gabel, S.; Carmichael, L.; Curtner, K.; Cirillo, N. C. Jr.

    1997-01-01

    An integrated solution to control compressed air systems has been developed which significantly improves the quality of the compressed air, while decreasing operating expenses. Honeywell's XCEED™ compressed air system solution has been installed...

  9. Characterizing Perceptual Artifacts in Compressed Video Streams

    E-print Network

    Wang, Zhou

    Characterizing Perceptual Artifacts in Compressed Video Streams Kai Zeng, Tiesong Zhao, Abdul important roles in the development of effective video compression, streaming and quality enhancement systems of novel coding structures and strategies during the development of new video compression standards

  10. Manipulating lossless video in the compressed domain

    E-print Network

    Thies, William

    A compressed-domain transformation is one that operates directly on the compressed format, rather than requiring conversion to an uncompressed format prior to processing. Performing operations in the compressed domain ...

  11. Chirp Sensing Codes: Deterministic Compressed Sensing Measurements

    E-print Network

    Chirp Sensing Codes: Deterministic Compressed Sensing Measurements for Fast Recovery Lorne Abstract--Compressed sensing is a novel technique to acquire sparse signals with few measurements. Normally, compressed sensing uses random projections as measurements. Here we de- sign deterministic measurements

  12. Adult Learners' Week in Russia.

    ERIC Educational Resources Information Center

    Litvinova, Nina

    2002-01-01

    In Russia International Adult Learners Week highlights the democratization process the country is undergoing. Government attention to rural development and training and agrarian policy is needed. (SK)

  13. Studies on image compression and image reconstruction

    NASA Technical Reports Server (NTRS)

    Sayood, Khalid; Nori, Sekhar; Araj, A.

    1994-01-01

    During this six month period our works concentrated on three, somewhat different areas. We looked at and developed a number of error concealment schemes for use in a variety of video coding environments. This work is described in an accompanying (draft) Masters thesis. In the thesis we describe application of this techniques to the MPEG video coding scheme. We felt that the unique frame ordering approach used in the MPEG scheme would be a challenge to any error concealment/error recovery technique. We continued with our work in the vector quantization area. We have also developed a new type of vector quantizer, which we call a scan predictive vector quantization. The scan predictive VQ was tested on data processed at Goddard to approximate Landsat 7 HRMSI resolution and compared favorably with existing VQ techniques. A paper describing this work is included. The third area is concerned more with reconstruction than compression. While there is a variety of efficient lossless image compression schemes, they all have a common property that they use past data to encode future data. This is done either via taking differences, context modeling, or by building dictionaries. When encoding large images, this common property becomes a common flaw. When the user wishes to decode just a portion of the image, the requirement that the past history be available forces the decoding of a significantly larger portion of the image than desired by the user. Even with intelligent partitioning of the image dataset, the number of pixels decoded may be four times the number of pixels requested. We have developed an adaptive scanning strategy which can be used with any lossless compression scheme and which lowers the additional number of pixels to be decoded to about 7 percent of the number of pixels requested! A paper describing these results is included.

  14. Proceedings of the Communications Theory MiniConference at GLOBECOM '94, San Francisco, California, pp. 120--126 A TESBASED MODEL FOR COMPRESSED

    E-print Network

    , pp. 120--126 A TES­BASED MODEL FOR COMPRESSED ``STAR WARS'' VIDEO BENJAMIN MELAMED NEC USA Inc. 4 of the entire ``Star Wars'' movie under a JPEG­like compression. The goal of this work is to develop

  15. FIG Working Week 2015 1 THE VISIBLE BOUNDARY

    E-print Network

    rural land reform 9. Improve urban planning and infrastructure development 10. Produce statistical data Percentage Linked to inheritance 157 41.2 Eviction by gov. agency 83 21.8 Boundary 81 21.3 Eviction

  16. Advances in compressible turbulent mixing

    SciTech Connect

    Dannevik, W.P.; Buckingham, A.C.; Leith, C.E.

    1992-01-01

    This volume includes some recent additions to original material prepared for the Princeton International Workshop on the Physics of Compressible Turbulent Mixing, held in 1988. Workshop participants were asked to emphasize the physics of the compressible mixing process rather than measurement techniques or computational methods. Actual experimental results and their meaning were given precedence over discussions of new diagnostic developments. Theoretical interpretations and understanding were stressed rather than the exposition of new analytical model developments or advances in numerical procedures. By design, compressibility influences on turbulent mixing were discussed--almost exclusively--from the perspective of supersonic flow field studies. The papers are arranged in three topical categories: Foundations, Vortical Domination, and Strongly Coupled Compressibility. The Foundations category is a collection of seminal studies that connect current study in compressible turbulent mixing with compressible, high-speed turbulent flow research that almost vanished about two decades ago. A number of contributions are included on flow instability initiation, evolution, and transition between the states of unstable flow onset through those descriptive of fully developed turbulence. The Vortical Domination category includes theoretical and experimental studies of coherent structures, vortex pairing, vortex-dynamics-influenced pressure focusing. In the Strongly Coupled Compressibility category the organizers included the high-speed turbulent flow investigations in which the interaction of shock waves could be considered an important source for production of new turbulence or for the enhancement of pre-existing turbulence. Individual papers are processed separately.

  17. Best compression: Reciprocating or rotary?

    SciTech Connect

    Cahill, C.

    1997-07-01

    A compressor is a device used to increase the pressure of a compressible fluid. The inlet pressure can vary from a deep vacuum to a high positive pressure. The discharge pressure can range from subatmospheric levels to tens of thousands of pounds per square inch. Compressors come in numerous forms, but for oilfield applications there are two primary types, reciprocating and rotary. Both reciprocating and rotary compressors are grouped in the intermittent mode of compression. Intermittent is cyclic in nature, in that a specific quantity of gas is ingested by the compressor, acted upon and discharged before the cycle is repeated. Reciprocating compression is the most common form of compression used for oilfield applications. Rotary screw compressors have a long history but are relative newcomers to oilfield applications. The rotary screw compressor-technically a helical rotor compressor-dates back to 1878. That was when the first rotary screw was manufactured for the purpose of compressing air. Today thousands of rotary screw compression packages are being used throughout the world to compress natural gas.

  18. Data compression applied to HHVT

    NASA Technical Reports Server (NTRS)

    Thompson, William K.

    1990-01-01

    A task order was written by the High Resolution, High Frame Rate Video Technology (HHVT) project engineers to study data compression techniques that could be applied to the HHVT system. Specifically, the goals of the HHVT data compression study are to accomplish the following: (1) Determine the downlink capabilities of the Space Shuttle and Space Station Freedom to support HHVT data (i.e., determine the maximum data rates and link availability); (2) Determine current and projected capabilities of high speed storage media to support HHVT data by determining their maximum data acquisition/transmission rates and volumes; (3) Identify which experiment in the HHVT Users' Requirement data base need data compression, based on the experiments' imaging requirements; (4) Select the best data compression technique for each of these users by identifying a technique that provides compression but minimizes distortion; and (5) Investigate state-of-the-art technologies for possible implementation of selected data compression techniques. Data compression will be needed because of the high data rates and larger volumes of data that will result from the use of digitized video onboard the Space Shuttle and Space Station Freedom.

  19. Multi-shot compressed coded aperture imaging

    NASA Astrophysics Data System (ADS)

    Shao, Xiaopeng; Du, Juan; Wu, Tengfei; Jin, Zhenhua

    2013-09-01

    The classical methods of compressed coded aperture (CCA) still require an optical sensor with high resolution, although the sampling rate has broken the Nyquist sampling rate already. A novel architecture of multi-shot compressed coded aperture imaging (MCCAI) using a low resolution optical sensor is proposed, which is mainly based on the 4-f imaging system, combining with two spatial light modulators (SLM) to achieve the compressive imaging goal. The first SLM employed for random convolution is placed at the frequency spectrum plane of the 4-f imaging system, while the second SLM worked as a selecting filter is positioned in front of the optical sensor. By altering the random coded pattern of the second SLM and sampling, a couple of observations can be obtained by a low resolution optical sensor easily, and these observations will be combined mathematically and used to reconstruct the high resolution image. That is to say, MCCAI aims at realizing the super resolution imaging with multiple random samplings by using a low resolution optical sensor. To improve the computational imaging performance, total variation (TV) regularization is introduced into the super resolution reconstruction model to get rid of the artifacts, and alternating direction method of multipliers (ADM) is utilized to solve the optimal result efficiently. The results show that the MCCAI architecture is suitable for super resolution computational imaging using a much lower resolution optical sensor than traditional CCA imaging methods by capturing multiple frame images.

  20. Estimating JPEG2000 compression for image forensics using Benford's Law

    NASA Astrophysics Data System (ADS)

    Qadir, Ghulam; Zhao, Xi; Ho, Anthony T. S.

    2010-05-01

    With the tremendous growth and usage of digital images nowadays, the integrity and authenticity of digital content is becoming increasingly important, and a growing concern to many government and commercial sectors. Image Forensics, based on a passive statistical analysis of the image data only, is an alternative approach to the active embedding of data associated with Digital Watermarking. Benford's Law was first introduced to analyse the probability distribution of the 1st digit (1-9) numbers of natural data, and has since been applied to Accounting Forensics for detecting fraudulent income tax returns [9]. More recently, Benford's Law has been further applied to image processing and image forensics. For example, Fu et al. [5] proposed a Generalised Benford's Law technique for estimating the Quality Factor (QF) of JPEG compressed images. In our previous work, we proposed a framework incorporating the Generalised Benford's Law to accurately detect unknown JPEG compression rates of watermarked images in semi-fragile watermarking schemes. JPEG2000 (a relatively new image compression standard) offers higher compression rates and better image quality as compared to JPEG compression. In this paper, we propose the novel use of Benford's Law for estimating JPEG2000 compression for image forensics applications. By analysing the DWT coefficients and JPEG2000 compression on 1338 test images, the initial results indicate that the 1st digit probability of DWT coefficients follow the Benford's Law. The unknown JPEG2000 compression rates of the image can also be derived, and proved with the help of a divergence factor, which shows the deviation between the probabilities and Benford's Law. Based on 1338 test images, the mean divergence for DWT coefficients is approximately 0.0016, which is lower than DCT coefficients at 0.0034. However, the mean divergence for JPEG2000 images compression rate at 0.1 is 0.0108, which is much higher than uncompressed DWT coefficients. This result clearly indicates a presence of compression in the image. Moreover, we compare the results of 1st digit probability and divergence among JPEG2000 compression rates at 0.1, 0.3, 0.5 and 0.9. The initial results show that the expected difference among them could be used for further analysis to estimate the unknown JPEG2000 compression rates.

  1. Personal Tutor Agenda Fourth Week

    E-print Network

    Personal Tutor Agenda Fourth Week - Each Personal Tutor arranges a meeting with students who were assigned to him/her to receive their notes, concerns and get acquainted with their problems. Personal tutor to the Quality Committee. The meeting should take place before the end of the fifth week. - Each Personal Tutor

  2. Evolution of some Los Alamos flux compression programs

    SciTech Connect

    Fowler, C.M.; Goforth, J.H.

    1996-12-31

    When we were approached to give a general discussion of some aspects of the Los Alamos flux compression program, we decided to present historical backgrounds of a few topics that have some relevance to programs that we very much In the forefront of activities going on today. Of some thirty abstracts collected at Los Alamos for this conference, ten of them dealt with electromagnetic acceleration of materials, notably the compression of heavy liners, and five dealt with plasma compression. Both of these topics have been under investigation, off and on, from the time a formal flux compression program was organized at Los Alamos. We decided that a short overview of work done In these areas would be of some interest. Some of the work described below has been discussed in Laboratory reports that, while referenced and available, are not readily accessible. For completeness, some previously published, accessible work Is also discussed but much more briefly. Perhaps the most striking thing about the early work In these two areas is how primitive much of it was when compared to the far more sophisticated, related activities of today. Another feature of these programs, actually for most programs, Is their cyclic nature. Their relevance and/or funding seems to come land go. Eventually, many of the older programs come back into favor. Activities Involving the dense plasma focus (DPF), about which some discussions will be given later, furnish a classic example of this kind, coming Into and then out of periods of heightened interest. We devote the next two sections of this paper to a review of our work In magnetic acceleration of solids and of plasma compression. A final section gives a survey of our work In which thin foils are imploded to produce intense quantities of son x-rays. The authors are well aware of much excellent work done elsewhere In all of these topics, but partly because of space limitations, have confined this discussion to work done at Los Alamos.

  3. The OMV Data Compression System Science Data Compression Workshop

    NASA Technical Reports Server (NTRS)

    Lewis, Garton H., Jr.

    1989-01-01

    The Video Compression Unit (VCU), Video Reconstruction Unit (VRU), theory and algorithms for implementation of Orbital Maneuvering Vehicle (OMV) source coding, docking mode, channel coding, error containment, and video tape preprocessed space imagery are presented in viewgraph format.

  4. Making Compressed Air System Decisions 

    E-print Network

    Porri, R. E.

    1996-01-01

    stream_source_info ESL-IE-96-04-32.pdf.txt stream_content_type text/plain stream_size 5121 Content-Encoding ISO-8859-1 stream_name ESL-IE-96-04-32.pdf.txt Content-Type text/plain; charset=ISO-8859-1 MAKING COMPRESSED AIR... SYSTEM DECISIONS Richard E. Porri Product Manager ABSTRACT This paper presents a decision making process that will pennit the design, installation and operation ofa high efficiency and reliable compressed air system. The design of a compressed air...

  5. Compressive adaptive computational ghost imaging

    PubMed Central

    A?mann, Marc; Bayer, Manfred

    2013-01-01

    Compressive sensing is considered a huge breakthrough in signal acquisition. It allows recording an image consisting of N2 pixels using much fewer than N2 measurements if it can be transformed to a basis where most pixels take on negligibly small values. Standard compressive sensing techniques suffer from the computational overhead needed to reconstruct an image with typical computation times between hours and days and are thus not optimal for applications in physics and spectroscopy. We demonstrate an adaptive compressive sampling technique that performs measurements directly in a sparse basis. It needs much fewer than N2 measurements without any computational overhead, so the result is available instantly. PMID:23529046

  6. Designing experiments through compressed sensing.

    SciTech Connect

    Young, Joseph G.; Ridzal, Denis

    2013-06-01

    In the following paper, we discuss how to design an ensemble of experiments through the use of compressed sensing. Specifically, we show how to conduct a small number of physical experiments and then use compressed sensing to reconstruct a larger set of data. In order to accomplish this, we organize our results into four sections. We begin by extending the theory of compressed sensing to a finite product of Hilbert spaces. Then, we show how these results apply to experiment design. Next, we develop an efficient reconstruction algorithm that allows us to reconstruct experimental data projected onto a finite element basis. Finally, we verify our approach with two computational experiments.

  7. Impact of lossy compression on diagnostic accuracy of radiographs for periapical lesions

    NASA Technical Reports Server (NTRS)

    Eraso, Francisco E.; Analoui, Mostafa; Watson, Andrew B.; Rebeschini, Regina

    2002-01-01

    OBJECTIVES: The purpose of this study was to evaluate the lossy Joint Photographic Experts Group compression for endodontic pretreatment digital radiographs. STUDY DESIGN: Fifty clinical charge-coupled device-based, digital radiographs depicting periapical areas were selected. Each image was compressed at 2, 4, 8, 16, 32, 48, and 64 compression ratios. One root per image was marked for examination. Images were randomized and viewed by four clinical observers under standardized viewing conditions. Each observer read the image set three times, with at least two weeks between each reading. Three pre-selected sites per image (mesial, distal, apical) were scored on a five-scale score confidence scale. A panel of three examiners scored the uncompressed images, with a consensus score for each site. The consensus score was used as the baseline for assessing the impact of lossy compression on the diagnostic values of images. The mean absolute error between consensus and observer scores was computed for each observer, site, and reading session. RESULTS: Balanced one-way analysis of variance for all observers indicated that for compression ratios 48 and 64, there was significant difference between mean absolute error of uncompressed and compressed images (P <.05). After converting the five-scale score to two-level diagnostic values, the diagnostic accuracy was strongly correlated (R (2) = 0.91) with the compression ratio. CONCLUSION: The results of this study suggest that high compression ratios can have a severe impact on the diagnostic quality of the digital radiographs for detection of periapical lesions.

  8. Inflammatory cascades mediate synapse elimination in spinal cord compression

    PubMed Central

    2014-01-01

    Background Cervical compressive myelopathy (CCM) is caused by chronic spinal cord compression due to spondylosis, a degenerative disc disease, and ossification of the ligaments. Tip-toe walking Yoshimura (twy) mice are reported to be an ideal animal model for CCM-related neuronal dysfunction, because they develop spontaneous spinal cord compression without any artificial manipulation. Previous histological studies showed that neurons are lost due to apoptosis in CCM, but the mechanism underlying this neurodegeneration was not fully elucidated. The purpose of this study was to investigate the pathophysiology of CCM by evaluating the global gene expression of the compressed spinal cord and comparing the transcriptome analysis with the physical and histological findings in twy mice. Methods Twenty-week-old twy mice were divided into two groups according to the magnetic resonance imaging (MRI) findings: a severe compression (S) group and a mild compression (M) group. The transcriptome was analyzed by microarray and RT-PCR. The cellular pathophysiology was examined by immunohistological analysis and immuno-electron microscopy. Motor function was assessed by Rotarod treadmill latency and stride-length tests. Results Severe cervical calcification caused spinal canal stenosis and low functional capacity in twy mice. The microarray analysis revealed 215 genes that showed significantly different expression levels between the S and the M groups. Pathway analysis revealed that genes expressed at higher levels in the S group were enriched for terms related to the regulation of inflammation in the compressed spinal cord. M1 macrophage-dominant inflammation was present in the S group, and cysteine-rich protein 61 (Cyr61), an inducer of M1 macrophages, was markedly upregulated in these spinal cords. Furthermore, C1q, which initiates the classical complement cascade, was more upregulated in the S group than in the M group. The confocal and electron microscopy observations indicated that classically activated microglia/macrophages had migrated to the compressed spinal cord and eliminated synaptic terminals. Conclusions We revealed the detailed pathophysiology of the inflammatory response in an animal model of chronic spinal cord compression. Our findings suggest that complement-mediated synapse elimination is a central mechanism underlying the neurodegeneration in CCM. PMID:24589419

  9. Compression relief engine brake

    SciTech Connect

    Meneely, V.A.

    1987-10-06

    A compression relief brake is described for four cycle internal-combustion engines, comprising: a pressurized oil supply; means for selectively pressurizing a hydraulic circuit with oil from the oil supply; a master piston and cylinder communicating with a slave piston and cylinder via the hydraulic circuit; an engine exhaust valve mechanically coupled to the engine and timed to open during the exhaust cycle of the engine the exhaust valve coupled to the slave piston. The exhaust valve is spring-based in a closed state to contact a valve seat; a sleeve frictionally and slidably disposed within a cavity defined by the slave piston which cavity communicates with the hydraulic circuit. When the hydraulic circuit is selectively pressurized and the engine is operating the sleeve entraps an incompressible volume of oil within the cavity to generate a displacement of the slave piston within the slave cylinder, whereby a first gap is maintained between the exhaust valve and its associated seat; and means for reciprocally activating the master piston for increasing the pressure within the previously pressurized hydraulic circuit during at least a portion of the expansion cycle of the engine whereby a second gap is reciprocally maintained between the exhaust valve and its associated seat.

  10. Gradient Compression Stockings may Prevent Recovery after Bed Rest Deconditioning

    NASA Technical Reports Server (NTRS)

    Stenger, Michael B.; Lee, Stuart M.; Westby, Christian M.; Willig, Michael C.; Platts, Steven H.

    2011-01-01

    Introduction: Astronauts continue to wear a compression garment during and immediately after landing to prevent orthostatic intolerance (OI). We recently developed a custom-fitted, 3-piece garment that consists of thigh-high stockings with biker-style shorts that provides continuous, gradient compression: 55 mmHg at the ankle that decreases to approximately 20 mmHg at the top of the leg and 15 mmHg over the abdomen. This garment has been shown to be effective in preventing symptoms of OI during a short stand test after Space Shuttle missions, but symptoms may persist for several days after a long-duration mission in some astronauts. The purpose of this study was to confirm the effectiveness of wearing these elastic, gradient compression garments during orthostatic testing after 2 weeks of 6 degree head-down tilt bed rest as a model of spaceflight and to determine whether they would impact recovery after bed rest. Methods: Eight (5 treatment, 3 control) of 16 subjects have completed this study to-date. All subjects wore the 3-piece garment from waking until tilt testing (3 h) as a simulation of the timeline for astronauts on landing day (BR+0). Control subjects removed the garment after the tilt test. Treatment subjects wore the garment for the remainder of the day and wore lower compression thigh-high only garments on the day after bed rest (BR+1). Blood pressure, heart rate, and stroke volume responses to a 15-min 80 degree head-up tilt test were determined before 2 weeks of 6 degree head-down tilt, and on BR+0 and BR+1. Plasma volume (PV) was measured before each of these test sessions. Data are mean SE. Results: Compression garments prevented signs of OI on BR+0; all subjects in both groups completed the full 15-min test. Heart rate responses to tilt were lower on BR+0 than all other test days. Control subjects demonstrated a marginal PV decrease after bed rest, but showed typical recovery the day after bed rest (BR+0: 2.32 plus or minus 0.15 L to BR+1: 2.79 plus or minus 0.15 L). Treatment subjects did not recover PV the day after bed rest (BR+0: 2.61 plus or minus 0.23 L to BR+1: 2.61 plus or minus 0.23 L). Conclusion: Abdomen-high compression garments, which are effective in preventing post-bed rest orthostatic intolerance, may slow recovery of PV. Modified garments with reduced compression may be necessary to prevent prolonging recovery.

