NASA Astrophysics Data System (ADS)
Mauroy, A.; Mezi?, I.; Moehlis, J.
2013-10-01
For asymptotically periodic systems, a powerful (phase) reduction of the dynamics is obtained by computing the so-called isochrons, i.e. the sets of points that converge toward the same trajectory on the limit cycle. Motivated by the analysis of excitable systems, a similar reduction has been attempted for non-periodic systems admitting a stable fixed point. In this case, the isochrons can still be defined but they do not capture the asymptotic behavior of the trajectories. Instead, the sets of interest-that we call isostables-are defined in the literature as the sets of points that converge toward the same trajectory on a stable slow manifold of the fixed point. However, it turns out that this definition of the isostables holds only for systems with slow-fast dynamics. Also, efficient methods for computing the isostables are missing. The present paper provides a general framework for the definition and the computation of the isostables of stable fixed points, which is based on the spectral properties of the so-called Koopman operator. More precisely, the isostables are defined as the level sets of a particular eigenfunction of the Koopman operator. Through this approach, the isostables are unique and well-defined objects related to the asymptotic properties of the system. Also, the framework reveals that the isostables and the isochrons are two different but complementary notions which define a set of action-angle coordinates for the dynamics. In addition, an efficient algorithm for computing the isostables is obtained, which relies on the evaluation of Laplace averages along the trajectories. The method is illustrated with the excitable FitzHugh-Nagumo model and with the Lorenz model. Finally, we discuss how these methods based on the Koopman operator framework relate to the global linearization of the system and to the derivation of special Lyapunov functions.
Gravitational fixed points from perturbation theory.
Niedermaier, Max R
2009-09-01
The fixed point structure of the renormalization flow in higher derivative gravity is investigated in terms of the background covariant effective action using an operator cutoff that keeps track of powerlike divergences. Spectral positivity of the gauge fixed Hessian can be satisfied upon expansion in the asymptotically free higher derivative coupling. At one-loop order in this coupling strictly positive fixed points are found for the dimensionless Newton constant g(N) and the cosmological constant lambda, which are determined solely by the coefficients of the powerlike divergences. The renormalization flow is asymptotically safe with respect to this fixed point and settles on a lambda(g(N)) trajectory after O(10) units of the renormalization mass scale to accuracy 10(-7). PMID:19792294
NASA Astrophysics Data System (ADS)
Edler, F.; Ederer, P.
2014-07-01
The paper describes the construction and investigation of multiple fixed-point cells usable for the calibration of thermocouples at temperatures above 1100 C. These fixed-point cells made of pure graphite are characterized by a simple construction as well as by a flexible application. The cylindrical basic mount is equipped with a central hole for the insertion of a thermocouple, and with eight drill holes containing exchangeable cartridges which surround the central bore axially symmetrically. The cartridges are filled with different metal-carbon (Me-C) eutectics: cobalt-carbon (Co-C), nickel-carbon (Ni-C), palladium-carbon (Pd-C), and rhodium-carbon (Rh-C). The melting temperatures of the different Me-C eutectics of the cartridges were compared to the melting temperatures of commonly used Me-C eutectic fixed-point cells of the Physikalisch-Technische Bundesanstalt by using a Pt/Pd thermocouple (Co-C, Ni-C) and Type B thermocouples (Pd-C, Rh-C). The uncertainties () of the emfs measured at the inflection points of the melting curves are in the order of a few V which correspond to temperature equivalents between 0.3 K and 0.6 K. Furthermore, the difference between the melting temperatures of the Co-C and Ni-C cartridges was found to be 4.2 K by using simultaneously two sets of four cartridges filled with the two materials and placed alternately in the eight outer holes of one basic mount.
Imaginary fixed points can be physical.
Zhong, Fan
2012-08-01
It has been proposed that a first-order phase transition driven to happen in the metastable region exhibits scaling and universality near an instability point controlled by an instability fixed point of a φ(3) theory. However, this fixed point has an imaginary value and the renormalization-group flow of the φ(3) coupling diverges at a finite scale. Here combining a momentum-space RG analysis and a nucleation theory near the spinodal point, we show that imaginary rather than real values are physical counterintuitively and thus the imaginary fixed point does control the scaling. PMID:23005808
Fixed point theorems and dissipative processes
NASA Technical Reports Server (NTRS)
Hale, J. K.; Lopes, O.
1972-01-01
The deficiencies of the theories that characterize the maximal compact invariant set of T as asymptotically stable, and that some iterate of T has a fixed point are discussed. It is shown that this fixed point condition is always satisfied for condensing and local dissipative T. Applications are given to a class of neutral functional differential equations.
Anderson Acceleration for Fixed-Point Iterations
Walker, Homer F.
2015-08-31
The purpose of this grant was to support research on acceleration methods for fixed-point iterations, with applications to computational frameworks and simulation problems that are of interest to DOE.
ASIC For Complex Fixed-Point Arithmetic
NASA Technical Reports Server (NTRS)
Petilli, Stephen G.; Grimm, Michael J.; Olson, Erlend M.
1995-01-01
Application-specific integrated circuit (ASIC) performs 24-bit, fixed-point arithmetic operations on arrays of complex-valued input data. High-performance, wide-band arithmetic logic unit (ALU) designed for use in computing fast Fourier transforms (FFTs) and for performing ditigal filtering functions. Other applications include general computations involved in analysis of spectra and digital signal processing.
MOST HOMEOMORPHISMS WITH A FIXED POINT HAVE A CANTOR SET OF FIXED POINTS
Craciun, Gheorghe
2015-01-01
We show that, for any n ≠ 2, most orientation preserving homeomorphisms of the sphere S2n have a Cantor set of fixed points. In other words, the set of such homeomorphisms that do not have a Cantor set of fixed points is of the first Baire category within the set of all homeomorphisms. Similarly, most orientation reversing homeomorphisms of the sphere S2n+1 have a Cantor set of fixed points for any n ≠ 0. More generally, suppose that M is a compact manifold of dimension > 1 and ≠ 4 and ℋ is an open set of homeomorphisms h : M → M such that all elements of ℋ have at least one fixed point. Then we show that most elements of ℋ have a Cantor set of fixed points.
Precise Point Positioning with Partial Ambiguity Fixing
Li, Pan; Zhang, Xiaohong
2015-01-01
Reliable and rapid ambiguity resolution (AR) is the key to fast precise point positioning (PPP). We propose a modified partial ambiguity resolution (PAR) method, in which an elevation and standard deviation criterion are first used to remove the low-precision ambiguity estimates for AR. Subsequently the success rate and ratio-test are simultaneously used in an iterative process to increase the possibility of finding a subset of decorrelated ambiguities which can be fixed with high confidence. One can apply the proposed PAR method to try to achieve an ambiguity-fixed solution when full ambiguity resolution (FAR) fails. We validate this method using data from 450 stations during DOY 021 to 027, 2012. Results demonstrate the proposed PAR method can significantly shorten the time to first fix (TTFF) and increase the fixing rate. Compared with FAR, the average TTFF for PAR is reduced by 14.9% for static PPP and 15.1% for kinematic PPP. Besides, using the PAR method, the average fixing rate can be increased from 83.5% to 98.2% for static PPP, from 80.1% to 95.2% for kinematic PPP respectively. Kinematic PPP accuracy with PAR can also be significantly improved, compared to that with FAR, due to a higher fixing rate. PMID:26067196
Precise Point Positioning with Partial Ambiguity Fixing.
Li, Pan; Zhang, Xiaohong
2015-01-01
Reliable and rapid ambiguity resolution (AR) is the key to fast precise point positioning (PPP). We propose a modified partial ambiguity resolution (PAR) method, in which an elevation and standard deviation criterion are first used to remove the low-precision ambiguity estimates for AR. Subsequently the success rate and ratio-test are simultaneously used in an iterative process to increase the possibility of finding a subset of decorrelated ambiguities which can be fixed with high confidence. One can apply the proposed PAR method to try to achieve an ambiguity-fixed solution when full ambiguity resolution (FAR) fails. We validate this method using data from 450 stations during DOY 021 to 027, 2012. Results demonstrate the proposed PAR method can significantly shorten the time to first fix (TTFF) and increase the fixing rate. Compared with FAR, the average TTFF for PAR is reduced by 14.9% for static PPP and 15.1% for kinematic PPP. Besides, using the PAR method, the average fixing rate can be increased from 83.5% to 98.2% for static PPP, from 80.1% to 95.2% for kinematic PPP respectively. Kinematic PPP accuracy with PAR can also be significantly improved, compared to that with FAR, due to a higher fixing rate. PMID:26067196
Fixed points and FLRW cosmologies: Flat case
NASA Astrophysics Data System (ADS)
Awad, Adel
2013-05-01
We use a phase space approach to study possible consequences of fixed points in a single fluid flat Friedmann-Lemaître-Robertson-Walker (FLRW) models with pressure p(H), where H is the Hubble parameter. One of these consequences is that a fluid with a differentiable pressure, i.e., a finite adiabatic speed of sound, reaches a fixed point in an infinite time and has no finite-time singularities of types I, II, and III described by Nojiri, Odintsov, and Tsujikawa [Phys. Rev. D 71, 063004 (2005)]. It is impossible for such a fluid to cross the phantom divide in a finite time. We show that a divergent dp/dH, or the speed of sound, is a necessary but not sufficient condition for phantom crossing. We use pressure properties, such as asymptotic behavior and fixed points, to qualitatively describe the entire behavior of a solution in flat FLRW models. We discuss FLRW models with bulk viscosity η˜ρr, in particular, solutions for r=1 and r=1/4 cases, which can be expressed in terms of the Lambert-W function. The last solution behaves as either a nonsingular phantom fluid or a unified dark fluid. Using causality and stability constraints, we show that the universe must end as a de Sitter space. Relaxing the stability constraint leads to a de Sitter universe, an empty universe, or a turnaround solution that reaches a maximum size and then recollapses.
Structure of stochastic dynamics near fixed points
Kwon, Chulan; Ao, Ping; Thouless, David J.
2005-01-01
We analyze the structure of stochastic dynamics near either a stable or unstable fixed point, where the force can be approximated by linearization. We find that a cost function that determines a Boltzmann-like stationary distribution can always be defined near it. Such a stationary distribution does not need to satisfy the usual detailed balance condition but might have instead a divergence-free probability current. In the linear case, the force can be split into two parts, one of which gives detailed balance with the diffusive motion, whereas the other induces cyclic motion on surfaces of constant cost function. By using the Jordan transformation for the force matrix, we find an explicit construction of the cost function. We discuss singularities of the transformation and their consequences for the stationary distribution. This Boltzmann-like distribution may be not unique, and nonlinear effects and boundary conditions may change the distribution and induce additional currents even in the neighborhood of a fixed point. PMID:16141337
Secure Computation with Fixed-Point Numbers
NASA Astrophysics Data System (ADS)
Catrina, Octavian; Saxena, Amitabh
Secure computation is a promising approach to business problems in which several parties want to run a joint application and cannot reveal their inputs. Secure computation preserves the privacy of input data using cryptographic protocols, allowing the parties to obtain the benefits of data sharing and at the same time avoid the associated risks. These business applications need protocols that support all the primitive data types and allow secure protocol composition and efficient application development. Secure computation with rational numbers has been a challenging problem. We present in this paper a family of protocols for multiparty computation with rational numbers using fixed-point representation. This approach offers more efficient solutions for secure computation than other usual representations.
The Split Common Fixed Point Problem for Directed Operators
Censor, Yair; Segal, Alexander
2010-01-01
We propose the split common fixed point problem that requires to find a common fixed point of a family of operators in one space whose image under a linear transformation is a common fixed point of another family of operators in the image space. We formulate and analyze a parallel algorithm for solving this split common fixed point problem for the class of directed operators and note how it unifies and generalizes previously discussed problems and algorithms. PMID:21318099
Floating-to-Fixed-Point Conversion for Digital Signal Processors
NASA Astrophysics Data System (ADS)
Menard, Daniel; Chillet, Daniel; Sentieys, Olivier
2006-12-01
Digital signal processing applications are specified with floating-point data types but they are usually implemented in embedded systems with fixed-point arithmetic to minimise cost and power consumption. Thus, methodologies which establish automatically the fixed-point specification are required to reduce the application time-to-market. In this paper, a new methodology for the floating-to-fixed point conversion is proposed for software implementations. The aim of our approach is to determine the fixed-point specification which minimises the code execution time for a given accuracy constraint. Compared to previous methodologies, our approach takes into account the DSP architecture to optimise the fixed-point formats and the floating-to-fixed-point conversion process is coupled with the code generation process. The fixed-point data types and the position of the scaling operations are optimised to reduce the code execution time. To evaluate the fixed-point computation accuracy, an analytical approach is used to reduce the optimisation time compared to the existing methods based on simulation. The methodology stages are described and several experiment results are presented to underline the efficiency of this approach.
On Quadratic Stochastic Operators Having Three Fixed Points
NASA Astrophysics Data System (ADS)
Saburov, Mansoor; Atikah Yusof, Nur
2016-03-01
We knew that a trajectory of a linear stochastic operator associated with a positive square stochastic matrix starting from any initial point from the simplex converges to a unique fixed point. However, in general, the similar result for a quadratic stochastic operator associated with a positive cubic stochastic matrix does not hold true. In this paper, we provide an example for the quadratic stochastic operator with positive coefficients in which its trajectory may converge to different fixed points depending on initial points.
A new compact fixed-point blackbody furnace
Hiraka, K.; Oikawa, H.; Shimizu, T.; Kadoya, S.; Kobayashi, T.; Yamada, Y.; Ishii, J.
2013-09-11
More and more NMIs are realizing their primary scale themselves with fixed-point blackbodies as their reference standard. However, commercially available fixed-point blackbody furnaces of sufficient quality are not always easy to obtain. CHINO Corp. and NMIJ, AIST jointly developed a new compact fixed-point blackbody furnace. The new furnace has such features as 1) improved temperature uniformity when compared to previous products, enabling better plateau quality, 2) adoption of the hybrid fixed-point cell structure with internal insulation to improve robustness and thereby to extend lifetime, 3) easily ejectable and replaceable heater unit and fixed-point cell design, leading to reduced maintenance cost, 4) interchangeability among multiple fixed points from In to Cu points. The replaceable cell feature facilitates long term maintenance of the scale through management of a group of fixed-point cells of the same type. The compact furnace is easily transportable and therefore can also function as a traveling standard for disseminating the radiation temperature scale, and for maintaining the scale at the secondary level and industrial calibration laboratories. It is expected that the furnace will play a key role of the traveling standard in the anticipated APMP supplementary comparison of the radiation thermometry scale.
Coincidence and fixed points in symmetric spaces under strict contractions
NASA Astrophysics Data System (ADS)
Imdad, M.; Ali, Javid; Khan, Ladlay
2006-08-01
Some common fixed point theorems due to Aamri and El Moutawakil [M. Aamri, D. El Moutawakil, Some new common fixed point theorems under strict contractive conditions, J. Math. Anal. Appl. 270 (2002) 181-188] and Pant and Pant [R.P. Pant, V. Pant, Common fixed points under strict contractive conditions, J. Math. Anal. Appl. 248 (2000) 327-332] proved for strict contractive mappings in metric spaces are extended to symmetric (semi-metric) spaces under tight conditions. Some related results are derived besides discussing illustrative examples which establish the utility of results proved in this note.
47 CFR 101.137 - Interconnection of private operational fixed point-to-point microwave stations.
Code of Federal Regulations, 2012 CFR
2012-10-01
... point-to-point microwave stations. 101.137 Section 101.137 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Technical Standards § 101.137 Interconnection of private operational fixed point-to-point microwave stations....
47 CFR 101.137 - Interconnection of private operational fixed point-to-point microwave stations.
Code of Federal Regulations, 2010 CFR
2010-10-01
... point-to-point microwave stations. 101.137 Section 101.137 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Technical Standards § 101.137 Interconnection of private operational fixed point-to-point microwave stations....
47 CFR 101.137 - Interconnection of private operational fixed point-to-point microwave stations.
Code of Federal Regulations, 2011 CFR
2011-10-01
... point-to-point microwave stations. 101.137 Section 101.137 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Technical Standards § 101.137 Interconnection of private operational fixed point-to-point microwave stations....
47 CFR 101.137 - Interconnection of private operational fixed point-to-point microwave stations.
Code of Federal Regulations, 2014 CFR
2014-10-01
... point-to-point microwave stations. 101.137 Section 101.137 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Technical Standards § 101.137 Interconnection of private operational fixed point-to-point microwave stations....
47 CFR 101.137 - Interconnection of private operational fixed point-to-point microwave stations.
Code of Federal Regulations, 2013 CFR
2013-10-01
... point-to-point microwave stations. 101.137 Section 101.137 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Technical Standards § 101.137 Interconnection of private operational fixed point-to-point microwave stations....
52. Fixed Span, Top Chord at Panel Point 6; diagonal ...
52. Fixed Span, Top Chord at Panel Point 6; diagonal member goes to intermediate connection 7 & then to bottom chord at 8; looking ESE. - Pacific Shortline Bridge, U.S. Route 20,spanning Missouri River, Sioux City, Woodbury County, IA
Fixed point theory for generalized contractions in cone metric spaces
NASA Astrophysics Data System (ADS)
Farajzadeh, A. P.; Amini-Harandi, A.; Baleanu, D.
2012-02-01
In this paper, we prove some fixed point theorems for generalized contractions in cone metric spaces. Our theorems extend some results of Suzuki (2008) [T. Suzuki, A generalized Banach contraction principle that characterizes metric completeness, Proc Amer Math Soc 136(5) (2008), 1861-1869] and Kikkawa and Suzuki (2008) [M. Kikkawa and T. Suzuki, Three fixed point theorems for generalized contractions with constants in complete metric spaces, Nonlinear Anal 69(9) (2008), 2942-2949].
Image integrity authentication scheme based on fixed point theory.
Li, Xu; Sun, Xingming; Liu, Quansheng
2015-02-01
Based on the fixed point theory, this paper proposes a new scheme for image integrity authentication, which is very different from digital signature and fragile watermarking. By the new scheme, the sender transforms an original image into a fixed point image (very close to the original one) of a well-chosen transform and sends the fixed point image (instead of the original one) to the receiver; using the same transform, the receiver checks the integrity of the received image by testing whether it is a fixed point image and locates the tampered areas if the image has been modified during the transmission. A realization of the new scheme is based on Gaussian convolution and deconvolution (GCD) transform, for which an existence theorem of fixed points is proved. The semifragility is analyzed via commutativity of transforms, and three commutativity theorems are found for the GCD transform. Three iterative algorithms are presented for finding a fixed point image with a few numbers of iterations, and for the whole procedure of image integrity authentication; a fragile authentication system and a semifragile one are separately built. Experiments show that both the systems have good performance in transparence, fragility, security, and tampering localization. In particular, the semifragile system can perfectly resist the rotation by a multiple of 90° flipping and brightness attacks. PMID:25420259
Stray thermal influences in zinc fixed-point cells
Rudtsch, S.; Aulich, A.; Monte, C.
2013-09-11
The influence of thermal effects is a major uncertainty contribution to the calibration of Standard Platinum Resistance Thermometers (SPRTs) in fixed-point cells. Axial heat losses strongly depend on the fixed-point temperature, constructional details of cells and SPRTs and the resulting heat transfer between cell, thermometer, furnace and environment. At the zinc point contributions by heat conduction and thermal radiation must be considered. Although the measurement of temperature gradients in the re-entrant well of a fixed-point cell provides very important information about the influence of axial heat losses, further investigations are required for a reliable estimate of the resulting uncertainty contribution. It is shown that specific modifications of a zinc fixed-point cell, following generally accepted principles, may result in systematic deviations of the measured fixed-point temperatures larger than typically stated in the uncertainty budget of National Metrology Institutes (NMIs). The underlying heat transport processes are investigated and the consequences for the construction of zinc cells are discussed.
Stray thermal influences in zinc fixed-point cells
NASA Astrophysics Data System (ADS)
Rudtsch, S.; Aulich, A.; Monte, C.
2013-09-01
The influence of thermal effects is a major uncertainty contribution to the calibration of Standard Platinum Resistance Thermometers (SPRTs) in fixed-point cells. Axial heat losses strongly depend on the fixed-point temperature, constructional details of cells and SPRTs and the resulting heat transfer between cell, thermometer, furnace and environment. At the zinc point contributions by heat conduction and thermal radiation must be considered. Although the measurement of temperature gradients in the re-entrant well of a fixed-point cell provides very important information about the influence of axial heat losses, further investigations are required for a reliable estimate of the resulting uncertainty contribution. It is shown that specific modifications of a zinc fixed-point cell, following generally accepted principles, may result in systematic deviations of the measured fixed-point temperatures larger than typically stated in the uncertainty budget of National Metrology Institutes (NMIs). The underlying heat transport processes are investigated and the consequences for the construction of zinc cells are discussed.
Some fixed point results in cone metric spaces
NASA Astrophysics Data System (ADS)
Shaddad, Fawzia; Noorani, Mohd Salmi Md; Alsulami, Saud M.
2013-11-01
In this paper we prove the existence of unique fxed point and common fixed points of self-mappings in cone metric spaces. We also, extend, unify and generalize several well known comparable results in the existing literature. An example is provided to elucidate the result.
Design and DSP Implementation of Fixed-Point Systems
NASA Astrophysics Data System (ADS)
Coors, Martin; Keding, Holger; Lüthje, Olaf; Meyr, Heinrich
2002-12-01
This article is an introduction to the FRIDGE design environment which supports the design and DSP implementation of fixed-point digital signal processing systems. We present the tool-supported transformation of signal processing algorithms coded in floating-point ANSI C to a fixed-point representation in SystemC. We introduce the novel approach to control and data flow analysis, which is necessary for the transformation. The design environment enables fast bit-true simulation by mapping the fixed-point algorithm to integral data types of the host machine. A speedup by a factor of 20 to 400 can be achieved compared to C++-library-based bit-true simulation. FRIDGE also provides a direct link to DSP implementation by processor specific C code generation and advanced code optimization.
Border collisions inside the stability domain of a fixed point
NASA Astrophysics Data System (ADS)
Avrutin, Viktor; Zhusubaliyev, Zhanybai T.; Mosekilde, Erik
2016-05-01
Recent studies on a power electronic DC/AC converter (inverter) have demonstrated that such systems may undergo a transition from regular dynamics (associated with a globally attracting fixed point of a suitable stroboscopic map) to chaos through an irregular sequence of border-collision events. Chaotic dynamics of an inverter is not suitable for practical purposes. However, the parameter domain in which the stroboscopic map has a globally attracting fixed point has generally been considered to be uniform and suitable for practical use. In the present paper we show that this domain actually has a complicated interior structure formed by boundaries defined by persistence border collisions. We describe a simple approach that is based on symbolic dynamics and makes it possible to detect such boundaries numerically. Using this approach we describe several regions in the parameter space leading to qualitatively different output signals of the inverter although all associated with globally attracting fixed points of the corresponding stroboscopic map.
Fixed-Rate Compressed Floating-Point Arrays.
Lindstrom, Peter
2014-12-01
Current compression schemes for floating-point data commonly take fixed-precision values and compress them to a variable-length bit stream, complicating memory management and random access. We present a fixed-rate, near-lossless compression scheme that maps small blocks of 4(d) values in d dimensions to a fixed, user-specified number of bits per block, thereby allowing read and write random access to compressed floating-point data at block granularity. Our approach is inspired by fixed-rate texture compression methods widely adopted in graphics hardware, but has been tailored to the high dynamic range and precision demands of scientific applications. Our compressor is based on a new, lifted, orthogonal block transform and embedded coding, allowing each per-block bit stream to be truncated at any point if desired, thus facilitating bit rate selection using a single compression scheme. To avoid compression or decompression upon every data access, we employ a software write-back cache of uncompressed blocks. Our compressor has been designed with computational simplicity and speed in mind to allow for the possibility of a hardware implementation, and uses only a small number of fixed-point arithmetic operations per compressed value. We demonstrate the viability and benefits of lossy compression in several applications, including visualization, quantitative data analysis, and numerical simulation. PMID:26356981
Ultraviolet fixed points in conformal gravity and general quadratic theories
NASA Astrophysics Data System (ADS)
Ohta, Nobuyoshi; Percacci, Roberto
2016-02-01
We study the beta functions for four-dimensional conformal gravity using two different parametrizations of metric fluctuation, linear split and exponential parametrization. We find that after imposing the traceless conditions, the beta functions are the same in four dimensions though the dependence on the dimensions are quite different. This indicates the universality of these results. We also examine the beta functions in general quadratic theory with the Einstein and cosmological terms for exponential parametrization, and find that it leads to results for beta functions of dimensionful couplings different from linear split, though the fact that there exists a nontrivial fixed point remains the same and the fixed points also remain the same.
Measurement of thermodynamic temperature of high temperature fixed points
Gavrilov, V. R.; Khlevnoy, B. B.; Otryaskin, D. A.; Grigorieva, I. A.; Samoylov, M. L.; Sapritsky, V. I.
2013-09-11
The paper is devoted to VNIIOFI's measurements of thermodynamic temperature of the high temperature fixed points Co-C, Pt-C and Re-C within the scope of the international project coordinated by the Consultative Committee for Thermometry working group 5 'Radiation Thermometry'. The melting temperatures of the fixed points were measured by a radiance mode radiation thermometer calibrated against a filter radiometer with known irradiance spectral responsivity via a high temperature black body. This paper describes the facility used for the measurements, the results and estimated uncertainties.
Fixed Point Problems for Linear Transformations on Pythagorean Triples
ERIC Educational Resources Information Center
Zhan, M.-Q.; Tong, J.-C.; Braza, P.
2006-01-01
In this article, an attempt is made to find all linear transformations that map a standard Pythagorean triple (a Pythagorean triple [x y z][superscript T] with y being even) into a standard Pythagorean triple, which have [3 4 5][superscript T] as their fixed point. All such transformations form a monoid S* under matrix product. It is found that S*…
Fixed Points of Difference Operator of Meromorphic Functions
Wu, Zhaojun; Xu, Hongyan
2014-01-01
Let f be a transcendental meromorphic function of order less than one. The authors prove that the exact difference Δf =(z+1) - f (z) has infinitely many fixed points, if a ∈ ℂ and ∞ are Borel exceptional values (or Nevanlinna deficiency values) of f. These results extend the related results obtained by Chen and Shon. PMID:24563624
New triple fixed point results in cone metric spaces
NASA Astrophysics Data System (ADS)
Abusalim, Sahar Mohammad; Noorani, Mohd Salmi Md
2015-05-01
The conception of c-distance on a cone metric space was introduced in 2011. In this paper, some tripled fixed points theorems for some type of contraction mapping are evidenced in a cone metric space by using this concept of c-distance. We also provide examples to illustrate our obtained results.
Development of Fixed-Point Cells at the SMU
NASA Astrophysics Data System (ADS)
Ďuriš, S.; Ranostaj, J.; Palenčár, R.
2008-06-01
One of the research programs realized at the thermometry laboratory of the Slovak Institute of Metrology (SMU) in recent years has focused on the development of fixed-point cells. In the frame of this research, several primary cells for realization of the International Temperature Scale of 1990 (ITS-90) and several secondary cells for industrial thermometer calibrations were built and studied. This article discusses primary cells for the gallium and mercury fixed points and miniature cells for the zinc point that were developed at the SMU. Information about the cell designs is provided, the materials that were used are specified, and the procedures for their manufacture are described. Briefly, the realization of the fixed points of mercury, gallium, and zinc by using these cells is also described. Many experiments were carried out to study the characteristics of these cells. One of the gallium cells was compared with the circulating transfer cell during the key comparison CCT-K3, and it and the mercury cell were used for the EUROMET Project No. 552. The results of the experiments together with the results of the comparisons show the high quality of these cells. Secondary zinc-point cells were compared against SMU primary zinc-point cells. The comparison shows agreement within 0.12 mK.
A fixed-point framework for launch vehicle ascent guidance
NASA Astrophysics Data System (ADS)
Zhang, Lijun
Recent interests in responsive launch have highlighted the need for rapid and fully automated ascent guidance planning and guidance parameter generation for launch vehicles. This dissertation aims at developing methodology and algorithms for on-demand generation of optimal launch vehicle ascent trajectories from lift-off to achieving targeting conditions outside the atmosphere. The entire ascent trajectory from lift-off to final target point is divided into two parts: atmospheric ascent portion and vacuum ascent portion. The two portions are integrated via a fixed-point iteration based on the continuity condition at the switch point between atmospheric ascent portion and vacuum ascent portion. The previous research works on closed-loop endo-atmospheric ascent guidance shows that the classical finite difference method is well suited for fast solution of the constrained optimal three-dimensional ascent problem. The exploitation of certain unique features in the integration procedure between the atmospheric portion and vacuum portion and the finite difference method, allows us to cast the atmospheric ascent problem into a nested fixed-point iteration problem. Therefore a novel Fixed-Point Iteration algorithm is presented for solving the endo-atmospheric ascent guidance problem. Several approaches are also provided for facilitating the convergence of the fixed-point iteration. The exo-atmospheric ascent portion allows an optimal coast in between the two vacuum powered stages. The optimal coast enables more efficient usage of the propellant. The Analytical Multiple-Shooting algorithm is developed to find the optimal trajectory for this portion. A generic launch vehicle model is adopted in the numerical simulation. A series of open-loop and closed-loop simulations are performed. The results verify the effectiveness, robustness and reliability of the Fixed-Point Iteration (FPI) algorithm and Analytical Multiple-Shooting (AMS) algorithm developed in this research. In comparison to Finite Difference (FD) algorithm, the Fixed-Point Iteration algorithm is more adaptive to the "cold start" case for endoatmospheric ascent guidance. The simulations also validate the feasibility of the methodology presented in this research in rapid panning and guidance for ascent through atmosphere.
Comparison of Fixed Point Realisations between Inmetro and PTB
NASA Astrophysics Data System (ADS)
Santiago, J. F. N.; Petkovic, S. G.; Teixeira, R. N.; Noatsch, U.; Thiele-Krivoj, B.
2003-09-01
An interlaboratory comparison in the temperature range between -190 °C and 420 °C was organised between the National Institute of Quality, Normalisation and Industrial Quality (Inmetro), Brazil, and the Physikalisch Technische Bundesanstalt (PTB), Germany. This comparison followed the same protocol as the EUROMET project 552 comparison and was carried out in the years 2001-2002. A standard platinum resistance thermometer (SPRT) of 25 Ω was calibrated at the temperature fixed points of Ar, Hg, the triple point of water (TWP), Ga, In, Sn and Zn, with at least three realisations of each fixed point at both institutes. The uncertainty evaluation is given by Inmetro and some differences in the calibration procedures or in the measuring instruments used are described. The agreement between the results of laboratories was not in all cases within the combined uncertainties. Results of other comparisons are presented, which give additional information on the equivalence of the realised temperature scales.
Fixed-rate compressed floating-point arrays
Lindstrom, P.
2014-03-30
ZFP is a library for lossy compression of single- and double-precision floating-point data. One of the unique features of ZFP is its support for fixed-rate compression, which enables random read and write access at the granularity of small blocks of values. Using a C++ interface, this allows declaring compressed arrays (1D, 2D, and 3D arrays are supported) that through operator overloading can be treated just like conventional, uncompressed arrays, but which allow the user to specify the exact number of bits to allocate to the array. ZFP also has variable-rate fixed-precision and fixed-accuracy modes, which allow the user to specify a tolerance on the relative or absolute error.
Fixed-rate compressed floating-point arrays
Energy Science and Technology Software Center (ESTSC)
2014-03-30
ZFP is a library for lossy compression of single- and double-precision floating-point data. One of the unique features of ZFP is its support for fixed-rate compression, which enables random read and write access at the granularity of small blocks of values. Using a C++ interface, this allows declaring compressed arrays (1D, 2D, and 3D arrays are supported) that through operator overloading can be treated just like conventional, uncompressed arrays, but which allow the user tomore » specify the exact number of bits to allocate to the array. ZFP also has variable-rate fixed-precision and fixed-accuracy modes, which allow the user to specify a tolerance on the relative or absolute error.« less
Gravity Duals of Lifshitz-Like Fixed Points
Kachru, Shamit; Liu, Xiao; Mulligan, Michael; /Stanford U., Phys. Dept. /SLAC
2008-11-05
We find candidate macroscopic gravity duals for scale-invariant but non-Lorentz invariant fixed points, which do not have particle number as a conserved quantity. We compute two-point correlation functions which exhibit novel behavior relative to their AdS counterparts, and find holographic renormalization group flows to conformal field theories. Our theories are characterized by a dynamical critical exponent z, which governs the anisotropy between spatial and temporal scaling t {yields} {lambda}{sup z}t, x {yields} {lambda}x; we focus on the case with z = 2. Such theories describe multicritical points in certain magnetic materials and liquid crystals, and have been shown to arise at quantum critical points in toy models of the cuprate superconductors. This work can be considered a small step towards making useful dual descriptions of such critical points.
Fixed points, stable manifolds, weather regimes, and their predictability
Deremble, Bruno; D'Andrea, Fabio; Ghil, Michael
2009-10-27
In a simple, one-layer atmospheric model, we study the links between low-frequency variability and the model’s fixed points in phase space. The model dynamics is characterized by the coexistence of multiple ''weather regimes.'' To investigate the transitions from one regime to another, we focus on the identification of stable manifolds associated with fixed points. We show that these manifolds act as separatrices between regimes. We track each manifold by making use of two local predictability measures arising from the meteorological applications of nonlinear dynamics, namely, ''bred vectors'' and singular vectors. These results are then verified in the framework of ensemble forecasts issued from clouds (ensembles) of initial states. The divergence of the trajectories allows us to establish the connections between zones of low predictability, the geometry of the stable manifolds, and transitions between regimes.
Fixed points, stable manifolds, weather regimes, and their predictability
Deremble, Bruno; D'Andrea, Fabio; Ghil, Michael
2009-10-27
In a simple, one-layer atmospheric model, we study the links between low-frequency variability and the model’s fixed points in phase space. The model dynamics is characterized by the coexistence of multiple ''weather regimes.'' To investigate the transitions from one regime to another, we focus on the identification of stable manifolds associated with fixed points. We show that these manifolds act as separatrices between regimes. We track each manifold by making use of two local predictability measures arising from the meteorological applications of nonlinear dynamics, namely, ''bred vectors'' and singular vectors. These results are then verified in the framework of ensemblemore » forecasts issued from clouds (ensembles) of initial states. The divergence of the trajectories allows us to establish the connections between zones of low predictability, the geometry of the stable manifolds, and transitions between regimes.« less
Thermal analysis on the realization of the tin fixed point
NASA Astrophysics Data System (ADS)
Tsai, S. F.
2013-09-01
A study on the thermal analysis of a new tin fixed-point open cell within a new three-zone furnace was carried out. The stability at the setting temperatures of liquid-solid coexisting together with some degree Celsius lower and higher than the tin fixed point; and the axial uniformity of furnace while tin is still in solid phase were investigated and analyzed. The impurities effect on the depression in temperature was investigated in terms of ΔT (Tobserved-T1/F=0) and the inverse of the melted fraction (1/F) relationship during the melting and the following freezing realizations at various temperature settings of furnace. These thermal analysis results were also compared with those estimated by the CCT-WG1 recommended SIE (sum of individual estimates) method, which leads to a temperature correction along with a corresponding uncertainty through the individual impurity content detected by GDMS (glow discharge mass spectrometry).
Zinc-Filled Multi-entrance Fixed Point
NASA Astrophysics Data System (ADS)
Zvizdic, D.; Sestan, D.
2015-03-01
Comparison calibrations comprise by far the majority of all thermometer calibrations, and the improvement of the calibration speed and quality is of significant importance. In general, these calibrations are performed by comparing a thermometer under calibration with a reference thermometer, with both thermometers being placed in a zone of controlled temperature that is in thermal equilibrium. The time invariance of metrological characteristics of temperature regulated zones (gradients, stability, repeatability) adds a significant contribution to the total calibration uncertainty. To improve spatial thermal homogeneity and temporal stability of ordinary equalizing blocks (commonly used in combination with calibration baths and furnaces), a new concept is developed under the name multi-entrance fixed point (MEFP). With the MEFP, performances are improved by utilizing a phase transition of matter, similar to the fixed-point cells that are used for calibration of thermometers at the primary level. While fixed-point cells represent temperature standards alone, the MEFP concept requires the use of a standard thermometer as the calibration reference. This paper discusses the advantages, design possibilities, and performance of the concept and gives results of the investigation of the zinc-filled MEFP cell. The performance of the new MEFP cell was examined by calibrating a thermometer against a standard. Two calibrations were performed in the same furnace, first using an MEFP cell as an ordinary equalizing block (without a phase transition) and then at the melt plateau of zinc. The investigation results confirmed the usefulness of the MEFP concept, as the uncertainty contributions from temperature gradients and the stability of the furnace were decreased by an order of magnitude, in comparison to the ordinary equalizing block.
Anomalous fixed point behavior'' of two Kondo impurities: A reexamination
Fye, R.M. )
1994-02-07
We consider the existence of anomalous fixed point behavior'' for the Kondo two-impurity Hamiltonian. This anomalous'' behavior is predicted by calculations which use the energy-independent coupling constants'' (ECC) approximation. Using well-controlled quantum Monte Carlo methods without the ECC approximation, we find no evidence for anomalous'' behavior. We then show that the ECC approximation is, in general, either inconsistent or uninteresting. These results together strongly suggest that the predicted anomalous'' behavior of two Kondo impurities is simply the result of an unphysical approximation rather than an intrinsic property of the model itself.
Global solutions of functional fixed point equations via pseudospectral methods
NASA Astrophysics Data System (ADS)
Borchardt, J.; Knorr, B.
2015-05-01
We apply pseudospectral methods to construct global solutions of functional renormalization group equations in field space to high accuracy. For this, we introduce a basis to resolve both finite as well as asymptotic regions of effective potentials. Our approach is benchmarked using the critical behavior of the scalar O (1 ) model, providing results for the global fixed point potential as well as leading critical exponents and their respective global eigenfunctions. We provide new results for (1) multicritical O (1 ) models in fractional dimensions, (2) the three-dimensional Gross-Neveu model at both small and large N , and (3) the scalar-tensor model, also in three dimensions.
Accuracy and Efficiency in Fixed-Point Neural ODE Solvers.
Hopkins, Michael; Furber, Steve
2015-10-01
Simulation of neural behavior on digital architectures often requires the solution of ordinary differential equations (ODEs) at each step of the simulation. For some neural models, this is a significant computational burden, so efficiency is important. Accuracy is also relevant because solutions can be sensitive to model parameterization and time step. These issues are emphasized on fixed-point processors like the ARM unit used in the SpiNNaker architecture. Using the Izhikevich neural model as an example, we explore some solution methods, showing how specific techniques can be used to find balanced solutions. We have investigated a number of important and related issues, such as introducing explicit solver reduction (ESR) for merging an explicit ODE solver and autonomous ODE into one algebraic formula, with benefits for both accuracy and speed; a simple, efficient mechanism for cancelling the cumulative lag in state variables caused by threshold crossing between time steps; an exact result for the membrane potential of the Izhikevich model with the other state variable held fixed. Parametric variations of the Izhikevich neuron show both similarities and differences in terms of algorithms and arithmetic types that perform well, making an overall best solution challenging to identify, but we show that particular cases can be improved significantly using the techniques described. Using a 1 ms simulation time step and 32-bit fixed-point arithmetic to promote real-time performance, one of the second-order Runge-Kutta methods looks to be the best compromise; Midpoint for speed or Trapezoid for accuracy. SpiNNaker offers an unusual combination of low energy use and real-time performance, so some compromises on accuracy might be expected. However, with a careful choice of approach, results comparable to those of general-purpose systems should be possible in many realistic cases. PMID:26313605
A Fixed-Point Iteration Method with Quadratic Convergence
Walker, Kevin P.; Sham, Sam
2012-01-01
The fixed-point iteration algorithm is turned into a quadratically convergent scheme for a system of nonlinear equations. Most of the usual methods for obtaining the roots of a system of nonlinear equations rely on expanding the equation system about the roots in a Taylor series, and neglecting the higher order terms. Rearrangement of the resulting truncated system then results in the usual Newton-Raphson and Halley type approximations. In this paper the introduction of unit root functions avoids the direct expansion of the nonlinear system about the root, and relies, instead, on approximations which enable the unit root functions to considerably widen the radius of convergence of the iteration method. Methods for obtaining higher order rates of convergence and larger radii of convergence are discussed.
Multi-Valued Modal Fixed Point Logics for Model Checking
NASA Astrophysics Data System (ADS)
Nishizawa, Koki
In this paper, I will show how multi-valued logics are used for model checking. Model checking is an automatic technique to analyze correctness of hardware and software systems. A model checker is based on a temporal logic or a modal fixed point logic. That is to say, a system to be checked is formalized as a Kripke model, a property to be satisfied by the system is formalized as a temporal formula or a modal formula, and the model checker checks that the Kripke model satisfies the formula. Although most existing model checkers are based on 2-valued logics, recently new attempts have been made to extend the underlying logics of model checkers to multi-valued logics. I will summarize these new results.
Fixed-Point Optimization of Atoms and Density in DFT.
Marks, L D
2013-06-11
I describe an algorithm for simultaneous fixed-point optimization (mixing) of the density and atomic positions in Density Functional Theory calculations which is approximately twice as fast as conventional methods, is robust, and requires minimal to no user intervention or input. The underlying numerical algorithm differs from ones previously proposed in a number of aspects and is an autoadaptive hybrid of standard Broyden methods. To understand how the algorithm works in terms of the underlying quantum mechanics, the concept of algorithmic greed for different Broyden methods is introduced, leading to the conclusion that if a linear model holds that the first Broyden method is optimal, the second if a linear model is a poor approximation. How this relates to the algorithm is discussed in terms of electronic phase transitions during a self-consistent run which results in discontinuous changes in the Jacobian. This leads to the need for a nongreedy algorithm when the charge density crosses phase boundaries, as well as a greedy algorithm within a given phase. An ansatz for selecting the algorithm structure is introduced based upon requiring the extrapolated component of the curvature condition to have projected positive eigenvalues. The general convergence of the fixed-point methods is briefly discussed in terms of the dielectric response and elastic waves using known results for quasi-Newton methods. The analysis indicates that both should show sublinear dependence with system size, depending more upon the number of different chemical environments than upon the number of atoms, consistent with the performance of the algorithm and prior literature. This is followed by details of algorithm ranging from preconditioning to trust region control. A number of results are shown, finishing up with a discussion of some of the many open questions. PMID:26583869
Composite Higgs model at a conformal fixed point
NASA Astrophysics Data System (ADS)
Brower, R. C.; Hasenfratz, A.; Rebbi, C.; Weinberg, E.; Witzel, O.
2016-04-01
We propose to construct a chirally broken model based on the infrared fixed point of a conformal system by raising the mass of some flavors while keeping the others massless. In the infrared limit, the massive fermions decouple, and the massless fermions break chiral symmetry. The running coupling of this system "walks," and the energy range of walking can be tuned by the mass of the heavy flavors. Renormalization group considerations predict that the spectrum of such a system shows hyperscaling. We have studied a model with four light and eight heavy flavors coupled to S U (3 ) gauge fields and verified the above expectations. We determined the mass of several hadronic states and found that some of them are in the 2-3 TeV range if the scale is set by the pseudoscalar decay constant Fπ≈250 GeV . The 0++ scalar state behaves very differently from the other hadronic states. In most of our simulations, it is nearly degenerate with the pion, and we estimate its mass to be less than half of the vector resonance mass.
Renormalization and fixed points in finance, since 1962
NASA Astrophysics Data System (ADS)
Mandelbrot, Benoit B.
1999-02-01
In diverse sciences that lack Hamiltonians, the analysis of complex systems is helped by the powerful tools provided by renormalization, fixed points and scaling. As one example, an intrinsic form of exact renormalizability was long used by the author in economics and related fields, most notably in finance. In 1962-3, its use led to a model of price variation founded on the (Cauchy-Polyà-Lévy) stable distribution, with striking data collapse that accounted for observed large deviations from Gaussianity. In 1965, a different form of exact renormalization led to fractional Brownian motion, which neglected large deviations but accounted for long dependence and the resulting non periodic cyclic behavior. Finally, from a seed planted in 1972, exact renormalizability and scaling led to a model of price variation of which the M1963 and M1965 models are special examples. This broader model, fractional Brownian motion in multifractal time, accounts simultaneously for both large deviations and long dependence. These three steps are in loose parallelism with space, time and joint renormalization in statistical physics. This presentation surveys the old works and many new developments described in the author's 1997 books on fractals and scaling in finance.
NASA Astrophysics Data System (ADS)
Lampitt, Richard; Cristini, Luisa
2014-05-01
The Fixed point Open Ocean Observatory network (FixO3) seeks to integrate the 23 European open ocean fixed point observatories and to improve access to these key installations for the broader community. These will provide multidisciplinary observations in all parts of the oceans from the air-sea interface to the deep seafloor. Coordinated by the National Oceanography Centre, UK, FixO3 builds on the significant advances achieved through the previous Europe-funded FP7 programmes EuroSITES, ESONET and CARBOOCEAN. Started in September 2013 with a budget of 7 Million Euros over 4 years the project has 29 partners drawn from academia, research institutions and SME's. In addition 12 international experts from a wide range of disciplines comprise an Advisory Board. On behalf of the FixO3 Consortium, we present the programme that will be achieved through the activities of 12 Work Packages: 1. Coordination activities to integrate and harmonise the current procedures and processes. Strong links will be fostered with the wider community across academia, industry, policy and the general public through outreach, knowledge exchange and training. 2. Support actions to offer a) free access to observatory infrastructures to those who do not have such access, and b) free and open data services and products. 3. Joint research activities to innovate and enhance the current capability for multidisciplinary in situ ocean observation. Support actions include Transnational Access (TNA) to FixO3 infrastructure, meaning that European organizations can apply to free-of-charge access to the observatories for research and testing in two international calls during the project lifetime. The first call for TNA opens in summer 2014. More information can be found on FixO3 website (www.fixo3.eu/). Open ocean observation is currently a high priority for European marine and maritime activities. FixO3 will provide important data on environmental products and services to address the Marine Strategy Framework Directive and in support of the European Integrated Maritime Policy. The FixO3 network will provide free and open access to in situ fixed point data of the highest quality. It will provide a strong integrated framework of open ocean facilities in the Atlantic from the Arctic to the Antarctic and throughout the Mediterranean, enabling an integrated, regional and multidisciplinary approach to understand natural and anthropogenic change in the ocean.
Some Extensions of Discrete Fixed Point Theorems and Their Applications to the Game Theory
NASA Astrophysics Data System (ADS)
Kawasaki, Hidefumi
2009-09-01
As is well-known in the game theory, fixed point theorems are useful to show the existence of Nash equilibrium. Since they are mathematical tools in continuous variables, it is expected that discrete fixed point theorems also useful to guarantee the existence of pure-strategy Nash equilibrium. In this talk, we review three types of discrete fixed point theorems, give some extensions, and apply them to non-cooperative games.
NASA Astrophysics Data System (ADS)
Fuentes, Miguel A.; Robledo, A.
2010-12-01
We determine the limit distributions of sums of deterministic chaotic variables in unimodal maps assisted by a novel renormalization group (RG) framework associated to the operation of increment of summands and rescaling. In this framework the difference in control parameter from its value at the transition to chaos is the only relevant variable, the trivial fixed point is the Gaussian distribution and a nontrivial fixed point is a multifractal distribution with features similar to those of the Feigenbaum attractor. The crossover between the two fixed points is discussed and the flow toward the trivial fixed point is seen to consist of a sequence of chaotic band mergers.
Triple point of e-deuterium as an accurate thermometric fixed point
Pavese, F.; McConville, G.T.
1986-01-01
The triple point of deuterium (18.7/sup 0/K) is the only possibility for excluding vapor pressure measurements in the definition of a temperature scale based on fixed points between 13.81 and 24.562/sup 0/K. This paper reports an investigation made at the Istituto di Metrologia and Mound Laboratory, using extremely pure deuterium directly sealed at the production plant into small metal cells. The large contamination by HD of commercially available gas, that cannot be accounted and corrected for due to its increase in handling, was found to be very stable with time after sealing in IMGC cells. HD contamination can be limited to less than 100 ppM in Monsanto cells, both with n-D/sub 2/ and e-D/sub 2/, when filled directly from the thermal diffusion column and sealed at the factory. e-D/sub 2/ requires a special deuterated catalyst. The triple point temperature of e-D/sub 2/ has been determined to be: T(NPL-IPTS-68) = 18.7011 +- 0.002/sup 0/K. 20 refs., 3 figs., 2 tabs.
Stability of fixed points and generalized critical behavior in multifield models
NASA Astrophysics Data System (ADS)
Eichhorn, A.; Mesterházy, D.; Scherer, M. Â. M.
2014-11-01
We study models with three coupled vector fields characterized by O (N1) ⊕O (N2) ⊕O (N3) symmetry. Using the nonperturbative functional renormalization group, we derive β functions for the couplings and anomalous dimensions in d dimensions. Specializing to the case of three dimensions, we explore interacting fixed points that generalize the O (N ) Wilson-Fisher fixed point. We find a symmetry-enhanced isotropic fixed point, a large class of fixed points with partial symmetry enhancement, as well as partially and fully decoupled fixed-point solutions. We discuss their stability properties for all values of N1,N2, and N3, emphasizing important differences to the related two-field models. For small numbers of field components, we find no stable fixed-point solutions, and we argue that this can be attributed to the presence of a large class of possible (mixed) couplings in the three-field and multifield models. Furthermore, we contrast different mechanisms for stability interchange between fixed points in the case of the two- and three-field models, which generically proceed through fixed-point collisions.
Area law for fixed points of rapidly mixing dissipative quantum systems
Brandão, Fernando G. S. L.; Cubitt, Toby S.; Lucia, Angelo; Michalakis, Spyridon; Perez-Garcia, David
2015-10-15
We prove an area law with a logarithmic correction for the mutual information for fixed points of local dissipative quantum system satisfying a rapid mixing condition, under either of the following assumptions: the fixed point is pure or the system is frustration free.
Some fixed point theorems in generating space of b-quasi-metric family.
Kumari, P Sumati; Sarwar, Muhammad
2016-01-01
The purpose of this work is to study some properties of "Generating space of b-quasi-metric family"(simply [Formula: see text]-family) and derive some fixed point theorems using some standard contractions. Presented theorems extend and generalize many well-known results in the literature of fixed point theory . PMID:27006877
Code of Federal Regulations, 2012 CFR
2012-10-01
... Transmitter Control Internal Transmitter Control Systems § 90.473 Operation of internal transmitter control systems through licensed fixed control points. An internal transmitter control system may be operated... systems through licensed fixed control points. 90.473 Section 90.473 Telecommunication...
Code of Federal Regulations, 2011 CFR
2011-10-01
... Transmitter Control Internal Transmitter Control Systems § 90.473 Operation of internal transmitter control systems through licensed fixed control points. An internal transmitter control system may be operated... systems through licensed fixed control points. 90.473 Section 90.473 Telecommunication...
Code of Federal Regulations, 2013 CFR
2013-10-01
... Transmitter Control Internal Transmitter Control Systems § 90.473 Operation of internal transmitter control systems through licensed fixed control points. An internal transmitter control system may be operated... systems through licensed fixed control points. 90.473 Section 90.473 Telecommunication...
Code of Federal Regulations, 2014 CFR
2014-10-01
... Transmitter Control Internal Transmitter Control Systems § 90.473 Operation of internal transmitter control systems through licensed fixed control points. An internal transmitter control system may be operated... systems through licensed fixed control points. 90.473 Section 90.473 Telecommunication...
Code of Federal Regulations, 2010 CFR
2010-10-01
... Transmitter Control Internal Transmitter Control Systems § 90.473 Operation of internal transmitter control systems through licensed fixed control points. An internal transmitter control system may be operated... systems through licensed fixed control points. 90.473 Section 90.473 Telecommunication...
A 64-bit orthorectification algorithm using fixed-point arithmetic
NASA Astrophysics Data System (ADS)
French, Joseph C.; Balster, Eric J.; Turri, William F.
2013-10-01
As the cost of imaging systems have decreased, the quality and size has increased. This dynamic has made the practicality of many aerial imaging applications achievable such as cost line monitoring and vegetation indexing. Orthorectification is required for many of these applications; however, it is also expensive, computationally. The computational cost is due to oating point operations and divisions inherent in the orthorecti cation process. Two novel algorithm modi cations are proposed which signi cantly reduce the computational cost. The rst modi cation uses xed-point arithmetic in place of the oating point operations. The second replaces the division with a multiplication of the inverse. The result in an increase of 2x of the throughput while remaining within 15% of a pixel size in position.
A fixed point theorem for certain operator valued maps
NASA Technical Reports Server (NTRS)
Brown, D. R.; Omalley, M. J.
1978-01-01
In this paper, we develop a family of Neuberger-like results to find points z epsilon H satisfying L(z)z = z and P(z) = z. This family includes Neuberger's theorem and has the additional property that most of the sequences q sub n converge to idempotent elements of B sub 1(H).
Common fixed points in best approximation for Banach operator pairs with Ciric type I-contractions
NASA Astrophysics Data System (ADS)
Hussain, N.
2008-02-01
The common fixed point theorems, similar to those of Ciric [Lj.B. Ciric, On a common fixed point theorem of a Gregus type, Publ. Inst. Math. (Beograd) (N.S.) 49 (1991) 174-178; Lj.B. Ciric, On Diviccaro, Fisher and Sessa open questions, Arch. Math. (Brno) 29 (1993) 145-152; Lj.B. Ciric, On a generalization of Gregus fixed point theorem, Czechoslovak Math. J. 50 (2000) 449-458], Fisher and Sessa [B. Fisher, S. Sessa, On a fixed point theorem of Gregus, Internat. J. Math. Math. Sci. 9 (1986) 23-28], Jungck [G. Jungck, On a fixed point theorem of Fisher and Sessa, Internat. J. Math. Math. Sci. 13 (1990) 497-500] and Mukherjee and Verma [R.N. Mukherjee, V. Verma, A note on fixed point theorem of Gregus, Math. Japon. 33 (1988) 745-749], are proved for a Banach operator pair. As applications, common fixed point and approximation results for Banach operator pair satisfying Ciric type contractive conditions are obtained without the assumption of linearity or affinity of either T or I. Our results unify and generalize various known results to a more general class of noncommuting mappings.
