Many-core graph analytics using accelerated sparse linear algebra routines

NASA Astrophysics Data System (ADS)

Kozacik, Stephen; Paolini, Aaron L.; Fox, Paul; Kelmelis, Eric

2016-05-01

Graph analytics is a key component in identifying emerging trends and threats in many real-world applications. Largescale graph analytics frameworks provide a convenient and highly-scalable platform for developing algorithms to analyze large datasets. Although conceptually scalable, these techniques exhibit poor performance on modern computational hardware. Another model of graph computation has emerged that promises improved performance and scalability by using abstract linear algebra operations as the basis for graph analysis as laid out by the GraphBLAS standard. By using sparse linear algebra as the basis, existing highly efficient algorithms can be adapted to perform computations on the graph. This approach, however, is often less intuitive to graph analytics experts, who are accustomed to vertex-centric APIs such as Giraph, GraphX, and Tinkerpop. We are developing an implementation of the high-level operations supported by these APIs in terms of linear algebra operations. This implementation is be backed by many-core implementations of the fundamental GraphBLAS operations required, and offers the advantages of both the intuitive programming model of a vertex-centric API and the performance of a sparse linear algebra implementation. This technology can reduce the number of nodes required, as well as the run-time for a graph analysis problem, enabling customers to perform more complex analysis with less hardware at lower cost. All of this can be accomplished without the requirement for the customer to make any changes to their analytics code, thanks to the compatibility with existing graph APIs.

Highly Productive Application Development with ViennaCL for Accelerators

NASA Astrophysics Data System (ADS)

Rupp, K.; Weinbub, J.; Rudolf, F.

2012-12-01

The use of graphics processing units (GPUs) for the acceleration of general purpose computations has become very attractive over the last years, and accelerators based on many integrated CPU cores are about to hit the market. However, there are discussions about the benefit of GPU computing when comparing the reduction of execution times with the increased development effort [1]. To counter these concerns, our open-source linear algebra library ViennaCL [2,3] uses modern programming techniques such as generic programming in order to provide a convenient access layer for accelerator and GPU computing. Other GPU-accelerated libraries are primarily tuned for performance, but less tailored to productivity and portability: MAGMA [4] provides dense linear algebra operations via a LAPACK-comparable interface, but no dedicated matrix and vector types. Cusp [5] is closest in functionality to ViennaCL for sparse matrices, but is based on CUDA and thus restricted to devices from NVIDIA. However, no convenience layer for dense linear algebra is provided with Cusp. ViennaCL is written in C++ and uses OpenCL to access the resources of accelerators, GPUs and multi-core CPUs in a unified way. On the one hand, the library provides iterative solvers from the family of Krylov methods, including various preconditioners, for the solution of linear systems typically obtained from the discretization of partial differential equations. On the other hand, dense linear algebra operations are supported, including algorithms such as QR factorization and singular value decomposition. The user application interface of ViennaCL is compatible to uBLAS [6], which is part of the peer-reviewed Boost C++ libraries [7]. This allows to port existing applications based on uBLAS with a minimum of effort to ViennaCL. Conversely, the interface compatibility allows to use the iterative solvers from ViennaCL with uBLAS types directly, thus enabling code reuse beyond CPU-GPU boundaries. Out-of-the-box support for types from the Eigen library [8] and MTL 4 [9] are provided as well, enabling a seamless transition from single-core CPU to GPU and multi-core CPU computations. Case studies from the numerical solution of PDEs are given and isolated performance benchmarks are discussed. Also, pitfalls in scientific computing with GPUs and accelerators are addressed, allowing for a first evaluation of whether these novel devices can be mapped well to certain applications. References: [1] R. Bordawekar et al., Technical Report, IBM, 2010 [2] ViennaCL library. Online: http://viennacl.sourceforge.net/ [3] K. Rupp et al., GPUScA, 2010 [4] MAGMA library. Online: http://icl.cs.utk.edu/magma/ [5] Cusp library. Online: http://code.google.com/p/cusp-library/ [6] uBLAS library. Online: http://www.boost.org/libs/numeric/ublas/ [7] Boost C++ Libraries. Online: http://www.boost.org/ [8] Eigen library. Online: http://eigen.tuxfamily.org/ [9] MTL 4 Library. Online: http://www.mtl4.org/

33 CFR 334.670 - Gulf of Mexico south and west of Apalachicola, San Blas, and St. Joseph bays; air-to-air firing...

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Gulf of Mexico south and west of Apalachicola, San Blas, and St. Joseph bays; air-to-air firing practice range, Tyndall Air Force Base, Fla. 334... Apalachicola, San Blas, and St. Joseph bays; air-to-air firing practice range, Tyndall Air Force Base, Fla. (a...

High-Speed, Low-Cost Workstation for Computation-Intensive Statistics. Phase 1

DTIC Science & Technology

1990-06-20

routine implementation and performance. 5 The two compiled versions given in the table were coded in an attempt to obtain an optimized compiled version...level statistics and linear algebra routines (BSAS and BLAS) that have been prototyped in this study. For each routine, both the C code ( Turbo C...OISTRIBUTION /AVAILABILITY STATEMENT 12b. DISTRIBUTION CODE Unlimited distribution 13. ABSTRACT (Maximum 200 words) High-performance and low-cost

Replicated computational results (RCR) report for "BLIS: A framework for rapidly instantiating BLAS functionality"

DOE PAGES

Willenbring, James Michael

2015-06-03

“BLIS: A Framework for Rapidly Instantiating BLAS Functionality” includes single-platform BLIS performance results for both level-2 and level-3 operations that is competitive with OpenBLAS, ATLAS, and Intel MKL. A detailed description of the configuration used to generate the performance results was provided to the reviewer by the authors. All the software components used in the comparison were reinstalled and new performance results were generated and compared to the original results. After completing this process, the published results are deemed replicable by the reviewer.

A VLT/MUSE galaxy survey towards QSO Q1410: looking for a WHIM traced by BLAs in inter-cluster filaments

NASA Astrophysics Data System (ADS)

Pessa, Ismael; Tejos, Nicolas; Barrientos, L. Felipe; Werk, Jessica; Bielby, Richard; Padilla, Nelson; Morris, Simon L.; Prochaska, J. Xavier; Lopez, Sebastian; Hummels, Cameron

2018-07-01

Cosmological simulations predict that a significant fraction of the low-z baryon budget resides in large-scale filaments in the form of a diffuse plasma at temperatures T ˜ 105 - 107 K. However, direct observation of this so-called warm-hot intergalactic medium (WHIM) has been elusive. In the Λcold dark matter paradigm, galaxy clusters correspond to the nodes of the cosmic web at the intersection of several large-scale filamentary threads. In previous work, we used HST/COS data to conduct the first survey of broad H I Lyα absorbers (BLAs) potentially produced by WHIM in inter-cluster filaments. We targeted a single QSO, namely Q1410, whose sightline intersects seven independent inter-cluster axes at impact parameters <3 Mpc (comoving), and found a tentative excess of a factor of ˜4 with respect to the field. Here, we further investigate the origin of these BLAs by performing a blind galaxy survey within the Q1410 field using VLT/MUSE. We identified 77 sources and obtained the redshifts for 52 of them. Out of the total sample of seven BLAs in inter-cluster axes, we found three without any galaxy counterpart to stringent luminosity limits (˜4 × 108 L⊙ ˜0.01 L*), providing further evidence that these BLAs may represent genuine WHIM detections. We combined this sample with other suitable BLAs from the literature and inferred the corresponding baryon mean density for these filaments in the range Ω ^fil_bar= 0.02-0.04. Our rough estimates are consistent with the predictions from numerical simulations but still subject to large systematic uncertainties, mostly from the adopted geometry, ionization corrections, and density profile.

Acceleration of GPU-based Krylov solvers via data transfer reduction

DOE PAGES

Anzt, Hartwig; Tomov, Stanimire; Luszczek, Piotr; ...

2015-04-08

Krylov subspace iterative solvers are often the method of choice when solving large sparse linear systems. At the same time, hardware accelerators such as graphics processing units continue to offer significant floating point performance gains for matrix and vector computations through easy-to-use libraries of computational kernels. However, as these libraries are usually composed of a well optimized but limited set of linear algebra operations, applications that use them often fail to reduce certain data communications, and hence fail to leverage the full potential of the accelerator. In this study, we target the acceleration of Krylov subspace iterative methods for graphicsmore » processing units, and in particular the Biconjugate Gradient Stabilized solver that significant improvement can be achieved by reformulating the method to reduce data-communications through application-specific kernels instead of using the generic BLAS kernels, e.g. as provided by NVIDIA’s cuBLAS library, and by designing a graphics processing unit specific sparse matrix-vector product kernel that is able to more efficiently use the graphics processing unit’s computing power. Furthermore, we derive a model estimating the performance improvement, and use experimental data to validate the expected runtime savings. Finally, considering that the derived implementation achieves significantly higher performance, we assert that similar optimizations addressing algorithm structure, as well as sparse matrix-vector, are crucial for the subsequent development of high-performance graphics processing units accelerated Krylov subspace iterative methods.« less

33 CFR 80.805 - Rock Island, FL to Cape San Blas, FL.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Rock Island, FL to Cape San Blas, FL. 80.805 Section 80.805 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Eighth District § 80.805 Rock Island, FL...

33 CFR 80.805 - Rock Island, FL to Cape San Blas, FL.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Rock Island, FL to Cape San Blas, FL. 80.805 Section 80.805 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Eighth District § 80.805 Rock Island, FL...

33 CFR 80.805 - Rock Island, FL to Cape San Blas, FL.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Rock Island, FL to Cape San Blas, FL. 80.805 Section 80.805 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Eighth District § 80.805 Rock Island, FL...

33 CFR 80.805 - Rock Island, FL to Cape San Blas, FL.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Rock Island, FL to Cape San Blas, FL. 80.805 Section 80.805 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Eighth District § 80.805 Rock Island, FL...

33 CFR 80.805 - Rock Island, FL to Cape San Blas, FL.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Rock Island, FL to Cape San Blas, FL. 80.805 Section 80.805 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Eighth District § 80.805 Rock Island, FL...

A parallel solver for huge dense linear systems

NASA Astrophysics Data System (ADS)

Badia, J. M.; Movilla, J. L.; Climente, J. I.; Castillo, M.; Marqués, M.; Mayo, R.; Quintana-Ortí, E. S.; Planelles, J.

2011-11-01

HDSS (Huge Dense Linear System Solver) is a Fortran Application Programming Interface (API) to facilitate the parallel solution of very large dense systems to scientists and engineers. The API makes use of parallelism to yield an efficient solution of the systems on a wide range of parallel platforms, from clusters of processors to massively parallel multiprocessors. It exploits out-of-core strategies to leverage the secondary memory in order to solve huge linear systems O(100.000). The API is based on the parallel linear algebra library PLAPACK, and on its Out-Of-Core (OOC) extension POOCLAPACK. Both PLAPACK and POOCLAPACK use the Message Passing Interface (MPI) as the communication layer and BLAS to perform the local matrix operations. The API provides a friendly interface to the users, hiding almost all the technical aspects related to the parallel execution of the code and the use of the secondary memory to solve the systems. In particular, the API can automatically select the best way to store and solve the systems, depending of the dimension of the system, the number of processes and the main memory of the platform. Experimental results on several parallel platforms report high performance, reaching more than 1 TFLOP with 64 cores to solve a system with more than 200 000 equations and more than 10 000 right-hand side vectors. New version program summaryProgram title: Huge Dense System Solver (HDSS) Catalogue identifier: AEHU_v1_1 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEHU_v1_1.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 87 062 No. of bytes in distributed program, including test data, etc.: 1 069 110 Distribution format: tar.gz Programming language: Fortran90, C Computer: Parallel architectures: multiprocessors, computer clusters Operating system: Linux/Unix Has the code been vectorized or parallelized?: Yes, includes MPI primitives. RAM: Tested for up to 190 GB Classification: 6.5 External routines: MPI ( http://www.mpi-forum.org/), BLAS ( http://www.netlib.org/blas/), PLAPACK ( http://www.cs.utexas.edu/~plapack/), POOCLAPACK ( ftp://ftp.cs.utexas.edu/pub/rvdg/PLAPACK/pooclapack.ps) (code for PLAPACK and POOCLAPACK is included in the distribution). Catalogue identifier of previous version: AEHU_v1_0 Journal reference of previous version: Comput. Phys. Comm. 182 (2011) 533 Does the new version supersede the previous version?: Yes Nature of problem: Huge scale dense systems of linear equations, Ax=B, beyond standard LAPACK capabilities. Solution method: The linear systems are solved by means of parallelized routines based on the LU factorization, using efficient secondary storage algorithms when the available main memory is insufficient. Reasons for new version: In many applications we need to guarantee a high accuracy in the solution of very large linear systems and we can do it by using double-precision arithmetic. Summary of revisions: Version 1.1 Can be used to solve linear systems using double-precision arithmetic. New version of the initialization routine. The user can choose the kind of arithmetic and the values of several parameters of the environment. Running time: About 5 hours to solve a system with more than 200 000 equations and more than 10 000 right-hand side vectors using double-precision arithmetic on an eight-node commodity cluster with a total of 64 Intel cores.

CUDAICA: GPU Optimization of Infomax-ICA EEG Analysis

PubMed Central

Raimondo, Federico; Kamienkowski, Juan E.; Sigman, Mariano; Fernandez Slezak, Diego

2012-01-01

In recent years, Independent Component Analysis (ICA) has become a standard to identify relevant dimensions of the data in neuroscience. ICA is a very reliable method to analyze data but it is, computationally, very costly. The use of ICA for online analysis of the data, used in brain computing interfaces, results are almost completely prohibitive. We show an increase with almost no cost (a rapid video card) of speed of ICA by about 25 fold. The EEG data, which is a repetition of many independent signals in multiple channels, is very suitable for processing using the vector processors included in the graphical units. We profiled the implementation of this algorithm and detected two main types of operations responsible of the processing bottleneck and taking almost 80% of computing time: vector-matrix and matrix-matrix multiplications. By replacing function calls to basic linear algebra functions to the standard CUBLAS routines provided by GPU manufacturers, it does not increase performance due to CUDA kernel launch overhead. Instead, we developed a GPU-based solution that, comparing with the original BLAS and CUBLAS versions, obtains a 25x increase of performance for the ICA calculation. PMID:22811699

A Retrospective Evaluation of the Use of Mass Spectrometry in FDA Biologics License Applications

NASA Astrophysics Data System (ADS)

Rogstad, Sarah; Faustino, Anneliese; Ruth, Ashley; Keire, David; Boyne, Michael; Park, Jun

2017-05-01

The characterization sections of biologics license applications (BLAs) approved by the United States Food and Drug Administration (FDA) between 2000 and 2015 were investigated to examine the extent of the use of mass spectrometry. Mass spectrometry was found to be integral to the characterization of these biotherapeutics. Of the 80 electronically submitted monoclonal antibody and protein biotherapeutic BLAs included in this study, 79 were found to use mass spectrometric workflows for protein or impurity characterization. To further examine how MS is being used in successful BLAs, the applications were filtered based on the type and number of quality attributes characterized, the mass spectrometric workflows used (peptide mapping, intact mass analysis, and cleaved glycan analysis), the methods used to introduce the proteins into the gas phase (ESI, MALDI, or LC-ESI), and the specific types of instrumentation used. Analyses were conducted over a time course based on the FDA BLA approval to determine if any trends in utilization could be observed over time. Additionally, the different classes of protein-based biotherapeutics among the approved BLAs were clustered to determine if any trends could be attributed to the specific type of biotherapeutic.

Does flavanol intake influence mortality from nitric oxide-dependent processes? Ischemic heart disease, stroke, diabetes mellitus, and cancer in Panama.

PubMed

Bayard, Vicente; Chamorro, Fermina; Motta, Jorge; Hollenberg, Norman K

2007-01-27

Substantial data suggest that flavonoid-rich food could help prevent cardiovascular disease and cancer. Cocoa is the richest source of flavonoids, but current processing reduces the content substantially. The Kuna living in the San Blas drink a flavanol-rich cocoa as their main beverage, contributing more than 900 mg/day and thus probably have the most flavonoid-rich diet of any population. We used diagnosis on death certificates to compare cause-specific death rates from year 2000 to 2004 in mainland and the San Blas islands where only Kuna live. Our hypothesis was that if the high flavanoid intake and consequent nitric oxide system activation were important the result would be a reduction in the frequency of ischemic heart disease, stroke, diabetes mellitus, and cancer--all nitric oxide sensitive processes. There were 77,375 deaths in mainland Panama and 558 deaths in the San Blas. In mainland Panama, as anticipated, cardiovascular disease was the leading cause of death (83.4 +/- 0.70 age adjusted deaths/100,000) and cancer was second (68.4 +/- 1.6). In contrast, the rate of CVD and cancer among island-dwelling Kuna was much lower (9.2 +/- 3.1) and (4.4 +/- 4.4) respectively. Similarly deaths due to diabetes mellitus were much more common in the mainland (24.1 +/- 0.74) than in the San Blas (6.6 +/- 1.94). This comparatively lower risk among Kuna in the San Blas from the most common causes of morbidity and mortality in much of the world, possibly reflects a very high flavanol intake and sustained nitric oxide synthesis activation. However, there are many risk factors and an observational study cannot provide definitive evidence.

33 CFR 334.670 - Gulf of Mexico south and west of Apalachicola, San Blas, and St. Joseph bays; air-to-air firing...

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Gulf of Mexico south and west of Apalachicola, San Blas, and St. Joseph bays; air-to-air firing practice range, Tyndall Air Force Base, Fla. 334..., DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.670 Gulf of Mexico south and west of...

33 CFR 334.670 - Gulf of Mexico south and west of Apalachicola, San Blas, and St. Joseph bays; air-to-air firing...

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Gulf of Mexico south and west of Apalachicola, San Blas, and St. Joseph bays; air-to-air firing practice range, Tyndall Air Force Base, Fla. 334..., DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.670 Gulf of Mexico south and west of...

33 CFR 334.670 - Gulf of Mexico south and west of Apalachicola, San Blas, and St. Joseph bays; air-to-air firing...

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Gulf of Mexico south and west of Apalachicola, San Blas, and St. Joseph bays; air-to-air firing practice range, Tyndall Air Force Base, Fla. 334..., DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.670 Gulf of Mexico south and west of...

33 CFR 334.670 - Gulf of Mexico south and west of Apalachicola, San Blas, and St. Joseph bays; air-to-air firing...

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Gulf of Mexico south and west of Apalachicola, San Blas, and St. Joseph bays; air-to-air firing practice range, Tyndall Air Force Base, Fla. 334..., DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.670 Gulf of Mexico south and west of...

Participation of Women and Sex Analyses in Late-Phase Clinical Trials of New Molecular Entity Drugs and Biologics Approved by the FDA in 2007–2009

PubMed Central

Poon, Rita; Khanijow, Keshav; Umarjee, Sphoorti; Yu, Monica; Zhang, Lei; Parekh, Ameeta

2013-01-01

Abstract Background Biological sex differences may contribute to differential treatment outcomes for therapeutic products. This study tracks women's participation in late-phase clinical trials (LPCTs), where efficacy and safety of drugs and biologics are evaluated, of new molecular entity (NME) drugs and biologics approved by the U.S. Food and Drug Administration (FDA) in 2007–2009. Furthermore, presentations of sex-based analyses were assessed from the FDA reviews. Methods New drug applications (NDAs) and biologics license applications (BLAs) were accessed from the U.S. FDA database and evaluated for women's participation in LPCTs. Sex-based analyses for efficacy and safety contained in FDA reviews were surveyed. Ratios for women's LPCT participation (PROPORTION OF STUDY SUBJECTS) to their proportion in the disease population were calculated for each approved therapeutic product and grouped into therapeutic categories. Results Sex-specific (n=5) and pediatric (n=3) drug applications were excluded. Women's participation in LPCTs was 39%, 48%, and 42% in NDAs (n=50) and 49%, 62%, and 58% in BLAs (n=11) for 2007, 2008, and 2009, respectively. Sixty-four percent of NDAs and 91% of BLAs had participation to proportion ratios of ≥0.80. Seventy-four percent of NDA reviews and 64% of BLA reviews included safety and efficacy sex analysis. Ninety-six percent of NDA reviews and 100% of BLA reviews included efficacy sex analysis. Conclusion Women's participation in LPCTs averaged 43% for NDAs and 57% for BLAs in 2007–2009 and varied widely by indication. As a comparison, the 2001 U.S. Government Accountability Office (GAO) reported 52% of women's participation for drug clinical trials in1998–2000 and an FDA study reported 45% for BLAs approved from 1995 to 1999. This study showed that sex-analysis of both safety and efficacy in NDA has increased to 74% since the GAO report of 72%, while those for BLAs increased to 64% from 37% reported for therapeutic biologics approved in 1995–1999. Knowledge of disease prevalence and participation in clinical trials provides an understanding of recruitment and retention patterns of patients in these trials. PMID:23768021

Community Reaction to Impulsive Noise. A Final 10-Year Research Summary. Revised.

DTIC Science & Technology

1985-06-01

Research Council (1931). blas nose vens ocurrd a niht.Statle nd rigt , he P. D. Schomer, "Dlast Noise Prediction Volume 1: Data Bases and Com-blas noie...change is mirrored in a later study of chinchillas taught to respond to a change in a frequently repeated sound." These animals were much more likely to...34frustration." Among nonverbal animals in Skinner boxes, After discarding complaints about obscure noise extinction is often accompanied by overt

Acceleration of Linear Finite-Difference Poisson-Boltzmann Methods on Graphics Processing Units.

PubMed

Qi, Ruxi; Botello-Smith, Wesley M; Luo, Ray

2017-07-11

Electrostatic interactions play crucial roles in biophysical processes such as protein folding and molecular recognition. Poisson-Boltzmann equation (PBE)-based models have emerged as widely used in modeling these important processes. Though great efforts have been put into developing efficient PBE numerical models, challenges still remain due to the high dimensionality of typical biomolecular systems. In this study, we implemented and analyzed commonly used linear PBE solvers for the ever-improving graphics processing units (GPU) for biomolecular simulations, including both standard and preconditioned conjugate gradient (CG) solvers with several alternative preconditioners. Our implementation utilizes the standard Nvidia CUDA libraries cuSPARSE, cuBLAS, and CUSP. Extensive tests show that good numerical accuracy can be achieved given that the single precision is often used for numerical applications on GPU platforms. The optimal GPU performance was observed with the Jacobi-preconditioned CG solver, with a significant speedup over standard CG solver on CPU in our diversified test cases. Our analysis further shows that different matrix storage formats also considerably affect the efficiency of different linear PBE solvers on GPU, with the diagonal format best suited for our standard finite-difference linear systems. Further efficiency may be possible with matrix-free operations and integrated grid stencil setup specifically tailored for the banded matrices in PBE-specific linear systems.

FPGA implementation of sparse matrix algorithm for information retrieval

NASA Astrophysics Data System (ADS)

Bojanic, Slobodan; Jevtic, Ruzica; Nieto-Taladriz, Octavio

2005-06-01

Information text data retrieval requires a tremendous amount of processing time because of the size of the data and the complexity of information retrieval algorithms. In this paper the solution to this problem is proposed via hardware supported information retrieval algorithms. Reconfigurable computing may adopt frequent hardware modifications through its tailorable hardware and exploits parallelism for a given application through reconfigurable and flexible hardware units. The degree of the parallelism can be tuned for data. In this work we implemented standard BLAS (basic linear algebra subprogram) sparse matrix algorithm named Compressed Sparse Row (CSR) that is showed to be more efficient in terms of storage space requirement and query-processing timing over the other sparse matrix algorithms for information retrieval application. Although inverted index algorithm is treated as the de facto standard for information retrieval for years, an alternative approach to store the index of text collection in a sparse matrix structure gains more attention. This approach performs query processing using sparse matrix-vector multiplication and due to parallelization achieves a substantial efficiency over the sequential inverted index. The parallel implementations of information retrieval kernel are presented in this work targeting the Virtex II Field Programmable Gate Arrays (FPGAs) board from Xilinx. A recent development in scientific applications is the use of FPGA to achieve high performance results. Computational results are compared to implementations on other platforms. The design achieves a high level of parallelism for the overall function while retaining highly optimised hardware within processing unit.

Applications Performance Under MPL and MPI on NAS IBM SP2

NASA Technical Reports Server (NTRS)

Saini, Subhash; Simon, Horst D.; Lasinski, T. A. (Technical Monitor)

1994-01-01

On July 5, 1994, an IBM Scalable POWER parallel System (IBM SP2) with 64 nodes, was installed at the Numerical Aerodynamic Simulation (NAS) Facility Each node of NAS IBM SP2 is a "wide node" consisting of a RISC 6000/590 workstation module with a clock of 66.5 MHz which can perform four floating point operations per clock with a peak performance of 266 Mflop/s. By the end of 1994, 64 nodes of IBM SP2 will be upgraded to 160 nodes with a peak performance of 42.5 Gflop/s. An overview of the IBM SP2 hardware is presented. The basic understanding of architectural details of RS 6000/590 will help application scientists the porting, optimizing, and tuning of codes from other machines such as the CRAY C90 and the Paragon to the NAS SP2. Optimization techniques such as quad-word loading, effective utilization of two floating point units, and data cache optimization of RS 6000/590 is illustrated, with examples giving performance gains at each optimization step. The conversion of codes using Intel's message passing library NX to codes using native Message Passing Library (MPL) and the Message Passing Interface (NMI) library available on the IBM SP2 is illustrated. In particular, we will present the performance of Fast Fourier Transform (FFT) kernel from NAS Parallel Benchmarks (NPB) under MPL and MPI. We have also optimized some of Fortran BLAS 2 and BLAS 3 routines, e.g., the optimized Fortran DAXPY runs at 175 Mflop/s and optimized Fortran DGEMM runs at 230 Mflop/s per node. The performance of the NPB (Class B) on the IBM SP2 is compared with the CRAY C90, Intel Paragon, TMC CM-5E, and the CRAY T3D.

Spaceport Florida Authority

NASA Technical Reports Server (NTRS)

1991-01-01

The topics are covered in viewgraph form and include the following: objectives; current initiatives; the Space Research Initiative Program; the Cape San Blas Launch Program; and Spaceport Florida Laboratories.

Intensity control in swim training by means of the individual anaerobic threshold.

PubMed

Skorski, Sabrina; Faude, Oliver; Urhausen, Axel; Kindermann, Wilfried; Meyer, Tim

2012-12-01

This study aimed at evaluating the homogeneity of physiological responses during swim training bouts with intensities prescribed by reference to the individual anaerobic threshold (IAT). Eighteen competitive front crawl swimmers (female 5, male 13, 10 long-distance, and 8 short-distance swimmers [LDSs, SDSs], age: 17 ± 1.7 years, training history: 7.0 ± 2.8 years, training volume per week: 35 ± 5.7 km) performed an incremental swimming test to determine the IAT. Within a maximum of 3 weeks, 4 training programs were conducted: 20 × 100-m low-intensity endurance training (EN(low), 97% IAT), 5 × 400-m high-intensity endurance training (EN(high), 101% IAT), 5 × 200 m (IT1, 105% IAT), and 10 × 100 m (IT2, 108% IAT) intensive interval training. Blood lactate concentrations (bLa) were determined during each training session. The results are given as median (25th and 75th percentiles). During EN(low) and EN(high), the mean bLas were 1.8 mmol·L(-1) (1.3/3.0 mmol·L(-1)) and 4.4 mmol·L(-1) (3.9/6.4 mmol·L(-1)). The bLas were higher during both IT programs: IT1, 6.3 mmol·L(-1) (5.6/7.2 mmol·L(-1)); IT2, 5.8 mmol·L(-1) (5.0/6.5 mmol·L(-1)). The bLas of most individuals were close to the median values (±2.4 mmol·L(-1)). However, in each of the training programs, some subjects showed bLa values that were clearly above (3-7 mmol·L(-1) higher). In particular, SDSs reached higher bLas at the same intensity compared with LDSs. It is concluded that intensity prescriptions by means of IAT seem to elicit an expected metabolic response in approximately 85% of swim training sessions. The observed average bLa is in the range of those recommended in the scientific literature.

GPU Linear Algebra Libraries and GPGPU Programming for Accelerating MOPAC Semiempirical Quantum Chemistry Calculations.

PubMed

Maia, Julio Daniel Carvalho; Urquiza Carvalho, Gabriel Aires; Mangueira, Carlos Peixoto; Santana, Sidney Ramos; Cabral, Lucidio Anjos Formiga; Rocha, Gerd B

2012-09-11

In this study, we present some modifications in the semiempirical quantum chemistry MOPAC2009 code that accelerate single-point energy calculations (1SCF) of medium-size (up to 2500 atoms) molecular systems using GPU coprocessors and multithreaded shared-memory CPUs. Our modifications consisted of using a combination of highly optimized linear algebra libraries for both CPU (LAPACK and BLAS from Intel MKL) and GPU (MAGMA and CUBLAS) to hasten time-consuming parts of MOPAC such as the pseudodiagonalization, full diagonalization, and density matrix assembling. We have shown that it is possible to obtain large speedups just by using CPU serial linear algebra libraries in the MOPAC code. As a special case, we show a speedup of up to 14 times for a methanol simulation box containing 2400 atoms and 4800 basis functions, with even greater gains in performance when using multithreaded CPUs (2.1 times in relation to the single-threaded CPU code using linear algebra libraries) and GPUs (3.8 times). This degree of acceleration opens new perspectives for modeling larger structures which appear in inorganic chemistry (such as zeolites and MOFs), biochemistry (such as polysaccharides, small proteins, and DNA fragments), and materials science (such as nanotubes and fullerenes). In addition, we believe that this parallel (GPU-GPU) MOPAC code will make it feasible to use semiempirical methods in lengthy molecular simulations using both hybrid QM/MM and QM/QM potentials.

21 CFR 600.2 - Mailing addresses.

Code of Federal Regulations, 2013 CFR

2013-04-01

... BIOLOGICAL PRODUCTS: GENERAL General Provisions § 600.2 Mailing addresses. (a) Licensed biological products... referenced in parts 600 through 680 of this chapter, as applicable, must be sent to: Document Control Center... applications (BLAs) and their amendments and supplements, adverse experience reports, biological product...

21 CFR 600.2 - Mailing addresses.

Code of Federal Regulations, 2014 CFR

2014-04-01

... BIOLOGICAL PRODUCTS: GENERAL General Provisions § 600.2 Mailing addresses. (a) Licensed biological products... referenced in parts 600 through 680 of this chapter, as applicable, must be sent to: Document Control Center... applications (BLAs) and their amendments and supplements, adverse experience reports, biological product...

21 CFR 600.2 - Mailing addresses.

Code of Federal Regulations, 2012 CFR

2012-04-01

... BIOLOGICAL PRODUCTS: GENERAL General Provisions § 600.2 Mailing addresses. (a) Licensed biological products... referenced in parts 600 through 680 of this chapter, as applicable, must be sent to: Document Control Center... applications (BLAs) and their amendments and supplements, adverse experience reports, biological product...

MC3, Version 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cawkwell, Marc Jon

2016-09-09

The MC3 code is used to perform Monte Carlo simulations in the isothermal-isobaric ensemble (constant number of particles, temperature, and pressure) on molecular crystals. The molecules within the periodic simulation cell are treated as rigid bodies, alleviating the requirement for a complex interatomic potential. Intermolecular interactions are described using generic, atom-centered pair potentials whose parameterization is taken from the literature [D. E. Williams, J. Comput. Chem., 22, 1154 (2001)] and electrostatic interactions arising from atom-centered, fixed, point partial charges. The primary uses of the MC3 code are the computation of i) the temperature and pressure dependence of lattice parameters andmore » thermal expansion coefficients, ii) tensors of elastic constants and compliances via the Parrinello and Rahman’s fluctuation formula [M. Parrinello and A. Rahman, J. Chem. Phys., 76, 2662 (1982)], and iii) the investigation of polymorphic phase transformations. The MC3 code is written in Fortran90 and requires LAPACK and BLAS linear algebra libraries to be linked during compilation. Computationally expensive loops are accelerated using OpenMP.« less

Storytelling Molas.

ERIC Educational Resources Information Center

Clark, Sylvia T.

1998-01-01

Recounts the creation by fifth- and sixth-grade students of their own personal "molas," based on the fabric art form of the Cuna Indians of the San Blas Islands off the coast of Panama. Tells how students created their designs based around a central image surrounded by geometric patterns and colors. (DSK)

HPC Programming on Intel Many-Integrated-Core Hardware with MAGMA Port to Xeon Phi

DOE PAGES

Dongarra, Jack; Gates, Mark; Haidar, Azzam; ...

2015-01-01

This paper presents the design and implementation of several fundamental dense linear algebra (DLA) algorithms for multicore with Intel Xeon Phi coprocessors. In particular, we consider algorithms for solving linear systems. Further, we give an overview of the MAGMA MIC library, an open source, high performance library, that incorporates the developments presented here and, more broadly, provides the DLA functionality equivalent to that of the popular LAPACK library while targeting heterogeneous architectures that feature a mix of multicore CPUs and coprocessors. The LAPACK-compliance simplifies the use of the MAGMA MIC library in applications, while providing them with portably performant DLA.more » High performance is obtained through the use of the high-performance BLAS, hardware-specific tuning, and a hybridization methodology whereby we split the algorithm into computational tasks of various granularities. Execution of those tasks is properly scheduled over the heterogeneous hardware by minimizing data movements and mapping algorithmic requirements to the architectural strengths of the various heterogeneous hardware components. Our methodology and programming techniques are incorporated into the MAGMA MIC API, which abstracts the application developer from the specifics of the Xeon Phi architecture and is therefore applicable to algorithms beyond the scope of DLA.« less

U.S. EPA, Pesticide Product Label, BUG BLAST INSECT SPRAY FOR FOGGING, 07/26/1973

EPA Pesticide Factsheets

2011-04-21

... lell •• rap Iell ,.., ttl, aId •• ,da, ftl, "'e .... ~Ic· "I lal I'" ... Id_ _t •• • I. dud , ... live ta. ai_ 101 .. EPA Reg. No. 2869-8 Bug-Blas t Is on .ff.ctiv., faat acting ...

YELLOW-BLOTCH DISEASE OUTBREAK ON REEFS OF THE SAN BLAS ISLANDS, PANAMA

EPA Science Inventory

During the post-8th International Coral Reef Symposium field trip to the eastern Caribbean region of Panama, 3-5 July 1996, we observed an extensive outbreak of a new and significant disease of the scleractinian corals Montastraea faveolata and M. annularis. The first reported si...

Parenting and Video Games

ERIC Educational Resources Information Center

Steinkuehler, Constance

2016-01-01

There is a terrific disconnect between parenting advice related to media and the realities of contemporary parenting. We condone enrichment parenting and condemn the use of "digital babysitters," admonishing parents who exceed the two-hour screen time limitation even when, all the while, no one is listening. Parents are not merely blasé…

50 CFR 226.214 - Critical habitat for Gulf sturgeon.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Mississippi, and in Mobile County, Alabama. (1) Unit 8 encompasses Lake Pontchartrain east of the Lake... boundary is the line of longitude 85°17.0′ W from its intersection with the shore (near Money Bayou between... shore (near Money Bayou between Cape San Blas and Indian Peninsula) to its intersection with the...

50 CFR 226.214 - Critical habitat for Gulf sturgeon.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Mississippi, and in Mobile County, Alabama. (1) Unit 8 encompasses Lake Pontchartrain east of the Lake... boundary is the line of longitude 85°17.0′W from its intersection with the shore (near Money Bayou between... shore (near Money Bayou between Cape San Blas and Indian Peninsula) to its intersection with the...

50 CFR 226.214 - Critical habitat for Gulf sturgeon.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Mississippi, and in Mobile County, Alabama. (1) Unit 8 encompasses Lake Pontchartrain east of the Lake... boundary is the line of longitude 85°17.0′ W from its intersection with the shore (near Money Bayou between... shore (near Money Bayou between Cape San Blas and Indian Peninsula) to its intersection with the...

50 CFR 226.214 - Critical habitat for Gulf sturgeon.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Mississippi, and in Mobile County, Alabama. (1) Unit 8 encompasses Lake Pontchartrain east of the Lake... boundary is the line of longitude 85°17.0′W from its intersection with the shore (near Money Bayou between... shore (near Money Bayou between Cape San Blas and Indian Peninsula) to its intersection with the...

50 CFR 226.214 - Critical habitat for Gulf sturgeon.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Mississippi, and in Mobile County, Alabama. (1) Unit 8 encompasses Lake Pontchartrain east of the Lake... boundary is the line of longitude 85°17.0′W from its intersection with the shore (near Money Bayou between... shore (near Money Bayou between Cape San Blas and Indian Peninsula) to its intersection with the...

Mola Interpretations: Elementary

ERIC Educational Resources Information Center

Guidetti, Mary D.

2004-01-01

In this article, the author describes how she introduced the mola designs of the Kuna people of the San Blas Islands to her fifth grade class. The students became excited by the tropical imagery; the wildlife, intertwined with the flowering plant life and the ocean, in colorful and black and-white patterns, because it brought forth such…

To remove from the John H. Chafee Coastal Barrier Resources System the areas included in Indian Peninsula Unit FL-92 and Cape San Blas Unit P-30 in Florida.

THOMAS, 112th Congress

Rep. Southerland, Steve II [R-FL-2

2012-03-07

House - 03/09/2012 Referred to the Subcommittee on Fisheries, Wildlife, Oceans, and Insular Affairs. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

To remove from the John H. Chafee Coastal Barrier Resources System the areas included in Indian Peninsula Unit FL-92 and Cape San Blas Unit P-30 in Florida.

THOMAS, 113th Congress

Rep. Southerland, Steve II [R-FL-2

2013-03-04

House - 03/07/2013 Referred to the Subcommittee on Fisheries, Wildlife, Oceans, and Insular Affairs. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

76 FR 56201 - Prescription Drug User Fee Act; Public Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-12

... PDUFA expires in September 2012. At that time, new legislation will be required for FDA to collect... and upgrade its information technology systems. At the same time, FDA committed to complete reviews in...\\ Since PDUFA was enacted, the median approval time of original NDAs and BLAs has been reduced by about 50...