  11. Diagnoses of coaxial probes in shock compression.

    PubMed

    Sun, Yue; Ci, Jiaxiang; Yi, Pengfei; Zhang, Hongrun

    2009-06-01

    A miniature diagnostic apparatus, which consists of a target, a guiding tube, a nail-gun, and a simple base, has been developed in the proposed research to estimate batches of pinlike coaxial probes with selectable collision speeds, 198.3, 361.0, and 420.6 mps, corresponding to thrust capabilities of certain minibullets. This work aims at filling the gap between typical two stage light gas gun (>500 mps) and pendulum machine (<100 mps) with low cost and risk in realistic shock compressions. As a part of the experiment, the kappa coefficient and the statistical agreement and reliability are all evaluated. PMID:19566210

  12. Symmetric Toeplitz-Structured Compressed Sensing Matrices

    NASA Astrophysics Data System (ADS)

    Huang, Tao; Fan, Yi-Zheng; Zhu, Ming

    2015-11-01

    How to construct a suitable measurement matrix is an important topic in compressed sensing. A significant part of the recent work is that the measurement matrices are not completely random on the entries but exhibit some considerable structures. In this paper, we proved that a symmetric Toeplitz matrix and its variant can be used as measurement matrices and recovery signal with high probability. Compared with random matrices (e.g. Gaussian and Bernoulli matrices) and some structured matrices (e.g. Toeplitz and circulant matrices), we need to generate fewer independent entries to obtain the measurement matrix while the effectiveness of the recovery keeps good.

  13. Görtler vortices in compressible mixing layers

    NASA Astrophysics Data System (ADS)

    Sarkies, J. M.; Otto, S. R.

    2001-01-01

    In experiments, Plesniak, Mehta & Johnson (1994) have noted that curved two-stream mixing layers are susceptible to centrifugal instabilities under the condition that the slower of the streams curves towards the faster one; this condition is analogous to the concave curvature condition for the stability of the flow over a plate. The modes which arise manifest themselves as vortices aligned with the dominant flow direction. Previous numerical and analytical work has elucidated the structure of these vortices within incompressible mixing layers; Otto, Jackson & Hu (1996). In this paper we go on to investigate the rôles of compressibility and heating in determining the streamwise fate of Görtler vortices within these situations.

  14. Diagnoses of coaxial probes in shock compression

    NASA Astrophysics Data System (ADS)

    Sun, Yue; Ci, Jiaxiang; Yi, Pengfei; Zhang, Hongrun

    2009-06-01

    A miniature diagnostic apparatus, which consists of a target, a guiding tube, a nail-gun, and a simple base, has been developed in the proposed research to estimate batches of pinlike coaxial probes with selectable collision speeds, 198.3, 361.0, and 420.6 mps, corresponding to thrust capabilities of certain minibullets. This work aims at filling the gap between typical two stage light gas gun (>500 mps) and pendulum machine (<100 mps) with low cost and risk in realistic shock compressions. As a part of the experiment, the ? coefficient and the statistical agreement and reliability are all evaluated.

  15. Journal of Nam Nguyen for Fall 08-09 1 Week of Sept 23th

    E-print Network

    Mohlenkamp, Martin J.

    had 2D pictures before. This week the Set group worked on finding how to implement a GUI with Python graphic things with Python. We also look for some free tools for user interacting graphic design. 2 Week of Oct 1st , 2008 Last week, I combined all of the buttons needed for the Set group in a single GUI

  16. 3 CFR 8365 - Proclamation 8365 of April 24, 2009. National Crime Victims’ Rights Week, 2009

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...National Crime Victimsâ Rights Week, 2009 8365 Proclamation...National Crime Victims’ Rights Week, 2009By the President...National Crime Victims’ Rights Week, we honor crime...supporting the men and women working every day to reduce...themselves in harm’s way and...

  17. SCADA Protocol Anomaly Detection Utilizing Compression (SPADUC) 2013

    SciTech Connect

    Gordon Rueff; Lyle Roybal; Denis Vollmer

    2013-01-01

    There is a significant need to protect the nation’s energy infrastructures from malicious actors using cyber methods. Supervisory, Control, and Data Acquisition (SCADA) systems may be vulnerable due to the insufficient security implemented during the design and deployment of these control systems. This is particularly true in older legacy SCADA systems that are still commonly in use. The purpose of INL’s research on the SCADA Protocol Anomaly Detection Utilizing Compression (SPADUC) project was to determine if and how data compression techniques could be used to identify and protect SCADA systems from cyber attacks. Initially, the concept was centered on how to train a compression algorithm to recognize normal control system traffic versus hostile network traffic. Because large portions of the TCP/IP message traffic (called packets) are repetitive, the concept of using compression techniques to differentiate “non-normal” traffic was proposed. In this manner, malicious SCADA traffic could be identified at the packet level prior to completing its payload. Previous research has shown that SCADA network traffic has traits desirable for compression analysis. This work investigated three different approaches to identify malicious SCADA network traffic using compression techniques. The preliminary analyses and results presented herein are clearly able to differentiate normal from malicious network traffic at the packet level at a very high confidence level for the conditions tested. Additionally, the master dictionary approach used in this research appears to initially provide a meaningful way to categorize and compare packets within a communication channel.

  18. A new compression format for fiber tracking datasets.

    PubMed

    Presseau, Caroline; Jodoin, Pierre-Marc; Houde, Jean-Christophe; Descoteaux, Maxime

    2015-04-01

    A single diffusion MRI streamline fiber tracking dataset may contain hundreds of thousands, and often millions of streamlines and can take up to several gigabytes of memory. This amount of data is not only heavy to compute, but also difficult to visualize and hard to store on disk (especially when dealing with a collection of brains). These problems call for a fiber-specific compression format that simplifies its manipulation. As of today, no fiber compression format has yet been adopted and the need for it is now becoming an issue for future connectomics research. In this work, we propose a new compression format, .zfib, for streamline tractography datasets reconstructed from diffusion magnetic resonance imaging (dMRI). Tracts contain a large amount of redundant information and are relatively smooth. Hence, they are highly compressible. The proposed method is a processing pipeline containing a linearization, a quantization and an encoding step. Our pipeline is tested and validated under a wide range of DTI and HARDI tractography configurations (step size, streamline number, deterministic and probabilistic tracking) and compression options. Similar to JPEG, the user has one parameter to select: a worst-case maximum tolerance error in millimeter (mm). Overall, we find a compression factor of more than 96% for a maximum error of 0.1mm without any perceptual change or change of diffusion statistics (mean fractional anisotropy and mean diffusivity) along bundles. This opens new opportunities for connectomics and tractometry applications. PMID:25592997

  19. Freezing of liquid water under combined compression and electric fields

    NASA Astrophysics Data System (ADS)

    Stafford, S.; Bland, S.; Dolan, D.; Eakins, D.; Institute of Shock Physics Collaboration; Sandia National Labs Collaboration

    2013-06-01

    The melt curves of materials hold rich information concerning phase stability, coexistence, and other kinetics, typically studied through heating and cooling. Compression-induced solidification exposes new kinetics, yet is a practical challenge due to adiabatic heating. Water has a large heat capacity and many solid phases, making it a good candidate for compression freezing. Optical transmission measurements and high-speed imaging have demonstrated that water can freeze on nanosecond time scales. Being highly polar, freezing in water is strongly influenced by electric fields at atmospheric pressure. However, the role of external electric fields in freezing has yet to be determined at high pressure. We present experimental and theoretical results from our attempts to transform liquid water into solid ice under rapid compression. To minimize heating, samples are quasi-isentropically compressed via multiple shock or ramp wave compression. An external electric field applied to the sample imparts local order to the system, influencing solidification onset and growth. Classical molecular dynamic simulations show significant ordering effects at V/nm field strength, well above the dielectric strength of water. We present work that to address this issue. Freezing of liquid water under combined compression and electric fields.

  20. Compressed Gas Cylinder Process Reference Guide Approved by: Tony Gutterman Last Revised: 1/15/14

    E-print Network

    within compressed gas cylinders can be toxic, flammable, oxidizing, corrosive, inert, or some combination they are empty is an acceptable business practice as the expense of holding on to it could outweigh the benefit every couple days/weeks on different jobs appears to make business sense. · Holding onto a partially

  1. Geometric Compression Through Topological Surgery

    E-print Network

    Rossignac, Jarek

    use, and the exploitation of the Internet to distribute and share 3-D data have intensified the need-through, and electronic mock-up applications involving complex CAD models. In comparison to image and video compression

  2. Compressed Air Audits using AIRMaster 

    E-print Network

    Wheeler, G. M.; McGill, R. D.; Bessey, E. G.; Vischer, K.

    1997-01-01

    Air compressors are a significant industrial energy user and therefore a prime target for industrial energy audits. The project goal was to develop a software tool, AIRMaster, and supporting methodology for performing compressed air system audits...

  3. Compressed gas fuel storage system

    DOEpatents

    Wozniak, John J. (Columbia, MD); Tiller, Dale B. (Lincoln, NE); Wienhold, Paul D. (Baltimore, MD); Hildebrand, Richard J. (Edgemere, MD)

    2001-01-01

    A compressed gas vehicle fuel storage system comprised of a plurality of compressed gas pressure cells supported by shock-absorbing foam positioned within a shape-conforming container. The container is dimensioned relative to the compressed gas pressure cells whereby a radial air gap surrounds each compressed gas pressure cell. The radial air gap allows pressure-induced expansion of the pressure cells without resulting in the application of pressure to adjacent pressure cells or physical pressure to the container. The pressure cells are interconnected by a gas control assembly including a thermally activated pressure relief device, a manual safety shut-off valve, and means for connecting the fuel storage system to a vehicle power source and a refueling adapter. The gas control assembly is enclosed by a protective cover attached to the container. The system is attached to the vehicle with straps to enable the chassis to deform as intended in a high-speed collision.

  4. Comparison of Artificial Compressibility Methods

    NASA Technical Reports Server (NTRS)

    Kiris, Cetin; Housman, Jeffrey; Kwak, Dochan

    2004-01-01

    Various artificial compressibility methods for calculating the three-dimensional incompressible Navier-Stokes equations are compared. Each method is described and numerical solutions to test problems are conducted. A comparison based on convergence behavior, accuracy, and robustness is given.

  5. High compression rate text summarization

    E-print Network

    Branavan, Satchuthananthavale Rasiah Kuhan

    2008-01-01

    This thesis focuses on methods for condensing large documents into highly concise summaries, achieving compression rates on par with human writers. While the need for such summaries in the current age of information overload ...

  6. Compression fractures of the back

    MedlinePLUS

    ... Meirhaeghe J, et al. Efficacy and safety of balloon kyphoplasty compared with non-surgical care for vertebral compression fracture (FREE): a randomised controlled trial. Lancet . 2009;373(9668):1016-24.

  7. Compressibility of electrospun fiber mats

    E-print Network

    Choong, Looh Tchuin

    Compressive properties of electrospun fiber mats are reported for the first time. Mats of bisphenol-A polysulfone (PSU) and of poly(trimethyl hexamethylene terephthalamide) [PA 6(3)T] were electrospun and annealed over a ...

  8. COMPRESSIVE SINGLEPIXEL IMAGING Technical report

    E-print Network

    Thompson, Andrew

    COMPRESSIVE SINGLEPIXEL IMAGING Technical report Andrew Thompson Technical report Andrew Thompson, University of Edinburgh 20 January 2011 1. INTRODUCTION This report relates to an internship project carried out at SELEX Galileo from August 2010 to January 2011

  9. Electrical conductivity of compressed argon

    SciTech Connect

    Bauer, R.; Windl, W.; Collins, L.; Kress, J.; Kwon, I.

    1997-10-01

    The authors report calculations of the electrical conductivity of solid argon as a function of compression within the density functional local density approximation formulation for a norm-conserving pseudopotential using both electron-phonon coupling and molecular dynamics techniques.

  10. A low cost expander combustor device that takes compressed air, adds thermal energy and then expands the gas to drive an electrical generator is to be designed by modifying an existing internal

    E-print Network

    A low cost expander combustor device that takes compressed air, adds thermal energy combustion spark ignition engine. Compressed air from a storage tank (CT) will be introduced and a little while in compression stage. To save the maximum amount of pump work the compressed air

  11. 46 CFR 194.15-15 - Chemicals other than compressed gases.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Scientific Laboratory § 194.15-15 Chemicals other than compressed gases. Chemicals, including those listed in 49 CFR part 172, may be stored in small working quantities in the chemical laboratory. ... 46 Shipping 7 2010-10-01 2010-10-01 false Chemicals other than compressed gases. 194.15-15...

  12. 46 CFR 194.15-15 - Chemicals other than compressed gases.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Scientific Laboratory § 194.15-15 Chemicals other than compressed gases. Chemicals, including those listed in 49 CFR part 172, may be stored in small working quantities in the chemical laboratory. ... 46 Shipping 7 2013-10-01 2013-10-01 false Chemicals other than compressed gases. 194.15-15...

  13. 46 CFR 194.15-15 - Chemicals other than compressed gases.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Scientific Laboratory § 194.15-15 Chemicals other than compressed gases. Chemicals, including those listed in 49 CFR part 172, may be stored in small working quantities in the chemical laboratory. ... 46 Shipping 7 2011-10-01 2011-10-01 false Chemicals other than compressed gases. 194.15-15...

  14. 46 CFR 194.15-15 - Chemicals other than compressed gases.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Scientific Laboratory § 194.15-15 Chemicals other than compressed gases. Chemicals, including those listed in 49 CFR part 172, may be stored in small working quantities in the chemical laboratory. ... 46 Shipping 7 2014-10-01 2014-10-01 false Chemicals other than compressed gases. 194.15-15...

  15. 46 CFR 194.15-15 - Chemicals other than compressed gases.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Scientific Laboratory § 194.15-15 Chemicals other than compressed gases. Chemicals, including those listed in 49 CFR part 172, may be stored in small working quantities in the chemical laboratory. ... 46 Shipping 7 2012-10-01 2012-10-01 false Chemicals other than compressed gases. 194.15-15...

  16. How to perform chest compressions.

    PubMed

    Parry, Andrew

    2015-11-18

    Rationale and key points This article outlines the correct and effective technique for performing chest compressions for adults in cardiac arrest. Correct performance of chest compressions relies on various factors that are within the control of the nurse. Therefore, it is essential that nurses have comprehensive knowledge of this vital skill. Techniques that deviate from evidence-based recommendations may lead to an ineffective resuscitation attempt and unfavourable outcomes for patients. ? Accurate hand placement on the patient's chest is vital to ensure the heart is compressed effectively. ? Adhering to the recommended depth and rate of compression is fundamental to perfuse the myocardium. ? Interruptions to chest compressions should be kept to a minimum. Reflective activity Clinical skills articles can help update your practice and ensure it remains evidence based. Apply this article to your practice. Reflect on and write a short account of: 1. Your chest compression technique and consider if it follows the evidence base provided in this article. 2. How this article will change your practice. 3. The need to update your cardiopulmonary resuscitation skills. Subscribers can upload their reflective accounts at: rcni.com/portfolio . PMID:26576912

  17. 29 CFR 1917.154 - Compressed air.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 7 2011-07-01 2011-07-01 false Compressed air. 1917.154 Section 1917.154 Labor Regulations...) MARINE TERMINALS Related Terminal Operations and Equipment § 1917.154 Compressed air. Employees shall be... this part during cleaning with compressed air. Compressed air used for cleaning shall not exceed...

  18. 29 CFR 1917.154 - Compressed air.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 7 2012-07-01 2012-07-01 false Compressed air. 1917.154 Section 1917.154 Labor Regulations...) MARINE TERMINALS Related Terminal Operations and Equipment § 1917.154 Compressed air. Employees shall be... this part during cleaning with compressed air. Compressed air used for cleaning shall not exceed...

  19. 29 CFR 1917.154 - Compressed air.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 7 2014-07-01 2014-07-01 false Compressed air. 1917.154 Section 1917.154 Labor Regulations...) MARINE TERMINALS Related Terminal Operations and Equipment § 1917.154 Compressed air. Employees shall be... this part during cleaning with compressed air. Compressed air used for cleaning shall not exceed...

  20. Video Compressive Sensing Using Gaussian Mixture Models

    E-print Network

    Carin, Lawrence

    1 Video Compressive Sensing Using Gaussian Mixture Models Jianbo Yang, Xin Yuan, Xuejun Liao) based algorithm is proposed for video reconstruction from temporally-compressed video measurements reconstructed from simulated compressive video measurements, and from a real compressive video camera. We also

  1. Compressed Sensing Reconstruction via Belief Propagation

    E-print Network

    Compressed Sensing Reconstruction via Belief Propagation Shriram Sarvotham, Dror Baron and Richard, USA July 14, 2006 Abstract Compressed sensing is an emerging field that enables to reconstruct sparse compressible signals in a compressible way? In other words, can we sense only that part of the signal

  2. Compressive Sensing Over Networks Soheil Feizi

    E-print Network

    Médard, Muriel

    Compressive Sensing Over Networks Soheil Feizi MIT Email: sfeizi@mit.edu Muriel M´edard MIT Email some applications of compressive sensing over networks. We make a connection between compressive of compressive sensing and traditional information theoretic approaches is at their decoding side. Although

  3. q-ary Compressive Sensing Youssef Mroueh ,

    E-print Network

    Poggio, Tomaso

    q-ary Compressive Sensing Youssef Mroueh , , Lorenzo Rosasco,§ CBCL, CSAIL, Massachusetts Institute-ary compressive sensing, an extension of 1-bit compressive sensing. We propose a novel sensing mechanism theoretically and empirically. Results in 1-bit compressive sensing are recovered as a special case. Our

  4. Fecal Impaction Causing Pelvic Venous Compression and Edema.

    PubMed

    Naramore, Sara; Aziz, Faisal; Alexander, Chandran Paul; Methratta, Sosamma; Cilley, Robert; Rocourt, Dorothy

    2015-09-28

    Chronic constipation is a common condition which may result in fecal impaction. A 13-year-old male with chronic constipation and encopresis presented with fecal impaction for three weeks. The impaction caused abdominal pain, distension, encopresis, and decreased oral intake. He was found in severe distress with non-pitting edema of his feet and ankles along with perineal edema. The pedal edema worsened after receiving a fluid bolus, so concern arose for venous compression or a thrombus. A Duplex Ultrasound demonstrated changes in the venous waveforms of the bilateral external iliac and common femoral veins without thrombosis. Manual disimpaction and polyethylene glycol 3350 with electrolytes resolved the pedal and perineal edema. Four months later, he had soft bowel movements without recurrence of the edema. A repeat Duplex Ultrasound was normal. We present a child in whom severe fecal impaction caused pelvic venous compression resulting in bilateral pedal and perineal edema. PMID:26500749

  5. Fecal Impaction Causing Pelvic Venous Compression and Edema

    PubMed Central

    Naramore, Sara; Aziz, Faisal; Alexander, Chandran Paul; Methratta, Sosamma; Cilley, Robert; Rocourt, Dorothy

    2015-01-01

    Chronic constipation is a common condition which may result in fecal impaction. A 13-year-old male with chronic constipation and encopresis presented with fecal impaction for three weeks. The impaction caused abdominal pain, distension, encopresis, and decreased oral intake. He was found in severe distress with non-pitting edema of his feet and ankles along with perineal edema. The pedal edema worsened after receiving a fluid bolus, so concern arose for venous compression or a thrombus. A Duplex Ultrasound demonstrated changes in the venous waveforms of the bilateral external iliac and common femoral veins without thrombosis. Manual disimpaction and polyethylene glycol 3350 with electrolytes resolved the pedal and perineal edema. Four months later, he had soft bowel movements without recurrence of the edema. A repeat Duplex Ultrasound was normal. We present a child in whom severe fecal impaction caused pelvic venous compression resulting in bilateral pedal and perineal edema. PMID:26500749

  6. Mechanics of the Compression Wood Response: II. On the Location, Action, and Distribution of Compression Wood Formation.

    PubMed

    Archer, R R; Wilson, B F

    1973-04-01

    A new method for simulation of cross-sectional growth provided detailed information on the location of normal wood and compression wood increments in two tilted white pine (Pinus strobus L.) leaders. These data were combined with data on stiffness, slope, and curvature changes over a 16-week period to make the mechanical analysis. The location of compression wood changed from the under side to a flank side and then to the upper side of the leader as the geotropic stimulus decreased, owing to compression wood action. Its location shifted back to a flank side when the direction of movement of the leader reversed. A model for this action, based on elongation strains, was developed and predicted the observed curvature changes with elongation strains of 0.3 to 0.5%, or a maximal compressive stress of 60 to 300 kilograms per square centimeter. After tilting, new wood formation was distributed so as to maintain consistent strain levels along the leaders in bending under gravitational loads. The computed effective elastic moduli were about the same for the two leaders throughout the season. PMID:16658408

  7. 30 CFR 75.1730 - Compressed air; general; compressed air systems.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Compressed air; general; compressed air systems... Compressed air; general; compressed air systems. (a) All pressure vessels shall be constructed, installed... Safety and Health district office. (b) Compressors and compressed-air receivers shall be equipped...