Fixed point sensitivity analysis of interacting structured populations.
Barabás, György; Meszéna, Géza; Ostling, Annette
2014-03-01
Sensitivity analysis of structured populations is a useful tool in population ecology. Historically, methodological development of sensitivity analysis has focused on the sensitivity of eigenvalues in linear matrix models, and on single populations. More recently there have been extensions to the sensitivity of nonlinear models, and to communities of interacting populations. Here we derive a fully general mathematical expression for the sensitivity of equilibrium abundances in communities of interacting structured populations. Our method yields the response of an arbitrary function of the stage class abundances to perturbations of any model parameters. As a demonstration, we apply this sensitivity analysis to a two-species model of ontogenetic niche shift where each species has two stage classes, juveniles and adults. In the context of this model, we demonstrate that our theory is quite robust to violating two of its technical assumptions: the assumption that the community is at a point equilibrium and the assumption of infinitesimally small parameter perturbations. Our results on the sensitivity of a community are also interpreted in a niche theoretical context: we determine how the niche of a structured population is composed of the niches of the individual states, and how the sensitivity of the community depends on niche segregation. PMID:24368160
Existence of Tripled Fixed Points for a Class of Condensing Operators in Banach Spaces
Karakaya, Vatan; Bouzara, Nour El Houda; Doğan, Kadri; Atalan, Yunus
2014-01-01
We give some results concerning the existence of tripled fixed points for a class of condensing operators in Banach spaces. Further, as an application, we study the existence of solutions for a general system of nonlinear integral equations. PMID:25866836
NASA Astrophysics Data System (ADS)
Liu, Xuan-Zuo; Tian, Dong-Ping; Chong, Bo
2016-06-01
Liu et al. [Phys. Rev. Lett. 90(17), 170404 (2003)] proved that the characters of transition probabilities in the adiabatic limit should be entirely determined by the topology of energy levels and the stability of fixed points in the classical Hamiltonian system, according to the adiabatic theorem. In the special case of nonlinear Landau-Zener model, we simplify their results to be that the properties of transition probabilities in the adiabatic limit should just be determined by the attributes of fixed points. It is because the topology of energy levels is governed by the behavior and symmetries of fixed points, and intuitively this fact is represented as a correspondence between energy levels and evolution curves of the fixed points which can be quantitatively described as the same complexity numbers.
On synchronal algorithm for fixed point and variational inequality problems in hilbert spaces.
Bulama, L M; K?l?man, A
2016-01-01
The aim of this article is to expand and generalize some approximation methods proposed by Tian and Di (J Fixed Point Appl, 2011. doi:10.1186/1687-1812-21) to the class of [Formula: see text]-total asymptotically strict pseudocontraction to solve the fixed point problem as well as variational inequality problem in the frame work of Hilbert space. Further, the results presented in this paper extend, improve and also generalize several known results in the literature . PMID:26877901
New fixed points of the renormalisation group for two-body scattering
NASA Astrophysics Data System (ADS)
Birse, M. C.; Epelbaum, E.; Gegelia, J.
2016-02-01
We outline a separable matrix ansatz for the potentials in effective field theories of non-relativistic two-body systems with short-range interactions. We use this ansatz to construct new fixed points of the renormalisation-group equation for these potentials. New fixed points indicate a much richer structure than previously recognized in the RG flows of simple short-range potentials.
Extending the Nonlinear-Beam-Dynamics Concept of 1D Fixed Points to 2D Fixed Lines
NASA Astrophysics Data System (ADS)
Franchetti, G.; Schmidt, F.
2015-06-01
The origin of nonlinear dynamics traces back to the study of the dynamics of planets with the seminal work of Poincaré at the end of the nineteenth century: Les Méthodes Nouvelles de la Mécanique Céleste, Vols. 1-3 (Gauthier Villars, Paris, 1899). In his work he introduced a methodology fruitful for investigating the dynamical properties of complex systems, which led to the so-called "Poincaré surface of section," which allows one to capture the global dynamical properties of a system, characterized by fixed points and separatrices with respect to regular and chaotic motion. For two-dimensional phase space (one degree of freedom) this approach has been extremely useful and applied to particle accelerators for controlling their beam dynamics as of the second half of the twentieth century. We describe here an extension of the concept of 1D fixed points to fixed lines in two dimensions. These structures become the fundamental entities for characterizing the nonlinear motion in the four-dimensional phase space (two degrees of freedom).
Extending the Nonlinear-Beam-Dynamics Concept of 1D Fixed Points to 2D Fixed Lines.
Franchetti, G; Schmidt, F
2015-06-12
The origin of nonlinear dynamics traces back to the study of the dynamics of planets with the seminal work of Poincaré at the end of the nineteenth century: Les Méthodes Nouvelles de la Mécanique Céleste, Vols. 1-3 (Gauthier Villars, Paris, 1899). In his work he introduced a methodology fruitful for investigating the dynamical properties of complex systems, which led to the so-called "Poincaré surface of section," which allows one to capture the global dynamical properties of a system, characterized by fixed points and separatrices with respect to regular and chaotic motion. For two-dimensional phase space (one degree of freedom) this approach has been extremely useful and applied to particle accelerators for controlling their beam dynamics as of the second half of the twentieth century. We describe here an extension of the concept of 1D fixed points to fixed lines in two dimensions. These structures become the fundamental entities for characterizing the nonlinear motion in the four-dimensional phase space (two degrees of freedom). PMID:26196806
Analysis of fixed point FFT for Fourier domain optical coherence tomography systems.
Ali, Murtaza; Parlapalli, Renuka; Magee, David P; Dasgupta, Udayan
2009-01-01
Optical coherence tomography (OCT) is a new imaging modality gaining popularity in the medical community. Its application includes ophthalmology, gastroenterology, dermatology etc. As the use of OCT increases, the need for portable, low power devices also increases. Digital signal processors (DSP) are well suited to meet the signal processing requirements of such a system. These processors usually operate on fixed precision. This paper analyzes the issues that a system implementer faces implementing signal processing algorithms on fixed point processor. Specifically, we show the effect of different fixed point precisions in the implementation of FFT on the sensitivity of Fourier domain OCT systems. PMID:19965018
NASA Astrophysics Data System (ADS)
Fellmuth, B.; Wolber, L.; Head, D. I.; Hermier, Y.; Hill, K. D.; Nakano, T.; Pavese, F.; Peruzzi, A.; Rusby, R. L.; Shkraba, V.; Steele, A. G.; Steur, P. P. M.; Szmyrka-Grzebyk, A.; Tew, W. L.; Wang, L.; White, D. R.
2012-06-01
An overview of the results of an international star intercomparison of low-temperature fixed points is given. Between 1997 and 2005, 68 sealed triple-point cells (STPCs) of the twelve laboratories represented by the authors were investigated at PTB. The STPCs are used to realize the triple points of hydrogen, neon, oxygen and argon as defining fixed points of the International Temperature Scale of 1990, ITS-90. The melting curves (MCs) of all STPCs have been measured on the same experimental equipment, adhering strictly to a single measurement program. This protocol enables separation of the effects influencing the MCs and direct comparison of the thermal behaviour of the STPCs, which are quite different with respect to design, age, gas source and filling technology. In the paper, special emphasis is given to the spread of the liquidus-point temperatures and to the uncertainty of their determination. Connections between the star intercomparison and completed and ongoing international activities are also discussed.
NASA Astrophysics Data System (ADS)
Viesca, R. C.
2014-12-01
A fault's transition from slow creep to the propagation of an earthquake-generating dynamic rupture is thought to start as a quasi-static slip instability. Here we examine how such an instability develops on a sliding interface whose strength is governed by a slip rate- and state-dependent friction, where the state variable evolves according to the aging law. We find that the development occurs as the attraction of a dynamical system to a fixed point. The fixed points are such that the state of slip and the rate at which velocity diverges (and its spatial distribution) are known. The fixed points are independent of the manner of external forcing and the values of slip rate and state before the onset of instability. For a fault under uniform normal stress and frictional properties, the sole parameter that determines the fixed point (to within a translational invariance) is the ratio of the frictional parameters, a/b (where, for steady-state rate weakening, 0fixed points are asymptotically stable; however, stability is lost for a/b above that value. Increasing a/b above this critical value leads to a series of Hopf bifurcations. This cascade of bifurcations signals a quasi-periodic route to chaos, implying the existence of a second, larger, critical value of a/b (corresponding to the value at which the third Hopf bifurcation occurs), above which the slip instability may develop in a chaotic fashion. The fixed-point solutions, as well as the critical thresholds concerning their stability, depend on the configuration of slip (e.g., in/anti-plane or mixed-mode slip) and the elastic environment in which the interface is embedded (e.g., a slip surface between elastic half-spaces or one lying below and parallel to a free surface); solving for a fixed point reduces to the solution of an equivalent problem of an equilibrium slip-weakening fracture; and fixed-point stability is determined by linear stability analysis. Solutions of the fixed points and results concerning their stability are found either numerically or in closed form. For comparison, we find numerical solutions of instability development for given initial conditions and forcing. The resulting behaviors of the dynamical system conform precisely to expectations set by the fixed points and the analysis of their stability.
NASA Astrophysics Data System (ADS)
Konvalinka, Ira; Quddus, Azhar; Asraf, Daniel
2009-05-01
Today there is no direct path for the conversion of a floating-point algorithm implementation to an optimized fixed-point implementation. This paper proposes a novel and efficient methodology for Floating-point to Fixed-point Conversion (FFC) of biometric Fingerprint Algorithm Library (FAL) on fixed-point DaVinci processor. A general FFC research task is streamlined along smaller tasks which can be accomplished with lower effort and higher certainty. Formally specified in this paper is the optimization target in FFC, to preserve floating-point accuracy and to reduce execution time, while preserving the majority of algorithm code base. A comprehensive eight point strategy is formulated to achieve that target. Both local (focused on the most time consuming routines) and global optimization flow (to optimize across multiple routines) are used. Characteristic phases in the FFC activity are presented using data from employing the proposed FFC methodology to FAL, starting with target optimization specification, to speed optimization breakthroughs, finalized with validation of FAL accuracy after the execution time optimization. FAL implementation resulted in biometric verification time reduction for over a factor of 5, with negligible impact on accuracy. Any algorithm developer facing the task of implementing his floating-point algorithm on DaVinci DSP is expected to benefit from this presentation.
A Concerted International Project to Establish High-Temperature Fixed Points for Primary Thermometry
NASA Astrophysics Data System (ADS)
Machin, G.; Bloembergen, P.; Hartmann, J.; Sadli, M.; Yamada, Y.
2007-12-01
Research into high-temperature fixed points above 1,100°C has made significant progress since they were first reported in 1999. In particular, it has been established that single cells are repeatable at the sub-50 mK level, and intra-cell reproducibility at the 100 mK level has been demonstrated even at temperatures as high as 2,500°C. The fixed points have been used to compare temperature and radiometry scales over a wide temperature range, and are being developed and established as secondary references for thermocouple calibrations. However, before they can be fully accepted as primary temperature references, much work remains to be done, namely: (1) Establishment of long-term stability of the fixed-point temperature; (2) Development of robust procedures for the reliable construction of the fixed-point cells (to ensure routine intra-cell reproducibility of 100 mK); (3) Demonstration of long-term robustness of the fixed-point cells; (4) Assignment of thermodynamic temperatures to a selected set of fixed points; (5) Agreement and acceptance of these temperature values by the CCT; (6) Agreed methods on how to take full utility of these new fixed points into any future International Temperature Scale (ITS)—or the current ITS-90 via an addendum to the mise en pratique for the definition of the kelvin. To ensure that this work progresses to completion in a reasonable time frame, a research project, under the auspices of the CCT-WG5, has been formulated and is currently in progress with the aim of achieving the above mentioned targets by 2012. This article will describe this project and detail partner contributions.
Noether identities and gauge fixing the action for cosmological perturbations
NASA Astrophysics Data System (ADS)
Lagos, Macarena; Bañados, Máximo; Ferreira, Pedro G.; García-Sáenz, Sebastián
2014-01-01
We propose and develop a general algorithm for finding the action for cosmological perturbations which rivals the conventional, gauge-invariant approach and can be applied to theories with more than one metric. We then apply it to a particular case of bigravity, focusing on the Eddington-inspired Born-Infeld theory, and show that we can obtain a nearly scale-invariant power spectrum for both scalar and tensor primordial quantum perturbations. Unfortunately, in the case of the minimal Eddington-inspired Born-Infeld theory, we find that the tensor-to-scalar ratio of perturbations is unacceptably large. We discuss the applicability of our general method and the possibility of resurrecting the specific theory we have looked at.
Dark energy as a fixed point of the Einstein Yang-Mills Higgs equations
NASA Astrophysics Data System (ADS)
Rinaldi, Massimiliano
2015-10-01
We study the Einstein Yang-Mills Higgs equations in the SO(3) representation on a isotropic and homogeneous flat Universe, in the presence of radiation and matter fluids. We map the equations of motion into an autonomous dynamical system of first-order differential equations and we find the equilibrium points. We show that there is only one stable fixed point that corresponds to an accelerated expanding Universe in the future. In the past, instead, there is an unstable fixed point that implies a stiff-matter domination. In between, we find three other unstable fixed points, corresponding, in chronological order, to radiation domination, to matter domination, and, finally, to a transition from decelerated expansion to accelerated expansion. We solve the system numerically and we confirm that there are smooth trajectories that correctly describe the evolution of the Universe, from a remote past dominated by radiation to a remote future dominated by dark energy, passing through a matter-dominated phase.
Triple-Fixed-Point Blackbody for the Calibration of Radiation Thermometers
NASA Astrophysics Data System (ADS)
Schalles, Marc; Bernhard, F.
2007-12-01
A new triple-fixed-point blackbody containing the fixed-point materials aluminum (freezing point 660.323°C), zinc (FP 419.527°C), and tin (FP 231.928°C) in one device has been developed at the Ilmenau University of Technology. It enables calibration of a radiation thermometer with direct reference to the ITS-90 at three fixed points after a single adjustment of the calibration object. The setup significantly reduces the technical effort and the time for the calibration procedure. Measurements of the phase-transition temperature and the time-dependent blackbody temperature made with a transfer radiation thermometer, the Linearpyrometer LP5 of the IKE Stuttgart, are presented in the article.
Fixed-point bifurcation analysis in biological models using interval polynomials theory.
Rigatos, Gerasimos G
2014-06-01
The paper proposes a systematic method for fixed-point bifurcation analysis in circadian cells and similar biological models using interval polynomials theory. The stages for performing fixed-point bifurcation analysis in such biological systems comprise (i) the computation of fixed points as functions of the bifurcation parameter and (ii) the evaluation of the type of stability for each fixed point through the computation of the eigenvalues of the Jacobian matrix that is associated with the system's nonlinear dynamics model. Stage (ii) requires the computation of the roots of the characteristic polynomial of the Jacobian matrix. This problem is nontrivial since the coefficients of the characteristic polynomial are functions of the bifurcation parameter and the latter varies within intervals. To obtain a clear view about the values of the roots of the characteristic polynomial and about the stability features they provide to the system, the use of interval polynomials theory and particularly of Kharitonov's stability theorem is proposed. In this approach, the study of the stability of a characteristic polynomial with coefficients that vary in intervals is equivalent to the study of the stability of four polynomials with crisp coefficients computed from the boundaries of the aforementioned intervals. The efficiency of the proposed approach for the analysis of fixed-point bifurcations in nonlinear models of biological neurons is tested through numerical and simulation experiments. PMID:24817437
Fixed-point theorems for families of weakly non-expansive maps
NASA Astrophysics Data System (ADS)
Mai, Jie-Hua; Liu, Xin-He
2007-10-01
In this paper, we present some fixed-point theorems for families of weakly non-expansive maps under some relatively weaker and more general conditions. Our results generalize and improve several results due to Jungck [G. Jungck, Fixed points via a generalized local commutativity, Int. J. Math. Math. Sci. 25 (8) (2001) 497-507], Jachymski [J. Jachymski, A generalization of the theorem by Rhoades and Watson for contractive type mappings, Math. Japon. 38 (6) (1993) 1095-1102], Guo [C. Guo, An extension of fixed point theorem of Krasnoselski, Chinese J. Math. (P.O.C.) 21 (1) (1993) 13-20], Rhoades [B.E. Rhoades, A comparison of various definitions of contractive mappings, Trans. Amer. Math. Soc. 226 (1977) 257-290], and others.
Infrared fixed point solution for the top quark mass and unification of couplings in the MSSM
Bardeen, W.A.; Carena, M.; Pokorski, S.; Wagner, C.E.M.
1993-08-01
We analyze the implications of the infrared quasi fixed point solution for the top quark mass in the Minimal Supersymmetric Standard Model. This solution could explain in a natural way the relatively large value of the top quark mass and, if confirmed experimentally, may be suggestive of the onset of nonperturbative physics at very high energy scales. In the framework of grand unification, the expected bottom quark -- tau lepton Yukawa coupling unification is very sensitive to the fixed point structure of the top quark mass. For the presently allowed values of the electroweak parameters and the bottom quark mass, the Yukawa coupling unification implies that the top quark mass must be within ten percent of its fixed point values.
Discovering and quantifying nontrivial fixed points in multi-field models
NASA Astrophysics Data System (ADS)
Eichhorn, A.; Helfer, T.; Mesterházy, D.; Scherer, M. M.
2016-02-01
We use the functional renormalization group and the ɛ -expansion concertedly to explore multicritical universality classes for coupled bigoplus _i O(N_i) vector-field models in three Euclidean dimensions. Exploiting the complementary strengths of these two methods we show how to make progress in theories with large numbers of interactions, and a large number of possible symmetry-breaking patterns. For the three- and four-field models we find a new fixed point that arises from the mutual interaction between different field sectors, and we establish the absence of infrared-stable fixed-point solutions for the regime of small N_i. Moreover, we explore these systems as toy models for theories that are both asymptotically safe and infrared complete. In particular, we show that these models exhibit complete renormalization group trajectories that begin and end at nontrivial fixed points.
Miniature Fixed-Point Cell Approaches for Monitoring of Thermocouple Stability
NASA Astrophysics Data System (ADS)
Failleau, G.; Elliott, C. J.; Deuz, T.; Pearce, J. V.; Machin, G.; Sadli, M.
2014-07-01
In the framework of the European Metrology Research Project ENG08 "MetroFission," LNE-Cnam and NPL have undertaken cooperative research into the development of temperature measurement solutions for the next generation of nuclear fission power plants. Currently, in-pile temperature monitoring is usually performed with nickel-based (Type K or N) thermocouples. When these thermocouples are exposed to a neutron flux, the thermoelements transmute, leading to large and unknown drifts in output. In addition, it is impossible to routinely recalibrate the thermocouples after irradiation for obvious reasons of safety. To alleviate this problem, both LNE-Cnam and NPL have developed, via differing approaches, in situ calibration methods for the thermocouples. The self-validating thermocouple methodologies are based on the principle of a miniature fixed-point cell to be co-located with the thermocouple measurement junction in use. The drift of the thermocouple can be monitored and corrected for by regular determination of the output at the phase transition of the fixed-point material: in effect performing regular in situ calibration checks. The two institutes have constructed miniature fixed-point cells for use at three different temperatures; the freezing point of silver ; LNE-Cnam), the freezing point of copper ; LNE-Cnam and NPL), and the melting point of Fe-C (; NPL). This paper introduces the construction and validation of the miniature fixed-point cells prior to use, to ensure traceability to the ITS-90. A comparison of the performance of the two cell designs is discussed, where typical industrial Type N thermocouples have been used for measurement of the fixed-point cells. Such initial measurements demonstrate the feasibility of each of these two approaches.
Parallel Fixed Point Implementation of a Radial Basis Function Network in an FPGA
de Souza, Alisson C. D.; Fernandes, Marcelo A. C.
2014-01-01
This paper proposes a parallel fixed point radial basis function (RBF) artificial neural network (ANN), implemented in a field programmable gate array (FPGA) trained online with a least mean square (LMS) algorithm. The processing time and occupied area were analyzed for various fixed point formats. The problems of precision of the ANN response for nonlinear classification using the XOR gate and interpolation using the sine function were also analyzed in a hardware implementation. The entire project was developed using the System Generator platform (Xilinx), with a Virtex-6 xc6vcx240t-1ff1156 as the target FPGA. PMID:25268918
Parallel fixed point implementation of a radial basis function network in an FPGA.
de Souza, Alisson C D; Fernandes, Marcelo A C
2014-01-01
This paper proposes a parallel fixed point radial basis function (RBF) artificial neural network (ANN), implemented in a field programmable gate array (FPGA) trained online with a least mean square (LMS) algorithm. The processing time and occupied area were analyzed for various fixed point formats. The problems of precision of the ANN response for nonlinear classification using the XOR gate and interpolation using the sine function were also analyzed in a hardware implementation. The entire project was developed using the System Generator platform (Xilinx), with a Virtex-6 xc6vcx240t-1ff1156 as the target FPGA. PMID:25268918
Fixed point results for G-α-contractive maps with application to boundary value problems.
Hussain, Nawab; Parvaneh, Vahid; Roshan, Jamal Rezaei
2014-01-01
We unify the concepts of G-metric, metric-like, and b-metric to define new notion of generalized b-metric-like space and discuss its topological and structural properties. In addition, certain fixed point theorems for two classes of G-α -admissible contractive mappings in such spaces are obtained and some new fixed point results are derived in corresponding partially ordered space. Moreover, some examples and an application to the existence of a solution for the first-order periodic boundary value problem are provided here to illustrate the usability of the obtained results. PMID:24895655
One loop beta functions and fixed points in higher derivative sigma models
Percacci, Roberto; Zanusso, Omar
2010-03-15
We calculate the one loop beta functions of nonlinear sigma models in four dimensions containing general two- and four-derivative terms. In the O(N) model there are four such terms and nontrivial fixed points exist for all N{>=}4. In the chiral SU(N) models there are in general six couplings, but only five for N=3 and four for N=2; we find fixed points only for N=2, 3. In the approximation considered, the four-derivative couplings are asymptotically free but the coupling in the two-derivative term has a nonzero limit. These results support the hypothesis that certain sigma models may be asymptotically safe.
On a sharpened form of the Schauder fixed-point theorem.
Browder, F E
1977-11-01
If K is a compact convex subset of a locally convex topological vector space X, we consider a continuous mapping f of K into X. A fixed-point theorem is proved for such a map f under the assumption that for a given continuous realvalued function p on K x X with p(x,y) convex in y and for each point x in K not fixed by f, there exists a point y in the inward set I(K)(x) generated by K at x with p(x,y - f(x)) less than p(x,x - f(x)). For X a Banach space, in particular, this yields a sharp extension and a drastic simplification of the fixed point theory of weakly inward (and weakly outward) mappings. The result comes close in the domain of mappings of compact convex sets to the thrust of fixed point conditions of the Leray-Schauder type for compact maps of sets with interior in X. PMID:16592465
NASA Astrophysics Data System (ADS)
Katzav, Eytan
2013-04-01
In this paper, a mode of using the Dynamic Renormalization Group (DRG) method is suggested in order to cope with inconsistent results obtained when applying it to a continuous family of one-dimensional nonlocal models. The key observation is that the correct fixed-point dynamical system has to be identified during the analysis in order to account for all the relevant terms that are generated under renormalization. This is well established for static problems, however poorly implemented in dynamical ones. An application of this approach to a nonlocal extension of the Kardar-Parisi-Zhang equation resolves certain problems in one-dimension. Namely, obviously problematic predictions are eliminated and the existing exact analytic results are recovered.
Fixed-point distributions of short-range Ising spin glasses on hierarchical lattices.
Almeida, Sebastião T O; Nobre, Fernando D
2015-03-01
Fixed-point distributions for the couplings of Ising spin glasses with nearest-neighbor interactions on hierarchical lattices are investigated numerically. Hierarchical lattices within the Migdal-Kadanoff family with fractal dimensions in the range 2.58≤D≤7, as well as a lattice of the Wheatstone-Bridge family with fractal dimension D≈3.58 are considered. Three initial distributions for the couplings are analyzed, namely, the Gaussian, bimodal, and uniform ones. In all cases, after a few iterations of the renormalization-group procedure, the associated probability distributions approached universal fixed shapes. For hierarchical lattices of the Migdal-Kadanoff family, the fixed-point distributions were well fitted either by stretched exponentials, or by q-Gaussian distributions; both fittings recover the expected Gaussian limit as D→∞. In the case of the Wheatstone-Bridge lattice, the best fit was found by means of a stretched-exponential distribution. PMID:25871085
Fixed-point distributions of short-range Ising spin glasses on hierarchical lattices
NASA Astrophysics Data System (ADS)
Almeida, Sebastião T. O.; Nobre, Fernando D.
2015-03-01
Fixed-point distributions for the couplings of Ising spin glasses with nearest-neighbor interactions on hierarchical lattices are investigated numerically. Hierarchical lattices within the Migdal-Kadanoff family with fractal dimensions in the range 2.58 ≤D ≤7 , as well as a lattice of the Wheatstone-Bridge family with fractal dimension D ≈3.58 are considered. Three initial distributions for the couplings are analyzed, namely, the Gaussian, bimodal, and uniform ones. In all cases, after a few iterations of the renormalization-group procedure, the associated probability distributions approached universal fixed shapes. For hierarchical lattices of the Migdal-Kadanoff family, the fixed-point distributions were well fitted either by stretched exponentials, or by q -Gaussian distributions; both fittings recover the expected Gaussian limit as D →∞ . In the case of the Wheatstone-Bridge lattice, the best fit was found by means of a stretched-exponential distribution.
Combined GPS/GLONASS Precise Point Positioning with Fixed GPS Ambiguities
Pan, Lin; Cai, Changsheng; Santerre, Rock; Zhu, Jianjun
2014-01-01
Precise point positioning (PPP) technology is mostly implemented with an ambiguity-float solution. Its performance may be further improved by performing ambiguity-fixed resolution. Currently, the PPP integer ambiguity resolutions (IARs) are mainly based on GPS-only measurements. The integration of GPS and GLONASS can speed up the convergence and increase the accuracy of float ambiguity estimates, which contributes to enhancing the success rate and reliability of fixing ambiguities. This paper presents an approach of combined GPS/GLONASS PPP with fixed GPS ambiguities (GGPPP-FGA) in which GPS ambiguities are fixed into integers, while all GLONASS ambiguities are kept as float values. An improved minimum constellation method (MCM) is proposed to enhance the efficiency of GPS ambiguity fixing. Datasets from 20 globally distributed stations on two consecutive days are employed to investigate the performance of the GGPPP-FGA, including the positioning accuracy, convergence time and the time to first fix (TTFF). All datasets are processed for a time span of three hours in three scenarios, i.e., the GPS ambiguity-float solution, the GPS ambiguity-fixed resolution and the GGPPP-FGA resolution. The results indicate that the performance of the GPS ambiguity-fixed resolutions is significantly better than that of the GPS ambiguity-float solutions. In addition, the GGPPP-FGA improves the positioning accuracy by 38%, 25% and 44% and reduces the convergence time by 36%, 36% and 29% in the east, north and up coordinate components over the GPS-only ambiguity-fixed resolutions, respectively. Moreover, the TTFF is reduced by 27% after adding GLONASS observations. Wilcoxon rank sum tests and chi-square two-sample tests are made to examine the significance of the improvement on the positioning accuracy, convergence time and TTFF. PMID:25237901
A Common Fixed Point Theorem in Two Complete L-Fuzzy Metric Spaces
NASA Astrophysics Data System (ADS)
Sedghi, Shaban; Ghayekhloo, Somayeh; Salimi, Solaleh
2010-11-01
In this paper we first explain the concept L-fuzzy metric spaces and in this sequel explain the nation of Cauchy sequence and convergent in L-fuzzy metric spaces and finally we prove a common fixed point theorem in two complete L-fuzzy metric space.
APMP Scale Comparison with Three Radiation Thermometers and Six Fixed-Point Blackbodies
NASA Astrophysics Data System (ADS)
Yamada, Y.; Shimizu, Y.; Ishii, J.
2015-08-01
New Asia Pacific Metrology Programme (APMP) comparisons of radiation thermometry standards, APMP TS-11, and -12, have recently been initiated. These new APMP comparisons cover the temperature range from to . Three radiation thermometers with central wavelengths of 1.6 , 0.9 , and 0.65 are the transfer devices for the radiation thermometer scale comparison conducted in the so-called star configuration. In parallel, a compact fixed-point blackbody furnace that houses six types of fixed-point cells of In, Sn, Zn, Al, Ag, and Cu is circulated, again in a star-type comparison, to substantiate fixed-point calibration capabilities. Twelve APMP national metrology institutes are taking part in this endeavor, in which the National Metrology Institute of Japan acts as the pilot. In this article, the comparison scheme is described with emphasis on the features of the transfer devices, i.e., the radiation thermometers and the fixed-point blackbodies. Results of preliminary evaluations of the performance and characteristic of these instruments as well as the evaluation method of the comparison results are presented.
Fixed point results of T-Kannan contraction on generalized distance in cone metric spaces
NASA Astrophysics Data System (ADS)
Fadail, Zaid Mohammed; Ahmad, Abd Ghafur Bin
2014-06-01
In this paper, we prove the existence and uniqueness of the fixed point in some type of mappings which satisfy the T-Kannan contraction on generalized distance in cone metric spaces. The presented theorem extend and generalize several well-known comparable results in literature.
Long-Term Stability of WC-C Peritectic Fixed Point
NASA Astrophysics Data System (ADS)
Khlevnoy, B. B.; Grigoryeva, I. A.
2015-03-01
The tungsten carbide-carbon peritectic (WC-C) melting transition is an attractive high-temperature fixed point with a temperature of . Earlier investigations showed high repeatability, small melting range, low sensitivity to impurities, and robustness of WC-C that makes it a prospective candidate for the highest fixed point of the temperature scale. This paper presents further study of the fixed point, namely the investigation of the long-term stability of the WC-C melting temperature. For this purpose, a new WC-C cell of the blackbody type was built using tungsten powder of 99.999 % purity. The stability of the cell was investigated during the cell aging for 50 h at the cell working temperature that tooks 140 melting/freezing cycles. The method of investigation was based on the comparison of the WC-C tested cell with a reference Re-C fixed-point cell that reduces an influence of the probable instability of a radiation thermometer. It was shown that after the aging period, the deviation of the WC-C cell melting temperature was with an uncertainty of.
Intermediate fixed point in a Luttinger liquid with elastic and dissipative backscattering
NASA Astrophysics Data System (ADS)
Altland, Alexander; Gefen, Yuval; Rosenow, Bernd
2015-08-01
In a recent work [A. Altland, Y. Gefen, and B. Rosenow, Phys. Rev. Lett. 108, 136401 (2012), 10.1103/PhysRevLett.108.136401], we have addressed the problem of a Luttinger liquid with a scatterer that allows for both coherent and incoherent scattering channels. We have found that the physics associated with this model is qualitatively different from the elastic impurity setup analyzed by Kane and Fisher, and from the inelastic scattering scenario studied by Furusaki and Matveev, thus proposing a paradigmatic picture of Luttinger liquid with an impurity. Here we present an extensive study of the renormalization group flows for this problem, the fixed point landscape, and scaling near those fixed points. Our analysis is nonperturbative in the elastic tunneling amplitudes, employing an instanton calculation in one or two of the available elastic tunneling channels. Our analysis accounts for nontrivial Klein factors, which represent anyonic or fermionic statistics. These Klein factors need to be taken into account due to the fact that higher-order tunneling processes take place. In particular, we find a stable fixed point, where an incoming current is split 1/2 -1/2 between a forward and a backward scattered beams. This intermediate fixed point, between complete backscattering and full forward scattering, is stable for the Luttinger parameter g <1 .
Reference in Action: Links between Pointing and Language
ERIC Educational Resources Information Center
Cooperrider, Kensy Andrew
2011-01-01
When referring to things in the world, speakers produce utterances that are composites of speech and action. Pointing gestures are a pervasive part of such composite utterances, but many questions remain about exactly how pointing is integrated with speech. In this dissertation I present three strands of research that investigate relations of
Reference in Action: Links between Pointing and Language
ERIC Educational Resources Information Center
Cooperrider, Kensy Andrew
2011-01-01
When referring to things in the world, speakers produce utterances that are composites of speech and action. Pointing gestures are a pervasive part of such composite utterances, but many questions remain about exactly how pointing is integrated with speech. In this dissertation I present three strands of research that investigate relations of…
NASA Astrophysics Data System (ADS)
Bojkovski, J.; Veliki, T.; Zvizdić, D.; Drnovšek, J.
2011-08-01
The objective of project EURAMET 1127 (Bilateral comparison of triple point of mercury and melting point of gallium) in the field of thermometry is to compare realization of a triple point of mercury (-38.8344 °C) and melting point of gallium (29.7646 °C) between the Slovenian national laboratory MIRS/UL-FE/LMK and the Croatian national laboratory HMI/FSB-LPM using a long-stem 25 Ω standard platinum resistance thermometer (SPRT). MIRS/UL/FE-LMK participated in a number of intercomparisons on the level of EURAMET. On the other hand, the HMI/LPM-FSB laboratory recently acquired new fixed-point cells which had to be evaluated in the process of intercomparisons. A quartz-sheathed SPRT has been selected and calibrated at HMI/LPM-FSB at the triple point of mercury, the melting point of gallium, and the water triple point. A second set of measurements was made at MIRS/UL/FE-LMK. After its return, the SPRT was again recalibrated at HMI/LPM-FSB. In the comparison, the W value of the SPRT has been used. Results of the bilateral intercomparison confirmed that the new gallium cell of the HMI/LPM-FSB has a value that is within uncertainty limits of both laboratories that participated in the exercise, while the mercury cell experienced problems. After further research, a small leakage in the mercury fixed-point cell has been found.
Searching for fixed point combinators by using automated theorem proving: A preliminary report
Wos, L.; McCune, W.
1988-09-01
In this report, we establish that the use of an automated theorem- proving program to study deep questions from mathematics and logic is indeed an excellent move. Among such problems, we focus mainly on that concerning the construction of fixed point combinators---a problem considered by logicians to be significant and difficult to solve, and often computationally intensive and arduous. To be a fixed point combinator, THETA must satisfy the equation THETAx = x(THETAx) for all combinators x. The specific questions on which we focus most heavily ask, for each chosen set of combinators, whether a fixed point combinator can be constructed from the members of that set. For answering questions of this type, we present a new, sound, and efficient method, called the kernel method, which can be applied quite easily by hand and very easily by an automated theorem-proving program. For the application of the kernel method by a theorem-proving program, we illustrate the vital role that is played by both paramodulation and demodulation---two of the powerful features frequently offered by an automated theorem-proving program for treating equality as if it is ''understood.'' We also state a conjecture that, if proved, establishes the completeness of the kernel method. From what we can ascertain, this method---which relies on the introduced concepts of kernel and superkernel---offers the first systematic approach for searching for fixed point combinators. We successfully apply the new kernel method to various sets of combinators and, for the set consisting of the combinators B and W, construct an infinite set of fixed point combinators such that no two of the combinators are equal even in the presence of extensionality---a law that asserts that two combinators are equal if they behave the same. 18 refs.
Device-independent test of causal order and relations to fixed-points
NASA Astrophysics Data System (ADS)
Baumeler, Ämin; Wolf, Stefan
2016-03-01
Bell non-local correlations cannot be naturally explained in a fixed causal structure. This serves as a motivation for considering models where no global assumption is made beyond logical consistency. The assumption of a fixed causal order between a set of parties, together with free randomness, implies device-independent inequalities—just as the assumption of locality does. It is known that local validity of quantum theory is consistent with violating such inequalities. Moreover, for three parties or more, even the (stronger) assumption of local classical probability theory plus logical consistency allows for violating causal inequalities. Here, we show that a classical environment (with which the parties interact), possibly containing loops, is logically consistent if and only if whatever the involved parties do, there is exactly one fixed-point, the latter being representable as a mixture of deterministic fixed-points. We further show that the non-causal view allows for a model of computation strictly more powerful than computation in a world of fixed causal orders.
NASA Astrophysics Data System (ADS)
Yamada, Y.; Anhalt, K.; Battuello, M.; Bloembergen, P.; Khlevnoy, B.; Machin, G.; Matveyev, M.; Sadli, M.; Todd, A.; Wang, T.
2015-08-01
A multi-partner project to determine the thermodynamic temperatures of a selected set of high-temperature fixed points based on metal-carbon eutectics is underway as a working group activity within the Comité International des Poids et Mesures. The investigation focuses on four fixed-point types, namely, the three metal-carbon eutectic points of Re-C , Pt-C , and Co-C , and the Cu point . This paper describes the construction, pre-evaluation, and screening stage of the cells prior to their thermodynamic temperature determinations. The construction of the HTFP cells was undertaken by nine national metrology institutes (NMIs) according to instructions laid out in a pre-agreed protocol that ensures production of best quality cells. Four NMIs conducted the evaluation, each for a certain fixed-point type, and screened out cells that did not meet pre-determined selection criteria while assuring sufficient variety in the sources of the cells in the final selected sets. In autumn 2012, the selected cells were successfully passed on to the final stage of the project, the thermodynamic temperature measurement, and assignment.
A Fixed-Point Phase Lock Loop in a Software Defined Radio
NASA Astrophysics Data System (ADS)
Johannes, Michael T.
2002-09-01
A software defined radio is a much more flexible platform than traditional, hardware implemented radios, By implementing radio functions in software, and putting those functions on a Field Programmable Gate Array (FPGA) chip, users will have the ability to download mission specific radio capabilities. This thesis examines a fundamental piece of the receiver, the Phase-Lock Loop (PLL), simulates a software PLL, and investigates the effects of fixed-point versus floating point mathematics required for an FPGA based PLL. With a fixed-point PLL simulator, figures of merit such as lock-time, lock range, and pull-in range are determined% for typical signal-to-noise ratio (SNR) levels.
Tympanic thermometer performance validation by use of a body-temperature fixed point blackbody
NASA Astrophysics Data System (ADS)
Machin, Graham; Simpson, Robert
2003-04-01
The use of infrared tympanic thermometers within the medical community (and more generically in the public domain) has recently grown rapidly, displacing more traditional forms of thermometry such as mercury-in-glass. Besides the obvious health concerns over mercury the increase in the use of tympanic thermometers is related to a number of factors such as their speed and relatively non-invasive method of operation. The calibration and testing of such devices is covered by a number of international standards (ASTM1, prEN2, JIS3) which specify the design of calibration blackbodies. However these calibration sources are impractical for day-to-day in-situ validation purposes. In addition several studies (e.g. Modell et al4, Craig et al5) have thrown doubt on the accuracy of tympanic thermometers in clinical use. With this in mind the NPL is developing a practical, portable and robust primary reference fixed point source for tympanic thermometer validation. The aim of this simple device is to give the clinician a rapid way of validating the performance of their tympanic thermometer, enabling the detection of mal-functioning thermometers and giving confidence in the measurement to the clinician (and patient!) at point of use. The reference fixed point operates at a temperature of 36.3 °C (97.3 °F) with a repeatability of approximately +/- 20 mK. The fixed-point design has taken into consideration the optical characteristics of tympanic thermometers enabling wide-angled field of view devices to be successfully tested. The overall uncertainty of the device is estimated to be is less than 0.1°C. The paper gives a description of the fixed point, its design and construction as well as the results to date of validation tests.
Fixed-Point Quantum Search with an Optimal Number of Queries
NASA Astrophysics Data System (ADS)
Yoder, Theodore J.; Low, Guang Hao; Chuang, Isaac L.
2014-11-01
Grover's quantum search and its generalization, quantum amplitude amplification, provide a quadratic advantage over classical algorithms for a diverse set of tasks but are tricky to use without knowing beforehand what fraction λ of the initial state is comprised of the target states. In contrast, fixed-point search algorithms need only a reliable lower bound on this fraction but, as a consequence, lose the very quadratic advantage that makes Grover's algorithm so appealing. Here we provide the first version of amplitude amplification that achieves fixed-point behavior without sacrificing the quantum speedup. Our result incorporates an adjustable bound on the failure probability and, for a given number of oracle queries, guarantees that this bound is satisfied over the broadest possible range of λ .
Fixed-point quantum search with an optimal number of queries.
Yoder, Theodore J; Low, Guang Hao; Chuang, Isaac L
2014-11-21
Grover's quantum search and its generalization, quantum amplitude amplification, provide a quadratic advantage over classical algorithms for a diverse set of tasks but are tricky to use without knowing beforehand what fraction λ of the initial state is comprised of the target states. In contrast, fixed-point search algorithms need only a reliable lower bound on this fraction but, as a consequence, lose the very quadratic advantage that makes Grover's algorithm so appealing. Here we provide the first version of amplitude amplification that achieves fixed-point behavior without sacrificing the quantum speedup. Our result incorporates an adjustable bound on the failure probability and, for a given number of oracle queries, guarantees that this bound is satisfied over the broadest possible range of λ. PMID:25479481
Strong Convergence Algorithm for Split Equilibrium Problems and Hierarchical Fixed Point Problems
Bnouhachem, Abdellah
2014-01-01
The purpose of this paper is to investigate the problem of finding the approximate element of the common set of solutions of a split equilibrium problem and a hierarchical fixed point problem in a real Hilbert space. We establish the strong convergence of the proposed method under some mild conditions. Several special cases are also discussed. Our main result extends and improves some well-known results in the literature. PMID:24701164
The algebraic multigrid projection for eigenvalue problems; backrotations and multigrid fixed points
NASA Technical Reports Server (NTRS)
Costiner, Sorin; Taasan, Shlomo
1994-01-01
The periods of the theorem for the algebraic multigrid projection (MGP) for eigenvalue problems, and of the multigrid fixed point theorem for multigrid cycles combining MGP with backrotations, are presented. The MGP and the backrotations are central eigenvector separation techniques for multigrid eigenvalue algorithms. They allow computation on coarse levels of eigenvalues of a given eigenvalue problem, and are efficient tools in the computation of eigenvectors.
Long-Term Monitoring of Thermocouple Stability with Miniature Fixed-Point Cells
NASA Astrophysics Data System (ADS)
Elliott, C. J.; Failleau, G.; Deuzé, T.; Sadli, M.; Pearce, J. V.; Machin, G.
2014-04-01
In the framework of the European Metrology Research Programme ENG08 "MetroFission" project, two National Measurement Institutes, LNE-Cnam (France) and NPL (UK), have cooperatively developed methods of in situ validation of thermocouple output for application in next-generation nuclear fission power plants. Miniature fixed-point cells for use at three temperatures were constructed in the first step of this project: at the freezing point of silver (), the freezing point of copper (), and the melting point of the iron-carbon eutectic (). This paper reports the results of a second step in the study, where the robustness of the self-validation method has been investigated. Typical industrial Type N thermocouples have been employed with each of the miniature fixed-point devices installed, and repeatedly thermally cycled through the melting and freezing transitions of the fixed-point ingots. The devices have been exposed to a total of up to 90 h in the molten state. Furthermore, the LNE-Cnam devices were also subjected to fast cool-down rates, on five occasions, where the rate is estimated to have been between and . The devices are shown to be repeatable, reliable, and robust over the course of these tests. The drift of the Type N thermocouple has been identified separately to the behavior of the device. A reliable method for improving thermocouple performance and process control is therefore demonstrated. Requirements for implementation and the advantages of each approach for monitoring and correcting thermocouple drift are discussed, and an uncertainty budget for self-validation is presented.
Study on the Impurity Effect in the Realization of Silver Fixed Point
NASA Astrophysics Data System (ADS)
Tsai, S. F.
2016-03-01
The application of a thermal analysis model to estimate the temperature depression from the ideal fixed-point temperature is important, especially when the chemical analysis of the sample in a cell is insufficient or the cell might have been contaminated during fabrication. This study extends previous work, on thermal analysis with the tin point, to an investigation of the impurity dependence of the silver-point temperature. Close agreement was found between the temperature depression (-0.36 mK) inferred from the thermal analysis of the measured fixed-point plateau and the temperature depression (-0.32 mK) inferred using the sum of individual estimates (SIE) method with an impurity analysis based on glow discharge mass spectrometry. Additionally, the results of the thermal analysis manifest no significant dependence on the rate of solidification, and the scatter of observed gradients was within 0.36 mK among five plateaux with different temperature settings of the furnace. Although the results support the application of both the SIE method and thermal analysis for the silver point, further experiments with cell-to-cell comparisons linked to thermal analysis, a study of the thermometer-furnace systematic effects, the oxygen effect, and the locus of the freezing plateau should be investigated to reach a firm conclusion.
Robust Optimization of Fixed Points of Nonlinear Discrete Time Systems with Uncertain Parameters
NASA Astrophysics Data System (ADS)
Kastsian, Darya; Monnigmann, Martin
2010-01-01
This contribution extends the normal vector method for the optimization of parametrically uncertain dynamical systems to a general class of nonlinear discrete time systems. Essentially, normal vectors are used to state constraints on dynamical properties of fixed points in the optimization of discrete time dynamical systems. In a typical application of the method, a technical dynamical system is optimized with respect to an economic profit function, while the normal vector constraints are used to guarantee the stability of the optimal fixed point. We derive normal vector systems for flip, fold, and Neimark-Sacker bifurcation points, because these bifurcation points constitute the stability boundary of a large class of discrete time systems. In addition, we derive normal vector systems for a related type of critical point that can be used to ensure a user-specified disturbance rejection rate in the optimization of parametrically uncertain systems. We illustrate the method by applying it to the optimization of a discrete time supply chain model and a discretized fermentation process model.
NASA Astrophysics Data System (ADS)
del Campo, D.; García, C.
2013-09-01
The aim of this paper is to study the suitability of the common procedures used to estimate the calibration fitting curves of noble metal thermocouples, namely from the Pt/Rh family, in fixed points. The objective is to find out the best combination and the minimum number of fixed points that allows obtaining a reasonable interpolation uncertainty.
Video-Based Point Cloud Generation Using Multiple Action Cameras
NASA Astrophysics Data System (ADS)
Teo, T.
2015-05-01
Due to the development of action cameras, the use of video technology for collecting geo-spatial data becomes an important trend. The objective of this study is to compare the image-mode and video-mode of multiple action cameras for 3D point clouds generation. Frame images are acquired from discrete camera stations while videos are taken from continuous trajectories. The proposed method includes five major parts: (1) camera calibration, (2) video conversion and alignment, (3) orientation modelling, (4) dense matching, and (5) evaluation. As the action cameras usually have large FOV in wide viewing mode, camera calibration plays an important role to calibrate the effect of lens distortion before image matching. Once the camera has been calibrated, the author use these action cameras to take video in an indoor environment. The videos are further converted into multiple frame images based on the frame rates. In order to overcome the time synchronous issues in between videos from different viewpoints, an additional timer APP is used to determine the time shift factor between cameras in time alignment. A structure form motion (SfM) technique is utilized to obtain the image orientations. Then, semi-global matching (SGM) algorithm is adopted to obtain dense 3D point clouds. The preliminary results indicated that the 3D points from 4K video are similar to 12MP images, but the data acquisition performance of 4K video is more efficient than 12MP digital images.
Berges, Jürgen; Rothkopf, Alexander; Schmidt, Jonas
2008-07-25
Strongly correlated systems far from equilibrium can exhibit scaling solutions with a dynamically generated weak coupling. We show this by investigating isolated systems described by relativistic quantum field theories for initial conditions leading to nonequilibrium instabilities, such as parametric resonance or spinodal decomposition. The nonthermal fixed points prevent fast thermalization if classical-statistical fluctuations dominate over quantum fluctuations. We comment on the possible significance of these results for the heating of the early Universe after inflation and the question of fast thermalization in heavy-ion collision experiments. PMID:18764319
Uncertainty due to non-linearity in radiation thermometers calibrated by multiple fixed points
Yamaguchi, Y.; Yamada, Y.
2013-09-11
A new method to estimate the uncertainty due to non-linearity is described on the n= 3 scheme basis. The expression of uncertainty is mathematically derived applying the random walk method. The expression is simple and requires only the temperatures of the fixed points and a relative uncertainty value for each flux-doubling derived from the non-linearity measurement. We also present an example of the method, in which the uncertainty of temperature measurement by a radiation thermometer is calculated on the basis of non-linearity measurement.
Isotopic effects in the neon fixed point: uncertainty of the calibration data correction
NASA Astrophysics Data System (ADS)
Steur, Peter P. M.; Pavese, Franco; Fellmuth, Bernd; Hermier, Yves; Hill, Kenneth D.; Seog Kim, Jin; Lipinski, Leszek; Nagao, Keisuke; Nakano, Tohru; Peruzzi, Andrea; Sparasci, Fernando; Szmyrka-Grzebyk, Anna; Tamura, Osamu; Tew, Weston L.; Valkiers, Staf; van Geel, Jan
2015-02-01
The neon triple point is one of the defining fixed points of the International Temperature Scale of 1990 (ITS-90). Although recognizing that natural neon is a mixture of isotopes, the ITS-90 definition only states that the neon should be of ‘natural isotopic composition’, without any further requirements. A preliminary study in 2005 indicated that most of the observed variability in the realized neon triple point temperatures within a range of about 0.5 mK can be attributed to the variability in isotopic composition among different samples of ‘natural’ neon. Based on the results of an International Project (EUROMET Project No. 770), the Consultative Committee for Thermometry decided to improve the realization of the neon fixed point by assigning the ITS-90 temperature value 24.5561 K to neon with the isotopic composition recommended by IUPAC, accompanied by a quadratic equation to take the deviations from the reference composition into account. In this paper, the uncertainties of the equation are discussed and an uncertainty budget is presented. The resulting standard uncertainty due to the isotopic effect (k = 1) after correction of the calibration data is reduced to (4 to 40) μK when using neon of ‘natural’ isotopic composition or to 30 μK when using 20Ne. For comparison, an uncertainty component of 0.15 mK should be included in the uncertainty budget for the neon triple point if the isotopic composition is unknown, i.e. whenever the correction cannot be applied.
Finiteness of fixed equilibrium configurations of point vortices in the plane with a background flow
NASA Astrophysics Data System (ADS)
Cheung, Pak-Leong; Ng, Tuen Wai
2014-10-01
For a dynamic system consisting of n point vortices in an ideal plane fluid with a steady, incompressible and irrotational background flow, a more physically significant definition of a fixed equilibrium configuration is suggested. Under this new definition, if the complex polynomial w that determines the aforesaid background flow is non-constant, we have found an attainable generic upper bound \\frac{(m+n-1)!}{(m-1)!\\,n_1!\\cdots n_{i_0}!} for the number of fixed equilibrium configurations. Here, m = deg w, i0 is the number of species, and each ni is the number of vortices in a species. We transform the rational function system arising from fixed equilibria into a polynomial system, whose form is good enough to apply the BKK theory (named after Bernshtein (1975 Funct. Anal. Appl. 9 183-5), Khovanskii (1978 Funct. Anal. Appl. 12 38-46) and Kushnirenko (1976 Funct. Anal. Appl. 10 233-5)) to show the finiteness of its number of solutions. Having this finiteness, the required bound follows from Bézout's theorem or the BKK root count by Li and Wang (1996 Math. Comput. 65 1477-84).
New Sealed Cells for Realization of Cryogenic Fixed Points at NMIJ/AIST
NASA Astrophysics Data System (ADS)
Nakano, Tohru; Tamura, Osamu; Sakurai, Hirohisa
2003-09-01
New sealed cells have been developed at the National Metrology Institute of Japan (NMIJ), which are used for realization of the cryogenic fixed points of the International Temperature Scale of 1990. A metal O-ring made of stainless steel is introduced as a sealing device for the sealed cells. The triple point of equilibrium hydrogen (e-H2) is realized using the new sealed cells containing hydrogen and ferric oxy-hydroxide as a catalyst for the ortho-para equilibration. Double anomalous peaks on the heat capacity curves are observed at temperatures just below the triple point, but they are suppressed by reducing the amount of the catalyst. The reduction of the amount of catalyst allows one to obtain more reliable melting curves for e-H2. The triple-point temperature of e-H2 obtained by the new sealed cells is in good agreement with those reported previously in measurements of open cells by assuming that the dependence of the triple-point temperature on the deuterium content is 5.4 ?K per ppm of deuterium in hydrogen.
Non-thermal fixed points and solitons in a one-dimensional Bose gas
NASA Astrophysics Data System (ADS)
Schmidt, Maximilian; Erne, Sebastian; Nowak, Boris; Sexty, Dénes; Gasenzer, Thomas
2012-07-01
Single-particle momentum spectra for a dynamically evolving one-dimensional Bose gas are analysed in the semi-classical wave limit. Representing one of the simplest correlation functions, these provide information on a possible universal scaling behaviour. Motivated by the previously discovered connection between (quasi-) topological field configurations, strong wave turbulence and non-thermal fixed points of quantum field dynamics, soliton formation is studied with respect to the appearance of transient power-law spectra. A random-soliton model is developed for describing the spectra analytically, and the analogies and differences between the emerging power laws and those found in a field theory approach to strong wave turbulence are discussed. The results open a new perspective on solitary wave dynamics from the point of view of critical phenomena far from thermal equilibrium and the possibility of studying this dynamics by experiment without the need for detecting solitons in situ.
Development of a new radiometer for the thermodynamic measurement of high temperature fixed points
Dury, M. R.; Goodman, T. M.; Lowe, D. H.; Machin, G.; Woolliams, E. R.
2013-09-11
The National Physical Laboratory (NPL) has developed a new radiometer to measure the thermodynamic melting point temperatures of high temperature fixed points with ultra-low uncertainties. In comparison with the NPL's Absolute Radiation Thermometer (ART), the 'THermodynamic Optical Radiometer' (THOR) is more portable and compact, with a much lower size-of-source effect and improved performance in other parameters such as temperature sensitivity. It has been designed for calibration as a whole instrument via the radiance method, removing the need to calibrate the individual subcomponents, as required by ART, and thereby reducing uncertainties. In addition, the calibration approach has been improved through a new integrating sphere that has been designed to have greater uniformity.
Development of a new radiometer for the thermodynamic measurement of high temperature fixed points
NASA Astrophysics Data System (ADS)
Dury, M. R.; Goodman, T. M.; Lowe, D. H.; Machin, G.; Woolliams, E. R.