Bacterial Swarms Recruit Cargo Bacteria To Pave the Way in Toxic Environments

PubMed Central

Finkelshtein, Alin; Roth, Dalit

2015-01-01

ABSTRACT Swarming bacteria are challenged by the need to invade hostile environments. Swarms of the flagellated bacterium Paenibacillus vortex can collectively transport other microorganisms. Here we show that P. vortex can invade toxic environments by carrying antibiotic-degrading bacteria; this transport is mediated by a specialized, phenotypic subpopulation utilizing a process not dependent on cargo motility. Swarms of beta-lactam antibiotic (BLA)-sensitive P. vortex used beta-lactamase-producing, resistant, cargo bacteria to detoxify BLAs in their path. In the presence of BLAs, both transporter and cargo bacteria gained from this temporary cooperation; there was a positive correlation between BLA resistance and dispersal. P. vortex transported only the most beneficial antibiotic-resistant cargo (including environmental and clinical isolates) in a sustained way. P. vortex displayed a bet-hedging strategy that promoted the colonization of nontoxic niches by P. vortex alone; when detoxifying cargo bacteria were not needed, they were lost. This work has relevance for the dispersal of antibiotic-resistant microorganisms and for strategies for asymmetric cooperation with agricultural and medical implications. PMID:25968641

Tropical Storm Blas off the Pacific Coast of Mexico

NASA Image and Video Library

2004-07-14

Tropical Storm Blas as observed by the Atmospheric Infrared Sounder AIRS onboard NASA Aqua in the year 2004. The major contribution to radiation (infrared light) that AIRS channels sense comes from different levels in the atmosphere, depending upon the channel wavelength. To create the movie, a set of AIRS channels were selected which probe the atmosphere at progressively deeper levels. If there were no clouds, the color in each frame would be nearly uniform until the Earth's surface is encountered. The tropospheric air temperature warms at a rate of 6 K (about 11 F) for each kilometer of descent toward the surface. Thus the colors would gradually change from cold to warm as the movie progresses. Clouds block the infrared radiation. Thus wherever there are clouds we can penetrate no deeper in infrared. The color remains fixed as the movie progresses, for that area of the image is "stuck" to the cloud top temperature. The coldest temperatures around 220 K (about -65 F) come from altitudes of about 10 miles. http://photojournal.jpl.nasa.gov/catalog/PIA00436

Kelp Gulls (Larus dominicanus) killed and injured by discarded monofilament lines at a marine recreational fishery in northern Patagonia.

PubMed

Yorio, Pablo; Marinao, Cristian; Suárez, Nicolás

2014-08-15

Among marine debris, monofilament fishing lines often result in negative impacts on marine organisms. We characterized marine debris and incidence of lost and discarded monofilament lines along beaches used by recreational fishers, and report the impact of lines on Kelp Gulls (Larus dominicanus) at the Bahía San Blas protected area, site of one of the main shore-based recreational fisheries of the southwestern Atlantic. Over 55% of the marine debris recorded originated from recreational fishing activities. Balls of tangled monofilament lines were found at a rate of 40.5 items per km. A total of 27 adult Kelp Gulls were found entangled with monofilament. All individuals were tangled to vegetation within colony boundaries. Four of the gulls had a monofilament line protruding from the bill, showing that they may be also killed when trying to obtain bait. Our results indicate that lost or discarded monofilament lines in the Bahía San Blas recreational fishing area result in undesired impacts on coastal wildlife. Copyright © 2014 Elsevier Ltd. All rights reserved.

Bleaching of reef coelenterates in the San Blas Islands, Panama

NASA Astrophysics Data System (ADS)

Lasker, Howard R.; Peters, Esther C.; Coffroth, Mary Alice

1984-12-01

Starting in June 1983, 25 species of hermatypic corals, gorgonians, hydrocorals, anemones and zoanthids in the San Blas Islands, Panama, began showing signs of a loss of colour leading in some cases to a white “bleached” appearance. Histologic examination of six coral species indicated that bleaching was associated with drastic reductions in the density of zooxanthellae and with the atrophy and necrosis of the animal tissue. The severity of the bleaching varied among species and many species were unaffected. The species most extensively affected were: Agaricia spp., which became completely bleached and frequently died; Montastraea annularis which bleached and continued to survive; and Millepora spp. which bleached white but quickly regained their colouration. Shallow reefs dominated by Agaricia spp. suffered the most extensive bleaching. At one site, Pico Feo, 99% of the Agaricia (32% of the living cover) was bleached. On fore reers, which were dominated by Agaricia spp. and M. annularis, the proportion of M. annularis bleached ranged from 18 to 100% and that of Agaricia spp. from 30 to 53%. Transects at Sail Rock and House Reef were surveyed in August 1983 and January 1984. At those sites, 53% of the Agaricia cover died between August and January. The remaining living cover of Agaricia and of all other species exhibited normal colouration in January. Salinity and temperature were monitored every second day at 4 m depth between May 10 and August 28, 1983 at one of the localities. Bleaching was first observed within two weeks of a 2 °C rise in temperature which occurred in late May 1983. Temperatures remained at or above 31.5 °C for the following 3 weeks and were at or above 30 °C for an additional 4 weeks. The bleaching of corals in the San Blas was most likely due to those elevanted temperatures.

Using the Intel Math Kernel Library on Peregrine | High-Performance

Science.gov Websites

Computing | NREL the Intel Math Kernel Library on Peregrine Using the Intel Math Kernel Library on Peregrine Learn how to use the Intel Math Kernel Library (MKL) with Peregrine system software. MKL architectures. Core math functions in MKL include BLAS, LAPACK, ScaLAPACK, sparse solvers, fast Fourier

Analysis of rice blast resistance genes from domesticated and weedy species of rice

USDA-ARS?s Scientific Manuscript database

Blast disease of rice caused by Magnaporthe oryzae is the most serious crop disease worldwide. The fungus is known to be highly adaptive to host environments and resistance (R) genes often do not last for an extended period of time after their deployment. In the USA, a dozen genetically diverse blas...

Matrix Algebra for GPU and Multicore Architectures (MAGMA) for Large Petascale Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dongarra, Jack J.; Tomov, Stanimire

2014-03-24

The goal of the MAGMA project is to create a new generation of linear algebra libraries that achieve the fastest possible time to an accurate solution on hybrid Multicore+GPU-based systems, using all the processing power that future high-end systems can make available within given energy constraints. Our efforts at the University of Tennessee achieved the goals set in all of the five areas identified in the proposal: 1. Communication optimal algorithms; 2. Autotuning for GPU and hybrid processors; 3. Scheduling and memory management techniques for heterogeneity and scale; 4. Fault tolerance and robustness for large scale systems; 5. Building energymore » efficiency into software foundations. The University of Tennessee’s main contributions, as proposed, were the research and software development of new algorithms for hybrid multi/many-core CPUs and GPUs, as related to two-sided factorizations and complete eigenproblem solvers, hybrid BLAS, and energy efficiency for dense, as well as sparse, operations. Furthermore, as proposed, we investigated and experimented with various techniques targeting the five main areas outlined.« less

Solution of the Skyrme-Hartree-Fock-Bogolyubov equations in the Cartesian deformed harmonic-oscillator basis.. (VII) HFODD (v2.49t): A new version of the program

NASA Astrophysics Data System (ADS)

Schunck, N.; Dobaczewski, J.; McDonnell, J.; Satuła, W.; Sheikh, J. A.; Staszczak, A.; Stoitsov, M.; Toivanen, P.

2012-01-01

We describe the new version (v2.49t) of the code HFODD which solves the nuclear Skyrme-Hartree-Fock (HF) or Skyrme-Hartree-Fock-Bogolyubov (HFB) problem by using the Cartesian deformed harmonic-oscillator basis. In the new version, we have implemented the following physics features: (i) the isospin mixing and projection, (ii) the finite-temperature formalism for the HFB and HF + BCS methods, (iii) the Lipkin translational energy correction method, (iv) the calculation of the shell correction. A number of specific numerical methods have also been implemented in order to deal with large-scale multi-constraint calculations and hardware limitations: (i) the two-basis method for the HFB method, (ii) the Augmented Lagrangian Method (ALM) for multi-constraint calculations, (iii) the linear constraint method based on the approximation of the RPA matrix for multi-constraint calculations, (iv) an interface with the axial and parity-conserving Skyrme-HFB code HFBTHO, (v) the mixing of the HF or HFB matrix elements instead of the HF fields. Special care has been paid to using the code on massively parallel leadership class computers. For this purpose, the following features are now available with this version: (i) the Message Passing Interface (MPI) framework, (ii) scalable input data routines, (iii) multi-threading via OpenMP pragmas, (iv) parallel diagonalization of the HFB matrix in the simplex-breaking case using the ScaLAPACK library. Finally, several little significant errors of the previous published version were corrected. New version program summaryProgram title:HFODD (v2.49t) Catalogue identifier: ADFL_v3_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADFL_v3_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GNU General Public Licence v3 No. of lines in distributed program, including test data, etc.: 190 614 No. of bytes in distributed program, including test data, etc.: 985 898 Distribution format: tar.gz Programming language: FORTRAN-90 Computer: Intel Pentium-III, Intel Xeon, AMD-Athlon, AMD-Opteron, Cray XT4, Cray XT5 Operating system: UNIX, LINUX, Windows XP Has the code been vectorized or parallelized?: Yes, parallelized using MPI RAM: 10 Mwords Word size: The code is written in single-precision for the use on a 64-bit processor. The compiler option -r8 or +autodblpad (or equivalent) has to be used to promote all real and complex single-precision floating-point items to double precision when the code is used on a 32-bit machine. Classification: 17.22 Catalogue identifier of previous version: ADFL_v2_2 Journal reference of previous version: Comput. Phys. Comm. 180 (2009) 2361 External routines: The user must have access to the NAGLIB subroutine f02axe, or LAPACK subroutines zhpev, zhpevx, zheevr, or zheevd, which diagonalize complex hermitian matrices, the LAPACK subroutines dgetri and dgetrf which invert arbitrary real matrices, the LAPACK subroutines dsyevd, dsytrf and dsytri which compute eigenvalues and eigenfunctions of real symmetric matrices, the LINPACK subroutines zgedi and zgeco, which invert arbitrary complex matrices and calculate determinants, the BLAS routines dcopy, dscal, dgeem and dgemv for double-precision linear algebra and zcopy, zdscal, zgeem and zgemv for complex linear algebra, or provide another set of subroutines that can perform such tasks. The BLAS and LAPACK subroutines can be obtained from the Netlib Repository at the University of Tennessee, Knoxville: http://netlib2.cs.utk.edu/. Does the new version supersede the previous version?: Yes Nature of problem: The nuclear mean field and an analysis of its symmetries in realistic cases are the main ingredients of a description of nuclear states. Within the Local Density Approximation, or for a zero-range velocity-dependent Skyrme interaction, the nuclear mean field is local and velocity dependent. The locality allows for an effective and fast solution of the self-consistent Hartree-Fock equations, even for heavy nuclei, and for various nucleonic ( n-particle- n-hole) configurations, deformations, excitation energies, or angular momenta. Similarly, Local Density Approximation in the particle-particle channel, which is equivalent to using a zero-range interaction, allows for a simple implementation of pairing effects within the Hartree-Fock-Bogolyubov method. Solution method: The program uses the Cartesian harmonic oscillator basis to expand single-particle or single-quasiparticle wave functions of neutrons and protons interacting by means of the Skyrme effective interaction and zero-range pairing interaction. The expansion coefficients are determined by the iterative diagonalization of the mean-field Hamiltonians or Routhians which depend non-linearly on the local neutron and proton densities. Suitable constraints are used to obtain states corresponding to a given configuration, deformation or angular momentum. The method of solution has been presented in: [J. Dobaczewski, J. Dudek, Comput. Phys. Commun. 102 (1997) 166]. Reasons for new version: Version 2.49s of HFODD provides a number of new options such as the isospin mixing and projection of the Skyrme functional, the finite-temperature HF and HFB formalism and optimized methods to perform multi-constrained calculations. It is also the first version of HFODD to contain threading and parallel capabilities. Summary of revisions: Isospin mixing and projection of the HF states has been implemented. The finite-temperature formalism for the HFB equations has been implemented. The Lipkin translational energy correction method has been implemented. Calculation of the shell correction has been implemented. The two-basis method for the solution to the HFB equations has been implemented. The Augmented Lagrangian Method (ALM) for calculations with multiple constraints has been implemented. The linear constraint method based on the cranking approximation of the RPA matrix has been implemented. An interface between HFODD and the axially-symmetric and parity-conserving code HFBTHO has been implemented. The mixing of the matrix elements of the HF or HFB matrix has been implemented. A parallel interface using the MPI library has been implemented. A scalable model for reading input data has been implemented. OpenMP pragmas have been implemented in three subroutines. The diagonalization of the HFB matrix in the simplex-breaking case has been parallelized using the ScaLAPACK library. Several little significant errors of the previous published version were corrected. Running time: In serial mode, running 6 HFB iterations for 152Dy for conserved parity and signature symmetries in a full spherical basis of N=14 shells takes approximately 8 min on an AMD Opteron processor at 2.6 GHz, assuming standard BLAS and LAPACK libraries. As a rule of thumb, runtime for HFB calculations for parity and signature conserved symmetries roughly increases as N, where N is the number of full HO shells. Using custom-built optimized BLAS and LAPACK libraries (such as in the ATLAS implementation) can bring down the execution time by 60%. Using the threaded version of the code with 12 threads and threaded BLAS libraries can bring an additional factor 2 speed-up, so that the same 6 HFB iterations now take of the order of 2 min 30 s.

33 CFR 80.810 - Cape San Blas, FL to Perdido Bay, FL.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., FL to Perdido Bay, FL. (a) A line drawn from St. Joseph Bay Entrance Range A Rear Light through St. Joseph Bay Entrance Range B Front Light to St. Joseph Point. (b) A line drawn across the mouth of Salt Creek as an extension of the general trend of the shoreline to continue across the inlet to St. Andrews...

New Mutations of Penicillin-Binding Proteins in Streptococcus agalactiae Isolates from Cattle with Decreased Susceptibility to Penicillin.

PubMed

Hu, Yun; Kan, Yunchao; Zhang, Zhengtian; Lu, Zhanning; Li, Yanqiu; Leng, Chaoliang; Ji, Jun; Song, Shiyang; Shi, Hongfei

2018-02-23

Streptococcus agalactiae is a causal agent of bovine mastitis and is treated by β-lactam antibiotics (BLAs). Compared to penicillin-resistant S. agalactiae from humans, resistant strains in bovine are rarely reported. In this study, we aimed to investigate BLA resistance and mutations in penicillin-binding proteins (PBPs) of S. agalactiae in central and northeast China. The minimum inhibitory concentrations (MICs) of 129 penicillin-resistant S. agalactiae isolates from cows with mastitis were determined, and the related PBP genes were detected and sequenced. All strains were unsusceptible to penicillin G and mostly resistant to ampicillin, cefalexin, and ceftiofur sodium. One hundred twenty-nine strains were divided into 4 clonal groups and 8 sequence types by multilocus sequence typing analysis. We found a set of new substitutions in PBP1B, PBP2B, and PBP2X from most strains isolated from three provinces. The strains with high PBP mutations showed a broader unsusceptible spectrum and higher MICs than those with few or single mutation. Our research indicates unpredicted mutations in the PBP genes of S. agalactiae isolated from cows with mastitis treated by BLAs. This screening is the first of S. agalactiae from cattle.

LLMapReduce: Multi-Level Map-Reduce for High Performance Data Analysis

DTIC Science & Technology

2016-05-23

LLMapReduce works with several schedulers such as SLURM, Grid Engine and LSF. Keywords—LLMapReduce; map-reduce; performance; scheduler; Grid Engine ...SLURM; LSF I. INTRODUCTION Large scale computing is currently dominated by four ecosystems: supercomputing, database, enterprise , and big data [1...interconnects [6]), High performance math libraries (e.g., BLAS [7, 8], LAPACK [9], ScaLAPACK [10]) designed to exploit special processing hardware, High

SpecTAD

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zamora, Richard; Voter, Arthur; Uberuaga, Bla

2017-10-23

The SpecTAD software represents a refactoring of the Temperature Accelerated Dynamics (TAD2) code authored by Arthur F. Voter and Blas P. Uberuaga (LA-CC-02-05). SpecTAD extends the capabilities of TAD2, by providing algorithms for both temporal and spatial parallelism. The novel algorithms for temporal parallelism include both speculation and replication based techniques. SpecTAD also offers the optional capability to dynamically link to the open-source LAMMPS package.

Linearized self-consistent quasiparticle GW method: Application to semiconductors and simple metals

NASA Astrophysics Data System (ADS)

Kutepov, A. L.; Oudovenko, V. S.; Kotliar, G.

2017-10-01

We present a code implementing the linearized quasiparticle self-consistent GW method (LQSGW) in the LAPW basis. Our approach is based on the linearization of the self-energy around zero frequency which differs it from the existing implementations of the QSGW method. The linearization allows us to use Matsubara frequencies instead of working on the real axis. This results in efficiency gains by switching to the imaginary time representation in the same way as in the space time method. The all electron LAPW basis set eliminates the need for pseudopotentials. We discuss the advantages of our approach, such as its N3 scaling with the system size N, as well as its shortcomings. We apply our approach to study the electronic properties of selected semiconductors, insulators, and simple metals and show that our code produces the results very close to the previously published QSGW data. Our implementation is a good platform for further many body diagrammatic resummations such as the vertex-corrected GW approach and the GW+DMFT method. Program Files doi:http://dx.doi.org/10.17632/cpchkfty4w.1 Licensing provisions: GNU General Public License Programming language: Fortran 90 External routines/libraries: BLAS, LAPACK, MPI (optional) Nature of problem: Direct implementation of the GW method scales as N4 with the system size, which quickly becomes prohibitively time consuming even in the modern computers. Solution method: We implemented the GW approach using a method that switches between real space and momentum space representations. Some operations are faster in real space, whereas others are more computationally efficient in the reciprocal space. This makes our approach scale as N3. Restrictions: The limiting factor is usually the memory available in a computer. Using 10 GB/core of memory allows us to study the systems up to 15 atoms per unit cell.

High-Performance Analysis of Filtered Semantic Graphs

DTIC Science & Technology

2012-05-06

any other provision of law, no person shall be subject to a penalty for failing to comply with a collection of information if it does not display a...observation that explains why SEJITS+KDT performance is so close to CombBLAS performance in practice (as shown later in Section 7) even though its in-core...NEC, Nokia , NVIDIA, Oracle, and Samsung. This research used resources of the National Energy Research Sci- entific Computing Center, which is

Incremental growth of an upper crustal, A-type pluton, Argentina: Evidence of a re-used magma pathway

NASA Astrophysics Data System (ADS)

Alasino, Pablo H.; Larrovere, Mariano A.; Rocher, Sebastián; Dahlquist, Juan A.; Basei, Miguel A. S.; Memeti, Valbone; Paterson, Scott; Galindo, Carmen; Macchioli Grande, Marcos; da Costa Campos Neto, Mario

2017-07-01

Carboniferous igneous activity in the Sierra de Velasco (NW Argentina) led to the emplacement of several magmas bodies at shallow levels (< 2 kbar). One of these, the San Blas intrusive complex formed over millions of years (≤ 2-3 m.y.) through three periods of magma additions that are characterized by variations in magma sources and emplacement style. The main units, mostly felsic granitoids, have U-Pb zircon crystallization ages within the error range. From older to younger (based on cross-cutting relationships) intrusive units are: (1) the Asha unit (340 ± 7 Ma): a tabular to funnel-shaped intrusion emplaced during a regional strain field dominated by WSW-ENE shortening with contacts discordant to regional host-rock structures; (2) the San Blas unit (344 ± 2 Ma): an approximate cylindrical-shaped intrusion formed by multiple batches of magmas, with a roughly concentric fabric pattern and displacement of the host rock by ductile flow of about 35% of shortening; and (3) the Hualco unit (346 ± 6 Ma): a small body with a possible mushroom geometry and contacts concordant to regional host-rock structures. The magma pulses making up these units define two groups of A-type granitoids. The first group includes the peraluminous granitic rocks of the Asha unit generated mostly by crustal sources (εNdt = - 5.8 and εHft in zircon = - 2.9 to - 4.5). The second group comprises the metaluminous to peraluminous granitic rocks of the youngest units (San Blas and Hualco), which were formed by a heterogeneous mixture between mantle and crustal sources (εNdt = + 0.6 to - 4.8 and εHft in zircon = + 3 to - 6). Our results provide a comprehensive view of the evolution of an intrusive complex formed from multiple non-consanguineous magma intrusions that utilized the same magmatic plumbing system during downward transfer of host materials. As the plutonic system matures, the ascent of magmas is governed by the visco-elastic flow of host rock that for younger batches include older hot magma mush. The latter results in ductile downward flow of older, during rise of younger magma. Such complexes may reflect the plutonic portion of volcanic centers where chemically distinct magmas are erupted.

Bethe-Salpeter Eigenvalue Solver Package (BSEPACK) v0.1

DOE Office of Scientific and Technical Information (OSTI.GOV)

SHAO, MEIYEU; YANG, CHAO

2017-04-25

The BSEPACK contains a set of subroutines for solving the Bethe-Salpeter Eigenvalue (BSE) problem. This type of problem arises in this study of optical excitation of nanoscale materials. The BSE problem is a structured non-Hermitian eigenvalue problem. The BSEPACK software can be used to compute all or subset of eigenpairs of a BSE Hamiltonian. It can also be used to compute the optical absorption spectrum without computing BSE eigenvalues and eigenvectors explicitly. The package makes use of the ScaLAPACK, LAPACK and BLAS.

Applications Performance on NAS Intel Paragon XP/S - 15#

NASA Technical Reports Server (NTRS)

Saini, Subhash; Simon, Horst D.; Copper, D. M. (Technical Monitor)

1994-01-01

The Numerical Aerodynamic Simulation (NAS) Systems Division received an Intel Touchstone Sigma prototype model Paragon XP/S- 15 in February, 1993. The i860 XP microprocessor with an integrated floating point unit and operating in dual -instruction mode gives peak performance of 75 million floating point operations (NIFLOPS) per second for 64 bit floating point arithmetic. It is used in the Paragon XP/S-15 which has been installed at NAS, NASA Ames Research Center. The NAS Paragon has 208 nodes and its peak performance is 15.6 GFLOPS. Here, we will report on early experience using the Paragon XP/S- 15. We have tested its performance using both kernels and applications of interest to NAS. We have measured the performance of BLAS 1, 2 and 3 both assembly-coded and Fortran coded on NAS Paragon XP/S- 15. Furthermore, we have investigated the performance of a single node one-dimensional FFT, a distributed two-dimensional FFT and a distributed three-dimensional FFT Finally, we measured the performance of NAS Parallel Benchmarks (NPB) on the Paragon and compare it with the performance obtained on other highly parallel machines, such as CM-5, CRAY T3D, IBM SP I, etc. In particular, we investigated the following issues, which can strongly affect the performance of the Paragon: a. Impact of the operating system: Intel currently uses as a default an operating system OSF/1 AD from the Open Software Foundation. The paging of Open Software Foundation (OSF) server at 22 MB to make more memory available for the application degrades the performance. We found that when the limit of 26 NIB per node out of 32 MB available is reached, the application is paged out of main memory using virtual memory. When the application starts paging, the performance is considerably reduced. We found that dynamic memory allocation can help applications performance under certain circumstances. b. Impact of data cache on the i860/XP: We measured the performance of the BLAS both assembly coded and Fortran coded. We found that the measured performance of assembly-coded BLAS is much less than what memory bandwidth limitation would predict. The influence of data cache on different sizes of vectors is also investigated using one-dimensional FFTs. c. Impact of processor layout: There are several different ways processors can be laid out within the two-dimensional grid of processors on the Paragon. We have used the FFT example to investigate performance differences based on processors layout.

PONS2train: tool for testing the MLP architecture and local traning methods for runoff forecast

NASA Astrophysics Data System (ADS)

Maca, P.; Pavlasek, J.; Pech, P.

2012-04-01

The purpose of presented poster is to introduce the PONS2train developed for runoff prediction via multilayer perceptron - MLP. The software application enables the implementation of 12 different MLP's transfer functions, comparison of 9 local training algorithms and finally the evaluation the MLP performance via 17 selected model evaluation metrics. The PONS2train software is written in C++ programing language. Its implementation consists of 4 classes. The NEURAL_NET and NEURON classes implement the MLP, the CRITERIA class estimates model evaluation metrics and for model performance evaluation via testing and validation datasets. The DATA_PATTERN class prepares the validation, testing and calibration datasets. The software application uses the LAPACK, BLAS and ARMADILLO C++ linear algebra libraries. The PONS2train implements the first order local optimization algorithms: standard on-line and batch back-propagation with learning rate combined with momentum and its variants with the regularization term, Rprop and standard batch back-propagation with variable momentum and learning rate. The second order local training algorithms represents: the Levenberg-Marquardt algorithm with and without regularization and four variants of scaled conjugate gradients. The other important PONS2train features are: the multi-run, the weight saturation control, early stopping of trainings, and the MLP weights analysis. The weights initialization is done via two different methods: random sampling from uniform distribution on open interval or Nguyen Widrow method. The data patterns can be transformed via linear and nonlinear transformation. The runoff forecast case study focuses on PONS2train implementation and shows the different aspects of the MLP training, the MLP architecture estimation, the neural network weights analysis and model uncertainty estimation.

Study of high-performance canonical molecular orbitals calculation for proteins

NASA Astrophysics Data System (ADS)

Hirano, Toshiyuki; Sato, Fumitoshi

2017-11-01

The canonical molecular orbital (CMO) calculation can help to understand chemical properties and reactions in proteins. However, it is difficult to perform the CMO calculation of proteins because of its self-consistent field (SCF) convergence problem and expensive computational cost. To certainly obtain the CMO of proteins, we work in research and development of high-performance CMO applications and perform experimental studies. We have proposed the third-generation density-functional calculation method of calculating the SCF, which is more advanced than the FILE and direct method. Our method is based on Cholesky decomposition for two-electron integrals calculation and the modified grid-free method for the pure-XC term evaluation. By using the third-generation density-functional calculation method, the Coulomb, the Fock-exchange, and the pure-XC terms can be given by simple linear algebraic procedure in the SCF loop. Therefore, we can expect to get a good parallel performance in solving the SCF problem by using a well-optimized linear algebra library such as BLAS on the distributed memory parallel computers. The third-generation density-functional calculation method is implemented to our program, ProteinDF. To achieve computing electronic structure of the large molecule, not only overcoming expensive computation cost and also good initial guess for safe SCF convergence are required. In order to prepare a precise initial guess for the macromolecular system, we have developed the quasi-canonical localized orbital (QCLO) method. The QCLO has the characteristics of both localized and canonical orbital in a certain region of the molecule. We have succeeded in the CMO calculations of proteins by using the QCLO method. For simplified and semi-automated calculation of the QCLO method, we have also developed a Python-based program, QCLObot.

Oral Contraceptives Use by Young Woman Reduces Peak Bone Mass

DTIC Science & Technology

1999-09-01

Alphacel 10.0 Lard 5.20 Safflower Oil (linoleic) 1.00 Choline Bitartrate 0.20 Vitamin Mixture, AIN-76A 1.00 Mineral Mix, AIN-76 3.50 On Nov...774-9,1970 Modrowoski D, del Pozo E, Miravet L . Horm Metab Res 24(10):474-477, 1992. Parfitt AM, Drezner MK, Glorieux FH, et al. J Bone Mineral Res...Register.1 C. L . Hughes.*2 U. Blas- Machado.*1 E. Sulistiawati.*’ P. W. Louderback.*1 S. E. Rankin.*1 ’Pathology/Comparative Medicine, Wake Forest

Feasibility and Guidelines for the Development of Microgrids on Campus-Type Facilities

DTIC Science & Technology

2012-04-01

1.38066e-23 (J/K) q : Elementary charge, 1.60218e-19( coulomb ) Eqs (4) and (6) have two unknowns, which are C0 and C1. By using the data from I-V...Vol. 69, Iss. 3, 2000. [13] M. A. de blas, J.L. Torres, E. Prieto and A. Garcia, “Selecting a suitable model for characterizing photovoltaic...vol., no., pp. 108-112, 16-18 March 2003. [22] Y. Lei , A. Mullane, G. Lightbody, R. Yacamini, "Modeling of the wind turbine with a doubly fed

Recent advances in PC-Linux systems for electronic structure computations by optimized compilers and numerical libraries.

PubMed

Yu, Jen-Shiang K; Yu, Chin-Hui

2002-01-01

One of the most frequently used packages for electronic structure research, GAUSSIAN 98, is compiled on Linux systems with various hardware configurations, including AMD Athlon (with the "Thunderbird" core), AthlonMP, and AthlonXP (with the "Palomino" core) systems as well as the Intel Pentium 4 (with the "Willamette" core) machines. The default PGI FORTRAN compiler (pgf77) and the Intel FORTRAN compiler (ifc) are respectively employed with different architectural optimization options to compile GAUSSIAN 98 and test the performance improvement. In addition to the BLAS library included in revision A.11 of this package, the Automatically Tuned Linear Algebra Software (ATLAS) library is linked against the binary executables to improve the performance. Various Hartree-Fock, density-functional theories, and the MP2 calculations are done for benchmarking purposes. It is found that the combination of ifc with ATLAS library gives the best performance for GAUSSIAN 98 on all of these PC-Linux computers, including AMD and Intel CPUs. Even on AMD systems, the Intel FORTRAN compiler invariably produces binaries with better performance than pgf77. The enhancement provided by the ATLAS library is more significant for post-Hartree-Fock calculations. The performance on one single CPU is potentially as good as that on an Alpha 21264A workstation or an SGI supercomputer. The floating-point marks by SpecFP2000 have similar trends to the results of GAUSSIAN 98 package.

An Array Library for Microsoft SQL Server with Astrophysical Applications

NASA Astrophysics Data System (ADS)

Dobos, L.; Szalay, A. S.; Blakeley, J.; Falck, B.; Budavári, T.; Csabai, I.

2012-09-01

Today's scientific simulations produce output on the 10-100 TB scale. This unprecedented amount of data requires data handling techniques that are beyond what is used for ordinary files. Relational database systems have been successfully used to store and process scientific data, but the new requirements constantly generate new challenges. Moving terabytes of data among servers on a timely basis is a tough problem, even with the newest high-throughput networks. Thus, moving the computations as close to the data as possible and minimizing the client-server overhead are absolutely necessary. At least data subsetting and preprocessing have to be done inside the server process. Out of the box commercial database systems perform very well in scientific applications from the prospective of data storage optimization, data retrieval, and memory management but lack basic functionality like handling scientific data structures or enabling advanced math inside the database server. The most important gap in Microsoft SQL Server is the lack of a native array data type. Fortunately, the technology exists to extend the database server with custom-written code that enables us to address these problems. We present the prototype of a custom-built extension to Microsoft SQL Server that adds array handling functionality to the database system. With our Array Library, fix-sized arrays of all basic numeric data types can be created and manipulated efficiently. Also, the library is designed to be able to be seamlessly integrated with the most common math libraries, such as BLAS, LAPACK, FFTW, etc. With the help of these libraries, complex operations, such as matrix inversions or Fourier transformations, can be done on-the-fly, from SQL code, inside the database server process. We are currently testing the prototype with two different scientific data sets: The Indra cosmological simulation will use it to store particle and density data from N-body simulations, and the Milky Way Laboratory project will use it to store galaxy simulation data.

Mechanical design of deformation compensated flexural pivots structured for linear nanopositioning stages

DOEpatents

Shu, Deming; Kearney, Steven P.; Preissner, Curt A.

2015-02-17

A method and deformation compensated flexural pivots structured for precision linear nanopositioning stages are provided. A deformation-compensated flexural linear guiding mechanism includes a basic parallel mechanism including a U-shaped member and a pair of parallel bars linked to respective pairs of I-link bars and each of the I-bars coupled by a respective pair of flexural pivots. The basic parallel mechanism includes substantially evenly distributed flexural pivots minimizing center shift dynamic errors.

Mathematical Techniques for Nonlinear System Theory.

DTIC Science & Technology

1981-09-01

This report deals with research results obtained in the following areas: (1) Finite-dimensional linear system theory by algebraic methods--linear...Infinite-dimensional linear systems--realization theory of infinite-dimensional linear systems; (3) Nonlinear system theory --basic properties of

An Extension of the Partial Credit Model with an Application to the Measurement of Change.

ERIC Educational Resources Information Center

Fischer, Gerhard H.; Ponocny, Ivo

1994-01-01

An extension to the partial credit model, the linear partial credit model, is considered under the assumption of a certain linear decomposition of the item x category parameters into basic parameters. A conditional maximum likelihood algorithm for estimating basic parameters is presented and illustrated with simulation and an empirical study. (SLD)

Fixed-Dose Combination Drug Approvals, Patents and Market Exclusivities Compared to Single Active Ingredient Pharmaceuticals.

PubMed

Hao, Jing; Rodriguez-Monguio, Rosa; Seoane-Vazquez, Enrique

2015-01-01

Fixed-dose combinations (FDC) contain two or more active ingredients. The effective patent and exclusivity life of FDC compared to single active ingredient has not been assessed. Trends in FDA approved FDC in the period 1980-2012 and time lag between approval of FDC and single active ingredients in the combination were assessed, and the effective patent and exclusivity life of FDC was compared with their single active ingredients. New molecular entities (NMEs), new therapeutic biologics license applications (BLAs) and FDC data were collected from the FDA Orange Book and Drugs@FDA. Analysis included FDC containing one or more NMEs or BLAs at first FDA approval (NMEs-FDC) and only already marketed drugs (Non-NMEs-FDC). Descriptive, Kruskal-Wallis and Wilcoxon Rank Sum analyses were performed. During the study period, the FDA approved 28 NMEs-FDC (3.5% of NMEs) and 117 non-NMEs-FDC. FDC approvals increased from 12 in the 1980s to 59 in the 2000s. Non-NMEs-FDC entered the market at a median of 5.43 years (interquartile range 1.74, 10.31) after first FDA approval of single active ingredients in the combination. The Non-NMEs-FDC entered the market at a median of 2.33 years (-7.55, 2.39) before approval of generic single active ingredient. Non-NME-FDC added a median of 9.70 (2.75, 16.24) years to the patent and exclusivity life of the single active ingredients in the combination. FDC approvals significantly increased over the last twenty years. Pharmaceutical companies market FDC drugs shortly before the generic versions of the single ingredients enter the market extending the patent and exclusivity life of drugs included in the combination.

Variability simulations with a steady, linearized primitive equations model

NASA Technical Reports Server (NTRS)

Kinter, J. L., III; Nigam, S.

1985-01-01

Solutions of the steady, primitive equations on a sphere, linearized about a zonally symmetric basic state are computed for the purpose of simulating monthly mean variability in the troposphere. The basic states are observed, winter monthly mean, zonal means of zontal and meridional velocities, temperatures and surface pressures computed from the 15 year NMC time series. A least squares fit to a series of Legendre polynomials is used to compute the basic states between 20 H and the equator, and the hemispheres are assumed symmetric. The model is spectral in the zonal direction, and centered differences are employed in the meridional and vertical directions. Since the model is steady and linear, the solution is obtained by inversion of a block, pente-diagonal matrix. The model simulates the climatology of the GFDL nine level, spectral general circulation model quite closely, particularly in middle latitudes above the boundary layer. This experiment is an extension of that simulation to examine variability of the steady, linear solution.

Military Curricula for Vocational & Technical Education. Basic Electricity and Electronics. CANTRAC A-100-0010. Module 34: Linear Integrated Circuits. Study Booklet.

ERIC Educational Resources Information Center

Chief of Naval Education and Training Support, Pensacola, FL.

This individualized learning module on linear integrated circuits is one in a series of modules for a course in basic electricity and electronics. The course is one of a number of military-developed curriculum packages selected for adaptation to vocational instructional and curriculum development in a civilian setting. Two lessons are included in…

Number games, magnitude representation, and basic number skills in preschoolers.

PubMed

Whyte, Jemma Catherine; Bull, Rebecca

2008-03-01

The effect of 3 intervention board games (linear number, linear color, and nonlinear number) on young children's (mean age = 3.8 years) counting abilities, number naming, magnitude comprehension, accuracy in number-to-position estimation tasks, and best-fit numerical magnitude representations was examined. Pre- and posttest performance was compared following four 25-min intervention sessions. The linear number board game significantly improved children's performance in all posttest measures and facilitated a shift from a logarithmic to a linear representation of numerical magnitude, emphasizing the importance of spatial cues in estimation. Exposure to the number card games involving nonsymbolic magnitude judgments and association of symbolic and nonsymbolic quantities, but without any linear spatial cues, improved some aspects of children's basic number skills but not numerical estimation precision.

Real-time radar signal processing using GPGPU (general-purpose graphic processing unit)

NASA Astrophysics Data System (ADS)

Kong, Fanxing; Zhang, Yan Rockee; Cai, Jingxiao; Palmer, Robert D.

2016-05-01

This study introduces a practical approach to develop real-time signal processing chain for general phased array radar on NVIDIA GPUs(Graphical Processing Units) using CUDA (Compute Unified Device Architecture) libraries such as cuBlas and cuFFT, which are adopted from open source libraries and optimized for the NVIDIA GPUs. The processed results are rigorously verified against those from the CPUs. Performance benchmarked in computation time with various input data cube sizes are compared across GPUs and CPUs. Through the analysis, it will be demonstrated that GPGPUs (General Purpose GPU) real-time processing of the array radar data is possible with relatively low-cost commercial GPUs.

Increased incidence of red imported fire ant (Hymenoptera: Formicidae) presence in loggerhead sea turtle (Testudines: Cheloniidae) nests and observations of hatchling mortality

USGS Publications Warehouse

Parris, L.B.; Lamont, M.M.; Carthy, R.R.

2002-01-01

Hatching sea turtles may be at risk to fire ant predation during egg incubation, and especially at risk once pipped from the egg, prior to hatchling emergence from the nest. In addition to direct mortality, fire ants have the potential to inflict debilitating injuries that may directly affect survival of the young. The increased incidence of red imported fire ant induced mortality and envenomization of loggerhead sea turtle hatchlings on Cape San Blas suggests this invasive ant species may pose a serious threat to the future of this genetically distinct population.

Towards Batched Linear Solvers on Accelerated Hardware Platforms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Haidar, Azzam; Dong, Tingzing Tim; Tomov, Stanimire

2015-01-01

As hardware evolves, an increasingly effective approach to develop energy efficient, high-performance solvers, is to design them to work on many small and independent problems. Indeed, many applications already need this functionality, especially for GPUs, which are known to be currently about four to five times more energy efficient than multicore CPUs for every floating-point operation. In this paper, we describe the development of the main one-sided factorizations: LU, QR, and Cholesky; that are needed for a set of small dense matrices to work in parallel. We refer to such algorithms as batched factorizations. Our approach is based on representingmore » the algorithms as a sequence of batched BLAS routines for GPU-contained execution. Note that this is similar in functionality to the LAPACK and the hybrid MAGMA algorithms for large-matrix factorizations. But it is different from a straightforward approach, whereby each of GPU's symmetric multiprocessors factorizes a single problem at a time. We illustrate how our performance analysis together with the profiling and tracing tools guided the development of batched factorizations to achieve up to 2-fold speedup and 3-fold better energy efficiency compared to our highly optimized batched CPU implementations based on the MKL library on a two-sockets, Intel Sandy Bridge server. Compared to a batched LU factorization featured in the NVIDIA's CUBLAS library for GPUs, we achieves up to 2.5-fold speedup on the K40 GPU.« less

Stochastic hyperfine interactions modeling library

NASA Astrophysics Data System (ADS)

Zacate, Matthew O.; Evenson, William E.