  8. 30 CFR 75.1730 - Compressed air; general; compressed air systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Compressed air; general; compressed air systems... Compressed air; general; compressed air systems. (a) All pressure vessels shall be constructed, installed... Safety and Health district office. (b) Compressors and compressed-air receivers shall be equipped...

  9. 30 CFR 75.1730 - Compressed air; general; compressed air systems.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Compressed air; general; compressed air systems... Compressed air; general; compressed air systems. (a) All pressure vessels shall be constructed, installed... Safety and Health district office. (b) Compressors and compressed-air receivers shall be equipped...

  10. 30 CFR 75.1730 - Compressed air; general; compressed air systems.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Compressed air; general; compressed air systems... Compressed air; general; compressed air systems. (a) All pressure vessels shall be constructed, installed... Safety and Health district office. (b) Compressors and compressed-air receivers shall be equipped...

  11. 30 CFR 75.1730 - Compressed air; general; compressed air systems.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Compressed air; general; compressed air systems... Compressed air; general; compressed air systems. (a) All pressure vessels shall be constructed, installed... Safety and Health district office. (b) Compressors and compressed-air receivers shall be equipped...

  12. A COMPRESSION METHOD FOR 3-D LASER RANGE SCANS OF INDOOR ENVIRONMENTS BASED ON COMPRESSIVE SENSING

    E-print Network

    Barshan, Billur

    A COMPRESSION METHOD FOR 3-D LASER RANGE SCANS OF INDOOR ENVIRONMENTS BASED ON COMPRESSIVE SENSING efficiently. We propose a novel compression technique based on compressive sensing for 3-D range measurements are then com- pressed based on compressive sensing. The method is similar to difference encoding

  13. Conductivity enhancement of multiwalled carbon nanotube thin film via thermal compression method

    PubMed Central

    2014-01-01

    For the first time, the thermal compression method is applied to effectively enhance the electrical conductivity of carbon nanotube thin films (CNTFs). With the assistance of heat and pressure on the CNTFs, the neighbor multiwalled carbon nanotubes (CNTs) start to link with each other, and then these separated CNTs are twined into a continuous film while the compression force, duration, and temperature are quite enough for the reaction. Under the compression temperature of 400°C and the compression force of 100 N for 50 min, the sheet resistance can be reduced from 17 to 0.9 k ?/sq for the CNTFs with a thickness of 230 nm. Moreover, the effects of compression temperature and the duration of thermal compression on the conductivity of CNTF are also discussed in this work. PMID:25232300

  14. Adult Learners' Week in Australia.

    ERIC Educational Resources Information Center

    Cross, John

    2002-01-01

    Promotional materials and activities for Australia's Adult Learners Week, which are shaped by a variety of stakeholders , include media strategies and a website. Activities are evaluated using a market research company and website and telephone hotline statistics. (SK)

  15. Working with compressed gas Canadian Centre for Occupational

    E-print Network

    Cohen, Robert E.

    for acetylene as fuel gas for cutting and welding #12;What to do when receiving cylinders · Inspect. Ensure or chain or wire rope slings · Transport with specially built hand carts · Transport device should have

  16. Compressive Sensing Based on Candes and Tao's work

    E-print Network

    Vaswani, Namrata

    DCT coefficients are zero (or small enough to be approx. by zero): exploited by JPEG. #12;Idea of CS Uncertainty Principle (UUP) at about level 3S", then the solution, ^x to P1 is unique and is equal to x(e-N )) · Similar results exist for random Fourier and Bernoulli also. #12;Uniform Uncertainty Principle

  17. Compression of fingerprint data using the wavelet vector quantization image compression algorithm. 1992 progress report

    SciTech Connect

    Bradley, J.N.; Brislawn, C.M.

    1992-04-11

    This report describes the development of a Wavelet Vector Quantization (WVQ) image compression algorithm for fingerprint raster files. The pertinent work was performed at Los Alamos National Laboratory for the Federal Bureau of Investigation. This document describes a previously-sent package of C-language source code, referred to as LAFPC, that performs the WVQ fingerprint compression and decompression tasks. The particulars of the WVQ algorithm and the associated design procedure are detailed elsewhere; the purpose of this document is to report the results of the design algorithm for the fingerprint application and to delineate the implementation issues that are incorporated in LAFPC. Special attention is paid to the computation of the wavelet transform, the fast search algorithm used for the VQ encoding, and the entropy coding procedure used in the transmission of the source symbols.

  18. Hybrid Vapor Compression Adsorption System: Thermal Storage Using Hybrid Vapor Compression Adsorption System

    SciTech Connect

    2012-01-04

    HEATS Project: UTRC is developing a new climate-control system for EVs that uses a hybrid vapor compression adsorption system with thermal energy storage. The targeted, closed system will use energy during the battery-charging step to recharge the thermal storage, and it will use minimal power to provide cooling or heating to the cabin during a drive cycle. The team will use a unique approach of absorbing a refrigerant on a metal salt, which will create a lightweight, high-energy-density refrigerant. This unique working pair can operate indefinitely as a traditional vapor compression heat pump using electrical energy, if desired. The project will deliver a hot-and-cold battery that provides comfort to the passengers using minimal power, substantially extending the driving range of EVs.

  19. Three-Dimensional Data Compression with Anisotropic Diffusion

    E-print Network

    sources such as CT or MRI scans. With JPEG 2000 [9] and DICOM [7] for medical imaging, both the 2-D and 3 diffusion on compression quality. Related Work. PDE-based approaches [1, 6, 8] rely on the common idea

  20. Data Compression via Logic Synthesis Luca Amaru1

    E-print Network

    De Micheli, Giovanni

    to reduce the footprint and resource usage of data. In this general context, lossless data compression-traditional EDA fields, e.g., cure of cancer [1], smart water [2], cure of genetic diseases [3], smart grid [4], etc. In this work, we use EDA synthesis techniques to reduce the footprint and resource usage

  1. Expanding Window Compressed Sensing for Non-Uniform Compressible Signals

    PubMed Central

    Liu, Yu; Zhu, Xuqi; Zhang, Lin; Cho, Sung Ho

    2012-01-01

    Many practical compressible signals like image signals or the networked data in wireless sensor networks have non-uniform support distribution in their sparse representation domain. Utilizing this prior information, a novel compressed sensing (CS) scheme with unequal protection capability is proposed in this paper by introducing a windowing strategy called expanding window compressed sensing (EW-CS). According to the importance of different parts of the signal, the signal is divided into several nested subsets, i.e., the expanding windows. Each window generates its own measurements using a random sensing matrix. The more significant elements are contained by more windows, so they are captured by more measurements. This design makes the EW-CS scheme have more convenient implementation and better overall recovery quality for non-uniform compressible signals than ordinary CS schemes. These advantages are theoretically analyzed and experimentally confirmed. Moreover, the EW-CS scheme is applied to the compressed acquisition of image signals and networked data where it also has superior performance than ordinary CS and the existing unequal protection CS schemes. PMID:23201984

  2. 2012 ARPA-E Energy Innovation Summit: Profiling General Compression: A River of Wind

    ScienceCinema

    Marcus, David; Ingersoll, Eric

    2012-03-21

    The third annual ARPA-E Energy Innovation Summit was held in Washington D.C. in February, 2012. The event brought together key players from across the energy ecosystem - researchers, entrepreneurs, investors, corporate executives, and government officials - to share ideas for developing and deploying the next generation of energy technologies. A few videos were selected for showing during the Summit to attendees. These 'performer videos' highlight innovative research that is ongoing and related to the main topics of the Summit's sessions. Featured in this video are David Marcus, Founder of General Compression, and Eric Ingersoll, CEO of General Compression. General Compression, with the help of ARPA-E funding, has created an advanced air compression process which can store and release more than a weeks worth of the energy generated by wind turbines.

  3. 2012 ARPA-E Energy Innovation Summit: Profiling General Compression: A River of Wind

    SciTech Connect

    Marcus, David; Ingersoll, Eric

    2012-02-29

    The third annual ARPA-E Energy Innovation Summit was held in Washington D.C. in February, 2012. The event brought together key players from across the energy ecosystem - researchers, entrepreneurs, investors, corporate executives, and government officials - to share ideas for developing and deploying the next generation of energy technologies. A few videos were selected for showing during the Summit to attendees. These 'performer videos' highlight innovative research that is ongoing and related to the main topics of the Summit's sessions. Featured in this video are David Marcus, Founder of General Compression, and Eric Ingersoll, CEO of General Compression. General Compression, with the help of ARPA-E funding, has created an advanced air compression process which can store and release more than a weeks worth of the energy generated by wind turbines.

  4. Perceptual Image Compression in Telemedicine

    NASA Technical Reports Server (NTRS)

    Watson, Andrew B.; Ahumada, Albert J., Jr.; Eckstein, Miguel; Null, Cynthia H. (Technical Monitor)

    1996-01-01

    The next era of space exploration, especially the "Mission to Planet Earth" will generate immense quantities of image data. For example, the Earth Observing System (EOS) is expected to generate in excess of one terabyte/day. NASA confronts a major technical challenge in managing this great flow of imagery: in collection, pre-processing, transmission to earth, archiving, and distribution to scientists at remote locations. Expected requirements in most of these areas clearly exceed current technology. Part of the solution to this problem lies in efficient image compression techniques. For much of this imagery, the ultimate consumer is the human eye. In this case image compression should be designed to match the visual capacities of the human observer. We have developed three techniques for optimizing image compression for the human viewer. The first consists of a formula, developed jointly with IBM and based on psychophysical measurements, that computes a DCT quantization matrix for any specified combination of viewing distance, display resolution, and display brightness. This DCT quantization matrix is used in most recent standards for digital image compression (JPEG, MPEG, CCITT H.261). The second technique optimizes the DCT quantization matrix for each individual image, based on the contents of the image. This is accomplished by means of a model of visual sensitivity to compression artifacts. The third technique extends the first two techniques to the realm of wavelet compression. Together these two techniques will allow systematic perceptual optimization of image compression in NASA imaging systems. Many of the image management challenges faced by NASA are mirrored in the field of telemedicine. Here too there are severe demands for transmission and archiving of large image databases, and the imagery is ultimately used primarily by human observers, such as radiologists. In this presentation I will describe some of our preliminary explorations of the applications of our technology to the special problems of telemedicine.

  5. The compressive stiffness of human pediatric heads.

    PubMed

    Loyd, Andre Matthew; Nightingale, Roger W; Luck, Jason F; Song, Yin; Fronheiser, Lucy; Cutcliffe, Hattie; Myers, Barry S; Dale Bass, Cameron R

    2015-11-01

    Head injury is a persistent and costly problem for both children and adults. Globally, approximately 10 million people are hospitalized each year for head injuries. Knowing the structural properties of the head is important for modeling the response of the head in impact, and for providing insights into mechanisms of head injury. Hence, the goal of this study was to measure the sub-injurious structural stiffness of whole pediatric heads. 12 cadaveric pediatric (20-week-gestation to 16 years old) heads were tested in a battery of viscoelastic compression tests. The heads were compressed in both the lateral and anterior-posterior directions to 5% of gauge length at normalized deformation rates of 0.0005/s, 0.01/s, 0.1/s, and 0.3/s. Because of the non-linear nature of the response, linear regression models were used to calculate toe region (<2.5%) and elastic region (>2.5%) stiffness separately so that meaningful comparisons could be made across rate, age, and direction. The results showed that age was the dominant factor in predicting the structural stiffness of the human head. A large and statistically significant increase in the stiffness of both the toe region and the elastic region was observed with increasing age (p<0.0001), but no significant difference was seen across direction or normalized deformation rate. The stiffness of the elastic region increased from as low as 5N/mm in the neonate to >4500N/mm in the 16 year old. The changes in stiffness with age may be attributed to the disappearance of soft sutures and the thickening of skull bones with age. PMID:26476760

  6. URe{sub 2}-A compressibility study of allotropic phases

    SciTech Connect

    Shukla, B. Shekar, N. V. Chandra Sahu, P. Ch.

    2014-04-24

    URe{sub 2} compound exists in two phases- orthorhombic and hexagonal. The hexagonal phase has been prepared using arc melting and annealingat 500°C for one week, whereas the orthorhombic phase was achieved by annealing the arc melted sample at a temperature 150°C for the same period. High pressure x-ray diffraction studies on these two allotropic forms of URe{sub 2} have been carried out up to ?15GPa using a diamond anvil cell. Normal compression was observed without any kind of phase transformation; although there is a probability of transformation from the metastable hexagonal to itsstable orthorhombicphase under pressure.

  7. Comparison on accuracy of image matching between lossy JPEG compression and lossy JPEG 2000 compression

    NASA Astrophysics Data System (ADS)

    Matsuoka, Ryuji; Sone, Mitsuo; Sudo, Noboru; Yokotsuka, Hideyo; Shirai, Naoki

    2013-10-01

    This paper reports an experiment conducted in order to compare lossy JPEG compression and lossy JPEG 2000 compression on the accuracy of image matching. The experiment has been conducted by using 54 color images of diverse textures and diverse tones of color on the assumption that image matching utilizes a pair of images reconstructed from image data which are lossily compressed in an ordinary digital camera. Lossy JPEG compression has been executed with a set of compression parameters utilized in a digital camera Canon EOS 20D, while lossy JPEG 2000 compression has been executed in the way as the file size of a piece of JPEG 2000 compressed image data is the same file size of the corresponding JPEG compressed image data. Moreover, we have prepared another set of JPEG and JPEG 2000 compressed image data which are lossily compressed with the compression ratio expected for an ordinary color image when it is compressed in the EOS 20D. When the file size of a piece of JPEG 2000 compressed image data is the same as that of a piece of JPEG compressed image data, the experiment results clearly show that the compression performance of JPEG 2000 compression would be superior to that of JPEG compression on image quality as to pixel value in RGB color space. On the contrary, the results do not necessarily indicate that JPEG 2000 compression would be able to provide more accurate matching results than JPEG compression.

  8. Adaptive Multi-Rate Compression Effects on Vowel Analysis

    PubMed Central

    Ireland, David; Knuepffer, Christina; McBride, Simon J.

    2015-01-01

    Signal processing on digitally sampled vowel sounds for the detection of pathological voices has been firmly established. This work examines compression artifacts on vowel speech samples that have been compressed using the adaptive multi-rate codec at various bit-rates. Whereas previous work has used the sensitivity of machine learning algorithm to test for accuracy, this work examines the changes in the extracted speech features themselves and thus report new findings on the usefulness of a particular feature. We believe this work will have potential impact for future research on remote monitoring as the identification and exclusion of an ill-defined speech feature that has been hitherto used, will ultimately increase the robustness of the system. PMID:26347863

  9. 30 CFR 75.1730 - Compressed air; general; compressed air systems.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...general; compressed air systems. (a) All pressure vessels shall...and compressed-air receivers shall...with automatic pressure-relief valves...Repairs involving the pressure system of compressors...or compressed-air-powered...

  10. 30 CFR 75.1730 - Compressed air; general; compressed air systems.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...general; compressed air systems. (a) All pressure vessels shall...and compressed-air receivers shall...with automatic pressure-relief valves...Repairs involving the pressure system of compressors...or compressed-air-powered...

  11. 30 CFR 75.1730 - Compressed air; general; compressed air systems.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...general; compressed air systems. (a) All pressure vessels shall...and compressed-air receivers shall...with automatic pressure-relief valves...Repairs involving the pressure system of compressors...or compressed-air-powered...

  12. Compression of spectral meteorological imagery

    NASA Technical Reports Server (NTRS)

    Miettinen, Kristo

    1993-01-01

    Data compression is essential to current low-earth-orbit spectral sensors with global coverage, e.g., meteorological sensors. Such sensors routinely produce in excess of 30 Gb of data per orbit (over 4 Mb/s for about 110 min) while typically limited to less than 10 Gb of downlink capacity per orbit (15 minutes at 10 Mb/s). Astro-Space Division develops spaceborne compression systems for compression ratios from as little as three to as much as twenty-to-one for high-fidelity reconstructions. Current hardware production and development at Astro-Space Division focuses on discrete cosine transform (DCT) systems implemented with the GE PFFT chip, a 32x32 2D-DCT engine. Spectral relations in the data are exploited through block mean extraction followed by orthonormal transformation. The transformation produces blocks with spatial correlation that are suitable for further compression with any block-oriented spatial compression system, e.g., Astro-Space Division's Laplacian modeler and analytic encoder of DCT coefficients.

  13. 5 CFR 610.121 - Establishment of work schedules.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Establishment of work schedules. 610.121 Section 610.121 Administrative...REGULATIONS HOURS OF DUTY Weekly and Daily Scheduling of Work Work Schedules § 610.121 Establishment of work...

  14. 5 CFR 610.121 - Establishment of work schedules.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 2013-01-01 false Establishment of work schedules. 610.121 Section 610.121 Administrative...REGULATIONS HOURS OF DUTY Weekly and Daily Scheduling of Work Work Schedules § 610.121 Establishment of work...

  15. 5 CFR 610.121 - Establishment of work schedules.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Establishment of work schedules. 610.121 Section 610.121 Administrative...REGULATIONS HOURS OF DUTY Weekly and Daily Scheduling of Work Work Schedules § 610.121 Establishment of work...

  16. 5 CFR 610.121 - Establishment of work schedules.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 2011-01-01 false Establishment of work schedules. 610.121 Section 610.121 Administrative...REGULATIONS HOURS OF DUTY Weekly and Daily Scheduling of Work Work Schedules § 610.121 Establishment of work...

  17. 5 CFR 610.121 - Establishment of work schedules.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 2010-01-01 false Establishment of work schedules. 610.121 Section 610.121 Administrative...REGULATIONS HOURS OF DUTY Weekly and Daily Scheduling of Work Work Schedules § 610.121 Establishment of work...

  18. A PDF closure model for compressible turbulent chemically reacting flows

    NASA Technical Reports Server (NTRS)

    Kollmann, W.

    1992-01-01

    The objective of the proposed research project was the analysis of single point closures based on probability density function (pdf) and characteristic functions and the development of a prediction method for the joint velocity-scalar pdf in turbulent reacting flows. Turbulent flows of boundary layer type and stagnation point flows with and without chemical reactions were be calculated as principal applications. Pdf methods for compressible reacting flows were developed and tested in comparison with available experimental data. The research work carried in this project was concentrated on the closure of pdf equations for incompressible and compressible turbulent flows with and without chemical reactions.

  19. Simulation of Inviscid Compressible Multi-Phase Flow with Condensation

    NASA Technical Reports Server (NTRS)

    Kelleners, Philip

    2003-01-01

    Condensation of vapours in rapid expansions of compressible gases is investigated. In the case of high temperature gradients the condensation will start at conditions well away from thermodynamic equilibrium of the fluid. In those cases homogeneous condensation is dominant over heterogeneous condensation. The present work is concerned with development of a simulation tool for computation of high speed compressible flows with homogeneous condensation. The resulting ow solver should preferably be accurate and robust to be used for simulation of industrial flows in general geometries.

  20. 78 FR 62305 - Fire Prevention Week, 2013

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-16

    ...Proclamation 9034 of October 4, 2013 Fire Prevention Week, 2013 By the President...of dollars each year. During Fire Prevention Week, we pay tribute to the...through October 12, 2013, as Fire Prevention Week. On Sunday, October...

  1. 75 FR 62307 - Fire Prevention Week, 2010

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-08

    ...Proclamation 8577 of October 1, 2010 Fire Prevention Week, 2010 By the President...America A Proclamation During Fire Prevention Week, we reaffirm the importance...to fire and its consequences. Fire Prevention Week also calls our...

  2. 78 FR 71431 - National Family Week, 2013

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-27

    ...Proclamation 9061--National Family Week, 2013 Presidential Documents Federal Register...9061 of November 22, 2013 National Family Week, 2013 By the President of the United States...American society. During National Family Week, we celebrate the spirit that moves...

  3. 76 FR 71445 - American Education Week, 2011

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-17

    ...Proclamation 8753--American Education Week, 2011 Presidential Documents Federal Register...of November 14, 2011 American Education Week, 2011 By the President of the United States...thriving democracy. During American Education Week, we acknowledge the central role...

  4. 76 FR 43107 - Captive Nations Week, 2011

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-19

    ...Proclamation 8692--Captive Nations Week, 2011 Presidential Documents Federal Register...8692 of July 15, 2011 Captive Nations Week, 2011 By the President of the United States...shaped our world. During Captive Nations Week, we remember the men and women...

  5. 77 FR 22177 - National Volunteer Week, 2012

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-12

    ...Proclamation 8797--National Volunteer Week, 2012 Proclamation 8798--Pan American Day and Pan American Week, 2012 Proclamation 8799--National Former...8797 of April 9, 2012 National Volunteer Week, 2012 By the President of the United...

  6. 78 FR 69749 - American Education Week, 2013

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-20

    ...Proclamation 9058--American Education Week, 2013 Presidential Documents Federal Register...of November 15, 2013 American Education Week, 2013 By the President of the United States...talent to lead. During American Education Week, we reaffirm our commitment to the...