2013-09-01
The National Physical Laboratory (NPL) has developed a new radiometer to measure the thermodynamic melting point temperatures of high temperature fixed points with ultra-low uncertainties. In comparison with the NPL's Absolute Radiation Thermometer (ART), the "THermodynamic Optical Radiometer" (THOR) is more portable and compact, with a much lower size-of-source effect and improved performance in other parameters such as temperature sensitivity. It has been designed for calibration as a whole instrument via the radiance method, removing the need to calibrate the individual subcomponents, as required by ART, and thereby reducing uncertainties. In addition, the calibration approach has been improved through a new integrating sphere that has been designed to have greater uniformity.
Dipeptide Aggregation in Aqueous Solution from Fixed Point-Charge Force Fields.
Götz, Andreas W; Bucher, Denis; Lindert, Steffen; McCammon, J Andrew
2014-04-01
The description of aggregation processes with molecular dynamics simulations is a playground for testing biomolecular force fields, including a new generation of force fields that explicitly describe electronic polarization. In this work, we study a system consisting of 50 glycyl-l-alanine (Gly-Ala) dipeptides in solution with 1001 water molecules. Neutron diffraction experiments have shown that at this concentration, Gly-Ala aggregates into large clusters. However, general-purpose force fields in combination with established water models can fail to correctly describe this aggregation process, highlighting important deficiencies in how solute-solute and solute-solvent interactions are parametrized in these force fields. We found that even for the fully polarizable AMOEBA force field, the degree of association is considerably underestimated. Instead, a fixed point-charge approach based on the newly developed IPolQ scheme [Cerutti et al. J. Phys. Chem. 2013, 117, 2328] allows for the correct modeling of the dipeptide aggregation in aqueous solution. This result should stimulate interest in novel fitting schemes that aim to improve the description of the solvent polarization effect within both explicitly polarizable and fixed point-charge frameworks. PMID:24803868
Temperature determination of the Si-SiC eutectic fixed point using thermocouples
NASA Astrophysics Data System (ADS)
Suherlan; Kim, Yong-Gyoo; Joung, Wukchul; Yang, Inseok
2015-04-01
The temperature of the Si-SiC eutectic fixed point for use in thermocouple thermometry has been determined. Three Si-SiC cells were fabricated from pure silicon powder within separate graphite crucibles. Each of the three cells was cycled through 17 melt-freeze cycles and subjected to temperatures above 1400 °C for a period of approximately 73 h, and none showed any sign of mechanical failure. The melting transition was measured using three types of thermocouple: one type S, one type B, and two Pt/Pd thermocouples calibrated at the fixed points of Ag, Cu, Fe-C, Co-C, and Pd (only for type B). The transition temperature, measured using the type S and two Pt/Pd thermocouples, was (1410.0 ± 0.8) °C with k = 2. However, the measurement uncertainty using the type B thermocouple was as large as 1.5 °C (k = 2) due to the inhomogeneity of the thermocouple. The repeatability of the three Si-SiC cells was calculated to be 0.3 °C, and the extremes of the temperature measurement differed by 0.8 °C.
Use of Eutectic Fixed Points to Characterize a Spectrometer for Earth Observations
NASA Astrophysics Data System (ADS)
Salim, Saber G. R.; Fox, Nigel P.; Woolliams, Emma R.; Winkler, Rainer; Pegrum, Heather M.; Sun, Tong; Grattan, Ken T. V.
2007-12-01
A small palm-sized, reference spectrometer, mounted on a remote-controlled model helicopter is being developed and tested by the National Physical Laboratory (NPL) in conjunction with City University, London. The developed system will be used as a key element for field vicarious calibration of optical earth observation systems in the visible-near infrared (VNIR) region. The spectrometer is hand held, low weight, and uses a photodiode array. It has good stray light rejection and wide spectral coverage, allowing simultaneous measurements from 400 to 900 nm. The spectrometer is traceable to NPL’s primary standard cryogenic radiometer via a high-temperature metal-carbon eutectic fixed-point blackbody. Once the fixed-point temperature has been determined (using filter radiometry), the eutectic provides a high emissivity and high stability source of known spectral radiance over the emitted spectral range. All wavelength channels of the spectrometer can be calibrated simultaneously using the eutectic transition without the need for additional instrumentation. The spectrometer itself has been characterized for stray light performance and wavelength accuracy. Its long-term and transportation stability has been proven in an experiment that determined the “World’s Bluest Sky”—a process that involved 56 flights, covering 100,000 km in 72 days. This vicarious calibration methodology using a eutectic standard is presented alongside the preliminary results of an evaluation study of the spectrometer characteristics.
A Method to Improve the Temperature Distribution of Holder Around the Fixed-Point Cell Position
NASA Astrophysics Data System (ADS)
Lim, S. D.; Karmalawi, A. M.; Salim, S. G. R.; Soliman, M. A.; Kim, B. H.; Lee, D. H.; Yoo, Y. S.
2014-07-01
The temperature profile along the furnaces used in heating high-temperature fixed points has a crucial impact on the quality and duration of melting plateaux, accordingly the accuracy of thermodynamic temperature determination of such fixed points. This paper describes a simple, yet efficient, approach for improving the temperature uniformity along a cell holder in high-temperature blackbody (HTBB) furnaces that use pyrolytic graphite rings as heating elements. The method has been applied on the KRISS' HTBB furnace. In this work, an ideal solution for arranging the heating elements inside the furnace is presented by which the temperature gradient across the cell holder can be kept as low as possible. Numerical calculations, based on a finite element method, have been carried out to find the best possible arrangement of the rings. This has been followed by measuring the temperature gradient along an empty cell holder to validate our calculations. A temperature gradient of 100 mK has been achieved at over a length of 50 mm within a cell holder of 10 cm in length. It has also been shown that for a 20 cm long holder surrounded by rings with an arbitrary resistance profile, the temperature uniformity can be improved by adding a few "hot" rings around the cell holder.
Optimization of the thermogauge furnace for realizing high temperature fixed points
Wang, T.; Dong, W.; Liu, F.
2013-09-11
The thermogauge furnace was commonly used in many NMIs as a blackbody source for calibration of the radiation thermometer. It can also be used for realizing the high temperature fixed point(HTFP). According to our experience, when realizing HTFP we need the furnace provide relative good temperature uniformity to avoid the possible damage to the HTFP. To improve temperature uniformity in the furnace, the furnace tube was machined near the tube ends with a help of a simulation analysis by 'ansys workbench'. Temperature distributions before and after optimization were measured and compared at 1300 °C, 1700°C, 2500 °C, which roughly correspond to Co-C(1324 °C), Pt-C(1738 °C) and Re-C(2474 °C), respectively. The results clearly indicate that through machining the tube the temperature uniformity of the Thermogage furnace can be remarkably improved. A Pt-C high temperature fixed point was realized in the modified Thermogauge furnace subsequently, the plateaus were compared with what obtained using old heater, and the results were presented in this paper.
Woolliams, E R; Anhalt, K; Ballico, M; Bloembergen, P; Bourson, F; Briaudeau, S; Campos, J; Cox, M G; del Campo, D; Dong, W; Dury, M R; Gavrilov, V; Grigoryeva, I; Hernanz, M L; Jahan, F; Khlevnoy, B; Khromchenko, V; Lowe, D H; Lu, X; Machin, G; Mantilla, J M; Martin, M J; McEvoy, H C; Rougié, B; Sadli, M; Salim, S G R; Sasajima, N; Taubert, D R; Todd, A D W; Van den Bossche, R; van der Ham, E; Wang, T; Whittam, A; Wilthan, B; Woods, D J; Woodward, J T; Yamada, Y; Yamaguchi, Y; Yoon, H W; Yuan, Z
2016-03-28
The thermodynamic temperature of the point of inflection of the melting transition of Re-C, Pt-C and Co-C eutectics has been determined to be 2747.84 ± 0.35 K, 2011.43 ± 0.18 K and 1597.39 ± 0.13 K, respectively, and the thermodynamic temperature of the freezing transition of Cu has been determined to be 1357.80 ± 0.08 K, where the ± symbol represents 95% coverage. These results are the best consensus estimates obtained from measurements made using various spectroradiometric primary thermometry techniques by nine different national metrology institutes. The good agreement between the institutes suggests that spectroradiometric thermometry techniques are sufficiently mature (at least in those institutes) to allow the direct realization of thermodynamic temperature above 1234 K (rather than the use of a temperature scale) and that metal-carbon eutectics can be used as high-temperature fixed points for thermodynamic temperature dissemination. The results directly support the developing mise en pratique for the definition of the kelvin to include direct measurement of thermodynamic temperature. PMID:26903099
Adaptive array beamforming with fixed-point arithmetic matrix inversion using Givens rotations
NASA Astrophysics Data System (ADS)
Rabinkin, Daniel V.; Song, William; Vai, M. Michael; Nguyen, Huy T.
2001-11-01
Adaptive array systems require the periodic solution of the well-known w=R1v equation in order to compute optimum adaptive array weights. The covariance matrix R is estimated by forming a product of noise sample matrices X:R=XHX. The operations-count cost of performing the required matrix inversion in real time can be prohibitively high for a high bandwidth system with a large number of sensors. Specialized hardware may be required to execute the requisite computations in real time. The choice of algorithm to perform these computations must be considered in conjunction with the hardware technology used to implement the computation engine. A systolic architecture implementation of the Givens rotation method for matrix inversion was selected to perform adaptive weight computation. The bit-level systolic approach enables a simple ASIC design and a very low power implementation. The bit-level systolic architecture must be implemented with fixed-point arithmetic to simplify the propagation of data through the computation cells. The Givens rotation approach has a highly parallel implementation and is ideally suited for a systolic implementation. Additionally, the adaptive weights are computed directly from the sample matrix X in the voltage domain, thus reducing the required dynamic range needed in carrying out the computations. An analysis was performed to determine the required fixed-point precision needed to compute the weights for an adaptive array system operating in the presence of interference. Based on the analysis results, it was determined that the precision of a floating-point computation can be well approximated with a 13-bit to 19-bit word length fixed point computation for typical system jammer-to-noise levels. This property has produced an order-of-magnitude reduction in required hardware complexity. A synthesis-based ASIC design process was used to generate preliminary layouts. These layouts were used to estimate the area and throughput of the VLSI QR decomposition architecture. The results show that this QR decomposition process, when implemented into a full-custom design, provides a computation time that is two orders of magnitude faster than a state-of-the-art microprocessor.
NASA Astrophysics Data System (ADS)
Zhang, Xiaohong; Li, Pan
2013-06-01
Ambiguity resolution (AR) for a single receiver has been a popular topic in Global Positioning System (GPS) recently. Ambiguity-resolution methods for precise point positioning (PPP) have been well documented in recent years, demonstrating that it can improve the accuracy of PPP. However, users are often concerned about the reliability of ambiguity-fixed PPP solution in practical applications. If ambiguities are fixed to wrong integers, large errors would be introduced into position estimates. In this paper, we aim to assess the correct fixing rate (CFR), i.e., number of ambiguities correctly fixing to the total number of ambiguities correctly and incorrectly fixing, for PPP user ambiguity resolution on a global scale. A practical procedure is presented to evaluate the CFR of PPP user ambiguity resolution. GPS data of the first 3 days in each month of 2010 from about 390 IGS stations are used for experiments. Firstly, we use GPS data collected from about 320 IGS stations to estimate global single-differenced (SD) wide-lane and narrow-lane satellite uncalibrated phase delays (UPDs). The quality of UPDs is evaluated. We found that wide-lane UPD estimates have a rather small standard deviation (Std) between 0.003 and 0.004 cycles while most of Std of narrow-lane estimates are from 0.01 to 0.02 cycles. Secondly, many experiments have been conducted to investigate the CFR of integer ambiguity resolution we can achieve under different conditions, including reference station density, observation session length and the ionospheric activity. The results show that the CFR of PPP can exceed 98.0 % with only 1 h of observations for most user stations. No obvious correlation between the CFR and the reference station density is found. Therefore, nearly homogeneous CFR can be achieved in PPP AR for global users. At user end, higher CFR could be achieved with longer observations. The average CFR for 30-min, 1-h, 2-h and 4-h observation is 92.3, 98.2, 99.5 and 99.7 %, respectively. In order to get acceptable CFR, 1 h is a recommended minimum observation time. Furthermore, the CFR of PPP can be affected by diurnal variation and geomagnetic latitude variation in the ionosphere. During one day at the hours when rapid ionospheric variations occur or in low geomagnetic latitude regions where equatorial electron density irregularities are produced relatively frequently, a significant degradation of the CFR is demonstrated.
NASA Astrophysics Data System (ADS)
Saadati, Reza; Vaezpour, S. Mansour; Cho, Yeol J.
2009-06-01
In this paper, we apply an intuitionistic fuzzy quasi-metric version of a fixed point theorem, to obtain the existence of solution for a recurrence equation associated with the analysis of Quicksort algorithms.
NASA Astrophysics Data System (ADS)
Lampitt, Richard; Cristini, Luisa; Alexiou, Sofia
2015-04-01
The Fixed point Open Ocean Observatory network (FixO3, http://www.fixo3.eu/ ) integrates 23 European open ocean fixed point observatories and improves access to these infrastructures for the broader community. These provide multidisciplinary observations in all parts of the oceans from the air-sea interface to the deep seafloor. Started in September 2013 with a budget of 7 Million Euros over 4 years, the project has 29 partners drawn from academia, research institutions and SME's coordinated by the National Oceanography Centre, UK. Here we present the programme's achievements in the 18 months and the activities of the 12 Work Packages which have the objectives to: • integrate and harmonise the current procedures and processes • offer free access to observatory infrastructures to those who do not have such access, and free and open data services and products • innovate and enhance the current capability for multidisciplinary in situ ocean observation Open ocean observation is a high priority for European marine and maritime activities. FixO3 provides important data and services to address the Marine Strategy Framework Directive and in support of the European Integrated Maritime Policy. FixO3 provides a strong integrated framework of open ocean facilities in the Atlantic from the Arctic to the Antarctic and throughout the Mediterranean, enabling an integrated, regional and multidisciplinary approach to understand natural and anthropogenic change in the ocean.
Fixed points and stability in the two-network frustrated Kuramoto model
NASA Astrophysics Data System (ADS)
Kalloniatis, Alexander C.; Zuparic, Mathew L.
2016-04-01
We examine a modification of the Kuramoto model for phase oscillators coupled on a network. Here, two populations of oscillators are considered, each with different network topologies, internal and cross-network couplings and frequencies. Additionally, frustration parameters for the interactions of the cross-network phases are introduced. This may be regarded as a model of competing populations: internal to any one network phase synchronisation is a target state, while externally one or both populations seek to frequency synchronise to a phase in relation to the competitor. We conduct fixed point analyses for two regimes: one, where internal phase synchronisation occurs for each population with the potential for instability in the phase of one population in relation to the other; the second where one part of a population remains fixed in phase in relation to the other population, but where instability may occur within the first population leading to 'fragmentation'. We compare analytic results to numerical solutions for the system at various critical thresholds.
NASA Astrophysics Data System (ADS)
Bhole, Gaurav; Anjusha, V. S.; Mahesh, T. S.
2016-04-01
A robust control over quantum dynamics is of paramount importance for quantum technologies. Many of the existing control techniques are based on smooth Hamiltonian modulations involving repeated calculations of basic unitaries resulting in time complexities scaling rapidly with the length of the control sequence. Here we show that bang-bang controls need one-time calculation of basic unitaries and hence scale much more efficiently. By employing a global optimization routine such as the genetic algorithm, it is possible to synthesize not only highly intricate unitaries, but also certain nonunitary operations. We demonstrate the unitary control through the implementation of the optimal fixed-point quantum search algorithm in a three-qubit nuclear magnetic resonance (NMR) system. Moreover, by combining the bang-bang pulses with the crusher gradients, we also demonstrate nonunitary transformations of thermal equilibrium states into effective pure states in three- as well as five-qubit NMR systems.
NASA Technical Reports Server (NTRS)
Shimada, Seiichi; Bock, Yehuda
1992-01-01
Results are presented from temporally dense measurements of crustal deformation associated with the convergence of the Eurasian (EUR), Pacific, North American, and Philippine Sea (PHS) plates, carried out in April 1988 by a 10-station GPS fixed-point network established in central Japan. Using regional orbit relaxation methods, the analysis of the first 17-month data revealed significant horizontal deformation across the Suruga trough. Namely, it was found that a site in the northern tip of PHS plate moved nearly westward with a velocity of 28 +/-5 mm per year, and a site at the southeastern tip of EUR plate moved south-southwestward with a velocity of 18 +/-5 mm per year. A significant vertical uplift with a velocity of 20 mm/yr was detected at a site inland of the Tokai district located in the Akaishi uplift zone and at a site on the Hatsushima Island in Sagami Bay.
Progress report for the CCT-WG5 high temperature fixed point research plan
Machin, G.; Woolliams, E. R.; Anhalt, K.; Bloembergen, P.; Sadli, M.; Yamada, Y.
2013-09-11
An overview of the progress in High Temperature Fixed Point (HTFP) research conducted under the auspices of the CCT-WG5 research plan is reported. In brief highlights are: Provisional long term stability of HTFPs has been demonstrated. Optimum construction methods for HTFPs have been established and high quality HTFPs of Co-C, Pt-C and Re-C have been constructed for thermodynamic temperature assignment. The major sources of uncertainty in the assignment of thermodynamic temperature have been identified and quantified. The status of absolute radiometric temperature measurement has been quantified through the circulation of a set of HTFPs. The measurement campaign to assign low uncertainty thermodynamic temperatures to a selected set of HTFPs will begin in mid-2012. It is envisaged that this will be complete by 2015 leading to HTFPs becoming routine reference standards for radiometry and high temperature metrology.
Matrix triangularization by fixed-point redundant CORDIC with constant scale factor
NASA Astrophysics Data System (ADS)
Lee, Jeong-A.; Lang, Tomas
1990-11-01
We develop a redundani CORDIC scheme where the scale factor is forced to be constant while computing angles for 2 x 1 plane rotations. Based on the scheme we present a fixed-point implementation of matrix triangularization by Luk''s parallel algorithm with the following additional features: (1) the final scaling operation is done by shifting (2) the number of iterations in CORDIC rotation unit is reduced by about 25 by expressing the direction of the rotation in radix-2 and radix-4 and (3) the conventional number representation of rotated output is obtained on-thefly not from a carry-propagate adder. The number of hardware modules and the speed are evaluated and compared with the previous CORDIC schemes.
Bratu's problem: A novel approach using fixed-point iterations and Green's functions
NASA Astrophysics Data System (ADS)
Kafri, H. Q.; Khuri, S. A.
2016-01-01
In this article, the one-dimensional non-linear Bratu's boundary value problem is solved via a novel approach that combines Green's function and fixed point iterative schemes, such as Picard's and Krasnoselskii-Mann's. The convergence of the introduced iterative algorithm is proved using the contraction principle. The method is supported by considering a number of numerical examples that correspond to different cases of eigenvalues. The procedure underlying the strategy reduces calculations and provides highly accurate results in comparison with the exact solution and/or numerical solutions provided in the literature. The current method overcomes the difficulty of treating the problem for eigenvalues near and at the critical value, such as λ = 3 and λ = 3.51, and handles them reliably and very efficiently.
NASA Astrophysics Data System (ADS)
Hoyos Velasco, Fredy Edimer; García, Nicolás Toro; Garcés Gómez, Yeison Alberto
In this paper, the output voltage of a buck power converter is controlled by means of a quasi-sliding scheme. The Fixed Point Inducting Control (FPIC) technique is used for the control design, based on the Zero Average Dynamics (ZAD) strategy, including load estimation by means of the Least Mean Squares (LMS) method. The control scheme is tested in a Rapid Control Prototyping (RCP) system based on Digital Signal Processing (DSP) for dSPACE platform. The closed loop system shows adequate performance. The experimental and simulation results match. The main contribution of this paper is to introduce the load estimator by means of LMS, to make ZAD and FPIC control feasible in load variation conditions. In addition, comparison results for controlled buck converter with SMC, PID and ZAD-FPIC control techniques are shown.
A fast multi-level method for the fixed point form of matrix H-equations
Kelley, C.T. ); Northrup, J.I. )
1993-01-01
In previous work quasi-Newton and multi-level algorithms for fully nonlinear integral equations were designed and analyzed. The motivating examples for that work were analogs of the Chandrasekhar H-equation for matrix-valued functions. A weakness of these algorithms was that transfer between grids was done with a piecewise linear interpolation instead of Nystroem interpolation. This choice of interpolation was used because the nonlinearity in the Chandrasekhar equation was expressed in the quadratic form for which a matrix inversion is not required. In this paper the fixed point formulation is reconsidered and a conditioning issue associated with the matrix is resolved. This allows use of Nystroem interpolation and thereby a more efficient multi-level method. Implementation details on the Alliant FX series of multiprocessor computers is also discussed. 18 refs., 3 tabs.
Holographic non-relativistic fermionic fixed point by the charged dilatonic black hole
NASA Astrophysics Data System (ADS)
Li, Wei-Jia; Meyer, René; Zhang, Hongbao
2012-01-01
Driven by the landscape of garden-variety condensed matter systems, we have investigated how the dual spectral function behaves at the non-relativistic as well as relativistic fermionic fixed point by considering the probe Dirac fermion in an extremal charged dilatonic black hole with zero entropy. Although the pattern for both of the appearance of flat band and emergence of Fermi surface is qualitatively similar to that given by the probe fermion in the extremal Reissner-Nordstrom AdS black hole, we find a distinctly different low energy behavior around the Fermi surface, which can be traced back to the different near horizon geometry. In particular, with the peculiar near horizon geometry of our extremal charged dilatonic black hole, the low energy behavior exhibits the universal linear dispersion relation and scaling property, where the former indicates that the dual liquid is a Fermi one while the latter implies that the dual liquid is not exactly of Landau Fermi type.
Point and Fixed Plot Sampling Inventory Estimates at the Savannah River Site, South Carolina.
Parresol, Bernard, R.
2004-02-01
This report provides calculation of systematic point sampling volume estimates for trees greater than or equal to 5 inches diameter breast height (dbh) and fixed radius plot volume estimates for trees < 5 inches dbh at the Savannah River Site (SRS), Aiken County, South Carolina. The inventory of 622 plots was started in March 1999 and completed in January 2002 (Figure 1). Estimates are given in cubic foot volume. The analyses are presented in a series of Tables and Figures. In addition, a preliminary analysis of fuel levels on the SRS is given, based on depth measurements of the duff and litter layers on the 622 inventory plots plus line transect samples of down coarse woody material. Potential standing live fuels are also included. The fuels analyses are presented in a series of tables.
Infrared cameras are potential traceable "fixed points" for future thermometry studies.
Yap Kannan, R; Keresztes, K; Hussain, S; Coats, T J; Bown, M J
2015-01-01
The National physical laboratory (NPL) requires "fixed points" whose temperatures have been established by the International Temperature Scale of 1990 (ITS 90) be used for device calibration. In practice, "near" blackbody radiators together with the standard platinum resistance thermometer is accepted as a standard. The aim of this study was to report the correlation and limits of agreement (LOA) of the thermal infrared camera and non-contact infrared temporal thermometer against each other and the "near" blackbody radiator. Temperature readings from an infrared thermography camera (FLIR T650sc) and a non-contact infrared temporal thermometer (Hubdic FS-700) were compared to a near blackbody (Hyperion R blackbody model 982) at 0.5 °C increments between 20-40 °C. At each increment, blackbody cavity temperature was confirmed with the platinum resistance thermometer. Measurements were taken initially with the thermal infrared camera followed by the infrared thermometer, with each device mounted in turn on a stand at a fixed distance of 20 cm and 5 cm from the blackbody aperture, respectively. The platinum thermometer under-estimated the blackbody temperature by 0.015 °C (95% LOA: -0.08 °C to 0.05 °C), in contrast to the thermal infrared camera and infrared thermometer which over-estimated the blackbody temperature by 0.16 °C (95% LOA: 0.03 °C to 0.28 °C) and 0.75 °C (95% LOA: -0.30 °C to 1.79 °C), respectively. Infrared thermometer over-estimates thermal infrared camera measurements by 0.6 °C (95% LOA: -0.46 °C to 1.65 °C). In conclusion, the thermal infrared camera is a potential temperature reference "fixed point" that could substitute mercury thermometers. However, further repeatability and reproducibility studies will be required with different models of thermal infrared cameras. PMID:26468981
Bilateral comparison of tin fixed point cells between INMETRO and NPL
NASA Astrophysics Data System (ADS)
Silva, R. da; Veltcheva, R. I.; Gray, J.; Pearce, J. V.; Machin, G.; Teixeira, R. N.
2013-09-01
In April 2011, a bilateral comparison of tin fixed point cells (231.928 °C) took place at the facilities of the Temperature group at the National Physical Laboratory (NPL). The comparison was with a standard from the Thermal Metrology Division of the National Institute of Metrology, Quality and Technology (INMETRO). It involved two cells: the test cell was an open one constructed in late 2010 at the INMETRO Thermometry Laboratory as part of an MSc research project; the reference cell was a sealed one, constructed in 2000 at NPL, traceable to the UK national standard tin point. The materials employed in the construction of the cells were from different suppliers. The cell design, dimensions and construction procedures were also different. Three standard platinum resistance thermometers (SPRTs), each different models from different manufacturers, were used to undertake the comparison, one from INMETRO and two from NPL. The comparison was performed in quadruplicate, each combination using a different freezing plateau. The differing self-heating behaviour of the different SPRTs was taken into account. The methodology employed in this comparison is detailed in the present paper.
Sensitivity of collective action to uncertainty about climate tipping points
NASA Astrophysics Data System (ADS)
Barrett, Scott; Dannenberg, Astrid
2014-01-01
Despite more than two decades of diplomatic effort, concentrations of greenhouse gases continue to trend upwards, creating the risk that we may someday cross a threshold for `dangerous' climate change. Although climate thresholds are very uncertain, new research is trying to devise `early warning signals' of an approaching tipping point. This research offers a tantalizing promise: whereas collective action fails when threshold uncertainty is large, reductions in this uncertainty may bring about the behavioural change needed to avert a climate `catastrophe'. Here we present the results of an experiment, rooted in a game-theoretic model, showing that behaviour differs markedly either side of a dividing line for threshold uncertainty. On one side of the dividing line, where threshold uncertainty is relatively large, free riding proves irresistible and trust illusive, making it virtually inevitable that the tipping point will be crossed. On the other side, where threshold uncertainty is small, the incentive to coordinate is strong and trust more robust, often leading the players to avoid crossing the tipping point. Our results show that uncertainty must be reduced to this `good' side of the dividing line to stimulate the behavioural shift needed to avoid `dangerous' climate change.
Rapid re-convergences to ambiguity-fixed solutions in precise point positioning
NASA Astrophysics Data System (ADS)
Geng, Jianghui; Meng, Xiaolin; Dodson, Alan H.; Ge, Maorong; Teferle, Felix N.
2010-12-01
Integer ambiguity resolution at a single receiver can be achieved if the fractional-cycle biases are separated from the ambiguity estimates in precise point positioning (PPP). Despite the improved positioning accuracy by such integer resolution, the convergence to an ambiguity-fixed solution normally requires a few tens of minutes. Even worse, these convergences can repeatedly occur on the occasion of loss of tracking locks for many satellites if an open sky-view is not constantly available, consequently totally destroying the practicability of real-time PPP. In this study, in case of such re-convergences, we develop a method in which ionospheric delays are precisely predicted to significantly accelerate the integer ambiguity resolution. The effectiveness of this method consists in two aspects: first, wide-lane ambiguities can be rapidly resolved using the ionosphere-corrected wide-lane measurements, instead of the noisy Melbourne-Wübbena combination measurements; second, narrow-lane ambiguity resolution can be accelerated under the tight constraints derived from the ionosphere-corrected unambiguous wide-lane measurements. In the test at 90 static stations suffering from simulated total loss of tracking locks, 93.3 and 95.0% of re-convergences to wide-lane and narrow-lane ambiguity resolutions can be achieved within five epochs of 1-Hz measurements, respectively, even though the time latency for the predicted ionospheric delays is up to 180 s. In the test at a mobile van moving in a GPS-adverse environment where satellite number significantly decreases and cycle slips frequently occur, only when the predicted ionospheric delays are applied can the rate of ambiguity-fixed epochs be dramatically improved from 7.7 to 93.6% of all epochs. Therefore, this method can potentially relieve the unrealistic requirement of a continuous open sky-view by most PPP applications and improve the practicability of real-time PPP.
Kim, Do-Hyoung; Han, Mi-Ran; Lee, Gyunghee; Lee, Sang Soo; Kim, Young-Joon; Adams, Michael E.
2015-01-01
The ecdysis behavioral sequence in insects is a classic fixed action pattern (FAP) initiated by hormonal signaling. Ecdysis triggering hormones (ETHs) release the FAP through direct actions on the CNS. Here we present evidence implicating two groups of central ETH receptor (ETHR) neurons in scheduling the first two steps of the FAP: kinin (aka drosokinin, leucokinin) neurons regulate pre-ecdysis behavior and CAMB neurons (CCAP, AstCC, MIP, and Bursicon) initiate the switch to ecdysis behavior. Ablation of kinin neurons or altering levels of ETH receptor (ETHR) expression in these neurons modifies timing and intensity of pre-ecdysis behavior. Cell ablation or ETHR knockdown in CAMB neurons delays the switch to ecdysis, whereas overexpression of ETHR or expression of pertussis toxin in these neurons accelerates timing of the switch. Calcium dynamics in kinin neurons are temporally aligned with pre-ecdysis behavior, whereas activity of CAMB neurons coincides with the switch from pre-ecdysis to ecdysis behavior. Activation of CCAP or CAMB neurons through temperature-sensitive TRPM8 gating is sufficient to trigger ecdysis behavior. Our findings demonstrate that kinin and CAMB neurons are direct targets of ETH and play critical roles in scheduling successive behavioral steps in the ecdysis FAP. Moreover, temporal organization of the FAP is likely a function of ETH receptor density in target neurons. PMID:26401953
Realization of the WC-C peritectic fixed point at NIM and NMIJ
Wang, T.; Bai, C.; Yuan, Z.; Dong, W.; Lu, X.; Sasajima, N.; Yamada, Y.; Ara, C.
2013-09-11
Three WC-C peritectic fixed point cells, constructed from different sources of tungsten with different nominal purities, were measured at NIM and NMIJ. The three cells were constructed at NMIJ by NIM and NMIJ staffs, and T{sub 90} values of the three cells were measured at NMIJ during the period 31 Aug. to 25 Dec. 2009. Thereafter, the three cells were then transported to NIM, and T{sub 90} values of these cells were measured from 7 Dec. 2011 to 9 Jan. 2012. The results showed that T{sub 90} values of the three cells measured at the two institutes agreed within 0.4 °C with the combined scale comparison uncertainty of 1.7 °C (k= 2). The main component of the uncertainty is not the uncertainty due to impurities of the cells but the scale uncertainty and the stability of the measurement system. From these results it can be concluded that the WC-C cell is stable enough to provide new means of international high-temperature scale comparison above 3000 K.
NASA Astrophysics Data System (ADS)
Yokoyama, Yoshiaki; Kim, Minseok; Arai, Hiroyuki
At present, when using space-time processing techniques with multiple antennas for mobile radio communication, real-time weight adaptation is necessary. Due to the progress of integrated circuit technology, dedicated processor implementation with ASIC or FPGA can be employed to implement various wireless applications. This paper presents a resource and performance evaluation of the QRD-RLS systolic array processor based on fixed-point CORDIC algorithm with FPGA. In this paper, to save hardware resources, we propose the shared architecture of a complex CORDIC processor. The required precision of internal calculation, the circuit area for the number of antenna elements and wordlength, and the processing speed will be evaluated. The resource estimation provides a possible processor configuration with a current FPGA on the market. Computer simulations assuming a fading channel will show a fast convergence property with a finite number of training symbols. The proposed architecture has also been implemented and its operation was verified by beamforming evaluation through a radio propagation experiment.
NASA Astrophysics Data System (ADS)
Mishra, Puneet; Singla, Sunil Kumar
2013-01-01
In the modern world of automation, biological signals, especially Electroencephalogram (EEG) and Electrocardiogram (ECG), are gaining wide attention as a source of biometric information. Earlier studies have shown that EEG and ECG show versatility with individuals and every individual has distinct EEG and ECG spectrum. EEG (which can be recorded from the scalp due to the effect of millions of neurons) may contain noise signals such as eye blink, eye movement, muscular movement, line noise, etc. Similarly, ECG may contain artifact like line noise, tremor artifacts, baseline wandering, etc. These noise signals are required to be separated from the EEG and ECG signals to obtain the accurate results. This paper proposes a technique for the removal of eye blink artifact from EEG and ECG signal using fixed point or FastICA algorithm of Independent Component Analysis (ICA). For validation, FastICA algorithm has been applied to synthetic signal prepared by adding random noise to the Electrocardiogram (ECG) signal. FastICA algorithm separates the signal into two independent components, i.e. ECG pure and artifact signal. Similarly, the same algorithm has been applied to remove the artifacts (Electrooculogram or eye blink) from the EEG signal.
NASA Astrophysics Data System (ADS)
Piñeiro Orioli, Asier; Boguslavski, Kirill; Berges, Jürgen
2015-07-01
We investigate universal behavior of isolated many-body systems far from equilibrium, which is relevant for a wide range of applications from ultracold quantum gases to high-energy particle physics. The universality is based on the existence of nonthermal fixed points, which represent nonequilibrium attractor solutions with self-similar scaling behavior. The corresponding dynamic universality classes turn out to be remarkably large, encompassing both relativistic as well as nonrelativistic quantum and classical systems. For the examples of nonrelativistic (Gross-Pitaevskii) and relativistic scalar field theory with quartic self-interactions, we demonstrate that infrared scaling exponents as well as scaling functions agree. We perform two independent nonperturbative calculations, first by using classical-statistical lattice simulation techniques and second by applying a vertex-resummed kinetic theory. The latter extends kinetic descriptions to the nonperturbative regime of overoccupied modes. Our results open new perspectives to learn from experiments with cold atoms aspects about the dynamics during the early stages of our universe.
Assessment of tungsten/rhenium thermocouples with metal-carbon eutectic fixed points up to 1500°C
Gotoh, M.
2013-09-11
Four Type A thermocouples and two Type C thermocouples were calibrated at the Au fixed point and Co-C and Pd-C eutectic fixed points. The thermocouples were exposed to 1330 °C for a total of 100 hours. The maximum drift due to the exposure was found to be 4.8 °C. The fixed-point calibration EMF of these thermocouples deviated by less than 0.86% from the temperature specified by the standards ASTM E230-2003 for Type C and GOSTR 8.585-2001 for Type A. The length of one of Type A thermocouples A52 is longer than the others by 150mm. Making use of this provision it was possible to place annealed part of A52 to the temperature gradient part of calibration arrangement every time. Therefore observed aging effect was as low as 0.5 °C compared to the other thermocouples.
Hao, X.; Yuan, Z.; Wang, J.; Lu, X.
2013-09-11
In this paper, we describe an InGaAs detector based radiation thermometer (IRT) and new design of fixed-point blackbodies, including Sn, Zn, Al and Cu, for the establishment of a temperature scale from 200 °C to 1085 °C at the National Institute of Metrology of China. The construction and calibration of the IRT with the four fixed-point blackbodies are described. Characteristics of the IRT, such as the size-of-source effect, the amplifier performance and its stability are determined. The design of the four fixed-points, with 10 mm diameter of aperture and 0.9999 emissivity, is described. The uncertainty of the scale realization is elaborated.
NASA Astrophysics Data System (ADS)
Hao, X.; Yuan, Z.; Wang, J.; Lu, X.
2013-09-01
In this paper, we describe an InGaAs detector based radiation thermometer (IRT) and new design of fixed-point blackbodies, including Sn, Zn, Al and Cu, for the establishment of a temperature scale from 200 °C to 1085 °C at the National Institute of Metrology of China. The construction and calibration of the IRT with the four fixed-point blackbodies are described. Characteristics of the IRT, such as the size-of-source effect, the amplifier performance and its stability are determined. The design of the four fixed-points, with 10 mm diameter of aperture and 0.9999 emissivity, is described. The uncertainty of the scale realization is elaborated.
Chiampi, M.; Repetto, M.; Chiarabaglio, D.
1995-11-01
The hysteresis phenomenon can significantly affect the behavior of magnetic cores in electrical machines and devices. This paper presents a finite element solution of periodic steady state magnetic field problems in soft materials with scalar hysteresis. The Jiles-Atherton model is employed for the generation of symmetric B-H loops and it is coupled with the Fixed Point Technique for handling magnetic nonlinearities. The proposed procedure is applied to a hysteretic model problem whose analytical solution is available. The results show that the Fixed Point Technique can efficiently deal with non-single valued material characteristics under periodic operating conditions.
Buckley, Christopher L; Nowotny, Thomas
2012-01-24
Significant insights into the dynamics of neuronal populations have been gained in the olfactory system where rich spatio-temporal dynamics is observed during, and following, exposure to odours. It is now widely accepted that odour identity is represented in terms of stimulus-specific rate patterning observed in the cells of the antennal lobe (AL). Here we describe a nonlinear dynamical framework inspired by recent experimental findings which provides a compelling account of both the origin and the function of these dynamics. We start by analytically reducing a biologically plausible conductance based model of the AL to a quantitatively equivalent rate model and construct conditions such that the rate dynamics are well described by a single globally stable fixed point (FP). We then describe the AL's response to an odour stimulus as rich transient trajectories between this stable baseline state (the single FP in absence of odour stimulation) and the odour-specific position of the single FP during odour stimulation. We show how this framework can account for three phenomena that are observed experimentally. First, for an inhibitory period often observed immediately after an odour stimulus is removed. Second, for the qualitative differences between the dynamics in the presence and the absence of odour. Lastly, we show how it can account for the invariance of a representation of odour identity to both the duration and intensity of an odour stimulus. We compare and contrast this framework with the currently prevalent nonlinear dynamical framework of 'winnerless competition' which describes AL dynamics in terms of heteroclinic orbits. This article is part of a Special Issue entitled "Neural Coding". PMID:21840510
The Influence of Titanium on the Aluminum Fixed-Point Temperature
NASA Astrophysics Data System (ADS)
Petchpong, Patchariya; Head, David I.
2011-08-01
This work describes the deliberate doping of high purity (99.9999 %) aluminum with titanium (99.8 %) impurity and the effect of this on the temperature of the aluminum liquid-solid phase transition (660.323 °C). The aluminum sample was in the form of an ~0.3 kg ingot (that would normally be used to realize an ITS-90 fixed point) which was doped at ~0.9 ppmw Ti and ~1.8 ppmw Ti (mass fraction in parts per million by mass). Measurements were made with procedures and equipment normally used in a metrological thermometry laboratory, rather than using special arrangements. Samples cut from the aluminum ingot were chemically analyzed by glow discharge mass spectrometry (GD-MS) before doping and after the second doping (to 1.8 ppmw). The experimental temperature offsets were compared with those calculated by interpolation from a reference book value using the mass of dopant introduced, or the chemical analysis data. The results showed that the aluminum temperature increased after adding 0.9 ppmw Ti, but apparently the temperature did not change after further doping to 1.8 ppmw Ti; which was unexpected. The first result suggested that titanium impurity increases the Al transition temperature by +5.1 mK · ppmw-1. However, using the (total) temperature offset and the GD-MS value for the (total) added Ti impurities, then one calculates a value of 3.4 mK · ppmw-1 (much closer to a reference book value). The experimental undoped liquid-solid transition curves were also compared against theoretical curves (calculated using a theoretical model "MTDATA"). This suggested that GD-MS may not be "exposing" all the active impurities (some of which may be "hidden" in the carbon background).
NASA Astrophysics Data System (ADS)
Castro, P.; Machin, G.; Bloembergen, P.; Lowe, D.; Whittam, A.
2014-07-01
This study forms part of the European Metrology Research Programme project implementing the New Kelvin to assign thermodynamic temperatures to a selected set of high-temperature fixed points (HTFPs), Cu, Co-C, Pt-C, and Re-C. A realistic thermal model of these HTFPs, developed in finite volume software ANSYS FLUENT, was constructed to quantify the uncertainty associated with the temperature drop across the back wall of the cell. In addition, the widely applied software package, STEEP3 was used to investigate the influence of cell emissivity. The temperature drop, , relates to the temperature difference due to the net loss of heat from the aperture of the cavity between the back wall of the cavity, viewed by the thermometer, defining the radiance temperature, and the solid-liquid interface of the alloy, defining the transition temperature of the HTFP. The actual value of can be used either as a correction (with associated uncertainty) to thermodynamic temperature evaluations of HTFPs, or as an uncertainty contribution to the overall estimated uncertainty. In addition, the effect of a range of furnace temperature profiles on the temperature drop was calculated and found to be negligible for Cu, Co-C, and Pt-C and small only for Re-C. The effective isothermal emissivity is calculated over the wavelength range from 450 nm to 850 nm for different assumed values of surface emissivity. Even when furnace temperature profiles are taken into account, the estimated emissivities change only slightly from the effective isothermal emissivity of the bare cell. These emissivity calculations are used to estimate the uncertainty in the temperature assignment due to the uncertainty in the emissivity of the blackbody.
L-Fuzzy Fixed Points Theorems for L-Fuzzy Mappings via βℱL-Admissible Pair
Rashid, Maliha; Azam, Akbar
2014-01-01
We define the concept of βℱL-admissible for a pair of L-fuzzy mappings and establish the existence of common L-fuzzy fixed point theorem. Our result generalizes some useful results in the literature. We provide an example to support our result. PMID:24688441
Formalin Fixed Paraffin Embedded Tissue as a Starting Point for PrPSc Detection by ELISA
Technology Transfer Automated Retrieval System (TEKTRAN)
Introduction: Formalin fixed paraffin embedded tissue are regularly employed in TSE diagnosis by IHC, the standard by which all other diagnostic protocols are currently judged. While IHC affords advantages over diagnostic approaches that typically utilize fresh or frozen tissue, such as Western blot...
NASA Astrophysics Data System (ADS)
Sadli, Mohamed; Bourson, Frédéric; Diril, Ahmet; Journeau, Christophe; Lowe, Dave; Parga, Clemente
2014-08-01
Among the activities of the European Metrology Research Programme (EMRP) project HiTeMS one work package is devoted to the development and testing of industrial solutions for long-standing temperature measurement problems at the highest temperatures. LNE-Cnam, NPL, TUBITAK-UME have worked on the design of high temperature fixed points (HTFP) suitable for in-situ temperature monitoring to be implemented in the facilities of CEA (Commissariat à l'énergie atomique et aux énergies alternatives). Several high temperature fixed point cells were constructed in these three national metrology institutes (NMIs) using a rugged version of cells based on the hybrid design of the laboratory HTFP developed and continuously improved at LNE-Cnam during the last years. The fixed points of interest were Co-C, Ru-C and Re-C corresponding to melting temperatures of 1324 °C, 1953 °C and 2474 °C respectively. The cells were characterised at the NMIs after their construction. Having proved robust enough, they were transported to CEA and tested in an induction furnace and cycled from room temperature to temperatures much above the melting temperatures (> +400 °C) with extremely high heating and cooling rates (up to 10 000 K/h). All the cells withstood the tests and the melting plateaus could be observed in all cases.
The EuroSITES network: Integrating and enhancing fixed-point open ocean observatories around Europe
NASA Astrophysics Data System (ADS)
Lampitt, Richard S.; Larkin, Kate E.; EuroSITES Consortium
2010-05-01
EuroSITES is a 3 year (2008-2011) EU collaborative project (3.5MEuro) with the objective to integrate and enhance the nine existing open ocean fixed point observatories around Europe (www.eurosites.info). These observatories are primarily composed of full depth moorings and make multidisciplinary in situ observations within the water column as the European contribution to the global array OceanSITES (www.oceansites.org). In the first 18 months, all 9 observatories have been active and integration has been significant through the maintenance and enhancement of observatory hardware. Highlights include the enhancement of observatories with sensors to measure O2, pCO2, chlorophyll, and nitrate in near real-time from the upper 1000 m. In addition, some seafloor missions are also actively supported. These include seafloor platforms currently deployed in the Mediterranean, one for tsunami detection and one to monitor fluid flow related to seismic activity and slope stability. Upcoming seafloor science missions in 2010 include monitoring benthic biological communities and associated biogeochemistry as indicators of climate change in both the Northeast Atlantic and Mediterranean. EuroSITES also promotes the development of innovative sensors and samplers in order to progress capability to measure climate-relevant properties of the ocean. These include further developing current technologies for autonomous long-term monitoring of oxygen consumption in the mesopelagic, pH and mesozooplankton abundance. Many of these science missions are directly related to complementary activities in other European projects such as EPOCA, HYPOX and ESONET. In 2010 a direct collaboration including in situ field work will take place between ESONET and EuroSITES. The demonstration mission MODOO (funded by ESONET) will be implemented in 2010 at the EuroSITES PAP observatory. Field work will include deployment of a seafloor lander system with various sensors which will send data to shore in real time via the EuroSITES water column infrastructure. EuroSITES Data management is led by NOCS, UK with CORIOLIS, France as one of the Global Data assembly centre (GDAC) for both EuroSITES and OceanSITES. EuroSITES maintains the OceanSITES and GEO philosophy of open access to data in near real-time. With a common data policy and standardised data formats (OceanSITES NetCDF) EuroSITES is increasing the potential users of in situ ocean datasets and the societal benefit of these data. For instance, CORIOLIS is central to the ever increasing contribution of EuroSITES as an upstream data provider to the GMES project MyOcean (both real-time and delayed-mode data). Outreach and knowledge transfer of EuroSITES activities and results are also a key component to the project with a dedicated outreach website, Fact Sheet, cruise diaries and educational tools being developed in the first 18 months. In 2010 a film will be released to represent the network and this will be distributed to a wide audience through the European network of aquaria and at other outreach events. In addition, the EuroSITES project and it's relevance to global ocean observation initiatives continues to be actively promoted at both scientific and non-specialist meetings and events. By the end of EuroSITES in April 2011, the 9 core ocean observatories will be well integrated. Each observatory will have enhanced infrastructure to include both physical and biogeoechemical sensors. Science missions in the ocean interior and seafloor/subseafloor will have progressed European ocean observational capability significantly. Collaborations will have taken place or will be at an advanced stage of planning with related European and international projects including ESONET FP6 NoE and the NSF funded Ocean Observatories Initiative (OOI) (400M over 5 years). EuroSITES will continue to develop it's contribution to the ocean component of the Group on Earth Observations (GEO) through task AR-09-03c 'Global Ocean Observing Systems' and related societal benefit areas.
Two-stage fixed-bed gasifier with selectable middle gas off-take point
Strickland, Larry D.; Bissett, Larry A.
1992-01-01
A two-stage fixed bed coal gasifier wherein an annular region is in registry with a gasification zone underlying a devolatilization zone for extracting a side stream of high temperature substantially tar-free gas from the gasifier. A vertically displaceable skirt means is positioned within the gasifier to define the lower portion of the annular region so that vertical displacement of the skirt means positions the inlet into the annular region in a selected location within or in close proximity to the gasification zone for providing a positive control over the composition of the side stream gas.
Kaithwas, Gaurav; Majumdar, Dipak K
2010-06-01
The aim of the study was to evaluate the antiulcer activity of Linum usitatissimum fixed oil against aspirin-, indomethacin-, ethanol-, reserpine-, serotonin- and stress-induced gastric ulceration in rats and histamine-induced gastric ulceration in guinea pigs. Attempts were also made to evaluate the in vitro anticholinergic and antihistaminic activity and in vivo antisecretary and antiulcer activity of oil following pylorus ligation in rats. L. usitatissimum fixed oil exhibited significant antiulcer activity against different ulcerogens in experimental animal models. The fixed oil significantly inhibited acetylcholine- and histamine-induced contraction of guinea pig and rat ileums, respectively, suggesting its anticholinergic and antihistaminic activity. The oil also exhibited significant inhibitory effect on gastric secretion/total acidity and aspirin-induced gastric ulceration in pylorus-ligated rats. The lipoxygenase inhibitory, histamine antagonistic and antisecretory (anticholinergic) effects of the oil could probably have contributed towards antiulcer activity. L. usitatissimum fixed oil may be considered to be a drug of natural origin which possesses significant antiulcer activity. The present observation is the first experimental data showing antiulcer activity of L. usitatissimum fixed oil. PMID:20405222
NASA Astrophysics Data System (ADS)
Gehring, Friedrich; Gies, Holger; Janssen, Lukas
2015-10-01
We investigate a class of relativistic fermion theories in 2
Nogawa, Tomoaki; Hasegawa, Takehisa; Nemoto, Koji
2012-09-01
We study the Ising model in a hierarchical small-world network by renormalization group analysis and find a phase transition between an ordered phase and a critical phase, which is driven by the coupling strength of the shortcut edges. Unlike ordinary phase transitions, which are related to unstable renormalization fixed points (FPs), the singularity in the ordered phase of the present model is governed by the FP that coincides with the stable FP of the ordered phase. The weak stability of the FP yields peculiar criticalities, including logarithmic behavior. On the other hand, the critical phase is related to a nontrivial FP, which depends on the coupling strength and is continuously connected to the ordered FP at the transition point. We show that this continuity indicates the existence of a finite correlation-length-like quantity inside the critical phase, which diverges upon approaching the transition point. PMID:23030852
Kainz, K; Prah, D; Ahunbay, E; Li, X
2014-06-01
Purpose: A novel modulated arc therapy technique, mARC, enables superposition of step-and-shoot IMRT segments upon a subset of the optimization points (OPs) of a continuous-arc delivery. We compare two approaches to mARC planning: one with the number of OPs fixed throughout optimization, and another where the planning system determines the number of OPs in the final plan, subject to an upper limit defined at the outset. Methods: Fixed-OP mARC planning was performed for representative cases using Panther v. 5.01 (Prowess, Inc.), while variable-OP mARC planning used Monaco v. 5.00 (Elekta, Inc.). All Monaco planning used an upper limit of 91 OPs; those OPs with minimal MU were removed during optimization. Plans were delivered, and delivery times recorded, on a Siemens Artiste accelerator using a flat 6MV beam with 300 MU/min rate. Dose distributions measured using ArcCheck (Sun Nuclear Corporation, Inc.) were compared with the plan calculation; the two were deemed consistent if they agreed to within 3.5% in absolute dose and 3.5 mm in distance-to-agreement among > 95% of the diodes within the direct beam. Results: Example cases included a prostate and a head-and-neck planned with a single arc and fraction doses of 1.8 and 2.0 Gy, respectively. Aside from slightly more uniform target dose for the variable-OP plans, the DVHs for the two techniques were similar. For the fixed-OP technique, the number of OPs was 38 and 39, and the delivery time was 228 and 259 seconds, respectively, for the prostate and head-and-neck cases. For the final variable-OP plans, there were 91 and 85 OPs, and the delivery time was 296 and 440 seconds, correspondingly longer than for fixed-OP. Conclusion: For mARC, both the fixed-OP and variable-OP approaches produced comparable-quality plans whose delivery was successfully verified. To keep delivery time per fraction short, a fixed-OP planning approach is preferred.
Mulheran, P A; O'Neill, K P; Grinfeld, M; Lamb, W
2012-11-01
The distributions of interisland gaps and captures zones for islands nucleated on a one-dimensional substrate during submonolayer deposition are considered using a novel retrospective view. This provides an alternative perspective on why scaling occurs in this continuously evolving system. Distributional fixed-point equations for the gaps are derived both with and without a mean-field approximation for nearest neighbor gap-size correlation. Solutions to the equations show that correct consideration of fragmentation bias justifies the mean-field approach, which can be extended to provide closed-from equations for the capture zones. Our results compare favorably to Monte Carlo data for both point and extended islands using a range of critical island size i=0,1,2,3. We also find satisfactory agreement with theoretical models based on more traditional fragmentation theory approaches. PMID:23214792
NASA Astrophysics Data System (ADS)
Rezaie, B.; Jahed Motlagh, M. R.; Analoui, M.; Khorsandi, S.
2009-10-01
This paper deals with the problem of Hopf bifurcation control for a class of nonlinear time-delay systems. A dynamic delayed feedback control method is utilized for stabilizing unstable fixed points near Hopf bifurcation. Using a linear stability analysis, we show that under certain conditions of the control parameters, and without changing the operating point of the system, the onset of Hopf bifurcation is delayed. Meanwhile, by applying the center manifold theorem and the normal form theory, we obtain formulas for determining the direction of the Hopf bifurcation and the stability of bifurcating periodic solutions of the closed loop system. Numerical simulations are given to justify the validity of the analytical results for the system controlled by the proposed method.
NASA Astrophysics Data System (ADS)
Pearce, J. V.; Machin, G.; Ford, T.; Wardle, S.
2008-02-01
Improvement of energy efficiency of jet aircraft is achieved by operating gas turbine engines at higher temperatures. To facilitate this, gas turbine engine manufacturers are continuously developing new alloys for hot-zone turbine blades that will withstand the increased in-service temperatures. A critical part of the manufacture of these blades is heat treatment to ensure that they attain the necessary metallurgical characteristics. Current heat-treatment temperature-control requirements are at the limit of what is achievable with conventional thermocouple calibrations. A project that will allow thermocouple manufacturer CCPI Europe Ltd. to realize uncertainties of 1C, or better, in the calibration of its noble metal thermocouples is described. This will be realized through implementing a Co C eutectic fixed point in CCPIs calibration chain. As this melts at 1,324C, very close to the heat-treatment temperatures required, low uncertainties will be obtained. This should yield an increase in effectiveness of the heat-treatment process performed by Bodycote Heat Treatments Ltd., allowing them to respond effectively to the increasingly stringent demands of engine manufacturers. Outside the current project, there is a strong requirement by industry for lower uncertainties at and above 1,300C. Successful implementation of the current fixed point in an industrial setting is likely to result in rapid take-up by other companies, probably through the supply of ultra-low uncertainty thermocouples, looking to improve their high-temperature processes.