2011-04-01

The stochastic hyperfine interactions modeling library (SHIML) provides a set of routines to assist in the development and application of stochastic models of hyperfine interactions. The library provides routines written in the C programming language that (1) read a text description of a model for fluctuating hyperfine fields, (2) set up the Blume matrix, upon which the evolution operator of the system depends, and (3) find the eigenvalues and eigenvectors of the Blume matrix so that theoretical spectra of experimental techniques that measure hyperfine interactions can be calculated. The optimized vector and matrix operations of the BLAS and LAPACK libraries are utilized; however, there was a need to develop supplementary code to find an orthonormal set of (left and right) eigenvectors of complex, non-Hermitian matrices. In addition, example code is provided to illustrate the use of SHIML to generate perturbed angular correlation spectra for the special case of polycrystalline samples when anisotropy terms of higher order than A can be neglected. Program summaryProgram title: SHIML Catalogue identifier: AEIF_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEIF_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GNU GPL 3 No. of lines in distributed program, including test data, etc.: 8224 No. of bytes in distributed program, including test data, etc.: 312 348 Distribution format: tar.gz Programming language: C Computer: Any Operating system: LINUX, OS X RAM: Varies Classification: 7.4 External routines: TAPP [1], BLAS [2], a C-interface to BLAS [3], and LAPACK [4] Nature of problem: In condensed matter systems, hyperfine methods such as nuclear magnetic resonance (NMR), Mössbauer effect (ME), muon spin rotation (μSR), and perturbed angular correlation spectroscopy (PAC) measure electronic and magnetic structure within Angstroms of nuclear probes through the hyperfine interaction. When interactions fluctuate at rates comparable to the time scale of a hyperfine method, there is a loss in signal coherence, and spectra are damped. The degree of damping can be used to determine fluctuation rates, provided that theoretical expressions for spectra can be derived for relevant physical models of the fluctuations. SHIML provides routines to help researchers quickly develop code to incorporate stochastic models of fluctuating hyperfine interactions in calculations of hyperfine spectra. Solution method: Calculations are based on the method for modeling stochastic hyperfine interactions for PAC by Winkler and Gerdau [5]. The method is extended to include other hyperfine methods following the work of Dattagupta [6]. The code provides routines for reading model information from text files, allowing researchers to develop new models quickly without the need to modify computer code for each new model to be considered. Restrictions: In the present version of the code, only methods that measure the hyperfine interaction on one probe spin state, such as PAC, μSR, and NMR, are supported. Running time: Varies

Point Cloud Management Through the Realization of the Intelligent Cloud Viewer Software

NASA Astrophysics Data System (ADS)

Costantino, D.; Angelini, M. G.; Settembrini, F.

2017-05-01

The paper presents a software dedicated to the elaboration of point clouds, called Intelligent Cloud Viewer (ICV), made in-house by AESEI software (Spin-Off of Politecnico di Bari), allowing to view point cloud of several tens of millions of points, also on of "no" very high performance systems. The elaborations are carried out on the whole point cloud and managed by means of the display only part of it in order to speed up rendering. It is designed for 64-bit Windows and is fully written in C ++ and integrates different specialized modules for computer graphics (Open Inventor by SGI, Silicon Graphics Inc), maths (BLAS, EIGEN), computational geometry (CGAL, Computational Geometry Algorithms Library), registration and advanced algorithms for point clouds (PCL, Point Cloud Library), advanced data structures (BOOST, Basic Object Oriented Supporting Tools), etc. ICV incorporates a number of features such as, for example, cropping, transformation and georeferencing, matching, registration, decimation, sections, distances calculation between clouds, etc. It has been tested on photographic and TLS (Terrestrial Laser Scanner) data, obtaining satisfactory results. The potentialities of the software have been tested by carrying out the photogrammetric survey of the Castel del Monte which was already available in previous laser scanner survey made from the ground by the same authors. For the aerophotogrammetric survey has been adopted a flight height of approximately 1000ft AGL (Above Ground Level) and, overall, have been acquired over 800 photos in just over 15 minutes, with a covering not less than 80%, the planned speed of about 90 knots.

Using Example Generation to Explore Students' Understanding of the Concepts of Linear Dependence/Independence in Linear Algebra

ERIC Educational Resources Information Center

Aydin, Sinan

2014-01-01

Linear algebra is a basic mathematical subject taught in mathematics and science depar-tments of universities. The teaching and learning of this course has always been difficult. This study aims to contribute to the research in linear algebra education, focusing on linear dependence and independence concepts. This was done by introducing…

Using Theoretical Descriptors in Structural Activity Relationships: 4. Molecular Orbital Basicity and Electrostatic Basicity

DTIC Science & Technology

1988-11-01

rates.6 The Hammet equation , also called the Linear Free Energy Relationship (LFER) because of the relationship of the Gibb’s Free Energy to the... equations for numerous biological and physicochemical properties. Linear Solvation Enery Relationship (LSER), a sub-set of QSAR have been used by...originates from thermodynamics, where Hammet recognized the relationship of structure to the Gibb’s Free Energy, and ultimately to equilibria and reaction

Lie algebras and linear differential equations.

NASA Technical Reports Server (NTRS)

Brockett, R. W.; Rahimi, A.

1972-01-01

Certain symmetry properties possessed by the solutions of linear differential equations are examined. For this purpose, some basic ideas from the theory of finite dimensional linear systems are used together with the work of Wei and Norman on the use of Lie algebraic methods in differential equation theory.

Software Reviews.

ERIC Educational Resources Information Center

Mathematics and Computer Education, 1987

1987-01-01

Presented are reviews of several microcomputer software programs. Included are reviews of: (1) Microstat (Zenith); (2) MathCAD (MathSoft); (3) Discrete Mathematics (True Basic); (4) CALCULUS (True Basic); (5) Linear-Kit (John Wiley); and (6) Geometry Sensei (Broderbund). (RH)

Development of a Multiple Linear Regression Model to Forecast Facility Electrical Consumption at an Air Force Base.

DTIC Science & Technology

1981-09-01

corresponds to the same square footage that consumed the electrical energy. 3. The basic assumptions of multiple linear regres- sion, as enumerated in...7. Data related to the sample of bases is assumed to be representative of bases in the population. Limitations Basic limitations on this research were... Ratemaking --Overview. Rand Report R-5894, Santa Monica CA, May 1977. Chatterjee, Samprit, and Bertram Price. Regression Analysis by Example. New York: John

Artificial Intelligence Methodologies in Flight Related Differential Game, Control and Optimization Problems

DTIC Science & Technology

1993-01-31

28 Controllability and Observability ............................. .32 ’ Separation of Learning and Control ... ... 37 Linearization via... Linearization via Transformation of Coordinates and Nonlinear Fedlback . .1 Main Result ......... .............................. 13 Discussion...9 2.1 Basic Structure of a NLM........................ .󈧟 2.2 General Structure of NNLM .......................... .28 2.3 Linear System

Relations between basic and specific motor abilities and player quality of young basketball players.

PubMed

Marić, Kristijan; Katić, Ratko; Jelicić, Mario

2013-05-01

Subjects from 5 first league clubs from Herzegovina were tested with the purpose of determining the relations of basic and specific motor abilities, as well as the effect of specific abilities on player efficiency in young basketball players (cadets). A battery of 12 tests assessing basic motor abilities and 5 specific tests assessing basketball efficiency were used on a sample of 83 basketball players. Two significant canonical correlations, i.e. linear combinations explained the relation between the set of twelve variables of basic motor space and five variables of situational motor abilities. Underlying the first canonical linear combination is the positive effect of the general motor factor, predominantly defined by jumping explosive power, movement speed of the arms, static strength of the arms and coordination, on specific basketball abilities: movement efficiency, the power of the overarm throw, shooting and passing precision, and the skill of handling the ball. The impact of basic motor abilities of precision and balance on specific abilities of passing and shooting precision and ball handling is underlying the second linear combination. The results of regression correlation analysis between the variable set of specific motor abilities and game efficiency have shown that the ability of ball handling has the largest impact on player quality in basketball cadets, followed by shooting precision and passing precision, and the power of the overarm throw.

Controllability of complex networks for sustainable system dynamics

EPA Science Inventory

Successful implementation of sustainability ideas in ecosystem management requires a basic understanding of the often non-linear and non-intuitive relationships among different dimensions of sustainability, particularly the system-wide implications of human actions. This basic un...

A HUBBLE SPACE TELESCOPE/COSMIC ORIGINS SPECTROGRAPH SEARCH FOR WARM-HOT BARYONS IN THE Mrk 421 SIGHT LINE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Danforth, Charles W.; Stocke, John T.; Keeney, Brian A.

2011-12-10

Thermally broadened Ly{alpha} absorbers (BLAs) offer an alternate method to using highly ionized metal absorbers (O VI, O VII, etc.) to probe the warm-hot intergalactic medium (WHIM, T = 10{sup 5}-10{sup 7} K). Until now, WHIM surveys via BLAs have been no less ambiguous than those via far-UV and X-ray metal-ion probes. Detecting these weak, broad features requires background sources with a well-characterized far-UV continuum and data of very high quality. However, a recent Hubble Space Telescope/Cosmic Origins Spectrograph (COS) observation of the z = 0.03 blazar Mrk 421 allows us to perform a metal-independent search for WHIM gas withmore » unprecedented precision. The data have high signal-to-noise ratio (S/N Almost-Equal-To 50 per {approx}20 km s{sup -1} resolution element) and the smooth, power-law blazar spectrum allows a fully parametric continuum model. We analyze the Mrk 421 sight line for BLA absorbers, particularly for counterparts to the proposed O VII WHIM systems reported by Nicastro et al. based on Chandra/Low Energy Transmission Grating observations. We derive the Ly{alpha} profiles predicted by the X-ray observations. The S/N of the COS data is high (S/N Almost-Equal-To 25 pixel{sup -1}), but much higher S/N can be obtained by binning the data to widths characteristic of the expected BLA profiles. With this technique, we are sensitive to WHIM gas over a large (N{sub H}, T) parameter range in the Mrk 421 sight line. We rule out the claimed Nicastro et al. O VII detections at their nominal temperatures (T {approx} 1-2 Multiplication-Sign 10{sup 6} K) and metallicities (Z = 0.1 Z{sub Sun }) at {approx}> 2{sigma} level. However, WHIM gas at higher temperatures and/or higher metallicities is consistent with our COS non-detections.« less

A High Performance Block Eigensolver for Nuclear Configuration Interaction Calculations

DOE PAGES

Aktulga, Hasan Metin; Afibuzzaman, Md.; Williams, Samuel; ...

2017-06-01

As on-node parallelism increases and the performance gap between the processor and the memory system widens, achieving high performance in large-scale scientific applications requires an architecture-aware design of algorithms and solvers. We focus on the eigenvalue problem arising in nuclear Configuration Interaction (CI) calculations, where a few extreme eigenpairs of a sparse symmetric matrix are needed. Here, we consider a block iterative eigensolver whose main computational kernels are the multiplication of a sparse matrix with multiple vectors (SpMM), and tall-skinny matrix operations. We then present techniques to significantly improve the SpMM and the transpose operation SpMM T by using themore » compressed sparse blocks (CSB) format. We achieve 3-4× speedup on the requisite operations over good implementations with the commonly used compressed sparse row (CSR) format. We develop a performance model that allows us to correctly estimate the performance of our SpMM kernel implementations, and we identify cache bandwidth as a potential performance bottleneck beyond DRAM. We also analyze and optimize the performance of LOBPCG kernels (inner product and linear combinations on multiple vectors) and show up to 15× speedup over using high performance BLAS libraries for these operations. The resulting high performance LOBPCG solver achieves 1.4× to 1.8× speedup over the existing Lanczos solver on a series of CI computations on high-end multicore architectures (Intel Xeons). We also analyze the performance of our techniques on an Intel Xeon Phi Knights Corner (KNC) processor.« less

FWT2D: A massively parallel program for frequency-domain full-waveform tomography of wide-aperture seismic data—Part 1: Algorithm

NASA Astrophysics Data System (ADS)

Sourbier, Florent; Operto, Stéphane; Virieux, Jean; Amestoy, Patrick; L'Excellent, Jean-Yves

2009-03-01

This is the first paper in a two-part series that describes a massively parallel code that performs 2D frequency-domain full-waveform inversion of wide-aperture seismic data for imaging complex structures. Full-waveform inversion methods, namely quantitative seismic imaging methods based on the resolution of the full wave equation, are computationally expensive. Therefore, designing efficient algorithms which take advantage of parallel computing facilities is critical for the appraisal of these approaches when applied to representative case studies and for further improvements. Full-waveform modelling requires the resolution of a large sparse system of linear equations which is performed with the massively parallel direct solver MUMPS for efficient multiple-shot simulations. Efficiency of the multiple-shot solution phase (forward/backward substitutions) is improved by using the BLAS3 library. The inverse problem relies on a classic local optimization approach implemented with a gradient method. The direct solver returns the multiple-shot wavefield solutions distributed over the processors according to a domain decomposition driven by the distribution of the LU factors. The domain decomposition of the wavefield solutions is used to compute in parallel the gradient of the objective function and the diagonal Hessian, this latter providing a suitable scaling of the gradient. The algorithm allows one to test different strategies for multiscale frequency inversion ranging from successive mono-frequency inversion to simultaneous multifrequency inversion. These different inversion strategies will be illustrated in the following companion paper. The parallel efficiency and the scalability of the code will also be quantified.

A High Performance Block Eigensolver for Nuclear Configuration Interaction Calculations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aktulga, Hasan Metin; Afibuzzaman, Md.; Williams, Samuel

As on-node parallelism increases and the performance gap between the processor and the memory system widens, achieving high performance in large-scale scientific applications requires an architecture-aware design of algorithms and solvers. We focus on the eigenvalue problem arising in nuclear Configuration Interaction (CI) calculations, where a few extreme eigenpairs of a sparse symmetric matrix are needed. Here, we consider a block iterative eigensolver whose main computational kernels are the multiplication of a sparse matrix with multiple vectors (SpMM), and tall-skinny matrix operations. We then present techniques to significantly improve the SpMM and the transpose operation SpMM T by using themore » compressed sparse blocks (CSB) format. We achieve 3-4× speedup on the requisite operations over good implementations with the commonly used compressed sparse row (CSR) format. We develop a performance model that allows us to correctly estimate the performance of our SpMM kernel implementations, and we identify cache bandwidth as a potential performance bottleneck beyond DRAM. We also analyze and optimize the performance of LOBPCG kernels (inner product and linear combinations on multiple vectors) and show up to 15× speedup over using high performance BLAS libraries for these operations. The resulting high performance LOBPCG solver achieves 1.4× to 1.8× speedup over the existing Lanczos solver on a series of CI computations on high-end multicore architectures (Intel Xeons). We also analyze the performance of our techniques on an Intel Xeon Phi Knights Corner (KNC) processor.« less

Axially deformed solution of the Skyrme-Hartree-Fock-Bogoliubov equations using the transformed harmonic oscillator basis (II) HFBTHO v2.00d: A new version of the program

NASA Astrophysics Data System (ADS)

Stoitsov, M. V.; Schunck, N.; Kortelainen, M.; Michel, N.; Nam, H.; Olsen, E.; Sarich, J.; Wild, S.

2013-06-01

We describe the new version 2.00d of the code HFBTHO that solves the nuclear Skyrme-Hartree-Fock (HF) or Skyrme-Hartree-Fock-Bogoliubov (HFB) problem by using the cylindrical transformed deformed harmonic oscillator basis. In the new version, we have implemented the following features: (i) the modified Broyden method for non-linear problems, (ii) optional breaking of reflection symmetry, (iii) calculation of axial multipole moments, (iv) finite temperature formalism for the HFB method, (v) linear constraint method based on the approximation of the Random Phase Approximation (RPA) matrix for multi-constraint calculations, (vi) blocking of quasi-particles in the Equal Filling Approximation (EFA), (vii) framework for generalized energy density with arbitrary density-dependences, and (viii) shared memory parallelism via OpenMP pragmas. Program summaryProgram title: HFBTHO v2.00d Catalog identifier: ADUI_v2_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADUI_v2_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GNU General Public License version 3 No. of lines in distributed program, including test data, etc.: 167228 No. of bytes in distributed program, including test data, etc.: 2672156 Distribution format: tar.gz Programming language: FORTRAN-95. Computer: Intel Pentium-III, Intel Xeon, AMD-Athlon, AMD-Opteron, Cray XT5, Cray XE6. Operating system: UNIX, LINUX, WindowsXP. RAM: 200 Mwords Word size: 8 bits Classification: 17.22. Does the new version supercede the previous version?: Yes Catalog identifier of previous version: ADUI_v1_0 Journal reference of previous version: Comput. Phys. Comm. 167 (2005) 43 Nature of problem: The solution of self-consistent mean-field equations for weakly-bound paired nuclei requires a correct description of the asymptotic properties of nuclear quasi-particle wave functions. In the present implementation, this is achieved by using the single-particle wave functions of the transformed harmonic oscillator, which allows for an accurate description of deformation effects and pairing correlations in nuclei arbitrarily close to the particle drip lines. Solution method: The program uses the axial Transformed Harmonic Oscillator (THO) single- particle basis to expand quasi-particle wave functions. It iteratively diagonalizes the Hartree-Fock-Bogoliubov Hamiltonian based on generalized Skyrme-like energy densities and zero-range pairing interactions until a self-consistent solution is found. A previous version of the program was presented in: M.V. Stoitsov, J. Dobaczewski, W. Nazarewicz, P. Ring, Comput. Phys. Commun. 167 (2005) 43-63. Reasons for new version: Version 2.00d of HFBTHO provides a number of new options such as the optional breaking of reflection symmetry, the calculation of axial multipole moments, the finite temperature formalism for the HFB method, optimized multi-constraint calculations, the treatment of odd-even and odd-odd nuclei in the blocking approximation, and the framework for generalized energy density with arbitrary density-dependences. It is also the first version of HFBTHO to contain threading capabilities. Summary of revisions: The modified Broyden method has been implemented, Optional breaking of reflection symmetry has been implemented, The calculation of all axial multipole moments up to λ=8 has been implemented, The finite temperature formalism for the HFB method has been implemented, The linear constraint method based on the approximation of the Random Phase Approximation (RPA) matrix for multi-constraint calculations has been implemented, The blocking of quasi-particles in the Equal Filling Approximation (EFA) has been implemented, The framework for generalized energy density functionals with arbitrary density-dependence has been implemented, Shared memory parallelism via OpenMP pragmas has been implemented. Restrictions: Axial- and time-reversal symmetries are assumed. Unusual features: The user must have access to the LAPACK subroutines DSYEVD, DSYTRF and DSYTRI, and their dependences, which compute eigenvalues and eigenfunctions of real symmetric matrices, the LAPACK subroutines DGETRI and DGETRF, which invert arbitrary real matrices, and the BLAS routines DCOPY, DSCAL, DGEMM and DGEMV for double-precision linear algebra (or provide another set of subroutines that can perform such tasks). The BLAS and LAPACK subroutines can be obtained from the Netlib Repository at the University of Tennessee, Knoxville: http://netlib2.cs.utk.edu/. Running time: Highly variable, as it depends on the nucleus, size of the basis, requested accuracy, requested configuration, compiler and libraries, and hardware architecture. An order of magnitude would be a few seconds for ground-state configurations in small bases N≈8-12, to a few minutes in very deformed configuration of a heavy nucleus with a large basis N>20.

Linearization: Students Forget the Operating Point

ERIC Educational Resources Information Center

Roubal, J.; Husek, P.; Stecha, J.

2010-01-01

Linearization is a standard part of modeling and control design theory for a class of nonlinear dynamical systems taught in basic undergraduate courses. Although linearization is a straight-line methodology, it is not applied correctly by many students since they often forget to keep the operating point in mind. This paper explains the topic and…

Perception of linear horizontal self-motion induced by peripheral vision /linearvection/ - Basic characteristics and visual-vestibular interactions

NASA Technical Reports Server (NTRS)

Berthoz, A.; Pavard, B.; Young, L. R.

1975-01-01

The basic characteristics of the sensation of linear horizontal motion have been studied. Objective linear motion was induced by means of a moving cart. Visually induced linear motion perception (linearvection) was obtained by projection of moving images at the periphery of the visual field. Image velocity and luminance thresholds for the appearance of linearvection have been measured and are in the range of those for image motion detection (without sensation of self motion) by the visual system. Latencies of onset are around 1 sec and short term adaptation has been shown. The dynamic range of the visual analyzer as judged by frequency analysis is lower than the vestibular analyzer. Conflicting situations in which visual cues contradict vestibular and other proprioceptive cues show, in the case of linearvection a dominance of vision which supports the idea of an essential although not independent role of vision in self motion perception.

Basic linear algebra subprograms for FORTRAN usage

NASA Technical Reports Server (NTRS)

Lawson, C. L.; Hanson, R. J.; Kincaid, D. R.; Krogh, F. T.

1977-01-01

A package of 38 low level subprograms for many of the basic operations of numerical linear algebra is presented. The package is intended to be used with FORTRAN. The operations in the package are dot products, elementary vector operations, Givens transformations, vector copy and swap, vector norms, vector scaling, and the indices of components of largest magnitude. The subprograms and a test driver are available in portable FORTRAN. Versions of the subprograms are also provided in assembly language for the IBM 360/67, the CDC 6600 and CDC 7600, and the Univac 1108.

The homopolar motor: A true relativistic engine

NASA Astrophysics Data System (ADS)

Guala-Valverde, Jorge; Mazzoni, Pedro; Achilles, Ricardo

2002-10-01

This article discusses experiments which enable the identification of the seat of mechanical forces in homopolar-machines reported earlier in this journal [J. Guala-Valverde and P. Mazzoni, Am. J. Phys. 63, 228-229 (1995); J. Guala-Valverde, P. Mazzoni, and K. Blas, ibid. 65, 147-148 (1997)]. We provide a suitable variation on a recent work "The Unipolar Dynamotor: A Genuine Relational Engine" [J. Guala-Valverde and P. Mazzoni, Apeiron 8, 41-52 (2001)], where "relational" implies "absolutely relativistic." Our view agrees with both Weber's recognition in the 19th century of the importance of relative motion in electromagnetic phenomena [A. K. T. Assis, Electrodynamics (Kluwer, Dordrecht, 1994)] and Einstein's 1905 statement concerning electromagnetism [Ann. Phys. 17, 891-921 (1905)].

Free electron lasers driven by linear induction accelerators: High power radiation sources

NASA Technical Reports Server (NTRS)

Orzechowski, T. J.

1989-01-01

The technology of Free Electron Lasers (FELs) and linear induction accelerators (LIAs) is addressed by outlining the following topics: fundamentals of FELs; basic concepts of linear induction accelerators; the Electron Laser Facility (a microwave FEL); PALADIN (an infrared FEL); magnetic switching; IMP; and future directions (relativistic klystrons). This presentation is represented by viewgraphs only.

Linear Ordinary Differential Equations with Constant Coefficients. Revisiting the Impulsive Response Method Using Factorization

ERIC Educational Resources Information Center

Camporesi, Roberto

2011-01-01

We present an approach to the impulsive response method for solving linear constant-coefficient ordinary differential equations based on the factorization of the differential operator. The approach is elementary, we only assume a basic knowledge of calculus and linear algebra. In particular, we avoid the use of distribution theory, as well as of…

Efficient linear algebra routines for symmetric matrices stored in packed form.

PubMed

Ahlrichs, Reinhart; Tsereteli, Kakha

2002-01-30

Quantum chemistry methods require various linear algebra routines for symmetric matrices, for example, diagonalization or Cholesky decomposition for positive matrices. We present a small set of these basic routines that are efficient and minimize memory requirements.

wannier90: A tool for obtaining maximally-localised Wannier functions

NASA Astrophysics Data System (ADS)

Mostofi, Arash A.; Yates, Jonathan R.; Lee, Young-Su; Souza, Ivo; Vanderbilt, David; Marzari, Nicola

2008-05-01

We present wannier90, a program for calculating maximally-localised Wannier functions (MLWF) from a set of Bloch energy bands that may or may not be attached to or mixed with other bands. The formalism works by minimising the total spread of the MLWF in real space. This is done in the space of unitary matrices that describe rotations of the Bloch bands at each k-point. As a result, wannier90 is independent of the basis set used in the underlying calculation to obtain the Bloch states. Therefore, it may be interfaced straightforwardly to any electronic structure code. The locality of MLWF can be exploited to compute band-structure, density of states and Fermi surfaces at modest computational cost. Furthermore, wannier90 is able to output MLWF for visualisation and other post-processing purposes. Wannier functions are already used in a wide variety of applications. These include analysis of chemical bonding in real space; calculation of dielectric properties via the modern theory of polarisation; and as an accurate and minimal basis set in the construction of model Hamiltonians for large-scale systems, in linear-scaling quantum Monte Carlo calculations, and for efficient computation of material properties, such as the anomalous Hall coefficient. wannier90 is freely available under the GNU General Public License from http://www.wannier.org/. Program summaryProgram title: wannier90 Catalogue identifier: AEAK_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEAK_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 556 495 No. of bytes in distributed program, including test data, etc.: 5 709 419 Distribution format: tar.gz Programming language: Fortran 90, perl Computer: any architecture with a Fortran 90 compiler Operating system: Linux, Windows, Solaris, AIX, Tru64 Unix, OSX RAM: 10 MB Word size: 32 or 64 Classification: 7.3 External routines:BLAS ( http://www/netlib.org/blas). LAPACK ( http://www.netlib.org/lapack). Both available under open-source licenses. Nature of problem: Obtaining maximally-localised Wannier functions from a set of Bloch energy bands that may or may not be entangled. Solution method: In the case of entangled bands, the optimally-connected subspace of interest is determined by minimising a functional which measures the subspace dispersion across the Brillouin zone. The maximally-localised Wannier functions within this subspace are obtained by subsequent minimisation of a functional that represents the total spread of the Wannier functions in real space. For the case of isolated energy bands only the second step of the procedure is required. Unusual features: Simple and user-friendly input system. Wannier functions and interpolated band structure output in a variety of file formats for visualisation. Running time: Test cases take 1 minute. References:N. Marzari, D. Vanderbilt, Maximally localized generalized Wannier functions for composite energy bands, Phys. Rev. B 56 (1997) 12847. I. Souza, N. Marzari, D. Vanderbilt, Maximally localized Wannier functions for entangled energy bands, Phys. Rev. B 65 (2001) 035109.

Unified control/structure design and modeling research

NASA Technical Reports Server (NTRS)

Mingori, D. L.; Gibson, J. S.; Blelloch, P. A.; Adamian, A.

1986-01-01

To demonstrate the applicability of the control theory for distributed systems to large flexible space structures, research was focused on a model of a space antenna which consists of a rigid hub, flexible ribs, and a mesh reflecting surface. The space antenna model used is discussed along with the finite element approximation of the distributed model. The basic control problem is to design an optimal or near-optimal compensator to suppress the linear vibrations and rigid-body displacements of the structure. The application of an infinite dimensional Linear Quadratic Gaussian (LQG) control theory to flexible structure is discussed. Two basic approaches for robustness enhancement were investigated: loop transfer recovery and sensitivity optimization. A third approach synthesized from elements of these two basic approaches is currently under development. The control driven finite element approximation of flexible structures is discussed. Three sets of finite element basic vectors for computing functional control gains are compared. The possibility of constructing a finite element scheme to approximate the infinite dimensional Hamiltonian system directly, instead of indirectly is discussed.

A Fresh Look at Linear Ordinary Differential Equations with Constant Coefficients. Revisiting the Impulsive Response Method Using Factorization

ERIC Educational Resources Information Center

Camporesi, Roberto

2016-01-01

We present an approach to the impulsive response method for solving linear constant-coefficient ordinary differential equations of any order based on the factorization of the differential operator. The approach is elementary, we only assume a basic knowledge of calculus and linear algebra. In particular, we avoid the use of distribution theory, as…

Lattice model of linear telechelic polymer melts. II. Influence of chain stiffness on basic thermodynamic properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Wen-Sheng, E-mail: wsxu@uchicago.edu; Freed, Karl F., E-mail: freed@uchicago.edu; Department of Chemistry, The University of Chicago, Chicago, Illinois 60637

2015-07-14

The lattice cluster theory (LCT) for semiflexible linear telechelic melts, developed in Paper I, is applied to examine the influence of chain stiffness on the average degree of self-assembly and the basic thermodynamic properties of linear telechelic polymer melts. Our calculations imply that chain stiffness promotes self-assembly of linear telechelic polymer melts that assemble on cooling when either polymer volume fraction ϕ or temperature T is high, but opposes self-assembly when both ϕ and T are sufficiently low. This allows us to identify a boundary line in the ϕ-T plane that separates two regions of qualitatively different influence of chainmore » stiffness on self-assembly. The enthalpy and entropy of self-assembly are usually treated as adjustable parameters in classical Flory-Huggins type theories for the equilibrium self-assembly of polymers, but they are demonstrated here to strongly depend on chain stiffness. Moreover, illustrative calculations for the dependence of the entropy density of linear telechelic polymer melts on chain stiffness demonstrate the importance of including semiflexibility within the LCT when exploring the nature of glass formation in models of linear telechelic polymer melts.« less

Studies with spike initiators - Linearization by noise allows continuous signal modulation in neural networks

NASA Technical Reports Server (NTRS)

Yu, Xiaolong; Lewis, Edwin R.

1989-01-01

It is shown that noise can be an important element in the translation of neuronal generator potentials (summed inputs) to neuronal spike trains (outputs), creating or expanding a range of amplitudes over which the spike rate is proportional to the generator potential amplitude. Noise converts the basically nonlinear operation of a spike initiator into a nearly linear modulation process. This linearization effect of noise is examined in a simple intuitive model of a static threshold and in a more realistic computer simulation of spike initiator based on the Hodgkin-Huxley (HH) model. The results are qualitatively similar; in each case larger noise amplitude results in a larger range of nearly linear modulation. The computer simulation of the HH model with noise shows linear and nonlinear features that were earlier observed in spike data obtained from the VIIIth nerve of the bullfrog. This suggests that these features can be explained in terms of spike initiator properties, and it also suggests that the HH model may be useful for representing basic spike initiator properties in vertebrates.

On the Feasibility of a Generalized Linear Program

DTIC Science & Technology

1989-03-01

generealized linear program by applying the same algorithm to a "phase-one" problem without requiring that the initial basic feasible solution to the latter be non-degenerate. secUrMTY C.AMlIS CAYI S OP ?- PAeES( UII -W & ,

Applications of Goal Programming to Education.

ERIC Educational Resources Information Center

Van Dusseldorp, Ralph A.; And Others

This paper discusses goal programming, a computer-based operations research technique that is basically a modification and extension of linear programming. The authors first discuss the similarities and differences between goal programming and linear programming, then describe the limitations of goal programming and its possible applications for…

Basic Applied Mathematics Part 1.

ERIC Educational Resources Information Center

New York City Board of Education, Brooklyn, NY. Div. of Curriculum and Instruction.

This guide, published by the New York City Board of Education, presents 62 lesson plans in basic mathematics for tenth grade students. Lesson plans and performance objectives focus on the following areas: (1) fundamental operations with signed numbers; (2) linear, weight and temperature measurements; (3) fractions, decimals and percents; (4)…

Hurricane Patricia Viewed by NASA ISS-RapidScat

NASA Image and Video Library

2015-10-23

NASA's ISS-RapidScat passed over Hurricane Patricia at about 3:00 AM GMT on Oct. 23, 2015. A Hurricane Warning was in effect from San Blas to Punta San Telmo. A Hurricane Watch was in effect from east of Punta San Telmo to Lazaro Cardenas and a Tropical Storm Warning was in effect from east of Punta San Telmo to Lazaro Cardenas. Patricia was moving toward the north-northwest near 12 mph (19 kph) and a turn toward the north is expected later this morning, followed by a turn toward the north-northeast this afternoon. On the forecast track, the core of Patricia will make landfall in the hurricane warning area today, Oct. 23, 2015, during the afternoon or evening. http://photojournal.jpl.nasa.gov/catalog/PIA20031

A higher order panel method for linearized supersonic flow

NASA Technical Reports Server (NTRS)

Ehlers, F. E.; Epton, M. A.; Johnson, F. T.; Magnus, A. E.; Rubbert, P. E.

1979-01-01

The basic integral equations of linearized supersonic theory for an advanced supersonic panel method are derived. Methods using only linear varying source strength over each panel or only quadratic doublet strength over each panel gave good agreement with analytic solutions over cones and zero thickness cambered wings. For three dimensional bodies and wings of general shape, combined source and doublet panels with interior boundary conditions to eliminate the internal perturbations lead to a stable method providing good agreement experiment. A panel system with all edges contiguous resulted from dividing the basic four point non-planar panel into eight triangular subpanels, and the doublet strength was made continuous at all edges by a quadratic distribution over each subpanel. Superinclined panels were developed and tested on s simple nacelle and on an airplane model having engine inlets, with excellent results.

Computing the Density Matrix in Electronic Structure Theory on Graphics Processing Units.

PubMed

Cawkwell, M J; Sanville, E J; Mniszewski, S M; Niklasson, Anders M N

2012-11-13

The self-consistent solution of a Schrödinger-like equation for the density matrix is a critical and computationally demanding step in quantum-based models of interatomic bonding. This step was tackled historically via the diagonalization of the Hamiltonian. We have investigated the performance and accuracy of the second-order spectral projection (SP2) algorithm for the computation of the density matrix via a recursive expansion of the Fermi operator in a series of generalized matrix-matrix multiplications. We demonstrate that owing to its simplicity, the SP2 algorithm [Niklasson, A. M. N. Phys. Rev. B2002, 66, 155115] is exceptionally well suited to implementation on graphics processing units (GPUs). The performance in double and single precision arithmetic of a hybrid GPU/central processing unit (CPU) and full GPU implementation of the SP2 algorithm exceed those of a CPU-only implementation of the SP2 algorithm and traditional matrix diagonalization when the dimensions of the matrices exceed about 2000 × 2000. Padding schemes for arrays allocated in the GPU memory that optimize the performance of the CUBLAS implementations of the level 3 BLAS DGEMM and SGEMM subroutines for generalized matrix-matrix multiplications are described in detail. The analysis of the relative performance of the hybrid CPU/GPU and full GPU implementations indicate that the transfer of arrays between the GPU and CPU constitutes only a small fraction of the total computation time. The errors measured in the self-consistent density matrices computed using the SP2 algorithm are generally smaller than those measured in matrices computed via diagonalization. Furthermore, the errors in the density matrices computed using the SP2 algorithm do not exhibit any dependence of system size, whereas the errors increase linearly with the number of orbitals when diagonalization is employed.

Mathematical Modelling in Engineering: A Proposal to Introduce Linear Algebra Concepts

ERIC Educational Resources Information Center

Cárcamo Bahamonde, Andrea; Gómez Urgelles, Joan; Fortuny Aymemí, Josep

2016-01-01

The modern dynamic world requires that basic science courses for engineering, including linear algebra, emphasise the development of mathematical abilities primarily associated with modelling and interpreting, which are not exclusively calculus abilities. Considering this, an instructional design was created based on mathematical modelling and…

Linear-stability theory of thermocapillary convection in a model of float-zone crystal growth

NASA Technical Reports Server (NTRS)

Neitzel, G. P.; Chang, K.-T.; Jankowski, D. F.; Mittelmann, H. D.

1992-01-01

Linear-stability theory has been applied to a basic state of thermocapillary convection in a model half-zone to determine values of the Marangoni number above which instability is guaranteed. The basic state must be determined numerically since the half-zone is of finite, O(1) aspect ratio with two-dimensional flow and temperature fields. This, in turn, means that the governing equations for disturbance quantities will remain partial differential equations. The disturbance equations are treated by a staggered-grid discretization scheme. Results are presented for a variety of parameters of interest in the problem, including both terrestrial and microgravity cases.

Applying the Principles of Specific Objectivity and of Generalizability to the Measurement of Change.

ERIC Educational Resources Information Center

Fischer, Gerhard H.

1987-01-01

A natural parameterization and formalization of the problem of measuring change in dichotomous data is developed. Mathematically-exact definitions of specific objectivity are presented, and the basic structures of the linear logistic test model and the linear logistic model with relaxed assumptions are clarified. (SLD)

Getting a Bead on It

ERIC Educational Resources Information Center

Ferrucci, Beverly J.; McDougall, Jennifer; Carter, Jack

2009-01-01

One challenge that middle school teachers commonly face is finding insightful, hands-on applications when teaching basic mathematical concepts. One concept that is a foundation of middle school mathematics is the notion of "linear functions." Although a variety of models can be used for linear equations, such as temperature conversions,…

Winning in Time: Enabling Naturalistic Decision Making in Command and Control

DTIC Science & Technology

2000-11-01

non-linear with non-linearity defined as a condition master chess player , the NBA basketball player , the in which a system disobeys principles of great...are made up of basic others identified in the successive sectors, are feedback structures which have known behavioral points of leverage for policy

Mathematical Modelling in Engineering: An Alternative Way to Teach Linear Algebra

ERIC Educational Resources Information Center

Domínguez-García, S.; García-Planas, M. I.; Taberna, J.

2016-01-01

Technological advances require that basic science courses for engineering, including Linear Algebra, emphasize the development of mathematical strengths associated with modelling and interpretation of results, which are not limited only to calculus abilities. Based on this consideration, we have proposed a project-based learning, giving a dynamic…

Number Games, Magnitude Representation, and Basic Number Skills in Preschoolers

ERIC Educational Resources Information Center

Whyte, Jemma Catherine; Bull, Rebecca

2008-01-01

The effect of 3 intervention board games (linear number, linear color, and nonlinear number) on young children's (mean age = 3.8 years) counting abilities, number naming, magnitude comprehension, accuracy in number-to-position estimation tasks, and best-fit numerical magnitude representations was examined. Pre- and posttest performance was…

Linear ordinary differential equations with constant coefficients. Revisiting the impulsive response method using factorization

NASA Astrophysics Data System (ADS)

Camporesi, Roberto

2011-06-01

We present an approach to the impulsive response method for solving linear constant-coefficient ordinary differential equations based on the factorization of the differential operator. The approach is elementary, we only assume a basic knowledge of calculus and linear algebra. In particular, we avoid the use of distribution theory, as well as of the other more advanced approaches: Laplace transform, linear systems, the general theory of linear equations with variable coefficients and the variation of constants method. The approach presented here can be used in a first course on differential equations for science and engineering majors.

Biomotor structures in elite female handball players.