  7. 78 FR 44867 - Captive Nations Week, 2013

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-24

    ...Proclamation 8998--Captive Nations Week, 2013 Presidential Documents Federal Register...8998 of July 19, 2013 Captive Nations Week, 2013 By the President of the United States...only to a privileged few. Captive Nations Week is an opportunity to reaffirm...

  8. 76 FR 63801 - Fire Prevention Week, 2011

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-13

    ...Proclamation 8732--Fire Prevention Week, 2011 Proclamation 8733--National School Lunch Week, 2011 Proclamation 8734--Leif Erikson...Proclamation 8732 of October 7, 2011 Fire Prevention Week, 2011 By the President of the United...

  9. Low-grade elastic compression regimen for venous leg ulcers - an effective compromise for patients requiring daily dressing changes.

    PubMed

    Dabiri, Ganary; Hammerman, Scott; Carson, Polly; Falanga, Vincent

    2015-12-01

    Venous leg ulcers (VLUs) affect millions of patients worldwide and are a tremendous financial burden on our health care system. The hallmark of venous disease of the lower extremities is venous hypertension, and compression is the current mainstay of treatment. However, many patients are non-compliant, partly because of the complexity of the dressings and the difficulties with application and removal. The aim of our study was to test an effective compression dressing regimen for patients with VLUs who require changing the ulcer primary dressing twice daily. We used two layers of a latex-free tubular elastic bandage for compression. The primary endpoint of our study was increased wound-healing rate and our secondary endpoint was complete wound closure. All active study subjects had positive healing rates at week 4 and week 8. Two subjects achieved complete wound closure by week 8. We conclude that compression with a latex-free tubular elastic bandage can be safely used in patients with VLUs requiring frequent dressing changes. This type of compression allows for daily inspection of wounds, dressing changes at home, flexibility in the context of clinical trials, and is a compromise for patients who are intolerant to compression dressings. PMID:24267477

  10. Stem compression reversibly reduces phloem transport in Pinus sylvestris trees.

    PubMed

    Henriksson, Nils; Tarvainen, Lasse; Lim, Hyungwoo; Tor-Ngern, Pantana; Palmroth, Sari; Oren, Ram; Marshall, John; Näsholm, Torgny

    2015-10-01

    Manipulating tree belowground carbon (C) transport enables investigation of the ecological and physiological roles of tree roots and their associated mycorrhizal fungi, as well as a range of other soil organisms and processes. Girdling remains the most reliable method for manipulating this flux and it has been used in numerous studies. However, girdling is destructive and irreversible. Belowground C transport is mediated by phloem tissue, pressurized through the high osmotic potential resulting from its high content of soluble sugars. We speculated that phloem transport may be reversibly blocked through the application of an external pressure on tree stems. Thus, we here introduce a technique based on compression of the phloem, which interrupts belowground flow of assimilates, but allows trees to recover when the external pressure is removed. Metal clamps were wrapped around the stems and tightened to achieve a pressure theoretically sufficient to collapse the phloem tissue, thereby aiming to block transport. The compression's performance was tested in two field experiments: a (13)C canopy labelling study conducted on small Scots pine (Pinus sylvestris L.) trees [2-3?m tall, 3-7?cm diameter at breast height (DBH)] and a larger study involving mature pines (?15?m tall, 15-25?cm DBH) where stem respiration, phloem and root carbohydrate contents, and soil CO2 efflux were measured. The compression's effectiveness was demonstrated by the successful blockage of (13)C transport. Stem compression doubled stem respiration above treatment, reduced soil CO2 efflux by 34% and reduced phloem sucrose content by 50% compared with control trees. Stem respiration and soil CO2 efflux returned to normal within 3 weeks after pressure release, and (13)C labelling revealed recovery of phloem function the following year. Thus, we show that belowground phloem C transport can be reduced by compression, and we also demonstrate that trees recover after treatment, resuming C transport in the phloem. PMID:26377876

  11. ForPeerReview Ice age True Polar wander in a compressible and non

    E-print Network

    ForPeerReview Ice age True Polar wander in a compressible and non hydrostatic Earth Journal Ice age (TPW), have continuously been debated, after the pioneering works of the sixties. We show ice age TPW

  12. Compressive behavior of fine sand.

    SciTech Connect

    Martin, Bradley E.; Kabir, Md. E.; Song, Bo; Chen, Wayne

    2010-04-01

    The compressive mechanical response of fine sand is experimentally investigated. The strain rate, initial density, stress state, and moisture level are systematically varied. A Kolsky bar was modified to obtain uniaxial and triaxial compressive response at high strain rates. A controlled loading pulse allows the specimen to acquire stress equilibrium and constant strain-rates. The results show that the compressive response of the fine sand is not sensitive to strain rate under the loading conditions in this study, but significantly dependent on the moisture content, initial density and lateral confinement. Partially saturated sand is more compliant than dry sand. Similar trends were reported in the quasi-static regime for experiments conducted at comparable specimen conditions. The sand becomes stiffer as initial density and/or confinement pressure increases. The sand particle size become smaller after hydrostatic pressure and further smaller after dynamic axial loading.

  13. Analytical and experimental study on complex compressed air pipe network

    NASA Astrophysics Data System (ADS)

    Gai, Yushou; Cai, Maolin; Shi, Yan

    2015-09-01

    To analyze the working characteristics of complex compressed air networks, numerical methods are widely used which are based on finite element technology or intelligent algorithms. However, the effectiveness of the numerical methods is limited. In this paper, to provide a new method to optimize the design and the air supply strategy of the complex compressed air pipe network, firstly, a novel method to analyze the topology structure of the compressed air flow in the pipe network is initially proposed. A matrix is used to describe the topology structure of the compressed air flow. Moreover, based on the analysis of the pressure loss of the pipe network, the relationship between the pressure and the flow of the compressed air is derived, and a prediction method of pressure fluctuation and air flow in a segment in a complex pipe network is proposed. Finally, to inspect the effectiveness of the method, an experiment with a complex network is designed. The pressure and the flow of airflow in the network are measured and studied. The results of the study show that, the predicted results with the proposed method have a good consistency with the experimental results, and that verifies the air flow prediction method of the complex pipe network. This research proposes a new method to analyze the compressed air network and a prediction method of pressure fluctuation and air flow in a segment, which can predicate the fluctuation of the pressure according to the flow of compressed air, and predicate the fluctuation of the flow according to the pressure in a segment of a complex pipe network.

  14. Thermoacoustic compression based on alternating to direct gas flow conversion

    NASA Astrophysics Data System (ADS)

    Sun, D. M.; Wang, K.; Xu, Y.; Shen, Q.; Zhang, X. J.; Qiu, L. M.

    2012-05-01

    We present a remarkable thermoacoustically driven compression effect based on the conversion of gas flow from an alternating state to a direct state. The alternating gas flow is generated by the thermoacoustic effect in thermoacoustic engines, whereas direct gas flow is achieved by means of the flow rectification effect of check valves. A demonstrative thermoacoustic compressor consisting of two standing-wave thermoacoustic engines, two reservoirs, and three check valves is constructed for experimental investigation. With nitrogen as a working gas and an initial pressure of 2.4 MPa in all components, a usable pressure difference of 0.4 MPa is achieved, with the average gas pumping rate reaching 2.85 Nm3/h during the first 3 s of the compression process. The simple mechanical structure and thermally driven nature of the compressor show potential in gas compression, power generation, and refrigeration applications.

  15. A Compressed Air Reduction Program 

    E-print Network

    Hawks, K. D.

    1986-01-01

    stream_source_info ESL-IE-86-06-95.pdf.txt stream_content_type text/plain stream_size 10225 Content-Encoding ISO-8859-1 stream_name ESL-IE-86-06-95.pdf.txt Content-Type text/plain; charset=ISO-8859-1 A COMPRESSED AIR...> the mos t bene fie i a1. The> data displayed a wide variance of compressed air consumption rates which can be attributed to packing problems, since all other usage points are minimal and constant. The readings taken dlJring the "press running" mode...

  16. Simulating Ramp Compression of Diamond

    NASA Astrophysics Data System (ADS)

    Godwal, B. K.; Gonzàlez-Cataldo, F. J.; Jeanloz, R.

    2014-12-01

    We model ramp compression, shock-free dynamic loading, intended to generate a well-defined equation of state that achieves higher densities and lower temperatures than the corresponding shock Hugoniot. Ramp loading ideally approaches isentropic compression for a fluid sample, so is useful for simulating the states deep inside convecting planets. Our model explicitly evaluates the deviation of ramp from "quasi-isentropic" compression. Motivated by recent ramp-compression experiments to 5 TPa (50 Mbar), we calculate the room-temperature isotherm of diamond using first-principles density functional theory and molecular dynamics, from which we derive a principal isentrope and Hugoniot by way of the Mie-Grüneisen formulation and the Hugoniot conservation relations. We simulate ramp compression by imposing a uniaxial strain that then relaxes to an isotropic state, evaluating the change in internal energy and stress components as the sample relaxes toward isotropic strain at constant volume; temperature is well defined for the resulting hydrostatic state. Finally, we evaluate multiple shock- and ramp-loading steps to compare with single-step loading to a given final compression. Temperatures calculated for single-step ramp compression are less than Hugoniot temperatures only above 500 GPa, the two being close to each other at lower pressures. We obtain temperatures of 5095 K and 6815 K for single-step ramp loading to 600 and 800 GPa, for example, which compares well with values of ~5100 K and ~6300 K estimated from previous experiments [PRL,102, 075503, 2009]. At 800 GPa, diamond is calculated to have a temperature of 500 K along the isentrope; 900 K under multi-shock compression (asymptotic result after 8-10 steps); and 3400 K under 3-step ramp loading (200-400-800 GPa). Asymptotic multi-step shock and ramp loading are indistinguishable from the isentrope, within present uncertainties. Our simulations quantify the manner in which current experiments can simulate the deep interiors of planetary bodies, including super-giant extra-Solar planets.

  17. Data compression for satellite images

    NASA Technical Reports Server (NTRS)

    Chen, P. H.; Wintz, P. A.

    1976-01-01

    An efficient data compression system is presented for satellite pictures and two grey level pictures derived from satellite pictures. The compression techniques take advantages of the correlation between adjacent picture elements. Several source coding methods are investigated. Double delta coding is presented and shown to be the most efficient. Both predictive differential quantizing technique and double delta coding can be significantly improved by applying a background skipping technique. An extension code is constructed. This code requires very little storage space and operates efficiently. Simulation results are presented for various coding schemes and source codes.

  18. Data compression in digitized lines

    NASA Technical Reports Server (NTRS)

    Thapa, Khagendra

    1990-01-01

    The problem of data compression is very important in digital photogrammetry, computer assisted cartography, and GIS/LIS. In addition, it is also applicable in many other fields such as computer vision, image processing, pattern recognition, and artificial intelligence. Consequently, there are many algorithms available to solve this problem but none of them are considered to be satisfactory. In this paper, a new method of finding critical points in a digitized curve is explained. This technique, based on the normalized symmetric scattered matrix, is good for both critical points detection and data compression. In addition, the critical points detected by this algorithm are compared with those by zero-crossings.

  19. Compressive sensing based video object compression schemes for surveillance systems

    NASA Astrophysics Data System (ADS)

    Narayanan, Sathiya; Makur, Anamitra

    2015-03-01

    In some surveillance videos, successive frames exhibit correlation in the sense that only a small portion changes (object motion). If the foreground moving objects are segmented from the background they can be coded independently requiring far fewer bits compared to frame-based coding. Huang et al proposed a Compressive Sensing (CS) based Video Object Error Coding (CS-VOEC) where the objects are segmented and coded via motion estimation and compensation. Since motion estimation might be computationally intensive, encoder can be kept simple by performing motion estimation the decoder rather than at the encoder. We propose a novel CS based Video Object Compression (CS-VOC) technique having a simple encoder in which the sensing mechanism is applied directly on the segmented moving objects using a CS matrix. At the decoder, the object motion is first estimated so that a CS reconstruction algorithm can efficiently recover the sparse motion-compensated video object error. In addition to simple encoding, simulation results show our coding scheme performs on par with the state-of-the-art CS based video object error coding scheme. If the object segmentation requires more computations, we propose to deploy a distributed CS framework called Distributed Compressive Video Sensing based Video Object Compression (DCVS-VOC) wherein the object segmentation is done only for key frames.

  20. The Compressibility Burble and the Effect of Compressibility on Pressures and Forces Acting on a Airfoil

    NASA Technical Reports Server (NTRS)

    Stack, John; Lindsey, W F; Littell, Robert E

    1939-01-01

    Simultaneous air-flow photographs and pressure-distribution measurements were made of the NACA 4412 airfoil at high speeds to determine the physical nature of the compressibility burble. The tests were conducted in the NACA 24-inch high-speed wind tunnel. The flow photographs were obtained by the Schlieren method and the pressures were simultaneously measured for 54 stations in the 5-inch-chord airfoil by means of a multiple-tube manometer. Following the general program, a few measurements of total-pressure loss in the wake of the airfoil at high speeds were made to illustrate the magnitude of the losses involved and the extent of the disturbed region; and, finally, in order to relate this work to earlier force-test data, a force test of a 5-inch-chord NACA 4412 airfoil was made. The results show the general nature of the phenomenon known as the compressibility burble. The source of the increased drag is shown to be a compression shock that occurs on the airfoil as its speed approaches the speed of sound. Finally, it is indicated that considerable experimentation is needed in order to understand the phenomenon completely.

  1. Compressive viscoelasticity of freshly excised mouse skin is dependent on specimen thickness, strain level and rate.

    PubMed

    Wang, Yuxiang; Marshall, Kara L; Baba, Yoshichika; Lumpkin, Ellen A; Gerling, Gregory J

    2015-01-01

    Although the skin's mechanical properties are well characterized in tension, little work has been done in compression. Here, the viscoelastic properties of a population of mouse skin specimens (139 samples from 36 mice, aged 5 to 34 weeks) were characterized upon varying specimen thickness, as well as strain level and rate. Over the population, we observed the skin's viscoelasticity to be quite variable, yet found systematic correlation of residual stress ratio with skin thickness and strain, and of relaxation time constants with strain rates. In particular, as specimen thickness ranged from 211 to 671 ?m, we observed significant variation in both quasi-linear viscoelasticity (QLV) parameters, the relaxation time constant (?1 = 0.19 ± 0.10 s) and steady-state residual stress ratio (G? = 0.28 ± 0.13). Moreover, when ?1 was decoupled and fixed, we observed that G? positively correlated with skin thickness. Second, as steady-state stretch was increased (?? from 0.22 to 0.81), we observed significant variation in both QLV parameters (?1 = 0.26 ± 0.14 s, G? = 0.47 ± 0.17), and when ?1 was fixed, G? positively correlated with stretch level. Third, as strain rate was increased from 0.06 to 22.88 s-1, the median time constant ?1 varied from 1.90 to 0.31 s, and thereby negatively correlated with strain rate. These findings indicate that the natural range of specimen thickness, as well as experimental controls of compression level and rate, significantly influence measurements of skin viscoelasticity. PMID:25803703

  2. Compressive Viscoelasticity of Freshly Excised Mouse Skin Is Dependent on Specimen Thickness, Strain Level and Rate

    PubMed Central

    Wang, Yuxiang; Marshall, Kara L.; Baba, Yoshichika; Lumpkin, Ellen A.; Gerling, Gregory J.

    2015-01-01

    Although the skin’s mechanical properties are well characterized in tension, little work has been done in compression. Here, the viscoelastic properties of a population of mouse skin specimens (139 samples from 36 mice, aged 5 to 34 weeks) were characterized upon varying specimen thickness, as well as strain level and rate. Over the population, we observed the skin’s viscoelasticity to be quite variable, yet found systematic correlation of residual stress ratio with skin thickness and strain, and of relaxation time constants with strain rates. In particular, as specimen thickness ranged from 211 to 671 ?m, we observed significant variation in both quasi-linear viscoelasticity (QLV) parameters, the relaxation time constant (?1 = 0.19 ± 0.10 s) and steady-state residual stress ratio (G? = 0.28 ± 0.13). Moreover, when ?1 was decoupled and fixed, we observed that G? positively correlated with skin thickness. Second, as steady-state stretch was increased (?? from 0.22 to 0.81), we observed significant variation in both QLV parameters (?1 = 0.26 ± 0.14 s, G? = 0.47 ± 0.17), and when ?1 was fixed, G? positively correlated with stretch level. Third, as strain rate was increased from 0.06 to 22.88 s?1, the median time constant ?1 varied from 1.90 to 0.31 s, and thereby negatively correlated with strain rate. These findings indicate that the natural range of specimen thickness, as well as experimental controls of compression level and rate, significantly influence measurements of skin viscoelasticity. PMID:25803703

  3. Near-wall modelling of compressible turbulent flows

    NASA Technical Reports Server (NTRS)

    So, Ronald M. C.

    1990-01-01

    Work was carried out to extend the near-wall models formulated for the incompressible Reynolds stress equations to compressible flows. The idea of splitting the compressible dissipation function into a solenoidal part that is not sensitive to changes of compressibility indicators and a compressible part that is directly affected by these changes is adopted. This means that all models involving the dissipation rate could be expressed in terms of the solenoidal dissipation rate and an equation governing its transport could be formulated to close the set of compressible Reynolds stress equations. The near-wall modelling of the dissipation rate equation is investigated and its behavior near a wall is studied in detail using k-epsilon closure. It is found that all existing modelled equations give the wrong behavior for the dissipation rate near a wall. Improvements are suggested and the resultant behavior is found to be in good agreement with near-wall data. Furthermore, the present modified k-epsilon closure is used too calculate a flat plate boundary layer and the results are compared with four existing k-epsilon closures. These comparisons show that all closures tested give essentially the same flow properties, except in a region very close to the wall. In this region, the present k-epsilon closure calculations are in better agreement with measurements and direct simulation data; in particular, the behavior of the dissipation rate.

  4. Near-wall modelling of compressible turbulent flows

    NASA Technical Reports Server (NTRS)

    So, Ronald M. C.

    1990-01-01

    Work was carried out to formulate near-wall models for the equations governing the transport of the temperature-variance and its dissipation rate. With these equations properly modeled, a foundation is laid for their extension together with the heat-flux equations to compressible flows. This extension is carried out in a manner similar to that used to extend the incompressible near-wall Reynolds-stress models to compressible flows. The methodology used to accomplish the extension of the near-wall Reynolds-stress models is examined and the actual extension of the models for the Reynolds-stress equations and the near-wall dissipation-rate equation to compressible flows is given. Then the formulation of the near-wall models for the equations governing the transport of the temperature variance and its dissipation rate is discussed. Finally, a sample calculation of a flat plate compressible turbulent boundary-layer flow with adiabatic wall boundary condition and a free-stream Mach number of 2.5 using a two-equation near-wall closure is presented. The results show that the near-wall two-equation closure formulated for compressible flows is quite valid and the calculated properties are in good agreement with measurements. Furthermore, the near-wall behavior of the turbulence statistics and structure parameters is consistent with that found in incompressible flows.

  5. Isentropic Compression of Multicomponent Mixtures of Fuels and Inert Gases

    NASA Technical Reports Server (NTRS)

    Barragan, Michelle; Julien, Howard L.; Woods, Stephen S.; Wilson, D. Bruce; Saulsberry, Regor L.

    2000-01-01

    In selected aerospace applications of the fuels hydrazine and monomethythydrazine, there occur conditions which can result in the isentropic compression of a multicomponent mixture of fuel and inert gas. One such example is when a driver gas such as helium comes out of solution and mixes with the fuel vapor, which is being compressed. A second example is when product gas from an energetic device mixes with the fuel vapor which is being compressed. Thermodynamic analysis has shown that under isentropic compression, the fuels hydrazine and monomethylhydrazine must be treated as real fluids using appropriate equations of state. The appropriate equations of state are the Peng-Robinson equation of state for hydrazine and the Redlich-Kwong-Soave equation of state for monomethylhydrazine. The addition of an inert gas of variable quantity and input temperature and pressure to the fuel compounds the problem for safety design or analysis. This work provides the appropriate thermodynamic analysis of isentropic compression of the two examples cited. In addition to an entropy balance describing the change of state, an enthalpy balance is required. The presence of multicomponents in the system requires that appropriate mixing rules are identified and applied to the analysis. This analysis is not currently available.

  6. Compressible Turbulent Channel Flows: DNS Results and Modeling

    NASA Technical Reports Server (NTRS)

    Huang, P. G.; Coleman, G. N.; Bradshaw, P.; Rai, Man Mohan (Technical Monitor)

    1994-01-01

    The present paper addresses some topical issues in modeling compressible turbulent shear flows. The work is based on direct numerical simulation of two supersonic fully developed channel flows between very cold isothermal walls. Detailed decomposition and analysis of terms appearing in the momentum and energy equations are presented. The simulation results are used to provide insights into differences between conventional time-and Favre-averaging of the mean-flow and turbulent quantities. Study of the turbulence energy budget for the two cases shows that the compressibility effects due to turbulent density and pressure fluctuations are insignificant. In particular, the dilatational dissipation and the mean product of the pressure and dilatation fluctuations are very small, contrary to the results of simulations for sheared homogeneous compressible turbulence and to recent proposals for models for general compressible turbulent flows. This provides a possible explanation of why the Van Driest density-weighted transformation is so successful in correlating compressible boundary layer data. Finally, it is found that the DNS data do not support the strong Reynolds analogy. A more general representation of the analogy is analysed and shown to match the DNS data very well.