Defenu, Nicoló; Trombettoni, Andrea; Codello, Alessandro
2015-11-01
We study, by renormalization group methods, O(N) models with interactions decaying as power law with exponent d+σ. When only the long-range momentum term p(σ) is considered in the propagator, the critical exponents can be computed from those of the corresponding short-range O(N) models at an effective fractional dimension D(eff). Neglecting wave function renormalization effects the result for the effective dimension is D(eff)=2d/σ, which turns to be exact in the spherical model limit (N→∞). Introducing a running wave function renormalization term the effective dimension becomes instead D(eff)=(2-η(SR))d/σ. The latter result coincides with the one found using standard scaling arguments. Explicit results in two and three dimensions are given for the exponent ν. We propose an improved method to describe the full theory space of the models where both short- and long-range propagator terms are present and no a priori choice among the two in the renormalization group flow is done. The eigenvalue spectrum of the full theory for all possible fixed points is drawn and a full description of the fixed-point structure is given, including multicritical long-range universality classes. The effective dimension is shown to be only approximate, and the resulting error is estimated. PMID:26651653
NASA Astrophysics Data System (ADS)
Liang, Yanfeng; Naqvi, Syed Mohsen; Chambers, Jonathon A.
2012-12-01
Fast fixed-point independent vector analysis (FastIVA) is an improved independent vector analysis (IVA) method, which can achieve faster and better separation performance than original IVA. As an example IVA method, it is designed to solve the permutation problem in frequency domain independent component analysis by retaining the higher order statistical dependency between frequencies during learning. However, the performance of all IVA methods is limited due to the dimensionality of the parameter space commonly encountered in practical frequency-domain source separation problems and the spherical symmetry assumed with the source model. In this article, a particular permutation problem encountered in using the FastIVA algorithm is highlighted, namely the block permutation problem. Therefore a new audio video based fast fixed-point independent vector analysis algorithm is proposed, which uses video information to provide a smart initialization for the optimization problem. The method cannot only avoid the ill convergence resulting from the block permutation problem but also improve the separation performance even in noisy and high reverberant environments. Different multisource datasets including the real audio video corpus AV16.3 are used to verify the proposed method. For the evaluation of the separation performance on real room recordings, a new pitch based evaluation criterion is also proposed.
NASA Astrophysics Data System (ADS)
Defenu, Nicoló; Trombettoni, Andrea; Codello, Alessandro
2015-11-01
We study, by renormalization group methods, O (N ) models with interactions decaying as power law with exponent d +σ . When only the long-range momentum term pσ is considered in the propagator, the critical exponents can be computed from those of the corresponding short-range O (N ) models at an effective fractional dimension Deff. Neglecting wave function renormalization effects the result for the effective dimension is Deff=2/d σ , which turns to be exact in the spherical model limit (N →∞ ) . Introducing a running wave function renormalization term the effective dimension becomes instead Deff=(2/-ηSR)d σ . The latter result coincides with the one found using standard scaling arguments. Explicit results in two and three dimensions are given for the exponent ν . We propose an improved method to describe the full theory space of the models where both short- and long-range propagator terms are present and no a priori choice among the two in the renormalization group flow is done. The eigenvalue spectrum of the full theory for all possible fixed points is drawn and a full description of the fixed-point structure is given, including multicritical long-range universality classes. The effective dimension is shown to be only approximate, and the resulting error is estimated.
Typical Orbits of Quadratic Polynomials with a Neutral Fixed Point: Brjuno Type
NASA Astrophysics Data System (ADS)
Cheraghi, Davoud
2013-09-01
We describe the topological behavior of typical orbits of complex quadratic polynomials {P_{α}(z) = e^{2 π α {i}} z + z2}, with α of high return type. Here we prove that for such Brjuno values of α the closure of the critical orbit, which is the measure theoretic attractor of the map, has zero area. Then we show that the limit set of the orbit of a typical point in the Julia set of P α is equal to the closure of the critical orbit. Our method is based on the near parabolic renormalization of Inou-Shishikura, and a uniform optimal estimate on the derivative of the Fatou coordinate that we prove here.
Construction of Home-Made Tin Fixed-Point Cell at TUBITAK UME
NASA Astrophysics Data System (ADS)
Kalemci, M.; Arifovic, N.; Bağçe, A.; Aytekin, S. O.; Ince, A. T.
2015-08-01
TUBITAK UME Temperature Laboratory initiated a new study which focuses on the construction of a tin freezing-point cell as a primary temperature standard. The design is an open-cell type similar to the National Institute of Standards and Technology design. With this aim, a brand new vacuum and filling line employing an oil diffusion pump and two cold traps (liquid nitrogen and dry ice) was set-up. The graphite parts (crucible, thermometer well, etc.) have been baked at high temperature under vacuum. Each cell was filled with approximately 1 kg of high-purity tin (99.9999 %) in a three-zone furnace. Then several melting and freezing curves were obtained to assess the quality of the home-made cell, and also the new cell was compared with the existing reference cell of the laboratory. The results obtained are very close to the reference cell of UME, indicating that the method used for fabrication was promising and satisfactory and also seems to meet the requirements to have a primary level temperature standard.
Numerical Modeling of Heat Flux in Fixed-Point Cells Due to the Hydrostatic-Head Effect
NASA Astrophysics Data System (ADS)
Batagelj, V.; Bojkovski, J.; Drnovšek, J.
2011-12-01
The article presents the numerical analysis of a particular thermal effect, which occurs during the calibration of standard platinum resistance thermometers in fixed-point cells. The temperature within the fixed-point cell varies linearly with the immersion depth due to the hydrostatic-head effect, so a quasi-linear temperature gradient in the vertical direction is inherently present. If there is a temperature gradient, a resulting heat flux will appear. This heat flux flows across the thermal conductivities, which change with depth, so the resulting temperature field is distorted. The key issue that is tackled in this article is the magnitude of these temperature deviations and their influence on the measurement accuracy. This effect should not be confused with the perturbing heat exchange toward the thermal enclosure and ambient. These are independent effects that are in real systems superimposed on each other. To get a better insight into this phenomenon, a numerical model based on a finite-difference method was developed. The model allows the simulation of the measurement of the thermometer immersion profile and of the use of different bushings, as two of the methods for assessing the thermal effects. The results of the modeling showed that there is an inherent difference between the temperature measured by the thermometer sensor and the temperature at the point of the phase transition, even if the immersion depth was infinite and there was no perturbing heat exchange toward the thermal enclosure and ambient. Nevertheless, in several cases the thermometer would still almost perfectly follow the immersion-profile curve. The only exception is near the bottom of the cell, where a small deviation from the immersion profile was observed. This is in agreement with previously presented experimental results, where this behavior was noticed, but never satisfactorily explained.
U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office
2004-04-28
This Corrective Action Decision Document (CADD) identifies and rationalizes the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office's selection of a recommended corrective action alternative appropriate to facilitate the closure of Corrective Action Unit (CAU) 516: Septic Systems and Discharge Points, Nevada Test Site (NTS), Nevada, under the Federal Facility Agreement and Consent Order. Located in Areas 3, 6, and 22 on the NTS, CAU 516 includes six Corrective Action Sites (CASs) consisting of two septic systems, a sump and piping, a clean-out box and piping, dry wells, and a vehicle decontamination area. Corrective action investigation activities were performed from July 22 through August 14, 2003, with supplemental sampling conducted in late 2003 and early 2004. The potential exposure pathways for any contaminants of concern (COCs) identified during the development of the DQOs at CAU 516 gave rise to the following objectives: (1) prevent or mitigate exposure to media containing COCs at concentrations exceeding PALs as defined in the corrective action investigation plan; and (2) prevent the spread of COCs beyond each CAS. The following alternatives have been developed for consideration at CAU 516: Alternative 1 - No Further Action; Alternative 2 - Clean Closure; and Alternative 3 - Closure in Place with Administrative Controls. Alternative 1, No Further Action, is the preferred corrective action for two CASs (06-51-02 and 22-19-04). Alternative 2, Clean Closure, is the preferred corrective action for four CASs (03-59-01, 03-59-02, 06-51-01, and 06-51-03). The selected alternatives were judged to meet all requirements for the technical components evaluated, as well as meeting all applicable state and federal regulations for closure of the site and will further eliminate the contaminated media at CAU 516.
A Phase-Field Solidification Model of Almost Pure ITS-90 Fixed Points
NASA Astrophysics Data System (ADS)
Large, M. J.; Pearce, J. V.
2014-07-01
A two-dimensional axisymmetric phase-field model of thermo-solutal solidification in freezing-point cells used for calibrating standard platinum resistance thermometers for realization and dissemination of the International Temperature Scale of 1990 is presented. The cell is essentially a graphite crucible containing an ingot of very pure metal (of order 99.9999 %). A graphite tube is inserted along the axis of the ingot to enable immersion of the thermometer in the metal. In this study, the metal is tin (freezing temperature of ). During the freezing of these cells, a steady, reproducible temperature is realized, with a defined temperature that can be used to calibrate thermometers with uncertainties mK. The model is applied to understand the effect of experimental parameters, such as initiation technique and furnace homogeneity, on the measured freezing curve. Results show that freezing curves whose behavior is consistent with the Scheil theory of solidification can be obtained with a specific furnace temperature profile, and provided that the freeze is of a long duration, the results are consistent with previous one-dimensional models and experiments. Morphological instability is observed with the inner interface initiation technique, causing the interface to adopt a cellular structure. This elevates the measured temperature, in accordance with the Gibbs-Thomson effect. In addition, the influence of initiation techniques on the solidification behavior is examined. The model indicates that an initially smooth inner mantle can `de-wet' from the thermometer well-forming agglomerated solid droplets, following recalescence, under certain conditions. This manifests as a measured temperature depression due to the Gibbs-Thomson effect, with a magnitude of to in simulations. The temperature rises to that of the stable outer mantle as freezing progresses and the droplets re-melt. It is demonstrated that the effect occurs below a critical mantle thickness. A physical explanation for the origin of the effect is offered showing that it is consistent with solid-state de-wetting phenomena. Consideration is also given to the limitations of the current model configuration.
NASA Astrophysics Data System (ADS)
Batagelj, V.; Bojkovski, J.; Drnovšek, J.; Pušnik, I.
2003-09-01
The following paper describes the influence of the self-heating of standard platinum resistance thermometers (SPRTs) on the uncertainty in fixed point calibration and calibration by comparison. The self-heating is a well-known phenomenon, which occurs, when the SPRT resistance is measured with a measurement current that dissipates power and therefore additionally heats up the SPRT sensor. A value of the self-heating at the measurement current of 1 mA is typically in the range from 0.2 mK to 5 mK, depending on the SPRT design, temperature and the surrounding medium. A series of measurements was performed in order to understand the behavior of the self-heating with different SPRT designs and measurement conditions. Procedures to reduce the uncertainty of self-heating correction are discussed and conclusions regarding uncertainty estimation are presented.
NASA Astrophysics Data System (ADS)
Belitz, D.; Kirkpatrick, T. R.
2014-01-01
We use scaling and renormalization-group techniques to analyze the leading nonanalyticities in a Fermi liquid. We show that a physically motivated scaling hypothesis reproduces the results known from perturbation theory for the density of states, the density-of-states fluctuations, the specific heat, the spin susceptibility, and the nematic magnetic susceptibility. We also discuss the absence of nonanalytic terms in the density susceptibility. We then use a recent effective field theory for clean electron systems to derive the scaling hypothesis by means of renormalization-group techniques. This shows that the exponents (although not the prefactors) of the nonanalyticities that were previously derived by means of perturbative techniques are indeed exact, and can be understood as the leading corrections to scaling at the stable Fermi-liquid fixed point.
Selbig, William R.; Bannerman, Roger T.
2011-01-01
The U.S Geological Survey, in cooperation with the Wisconsin Department of Natural Resources (WDNR) and in collaboration with the Root River Municipal Stormwater Permit Group monitored eight urban source areas representing six types of source areas in or near Madison, Wis. in an effort to improve characterization of particle-size distributions in urban stormwater by use of fixed-point sample collection methods. The types of source areas were parking lot, feeder street, collector street, arterial street, rooftop, and mixed use. This information can then be used by environmental managers and engineers when selecting the most appropriate control devices for the removal of solids from urban stormwater. Mixed-use and parking-lot study areas had the lowest median particle sizes (42 and 54 (u or mu)m, respectively), followed by the collector street study area (70 (u or mu)m). Both arterial street and institutional roof study areas had similar median particle sizes of approximately 95 (u or mu)m. Finally, the feeder street study area showed the largest median particle size of nearly 200 (u or mu)m. Median particle sizes measured as part of this study were somewhat comparable to those reported in previous studies from similar source areas. The majority of particle mass in four out of six source areas was silt and clay particles that are less than 32 (u or mu)m in size. Distributions of particles ranging from 500 (u or mu)m were highly variable both within and between source areas. Results of this study suggest substantial variability in data can inhibit the development of a single particle-size distribution that is representative of stormwater runoff generated from a single source area or land use. Continued development of improved sample collection methods, such as the depth-integrated sample arm, may reduce variability in particle-size distributions by mitigating the effect of sediment bias inherent with a fixed-point sampler.
DOE /NV
1999-06-19
This Corrective Action Decision Document (CADD) has been prepared for Corrective Action Unit (CAU) 423, Building 03-60 Underground Discharge Point (UDP) in accordance with the Federal Facility Agreement and Consent Order (FFACO) of 1996 that was agreed to by the US Department of Energy, Nevada Operations Office (DOE/NV); the Nevada Division of Environmental Protection (NDEP); and the U.S Department of Defense (FFACO, 1996). The CADD provides or references the specific information necessary to recommend a preferred corrective action for the single Corrective Action Site (CAS), 03-02-002-0308, within CAU 423. Corrective Action Unit 423 is located at the Tonopah Test Range (TTR), Nevada. The TTR is approximately 255 kilometers (km) (140 miles[mi]) northwest of Las Vegas, Nevada. The UDP is approximately 73 meters (m) (240 feet [ft]) northwest of the northwest corner of Building 03-60, the Auto Maintenance Shop. Corrective Action Unit 423 is comprised of the UDP and an associated discharge line extending from Building 03-60. The UDP received waste oil products from the Auto Maintenance Shop, a light-duty fleet maintenance shop in the Area 3 compound, from 1965 to 1989 or 1990 (DOE/NV, 1997).
K. B. Campbell
2002-06-01
This Corrective Action Plan (CAP) provides selected corrective action alternatives and proposes the closure methodology for Corrective Action Unit (CAU) 262, Area 25 Septic Systems and Underground Discharge Point. CAU 262 is identified in the Federal Facility Agreement and Consent Order (FFACO) of 1996. Remediation of CAU 262 is required under the FFACO. CAU 262 is located in Area 25 of the Nevada Test Site (NTS), approximately 100 kilometers (km) (62 miles [mi]) northwest of Las Vegas, Nevada. The nine Corrective Action Sites (CASs) within CAU 262 are located in the Nuclear Rocket Development Station complex. Individual CASs are located in the vicinity of the Reactor Maintenance, Assembly, and Disassembly (R-MAD); Engine Maintenance, Assembly, and Disassembly (E-MAD); and Test Cell C compounds. CAU 262 includes the following CASs as provided in the FFACO (1996); CAS 25-02-06, Underground Storage Tank; CAS 25-04-06, Septic Systems A and B; CAS 25-04-07, Septic System; CAS 25-05-03, Leachfield; CAS 25-05-05, Leachfield; CAS 25-05-06, Leachfield; CAS 25-05-08, Radioactive Leachfield; CAS 25-05-12, Leachfield; and CAS 25-51-01, Dry Well. Figures 2, 3, and 4 show the locations of the R-MAD, the E-MAD, and the Test Cell C CASs, respectively. The facilities within CAU 262 supported nuclear rocket reactor engine testing. Activities associated with the program were performed between 1958 and 1973. However, several other projects used the facilities after 1973. A significant quantity of radioactive and sanitary waste was produced during routine operations. Most of the radioactive waste was managed by disposal in the posted leachfields. Sanitary wastes were disposed in sanitary leachfields. Septic tanks, present at sanitary leachfields (i.e., CAS 25-02-06,2504-06 [Septic Systems A and B], 25-04-07, 25-05-05,25-05-12) allowed solids to settle out of suspension prior to entering the leachfield. Posted leachfields do not contain septic tanks. All CASs located in CAU 262 are inactive or abandoned. However, some leachfields may still receive liquids from runoff during storm events. Results from the 2000-2001 site characterization activities conducted by International Technology (IT) Corporation, Las Vegas Office are documented in the Corrective Action Investigation Report for Corrective Action Unit 262: Area 25 Septic Systems and Underground Discharge Point, Nevada Test Site, Nevada. This document is located in Appendix A of the Corrective Action Decision Document for CAU 262. Area 25 Septic Systems and Underground Discharge Point, Nevada Test Site, Nevada. (DOE/NV, 2001).
Perceiving the Direction of Articulatory Motion in Point-Light Actions
Davila, Alex; Schouten, Ben; Verfaillie, Karl
2014-01-01
Human observers are able to perceive the motion direction of actions (either forward or backward) on the basis of the articulatory, relative motion of the limbs, even when the actions are shown under point-light conditions. However, most studies have focused on the action of walking. The primary purpose of the present study is to further investigate the perception of articulatory motion in different point-light actions (walking, crawling, hand walking, and rowing). On each trial, participants were presented with a forward or backward moving person and they had to decide on the direction of articulatory motion of the person. We analyzed sensitivity (d') as well as response bias (c). In addition to the type of action, the diagnosticity of the available information was manipulated by varying the visibility of the body parts (full body, only upper limbs, or only lower limbs) and the viewpoint from which the action was seen (from frontal view to sagittal view). We observe that, depending on the specific action, perception of direction of motion is driven by different body parts. Implications for the possible existence of a life detector, i.e., an evolutionarily old and innate visual filter that is tuned to quickly and automatically detect the presence of a moving living organism and direct attention to it, are discussed. PMID:25526397
BECHTEL NEVADA; U.S. DEPARTMENT OF ENERGY, NATIONAL NUCLEAR SECURITY ADMINISTRATION NEVADA SITE OFFICE
2005-08-01
Corrective Action Unit (CAU) 516, Septic Systems and Discharge Points, is listed in the ''Federal Facility Agreement and Consent Order'' (FFACO) of 1996 (FFACO, 1996). CAU 516 consists of six Corrective Action Sites (CASs) located in Areas 3, 6, and 22 of the Nevada Test Site (NTS), which is located approximately 65 miles northwest of Las Vegas, Nevada (Figure 1). CAU 516 is comprised of the following six CASs: (1) 03-59-01 Building 3C-36 Septic System; (2) 03-59-02 Building 3C-45 Septic System; (3) 06-51-01 Sump and Piping; (4) 06-51-02 Clay Pipe and Debris; (5) 06-51-03 Clean-Out Box and Piping; and (6) 22-19-04 Vehicle Decontamination Area. Details on site history and site characterization results for CAU 516 are provided in the approved Corrective Action Investigation Plan (CAIP), (U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office [NNSA/NSO], 2003), and the approved Corrective Action Decision Document (CADD) (NNSA/NSO, 2004).
Pointing losses in single-axis and fixed-mount earth-station antennas due to satellite movement
NASA Astrophysics Data System (ADS)
Buchsbaum, L. M.
1986-06-01
There are substantial cost advantages in the use of single-axis or fixed-mount earth-station antennas, thus reducing or eliminating the need for autotracking in earth-stations operating with quasi-stationary satellites. Such cost advantages are more relevant in small antennas where the tracking system represents a larger percentage of the overall cost. In addition, small antennas are particularly suitable to be operated without autotracking, owing to their wider half-power beamwidth. This paper describes a model for calculating the antenna pointing loss as a function of the antenna diameter, operating frequency band, satellite station-keeping tolerances, and the relative geometry between the earth-station and the satellite. The model has been extensively used in the development of Intelsat's IBS and VISTA services as well as in domestic leases. Although the model has been developed based on orbital mechanics equations, its emphasis is towards earth-station and systems engineering applications. Some example calculations and results obtained through an HP-41 CV programmable calculator are also provided.
"Raising the Point!": An Artistic Approach in Supporting a Community's Call to Action
ERIC Educational Resources Information Center
Mendez, Jason
2013-01-01
This article discusses the notion of action and personal agency. The author discusses his experiences constructing an arts installation that supported a grassroots effort to revitalize Hunts Point, a community in the South Bronx that is home to 11,000 families, eighteen waste transfer stations, 40% of New York City's sewage, all of the…
Optical fixing the positions of the off-shore objects applying the method of two reference points
NASA Astrophysics Data System (ADS)
Naus, Krzysztof; Szulc, Dariusz
2014-06-01
The Paper presents the optical method of fixing the off-shore objects positions from the land. The method is based on application of two reference points, having the geographical coordinates defined. The first point was situated high on the sea shore, where also the camera was installed. The second point was intended for use to determine the topocentric horizon plane and it was situated at the water-level. The first section of the Paper contains the definition of space and disposed therein reference systems: connected with the Earth, water-level and the camera system. The second section of the Paper provides a description of the survey system model and the principles of the Charge Coupled Device - CCD array pixel's coordinates (plate coordinates) transformation into the geographic coordinates located on the water-level. In the final section there are presented the general rules of using the worked out method in the optical system. W artykule przedstawiono optyczną metodę wyznaczania pozycji obiektów nawodnych z lądu. Oparto ją na dwóch punktach odniesienia o znanych współrzędnych geograficznych. Pierwszy umiejscowiono wysoko na brzegu morza i przeznaczono do zamontowania kamery. Drugi przeznaczono do określania płaszczyzny horyzontu topocentrycznego i umiejscowiono na poziomie lustra wody. W pierwszej części artykułu zdefi niowano przestrzeń i rozmieszczone w niej układy odniesienia: związany z Ziemią, poziomem lustra wody i kamerą. Drugą część artykułu stanowi opis modelu układu pomiarowego oraz zasad transformacji współrzędnych piksela (tłowych) z matrycy CCD na współrzędne geograficzne punktu umiejscowionego na poziomie lustra wody. W części końcowej zaprezentowano ogólne zasady wykorzystywania opracowanej metody w systemie optycznym.
NASA Astrophysics Data System (ADS)
McEvoy, H. C.; Sadli, M.; Bourson, F.; Briaudeau, S.; Rougié, B.
2013-12-01
The silver and copper fixed-point blackbody sources of NPL were directly compared with those of LNE-Cnam using an IKE LP3 and an IKE LP5 at three wavelengths (650 nm, 795 nm and 903 nm). The two silver fixed points and the two copper fixed points were in excellent agreement with each other, with a difference of 11 mK for the silver and within 16 mK for the copper, with an expanded measurement uncertainty of between 10 mK and 20 mK depending on the pyrometer used. The temperature interval between the silver and copper freezing points was also measured using combinations of all four fixed points. The results with the NPL LP3 gave a value for the silver-copper temperature interval of 122.89 °C with an expanded uncertainty of 30 mK those with the LNE-Cnam LP5 gave a temperature interval of 122.87 °C also with an expanded uncertainty of 30 mK this compares with the ITS-90 value of 122.84 °C.
NASA Astrophysics Data System (ADS)
Head, D. I.; Gray, J.; de Podesta, M.
2009-02-01
Ongoing work to improve the uniformity of vertically mounted furnaces, manufactured by Carbolite (e.g., Type TZF12/75—three-zone furnace capable of 1200 °C, with 75 mm inner bore) along the axis and across the working tube and/or equalizing block is reported. This involves adjusting the size of the end zones, the position of the control thermometers, and the use of cascade-control methods. Means regularly used at NPL to reduce electrical noise in some commercially available ac furnaces through a reduction in the voltage used to “fire” the heaters, and better use of thyristor controllers (by extending their cycle time) are described. The need to shield the controllers from local magnetic fields is described. With these measures, the electrical noise from ac furnaces can approach that of dc furnaces, without the large cost of a dc power supply. The application of new data analysis techniques (Allan deviation) will be shown to improve the representation of uninterrupted fixed-point traces (as used in ingot verification rather than PRT calibration). Reduction of statistical noise on the temperature measurements has been achieved for data on the freezing plateau by determining the statistically optimum averaging time. This shows that the statistical uncertainty in the determination of the temperature of a particular freezing plateau is less than 25 μK and that noise (drift) from other sources, possibly due to variations in room temperature, starts to become appreciable over periods longer than a few tens of minutes. The measurement of freezing and melting plateaux at this level is aided by the introduction of new ASL-F900 bridge(s), and quieter/larger standard resistor baths.
Friedman, Adam; Waite, Kim; Brandt, Staci; Meckfessel, Matthew H
2016-02-01
Nonadherence to topical acne therapies is a major contributing factor to poor treatment outcomes. Multiple contributing factors have been identified, including a lack of perceived efficacy and fear of side effects. A fixed-dose combination gel of adapalene/benzoyl peroxide gel, 0.1%/2.5% (A-BPO) is an efficacious and safe treatment for a range of acne severities in patients as young as 9 years old. A meta-analysis of 14 clinical studies involving A-BPO was conducted to assess the 4 week efficacy and overall tolerability of this treatment. Over 2,300 subjects were included in the analysis. Mean total, inflammatory, and non-inflammatory lesion counts decreased at 4 weeks by 40.8%, 46.2%, and 37.5%, respectively. Worst post-baseline tolerability scores for stinging/burning, dryness, scaling, and erythema were none or mild for a majority of subjects. The result of this meta-analysis add to the body of literature supporting the use of A-BPO in a variety of acne patients and shows that A-BPO provides meaningful clinical results within 4 weeks and will be well-tolerated for a majority of patients. With a demonstrable quick onset of action and high tolerability, A-BPO may improve adherence, and ultimately treatment outcomes, by addressing factors that contribute to nonadherence.
J Drugs Dermatol. 2016;15(2):231-236. PMID:26885793
ERIC Educational Resources Information Center
Bellver-Cebreros, Consuelo; Rodriguez-Danta, Marcelo
2009-01-01
An apparently unnoticed analogy between the torque-free motion of a rotating rigid body about a fixed point and the propagation of light in anisotropic media is stated. First, a new plane construction for visualizing this torque-free motion is proposed. This method uses an intrinsic representation alternative to angular momentum and independent of…
ERIC Educational Resources Information Center
Bellver-Cebreros, Consuelo; Rodriguez-Danta, Marcelo
2009-01-01
An apparently unnoticed analogy between the torque-free motion of a rotating rigid body about a fixed point and the propagation of light in anisotropic media is stated. First, a new plane construction for visualizing this torque-free motion is proposed. This method uses an intrinsic representation alternative to angular momentum and independent of
Referral of tactile stimuli to action points in virtual reality with reaction force.
Moizumi, Shunjiro; Yamamoto, Shinya; Kitazawa, Shigeru
2007-09-01
When we touch something with a tool, we feel the touch at the tip of the tool rather than at the hand. Yamamoto and Kitazawa [Yamamoto, S., Kitazawa, S., 2001b. Sensation at the tips of invisible tools. Nat. Neurosci. 4, 979-980] previously showed that the judgment of the temporal order of two successive stimuli, delivered to the tips of sticks held in each hand, was dramatically altered by crossing the sticks without changing the positions of the hands. This provided evidence for the referral of tactile signals to the tip of a tool in hand. In this study, we examined importance of force feedback from the tool in the referral by manipulating the direction of force feedback in a virtual reality. The virtual tool consisted of a spherical action point that was moved with a stylus in hand. Subjects held two styli, one in each hand, put each action point on each of two buttons in the virtual reality, and were required to judge the order of successive taps, delivered to the two styli. We manipulated the direction of reaction force from each button so that it was congruent or incongruent to the visual configuration of the button. When the arms were uncrossed, judgment primarily depended on whether the action points were crossed or not in the visual space. But when the arms were crossed, judgment critically depended on the direction of force feedback. The results show that tactile signals can be referred to the action point in the virtual reality and that the force feedback becomes a critical factor when the arms are crossed. PMID:17617482
Grant Evenson
2007-02-01
Corrective Action Unit (CAU) 556, Dry Wells and Surface Release Points, is located in Areas 6 and 25 of the Nevada Test Site, 65 miles northwest of Las Vegas, Nevada. Corrective Action Unit 556 is comprised of four corrective action sites (CASs) listed below: •06-20-04, National Cementers Dry Well •06-99-09, Birdwell Test Hole •25-60-03, E-MAD Stormwater Discharge and Piping •25-64-01, Vehicle Washdown and Drainage Pit These sites are being investigated because existing information on the nature and extent of potential contamination is insufficient to evaluate and recommend corrective action alternatives. Additional information will be obtained by conducting a corrective action investigation before evaluating corrective action alternatives and selecting the appropriate corrective action for each CAS. The results of the field investigation will support a defensible evaluation of viable corrective action alternatives that will be presented in the Corrective Action Decision Document.
Closure Report for Corrective Action Unit 516: Septic Systems and Discharge Points
NSTec Environmental Restoration
2007-02-01
Corrective Action Unit (CAU) 516 is located in Areas 3, 6, and 22 of the Nevada Test Site. CAU 516 is listed in the Federal Facility Agreement and Consent Order of 1996 as Septic Systems and Discharge Points, and is comprised of six Corrective Action Sites (CASs): {sm_bullet} CAS 03-59-01, Bldg 3C-36 Septic System {sm_bullet} CAS 03-59-02, Bldg 3C-45 Septic System {sm_bullet} CAS 06-51-01, Sump and Piping {sm_bullet} CAS 06-51-02, Clay Pipe and Debris {sm_bullet} CAS 06-51-03, Clean Out Box and Piping {sm_bullet} CAS 22-19-04, Vehicle Decontamination Area The Nevada Division of Environmental Protection (NDEP)-approved corrective action alternative for CASs 06-51-02 and 22-19-04 is no further action. The NDEP-approved corrective action alternative for CASs 03-59-01, 03-59-02, 06-51-01, and 06-51-03 is clean closure. Closure activities included removing and disposing of total petroleum hydrocarbon (TPH)-impacted septic tank contents, septic tanks, distribution/clean out boxes, and piping. CAU 516 was closed in accordance with the NDEP-approved CAU 516 Corrective Action Plan (CAP). The closure activities specified in the CAP were based on the recommendations presented in the CAU 516 Corrective Action Decision Document (U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office, 2004). This Closure Report documents CAU 516 closure activities. During closure activities, approximately 186 tons of hydrocarbon waste in the form of TPH-impacted soil and debris, as well as 89 tons of construction debris, were generated and managed and disposed of appropriately. Waste minimization techniques, such as field screening of soil samples and the utilization of laboratory analysis to characterize and classify waste streams, were employed during the performance of closure work.
La, Moonwoo; Park, Sang Min; Kim, Dong Sung
2015-01-01
In this study, a multiple sample dispenser for precisely metered fixed volumes was successfully designed, fabricated, and fully characterized on a plastic centrifugal lab-on-a-disk (LOD) for parallel biochemical single-end-point assays. The dispenser, namely, a centrifugal multiplexing fixed-volume dispenser (C-MUFID) was designed with microfluidic structures based on the theoretical modeling about a centrifugal circumferential filling flow. The designed LODs were fabricated with a polystyrene substrate through micromachining and they were thermally bonded with a flat substrate. Furthermore, six parallel metering and dispensing assays were conducted at the same fixed-volume (1.27 μl) with a relative variation of ±0.02 μl. Moreover, the samples were metered and dispensed at different sub-volumes. To visualize the metering and dispensing performances, the C-MUFID was integrated with a serpentine micromixer during parallel centrifugal mixing tests. Parallel biochemical single-end-point assays were successfully conducted on the developed LOD using a standard serum with albumin, glucose, and total protein reagents. The developed LOD could be widely applied to various biochemical single-end-point assays which require different volume ratios of the sample and reagent by controlling the design of the C-MUFID. The proposed LOD is feasible for point-of-care diagnostics because of its mass-producible structures, reliable metering/dispensing performance, and parallel biochemical single-end-point assays, which can identify numerous biochemical. PMID:25610516
Brückner, Hans-Peter; Spindeldreier, Christian; Blume, Holger
2013-01-01
A common approach for high accuracy sensor fusion based on 9D inertial measurement unit data is Kalman filtering. State of the art floating-point filter algorithms differ in their computational complexity nevertheless, real-time operation on a low-power microcontroller at high sampling rates is not possible. This work presents algorithmic modifications to reduce the computational demands of a two-step minimum order Kalman filter. Furthermore, the required bit-width of a fixed-point filter version is explored. For evaluation real-world data captured using an Xsens MTx inertial sensor is used. Changes in computational latency and orientation estimation accuracy due to the proposed algorithmic modifications and fixed-point number representation are evaluated in detail on a variety of processing platforms enabling on-board processing on wearable sensor platforms. PMID:24110597
Shimamoto, Akira; Yamashita, Keitaro; Inoue, Hirofumi; Yang, Sung-Mo; Iwata, Masahiro; Ike, Natsuko
2013-04-01
Destructive tests are generally applied to evaluate the fixed strength of spot-welding nuggets of zinc-plated steel (which is a widely used primary structural material for automobiles). These destructive tests, however, are expensive and time-consuming. This paper proposes a nondestructive method for evaluating the fixed strength of the welded joints using surface electrical resistance. A direct current nugget-tester and probes have been developed by the authors for this purpose. The proposed nondestructive method uses the relative decrease in surface electrical resistance, α. The proposed method also considers the effect of the corona bond. The nugget diameter is estimated by two factors: R Quota, which is calculated from variation of resistance, and a constant that represents the area of the corona bond. Since the maximum tensile strength is correlated with the nugget diameter, it can be inferred from the estimated nugget diameter. When appropriate measuring conditions for the surface electrical resistance are chosen, the proposed method can effectively evaluate the fixed strength of the spot-welded joints even if the steel sheet is zinc-plated. PMID:24891747
1998-06-01
This Corrective Action Decision Document has been prepared for the Area 3 Building 03-60 Underground Discharge Point (Corrective Action Unit 423) in accordance with the Federal Facility Agreement and Consent Order of 1996 (FFACO, 1996). Corrective Action Unit 423 is located at the Tonopah Test Range and is comprised of Corrective Action Site 03-02-002-0308. The purpose of this Corrective Action Decision Document is to identify and provide a rationale for the selection of a recommended corrective action alternative for Corrective Action Unit 423. The scope of this Correction Action Decision Document consists of the following: � Develop corrective action objectives. � Identify corrective action alternative screening criteria. � Develop corrective action alternatives. � Perform detailed and comparative evaluations of the corrective action alternatives in relation to the corrective action objectives and screening criteria. � Recommend and justify a preferred corrective action alternative for the Corrective Action Unit. In January 1998, a corrective action investigation was performed as set forth in the Corrective Action Investigation Plan for Corrective Action Unit No. 423: Building 03-60 Underground Discharge Point, Tonopah Test Range, Nevada (DOE/NV, 1997). A hydrocarbon plume was found to emanate from near the bottom of the Underground Discharge Point to the west. The plume encompasses approximately 65 square meters (700 square feet). The highest total petroleum hydrocarbon level detected was 2,400 milligrams per kilogram. No other contaminants were detected above preliminary action levels. Details of the investigation can be found in Appendix A of this document. Based on the potential exposure pathways identified during the Data Quality Objectives process, the following corrective action objectives have been identified for Corrective Action Unit 423: � Prevent or mitigate human exposure to subsurface soil containing contaminants of concern. � Prevent adverse impacts to groundwater quality. Based on the review of existing data, future land use assumption, and current operations at the Tonopah Test Range, the following alternatives were developed for consideration at the Building 03-60 Underground Discharge Point: � Alternative 1 - No Action � Alternative 2 - Closure in Place with Administrative Controls � Alternative 3 - Partial Excavation, Disposal, and Administrative Controls � Alternative 4 - In Situ Bioremediation The corrective action alternatives were evaluated based on four general corrective action standards and five remedy selection decision factors. Based on the results of this evaluation, the preferred alternative for Corrective Action Unit 423 is Alternative 2, Closure in Place with Administrative Controls. The preferred corrective action alternative was evaluated on technical merit, focusing on performance, reliability, feasibility, and safety. The alternative was judged to meet all requirements for the technical components evaluated. The alternative also meets all applicable state and federal regulations for closure of the site and will reduce potential future exposure pathways to the contaminated soils.
Lundberg, Jonas; Rollenhagen, Carl; Hollnagel, Erik
2010-11-01
In accident investigation, the ideal is often to follow the principle "what-you-find-is-what-you-fix", an ideal reflecting that the investigation should be a rational process of first identifying causes, and then implement remedial actions to fix them. Previous research has however identified cognitive and political biases leading away from this ideal. Somewhat surprisingly, however, the same factors that often are highlighted in modern accident models are not perceived in a recursive manner to reflect how they influence the process of accident investigation in itself. Those factors are more extensive than the cognitive and political biases that are often highlighted in theory. Our purpose in this study was to reveal constraints affecting accident investigation practices that lead the investigation towards or away from the ideal of "what-you-find-is-what-you-fix". We conducted a qualitative interview study with 22 accident investigators from different domains in Sweden. We found a wide range of factors that led investigations away from the ideal, most which more resembled factors involved in organizational accidents, rather than reflecting flawed thinking. One particular limitation of investigation was that many investigations stop the analysis at the level of "preventable causes", the level where remedies that were currently practical to implement could be found. This could potentially limit the usefulness of using investigations to get a view on the "big picture" of causes of accidents as a basis for further remedial actions. PMID:20728672
Caggiano, Vittorio; Giese, Martin; Thier, Peter; Casile, Antonino
2015-02-01
The discovery of mirror neurons compellingly shows that the monkey premotor area F5 is active not only during the execution but also during the observation of goal-directed motor acts. Previous studies have addressed the functioning of the mirror-neuron system at the single-unit level. Here, we tackled this research question at the network level by analysing local field potentials in area F5 while the monkey was presented with goal-directed actions executed by a human or monkey actor and observed either from a first-person or third-person perspective. Our analysis showed that rhythmic responses are not only present in area F5 during action observation, but are also modulated by the point of view. Observing an action from a subjective point of view produced significantly higher power in the low-frequency band (2-10 Hz) than observing the same action from a frontal view. Interestingly, an increase in power in the 2-10 Hz band was also produced by the execution of goal-directed motor acts. Independently of the point of view, action observation also produced a significant decrease in power in the 15-40 Hz band and an increase in the 60-100 Hz band. These results suggest that, depending on the point of view, action observation might activate different processes in area F5. Furthermore, they may provide information about the functional architecture of action perception in primates. PMID:25442357
ERIC Educational Resources Information Center
Gillberg, Claudia
2011-01-01
Against the background of Swedish preschool's historical and traditional functions in Swedish society, this article focuses on some of the choice points and their implications for professional and organisational development in preschool. By combining feminist pragmatism and feminist action research, some analytical points are made regarding the…
NASA Astrophysics Data System (ADS)
Nieto, John
2007-04-01
Since their introduction in 1993, turbo codes have received a significant amount of attention in the communications theory field due to their Shannon-capacity approaching performance. In recent years, the cellular systems market has embraced turbo code technology and made it part of the latest standards. This paper will review the effects of scale factors, fixed-point precision, soft decisions and hard decisions on the performance of the turbo codes defined in the UMTS third-generation cellular system. In addition, a new scale factor estimation technique which provides improved performance at low signal to noise ratios will be presented.
US DOE Nevada Operations Office
1999-06-30
This Record of Technical Change provides updates to the technical information included in ''Corrective Action Investigation Plan for Corrective Action Unit 406: Area 3 Building 03-74 and Building 03-58 Underground Discharge Points and Corrective Action Unit 429: Area 3 Building 03-55 and Area 9 Building 09-52 Underground Discharge Points, Tonopah Test Range, Nevada'' Revision 0
Ghez, Claude; Asnani, Supriya
2011-01-01
We examined elbow muscle activities and movement kinematics to determine how subjects combine elementary control actions in performing movements with one and two trajectory segments. In reaching, subjects made a rapid elbow flexion to a visual target before stabilizing the limb with either a low or a higher level of elbow flexor/extensor coactivity (CoA), which was cued by target diameter. Cursor diameter provided real-time biofeedback of actual muscle CoA. In reversing, the limb was to reverse direction within the target and return to the origin with minimal CoA. We previously reported that subjects overshoot the goal when attempting a reversal after first having learned to reach accurately to the same target. Here we test the hypothesis that this hypermetria results because reversals co-opt the initial feedforward control action from the preceding trained reach, thereby failing to account for task-dependent changes in limb impedance induced by differences in flexor/extensor coactivity as the target is acquired (higher in reaching than reversing). Instructed increases in elbow CoA began mid-reach, thus increasing elbow impedance and reducing transient oscillations present in low CoA movments. Flexor EMG alone increased at movement onset. Test reversals incorporated the initial agonist activity of previous reaches but not the increased coactivity at the target, thus leading to overshoot. Moreover, we observed elevated coactivity in reversals upon returning to the origin even though coactivity in reaching was centered at the goal target. These findings refute the idea that the brain necessarily invokes distinct unitary control actions for reaches and reversals made to the same target. Instead, reaches and reversals share a common control action that initiates trajectories toward their target and another later control action that terminates movement and stabilizes the limb about its final resting posture, which differs in the two tasks. PMID:21849613
Scheidt, Robert A; Ghez, Claude; Asnani, Supriya
2011-11-01
We examined elbow muscle activities and movement kinematics to determine how subjects combine elementary control actions in performing movements with one and two trajectory segments. In reaching, subjects made a rapid elbow flexion to a visual target before stabilizing the limb with either a low or a higher level of elbow flexor/extensor coactivity (CoA), which was cued by target diameter. Cursor diameter provided real-time biofeedback of actual muscle CoA. In reversing, the limb was to reverse direction within the target and return to the origin with minimal CoA. We previously reported that subjects overshoot the goal when attempting a reversal after first having learned to reach accurately to the same target. Here we test the hypothesis that this hypermetria results because reversals co-opt the initial feedforward control action from the preceding trained reach, thereby failing to account for task-dependent changes in limb impedance induced by differences in flexor/extensor coactivity as the target is acquired (higher in reaching than reversing). Instructed increases in elbow CoA began mid-reach, thus increasing elbow impedance and reducing transient oscillations present in low CoA movments. Flexor EMG alone increased at movement onset. Test reversals incorporated the initial agonist activity of previous reaches but not the increased coactivity at the target, thus leading to overshoot. Moreover, we observed elevated coactivity in reversals upon returning to the origin even though coactivity in reaching was centered at the goal target. These findings refute the idea that the brain necessarily invokes distinct unitary control actions for reaches and reversals made to the same target. Instead, reaches and reversals share a common control action that initiates trajectories toward their target and another later control action that terminates movement and stabilizes the limb about its final resting posture, which differs in the two tasks. PMID:21849613
U.S. Department of Energy , National Nuclear Security Administration Nevada Sites Office
2003-04-28
This Corrective Action Investigation Plan (CAIP) contains the U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Sites Office's (NNSA/NSO's) approach to collect the data necessary to evaluate corrective action alternatives appropriate for the closure of Corrective Action Unit (CAU) 516, Septic Systems and Discharge Points, Nevada Test Site (NTS), Nevada, under the Federal Facility Agreement and Consent Order. CAU 516 consists of six Corrective Action Sites: 03-59-01, Building 3C-36 Septic System; 03-59-02, Building 3C-45 Septic System; 06-51-01, Sump Piping, 06-51-02, Clay Pipe and Debris; 06-51-03, Clean Out Box and Piping; and 22-19-04, Vehicle Decontamination Area. Located in Areas 3, 6, and 22 of the NTS, CAU 516 is being investigated because disposed waste may be present without appropriate controls, and hazardous and/or radioactive constituents may be present or migrating at concentrations and locations that could potentially pose a threat to human health and the environment. Existing information and process knowledge on the expected nature and extent of contamination of CAU 516 are insufficient to select preferred corrective action alternatives; therefore, additional information will be obtained by conducting a corrective action investigation. The results of this field investigation will support a defensible evaluation of corrective action alternatives in the corrective action decision document. Record of Technical Change No. 1 is dated 3/2004.
NASA Astrophysics Data System (ADS)
Lowe, Dave; Kodwani, Darsh
2015-11-01
Re-calibration of a thermocouple after it has been installed in a process is often not practical. In situ monitoring of performance is desirable and can be done with built-in reference standards based on melting or freezing phase transitions. Binary alloys with a monotectic reaction frequently have two invariant melt/freeze phase transitions taking place in the same material over a range of compositions. This makes them potentially well suited to be in situ temperature calibration artifacts, enabling correction for thermocouple drift without the need to disturb the thermocouple. A zinc-bismuth fixed-point cell was constructed and has been shown to be stable with two well-defined melting plateaus at nominally 255°C and 415°C. Two miniature fixed-point cells (each designed to be permanently installed with a thermocouple) based on zinc-bismuth and aluminum-indium alloys were made. Measurements have shown that the phase transitions can be identified despite the small quantity of metals used and that the alloys were sufficiently stable to have the potential to provide improved long-term confidence in process control and monitoring.
1997-10-27
This Corrective Action Investigation Plan (CAIP) contains the environmental sample collection objectives and the criteria for conducting site investigation activities at Corrective Action Unit (CAU) Number 423, the Building 03-60 Underground Discharge Point (UDP), which is located in Area 3 at the Tonopah Test Range (TTR). The TTR, part of the Nellis Air Force Range, is approximately 225 kilometers (140 miles) northwest of Las Vegas, Nevada. CAU Number 423 is comprised of only one Corrective Action Site (CAS) which includes the Building 03-60 UDP and an associated discharge line extending from Building 03-60 to a point approximately 73 meters (240 feet) northwest. The UDP was used between approximately 1965 and 1990 to dispose of waste fluids from the Building 03-60 automotive maintenance shop. It is likely that soils surrounding the UDP have been impacted by oil, grease, cleaning supplies and solvents as well as waste motor oil and other automotive fluids released from the UDP.
DOE /NV
1997-10-01
This Corrective Action Investigation Plan (CAIP) has been developed in accordance with the Federal Facility Agreement and Consent Order (FFACO) that was agreed to by the US Department of Energy, Nevada Operations Office (DOE/NV), the State of Nevada Division of Environmental Protection (NDEP), and the US Department of Defense. The CAIP is a document that provides or references all of the specific information for investigation activities associated with Corrective Action Units (CAUS) or Corrective Action Sites (CASs) (FFACO, 1996). As per the FFACO (1996), CASs are sites potentially requiring corrective action(s) and may include solid waste management units or individual disposal or release sites. Corrective Action Units consist of one or more CASs grouped together based on geography, technical similarity, or agency responsibility for the purpose of determining corrective actions. This CAIP contains the environmental sample collection objectives and the criteria for conducting site investigation activities at CAU No. 423, the Building 03-60 Underground Discharge Point (UDP), which is located in Area 3 at the Tonopah Test Range (TTR). The TTR, part of the Nellis Air Force Range, is approximately 225 kilometers (km) (140 miles [mi]) northwest of Las Vegas, Nevada (Figures 1-1 and 1-2). Corrective Action Unit No. 423 is comprised of only one CAS (No. 03-02-002-0308), which includes the Building 03-60 UDP and an associated discharge line extending from Building 03-60 to a point approximately 73 meters (m) (240 feet [ft]) northwest as shown on Figure 1-3.
Determination of the sinking and terminating points of action unit on humanoid skull through GFEAD
NASA Astrophysics Data System (ADS)
Tadesse, Yonas; Priya, Shashank
2011-04-01
This study describes modeling and computational analysis technique for design of humanoid head that can generate human-like facial expression. Current humanoid prototypes utilize either traditional servo motors or other form of bulky actuators such as air muscles to deform soft elastomeric skin that in turn creates facial expression. However, these prior methods have inherent drawbacks and do not resemble human musculature. In this paper, we report the advances made in design of humanoid head using shape memory alloy actuators. These muscle-like actuators are often in discrete form and finite in number. This brings up the fundamental question regarding their arrangement and location of terminating and sinking points for each action unit. We address this question by developing a Graphical Facial Expression Analysis and Design (GFEAD) technique that can be used to optimize the space, analyze the deformation behavior, and determine the effect of actuator properties. GFEAD will be described through generic mathematical models and analytical geometry confining the discussion to two-dimensional planes. The implementation of the graphical method will be presented by considering different practical cases.
Alfred N. Wickline
2004-04-01
This Corrective Action Decision Document (CADD) has been prepared for Corrective Action Unit (CAU) 516, Septic Systems and Discharge Points, Nevada Test Site, Nevada, in accordance with the ''Federal Facility Agreement and Consent Order'' (1996). Corrective Action Unit 516 is comprised of the following Corrective Action Sites (CASs): (1) 03-59-01 - Bldg 3C-36 Septic System; (2) 03-59-02 - Bldg 3C-45 Septic System; (3) 06-51-01 - Sump and Piping; (4) 06-51-02 - Clay Pipe and Debris; (5) 06-51-03 - Clean Out Box and Piping; and (7) 22-19-04 - Vehicle Decontamination Area. The purpose of this CADD is to identify and provide the rationale for the recommendation of an acceptable corrective action alternative for each CAS within CAU 516. Corrective action investigation activities were performed between July 22 and August 14, 2003, as set forth in the Corrective Action Investigation Plan. Supplemental sampling was conducted in late 2003 and early 2004.
NASA Astrophysics Data System (ADS)
Geng, J.; Bock, Y.; Fang, P.; Haase, J. S.
2012-12-01
The development of single-receiver integer ambiguity resolution in recent years has made the GPS precise point positioning (PPP) technique a valuable tool in measuring centimeter-level displacements epoch by epoch at a single station. A good application for this technique is identifying ground motions in an earthquake and tsunami early warning system. With a single receiver, PPP with ambiguity resolution can reproduce the positioning accuracy of conventional differential positioning techniques, but does not depend on any nearby reference stations which may also be displaced during an earthquake. As a result, the PPP data processing is more straightforward and efficient, suggesting that onsite displacement estimation can be carried out semi-autonomously at each GPS station and only a small amount of data, i.e. 3D displacements rather than raw measurements in the differential positioning, need to be transmitted to warning centers. Due to these merits and as part of a NASA-sponsored research effort, we have developed an operational real-time PPP system for Western North America, a vast region of tectonic deformation and significant seismic risk. A group of about 75 real-time GPS stations throughout North America and located far from western US coast (>300 km) is employed to estimate satellite-specific corrections (i.e. satellite clocks and fractional-cycle biases) with the predicted satellite orbits provided by the IGS (International GNSS Services). We note that our PPP implementation is challenged by geophysical constraints in North America and so all clients in the zone of deformation are outside the coverage of the reference network, and thus measurement errors originating in the atmosphere, satellite orbits and clocks are less correlated between the reference stations and the PPP clients. Despite this difficulty, the horizontal positioning accuracy at each PPP station is around 1 cm while the vertical better than 5 cm. This accuracy is sufficient to optimally combine the 1-Hz PPP-derived displacements with collocated (100 Hz) accelerometer data using a Kalman filter to estimate total displacement waveforms with millimeter-level accuracy. We also report on the testing of our approach in a simulated real-time environment for the 2006 Mw 6.0 Parkfield and 2010 Mw 7.2 El Mayor-Cucapah earthquakes.
Action and emotion recognition from point light displays: an investigation of gender differences.
Alaerts, Kaat; Nackaerts, Evelien; Meyns, Pieter; Swinnen, Stephan P; Wenderoth, Nicole
2011-01-01
Folk psychology advocates the existence of gender differences in socio-cognitive functions such as 'reading' the mental states of others or discerning subtle differences in body-language. A female advantage has been demonstrated for emotion recognition from facial expressions, but virtually nothing is known about gender differences in recognizing bodily stimuli or body language. The aim of the present study was to investigate potential gender differences in a series of tasks, involving the recognition of distinct features from point light displays (PLDs) depicting bodily movements of a male and female actor. Although recognition scores were considerably high at the overall group level, female participants were more accurate than males in recognizing the depicted actions from PLDs. Response times were significantly higher for males compared to females on PLD recognition tasks involving (i) the general recognition of 'biological motion' versus 'non-biological' (or 'scrambled' motion); or (ii) the recognition of the 'emotional state' of the PLD-figures. No gender differences were revealed for a control test (involving the identification of a color change in one of the dots) and for recognizing the gender of the PLD-figure. In addition, previous findings of a female advantage on a facial emotion recognition test (the 'Reading the Mind in the Eyes Test' (Baron-Cohen, 2001)) were replicated in this study. Interestingly, a strong correlation was revealed between emotion recognition from bodily PLDs versus facial cues. This relationship indicates that inter-individual or gender-dependent differences in recognizing emotions are relatively generalized across facial and bodily emotion perception. Moreover, the tight correlation between a subject's ability to discern subtle emotional cues from PLDs and the subject's ability to basically discriminate biological from non-biological motion provides indications that differences in emotion recognition may - at least to some degree - be related to more basic differences in processing biological motion per se. PMID:21695266
NASA Astrophysics Data System (ADS)
Oppermann, R.; Schmidt, M. J.
2008-12-01
A scaling theory of replica symmetry breaking (RSB) in the Sherrington-Kirkpatrick (SK) model is presented in the framework of critical phenomena for the scaling regime of large RSB orders ? , small temperatures T , and small (homogeneous) magnetic fields H . We employ the pseudodynamical picture [R. Oppermann, M. J. Schmidt, and D. Sherrington, Phys. Rev. Lett. 98, 127201 (2007)], where two critical points CP1 and CP2 are associated with the order functions pseudodynamical limits lima??q(a)=1 and lima?0q(a)=0 at (T=0 , H=0 , 1/?=0) . CP1 - and CP2 -dominated contributions to the free energy functional F[q(a)] require an unconventional scaling hypothesis. We determine the scaling contributions in accordance with detailed numerical self-consistent solutions for up to 200 orders of RSB. Power laws, scaling functions, and crossover lines are obtained. CP1 -dominated behavior is found for the nonequilibrium susceptibility, which decays like ?1=?-5/3f1(T/?-5/3) , for the entropy, which obeys S(T=0)?12 , and for the subclass of diverging parameters ai=?5/3fai(T/?-5/3) [describing Parisi box sizes mi(T)?ai(T)T ], with f1(?)? and fai(?)1/? for ??? , while f(0) is finite. CP2 -dominated behavior, controlled by the magnetic field H while temperature is irrelevant, is retrieved in the plateau height (or width) of the order function q(a) according to qpl(H)=?-1fpl(H2/3/?-1) with fpl?(?)????? and fpl(0) finite. Divergent characteristic RSB orders ?CP1(T)T-3/5 and ?CP2(H)H-2/3 , respectively, describe the crossover from mean field SK- to RSB-critical behavior with rational-valued exponents extracted with high precision from our RSB data. The order function q(a) is obtained as a fixed-point function q*(a*) of RSB flow, in agreement with integrated fixed-point energy and susceptibility distributions.