PubMed

Katić, Ratko; Cavala, Marijana; Srhoj, Vatromir

2007-09-01

In order to identify biomotor structures in elite female handball players, factor structures of morphological characteristics and basic motor abilities of elite female handball players (N = 53) were determined first, followed by determination of relations between the morphological-motor space factors obtained and the set of criterion variables evaluating situation motor abilities in handball. Factor analysis of 14 morphological measures produced three morphological factors, i.e. factor of absolute voluminosity (mesoendomorph), factor of longitudinal skeleton dimensionality, and factor of transverse hand dimensionality. Factor analysis of 15 motor variables yielded five basic motor dimensions, i.e. factor of agility, factor of jumping explosive strength, factor of throwing explosive strength, factor of movement frequency rate, and factor of running explosive strength (sprint). Four significant canonic correlations, i.e. linear combinations, explained the correlation between the set of eight latent variables of the morphological and basic motor space and five variables of situation motoricity. First canonic linear combination is based on the positive effect of the factors of agility/coordination on the ability of fast movement without ball. Second linear combination is based on the effect of jumping explosive strength and transverse hand dimensionality on ball manipulation, throw precision, and speed of movement with ball. Third linear combination is based on the running explosive strength determination by the speed of movement with ball, whereas fourth combination is determined by throwing and jumping explosive strength, and agility on ball pass. The results obtained were consistent with the model of selection in female handball proposed (Srhoj et al., 2006), showing the speed of movement without ball and the ability of ball manipulation to be the predominant specific abilities, as indicated by the first and second linear combination.

Optimal Facility Location Tool for Logistics Battle Command (LBC)

DTIC Science & Technology

2015-08-01

64 Appendix B. VBA Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72 Appendix C. Story...should city planners have located emergency service facilities so that all households (the demand) had equal access to coverage?” The critical...programming language called Visual Basic for Applications ( VBA ). CPLEX is a commercial solver for linear, integer, and mixed integer linear programming problems

''Math in a Can'': Teaching Mathematics and Engineering Design

ERIC Educational Resources Information Center

Narode, Ronald B.

2011-01-01

Using an apparently simple problem, ''Design a cylindrical can that will hold a liter of milk,'' this paper demonstrates how engineering design may facilitate the teaching of the following ideas to secondary students: linear and non-linear relationships; basic geometry of circles, rectangles, and cylinders; unit measures of area and volume;…

Commentary on A General Curriculum in Mathematics for Colleges.

ERIC Educational Resources Information Center

Committee on the Undergraduate Program in Mathematics, Berkeley, CA.

This document constitutes a complete revision of the report of the same name first published in 1965. A new list of basic courses is described, consisting of Calculus I, Calculus II, Elementary Linear Algebra, Multivariable Calculus I, Linear Algebra, and Introductory Modern Algebra. Commentaries outline the content and spirit of these courses in…

Age, Sex, and Body Composition as Predictors of Children's Performance on Basic Motor Abilities and Health-Related Fitness Items.

ERIC Educational Resources Information Center

Pissanos, Becky W.; And Others

1983-01-01

Step-wise linear regressions were used to relate children's age, sex, and body composition to performance on basic motor abilities including balance, speed, agility, power, coordination, and reaction time, and to health-related fitness items including flexibility, muscle strength and endurance and cardiovascular functions. Eighty subjects were in…

Distributed-Memory Fast Maximal Independent Set

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kanewala Appuhamilage, Thejaka Amila J.; Zalewski, Marcin J.; Lumsdaine, Andrew

The Maximal Independent Set (MIS) graph problem arises in many applications such as computer vision, information theory, molecular biology, and process scheduling. The growing scale of MIS problems suggests the use of distributed-memory hardware as a cost-effective approach to providing necessary compute and memory resources. Luby proposed four randomized algorithms to solve the MIS problem. All those algorithms are designed focusing on shared-memory machines and are analyzed using the PRAM model. These algorithms do not have direct efficient distributed-memory implementations. In this paper, we extend two of Luby’s seminal MIS algorithms, “Luby(A)” and “Luby(B),” to distributed-memory execution, and we evaluatemore » their performance. We compare our results with the “Filtered MIS” implementation in the Combinatorial BLAS library for two types of synthetic graph inputs.« less

The UPSF code: a metaprogramming-based high-performance automatically parallelized plasma simulation framework

NASA Astrophysics Data System (ADS)

Gao, Xiatian; Wang, Xiaogang; Jiang, Binhao

2017-10-01

UPSF (Universal Plasma Simulation Framework) is a new plasma simulation code designed for maximum flexibility by using edge-cutting techniques supported by C++17 standard. Through use of metaprogramming technique, UPSF provides arbitrary dimensional data structures and methods to support various kinds of plasma simulation models, like, Vlasov, particle in cell (PIC), fluid, Fokker-Planck, and their variants and hybrid methods. Through C++ metaprogramming technique, a single code can be used to arbitrary dimensional systems with no loss of performance. UPSF can also automatically parallelize the distributed data structure and accelerate matrix and tensor operations by BLAS. A three-dimensional particle in cell code is developed based on UPSF. Two test cases, Landau damping and Weibel instability for electrostatic and electromagnetic situation respectively, are presented to show the validation and performance of the UPSF code.

Manufacturing Methods and Technology Project Execution Report

DTIC Science & Technology

1981-08-01

DISTRIBUTED. 77 3183 IMPROVED PROCESSES FOR INERTIAL GRADE Q-FLEX ACCELERDMETER SuNSTRAND IMPROVED ACCELEROMETER blAS STABILITY, BY THICKENING GOLD ...O h- ^O UJ —« X -H 1— —i 0 □ LU UO U. 1-0 < a. O 3 LU <£ LU O a LU LO C 0 0 LU O < etf <t X) 1/1 ^ O + ^JJ 3 <I to cL • r-J 3 ■L. LU a: a ^ z < 0...x 2 X O Etf a: >- • Q- aC Q_ ct Q- at :£ ^ Q -^ Ct a C^ £ UJ at J at ac UJ J a a kU a. m —" < X ci; _J ac LU Wl i— O ^- —) <o "O i/J to Ml LU if! O

Using a multifrontal sparse solver in a high performance, finite element code

NASA Technical Reports Server (NTRS)

King, Scott D.; Lucas, Robert; Raefsky, Arthur

1990-01-01

We consider the performance of the finite element method on a vector supercomputer. The computationally intensive parts of the finite element method are typically the individual element forms and the solution of the global stiffness matrix both of which are vectorized in high performance codes. To further increase throughput, new algorithms are needed. We compare a multifrontal sparse solver to a traditional skyline solver in a finite element code on a vector supercomputer. The multifrontal solver uses the Multiple-Minimum Degree reordering heuristic to reduce the number of operations required to factor a sparse matrix and full matrix computational kernels (e.g., BLAS3) to enhance vector performance. The net result in an order-of-magnitude reduction in run time for a finite element application on one processor of a Cray X-MP.

Basic Research in the Mathematical Foundations of Stability Theory, Control Theory and Numerical Linear Algebra.

DTIC Science & Technology

1979-09-01

without determinantal divisors, Linear and Multilinear Algebra 7(1979), 107-109. 4. The use of integral operators in number theory (with C. Ryavec and...Gersgorin revisited, to appear in Letters in Linear Algebra. 15. A surprising determinantal inequality for real matrices (with C.R. Johnson), to appear in...Analysis: An Essay Concerning the Limitations of Some Mathematical Methods in the Social , Political and Biological Sciences, David Berlinski, MIT Press

Aircraft Airframe Cost Estimation Using a Random Coefficients Model

DTIC Science & Technology

1979-12-01

approach will also be used here. 2 Model Formulation Several different types of equations could be used for the basic form of the CER, such as linear ...5) Marcotte developed several CER’s for fighter aircraft airframes using the log- linear model . A plot of the residuals from the CER for recurring...of the natural logarithm. Ordinary Least Squares The ordinary least squares procedure starts with the equation for the general linear model . The

A fresh look at linear ordinary differential equations with constant coefficients. Revisiting the impulsive response method using factorization

NASA Astrophysics Data System (ADS)

Camporesi, Roberto

2016-01-01

We present an approach to the impulsive response method for solving linear constant-coefficient ordinary differential equations of any order based on the factorization of the differential operator. The approach is elementary, we only assume a basic knowledge of calculus and linear algebra. In particular, we avoid the use of distribution theory, as well as of the other more advanced approaches: Laplace transform, linear systems, the general theory of linear equations with variable coefficients and variation of parameters. The approach presented here can be used in a first course on differential equations for science and engineering majors.

The linear sizes tolerances and fits system modernization

NASA Astrophysics Data System (ADS)

Glukhov, V. I.; Grinevich, V. A.; Shalay, V. V.

2018-04-01

The study is carried out on the urgent topic for technical products quality providing in the tolerancing process of the component parts. The aim of the paper is to develop alternatives for improving the system linear sizes tolerances and dimensional fits in the international standard ISO 286-1. The tasks of the work are, firstly, to classify as linear sizes the elements additionally linear coordinating sizes that determine the detail elements location and, secondly, to justify the basic deviation of the tolerance interval for the element's linear size. The geometrical modeling method of real details elements, the analytical and experimental methods are used in the research. It is shown that the linear coordinates are the dimensional basis of the elements linear sizes. To standardize the accuracy of linear coordinating sizes in all accuracy classes, it is sufficient to select in the standardized tolerance system only one tolerance interval with symmetrical deviations: Js for internal dimensional elements (holes) and js for external elements (shafts). The main deviation of this coordinating tolerance is the average zero deviation, which coincides with the nominal value of the coordinating size. Other intervals of the tolerance system are remained for normalizing the accuracy of the elements linear sizes with a fundamental change in the basic deviation of all tolerance intervals is the maximum deviation corresponding to the limit of the element material: EI is the lower tolerance for the of the internal elements (holes) sizes and es is the upper tolerance deviation for the outer elements (shafts) sizes. It is the sizes of the material maximum that are involved in the of the dimensional elements mating of the shafts and holes and determine the fits type.

Unit Cohesion and the Surface Navy: Does Cohesion Affect Performance

DTIC Science & Technology

1989-12-01

v. 68, 1968. Neter, J., Wasserman, W., and Kutner, M. H., Applied Linear Regression Models, 2d ed., Boston, MA: Irwin, 1989. Rand Corporation R-2607...Neter, J., Wasserman, W., and Kutner, M. H., Applied Linear Regression Models, 2d ed., Boston, MA: Irwin, 1989. SAS User’s Guide: Basics, Version 5 ed

A Comparison Study between a Traditional and Experimental Program.

ERIC Educational Resources Information Center

Dogan, Hamide

This paper is part of a dissertation defended in January 2001 as part of the author's Ph.D. requirement. The study investigated the effects of use of Mathematica, a computer algebra system, in learning basic linear algebra concepts, It was done by means of comparing two first year linear algebra classes, one traditional and one Mathematica…

The Dependence of the Spring Constant in the Linear Range on Spring Parameters

ERIC Educational Resources Information Center

Khotimah, Siti Nurul; Viridi, Sparisoma; Widayani; Khairurrijal

2011-01-01

In basic physics laboratories, springs are normally used to determine both spring constants and the Earth's gravitational acceleration. Students generally do not notice that the spring constant is not a universal constant, but depends on the spring parameters. This paper shows and verifies that the spring constant in the linear range is inversely…

A Vernacular for Linear Latent Growth Models

ERIC Educational Resources Information Center

Hancock, Gregory R.; Choi, Jaehwa

2006-01-01

In its most basic form, latent growth modeling (latent curve analysis) allows an assessment of individuals' change in a measured variable X over time. For simple linear models, as with other growth models, parameter estimates associated with the a construct (amount of X at a chosen temporal reference point) and b construct (growth in X per unit…

Linear circuit analysis program for IBM 1620 Monitor 2, 1311/1443 data processing system /CIRCS/

NASA Technical Reports Server (NTRS)

Hatfield, J.

1967-01-01

CIRCS is modification of IBSNAP Circuit Analysis Program, for use on smaller systems. This data processing system retains the basic dc, transient analysis, and FORTRAN 2 formats. It can be used on the IBM 1620/1311 Monitor I Mod 5 system, and solves a linear network containing 15 nodes and 45 branches.

General purpose computer programs for numerically analyzing linear ac electrical and electronic circuits for steady-state conditions

NASA Technical Reports Server (NTRS)

Egebrecht, R. A.; Thorbjornsen, A. R.

1967-01-01

Digital computer programs determine steady-state performance characteristics of active and passive linear circuits. The ac analysis program solves the basic circuit parameters. The compiler program solves these circuit parameters and in addition provides a more versatile program by allowing the user to perform mathematical and logical operations.

SPAR thermal analysis processors reference manual, system level 16. Volume 1: Program executive. Volume 2: Theory. Volume 3: Demonstration problems. Volume 4: Experimental thermal element capability. Volume 5: Programmer reference

NASA Technical Reports Server (NTRS)

Marlowe, M. B.; Moore, R. A.; Whetstone, W. D.

1979-01-01

User instructions are given for performing linear and nonlinear steady state and transient thermal analyses with SPAR thermal analysis processors TGEO, SSTA, and TRTA. It is assumed that the user is familiar with basic SPAR operations and basic heat transfer theory.

Determination of the n-octanol/water partition coefficients of weakly ionizable basic compounds by reversed-phase high-performance liquid chromatography with neutral model compounds.

PubMed

Liang, Chao; Han, Shu-ying; Qiao, Jun-qin; Lian, Hong-zhen; Ge, Xin

2014-11-01

A strategy to utilize neutral model compounds for lipophilicity measurement of ionizable basic compounds by reversed-phase high-performance liquid chromatography is proposed in this paper. The applicability of the novel protocol was justified by theoretical derivation. Meanwhile, the linear relationships between logarithm of apparent n-octanol/water partition coefficients (logKow '') and logarithm of retention factors corresponding to the 100% aqueous fraction of mobile phase (logkw ) were established for a basic training set, a neutral training set and a mixed training set of these two. As proved in theory, the good linearity and external validation results indicated that the logKow ''-logkw relationships obtained from a neutral model training set were always reliable regardless of mobile phase pH. Afterwards, the above relationships were adopted to determine the logKow of harmaline, a weakly dissociable alkaloid. As far as we know, this is the first report on experimental logKow data for harmaline (logKow = 2.28 ± 0.08). Introducing neutral compounds into a basic model training set or using neutral model compounds alone is recommended to measure the lipophilicity of weakly ionizable basic compounds especially those with high hydrophobicity for the advantages of more suitable model compound choices and convenient mobile phase pH control. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Propagation of uncertainty by Monte Carlo simulations in case of basic geodetic computations

NASA Astrophysics Data System (ADS)

Wyszkowska, Patrycja

2017-12-01

The determination of the accuracy of functions of measured or adjusted values may be a problem in geodetic computations. The general law of covariance propagation or in case of the uncorrelated observations the propagation of variance (or the Gaussian formula) are commonly used for that purpose. That approach is theoretically justified for the linear functions. In case of the non-linear functions, the first-order Taylor series expansion is usually used but that solution is affected by the expansion error. The aim of the study is to determine the applicability of the general variance propagation law in case of the non-linear functions used in basic geodetic computations. The paper presents errors which are a result of negligence of the higher-order expressions and it determines the range of such simplification. The basis of that analysis is the comparison of the results obtained by the law of propagation of variance and the probabilistic approach, namely Monte Carlo simulations. Both methods are used to determine the accuracy of the following geodetic computations: the Cartesian coordinates of unknown point in the three-point resection problem, azimuths and distances of the Cartesian coordinates, height differences in the trigonometric and the geometric levelling. These simulations and the analysis of the results confirm the possibility of applying the general law of variance propagation in basic geodetic computations even if the functions are non-linear. The only condition is the accuracy of observations, which cannot be too low. Generally, this is not a problem with using present geodetic instruments.

Linear analysis of a force reflective teleoperator

NASA Technical Reports Server (NTRS)

Biggers, Klaus B.; Jacobsen, Stephen C.; Davis, Clark C.

1989-01-01

Complex force reflective teleoperation systems are often very difficult to analyze due to the large number of components and control loops involved. One mode of a force reflective teleoperator is described. An analysis of the performance of the system based on a linear analysis of the general full order model is presented. Reduced order models are derived and correlated with the full order models. Basic effects of force feedback and position feedback are examined and the effects of time delays between the master and slave are studied. The results show that with symmetrical position-position control of teleoperators, a basic trade off must be made between the intersystem stiffness of the teleoperator, and the impedance felt by the operator in free space.

Tangent linear super-parameterization: attributable, decomposable moist processes for tropical variability studies

NASA Astrophysics Data System (ADS)

Mapes, B. E.; Kelly, P.; Song, S.; Hu, I. K.; Kuang, Z.

2015-12-01

An economical 10-layer global primitive equation solver is driven by time-independent forcing terms, derived from a training process, to produce a realisting eddying basic state with a tracer q trained to act like water vapor mixing ratio. Within this basic state, linearized anomaly moist physics in the column are applied in the form of a 20x20 matrix. The control matrix was derived from the results of Kuang (2010, 2012) who fitted a linear response function from a cloud resolving model in a state of deep convecting equilibrium. By editing this matrix in physical space and eigenspace, scaling and clipping its action, and optionally adding terms for processes that do not conserve moist statice energy (radiation, surface fluxes), we can decompose and explain the model's diverse moist process coupled variability. Recitified effects of this variability on the general circulation and climate, even in strictly zero-mean centered anomaly physic cases, also are sometimes surprising.

Quantum computation for solving linear systems

NASA Astrophysics Data System (ADS)

Cao, Yudong

Quantum computation is a subject born out of the combination between physics and computer science. It studies how the laws of quantum mechanics can be exploited to perform computations much more efficiently than current computers (termed classical computers as oppose to quantum computers). The thesis starts by introducing ideas from quantum physics and theoretical computer science and based on these ideas, introducing the basic concepts in quantum computing. These introductory discussions are intended for non-specialists to obtain the essential knowledge needed for understanding the new results presented in the subsequent chapters. After introducing the basics of quantum computing, we focus on the recently proposed quantum algorithm for linear systems. The new results include i) special instances of quantum circuits that can be implemented using current experimental resources; ii) detailed quantum algorithms that are suitable for a broader class of linear systems. We show that for some particular problems the quantum algorithm is able to achieve exponential speedup over their classical counterparts.

Stability analysis of confined V-shaped flames in high-velocity streams.

PubMed

El-Rabii, Hazem; Joulin, Guy; Kazakov, Kirill A

2010-06-01

The problem of linear stability of confined V-shaped flames with arbitrary gas expansion is addressed. Using the on-shell description of flame dynamics, a general equation governing propagation of disturbances of an anchored flame is obtained. This equation is solved analytically for V-flames anchored in high-velocity channel streams. It is demonstrated that dynamics of the flame disturbances in this case is controlled by the memory effects associated with vorticity generated by the perturbed flame. The perturbation growth rate spectrum is determined, and explicit analytical expressions for the eigenfunctions are given. It is found that the piecewise linear V structure is unstable for all values of the gas expansion coefficient. Despite the linearity of the basic pattern, however, evolutions of the V-flame disturbances are completely different from those found for freely propagating planar flames or open anchored flames. The obtained results reveal strong influence of the basic flow and the channel walls on the stability properties of confined V-flames.

Geobiology in the Lab

NASA Astrophysics Data System (ADS)

José López-Galindo, María

2017-04-01

Geobiology is, nowadays, one of the most important lines of research of USGS. It is the interdisciplinary study of the interactions of microorganisms and earth materials (including soil, sediment, the atmosphere, the hydrosphere, minerals, and rocks) (U.S. Geological Survey, 2007). A study about geobiolgical interactions between microorganisms and felsic rock surfaces was carried out in San Blas Secondary School with students, aged 16-17, as an enforcement of a part of this abstract author's thesis work, and developed in the Coruña University. The activity took place in the school laboratory as a complement of the theoretical Spanish curriculum about living things. After visiting a granitic area, near the famous Rio Tinto mining district, students collected different rock samples. They learned about bioweathering on igneous rocks, and how microorganisms can play an essential double role on rock surface: dissolution and mineral deposition. These organisms, living in hard and basic environments, are considered extremophiles (López-Galindo, 2013) which is an important translatable concept to the life beyond the Earth. Afterwards, students had the opportunity to grow these microorganisms under different conditions and examine them through a scholar microscope, comparing these images with SEM ones, taken in Central Services of Research Building in the Coruña University, to determine genus and species, when it was possible. An opportunity to study rare living things, an introduction to geobiology, hostile environments and different physical and chemical conditions out of Earth is hereafter offered, through these simple experiences, to other secondary teachers in the world. U.S. Geological Survey, 2007, Facing tomorrow's challenges—U.S. Geological Survey science in the decade 2007-2017: U.S. Geological Survey Circular 1309, x + 70 p. López-Galindo, M.J. 2013, Bioweathering in Igneous Rocks. Siliceous Speleothems from a Geobiological Viewpoint. Doctoral Dissertation. Coruña University. 323 pp. http://hdl.handle.net/2183/11581.

Linear solvation energy relationships. Solvent effects on the fluorescence of thiabendazole homologues

NASA Astrophysics Data System (ADS)

Tway, Patricia C.; Cline Love, L. J.

1982-03-01

The solvatochromic equations describing the effects of solvent polarity/polarizability (π*), solvent hydrogen bond donor acidity (α), and solvent hydrogen bond acceptor basicity (β) have been determined for several thiabendazole homologues. The s coefficient was found to be linearly related to the Hammett σ + values, and can be used as a measure of substituent effects on the lumiphor.

The Impact of Model Misspecification on Parameter Estimation and Item-Fit Assessment in Log-Linear Diagnostic Classification Models

ERIC Educational Resources Information Center

Kunina-Habenicht, Olga; Rupp, Andre A.; Wilhelm, Oliver

2012-01-01

Using a complex simulation study we investigated parameter recovery, classification accuracy, and performance of two item-fit statistics for correct and misspecified diagnostic classification models within a log-linear modeling framework. The basic manipulated test design factors included the number of respondents (1,000 vs. 10,000), attributes (3…

BCYCLIC: A parallel block tridiagonal matrix cyclic solver

NASA Astrophysics Data System (ADS)

Hirshman, S. P.; Perumalla, K. S.; Lynch, V. E.; Sanchez, R.

2010-09-01

A block tridiagonal matrix is factored with minimal fill-in using a cyclic reduction algorithm that is easily parallelized. Storage of the factored blocks allows the application of the inverse to multiple right-hand sides which may not be known at factorization time. Scalability with the number of block rows is achieved with cyclic reduction, while scalability with the block size is achieved using multithreaded routines (OpenMP, GotoBLAS) for block matrix manipulation. This dual scalability is a noteworthy feature of this new solver, as well as its ability to efficiently handle arbitrary (non-powers-of-2) block row and processor numbers. Comparison with a state-of-the art parallel sparse solver is presented. It is expected that this new solver will allow many physical applications to optimally use the parallel resources on current supercomputers. Example usage of the solver in magneto-hydrodynamic (MHD), three-dimensional equilibrium solvers for high-temperature fusion plasmas is cited.

Optimizing Excited-State Electronic-Structure Codes for Intel Knights Landing: A Case Study on the BerkeleyGW Software

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deslippe, Jack; da Jornada, Felipe H.; Vigil-Fowler, Derek

2016-10-06

We profile and optimize calculations performed with the BerkeleyGW code on the Xeon-Phi architecture. BerkeleyGW depends both on hand-tuned critical kernels as well as on BLAS and FFT libraries. We describe the optimization process and performance improvements achieved. We discuss a layered parallelization strategy to take advantage of vector, thread and node-level parallelism. We discuss locality changes (including the consequence of the lack of L3 cache) and effective use of the on-package high-bandwidth memory. We show preliminary results on Knights-Landing including a roofline study of code performance before and after a number of optimizations. We find that the GW methodmore » is particularly well-suited for many-core architectures due to the ability to exploit a large amount of parallelism over plane-wave components, band-pairs, and frequencies.« less

Anomaly General Circulation Models.

NASA Astrophysics Data System (ADS)

Navarra, Antonio

The feasibility of the anomaly model is assessed using barotropic and baroclinic models. In the barotropic case, both a stationary and a time-dependent model has been formulated and constructed, whereas only the stationary, linear case is considered in the baroclinic case. Results from the barotropic model indicate that a relation between the stationary solution and the time-averaged non-linear solution exists. The stationary linear baroclinic solution can therefore be considered with some confidence. The linear baroclinic anomaly model poses a formidable mathematical problem because it is necessary to solve a gigantic linear system to obtain the solution. A new method to find solution of large linear system, based on a projection on the Krylov subspace is shown to be successful when applied to the linearized baroclinic anomaly model. The scheme consists of projecting the original linear system on the Krylov subspace, thereby reducing the dimensionality of the matrix to be inverted to obtain the solution. With an appropriate setting of the damping parameters, the iterative Krylov method reaches a solution even using a Krylov subspace ten times smaller than the original space of the problem. This generality allows the treatment of the important problem of linear waves in the atmosphere. A larger class (nonzonally symmetric) of basic states can now be treated for the baroclinic primitive equations. These problem leads to large unsymmetrical linear systems of order 10000 and more which can now be successfully tackled by the Krylov method. The (R7) linear anomaly model is used to investigate extensively the linear response to equatorial and mid-latitude prescribed heating. The results indicate that the solution is deeply affected by the presence of the stationary waves in the basic state. The instability of the asymmetric flows, first pointed out by Simmons et al. (1983), is active also in the baroclinic case. However, the presence of baroclinic processes modifies the dominant response. The most sensitive areas are identified; they correspond to north Japan, the Pole and Greenland regions. A limited set of higher resolution (R15) experiments indicate that this situation is still present and enhanced at higher resolution. The linear anomaly model is also applied to a realistic case. (Abstract shortened with permission of author.).

A model of the human in a cognitive prediction task.

NASA Technical Reports Server (NTRS)

Rouse, W. B.

1973-01-01

The human decision maker's behavior when predicting future states of discrete linear dynamic systems driven by zero-mean Gaussian processes is modeled. The task is on a slow enough time scale that physiological constraints are insignificant compared with cognitive limitations. The model is basically a linear regression system identifier with a limited memory and noisy observations. Experimental data are presented and compared to the model.

Semigroup theory and numerical approximation for equations in linear viscoelasticity

NASA Technical Reports Server (NTRS)

Fabiano, R. H.; Ito, K.

1990-01-01

A class of abstract integrodifferential equations used to model linear viscoelastic beams is investigated analytically, applying a Hilbert-space approach. The basic equation is rewritten as a Cauchy problem, and its well-posedness is demonstrated. Finite-dimensional subspaces of the state space and an estimate of the state operator are obtained; approximation schemes for the equations are constructed; and the convergence is proved using the Trotter-Kato theorem of linear semigroup theory. The actual convergence behavior of different approximations is demonstrated in numerical computations, and the results are presented in tables.

Quantitative structure-retention relationship studies using immobilized artificial membrane chromatography I: amended linear solvation energy relationships with the introduction of a molecular electronic factor.

PubMed

Li, Jie; Sun, Jin; Cui, Shengmiao; He, Zhonggui

2006-11-03

Linear solvation energy relationships (LSERs) amended by the introduction of a molecular electronic factor were employed to establish quantitative structure-retention relationships using immobilized artificial membrane (IAM) chromatography, in particular ionizable solutes. The chromatographic indices, log k(IAM), were determined by HPLC on an IAM.PC.DD2 column for 53 structurally diverse compounds, including neutral, acidic and basic compounds. Unlike neutral compounds, the IAM chromatographic retention of ionizable compounds was affected by their molecular charge state. When the mean net charge per molecule (delta) was introduced into the amended LSER as the sixth variable, the LSER regression coefficient was significantly improved for the test set including ionizable solutes. The delta coefficients of acidic and basic compounds were quite different indicating that the molecular electronic factor had a markedly different impact on the retention of acidic and basic compounds on IAM column. Ionization of acidic compounds containing a carboxylic group tended to impair their retention on IAM, while the ionization of basic compounds did not have such a marked effect. In addition, the extra-interaction with the polar head of phospholipids might cause a certain change in the retention of basic compounds. A comparison of calculated and experimental retention indices suggested that the semi-empirical LSER amended by the addition of a molecular electronic factor was able to reproduce adequately the experimental retention factors of the structurally diverse solutes investigated.

A resistive magnetohydrodynamics solver using modern C++ and the Boost library

NASA Astrophysics Data System (ADS)

Einkemmer, Lukas

2016-09-01

In this paper we describe the implementation of our C++ resistive magnetohydrodynamics solver. The framework developed facilitates the separation of the code implementing the specific numerical method and the physical model from the handling of boundary conditions and the management of the computational domain. In particular, this will allow us to use finite difference stencils which are only defined in the interior of the domain (the boundary conditions are handled automatically). We will discuss this and other design considerations and their impact on performance in some detail. In addition, we provide a documentation of the code developed and demonstrate that a performance comparable to Fortran can be achieved, while still maintaining a maximum of code readability and extensibility. Catalogue identifier: AFAH_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AFAH_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 592774 No. of bytes in distributed program, including test data, etc.: 43771395 Distribution format: tar.gz Programming language: C++03. Computer: PC, HPC systems. Operating system: POSIX compatible (extensively tested on various Linux systems). In fact only the timing class requires POSIX routines; all other parts of the program can be run on any system where a C++ compiler, Boost, CVODE, and an implementation of BLAS are available. RAM: Hundredths of Kilobytes to Gigabytes (depending on the problem size) Classification: 19.10, 4.3. External routines: Boost, CVODE, either a BLAS library or Intel MKL Nature of problem: An approximate solution to the equations of resistive magnetohydrodynamics for a given initial value and given boundary conditions is computed. Solution method: The discretization is performed using a finite difference approximation in space and the CVODE library in time (which employs a scheme based on the backward differentiation formulas). Restrictions: We consider the 2.5 dimensional case; that is, the magnetic field and the velocity field are three dimensional but all quantities depend only on x and y (but not z). Unusual features: We provide an implementation in C++ using the Boost library that combines high level techniques (which greatly increases code maintainability and extensibility) with performance that is comparable to Fortran implementations. Running time: From seconds to weeks (depending on the problem size).

Comparison of various error functions in predicting the optimum isotherm by linear and non-linear regression analysis for the sorption of basic red 9 by activated carbon.

PubMed

Kumar, K Vasanth; Porkodi, K; Rocha, F

2008-01-15

A comparison of linear and non-linear regression method in selecting the optimum isotherm was made to the experimental equilibrium data of basic red 9 sorption by activated carbon. The r(2) was used to select the best fit linear theoretical isotherm. In the case of non-linear regression method, six error functions namely coefficient of determination (r(2)), hybrid fractional error function (HYBRID), Marquardt's percent standard deviation (MPSD), the average relative error (ARE), sum of the errors squared (ERRSQ) and sum of the absolute errors (EABS) were used to predict the parameters involved in the two and three parameter isotherms and also to predict the optimum isotherm. Non-linear regression was found to be a better way to obtain the parameters involved in the isotherms and also the optimum isotherm. For two parameter isotherm, MPSD was found to be the best error function in minimizing the error distribution between the experimental equilibrium data and predicted isotherms. In the case of three parameter isotherm, r(2) was found to be the best error function to minimize the error distribution structure between experimental equilibrium data and theoretical isotherms. The present study showed that the size of the error function alone is not a deciding factor to choose the optimum isotherm. In addition to the size of error function, the theory behind the predicted isotherm should be verified with the help of experimental data while selecting the optimum isotherm. A coefficient of non-determination, K(2) was explained and was found to be very useful in identifying the best error function while selecting the optimum isotherm.

gpICA: A Novel Nonlinear ICA Algorithm Using Geometric Linearization

NASA Astrophysics Data System (ADS)

Nguyen, Thang Viet; Patra, Jagdish Chandra; Emmanuel, Sabu

2006-12-01

A new geometric approach for nonlinear independent component analysis (ICA) is presented in this paper. Nonlinear environment is modeled by the popular post nonlinear (PNL) scheme. To eliminate the nonlinearity in the observed signals, a novel linearizing method named as geometric post nonlinear ICA (gpICA) is introduced. Thereafter, a basic linear ICA is applied on these linearized signals to estimate the unknown sources. The proposed method is motivated by the fact that in a multidimensional space, a nonlinear mixture is represented by a nonlinear surface while a linear mixture is represented by a plane, a special form of the surface. Therefore, by geometrically transforming the surface representing a nonlinear mixture into a plane, the mixture can be linearized. Through simulations on different data sets, superior performance of gpICA algorithm has been shown with respect to other algorithms.

Military Curricula for Vocational & Technical Education. Basic Electricity and Electronics. CANTRAC A-100-0010. Module 32: Intermediate Oscillators; Module 33: Special Devices; Module 34: Linear Integrated Circuits. Students Guide.

ERIC Educational Resources Information Center

Chief of Naval Education and Training Support, Pensacola, FL.

This student guidebook is designed for use with the study booklets in modules 32 through 34 included in the military-developed course on basic electricity and electronics. The course is one of a number of military-developed curriculum packages selected for adaptation to vocational instructional and curriculum development in a civilian setting. An…

A study of two cases of comma-cloud cyclogenesis using a semigeostrophic model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Craig, G.C.; Cho, Hanru

1992-12-01

The linear stability of two atmospheric flows is studied, with basic-state data taken from environments where comma clouds are observed to flow. Each basic state features a baroclinic zone associated with an upper-level jet, with conditional instability on the north side. The semigeostrophic approximation is utilized, along with a simple parameterization for cumulus heating, and the eigenvalue problem is solved employing a Chebyshev spectral technique. 47 refs.

Analysis of Learning Curve Fitting Techniques.

DTIC Science & Technology

1987-09-01

1986. 15. Neter, John and others. Applied Linear Regression Models. Homewood IL: Irwin, 19-33. 16. SAS User’s Guide: Basics, Version 5 Edition. SAS... Linear Regression Techniques (15:23-52). Random errors are assumed to be normally distributed when using -# ordinary least-squares, according to Johnston...lot estimated by the improvement curve formula. For a more detailed explanation of the ordinary least-squares technique, see Neter, et. al., Applied

Research in Applied Mathematics Related to Mathematical System Theory.

DTIC Science & Technology

1977-06-01

This report deals with research results obtained in the field of mathematical system theory . Special emphasis was given to the following areas: (1...Linear system theory over a field: parametrization of multi-input, multi-output systems and the geometric structure of classes of systems of...constant dimension. (2) Linear systems over a ring: development of the theory for very general classes of rings. (3) Nonlinear system theory : basic

Computer-aided linear-circuit design.

NASA Technical Reports Server (NTRS)

Penfield, P.

1971-01-01

Usually computer-aided design (CAD) refers to programs that analyze circuits conceived by the circuit designer. Among the services such programs should perform are direct network synthesis, analysis, optimization of network parameters, formatting, storage of miscellaneous data, and related calculations. The program should be embedded in a general-purpose conversational language such as BASIC, JOSS, or APL. Such a program is MARTHA, a general-purpose linear-circuit analyzer embedded in APL.

Signal Prediction With Input Identification

NASA Technical Reports Server (NTRS)

Juang, Jer-Nan; Chen, Ya-Chin

1999-01-01

A novel coding technique is presented for signal prediction with applications including speech coding, system identification, and estimation of input excitation. The approach is based on the blind equalization method for speech signal processing in conjunction with the geometric subspace projection theory to formulate the basic prediction equation. The speech-coding problem is often divided into two parts, a linear prediction model and excitation input. The parameter coefficients of the linear predictor and the input excitation are solved simultaneously and recursively by a conventional recursive least-squares algorithm. The excitation input is computed by coding all possible outcomes into a binary codebook. The coefficients of the linear predictor and excitation, and the index of the codebook can then be used to represent the signal. In addition, a variable-frame concept is proposed to block the same excitation signal in sequence in order to reduce the storage size and increase the transmission rate. The results of this work can be easily extended to the problem of disturbance identification. The basic principles are outlined in this report and differences from other existing methods are discussed. Simulations are included to demonstrate the proposed method.

An Engineered Virus Library as a Resource for the Spectrum-wide Exploration of Virus and Vector Diversity.

PubMed

Zhang, Wenli; Fu, Jun; Liu, Jing; Wang, Hailong; Schiwon, Maren; Janz, Sebastian; Schaffarczyk, Lukas; von der Goltz, Lukas; Ehrke-Schulz, Eric; Dörner, Johannes; Solanki, Manish; Boehme, Philip; Bergmann, Thorsten; Lieber, Andre; Lauber, Chris; Dahl, Andreas; Petzold, Andreas; Zhang, Youming; Stewart, A Francis; Ehrhardt, Anja

2017-05-23

Adenoviruses (Ads) are large human-pathogenic double-stranded DNA (dsDNA) viruses presenting an enormous natural diversity associated with a broad variety of diseases. However, only a small fraction of adenoviruses has been explored in basic virology and biomedical research, highlighting the need to develop robust and adaptable methodologies and resources. We developed a method for high-throughput direct cloning and engineering of adenoviral genomes from different sources utilizing advanced linear-linear homologous recombination (LLHR) and linear-circular homologous recombination (LCHR). We describe 34 cloned adenoviral genomes originating from clinical samples, which were characterized by next-generation sequencing (NGS). We anticipate that this recombineering strategy and the engineered adenovirus library will provide an approach to study basic and clinical virology. High-throughput screening (HTS) of the reporter-tagged Ad library in a panel of cell lines including osteosarcoma disease-specific cell lines revealed alternative virus types with enhanced transduction and oncolysis efficiencies. This highlights the usefulness of this resource. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Linear Quadratic Gaussian Controller Design Using a Graphical User Interface: Application to the Beam-Waveguide Antennas

NASA Astrophysics Data System (ADS)

Maneri, E.; Gawronski, W.

1999-10-01

The linear quadratic Gaussian (LQG) design algorithms described in [2] and [5] have been used in the controller design of JPL's beam-waveguide [5] and 70-m [6] antennas. This algorithm significantly improves tracking precision in a windy environment. This article describes the graphical user interface (GUI) software for the design LQG controllers. It consists of two parts: the basic LQG design and the fine-tuning of the basic design using a constrained optimization algorithm. The presented GUI was developed to simplify the design process, to make the design process user-friendly, and to enable design of an LQG controller for one with a limited control engineering background. The user is asked to manipulate the GUI sliders and radio buttons to watch the antenna performance. Simple rules are given at the GUI display.

Physics of vascular brachytherapy.

PubMed

Jani, S K

1999-08-01

Basic physics plays an important role in understanding the clinical utility of radioisotopes in brachytherapy. Vascular brachytherapy is a very unique application of localized radiation in that dose levels very close to the source are employed to treat tissues within the arterial wall. This article covers basic physics of radioactivity and differentiates between beta and gamma radiations. Physical parameters such as activity, half-life, exposure and absorbed dose have been explained. Finally, the dose distribution around a point source and a linear source is described. The principles of basic physics are likely to play an important role in shaping the emerging technology and its application in vascular brachytherapy.

Noise characteristics of passive components for phased array applications

NASA Technical Reports Server (NTRS)

Sonmez, M. Kemal; Trew, Robert J.