  7. Tensile and compressive behavior of Ti-based bulk metallic glass composites

    NASA Astrophysics Data System (ADS)

    Wang, Yong-sheng; Hao, Guo-jian; Lin, Jun-pin

    2013-06-01

    This article focuses on the tensile and compressive characteristics of a Ti-based bulk metallic glass composite (BMGC). It is found that the yield stress, maximum strength, and fracture strain are 1380 MPa, 1516 MPa, and 4.3% for uniaxial tension, but 1580 MPa, 4010 MPa, and 29% for uniaxial compression, respectively. The composite displays a linear "work hardening" capacity under compression; however, the "work softening" behavior is observed in the true engineering stress-strain curve upon tensile loading. The fracture surfaces of specimens also exhibit dissimilar properties under the different loadings.

  8. Relations of Work Identity, Family Identity, Situational Demands, and Sex with Employee Work Hours

    ERIC Educational Resources Information Center

    Greenhaus, Jeffrey H.; Peng, Ann C.; Allen, Tammy D.

    2012-01-01

    This study examined relations of multiple indicators of work identity and family identity with the number of weekly hours worked by 193 married business professionals. We found that men generally worked long hours regardless of the situational demands to work long hours and the strength of their work and family identities. Women's work hours, on…

  9. TEMPORARY WORK AND DEPRESSIVE SYMPTOMS: A PROPENSITY SCORE ANALYSIS

    PubMed Central

    Quesnel-Vallée, Amélie; DeHaney, Suzanne; Ciampi, Antonio

    2013-01-01

    Recent decades have seen a tremendous increase in the complexity of work arrangements, through job sharing, flexible hours, career breaks, compressed work weeks, shift work, reduced job security, and part-time, contract and temporary work. In this study, we focus on one specific group of workers that arguably most embodies nonstandard employment, namely temporary workers, and examine the consequences of this type of employment on depressive symptoms. This study aims to estimate the effect of being a temporary worker on depressive symptom severity. Accounting for the possibility of mental health selection into temporary work through propensity score analysis, we isolate the direct effects of temporary work on depressive symptoms with varying lags of time since exposure. We use prospective data from the U.S. National Longitudinal Survey of Youth 1979 (NLSY79), which has followed, longitudinally, from 1979 to the present, a nationally representative cohort of American men and women between 14 and 22 years of age in 1979. Three propensity score models were estimated, to capture the effect of different time lags (immediately following exposure, and 2 and 4 years post exposure) between the period of exposure to the outcome. The only significant effects were found among those who had been exposed to temporary work in the two years preceding the outcome measurement. These workers report 1.803 (95% CI 0.552; 3.055) additional depressive symptoms from having experienced this work status (than if they had not been exposed). Moreover, this difference is both statistically and substantively significant, as it represents a 50% increase from the average level of depressive symptoms in this population. PMID:20371142

  10. ACCOUNT NUMBER ERN HOURS 10THS ~ WORK-STUDY

    E-print Network

    MacDonald, Lee

    ACCOUNT NUMBER ERN HOURS 10THS !! !! !! !! ~ WORK-STUDY ~ HOURLY CSU STUDENT ~ HOURLY NONST WEEK 2ND WEEK DATE TIME WORKED ACCOUNT DATE TIME WORKED ACCOUNT MO DAY START STOP HOURS MIN MO DAY on this sheet must be filled I certify that this sheet accurately records the hours worked by the above employee

  11. Self-calibration and biconvex compressive sensing

    NASA Astrophysics Data System (ADS)

    Ling, Shuyang; Strohmer, Thomas

    2015-11-01

    The design of high-precision sensing devises becomes ever more difficult and expensive. At the same time, the need for precise calibration of these devices (ranging from tiny sensors to space telescopes) manifests itself as a major roadblock in many scientific and technological endeavors. To achieve optimal performance of advanced high-performance sensors one must carefully calibrate them, which is often difficult or even impossible to do in practice. In this work we bring together three seemingly unrelated concepts, namely self-calibration, compressive sensing, and biconvex optimization. The idea behind self-calibration is to equip a hardware device with a smart algorithm that can compensate automatically for the lack of calibration. We show how several self-calibration problems can be treated efficiently within the framework of biconvex compressive sensing via a new method called SparseLift. More specifically, we consider a linear system of equations {\\boldsymbol{y}}={\\boldsymbol{D}}{\\boldsymbol{A}}{\\boldsymbol{x}}, where both {\\boldsymbol{x}} and the diagonal matrix {\\boldsymbol{D}} (which models the calibration error) are unknown. By ‘lifting’ this biconvex inverse problem we arrive at a convex optimization problem. By exploiting sparsity in the signal model, we derive explicit theoretical guarantees under which both {\\boldsymbol{x}} and {\\boldsymbol{D}} can be recovered exactly, robustly, and numerically efficiently via linear programming. Applications in array calibration and wireless communications are discussed and numerical simulations are presented, confirming and complementing our theoretical analysis.

  12. Frequency extrapolation by nonconvex compressive sensing

    SciTech Connect

    Chartrand, Rick; Sidky, Emil Y; Pan, Xiaochaun

    2010-12-03

    Tomographic imaging modalities sample subjects with a discrete, finite set of measurements, while the underlying object function is continuous. Because of this, inversion of the imaging model, even under ideal conditions, necessarily entails approximation. The error incurred by this approximation can be important when there is rapid variation in the object function or when the objects of interest are small. In this work, we investigate this issue with the Fourier transform (FT), which can be taken as the imaging model for magnetic resonance imaging (MRl) or some forms of wave imaging. Compressive sensing has been successful for inverting this data model when only a sparse set of samples are available. We apply the compressive sensing principle to a somewhat related problem of frequency extrapolation, where the object function is represented by a super-resolution grid with many more pixels than FT measurements. The image on the super-resolution grid is obtained through nonconvex minimization. The method fully utilizes the available FT samples, while controlling aliasing and ringing. The algorithm is demonstrated with continuous FT samples of the Shepp-Logan phantom with additional small, high-contrast objects.

  13. Arithmetic Coding for Data Compression

    E-print Network

    Howard, Paul G.; Vitter, Jeffrey Scott

    1994-01-01

    . The reduced-precision arithmetic has a provably negligible e ect on the amount of compression achieved. We can speed up the implemen- tation further by use of parallel processing. We discuss the role of probability models and how they provide probability...

  14. Compressive passive millimeter wave imager

    DOEpatents

    Gopalsami, Nachappa; Liao, Shaolin; Elmer, Thomas W; Koehl, Eugene R; Heifetz, Alexander; Raptis, Apostolos C

    2015-01-27

    A compressive scanning approach for millimeter wave imaging and sensing. A Hadamard mask is positioned to receive millimeter waves from an object to be imaged. A subset of the full set of Hadamard acquisitions is sampled. The subset is used to reconstruct an image representing the object.

  15. Fast Progressive Lossless Image Compression

    E-print Network

    Howard, Paul G.; Vitter, Jeffrey Scott

    1994-02-01

    modeling and coding based on that of FELICS In addition we introduce a new pre x code with some advantages over the previously used Golomb and Rice codes Our new progressive method gives compression ratios and speeds similar to those of non progressive...

  16. Culture: Copying, Compression, and Conventionality

    ERIC Educational Resources Information Center

    Tamariz, Mónica; Kirby, Simon

    2015-01-01

    Through cultural transmission, repeated learning by new individuals transforms cultural information, which tends to become increasingly compressible (Kirby, Cornish, & Smith, 2008; Smith, Tamariz, & Kirby, 2013). Existing diffusion chain studies include in their design two processes that could be responsible for this tendency: learning…

  17. COMPRESSIBLE FLOW, ENTRAINMENT, AND MEGAPLUME

    EPA Science Inventory

    It is generally believed that low Mach number, i.e., low-velocity, flow may be assumed to be incompressible flow. Under steady-state conditions, an exact equation of continuity may then be used to show that such flow is non-divergent. However, a rigorous, compressible fluid-dynam...

  18. Compression testing of flammable liquids

    NASA Technical Reports Server (NTRS)

    Briles, O. M.; Hollenbaugh, R. P.

    1979-01-01

    Small cylindrical test chamber determines catalytic effect of given container material on fuel that might contribute to accidental deflagration or detonation below expected temperature under adiabatic compression. Device is useful to producers and users of flammable liquids and to safety specialists.

  19. A programmable image compression system

    NASA Technical Reports Server (NTRS)

    Farrelle, Paul M.

    1989-01-01

    A programmable image compression system which has the necessary flexibility to address diverse imaging needs is described. It can compress and expand single frame video images (monochrome or color) as well as documents and graphics (black and white or color) for archival or transmission applications. Through software control, the compression mode can be set for lossless or controlled quality coding; the image size and bit depth can be varied; and the image source and destination devices can be readily changed. Despite the large combination of image data types, image sources, and algorithms, the system provides a simple consistent interface to the programmer. This system (OPTIPAC) is based on the TITMS320C25 digital signal processing (DSP) chip and has been implemented as a co-processor board for an IBM PC-AT compatible computer. The underlying philosophy can readily be applied to different hardware platforms. By using multiple DSP chips or incorporating algorithm specific chips, the compression and expansion times can be significantly reduced to meet performance requirements.

  20. Safety data sheet Oxygen, compressed.

    E-print Network

    Wikswo, John

    Safety data sheet Oxygen, compressed. Creation date : 27.01.2005 Version : 1.3 GB / E SDS No.3. Details of the supplier of the safety data sheet Company identification BOC, Priestley Road, Worsley376 In case of fire: Stop leak if safe to do so. Precautionary Statement Storage P403 Store in a well

  1. Image deconvolution, denoising and compression

    E-print Network

    Masci, Frank

    Image deconvolution, denoising and compression T.E. Gureyev and Ya.I.Nesterets 15.11.2002 #12 OF CONVOLUTION * = 3% Poisson noise 10% Poisson noise #12;DECONVOLUTION PROBLEM (*)),(),)((),( yxNyxPIyxD +!= Deconvolution problem: given D, P and N, find I (i.e. compensate for noise and the PSF of the imaging system

  2. Device Assists Cardiac Chest Compression

    NASA Technical Reports Server (NTRS)

    Eichstadt, Frank T.

    1995-01-01

    Portable device facilitates effective and prolonged cardiac resuscitation by chest compression. Developed originally for use in absence of gravitation, also useful in terrestrial environments and situations (confined spaces, water rescue, medical transport) not conducive to standard manual cardiopulmonary resuscitation (CPR) techniques.

  3. Teaching Time-Space Compression

    ERIC Educational Resources Information Center

    Warf, Barney

    2011-01-01

    Time-space compression shows students that geographies are plastic, mutable and forever changing. This paper justifies the need to teach this topic, which is rarely found in undergraduate course syllabi. It addresses the impacts of transportation and communications technologies to explicate its dynamics. In summarizing various conceptual…

  4. Stream programming for image and video compression

    E-print Network

    Drake, Matthew Henry

    2006-01-01

    Video playback devices rely on compression algorithms to minimize storage, transmission bandwidth, and overall cost. Compression techniques have high realtime and sustained throughput requirements, and the end of CPU clock ...

  5. Turbulence Modeling for Compressible Shear Flows 

    E-print Network

    Gomez Elizondo, Carlos Arturo 1981-

    2012-11-15

    , state, and momentum equations. Closure models that attempt to address compressibility effects must begin their development from sound first-principles related to the changing nature of pressure as a flow goes from incompressible to compressible regime...

  6. Neural networks for fast image compression 

    E-print Network

    Li, Mu

    1998-01-01

    The image compression system aims at reducing the graphics. number of bits transmitted as well as keeping the fidelity of the image, such that at the receiver, the reconstructed image will have little distortion. The design of an image compression...

  7. Photon level chemical classification using digital compressive ...

    E-print Network

    David S. Wilcox

    2012-11-09

    Oct 12, 2012 ... this digital compressive detection strategy is Poisson photon noise limited and ... form previous full spectral and compressive chemical classification methods, ..... hence the image of the diode laser focal spot size, which spans.

  8. COMPRESSION, ESTIMATION, AND ANALYSIS OF ULTRASONIC SIGNALS

    E-print Network

    Saniie, Jafar

    COMPRESSION, ESTIMATION, AND ANALYSIS OF ULTRASONIC SIGNALS BY GUILHERME CARDOSO DE CARDOSO .................................................................. 5 2.2 Ultrasonic Imaging ................................................................ 7 2. THRESHOLDING TECHNIQUES FOR DENOISING AND COMPRESSING ULTRASONIC SIGNALS ........................... 19 3

  9. Discrete Wigner Function Reconstruction and Compressed Sensing

    E-print Network

    Jia-Ning Zhang; Lei Fang; Mo-Lin Ge

    2011-09-03

    A new reconstruction method for Wigner function is reported for quantum tomography based on compressed sensing. By analogy with computed tomography, Wigner functions for some quantum states can be reconstructed with less measurements utilizing this compressed sensing based method.

  10. ENERGY RECOVERY COUNCIL WEEKLY UPDATE

    E-print Network

    Columbia University

    ." The Allentown (PA) City Council effectively washed its hands this week of a proposed clean air bill championed such proposed monitoring under the Pennsylvania Air Pollution Control Act. D-Waste announced the launch enough energy to power the plant and more than 64,000 homes ­ and serves about two dozen municipalities

  11. Portuguese Special Course: 12 Weeks.

    ERIC Educational Resources Information Center

    Defense Language Inst., Washington, DC.

    This 12-week course in beginning Portuguese comprises four volumes of student text (Lessons 1-55) and a fifth volume of Portuguese-English/English-Portuguese vocabulary. Lesson materials consist of basic dialogs with English translation, recombination dialogs, readings and comprehension questions, oral exercises, and in later units, additional…

  12. Six Week Slavery Novel Unit.

    ERIC Educational Resources Information Center

    Jones, Darolyn Lyn

    Developed in conjunction with a graduate course and used in classrooms with all types of learners, this paper presents a 6-week unit of study on slavery based on two adolescent novels--"NIGHTJOHN" by Gary Paulson and "My Name Is not Angelica" by Scott O'Dell. After a brief introduction to the unit, the paper presents the 14 activities of the unit:…

  13. Compression of multispectral image using HEVC

    NASA Astrophysics Data System (ADS)

    Gao, Feiyu; Ji, Xiangyang; Yan, Chenggang; Dai, Qionghai

    2014-10-01

    Predictive Lossy Compression has been found to be an interesting alternative to conventional transform coding techniques in multispectral image compression. Recently, High Efficiency Video Coding (HEVC) standard has shown significant improvement over state of the art transformation based still-image coding standard. In this paper we study the properties of multispectral image and propose a predictive lossy compression scheme based on HEVC. Empirical analysis shows that our proposed method is superior to the existing state of the art predictive lossy compression schemes.

  14. Radiological Follow-up of New Compression Fractures Following Percutaneous Vertebroplasty

    SciTech Connect

    Tanigawa, Noboru Komemushi, Atsushi; Kariya, Shuji; Kojima, Hiroyuki; Shomura, Yuzo; Sawada, Satoshi

    2006-02-15

    The purpose of the present study was to ascertain chronological changes in the analgesic effects of percutaneous vertebroplasty (PVP) on osteoporotic vertebral compression factures and to radiologically follow new compression fractures after PVP. Seventy-six patients (206 vertebral bodies) were followed radiologically for a mean of 11.5 months. A visual analog scale (VAS; 0-10) was used to assess pain severity, and frontal and lateral plain radiographs of the thoracic and lumbar vertebrae were taken 1-3 days and 1, 4, 10, and 22 months after PVP.The average VAS score was 7.2 {+-} 2.0 (mean pain score {+-} standard deviation) before PVP, 2.5 {+-} 2.3 at 1-3 days after PVP, 2.2 {+-} 2.3 at 1 month, 1.9 {+-} 2.2 at 4 months, 1.8 {+-} 2.4 at 10 months, and 1.0 {+-} 0.2 at 22 months. A new compression fracture was confirmed in 56 vertebral bodies in 28 patients (36.8%), affecting 38 adjacent vertebral bodies (67.8%), 17 nonadjacent vertebral bodies (30.4%), and 1 treated vertebral body (1.8%). A new compression fracture occurred within 1 week of PVP in 2 vertebral bodies (3.6%), between 1 week and 1 month after PVP in 22 (39.3%), between 1 and 3 months in 12 (21.4%), between 3 and 6 months in 12 (21.4%), and after more than 6 months in 8 (14.3%). PVP was highly effective in relieving the pain associated with osteoporosis-induced vertebral compression fractures, and this analgesia was long lasting. Radiological follow-up observation revealed new compression fractures in about one-third of patients. More than half of these new compression fractures occurred in adjacent vertebral bodies within 3 months of PVP.

  15. 77 FR 31143 - Emergency Medical Services Week, 2012

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-24

    ...Proclamation 8824--Emergency Medical Services Week, 2012 Proclamation 8825--National Safe Boating Week, 2012 Proclamation 8826--National Small Business Week, 2012 Proclamation 8827--World Trade Week, 2012...

  16. An Evaluation of a Two Week Teaching Trial Using Interactive Video Technology: Perceptions of Students and Staff.

    ERIC Educational Resources Information Center

    Baker, R. A.; Hansford, B. C.

    This report is concerned with an evaluation of a 2-week teaching trial in 1989 that utilized compressed data--interactive video technology. The trial was a collaborative venture of the University of New England (UNE), TELECOM, the Department of Education, Employment and Training (DEET), and SONY. In general, the University of New England supplied…

  17. 76 FR 4338 - Research and Development Strategies for Compressed & Cryo-Compressed Hydrogen Storage Workshops

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-25

    ... and Development Strategies for Compressed & Cryo- Compressed Hydrogen Storage Workshops AGENCY: Fuel... Laboratory, in conjunction with the Hydrogen Storage team of the EERE Fuel Cell Technologies Program, will be hosting two days of workshops on compressed and cryo-compressed hydrogen storage in the Washington,...

  18. Sparse Bayesian Learning in Compressive Traditional Compressive Sensing (CS) recovery techniques resorts a

    E-print Network

    Freitas, Nando de

    Sparse Bayesian Learning in Compressive Sensing Abstract Traditional Compressive Sensing (CS obstruction. Compressed Sensing (CS) replaces the combination of high-resolution sampling and nonlinear, low processing power and ultra-low power communication schemes. High compression rates of these data

  19. 29 CFR 1926.803 - Compressed air.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 8 2014-07-01 2014-07-01 false Compressed air. 1926.803 Section 1926.803 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Underground Construction, Caissons, Cofferdams and Compressed Air § 1926.803 Compressed...

  20. Tomographic Image Compression Using Multidimensional Transforms.

    ERIC Educational Resources Information Center

    Villasenor, John D.

    1994-01-01

    Describes a method for compressing tomographic images obtained using Positron Emission Tomography (PET) and Magnetic Resonance (MR) by applying transform compression using all available dimensions. This takes maximum advantage of redundancy of the data, allowing significant increases in compression efficiency and performance. (13 references) (KRN)

  1. Robustness of Compressed Sensing in Sensor Networks 

    E-print Network

    Hern, Brett

    2008-05-22

    implications for wireless sensor networks because power and bandwidth are limited resources. Applying the theory of compressed sensing to the sensor network data recovery problem, we describe a measurement scheme by which sensor network data can... and Constrained Optimization...…. 7 Reconstruction Algorithms..…………………..………..... 9 III COMPRESSIVE MEASUREMENT OF SENSOR NETWORKS.......................................................................... 14 Compressive Wireless Sensing...

  2. Compressive video sensors using multichannel imagers

    E-print Network

    Pitsianis, Nikos P.

    Compressive video sensors using multichannel imagers Mohan Shankar,1,2 Nikos P. Pitsianis,1 compression in video through modified sampling strategies using multichannel imaging systems. The redundancies in video streams are exploited through compressive sampling schemes to achieve low power and low complexity

  3. The H.264 Video Compression Andrew Gibson

    E-print Network

    Wehlau, David

    The H.264 Video Compression Standard by Andrew Gibson A project submited to the Department standard, MPEG-4 (AS) 1 . The H.264 recommendation is directed at compressing and coding nat- ural video; there are no tools to manipulate individual objects represented in the video frames. The compression algorithm

  4. Compressive video sensing with limited measurements

    E-print Network

    Compressive video sensing with limited measurements Tao Li Xiaohua Wang Weihe Wang Aggelos K://spiedl.org/terms #12;Compressive video sensing with limited measurements Tao Li Beijing Institute of Technology School Department of EECS Evanston, Illinois 60201 Abstract. Compressive sensing (CS) is an innovative technology

  5. Technical Notes Compressive Sensing and Reconstruction

    E-print Network

    Huang, Xun

    Technical Notes Compressive Sensing and Reconstruction in Measurements with an Aerospace. Introduction COMPRESSIVE sensing is a newly emerging signal-processing method [1,2] in information technologies. In this note, we introduce the fundamentals of compressive sensing and demonstrate its usage by studying

  6. STATISTICAL COMPRESSIVE SENSING OF GAUSSIAN MIXTURE MODELS

    E-print Network

    STATISTICAL COMPRESSIVE SENSING OF GAUSSIAN MIXTURE MODELS By Guoshen Yu and Guillermo Sapiro IMA: 612-626-7370 URL: http://www.ima.umn.edu #12;STATISTICAL COMPRESSIVE SENSING OF GAUSSIAN MIXTURE.S.A. ABSTRACT A new framework of compressive sensing (CS), namely statistical compres- sive sensing (SCS

  7. Identifying Bad Measurements in Compressive Sensing

    E-print Network

    Kung, H. T.