Grant Evenson
2008-09-01
This Corrective Action Decision Document (CADD)/Closure Report (CR) has been prepared for Corrective Action Unit 556, Dry Wells and Surface Release Points, located at the Nevada Test Site, Nevada, in accordance with the Federal Facility Agreement and Consent Order (FFACO, 1996; as amended February 2008). Corrective Action Unit (CAU) 556 is comprised of four corrective action sites (CASs): • 06-20-04, National Cementers Dry Well • 06-99-09, Birdwell Test Hole • 25-60-03, E-MAD Stormwater Discharge and Piping • 25-64-01, Vehicle Washdown and Drainage Pit The purpose of this CADD/CR is to provide justification and documentation supporting the recommendation for closure of CAU 556 with no further corrective action. To achieve this, corrective action investigation (CAI) activities began on February 7 and were completed on June 19, 2008, as set forth in the Corrective Action Investigation Plan for Corrective Action Unit 556: Dry Wells and Surface Release Points, Nevada Test Site, Nevada (NNSA/NSO, 2007). The purpose of the CAI was to fulfill the following data needs as defined during the data quality objective (DQO) process: • Determine whether contaminants of concern (COCs) are present. • If COCs are present, determine their nature and extent. • Provide sufficient information and data to complete appropriate corrective actions. The CAU 556 data were evaluated based on the data quality assessment process, which demonstrated the quality and acceptability of the data for use in fulfilling the DQO data needs. Analytes detected during the CAI were evaluated against appropriate final action levels (FALs) to identify the COCs for each CAS. The results of the CAI identified COCs at one of the four CASs in CAU 556 that required the completion of a corrective action. Assessment of the data generated from investigation activities conducted at CAU 556 revealed the following: • Corrective Action Sites 06-20-04, 06-99-09, and 25-64-01 do not contain contamination at concentrations exceeding the FALs. • Polychlorinated biphenyl (PCB) contamination above the FAL was identified in the surface and/or shallow subsurface soils at the outfall and around Catch Basin 2, and in soils contained within the catch basins and the manhole at CAS 25-60-03. A corrective action of close in place with a soil removal action and use restriction (UR) was completed at CAS 25-60-03. The PCB-contaminated soils were removed from the outfall area and around Catch Basin 2, and disposed of at a Nevada Test Site landfill as part of a removal action. The catch basins and the manhole were sealed shut by filling them with grout. The end of the outfall pipe was plugged using grout, covered with soil, and the area was regraded. A UR was applied to the entire stormwater system at CAS 25-60-03, which includes the three catch basins, manhole, and associated piping. No further action is the corrective action for CASs 06-20-04, 06-99-09, and 25-64-01. The liquids in the test holes at CAS 06-99-09 were removed for disposal and the features were filled with grout as a best management practice. The drainage pipe between the vehicle washdown pad and the drainage pit at CAS 25-64-01 was sealed at each end as a best management practice. The corrective actions were evaluated on technical merit focusing on performance, reliability, feasibility, safety, and cost. They were judged to meet all requirements for the technical components evaluated. The corrective actions meet all applicable federal and state regulations for closure of the site and will reduce potential exposure pathways to the contaminated media to an acceptable level at CAU 556. Therefore, the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office provides the following recommendations: • Maintain a UR for the entire stormwater drainage system (i.e., three catch basins, one manhole, and associated piping) at CAS 25-60-03. • No further corrective action for CAU 556. • A Notice of Completion to the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office is requested from the Nevada Division of Environmental Protection for closure of CAU 556. • Corrective Action Unit 556 should be moved from Appendix III to Appendix IV of the Federal Facility Agreement and Consent Order.
NASA Astrophysics Data System (ADS)
Pearce, J. V.; Elliott, C. J.; Lowe, D. H.; Failleau, G.; Deuzé, T.; Bourson, F.; Sadli, M.; Machin, G.
2014-04-01
A series of high-temperature fixed points (HTFPs) Pt-C (1738 , and Ru-C (1953 ) have been constructed at the National Physical Laboratory (NPL) and the Laboratoire National de métrologie et d'Essais and Conservatoire national des arts et métiers (LNE-Cnam). These are required for the calibration of high-temperature thermocouples in the framework of work package 6 of the European Metrology Research Programme IND01 project "HiTeMS." The goal of this work package is to establish a European capability that can determine low-uncertainty reference functions of non-standard high-temperature thermocouples. For reference functions to be widely applicable, measurements must be performed by more than one institute and preferably by more than one method. Due to the high price of the ingot materials, miniature HTFP cells are used. NPL and LNE-Cnam constructed their HTFP cells with different designs; these are described here, together with the performance of the cells using both radiation thermometry and thermocouples. The melting temperature of the Ru-C cells (for thermocouple calibrations) was determined using radiation thermometry at both NPL and LNE-Cnam, and the two results are compared. The suitability of the cells for calibration of W-Re and Rh-Ir thermocouples is evaluated, and some results are presented. Some discussion is given regarding the materials challenges when calibrating Rh-Ir thermocouples up to 2000 C.
NASA Technical Reports Server (NTRS)
Naruse, Y.; Semba, K.; Kiwaki, S.; Mishima, M.
1983-01-01
Isoelectric point changes in suspensions of refractory materials vis-a-vis the role of deflocculants used in monolithic refractories were investigated by considering the mineral compositions and adsorbed ions in four kinds of clay. Three types of curves represented the relation between the isoelectric point and the deflocculant. The surface charge of clay particles in the suspensions became negative as a result of the deflocculant, since the isoelectric point of suspensions decreased as the deflocculant was added. The isoelectric point changes of calcined alumina were also compared with those of the clays, and a similar phenomenon was observed, except that the deflocculant dispersed the calcined alumina better than it did the clays. A simple model was used to analyze the results.
Nonperturbative saddle point for the effective action of disordered and interacting electrons in 2D.
Chamon, C; Mucciolo, E R
2000-12-25
We find a nonperturbative saddle-point solution for the nonlinear sigma model proposed by Finkelstein for interacting and disordered electronic systems. Spin rotation symmetry, present in the original saddle-point solution, is spontaneously broken at one loop, as in the Coleman-Weinberg mechanism. The new solution is singular in both the disorder and triplet interaction strengths, and it also explicitly demonstrates that a nontrivial ferromagnetic state appears in a theory where the disorder average is carried out from the outset. PMID:11136058
Nagai, Satoshi; Hida, Kohsuke; Urushizaki, Shingo; Onitsuka, Goh; Yasuike, Motoshige; Nakamura, Yoji; Fujiwara, Atushi; Tajimi, Seisuke; Kimoto, Katsunori; Kobayashi, Takanori; Gojobori, Takashi; Ototake, Mitsuru
2016-02-01
In this study, we investigated the influence of diurnal sampling bias on the community structure of plankton by comparing the biodiversity among seawater samples (n=9) obtained every 3h for 24h by using massively parallel sequencing (MPS)-based plankton monitoring at a fixed point conducted at Himedo seaport in Yatsushiro Sea, Japan. The number of raw operational taxonomy units (OTUs) and OTUs after re-sampling was 507-658 (558 ± 104, mean ± standard deviation) and 448-544 (467 ± 81), respectively, indicating high plankton biodiversity at the sampling location. The relative abundance of the top 20 OTUs in the samples from Himedo seaport was 48.8-67.7% (58.0 ± 5.8%), and the highest-ranked OTU was Pseudo-nitzschia species (Bacillariophyta) with a relative abundance of 17.3-39.2%, followed by Oithona sp. 1 and Oithona sp. 2 (Arthropoda). During seawater sampling, the semidiurnal tidal current having an amplitude of 0.3ms(-1) was dominant, and the westward residual current driven by the northeasterly wind was continuously observed during the 24-h monitoring. Therefore, the relative abundance of plankton species apparently fluctuated among the samples, but no significant difference was noted according to G-test (p>0.05). Significant differences were observed between the samples obtained from a different locality (Kusuura in Yatsushiro Sea) and at different dates, suggesting that the influence of diurnal sampling bias on plankton diversity, determined using the MPS-based survey, was not significant and acceptable. PMID:26475937
NASA Astrophysics Data System (ADS)
De Carlo, E. H.; Mousseau, L.; Passafiume, O.; Drupp, P. S.; Gattuso, J.
2011-12-01
The purpose of the Service d'Observation de la Rade de Villefranche-sur-Mer (SO-RADE) is to study the temporal variability of hydrological conditions as well as the abundance and composition of holo- and meroplankton at a fixed station in the bay of Villefranche-sur-Mer, North West Mediterranean. The weekly data collected at this site, designated as "Point B (43° 41.10'N - 7° 18.94'E), since 1957 are recognized as a long-term time series describing the evolution of the hydrological conditions in a coastal environment. Since 2007, historical measurements of hydrological and biological conditions have been complemented by measurements of the CO2-carbonate system parameters. In this contribution we present CO2-carbonate system parameters and ancillary data for the period 2007-2010. The data are evaluated in the context of the physical and biogeochemical processes that contribute to the fluxes of CO2 between the ocean and atmosphere. Seasonal cycles of seawater pCO2 are controlled principally by variations in temperature, showing maxima in the summer and minima during the winters. Normalization of pCO2 to the mean seawater temperature (18oC) results in an apparent reversal of the seasonal cycle with maxima observed in the winters and minima in the summers, consistent with a control of pCO2 by primary productivity. Calculations of "instantaneous fluxes" of CO2 between the ocean and atmosphere show this area to be primarily a weak source of CO2 to the atmosphere during the summer and a weak sink during the winter and near neutral overall (range: -0.3 to +0.3 mmol CO2 m-2 h-1, average: 0.02 mmol CO2 m-2 h-1). We will also provide projections of errors incurred from the estimation of annualized fluxes of CO2 based on weekly measurements relative to daily and high-frequency (3 h) data such as those obtained at the Hawaii Kilo Nalu coastal time series station, which shows similar behavior to the Point B location despite significant differences in climate and hydrological conditions and the presence of a coral reef ecosystem.
NASA Astrophysics Data System (ADS)
Moreira, D. M.; Calmant, S.; Perosanz, F.; Santos, A.; Santos Da Silva, J.; Seyler, F.; Ramillien, G. L.; Monteiro, A.; Rotunno, O.; Shum, C.
2011-12-01
Applications of GNSS data is constantly being used in hydrology. One of the key applications is the characterization of river's longitudinal profiles, an information required to develop hydrological and hydrodynamic studies and to evaluate the quality of data obtained through space altimetry techniques. Some factors illustrate the challenge of establishing quality altimetry data from a GNSS receivers to obtain rivers profiles in Amazon Basin. GNSS reference network is sparse, the distance between survey points and reference stations is large, rivers have an extension of several thousands of kilometers. All these factors contribute in limiting the efficiency of classical techniques of GNSS data processing like double difference. In the present work we use the Gins-PC software developed at CNES / GRGS. We discuss the capability of the PPP kinematic with integer ambiguities fixing strategy implemented in GINS-PC in processing GPS data to calculate river's longitudinal profiles in the Amazon Basin. The profiles will be processed using data obtained from GPS receivers on boarding boats along the rivers of Amazon Basin such as Negro river, Madeira river and Amazon/Solimes river. For this purpose, field campaings were conducted between 2005 and 2010 by ANA ( Brazilian National Water Agency), CPRM (Brazilian Geologic Survey), IRD (French Institute of Research by Development), Hybam ( Hydrology of Amazon Basin), PROSUL (Research project by CNPQ/UFRJ) and FOAM (From Ocean to inland waters Altimetry Monitoring) river section project. Under the proposed framework, these profiles will be then compared with profiles obtained by water level variation data using altimetry data from tracks of the Jason-2 and ENVISAT missions. The profiles will be also used to levelling some gauge stations in Amazon Basin and gauge data will be used to obtain a temporal variation of these profiles. However some gauges are strongly affected by charge effects, mainly caused by the hydrological cycle of the Amazon basin. These effects can produce a variation of about 10 cm in amplitude of vertical coordinates also obtained by GPS. Therefore, we use GRACE data to convert the hydrologic load into crustal displacements to remove these effects.
D. S. Tobiason
2003-07-01
This Closure Report (CR) documents the activities undertaken to close Corrective Action Unit (CAU) 262: Area 25 Septic Systems and Underground Discharge Point, in accordance with the Federal Facility Agreement and Consent Order (FFACO) of 1996. Site closure was performed in accordance with the Nevada Division of Environmental Protection (NDEP)-approved Corrective Action Plan (CAP) for CAU 262 (U.S. Department of Energy, National Nuclear Security Administration Nevada Operations Office [NNSA/NV, 2002a]). CAU 262 is located at the Nevada Test Site (NTS) approximately 105 kilometers (65 miles) northwest of Las Vegas, Nevada. CAU 262 consists of the following nine Corrective Action Sites (CASs) located in Area 25 of the NTS: CAS 25-02-06, Underground Storage tank CAS 25-04-06, Septic Systems A and B CAS 25-04-07, Septic System CAS 25-05-03, Leachfield CAS 25-05-05, Leachfield CAS 25-05-06, Leachfield CAS 25-05-08, Radioactive Leachfield CAS 25-05-12, Leachfield CAS 25-51-01, Dry Well.
The Anti-Inflammatory Actions of Auricular Point Acupressure for Chronic Low Back Pain.
Lin, Wei-Chun; Yeh, Chao Hsing; Chien, Lung-Chang; Morone, Natalia E; Glick, Ronald M; Albers, Kathryn M
2015-01-01
Background. Auricular point acupressure (APA) is a promising treatment for pain management. Few studies have investigated the physiological mechanisms of APA analgesics. Method. In this pilot randomized clinical trial (RCT), a 4-week APA treatment was used to manage chronic low back pain (CLBP). Sixty-one participants were randomized into a real APA group (n = 32) or a sham APA group (n = 29). Blood samples, pain intensity, and physical function were collected at baseline and after 4 weeks of treatment. Results. Subjects in the real APA group reported a 56% reduction of pain intensity and a 26% improvement in physical function. Serum blood samples showed (1) a decrease in IL-1β, IL-2, IL-6, and calcitonin gene-related peptide [CGRP] and (2) an increase in IL-4. In contrast, subjects in the sham APA group (1) reported a 9% reduction in pain and a 2% improvement in physical function and (2) exhibited minimal changes of inflammatory cytokines and neuropeptides. Statistically significant differences in IL-4 and CGRP expression between the real and sham APA groups were verified. Conclusion. These findings suggest that APA treatment affects pain intensity through modulation of the immune system, as reflected by APA-induced changes in serum inflammatory cytokine and neuropeptide levels. PMID:26170869
The Anti-Inflammatory Actions of Auricular Point Acupressure for Chronic Low Back Pain
Lin, Wei-Chun; Yeh, Chao Hsing; Chien, Lung-Chang; Morone, Natalia E.; Glick, Ronald M.; Albers, Kathryn M.
2015-01-01
Background. Auricular point acupressure (APA) is a promising treatment for pain management. Few studies have investigated the physiological mechanisms of APA analgesics. Method. In this pilot randomized clinical trial (RCT), a 4-week APA treatment was used to manage chronic low back pain (CLBP). Sixty-one participants were randomized into a real APA group (n = 32) or a sham APA group (n = 29). Blood samples, pain intensity, and physical function were collected at baseline and after 4 weeks of treatment. Results. Subjects in the real APA group reported a 56% reduction of pain intensity and a 26% improvement in physical function. Serum blood samples showed (1) a decrease in IL-1β, IL-2, IL-6, and calcitonin gene-related peptide [CGRP] and (2) an increase in IL-4. In contrast, subjects in the sham APA group (1) reported a 9% reduction in pain and a 2% improvement in physical function and (2) exhibited minimal changes of inflammatory cytokines and neuropeptides. Statistically significant differences in IL-4 and CGRP expression between the real and sham APA groups were verified. Conclusion. These findings suggest that APA treatment affects pain intensity through modulation of the immune system, as reflected by APA-induced changes in serum inflammatory cytokine and neuropeptide levels. PMID:26170869
Fixed bed hydrocracking process
MacLean, A.J.; Holloway, R.L.; Lawson, V.A.; Cronen, J.W.
1990-02-20
This patent describes a process for converting a gas oil range petroleum feedstock into lighter petroleum products. It comprises: charging the gas oil range petroleum feedstock and hydrogen to a first fixed bed hydrocracking zone containing a hydrocracking catalyst at hydrocracking conditions to produce a first hydrocracking zone product stream; separating the first fixed bed hydrocracking zone product stream in a fractionation zone into a petroleum products stream and a bottoms stream; charging the bottoms stream and hydrogen to a second fixed bed hydrocracking zone containing a hydrocracking catalyst at hydrocracking conditions to produce a second fixed bed hydrocracking zone product stream; cooling the second fixed bed hydrocracking zone product stream to a temperature below about 250{degrees}F; recycling a first portion of the cooled second fixed bed hydrocracking zone product stream to the fractionation zone; removing materials having a boiling range from about 500{degrees} to about 650{degrees}F and a heavy bottoms stream having a boiling point above about 1050{degrees}F from a second portion of the cooled second fixed bed hydrocracking zone product stream to product a treated second portion; and recycling the treated second portion to the first fixed bed hydrocracking zone.
Sexton, Alec N; Regalado, Samuel G; Lai, Christine S; Cost, Gregory J; O'Neil, Colleen M; Urnov, Fyodor D; Gregory, Philip D; Jaenisch, Rudolf; Collins, Kathleen; Hockemeyer, Dirk
2014-09-01
Telomere length homeostasis is essential for the long-term survival of stem cells, and its set point determines the proliferative capacity of differentiated cell lineages by restricting the reservoir of telomeric repeats. Knockdown and overexpression studies in human tumor cells showed that the shelterin subunit TPP1 recruits telomerase to telomeres through a region termed the TEL patch. However, these studies do not resolve whether the TPP1 TEL patch is the only mechanism for telomerase recruitment and whether telomerase regulation studied in tumor cells is representative of nontransformed cells such as stem cells. Using genome engineering of human embryonic stem cells, which have physiological telomere length homeostasis, we establish that the TPP1 TEL patch is genetically essential for telomere elongation and thus long-term cell viability. Furthermore, genetic bypass, protein fusion, and intragenic complementation assays define two distinct additional mechanisms of TPP1 involvement in telomerase action at telomeres. We demonstrate that TPP1 provides an essential step of telomerase activation as well as feedback regulation of telomerase by telomere length, which is necessary to determine the appropriate telomere length set point in human embryonic stem cells. These studies reveal and resolve multiple TPP1 roles in telomere elongation and stem cell telomere length homeostasis. PMID:25128433
Gauge fixing and equivariant cohomology
NASA Astrophysics Data System (ADS)
Rogers, Alice
2005-10-01
The supersymmetric model developed by Witten (1982 J. Differ. Geom. 17 661 92) to study the equivariant cohomology of a manifold with an isometric circle action is derived from the BRST quantization of a simple classical model. The gauge-fixing process is carefully analysed, and demonstrates that different choices of gauge-fixing fermion can lead to different quantum theories.
DOE/NV
1999-05-20
This Corrective Action Investigation Plan (CAIP) has been developed in accordance with the Federal Facility Agreement and Consent Order (FFACO) that was agreed to by the US Department of Energy, Nevada Operations Office (DOE/NV); the State of Nevada Division of Environmental Protection (NDEP); and the US Department of Defense (FFACO, 1996). The CAIP is a document that provides or references all of the specific information for investigation activities associated with Corrective Action Units (CAUs) or Corrective Action Sites (CASs). According to the FFACO (1996), CASs are sites potentially requiring corrective action(s) and may include solid waste management units or individual disposal or release sites. Corrective Action Units consist of one or more CASs grouped together based on geography, technical similarity, or agency responsibility for the purpose of determining corrective actions. This CAIP contains the environmental sample collection objectives and the criteria for conducting site investigation activities at the Underground Discharge Points (UDPs) included in both CAU 406 and CAU 429. The CAUs are located in Area 3 and Area 9 of the Tonopah Test Range (TTR). The TTR, included in the Nellis Air Force Range, is approximately 255 kilometers (km) (140 miles [mi]) northwest of Las Vegas, Nevada.
NASA Astrophysics Data System (ADS)
Sonoda, H.
2015-10-01
We introduce the concept of equivalence among Wilson actions. Applying the concept to a real scalar theory on a Euclidean space, we derive the exact renormalization group transformation of K. G. Wilson, and give a simple proof of universality of the critical exponents at any fixed point of the exact renormalization group transformation. We also show how to reduce the original formalism of Wilson to the simplified formalism by J. Polchinski.
ERIC Educational Resources Information Center
Bonnet, Lauren Kravetz
2012-01-01
This single-subject research study was designed to examine the effects of point-of-view video modeling (POVM) on the symbolic play actions and play-associated language of four preschool students with autism. A multiple baseline design across participants was conducted in order to evaluate the effectiveness of using POVM as an intervention for…
ERIC Educational Resources Information Center
Zambrana, Imac M.; Ystrom, Eivind; Schjolberg, Synnve; Pons, Francisco
2013-01-01
This study examined whether poor pointing gestures and imitative actions at 18 months of age uniquely predicted late language production at 36 months, beyond the role of poor language at 18 months of age. Data from the Norwegian Mother and Child Cohort Study were utilized. Maternal reports of the children's nonverbal skills and language were…
NASA Astrophysics Data System (ADS)
Lavin, Alicia; Cano, Daniel; González-Pola, Cesar; Tel, Elena; Rodriguez, Carmen; Ruiz, Manuel; Somavilla, Raquel
2015-04-01
Long term time series are an important tool for increasing the knowledge of ocean processes as well as for studying water masses variability in different time scales and changes and tendencies in marine ecosystems. Time series has been classically obtained by oceanographic ships that regularly cover standard sections and stations. From 1991, shelf and slope waters of the Southern Bay of Biscay are regularly sampled in a monthly hydrographic line north of Santander to a depth of 1000 m in early stages and for the whole water column down to 2580 m in recent times. Nearby, in June 2007, the IEO deployed an oceanic-meteorological buoy (AGL Buoy, 43° 50.67'N; 3° 46.20'W, and 40 km offshore, www.boya-agl.st.ieo.es). The long-term hydrographical record have allowed to define the seasonality, trends, and interannual variability at all levels, including the mixing layer and the main water masses North Atlantic Central Water and Mediterranean Water. The relation of these changes with high frequency surface conditions has been examined using the AGL buoy data from 2007 as well as satellite and reanalysis data. On that context and using that combination of sources, some products and quality controlled series of high interest and utility for scientific purposes have been developed and are offered hourly in the web page. Main products obtained are: SST and SSS anomalies, wave significant height character with respect to monthly average, and currents with respect to seasonal averages. Ocean-atmosphere heat fluxes (latent and sensible) are computed from the buoy atmospheric and oceanic measurements. Estimations of the mixed layer depth and bulk series at different water levels are provided in a monthly basis. Quality controlled series are provided for sea surface salinity, oxygen and chlorophyll data. Some sensors are particularly affected by biofouling, and monthly visits to the buoy permit to follow these sensors behaviour. Chlorophyll-fluorescence sensor is the main concern, but Dissolved Oxygen sensor is also problematic. Periods of realistic smooth variations present strong offset that is corrected based on the Winkler analysis of water samples. The incorporation of these observatories on larger scale research programs, as done in 2003 in the framework of the VACLAN and COVACLAN projects, is important in order to provide them with a larger spatial dimension and maximize its utility for process-oriented studies. In 2003, the Santander section was extended 90 miles offshore in the framework of a large-scale hydrographic and circulation monitoring program. Partnerships in a large EU project as FixO3 has provided tools for coordination, homogenization and data validation as well as improve the use of chemical-biological data.
Lynn Kidman
2008-10-01
This document constitutes an addendum to the March 2000, Corrective Action Decision Document / Closure Report for Corrective Action Unit 406: Area 3 Building 03-74 & 03-58 Underground Discharge Points and Corrective Action Unit 429: Area 3 Building 03-55 & Area 9 Building 09-52 Underground Discharge Points (TTR) as described in the document Recommendations and Justifications for Modifications for Use Restrictions Established under the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office Federal Facility Agreement and Consent Order (UR Modification document) dated February 2008. The UR Modification document was approved by NDEP on February 26, 2008. The approval of the UR Modification document constituted approval of each of the recommended UR modifications. In conformance with the UR Modification document, this addendum consists of: • This cover page that refers the reader to the UR Modification document for additional information • The cover and signature pages of the UR Modification document • The NDEP approval letter • The corresponding section of the UR Modification document This addendum provides the documentation justifying the cancellation of the UR for CAS 03-51-001-0355 – Photo Shop UDP, Drains in CAU 429. It should be noted that there are no changes to CAU 406. This UR was established as part of a Federal Facility Agreement and Consent Order (FFACO) corrective action and is based on the presence of contaminants at concentrations greater than the action levels established at the time of the initial investigation (FFACO, 1996; as amended August 2006). Since this UR was established, practices and procedures relating to the implementation of risk-based corrective actions (RBCA) have changed. Therefore, this UR was re-evaluated against the current RBCA criteria as defined in the Industrial Sites Project Establishment of Final Action Levels (NNSA/NSO, 2006c). This re-evaluation consisted of comparing the original data (used to define the need for the UR) to risk-based final action levels (FALs) developed using the current Industrial Sites RBCA process. The re-evaluation resulted in a recommendation to remove the UR because contamination is not present at the site above the risk-based FALs. Requirements for inspecting and maintaining this UR will be canceled, and the postings and signage at this site will be removed. Fencing and posting may be present at this site that are unrelated to the FFACO UR such as for radiological control purposes as required by the NV/YMP Radiological Control Manual (NNSA/NSO, 2004f). This modification will not affect or modify any non-FFACO requirements for fencing, posting, or monitoring at this site.
NNSA /NV
2000-07-20
This corrective action investigation plan contains the U.S. Department of Energy, Nevada Operations Office's approach to collect data necessary to evaluate corrective action alternatives appropriate for the closure of Corrective Action Unit (CAU) 262 under the Federal Facility Agreement and Consent Order. Corrective Action Unit 262 consists of nine Corrective Action Sites (CASs): Underground Storage Tank (25-02-06), Septic Systems A and B (25-04-06), Septic System (25-04-07), Leachfield (25-05-03), Leachfield (25-05-05), Leachfield (25-05-06), Radioactive Leachfield (25-05-08), Leachfield (25-05-12), and Dry Well (25-51-01). Situated in Area 25 at the Nevada Test Site (NTS), sites addressed by CAU 262 are located at the Reactor-Maintenance, Assembly, and Disassembly (R-MAD); Test Cell C; and Engine-Maintenance, Assembly, and Disassembly (E-MAD) facilities. The R-MAD, Test Cell C, and E-MAD facilities supported nuclear rocket reactor and engine testing as part of the Nuclear Rocket Development Station. The activities associated with the testing program were conducted between 1958 and 1973. Based on site history collected to support the Data Quality Objectives process, contaminants of potential concern (COPCs) for the site include oil/diesel-range total petroleum hydrocarbons, volatile organic compounds, semivolatile organic compounds, polychlorinated biphenyls, Resource Conservation and Recovery Act metals, and gamma-emitting radionuclides, isotopic uranium, isotopic plutonium, strontium-90, and tritium. The scope of the corrective action field investigation at the CAU will include the inspection of portions of the collection systems, sampling the contents of collection system features in situ of leachfield logging materials, surface soil sampling, collection of samples of soil underlying the base of inlet and outfall ends of septic tanks and outfall ends of diversion structures and distribution boxes, collection of soil samples from biased or a combination of biased and random locations within the boundaries of the leachfields, collection of soil samples at stepout locations (where needed) to further define lateral and vertical extent of contamination, conduction of discrete field screening, and logging of soil borings and collection of geotechnical samples to assess soil characteristics. Historical information indicates that significant quantities of radioactive material were produced during the rocket engine testing program, some of which was disposed of in radioactive waste disposal systems (posted leachfields) at each of these locations. Process and sanitary effluents were generated and disposed of in other leachfields. The results of this field investigation will be used to develop and evaluate corrective action alternatives for these CASs.
Zambrana, Imac M.; Ystrom, Eivind; Schjølberg, Synnve; Pons, Francisco
2012-01-01
This study examined whether poor pointing gestures and imitative actions at 18 months of age uniquely predicted late language production at 36 months, beyond the role of poor language at 18 months of age. Data from the Norwegian Mother and Child Cohort Study were utilized. Maternal reports of the children’s nonverbal skills and language were gathered for 42,517 children aged 18 months and for 28,107 of the same children at 36 months. Panel analysis of latent variables revealed that imitative actions, language comprehension, and language production uniquely contributed to predicting late development of language production, while pointing gestures did not. It is suggested that the results can be explained by underlying symbolic representational skills at 18 months. PMID:23033814
On the existence of Feigenbaum's fixed point
NASA Astrophysics Data System (ADS)
Campanino, M.; Epstein, H.
1981-03-01
We give a proof of the existence of a C 2, even solution of Feigenbaum's functional equation 220_2005_Article_BF01942063_TeX2GIFE1.gif g{text{(}}x) = - λ _0^{ - 1} g{text{(}}g( - λ _0 x)),g{text{(0) = 1,}} where g is a map of [-1, 1] into itself. It extends to a real analytic function over ℝ.
Alarm points for fixed oxygen monitors
Miller, G.C.
1987-05-01
Oxygen concentration monitors were installed in a vault where numerous pipes carried inert cryogens and gases to the Mirror Fusion Test Facility (MFTF-B) experimental vessel at Lawrence Livermore National Laboratory (LLNL). The problems associated with oxygen-monitoring systems and the reasons why such monitors were installed were reviewed. As a result of this review, the MFTF-B monitors were set to sound an evacuation alarm when the oxygen concentration fell below 18%. We chose the 18% alarm criterion to minimize false alarms and to allow time for personnel to escape in an oxygen-deficient environment.
NASA Astrophysics Data System (ADS)
Nedialkov, Sasho; Bosma, Rien; Dierikx, Erik
2013-01-01
A bilateral comparison has been organized between VSL, The Netherlands, and BIM, Bulgaria, of the realisations of the international temperature scale ITS-90 at the fixed points of Hg, H2O, Ga, In, Sn and Zn using a long-stem SPRT of very good stability as the transfer device. This comparison is registered as EURAMET project T-K3.1 in the BIPM key comparison database and its results are linked to those of key comparison CCT-K3. This comparison was organized in the framework of Phare project BG 2005/017-353.02.02, Lot 1, and is in this framework financed by the EU. This project ran from March 2008 to the end of February 2009. For all points of the measurements, a good agreement between the results obtained by BIM and in CCT-K3 could be demonstrated. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCT, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Lynn Kidman
2008-10-01
This document constitutes an addendum to the July 1999, Closure Report for Corrective Action Unit 423: Area 3 Building 0360 Underground Discharge Point, Tonopah Test Range, Nevada as described in the document Recommendations and Justifications for Modifications for Use Restrictions Established under the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office Federal Facility Agreement and Consent Order (UR Modification document) dated February 2008. The UR Modification document was approved by NDEP on February 26, 2008. The approval of the UR Modification document constituted approval of each of the recommended UR modifications. In conformance with the UR Modification document, this addendum consists of: • This cover page that refers the reader to the UR Modification document for additional information • The cover and signature pages of the UR Modification document • The NDEP approval letter • The corresponding section of the UR Modification document This addendum provides the documentation justifying the cancellation of the UR for CAS 03-02-002-0308, Underground Discharge Point. This UR was established as part of a Federal Facility Agreement and Consent Order (FFACO) corrective action and is based on the presence of contaminants at concentrations greater than the action levels established at the time of the initial investigation (FFACO, 1996; as amended August 2006). Since this UR was established, practices and procedures relating to the implementation of risk-based corrective actions (RBCA) have changed. Therefore, this UR was re-evaluated against the current RBCA criteria as defined in the Industrial Sites Project Establishment of Final Action Levels (NNSA/NSO, 2006c). This re-evaluation consisted of comparing the original data (used to define the need for the UR) to risk-based final action levels (FALs) developed using the current Industrial Sites RBCA process. The re-evaluation resulted in a recommendation to remove the UR because contamination is not present at the site above the risk-based FALs. Requirements for inspecting and maintaining this UR will be canceled, and the postings and signage at this site will be removed. Fencing and posting may be present at this site that are unrelated to the FFACO UR such as for radiological control purposes as required by the NV/YMP Radiological Control Manual (NNSA/NSO, 2004f). This modification will not affect or modify any non-FFACO requirements for fencing, posting, or monitoring at this site.
Lynn Kidman
2008-10-01
This document constitutes an addendum to the July 2003, Closure Report for Corrective Action Unit 262: Area 25 Septic Systems and Underground Discharge Point as described in the document Recommendations and Justifications for Modifications for Use Restrictions Established under the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office Federal Facility Agreement and Consent Order (UR Modification document) dated February 2008. The UR Modification document was approved by NDEP on February 26, 2008. The approval of the UR Modification document constituted approval of each of the recommended UR modifications.
NASA Astrophysics Data System (ADS)
Siegel, J.; Siegel, Edward Carl-Ludwig
2011-03-01
Cook-Levin computational-"complexity"(C-C) algorithmic-equivalence reduction-theorem reducibility equivalence to renormalization-(semi)-group phase-transitions critical-phenomena statistical-physics universality-classes fixed-points, is exploited with Gauss modular/clock-arithmetic/model congruences = signal X noise PRODUCT reinterpretation. Siegel-Baez FUZZYICS=CATEGORYICS(SON of ``TRIZ''): Category-Semantics(C-S) tabular list-format truth-table matrix analytics predicts and implements "noise"-induced phase-transitions (NITs) to accelerate versus to decelerate Harel [Algorithmics(1987)]-Sipser[Intro. Theory Computation(1997) algorithmic C-C: "NIT-picking" to optimize optimization-problems optimally(OOPO). Versus iso-"noise" power-spectrum quantitative-only amplitude/magnitude-only variation stochastic-resonance, this "NIT-picking" is "noise" power-spectrum QUALitative-type variation via quantitative critical-exponents variation. Computer-"science" algorithmic C-C models: Turing-machine, finite-state-models/automata, are identified as early-days once-workable but NOW ONLY LIMITING CRUTCHES IMPEDING latter-days new-insights!!!
Nagai, Yoshio
2015-03-01
Many patients with type 2 diabetes mellitus(T2DM) do not achieve satisfactory glycemic control by monotherapy alone, and often require multiple oral hypoglycemic agents (OHAs). Combining OHAs with complementary mechanisms of action is fundamental to the management of T2DM. Fixed-dose combination therapy(FDC) offers a method of simplifying complex regimens. Efficacy and tolerability appear to be similar between FDC and treatment with individual agents. In addition, FDC can enhance adherence and improved adherence may result in improved glycemic control. Four FDC agents are available in Japan: pioglitazone-glimepiride, pioglitazone-metformin, pioglitazone-alogliptin, and voglibose-mitiglinide. In this review, the advantages and disadvantages of these four combinations are identified and discussed. PMID:25812374
78 FR 20705 - Fixed Income Roundtable
Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-05
... COMMISSION Fixed Income Roundtable AGENCY: Securities and Exchange Commission. ACTION: Notice of roundtable..., efficiency, and other aspects of fixed income markets. The roundtable will focus on the municipal securities, corporate bonds, and asset-backed securities markets. The roundtable discussion will be held in the...
Swinney, Zachary T.; Haubrich, Brad A.; Xia, Shuangluo; Ramesha, Chakk; Gomez, Stephen R.; Guyett, Paul; Mensa-Wilmot, Kojo; Swinney, David C.
2016-01-01
Background New therapeutics are needed for neglected tropical diseases including Human African trypanosomiasis (HAT), a progressive and fatal disease caused by the protozoan parasites Trypanosoma brucei gambiense and T. b. rhodesiense. There is a need for simple, efficient, cost effective methods to identify new molecules with unique molecular mechanisms of action (MMOAs). The mechanistic features of a binding mode, such as competition with endogenous substrates and time-dependence can affect the observed inhibitory IC50, and differentiate molecules and their therapeutic usefulness. Simple screening methods to determine time-dependence and competition can be used to differentiate compounds with different MMOAs in order to identify new therapeutic opportunities. Methodology/Principal Findings In this work we report a four point screening methodology to evaluate the time-dependence and competition for inhibition of GSK3β protein kinase isolated from T. brucei. Using this method, we identified tideglusib as a time-dependent inhibitor whose mechanism of action is time-dependent, ATP competitive upon initial binding, which transitions to ATP non-competitive with time. The enzyme activity was not recovered following 100-fold dilution of the buffer consistent with an irreversible mechanism of action. This is in contrast to the T. brucei GSK3β inhibitor GW8510, whose inhibition was competitive with ATP, not time-dependent at all measured time points and reversible in dilution experiments. The activity of tideglusib against T. brucei parasites was confirmed by inhibition of parasite proliferation (GI50 of 2.3 μM). Conclusions/Significance Altogether this work demonstrates a straightforward method for determining molecular mechanisms of action and its application for mechanistic differentiation of two potent TbGSK3β inhibitors. The four point MMOA method identified tideglusib as a mechanistically differentiated TbGSK3β inhibitor. Tideglusib was shown to inhibit parasite growth in this work, and has been reported to be well tolerated in one year of dosing in human clinical studies. Consequently, further supportive studies on the potential therapeutic usefulness of tideglusib for HAT are justified. PMID:26942720
NASA Astrophysics Data System (ADS)
Cherepetskaya, E. B.; Karabutov, A. A.; Kaptilniy, A. G.; Ksenofontov, D. M.; Makarov, V. A.; Podymova, N. B.
2015-12-01
This paper is a report on the novel experimental method of the study of the thermodynamic parameters of thin aluminum films in the critical point region. The controlled supercritical state of aluminum is achieved for the first time as a result of the heating of these films by the absorption of the powerful nanosecond pulse of Q-switched Nd:YAG laser at the fundamental wavelength. The possibility is demonstrated to find simultaneously the temporal dependencies of the temperature, of the pressure and of the density of aluminum during the experiment with the thin aluminum films confined at both sides by the quartz glass substrates. These dependencies are obtained taking into account the nonlinear dependence on the incident laser intensity of the light reflection coefficient from the irradiated surface of aluminum. For the first time the thermodynamic cooling cycle of aluminum after its heating by the powerful nanosecond laser pulse is plotted in the space of variables’ temperature—pressure and temperature—density that get into the supercritical region.
Matter induced bimetric actions for gravity
Manrique, Elisa; Reuter, Martin; Saueressig, Frank
2011-02-15
Research Highlights: > Gravitational effective action in the bimetric truncation. > RG flow in the large N limit of matter coupled to gravity. > Asymptotically safe theory found in the large N expansion. - Abstract: The gravitational effective average action is studied in a bimetric truncation with a nontrivial background field dependence, and its renormalization group flow due to a scalar multiplet coupled to gravity is derived. Neglecting the metric contributions to the corresponding beta functions, the analysis of its fixed points reveals that, even on the new enlarged theory space which includes bimetric action functionals, the theory is asymptotically safe in the large N expansion.
76 FR 65118 - Drawbridge Operation Regulation; Bear Creek, Sparrows Point, MD
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-20
... Point, MD AGENCY: Coast Guard, DHS. ACTION: Final rule. SUMMARY: The Coast Guard is canceling a portion... Avenue) highway toll drawbridge across Bear Creek, mile 1.5, Sparrows Point, MD was replaced with a fixed... cause finds that those procedures are ``impracticable, unnecessary, or contrary ] to the public...
Shirzad, A.
2007-08-15
Gauge fixing may be done in different ways. We show that using the chain structure to describe a constrained system enables us to use either a full gauge, in which all gauged degrees of freedom are determined, or a partial gauge, in which some first class constraints remain as subsidiary conditions to be imposed on the solutions of the equations of motion. We also show that the number of constants of motion depends on the level in a constraint chain in which the gauge fixing condition is imposed. The relativistic point particle, electromagnetism, and the Polyakov string are discussed as examples and full or partial gauges are distinguished.
Hsieh, Chiu-Lan; Wang, Hui-Er; Tsai, Wan-Jane; Peng, Chiung-Chi; Peng, Robert Y
2012-01-27
The teratogenicity of antiepilepsy drug valproic acid (VPA) mostly is found in genetic and somatic levels, causing teratogenesis involving neurotubular defects (NTDs), anencephaly, lumbosacral meningomyelocele, and leg dysfunction due to spina bifida aperta. A diversity of nutraceutics have been tried to alleviate the risk of VPA-teratogenicity. The effect was varying. In order to promote the preventive prescription, to find out its action mechanism can be rather crucial. We used chicken embryo model to try the effect of folic acid (FA), ascorbic acid (AA), and N-acetyl cysteine (NAC). VPA at 30mM showed the higher malformation rate (66.7%) with the least mortality (22.2%). Pathological findings indicated that the cervical muscle was more susceptible to VPA injury than the ankle muscle. VPA downregulated levels of superoxide dismutase (SOD), glutathione (GSH), histone deacetylase (HDAC) and folate, and upregulated H(2)O(2) and homocysteine. FA, AA, and NAC significantly upregulated SOD, but only AA alone activated GSH. AA and NAC downregulated H(2)O(2), while FA was totally ineffective. All three nutraceutics comparably rescued HDAC with simultaneously suppressed homocysteine accumulation and folate re-elevation, although less effectively by NAC. Based on these data, we conclude VPA possesses "Multiple Point Action Mechanism". In addition to affecting the cited transcription and translation levels, we hypothesize that VPA competitively antagonize the glutamic acid to couple with pteroic acid in biosynthesis of dihydrofolic acid (DHFA). H(2)O(2) directly destroyed the NADPH reducing system at dihydrofolate reductase (DHFR) and methylene tetrahydrofolate reductase (MTHFR) levels, while completely restored by AA, an implication in preservation of intact apoenzymes. In addition, the GSH-GSSG system is sandwiched between the reducing systems NADPH/NADP and DHA-AA, its net balance is highly dependent on in situ in vivo Redox state, hence folic acid transformation is varying. To rescue the VPA-induced teratogenicity, simultaneous multiple prescriptions are suggested. PMID:22051200
Labib, Sarah; Bourdon-Lacombe, Julie; Kuo, Byron; Buick, Julie K.; Lemieux, France; Williams, Andrew; Halappanavar, Sabina; Malik, Amal; Luijten, Mirjam; Aubrecht, Jiri; Hyduke, Daniel R.; Fornace, Albert J.; Swartz, Carol D.; Recio, Leslie; Yauk, Carole L.
2015-01-01
Toxicogenomics is proposed to be a useful tool in human health risk assessment. However, a systematic comparison of traditional risk assessment approaches with those applying toxicogenomics has never been done. We conducted a case study to evaluate the utility of toxicogenomics in the risk assessment of benzo[a]pyrene (BaP), a well-studied carcinogen, for drinking water exposures. Our study was intended to compare methodologies, not to evaluate drinking water safety. We compared traditional (RA1), genomics-informed (RA2) and genomics-only (RA3) approaches. RA2 and RA3 applied toxicogenomics data from human cell cultures and mice exposed to BaP to determine if these data could provide insight into BaP's mode of action (MOA) and derive tissue-specific points of departure (POD). Our global gene expression analysis supported that BaP is genotoxic in mice and allowed the development of a detailed MOA. Toxicogenomics analysis in human lymphoblastoid TK6 cells demonstrated a high degree of consistency in perturbed pathways with animal tissues. Quantitatively, the PODs for traditional and transcriptional approaches were similar (liver 1.2 vs. 1.0 mg/kg-bw/day; lung 0.8 vs. 3.7 mg/kg-bw/day; forestomach 0.5 vs. 7.4 mg/kg-bw/day). RA3, which applied toxicogenomics in the absence of apical toxicology data, demonstrates that this approach provides useful information in data-poor situations. Overall, our study supports the use of toxicogenomics as a relatively fast and cost-effective tool for hazard identification, preliminary evaluation of potential carcinogens, and carcinogenic potency, in addition to identifying current limitations and practical questions for future work. PMID:25605026
A proper fixed functional for four-dimensional Quantum Einstein Gravity
NASA Astrophysics Data System (ADS)
Demmel, Maximilian; Saueressig, Frank; Zanusso, Omar
2015-08-01
Realizing a quantum theory for gravity based on Asymptotic Safety hinges on the existence of a non-Gaussian fixed point of the theory's renormalization group flow. In this work, we use the functional renormalization group equation for the effective average action to study the fixed point underlying Quantum Einstein Gravity at the functional level including an infinite number of scale-dependent coupling constants. We formulate a list of guiding principles underlying the construction of a partial differential equation encoding the scale-dependence of f( R)-gravity. We show that this equation admits a unique, globally well-defined fixed functional describing the non-Gaussian fixed point at the level of functions of the scalar curvature. This solution is constructed explicitly via a numerical double-shooting method. In the UV, this solution is in good agreement with results from polynomial expansions including a finite number of coupling constants, while it scales proportional to R 2, dressed up with non-analytic terms, in the IR. We demonstrate that its structure is mainly governed by the conformal sector of the flow equation. The relation of our work to previous, partial constructions of similar scaling solutions is discussed.
Future Fixed Target Facilities
Melnitchouk, Wolodymyr
2009-01-01
We review plans for future fixed target lepton- and hadron-scattering facilities, including the 12 GeV upgraded CEBAF accelerator at Jefferson Lab, neutrino beam facilities at Fermilab, and the antiproton PANDA facility at FAIR. We also briefly review recent theoretical developments which will aid in the interpretation of the data expected from these facilities.
NASA Technical Reports Server (NTRS)
Lynnes, Chris
2014-01-01
Three current search engines are queried for ozone data at the GES DISC. The results range from sub-optimal to counter-intuitive. We propose a method to fix dataset search by implementing a robust relevancy ranking scheme. The relevancy ranking scheme is based on several heuristics culled from more than 20 years of helping users select datasets.
Neal, Daniel R.
2000-01-01
A rigid mount and method of mounting for a wavefront sensor. A wavefront dissector, such as a lenslet array, is rigidly mounted at a fixed distance relative to an imager, such as a CCD camera, without need for a relay imaging lens therebetween.
NASA Astrophysics Data System (ADS)
Reaney, S. M.
2014-12-01
Catchment systems deliver many benefits to society and ecology but also produce a range of undesirable externalities including flooding, diffuse pollution from agriculture, forestry and urban areas and the export of FIOs. These diffuse pressures are coupled with increasing stream temperature pressures on river from projected climate change. These pressures can be reduced through actions at the landscape scale but are often tackled individually. Any intervention may have benefits for other pressures and hence the challenge is to consider all of the different pressures simultaneously to find solutions with high levels of cross-pressure benefits. The general approach taken within this research has been to use simple but spatially distributed models to predict the pattern of each of the pressures at the landscape scale. These models follow a minimum information requirement approach along the lines of the SCIMAP modelling approach (www.scimap.org.uk). This approach aims to capture the key features of the processes in relative rather than an absolute sense and hence is good at determining key locations to act within a landscape for maximum benefit. The core of the approach is to define the critical sources areas for each pressure based on the analysis of the pattern of the pressure in the landscape and the connectivity from the sources areas to the rivers and lakes. To identify the optimal locations with the landscape for mitigation actions, the benefit of a mitigation action at each location in the landscape needs to be considered. However, as one action has been made, it may change the suitability of other locations in the landscape. For example, as tree cover reduces the temperature in one river reach, the impacts of this cooling are transported downstream with the flow. Therefore, actions need to be considered in sets across multiple sites and objectives to identify the optimal actions set. These modelling results are integrated into a decision support tool which allows the user to explore the implications of considering an individual pressure as opposed to the set of pressures. This is achieved by allowing the user to change the importance of different pressures to identify the optimal locations for a custom combination of pressures. For example, reductions in flood risk can be prioritized over reductions in fine sediment.
29 CFR 1910.27 - Fixed ladders.
Code of Federal Regulations, 2014 CFR
2014-07-01
... Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR OCCUPATIONAL SAFETY AND HEALTH STANDARDS Walking-Working Surfaces § 1910.27 Fixed ladders. (a) Design... points as will cause the maximum stress in the structural member being considered. (iv) The weight of...
Willacy, Erika; Bratton, Shelly
2016-01-01
Public health management is a pillar of public health practice. Only through effective management can research, theory, and scientific innovation be translated into successful public health action. With this in mind, the U.S. Centers for Disease Control and Prevention (CDC) has developed an innovative program called Improving Public Health Management for Action (IMPACT) which aims to address this critical need by building an effective cadre of public health managers to work alongside scientists to prepare for and respond to disease threats and to effectively implement public health programs. IMPACT is a 2-year, experiential learning program that provides fellows with the management tools and opportunities to apply their new knowledge in the field, all while continuing to serve the Ministry of Health (MoH). IMPACT will launch in 2016 in 2 countries with the intent of expanding to additional countries in future years resulting in a well-trained cadre of public health managers around the world. PMID:26673653
NASA Technical Reports Server (NTRS)
Fenn, D. B.; Viterna, L. A.
1978-01-01
Wind turbines designed for fixed pitch operation offer potential reductions in the cost of the machine by eliminating many costly components. It was shown that a rotor can be designed which produces the same energy annually as Mod-0 but which regulates its power automatically by progressively stalling the blades as wind speed increases. Effects of blade twist, taper, root cutout, and airfoil shape on performance are discussed as well as various starting technqiues.
Tipton, H.R.
1984-07-31
A fixed solar energy collector system has facing panels of different size forming a Vee-shaped trough open at its base and supporting a plurality of highly reflective convex reflectors strategically disposed upon said panels in reflective relationship to a plurality of Fresnel lenses positioned at the base of the trough. A suitable reflector, disposed beneath the Fresnel lenses, directs the reflected energy to a heat-needy target.
Riedel, H-P; Ellger-Rüttgardt, S; Karbe, H; Niehaus, M; Rauch, A; Schian, H-M; Schmidt, C; Schott, T; Schröder, H; Spijkers, W; Wittwer, U
2009-12-01
Established by the Federal Ministry of Labour and Social Affairs (BMAS) in October 2007, the Scientific Expert Group RehaFutur had been commissioned to elaborate cornerstones for the medium- and long-term development of vocational rehabilitation of adults with disabilities (re-integration). Initial questions inter alia were as follows: Which function should vocational rehabilitation have in a service- and knowledge-oriented working world that will increasingly be affected by demographic change? How can disabled persons' right to occupational participation by way of vocational rehabilitation, a right stipulated both under the German constitution and in German law, be realized as needed also in the future? Various fields of action have been derived on the basis, for one, of an investigation of the factors, social law, social and education policy as well as European, influencing vocational rehabilitation and, for the other, of an evaluation of current labour market and demographic developments. Dealt with in the fields of action outlined are the aspects: equitable opportunities of access, developmental and needs orientation, closeness to the real occupational and working world, as well as the role of self-determination and self-responsibility. The fields of action are to be understood as framework concept for shaping a cross-actor innovation process. Sustainable vocational rehabilitation is characterized in particular by the fact that it is specifically targeted at promoting disabled persons' self-determination and self-responsibility actively using these in the process and that it strengthens an independent lifestyle, ensures social participation by inclusive structures; also, it facilitates continued participation in working life by ongoing education involving holistic development of professional and personal competencies oriented towards the individual's resources and potentials, safeguarding it by systematic networking with companies. The concept presented for vocational rehabilitation of adults with disabilities encompasses a change of paradigms which service carriers and providers will have to face jointly and including the service users, the rehabilitants. PMID:20069522
Fixed target facility at the SSC
Loken, S.C.; Morfin, J.G.
1985-01-01
The question of whether a facility for fixed target physics should be provided at the SSC must be answered before the final technical design of the SSC can be completed, particularly if the eventual form of extraction would influence the magnet design. To this end, an enthusiastic group of experimentalists, theoreticians and accelerator specialists have studied this point. The accelerator physics issues were addressed by a group led by E. Colton whose report is contained in these proceedings. The physics addressable by fixed target was considered by many of the Physics area working groups and in particular by the Structure Function Group. This report is the summary of the working group which considered various SSC fixed target experiments and determined which types of beams and detectors would be required. 13 references, 5 figures.
Fixed Sagittal Plane Imbalance
Savage, Jason W.; Patel, Alpesh A.
2014-01-01
Study Design Literature review. Objective To discuss the evaluation and management of fixed sagittal plane imbalance. Methods A comprehensive literature review was performed on the preoperative evaluation of patients with sagittal plane malalignment, as well as the surgical strategies to address sagittal plane deformity. Results Sagittal plane imbalance is often caused by de novo scoliosis or iatrogenic flat back deformity. Understanding the etiology and magnitude of sagittal malalignment is crucial in realignment planning. Objective parameters have been developed to guide surgeons in determining how much correction is needed to achieve favorable outcomes. Currently, the goals of surgery are to restore a sagittal vertical axis < 5 cm, pelvic tilt < 20 degrees, and lumbar lordosis equal to pelvic incidence ± 9 degrees. Conclusion Sagittal plane malalignment is an increasingly recognized cause of pain and disability. Treatment of sagittal plane imbalance varies according to the etiology, location, and severity of the deformity. Fixed sagittal malalignment often requires complex reconstructive procedures that include osteotomy correction. Reestablishing harmonious spinopelvic alignment is associated with significant improvement in health-related quality-of-life outcome measures and patient satisfaction. PMID:25396111
23. DETAIL VIEW OF FIXED SPAN SUBSTRUCTURE, EAST SPAN, SHOWING ...
23. DETAIL VIEW OF FIXED SPAN SUBSTRUCTURE, EAST SPAN, SHOWING CONDITION OF GRANITE PIERS AND PILES OF ADJACENT PIER, LOOKING SOUTHEAST - Congress Street Bascule Bridge, Spanning Fort Point Channel at Congress Street, Boston, Suffolk County, MA
Point specificity in acupuncture
2012-01-01
The existence of point specificity in acupuncture is controversial, because many acupuncture studies using this principle to select control points have found that sham acupoints have similar effects to those of verum acupoints. Furthermore, the results of pain-related studies based on visual analogue scales have not supported the concept of point specificity. In contrast, hemodynamic, functional magnetic resonance imaging and neurophysiological studies evaluating the responses to stimulation of multiple points on the body surface have shown that point-specific actions are present. This review article focuses on clinical and laboratory studies supporting the existence of point specificity in acupuncture and also addresses studies that do not support this concept. Further research is needed to elucidate the point-specific actions of acupuncture. PMID:22373514
Using a Card Trick to Illustrate Fixed Points and Stability
ERIC Educational Resources Information Center
Champanerkar, Jyoti; Jani, Mahendra
2015-01-01
Mathematical ideas from number theory, group theory, dynamical systems, and computer science have often been used to explain card tricks. Conversely, playing cards have been often used to illustrate the mathematical concepts of probability distributions and group theory. In this paper, we describe how the 21-card trick may be used to illustrate
From fixed points to chaos: three models of delayed discrimination.