1991-01-01

The results of a comparative study on noise characteristics of basic power combining/dividing and phase shifting schemes are presented. The theoretical basics of thermal noise in a passive linear multiport are discussed. A new formalism is presented to describe the noise behavior of the passive circuits, and it is shown that the fundamental results are conveniently achieved using this description. The results of analyses concerning the noise behavior of basic power combining/dividing structures (the Wilkinson combiner, 90 deg hybrid coupler, hybrid ring coupler, and the Lange coupler) are presented. Three types of PIN-diode switch phase shifters are analyzed in terms of noise performance.

Permanent-magnet linear alternators. I - Fundamental equations. II - Design guidelines

NASA Astrophysics Data System (ADS)

Boldea, I.; Nasar, S. A.

1987-01-01

The general equations of permanent-magnet heteropolar three-phase and single-phase linear alternators, powered by free-piston Stirling engines, are presented, with application to space power stations and domestic applications including solar power plants. The equations are applied to no-load and short-circuit conditions, illustrating the end-effect caused by the speed-reversal process. In the second part, basic design guidelines for a three-phase tubular linear alternator are given, and the procedure is demonstrated with the numerical example of the design of a 25-kVA, 14.4-m/s, 120/220-V, 60-Hz alternator.

A Method for Direct-Measurement of the Energy of Rupture of Impact Specimens

DTIC Science & Technology

1953-01-01

CONTENTS SECTION A - Poreword SFCTION B » ObjectiTes of the Current Investigation SECTION C - Basic Elements of an Impact Testing System ...SECTION D - Discussion lo Linear System 2 c Rotary System 3o Methods for Ifeasui ing the Energy of Rupture SECTION E « The Energy Measuring System ...has followed and to siironarize our techni<»l findings, Co BASIC ELEKEMTS OF AN IMPACT TESTING SYSTEM For the analytical purposes of this

RP-HPLC ANALYSIS OF ACIDIC AND BASIC DRUGS IN SYSTEMS WITH DIETHYLAMINE AS ELUENTS ADDITIVE.

PubMed

Petruczynik, Anna; Wroblewski, Karol; Strozek, Szymon; Waksmundzka-Hajnos, Monika

2016-11-01

The chromatographic behavior of some basic and acidic drugs was studied on Cl 8, Phenyl-Hexyl and Polar RP columns with methanol or acetonitrile as organic modifiers of aqueous mobile phases containing addition of diethylamine. Diethylamine plays a double function of silanol blocker reagent in analysis of basic drugs and ion-pair reagent in analysis of acidic drugs. Most symmetrical peaks and highest system efficiency were obtained on Phenyl-Hexyl and Polar RP columns in tested mobile phase systems compared to results obtained on C18 column. A new rapid, simple, specific and accurate reverse phase liquid chromatographic method was developed for the simultaneous determination of atorvastatin - antihyperlipidemic drug and amlodipine - calcium channel blocker in one pharmaceutical formulation. Atorvastatin is an acidic compounds while amlodipine is a basic substance. The chromatographic separation was carried out on Phenyl-Hexyl column by gradient elution mode with acetonitrile as organic modifier, acetate buffer at pH 3.5 and Q.025 M/L diethylamine. The proposed method was validated for specificity, precision, accuracy, linearity, and robustness. The linearity range of atorvastatin and amlodipine for 5 - 100 μg/mL was obtained with limits of-detection (LOD) 3.2750 gg/mL and 3.2102 μg/mL, respectively. The proposed method made use of DAD as a tool for peak identity and purity confirmation.

Solution of the Skyrme-Hartree-Fock-Bogolyubov equations in the Cartesian deformed harmonic-oscillator basis.. (VI) HFODD (v2.40h): A new version of the program

NASA Astrophysics Data System (ADS)

Dobaczewski, J.; Satuła, W.; Carlsson, B. G.; Engel, J.; Olbratowski, P.; Powałowski, P.; Sadziak, M.; Sarich, J.; Schunck, N.; Staszczak, A.; Stoitsov, M.; Zalewski, M.; Zduńczuk, H.

2009-11-01

We describe the new version (v2.40h) of the code HFODD which solves the nuclear Skyrme-Hartree-Fock or Skyrme-Hartree-Fock-Bogolyubov problem by using the Cartesian deformed harmonic-oscillator basis. In the new version, we have implemented: (i) projection on good angular momentum (for the Hartree-Fock states), (ii) calculation of the GCM kernels, (iii) calculation of matrix elements of the Yukawa interaction, (iv) the BCS solutions for state-dependent pairing gaps, (v) the HFB solutions for broken simplex symmetry, (vi) calculation of Bohr deformation parameters, (vii) constraints on the Schiff moments and scalar multipole moments, (viii) the DT2h transformations and rotations of wave functions, (ix) quasiparticle blocking for the HFB solutions in odd and odd-odd nuclei, (x) the Broyden method to accelerate the convergence, (xi) the Lipkin-Nogami method to treat pairing correlations, (xii) the exact Coulomb exchange term, (xiii) several utility options, and we have corrected three insignificant errors. New version program summaryProgram title: HFODD (v2.40h) Catalogue identifier: ADFL_v2_2 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADFL_v2_2.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 79 618 No. of bytes in distributed program, including test data, etc.: 372 548 Distribution format: tar.gz Programming language: FORTRAN-77 and Fortran-90 Computer: Pentium-III, AMD-Athlon, AMD-Opteron Operating system: UNIX, LINUX, Windows XP Has the code been vectorised or parallelized?: Yes, vectorised RAM: 10 Mwords Word size: The code is written in single-precision for use on a 64-bit processor. The compiler option -r8 or +autodblpad (or equivalent) has to be used to promote all real and complex single-precision floating-point items to double precision when the code is used on a 32-bit machine. Classification: 17.22 Catalogue identifier of previous version: ADFL_v2_1 Journal reference of previous version: Comput. Phys. Commun. 167 (2005) 214 External routines: Lapack (http://www.netlib.org/lapack/), Blas (http://www.netlib.org), linpack (http://www.netlib/linpack/) Does the new version supersede the previous version?: Yes Nature of problem: The nuclear mean-field and an analysis of its symmetries in realistic cases are the main ingredients of a description of nuclear states. Within the Local Density Approximation, or for a zero-range velocity-dependent Skyrme interaction, the nuclear mean-field is local and velocity dependent. The locality allows for an effective and fast solution of the self-consistent Hartree-Fock equations, even for heavy nuclei, and for various nucleonic (n-particle n-hole) configurations, deformations, excitation energies, or angular momenta. Similar Local Density Approximation in the particle-particle channel, which is equivalent to using a zero-range interaction, allows for a simple implementation of pairing effects within the Hartree-Fock-Bogolyubov method. Solution method: The program uses the Cartesian harmonic oscillator basis to expand single-particle or single-quasiparticle wave functions of neutrons and protons interacting by means of the Skyrme effective interaction and zero-range pairing interaction. The expansion coefficients are determined by the iterative diagonalization of the mean field Hamiltonians or Routhians which depend non-linearly on the local neutron and proton densities. Suitable constraints are used to obtain states corresponding to a given configuration, deformation or angular momentum. The method of solution has been presented in [1]. Summary of revisions: Projection on good angular momentum (for the Hartree-Fock states) has been implemented. Calculation of the GCM kernels has been implemented. Calculation of matrix elements of the Yukawa interaction has been implemented. The BCS solutions for state-dependent pairing gaps have been implemented. The HFB solutions for broken simplex symmetry have been implemented. Calculation of Bohr deformation parameters has been implemented. Constraints on the Schiff moments and scalar multipole moments have been implemented. The DT2h transformations and rotations of wave functions have been implemented. The quasiparticle blocking for the HFB solutions in odd and odd-odd nuclei has been implemented. The Broyden method to accelerate the convergence has been implemented. The Lipkin-Nogami method to treat pairing correlations has been implemented. The exact Coulomb exchange term has been implemented. Several utility options have been implemented. Three insignificant errors have been corrected. Restrictions: The main restriction is the CPU time required for calculations of heavy deformed nuclei and for a given precision required. Unusual features: The user must have access to an implementation of the BLAS (Basic Linear Algebra Subroutines), the NAGLIB subroutine F02AXE, or LAPACK subroutines ZHPEV, ZHPEVX, or ZHEEVR, which diagonalize complex Hermitian matrices, and the LINPACK subroutines ZGEDI and ZGECO, which invert arbitrary complex matrices and calculate determinants or provide another set of subroutines that can perform such a tasks. The LAPACK and LINPACK subroutines and an unoptimized version of the BLAS can be obtained from the Netlib Repository at the University of Tennessee, Knoxville: http://www.netlib.org/. Running time: One Hartree-Fock iteration for the superdeformed, rotating, parity conserving state of 15266Dy86 takes about six seconds on the AMD-Athlon 1600+ processor. Starting from the Woods-Saxon wave functions, about fifty iterations are required to obtain the energy converged within the precision of about 0.1 keV. In the case where every value of the angular velocity is converged separately, the complete superdeformed band with precisely determined dynamical moments J (2) can be obtained in forty minutes of CPU time on the AMD-Athlon 1600+ processor. This time can be often reduced by a factor of three when a self-consistent solution for a given rotational frequency is used as a starting point for a neighboring rotational frequency. References: J. Dobaczewski, J. Dudek, Comput. Phys. Commun. 102 (1997) 166.

Mathematics Conceptual Visualization with HyperCard.

ERIC Educational Resources Information Center

Haws, LaDawn

1992-01-01

Hypermedia provides an easy-to-use option for adding visualization, via the computer, to the classroom. Some examples of this medium are presented, including applications in basic linear algebra and calculus, and a tutorial in electromagnetism. (Author)

Feasibility study of basic characterization of MAGAT polymer gel using CBCT attached in linear accelerator: Preliminary study

NASA Astrophysics Data System (ADS)

Sathiyaraj, P.; Samuel, E. James jebaseelan

2018-01-01

The aim of this study is to evaluate the methacrylic acid, gelatin and tetrakis (hydroxymethyl) phosphonium chloride gel (MAGAT) by cone beam computed tomography (CBCT) attached with modern linear accelerator. To compare the results of standard diagnostic computed tomography (CT) with CBCT, different parameters such as linearity, sensitivity and temporal stability were checked. MAGAT gel showed good linearity for both diagnostic CT and CBCT measurements. Sensitivity and temporal stability were also comparable with diagnostic CT measurements. In both the modalities, the sensitivity of the MAGAT increased to 4 days and decreased till the 10th day of post irradiation. Since all measurements (linearity, sensitivity and temporal stability) from diagnostic CT and CBCT were comparable, CBCT could be a potential tool for dose analysis study for polymer gel dosimeter.

Applied Multiple Linear Regression: A General Research Strategy

ERIC Educational Resources Information Center

Smith, Brandon B.

1969-01-01

Illustrates some of the basic concepts and procedures for using regression analysis in experimental design, analysis of variance, analysis of covariance, and curvilinear regression. Applications to evaluation of instruction and vocational education programs are illustrated. (GR)

Composite-Material Point-Stress Analysis

NASA Technical Reports Server (NTRS)

Spears, F., S.

1982-01-01

PSANAL computes composite-laminate elastic and thermal properties and allowable load levels for any combination of applied membrane and bending loads occurring at a point. Basic linear orthotropic stress/ strain relationships and standard composite-laminate theory formulas are utilized.

Improving EMG based classification of basic hand movements using EMD.

PubMed

Sapsanis, Christos; Georgoulas, George; Tzes, Anthony; Lymberopoulos, Dimitrios

2013-01-01

This paper presents a pattern recognition approach for the identification of basic hand movements using surface electromyographic (EMG) data. The EMG signal is decomposed using Empirical Mode Decomposition (EMD) into Intrinsic Mode Functions (IMFs) and subsequently a feature extraction stage takes place. Various combinations of feature subsets are tested using a simple linear classifier for the detection task. Our results suggest that the use of EMD can increase the discrimination ability of the conventional feature sets extracted from the raw EMG signal.

Nonparallel stability of three-dimensional compressible boundary layers. Part 1: Stability analysis

NASA Technical Reports Server (NTRS)

El-Hady, N. M.

1980-01-01

A compressible linear stability theory is presented for nonparallel three-dimensional boundary-layer flows, taking into account the normal velocity component as well as the streamwise and spanwise variations of the basic flow. The method of multiple scales is used to account for the nonparallelism of the basic flow, and equations are derived for the spatial evolution of the disturbance amplitude and wavenumber. The numerical procedure for obtaining the solution of the nonparallel problem is outlined.

Direct perturbation theory for the dark soliton solution to the nonlinear Schroedinger equation with normal dispersion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yu Jialu; Yang Chunnuan; Cai Hao

2007-04-15

After finding the basic solutions of the linearized nonlinear Schroedinger equation by the method of separation of variables, the perturbation theory for the dark soliton solution is constructed by linear Green's function theory. In application to the self-induced Raman scattering, the adiabatic corrections to the soliton's parameters are obtained and the remaining correction term is given as a pure integral with respect to the continuous spectral parameter.

An efficient solver for large structured eigenvalue problems in relativistic quantum chemistry

NASA Astrophysics Data System (ADS)

Shiozaki, Toru

2017-01-01

We report an efficient program for computing the eigenvalues and symmetry-adapted eigenvectors of very large quaternionic (or Hermitian skew-Hamiltonian) matrices, using which structure-preserving diagonalisation of matrices of dimension N > 10, 000 is now routine on a single computer node. Such matrices appear frequently in relativistic quantum chemistry owing to the time-reversal symmetry. The implementation is based on a blocked version of the Paige-Van Loan algorithm, which allows us to use the Level 3 BLAS subroutines for most of the computations. Taking advantage of the symmetry, the program is faster by up to a factor of 2 than state-of-the-art implementations of complex Hermitian diagonalisation; diagonalising a 12, 800 × 12, 800 matrix took 42.8 (9.5) and 85.6 (12.6) minutes with 1 CPU core (16 CPU cores) using our symmetry-adapted solver and Intel Math Kernel Library's ZHEEV that is not structure-preserving, respectively. The source code is publicly available under the FreeBSD licence.

Taxonomic status of certain clapper rails of southwestern United States and northwestern Mexico

USGS Publications Warehouse

Banks, R.C.; Tomlinson, R.E.

1974-01-01

Examination of 58 Clapper Rail specimens taken in the breeding season from the Colorado Valley and the west coast of mainland Mexico verifies the distinctness of the races Rallus longirostris yomanensis, R. 1. rhizophorae, and R. 1. nayaritensis. Rallus 1. yumanensis is a relatively pale brown, pointed-winged, summer resident of freshwater marshes along the valley and delta of the Colorado River. Late winter specimens of yumanensis have been taken in freshwater and saltwater habitats in the Mexican states of Sinaloa and Puebla. Both R. 1. rhizophorae, a pale grayish bird, and R. 1. nayaritensis, a darker grayish form, are presumed year-round residents of the western Mexican mangrove swamps. Both have more rounded wings than yumanensis. The range of rhizophorae extends south along the coast from central Sonora to central Sinaloa, and that of nayaritensis from central Sinaloa to the vicinity of San Blas, Nayarit. Features of the range and characters of birds where the range of these two races approach each other are unclear.

Linear momentum, angular momentum and energy in the linear collision between two balls

NASA Astrophysics Data System (ADS)

Hanisch, C.; Hofmann, F.; Ziese, M.

2018-01-01

In an experiment of the basic physics laboratory, kinematical motion processes were analysed. The motion was recorded with a standard video camera having frame rates from 30 to 240 fps the videos were processed using video analysis software. Video detection was used to analyse the symmetric one-dimensional collision between two balls. Conservation of linear and angular momentum lead to a crossover from rolling to sliding directly after the collision. By variation of the rolling radius the system could be tuned from a regime in which the balls move away from each other after the collision to a situation in which they re-collide.

Using polyacrylate-coated SPME fibers to quantify sorption of polar and ionic organic contaminants to dissolved organic carbon.

PubMed

Haftka, Joris J-H; Scherpenisse, Peter; Jonker, Michiel T O; Hermens, Joop L M

2013-05-07

A passive sampling method using polyacrylate-coated solid-phase microextraction (SPME) fibers was applied to determine sorption of polar and ionic organic contaminants to dissolved organic carbon (DOC). The tested contaminants included pharmaceuticals, industrial chemicals, hormones, and pesticides and represented neutral, anionic, and cationic structures. Prior to the passive sampler application, sorption of the chemicals to the fibers was characterized. This was needed in order to accurately translate concentrations measured in fibers to freely dissolved aqueous concentrations during the sorption tests with DOC. Sorption isotherms of neutral compounds to the fiber were linear, whereas isotherms of basic chemicals covered a nonlinear and a linear range. Sorption of acidic and basic compounds to the fiber was pH-dependent and was dominated by sorption of the neutral sorbate species. Fiber- and DOC-water partition coefficients of neutral compounds were both linearly related to octanol-water partition coefficients (log Kow). The results of this study show that polyacrylate fibers can be used to quantify sorption to DOC of neutral and ionic contaminants, having multiple functional groups and spanning a wide hydrophobicity range (log Kow = 2.5-7.5).

Iterative algorithms for tridiagonal matrices on a WSI-multiprocessor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gajski, D.D.; Sameh, A.H.; Wisniewski, J.A.

1982-01-01

With the rapid advances in semiconductor technology, the construction of Wafer Scale Integration (WSI)-multiprocessors consisting of a large number of processors is now feasible. We illustrate the implementation of some basic linear algebra algorithms on such multiprocessors.

An Improved Search Approach for Solving Non-Convex Mixed-Integer Non Linear Programming Problems

NASA Astrophysics Data System (ADS)

Sitopu, Joni Wilson; Mawengkang, Herman; Syafitri Lubis, Riri

2018-01-01

The nonlinear mathematical programming problem addressed in this paper has a structure characterized by a subset of variables restricted to assume discrete values, which are linear and separable from the continuous variables. The strategy of releasing nonbasic variables from their bounds, combined with the “active constraint” method, has been developed. This strategy is used to force the appropriate non-integer basic variables to move to their neighbourhood integer points. Successful implementation of these algorithms was achieved on various test problems.

Tunable vertical-cavity surface-emitting laser with feedback to implement a pulsed neural model. 1. Principles and experimental demonstration.

PubMed

Romariz, Alexandre R S; Wagner, Kelvin H

2007-07-20

An optoelectronic implementation of a modified FitzHugh-Nagumo neuron model is proposed, analyzed, and experimentally demonstrated. The setup uses linear optics and linear electronics for implementing an optical wavelength-domain nonlinearity. The system attains instability through a bifurcation mechanism present in a class of neuron models, a fact that is shown analytically. The implementation exhibits basic features of neural dynamics including threshold, production of short pulses (or spikes), and refractoriness.

Direct perturbation theory for the dark soliton solution to the nonlinear Schrödinger equation with normal dispersion.

PubMed

Yu, Jia-Lu; Yang, Chun-Nuan; Cai, Hao; Huang, Nian-Ning

2007-04-01

After finding the basic solutions of the linearized nonlinear Schrödinger equation by the method of separation of variables, the perturbation theory for the dark soliton solution is constructed by linear Green's function theory. In application to the self-induced Raman scattering, the adiabatic corrections to the soliton's parameters are obtained and the remaining correction term is given as a pure integral with respect to the continuous spectral parameter.

Program Flow Analyzer. Volume 3

DTIC Science & Technology

1984-08-01

metrics are defined using these basic terms. Of interest is another measure for the size of the program, called the volume: V N x log 2 n. 5 The unit of...correlated to actual data and most useful for test. The formula des - cribing difficulty may be expressed as: nl X N2D - 2 -I/L *Difficulty then, is the...linearly independent program paths through any program graph. A maximal set of these linearly independent paths, called a "basis set," can always be found

Variational Theory of Motion of Curved, Twisted and Extensible Elastic Rods

DTIC Science & Technology

1993-01-18

nonlinear theory such as questions of existence of solutions and global behavior have been carried out by Antman (1976). His basic work entitled "The...Aerosp. Ens. Q017/018 16 REFERENCES Antman , S.S., "Ordinary Differential Equations of Non-Linear ElastIcity 1: Foundatious of the Theories of Non-Linearly...Elutic rods and Shells," A.R.M.A. 61 (1976), 307-351. Antman , S.S., "The Theory of Rods", Handbuch der Physik, Vol. Vla/2, Springer-Verlq, Berlin

Calculation of cogging force in a novel slotted linear tubular brushless permanent magnet motor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhu, Z.Q.; Hor, P.J.; Howe, D.

1997-09-01

There is an increasing requirement for controlled linear motion over short and long strokes, in the factory automation and packaging industries, for example. Linear brushless PM motors could offer significant advantages over conventional actuation technologies, such as motor driven cams and linkages and pneumatic rams--in terms of efficiency, operating bandwidth, speed and thrust control, stroke and positional accuracy, and indeed over other linear motor technologies, such as induction motors. Here, a finite element/analytical based technique for the prediction of cogging force in a novel topology of slotted linear brushless permanent magnet motor has been developed and validated. The various forcemore » components, which influence cogging are pre-calculated by the finite element analysis of some basic magnetic structures, facilitate the analytical synthesis of the resultant cogging force. The technique can be used to aid design for the minimization of cogging.« less

Axially deformed solution of the Skyrme-Hartree-Fock-Bogolyubov equations using the transformed harmonic oscillator basis (III) HFBTHO (v3.00): A new version of the program

NASA Astrophysics Data System (ADS)

Perez, R. Navarro; Schunck, N.; Lasseri, R.-D.; Zhang, C.; Sarich, J.

2017-11-01

We describe the new version 3.00 of the code HFBTHO that solves the nuclear Hartree-Fock (HF) or Hartree-Fock-Bogolyubov (HFB) problem by using the cylindrical transformed deformed harmonic oscillator basis. In the new version, we have implemented the following features: (i) the full Gogny force in both particle-hole and particle-particle channels, (ii) the calculation of the nuclear collective inertia at the perturbative cranking approximation, (iii) the calculation of fission fragment charge, mass and deformations based on the determination of the neck, (iv) the regularization of zero-range pairing forces, (v) the calculation of localization functions, (vi) a MPI interface for large-scale mass table calculations. Program Files doi:http://dx.doi.org/10.17632/c5g2f92by3.1 Licensing provisions: GPL v3 Programming language: FORTRAN-95 Journal reference of previous version: M.V. Stoitsov, N. Schunck, M. Kortelainen, N. Michel, H. Nam, E. Olsen, J. Sarich, and S. Wild, Comput. Phys. Commun. 184 (2013). Does the new version supersede the previous one: Yes Summary of revisions: 1. the Gogny force in both particle-hole and particle-particle channels was implemented; 2. the nuclear collective inertia at the perturbative cranking approximation was implemented; 3. fission fragment charge, mass and deformations were implemented based on the determination of the position of the neck between nascent fragments; 4. the regularization method of zero-range pairing forces was implemented; 5. the localization functions of the HFB solution were implemented; 6. a MPI interface for large-scale mass table calculations was implemented. Nature of problem:HFBTHO is a physics computer code that is used to model the structure of the nucleus. It is an implementation of the energy density functional (EDF) approach to atomic nuclei, where the energy of the nucleus is obtained by integration over space of some phenomenological energy density, which is itself a functional of the neutron and proton intrinsic densities. In the present version of HFBTHO, the energy density derives either from the zero-range Skyrme or the finite-range Gogny effective two-body interaction between nucleons. Nuclear super-fluidity is treated at the Hartree-Fock-Bogolyubov (HFB) approximation. Constraints on the nuclear shape allows probing the potential energy surface of the nucleus as needed e.g., for the description of shape isomers or fission. The implementation of a local scale transformation of the single-particle basis in which the HFB solutions are expanded provide a tool to properly compute the structure of weakly-bound nuclei. Solution method: The program uses the axial Transformed Harmonic Oscillator (THO) single-particle basis to expand quasiparticle wave functions. It iteratively diagonalizes the Hartree-Fock-Bogolyubov Hamiltonian based on generalized Skyrme-like energy densities and zero-range pairing interactions or the finite-range Gogny force until a self-consistent solution is found. A previous version of the program was presented in M.V. Stoitsov, N. Schunck, M. Kortelainen, N. Michel, H. Nam, E. Olsen, J. Sarich, and S. Wild, Comput. Phys. Commun. 184 (2013) 1592-1604 with much of the formalism presented in the original paper M.V. Stoitsov, J. Dobaczewski, W. Nazarewicz, P. Ring, Comput. Phys. Commun. 167 (2005) 43-63. Additional comments: The user must have access to (i) the LAPACK subroutines DSYEEVR, DSYEVD, DSYTRF and DSYTRI, and their dependencies, which compute eigenvalues and eigenfunctions of real symmetric matrices, (ii) the LAPACK subroutines DGETRI and DGETRF, which invert arbitrary real matrices, and (iii) the BLAS routines DCOPY, DSCAL, DGEMM and DGEMV for double-precision linear algebra (or provide another set of subroutines that can perform such tasks). The BLAS and LAPACK subroutines can be obtained from the Netlib Repository at the University of Tennessee, Knoxville: http://netlib2.cs.utk.edu/.

The Finite Lamplighter Groups: A Guided Tour

ERIC Educational Resources Information Center

Siehler, Jacob A.

2012-01-01

In this article, we present a family of finite groups, which provide excellent examples of the basic concepts of group theory. To work out the center, conjuagacy classes, and commutators of these groups, all that's required is a bit of linear algebra.

nu-TRLan User Guide Version 1.0: A High-Performance Software Package for Large-Scale Harmitian Eigenvalue Problems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yamazaki, Ichitaro; Wu, Kesheng; Simon, Horst

2008-10-27

The original software package TRLan, [TRLan User Guide], page 24, implements the thick restart Lanczos method, [Wu and Simon 2001], page 24, for computing eigenvalues {lambda} and their corresponding eigenvectors v of a symmetric matrix A: Av = {lambda}v. Its effectiveness in computing the exterior eigenvalues of a large matrix has been demonstrated, [LBNL-42982], page 24. However, its performance strongly depends on the user-specified dimension of a projection subspace. If the dimension is too small, TRLan suffers from slow convergence. If it is too large, the computational and memory costs become expensive. Therefore, to balance the solution convergence and costs,more » users must select an appropriate subspace dimension for each eigenvalue problem at hand. To free users from this difficult task, nu-TRLan, [LNBL-1059E], page 23, adjusts the subspace dimension at every restart such that optimal performance in solving the eigenvalue problem is automatically obtained. This document provides a user guide to the nu-TRLan software package. The original TRLan software package was implemented in Fortran 90 to solve symmetric eigenvalue problems using static projection subspace dimensions. nu-TRLan was developed in C and extended to solve Hermitian eigenvalue problems. It can be invoked using either a static or an adaptive subspace dimension. In order to simplify its use for TRLan users, nu-TRLan has interfaces and features similar to those of TRLan: (1) Solver parameters are stored in a single data structure called trl-info, Chapter 4 [trl-info structure], page 7. (2) Most of the numerical computations are performed by BLAS, [BLAS], page 23, and LAPACK, [LAPACK], page 23, subroutines, which allow nu-TRLan to achieve optimized performance across a wide range of platforms. (3) To solve eigenvalue problems on distributed memory systems, the message passing interface (MPI), [MPI forum], page 23, is used. The rest of this document is organized as follows. In Chapter 2 [Installation], page 2, we provide an installation guide of the nu-TRLan software package. In Chapter 3 [Example], page 3, we present a simple nu-TRLan example program. In Chapter 4 [trl-info structure], page 7, and Chapter 5 [trlan subroutine], page 14, we describe the solver parameters and interfaces in detail. In Chapter 6 [Solver parameters], page 21, we discuss the selection of the user-specified parameters. In Chapter 7 [Contact information], page 22, we give the acknowledgements and contact information of the authors. In Chapter 8 [References], page 23, we list reference to related works.« less

Accelerating scientific computations with mixed precision algorithms

NASA Astrophysics Data System (ADS)

Baboulin, Marc; Buttari, Alfredo; Dongarra, Jack; Kurzak, Jakub; Langou, Julie; Langou, Julien; Luszczek, Piotr; Tomov, Stanimire

2009-12-01

On modern architectures, the performance of 32-bit operations is often at least twice as fast as the performance of 64-bit operations. By using a combination of 32-bit and 64-bit floating point arithmetic, the performance of many dense and sparse linear algebra algorithms can be significantly enhanced while maintaining the 64-bit accuracy of the resulting solution. The approach presented here can apply not only to conventional processors but also to other technologies such as Field Programmable Gate Arrays (FPGA), Graphical Processing Units (GPU), and the STI Cell BE processor. Results on modern processor architectures and the STI Cell BE are presented. Program summaryProgram title: ITER-REF Catalogue identifier: AECO_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AECO_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 7211 No. of bytes in distributed program, including test data, etc.: 41 862 Distribution format: tar.gz Programming language: FORTRAN 77 Computer: desktop, server Operating system: Unix/Linux RAM: 512 Mbytes Classification: 4.8 External routines: BLAS (optional) Nature of problem: On modern architectures, the performance of 32-bit operations is often at least twice as fast as the performance of 64-bit operations. By using a combination of 32-bit and 64-bit floating point arithmetic, the performance of many dense and sparse linear algebra algorithms can be significantly enhanced while maintaining the 64-bit accuracy of the resulting solution. Solution method: Mixed precision algorithms stem from the observation that, in many cases, a single precision solution of a problem can be refined to the point where double precision accuracy is achieved. A common approach to the solution of linear systems, either dense or sparse, is to perform the LU factorization of the coefficient matrix using Gaussian elimination. First, the coefficient matrix A is factored into the product of a lower triangular matrix L and an upper triangular matrix U. Partial row pivoting is in general used to improve numerical stability resulting in a factorization PA=LU, where P is a permutation matrix. The solution for the system is achieved by first solving Ly=Pb (forward substitution) and then solving Ux=y (backward substitution). Due to round-off errors, the computed solution, x, carries a numerical error magnified by the condition number of the coefficient matrix A. In order to improve the computed solution, an iterative process can be applied, which produces a correction to the computed solution at each iteration, which then yields the method that is commonly known as the iterative refinement algorithm. Provided that the system is not too ill-conditioned, the algorithm produces a solution correct to the working precision. Running time: seconds/minutes

Statistics for nuclear engineers and scientists. Part 1. Basic statistical inference

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beggs, W.J.

1981-02-01

This report is intended for the use of engineers and scientists working in the nuclear industry, especially at the Bettis Atomic Power Laboratory. It serves as the basis for several Bettis in-house statistics courses. The objectives of the report are to introduce the reader to the language and concepts of statistics and to provide a basic set of techniques to apply to problems of the collection and analysis of data. Part 1 covers subjects of basic inference. The subjects include: descriptive statistics; probability; simple inference for normally distributed populations, and for non-normal populations as well; comparison of two populations; themore » analysis of variance; quality control procedures; and linear regression analysis.« less

Multilevel modelling: Beyond the basic applications.

PubMed

Wright, Daniel B; London, Kamala

2009-05-01

Over the last 30 years statistical algorithms have been developed to analyse datasets that have a hierarchical/multilevel structure. Particularly within developmental and educational psychology these techniques have become common where the sample has an obvious hierarchical structure, like pupils nested within a classroom. We describe two areas beyond the basic applications of multilevel modelling that are important to psychology: modelling the covariance structure in longitudinal designs and using generalized linear multilevel modelling as an alternative to methods from signal detection theory (SDT). Detailed code for all analyses is described using packages for the freeware R.

Methods for scalar-on-function regression.

PubMed

Reiss, Philip T; Goldsmith, Jeff; Shang, Han Lin; Ogden, R Todd

2017-08-01

Recent years have seen an explosion of activity in the field of functional data analysis (FDA), in which curves, spectra, images, etc. are considered as basic functional data units. A central problem in FDA is how to fit regression models with scalar responses and functional data points as predictors. We review some of the main approaches to this problem, categorizing the basic model types as linear, nonlinear and nonparametric. We discuss publicly available software packages, and illustrate some of the procedures by application to a functional magnetic resonance imaging dataset.

SPARSKIT: A basic tool kit for sparse matrix computations

NASA Technical Reports Server (NTRS)

Saad, Youcef

1990-01-01

Presented here are the main features of a tool package for manipulating and working with sparse matrices. One of the goals of the package is to provide basic tools to facilitate the exchange of software and data between researchers in sparse matrix computations. The starting point is the Harwell/Boeing collection of matrices for which the authors provide a number of tools. Among other things, the package provides programs for converting data structures, printing simple statistics on a matrix, plotting a matrix profile, and performing linear algebra operations with sparse matrices.

Extraction of basic roadway information for non-state roads in Florida.

DOT National Transportation Integrated Search

2015-06-01

The Florida Department of Transportation (FDOT) has continued to maintain a linear-referenced All-Roads map : that includes both state and non-state local roads. The state portion of the map could be populated with select data : from FDOTs R...

Whitham modulation theory for the Kadomtsev- Petviashvili equation.

PubMed

Ablowitz, Mark J; Biondini, Gino; Wang, Qiao

2017-08-01

The genus-1 Kadomtsev-Petviashvili (KP)-Whitham system is derived for both variants of the KP equation; namely the KPI and KPII equations. The basic properties of the KP-Whitham system, including symmetries, exact reductions and its possible complete integrability, together with the appropriate generalization of the one-dimensional Riemann problem for the Korteweg-de Vries equation are discussed. Finally, the KP-Whitham system is used to study the linear stability properties of the genus-1 solutions of the KPI and KPII equations; it is shown that all genus-1 solutions of KPI are linearly unstable, while all genus-1 solutions of KPII are linearly stable within the context of Whitham theory.

Whitham modulation theory for the Kadomtsev- Petviashvili equation

NASA Astrophysics Data System (ADS)

Ablowitz, Mark J.; Biondini, Gino; Wang, Qiao

2017-08-01

The genus-1 Kadomtsev-Petviashvili (KP)-Whitham system is derived for both variants of the KP equation; namely the KPI and KPII equations. The basic properties of the KP-Whitham system, including symmetries, exact reductions and its possible complete integrability, together with the appropriate generalization of the one-dimensional Riemann problem for the Korteweg-de Vries equation are discussed. Finally, the KP-Whitham system is used to study the linear stability properties of the genus-1 solutions of the KPI and KPII equations; it is shown that all genus-1 solutions of KPI are linearly unstable, while all genus-1 solutions of KPII are linearly stable within the context of Whitham theory.

Linear ordered collagen scaffolds loaded with collagen-binding basic fibroblast growth factor facilitate recovery of sciatic nerve injury in rats.

PubMed

Ma, Fukai; Xiao, Zhifeng; Chen, Bing; Hou, Xianglin; Dai, Jianwu; Xu, Ruxiang

2014-04-01

Natural biological functional scaffolds, consisting of biological materials filled with promoting elements, provide a promising strategy for the regeneration of peripheral nerve defects. Collagen conduits have been used widely due to their excellent biological properties. Linear ordered collagen scaffold (LOCS) fibers are good lumen fillers that can guide nerve regeneration in an ordered direction. In addition, basic fibroblast growth factor (bFGF) is important in the recovery of nerve injury. However, the traditional method for delivering bFGF to the lesion site has no long-term effect because of its short half-life and rapid diffusion. Therefore, we fused a specific collagen-binding domain (CBD) peptide to the N-terminal of native basic fibroblast growth factor (NAT-bFGF) to retain bFGF on the collagen scaffolds. In this study, a natural biological functional scaffold was constructed using collagen tubes filled with collagen-binding bFGF (CBD-bFGF)-loaded LOCS to promote regeneration in a 5-mm rat sciatic nerve transection model. Functional evaluation, histological investigation, and morphometric analysis indicated that the natural biological functional scaffold retained more bFGF at the injury site, guided axon growth, and promoted nerve regeneration as well as functional restoration.

Mixed convective/dynamic roll vortices and their effects on initial wind and temperature profiles

NASA Technical Reports Server (NTRS)

Haack, Tracy; Shirer, Hampton N.

1991-01-01

The onset and development of both dynamically and convectively forced boundary layer rolls are studied with linear and nonlinear analyses of a truncated spectral model of shallow Boussinesq flow. Emphasis is given here on the energetics of the dominant roll modes, on the magnitudes of the roll-induced modifications of the initial basic state wind and temperature profiles, and on the sensitivity of the linear stability results to the use of modified profiles as basic states. It is demonstrated that the roll circulations can produce substantial changes to the cross-roll component of the initial wind profile and that significant changes in orientation angle estimates can result from use of a roll-modified profile in the stability analysis. These results demonstrate that roll contributions must be removed from observed background wind profiles before using them to investigate the mechanisms underlying actual secondary flows in the boundary layer. The model is developed quite generally to accept arbitrary basic state wind profiles as dynamic forcing. An Ekman profile is chosen here merely to provide a means for easy comparison with other theoretical boundary layer studies; the ultimate application of the model is to study observed boundary layer profiles. Results of the analytic stability analysis are validated by comparing them with results from a larger linear model. For an appropriate Ekman depth, a complete set of transition curves is given in forcing parameter space for roll modes driven both thermally and dynamically. Preferred orientation angles, horizontal wavelengths and propagation frequencies, as well as energetics and wind profile modifications, are all shown to agree rather well with results from studies on Ekman layers as well as with studies on near-neutral and convective atmospheric boundary layers.

Longitudinal data analyses using linear mixed models in SPSS: concepts, procedures and illustrations.

PubMed

Shek, Daniel T L; Ma, Cecilia M S

2011-01-05

Although different methods are available for the analyses of longitudinal data, analyses based on generalized linear models (GLM) are criticized as violating the assumption of independence of observations. Alternatively, linear mixed models (LMM) are commonly used to understand changes in human behavior over time. In this paper, the basic concepts surrounding LMM (or hierarchical linear models) are outlined. Although SPSS is a statistical analyses package commonly used by researchers, documentation on LMM procedures in SPSS is not thorough or user friendly. With reference to this limitation, the related procedures for performing analyses based on LMM in SPSS are described. To demonstrate the application of LMM analyses in SPSS, findings based on six waves of data collected in the Project P.A.T.H.S. (Positive Adolescent Training through Holistic Social Programmes) in Hong Kong are presented.

Longitudinal Data Analyses Using Linear Mixed Models in SPSS: Concepts, Procedures and Illustrations

PubMed Central

Shek, Daniel T. L.; Ma, Cecilia M. S.

2011-01-01

Although different methods are available for the analyses of longitudinal data, analyses based on generalized linear models (GLM) are criticized as violating the assumption of independence of observations. Alternatively, linear mixed models (LMM) are commonly used to understand changes in human behavior over time. In this paper, the basic concepts surrounding LMM (or hierarchical linear models) are outlined. Although SPSS is a statistical analyses package commonly used by researchers, documentation on LMM procedures in SPSS is not thorough or user friendly. With reference to this limitation, the related procedures for performing analyses based on LMM in SPSS are described. To demonstrate the application of LMM analyses in SPSS, findings based on six waves of data collected in the Project P.A.T.H.S. (Positive Adolescent Training through Holistic Social Programmes) in Hong Kong are presented. PMID:21218263

Mathematical modelling in engineering: an alternative way to teach Linear Algebra

NASA Astrophysics Data System (ADS)

Domínguez-García, S.; García-Planas, M. I.; Taberna, J.