    Identifying Bad Measurements in Compressive Sensing H. T. Kung, Tsung-Han Lin, Dario Vlah Harvard the system of linear equations in compressive sensing is underconstrained, errors introduced by these bad of large nonzero variables. I. INTRODUCTION Compressive sensing has emerged as a major research area due to

  8. Sparse Reconstruction / Compressive Sensing Namrata Vaswani

    E-print Network

    Vaswani, Namrata

    Sparse Reconstruction / Compressive Sensing Namrata Vaswani Department of Electrical and Computer Engineering Iowa State University Namrata Vaswani Sparse Reconstruction / Compressive Sensing 1/ 20 #12;The Reconstruction / Compressive Sensing 2/ 20 #12;Limitation of zero-filling A traditional solution: zero filling

  9. The Four Day School Week. Research Brief

    ERIC Educational Resources Information Center

    Muir, Mike

    2013-01-01

    Can four-day school weeks help districts save money? How do districts overcome the barriers of moving to a four-day week? What is the effect of a four-day week on students, staff and the community? This paper enumerates the benefits for students and teachers of four-day school weeks. Recommendations for implementation of a four-day week are also…

  10. ADVANCED RECIPROCATING COMPRESSION TECHNOLOGY (ARCT)

    SciTech Connect

    Danny M. Deffenbaugh; Klaus Brun; Ralph E. Harris; J. Pete Harrell; Robert J. Mckee; J. Jeffrey Moore; Steven J. Svedeman; Anthony J. Smalley; Eugene L. Broerman; Robert A Hart; Marybeth G. Nored; Ryan S. Gernentz; Shane P. Siebenaler

    2005-12-01

    The U.S. natural gas pipeline industry is facing the twin challenges of increased flexibility and capacity expansion. To meet these challenges, the industry requires improved choices in gas compression to address new construction and enhancement of the currently installed infrastructure. The current fleet of installed reciprocating compression is primarily slow-speed integral machines. Most new reciprocating compression is and will be large, high-speed separable units. The major challenges with the fleet of slow-speed integral machines are: limited flexibility and a large range in performance. In an attempt to increase flexibility, many operators are choosing to single-act cylinders, which are causing reduced reliability and integrity. While the best performing units in the fleet exhibit thermal efficiencies between 90% and 92%, the low performers are running down to 50% with the mean at about 80%. The major cause for this large disparity is due to installation losses in the pulsation control system. In the better performers, the losses are about evenly split between installation losses and valve losses. The major challenges for high-speed machines are: cylinder nozzle pulsations, mechanical vibrations due to cylinder stretch, short valve life, and low thermal performance. To shift nozzle pulsation to higher orders, nozzles are shortened, and to dampen the amplitudes, orifices are added. The shortened nozzles result in mechanical coupling with the cylinder, thereby, causing increased vibration due to the cylinder stretch mode. Valve life is even shorter than for slow speeds and can be on the order of a few months. The thermal efficiency is 10% to 15% lower than slow-speed equipment with the best performance in the 75% to 80% range. The goal of this advanced reciprocating compression program is to develop the technology for both high speed and low speed compression that will expand unit flexibility, increase thermal efficiency, and increase reliability and integrity. Retrofit technologies that address the challenges of slow-speed integral compression are: (1) optimum turndown using a combination of speed and clearance with single-acting operation as a last resort; (2) if single-acting is required, implement infinite length nozzles to address nozzle pulsation and tunable side branch absorbers for 1x lateral pulsations; and (3) advanced valves, either the semi-active plate valve or the passive rotary valve, to extend valve life to three years with half the pressure drop. This next generation of slow-speed compression should attain 95% efficiency, a three-year valve life, and expanded turndown. New equipment technologies that address the challenges of large-horsepower, high-speed compression are: (1) optimum turndown with unit speed; (2) tapered nozzles to effectively reduce nozzle pulsation with half the pressure drop and minimization of mechanical cylinder stretch induced vibrations; (3) tunable side branch absorber or higher-order filter bottle to address lateral piping pulsations over the entire extended speed range with minimal pressure drop; and (4) semi-active plate valves or passive rotary valves to extend valve life with half the pressure drop. This next generation of large-horsepower, high-speed compression should attain 90% efficiency, a two-year valve life, 50% turndown, and less than 0.75 IPS vibration. This program has generated proof-of-concept technologies with the potential to meet these ambitious goals. Full development of these identified technologies is underway. The GMRC has committed to pursue the most promising enabling technologies for their industry.

  11. Tensile, Compression, Open-Hole Compression and Double Cantilever Beam Fracture Toughness Testing of Multiple NASA Langley Research Center Composite Materials

    NASA Technical Reports Server (NTRS)

    Adams, Donald F.

    1999-01-01

    The attached data summarizes the work performed by the Composite Materials Research Group at the University of Wyoming funded by the NASA LaRC Research Grant NAG-1-1294. The work consisted primarily of tension, compression, open-hole compression and double cantilever beam fracture toughness testing performed an a variety of NASA LaRC composite materials. Tests were performed at various environmental conditions and pre-conditioning requirements. The primary purpose of this work was to support the LaRC material development efforts. The data summaries are arranged in chronological order from oldest to newest.

  12. Quantum Bootstrapping via Compressed Quantum Hamiltonian Learning

    E-print Network

    Nathan Wiebe; Christopher Granade; David G. Cory

    2015-03-30

    Recent work has shown that quantum simulation is a valuable tool for learning empirical models for quantum systems. We build upon these results by showing that a small quantum simulators can be used to characterize and learn control models for larger devices for wide classes of physically realistic Hamiltonians. This leads to a new application for small quantum computers: characterizing and controlling larger quantum computers. Our protocol achieves this by using Bayesian inference in concert with Lieb-Robinson bounds and interactive quantum learning methods to achieve compressed simulations for characterization. Whereas Fisher information analysis shows that current methods which employ short-time evolution are suboptimal, interactive quantum learning allows us to overcome this limitation. We illustrate the efficiency of our bootstrapping protocol by showing numerically that an 8-qubit Ising model simulator can be used to calibrate and control a 50 qubit Ising simulator while using only about 750 kilobits of experimental data.

  13. Quantum Bootstrapping via Compressed Quantum Hamiltonian Learning

    NASA Astrophysics Data System (ADS)

    Wiebe, Nathan; Granade, Christopher; Cory, David

    2015-03-01

    Recent work has shown that quantum simulation is a valuable tool for learning empirical models for quantum systems. We build upon these results by showing that a small quantum simulators can be used to characterize and learn control models for larger devices for wide classes of physically realistic Hamiltonians. This leads to a new application for small quantum computers: characterizing and controlling larger quantum computers. Our protocol achieves this by using Bayesian inference in concert with Lieb-Robinson bounds and interactive quantum learning methods to achieve compressed simulations for characterization. Whereas Fisher information analysis shows that current methods which employ short-time evolution are suboptimal, interactive quantum learning allows us to overcome this limitation. We illustrate the efficiency of our bootstrapping protocol by showing numerically that an 8-qubit Ising model simulator can be used to calibrate and control a 50 qubit Ising simulator while using only about 750 kilobits of experimental data.

  14. Compression failure of angle-ply laminates

    NASA Technical Reports Server (NTRS)

    Peel, L. D.; Hyer, M. W.; Shuart, M. J.

    1992-01-01

    Test results from the compression loading of (+ or - Theta/ - or + Theta)(sub 6s) angle-ply IM7-8551-7a specimens, 0 less than or = Theta less than or = 90 degs, are presented. The observed failure strengths and modes are discussed, and typical stress-strain relations shown. Using classical lamination theory and the maximum stress criterion, an attempt is made to predict failure stress as a function of Theta. This attempt results in poor correlation with test results and thus a more advanced model is used. The model, which is based on a geometrically nonlinear theory, and which was taken from previous work, includes the influence of observed layer waviness. The waviness is described by the wave length and the wave amplitude. The theory is briefly described and results from the theory are correlated with test results. It is shown that by using levels of waviness observed in the specimens, the correlation between predictions and observations is good.

  15. Aerosol and cloud relations and weekly cycles over Central Europe

    NASA Astrophysics Data System (ADS)

    Kourtidis, K.; Georgoulias, A.; Alexandri, G.

    2012-04-01

    In this work, the aerosol and cloud relationships and weekly cycle patterns over Central Europe are examined using level-2 aerosol data from the TERRA MODIS satellite instrument to compile a decadal (2000-2010) 0.1 x 0.1 degree resolution gridded dataset as well as and total cloud cover (TCC) TERRA MODIS data and coarser resolution ISCCP TCC data. Aerosols and TCC were found to be positively correlated for all seasons, the slope of the correlation being slightly higher for low AOD values. A co-examination of AOD, TCC and NCAR/NCEP sea level pressure shows that the positive AOD-TCC correlation holds separately in all pressure bins, thus indicating that the correlation is not a synoptic artefact. A study of the weekly cycle of AOD shows that the main part of the positive (i.e. with midweek peak) weekly cycle plume extends over the central part of Central Europe, with the weekly cycle index (WCI) levels gradually decreasing until the weekly cycle becomes negative (i.e. with weekend peak) when moving away. No clear connection between the WCI patterns and topography was found while there is an apparent correlation between positive weekly cycles in summer and population density. A clear Monday minimum appears over regions with high positive WCI. Monday shifts to Tuesday when moving to the East, indicating aerosol transport from the dominating westerly wind flow. The WCI values and the average percent departures (APDs) for the day of weekly maximum and minimum were examined for 22 selected stations from previous ground-based weekly cycle studies. The weekly cycle is positive and statistically significant for only a few stations situated in France, Germany, Czech Republic and Belgium. A comparison with 1 x 1 degree level-3 MODIS TERRA data shows that in most cases level-3 data can give an indication of the local aerosol weekly cycle strength and phase. The satellite derived day of the weekly maximum and minimum is, generally, in line with results from ground-based studies. The seasonal examination of the WCI patterns show that the positive signal over Central Europe is strongest during summer. More interestingly, the amplitude and phasing of the AOD weekly variability agrees with the TCC one, both for MODIS and ISCCP.

  16. Cluster compression algorithm: A joint clustering/data compression concept

    NASA Technical Reports Server (NTRS)

    Hilbert, E. E.

    1977-01-01

    The Cluster Compression Algorithm (CCA), which was developed to reduce costs associated with transmitting, storing, distributing, and interpreting LANDSAT multispectral image data is described. The CCA is a preprocessing algorithm that uses feature extraction and data compression to more efficiently represent the information in the image data. The format of the preprocessed data enables simply a look-up table decoding and direct use of the extracted features to reduce user computation for either image reconstruction, or computer interpretation of the image data. Basically, the CCA uses spatially local clustering to extract features from the image data to describe spectral characteristics of the data set. In addition, the features may be used to form a sequence of scalar numbers that define each picture element in terms of the cluster features. This sequence, called the feature map, is then efficiently represented by using source encoding concepts. Various forms of the CCA are defined and experimental results are presented to show trade-offs and characteristics of the various implementations. Examples are provided that demonstrate the application of the cluster compression concept to multi-spectral images from LANDSAT and other sources.

  17. The effect of changes in compression ratio upon engine performance

    NASA Technical Reports Server (NTRS)

    Sparrow, Stanwood W

    1925-01-01

    This report is based upon engine tests made at the Bureau of Standards during 1920, 1921, 1922, and 1923. The majority of these tests were of aviation engines and were made in the Altitude Laboratory. For a small portion of the work a single cylinder experimental engine was used. This, however, was operated only at sea-level pressures. The report shows that an increase in break horsepower and a decrease in the pounds of fuel used per brake horsepower hour usually results from an increase in compression ratio. This holds true at least up to the highest ratio investigated, 14 to 1, provided there is no serious preignition or detonation at any ratio. To avoid preignition and detonation when employing high-compression ratios, it is often necessary to use some fuel other than gasoline. It has been found that the consumption of some of these fuels in pounds per brake horsepower hour is so much greater than the consumption of gasoline that it offsets the decrease derived from the use of the high-compression ratio. The changes in indicated thermal efficiency with changes in compression ratio are in close agreement with what would be anticipated from a consideration of the air cycle efficiencies at the various ratios. In so far as these tests are concerned there is no evidence that a change in compression ratio produces an appreciable, consistent change in friction horsepower, volumetric efficiency, or in the range of fuel-air ratios over which the engine can operate. The ratio between the heat loss to the jacket water and the heat converted into brake horsepower or indicated horsepower decreases with increase in compression ratio. (author)

  18. Acclimatization in wide dynamic range multichannel compression and linear amplification hearing aids.

    PubMed

    Yund, E William; Roup, Christina M; Simon, Helen J; Bowman, Glen A

    2006-01-01

    Acclimatization was studied in hearing-impaired patients with no previous hearing aid (HA) experience who were fit bilaterally with either wide dynamic range multichannel compression (WDRMCC) or linear amplification (LA) HAs. Throughout 40 weeks of normal HA use, we monitored changes in nonsense syllable perception in speech-spectrum noise. Syllable recognition for WDRMCC users improved by 4.6% over the first 8 weeks, but the 2.2% improvement for LA users was complete in 2 to 4 weeks. Consonant confusion analyses indicated that WDRMCC experience facilitated consonant identification, while LA users primarily changed their response biases. Furthermore, WDRMCC users showed greater improvement for aided than unaided stimuli, while LA users did not. These results demonstrate acclimatization in new users of WDRMCC HAs but not in new users of LA HAs. A switch in amplification type after 32 weeks produced minimal performance change. Thus, acclimatization depended on the type of amplification and the previous amplification experience. PMID:17123191

  19. The Romance Days of the Week: An Underlying Cohesiveness.

    ERIC Educational Resources Information Center

    Holman, Robyn A.

    1994-01-01

    Reexamines the work of earlier scholars on the circumstances accompanying the changes in the names of the days of the week. Syntactic changes as well as the Church's struggle to eradicate the names of the pagan divinities played a great role in effecting these changes. Dual designations, full forms, and condensed ones existed side by side in some…

  20. MAE 124/ESYS 103 Discussion: Week 7 Transportation Alternatives

    E-print Network

    Gille, Sarah T.

    MAE 124/ESYS 103 Discussion: Week 7 Transportation Alternatives 0. San Diego government routes. And today is Bike to Work Day. Let's take a Life Cycle Assessment approach to transportation planning? What steps do we need to pursue? 1. Why does SANDAG care about transportation? Why does UCSD

  1. 75 FR 52211 - Minority Enterprise Development Week, 2010

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-25

    ... the two hundred and thirty-fifth. (Presidential Sig.) [FR Doc. 2010-21294 Filed 8-24-10; 8:45 am... Development Week, 2010 By the President of the United States of America A Proclamation Since our Nation's... tireless work ethic has defined the character of our country. During Minority Enterprise Development...

  2. 2015 WEEKLY BULLETIN DEPARTMENT OF CHEMISTRY, NORTHWESTERN UNIVERSITY

    E-print Network

    2015 WEEKLY BULLETIN DEPARTMENT OF CHEMISTRY, NORTHWESTERN UNIVERSITY EVANSTON, ILLINOIS March 16.pfizercareers.com and apply to job ID 1008805 All over the world, Pfizer colleagues are working together to positively impact;Qualifications · Bachelors of Science degree + 2-5 years of experience, or Masters of Science degree + 1-2 years

  3. Breaking the Mold. An "Education Week" Occasional Series.

    ERIC Educational Resources Information Center

    Education Week, 1995

    1995-01-01

    Eight articles, published in various issues of "Education Week" starting in March 1994 and ending July 1995, track the work of eight educational reform design teams: (1) "Back to the Future" (Lynn Olson)--the virtues and values of the past in a modern context; (2) "A Welcome Change" (Ann Bradley)--instruction school management, and social services…

  4. Future Prospects of Low Compression Ignition Engines

    NASA Astrophysics Data System (ADS)

    Azim, M. A.

    2014-01-01

    This study presents a review and analysis of the effects of compression ratio and inlet air preheating on engine performance in order to assess the future prospects of low compression ignition engines. Regulation of the inlet air preheating allows some control over the combustion process in compression ignition engines. Literature shows that low compression ratio and inlet air preheating are more beneficial to internal combustion engines than detrimental. Even the disadvantages due to low compression ratio are outweighed by the advantages due to inlet air preheating and vice versa.

  5. Video compressive sensing using Gaussian mixture models.

    PubMed

    Yang, Jianbo; Yuan, Xin; Liao, Xuejun; Llull, Patrick; Brady, David J; Sapiro, Guillermo; Carin, Lawrence

    2014-11-01

    A Gaussian mixture model (GMM)-based algorithm is proposed for video reconstruction from temporally compressed video measurements. The GMM is used to model spatio-temporal video patches, and the reconstruction can be efficiently computed based on analytic expressions. The GMM-based inversion method benefits from online adaptive learning and parallel computation. We demonstrate the efficacy of the proposed inversion method with videos reconstructed from simulated compressive video measurements, and from a real compressive video camera. We also use the GMM as a tool to investigate adaptive video compressive sensing, i.e., adaptive rate of temporal compression. PMID:25095253

  6. A Primer on Compressive Sensing Prof. Philip Schniter

    E-print Network

    Schniter, Philip

    A Primer on Compressive Sensing Prof. Philip Schniter Supported in part by NSF grant CCF-1018368;Introduction to compressive sensing What is compressive sensing? Compressive sensing refers to a sampling Phil Schniter (OSU) A Primer on Compressive Sensing ATR 13 3 / 35 #12;Introduction to compressive

  7. CS168: The Modern Algorithmic Toolbox Lecture #13: Compressive Sensing

    E-print Network

    Boneh, Dan

    CS168: The Modern Algorithmic Toolbox Lecture #13: Compressive Sensing Tim Roughgarden & Gregory to vector sparsity. 2 The Idea and Applications of Compressive Sensing The usual approach to compressing of compressive sensing, also called "compressed sensing," is to directly capture data in a compressed form

  8. [Medical image compression: a review].

    PubMed

    Noreña, Tatiana; Romero, Eduardo

    2013-01-01

    Modern medicine is an increasingly complex activity , based on the evidence ; it consists of information from multiple sources : medical record text , sound recordings , images and videos generated by a large number of devices . Medical imaging is one of the most important sources of information since they offer comprehensive support of medical procedures for diagnosis and follow-up . However , the amount of information generated by image capturing gadgets quickly exceeds storage availability in radiology services , generating additional costs in devices with greater storage capacity . Besides , the current trend of developing applications in cloud computing has limitations, even though virtual storage is available from anywhere, connections are made through internet . In these scenarios the optimal use of information necessarily requires powerful compression algorithms adapted to medical activity needs . In this paper we present a review of compression techniques used for image storage , and a critical analysis of them from the point of view of their use in clinical settings. PMID:23715317

  9. FRC Adiabatic Compression Heating Experiments

    NASA Astrophysics Data System (ADS)

    Degnan, J. H.; Frese, M. H.; Amdahl, D. J.; Babineau, M.; Camacho, J. F.; Coffey, S. K.; Domonkos, M.; Frese, S. D.; Gale, D.; Grabowski, C.; Parker, J. V.; Ralph, D.; Ruden, E. L.; Sommars, W.; Intrator, T. P.; Wurden, G. A.; Sieck, P.; Turchi, P. J.; Waganaar, W. J.; Siemon, R. E.; Awe, T. J.; Bauer, B. S.; Oxner, A.; Lynn, A. G.; Roderick, N. F.

    2007-11-01

    AFRL and LANL are developing Magnetized Target Fusion (MTF). This will use the Shiva Star capacitor bank at AFRL to implode an Al solid liner containing the target plasma to raise density and temperature. The Field Reversed Configuration (FRC) has been chosen for the target because of its stability, translatability, and divertor-like field configuration. The FRX-L experiments at LANL explore FRC formation and translation into the liner. 2D-MHD calculations with MACH2 look at translation, capturing and compressing the FRC. Extended MHD examines FRC rotation. The aforementioned guide the design of the experiment at AFRL, which called FRCHX. Formation and translation tests at AFRL are underway before the first compression heating experiment. Supported by DOE-OFES.

  10. Compressive wideband microwave radar holography

    NASA Astrophysics Data System (ADS)

    Wilson, Scott A.; Narayanan, Ram M.

    2014-05-01

    Compressive sensing has emerged as a topic of great interest for radar applications requiring large amounts of data storage. Typically, full sets of data are collected at the Nyquist rate only to be compressed at some later point, where information-bearing data are retained and inconsequential data are discarded. However, under sparse conditions, it is possible to collect data at random sampling intervals less than the Nyquist rate and still gather enough meaningful data for accurate signal reconstruction. In this paper, we employ sparse sampling techniques in the recording of digital microwave holograms over a two-dimensional scanning aperture. Using a simple and fast non-linear interpolation scheme prior to image reconstruction, we show that the reconstituted image quality is well-retained with limited perceptual loss.