Barak, Omri; Sussillo, David; Romo, Ranulfo; Tsodyks, Misha; Abbott, L F
2013-04-01
Working memory is a crucial component of most cognitive tasks. Its neuronal mechanisms are still unclear despite intensive experimental and theoretical explorations. Most theoretical models of working memory assume both time-invariant neural representations and precise connectivity schemes based on the tuning properties of network neurons. A different, more recent class of models assumes randomly connected neurons that have no tuning to any particular task, and bases task performance purely on adjustment of network readout. Intermediate between these schemes are networks that start out random but are trained by a learning scheme. Experimental studies of a delayed vibrotactile discrimination task indicate that some of the neurons in prefrontal cortex are persistently tuned to the frequency of a remembered stimulus, but the majority exhibit more complex relationships to the stimulus that vary considerably across time. We compare three models, ranging from a highly organized line attractor model to a randomly connected network with chaotic activity, with data recorded during this task. The random network does a surprisingly good job of both performing the task and matching certain aspects of the data. The intermediate model, in which an initially random network is partially trained to perform the working memory task by tuning its recurrent and readout connections, provides a better description, although none of the models matches all features of the data. Our results suggest that prefrontal networks may begin in a random state relative to the task and initially rely on modified readout for task performance. With further training, however, more tuned neurons with less time-varying responses should emerge as the networks become more structured. PMID:23438479
Using a Card Trick to Illustrate Fixed Points and Stability
ERIC Educational Resources Information Center
Champanerkar, Jyoti; Jani, Mahendra
2015-01-01
Mathematical ideas from number theory, group theory, dynamical systems, and computer science have often been used to explain card tricks. Conversely, playing cards have been often used to illustrate the mathematical concepts of probability distributions and group theory. In this paper, we describe how the 21-card trick may be used to illustrate…
Hall, David R.; Bartholomew, David B.; Moon, Justin; Koehler, Roger O.
2009-09-08
An apparatus for fixing computational latency within a deterministic region on a network comprises a network interface modem, a high priority module and at least one deterministic peripheral device. The network interface modem is in communication with the network. The high priority module is in communication with the network interface modem. The at least one deterministic peripheral device is connected to the high priority module. The high priority module comprises a packet assembler/disassembler, and hardware for performing at least one operation. Also disclosed is an apparatus for executing at least one instruction on a downhole device within a deterministic region, the apparatus comprising a control device, a downhole network, and a downhole device. The control device is near the surface of a downhole tool string. The downhole network is integrated into the tool string. The downhole device is in communication with the downhole network.
NASA Astrophysics Data System (ADS)
Cornaglia, Bruno; Young, Gavin; Marchetta, Antonio
2015-12-01
Fixed broadband network deployments are moving inexorably to the use of Next Generation Access (NGA) technologies and architectures. These NGA deployments involve building fiber infrastructure increasingly closer to the customer in order to increase the proportion of fiber on the customer's access connection (Fibre-To-The-Home/Building/Door/Cabinet… i.e. FTTx). This increases the speed of services that can be sold and will be increasingly required to meet the demands of new generations of video services as we evolve from HDTV to "Ultra-HD TV" with 4k and 8k lines of video resolution. However, building fiber access networks is a costly endeavor. It requires significant capital in order to cover any significant geographic coverage. Hence many companies are forming partnerships and joint-ventures in order to share the NGA network construction costs. One form of such a partnership involves two companies agreeing to each build to cover a certain geographic area and then "cross-selling" NGA products to each other in order to access customers within their partner's footprint (NGA coverage area). This is tantamount to a bi-lateral wholesale partnership. The concept of Fixed Access Network Sharing (FANS) is to address the possibility of sharing infrastructure with a high degree of flexibility for all network operators involved. By providing greater configuration control over the NGA network infrastructure, the service provider has a greater ability to define the network and hence to define their product capabilities at the active layer. This gives the service provider partners greater product development autonomy plus the ability to differentiate from each other at the active network layer.
Genn Saji
2006-07-01
The author has investigated the characteristics of boron co-deposition with crud experienced in AOA and iron ferrite deposition in CDA. Corrosion product deposits found in cores with appreciable AOA have been reported in mostly nickel-based (as NiO or elemental nickel) as opposed to nickel ferrite deposits common to non-boiling cores. Significant quantities of meta-ZrO{sub 2} and nickel iron oxy-borates (bonaccordite), notably Ni{sub 2}FeBO{sub 5} have also been found in deposits on cores with AOA. On the basis of this general characterization information, the author has constructed a potential-pH diagram of Ni{sub 2}FeB(OH){sub 10}, which is a hydrated state of FeNi{sub 2}(BO{sub 3})O{sub 2} as summarized in this paper. Although preliminary, the estimated E-pH diagram suggests some interesting observation, including: growth of bonaccordite 'needles' on the clad is associated with a local anodic electrochemical reaction necessary to remove excess electrons from the system to a cathode. During the AOA cycle, the concentration of nickel and iron ions must have been unusually high as they should be for a significant amount of crud deposits. The author thinks such an acceleration of the anodic dissolution of metal cations is due to the effect of the long cell action corrosion mechanism. As early as 1949, an Italian scientist Petracchi demonstrated that electrochemical effects significantly influence the erosion rate. He constructed a flow nozzle with specimens kept under external electrical potential. Upon inducing as low as 0.1 mA/cm{sup 2} of the positive current, the erosion rates were reported drastically increased. No erosion was observed by reversing the polarity of the potential. As discussed in a companion paper also presented at this conference, the author discusses various mechanisms (electrochemical cell configurations) that induce potential differences, including those differences in ionic concentration, aeration, temperature, flow velocity, radiation and corrosion potentials. In this paper, the author discusses how these potential differences are related to the AOA/CDA issues in PWR/VVER plants. The author is calling for further verification experiments regarding this corrosion mechanism as a joint international project. (author)
Dogherty, Elizabeth J; Harrison, Margaret B; Graham, Ian D; Vandyk, Amanda Digel; Keeping-Burke, Lisa
2013-01-01
Background: Facilitation is considered a way of enabling clinicians to implement evidence into practice by problem solving and providing support. Practice development is a well-established movement in the United Kingdom that incorporates the use of facilitators, but in Canada, the role is more obtuse. Few investigations have observed the process of facilitation as described by individuals experienced in guideline implementation in North America. AimTo describe the tacit knowledge regarding facilitation embedded in the experiences of nurses implementing evidence into practice. Methods: Twenty nurses from across Canada were purposively selected to attend an interactive knowledge translation symposium to examine what has worked and what has not in implementing evidence in practice. This study is an additional in-depth analysis of data collected at the symposium that focuses on facilitation as an intervention to enhance evidence uptake. Critical incident technique was used to elicit examples to examine the nurses facilitation experiences. Participants shared their experiences with one another and completed initial data analysis and coding collaboratively. The data were further thematically analyzed using the qualitative inductive approach of constant comparison. Results: A number of factors emerged at various levels associated with the successes and failures of participants efforts to facilitate evidence-based practice. Successful implementation related to: (a) focus on a priority issue, (b) relevant evidence, (c) development of strategic partnerships, (d) the use of multiple strategies to effect change, and (e) facilitator characteristics and approach. Negative factors influencing the process were: (a) poor engagement or ownership, (b) resource deficits, (c) conflict, (d) contextual issues, and (e) lack of evaluation and sustainability. Conclusions: Factors at the individual, environmental, organizational, and cultural level influence facilitation of evidence-based practice in real situations at the point-of-care. With a greater understanding of factors contributing to successful or unsuccessful facilitation, future research should focus on analyzing facilitation interventions tailored to address barriers and enhance facilitators of evidence uptake. PMID:23796066
Colligative Properties of Solutions: I. Fixed Concentrations
NASA Astrophysics Data System (ADS)
Alexander, Kenneth S.; Biskup, Marek; Chayes, Lincoln
2005-05-01
Using the formalism of rigorous statistical mechanics, we study the phenomena of phase separation and freezing-point depression upon freezing of solutions. Specifically, we devise an Ising-based model of a solvent--solute system and show that, in the ensemble with a fixed amount of solute, a macroscopic phase separation occurs in an interval of values of the chemical potential of the solvent. The boundaries of the phase separation domain in the phase diagram are characterized and shown to asymptotically agree with the formulas used in heuristic analyses of freezing-point depression. The limit of infinitesimal concentrations is described in a subsequent paper.
Act of swallowing in the fixed larynx.
Krajina, Z; Vecerina, S
1976-01-01
In a 16-year-old female, complete stenosis of the larynx and hypopharynx developed as a consequence of the ingestion of lye cristals. Supraglotic laryngectomy, plastic surgery of the hypopharynx and antethoracic oesophagus were performed and the upper aero-digestive tract reconstructed. The dilated larynx remained fixed by the surrounding fibrous tissue, but the sphincteric action of the mobile vocal cords was partly salvaged. In that condition, the act of swallowing could be reestablished. The pathophysiology of this new mechanism of swallowing is discussed. PMID:1266619
"Wuwei" (Non-Action) Philosophy and Actions: Rethinking "Actions" in School Reform
ERIC Educational Resources Information Center
Moon, Seungho
2015-01-01
This inquiry aims to enrich conversation regarding school reform. The author asks about what other discourses are possible when the action-oriented question of how to "act" is a major approach to "fix" current educational problems. Drawing from Taoist philosophy of "wuwei" (non-action), the author provides a frame to…
"Wuwei" (Non-Action) Philosophy and Actions: Rethinking "Actions" in School Reform
ERIC Educational Resources Information Center
Moon, Seungho
2015-01-01
This inquiry aims to enrich conversation regarding school reform. The author asks about what other discourses are possible when the action-oriented question of how to "act" is a major approach to "fix" current educational problems. Drawing from Taoist philosophy of "wuwei" (non-action), the author provides a frame to
NASA Astrophysics Data System (ADS)
Young, Frederic; Siegel, Edward
Cook-Levin theorem theorem algorithmic computational-complexity(C-C) algorithmic-equivalence reducibility/completeness equivalence to renormalization-(semi)-group phase-transitions critical-phenomena statistical-physics universality-classes fixed-points, is exploited via Siegel FUZZYICS =CATEGORYICS = ANALOGYICS =PRAGMATYICS/CATEGORY-SEMANTICS ONTOLOGY COGNITION ANALYTICS-Aristotle ``square-of-opposition'' tabular list-format truth-table matrix analytics predicts and implements ''noise''-induced phase-transitions (NITs) to accelerate versus to decelerate Harel [Algorithmics (1987)]-Sipser[Intro.Thy. Computation(`97)] algorithmic C-C: ''NIT-picking''(!!!), to optimize optimization-problems optimally(OOPO). Versus iso-''noise'' power-spectrum quantitative-only amplitude/magnitude-only variation stochastic-resonance, ''NIT-picking'' is ''noise'' power-spectrum QUALitative-type variation via quantitative critical-exponents variation. Computer-''science''/SEANCE algorithmic C-C models: Turing-machine, finite-state-models, finite-automata,..., discrete-maths graph-theory equivalence to physics Feynman-diagrams are identified as early-days once-workable valid but limiting IMPEDING CRUTCHES(!!!), ONLY IMPEDE latter-days new-insights!!!
Fixed site hydrogen storage. I - Applications impact
NASA Astrophysics Data System (ADS)
Iannucci, J. J.; Robinson, S. L.
The potential applications and requirements for fixed site storage in a scenario of wide spread hydrogen use are examined and quantified. An envisioned hydrogen production/distribution/end-use cycle is scrutinized to identify the storage needs for both continuous and intermittent sources including solar. The most pressing need for storage is found to be at the distribution point, in concurrence with current natural gas practice. Caverns and similar underground storage techniques are shown to be the most promising modes due to their low cost relative to all other options examined. Since a large volume of natural gas storage is presently in service, a pressing need to develop fixed site hydrogen storage technology (beyond the conversion of this underground storage to hydrogen) has not been identified.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-11-27
... From the Federal Register Online via the Government Publishing Office NUCLEAR REGULATORY COMMISSION Entergy Nuclear Indian Point 2, LLC; Entergy Nuclear Operations, Inc., Indian Point Nuclear Generating Unit No. 2, Request for Action AGENCY: Nuclear Regulatory Commission. ACTION: Request for...
Action and entanglement in gravity and field theory.
Neiman, Yasha
2013-12-27
In nongravitational quantum field theory, the entanglement entropy across a surface depends on the short-distance regularization. Quantum gravity should not require such regularization, and it has been conjectured that the entanglement entropy there is always given by the black hole entropy formula evaluated on the entangling surface. We show that these statements have precise classical counterparts at the level of the action. Specifically, we point out that the action can have a nonadditive imaginary part. In gravity, the latter is fixed by the black hole entropy formula, while in nongravitating theories it is arbitrary. From these classical facts, the entanglement entropy conjecture follows by heuristically applying the relation between actions and wave functions. PMID:24483789
Action and Entanglement in Gravity and Field Theory
NASA Astrophysics Data System (ADS)
Neiman, Yasha
2013-12-01
In nongravitational quantum field theory, the entanglement entropy across a surface depends on the short-distance regularization. Quantum gravity should not require such regularization, and it has been conjectured that the entanglement entropy there is always given by the black hole entropy formula evaluated on the entangling surface. We show that these statements have precise classical counterparts at the level of the action. Specifically, we point out that the action can have a nonadditive imaginary part. In gravity, the latter is fixed by the black hole entropy formula, while in nongravitating theories it is arbitrary. From these classical facts, the entanglement entropy conjecture follows by heuristically applying the relation between actions and wave functions.
Fixed drug eruption from pamabrom.
Nedorost, S; Taylor, J S; Camisa, C; Tomecki, K J; Helm, T; Durkin, W J
1991-01-01
A young woman presented with recurrent skin lesions that were predominantly perioral. Fixed drug reaction was diagnosed based on her history of intermittent ingestion of Pamprin, a common menstrual symptom reliever, and characteristic erythematous, pigmented, edematous patches. After oral challenge with two of the three ingredients in Pamprin, a diagnosis of fixed drug reaction to pamabrom was made. Pamabrom is a mild diuretic present in several over-the-counter and prescription menstrual symptom relievers. This is the first reported case of fixed drug reaction to pamabrom. PMID:1829985
Total effective dose equivalent associated with fixed uranium surface contamination
Bogard, J.S.; Hamm, R.N.; Ashley, J.C.; Turner, J.E.; England, C.A.; Swenson, D.E.; Brown, K.S.
1997-04-01
This report provides the technical basis for establishing a uranium fixed-contamination action level, a fixed uranium surface contamination level exceeding the total radioactivity values of Appendix D of Title 10, Code of Federal Regulations, part 835 (10CFR835), but below which the monitoring, posting, and control requirements for Radiological Areas are not required for the area of the contamination. An area of fixed uranium contamination between 1,000 dpm/100 cm{sup 2} and that level corresponding to an annual total effective dose equivalent (TEDE) of 100 mrem requires only routine monitoring, posting to alert personnel of the contamination, and administrative control. The more extensive requirements for monitoring, posting, and control designated by 10CFR835 for Radiological Areas do not have to be applied for these intermediate fixed-contamination levels.
Why to treat subjects as fixed effects.
Adelman, James S; Estes, Zachary
2015-09-01
Adelman, Marquis, Sabatos-DeVito, and Estes (2013) collected word naming latencies from 4 participants who read 2,820 words 50 times each. Their recommendation and practice was that R² targets set for models should take into account subject idiosyncrasies as replicable patterns, equivalent to a subjects-as-fixed-effects assumption. In light of an interaction involving subjects, they broke down the interaction into individual subject data. Courrieu and Rey's (2015) commentary argues that (a) single-subject data need not be more reliable than subject-average data, and (b) anyway, treating groups of subjects as random samples leads to valid conclusions about general mechanisms of reading. Point (a) was not part of Adelman et al.'s claim. In this reply, we examine the consequences of using the fixed-effect assumption. It (a) produces the correct target to check if by-items regression models contain all necessary variables, (b) more accurately constrains cognitive models, (c) more accurately reveals general mechanisms, and (d) can offer more powerful tests of effects. Even when individual differences are not the primary focus of a study, the fixed-effect analysis is often preferable to the random-effects analysis. PMID:26348203
NASA Astrophysics Data System (ADS)
Hamada, Yuta; Kawai, Hikaru; Kawana, Kiyoharu
2014-06-01
We give an evidence of the Big Fix. The theory of wormholes and multiverse suggests that the parameters of the Standard Model are fixed in such a way that the total entropy at the late stage of the universe is maximized, which we call the maximum entropy principle. In this paper, we discuss how it can be confirmed by the experimental data, and we show that it is indeed true for the Higgs vacuum expectation value vh. We assume that the baryon number is produced by the sphaleron process, and that the current quark masses, the gauge couplings and the Higgs self-coupling are fixed when we vary vh. It turns out that the existence of the atomic nuclei plays a crucial role to maximize the entropy. This is reminiscent of the anthropic principle, however it is required by the fundamental law in our case.
Liminality as Thought and Action
ERIC Educational Resources Information Center
Emmanuel, Donna T.
2011-01-01
Turner's (1974) conception of liminal space provides an entry point to look beyond the given and to create opportunities to examine, critique, and challenge the assumptions inherent in many music programs. Building upon his theory of liminality as a place that is "ambiguous, neither here or there, betwixt and between all fixed points of…
Rosenbaum, David A.; Chapman, Kate M.; Coelho, Chase J.; Gong, Lanyun; Studenka, Breanna E.
2013-01-01
Actions that are chosen have properties that distinguish them from actions that are not. Of the nearly infinite possible actions that can achieve any given task, many of the unchosen actions are irrelevant, incorrect, or inappropriate. Others are relevant, correct, or appropriate but are disfavored for other reasons. Our research focuses on the question of what distinguishes actions that are chosen from actions that are possible but are not. We review studies that use simple preference methods to identify factors that contribute to action choices, especially for object-manipulation tasks. We can determine which factors are especially important through simple behavioral experiments. PMID:23761769
NASA Astrophysics Data System (ADS)
Cardoso, Nuno; Silva, Paulo J.; Bicudo, Pedro; Oliveira, Orlando
2013-01-01
In this paper we present and explore the performance of Landau gauge fixing in GPUs using CUDA. We consider the steepest descent algorithm with Fourier acceleration, and compare the GPU performance with a parallel CPU implementation. Using 324 lattice volumes, we find that the computational power of a single Tesla C2070 GPU is equivalent to approximately 256 CPU cores.
Fixed Costs and Hours Constraints
ERIC Educational Resources Information Center
Johnson, William R.
2011-01-01
Hours constraints are typically identified by worker responses to questions asking whether they would prefer a job with more hours and more pay or fewer hours and less pay. Because jobs with different hours but the same rate of pay may be infeasible when there are fixed costs of employment or mandatory overtime premia, the constraint in those…
Curricular Guidelines in Fixed Prosthodontics.
ERIC Educational Resources Information Center
Brindsen, Gilbert; And Others
1984-01-01
The American Association of Dental Schools' guidelines for curriculum development in fixed prosthodontics outline the scope of the subject, interrelationship with other subjects and specialties, primary educational goals, prerequisites, core content, specific behavioral objectives for each subarea, sequencing, and faculty requirements. (MSE)
Sigma model renormalization group flow, 'central charge' action, and Perelman's entropy
Tseytlin, A. A.
2007-03-15
Zamolodchikov's c-theorem type argument (and also string theory effective action constructions) imply that the RG flow in 2d sigma model should be a gradient one to all loop orders. However, the monotonicity of the flow of the target-space metric is not obvious since the metric on the space of metric-dilaton couplings is indefinite. To leading (one-loop) order when the RG flow is simply the Ricci flow the monotonicity was proved by Perelman [G. Perelman, math.dg/0211159.] by constructing an 'entropy' functional which is essentially the metric-dilaton action extremized with respect to the dilaton with a condition that the target-space volume is fixed. We discuss how to generalize the Perelman's construction to all loop orders (i.e. all orders in {alpha}{sup '}). The resulting entropy is equal to minus the central charge at the fixed points, in agreement with the general claim of the c-theorem.
NASA Astrophysics Data System (ADS)
Hansen, J.
2007-12-01
A climate tipping point, at least as I have used the phrase, refers to a situation in which a changing climate forcing has reached a point such that little additional forcing (or global temperature change) is needed to cause large, relatively rapid, climate change. Present examples include potential loss of all Arctic sea ice and instability of the West Antarctic and Greenland ice sheets. Tipping points are characterized by ready feedbacks that amplify the effect of forcings. The notion that these may be runaway feedbacks is a misconception. However, present "unrealized" global warming, due to the climate system's thermal inertia, exacerbates the difficulty of avoiding global warming tipping points. I argue that prompt efforts to slow CO2 emissions and absolutely reduce non-CO2 forcings are both essential if we are to avoid tipping points that would be disastrous for humanity and creation, the planet as civilization knows it.
Nonquadratic gauge fixing and ghosts for gauge theories on the hypersphere
Brandt, F. T.; McKeon, D. G. C.
2011-10-15
It has been suggested that using a gauge fixing Lagrangian that is not quadratic in a gauge fixing condition is most appropriate for gauge theories formulated on a hypersphere. We reexamine the appropriate ghost action that is to be associated with gauge fixing, applying a technique that has been used for ensuring that the propagator for a massless spin-two field is transverse and traceless. It is shown that this nonquadratic gauge fixing Lagrangian leads to two pair of complex Fermionic ghosts and two Bosonic real ghosts.
Nonquadratic gauge fixing and ghosts for gauge theories on the hypersphere
NASA Astrophysics Data System (ADS)
Brandt, F. T.; McKeon, D. G. C.
2011-10-01
It has been suggested that using a gauge fixing Lagrangian that is not quadratic in a gauge fixing condition is most appropriate for gauge theories formulated on a hypersphere. We reexamine the appropriate ghost action that is to be associated with gauge fixing, applying a technique that has been used for ensuring that the propagator for a massless spin-two field is transverse and traceless. It is shown that this nonquadratic gauge fixing Lagrangian leads to two pair of complex Fermionic ghosts and two Bosonic real ghosts.
Variable delivery, fixed displacement pump
Sommars, Mark F.
2001-01-01
A variable delivery, fixed displacement pump comprises a plurality of pistons reciprocated within corresponding cylinders in a cylinder block. The pistons are reciprocated by rotation of a fixed angle swash plate connected to the pistons. The pistons and cylinders cooperate to define a plurality of fluid compression chambers each have a delivery outlet. A vent port is provided from each fluid compression chamber to vent fluid therefrom during at least a portion of the reciprocal stroke of the piston. Each piston and cylinder combination cooperates to close the associated vent port during another portion of the reciprocal stroke so that fluid is then pumped through the associated delivery outlet. The delivery rate of the pump is varied by adjusting the axial position of the swash plate relative to the cylinder block, which varies the duration of the piston stroke during which the vent port is closed.
Logan, Gordon D.
2015-01-01
Bartlett (1958) described the point of no return as a point of irrevocable commitment to action, which was preceded by a period of gradually increasing commitment. As such, the point of no return reflects a fundamental limit on the ability to control thought and action. I review the literature on the point of no return, taking three perspectives. First, I consider the point of no return from the perspective of the controlled act, as a locus in the architecture and anatomy of the underlying processes. I review experiments from the stop-signal paradigm that suggest that the point of no return is located late in the response system. Then I consider the point of no return from the perspective of the act of control that tries to change the controlled act before it becomes irrevocable. From this perspective, the point of no return is a point in time that provides enough “lead time” for the act of control to take effect. I review experiments that measure the response time to the stop signal as the lead time required for response inhibition in the stop-signal paradigm. Finally, I consider the point of no return in hierarchically controlled tasks, in which there may be many points of no return at different levels of the hierarchy. I review experiments on skilled typing that suggest different points of no return for the commands that determine what is typed and the countermands that inhibit typing, with increasing commitment to action the lower the level in the hierarchy. I end by considering the point of no return in perception and thought as well as action. PMID:25633089
MedlinePlus Videos and Cool Tools
... Tipping Point by CPSC Blogger September 22 appliance child Childproofing CPSC danger death electrical fall furniture head ... TV falls with about the same force as child falling from the third story of a building. ...
Partial gauge fixing and equivariant cohomology
NASA Astrophysics Data System (ADS)
Ferrari, Frank
2014-05-01
Given a gauge theory with gauge group G, it is sometimes useful to find an equivalent formulation in terms of a nontrivial gauge subgroup H ⊂G. This amounts to fixing the gauge partially from G down to H. We study this problem systematically, both from the algebraic and from the path integral points of view. We find that the usual BRST cohomology must be replaced by an equivariant version and that the ghost Lagrangian must always include quartic ghost terms, even at tree level. Both the Cartan and Weil models for equivariant cohomology play a role and find natural interpretations within the physics framework. Applications include the construction of D-brane models of emergent space, the 't Hooft Abelian projection scenario in quantum chromodynamics and the formulation of the low-energy effective theories of grand unified models.
Covariant computation of effective actions in Hořava-Lifshitz gravity
NASA Astrophysics Data System (ADS)
D'Odorico, Giulio; Goossens, Jan-Willem; Saueressig, Frank
2015-10-01
We initiate the systematic computation of the heat-kernel coefficients for Laplacian operators obeying anisotropic dispersion relations in curved spacetime. Our results correctly reproduce the limit where isotropy is restored and special anisotropic cases considered previously in the literature. Subsequently, the heat kernel is used to derive the scalar-induced one-loop effective action and beta functions of Hořava-Lifshitz gravity. We identify the Gaussian fixed point which is supposed to provide the UV completion of the theory. In the present setting, this fixed point acts as an infrared attractor for the renormalization group flow of Newton's constant and the high-energy phase of the theory is screened by a Landau pole. We comment on the consequences of these findings for the renormalizability of the theory.
Sartori, Luisa; Betti, Sonia
2015-01-01
Complementary colors are color pairs which, when combined in the right proportions, produce white or black. Complementary actions refer here to forms of social interaction wherein individuals adapt their joint actions according to a common aim. Notably, complementary actions are incongruent actions. But being incongruent is not sufficient to be complementary (i.e., to complete the action of another person). Successful complementary interactions are founded on the abilities: (i) to simulate another person’s movements, (ii) to predict another person’s future action/s, (iii) to produce an appropriate incongruent response which differ, while interacting, with observed ones, and (iv) to complete the social interaction by integrating the predicted effects of one’s own action with those of another person. This definition clearly alludes to the functional importance of complementary actions in the perception–action cycle and prompts us to scrutinize what is taking place behind the scenes. Preliminary data on this topic have been provided by recent cutting-edge studies utilizing different research methods. This mini-review aims to provide an up-to-date overview of the processes and the specific activations underlying complementary actions. PMID:25983717
The triple point of sulfur hexafluoride
NASA Astrophysics Data System (ADS)
Rourke, P. M. C.
2016-04-01
A cryogenic fixed point cell has been filled with high purity (99.999%) sulfur hexafluoride (SF6) and measured in an adiabatic closed-cycle cryostat system. Temperature measurements of the SF6 melting curve were performed using a capsule-type standard platinum resistance thermometer (CSPRT) calibrated over the International Temperature Scale of 1990 (ITS-90) subrange from the triple point of equilibrium hydrogen to the triple point of water. The measured temperatures were corrected by 0.37 mK for the effects of thermometer self-heating, and the liquidus-point temperature estimated by extrapolation to melted fraction F = 1 of a simple linear regression versus melted fraction F in the range F = 0.53 to 0.84. Based on this measurement, the temperature of the triple point of sulfur hexafluoride is shown to be 223.555 23(49) K (k = 1) on the ITS-90. This value is in excellent agreement with the best prior measurements reported in the literature, but with considerably smaller uncertainty. An analysis of the detailed uncertainty budget of this measurement suggests that if the triple point of sulfur hexafluoride were to be included as a defining fixed point of the next revision of the International Temperature Scale, it could do so with a total realization uncertainty of approximately 0.43 mK, slightly larger than the realization uncertainties of the defining fixed points of the ITS-90. Since the combined standard uncertainty of this SF6 triple point temperature determination is dominated by chemical impurity effects, further research exploring gas purification techniques and the influence of specific impurity species on the SF6 triple point temperature may bring the realization uncertainty of SF6 as a fixed point material into the range of the defining fixed points of the ITS-90.
Sorensen, J.H.
1988-04-01
This is a preliminary evaluation of warning systems and protective action options for off-site emergency planning for chemical weapons accidents. The analysis concentrates on the timing of warning and protective action implementation which is defined as the length of time it will take to protect off-site populations given different warning systems and protective action configurations. The evaluation concludes: (1) A specialized warning system using tone alert radios, automatic telephone dialing systems, sirens, or some combination thereof is desirable within 10 km of the fixed sites. (2) A rapid means of respiratory protection and expedient protective sheltering are the protective actions that could be most rapidly implemented within 10 km of a fixed-site release point. (3) Populations at distances greater than 10 km should have time to evacuate without the installation of specialized warning systems except in institutional facilities such as schools and nursing homes. (4) The detection and warning decision times are critical elements in determining the feasibility of population protection. A 5-to-15-minute organizational response is needed to provide warning to potentially threatened populations. Even an expedient organizational response, however, will not provide 100% assurance that everyone will have time to learn of the accident and take action. 9 refs., 4 tabs.
Comparison of slurry versus fixed-bed reactor costs for indirect liquefaction applications
Prakash, A.; Bendale, P.G.
1991-12-01
This work is a comparative evaluation of slurry reactors and fixed-bed reactors, with special emphasis on cost. Relative differences between slurry reactors and fixed-bed reactors have been pointed out in previous reviews; the differences pertinent to indirect liquefaction are summarized here. Design of both types is outlined.
Experimental designs for mixtures of chemicals along fixed ratio rays.
Meadows, Stephanie L; Gennings, Chris; Carter, W Hans; Bae, Dong-Soon
2002-01-01
Experimental design is important when studying mixtures/combinations of chemicals. The traditional approach for studying mixtures/combinations of multiple chemicals involves response surface methodology, often supported by factorial designs. Although such an approach permits the investigation of both the effects of individual chemicals and their interactions, the number of design points needed to study the chemical mixtures becomes prohibitive when the number of compounds increases. Fixed ratio ray designs have been developed to reduce the amount of experimental effort when interest can be restricted to a specific ray. We focus on the design and analysis issues involved in studying mixtures/combinations of compounds along fixed ratio rays of the compounds. To obtain the inference regarding the interactions among the compounds, we show that the only data required are those along the fixed ratio ray. PMID:12634128
ERIC Educational Resources Information Center
1996
These four papers were presented at a symposium on action learning moderated by Lex Dilworth at the 1996 conference of the Academy of Human Resource Development. "Developing an Infrastructure for Individual and Organizational Change: Transfer of Learning from an Action Reflection Learning (ARL) Program" (ARL Inquiry) reports findings from a study
STAR Au + Au Fixed Target Results
NASA Astrophysics Data System (ADS)
Meehan, Kathryn; STAR Collaboration
2015-10-01
The RHIC Beam Energy Scan (BES) program was proposed to look for the turn-off of signatures of the quark gluon plasma (QGP), search for a possible QCD critical point, and study the nature of the phase transition between hadronic and partonic matter. The results from the NA49 experiment at CERN have been used to claim that the onset of deconfinement occurs at a collision energy around a center-of-mass energy of 7 GeV, the low end of the BES range. Data from lower energies are needed to test if this onset occurs. The goal of the STAR Fixed-Target Program is to extend the collision energy range in BES II with the same detector to energies that are likely below the onset of deconfinement. Currently, STAR has inserted a gold target into the beam pipe and conducted test runs at center-of-mass energies 3.9 and 4.5 GeV. Tests have been done with both Au and Al beams. First physics results from a Coulomb analysis of Au + Au fixed-target collisions, which are found to be consistent with previous experiments, will be presented. These results demonstrate that STAR has good particle identification capabilities in this novel detector setup. Furthermore, the Coulomb potential, which is sensitive to the Z of the projectile and degree of baryonic stopping, will be compared with published results from the AGS. This material is based upon work supported by the National Science Foundation under Grant No. 1068833.
Global Positioning System Antenna Fixed Height Tripod Adapter
NASA Technical Reports Server (NTRS)
Dinardo, Steven J.; Smith, Mark A.
1997-01-01
An improved Global Positioning em antenna adaptor allows fixed antenna height measurements by removably attaching an adaptor plate to a conventional surveyor's tripod. Antenna height is controlled by an antenna boom which is a fixed length rod. The antenna is attached to one end of the boom. The opposite end of the boom tapers to a point sized to fit into a depression at the center of survey markers. The boom passes through the hollow center of a universal ball joint which is mounted at the center of the adaptor plate so that the point of the rod can be fixed in the marker's central depression. The mountains of the ball joint allow the joint to be moved horizontally in any direction relative to the tripod. When the ball joint is moved horizontally, the angle between the boom and the vertical changes because the boom's position is fixed at its lower end. A spirit level attached to the rod allows an operator to determine when the boom is plumb. The position of the ball joint is adjusted horizontally until the boom is plumb. At that time the antenna is positioned exactly over the center of the monument and the elevation of the antenna is precisely set by the length of the boom.
Simple Fixed Functional Space Maintainer
Sarawgi, Aditi; Marwah, Nikhil; Gumber, Parvind; Dutta, Samir
2014-01-01
ABSTRACT% Premature loss of a primary tooth is one of the most common etiology for malocclusion. Space maintainers are employed to prevent this complication. In anterior region, esthetics is an important concern along with function and space management. Fiber-reinforced composite (FRC) retained space maintainer solves all these purposes ef ficiently and ef fectively. In addition, the technique is simple and the appliance is very comfortable inside the oral cavity. Here is a case of premature loss of anterior primary tooth which was replaced by FRC retained esthetic functional space maintainer. The appliance was found to be functioning satisfactorily inside the oral cavity till the last visit (1 Year). How to cite this article: Goenka P, Sarawgi A, Marwah N, Gumber P, Dutta S. Simple Fixed Functional Space Maintainer. Int J Clin Pediatr Dent 2014;7(3):225-228. PMID:25709309
NASA Technical Reports Server (NTRS)
Yam, Y.; Briggs, C.
1988-01-01
One important aspect of the LDR control problem is the possible excitations of structural modes due to random disturbances, mirror chopping, and slewing maneuvers. An analysis was performed to yield a first order estimate of the effects of such dynamic excitations. The analysis involved a study of slewing jitters, chopping jitters, disturbance responses, and pointing errors, making use of a simplified planar LDR model which describes the LDR dynamics on a plane perpendicular to the primary reflector. Briefly, the results indicate that the command slewing profile plays an important role in minimizing the resultant jitter, even to a level acceptable without any control action. An optimal profile should therefore be studied.
A New Look at Trigger Point Injections
Wong, Clara S. M.; Wong, Steven H. S.
2012-01-01
Trigger point injections are commonly practised pain interventional techniques. However, there is still lack of objective diagnostic criteria for trigger points. The mechanisms of action of trigger point injection remain obscure and its efficacy remains heterogeneous. The advent of ultrasound technology in the noninvasive real-time imaging of soft tissues sheds new light on visualization of trigger points, explaining the effect of trigger point injection by blockade of peripheral nerves, and minimizing the complications of blind injection. PMID:21969825
NASA Astrophysics Data System (ADS)
Aragone, C.
1986-12-01
An action is presented for the free bosonic string on external flat space in terms of an antisymmetric second-rank string background tensor which is classically equivalent to the Nambu-Goto action. Both action and field equations are entirely described in terms of 2D world-sheet forms, without any reference to a 2D metric tensor background. The analysis of its canonical formulation shows how the quadratic Virasoro constraints are generated in this case and what their connection with the Bianchi identities are. Since in the orthonormal gauge the reduced action coincides with the standard one, it has the same critical dimension D = 26. The existence of an interaction term of a purely geometric structure stemming in the extrinsic curvature is pointed out. Its action and the new string field equations are then derived. This polynomial antisymmetric string action is uniformly generalized in order to describe d < D-dimensional extended objects in D-dimensional flat space. On leave of absence from Departamento de Física, Universidad Simon Bolívar, Apartado 80659, Caracas 1080A, Venezuela.
Action perception predicts action performance
Bailey, Heather R.; Kurby, Christopher A.; Giovannetti, Tania; Zacks, Jeffrey M.
2013-01-01
Everyday action impairments often are observed in demented older adults, and they are common potential barriers to functional independence. We evaluated whether the ability to segment and efficiently encode activities is related to the ability to execute activities. Further, we evaluated whether brain regions important for segmentation also were important for action performance. Cognitively healthy older adults and those with very mild or mild dementia of the Alzheimer's type watched and segmented movies of everyday activities and then completed the Naturalistic Action Test. Structural MRI was used to measure volume in the dorsolateral prefrontal cortex (DLPFC), medial temporal lobes (MTL), posterior cortex, and anterior cingulate cortex (ACC). Dementia status and the ability to segment everyday activities strongly predicted naturalistic action performance, and MTL volume largely accounted for this relationship. In addition, the current results supported the Omission-Commission Model: Different cognitive and neurological mechanisms predicted different types of action error. Segmentation, dementia severity, and MTL volume predicted everyday omission errors, DLPFC volume predicted commission errors, and ACC volume predicted action additions. These findings suggest that event segmentation may be critical for effective action production, and that the segmentation and production of activities may recruit the same event representation system. PMID:23851113
Fixed drug eruptions with modafinil
Ghoshal, Loknath; Sinha, Mausumi
2015-01-01
Modafinil is a psychostimulant drug, which has been approved by the US Food and Drug Administration for the treatment of narcolepsy associated excessive daytime sleepiness, sleep disorder related to shift work, and obstructive sleep apnea syndrome. However, presently it is being used as a lifestyle medicine; in India, it has been misused as an “over the counter” drug. Modafinil is known to have several cutaneous side effects. Fixed drug eruption (FDE) is a distinctive drug induced reaction pattern characterized by recurrence of eruption at the same site of the skin or mucous membrane with repeated systemic administration. Only two case reports exist in the literature describing modafinil induced FDE until date. Here, we report two similar cases. The increasing use of this class of drug amongst the medical personnel might be posing a threat to the proper use and encouraging subsequent abuse. There might be a considerable population using these drugs unaware of the possible adverse effects. Authorities should be more alert regarding the sale and distribution of such medicines. PMID:25878389
Chen, J.M.; Lim, B.S.; Al-Ghusain, I.A.; Hao, O.J.; Lin, C.F.; Davis, A.P.; Kim, M.H.; Huang, J.
1993-06-01
This paper includes reports on several biological fixed film systems in wastewater and hazardous waste treatment. Biological treatment of a refinery wastewater was studied in a rotating biological contactor (RBC) unit coupled with polyurethane foam (PUF) as a porous biomass support attached on both sides of the biodisks. The RBC-PUF bioreactor exhibited better performance than conventional RBCs for the removal of chemical oxygen demand (COD), NH{sub 3}-N, phenol, hydrocarbons, and suspended solids because of higher concentrations of active biomass. Successful performance of an anaerobic-aerobic treatment process using a combination of RCBs with activated sludge was achieved for treating a dye wastewater. Two high-rate trickling filters, cross-flow (CF) and vertical flow, were examined over a two year period for biological treatment of seafood processing wastewater. Results suggested superior performance of CF plastic media with substrate removal following a pseudo half-order kinetic reaction. Submerged structured packings in biofilm reactors were tested and characterized for a wide range of applications. Their efficiency was discussed in terms of contaminant removals and SS retention.
Fixed drug eruptions with modafinil.
Ghoshal, Loknath; Sinha, Mausumi
2015-01-01
Modafinil is a psychostimulant drug, which has been approved by the US Food and Drug Administration for the treatment of narcolepsy associated excessive daytime sleepiness, sleep disorder related to shift work, and obstructive sleep apnea syndrome. However, presently it is being used as a lifestyle medicine; in India, it has been misused as an "over the counter" drug. Modafinil is known to have several cutaneous side effects. Fixed drug eruption (FDE) is a distinctive drug induced reaction pattern characterized by recurrence of eruption at the same site of the skin or mucous membrane with repeated systemic administration. Only two case reports exist in the literature describing modafinil induced FDE until date. Here, we report two similar cases. The increasing use of this class of drug amongst the medical personnel might be posing a threat to the proper use and encouraging subsequent abuse. There might be a considerable population using these drugs unaware of the possible adverse effects. Authorities should be more alert regarding the sale and distribution of such medicines. PMID:25878389
Seven lean years. [No quick fix available
Byron, C.
1980-12-22
The end of the cheap oil era is having a more profound impact than any other single issue or event since World War II, making the everything crisis a more-appropriate label than energy crisis. Warnings from OPEC that oil may rise to $60 per barrel will not have worldwide inventories as a moderating force because the Iran-Iraq war has reduced OPEC production to the point where oil companies are unwilling to draw down their stockpiles. The cartel's prices have merely exploited a worldwide increase in demand for oil that would have pushed prices up anyway. The social and economic havoc is straining the economies of developed countries and could bankrupt and destabilize much of the Third World. The search for non-OPEC oil sources and alternatives to oil prompted a global race to discover new reserves, exploit renewable fuel sources, and initiate conservation. With no quick fix available, a painful period is foreseen while people learn to husband natural resources. (DCK)
Moreira, João A; Pinheiro, Flávio L; Nunes, Ana; Pacheco, Jorge M
2012-04-01
Many actions take some time to have an impact - their effects only appear at some point in the future. Such time lags turn out to be ubiquitous among living organisms. Here we study the impact of time lags in the evolutionary dynamics of cooperative collective action. We consider a population in which individuals interact via a N-Person Stag Hunt dilemma and must opt to cooperate or defect. In the absence of any delay, the replicator dynamics reveals the existence of regimes in which two internal fixed points appear simultaneously. We show that the presence of time delay in the fitness of individuals leads to a delayed replicator equation exhibiting new evolutionary profiles, each profile being separated by critical values of the delay that we determine explicitly. When we break the symmetry in the time lags, we show that, generally, defectors take more advantage from delay than cooperators. Finally, when we take into consideration, approximately, effects associated with the finite population size, we find that counter-intuitive evolutionary outcomes may occur, resulting from the interplay between delay and the basins of attraction in the neighborhood of the internal fixed-points, and which may lead to full cooperation in conditions under which the outcome would be Full Defection in infinite populations. PMID:22245522
Updraft Fixed Bed Gasification Aspen Plus Model
2007-09-27
The updraft fixed bed gasification model provides predictive modeling capabilities for updraft fixed bed gasifiers, when devolatilization data is available. The fixed bed model is constructed using Aspen Plus, process modeling software, coupled with a FORTRAN user kinetic subroutine. Current updraft gasification models created in Aspen Plus have limited predictive capabilities and must be "tuned" to reflect a generalized gas composition as specified in literature or by the gasifier manufacturer. This limits the applicability of the process model.
Aeroelastic Fixed Wing Micro Air Vehicle
NASA Technical Reports Server (NTRS)
2000-01-01
Wind tunnel testing of the University of Florida Aeroelastic Fixed Wing Micro Air Vehicle, biologically inspired flight systems. Photographed in building 1214, Basic Aerodynamics Research Tunnel (BART).
Software Faults Fixing Effort: Analysis and Prediction
NASA Technical Reports Server (NTRS)
Hamill, Maggie; Goseva-Popstojanova, Katerina
2014-01-01
Software developers spend significant amount of their time fixing faults. However, not many papers have addressed the effort needed to fix software faults. This paper is focused on comprehensive analysis of the fix implementation effort and factors that affect it, as well as on predicting the level of effort based on information recorded in software change requests. The work is based on data related to 1200 failures, extracted from the change tracking system of a large NASA mission. Our results show that (1) 83% of the total fix implementation effort was associated with only 20% of failures. (2) Both safety critical failures and post-release failures required three times more effort to fix compared to non-critical and pre-release counterparts, respectively. (3) Failures with fixes spread across multiple components and/or across multiple types of software artifacts required more effort. The spread across artifacts was more costly than spread across components. (4) Surprisingly, some types of faults associated with later life-cycle did not require significant effort, especially if only one type of artifact was fixed. (5) The level of fix implementation effort was predicted with 73% accuracy. The medium level fix implementation effort was classified more successfully than both low and high levels.
Final consolidated action plan to Tiger Team
Not Available
1992-10-01
This document contains the planned actions to correct the deficiences identified in the Tiger Team Assessments of Sandia California (August 1990) and Sandia New Mexico (May 1991). Information is also included on the management structures, estimated costs, root causes, prioritization and schedules for the Action Plan. This Plan is an integration of the two individual Action Plans to provide a cost effective, integrated program for implementation by Sandia and monitoring by DOE. This volume (I) contains the findings and actions concerning the environment. Tables 4.2 and 4.7 summarize the annual costs estimated for completing the actions. The total costs for completion of all the actions are estimated to be $283 million over a 12 year period; the majority of the actions to be completed and costs incurred in the first five years. Resources are provided from DOE-ER/WM, the DOE/DP landlord funds (one time, physical fixes), and from the Sandia Indirect Budget.
NASA Astrophysics Data System (ADS)
Zvizdic, Davor; Veliki, Tomislav; Grgec Bermanec, Lovorka
2008-06-01
This article describes the realization of the International Temperature Scale in the range from 234.3 K (mercury triple point) to 1084.62°C (copper freezing point) at the Laboratory for Process Measurement (LPM), Faculty of Mechanical Engineering and Naval Architecture (FSB), University of Zagreb. The system for the realization of the ITS-90 consists of the sealed fixed-point cells (mercury triple point, water triple point and gallium melting point) and the apparatus designed for the optimal realization of open fixed-point cells which include the gallium melting point, tin freezing point, zinc freezing point, aluminum freezing point, and copper freezing point. The maintenance of the open fixed-point cells is described, including the system for filling the cells with pure argon and for maintaining the pressure during the realization.
47 CFR 22.603 - 488-494 MHz fixed service in Hawaii.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 47 Telecommunication 2 2010-10-01 2010-10-01 false 488-494 MHz fixed service in Hawaii. 22.603 Section 22.603 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Paging and Radiotelephone Service Point-To-Point Operation § 22.603 488-494...
Optimal mixing and optimal stirring for fixed energy, fixed power, or fixed palenstrophy flows
NASA Astrophysics Data System (ADS)
Lunasin, Evelyn; Lin, Zhi; Novikov, Alexei; Mazzucato, Anna; Doering, Charles R.
2012-11-01
We consider passive scalar mixing by a prescribed divergence-free velocity vector field in a periodic box and address the following question: Starting from a given initial inhomogeneous distribution of passive tracers, and given a certain energy budget, power budget, or finite palenstrophy budget, what incompressible flow field best mixes the scalar quantity? We focus on the optimal stirring strategy recently proposed by Lin et al. ["Optimal stirring strategies for passive scalar mixing," J. Fluid Mech. 675, 465 (2011)], 10.1017/S0022112011000292 that determines the flow field that instantaneously maximizes the depletion of the H-1 mix-norm. In this work, we bridge some of the gap between the best available a priori analysis and simulation results. After recalling some previous analysis, we present an explicit example demonstrating finite-time perfect mixing with a finite energy constraint on the stirring flow. On the other hand, using a recent result by Wirosoetisno et al. ["Long time stability of a classical efficient scheme for two dimensional Navier-Stokes equations," SIAM J. Numer. Anal. 50(1), 126-150 (2012)], 10.1137/110834901 we establish that the H-1 mix-norm decays at most exponentially in time if the two-dimensional incompressible flow is constrained to have constant palenstrophy. Finite-time perfect mixing is thus ruled out when too much cost is incurred by small scale structures in the stirring. Direct numerical simulations in two dimensions suggest the impossibility of finite-time perfect mixing for flows with fixed power constraint and we conjecture an exponential lower bound on the H-1 mix-norm in this case. We also discuss some related problems from other areas of analysis that are similarly suggestive of an exponential lower bound for the H-1 mix-norm.
Gaining Insight into an Organization's Fixed Assets.
ERIC Educational Resources Information Center
Hardy, Elisabet
2003-01-01
Discusses issues related to school district implementation of June 2001 Government Accounting Standards Board (GASB) Statement 34 designed to change how schools report fixed assets. Includes planning for GASB implementation, conducting fixed-asset inventories, and making time for GASB reporting. (PKP)
Fixed-Response Questions with a Difference.
ERIC Educational Resources Information Center
Johnstone, Alex H.; Ambusaidi, Abdullah
2002-01-01
Offers three types of fixed-response questions that are designed to overcome drawbacks appearing in the conventional forms of fixed-response questions such as not allowing the examiner to investigate reasoning, background, or prevent guessing. (Contains 14 references.) (Author/YDS)
Inverse Scattering at Fixed Energy on Surfaces with Euclidean Ends
NASA Astrophysics Data System (ADS)
Guillarmou, Colin; Salo, Mikko; Tzou, Leo
2011-05-01
On a fixed Riemann surface ( M 0, g 0) with N Euclidean ends and genus g, we show that, under a topological condition, the scattering matrix S V ( λ) at frequency λ > 0 for the operator Δ+ V determines the potential V if {Vin C^{1,α}(M_0)\\cap e^{-γ d(\\cdot,z_0)^j}L^infty(M_0)} for all γ > 0 and for some {jin\\{1,2\\}} , where d( z, z 0) denotes the distance from z to a fixed point {z_0in M_0} . The topological condition is given by {N≥ max(2g+1,2)} for j = 1 and by N ≥ g + 1 if j = 2. In {mathbb {R}^2} this implies that the operator S V ( λ) determines any C 1, α potential V such that {V(z)=O(e^{-γ|z|^2})} for all γ > 0.
Evolutionary quantum cosmology in a gauge-fixed picture
Vakili, Babak
2011-05-15
We study the classical and quantum models of a flat Friedmann-Robertson-Walker space-time, coupled to a perfect fluid, in the context of the consensus and a gauge-fixed Lagrangian frameworks. It is shown that, either in the usual or in the gauge-fixed actions, the evolution of the Universe based on the classical cosmology represents a late time power law expansion, coming from a big-bang singularity in which the scale factor goes to zero for the standard matter, and tending towards a big-rip singularity in which the scale factor diverges for the phantom fluid. We then employ the familiar canonical quantization procedure in the given cosmological setting to find the cosmological wave functions in the corresponding minisuperspace. Using a gauge-fixed (reduced) Lagrangian, we show that it may lead to a Schroedinger equation for the quantum-mechanical description of the model under consideration, the eigenfunctions of which can be used to construct the time dependent wave function of the Universe. We use the resulting wave function in order to investigate the possibility of the avoidance of classical singularities due to quantum effects by means of the many-worlds and ontological interpretation of quantum cosmology.
47 CFR 80.477 - AMTS points of communication.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 47 Telecommunication 5 2010-10-01 2010-10-01 false AMTS points of communication. 80.477 Section 80... communication. (a) AMTS coast stations may communicate with fixed platform stations located in the offshore... frequencies on a secondary basis for fixed service communications to support offshore AMTS operations....
Sahara, N; Tomiyama, T; Mori, H
2000-05-01
Missense and splicing point mutations have been found in the tau gene in families with frontotemporal dementia with parkinsonism linked to chromosome 17 (FTDP-17). Of these mutations, we examined four exonic missense point mutations (G272V, P301L, V337M and R406W) in 3-repeat or 4-repeat tau isoform on the transfection experiment. The effects of two mutations (G272V or P301L) on microtubules were subtle whereas those of two other mutations (V337M or R406W) were dramatically significant when these two mutations were constructed into 3-repeat tau but not into 4-repeat tau. The R406W mutation induced an alternation of microtubules to form dotted or fragmented forms retaining colocalization of tau with tubulin whereas the V337M mutation predominantly disrupted microtubule networks and diminished colocalization of tau and tubulin. The effect of the mutations on microtubules were thus site-dependent and isoform-dependent. Tau with R406W mutation was found to be colocalized with tubulin without filamentous structures on confocal views, suggesting that the carboxyl region of tau played a different role from tubulin-binding domain on microtubule assemble. Another abnormal property was identified in tau with R406W mutation that failed to suffer phosphorylation. Thus, diverse effects of tau mutations on microtubules may explain the various clinicopathologies of FTDP-17 and related tauopathies. PMID:10797541
NASA Technical Reports Server (NTRS)
1975-01-01
The role played by individual citizens as consumers of energy was examined, with emphasis on studying ways in which their action could result in energy conservation. It was shown that there are ways that energy can be conserved in this way, with citizens acting either individually or in groups. The potential savings are significant, but the actual savings may be quite small. The citizens need to be motivated to save and to believe in a conservation ethic; developing such an ethic is difficult, and perhaps not responsive to the shotgun approach now being attempted. The true course of action may be to synthesize new societal structures that provide the maximum evolution of culture within the limitation of scarce energy resources.
McColl, Mary Ann; Aiken, Alice; Smith, Karen; McColl, Alexander; Green, Michael; Godwin, Marshall; Birtwhistle, Richard; Norman, Kathleen; Brankston, Gabrielle; Schaub, Michael
2015-01-01
Abstract Objective To present the results of a pilot study of an innovative methodology for translating best evidence about spinal cord injury (SCI) for family practice. Design Review of Canadian and international peer-reviewed literature to develop SCI Actionable Nuggets, and a mixed qualitative-quantitative evaluation to determine Nuggets’ effect on physician knowledge of and attitudes toward patients with SCI, as well as practice accessibility. Setting Ontario, Newfoundland, and Australia. Participants Forty-nine primary care physicians. Methods Twenty Actionable Nuggets (pertaining to key health issues associated with long-term SCI) were developed. Nugget postcards were mailed weekly for 20 weeks to participating physicians. Prior knowledge of SCI was self-rated by participants; they also completed an online posttest to assess the information they gained from the Nugget postcards. Participants’ opinions about practice accessibility and accommodations for patients with SCI, as well as the acceptability and usefulness of Nuggets, were assessed in interviews. Main findings With Actionable Nuggets, participants’ knowledge of the health needs of patients with SCI improved, as knowledge increased from a self-rating of fair (58%) to very good (75%) based on posttest quiz results. The mean overall score for accessibility and accommodations in physicians’ practices was 72%. Participants’ awareness of the need for screening and disease prevention among this population also increased. The usefulness and acceptability of SCI Nugget postcards were rated as excellent. Conclusion Actionable Nuggets are a knowledge translation tool designed to provide family physicians with concise, practical information about the most prevalent and pressing primary care needs of patients with SCI. This evidence-based resource has been shown to be an excellent fit with information consumption processes in primary care. They were updated and adapted for distribution by the Canadian Medical Association to approximately 50 000 primary care physicians in Canada, in both English and French. PMID:26167564
Photogrammetric Measurements in Fixed Wing Uav Imagery
NASA Astrophysics Data System (ADS)
Glch, E.