2016-10-01

Technological advances require that basic science courses for engineering, including Linear Algebra, emphasize the development of mathematical strengths associated with modelling and interpretation of results, which are not limited only to calculus abilities. Based on this consideration, we have proposed a project-based learning, giving a dynamic classroom approach in which students modelled real-world problems and turn gain a deeper knowledge of the Linear Algebra subject. Considering that most students are digital natives, we use the e-portfolio as a tool of communication between students and teachers, besides being a good place making the work visible. In this article, we present an overview of the design and implementation of a project-based learning for a Linear Algebra course taught during the 2014-2015 at the 'ETSEIB'of Universitat Politècnica de Catalunya (UPC).

Chiral resolution of spin angular momentum in linearly polarized and unpolarized light

PubMed Central

Hernández, R. J.; Mazzulla, A.; Provenzano, C.; Pagliusi, P.; Cipparrone, G.

2015-01-01

Linearly polarized (LP) and unpolarized (UP) light are racemic entities since they can be described as superposition of opposite circularly polarized (CP) components of equal amplitude. As a consequence they do not carry spin angular momentum. Chiral resolution of a racemate, i.e. separation of their chiral components, is usually performed via asymmetric interaction with a chiral entity. In this paper we provide an experimental evidence of the chiral resolution of linearly polarized and unpolarized Gaussian beams through the transfer of spin angular momentum to chiral microparticles. Due to the interplay between linear and angular momentum exchange, basic manipulation tasks, as trapping, spinning or orbiting of micro-objects, can be performed by light with zero helicity. The results might broaden the perspectives for development of miniaturized and cost-effective devices. PMID:26585284

Analysis of Cereal Starches by High Performance Size Exclusion Chromatography

USDA-ARS?s Scientific Manuscript database

Starch has unique physicochemical characteristics among carbohydrates. Most starch granules are a mixture of two sugar polymers: a highly branched polysaccharide named amylopectin, and a basically linear polysaccharide named amylose. The objective of this study was to develop a simple, one-step and ...

Laser SRS tracker for reverse prototyping tasks

NASA Astrophysics Data System (ADS)

Kolmakov, Egor; Redka, Dmitriy; Grishkanich, Aleksandr; Tsvetkov, Konstantin

2017-10-01

According to the current great interest concerning Large-Scale Metrology applications in many different fields of manufacturing industry, technologies and techniques for dimensional measurement have recently shown a substantial improvement. Ease-of-use, logistic and economic issues, as well as metrological performance, are assuming a more and more important role among system requirements. The project is planned to conduct experimental studies aimed at identifying the impact of the application of the basic laws of chip and microlasers as radiators on the linear-angular characteristics of existing measurement systems. The project is planned to conduct experimental studies aimed at identifying the impact of the application of the basic laws of microlasers as radiators on the linear-angular characteristics of existing measurement systems. The system consists of a distributed network-based layout, whose modularity allows to fit differently sized and shaped working volumes by adequately increasing the number of sensing units. Differently from existing spatially distributed metrological instruments, the remote sensor devices are intended to provide embedded data elaboration capabilities, in order to share the overall computational load.

Stationary waves on nonlinear quantum graphs. II. Application of canonical perturbation theory in basic graph structures.

PubMed

Gnutzmann, Sven; Waltner, Daniel

2016-12-01

We consider exact and asymptotic solutions of the stationary cubic nonlinear Schrödinger equation on metric graphs. We focus on some basic example graphs. The asymptotic solutions are obtained using the canonical perturbation formalism developed in our earlier paper [S. Gnutzmann and D. Waltner, Phys. Rev. E 93, 032204 (2016)2470-004510.1103/PhysRevE.93.032204]. For closed example graphs (interval, ring, star graph, tadpole graph), we calculate spectral curves and show how the description of spectra reduces to known characteristic functions of linear quantum graphs in the low-intensity limit. Analogously for open examples, we show how nonlinear scattering of stationary waves arises and how it reduces to known linear scattering amplitudes at low intensities. In the short-wavelength asymptotics we discuss how genuine nonlinear effects may be described using the leading order of canonical perturbation theory: bifurcation of spectral curves (and the corresponding solutions) in closed graphs and multistability in open graphs.

Equicontrollability and the model following problem

NASA Technical Reports Server (NTRS)

Curran, R. T.

1971-01-01

Equicontrollability and its application to the linear time-invariant model-following problem are discussed. The problem is presented in the form of two systems, the plant and the model. The requirement is to find a controller to apply to the plant so that the resultant compensated plant behaves, in an input-output sense, the same as the model. All systems are assumed to be linear and time-invariant. The basic approach is to find suitable equicontrollable realizations of the plant and model and to utilize feedback so as to produce a controller of minimal state dimension. The concept of equicontrollability is a generalization of control canonical (phase variable) form applied to multivariable systems. It allows one to visualize clearly the effects of feedback and to pinpoint the parameters of a multivariable system which are invariant under feedback. The basic contributions are the development of equicontrollable form; solution of the model-following problem in an entirely algorithmic way, suitable for computer programming; and resolution of questions on system decoupling.

Direct estimations of linear and nonlinear functionals of a quantum state.

PubMed

Ekert, Artur K; Alves, Carolina Moura; Oi, Daniel K L; Horodecki, Michał; Horodecki, Paweł; Kwek, L C

2002-05-27

We present a simple quantum network, based on the controlled-SWAP gate, that can extract certain properties of quantum states without recourse to quantum tomography. It can be used as a basic building block for direct quantum estimations of both linear and nonlinear functionals of any density operator. The network has many potential applications ranging from purity tests and eigenvalue estimations to direct characterization of some properties of quantum channels. Experimental realizations of the proposed network are within the reach of quantum technology that is currently being developed.

Perturbed effects at radiation physics

NASA Astrophysics Data System (ADS)

Külahcı, Fatih; Şen, Zekâi

2013-09-01

Perturbation methodology is applied in order to assess the linear attenuation coefficient, mass attenuation coefficient and cross-section behavior with random components in the basic variables such as the radiation amounts frequently used in the radiation physics and chemistry. Additionally, layer attenuation coefficient (LAC) and perturbed LAC (PLAC) are proposed for different contact materials. Perturbation methodology provides opportunity to obtain results with random deviations from the average behavior of each variable that enters the whole mathematical expression. The basic photon intensity variation expression as the inverse exponential power law (as Beer-Lambert's law) is adopted for perturbation method exposition. Perturbed results are presented not only in terms of the mean but additionally the standard deviation and the correlation coefficients. Such perturbation expressions provide one to assess small random variability in basic variables.

Basic nonlinear acoustics: an introduction for radiological physicists.

PubMed

Harpen, Michael D

2006-09-01

Presented is a brief introduction to nonlinear acoustics, a topic of increasing importance in modern diagnostic ultrasound. Specifically treated is shock wave and harmonic production in lossless media. We also present a description of linear attenuation mechanisms in soft tissue and finally nonlinear propagation in soft tissue.

SYSTEM THEORY: INTER-UNIVERSITY ELECTRONICS SERIES, VOLUME VIII,

DTIC Science & Technology

The book contains contributions in the area of general system theory , linear systems, nonlinear systems, stochastic and learning systems by...nationally and internationally known experts. It presents the most basic and important areas of system theory for the use and familiarization of mathematically-oriented nonspecialists. (Author)

The Launching Pad: Delivering Information Competence through the Web.

ERIC Educational Resources Information Center

Clay, Sariya Talip; Harlan, Sallie; Swanson, Judy

Traditionally, librarians have used printed workbooks to teach students basic information skills. With the emergence of the World Wide Web, opportunities are available to transform these static and linear tools into dynamic, interactive instructional resources. This paper describes the efforts of librarians at California Polytechnic State…

Short Range Planning for Educational Management.

ERIC Educational Resources Information Center

Turksen, I. B.; Holzman, A. G.

A planning cycle for any autonomous university entity contains five basic processes: information storage and retrieval forecasting, resource allocation, scheduling, and a term of study with a feedback loop. The resource allocation process is investigated for the development of shortrange planning models. Dynamic models wth linear and quadratic…

SIMD Optimization of Linear Expressions for Programmable Graphics Hardware

PubMed Central

Bajaj, Chandrajit; Ihm, Insung; Min, Jungki; Oh, Jinsang

2009-01-01

The increased programmability of graphics hardware allows efficient graphical processing unit (GPU) implementations of a wide range of general computations on commodity PCs. An important factor in such implementations is how to fully exploit the SIMD computing capacities offered by modern graphics processors. Linear expressions in the form of ȳ = Ax̄ + b̄, where A is a matrix, and x̄, ȳ and b̄ are vectors, constitute one of the most basic operations in many scientific computations. In this paper, we propose a SIMD code optimization technique that enables efficient shader codes to be generated for evaluating linear expressions. It is shown that performance can be improved considerably by efficiently packing arithmetic operations into four-wide SIMD instructions through reordering of the operations in linear expressions. We demonstrate that the presented technique can be used effectively for programming both vertex and pixel shaders for a variety of mathematical applications, including integrating differential equations and solving a sparse linear system of equations using iterative methods. PMID:19946569

Device with Functions of Linear Motor and Non-contact Power Collector for Wireless Drive

NASA Astrophysics Data System (ADS)

Fujii, Nobuo; Mizuma, Tsuyoshi

The authors propose a new apparatus with functions of propulsion and non-contact power collection for a future vehicle which can run like an electric vehicle supplied from the onboard battery source in most of the root except near stations. The batteries or power-capacitors are non-contact charged from the winding connected with commercial power on ground in the stations etc. The apparatus has both functions of linear motor and transformer, and the basic configuration is a wound-secondary type linear induction motor (LIM). In the paper, the wound type LIM with the concentrated single-phase winding for the primary member on the ground is dealt from the viewpoint of low cost arrangement. The secondary winding is changed to the single-phase connection for zero thrust in the transformer operation, and the two-phase connection for the linear motor respectively. The change of connection is done by the special converter for charge and linear drive on board. The characteristics are studied analytically.

Nonlinear (time domain) and linearized (time and frequency domain) solutions to the compressible Euler equations in conservation law form

NASA Technical Reports Server (NTRS)

Sreenivas, Kidambi; Whitfield, David L.

1995-01-01

Two linearized solvers (time and frequency domain) based on a high resolution numerical scheme are presented. The basic approach is to linearize the flux vector by expressing it as a sum of a mean and a perturbation. This allows the governing equations to be maintained in conservation law form. A key difference between the time and frequency domain computations is that the frequency domain computations require only one grid block irrespective of the interblade phase angle for which the flow is being computed. As a result of this and due to the fact that the governing equations for this case are steady, frequency domain computations are substantially faster than the corresponding time domain computations. The linearized equations are used to compute flows in turbomachinery blade rows (cascades) arising due to blade vibrations. Numerical solutions are compared to linear theory (where available) and to numerical solutions of the nonlinear Euler equations.

The relevance of basic sciences in undergraduate medical education.

PubMed

Lynch, C; Grant, T; McLoughlin, P; Last, J

2016-02-01

Evolving and changing undergraduate medical curricula raise concerns that there will no longer be a place for basic sciences. National and international trends show that 5-year programmes with a pre-requisite for school chemistry are growing more prevalent. National reports in Ireland show a decline in the availability of school chemistry and physics. This observational cohort study considers if the basic sciences of physics, chemistry and biology should be a prerequisite to entering medical school, be part of the core medical curriculum or if they have a place in the practice of medicine. Comparisons of means, correlation and linear regression analysis assessed the degree of association between predictors (school and university basic sciences) and outcomes (year and degree GPA) for entrants to a 6-year Irish medical programme between 2006 and 2009 (n = 352). We found no statistically significant difference in medical programme performance between students with/without prior basic science knowledge. The Irish school exit exam and its components were mainly weak predictors of performance (-0.043 ≥ r ≤ 0.396). Success in year one of medicine, which includes a basic science curriculum, was indicative of later success (0.194 ≥ r (2) ≤ 0.534). University basic sciences were found to be more predictive than school sciences in undergraduate medical performance in our institution. The increasing emphasis of basic sciences in medical practice and the declining availability of school sciences should mandate medical schools in Ireland to consider how removing basic sciences from the curriculum might impact on future applicants.

A Fortran 90 Hartree-Fock program for one-dimensional periodic π-conjugated systems using Pariser-Parr-Pople model

NASA Astrophysics Data System (ADS)

Kondayya, Gundra; Shukla, Alok

2012-03-01

Pariser-Parr-Pople (P-P-P) model Hamiltonian is employed frequently to study the electronic structure and optical properties of π-conjugated systems. In this paper we describe a Fortran 90 computer program which uses the P-P-P model Hamiltonian to solve the Hartree-Fock (HF) equation for infinitely long, one-dimensional, periodic, π-electron systems. The code is capable of computing the band structure, as also the linear optical absorption spectrum, by using the tight-binding and the HF methods. Furthermore, using our program the user can solve the HF equation in the presence of a finite external electric field, thereby, allowing the simulation of gated systems. We apply our code to compute various properties of polymers such as trans-polyacetylene, poly- para-phenylene, and armchair and zigzag graphene nanoribbons, in the infinite length limit. Program summaryProgram title: ppp_bulk.x Catalogue identifier: AEKW_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEKW_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 87 464 No. of bytes in distributed program, including test data, etc.: 2 046 933 Distribution format: tar.gz Programming language: Fortran 90 Computer: PCs and workstations Operating system: Linux, Code was developed and tested on various recent versions of 64-bit Fedora including Fedora 14 (kernel version 2.6.35.12-90). Classification: 7.3 External routines: This program needs to link with LAPACK/BLAS libraries compiled with the same compiler as the program. For the Intel Fortran Compiler we used the ACML library version 4.4.0, while for the gfortran compiler we used the libraries supplied with the Fedora distribution. Nature of problem: The electronic structure of one-dimensional periodic π-conjugated systems is an intense area of research at present because of the tremendous interest in the physics of conjugated polymers and graphene nanoribbons. The computer program described in this paper provides an efficient way of solving the Hartree-Fock equations for such systems within the P-P-P model. In addition to the Bloch orbitals, band structure, and the density of states, the program can also compute quantities such as the linear absorption spectrum, and the electro-absorption spectrum of these systems. Solution method: For a one-dimensional periodic π-conjugated system lying in the xy-plane, the single-particle Bloch orbitals are expressed as linear combinations of p-orbitals of individual atoms. Then using various parameters defining the P-P-P Hamiltonian, the Hartree-Fock equations are set up as a matrix eigenvalue problem in the k-space. Thereby, its solutions are obtained in a self-consistent manner, using the iterative diagonalizing technique at several k points. The band structure and the corresponding Bloch orbitals thus obtained are used to perform a variety of calculations such as the density of states, linear optical absorption spectrum, electro-absorption spectrum, etc. Running time: Most of the examples provided take only a few seconds to run. For a large system, however, depending on the system size, the run time may be a few minutes to a few hours.

Every Heavenly Body When Created Will Have No Motion, Linear, Rotational and/or Vibratory Motion, Singly or in Some Combination

NASA Astrophysics Data System (ADS)

Brekke, Stewart

2010-02-01

Each galaxy, star and planet is in a state of no motion, linear, rotational and/or vibratory motion. Orbital motion is linear motion in a force field such as gravity. These motions were created in the formation of the galaxy, star or planet unless modified by external events such as colliding galaxies or impacts such as meteors. Some motions, such as rotations and vibrations may be differential such as in the cases of our sun and the Milky Way galaxy. The basic equation for each heavenly body is as follows. E = mc^2 + 1/2mv^2 + 1/2I2̂+ 1/2Kx^2 + WG+ WE+ WM. )

Polarized electron sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Prepost, R.

1994-12-01

The fundamentals of polarized electron sources are described with particular application to the Stanford Linear Accelerator Center. The SLAC polarized electron source is based on the principle of polarized photoemission from Gallium Arsenide. Recent developments using epitaxially grown, strained Gallium Arsenide cathodes have made it possible to obtain electron polarization significantly in excess of the conventional 50% polarization limit. The basic principles for Gallium and Arsenide polarized photoemitters are reviewed, and the extension of the basic technique to strained cathode structures is described. Results from laboratory measurements of strained photocathodes as well as operational results from the SLAC polarized sourcemore » are presented.« less

An approximation theory for the identification of linear thermoelastic systems

NASA Technical Reports Server (NTRS)

Rosen, I. G.; Su, Chien-Hua Frank

1990-01-01

An abstract approximation framework and convergence theory for the identification of thermoelastic systems is developed. Starting from an abstract operator formulation consisting of a coupled second order hyperbolic equation of elasticity and first order parabolic equation for heat conduction, well-posedness is established using linear semigroup theory in Hilbert space, and a class of parameter estimation problems is then defined involving mild solutions. The approximation framework is based upon generic Galerkin approximation of the mild solutions, and convergence of solutions of the resulting sequence of approximating finite dimensional parameter identification problems to a solution of the original infinite dimensional inverse problem is established using approximation results for operator semigroups. An example involving the basic equations of one dimensional linear thermoelasticity and a linear spline based scheme are discussed. Numerical results indicate how the approach might be used in a study of damping mechanisms in flexible structures.

Global optimization algorithm for heat exchanger networks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Quesada, I.; Grossmann, I.E.

This paper deals with the global optimization of heat exchanger networks with fixed topology. It is shown that if linear area cost functions are assumed, as well as arithmetic mean driving force temperature differences in networks with isothermal mixing, the corresponding nonlinear programming (NLP) optimization problem involves linear constraints and a sum of linear fractional functions in the objective which are nonconvex. A rigorous algorithm is proposed that is based on a convex NLP underestimator that involves linear and nonlinear estimators for fractional and bilinear terms which provide a tight lower bound to the global optimum. This NLP problem ismore » used within a spatial branch and bound method for which branching rules are given. Basic properties of the proposed method are presented, and its application is illustrated with several example problems. The results show that the proposed method only requires few nodes in the branch and bound search.« less

An analysis of hypercritical states in elastic and inelastic systems

NASA Astrophysics Data System (ADS)

Kowalczk, Maciej

The author raises a wide range of problems whose common characteristic is an analysis of hypercritical states in elastic and inelastic systems. the article consists of two basic parts. The first part primarily discusses problems of modelling hypercritical states, while the second analyzes numerical methods (so-called continuation methods) used to solve non-linear problems. The original approaches for modelling hypercritical states found in this article include the combination of plasticity theory and an energy condition for cracking, accounting for the variability and cyclical nature of the forms of fracture of a brittle material under a die, and the combination of plasticity theory and a simplified description of the phenomenon of localization along a discontinuity line. The author presents analytical solutions of three non-linear problems for systems made of elastic/brittle/plastic and elastic/ideally plastic materials. The author proceeds to discuss the analytical basics of continuation methods and analyzes the significance of the parameterization of non-linear problems, provides a method for selecting control parameters based on an analysis of the rank of a rectangular matrix of a uniform system of increment equations, and also provides a new method for selecting an equilibrium path originating from a bifurcation point. The author provides a general outline of continuation methods based on an analysis of the rank of a matrix of a corrective system of equations. The author supplements his theoretical solutions with numerical solutions of non-linear problems for rod systems and problems of the plastic disintegration of a notched rectangular plastic plate.

Historical Surprises

ERIC Educational Resources Information Center

Stuewer, Roger H.

2006-01-01

The capsule histories of physics that students learn in their physics courses stem basically, I believe, from a linear view of history--that physicists in making fundamental discoveries follow a Royal Road to them, as Hermann von Helmholtz put it in 1892. The actual routes they follow, however, are generally nonlinear, and when historians display…

Demonstrating the Light-Emitting Diode.

ERIC Educational Resources Information Center

Johnson, David A.

1995-01-01

Describes a simple inexpensive circuit which can be used to quickly demonstrate the basic function and versatility of the solid state diode. Can be used to demonstrate the light-emitting diode (LED) as a light emitter, temperature sensor, light detector with both a linear and logarithmic response, and charge storage device. (JRH)

Discovering Authorities and Hubs in Different Topological Web Graph Structures.

ERIC Educational Resources Information Center

Meghabghab, George

2002-01-01

Discussion of citation analysis on the Web considers Web hyperlinks as a source to analyze citations. Topics include basic graph theory applied to Web pages, including matrices, linear algebra, and Web topology; and hubs and authorities, including a search technique called HITS (Hyperlink Induced Topic Search). (Author/LRW)

Determining Dissolved Oxygen Levels

ERIC Educational Resources Information Center

Boucher, Randy

2010-01-01

This project was used in a mathematical modeling and introduction to differential equations course for first-year college students. The students worked in two-person groups and were given three weeks to complete the project. Students were given this project three weeks into the course, after basic first order linear differential equation and…

Introductory Linear Regression Programs in Undergraduate Chemistry.

ERIC Educational Resources Information Center

Gale, Robert J.

1982-01-01

Presented are simple programs in BASIC and FORTRAN to apply the method of least squares. They calculate gradients and intercepts and express errors as standard deviations. An introduction of undergraduate students to such programs in a chemistry class is reviewed, and issues instructors should be aware of are noted. (MP)

Computer Service Technician "COMPS." Curriculum Grant 1985.

ERIC Educational Resources Information Center

Schoolcraft Coll., Livonia, MI.

This document is a curriculum guide for a program in computer service technology developed at Schoolcraft College, Livonia, Michigan. The program is designed to give students a strong background in the fundamentals of electricity, electronic devices, and basic circuits (digital and linear). The curriculum includes laboratory demonstrations of the…

A Graphical Approach to the Standard Principal-Agent Model.

ERIC Educational Resources Information Center

Zhou, Xianming

2002-01-01

States the principal-agent theory is difficult to teach because of its technical complexity and intractability. Indicates the equilibrium in the contract space is defined by the incentive parameter and insurance component of pay under a linear contract. Describes a graphical approach that students with basic knowledge of algebra and…

A class of stochastic optimization problems with one quadratic & several linear objective functions and extended portfolio selection model

NASA Astrophysics Data System (ADS)

Xu, Jiuping; Li, Jun

2002-09-01

In this paper a class of stochastic multiple-objective programming problems with one quadratic, several linear objective functions and linear constraints has been introduced. The former model is transformed into a deterministic multiple-objective nonlinear programming model by means of the introduction of random variables' expectation. The reference direction approach is used to deal with linear objectives and results in a linear parametric optimization formula with a single linear objective function. This objective function is combined with the quadratic function using the weighted sums. The quadratic problem is transformed into a linear (parametric) complementary problem, the basic formula for the proposed approach. The sufficient and necessary conditions for (properly, weakly) efficient solutions and some construction characteristics of (weakly) efficient solution sets are obtained. An interactive algorithm is proposed based on reference direction and weighted sums. Varying the parameter vector on the right-hand side of the model, the DM can freely search the efficient frontier with the model. An extended portfolio selection model is formed when liquidity is considered as another objective to be optimized besides expectation and risk. The interactive approach is illustrated with a practical example.

Application of Higuchi's fractal dimension from basic to clinical neurophysiology: A review.

PubMed

Kesić, Srdjan; Spasić, Sladjana Z

2016-09-01

For more than 20 years, Higuchi's fractal dimension (HFD), as a nonlinear method, has occupied an important place in the analysis of biological signals. The use of HFD has evolved from EEG and single neuron activity analysis to the most recent application in automated assessments of different clinical conditions. Our objective is to provide an updated review of the HFD method applied in basic and clinical neurophysiological research. This article summarizes and critically reviews a broad literature and major findings concerning the applications of HFD for measuring the complexity of neuronal activity during different neurophysiological conditions. The source of information used in this review comes from the PubMed, Scopus, Google Scholar and IEEE Xplore Digital Library databases. The review process substantiated the significance, advantages and shortcomings of HFD application within all key areas of basic and clinical neurophysiology. Therefore, the paper discusses HFD application alone, combined with other linear or nonlinear measures, or as a part of automated methods for analyzing neurophysiological signals. The speed, accuracy and cost of applying the HFD method for research and medical diagnosis make it stand out from the widely used linear methods. However, only a combination of HFD with other nonlinear methods ensures reliable and accurate analysis of a wide range of neurophysiological signals. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Effect of n-octanol in the mobile phase on lipophilicity determination by reversed-phase high-performance liquid chromatography on a modified silica column.

PubMed

Benhaim, Deborah; Grushka, Eli

2008-10-31

In this study, we show that the addition of n-octanol to the mobile phase improves the chromatographic determination of lipophilicity parameters of xenobiotics (neutral solutes, acidic, neutral and basic drugs) on a Phenomenex Gemini C18 column. The Gemini C18 column is a new generation hybrid silica-based column with an extended pH range capability. The wide pH range (2-12) afforded the examination of basic drugs and acidic drugs in their neutral form. Extrapolated retention factor values, [Formula: see text] , obtained on the above column with the n-octanol-modified mobile phase were very well correlated (1:1 correlation) with literature values of logP (logarithm of the partition coefficient in n-octanol/water) of neutral compounds and neutral drugs (69). In addition, we found good linear correlations between measured [Formula: see text] values and calculated values of the logarithm of the distribution coefficient at pH 7.0 (logD(7.0)) for ionized acidic and basic drugs (r(2)=0.95). The Gemini C18 phase was characterized using the linear solvation energy relationship (LSER) model of Abraham. The LSER system constants for the column were compared to the LSER constants of n-octanol/water extraction system using the Tanaka radar plots. The comparison shows that the two methods are nearly equivalent.

The performance of low-cost commercial cloud computing as an alternative in computational chemistry.

PubMed

Thackston, Russell; Fortenberry, Ryan C

2015-05-05

The growth of commercial cloud computing (CCC) as a viable means of computational infrastructure is largely unexplored for the purposes of quantum chemistry. In this work, the PSI4 suite of computational chemistry programs is installed on five different types of Amazon World Services CCC platforms. The performance for a set of electronically excited state single-point energies is compared between these CCC platforms and typical, "in-house" physical machines. Further considerations are made for the number of cores or virtual CPUs (vCPUs, for the CCC platforms), but no considerations are made for full parallelization of the program (even though parallelization of the BLAS library is implemented), complete high-performance computing cluster utilization, or steal time. Even with this most pessimistic view of the computations, CCC resources are shown to be more cost effective for significant numbers of typical quantum chemistry computations. Large numbers of large computations are still best utilized by more traditional means, but smaller-scale research may be more effectively undertaken through CCC services. © 2015 Wiley Periodicals, Inc.

A projected preconditioned conjugate gradient algorithm for computing many extreme eigenpairs of a Hermitian matrix [A projected preconditioned conjugate gradient algorithm for computing a large eigenspace of a Hermitian matrix

DOE PAGES

Vecharynski, Eugene; Yang, Chao; Pask, John E.

2015-02-25

Here, we present an iterative algorithm for computing an invariant subspace associated with the algebraically smallest eigenvalues of a large sparse or structured Hermitian matrix A. We are interested in the case in which the dimension of the invariant subspace is large (e.g., over several hundreds or thousands) even though it may still be small relative to the dimension of A. These problems arise from, for example, density functional theory (DFT) based electronic structure calculations for complex materials. The key feature of our algorithm is that it performs fewer Rayleigh–Ritz calculations compared to existing algorithms such as the locally optimalmore » block preconditioned conjugate gradient or the Davidson algorithm. It is a block algorithm, and hence can take advantage of efficient BLAS3 operations and be implemented with multiple levels of concurrency. We discuss a number of practical issues that must be addressed in order to implement the algorithm efficiently on a high performance computer.« less

Price analysis of multiple sclerosis disease-modifying therapies marketed in the United States.

PubMed

Bin Sawad, Aseel; Seoane-Vazquez, Enrique; Rodriguez-Monguio, Rosa; Turkistani, Fatema

2016-11-01

This study assessed trends in the average wholesale price (AWP) at the market entry of disease-modifying therapies (DMTs) approved by Food and Drug Administration (FDA) in the period 1987-2014. DMT regulatory information was derived from the FDA website. The AWPs per unit at market entry data were derived from the Red Book (Truven Health Analytics Inc.). The AWP history for each DMT was collected from its date of approval to 31 December 2014. The FDA approved label defined daily dose (DDD) for adult patients was obtained from FDA approved labels. The AWP per DDD and the AWP/DDD per year of therapy were computed. Descriptive statistics, Wilcoxon tests, t-test, and multiple linear regression were performed. The statistical significance level was set at 0.05. The FDA approved 12 multiple sclerosis (MS) DMTs, including five new drug applications (NDAs) and seven biologic license applications (BLAs) as of 31 December 2014. The FDA granted orphan designation to five DMTs. There was one DMT approved by the FDA in the 1980s, three in the 1990s, three in 2000s, and five in the period 2010-2014. The market entry inflation-adjusted AWP per DDD was $10.23 for the first DMT (mitoxantrone hydrochloride) that was approved in the 1980s. The median market entry inflation-adjusted AWP per DDD was $12.41 (interquartile range [IQR] = 4.51) for DMTs approved in the 1990s, $71.26 (IQR = 58.35) in the 2000s, and $172.56 (IQR = 84.97) in the period 2010-2014. The median AWP per DDD was statistically significantly different (p = 0.011) for orphan (median = $41.82, IQR = 56.077) compared to non-orphan drugs (median = $171.32, IQR = 199.29). Year of market entry was positively associated with DMT prices at US market entry (p = 0.01). The AWP per DDD for DMTs at market entry increased substantially over time. The increase in DMTs prices exceeded the general consumer price index.

A four-component model of the action potential in mouse detrusor smooth muscle cell

PubMed Central

Brain, Keith L.; Young, John S.; Manchanda, Rohit

2018-01-01

Background and hypothesis Detrusor smooth muscle cells (DSMCs) of the urinary bladder are electrically connected to one another via gap junctions and form a three dimensional syncytium. DSMCs exhibit spontaneous electrical activity, including passive depolarizations and action potentials. The shapes of spontaneous action potentials (sAPs) observed from a single DSM cell can vary widely. The biophysical origins of this variability, and the precise components which contribute to the complex shapes observed are not known. To address these questions, the basic components which constitute the sAPs were investigated. We hypothesized that linear combinations of scaled versions of these basic components can produce sAP shapes observed in the syncytium. Methods and results The basic components were identified as spontaneous evoked junction potentials (sEJP), native AP (nAP), slow after hyperpolarization (sAHP) and very slow after hyperpolarization (vsAHP). The experimental recordings were grouped into two sets: a training data set and a testing data set. A training set was used to estimate the components, and a test set to evaluate the efficiency of the estimated components. We found that a linear combination of the identified components when appropriately amplified and time shifted replicated various AP shapes to a high degree of similarity, as quantified by the root mean square error (RMSE) measure. Conclusions We conclude that the four basic components—sEJP, nAP, sAHP, and vsAHP—identified and isolated in this work are necessary and sufficient to replicate all varieties of the sAPs recorded experimentally in DSMCs. This model has the potential to generate testable hypotheses that can help identify the physiological processes underlying various features of the sAPs. Further, this model also provides a means to classify the sAPs into various shape classes. PMID:29351282

A four-component model of the action potential in mouse detrusor smooth muscle cell.

PubMed

Padmakumar, Mithun; Brain, Keith L; Young, John S; Manchanda, Rohit

2018-01-01

Detrusor smooth muscle cells (DSMCs) of the urinary bladder are electrically connected to one another via gap junctions and form a three dimensional syncytium. DSMCs exhibit spontaneous electrical activity, including passive depolarizations and action potentials. The shapes of spontaneous action potentials (sAPs) observed from a single DSM cell can vary widely. The biophysical origins of this variability, and the precise components which contribute to the complex shapes observed are not known. To address these questions, the basic components which constitute the sAPs were investigated. We hypothesized that linear combinations of scaled versions of these basic components can produce sAP shapes observed in the syncytium. The basic components were identified as spontaneous evoked junction potentials (sEJP), native AP (nAP), slow after hyperpolarization (sAHP) and very slow after hyperpolarization (vsAHP). The experimental recordings were grouped into two sets: a training data set and a testing data set. A training set was used to estimate the components, and a test set to evaluate the efficiency of the estimated components. We found that a linear combination of the identified components when appropriately amplified and time shifted replicated various AP shapes to a high degree of similarity, as quantified by the root mean square error (RMSE) measure. We conclude that the four basic components-sEJP, nAP, sAHP, and vsAHP-identified and isolated in this work are necessary and sufficient to replicate all varieties of the sAPs recorded experimentally in DSMCs. This model has the potential to generate testable hypotheses that can help identify the physiological processes underlying various features of the sAPs. Further, this model also provides a means to classify the sAPs into various shape classes.

Optically stimulated luminescence (OSL) dosimetry in medicine.

PubMed

Yukihara, E G; McKeever, S W S

2008-10-21

This paper reviews fundamental and practical aspects of optically stimulated luminescence (OSL) dosimetry pertaining to applications in medicine, having particularly in mind new researchers and medical physicists interested in gaining familiarity with the field. A basic phenomenological model for OSL is presented and the key processes affecting the outcome of an OSL measurement are discussed. Practical aspects discussed include stimulation modalities (continuous-wave OSL, pulsed OSL and linear modulation OSL), basic experimental setup, available OSL readers, optical fiber systems and basic properties of available OSL dosimeters. Finally, results from the recent literature on applications of OSL in radiotherapy, radiodiagnostics and heavy charged particle dosimetry are discussed in light of the theoretical and practical framework presented in this review. Open questions and future challenges in OSL dosimetry are highlighted as a guide to the research needed to further advance the field.

Complexity and health professions education: a basic glossary.

PubMed

Mennin, Stewart

2010-08-01

The study of health professions education in the context of complexity science and complex adaptive systems involves different concepts and terminology that are likely to be unfamiliar to many health professions educators. A list of selected key terms and definitions from the literature of complexity science is provided to assist readers to navigate familiar territory from a different perspective. include agent, attractor, bifurcation, chaos, co-evolution, collective variable, complex adaptive systems, complexity science, deterministic systems, dynamical system, edge of chaos, emergence, equilibrium, far from equilibrium, fuzzy boundaries, linear system, non-linear system, random, self-organization and self-similarity.

Exact solution of some linear matrix equations using algebraic methods

NASA Technical Reports Server (NTRS)

Djaferis, T. E.; Mitter, S. K.

1979-01-01

Algebraic methods are used to construct the exact solution P of the linear matrix equation PA + BP = - C, where A, B, and C are matrices with real entries. The emphasis of this equation is on the use of finite algebraic procedures which are easily implemented on a digital computer and which lead to an explicit solution to the problem. The paper is divided into six sections which include the proof of the basic lemma, the Liapunov equation, and the computer implementation for the rational, integer and modular algorithms. Two numerical examples are given and the entire calculation process is depicted.

Computer simulation results of attitude estimation of earth orbiting satellites

NASA Technical Reports Server (NTRS)

Kou, S. R.

1976-01-01

Computer simulation results of attitude estimation of Earth-orbiting satellites (including Space Telescope) subjected to environmental disturbances and noises are presented. Decomposed linear recursive filter and Kalman filter were used as estimation tools. Six programs were developed for this simulation, and all were written in the basic language and were run on HP 9830A and HP 9866A computers. Simulation results show that a decomposed linear recursive filter is accurate in estimation and fast in response time. Furthermore, for higher order systems, this filter has computational advantages (i.e., less integration errors and roundoff errors) over a Kalman filter.

Experimental Investigation on the Basic Law of Directional Hydraulic Fracturing Controlled by Dense Linear Multi-Hole Drilling

NASA Astrophysics Data System (ADS)

Zhao, Xinglong; Huang, Bingxiang; Wang, Zhen

2018-06-01

Directional rupture is a significant and routine problem for ground control in mines. Directional hydraulic fracturing controlled by dense linear multi-hole drilling was proposed. The physical model experiment, performed by the large-scale true triaxial hydraulic fracturing experimental system, aims to investigate the basic law of directional hydraulic fracturing controlled by dense linear multi-hole drilling, the impact of three different pumping modes on the initiation and propagation of hydraulic fractures among boreholes are particular investigated. The experimental results indicated that there are mutual impacts among different boreholes during crack propagation, which leads to a trend of fracture connection. Furthermore, during propagation, the fractures not only exhibit an overall bias toward the direction in which the boreholes are scattered but also partially offset against the borehole axes and intersect. The directional fracturing effect of equivalent pumping rate in each borehole is better than the other two pumping modes. In practical applications, because of rock mass heterogeneity, there may be differences in terms of filtration rate and effective input volume in different boreholes; thus, water pressure increase and rupture are not simultaneous in different boreholes. Additionally, if the crack initiation directions of different boreholes at different times are not consistent with each other, more lamellar failure planes will occur, and the mutual influences of these lamellar failure planes cause fractures to extend and intersect.

Body Composition of Bangladeshi Children: Comparison and Development of Leg-to-Leg Bioelectrical Impedance Equation

PubMed Central

Khan, I.; Hawlader, Sophie Mohammad Delwer Hossain; Arifeen, Shams El; Moore, Sophie; Hills, Andrew P.; Wells, Jonathan C.; Persson, Lars-Åke; Kabir, Iqbal

2012-01-01

The aim of this study was to investigate the validity of the Tanita TBF 300A leg-to-leg bioimpedance analyzer for estimating fat-free mass (FFM) in Bangladeshi children aged 4-10 years and to develop novel prediction equations for use in this population, using deuterium dilution as the reference method. Two hundred Bangladeshi children were enrolled. The isotope dilution technique with deuterium oxide was used for estimation of total body water (TBW). FFM estimated by Tanita was compared with results of deuterium oxide dilution technique. Novel prediction equations were created for estimating FFM, using linear regression models, fitting child's height and impedance as predictors. There was a significant difference in FFM and percentage of body fat (BF%) between methods (p<0.01), Tanita underestimating TBW in boys (p=0.001) and underestimating BF% in girls (p<0.001). A basic linear regression model with height and impedance explained 83% of the variance in FFM estimated by deuterium oxide dilution technique. The best-fit equation to predict FFM from linear regression modelling was achieved by adding weight, sex, and age to the basic model, bringing the adjusted R2 to 89% (standard error=0.90, p<0.001). These data suggest Tanita analyzer may be a valid field-assessment technique in Bangladeshi children when using population-specific prediction equations, such as the ones developed here. PMID:23082630

Chaos in World Politics: A Reflection

NASA Astrophysics Data System (ADS)

Ferreira, Manuel Alberto Martins; Filipe, José António Candeias Bonito; Coelho, Manuel F. P.; Pedro, Isabel C.

Chaos theory results from natural scientists' findings in the area of non-linear dynamics. The importance of related models has increased in the last decades, by studying the temporal evolution of non-linear systems. In consequence, chaos is one of the concepts that most rapidly have been expanded in what research topics respects. Considering that relationships in non-linear systems are unstable, chaos theory aims to understand and to explain this kind of unpredictable aspects of nature, social life, the uncertainties, the nonlinearities, the disorders and confusion, scientifically it represents a disarray connection, but basically it involves much more than that. The existing close relationship between change and time seems essential to understand what happens in the basics of chaos theory. In fact, this theory got a crucial role in the explanation of many phenomena. The relevance of this kind of theories has been well recognized to explain social phenomena and has permitted new advances in the study of social systems. Chaos theory has also been applied, particularly in the context of politics, in this area. The goal of this chapter is to make a reflection on chaos theory - and dynamical systems such as the theories of complexity - in terms of the interpretation of political issues, considering some kind of events in the political context and also considering the macro-strategic ideas of states positioning in the international stage.