  11. Chapter 22: Compressed Air Evaluation Protocol

    SciTech Connect

    Benton, N.

    2014-11-01

    Compressed-air systems are used widely throughout industry for many operations, including pneumatic tools, packaging and automation equipment, conveyors, and other industrial process operations. Compressed-air systems are defined as a group of subsystems composed of air compressors, air treatment equipment, controls, piping, pneumatic tools, pneumatically powered machinery, and process applications using compressed air. A compressed-air system has three primary functional subsystems: supply, distribution, and demand. Air compressors are the primary energy consumers in a compressed-air system and are the primary focus of this protocol. The two compressed-air energy efficiency measures specifically addressed in this protocol are: high-efficiency/variable speed drive (VSD) compressor replacing modulating compressor; compressed-air leak survey and repairs. This protocol provides direction on how to reliably verify savings from these two measures using a consistent approach for each.

  12. Compressed air energy storage system

    DOEpatents

    Ahrens, Frederick W. (Naperville, IL); Kartsounes, George T. (Naperville, IL)

    1981-01-01

    An internal combustion reciprocating engine is operable as a compressor during slack demand periods utilizing excess power from a power grid to charge air into an air storage reservoir and as an expander during peak demand periods to feed power into the power grid utilizing air obtained from the air storage reservoir together with combustible fuel. Preferably the internal combustion reciprocating engine is operated at high pressure and a low pressure turbine and compressor are also employed for air compression and power generation.

  13. Compressed air energy storage system

    SciTech Connect

    Ahrens, F.W.; Kartsounes, G.T.

    1981-07-28

    An internal combustion reciprocating engine is operable as a compressor during slack demand periods utilizing excess power from a power grid to charge air into an air storage reservoir and as an expander during peak demand periods to feed power into the power grid utilizing air obtained from the air storage reservoir together with combustible fuel. Preferably the internal combustion reciprocating engine is operated at high pressure and a low pressure turbine and compressor are also employed for air compression and power generation.

  14. Radar imaging with compressed sensing

    NASA Astrophysics Data System (ADS)

    Harding, Brian J.; Milla, Marco

    2013-09-01

    A novel technique for radar-imaging inversions is proposed which leverages ideas from the emerging field of compressed sensing. This new method takes advantage of the transform sparsity inherent in natural images. Theoretical recovery results are promising and are borne out by simulations in which this technique outperforms Capon's method and the Maximum Entropy method. Preliminary results using data collected at the Jicamarca Radio Observatory are also presented.

  15. On-line data compression

    SciTech Connect

    Galambos, G.; Bekesi, J.; Pferschy, U.; Woginger, G.

    1994-12-31

    Text compression problems are considered where substrings are substituted by code-words according to a static dictionary such that the original text is encoded by shorter code sequence. In the first part we give sharp worst-case ratios for the longest matching and the (Differential) Greedy Algorithm in case of certain dictionaries. We define a new type algorithm, the Fractional Greedy Algorithm, and we investigate its worst-case behaviour. Finally, we mention some open problems.

  16. Compressing TV-image data

    NASA Technical Reports Server (NTRS)

    Hilbert, E. E.; Lee, J.; Rice, R. F.; Schlutsmeyer, A. P.

    1981-01-01

    Compressing technique calculates activity estimator for each segment of image line. Estimator is used in conjunction with allowable bits per line, N, to determine number of bits necessary to code each segment and which segments can tolerate truncation. Preprocessed line data are then passed to adaptive variable-length coder, which selects optimum transmission code. Method increases capacity of broadcast and cable television transmissions and helps reduce size of storage medium for video and digital audio recordings.

  17. Snapshot colored compressive spectral imager.

    PubMed

    Correa, Claudia V; Arguello, Henry; Arce, Gonzalo R

    2015-10-01

    Traditional spectral imaging approaches require sensing all the voxels of a scene. Colored mosaic FPA detector-based architectures can acquire sets of the scene's spectral components, but the number of spectral planes depends directly on the number of available filters used on the FPA, which leads to reduced spatiospectral resolutions. Instead of sensing all the voxels of the scene, compressive spectral imaging (CSI) captures coded and dispersed projections of the spatiospectral source. This approach mitigates the resolution issues by exploiting optical phenomena in lenses and other elements, which, in turn, compromise the portability of the devices. This paper presents a compact snapshot colored compressive spectral imager (SCCSI) that exploits the benefits of the colored mosaic FPA detectors and the compression capabilities of CSI sensing techniques. The proposed optical architecture has no moving parts and can capture the spatiospectral information of a scene in a single snapshot by using a dispersive element and a color-patterned detector. The optical and the mathematical models of SCCSI are presented along with a testbed implementation of the system. Simulations and real experiments show the accuracy of SCCSI and compare the reconstructions with those of similar CSI optical architectures, such as the CASSI and SSCSI systems, resulting in improvements of up to 6 dB and 1 dB of PSNR, respectively. PMID:26479928

  18. Lithological Uncertainty Expressed by Normalized Compression Distance

    NASA Astrophysics Data System (ADS)

    Jatnieks, J.; Saks, T.; Delina, A.; Popovs, K.

    2012-04-01

    Lithological composition and structure of the Quaternary deposits is highly complex and heterogeneous in nature, especially as described in borehole log data. This work aims to develop a universal solution for quantifying uncertainty based on mutual information shared between the borehole logs. This approach presents tangible information directly useful in generalization of the geometry and lithology of the Quaternary sediments for use in regional groundwater flow models as a qualitative estimate of lithological uncertainty involving thousands of borehole logs would be humanly impossible due to the amount of raw data involved. Our aim is to improve parametrization of recharge in the Quaternary strata. This research however holds appeal for other areas of reservoir modelling, as demonstrated in the 2011 paper by Wellmann & Regenauer-Lieb. For our experiments we used extracts of the Quaternary strata from general-purpose geological borehole log database maintained by the Latvian Environment, Geology and Meteorology Centre, spanning the territory of Latvia. Lithological codes were generalised into 2 aggregation levels consisting of 5 and 20 rock types respectively. Our calculation of borehole log similarity relies on the concept of information distance proposed by Bennet et al. in 1998. This was developed into a practical data mining application by Cilibrasi in the 2007 dissertation. The resulting implementation called CompLearn utilities provide a calculation of the Normalized Compression Distance (NCD) metric. It relies on the universal data compression algorithms for estimating mutual information content in the data. This approach has proven to be universally successful for parameter free data mining in disciplines from molecular biology to network intrusion monitoring. To improve this approach for use in geology it is beneficial to apply several transformations as pre-processing steps to the borehole log data. Efficiency of text stream compressors, such as prediction by partial matching (PPM), used for computing the NCD metric, is highly dependant on context. We assign unique symbols for aggregate lithology types and serialize the borehole logs into text strings, where the string length represents a normalized borehole depth. This encoding ensures that both lithology types as well as depth and sequence of strata is comparable in a form most native to the universal data compression software that calculates the pairwise NCD dissimilarity matrix. The NCD results can be used for generalization of the Quaternary structure using spatial clustering followed by a Voronoi tessellation using boreholes as generator points. After dissolving cluster membership identifiers of the borehole Voronoi polygons in GIS environment, regions representing similar lithological structure can be visualized. The exact number of regions and their homogeneity depends on parameters of the clustering solution. This study is supported by the European Social Fund project No. 2009/0212/1DP/1.1.1.2.0/09/APIA/VIAA/060 Keywords: geological uncertainty, lithological uncertainty, generalization, information distance, normalized compression distance, data compression

  19. Compressive Fracture of Brittle Materials under Divergent Impact Loading

    NASA Astrophysics Data System (ADS)

    Savinykh, A. S.; Kanel, G. I.; Razorenov, S. V.; Rajendran, A.

    2006-07-01

    The main objective of this work was to extend the techniques of shock-wave testing of brittle materials upon divergent loading conditions in order to vary the relationship between longitudinal and transversal stresses and to obtain experimental information about the conditions of the compressive fracture thresholds. Experiments with plane and divergent shock loading of alumina and boron carbide ceramic plates have been carried out. The results of measurements outlined the range of stressed states which are below the failure criterion.

  20. Computed Tomography Image Compressibility and Limitations of Compression Ratio-Based Guidelines.

    PubMed

    Pambrun, Jean-François; Noumeir, Rita

    2015-12-01

    Finding optimal compression levels for diagnostic imaging is not an easy task. Significant compressibility variations exist between modalities, but little is known about compressibility variations within modalities. Moreover, compressibility is affected by acquisition parameters. In this study, we evaluate the compressibility of thousands of computed tomography (CT) slices acquired with different slice thicknesses, exposures, reconstruction filters, slice collimations, and pitches. We demonstrate that exposure, slice thickness, and reconstruction filters have a significant impact on image compressibility due to an increased high frequency content and a lower acquisition signal-to-noise ratio. We also show that compression ratio is not a good fidelity measure. Therefore, guidelines based on compression ratio should ideally be replaced with other compression measures better correlated with image fidelity. Value-of-interest (VOI) transformations also affect the perception of quality. We have studied the effect of value-of-interest transformation and found significant masking of artifacts when window is widened. PMID:25804842

  1. The Effect of Different Concentrations of Chlorhexidine Gluconate on the Compressive Strength of Mineral Trioxide Aggregate

    PubMed Central

    Bidar, Maryam; Eslami, Neda; Naghavi, Neda; Fasihi, Zohreh; Attaran Mashhadi, Negin

    2015-01-01

    Background and aims. Substituting chlorhexidine (CHX) for water has been shown to enhance antimicrobial activity of mineral trioxide aggregate (MTA). The purpose of this study was to compare the compressive strength of MTA mixed with distilled water, 0.12% and 0.2% chlorhexidine. Materials and methods. MTA was mixed according to manufacturer's instructions in group I (n = 20). In groups II & III, 0.12% and 0.2% CHX liquid was substituted for water, respectively. Samples were condensed with moderate force into 20 tubes with 1.5×5 mm dimensions and were allowed to set for 72 hours at 37°C in 100% humidity. After being removed from the molds, their compressive strength was determined using Instron testing machine. Each group was divided into two subgroups according to the time of testing (at 72 hours, and one week). Fractured surfaces of 4 specimens in each group were then evaluated under Scanning Electron Microscope (SEM) to determine their microstructure. One-way ANOVA, Tukey, and paired sample t-test was used for statistical analysis. P < 0.05 was set as significant. Results. There was no significant difference between three groups in terms of their compressive strength after 72 hours. However, the compressive strength of group II was significantly higher than group I (P = 0.034) and group III (P = 0.021) after one week. Crystalline microstructure was similar in all groups. Conclusion. Substitution of 0.012% chlorhexidine for water significantly increased the compressive strength of MTA at 1 week without significant change in crystalline structure. PMID:25973146

  2. Informational Analysis for Compressive Sampling in Radar Imaging

    PubMed Central

    Zhang, Jingxiong; Yang, Ke

    2015-01-01

    Compressive sampling or compressed sensing (CS) works on the assumption of the sparsity or compressibility of the underlying signal, relies on the trans-informational capability of the measurement matrix employed and the resultant measurements, operates with optimization-based algorithms for signal reconstruction and is thus able to complete data compression, while acquiring data, leading to sub-Nyquist sampling strategies that promote efficiency in data acquisition, while ensuring certain accuracy criteria. Information theory provides a framework complementary to classic CS theory for analyzing information mechanisms and for determining the necessary number of measurements in a CS environment, such as CS-radar, a radar sensor conceptualized or designed with CS principles and techniques. Despite increasing awareness of information-theoretic perspectives on CS-radar, reported research has been rare. This paper seeks to bridge the gap in the interdisciplinary area of CS, radar and information theory by analyzing information flows in CS-radar from sparse scenes to measurements and determining sub-Nyquist sampling rates necessary for scene reconstruction within certain distortion thresholds, given differing scene sparsity and average per-sample signal-to-noise ratios (SNRs). Simulated studies were performed to complement and validate the information-theoretic analysis. The combined strategy proposed in this paper is valuable for information-theoretic orientated CS-radar system analysis and performance evaluation. PMID:25811226

  3. Informational analysis for compressive sampling in radar imaging.

    PubMed

    Zhang, Jingxiong; Yang, Ke

    2015-01-01

    Compressive sampling or compressed sensing (CS) works on the assumption of the sparsity or compressibility of the underlying signal, relies on the trans-informational capability of the measurement matrix employed and the resultant measurements, operates with optimization-based algorithms for signal reconstruction and is thus able to complete data compression, while acquiring data, leading to sub-Nyquist sampling strategies that promote efficiency in data acquisition, while ensuring certain accuracy criteria. Information theory provides a framework complementary to classic CS theory for analyzing information mechanisms and for determining the necessary number of measurements in a CS environment, such as CS-radar, a radar sensor conceptualized or designed with CS principles and techniques. Despite increasing awareness of information-theoretic perspectives on CS-radar, reported research has been rare. This paper seeks to bridge the gap in the interdisciplinary area of CS, radar and information theory by analyzing information flows in CS-radar from sparse scenes to measurements and determining sub-Nyquist sampling rates necessary for scene reconstruction within certain distortion thresholds, given differing scene sparsity and average per-sample signal-to-noise ratios (SNRs). Simulated studies were performed to complement and validate the information-theoretic analysis. The combined strategy proposed in this paper is valuable for information-theoretic orientated CS-radar system analysis and performance evaluation. PMID:25811226

  4. A low computational complexity algorithm for ECG signal compression.

    PubMed

    Blanco-Velasco, Manuel; Cruz-Roldán, Fernando; López-Ferreras, Francisco; Bravo-Santos, Angel; Martínez-Muñoz, Damián

    2004-09-01

    In this work, a filter bank-based algorithm for electrocardiogram (ECG) signals compression is proposed. The new coder consists of three different stages. In the first one--the subband decomposition stage--we compare the performance of a nearly perfect reconstruction (N-PR) cosine-modulated filter bank with the wavelet packet (WP) technique. Both schemes use the same coding algorithm, thus permitting an effective comparison. The target of the comparison is the quality of the reconstructed signal, which must remain within predetermined accuracy limits. We employ the most widely used quality criterion for the compressed ECG: the percentage root-mean-square difference (PRD). It is complemented by means of the maximum amplitude error (MAX). The tests have been done for the 12 principal cardiac leads, and the amount of compression is evaluated by means of the mean number of bits per sample (MBPS) and the compression ratio (CR). The implementation cost for both the filter bank and the WP technique has also been studied. The results show that the N-PR cosine-modulated filter bank method outperforms the WP technique in both quality and efficiency. PMID:15271283

  5. Compression behaviour of kappa-carrageenan pellets.

    PubMed

    Ghanam, Dima; Hassan, Issa; Kleinebudde, Peter

    2010-05-10

    The compression behavior of high- and low drug strength pellets containing kappa-carrageenan as pelletisation aid was investigated. Model drugs and fillers with different compression mechanisms were used and the effects of compression force and turret speed were examined. Regardless of the compression behavior of their starting components, all pellet formulations exhibited minimal to absent fragmentation and underwent compression by deformation, confirmed by increased equivalent diameter and aspect ratio and decreased roundness factor of the pellets retrieved after de-aggregation of tablets prepared from lubricated pellets. The retrieved pellets showed also higher fracture resistance in three of the tested formulations and no statistically significant difference in the remaining one thus excluding significant crack formation. A densification mechanism was suggested by decreased total porosity and reduced median pore radius of the compressed pellets. No effect of the process parameters on the degree of pellet deformation was reported. The tensile strength of the tablets prepared from unlubricated pellets increased slightly with increased compression force. Compression of pellets with high density silicified microcrystalline cellulose (SMCC HD 90) as embedding powder protected them from severe deformation and resulted in tablets with sufficient tensile strength, minimal friability, negligible elastic recovery and short disintegration time. The percentage of the pellets and the compression force affected the tensile strength of the prepared tablets whereas no influence of the turret speed and the pre-compression force was observed. PMID:20100553

  6. An Efficient Technique for Text Compression

    E-print Network

    Azad, Md Abul Kalam; Ahmad, Shabbir; Kamruzzaman, S M

    2010-01-01

    For storing a word or the whole text segment, we need a huge storage space. Typically a character requires 1 Byte for storing it in memory. Compression of the memory is very important for data management. In case of memory requirement compression for text data, lossless memory compression is needed. We are suggesting a lossless memory requirement compression method for text data compression. The proposed compression method will compress the text segment or the text file based on two level approaches firstly reduction and secondly compression. Reduction will be done using a word lookup table not using traditional indexing system, then compression will be done using currently available compression methods. The word lookup table will be a part of the operating system and the reduction will be done by the operating system. According to this method each word will be replaced by an address value. This method can quite effectively reduce the size of persistent memory required for text data. At the end of the first l...

  7. Algorithmic height compression of unordered trees.

    PubMed

    Ben-Naoum, Farah; Godin, Christophe

    2016-01-21

    By nature, tree structures frequently present similarities between their sub-parts. Making use of this redundancy, different types of tree compression techniques have been designed in the literature to reduce the complexity of tree structures. A popular and efficient way to compress a tree consists of merging its isomorphic subtrees, which produces a directed acyclic graph (DAG) equivalent to the original tree. An important property of this method is that the compressed structure (i.e. the DAG) has the same height as the original tree, thus limiting partially the possibility of compression. In this paper we address the problem of further compressing this DAG in height. The difficulty is that compression must be carried out on substructures that are not exactly isomorphic as they are strictly nested within each-other. We thus introduced a notion of quasi-isomorphism between subtrees that makes it possible to define similar patterns along any given path in a tree. We then proposed an algorithm to detect these patterns and to merge them, thus leading to compressed structures corresponding to DAGs augmented with return edges. In this way, redundant information is removed from the original tree in both width and height, thus achieving minimal structural compression. The complete compression algorithm is then illustrated on the compression of various plant-like structures. PMID:26551155

  8. Vacation Work, Internships & Work Experience

    E-print Network

    Wapstra, Erik

    Vacation Work, Internships & Work Experience WHAT ARE THEY? Getting first-hand experience and apply your knowledge. Formal vacation work, internships and other types of work experience programs use the period of work experience you have with them as an indicator of your employability

  9. MORBIDITY AND MORTALITY WEEKLY REPORT (MMWR)

    EPA Science Inventory

    The Morbidity and Mortality Weekly Report (MMWR) is used to disseminate weekly provisional data on nationally notifiable infectious diseases. These provisional data are used for program planning and evaluation, monitoring trends in incidence, and detecting disease outbreaks.

  10. Detonation wave compression in gas turbines

    NASA Technical Reports Server (NTRS)

    Wortman, A.

    1986-01-01

    A study was made of the concept of augmenting the performance of low pressure ratio gas turbines by detonation wave compression of part of the flow. The concept exploits the constant volume heat release of detonation waves to increase the efficiency of the Brayton cycle. In the models studied, a fraction of the compressor output was channeled into detonation ducts where it was processed by transient transverse detonation waves. Gas dynamic studies determined the maximum cycling frequency of detonation ducts, proved that upstream propagation of pressure pulses represented no problems and determined the variations of detonation duct output with time. Mixing and wave compression were used to recombine the combustor and detonation duct flows and a concept for a spiral collector to further smooth the pressure and temperature pulses was presented as an optional component. The best performance was obtained with a single firing of the ducts so that the flow could be re-established before the next detonation was initiated. At the optimum conditions of maximum frequency of the detonation ducts, the gas turbine efficiency was found to be 45 percent while that of a corresponding pressure ratio 5 conventional gas turbine was only 26%. Comparable improvements in specific fuel consumption data were found for gas turbines operating as jet engines, turbofans, and shaft output machines. Direct use of the detonation duct output for jet propulsion proved unsatisfactory. Careful analysis of the models of the fluid flow phenomena led to the conclusion that even more elaborate calculations would not diminish the uncertainties in the analysis of the system. Feasibility of the concept to work as an engine now requires validation in an engineering laboratory experiment.

  11. SCHOOL OF COMPUTING CP3108A/B: INDEPENDENT WORK (IW)

    E-print Network

    Stephan, Frank

    SCHOOL OF COMPUTING CP3108A/B: INDEPENDENT WORK (IW) APPLICATION FORM Application for: (please choose one only) ( ) CP3108A: Independent Work (5 hours/week) ­ 2MCs ( ) CP3108B: Independent Work (10 hours/week) ­ 4MCs ( ) Extend CP3108A into CP3108B (5 hours/week) CP3108A will not be recorded

  12. Distributed compressive sensing vs. dynamic compressive sensing: improving the compressive line sensing imaging system through their integration

    NASA Astrophysics Data System (ADS)

    Ouyang, Bing; Hou, Weilin; Caimi, Frank M.; Dalgleish, Fraser R.; Vuorenkoski, Anni K.; Gong, Sue

    2015-05-01

    In recent years, a compressive sensing based underwater imaging system has been under investigation: the Compressive Line Sensing (CLS) imaging system. In the CLS system, each line segment is sensed independently; with regard to signal reconstruction, the correlation among the adjacent lines is exploited via the joint sparsity in the distributed compressive sensing model. Interestingly, the dynamic compressive sensing signal model is also capable of exploiting the correlated nature of the adjacent lines through a Bayesian framework. This paper proposes a new CLS reconstruction technique through the integration of these different models, and includes an evaluation of the proposed technique using the experiment dataset obtained from an underwater imaging test setup.