2012-07-01
Several flights have been undertaken with PAMS (Photogrammetric Aerial Mapping System) by Germap, Germany, which is briefly introduced. This system is based on the SmartPlane fixed-wing UAV and a CANON IXUS camera system. The plane is equipped with GPS and has an infrared sensor system to estimate attitude values. A software has been developed to link the PAMS output to a standard photogrammetric processing chain built on Trimble INPHO. The linking of the image files and image IDs and the handling of different cases with partly corrupted output have to be solved to generate an INPHO project file. Based on this project file the software packages MATCH-AT, MATCH-T DSM, OrthoMaster and OrthoVista for digital aerial triangulation, DTM/DSM generation and finally digital orthomosaik generation are applied. The focus has been on investigations on how to adapt the "usual" parameters for the digital aerial triangulation and other software to the UAV flight conditions, which are showing high overlaps, large kappa angles and a certain image blur in case of turbulences. It was found, that the selected parameter setup shows a quite stable behaviour and can be applied to other flights. A comparison is made to results from other open source multi-ray matching software to handle the issue of the described flight conditions. Flights over the same area at different times have been compared to each other. The major objective was here to see, on how far differences occur relative to each other, without having access to ground control data, which would have a potential for applications with low requirements on the absolute accuracy. The results show, that there are influences of weather and illumination visible. The "unusual" flight pattern, which shows big time differences for neighbouring strips has an influence on the AT and DTM/DSM generation. The results obtained so far do indicate problems in the stability of the camera calibration. This clearly requests a usage of GCPs for all projects, independent on the application. The effort is estimated to be even higher as expected, as also self-calibration will be an issue to handle a possibly instable camera calibration. To overcome some of the encountered problems with the very specific features of UAV flights a software UAVision was developed based on Open Source libraries to produce input data for bundle adjustment of UAV images by PAMS. The empirical test results show a considerable improvement in the matching of tie points. The results do, however, show that the Open Source bundle adjustment was not applicable to this type of imagery. This still leaves the possibility to use the improved tie point correspondences in the commercial AT package.
Werner, Ralf; Holterhus, Paul-Martin
2014-01-01
Androgens are important for male sex development and physiology. Their actions are mediated by the androgen receptor (AR), a ligand-dependent nuclear transcription factor. The activity of the AR is controlled at multiple stages due to ligand binding and induced structural changes assisted by the foldosome, compartmentalization, recruitment of coregulators, posttranslational modifications and chromatin remodeling, leading to subsequent transcription of androgen-responsive target genes. Beside these short-term androgen actions, there is phenomenological and experimental evidence of long-term androgen programming in mammals and in the human during sensitive programming time windows, both pre- and postnatally. At the molecular level, research into androgen insensitivity syndrome has unmasked androgen programming at the transcriptome level, in genital fibroblasts and peripheral blood mononuclear cells, and at the epigenome level. Androgens are crucial for male sex development and physiology during embryogenesis, at puberty and in adult life. Testosterone and its more potent metabolite, dihydrotestosterone, which is converted from testosterone within the target cell by 5α-reductase II, are the main androgens involved in male sex differentiation. Androgen action is mediated by a single AR. The AR belongs to the nuclear receptor 3 group C, composed of the glucocorticoid receptor (NR3C1), mineralocorticoid receptor (NR3C2), progesterone receptor (NR3C3) and AR (NR3C4), and acts as a ligand-dependent transcription factor. PMID:25247642
46 CFR 535.801 - Independent action.
Code of Federal Regulations, 2012 CFR
2012-10-01
... fixed or maximum period of notice to the conference. A conference agreement shall not require or permit.... Furthermore, no term other than “adopt” (e.g., “follow,” “match”) can be used to describe the action...
46 CFR 535.801 - Independent action.
Code of Federal Regulations, 2013 CFR
2013-10-01
... fixed or maximum period of notice to the conference. A conference agreement shall not require or permit.... Furthermore, no term other than “adopt” (e.g., “follow,” “match”) can be used to describe the action...
46 CFR 535.801 - Independent action.
Code of Federal Regulations, 2014 CFR
2014-10-01
... fixed or maximum period of notice to the conference. A conference agreement shall not require or permit.... Furthermore, no term other than “adopt” (e.g., “follow,” “match”) can be used to describe the action...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-12-14
..., in FR Doc. 2011- 31762, on page 77296, in the thirty-second line of the third column, correct the... COMMISSION Self-Regulatory Organizations; Fixed Income Clearing Corporation; Notice of Filing of Proposed... Central Counterparty Services; Correction AGENCY: Securities and Exchange Commission. ACTION:...
43 CFR 3000.12 - What is the fee schedule for fixed fees?
Code of Federal Regulations, 2012 CFR
2012-10-01
... and the one-time location fee required by statute. 43 CFR part 3833. (b) The amount of a fixed fee is... Processing and Filing Fee Table Document/action FY 2013 fee Oil & Gas (parts 3100, 3110, 3120, 3130, 3150... 320 Lease or lease interest transfer 65 Leasing of Solid Minerals Other Than Coal and Oil Shale...
43 CFR 3000.12 - What is the fee schedule for fixed fees?
Code of Federal Regulations, 2014 CFR
2014-10-01
... statute. 43 CFR part 3833. (b) The amount of a fixed fee is not subject to appeal to the Interior Board of... Processing and Filing Fee Table Document/Action FY 2015 Fee Oil & Gas (parts 3100, 3110, 3120, 3130, 3150... Coal and Oil Shale (parts 3500, 3580) Applications other than those listed below 35. Prospecting...
ON LYAPUNOV FAMILIES AROUND COLLINEAR LIBRATION POINTS
Hou, X. Y.; Liu, L.
2009-06-15
Evolution details of the planar and vertical Lyapunov families around the three collinear libration points in the restricted three-body problem were studied. Researches before were generally restricted to be within the colliding orbits with the primaries and for fixed mass parameters {mu}. In this paper, members after colliding orbits were computed. With increasing {mu}, how these families evolve was studied.
Updraft Fixed Bed Gasification Aspen Plus Model
Energy Science and Technology Software Center (ESTSC)
2007-09-27
The updraft fixed bed gasification model provides predictive modeling capabilities for updraft fixed bed gasifiers, when devolatilization data is available. The fixed bed model is constructed using Aspen Plus, process modeling software, coupled with a FORTRAN user kinetic subroutine. Current updraft gasification models created in Aspen Plus have limited predictive capabilities and must be "tuned" to reflect a generalized gas composition as specified in literature or by the gasifier manufacturer. This limits the applicability ofmore » the process model.« less
The 1994 Fermilab Fixed Target Program
Conrad, J. |
1994-11-01
This paper highlights the results of the Fermilab Fixed Target Program that were announced between October, 1993 and October, 1994. These results are drawn from 18 experiments that took data in the 1985, 1987 and 1990/91 fixed target running periods. For this discussion, the Fermilab Fixed Target Program is divided into 5 major topics: hadron structure, precision electroweak measurements, heavy quark production, polarization and magnetic moments, and searches for new phenomena. However, it should be noted that most experiments span several subtopics. Also, measurements within each subtopic often affect the results in other subtopics. For example, parton distributions from hadron structure measurements are used in the studies of heavy quark production.
[FIXED COMBINATION ATORVASTATIN-EZETIMIBE (ATOZET®)].
Scheen, A J
2016-01-01
Cardiovascular prevention in subjects at high or very high risk requires a drastic reduction in LDL cholesterol according to the concept "the lower, the better". The combination of an inhibitor of cholesterol synthesis and a selective inhibitor of intestinal absorption results in a complementary and synergistic LDL-lowering activity. Besides a first fixed combination ezetimibe-simvastatin (Inegy®), a new fixed combination is presented, Atozet® that combines atorvastatin and ezetimibe. Because atorvastatin is more potent than simvastatin, this novel fixed combination should facilitate reaching therapeutic goals in terms of LDL cholesterol amongst patients with severe hypercholesterolaemia and/or at high or very high cardiovascular risk. PMID:26983314
Fixed target issues for the Tevatron Upgrade
Stefanski, R.
1988-08-29
The Tevatron Upgrade poses some interesting prospects for the Fixed-Target program if an option to extract the high energy proton beam is preserved. This paper presents a summary of the advantages of increased energy for fixed target experiments, and evaluates some of the more challenging technical issues. In particular, Bottom production, muon and neutrino interactions, and polarized /bar p/ experiments would benefit substantially from a higher energy primary beam. The new Main Injector will also be important for fixed target experiments as a source for test beams and intense kaon and neutrino beams. 4 refs., 2 tabs.
EVALUATING MULTICOMPONENT COMPETITIVE ADSORPTION IN FIXED BEDS
An equilibrium column model (ECM) was developed to evaluate multicomponent competition in fixed-bed adsorption columns. The model ignores mass transfer resistances and uses ideal adsorbed solution theory to predict the competitive effects in multicomponent mixtures. The bed capac...
Action Learning: Avoiding Conflict or Enabling Action
ERIC Educational Resources Information Center
Corley, Aileen; Thorne, Ann
2006-01-01
Action learning is based on the premise that action and learning are inextricably entwined and it is this potential, to enable action, which has contributed to the growth of action learning within education and management development programmes. However has this growth in action learning lead to an evolution or a dilution of Revan's classical…
Planar Biconnectivity Augmentation with Fixed Embedding
NASA Astrophysics Data System (ADS)
Gutwenger, Carsten; Mutzel, Petra; Zey, Bernd
A combinatorial embedding {Pi} of a planar graph G = (V,E) is defined by the cyclic order of incident edges around each vertex in a planar drawing of G. The planar biconnectivity augmentation problem with fixed embedding (PBA-Fix) asks for a minimum edge set E' ⊆ V×V that augments {Pi} to a combinatorial embedding {Pi}' of G + E' such that G + E' is biconnected and {Pi} is preserved, i.e., {Pi}' restricted to G yields again {Pi}.
Fixed-target physics at Fermilab
Bjorken, J.D.
1985-03-01
The Fermilab Energy Saver is now successfully commissioned and fixed-target experimentation at high energy (800 GeV) has begun. In addition, a number of new experiments designed to exploit the unique features of the Tevatron are yet to come on-line. In this talk, we will review recent accomplishments in the fixed-target program and describe experiments in progress and others yet to come.
ERIC Educational Resources Information Center
Glover, Ashley C.; Roane, Henry S.; Kadey, Heather J.; Grow, Laura L.
2008-01-01
Progressive-ratio (PR) schedules were used to identify the break point (i.e., the last schedule value completed) for 2 reinforcers under single and concurrent schedules. After the respective break points were established, the same reinforcers were presented under concurrent fixed-ratio (FR) schedules that were yoked to the break points obtained…
Experiences with Light Weight Fixed Wing Aerial Mapping UAVs
NASA Astrophysics Data System (ADS)
Mayr, W.
2014-11-01
UAVs seem to be the next "cloud" like topic, not only in geomatics. Unmanned Airborne Vehicles are not a wonder-tool, but a complementary approach to resolve some tasks more efficiently than before or at all. Since 2006 we commercially apply fixed wing, light weight UAVs for aerial mapping purposes. In this paper we like to share our experiences with UAVs of less than 5 kg and illuminate some limitations as well as potentials. Whereas multicopters seem to be in use everywhere, fixed wing UAVs more frequently seem to be applied in specific and geospatially oriented applications. Having processed several hundred UAV aerial mapping projects there forms a stable picture of this technology. Our impressions on durability, handling, and reliability of fixed wing UAVs get presented. We report on our day-to-day experiences and point to often simple hurdles to overcome. Various cameras were flown, different approaches of handling their geometries with different software packages were undertaken. Remarks to achieved geometric accuracies as well as the consequences of using dual frequency GPS instead of simple yet great single frequency GPS are discussed. All of this packed into the subsequent paper.
Applications of fixed-time flow cytometry in cell biology
NASA Astrophysics Data System (ADS)
Tarnok, Attila
1998-04-01
Flow cytometric (FCM) measurement of intracellular free calcium [Ca2+]i, transients is usually done by two methods: (a) after a short prerun period to assess the baseline the measurement is stopped, stimulus is added and the measurement continued or (b) stimulus is injected during measurement and the sample pressure briefly increased to deliver cells rapidly to the detection point. In (a) measurement of very short transients [Ca2+]i is impeded by the lag time between stimulus addition and restart of acquisition. In (b) response of pressure sensitive cells is hard to analyze. Furthermore, (a) and (b) do not allow to quantify and sort rare responders. A simple Fixed- Time device has been developed. Ca2+ sensitive fluorescent dye labeled cells and a stimulus are placed in different vials. Both fluids are forced by the same pressure through tubing that merges into a T-junction where they mix and are delivered through a connecting tube to the FCM: [Ca2+]i is measured at a certain time after stimulation that is adjusted by sample flow rate and length of the connecting tube. With Fixed-Time, the pressure sensitive neuronal NH15-CA2 cell was analyzed. Furthermore, rare neurotransmitter responsive fibroblast from normal and transfected cultures were sorted and cloned and their dose response characterized. The results demonstrate that fixed- time FCM is an important tool for the analysis of the cells physiology and the preparation of responders.
The Fixed Irreducible Bridge Ensemble for Self-Avoiding Walks
NASA Astrophysics Data System (ADS)
Gilbert, Michael James
2015-04-01
We define a new ensemble for self-avoiding walks in the upper half-plane, the fixed irredicible bridge ensemble, by considering self-avoiding walks in the upper half-plane up to their -th bridge height, , and scaling the walk by to obtain a curve in the unit strip, and then taking . We then conjecture a relationship between this ensemble to in the unit strip from 0 to a fixed point along the upper boundary of the strip, integrated over the conjectured exit density of self-avoiding walk spanning a strip in the scaling limit. We conjecture that there exists a positive constant such that converges in distribution to that of a stable random variable as . Then the conjectured relationship between the fixed irreducible bridge scaling limit and can be described as follows: If one takes a SAW considered up to and scales by and then weights the walk by to an appropriate power, then in the limit , one should obtain a curve from the scaling limit of the self-avoiding walk spanning the unit strip. In addition to a heuristic derivation, we provide numerical evidence to support the conjecture and give estimates for the boundary scaling exponent.
Event Display for the Fixed Target Experiment BM@N
NASA Astrophysics Data System (ADS)
Gertsenberger, Konstantin
2016-02-01
One of the main problems to be solved in modern high energy physics experiments on particle collisions with a fixed target is the visual representation of the events during the experiment run. The article briefly describes the structure of the BM@N facility at the Nuclotron being under construction at the Joint Institute for Nuclear Research with the aim to study properties of the baryonic matter in collisions of ions with fixed target at energies up to 4 GeV/nucleon (for Au79+). Aspects concerning the visualization of data and detector details at the modern experiments and possibilities of practical applications are discussed. We present event display system intended to visualize the detector geometries and events of particle collisions with the fixed target, its options and features as well as integration with BMNRoot software. The examples of graphical representation of simulated and reconstructed points and particle tracks with BM@N geometry are given for central collisions of Au79+ ions with gold target and deuterons with carbon target.
NASA Astrophysics Data System (ADS)
Frank, T. D.
A Lotka-Volterra model for an arbitrary number of competitors is studied for different ratios of self-inhibition versus cross-inhibition. It is shown that winner-takes-all fixed points (states of single surviving species) are the only stable fixed points of the model when cross-inhibition exceeds self-inhibition. Secondary bifurcations in terms of bifurcations between winner-takes-all fixed points induced by changes in the exponential growth rates of competitors are studied and the critical control parameters are identified. A selection principle is derived that states that evolution proceeds in such a way that exponential growth rates of surviving competitors are magnified in evolutionary bifurcation steps. The interacting competitor model is applied as an amplitude equation model for interacting patterns of self-organizing pattern formation systems with an eye on action selection and compulsive behaviors in humans. The possibility is discussed that human behavior is subjected to the selection principle of "faster growth rates".
Continuous, fixed-ratio, and fixed-interval reinforcement in honey bees
Grossmann, Klaus E.
1973-01-01
Bees learned to enter a Plexiglas tube and to suck small portions of sugar solution; every entry or every fifth entry was reinforced. During an extinction phase, the bees on the fixed-ratio schedule emitted twice as many responses as did those given continuous reinforcement. Bees on a fixed-interval schedule of reinforcement emitted lower response rates than did those given fixed-ratio reinforcement. By extending the conditioning procedure for several days, it was possible to maintain responding with fixed-ratio schedules requiring 30 responses per reinforcement and with fixed-interval values up to 90 sec. Under fixed-interval schedules, response rates did not increase toward the end of the reinforcement intervals. PMID:16811686
Optical simulation for a fixed spherical solar collector.
Authier, B; Hill, L; Duban, M; Trarieux, P; Sarazin, M; Nadeau, P
1979-09-15
To calculate the absorber dimensions for a fixed spherical solar collector, an optical simulation of the raytracing type is proposed. The physical quantities, which have an effect upon these dimensions, are described as well as the measurement methods. Once the dimensions are determined, the incident flux on the absorber surface can be calculated by the same program in terms of different zenith distances. These calculations can be checked by comparing the calculated flux on the surface of the absorber with the measured flux at different points along the absorber aimed at the full moon instead of at the sun. Through the data obtained from the measurements, fluctuating points of high flux and permanent zones which receive double and triple reflection rays have been studied. PMID:20212809
A comparison of carbide fracture during fixed depth and fixed load scratch tests
Prasad, S.V.; Kosel, T.H.
1985-01-01
In order to simulate abrasion of dual-phase materials containing large carbides under fixed depth conditions an apparatus has been designed and used to perform scratch tests at a fixed depth of cut on such materials. The scratch test consists of two support arms tipped with small steel balls held in contact with surface by /sup 700/ g, while the scratch tool is mounted on the tip of a central arm whose adjustable length allow control of the depth of cut. The scratch tool does not deflect significant when it encounters a large carbide. Scratch tests with the new apparatus have been performed on Co-base Stellite alloys containing large Cr-rich carbides, using individual particles of alumina as scratch tools to generate fixed depth scratches. A in situ SEM scratch test apparatus has also been used to genrate fixed load scratches. Comparison of the scratches shows that for comparable average scratch depths, under fixed load conditions the scratch tool deflects over the carbides without causing fracture, but that since it cannot deflect under fixed depth conditions it induces gross carbide fracture. Results suggest that the fixed depth scratch test can be successfully employed to simulate fixed depth abrasion, which has been previously shown to generate gross carbide fracture in these alloys. The in situ SEM scratch test simulates fixed load abrasion conditions such as those which occur in rubber wheel abrasion tests. 12 refs., 9 figs
Inadvertent tooth movement with fixed lingual retainers.
Shaughnessy, Timothy G; Proffit, William R; Samara, Said A
2016-02-01
Fixed retainers are effective in maintaining the alignment of the anterior teeth more than 90% of the time, but they can produce inadvertent tooth movement that in the most severe instances requires orthodontic retreatment managed with a periodontist. This is different from relapse into crowding when a fixed retainer is lost. These problems arise when the retainer breaks but remains bonded to some or all teeth, or when an intact retainer is distorted by function or was not passive when bonded. In both instances, torque of the affected teeth is the predominant outcome. A fixed retainer made with dead soft wire is the least likely to create torque problems but is the most likely to break. Highly flexible twist wires bonded to all the teeth appear to be the most likely to produce inadvertent tooth movement, but this also can occur with stiffer wires bonded only to the canines. Orthodontists, general dentists, and patients should be aware of possible problems with fixed retainers, especially those with all teeth bonded, because the patient might not notice partial debonding. Regular observations of patients wearing fixed retainers by orthodontists in the short term and family dentists in the long term are needed. PMID:26827985
The gravitational Hamiltonian, first order action, Poincaré charges and surface terms
NASA Astrophysics Data System (ADS)
Corichi, Alejandro; Reyes, Juan D.
2015-10-01
We consider the issue of attaining a consistent Hamiltonian formulation, after a 3+1 splitting, of a well-defined action principle for asymptotically flat gravity. More precisely, our starting point is the gravitational first order Holst action with surface terms and fall off conditions that make the variational principle and the covariant phase space formulation well-defined for asymptotically flat spacetimes. Keeping all surface terms and paying due attention to subtleties that arise from the different cut-offs at infinity, we give a derivation of the gravitational Hamiltonian starting from this action. The 3+1 decomposition and time gauge fixing results in a well-defined Hamiltonian action and a well-defined Hamiltonian formulation for the standard—and more general—asymptotic ADM conditions. Unlike the case of the Einstein-Hilbert action with Gibbons-Hawking-York or Hawking-Horowitz terms, here we do recover the ADM energy momentum from the covariant surface term also when more general variations respecting asymptotic flatness are allowed. Additionally, our strategy yields a derivation of the parity conditions for connection variables independent of the conditions given by Regge and Teitelboim for ADM variables. Finally, we exhibit the other Poincaré generators in terms of real Ashtekar-Barbero variables. We complement previous constructions in self-dual variables by pointing out several subtleties and refining the argument showing that—on shell—they coincide with the ADM charges. Our results represent the first consistent treatment of the Hamiltonian formulation for the connection-tetrad gravitational degrees of freedom, starting from a well posed action, in the case of asymptotically flat boundary conditions.
Paerl, Hans W.; Xu, Hai; Hall, Nathan S.; Zhu, Guangwei; Qin, Boqiang; Wu, Yali; Rossignol, Karen L.; Dong, Linghan; McCarthy, Mark J.; Joyner, Alan R.
2014-01-01
Excessive anthropogenic nitrogen (N) and phosphorus (P) inputs have caused an alarming increase in harmful cyanobacterial blooms, threatening sustainability of lakes and reservoirs worldwide. Hypertrophic Lake Taihu, China’s third largest freshwater lake, typifies this predicament, with toxic blooms of the non-N2 fixing cyanobacteria Microcystis spp. dominating from spring through fall. Previous studies indicate N and P reductions are needed to reduce bloom magnitude and duration. However, N reductions may encourage replacement of non-N2 fixing with N2 fixing cyanobacteria. This potentially counterproductive scenario was evaluated using replicate, large (1000 L), in-lake mesocosms during summer bloom periods. N+P additions led to maximum phytoplankton production. Phosphorus enrichment, which promoted N limitation, resulted in increases in N2 fixing taxa (Anabaena spp.), but it did not lead to significant replacement of non-N2 fixing with N2 fixing cyanobacteria, and N2 fixation rates remained ecologically insignificant. Furthermore, P enrichment failed to increase phytoplankton production relative to controls, indicating that N was the most limiting nutrient throughout this period. We propose that Microcystis spp. and other non-N2 fixing genera can maintain dominance in this shallow, highly turbid, nutrient-enriched lake by outcompeting N2 fixing taxa for existing sources of N and P stored and cycled in the lake. To bring Taihu and other hypertrophic systems below the bloom threshold, both N and P reductions will be needed until the legacy of high N and P loading and sediment nutrient storage in these systems is depleted. At that point, a more exclusive focus on P reductions may be feasible. PMID:25405474
Doya, Kenji
2015-01-01
The striatum is a major input site of the basal ganglia, which play an essential role in decision making. Previous studies have suggested that subareas of the striatum have distinct roles: the dorsolateral striatum (DLS) functions in habitual action, the dorsomedial striatum (DMS) in goal-directed actions, and the ventral striatum (VS) in motivation. To elucidate distinctive functions of subregions of the striatum in decision making, we systematically investigated information represented by phasically active neurons in DLS, DMS, and VS. Rats performed two types of choice tasks: fixed- and free-choice tasks. In both tasks, rats were required to perform nose poking to either the left or right hole after cue-tone presentation. A food pellet was delivered probabilistically depending on the presented cue and the selected action. The reward probability was fixed in fixed-choice task and varied in a block-wise manner in free-choice task. We found the following: (1) when rats began the tasks, a majority of VS neurons increased their firing rates and information regarding task type and state value was most strongly represented in VS; (2) during action selection, information of action and action values was most strongly represented in DMS; (3) action-command information (action representation before action selection) was stronger in the fixed-choice task than in the free-choice task in both DLS and DMS; and (4) action-command information was strongest in DLS, particularly when the same choice was repeated. We propose a hypothesis of hierarchical reinforcement learning in the basal ganglia to coherently explain these results. PMID:25716849
Radiative convection with a fixed heat flux
NASA Astrophysics Data System (ADS)
Aumaı̂tre, S.
2001-10-01
We have determined the marginal stability curve of convective instability in the usual Rayleigh-Bénard configuration with radiative transfer and a fixed total heat flux at the boundaries instead of a fixed temperature. In the Milne-Eddington approximation, radiative transfer introduces a new length scale and breaks the invariance of the Boussinesq equations under an arbitrary temperature shift, which occurs when the heat flux is fixed at the boundaries. The convergence to the limits where the non-radiative cases are expected is studied in this approximation. Then, using a second-order perturbative calculation, we show that the presence of radiation can change qualitatively the instability pattern: there is a range of optical parameters where the Cahn-Hillard equation is not anymore the one appropriate to describe the instability near the threshold.
Constructing optimal backbone segments for joining fixed DNA base pairs.
Mazur, J; Jernigan, R L; Sarai, A
1996-01-01
A method is presented to link a sequence of space-fixed base pairs by the sugar-phosphate segments of single nucleotides and to evaluate the effects in the backbone caused by this positioning of the bases. The entire computational unit comprises several nucleotides that are energy-minimized, subject to constraints imposed by the sugar-phosphate backbone segments being anchored to space-fixed base pairs. The minimization schemes are based on two stages, a conjugate gradient method followed by a Newton-Raphson algorithm. Because our purpose is to examine the response, or relaxation, of an artificially stressed backbone, it is essential to be able to obtain, as closely as possible, a lowest minimum energy conformation of the backbone segment in conformational space. For this purpose, an algorithm is developed that leads to the generation of an assembly of many local energy minima. From these sets of local minima, one conformation corresponding to the one with the lowest minimum is then selected and designated to represent the backbone segment at its minimum. The effective electrostatic potential of mean force is expressed in terms of adjustable parameters that incorporate solvent screening action in the Coulombic interactions between charged backbone atoms; these parameters are adjusted to obtain the best fit of the nearest-neighbor phosphorous atoms in an x-ray structure. PMID:8874023
a Fixed-Mesh Method for General Moving Objects in Fluid Flow
NASA Astrophysics Data System (ADS)
Wei, Gengsheng
In this work, a fixed-mesh method for general moving objects in fluid flow was developed and implemented into the commercial CFD software FLOW-3D. A general moving object is a rigid body with any type of six-degrees-of-freedom, fixed-point and fixed-axis motion which can be either user-prescribed or dynamically coupled with fluid flow. The method allows multiple general moving objects, and each of them can possess any different type of motion. Area and volume fractions to represent the objects in the fixed-grid are calculated at every time step to describe time-variation of object locations and orientations. Continuity and momentum equations for fluid are modified to account for the effects of object motion on fluid flow. A good agreement is achieved between computational and experimental results in an application to a valve problem.
A fixed Fresnel lens with tracking collector
NASA Astrophysics Data System (ADS)
Kritchman, E. M.; Friesem, A. A.; Yekutieli, G.
1981-01-01
The application of a wide angle concentrating Fresnel lens to a linear solar energy system, in which the optical concentration is stationary while the absorber follows the locus of best foci, is investigated. The two substantial direction possibilities of the linear axis, east-west and polar, are compared to each other. It is shown that such a concentrator may operate about six hours a day throughout the year with an average effective concentration exceeding 10. Specifically, a polar installation, including a fixed lens and a fixed assembly of separate absorbers behind it, may enable sufficient concentration for residential heating and airconditioning without any moving parts
Reflections on Working with Virtual Action Learning
ERIC Educational Resources Information Center
Pedler, Mike; Hauser, Bernhard; Caulat, Ghislaine
2014-01-01
This paper brings together the reflections of the authors on their shared and individual experiences of virtual action learning. Whilst many conclusions are shared, there are also some points of difference in practices.
Vibration suppression of fixed-time jib crane maneuvers
Parker, G.G.; Petterson, B.; Dohrmann, C.R.; Robinett, R.D.
1995-02-01
A jib crane consists of a pendulum-like end line attached to a rotatable jib. Within this general category of cranes there exist devices with multiple degrees of freedom including variable load-line length and variable jib length. These cranes are commonly used for construction and transportation applications. Point-to-point payload maneuvers using jib cranes are performed so as not to excite the spherical pendulum modes of their cable and payload assemblies. Typically, these pendulum modes, although time-varying, exhibit low frequencies. The resulting maneuvers are therefore performed slowly, contributing to high construction and transportation costs. The crane considered here consists of a spherical pendulum attached to a rigid jib. The other end of the jib is attached to a direct drive motor for generating rotational motion. A general approach is presented for determining the open-loop trajectories for the jib rotation for accomplishing fixed-time, point-to-point, residual oscillation free, symmetric maneuvers. These residual oscillation free trajectories purposely excite the pendulum modes in such a way that at the end of the maneuver the oscillatory degrees of freedom are quiescent. Simulation results are presented with experimental verification.
Quick-Release Pin With Lever Action
NASA Technical Reports Server (NTRS)
Trevino, Robert C.
1995-01-01
Lever-action quick-release pin operated more easily. Mechanism operated with gloved hand. In modified version, lever added to handle to facilitate actuation. Lever action reduces actuation force. Lever-action pin operated by squeezing on any point of moveable ends of lever and handle together between thumb and forefinger or by simply grasping and squeezing handle and lever with entire hand in more natural grasp.
Physics landscape-fixed target energies
Berger, E.L.
1989-10-01
An introductory review is presented of physics issues and opportunities at Fermilab fixed-target energies. Included are discussions of precision electroweak studies; deep inelastic lepton scattering; heavy quark production, spectroscopy, and decays; perturbative QCD; prompt photon production; massive lepton production; and spin dependence. 79 refs., 7 figs.
Management strategy 3: fixed rate fertilizer applications
Technology Transfer Automated Retrieval System (TEKTRAN)
Previous chapters outlined management strategies for pond fertilization that take into account specific individual pond nutrient needs. Those methods would most likely be more ecologically efficient than a pre-determined fixed-rate nutrient addition strategy. However, the vast majority of available ...
Microanalysis of fixed-interval responding
Gentry, G.D.; Weiss, B.; Laties, V.G.
1983-03-01
The fixed-interval schedule of reinforcement is one of the more widely studied schedules in the experimental analysis of behavior and is also a common baseline for behavior pharmacology. Despite many intensive studies, the controlling variables and the pattern of behavior engendered are not well understood. The present study examined the microstructure and superstructure of the behavior engendered by a fixed-interval 5- and a fixed-interval 15-minute schedule of food reinforcement in the pigeon. Analysis of performance typical of fixed-interval responding indicated that the scalloped pattern does not result from smooth acceleration in responding, but, rather, from renewed pausing early in the interval. Individual interresponse-time (IRT) analyses provided no evidence of acceleration. There was a strong indication of alternation is shorter-longer IRTs, but these shorter-longer IRTs did not occur at random, reflecting instead a sequential dependency in successive IRTs. Furthermore, early in the interval there was a high relative frequency of short IRTs. Such a pattern of early pauses and short IRTs does not suggest behavior typical of reinforced responding as exemplified by the pattern found near the end of the interval. Thus, behavior from clearly scalloped performance can be classified into three states: postreinforcement pause, interim behavior, and terminal behavior. 31 references, 11 figures, 4 tables.
29 CFR 1917.118 - Fixed ladders.
Code of Federal Regulations, 2013 CFR
2013-07-01
... of equipment. (3) Ladder safety device means a support system limiting an employee's drop or fall... installed for guidance through the opening. (6) The side rails of ladders shall extend at least 36 inches (0...) MARINE TERMINALS Terminal Facilities § 1917.118 Fixed ladders. (a) Scope and applicability. This...
29 CFR 1917.118 - Fixed ladders.
Code of Federal Regulations, 2014 CFR
2014-07-01
... of equipment. (3) Ladder safety device means a support system limiting an employee's drop or fall... installed for guidance through the opening. (6) The side rails of ladders shall extend at least 36 inches (0...) MARINE TERMINALS Terminal Facilities § 1917.118 Fixed ladders. (a) Scope and applicability. This...
29 CFR 1917.118 - Fixed ladders.
Code of Federal Regulations, 2011 CFR
2011-07-01
... of equipment. (3) Ladder safety device means a support system limiting an employee's drop or fall... installed for guidance through the opening. (6) The side rails of ladders shall extend at least 36 inches (0...) MARINE TERMINALS Terminal Facilities § 1917.118 Fixed ladders. (a) Scope and applicability. This...
29 CFR 1917.118 - Fixed ladders.
Code of Federal Regulations, 2012 CFR
2012-07-01
... of equipment. (3) Ladder safety device means a support system limiting an employee's drop or fall... installed for guidance through the opening. (6) The side rails of ladders shall extend at least 36 inches (0...) MARINE TERMINALS Terminal Facilities § 1917.118 Fixed ladders. (a) Scope and applicability. This...
29 CFR 1917.120 - Fixed stairways.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 29 Labor 7 2014-07-01 2014-07-01 false Fixed stairways. 1917.120 Section 1917.120 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR.... Where doors or gates open on a stairway, a landing platform shall be provided. Door swing shall...
29 CFR 1917.120 - Fixed stairways.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 29 Labor 7 2011-07-01 2011-07-01 false Fixed stairways. 1917.120 Section 1917.120 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR.... Where doors or gates open on a stairway, a landing platform shall be provided. Door swing shall...
29 CFR 1917.120 - Fixed stairways.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 29 Labor 7 2013-07-01 2013-07-01 false Fixed stairways. 1917.120 Section 1917.120 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR.... Where doors or gates open on a stairway, a landing platform shall be provided. Door swing shall...
Stress tolerant crops from nitrogen fixing trees
Becker, R.; Saunders, R.M.
1983-01-01
Notes are given on the nutritional quality and uses of: pods of Geoffroea decorticans, a species tolerant of saline and limed soils and saline water; seeds of Olneya tesota which nodulates readily and fixes nitrogen and photosynthesizes at low water potential; and pods of Prosopis chilensis and P. tamarugo which tolerate long periods without rain. 3 references.
Florida Educational Fixed Capital Outlay Budgeting.
ERIC Educational Resources Information Center
King, Candice A.; Carpenter, James L.
In July 1979, the Florida legislature commissioned a comprehensive evaluation of the state's educational fixed capital outlay (EFCO) program, through which the state funded all capital projects at all levels of public education. The study, completed for the 1980 legislative session, comprised 18 topical reports including EFCO funding recipients,…
Fixing Advising: A Model for Faculty Advising
ERIC Educational Resources Information Center
Crocker, Robert M.; Kahla, Marlene; Allen, Charlotte
2014-01-01
This paper addresses mandates to fix the advising process with a focus on faculty advising systems. Measures of student success and satisfaction, administrative issues, and faculty concerns are among the many factors discussed. Regression analysis is used to explore long-voiced faculty complaints that students do not follow advice. A case study is…
Fixing the Shadows While Moving the Gnomon
ERIC Educational Resources Information Center
Gangui, Alejandro
2015-01-01
It is a common practice to fix a vertical gnomon and study the moving shadow cast by it. This shows our local solar time and gives us a hint regarding the season in which we perform the observation. The moving shadow can also tell us our latitude with high precision. In this paper we propose to exchange the roles and while keeping the shadows…
29 CFR 1910.27 - Fixed ladders.
Code of Federal Regulations, 2013 CFR
2013-07-01
...). For fixed ladders consisting of wood side rails and wood rungs or cleats, used at a pitch in the range... ladder shall be 36 inches for a pitch of 76 degrees, and 30 inches for a pitch of 90 degrees (fig. D-2 of this section), with minimum clearances for intermediate pitches varying between these two limits...
Force dynamics in fixed-ratio schedules.
Pinkston, Jonathan W; McBee, Lindsey N
2014-03-01
Fixed-ratio schedules are widely used in behavioral research. Although fixed-ratio schedules often conjure up relationships to work and effort, little is known about effort-related measures in these schedules. Early research had shown that force and effort of operant behavior vary systematically during the execution of ratio schedules, and the goal of the present study was to revisit early research on force dynamics in fixed-ratio schedules. Four rats earned sucrose by pressing an isometric force transducer. Presses produced sucrose after ten or twenty responses. In general, the force of responses increased then decreased systematically across the ratio. The possibility that decreases in force during ratio execution was due to a trade-off with the differential reinforcement of short inter-response times (IRT) was investigated in an additional condition where sucrose was made available according to a tandem fixed-ratio 19 inter-response (IRT)> t schedule. The tandem IRT requirement did not eliminate decreasing trends in force across the ratio; unexpectedly, the tandem requirement did eliminate increases in force early in the ratio, which may reflect sequence-level organization operating in the control of force dynamics. PMID:24315798
Fixing the Shadows While Moving the Gnomon
ERIC Educational Resources Information Center
Gangui, Alejandro
2015-01-01
It is a common practice to fix a vertical gnomon and study the moving shadow cast by it. This shows our local solar time and gives us a hint regarding the season in which we perform the observation. The moving shadow can also tell us our latitude with high precision. In this paper we propose to exchange the roles and while keeping the shadows
"If the Water Is Nasty, Fix It."
ERIC Educational Resources Information Center
Boston, Bruce O.
1999-01-01
After taking an environmental inventory of their community, seventh-graders in a Denver-area middle school decided to tackle the drinking water problem and fix it. The school is one of seven participating in Earth Force, an environmental and community-service-learning program based in Alexandria, Virginia. The program's progress and six-step…
Affirmative Action Is an International Issue
ERIC Educational Resources Information Center
Pipes, Randolph B.
2007-01-01
This article contains comments on the article by Vasquez and Jones (see record 2006-01690-003), which focuses on diversity and begins with a discussion of affirmative action. The current author discusses his own three related points: first, it is virtually impossible, in our current culture, to agree on what constitutes affirmative action and…
9 CFR 417.3 - Corrective actions.
Code of Federal Regulations, 2010 CFR
2010-01-01
... ANALYSIS AND CRITICAL CONTROL POINT (HACCP) SYSTEMS § 417.3 Corrective actions. (a) The written HACCP plan.... The HACCP plan shall describe the corrective action to be taken, and assign responsibility for taking... identified deviation or other unforeseen hazard should be incorporated into the HACCP plan. (c)...
9 CFR 417.3 - Corrective actions.
Code of Federal Regulations, 2011 CFR
2011-01-01
... ANALYSIS AND CRITICAL CONTROL POINT (HACCP) SYSTEMS § 417.3 Corrective actions. (a) The written HACCP plan.... The HACCP plan shall describe the corrective action to be taken, and assign responsibility for taking... identified deviation or other unforeseen hazard should be incorporated into the HACCP plan. (c)...
NASA Astrophysics Data System (ADS)
Roddier, Claude; Roddier, Francois
1990-10-01
Diffraction-limited imaging of unknown objects through fixed unknown aberrations is demonstrated using rotational shear interferograms. Objects are assumed to be fully incoherent. No reference point source is used to calibrate the effects of aberrations. Several algorithms are described, and two are successfully used to reconstruct extended objects. Best results are obtained by combining the two successful ones.
Completion Rates and Accuracy of Performance Under Fixed and Variable Token Exchange Periods.
ERIC Educational Resources Information Center
McLaughlin, T. F.; Malaby, J. E.
This research investigated the effects of employing fixed, variable, and extended token exchange periods for back-ups on the completion and accuracy of daily assignments for a total fifth and sixth-grade class. The results indicated that, in general, a higher percentage of assignments was completed when the number of days between point exchanges…
ERIC Educational Resources Information Center
Torgrud, Laine J.; Holborn, Stephen W.; Zak, Robert D.
2006-01-01
Undergraduates given accurate instructions pressed keys for token points under either a variety of reinforcement schedules (variety training) or under a single schedule. Response rates on a fixed-interval (FI) test schedule then were assessed. Experiment 1 compared variety training inclusive of FI-optimal rates (functional) to training excluding…
ERIC Educational Resources Information Center
Torgrud, Laine J.; Holborn, Stephen W.; Zak, Robert D.
2006-01-01
Undergraduates given accurate instructions pressed keys for token points under either a variety of reinforcement schedules (variety training) or under a single schedule. Response rates on a fixed-interval (FI) test schedule then were assessed. Experiment 1 compared variety training inclusive of FI-optimal rates (functional) to training excluding
Characterizing configurations of fire ignition points through spatiotemporal point processes
NASA Astrophysics Data System (ADS)
Comas, C.; Costafreda-Aumedes, S.; Vega-Garcia, C.
2014-04-01
Human-caused forest fires are usually regarded as unpredictable but often exhibit trends towards clustering in certain locations and periods. Characterizing such configurations is crucial for understanding spatiotemporal fire dynamics and implementing preventive actions. Our objectives were to analyse the spatiotemporal point configuration and to test for spatiotemporal interaction. We characterized the spatiotemporal structure of 984 fire ignition points in a study area of Galicia, Spain, during 2007-2011 by the K-Ripley's function. Our results suggest the presence of spatiotemporal structures for time lags of less than two years and ignition point distances in the range 0-12 km. Ignition centre points at time lags of less than 100 days are aggregated for any inter-event distance. This cluster structure loses strength as the time lag increases, and at time lags of more than 365 days this cluster structure is not significant for any lag distance. Our results also suggest spatiotemporal interdependencies at time lags of less than 100 days and inter-event distances of less than 10 km. At time lags of up to 365 days spatiotemporal components are independent for any point distance. These results suggest that risk conditions occur locally and are short-lived in this study area.
46 CFR 28.260 - Electronic position fixing devices.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 1 2011-10-01 2011-10-01 false Electronic position fixing devices. 28.260 Section 28... Trade § 28.260 Electronic position fixing devices. Each vessel 79 feet (24 meters) or more in length must be equipped with an electronic position fixing device capable of providing accurate fixes for...
46 CFR 28.260 - Electronic position fixing devices.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 1 2010-10-01 2010-10-01 false Electronic position fixing devices. 28.260 Section 28... Trade § 28.260 Electronic position fixing devices. Each vessel 79 feet (24 meters) or more in length must be equipped with an electronic position fixing device capable of providing accurate fixes for...
50 CFR 660.211 - Fixed gear fishery-definitions.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 50 Wildlife and Fisheries 13 2012-10-01 2012-10-01 false Fixed gear fishery-definitions. 660.211... Groundfish-Limited Entry Fixed Gear Fisheries § 660.211 Fixed gear fishery—definitions. These definitions are specific to the limited entry fixed gear fisheries covered in this subpart. General groundfish...
50 CFR 660.211 - Fixed gear fishery-definitions.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 50 Wildlife and Fisheries 13 2014-10-01 2014-10-01 false Fixed gear fishery-definitions. 660.211... Groundfish-Limited Entry Fixed Gear Fisheries § 660.211 Fixed gear fishery—definitions. These definitions are specific to the limited entry fixed gear fisheries covered in this subpart. General groundfish...
50 CFR 660.211 - Fixed gear fishery-definitions.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 50 Wildlife and Fisheries 13 2013-10-01 2013-10-01 false Fixed gear fishery-definitions. 660.211... Groundfish-Limited Entry Fixed Gear Fisheries § 660.211 Fixed gear fishery—definitions. These definitions are specific to the limited entry fixed gear fisheries covered in this subpart. General groundfish...
50 CFR 660.211 - Fixed gear fishery-definitions.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Fixed gear fishery-definitions. 660.211... Groundfish-Limited Entry Fixed Gear Fisheries § 660.211 Fixed gear fishery—definitions. These definitions are specific to the limited entry fixed gear fisheries covered in this subpart. General groundfish...
50 CFR 660.212 - Fixed gear fishery-prohibitions.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Fixed gear fishery-prohibitions. 660.212... Groundfish-Limited Entry Fixed Gear Fisheries § 660.212 Fixed gear fishery—prohibitions. These prohibitions are specific to the limited entry fixed gear fisheries. General groundfish prohibitions are found...
50 CFR 660.219 - Fixed gear identification and marking.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Fixed gear identification and marking. 660... Groundfish-Limited Entry Fixed Gear Fisheries § 660.219 Fixed gear identification and marking. (a) Gear identification. (1) Limited entry fixed gear (longline, trap or pot) must be marked at the surface and at...
Anomalous scaling at nonthermal fixed points of Burgers' and Gross-Pitaevskii turbulence
NASA Astrophysics Data System (ADS)
Mathey, Steven; Gasenzer, Thomas; Pawlowski, Jan M.
2015-08-01
Scaling in the dynamical properties of complex many-body systems has been of strong interest since turbulence phenomena became the subject of systematic mathematical studies. In this article, dynamical critical phenomena far from equilibrium are investigated with functional renormalization-group equations. The focus is set on scaling solutions of the stochastic driven-dissipative Burgers equation and their relation to solutions known in the literature for Burgers' and Kardar-Parisi-Zhang dynamics. We furthermore relate superfluid as well as acoustic turbulence described by the Gross-Pitaevskii model to known analytic and numerical results for scaling solutions. In this way, the canonical Kolmogorov exponent 5/3 for the energy cascade in superfluid turbulence is obtained analytically. We also get results for anomalous exponents of acoustic and quantum turbulence. These are consistent with existing experimental data. Our results should be relevant for future experiments with, e.g., exciton-polariton condensates in solid-state systems as well as with ultracold atomic gases.
Balance between absorbing and positive fixed points in resource consumption models
NASA Astrophysics Data System (ADS)
Behar, Hilla; Shnerb, Nadav; Louzoun, Yoram
2012-09-01
The effect of resource usage on economic growth has been studied in multiple models. However, the generic effect of improving resource usage efficacy through improved technical skills has not been studied in detail. We here analyze a model incorporating resource usage by capital and the parallel production of technical skill in order to study the effect of improving the efficacy of resources usage with advanced technologies. We show that a practically inevitable result of such a model is that improving the resource usage efficacy leads to a lower steady-state level of resources. A surprising conclusion from ordinary differential equations realization of the model is an extreme sensitivity to parameters, where a small parameter change can lead to an irreversible state through a hysteresis mechanism between a scenario of a collapse of the economy and a scenario of sustainable economy. This sensitivity is lost when spatial stochastic simulations are performed. In the stochastic regime the two scenarios coexist, with different fractions of the lattice residing in each state. Changing parameters smoothly changes the fraction of lattice sites in each state. The transition between the collapsed economy and the sustainable one is not symmetrical. Escape from the collapsed situation can only occur through diffusion from neighboring sustained lattice sites. On the other hand, the collapse can occur even in the absence of diffusion. This difference leads to diffusion dependent capital growth, where an optimal capital is obtained for middiffusion values. Such a transition may actually be generic phenomena in ecological and economic systems.
NASA Astrophysics Data System (ADS)
López-Gómez, Julián; Molina-Meyer, Marcela
In this work a general class of nonlinear abstract equations satisfying a generalized strong maximum principle is considered in order to study the behavior of the bounded components of positive solutions bifurcating from the curve of trivial states (λ,u)=(λ,0) at a nonlinear eigenvalue λ=λ0 with geometric multiplicity one. Since the unilateral theorems of Rabinowitz (J. Funct. Anal. 7 (1971) 487, Theorems 1.27 and 1.40) are not true as originally stated (cf. the very recent counterexample of Dancer, Bull. London Math. Soc. 34 (2002) 533), in order to get our main results the unilateral theorem of López-Gómez (Spectral Theory and Nonlinear Functional Analysis, Research Notes in Mathematics, vol. 426, CRC Press, Boca Raton, FL, 2001, Theorem 6.4.3) is required. Our analysis fills some serious gaps existing is some published papers that were provoked by a direct use of Rabinowitz's unilateral theory. Actually, the abstract theory developed in this paper cannot be covered with the pioneering results of Rabinowitz (1971), since in Rabinowitz's context any component of positive solutions must be unbounded, by a celebrated result attributable to Dancer (Arch. Rational Mech. Anal. 52 (1973) 181).
Final Report for "Infrared Fixed Points in Multiflavor Lattice Gauge Theory"
Meurice, Yannick; Sinclair, Donald K.
2013-09-27
The goal of the grant was to apply methods that we have developed with spin and pure gauge models to models with dynamical fermions which are considered as candidates for an alternative to the Higgs mechanism. The work on SU(3) with fundamental quarks and with sextet quarks is described.
Differential optical absorption spectrometry (DOAS) has been used by a number of investigators over the past 10 years to measure a wide range of gaseous air pollutants. ecently OPSIS AB, Lund, Sweden, has developed and made commercially available DOAS instrument that has a number...
Herrera-Aguilar, José L.; Larralde, Hernán; Aldana, Maximino
2012-01-01
We study the properties of the dynamical phase transition occurring in neural network models in which a competition between associative memory and sequential pattern recognition exists. This competition occurs through a weighted mixture of the symmetric and asymmetric parts of the synaptic matrix. Through a generating functional formalism, we determine the structure of the parameter space at non-zero temperature and near saturation (i.e., when the number of stored patterns scales with the size of the network), identifying the regions of high and weak pattern correlations, the spin-glass solutions, and the order-disorder transition between these regions. This analysis reveals that, when associative memory is dominant, smooth transitions appear between high correlated regions and spurious states. In contrast when sequential pattern recognition is stronger than associative memory, the transitions are always discontinuous. Additionally, when the symmetric and asymmetric parts of the synaptic matrix are defined in terms of the same set of patterns, there is a discontinuous transition between associative memory and sequential pattern recognition. In contrast, when the symmetric and asymmetric parts of the synaptic matrix are defined in terms of independent sets of patterns, the network is able to perform both associative memory and sequential pattern recognition for a wide range of parameter values. PMID:22900014
ERIC Educational Resources Information Center
Shih, Ching-Hsiang; Hsu, Nai-Yun; Shih, Ching-Tien
2009-01-01
This study evaluated whether two children with developmental disabilities would be able to improve their pointing performance through an Automatic Pointing Assistive Program (APAP) and a newly developed mouse driver (i.e. a new mouse driver replaces standard mouse driver, and is able to intercept mouse click action). Initially, both participants
The probability that an element of a metacylic 3-group fixes a set of size three
NASA Astrophysics Data System (ADS)
Zamri, Siti Norziahidayu Amzee; Sarmin, Nor Haniza; Omer, Sanaa Mohamed Saleh
2016-02-01
Let G be a metacylic 3-group of negative type of nilpotency class at least three. In this paper, Ω is a set of all subsets of all commuting elements of G of size three in the form of (a,b), where a and b commute. The probability that an element of a group G fixes a set Ω is one of extensions of the commutativity degree that can be obtained under group action on set. This probability is the ratio of the number of orbits to the order of Ω. In this paper, the probability that an element of a group G fixes a set Ω is computed by using conjugate action.
Discrete and cyclical units of action in a mixed target pair aiming task.
Buchanan, John J; Park, Jin-H; Ryu, Young U; Shea, Charles H
2003-06-01
Two experiments addressed the issue of discrete and cyclical units as possible basic units of action that might be used to construct complex actions based on task constraints. The experiments examined the influence of low and high accuracy constraints on the end-effector's motion in rhythmical aiming movements. Both experiments utilized a Fitts-type task under three accuracy constraints: (1) big target pairing-low index of movement difficulty (ID), (2) small target pairing-high ID, and (3) mixed target pairing-one target high ID and the other target low ID. Experiment I was a 1-degree-of-freedom ( df) task that required subjects to crossover the inside edge of targets in a target pair using elbow flexion-extension motions. Experiment II used a 2- df task that required subjects to tap back and forth between targets in a target pair using a hand-held stylus. In both experiments, end-effector motion in the low ID condition was cyclical with the end-effector's motion consistent with a limit-cycle attractor description, while in the high ID condition end-effector motion was discrete and consistent with a fixed-point attractor description. The mixed target pairing produced both discrete and cyclical features in the end-effector's dynamics that suggested a functional linking of discrete and cyclical units of action as the optimal movement solution. Evidence supporting the above statements was found in the kinematic measures of movement time (MT), dwell time, proportion of MT accelerating and decelerating, and in a measure of harmonicity (Guiard 1993, Acta Psychol 82:139-159; Guiard 1997, Hum Mov Sci 16:97-131). Extended practice in the mixed target condition revealed a bias towards cyclical motion with practice. The results demonstrate that discrete and cyclical motion, represented as limit-cycle and fixed-point attractors, are basic units of action that the motor system uses in constructing more complex action sequences. The results are discussed with reference to coordinative structures and the generalized motor program as basic units of action. Issues pertaining to visual feedback processing and movement braking in rapid aiming tasks are also discussed. PMID:12739091
Suppression of fixed pattern noise for infrared image system
NASA Astrophysics Data System (ADS)
Park, Changhan; Han, Jungsoo; Bae, Kyung-Hoon
2008-04-01
In this paper, we propose suppression of fixed pattern noise (FPN) and compensation of soft defect for improvement of object tracking in cooled staring infrared focal plane array (IRFPA) imaging system. FPN appears an observable image which applies to non-uniformity compensation (NUC) by temperature. Soft defect appears glittering black and white point by characteristics of non-uniformity for IR detector by time. This problem is very important because it happen serious problem for object tracking as well as degradation for image quality. Signal processing architecture in cooled staring IRFPA imaging system consists of three tables: low, normal, high temperature for reference gain and offset values. Proposed method operates two offset tables for each table. This is method which operates six term of temperature on the whole. Proposed method of soft defect compensation consists of three stages: (1) separates sub-image for an image, (2) decides a motion distribution of object between each sub-image, (3) analyzes for statistical characteristic from each stationary fixed pixel. Based on experimental results, the proposed method shows an improved image which suppresses FPN by change of temperature distribution from an observational image in real-time.
Parallel genetic algorithms for large-scale fixed charge networks
Meyer, R.R.