Linear combination reading program for capture gamma rays

USGS Publications Warehouse

Tanner, Allan B.

1971-01-01

This program computes a weighting function, Qj, which gives a scalar output value of unity when applied to the spectrum of a desired element and a minimum value (considering statistics) when applied to spectra of materials not containing the desired element. Intermediate values are obtained for materials containing the desired element, in proportion to the amount of the element they contain. The program is written in the BASIC language in a format specific to the Hewlett-Packard 2000A Time-Sharing System, and is an adaptation of an earlier program for linear combination reading for X-ray fluorescence analysis (Tanner and Brinkerhoff, 1971). Following the program is a sample run from a study of the application of the linear combination technique to capture-gamma-ray analysis for calcium (report in preparation).

Comparing barrier algorithms

NASA Technical Reports Server (NTRS)

Arenstorf, Norbert S.; Jordan, Harry F.

1987-01-01

A barrier is a method for synchronizing a large number of concurrent computer processes. After considering some basic synchronization mechanisms, a collection of barrier algorithms with either linear or logarithmic depth are presented. A graphical model is described that profiles the execution of the barriers and other parallel programming constructs. This model shows how the interaction between the barrier algorithms and the work that they synchronize can impact their performance. One result is that logarithmic tree structured barriers show good performance when synchronizing fixed length work, while linear self-scheduled barriers show better performance when synchronizing fixed length work with an imbedded critical section. The linear barriers are better able to exploit the process skew associated with critical sections. Timing experiments, performed on an eighteen processor Flex/32 shared memory multiprocessor, that support these conclusions are detailed.

LPmerge: an R package for merging genetic maps by linear programming.

PubMed

Endelman, Jeffrey B; Plomion, Christophe

2014-06-01

Consensus genetic maps constructed from multiple populations are an important resource for both basic and applied research, including genome-wide association analysis, genome sequence assembly and studies of evolution. The LPmerge software uses linear programming to efficiently minimize the mean absolute error between the consensus map and the linkage maps from each population. This minimization is performed subject to linear inequality constraints that ensure the ordering of the markers in the linkage maps is preserved. When marker order is inconsistent between linkage maps, a minimum set of ordinal constraints is deleted to resolve the conflicts. LPmerge is on CRAN at http://cran.r-project.org/web/packages/LPmerge. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Adaptive finite element methods for two-dimensional problems in computational fracture mechanics

NASA Technical Reports Server (NTRS)

Min, J. B.; Bass, J. M.; Spradley, L. W.

1994-01-01

Some recent results obtained using solution-adaptive finite element methods in two-dimensional problems in linear elastic fracture mechanics are presented. The focus is on the basic issue of adaptive finite element methods for validating the new methodology by computing demonstration problems and comparing the stress intensity factors to analytical results.

Basic Research Plan.

DTIC Science & Technology

1996-05-01

detection, catalysts for enhancing and controlling energetic reactions, synthesis of new compounds (e.g., narrow band-gap materials and non-linear...design for synthesis of advanced materials Fabricate porous lightweight and resilient structural materials with novel properties and uses Demonstrate...elements for 10 nm computer memory elements Demonstrate enhanced propellants and explosives with nanoparticle surface chemistry Demonstrate sensing of

Differential geometric methods in system theory.

NASA Technical Reports Server (NTRS)

Brockett, R. W.

1971-01-01

Discussion of certain problems in system theory which have been or might be solved using some basic concepts from differential geometry. The problems considered involve differential equations, controllability, optimal control, qualitative behavior, stochastic processes, and bilinear systems. The main goal is to extend the essentials of linear theory to some nonlinear classes of problems.

Catmull-Rom Curve Fitting and Interpolation Equations

ERIC Educational Resources Information Center

Jerome, Lawrence

2010-01-01

Computer graphics and animation experts have been using the Catmull-Rom smooth curve interpolation equations since 1974, but the vector and matrix equations can be derived and simplified using basic algebra, resulting in a simple set of linear equations with constant coefficients. A variety of uses of Catmull-Rom interpolation are demonstrated,…

Implementing a Redesign Strategy: Lessons from Educational Change.

ERIC Educational Resources Information Center

Basom, Richard E., Jr.; Crandall, David P.

The effective implementation of school redesign, based on a social systems approach, is discussed in this paper. A basic assumption is that the interdependence of system elements has implications for a complex change process. Seven barriers to redesign and five critical issues for successful redesign strategy are presented. Seven linear steps for…

The Rolling Can Investigation: Towards an Explanation

ERIC Educational Resources Information Center

Ireson, Gren; Twidle, John

2005-01-01

This paper presents a context lead approach to rotational dynamics. By using nothing more than two cans of cola the basic notions of linear velocity, angular velocity, moments of inertia and conservation of energy can be explored. The approach can be used equally well as both a demonstration or an investigative assignment. The same starting point…

SPAR reference manual

NASA Technical Reports Server (NTRS)

Whetstone, W. D.

1976-01-01

The functions and operating rules of the SPAR system, which is a group of computer programs used primarily to perform stress, buckling, and vibrational analyses of linear finite element systems, were given. The following subject areas were discussed: basic information, structure definition, format system matrix processors, utility programs, static solutions, stresses, sparse matrix eigensolver, dynamic response, graphics, and substructure processors.

A Tale of Two Masses

ERIC Educational Resources Information Center

Bryan, Kurt

2011-01-01

This article presents an application of standard undergraduate ODE techniques to a modern engineering problem, that of using a tuned mass damper to control the vibration of a skyscraper. This material can be used in any ODE course in which the students have been familiarized with basic spring-mass models, resonance, and linear systems of ODEs.…

Skeletal muscle is a biological example of a linear electroactive actuator

NASA Astrophysics Data System (ADS)

Lieber, Richard L.

1999-05-01

Skeletal muscle represents a classic biological example of a structure-function relationship. This paper reviews basic muscle anatomy and demonstrates how molecular motion on the order of nm distances is converted into the macroscopic movements that are possible with skeletal muscle. Muscle anatomy provides a structural basis for understanding the basic mechanical properties of skeletal muscle -- namely, the length-tension relationship and the force-velocity relationships. The length-tension relationship illustrates that muscle force generation is extremely length dependent due to the interdigitation of the contractile filaments. The force-velocity relationship is characterized by a rapid force drop in muscle with increasing shortening velocity and a rapid rise in force when muscles are forced to lengthen. Finally, muscle architecture -- the number and arrangement of muscle fibers -- has a profound effect on the magnitude of muscle force generated and the magnitude of muscle excursion. These concepts demonstrate the elegant manner in which muscle acts as a biologically regenerating linear motor. These concepts can be used in developing artificial muscles as well as in performing surgical reconstructive procedures with various donor muscles.

Speed scanning system based on solid-state microchip laser for architectural planning

NASA Astrophysics Data System (ADS)

Redka, Dmitriy; Grishkanich, Alexsandr S.; Kolmakov, Egor; Tsvetkov, Konstantin

2017-10-01

According to the current great interest concerning Large-Scale Metrology applications in many different fields of manufacturing industry, technologies and techniques for dimensional measurement have recently shown a substantial improvement. Ease-of-use, logistic and economic issues, as well as metrological performance, are assuming a more and more important role among system requirements. The project is planned to conduct experimental studies aimed at identifying the impact of the application of the basic laws of microlasers as radiators on the linear-angular characteristics of existing measurement systems. The project is planned to conduct experimental studies aimed at identifying the impact of the application of the basic laws of microlasers as radiators on the linear-angular characteristics of existing measurement systems. The system consists of a distributed network-based layout, whose modularity allows to fit differently sized and shaped working volumes by adequately increasing the number of sensing units. Differently from existing spatially distributed metrological instruments, the remote sensor devices are intended to provide embedded data elaboration capabilities, in order to share the overall computational load.

Coordinate measuring system based on microchip lasers for reverse prototyping

NASA Astrophysics Data System (ADS)

Iakovlev, Alexey; Grishkanich, Alexsandr S.; Redka, Dmitriy; Tsvetkov, Konstantin

2017-02-01

According to the current great interest concerning Large-Scale Metrology applications in many different fields of manufacturing industry, technologies and techniques for dimensional measurement have recently shown a substantial improvement. Ease-of-use, logistic and economic issues, as well as metrological performance, are assuming a more and more important role among system requirements. The project is planned to conduct experimental studies aimed at identifying the impact of the application of the basic laws of chip and microlasers as radiators on the linear-angular characteristics of existing measurement systems. The project is planned to conduct experimental studies aimed at identifying the impact of the application of the basic laws of microlasers as radiators on the linear-angular characteristics of existing measurement systems. The system consists of a distributed network-based layout, whose modularity allows to fit differently sized and shaped working volumes by adequately increasing the number of sensing units. Differently from existing spatially distributed metrological instruments, the remote sensor devices are intended to provide embedded data elaboration capabilities, in order to share the overall computational load.

Comparisons of Multilevel Modeling and Structural Equation Modeling Approaches to Actor-Partner Interdependence Model.

PubMed

Hong, Sehee; Kim, Soyoung

2018-01-01

There are basically two modeling approaches applicable to analyzing an actor-partner interdependence model: the multilevel modeling (hierarchical linear model) and the structural equation modeling. This article explains how to use these two models in analyzing an actor-partner interdependence model and how these two approaches work differently. As an empirical example, marital conflict data were used to analyze an actor-partner interdependence model. The multilevel modeling and the structural equation modeling produced virtually identical estimates for a basic model. However, the structural equation modeling approach allowed more realistic assumptions on measurement errors and factor loadings, rendering better model fit indices.

Non-Linear Effects in Knowledge Production

NASA Astrophysics Data System (ADS)

Purica, Ionut

2007-04-01

The generation of technological knowledge is paramount to our present development; the production of technological knowledge is governed by the same Cobb Douglas type model, with the means of research and the intelligence level replacing capital, respectively labor. We are exploring the basic behavior of present days' economies that are producing technological knowledge, along with the `usual' industrial production and determine a basic behavior that turns out to be a `Henon attractor'. Measures are introduced for the gain of technological knowledge and for the information of technological sequences that are based respectively on the underlying multi-valued modal logic of the technological research and on nonlinear thermodynamic considerations.

Microscopy basics and the study of actin-actin-binding protein interactions.

PubMed

Thomasson, Maggie S; Macnaughtan, Megan A

2013-12-15

Actin is a multifunctional eukaryotic protein with a globular monomer form that polymerizes into a thin, linear microfilament in cells. Through interactions with various actin-binding proteins (ABPs), actin plays an active role in many cellular processes, such as cell motility and structure. Microscopy techniques are powerful tools for determining the role and mechanism of actin-ABP interactions in these processes. In this article, we describe the basic concepts of fluorescent speckle microscopy, total internal reflection fluorescence microscopy, atomic force microscopy, and cryoelectron microscopy and review recent studies that utilize these techniques to visualize the binding of actin with ABPs. Copyright © 2013 Elsevier Inc. All rights reserved.

A Theoretical Understanding of Circular Polarization Memory in Random Media

NASA Astrophysics Data System (ADS)

Dark, Julia

Radiative transport theory describes the propagation of light in random media that absorb, scatter, and emit radiation. To describe the propagation of light, the full polarization state is quantified using the Stokes parameters. For the sake of mathematical convenience, the polarization state of light is often neglected leading to the scalar radiative transport equation for the intensity only. For scalar transport theory, there is a well-established body of literature on numerical and analytic approximations to the radiative transport equation. We extend the scalar theory to the vector radiative transport equation (vRTE). In particular, we are interested in the theoretical basis for a phenomena called circular polarization memory. Circular polarization memory is the physical phenomena whereby circular polarization retains its ellipticity and handedness when propagating in random media. This is in contrast to the propagation of linear polarization in random media, which depolarizes at a faster rate, and specular reflection of circular polarization, whereby the circular polarization handedness flips. We investigate two limits that are of known interest in the phenomena of circular polarization memory. The first limit we investigate is that of forward-peaked scattering, i.e. the limit where most scattering events occur in the forward or near-forward directions. The second limit we consider is that of strong scattering and weak absorption. In the forward-peaked scattering limit we approximate the vRTE by a system of partial differential equations motivated by the scalar Fokker-Planck approximation. We call the leading order approximation the vector Fokker-Planck approximation. The vector Fokker Planck approximation predicts that strongly forward-peaked media exhibit circular polarization memory where the strength of the effect can be calculated from the expansion of the scattering matrix in special functions. In addition, we find in this limit that total intensity, linear polarization, and circular polarization decouple. From this result we conclude, that in the Fokker-Planck limit the scalar approximation is an appropriate leading order approximation. In the strong scattering and weak absorbing limit the vector radiative transport equation can be analyzed using boundary layer theory. In this case, the problem of light scattering in an optically thick medium is reduced to a 1D vRTE near the boundary and a 3D diffusion equation in the interior. We develop and implement a numerical solver for the boundary layer problem by using a discrete ordinate solver in the boundary layer and a spectral method to solve the diffusion approximation in the interior. We implement the method in Fortran 95 with external dependencies on BLAS, LAPACK, and FFTW. By analyzing the spectrum of the discretized vRTE in the boundary layer, we are able to predict the presence of circular polarization memory in a given medium.

Improving biomedical information retrieval by linear combinations of different query expansion techniques.

PubMed

Abdulla, Ahmed AbdoAziz Ahmed; Lin, Hongfei; Xu, Bo; Banbhrani, Santosh Kumar

2016-07-25

Biomedical literature retrieval is becoming increasingly complex, and there is a fundamental need for advanced information retrieval systems. Information Retrieval (IR) programs scour unstructured materials such as text documents in large reserves of data that are usually stored on computers. IR is related to the representation, storage, and organization of information items, as well as to access. In IR one of the main problems is to determine which documents are relevant and which are not to the user's needs. Under the current regime, users cannot precisely construct queries in an accurate way to retrieve particular pieces of data from large reserves of data. Basic information retrieval systems are producing low-quality search results. In our proposed system for this paper we present a new technique to refine Information Retrieval searches to better represent the user's information need in order to enhance the performance of information retrieval by using different query expansion techniques and apply a linear combinations between them, where the combinations was linearly between two expansion results at one time. Query expansions expand the search query, for example, by finding synonyms and reweighting original terms. They provide significantly more focused, particularized search results than do basic search queries. The retrieval performance is measured by some variants of MAP (Mean Average Precision) and according to our experimental results, the combination of best results of query expansion is enhanced the retrieved documents and outperforms our baseline by 21.06 %, even it outperforms a previous study by 7.12 %. We propose several query expansion techniques and their combinations (linearly) to make user queries more cognizable to search engines and to produce higher-quality search results.

Plant uptake of elements in soil and pore water: field observations versus model assumptions.

PubMed

Raguž, Veronika; Jarsjö, Jerker; Grolander, Sara; Lindborg, Regina; Avila, Rodolfo

2013-09-15

Contaminant concentrations in various edible plant parts transfer hazardous substances from polluted areas to animals and humans. Thus, the accurate prediction of plant uptake of elements is of significant importance. The processes involved contain many interacting factors and are, as such, complex. In contrast, the most common way to currently quantify element transfer from soils into plants is relatively simple, using an empirical soil-to-plant transfer factor (TF). This practice is based on theoretical assumptions that have been previously shown to not generally be valid. Using field data on concentrations of 61 basic elements in spring barley, soil and pore water at four agricultural sites in mid-eastern Sweden, we quantify element-specific TFs. Our aim is to investigate to which extent observed element-specific uptake is consistent with TF model assumptions and to which extent TF's can be used to predict observed differences in concentrations between different plant parts (root, stem and ear). Results show that for most elements, plant-ear concentrations are not linearly related to bulk soil concentrations, which is congruent with previous studies. This behaviour violates a basic TF model assumption of linearity. However, substantially better linear correlations are found when weighted average element concentrations in whole plants are used for TF estimation. The highest number of linearly-behaving elements was found when relating average plant concentrations to soil pore-water concentrations. In contrast to other elements, essential elements (micronutrients and macronutrients) exhibited relatively small differences in concentration between different plant parts. Generally, the TF model was shown to work reasonably well for micronutrients, whereas it did not for macronutrients. The results also suggest that plant uptake of elements from sources other than the soil compartment (e.g. from air) may be non-negligible. Copyright © 2013 Elsevier Ltd. All rights reserved.

Protection of Workers and Third Parties during the Construction of Linear Structures

NASA Astrophysics Data System (ADS)

Vlčková, Jitka; Venkrbec, Václav; Henková, Svatava; Chromý, Adam

2017-12-01

The minimization of risk in the workplace through a focus on occupational health and safety (OHS) is one of the primary objectives for every construction project. The most serious accidents in the construction industry occur during work on earthworks and linear structures. The character of such structures places them among those posing the greatest threat to the public (referred to as “third parties”). They can be characterized as large structures whose construction may involve the building site extending in a narrow lane alongside previously constructed objects currently in use by the public. Linear structures are often directly connected to existing objects or buildings, making it impossible to guard the whole construction site. However, many OHS problems related to linear structures can be prevented during the design stage. The aim of this article is to introduce a new methodology which has been implemented into a computer program that deals with safety measures at construction sites where work is performed on linear structures. Based on existing experience with the design of such structures and their execution and supervision by safety coordinators, the basic types of linear structures, their location in the terrain, the conditions present during their execution and other marginal conditions and influences were modelled. Basic safety information has been assigned to this elementary information, which is strictly necessary for the construction process. The safety provisions can be grouped according to type, e.g. technical, organizational and other necessary documentation, or into sets of provisions concerning areas such as construction site safety, transport safety, earthworks safety, etc. The selection of the given provisions takes place using multiple criteria. The aim of creating this program is to provide a practical tool for designers, contractors and construction companies. The model can contribute to the sufficient awareness of these participants about technical and organizational provisions that can help them to meet workplace safety requirements. The software for the selection of safety provisions also contains module that can calculate necessary cost estimates using a calculation formula chosen by the user. All software data conform to European standards harmonized for the Czech Republic.

Principles of Induction Accelerators

NASA Astrophysics Data System (ADS)

Briggs*, Richard J.

The basic concepts involved in induction accelerators are introduced in this chapter. The objective is to provide a foundation for the more detailed coverage of key technology elements and specific applications in the following chapters. A wide variety of induction accelerators are discussed in the following chapters, from the high current linear electron accelerator configurations that have been the main focus of the original developments, to circular configurations like the ion synchrotrons that are the subject of more recent research. The main focus in the present chapter is on the induction module containing the magnetic core that plays the role of a transformer in coupling the pulsed power from the modulator to the charged particle beam. This is the essential common element in all these induction accelerators, and an understanding of the basic processes involved in its operation is the main objective of this chapter. (See [1] for a useful and complementary presentation of the basic principles in induction linacs.)

The Goertler vortex instability mechanism in three-dimensional boundary layers

NASA Technical Reports Server (NTRS)

Hall, P.

1984-01-01

The two dimensional boundary layer on a concave wall is centrifugally unstable with respect to vortices aligned with the basic flow for sufficiently high values of the Goertler number. However, in most situations of practical interest the basic flow is three dimensional and previous theoretical investigations do not apply. The linear stability of the flow over an infinitely long swept wall of variable curvature is considered. If there is no pressure gradient in the boundary layer the instability problem can always be related to an equivalent two dimensional calculation. However, in general, this is not the case and even for small values of the crossflow velocity field dramatic differences between the two and three dimensional problems emerge. When the size of the crossflow is further increased, the vortices in the neutral location have their axes locally perpendicular to the vortex lines of the basic flow.

Novel programmable microwave photonic filter with arbitrary filtering shape and linear phase.

PubMed

Zhu, Xiaoqi; Chen, Feiya; Peng, Huanfa; Chen, Zhangyuan

2017-04-17

We propose and demonstrate a novel optical frequency comb (OFC) based microwave photonic filter which is able to realize arbitrary filtering shape with linear phase response. The shape of filter response is software programmable using finite impulse response (FIR) filter design method. By shaping the OFC spectrum using a programmable waveshaper, we can realize designed amplitude of FIR taps. Positive and negative sign of FIR taps are achieved by balanced photo-detection. The double sideband (DSB) modulation and symmetric distribution of filter taps are used to maintain the linear phase condition. In the experiment, we realize a fully programmable filter in the range from DC to 13.88 GHz. Four basic types of filters (lowpass, highpass, bandpass and bandstop) with different bandwidths, cut-off frequencies and central frequencies are generated. Also a triple-passband filter is realized in our experiment. To the best of our knowledge, it is the first demonstration of a programmable multiple passband MPF with linear phase response. The experiment shows good agreement with the theoretical result.

A Linear Programming Approach to Routing Control in Networks of Constrained Nonlinear Positive Systems with Concave Flow Rates

NASA Technical Reports Server (NTRS)

Arneson, Heather M.; Dousse, Nicholas; Langbort, Cedric

2014-01-01

We consider control design for positive compartmental systems in which each compartment's outflow rate is described by a concave function of the amount of material in the compartment.We address the problem of determining the routing of material between compartments to satisfy time-varying state constraints while ensuring that material reaches its intended destination over a finite time horizon. We give sufficient conditions for the existence of a time-varying state-dependent routing strategy which ensures that the closed-loop system satisfies basic network properties of positivity, conservation and interconnection while ensuring that capacity constraints are satisfied, when possible, or adjusted if a solution cannot be found. These conditions are formulated as a linear programming problem. Instances of this linear programming problem can be solved iteratively to generate a solution to the finite horizon routing problem. Results are given for the application of this control design method to an example problem. Key words: linear programming; control of networks; positive systems; controller constraints and structure.

Deconvolutions based on singular value decomposition and the pseudoinverse: a guide for beginners.

PubMed

Hendler, R W; Shrager, R I

1994-01-01

Singular value decomposition (SVD) is deeply rooted in the theory of linear algebra, and because of this is not readily understood by a large group of researchers who could profit from its application. In this paper, we discuss the subject on a level that should be understandable to scientists who are not well versed in linear algebra. However, because it is necessary that certain key concepts in linear algebra be appreciated in order to comprehend what is accomplished by SVD, we present the section, 'Bare basics of linear algebra'. This is followed by a discussion of the theory of SVD. Next we present step-by-step examples to illustrate how SVD is applied to deconvolute a titration involving a mixture of three pH indicators. One noiseless case is presented as well as two cases where either a fixed or varying noise level is present. Finally, we discuss additional deconvolutions of mixed spectra based on the use of the pseudoinverse.

Grouping and emergent features in vision: toward a theory of basic Gestalts.

PubMed

Pomerantz, James R; Portillo, Mary C

2011-10-01

Gestalt phenomena are often so powerful that mere demonstrations can confirm their existence, but Gestalts have proven hard to define and measure. Here we outline a theory of basic Gestalts (TBG) that defines Gestalts as emergent features (EFs). The logic relies on discovering wholes that are more discriminable than are the parts from which they are built. These wholes contain EFs that can act as basic features in human vision. As context is added to a visual stimulus, a hierarchy of EFs appears. Starting with a single dot and adding a second yields the first two potential EFs: the proximity (distance) and orientation (angle) between the two dots. A third dot introduces two more potential EFs: symmetry and linearity; a fourth dot produces surroundedness. This hierarchy may extend to collinearity, parallelism, closure, and more. We use the magnitude of Configural Superiority Effects to measure the salience of EFs on a common scale, potentially letting us compare the strengths of various grouping principles. TBG appears promising, with our initial experiments establishing and quantifying at least three basic EFs in human vision.

A density functional theory study of the correlation between analyte basicity, ZnPc adsorption strength, and sensor response.

PubMed

Tran, N L; Bohrer, F I; Trogler, W C; Kummel, A C

2009-05-28

Density functional theory (DFT) simulations were used to determine the binding strength of 12 electron-donating analytes to the zinc metal center of a zinc phthalocyanine molecule (ZnPc monomer). The analyte binding strengths were compared to the analytes' enthalpies of complex formation with boron trifluoride (BF(3)), which is a direct measure of their electron donating ability or Lewis basicity. With the exception of the most basic analyte investigated, the ZnPc binding energies were found to correlate linearly with analyte basicities. Based on natural population analysis calculations, analyte complexation to the Zn metal of the ZnPc monomer resulted in limited charge transfer from the analyte to the ZnPc molecule, which increased with analyte-ZnPc binding energy. The experimental analyte sensitivities from chemiresistor ZnPc sensor data were proportional to an exponential of the binding energies from DFT calculations consistent with sensitivity being proportional to analyte coverage and binding strength. The good correlation observed suggests DFT is a reliable method for the prediction of chemiresistor metallophthalocyanine binding strengths and response sensitivities.

A multiple linear regression analysis of hot corrosion attack on a series of nickel base turbine alloys

NASA Technical Reports Server (NTRS)

Barrett, C. A.

1985-01-01

Multiple linear regression analysis was used to determine an equation for estimating hot corrosion attack for a series of Ni base cast turbine alloys. The U transform (i.e., 1/sin (% A/100) to the 1/2) was shown to give the best estimate of the dependent variable, y. A complete second degree equation is described for the centered" weight chemistries for the elements Cr, Al, Ti, Mo, W, Cb, Ta, and Co. In addition linear terms for the minor elements C, B, and Zr were added for a basic 47 term equation. The best reduced equation was determined by the stepwise selection method with essentially 13 terms. The Cr term was found to be the most important accounting for 60 percent of the explained variability hot corrosion attack.

Detector noise statistics in the non-linear regime

NASA Technical Reports Server (NTRS)

Shopbell, P. L.; Bland-Hawthorn, J.

1992-01-01

The statistical behavior of an idealized linear detector in the presence of threshold and saturation levels is examined. It is assumed that the noise is governed by the statistical fluctuations in the number of photons emitted by the source during an exposure. Since physical detectors cannot have infinite dynamic range, our model illustrates that all devices have non-linear regimes, particularly at high count rates. The primary effect is a decrease in the statistical variance about the mean signal due to a portion of the expected noise distribution being removed via clipping. Higher order statistical moments are also examined, in particular, skewness and kurtosis. In principle, the expected distortion in the detector noise characteristics can be calibrated using flatfield observations with count rates matched to the observations. For this purpose, some basic statistical methods that utilize Fourier analysis techniques are described.

The Development of Embodied Representations of Numerical Understanding through Gameplay

ERIC Educational Resources Information Center

Clark, Colin Travis

2012-01-01

Young children must develop basic concepts of numeracy--one being that numbers have magnitudes that increase linearly--before they are able to succeed in mathematics. Children from low-income families have been found to be at a greater disadvantage in the development of numeracy, but this disadvantage can be overcome through the use of a simple…

Solution-adaptive finite element method in computational fracture mechanics

NASA Technical Reports Server (NTRS)

Min, J. B.; Bass, J. M.; Spradley, L. W.

1993-01-01

Some recent results obtained using solution-adaptive finite element method in linear elastic two-dimensional fracture mechanics problems are presented. The focus is on the basic issue of adaptive finite element method for validating the applications of new methodology to fracture mechanics problems by computing demonstration problems and comparing the stress intensity factors to analytical results.

First Principles Modeling of the Performance of a Hydrogen-Peroxide-Driven Chem-E-Car

ERIC Educational Resources Information Center

Farhadi, Maryam; Azadi, Pooya; Zarinpanjeh, Nima

2009-01-01

In this study, performance of a hydrogen-peroxide-driven car has been simulated using basic conservation laws and a few numbers of auxiliary equations. A numerical method was implemented to solve sets of highly non-linear ordinary differential equations. Transient pressure and the corresponding traveled distance for three different car weights are…

Evaluating an Experimental Audio-Visual Module Programmed to Teach a Basic Anatomical and Physiological System.

ERIC Educational Resources Information Center

Federico, Pat-Anthony

The learning efficiency and effectiveness of teaching an anatomical and physiological system to Air Force enlisted trainees utilizing an experimental audiovisual programed module was compared to that of a commercial linear programed text. It was demonstrated that the audiovisual programed approach to training was more efficient than and equally as…

Computational Performance of Group IV Personnel in Vocational Training Programs. Final Report.

ERIC Educational Resources Information Center

Main, Ray E.; Harrigan, Robert J.

The document evaluates Navy Group Four personnel gains in basic arithmetic skills after taking experimental courses in linear measurement and recipe conversion. Categorized as Mental Group Four by receiving scores from the 10th to the 30th percentile of the Armed Forces Qualification Test, trainees received instruction tailored to the level of…

The Convergence Model of Communication. Papers of the East-West Communication Institute, No. 18.

ERIC Educational Resources Information Center

Kincaid, D. Lawrence

Expressing the need for a description of communication that is equally applicable to all the social sciences, this report develops a general model of the communication process based upon the principle of convergence as derived from basic information theory and cybernetics. It criticizes the linear, one-way models of communication that have…

Functional Thinking Ways in Relation to Linear Function Tables of Elementary School Students

ERIC Educational Resources Information Center

Tanisli, Dilek

2011-01-01

One of the basic components of algebraic thinking is functional thinking. Functional thinking involves focusing on the relationship between two (or more) varying quantities and such thinking facilitates the studies on both algebra and the notion of function. The development of functional thinking of students should start in the early grades and it…

Mathematics. Unit 6: A Core Curriculum of Related Instruction for Apprentices.

ERIC Educational Resources Information Center

New York State Education Dept., Albany. Bureau of Occupational and Career Curriculum Development.

The mathematics unit is presented to assist apprentices to acquire a general knowledge of mathematic skills. The unit consists of nine modules: (1) basic addition, subtraction, multiplication, and division; (2) conventional linear measure; (3) using the metric system, (4) steps to take in solving problems, (5) how to calculate areas and volumes,…

A microcomputer program for analysis of nucleic acid hybridization data

PubMed Central

Green, S.; Field, J.K.; Green, C.D.; Beynon, R.J.

1982-01-01

The study of nucleic acid hybridization is facilitated by computer mediated fitting of theoretical models to experimental data. This paper describes a non-linear curve fitting program, using the `Patternsearch' algorithm, written in BASIC for the Apple II microcomputer. The advantages and disadvantages of using a microcomputer for local data processing are discussed. Images PMID:7071017

Flapping response characteristics of hingeless rotor blades by a gereralized harmonic balance method

NASA Technical Reports Server (NTRS)

Peters, D. A.; Ormiston, R. A.

1975-01-01

Linearized equations of motion for the flapping response of flexible rotor blades in forward flight are derived in terms of generalized coordinates. The equations are solved using a matrix form of the method of linear harmonic balance, yielding response derivatives for each harmonic of the blade deformations and of the hub forces and moments. Numerical results and approximate closed-form expressions for rotor derivatives are used to illustrate the relationships between rotor parameters, modeling assumptions, and rotor response characteristics. Finally, basic hingeless rotor response derivatives are presented in tabular and graphical form for a wide range of configuration parameters and operating conditions.

Chua's Equation was Proved to BE Chaotic in Two Years, Lorenz Equation in Thirty Six Years

NASA Astrophysics Data System (ADS)

Muthuswamy, Bharathwaj

2013-01-01

Although there are probably more publications on Chua's circuit than any other chaotic circuit, a tutorial with a historical emphasis is still lacking. Hence the goal of this chapter is to provide such a tutorial. This chapter will prove useful for a novice who is looking to understand the basics behind chaotic circuits without too much technical details. The chapter also includes a cookbook approach to a rigorous proof of chaos in piecewise-linear systems. The proof is a summary of the original piecewise-linear proof of chaos in Chua's circuit. The chapter concludes with a discussion of circuits derived from Chua's circuit.

On the numerical treatment of nonlinear source terms in reaction-convection equations

NASA Technical Reports Server (NTRS)

Lafon, A.; Yee, H. C.

1992-01-01

The objectives of this paper are to investigate how various numerical treatments of the nonlinear source term in a model reaction-convection equation can affect the stability of steady-state numerical solutions and to show under what conditions the conventional linearized analysis breaks down. The underlying goal is to provide part of the basic building blocks toward the ultimate goal of constructing suitable numerical schemes for hypersonic reacting flows, combustions and certain turbulence models in compressible Navier-Stokes computations. It can be shown that nonlinear analysis uncovers much of the nonlinear phenomena which linearized analysis is not capable of predicting in a model reaction-convection equation.

Ionic liquids as transesterification catalysts: applications for the synthesis of linear and cyclic organic carbonates

PubMed Central

Perosa, Alvise; Guidi, Sandro; Cattelan, Lisa

2016-01-01

Summary The use of ionic liquids (ILs) as organocatalysts is reviewed for transesterification reactions, specifically for the conversion of nontoxic compounds such as dialkyl carbonates to both linear mono-transesterification products or alkylene carbonates. An introductory survey compares pros and cons of classic catalysts based on both acidic and basic systems, to ionic liquids. Then, innovative green syntheses of task-specific ILs and their representative applications are introduced to detail the efficiency and highly selective outcome of ILs-catalyzed transesterification reactions. A mechanistic hypothesis is discussed by the concept of cooperative catalysis based on the dual (electrophilic/nucleophilic) activation of reactants. PMID:27829898

Cosmic-ray streaming perpendicular to the mean magnetic field. II - The gyrophase distribution function

NASA Technical Reports Server (NTRS)

Forman, M. A.; Jokipii, J. R.

1978-01-01

The distribution function of cosmic rays streaming perpendicular to the mean magnetic field in a turbulent medium is reexamined. Urch's (1977) discovery that in quasi-linear theory, the flux is due to particles at 90 deg pitch angle is discussed and shown to be consistent with previous formulations of the theory. It is pointed out that this flux of particles at 90 deg cannot be arbitrarily set equal to zero, and hence the alternative theory which proceeds from this premise is dismissed. A further, basic inconsistency in Urch's transport equation is demonstrated, and the connection between quasi-linear theory and compound diffusion is discussed.

Toward intelligent information sysytem

NASA Astrophysics Data System (ADS)

Onodera, Natsuo

"Hypertext" means a concept of a novel computer-assisted tool for storage and retrieval of text information based on human association. Structure of knowledge in our idea processing is generally complicated and networked, but traditional paper documents merely express it in essentially linear and sequential forms. However, recent advances in work-station technology have allowed us to process easily electronic documents containing non-linear structure such as references or hierarchies. This paper describes concept, history and basic organization of hypertext, and shows the outline and features of existing main hypertext systems. Particularly, use of the hypertext database is illustrated by an example of Intermedia developed by Brown University.

Exact solution of some linear matrix equations using algebraic methods

NASA Technical Reports Server (NTRS)

Djaferis, T. E.; Mitter, S. K.

1977-01-01

A study is done of solution methods for Linear Matrix Equations including Lyapunov's equation, using methods of modern algebra. The emphasis is on the use of finite algebraic procedures which are easily implemented on a digital computer and which lead to an explicit solution to the problem. The action f sub BA is introduced a Basic Lemma is proven. The equation PA + BP = -C as well as the Lyapunov equation are analyzed. Algorithms are given for the solution of the Lyapunov and comment is given on its arithmetic complexity. The equation P - A'PA = Q is studied and numerical examples are given.

HEAVY ION LINEAR ACCELERATOR

DOEpatents

Van Atta, C.M.; Beringer, R.; Smith, L.

1959-01-01

A linear accelerator of heavy ions is described. The basic contributions of the invention consist of a method and apparatus for obtaining high energy particles of an element with an increased charge-to-mass ratio. The method comprises the steps of ionizing the atoms of an element, accelerating the resultant ions to an energy substantially equal to one Mev per nucleon, stripping orbital electrons from the accelerated ions by passing the ions through a curtain of elemental vapor disposed transversely of the path of the ions to provide a second charge-to-mass ratio, and finally accelerating the resultant stripped ions to a final energy of at least ten Mev per nucleon.

Resonant soft X-ray scattering study of twist bend nematic, cholesteric and blue phases.

NASA Astrophysics Data System (ADS)

Slamonczyk, Miroslaw; Grecka, Ewa; Vaupotic, Natasa; Pociecha, Damian; Gleesom, Jim; Jakli, Antal; Sprunt, Sam; Wang, Cheng; Hexemer, Alexander; Zhu, Chenhui

We have demonstrated that, when operated at carbon K-edge, the linearly polarized soft X-rays can enable bond orientation sensitivity, which can be utilized to probe the otherwise forbidden peak from the helices of twist bend nematic and helical nanofilament phase. Here we show that the same principle can be used to probe blue phase and chiral nematic phase. Furthermore, we discuss the relationship between the incoming linearly polarized X-rays, and the anisotropy in the scattering pattern. Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02- 05CH11231.

Optoelectronic Reservoir Computing

PubMed Central

Paquot, Y.; Duport, F.; Smerieri, A.; Dambre, J.; Schrauwen, B.; Haelterman, M.; Massar, S.

2012-01-01

Reservoir computing is a recently introduced, highly efficient bio-inspired approach for processing time dependent data. The basic scheme of reservoir computing consists of a non linear recurrent dynamical system coupled to a single input layer and a single output layer. Within these constraints many implementations are possible. Here we report an optoelectronic implementation of reservoir computing based on a recently proposed architecture consisting of a single non linear node and a delay line. Our implementation is sufficiently fast for real time information processing. We illustrate its performance on tasks of practical importance such as nonlinear channel equalization and speech recognition, and obtain results comparable to state of the art digital implementations. PMID:22371825

Aesthetic perception of visual textures: a holistic exploration using texture analysis, psychological experiment, and perception modeling.

PubMed

Liu, Jianli; Lughofer, Edwin; Zeng, Xianyi

2015-01-01

Modeling human aesthetic perception of visual textures is important and valuable in numerous industrial domains, such as product design, architectural design, and decoration. Based on results from a semantic differential rating experiment, we modeled the relationship between low-level basic texture features and aesthetic properties involved in human aesthetic texture perception. First, we compute basic texture features from textural images using four classical methods. These features are neutral, objective, and independent of the socio-cultural context of the visual textures. Then, we conduct a semantic differential rating experiment to collect from evaluators their aesthetic perceptions of selected textural stimuli. In semantic differential rating experiment, eights pairs of aesthetic properties are chosen, which are strongly related to the socio-cultural context of the selected textures and to human emotions. They are easily understood and connected to everyday life. We propose a hierarchical feed-forward layer model of aesthetic texture perception and assign 8 pairs of aesthetic properties to different layers. Finally, we describe the generation of multiple linear and non-linear regression models for aesthetic prediction by taking dimensionality-reduced texture features and aesthetic properties of visual textures as dependent and independent variables, respectively. Our experimental results indicate that the relationships between each layer and its neighbors in the hierarchical feed-forward layer model of aesthetic texture perception can be fitted well by linear functions, and the models thus generated can successfully bridge the gap between computational texture features and aesthetic texture properties.

Developmental changes in emotion recognition from full-light and point-light displays of body movement.