  13. 78 FR 24323 - National Park Week, 2013

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-24

    ...Proclamation 8961 of April 19, 2013 National Park Week, 2013 By the President of the United States...to be passed on. During National Park Week, we celebrate the wonders entrusted to...summon us to experience it firsthand. This week, the National Park Service will make...

  14. 77 FR 42941 - Captive Nations Week, 2012

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-20

    ...Proclamation 8841--Captive Nations Week, 2012 Memorandum of July 11, 2012...8841 of July 16, 2012 Captive Nations Week, 2012 By the President of the United States...Eisenhower first proclaimed Captive Nations Week amidst an escalating Cold War, he...

  15. 77 FR 62133 - Fire Prevention Week, 2012

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-12

    ...8881 of October 5, 2012 Fire Prevention Week, 2012 By the President of the United States...heartbreaking. During Fire Prevention Week, we resolve to protect ourselves, our...immediately. As we mark Fire Prevention Week by recommitting to preparedness, we...

  16. Understanding Infidelity: An Interview with Gerald Weeks

    ERIC Educational Resources Information Center

    Smith, Travis

    2011-01-01

    In this interview, Gerald Weeks shares his expertise on the topic of infidelity and couples counseling. Dr. Weeks defines infidelity, presents assessment strategies for treating the issue of infidelity, and discusses an intersystemic model for infidelity treatment when counseling couples. Dr. Weeks also provides insight into common mistakes made…

  17. 75 FR 20885 - National Park Week, 2010

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-21

    ... hundred and thirty-fourth. (Presidential Sig.) [FR Doc. 2010-9413 Filed 4-20-10; 11:15 am] Billing code... Proclamation 8498--National Park Week, 2010 Proclamation 8499--National Crime Victims' Rights Week, 2010 Proclamation 8500--National Volunteer Week, 2010 Proclamation 8501--National Day of Service and Remembrance...

  18. Neural and hormonal control of arterial pressure during cold exposure in unanesthetized week-old rats

    E-print Network

    Neural and hormonal control of arterial pressure during cold exposure in unanesthetized week and hormonal control of arterial pressure during cold exposure in unanesthetized week-old rats. Am J Physiol in cold-induced bradycar- dia. Previous work has shown that mean arterial pressure (MAP) is maintained

  19. Effects of 8-Week Training on Aerobic Capacity and Swimming Performance of Boys Aged 12 Years

    ERIC Educational Resources Information Center

    Zarzeczny, Ryszard; Kuberski, Mariusz; Deska, Agnieszka; Zarzeczna, Dorota; Rydz, Katarzyna; Lewandowska, Anna; Balchanowski, Tomasz; Bosiacki, Janusz

    2011-01-01

    Study aim: To assess the effects of 8-week endurance training in swimming on work capacity of boys aged 12 years. Material and methods: The following groups of schoolboys aged 12 years were studied: untrained control (UC; n = 14) and those training swimming for two years. The latter ones were subjected to 8-week training in classical style (CS; n…

  20. Poster Presentations: Turning a Lab of the Week into a Culminating Experience

    ERIC Educational Resources Information Center

    Logan, Jennifer L.; Quin~ones, Rosalynn; Sunderland, Deborah P.

    2015-01-01

    An assignment incorporating posters into a second-year analytical chemistry lab is described. Students work in groups and are assigned one of the application-themed weekly laboratories as a topic. Course data acquired for these weekly laboratories are compiled into spreadsheets that the poster group then analyzes to present in an on-campus poster…

  1. 3 CFR 8981 - Proclamation 8981 of May 17, 2013. National Safe Boating Week, 2013

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 3 The President 1 2014-01-01 2014-01-01 false Proclamation 8981 of May 17, 2013. National Safe..., 2013 Proc. 8981 National Safe Boating Week, 2013By the President of the United States of America A... boating responsibly. We highlight that important work during National Safe Boating Week, and we...

  2. Compression of protein sequence databases.

    PubMed

    Strelets, V B; Lim, H A

    1995-10-01

    We have created an algorithm for compressing a PIR database to assist individual researchers and software developers who utilize sequence database information but may not have huge storage space. The resulting compact databank contains compressed PIR information and an interface written in C which allows fast direct access to the stored information without extensive decompression of corresponding files. The databank files as well as the interface C-file can be used on both PC-compatibles and UNIX-based computers without any modifications. The interface supports all standard PIR Request Network queries (i.e. gets databank SEQ number by entry; for a defined databank SEQ number, gets specified information like: name, organism(s), keyword(s), sequence, sequence features with coordinates, etc.). In contrast with PIR Request Network, our package allows us to call PIR-contained information directly from the C programs, even on a personal computer not on a network. Our PIR-derived databank, SAGITTARIUS PIR, was implemented in the form of separate file sets. Each file set contains database information of independent types (i.e. sequences, entry indexes, organisms, etc.). On a particular computer, the available configuration of the PIR information (and storage space) can be easily changed as needed by the user without affecting retrievals of other types of stored information. Due to an original alignment-based algorithm, in the compression of protein sequences themselves, our package out-performs the well-known ZIP file compressor. For PC-compatibles, a dialogue shell is available which supports all standard PIR Request Network queries plus homology searches, alignments, etc. PMID:8590180

  3. Industrial Compressed Air System Energy Efficiency Guidebook.

    SciTech Connect

    United States. Bonneville Power Administration.

    1993-12-01

    Energy efficient design, operation and maintenance of compressed air systems in industrial plants can provide substantial reductions in electric power and other operational costs. This guidebook will help identify cost effective, energy efficiency opportunities in compressed air system design, re-design, operation and maintenance. The guidebook provides: (1) a broad overview of industrial compressed air systems, (2) methods for estimating compressed air consumption and projected air savings, (3) a description of applicable, generic energy conservation measures, and, (4) a review of some compressed air system demonstration projects that have taken place over the last two years. The primary audience for this guidebook includes plant maintenance supervisors, plant engineers, plant managers and others interested in energy management of industrial compressed air systems.

  4. Compressed sensing for bioelectric signals: a review.

    PubMed

    Craven, Darren; McGinley, Brian; Kilmartin, Liam; Glavin, Martin; Jones, Edward

    2015-03-01

    This paper provides a comprehensive review of compressed sensing or compressive sampling (CS) in bioelectric signal compression applications. The aim is to provide a detailed analysis of the current trends in CS, focusing on the advantages and disadvantages in compressing different biosignals and its suitability for deployment in embedded hardware. Performance metrics such as percent root-mean-squared difference (PRD), signal-to-noise ratio (SNR), and power consumption are used to objectively quantify the capabilities of CS. Furthermore, CS is compared to state-of-the-art compression algorithms in compressing electrocardiogram (ECG) and electroencephalography (EEG) as examples of typical biosignals. The main technical challenges associated with CS are discussed along with the predicted future trends. PMID:24879647

  5. Neural network image compression using Gabor primitives

    NASA Astrophysics Data System (ADS)

    Anderson, Mary P.; Brown, David G.; Schneider, Alexander C.

    1992-06-01

    A back propagation neural network was used to compress simulated nuclear medicine liver images with and without simulated lesions. The network operated on the Gabor representation of the image, in order to take advantage of the apparent similarity between that representation and the natural image processing of the human visual system. The quality of the compression scheme was assessed objectively by comparing the original images to the compressed/reconstructed images through calculation of an index shown to track with human observers for this class of image, the Hotelling trace. Task performance was measured pre- and post-compression for the task of classifying normal versus abnormal livers. Compression of even 2:1 was found to result in significant performance degradation in comparison with other means of compression, but produced a visually pleasing image.

  6. Fuzzy Relational Compression Applied on Feature Vectors for Infant Cry Recognition

    NASA Astrophysics Data System (ADS)

    Reyes-Galaviz, Orion Fausto; Reyes-García, Carlos Alberto

    Data compression is always advisable when it comes to handling and processing information quickly and efficiently. There are two main problems that need to be solved when it comes to handling data; store information in smaller spaces and processes it in the shortest possible time. When it comes to infant cry analysis (ICA), there is always the need to construct large sound repositories from crying babies. Samples that have to be analyzed and be used to train and test pattern recognition algorithms; making this a time consuming task when working with uncompressed feature vectors. In this work, we show a simple, but efficient, method that uses Fuzzy Relational Product (FRP) to compresses the information inside a feature vector, building with this a compressed matrix that will help us recognize two kinds of pathologies in infants; Asphyxia and Deafness. We describe the sound analysis, which consists on the extraction of Mel Frequency Cepstral Coefficients that generate vectors which will later be compressed by using FRP. There is also a description of the infant cry database used in this work, along with the training and testing of a Time Delay Neural Network with the compressed features, which shows a performance of 96.44% with our proposed feature vector compression.

  7. Compressed sensing for Hamiltonian reconstruction

    NASA Astrophysics Data System (ADS)

    Rudinger, Kenneth; Joynt, Robert

    2015-11-01

    In engineered quantum systems, the Hamiltonian is often not completely known and needs to be determined experimentally with accuracy and efficiency. We show that this may be done at temperatures that are higher than the characteristic interaction energies, but not too much higher. The condition for this is that there are not too many multiparticle interactions: the Hamiltonian is sparse in a well-defined sense. The protocol that accomplishes this is related to compressed sensing methods of classical signal processing, in this case applied to sparse rather than low-rank matrices.

  8. Vapor Compression Distillation Flight Experiment

    NASA Technical Reports Server (NTRS)

    Hutchens, Cindy F.

    2002-01-01

    One of the major requirements associated with operating the International Space Station is the transportation -- space shuttle and Russian Progress spacecraft launches - necessary to re-supply station crews with food and water. The Vapor Compression Distillation (VCD) Flight Experiment, managed by NASA's Marshall Space Flight Center in Huntsville, Ala., is a full-scale demonstration of technology being developed to recycle crewmember urine and wastewater aboard the International Space Station and thereby reduce the amount of water that must be re-supplied. Based on results of the VCD Flight Experiment, an operational urine processor will be installed in Node 3 of the space station in 2005.

  9. Krylov methods for compressible flows

    NASA Technical Reports Server (NTRS)

    Tidriri, M. D.

    1995-01-01

    We investigate the application of Krylov methods to compressible flows, and the effect of implicit boundary conditions on the implicit solution of nonlinear problems. Two defect-correction procedures, namely, approximate factorization (AF) for structured grids and ILU/GMRES for general grids, are considered. Also considered here are Newton-Krylov matrix-free methods that we combined with the use of mixed discretization schemes in the implicitly defined Jacobian and its preconditioner. Numerical experiments that show the performance of our approaches are then presented.

  10. Data compression in the petascale astronomy era: A GERLUMPH case study

    NASA Astrophysics Data System (ADS)

    Vohl, D.; Fluke, C. J.; Vernardos, G.

    2015-09-01

    As the volume of data grows, astronomers are increasingly faced with choices on what data to keep-and what to throw away. Recent work evaluating the JPEG2000 (ISO/IEC 15444) standards as a future data format standard in astronomy has shown promising results on observational data. However, there is still a need to evaluate its potential on other type of astronomical data, such as from numerical simulations. GERLUMPH (the GPU-Enabled High Resolution cosmological MicroLensing parameter survey) represents an example of a data intensive project in theoretical astrophysics. In the next phase of processing, the ? 27 terabyte GERLUMPH dataset is set to grow by a factor of 100-well beyond the current storage capabilities of the supercomputing facility on which it resides. In order to minimize bandwidth usage, file transfer time, and storage space, this work evaluates several data compression techniques. Specifically, we investigate off-the-shelf and custom lossless compression algorithms as well as the lossy JPEG2000 compression format. Results of lossless compression algorithms on GERLUMPH data products show small compression ratios (1.35:1 to 4.69:1 of input file size) varying with the nature of the input data. Our results suggests that JPEG2000 could be suitable for other numerical datasets stored as gridded data or volumetric data. When approaching lossy data compression, one should keep in mind the intended purposes of the data to be compressed, and evaluate the effect of the loss on future analysis. In our case study, lossy compression and a high compression ratio do not significantly compromise the intended use of the data for constraining quasar source profiles from cosmological microlensing.

  11. Sparsity and Compressed Coding in Sensory Systems

    PubMed Central

    Barranca, Victor J.; Kova?i?, Gregor; Zhou, Douglas; Cai, David

    2014-01-01

    Considering that many natural stimuli are sparse, can a sensory system evolve to take advantage of this sparsity? We explore this question and show that significant downstream reductions in the numbers of neurons transmitting stimuli observed in early sensory pathways might be a consequence of this sparsity. First, we model an early sensory pathway using an idealized neuronal network comprised of receptors and downstream sensory neurons. Then, by revealing a linear structure intrinsic to neuronal network dynamics, our work points to a potential mechanism for transmitting sparse stimuli, related to compressed-sensing (CS) type data acquisition. Through simulation, we examine the characteristics of networks that are optimal in sparsity encoding, and the impact of localized receptive fields beyond conventional CS theory. The results of this work suggest a new network framework of signal sparsity, freeing the notion from any dependence on specific component-space representations. We expect our CS network mechanism to provide guidance for studying sparse stimulus transmission along realistic sensory pathways as well as engineering network designs that utilize sparsity encoding. PMID:25144745

  12. Improving compressed sensing with the diamond norm

    E-print Network

    Martin Kliesch; Richard Kueng; Jens Eisert; David Gross

    2015-11-04

    In low-rank matrix recovery, one aims to reconstruct a low-rank matrix from a minimal number of linear measurements. Within the paradigm of compressed sensing, this is made computationally efficient by minimizing the nuclear norm as a convex surrogate for rank. In this work, we identify an improved regularizer based on the so-called diamond norm, a concept imported from quantum information theory. We show that - for a class of matrices saturating a certain norm inequality - the descent cone of the diamond norm is contained in that of the nuclear norm. This suggests superior reconstruction properties for these matrices and we explicitly characterize this set. We demonstrate numerically that the diamond norm indeed outperforms the nuclear norm in a number of relevant applications: These include signal analysis tasks such as blind matrix deconvolution or the retrieval of certain unitary basis changes, as well as the quantum information problem of process tomography with random measurements. The diamond norm is defined for matrices that can be interpreted as order-4 tensors and it turns out that the above condition depends crucially on that tensorial structure. In this sense, this work touches on an aspect of the notoriously difficult tensor completion problem.

  13. Evaluation of a novel eyelid-warming device in meibomian gland dysfunction unresponsive to traditional warm compress treatment: an in vivo confocal study.

    PubMed

    Villani, Edoardo; Garoli, Elena; Canton, Veronica; Pichi, Francesco; Nucci, Paolo; Ratiglia, Roberto

    2015-06-01

    The purpose of the study was to evaluate the efficacy and safety of wet chamber warming goggles (Blephasteam(®)) in patients with meibomian gland dysfunction (MGD) unresponsive to warm compress treatment. We consecutively enrolled 50 adult patients with low-delivery, non-cicatricial, MGD, and we instructed them to apply warm compresses twice a day for 10 min for 3 weeks and to use Blephasteam(®) (Laboratoires Thea, Clermont-Ferrand, France) twice a day for 10 min for the following 3 weeks. We considered "not-responders" to warm compress treatment the patients who showed no clinically significant Ocular Surface Disease Index (OSDI) improvement after the first 3 weeks. Clinical and in vivo confocal outcome measures were assessed in the worst eye (lower BUT) at baseline, after 3 weeks, and after 6 weeks. Eighteen/50 patients were not-responders to warm compress treatment. These patients, after 3 weeks of treatment with Blephasteam(®), showed significant improvement of OSDI score (36.4 ± 15.8 vs 20.2 ± 12.4; P < 0.05, paired samples t test), increased BUT (3.4 ± 1.6 vs 7.6 ± 2.7; P < 0.05), and decreased acinar diameter and area (98.4 ± 18.6 vs 64.5 ± 14.4 and 8,037 ± 1,411 vs 5,532 ± 1,172, respectively; P < 0.05). Neither warm compresses nor Blephasteam(®) determined adverse responses. In conclusion, eyelid warming is the mainstay of the clinical treatment of MGD and its poor results may be often due to lack of compliance and standardization. Blephasteam(®) wet chamber warming goggles are a promising alternative to classical warm compress treatment, potentially able to improve the effectiveness of the "warming approach." PMID:24752646

  14. Eccentric crank variable compression ratio mechanism

    DOEpatents

    Lawrence, Keith Edward (Kobe, JP); Moser, William Elliott (Peoria, IL); Roozenboom, Stephan Donald (Washington, IL); Knox, Kevin Jay (Peoria, IL)

    2008-05-13

    A variable compression ratio mechanism for an internal combustion engine that has an engine block and a crankshaft is disclosed. The variable compression ratio mechanism has a plurality of eccentric disks configured to support the crankshaft. Each of the plurality of eccentric disks has at least one cylindrical portion annularly surrounded by the engine block. The variable compression ratio mechanism also has at least one actuator configured to rotate the plurality of eccentric disks.

  15. Compressed data for the movie industry

    NASA Astrophysics Data System (ADS)

    Tice, Bradley S.

    2013-12-01

    The paper will present a compression algorithm that will allow for both random and non-random sequential binary strings of data to be compressed for storage and transmission of media information. The compression system has direct applications to the storage and transmission of digital media such as movies, television, audio signals and other visual and auditory signals needed for engineering practicalities in such industries.

  16. Subband Coding Methods for Seismic Data Compression

    NASA Technical Reports Server (NTRS)

    Kiely, A.; Pollara, F.

    1995-01-01

    This paper presents a study of seismic data compression techniques and a compression algorithm based on subband coding. The compression technique described could be used as a progressive transmission system, where successive refinements of the data can be requested by the user. This allows seismologists to first examine a coarse version of waveforms with minimal usage of the channel and then decide where refinements are required. Rate-distortion performance results are presented and comparisons are made with two block transform methods.

  17. Foam-like compression behavior of fibrin networks

    E-print Network

    O. V. Kim; Xiaojun Liang; Rustem I. Litvinov; John W. Weisel; Mark S. Alber; Prashant K. Purohit

    2015-08-26

    The rheological properties of fibrin networks have been of long-standing interest. As such there is a wealth of studies of their shear and tensile responses, but their compressive behavior remains unexplored. Here, by characterization of the network structure with synchronous measurement of the fibrin storage and loss moduli at increasing degrees of compression, we show that the compressive behavior of fibrin networks is similar to that of cellular solids. A non-linear stress-strain response of fibrin consists of three regimes: 1) an initial linear regime, in which most fibers are straight, 2) a plateau regime, in which more and more fibers buckle and collapse, and 3) a markedly non-linear regime, in which network densification occurs {{by bending of buckled fibers}} and inter-fiber contacts. Importantly, the spatially non-uniform network deformation included formation of a moving "compression front" along the axis of strain, which segregated the fibrin network into compartments with different fiber densities and structure. The Young's modulus of the linear phase depends quadratically on the fibrin volume fraction while that in the densified phase depends cubically on it. The viscoelastic plateau regime corresponds to a mixture of these two phases in which the fractions of the two phases change during compression. We model this regime using a continuum theory of phase transitions and analytically predict the storage and loss moduli which are in good agreement with the experimental data. Our work shows that fibrin networks are a member of a broad class of natural cellular materials which includes cancellous bone, wood and cork.

  18. Energy efficiency improvements in Chinese compressed airsystems

    SciTech Connect

    McKane, Aimee; Li, Li; Li, Yuqi; Taranto, T.

    2007-06-01

    Industrial compressed air systems use more than 9 percent ofall electricity used in China. Experience in China and elsewhere hasshown that these systems can be much more energy efficient when viewed asa whole system and rather than as isolated components.This paper presentsa summary and analysis of several compressed air system assessments.Through these assessments, typical compressed air management practices inChina are analyzed. Recommendations are made concerning immediate actionsthat China s enterprises can make to improve compressed air systemefficiency using best available technology and managementstrategies.

  19. Elastic compression of nanoparticles with surface energy

    NASA Astrophysics Data System (ADS)

    Ding, Yue; Niu, Xin-Rui; Wang, Gang-Feng

    2015-12-01

    The compression of elastic nanoparticles by two rigid planes is analyzed in the present paper. Through a finite element approach with the incorporation of surface energy, we calculate the elastic field of nanoparticles and obtain the explicit expressions for contact radius and indent depth with respect to the compressive load. It is found that when the contact radius is comparable with the ratio of surface energy density to elastic modulus, surface effect significantly affects the elastic field and the overall compressive response of nanoparticles. This study provides an effective tool to analyze the elastic deformation of nanoparticles, and is helpful to measure their elastic properties through compression.

  20. Compression of rehydratable vegetables and cereals

    NASA Technical Reports Server (NTRS)

    Burns, E. E.

    1978-01-01

    Characteristics of freeze-dried compressed carrots, such as rehydration, volatile retention, and texture, were studied by relating histological changes to textural quality evaluation, and by determining the effects of storage temperature on freeze-dried compressed carrot bars. Results show that samples compressed with a high moisture content undergo only slight structural damage and rehydrate quickly. Cellular disruption as a result of compression at low moisture levels was the main reason for rehydration and texture differences. Products prepared from carrot cubes having 48% moisture compared favorably with a freshly cooked product in cohesiveness and elasticity, but were found slightly harder and more chewy.