1994-12-31
We present parallel genetic algorithms (GA`s) for several classes of fixed-charge multicommodity flow problems arising from applications in parallel database design, domain decomposition, and telecommunications. These algorithms utilize a high-level approach based upon representing individual (in the GA sense) in terms of selections from a library of pre-computed {open_quotes}building blocks{close_quotes} of sets of variables rather than as values of individual binary variables corresponding to single links. The fitness function for this form of representation is then evaluated by applying heuristics to the starting point represented by an individual, thereby allowing for modifications in the original {open_quotes}blueprint{close_quotes} represented by the individual. These heuristics lead to objective function improvements and are also used to force feasibility. With this type of fitness function, the amount of time spent on the other operations of the GA (selection, mutation, etc.) is relatively small, so that high efficiency may be achieved in parallel implementations of the algorithm. We present computational results on the CM-5 supercomputer, demonstrating the ability to solve to optimality certain fixed-charge problems with more than one million binary variables.
Fixed target electroweak and hard scattering physics
Brock, R. ); Brown, C.N.; Montgomery, H.E. ); Corcoran, M.D. )
1990-02-01
The possibilities for future physics and experiments involving weak and electromagnetic interactions, neutrino oscillations, general hard scattering and experiments involving nuclear targets were explored. The studies were limited to the physics accessible using fixed target experimentation. While some of the avenues explored turn out to be relatively unrewarding in the light of competition elsewhere in the world, there are a number of positive conclusions reached about experimentation in the energy range available to the Main Injector and Tevatron. Some of the experiments would benefit from the increased intensity available from the Tevatron utilizing the Main Injector, while some require this increase. Finally, some of the experiments would use the Main Injector low energy, high intensity extracted beams directly. A program of electroweak and hard scattering experiments at fixed target energies retains the potential for important contributions to physics. The key to major parts of this program would appear to be the existence of the Main Injector. 115 refs, 17 figs.
Fixing the Shadows While Moving the Gnomon
NASA Astrophysics Data System (ADS)
Gangui, Alejandro
2015-04-01
It is a common practice to fix a vertical gnomon and study the moving shadow cast by it. This shows our local solar time and gives us a hint regarding the season in which we perform the observation. The moving shadow can also tell us our latitude with high precision. In this paper we propose to exchange the roles and while keeping the shadows fixed on the ground we will move the gnomon. This lets us understand in a simple way the relevance of the tropical lines of latitude and the behavior of shadows in different locations. We then put these ideas into practice using sticks and threads during a solstice on two sites located on opposite sides of the Tropic of Capricorn.
Preliminary investigation of pilot scanning techniques of dial pointing instruments
NASA Technical Reports Server (NTRS)
Harris, R. L., Sr.
1979-01-01
Two pilots' methods of looking at instruments with needle pointers in a fixed base helicopter simulation were observed. A total of 45 runs were analyzed for each pilot. The data indicated that two apparently different techniques were being used; one looking at the needle point, the other looking at a fixed spot on the instrument and reading the needle direction parafoveally. The latter technique is found to be somewhat faster with both pilots accomplishing the flying task.
Single chip fixed frequency bit synchronizer
NASA Technical Reports Server (NTRS)
Butler, Madeline J.; James, Calvin L.
1989-01-01
A single chip, fixed frequency suboptimum bit synchronizer design which was implemented utilizing a programmable logic device is described. The bit synchronizer is modeled after a digital transition tracking loop for symbol estimation and employs a first-order incremental phase modulator for closed-loop symbol synchronization. The BER and tracking performance is modeled and compared to optimum designs. The bit synchronizer was developed for the Space Shuttle.
Azithromycin induced bullous fixed drug eruption
Das, Anupam; Sancheti, Karan; Podder, Indrashis; Das, Nilay Kanti
2016-01-01
Fixed drug eruption (FDE) is a common type of drug eruption seen in skin clinics. It is characterized by solitary or multiple, round to oval erythematous patches with dusky red centers, some of which may progress to bulla formation. Bullous FDE may be caused by a number of drugs. We hereby describe a case of azithromycin-induced bullous FDE; to the best of our knowledge, this is the first such case being reported.
Fixed drug eruptions with intraoral presentation
Srivastava, Rahul; Bihari, Manorama; Bhuvan, Jyoti; Saad, Ahmed
2015-01-01
Fixed-drug eruption (FDE) is an unusual and rare adverse drug reaction. This type of reaction is actually a delayed type of hypersensitivity reaction that occurs as lesions recurring at the same skin site due to repeated intake of an offending drug. Here is a case report of a 58-year-old male patient who developed intraoral FDEs after ingestion of the first dose of ornidazole. PMID:26097341
Acemetacin-induced fixed drug eruption
Cebeci, Filiz; Yaşar, Şirin; Aytekin, Sema; Güneş, Pembegül
2016-01-01
Fixed drug eruption (FDE) is an adverse effect observed with various drugs such as nonsteroidal anti-inflammatory drugs (NSAIDs) and various antibiotics. Acemetacin, a prodrug of indomethacin, is an NSAID licensed for use in rheumatic disease and other musculoskeletal disorders. We present a case of acemetacin-induced FDE in a 49-year-old woman. To the best of our knowledge, this is the second case report detailing clinical and histopathological findings of a patient with FDE caused by acemetacin.
Fuel optimal maneuvers for spacecraft with fixed thrusters
NASA Technical Reports Server (NTRS)
Carter, T. C.
1982-01-01
Several mathematical models, including a minimum integral square criterion problem, were used for the qualitative investigation of fuel optimal maneuvers for spacecraft with fixed thrusters. The solutions consist of intervals of "full thrust" and "coast" indicating that thrusters do not need to be designed as "throttleable" for fuel optimal performance. For the primary model considered, singular solutions occur only if the optimal solution is "pure translation". "Time optimal" singular solutions can be found which consist of intervals of "coast" and "full thrust". The shape of the optimal fuel consumption curve as a function of flight time was found to depend on whether or not the initial state is in the region admitting singular solutions. Comparisons of fuel optimal maneuvers in deep space with those relative to a point in circular orbit indicate that qualitative differences in the solutions can occur. Computation of fuel consumption for certain "pure translation" cases indicates that considerable savings in fuel can result from the fuel optimal maneuvers.
Fixed-Functionals of three-dimensional Quantum Einstein Gravity
NASA Astrophysics Data System (ADS)
Demmel, Maximilian; Saueressig, Frank; Zanusso, Omar
2012-11-01
We study the non-perturbative renormalization group flow of f ( R)-gravity in three-dimensional Asymptotically Safe Quantum Einstein Gravity. Within the conformally reduced approximation, we derive an exact partial differential equation governing the RG-scale dependence of the function f ( R). This equation is shown to possess two isolated and one continuous one-parameter family of scale-independent, regular solutions which constitute the natural generalization of RG fixed points to the realm of infinite-dimensional theory spaces. All solutions are bounded from below and give rise to positive definite kinetic terms. Moreover, they admit either one or two UV-relevant deformations, indicating that the corresponding UV-critical hypersurfaces remain finite dimensional despite the inclusion of an infinite number of coupling constants. The impact of our findings on the gravitational Asymptotic Safety program and its connection to new massive gravity is briefly discussed.
Braun, Daniel A; Mehring, Carsten; Wolpert, Daniel M
2010-01-20
'Learning to learn' phenomena have been widely investigated in cognition, perception and more recently also in action. During concept learning tasks, for example, it has been suggested that characteristic features are abstracted from a set of examples with the consequence that learning of similar tasks is facilitated-a process termed 'learning to learn'. From a computational point of view such an extraction of invariants can be regarded as learning of an underlying structure. Here we review the evidence for structure learning as a 'learning to learn' mechanism, especially in sensorimotor control where the motor system has to adapt to variable environments. We review studies demonstrating that common features of variable environments are extracted during sensorimotor learning and exploited for efficient adaptation in novel tasks. We conclude that structure learning plays a fundamental role in skill learning and may underlie the unsurpassed flexibility and adaptability of the motor system. PMID:19720086
RSRM nozzle fixed housing cooldown test
NASA Technical Reports Server (NTRS)
Bolieau, D. J.
1989-01-01
Flight 5 aft segments with nozzles were exposed to -17 F temperatures while awaiting shipment to KSC in February, 1989. No records were found which show that any previous nozzles were exposed to air temperatures as low as those seen by the Flight 5 nozzles. Thermal analysis shows that the temperature of the fixed housing, and forward and aft exit cone components dropped as low as -10 F. Structural analysis of the nozzles at these low temperatures show the forward and aft exit cone adhesive bonds to have a positive margin of safety, based on a 2.0 safety factor. These analyses show the normal and shear stresses in the fixed housing bond as low values. However, the hoop and meridinal stresses were predicted to be in the 4000 psi range; the failure stress allowable of EA913NA adhesive at -7 F. If the bonds did break in directions perpendicular to the surfaces, called bond crazing, no normal bond strength would be lost. Testing was conducted in two phases, showing that no degradation to the adhesive bonds occurred while the Flight 5 nozzles were subjected to subzero temperatures. The results of these tests are documented. Phase 1 testing cooled a full-scale RSRM insulated fixed housing to -13 F, with extensive bondline inspections. Phase 2 testing cooled the witness panel adhesive tensile buttions to -13 F, with failure strengths recorded before, during, and after the cooldown.
Zirconia in fixed prosthesis. A literature review
Román-Rodríguez, Juan L.; Ferreiroa, Alberto; Solá-Ruíz, María F.; Fons-Font, Antonio
2014-01-01
Statement of problem: Evidence is limited on the efficacy of zirconia-based fixed dental prostheses. Objective: To carry out a literature review of the behavior of zirconium oxide dental restorations. Material and Methods: This literature review searched the Pubmed, Scopus, Medline and Cochrane Library databases using key search words “zirconium oxide,” “zirconia,” “non-metal restorations,” “ceramic oxides,” “veneering ceramic,” “zirconia-based fixed dental prostheses”. Both in vivo and in vitro studies into zirconia-based prosthodontic restoration behavior were included. Results: Clinical studies have revealed a high rate of fracture for porcelain-veneered zirconia-based restorations that varies between 6% and 15% over a 3- to 5-year period, while for ceramo-metallic restorations the fracture rate ranges between 4 and 10% over ten years. These results provoke uncertainty as to the long-term prognosis for this material in the oral medium. The cause of veneering porcelain fractures is unknown but hypothetically they could be associated with bond failure between the veneer material and the zirconia sub-structure. Key words:Veneering ceramic, zirconia-based ceramic restoration, crown, zirconia, tooth-supported fixed prosthesis. PMID:24596638
Fixed-interval and fixed-ratio reinforcement schedules with human subjects.
Stoddard, L T; Sidman, M; Brady, J V
1988-01-01
Operant laboratory studies were conducted as part of the regular activities of a psychiatric research ward. This report includes only some early data obtained from the ward staff, not the patients. A multiple schedule having alternating fixed-ratio and fixed-interval components permitted observations of acquisition and maintenance of behavior at low schedule values, transition to and final performance at greater schedule values, and behavioral changes after a limited-hold contingency was added to the fixed-interval. Prior to the added limited-hold, subjects used watches to time the interval, and usually responded only once before obtaining each fixed-interval reinforcement. Short limited-hold values eliminated clock watching and increased fixed-interval responding. Subjects communicated freely with each other, and it was clear that their performances were controlled both by the contingencies and by instructions. Just as clearly, the instructions themselves were controlled by the contingencies. It was concluded that the kinds of verbal control that were responsible for "nonstandard" fixed-interval performances did not require the postulation of any new behavioral principles. PMID:22477562
Fixed-interval and fixed-ratio reinforcement schedules with human subjects
Stoddard, Lawrence T.; Sidman, Murray; Brady, Joseph V.
1988-01-01
Operant laboratory studies were conducted as part of the regular activities of a psychiatric research ward. This report includes only some early data obtained from the ward staff, not the patients. A multiple schedule having alternating fixed-ratio and fixed-interval components permitted observations of acquisition and maintenance of behavior at low schedule values, transition to and final performance at greater schedule values, and behavioral changes after a limited-hold contingency was added to the fixed-interval. Prior to the added limited-hold, subjects used watches to time the interval, and usually responded only once before obtaining each fixed-interval reinforcement. Short limited-hold values eliminated clock watching and increased fixed-interval responding. Subjects communicated freely with each other, and it was clear that their performances were controlled both by the contingencies and by instructions. Just as clearly, the instructions themselves were controlled by the contingencies. It was concluded that the kinds of verbal control that were responsible for “nonstandard” fixed-interval performances did not require the postulation of any new behavioral principles. PMID:22477562
Ellipsoidal Effects in the Fixed Geodetic Boundary Value Problem
NASA Astrophysics Data System (ADS)
Heck, Bernhard; Seitz, Kurt
2014-05-01
After applying topographic reductions and downward continuation on the observed boundary data the linearized Geodetic Boundary Value Problem (GBVP) degenerates into an ellipsoidal problem. Although the ellipsoidal boundary surface possesses a much simpler topology than the original topographical surface of the Earth, this simplified problem still cannot be solved in an elementary analytical way; in contrast, the "simple" GBVP related to a spherical boundary surface and the normal (radial) derivative is rigorously solvable by spherical integral formulae. In the past, various approaches have been developed for approximate solutions of the ellipsoidal GBVP, starting from the classical work by Sagrebin (1956). These approaches, mainly applied to the free GBVP, rely on first order approximations with respect to the flattening of the ellipsoid of revolution and can be subdivided in three groups. The first group is based on modifications of the spherical integral kernel, resulting in anisotropic kernel functions depending on the azimuth between the computation point and the moving integration point. In the second group the boundary data are reduced for "ellipsoidal effects" and inserted into spherical integral formulae. Finally, in the third group the ellipsoidal boundary data is formally inserted into the spherical solution formula, and a correction term is added for consideration of the ellipsoidal effect. An advantage of the third approach, propagated by Heck and Seitz (2003) for the linearized scalar-free GBVP, consists in the fact that the correction term can easily be evaluated from some global geopotential model in the form of a spherical harmonic series. In the paper the three groups of approaches are discussed for the case of the fixed GBVP. A first-order solution of the fixed GBVP related to an ellipsoidal boundary is derived in detail according to the procedure presented in Heck and Seitz (2003). Finally, the resulting ellipsoidal correction term is investigated numerically in the space as well as in the frequency domain.
Medical education: hitting the target but missing the point.
Walsh, Kieran
2015-11-01
There are dangers that a target-driven culture could be affecting medical education. In continuous professional development, many accreditation authorities require physicians to complete a fixed number of hours of continuous professional development per year or to acquire a certain amount of continuous professional development points per year. However, all these numbers are arbitrary and worse reinforce the message to physicians that it is time spent on learning that is important. In fact far more important than hours spent is the ability to assess learning needs, learn in the light of these needs and put learning into action. Targets have also started to come to the fore is in undergraduate and postgraduate training programmes, and in certain clinical topics such as dementia and in workforce development. Targets in any walk of life should be SMART - that is specific, measurable, achievable, realistic and time limited. However, not all targets in medical education satisfy these criteria of good-quality targets. There is also the wider question as to whether there is a good fit between medical education - which is largely a qualitative activity - and educational targets - which by their nature must be quantitative. Put simply, targets may not fit with education. PMID:26808931
Floating Point Control Library
Energy Science and Technology Software Center (ESTSC)
2007-08-02
Floating Point Control is a Library that allows for the manipulation of floating point unit exception masking funtions control exceptions in both the Streaming "Single Instruction, Multiple Data" Extension 2 (SSE2) unit and the floating point unit simultaneously. FPC also provides macros to set floating point rounding and precision control.
A complete and explicit solution to the three-dimensional problem of two fixed centres
NASA Astrophysics Data System (ADS)
Biscani, Francesco; Izzo, Dario
2016-02-01
We present for the first time an explicit, complete and closed-form solution to the three-dimensional problem of two fixed centres, based on Weierstrass elliptic and related functions. With respect to previous treatments of the problem, our solution is exact, valid for all initial conditions and physical parameters of the system (including unbounded orbits and repulsive forces), and expressed via a unique set of formulae. Various properties of the three-dimensional problem of two fixed centres are investigated and analysed, with a particular emphasis on quasi-periodic and periodic orbits, regions of motion and equilibrium points.
Myofascial trigger point pain.
Jaeger, Bernadette
2013-01-01
Myofascial trigger point pain is an extremely prevalent cause of persistent pain disorders in all parts of the body, not just the head, neck, and face. Features include deep aching pain in any structure, referred from focally tender points in taut bands of skeletal muscle (the trigger points). Diagnosis depends on accurate palpation with 2-4 kg/cm2 of pressure for 10 to 20 seconds over the suspected trigger point to allow the referred pain pattern to develop. In the head and neck region, cervical muscle trigger points (key trigger points) often incite and perpetuate trigger points (satellite trigger points) and referred pain from masticatory muscles. Management requires identification and control of as many perpetuating factors as possible (posture, body mechanics, psychological stress or depression, poor sleep or nutrition). Trigger point therapies such as spray and stretch or trigger point injections are best used as adjunctive therapy. PMID:24864393
Final consolidated action plan to Tiger Team. Volume 1
Not Available
1992-10-01
This document contains the planned actions to correct the deficiences identified in the Tiger Team Assessments of Sandia California (August 1990) and Sandia New Mexico (May 1991). Information is also included on the management structures, estimated costs, root causes, prioritization and schedules for the Action Plan. This Plan is an integration of the two individual Action Plans to provide a cost effective, integrated program for implementation by Sandia and monitoring by DOE. This volume (I) contains the findings and actions concerning the environment. Tables 4.2 and 4.7 summarize the annual costs estimated for completing the actions. The total costs for completion of all the actions are estimated to be $283 million over a 12 year period; the majority of the actions to be completed and costs incurred in the first five years. Resources are provided from DOE-ER/WM, the DOE/DP landlord funds (one time, physical fixes), and from the Sandia Indirect Budget.
Wagle, Nikhil; Berger, Michael F.; Davis, Matthew J.; Blumenstiel, Brendan; DeFelice, Matthew; Pochanard, Panisa; Ducar, Matthew; Van Hummelen, Paul; MacConaill, Laura E.; Hahn, William C.; Meyerson, Matthew; Gabriel, Stacey B.; Garraway, Levi A.
2011-01-01
Knowledge of “actionable” somatic genomic alterations present in each tumor (e.g., point mutations, small insertions/deletions, and copy number alterations that direct therapeutic options) should facilitate individualized approaches to cancer treatment. However, clinical implementation of systematic genomic profiling has rarely been achieved beyond limited numbers of oncogene point mutations. To address this challenge, we utilized a targeted, massively parallel sequencing approach to detect tumor genomic alterations in formalin-fixed, paraffin embedded (FFPE) tumor samples. Nearly 400-fold mean sequence coverage was achieved, and single nucleotide sequence variants, small insertions/deletions, and chromosomal copy number alterations were detected simultaneously with high accuracy compared to other methods in clinical use. Putatively actionable genomic alterations, including those that predict sensitivity or resistance to established and experimental therapies, were detected in each tumor sample tested. Thus, targeted deep sequencing of clinical tumor material may enable mutation-driven clinical trials and, ultimately, ”personalized” cancer treatment. PMID:22585170
Metabolic syndrome in fixed-shift workers
Canuto, Raquel; Pattussi, Marcos Pascoal; Macagnan, Jamile Block Araldi; Henn, Ruth Liane; Olinto, Maria Teresa Anselmo
2015-01-01
OBJECTIVE To analyze if metabolic syndrome and its altered components are associated with demographic, socioeconomic and behavioral factors in fixed-shift workers. METHODS A cross-sectional study was conducted on a sample of 902 shift workers of both sexes in a poultry processing plant in Southern Brazil in 2010. The diagnosis of metabolic syndrome was determined according to the recommendations from Harmonizing the Metabolic Syndrome. Its frequency was evaluated according to the demographic (sex, skin color, age and marital status), socioeconomic (educational level, income and work shift), and behavioral characteristics (smoking, alcohol intake, leisure time physical activity, number of meals and sleep duration) of the sample. The multivariate analysis followed a theoretical framework for identifying metabolic syndrome in fixed-shift workers. RESULTS The prevalence of metabolic syndrome in the sample was 9.3% (95%CI 7.4;11.2). The most frequently altered component was waist circumference (PR 48.4%; 95%CI 45.5;51.2), followed by high-density lipoprotein. Work shift was not associated with metabolic syndrome and its altered components. After adjustment, the prevalence of metabolic syndrome was positively associated with women (PR 2.16; 95%CI 1.28;3.64), workers aged over 40 years (PR 3.90; 95%CI 1.78;8.93) and those who reported sleeping five hours or less per day (PR 1.70; 95%CI 1.09;2.24). On the other hand, metabolic syndrome was inversely associated with educational level and having more than three meals per day (PR 0.43; 95%CI 0.26;0.73). CONCLUSIONS Being female, older and deprived of sleep are probable risk factors for metabolic syndrome, whereas higher educational level and higher number of meals per day are protective factors for metabolic syndrome in fixed-shift workers. PMID:26061455
Impaired Inhibitory Force Feedback in Fixed Dystonia.
Mugge, Winfred; Schouten, Alfred C; van Hilten, Jacobus J; van der Helm, Frans C T
2016-04-01
Complex regional pain syndrome (CRPS) is a multifactorial disorder associated with an aberrant host response to tissue injury. About 25% of CRPS patients suffer poorly understood involuntary sustained muscle contractions associated with dysfunctional reflexes that result in abnormal postures (fixed dystonia). A recent modeling study simulated fixed dystonia (FD) caused by aberrant force feedback. The current study aims to validate this hypothesis by experimentally recording the modulation of reflexive force feedback in patients with FD. CRPS patients with and without FD, patients with FD but without CRPS, as well as healthy controls participated in the experiment. Three task instructions and three perturbation characteristics were used to evoke a wide range of responses to force perturbations. During position tasks ("maintain posture"), healthy subjects as well as patients resisted the perturbations, becoming more stiff than when being relaxed (i.e., the relax task). Healthy subjects and CRPS patients without FD were both more compliant during force tasks ("maintain force") than during relax tasks, meaning they actively gave way to the imposed forces. Remarkably, the patients with FD failed to do so. A neuromuscular model was fitted to the experimental data to separate the distinct contributions of position, velocity and force feedback, as well as co-contraction to the motor behavior. The neuromuscular modeling indicated that inhibitory force feedback is deregulated in patients with FD, for both CRPS and non-CRPS patients. From previously published simulation results and the present experimental study, it is concluded that aberrant force feedback plays a role in fixed dystonia. PMID:25955788
Simulating murder: the aversion to harmful action.
Cushman, Fiery; Gray, Kurt; Gaffey, Allison; Mendes, Wendy Berry
2012-02-01
Diverse lines of evidence point to a basic human aversion to physically harming others. First, we demonstrate that unwillingness to endorse harm in a moral dilemma is predicted by individual differences in aversive reactivity, as indexed by peripheral vasoconstriction. Next, we tested the specific factors that elicit the aversive response to harm. Participants performed actions such as discharging a fake gun into the face of the experimenter, fully informed that the actions were pretend and harmless. These simulated harmful actions increased peripheral vasoconstriction significantly more than did witnessing pretend harmful actions or to performing metabolically matched nonharmful actions. This suggests that the aversion to harmful actions extends beyond empathic concern for victim harm. Together, these studies demonstrate a link between the body and moral decision-making processes. PMID:21910540
Fixing the Closed Orbits in the Debuncher
Halling, Mike
1991-04-05
Without a large number of new trims the best way to fix the closed orbits in the debuncher is to move quads. There are some obvious features in the vertical orbit, Figure 1, that look like they are indeed orbit distortions. The horizontal orbit, Figure 2, also has some systematic features that can be removed by moving a small number of quads. It is likely that removing these orbit distortions will help in improving the aperture. In addition, the second order effects of such large offsets in the closed orbit, like changes in phase advance due to the sextapoles, could improve operations.
Fixed Or Controlled-Movement Foot Restraint
NASA Technical Reports Server (NTRS)
Reilly, Gloria B.; Blizzard, Noah
1992-01-01
Foot restraint gives user three options: holds user's feet in fixed position, allows them to slide sideways, or allows them to pivot independently about axis through ball of foot, as user chooses. Selects degree of restraint to suit task at hand. Movements to enter and leave foot restraint simple and direct. Simply forces each cleat lightly into space between rails until spring force of movable rail secures it. Body movements for sliding and rotation equally straightforward. Designed for use in absence of gravitation, restraint useful on Earth, underwater or in some hazardous locations where movements restricted.
Fixed Target Beauty Physics Experimental Programs
Garbincius, P.H.
1987-11-01
The current and near term future fixed target physics efforts in observing particles with open beauty are reviewed. This includes a compilation of the non-observation upper limits and the observation of both upsilon and b-states. A short discussion of the theoretical predictions for the hadro-produced beauty pairs is included. The major part of this review is devoted to the techniques and tricks employed, a survey of the current and proposed experiments. A personal summary of the experimental prospects concludes this report. 28 refs., 26 figs.
ERIC Educational Resources Information Center
Feldt, Leonard S.
This paper considers, from a theoretical point of view, two measurement approaches used in measuring success and failure in skills tests in physical education. The first, "fixed length" (FL) testing, entails counting the number of successful performances in a fixed number of trials. The second, "trials-to-criterion" (TTC) testing, involves…
Prakash, A.; Bendale, P.G.
1991-12-01
This work is a comparative evaluation of slurry reactors and fixed-bed reactors, with special emphasis on cost. Relative differences between slurry reactors and fixed-bed reactors have been pointed out in previous reviews; the differences pertinent to indirect liquefaction are summarized here. Design of both types is outlined.
ERIC Educational Resources Information Center
Mumford, Alan, Ed.
This book contains 34 papers examining the theory, process, and outcomes of action learning at work. The following papers are included: "An Introduction to the Text" (Alan Mumford); "The Learning Equation" (Reg Revans); "Action Learning as a Vehicle for Learning" (Alan Mumford); "Placing Action Learning and Action Research in Context" (Cliff
ERIC Educational Resources Information Center
Mumford, Alan, Ed.
This book contains 34 papers examining the theory, process, and outcomes of action learning at work. The following papers are included: "An Introduction to the Text" (Alan Mumford); "The Learning Equation" (Reg Revans); "Action Learning as a Vehicle for Learning" (Alan Mumford); "Placing Action Learning and Action Research in Context" (Cliff…
When water does not boil at the boiling point.
Chang, Hasok
2007-03-01
Every schoolchild learns that, under standard pressure, pure water always boils at 100 degrees C. Except that it does not. By the late 18th century, pioneering scientists had already discovered great variations in the boiling temperature of water under fixed pressure. So, why have most of us been taught that the boiling point of water is constant? And, if it is not constant, how can it be used as a 'fixed point' for the calibration of thermometers? History of science has the answers. PMID:17336380
Ash level meter for a fixed-bed coal gasifier
Fasching, George E.
1984-01-01
An ash level meter for a fixed-bed coal gasifier is provided which utilizes the known ash level temperature profile to monitor the ash bed level. A bed stirrer which travels up and down through the extent of the bed ash level is modified by installing thermocouples to measure the bed temperature as the stirrer travels through the stirring cycle. The temperature measurement signals are transmitted to an electronic signal process system by an FM/FM telemetry system. The processing system uses the temperature signals together with an analog stirrer position signal, taken from a position transducer disposed to measure the stirrer position to compute the vertical location of the ash zone upper boundary. The circuit determines the fraction of each total stirrer cycle time the stirrer-derived bed temperature is below a selected set point, multiplies this fraction by the average stirrer signal level, multiplies this result by an appropriate constant and adds another constant such that a 1 to 5 volt signal from the processor corresponds to a 0 to 30 inch span of the ash upper boundary level. Three individual counters in the processor store clock counts that are representative of: (1) the time the stirrer temperature is below the set point (500.degree. F.), (2) the time duration of the corresponding stirrer travel cycle, and (3) the corresponding average stirrer vertical position. The inputs to all three counters are disconnected during any period that the stirrer is stopped, eliminating corruption of the measurement by stirrer stoppage.
47 CFR 22.1031 - Temporary fixed stations.
Code of Federal Regulations, 2011 CFR
2011-10-01
... MOBILE SERVICES Offshore Radiotelephone Service § 22.1031 Temporary fixed stations. The FCC may, upon proper application therefor, authorize the construction and operation of temporary fixed stations in...
47 CFR 22.1031 - Temporary fixed stations.
Code of Federal Regulations, 2010 CFR
2010-10-01
... MOBILE SERVICES Offshore Radiotelephone Service § 22.1031 Temporary fixed stations. The FCC may, upon... Offshore Radiotelephone service to be used only when the service of permanent fixed stations is...
[Fiber-reinforced composite in fixed prosthodontics].
Pilo, R; Abu Rass, Z; Shmidt, A
2010-07-01
Fiber reinforced composite (FRC) is composed of resin matrix and fibers filler. Common types of fibers: polyethylene, carbon and glass. Fibers can be continuous and aligned, discontinuous and aligned, discontinuous and randomly oriented. The architecture of the fibers is unidirectional, woven or braided. The two main types are: dry fibers or impregnated. Inclusion of fibers to resin composite increased its average flexural strength in 100-200 MPa. FRC can be utilized by the dentist in direct approach (splinting, temporary winged bridge) or indirect approach (laboratory made fixed partial denture). Laboratory fixed partial denture (FPD) is made from FRC substructure and Hybrid/Microfill particulate composite veneer. Main indications: interim temporary FPD or FPD in cases of questionable abutment teeth, in aesthetic cases where All Ceram FPD is not feasible. Retention is attained by adhesive cementation to minimally prepared teeth or to conventionally prepared teeth; other options are inlay-onlay bridges or hybrid bridges. Contraindications are: poor hygiene, inability to control humidity, parafunction habits, and more than two pontics. Survival rate of FRC FPD over 5 years is 75%, lower compared to porcelain fused to metal FPD which is 95%. Main reasons for failure are: fracture of framework and delamination of the veneer. Part of the failures is repairable. PMID:21485555
An airborne intensive care facility (fixed wing).
Gilligan, J E; Goon, P; Maughan, G; Griggs, W; Haslam, R; Scholten, A
1996-04-01
A fixed-wing aircraft (Beechcraft KingAir B200 C) fitted as an airborne intensive care facility is described. It completed 2000 missions from 1987-1992 for distances up to 1300 km. Features include: 1. Space for carriage of two stretchers, medical cabin crew of up to five persons and equipment and two-pilot operation if necessary. A third stretcher may be carried in emergencies. 2. Two CARDIOCAP (TM) fixed monitors for ECG, invasive and noninvasive pressures pulse oximetry and end-tidal C02 plus SIEMENS 630(TM)/PROPAQ(TM) compact monitors for the ground transport phase of missions, or the total duration. 3. A medical oxygen reservoir of 4650 litres sufficient for two patients on IPPV with FiO2 = 1.0 for a four-hour trip. The medical suction system is powered from the engine or a vacuum pump. 4. Other medical equipment and drugs in portable packs, for ground transport and resuscitation needs and for replenishment by nursing staff at the parent hospitals. 5. Stretchers compatible with helicopter and road ambulance vehicles used. 6. A stretcher loading device energized from the aircraft, operating through a wide (cargo) door. 7. Provision of 24Ov AC (alternating current) and 28v DC (direct current) electrical energy. 8. Pressurization and climate control. 9. Satisfactory aviation performance for conditions encountered, with single-pilot operation. PMID:9133201
Fixed Drug Eruption due to Achiote Dye
Tattersall, Ian; Reddy, Bobby Y.
2016-01-01
Fixed drug eruption (FDE) is a localized type IV sensitivity reaction to a systemically introduced allergen. It usually occurs as a result of new medication, making identification and avoidance of the trigger medication straightforward; however, in a rare subset of cases no pharmacological source is identified. In such cases, the causative agent is often a food or food additive. In this report we describe a case of a FDE in a 12-year-old girl recently immigrated to the United States from Ecuador who had no medication exposure over the course of her illness. Through an exhaustive patient history and literature review, we were able to hypothesize that her presentation was caused by a dietary change of the natural achiote dye used in the preparation of yellow rice to a locally available commercial dye mix containing tartrazine, or Yellow 5, which has previously been implicated in both systemic hypersensitivity reactions and specifically in FDE. This report adds to the small body of available literature on non-pharmacological fixed hypersensitivity eruptions and illustrates an effective approach to the management of such a presentation when history is not immediately revealing. PMID:26933409
Dark Forces Searches in Fixed Target Experiments
NASA Astrophysics Data System (ADS)
Battaglieri, M.
2014-12-01
Searches for physics Beyond the Standard Model (BSM) can be carried out with precise and GeV-energy-range experiments. In many string theories, a Hidden Sector, decoupled to the SM, foresees the existence of a new massive boson, the A‧ or heavy photon, that weakly couples to the electromagnetic current. A new particle with mass in the range of 1 MeV - 1 GeV could explain many astro-particle observations (e.g. positron excess seen by PAMELA and AMS experiments) and some anomalies not yet fully understood (e.g. muon g - 2 factor). The search for A‧ has motivated intense experimental activities in almost every accelerator facility using different techniques: colliding beam, fixed target experiments, meson rare decays. Jefferson Lab, a world-leading nuclear physics laboratory, is planning a set of fixed target experiments aiming to discover the A‧ or set new limits in its mass and coupling, with an unprecedented sensitivity and reach capability. In this contribution, after reviewing the physics case and some experimental evidences, I will report on the program of measurements planned at Jefferson Lab for the next years.
Fixed Drug Eruption due to Achiote Dye.
Tattersall, Ian; Reddy, Bobby Y
2016-01-01
Fixed drug eruption (FDE) is a localized type IV sensitivity reaction to a systemically introduced allergen. It usually occurs as a result of new medication, making identification and avoidance of the trigger medication straightforward; however, in a rare subset of cases no pharmacological source is identified. In such cases, the causative agent is often a food or food additive. In this report we describe a case of a FDE in a 12-year-old girl recently immigrated to the United States from Ecuador who had no medication exposure over the course of her illness. Through an exhaustive patient history and literature review, we were able to hypothesize that her presentation was caused by a dietary change of the natural achiote dye used in the preparation of yellow rice to a locally available commercial dye mix containing tartrazine, or Yellow 5, which has previously been implicated in both systemic hypersensitivity reactions and specifically in FDE. This report adds to the small body of available literature on non-pharmacological fixed hypersensitivity eruptions and illustrates an effective approach to the management of such a presentation when history is not immediately revealing. PMID:26933409
Action-Sentence Compatibility: The Role of Action Effects and Timing
Diefenbach, Christiane; Rieger, Martina; Massen, Cristina; Prinz, Wolfgang
2013-01-01
Research on embodied approaches to language comprehension suggests that we understand linguistic descriptions of actions by mentally simulating these actions. Evidence is provided by the action-sentence compatibility effect (ACE) which shows that sensibility judgments for sentences are faster when the direction of the described action matches the response direction. In two experiments, we investigated whether the ACE relies on actions or on intended action effects. Participants gave sensibility judgments of auditorily presented sentences by producing an action effect on a screen at a location near the body or far from the body. These action effects were achieved by pressing a response button that was located in either the same spatial direction as the action effect, or in the opposite direction. We used a go/no-go task in which the direction of the to-be-produced action effect was either cued at the onset of each sentence (Experiment 1) or at different points in time before and after sentence onset (Experiment 2). Overall, results showed a relationship between the direction of the described action and the direction of the action effect. Furthermore, Experiment 2 indicated that depending on the timing between cue presentation and sentence onset, participants responded either faster when the direction of the described action matched the direction of the action effect (positive ACE), or slower (negative ACE). These results provide evidence that the comprehension of action sentences involves the activation of representations of action effects. Concurrently activated representations in sentence comprehension and action planning can lead to both priming and interference, which is discussed in the context of the theory of event coding. PMID:23734134
Comparison of Earth-fixed and Sun-fixed regional VTEC modeling strategies using GPS observations
NASA Astrophysics Data System (ADS)
Nohutcu, Metin; Onur Karslioglu, Mahmut; Schmidt, Michael
2010-05-01
Modeling of the ionosphere has been a highly interesting subject within the scientific community due to its effects on the propagation of electromagnetic waves. Numerous modeling studies have been proposed depending on several reference systems. The ionosphere is relatively stable in a Sun-fixed system as the Sun is the main source for its ionization. Therefore, the ionosphere is often modeled in a Sun-fixed reference frame where it can be assumed as static for a certain modeling period. On the other hand, the ionosphere is highly variable in an Earth-fixed reference frame due to the diurnal motion of the Earth. Thus, the models in an Earth-fixed frame should either consider the time dependency or be used instantaneously, i.e. epoch-specific. In this study Vertical Total Electron Content (VTEC) of the ionosphere, which is obtained from the observations of ground based Global Positioning System (GPS) receivers, is modeled with three approaches: 3D (three dimensional) B-spline model in an Earth-fixed reference frame depending on geodetic latitude, geodetic longitude and time and 2D B-spline and spherical harmonic models in a Sun-fixed frame depending on geodetic latitude and Sun-fixed longitude. For all approaches, VTEC is split into two as a reference and a correction term. The reference is computed from low level solutions of the relevant methods while the correction term is obtained with higher level solutions. The parameters for the corresponding linear systems of equations, i.e. unknown model coefficients and differential code biases (DCB) of the receivers, are calculated with least squares estimation. Tikhonov regularization is employed to stabilize the ill-conditioned problems in parameter estimation stage. The models are applied to a real data set which is obtained from ground based GPS receivers over Europe. Carrier phase observations are used to reduce the noise level of pseudorange measurements. Results indicate that B-spline models give more successful results for regional VTEC modeling. Especially, 3-D B-spline solutions represent the temporal change in the ionosphere more successfully than 2-D solutions. On the other hand, it is observed that the length of the modeling period has considerable effect on the results of Sun-fixed VTEC models, especially for the periods of high ionospheric activity. Keywords: Ionosphere Modeling, GPS, B-splines, Spherical Harmonics
NASA Astrophysics Data System (ADS)
Semenov, Alexander; Babikov, Dmitri
2013-11-01
We formulated the mixed quantum/classical theory for rotationally and vibrationally inelastic scattering process in the diatomic molecule + atom system. Two versions of theory are presented, first in the space-fixed and second in the body-fixed reference frame. First version is easy to derive and the resultant equations of motion are transparent, but the state-to-state transition matrix is complex-valued and dense. Such calculations may be computationally demanding for heavier molecules and/or higher temperatures, when the number of accessible channels becomes large. In contrast, the second version of theory requires some tedious derivations and the final equations of motion are rather complicated (not particularly intuitive). However, the state-to-state transitions are driven by real-valued sparse matrixes of much smaller size. Thus, this formulation is the method of choice from the computational point of view, while the space-fixed formulation can serve as a test of the body-fixed equations of motion, and the code. Rigorous numerical tests were carried out for a model system to ensure that all equations, matrixes, and computer codes in both formulations are correct.
Semenov, Alexander; Babikov, Dmitri
2013-11-01
We formulated the mixed quantum/classical theory for rotationally and vibrationally inelastic scattering process in the diatomic molecule + atom system. Two versions of theory are presented, first in the space-fixed and second in the body-fixed reference frame. First version is easy to derive and the resultant equations of motion are transparent, but the state-to-state transition matrix is complex-valued and dense. Such calculations may be computationally demanding for heavier molecules and/or higher temperatures, when the number of accessible channels becomes large. In contrast, the second version of theory requires some tedious derivations and the final equations of motion are rather complicated (not particularly intuitive). However, the state-to-state transitions are driven by real-valued sparse matrixes of much smaller size. Thus, this formulation is the method of choice from the computational point of view, while the space-fixed formulation can serve as a test of the body-fixed equations of motion, and the code. Rigorous numerical tests were carried out for a model system to ensure that all equations, matrixes, and computer codes in both formulations are correct. PMID:24206288
Semenov, Alexander; Babikov, Dmitri
2013-11-07
We formulated the mixed quantum/classical theory for rotationally and vibrationally inelastic scattering process in the diatomic molecule + atom system. Two versions of theory are presented, first in the space-fixed and second in the body-fixed reference frame. First version is easy to derive and the resultant equations of motion are transparent, but the state-to-state transition matrix is complex-valued and dense. Such calculations may be computationally demanding for heavier molecules and/or higher temperatures, when the number of accessible channels becomes large. In contrast, the second version of theory requires some tedious derivations and the final equations of motion are rather complicated (not particularly intuitive). However, the state-to-state transitions are driven by real-valued sparse matrixes of much smaller size. Thus, this formulation is the method of choice from the computational point of view, while the space-fixed formulation can serve as a test of the body-fixed equations of motion, and the code. Rigorous numerical tests were carried out for a model system to ensure that all equations, matrixes, and computer codes in both formulations are correct.
Note on tachyon actions in string theory
Headrick, Matthew
2009-02-15
A number of spacetime fields in string theory (notably the metric, dilaton, bosonic and type 0 bulk closed-string tachyon, and bosonic open-string tachyon) have the following property: whenever the spacetime field configuration factorizes in an appropriate sense, the matter sector of the world-sheet theory factorizes into a tensor product of two decoupled theories. Since the beta functions for such a product theory necessarily also factorize, this property strongly constrains the form of the spacetime action encoding those beta functions. We show that this constraint alone--without needing actually to compute any of the beta functions--is sufficient to fix the form of the two-derivative action for the metric-dilaton system, as well as the potential for the bosonic open-string tachyon. We also show that no action consistent with this constraint exists for the closed-string tachyon coupled to the metric and dilaton.
Action spectrum for phototherapy of psoriasis
Parrish, J.A.; Jaenicke, K.F.
1981-05-01
Using a monochromator the action spectrum for ultraviolet phototherapy of psoriasis was determined for radiation between 254 and 313 nm and compared to the action spectrum for erythema of uninvolved adjacent skin. Daily exposures of different doses of 254, 280, 290, 296, 300, 304 and 313 nm radiation were observed. Wavelengths of 254, 280, 290 nm were erythemogenic but not therapeutic even at 10 to 50 times the minimal erythema dose. At the other wavelengths studied, the 2 action spectra were similar. In general, fixed daily doses cleared at lower cumulative dose than did incrementally increased daily doses. The small number of suberythemogenic exposure doses required suggests that monochromatic radiation may have advantages over broadband sources.
Point-to-Point Multicast Communications Protocol
NASA Technical Reports Server (NTRS)
Byrd, Gregory T.; Nakano, Russell; Delagi, Bruce A.
1987-01-01
This paper describes a protocol to support point-to-point interprocessor communications with multicast. Dynamic, cut-through routing with local flow control is used to provide a high-throughput, low-latency communications path between processors. In addition multicast transmissions are available, in which copies of a packet are sent to multiple destinations using common resources as much as possible. Special packet terminators and selective buffering are introduced to avoid a deadlock during multicasts. A simulated implementation of the protocol is also described.
Sun, J.; Zhang, J. T.; Ping, Q.
2013-09-11
The temperature primary standard over the range from the melting point of gallium to the freezing point of silver in National institute of Metrology (NIM), China, was established in the early 1990s. The performance of all of fixed-point furnaces degraded and needs to be updated due to many years of use. Nowadays, the satisfactory fixed point materials can be available with the development of the modern purification techniques. NIM plans to use a group of three cells for each defining fixed point temperature. In this way the eventual drift of individual cells can be evidenced by periodic intercomparison and this will increase the reliability in disseminating the ITS-90 in China. This article describes the recent improvements in realization of ITS-90 over temperature range from the melting point of gallium to the freezing point of silver at NIM. Taking advantages of the technological advances in the design and manufacture of furnaces, the new three-zone furnaces and the open-type fixed points were developed from the freezing point of indium to the freezing point of silver, and a furnace with the three-zone semiconductor cooling was designed to automatically realize the melting point of gallium. The reproducibility of the new melting point of gallium and the new open-type freezing points of In, Sn, Zn. Al and Ag is improved, especially the freezing points of Al and Ag with the reproducibility of 0.2mK and 0.5mK respectively. The expanded uncertainty in the realization of these defining fixed point temperatures is 0.34mK, 0.44mK, 0.54mK, 0.60mK, 1.30mK and 1.88mK respectively.
NASA Astrophysics Data System (ADS)
Sun, J.; Zhang, J. T.; Ping, Q.
2013-09-01
The temperature primary standard over the range from the melting point of gallium to the freezing point of silver in National institute of Metrology (NIM), China, was established in the early 1990s. The performance of all of fixed-point furnaces degraded and needs to be updated due to many years of use. Nowadays, the satisfactory fixed point materials can be available with the development of the modern purification techniques. NIM plans to use a group of three cells for each defining fixed point temperature. In this way the eventual drift of individual cells can be evidenced by periodic intercomparison and this will increase the reliability in disseminating the ITS-90 in China. This article describes the recent improvements in realization of ITS-90 over temperature range from the melting point of gallium to the freezing point of silver at NIM. Taking advantages of the technological advances in the design and manufacture of furnaces, the new three-zone furnaces and the open-type fixed points were developed from the freezing point of indium to the freezing point of silver, and a furnace with the three-zone semiconductor cooling was designed to automatically realize the melting point of gallium. The reproducibility of the new melting point of gallium and the new open-type freezing points of In, Sn, Zn. Al and Ag is improved, especially the freezing points of Al and Ag with the reproducibility of 0.2mK and 0.5mK respectively. The expanded uncertainty in the realization of these defining fixed point temperatures is 0.34mK, 0.44mK, 0.54mK, 0.60mK, 1.30mK and 1.88mK respectively.
33 CFR 118.65 - Lights on fixed bridges.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Lights on fixed bridges. 118.65 Section 118.65 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.65 Lights on fixed bridges. (a) Each fixed bridge span over a...
33 CFR 118.65 - Lights on fixed bridges.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Lights on fixed bridges. 118.65 Section 118.65 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.65 Lights on fixed bridges. (a) Each fixed bridge span over a...
33 CFR 118.65 - Lights on fixed bridges.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Lights on fixed bridges. 118.65 Section 118.65 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.65 Lights on fixed bridges. (a) Each fixed bridge span over a...
33 CFR 118.65 - Lights on fixed bridges.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Lights on fixed bridges. 118.65 Section 118.65 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.65 Lights on fixed bridges. (a) Each fixed bridge span over a...
33 CFR 118.65 - Lights on fixed bridges.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Lights on fixed bridges. 118.65 Section 118.65 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.65 Lights on fixed bridges. (a) Each fixed bridge span over a...
10 CFR 600.29 - Fixed obligation awards.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 10 Energy 4 2010-01-01 2010-01-01 false Fixed obligation awards. 600.29 Section 600.29 Energy DEPARTMENT OF ENERGY (CONTINUED) ASSISTANCE REGULATIONS FINANCIAL ASSISTANCE RULES General § 600.29 Fixed obligation awards. (a) General. This section contains provisions applicable to the award of financial assistance instruments on a fixed amount...
46 CFR 121.410 - Electronic position fixing devices.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 4 2011-10-01 2011-10-01 false Electronic position fixing devices. 121.410 Section 121... AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Navigation Equipment § 121.410 Electronic position fixing devices. A vessel on an oceans route must be equipped with an electronic position fixing device,...
46 CFR 130.320 - Electronic position-fixing device.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 4 2010-10-01 2010-10-01 false Electronic position-fixing device. 130.320 Section 130... CONTROL, AND MISCELLANEOUS EQUIPMENT AND SYSTEMS Navigational Equipment § 130.320 Electronic position-fixing device. Each vessel must be equipped with an electronic position-fixing device satisfactory...
46 CFR 121.410 - Electronic position fixing devices.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 4 2010-10-01 2010-10-01 false Electronic position fixing devices. 121.410 Section 121... AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Navigation Equipment § 121.410 Electronic position fixing devices. A vessel on an oceans route must be equipped with an electronic position fixing device,...
46 CFR 130.320 - Electronic position-fixing device.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 4 2011-10-01 2011-10-01 false Electronic position-fixing device. 130.320 Section 130... CONTROL, AND MISCELLANEOUS EQUIPMENT AND SYSTEMS Navigational Equipment § 130.320 Electronic position-fixing device. Each vessel must be equipped with an electronic position-fixing device satisfactory...
46 CFR 118.410 - Fixed gas fire extinguishing systems.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 46 Shipping 4 2014-10-01 2014-10-01 false Fixed gas fire extinguishing systems. 118.410 Section... CARRYING MORE THAN 150 PASSENGERS OR WITH OVERNIGHT ACCOMMODATIONS FOR MORE THAN 49 PASSENGERS FIRE PROTECTION EQUIPMENT Fixed Fire Extinguishing and Detecting Systems § 118.410 Fixed gas fire...
46 CFR 118.410 - Fixed gas fire extinguishing systems.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 46 Shipping 4 2012-10-01 2012-10-01 false Fixed gas fire extinguishing systems. 118.410 Section... CARRYING MORE THAN 150 PASSENGERS OR WITH OVERNIGHT ACCOMMODATIONS FOR MORE THAN 49 PASSENGERS FIRE PROTECTION EQUIPMENT Fixed Fire Extinguishing and Detecting Systems § 118.410 Fixed gas fire...
29 CFR 1910.160 - Fixed extinguishing systems, general.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 29 Labor 5 2012-07-01 2012-07-01 false Fixed extinguishing systems, general. 1910.160 Section 1910.160 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR OCCUPATIONAL SAFETY AND HEALTH STANDARDS Fire Protection Fixed Fire Suppression Equipment § 1910.160 Fixed extinguishing...
47 CFR 101.125 - Temporary fixed antenna height restrictions.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 47 Telecommunication 5 2010-10-01 2010-10-01 false Temporary fixed antenna height restrictions... SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Technical Standards § 101.125 Temporary fixed antenna height restrictions. The overall antenna structure heights employed by mobile stations in the...
47 CFR 101.125 - Temporary fixed antenna height restrictions.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 47 Telecommunication 5 2011-10-01 2011-10-01 false Temporary fixed antenna height restrictions... SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Technical Standards § 101.125 Temporary fixed antenna height restrictions. The overall antenna structure heights employed by mobile stations in the...
48 CFR 52.243-1 - Changes-Fixed-Price.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Changes-Fixed-Price. 52....243-1 Changes—Fixed-Price. As prescribed in 43.205(e), insert the following clause: Changes—Fixed-Price (AUG 1987) (a) The Contracting Officer may at any time, by written order, and without notice...
47 CFR 25.277 - Temporary fixed earth station operations.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 47 Telecommunication 2 2013-10-01 2013-10-01 false Temporary fixed earth station operations. 25... SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.277 Temporary fixed earth station operations. (a) When an earth station in the Fixed-Satellite Service is to remain at a single location for...
47 CFR 25.277 - Temporary fixed earth station operations.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 47 Telecommunication 2 2012-10-01 2012-10-01 false Temporary fixed earth station operations. 25... SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.277 Temporary fixed earth station operations. (a) When an earth station in the Fixed-Satellite Service is to remain at a single location for...
47 CFR 25.277 - Temporary fixed earth station operations.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 47 Telecommunication 2 2014-10-01 2014-10-01 false Temporary fixed earth station operations. 25... SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.277 Temporary fixed earth station operations. (a) When an earth station in the Fixed-Satellite Service is to remain at a single location for...
12 CFR 701.36 - FCU ownership of fixed assets.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 12 Banks and Banking 7 2012-01-01 2012-01-01 false FCU ownership of fixed assets. 701.36 Section... ORGANIZATION AND OPERATION OF FEDERAL CREDIT UNIONS § 701.36 FCU ownership of fixed assets. (a) Investment in Fixed Assets. (1) No Federal credit union with $1,000,000 or more in assets may invest in any...
12 CFR 701.36 - FCU ownership of fixed assets.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 12 Banks and Banking 6 2011-01-01 2011-01-01 false FCU ownership of fixed assets. 701.36 Section 701.36 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS ORGANIZATION AND OPERATION OF FEDERAL CREDIT UNIONS § 701.36 FCU ownership of fixed assets. (a) Investment in Fixed Assets. (1) No Federal credit...
12 CFR 701.36 - FCU ownership of fixed assets.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 12 Banks and Banking 6 2010-01-01 2010-01-01 false FCU ownership of fixed assets. 701.36 Section... ORGANIZATION AND OPERATION OF FEDERAL CREDIT UNIONS § 701.36 FCU ownership of fixed assets. (a) Investment in Fixed Assets. (1) No Federal credit union with $1,000,000 or more in assets may invest in any...
12 CFR 701.36 - FCU ownership of fixed assets.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 12 Banks and Banking 7 2013-01-01 2013-01-01 false FCU ownership of fixed assets. 701.36 Section... ORGANIZATION AND OPERATION OF FEDERAL CREDIT UNIONS § 701.36 FCU ownership of fixed assets. (a) Investment in Fixed Assets. (1) No Federal credit union with $1,000,000 or more in assets may invest in any...
50 CFR 660.372 - Fixed gear sablefish fishery management.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Fixed gear sablefish fishery management... West Coast Groundfish Fisheries § 660.372 Fixed gear sablefish fishery management. This section applies to the primary season for the fixed gear limited entry sablefish fishery north of 36° N. lat.,...
47 CFR 80.387 - Frequencies for Alaska fixed stations.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 47 Telecommunication 5 2011-10-01 2011-10-01 false Frequencies for Alaska fixed stations. 80.387... SERVICES STATIONS IN THE MARITIME SERVICES Frequencies Alaska Fixed Stations § 80.387 Frequencies for Alaska fixed stations. (a) The carrier frequencies listed in (b) of this section are assignable for...
47 CFR 80.387 - Frequencies for Alaska fixed stations.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 47 Telecommunication 5 2014-10-01 2014-10-01 false Frequencies for Alaska fixed stations. 80.387... SERVICES STATIONS IN THE MARITIME SERVICES Frequencies Alaska Fixed Stations § 80.387 Frequencies for Alaska fixed stations. (a) The carrier frequencies listed in (b) of this section are assignable for...
47 CFR 80.387 - Frequencies for Alaska fixed stations.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 47 Telecommunication 5 2013-10-01 2013-10-01 false Frequencies for Alaska fixed stations. 80.387... SERVICES STATIONS IN THE MARITIME SERVICES Frequencies Alaska Fixed Stations § 80.387 Frequencies for Alaska fixed stations. (a) The carrier frequencies listed in (b) of this section are assignable for...
47 CFR 80.387 - Frequencies for Alaska fixed stations.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 47 Telecommunication 5 2010-10-01 2010-10-01 false Frequencies for Alaska fixed stations. 80.387... SERVICES STATIONS IN THE MARITIME SERVICES Frequencies Alaska Fixed Stations § 80.387 Frequencies for Alaska fixed stations. (a) The carrier frequencies listed in (b) of this section are assignable for...