PubMed

Ross, Patrick D; Polson, Louise; Grosbras, Marie-Hélène

2012-01-01

To date, research on the development of emotion recognition has been dominated by studies on facial expression interpretation; very little is known about children's ability to recognize affective meaning from body movements. In the present study, we acquired simultaneous video and motion capture recordings of two actors portraying four basic emotions (Happiness Sadness, Fear and Anger). One hundred and seven primary and secondary school children (aged 4-17) and 14 adult volunteers participated in the study. Each participant viewed the full-light and point-light video clips and was asked to make a forced-choice as to which emotion was being portrayed. As a group, children performed worse than adults for both point-light and full-light conditions. Linear regression showed that both age and lighting condition were significant predictors of performance in children. Using piecewise regression, we found that a bilinear model with a steep improvement in performance until 8.5 years of age, followed by a much slower improvement rate through late childhood and adolescence best explained the data. These findings confirm that, like for facial expression, adolescents' recognition of basic emotions from body language is not fully mature and seems to follow a non-linear development. This is in line with observations of non-linear developmental trajectories for different aspects of human stimuli processing (voices and faces), perhaps suggesting a shift from one perceptual or cognitive strategy to another during adolescence. These results have important implications to understanding the maturation of social cognition.

Some important considerations in the development of stress corrosion cracking test methods.

NASA Technical Reports Server (NTRS)

Wei, R. P.; Novak, S. R.; Williams, D. P.

1972-01-01

Discussion of some of the precaution needs the development of fracture-mechanics based test methods for studying stress corrosion cracking involves. Following a review of pertinent analytical fracture mechanics considerations and of basic test methods, the implications for test corrosion cracking studies of the time-to-failure determining kinetics of crack growth and life are examined. It is shown that the basic assumption of the linear-elastic fracture mechanics analyses must be clearly recognized and satisfied in experimentation and that the effects of incubation and nonsteady-state crack growth must also be properly taken into account in determining the crack growth kinetics, if valid data are to be obtained from fracture-mechanics based test methods.

Three-dimensional elliptic grid generation technique with application to turbomachinery cascades

NASA Technical Reports Server (NTRS)

Chen, S. C.; Schwab, J. R.

1988-01-01

Described is a numerical method for generating 3-D grids for turbomachinery computational fluid dynamic codes. The basic method is general and involves the solution of a quasi-linear elliptic partial differential equation via pointwise relaxation with a local relaxation factor. It allows specification of the grid point distribution on the boundary surfaces, the grid spacing off the boundary surfaces, and the grid orthogonality at the boundary surfaces. A geometry preprocessor constructs the grid point distributions on the boundary surfaces for general turbomachinery cascades. Representative results are shown for a C-grid and an H-grid for a turbine rotor. Two appendices serve as user's manuals for the basic solver and the geometry preprocessor.

Plasma myelin basic protein assay using Gilford enzyme immunoassay cuvettes.

PubMed

Groome, N P

1981-10-01

The assay of myelin basic protein in body fluids has potential clinical importance as a routine indicator of demyelination. Preliminary details of a competitive enzyme immunoassay for this protein have previously been published by the author (Groome, N. P. (1980) J. Neurochem. 35, 1409-1417). The present paper now describes the adaptation of this assay for use on human plasma and various aspects of routine data processing. A commercially available cuvette system was found to have advantages over microtitre plates but required a permuted arrangement of sample replicates for consistent results. For dose interpolation, the standard curve could be fitted to a three parameter non-linear equation by regression analysis or linearised by the logit/log transformation.

International Linear Collider Reference Design Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brau, James,; Okada, Yasuhiro,; Walker, Nicholas J.,

2007-08-13

{lg_bullet} What is the universe? How did it begin? {lg_bullet} What are matter and energy? What are space and time? These basic questions have been the subject of scientific theories and experiments throughout human history. The answers have revolutionized the enlightened view of the world, transforming society and advancing civilization. Universal laws and principles govern everyday phenomena, some of them manifesting themselves only at scales of time and distance far beyond everyday experience. Particle physics experiments using particle accelerators transform matter and energy, to reveal the basic workings of the universe. Other experiments exploit naturally occurring particles, such as solarmore » neutrinos or cosmic rays, and astrophysical observations, to provide additional insights.« less

Locally linear regression for pose-invariant face recognition.

PubMed

Chai, Xiujuan; Shan, Shiguang; Chen, Xilin; Gao, Wen

2007-07-01

The variation of facial appearance due to the viewpoint (/pose) degrades face recognition systems considerably, which is one of the bottlenecks in face recognition. One of the possible solutions is generating virtual frontal view from any given nonfrontal view to obtain a virtual gallery/probe face. Following this idea, this paper proposes a simple, but efficient, novel locally linear regression (LLR) method, which generates the virtual frontal view from a given nonfrontal face image. We first justify the basic assumption of the paper that there exists an approximate linear mapping between a nonfrontal face image and its frontal counterpart. Then, by formulating the estimation of the linear mapping as a prediction problem, we present the regression-based solution, i.e., globally linear regression. To improve the prediction accuracy in the case of coarse alignment, LLR is further proposed. In LLR, we first perform dense sampling in the nonfrontal face image to obtain many overlapped local patches. Then, the linear regression technique is applied to each small patch for the prediction of its virtual frontal patch. Through the combination of all these patches, the virtual frontal view is generated. The experimental results on the CMU PIE database show distinct advantage of the proposed method over Eigen light-field method.

Relationships between digital signal processing and control and estimation theory

NASA Technical Reports Server (NTRS)

Willsky, A. S.

1978-01-01

Research directions in the fields of digital signal processing and modern control and estimation theory are discussed. Stability theory, linear prediction and parameter identification, system synthesis and implementation, two-dimensional filtering, decentralized control and estimation, and image processing are considered in order to uncover some of the basic similarities and differences in the goals, techniques, and philosophy of the disciplines.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tessore, Nicolas; Metcalf, R. Benton; Winther, Hans A.

A number of alternatives to general relativity exhibit gravitational screening in the non-linear regime of structure formation. We describe a set of algorithms that can produce weak lensing maps of large scale structure in such theories and can be used to generate mock surveys for cosmological analysis. By analysing a few basic statistics we indicate how these alternatives can be distinguished from general relativity with future weak lensing surveys.

Helping Struggling Adolescent Readers: Is Implementation of Different Components of Scholastic's READ 180 Associated with Differences in Student Achievement Gains?

ERIC Educational Resources Information Center

Coffey, Debra J.

2013-01-01

This dissertation uses data from the evaluation of a Striving Readers project to examine the associations between levels of implementation of different components of Scholastic's "READ 180" and student achievement as measured on the Iowa Test of Basic Skills (ITBS) reading assessment. The approach was hierarchical linear modeling using…

An analysis of the multiple model adaptive control algorithm. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Greene, C. S.

1978-01-01

Qualitative and quantitative aspects of the multiple model adaptive control method are detailed. The method represents a cascade of something which resembles a maximum a posteriori probability identifier (basically a bank of Kalman filters) and a bank of linear quadratic regulators. Major qualitative properties of the MMAC method are examined and principle reasons for unacceptable behavior are explored.

Arbitrary amplitude nucleus-acoustic solitons in multi-ion quantum plasmas with relativistically degenerate electrons

NASA Astrophysics Data System (ADS)

Sultana, S.; Schlickeiser, R.

2018-02-01

A three component degenerate relativistic quantum plasma (consisting of relativistically degenerate electrons, nondegenerate inertial light nuclei, and stationary heavy nuclei) is considered to model the linear wave and also the electrostatic solitary waves in the light nuclei-scale length. A well-known normal mode analysis is employed to investigate the linear wave properties. A mechanical-motion analog (Sagdeev-type) pseudo-potential approach, which reveals the existence of large amplitude solitary excitations, is adopted to study the nonlinear wave properties. Only the positive potential solitary excitations are found to exist in the plasma medium under consideration. The basic properties of the arbitrary amplitude electrostatic acoustic modes in the light nuclei-scale length and their existence domain in terms of soliton speed (Mach number) are examined. The modifications of solitary wave characteristics and their existence domain with the variation of different key plasma configuration parameters (e.g., electrons degeneracy parameter, inertial light nuclei number density, and degenerate electron number density) are also analyzed. Our results, which may be helpful to explain the basic features of the nonlinear wave propagation in multi-component degenerate quantum plasmas, in connection with astrophysical compact objects (e.g., white dwarfs) are briefly discussed.

Development of a 3D CZT detector prototype for Laue Lens telescope

NASA Astrophysics Data System (ADS)

Caroli, Ezio; Auricchio, Natalia; Del Sordo, Stefano; Abbene, Leonardo; Budtz-Jørgensen, Carl; Casini, Fabio; Curado da Silva, Rui M.; Kuvvetlli, Irfan; Milano, Luciano; Natalucci, Lorenzo; Quadrini, Egidio M.; Stephen, John B.; Ubertini, Pietro; Zanichelli, Massimiliano; Zappettini, Andrea

2010-07-01

We report on the development of a 3D position sensitive prototype suitable as focal plane detector for Laue lens telescope. The basic sensitive unit is a drift strip detector based on a CZT crystal, (~19×8 mm2 area, 2.4 mm thick), irradiated transversally to the electric field direction. The anode side is segmented in 64 strips, that divide the crystal in 8 independent sensor (pixel), each composed by one collecting strip and 7 (one in common) adjacent drift strips. The drift strips are biased by a voltage divider, whereas the anode strips are held at ground. Furthermore, the cathode is divided in 4 horizontal strips for the reconstruction of the third interaction position coordinate. The 3D prototype will be made by packing 8 linear modules, each composed by one basic sensitive unit, bonded on a ceramic layer. The linear modules readout is provided by a custom front end electronics implementing a set of three RENA-3 for a total of 128 channels. The front-end electronics and the operating logics (in particular coincidence logics for polarisation measurements) are handled by a versatile and modular multi-parametric back end electronics developed using FPGA technology.

Production of Medical Isotopes with Electron Linacs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rotsch, D A; Alford, K.; Bailey, J. L.

Radioisotopes play important roles in numerous areas ranging from medical treatments to national security and basic research. Radionuclide production technology for medical applications has been pursued since the early 1900s both commercially and in nuclear science centers. Many medical isotopes are now in routine production and are used in day-to-day medical procedures. Despite these advancements, research is accelerating around the world to improve the existing production methodologies as well as to develop novel radionuclides for new medical appli-cations. Electron linear accelerators (linacs) represent a unique method for the production of radioisotopes. Even though the basic technology has been around formore » decades, only recently have electron linacs capable of producing photons with sufficient energy and flux for radioisotope production become available. Housed in Argonne Nation-al Laboratory’s Low Energy Accelerator Facility (LEAF) is a newly upgraded 55 MeV/25-kW electron linear ac-celerator, capable of producing a wide range of radioiso-topes. This talk will focus on the work being performed for the production of the medical isotopes 99Mo (99Mo/99mTc generator), 67Cu, and 47Sc.« less

The performance of Geiger mode avalanche photo-diodes in free space laser communication links

NASA Astrophysics Data System (ADS)

Farrell, Thomas C.

2018-05-01

Geiger mode avalanche photo-diode (APD) arrays, when used as detectors in laser communication (lasercom) receivers, promise better performance at lower signal levels than APDs operated in the linear mode. In this paper, we describe the basic operation of the Geiger mode APD array as a lasercom detector, concentrating on aspects relevant to the link design engineer (rather than, for example, describing the details of the physics of the basic device operation itself). Equations are developed that describe the effects of defocus and hold-off time on the relation between the number of photons detected by the array and the output of photo-electron counts. We show how to incorporate these equations into a link budget. The resulting predictions are validated by comparison against simulation results. Finally, we compare the performance of linear mode APD based receivers and Geiger mode APD array based receivers. Results show the Geiger mode receivers yield better performance, in terms of probability of bit error, at lower signal levels, except on links where there is an exceptionally large amount of background noise. Under those conditions, not surprisingly, the hold-off time degrades performance.

Development of a Linear Stirling Model with Varying Heat Inputs

NASA Technical Reports Server (NTRS)

Regan, Timothy F.; Lewandowski, Edward J.

2007-01-01

The linear model of the Stirling system developed by NASA Glenn Research Center (GRC) has been extended to include a user-specified heat input. Previously developed linear models were limited to the Stirling convertor and electrical load. They represented the thermodynamic cycle with pressure factors that remained constant. The numerical values of the pressure factors were generated by linearizing GRC s non-linear System Dynamic Model (SDM) of the convertor at a chosen operating point. The pressure factors were fixed for that operating point, thus, the model lost accuracy if a transition to a different operating point were simulated. Although the previous linear model was used in developing controllers that manipulated current, voltage, and piston position, it could not be used in the development of control algorithms that regulated hot-end temperature. This basic model was extended to include the thermal dynamics associated with a hot-end temperature that varies over time in response to external changes as well as to changes in the Stirling cycle. The linear model described herein includes not only dynamics of the piston, displacer, gas, and electrical circuit, but also the transient effects of the heater head thermal inertia. The linear version algebraically couples two separate linear dynamic models, one model of the Stirling convertor and one model of the thermal system, through the pressure factors. The thermal system model includes heat flow of heat transfer fluid, insulation loss, and temperature drops from the heat source to the Stirling convertor expansion space. The linear model was compared to a nonlinear model, and performance was very similar. The resulting linear model can be implemented in a variety of computing environments, and is suitable for analysis with classical and state space controls analysis techniques.

Stochastic hyperfine interactions modeling library-Version 2

NASA Astrophysics Data System (ADS)

Zacate, Matthew O.; Evenson, William E.

2016-02-01

The stochastic hyperfine interactions modeling library (SHIML) provides a set of routines to assist in the development and application of stochastic models of hyperfine interactions. The library provides routines written in the C programming language that (1) read a text description of a model for fluctuating hyperfine fields, (2) set up the Blume matrix, upon which the evolution operator of the system depends, and (3) find the eigenvalues and eigenvectors of the Blume matrix so that theoretical spectra of experimental techniques that measure hyperfine interactions can be calculated. The optimized vector and matrix operations of the BLAS and LAPACK libraries are utilized. The original version of SHIML constructed and solved Blume matrices for methods that measure hyperfine interactions of nuclear probes in a single spin state. Version 2 provides additional support for methods that measure interactions on two different spin states such as Mössbauer spectroscopy and nuclear resonant scattering of synchrotron radiation. Example codes are provided to illustrate the use of SHIML to (1) generate perturbed angular correlation spectra for the special case of polycrystalline samples when anisotropy terms of higher order than A22 can be neglected and (2) generate Mössbauer spectra for polycrystalline samples for pure dipole or pure quadrupole transitions.

The flooding of the San Matías Gulf: The Northern Patagonia sea-level curve

NASA Astrophysics Data System (ADS)

Isla, Federico Ignacio

2013-12-01

Northern Patagonia is characterised by tectonic depressions below present sea level. Some of them are today flooded by the sea; others remain emerged although they are at altitudes of - 50 m (Bajo del Gualicho), - 35 m (Salinas Grandes) and - 7 m (Salina La Piedra). San Matías Gulf also was such an emerged depression below contemporary mean sea level during the Late Pleistocene. It flooded between 11,500 and 11,000 years ago, when the sea level surpassed the sill of the gulf (today 50 m below mean sea level) during postglacial sea-level rise. In those days, shrublands extended on the slopes of the tectonic depression. In-situ pieces of woods dredged from the bottom of the gulf at depths of 70 m gave a conventional age of 11,310 ± 150 years BP. We used the wood, together with dated shells from the continental shelf, and shells and organic matter dated from the San Blas, Negro and Chubut coastal plains to construct a sea-level curve. Sea level rise surpassed the present level somewhat before 6000 years BP, reaching a maximum stand of + 6 m. It has since gently diminished towards present sea level.

Applications for approval to market a new drug; complete response letter; amendments to unapproved applications. Final rule.

PubMed

2008-07-10

The Food and Drug Administration (FDA) is amending its regulations on new drug applications (NDAs) and abbreviated new drug applications (ANDAs) for approval to market new drugs and generic drugs (drugs for which approval is sought in an ANDA). The final rule discontinues FDA's use of approvable letters and not approvable letters when taking action on marketing applications. Instead, we will send applicants a complete response letter to indicate that the review cycle for an application is complete and that the application is not ready for approval. We are also revising the regulations on extending the review cycle due to the submission of an amendment to an unapproved application and starting a new review cycle after the resubmission of an application following receipt of a complete response letter. In addition, we are adding to the regulations on biologics license applications (BLAs) provisions on the issuance of complete response letters to BLA applicants. We are taking these actions to implement the user fee performance goals referenced in the Prescription Drug User Fee Amendments of 2002 (PDUFA III) that address procedures and establish target timeframes for reviewing human drug applications.

The topology of non-linear global carbon dynamics: from tipping points to planetary boundaries

NASA Astrophysics Data System (ADS)

Anderies, J. M.; Carpenter, S. R.; Steffen, Will; Rockström, Johan

2013-12-01

We present a minimal model of land use and carbon cycle dynamics and use it to explore the relationship between non-linear dynamics and planetary boundaries. Only the most basic interactions between land cover and terrestrial, atmospheric, and marine carbon stocks are considered in the model. Our goal is not to predict global carbon dynamics as it occurs in the actual Earth System. Rather, we construct a conceptually reasonable heuristic model of a feedback system between different carbon stocks that captures the qualitative features of the actual Earth System and use it to explore the topology of the boundaries of what can be called a ‘safe operating space’ for humans. The model analysis illustrates the existence of dynamic, non-linear tipping points in carbon cycle dynamics and the potential complexity of planetary boundaries. Finally, we use the model to illustrate some challenges associated with navigating planetary boundaries.

Simplified model to describe the dissociative recombination of linear polyatomic ions of astrophysical interest

NASA Astrophysics Data System (ADS)

Fonseca Dos Santos, Samantha; Douguet, Nicolas; Kokoouline, Viatcheslav; Orel, Ann

2013-05-01

We will present theoretical results on the dissociative recombination (DR) of the linear polyatomic ions HCNH+, HCO+ and N2H+. Besides their astrophysical importance, they also share the characteristic that at low electronic impact energies their DR process happens via the indirect DR mechanism. We apply a general simplified model successfully implemented to treat the DR process of the highly symmetric non-linear molecules H3+, CH3+, H3O+ and NH4+ to calculated cross sections and DR rates for these ions. The model is based on multichannel quantum defect theory and accounts for all the main ingredients of indirect DR. New perspectives on dissociative recombination of HCO+ will also be discussed, including the possible role of HOC+ in storage ring experimental results. This work is supported by the DOE Office of Basic Energy Science and the National Science Foundation, Grant No's PHY-11-60611 and PHY-10-68785.

Experimental and numerical investigation of development of disturbances in the boundary layer on sharp and blunted cone

NASA Astrophysics Data System (ADS)

Borisov, S. P.; Bountin, D. A.; Gromyko, Yu. V.; Khotyanovsky, D. V.; Kudryavtsev, A. N.

2016-10-01

Development of disturbances in the supersonic boundary layer on sharp and blunted cones is studied both experimentally and theoretically. The experiments were conducted at the Transit-M hypersonic wind tunnel of the Institute of Theoretical and Applied Mechanics. Linear stability calculations use the basic flow profiles provided by the numerical simulations performed by solving the Navier-Stokes equations with the ANSYS Fluent and the in-house CFS3D code. Both the global pseudospectral Chebyshev method and the local iteration procedure are employed to solve the eigenvalue problem and determine linear stability characteristics. The calculated amplification factors for disturbances of various frequencies are compared with the experimentally measured pressure fluctuation spectra at different streamwise positions. It is shown that the linear stability calculations predict quite accurately the frequency of the most amplified disturbances and enable us to estimate reasonably well their relative amplitudes.

Pilocarpine disposition and salivary flow responses following intravenous administration to dogs.

PubMed

Weaver, M L; Tanzer, J M; Kramer, P A

1992-08-01

Oral doses of pilocarpine increase salivary flow rates in patients afflicted with xerostomia (dry mouth). This study examined the pharmacokinetics of and a pharmacodynamic response (salivation) to intravenous pilocarpine nitrate administration in dogs. Disposition was linear over a dose range of 225-600 micrograms/kg; plasma concentrations were 10-120 micrograms/L. Elimination was rapid and generally biphasic, with a terminal elimination half-life of approximately 1.3 hr. The systemic clearance of pilocarpine was high (2.22 +/- 0.49 L/kg/hr) and its steady-state volume of distribution (2.30 +/- 0.64 L/kg) was comparable to that of many other basic drugs. All doses of pilocarpine induced measurable submaxillary and parotid salivary flow rates which could be maintained constant over time. Cumulative submaxillary saliva flow was linearly related to total pilocarpine dose. Plasma pilocarpine concentration was linearly related to both steady-state and postinfusion submaxillary salivary flow rates.

Ideal and resistive plasma resistive wall modes and control: linear and nonlinear

NASA Astrophysics Data System (ADS)

Finn, J. M.; Chacon, L.

2004-11-01

Our recent work* on control of linear and nonlinear resistive wall modes (RWM) showed that if there is an ideal plasma mode and a resistive plasma mode, and if the beta limit for the latter is lower (as is typical), then nonlinear resistive wall modes behave basically as nonlinear tearing-like modes locked to the wall. We investigate here the effect of plasma rotation sufficient to stabilize the resistive-plasma RWM but not the ideal plasma RWM. We also review results** showing the effect of normal and poloidal magnetic field sensing, and describe a simple model which is amenable to analytic solution, and which makes previously obtained simulation results transparent. *J. Finn and L. Chacon, 'Control of linear and nonlinear resistive wall modes', Phys. Plas 11, 1866 (2004). **J. Finn, 'Control of resistive wall modes in a cylindrical tokamak with radial and poloidal magnetic field sensors', to appear in Phys. Plasmas, 2004.

Analysis of a Linear System for Variable-Thrust Control in the Terminal Phase of Rendezvous

NASA Technical Reports Server (NTRS)

Hord, Richard A.; Durling, Barbara J.

1961-01-01

A linear system for applying thrust to a ferry vehicle in the 3 terminal phase of rendezvous with a satellite is analyzed. This system requires that the ferry thrust vector per unit mass be variable and equal to a suitable linear combination of the measured position and velocity vectors of the ferry relative to the satellite. The variations of the ferry position, speed, acceleration, and mass ratio are examined for several combinations of the initial conditions and two basic control parameters analogous to the undamped natural frequency and the fraction of critical damping. Upon making a desirable selection of one control parameter and requiring minimum fuel expenditure for given terminal-phase initial conditions, a simplified analysis in one dimension practically fixes the choice of the remaining control parameter. The system can be implemented by an automatic controller or by a pilot.

Theoretical studies of solar oscillations

NASA Technical Reports Server (NTRS)

Goldreich, P.

1980-01-01

Possible sources for the excitation of the solar 5 minute oscillations were investigated and a linear non-adiabatic stability code was applied to a preliminary study of the solar g-modes with periods near 160 minutes. Although no definitive conclusions concerning the excitation of these modes were reached, the excitation of the 5 minute oscillations by turbulent stresses in the convection zone remains a viable possibility. Theoretical calculations do not offer much support for the identification of the 160 minute global solar oscillation (reported by several independent observers) as a solar g-mode. A significant advance was made in attempting to reconcile mixing-length theory with the results of the calculations of linearly unstable normal modes. Calculations show that in a convective envelope prepared according to mixing length theory, the only linearly unstable modes are those which correspond to the turbulent eddies which are the basic element of the heuristic mixing length theory.

Establishing the minimal number of virtual reality simulator training sessions necessary to develop basic laparoscopic skills competence: evaluation of the learning curve.

PubMed

Duarte, Ricardo Jordão; Cury, José; Oliveira, Luis Carlos Neves; Srougi, Miguel

2013-01-01

Medical literature is scarce on information to define a basic skills training program for laparoscopic surgery (peg and transferring, cutting, clipping). The aim of this study was to determine the minimal number of simulator sessions of basic laparoscopic tasks necessary to elaborate an optimal virtual reality training curriculum. Eleven medical students with no previous laparoscopic experience were spontaneously enrolled. They were submitted to simulator training sessions starting at level 1 (Immersion Lap VR, San Jose, CA), including sequentially camera handling, peg and transfer, clipping and cutting. Each student trained twice a week until 10 sessions were completed. The score indexes were registered and analyzed. The total of errors of the evaluation sequences (camera, peg and transfer, clipping and cutting) were computed and thereafter, they were correlated to the total of items evaluated in each step, resulting in a success percent ratio for each student for each set of each completed session. Thereafter, we computed the cumulative success rate in 10 sessions, obtaining an analysis of the learning process. By non-linear regression the learning curve was analyzed. By the non-linear regression method the learning curve was analyzed and a r2 = 0.73 (p < 0.001) was obtained, being necessary 4.26 (∼five sessions) to reach the plateau of 80% of the estimated acquired knowledge, being that 100% of the students have reached this level of skills. From the fifth session till the 10th, the gain of knowledge was not significant, although some students reached 96% of the expected improvement. This study revealed that after five simulator training sequential sessions the students' learning curve reaches a plateau. The forward sessions in the same difficult level do not promote any improvement in laparoscopic basic surgical skills, and the students should be introduced to a more difficult training tasks level.

Impulse measurement using an Arduíno

NASA Astrophysics Data System (ADS)

Espindola, P. R.; Cena, C. R.; Alves, D. C. B.; Bozano, D. F.; Goncalves, A. M. B.

2018-05-01

In this paper, we propose a simple experimental apparatus that can measure the force variation over time to study the impulse-momentum theorem. In this proposal, a body attached to a rubber string falls freely from rest until it stretches and changes the linear momentum. During that process the force due to the tension on the rubber string is measured with a load cell by using an Arduíno board. We check the instrumental results with the basic concept of impulse, finding the area under the force versus time curve and comparing this with the linear momentum variation estimated from software analysis. The apparatus is presented as a simple and low cost alternative to mechanical physics laboratories.

Analysis of continuously rotating quadrupole focusing channels using generalized Courant-Snyder theory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chung, Moses; Qin, Hong; Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026

2013-08-15

By extending the recently developed generalized Courant-Snyder theory for coupled transverse beam dynamics, we have constructed the Gaussian beam distribution and its projections with arbitrary mode emittance ratios. The new formulation has been applied to a continuously rotating quadrupole focusing channel because the basic properties of this channel are known theoretically and could also be investigated experimentally in a compact setup such as the linear Paul trap configuration. The new formulation retains a remarkably similar mathematical structure to the original Courant-Snyder theory, and thus, provides a powerful theoretical tool to investigate coupled transverse beam dynamics in general and more complexmore » linear focusing channels.« less

Linear system identification via backward-time observer models

NASA Technical Reports Server (NTRS)

Juang, Jer-Nan; Phan, Minh

1993-01-01

This paper presents an algorithm to identify a state-space model of a linear system using a backward-time approach. The procedure consists of three basic steps. First, the Markov parameters of a backward-time observer are computed from experimental input-output data. Second, the backward-time observer Markov parameters are decomposed to obtain the backward-time system Markov parameters (backward-time pulse response samples) from which a backward-time state-space model is realized using the Eigensystem Realization Algorithm. Third, the obtained backward-time state space model is converted to the usual forward-time representation. Stochastic properties of this approach will be discussed. Experimental results are given to illustrate when and to what extent this concept works.

The general linear inverse problem - Implication of surface waves and free oscillations for earth structure.

NASA Technical Reports Server (NTRS)

Wiggins, R. A.

1972-01-01

The discrete general linear inverse problem reduces to a set of m equations in n unknowns. There is generally no unique solution, but we can find k linear combinations of parameters for which restraints are determined. The parameter combinations are given by the eigenvectors of the coefficient matrix. The number k is determined by the ratio of the standard deviations of the observations to the allowable standard deviations in the resulting solution. Various linear combinations of the eigenvectors can be used to determine parameter resolution and information distribution among the observations. Thus we can determine where information comes from among the observations and exactly how it constraints the set of possible models. The application of such analyses to surface-wave and free-oscillation observations indicates that (1) phase, group, and amplitude observations for any particular mode provide basically the same type of information about the model; (2) observations of overtones can enhance the resolution considerably; and (3) the degree of resolution has generally been overestimated for many model determinations made from surface waves.

Classical Michaelis-Menten and system theory approach to modeling metabolite formation kinetics.

PubMed

Popović, Jovan

2004-01-01

When single doses of drug are administered and kinetics are linear, techniques, which are based on the compartment approach and the linear system theory approach, in modeling the formation of the metabolite from the parent drug are proposed. Unlike the purpose-specific compartment approach, the methodical, conceptual and computational uniformity in modeling various linear biomedical systems is the dominant characteristic of the linear system approach technology. Saturation of the metabolic reaction results in nonlinear kinetics according to the Michaelis-Menten equation. The two compartment open model with Michaelis-Menten elimination kinetics is theorethicaly basic when single doses of drug are administered. To simulate data or to fit real data using this model, one must resort to numerical integration. A biomathematical model for multiple dosage regimen calculations of nonlinear metabolic systems in steady-state and a working example with phenytoin are presented. High correlation between phenytoin steady-state serum levels calculated from individual Km and Vmax values in the 15 adult epileptic outpatients and the observed levels at the third adjustment of phenytoin daily dose (r=0.961, p<0.01) were found.

A dose-response curve for biodosimetry from a 6 MV electron linear accelerator

PubMed Central

Lemos-Pinto, M.M.P.; Cadena, M.; Santos, N.; Fernandes, T.S.; Borges, E.; Amaral, A.

2015-01-01

Biological dosimetry (biodosimetry) is based on the investigation of radiation-induced biological effects (biomarkers), mainly dicentric chromosomes, in order to correlate them with radiation dose. To interpret the dicentric score in terms of absorbed dose, a calibration curve is needed. Each curve should be constructed with respect to basic physical parameters, such as the type of ionizing radiation characterized by low or high linear energy transfer (LET) and dose rate. This study was designed to obtain dose calibration curves by scoring of dicentric chromosomes in peripheral blood lymphocytes irradiated in vitro with a 6 MV electron linear accelerator (Mevatron M, Siemens, USA). Two software programs, CABAS (Chromosomal Aberration Calculation Software) and Dose Estimate, were used to generate the curve. The two software programs are discussed; the results obtained were compared with each other and with other published low LET radiation curves. Both software programs resulted in identical linear and quadratic terms for the curve presented here, which was in good agreement with published curves for similar radiation quality and dose rates. PMID:26445334

How could multimedia information about dental implant surgery effects patients' anxiety level?

PubMed

Kazancioglu, H-O; Dahhan, A-S; Acar, A-H

2017-01-01

To evaluate the effects of different patient education techniques on patients' anxiety levels before and after dental implant surgery. Sixty patients were randomized into three groups; each contained 20 patients; [group 1, basic information given verbally, with details of operation and recovery; group 2 (study group), basic information given verbally with details of operative procedures and recovery, and by watching a movie on single implant surgery]; and a control group [basic information given verbally "but it was devoid of the details of the operative procedures and recovery"]. Anxiety levels were assessed using the Spielberger's State-Trait Anxiety Inventory (STAI) and Modified Dental Anxiety Scale (MDAS). Pain was assessed with a visual analog scale (VAS). The most significant changes were observed in the movie group (P < 0.05). Patients who were more anxious also used more analgesic medication. Linear regression analysis showed that female patients had higher levels of anxiety (P < 0.05). Preoperative multimedia information increases anxiety level.

Currency arbitrage detection using a binary integer programming model

NASA Astrophysics Data System (ADS)

Soon, Wanmei; Ye, Heng-Qing

2011-04-01

In this article, we examine the use of a new binary integer programming (BIP) model to detect arbitrage opportunities in currency exchanges. This model showcases an excellent application of mathematics to the real world. The concepts involved are easily accessible to undergraduate students with basic knowledge in Operations Research. Through this work, students can learn to link several types of basic optimization models, namely linear programming, integer programming and network models, and apply the well-known sensitivity analysis procedure to accommodate realistic changes in the exchange rates. Beginning with a BIP model, we discuss how it can be reduced to an equivalent but considerably simpler model, where an efficient algorithm can be applied to find the arbitrages and incorporate the sensitivity analysis procedure. A simple comparison is then made with a different arbitrage detection model. This exercise helps students learn to apply basic Operations Research concepts to a practical real-life example, and provides insights into the processes involved in Operations Research model formulations.

The Elementary Operations of Human Vision Are Not Reducible to Template-Matching

PubMed Central

Neri, Peter

2015-01-01

It is generally acknowledged that biological vision presents nonlinear characteristics, yet linear filtering accounts of visual processing are ubiquitous. The template-matching operation implemented by the linear-nonlinear cascade (linear filter followed by static nonlinearity) is the most widely adopted computational tool in systems neuroscience. This simple model achieves remarkable explanatory power while retaining analytical tractability, potentially extending its reach to a wide range of systems and levels in sensory processing. The extent of its applicability to human behaviour, however, remains unclear. Because sensory stimuli possess multiple attributes (e.g. position, orientation, size), the issue of applicability may be asked by considering each attribute one at a time in relation to a family of linear-nonlinear models, or by considering all attributes collectively in relation to a specified implementation of the linear-nonlinear cascade. We demonstrate that human visual processing can operate under conditions that are indistinguishable from linear-nonlinear transduction with respect to substantially different stimulus attributes of a uniquely specified target signal with associated behavioural task. However, no specific implementation of a linear-nonlinear cascade is able to account for the entire collection of results across attributes; a satisfactory account at this level requires the introduction of a small gain-control circuit, resulting in a model that no longer belongs to the linear-nonlinear family. Our results inform and constrain efforts at obtaining and interpreting comprehensive characterizations of the human sensory process by demonstrating its inescapably nonlinear nature, even under conditions that have been painstakingly fine-tuned to facilitate template-matching behaviour and to produce results that, at some level of inspection, do conform to linear filtering predictions. They also suggest that compliance with linear transduction may be the targeted outcome of carefully crafted nonlinear circuits, rather than default behaviour exhibited by basic components. PMID:26556758

Development of a Linear Stirling System Model with Varying Heat Inputs

NASA Technical Reports Server (NTRS)

Regan, Timothy F.; Lewandowski, Edward J.

2007-01-01

The linear model of the Stirling system developed by NASA Glenn Research Center (GRC) has been extended to include a user-specified heat input. Previously developed linear models were limited to the Stirling convertor and electrical load. They represented the thermodynamic cycle with pressure factors that remained constant. The numerical values of the pressure factors were generated by linearizing GRC's nonlinear System Dynamic Model (SDM) of the convertor at a chosen operating point. The pressure factors were fixed for that operating point, thus, the model lost accuracy if a transition to a different operating point were simulated. Although the previous linear model was used in developing controllers that manipulated current, voltage, and piston position, it could not be used in the development of control algorithms that regulated hot-end temperature. This basic model was extended to include the thermal dynamics associated with a hot-end temperature that varies over time in response to external changes as well as to changes in the Stirling cycle. The linear model described herein includes not only dynamics of the piston, displacer, gas, and electrical circuit, but also the transient effects of the heater head thermal inertia. The linear version algebraically couples two separate linear dynamic models, one model of the Stirling convertor and one model of the thermal system, through the pressure factors. The thermal system model includes heat flow of heat transfer fluid, insulation loss, and temperature drops from the heat source to the Stirling convertor expansion space. The linear model was compared to a nonlinear model, and performance was very similar. The resulting linear model can be implemented in a variety of computing environments, and is suitable for analysis with classical and state space controls analysis techniques.

An accurate density functional theory for the vapor-liquid interface of associating chain molecules based on the statistical associating fluid theory for potentials of variable range

NASA Astrophysics Data System (ADS)

Gloor, Guy J.; Jackson, George; Blas, Felipe J.; del Río, Elvira Martín; de Miguel, Enrique

2004-12-01

A Helmholtz free energy density functional is developed to describe the vapor-liquid interface of associating chain molecules. The functional is based on the statistical associating fluid theory with attractive potentials of variable range (SAFT-VR) for the homogenous fluid [A. Gil-Villegas, A. Galindo, P. J. Whitehead, S. J. Mills, G. Jackson, and A. N. Burgess, J. Chem. Phys. 106, 4168 (1997)]. A standard perturbative density functional theory (DFT) is constructed by partitioning the free energy density into a reference term (which incorporates all of the short-range interactions, and is treated locally) and an attractive perturbation (which incorporates the long-range dispersion interactions). In our previous work [F. J. Blas, E. Martín del Río, E. de Miguel, and G. Jackson, Mol. Phys. 99, 1851 (2001); G. J. Gloor, F. J. Blas, E. Martín del Río, E. de Miguel, and G. Jackson, Fluid Phase Equil. 194, 521 (2002)] we used a mean-field version of the theory (SAFT-HS) in which the pair correlations were neglected in the attractive term. This provides only a qualitative description of the vapor-liquid interface, due to the inadequate mean-field treatment of the vapor-liquid equilibria. Two different approaches are used to include the correlations in the attractive term: in the first, the free energy of the homogeneous fluid is partitioned such that the effect of correlations are incorporated in the local reference term; in the second, a density averaged correlation function is incorporated into the perturbative term in a similar way to that proposed by Toxvaerd [S. Toxvaerd, J. Chem. Phys. 64, 2863 (1976)]. The latter is found to provide the most accurate description of the vapor-liquid surface tension on comparison with new simulation data for a square-well fluid of variable range. The SAFT-VR DFT is used to examine the effect of molecular chain length and association on the surface tension. Different association schemes (dimerization, straight and branched chain formation, and network structures) are examined separately. The surface tension of the associating fluid is found to be bounded between the nonassociating and fully associated limits (both of which correspond to equivalent nonassociating systems). The temperature dependence of the surface tension is found to depend strongly on the balance between the strength and range of the association, and on the particular association scheme. In the case of a system with a strong but very localized association interaction, the surface tension exhibits the characteristic "s shaped" behavior with temperature observed in fluids such as water and alkanols. The various types of curves observed in real substances can be reproduced by the theory. It is very gratifying that a DFT based on SAFT-VR free energy can provide an accurate quantitative description of the surface tension of both the model and experimental systems.

JADAMILU: a software code for computing selected eigenvalues of large sparse symmetric matrices

NASA Astrophysics Data System (ADS)

Bollhöfer, Matthias; Notay, Yvan

2007-12-01

A new software code for computing selected eigenvalues and associated eigenvectors of a real symmetric matrix is described. The eigenvalues are either the smallest or those closest to some specified target, which may be in the interior of the spectrum. The underlying algorithm combines the Jacobi-Davidson method with efficient multilevel incomplete LU (ILU) preconditioning. Key features are modest memory requirements and robust convergence to accurate solutions. Parameters needed for incomplete LU preconditioning are automatically computed and may be updated at run time depending on the convergence pattern. The software is easy to use by non-experts and its top level routines are written in FORTRAN 77. Its potentialities are demonstrated on a few applications taken from computational physics. Program summaryProgram title: JADAMILU Catalogue identifier: ADZT_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADZT_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 101 359 No. of bytes in distributed program, including test data, etc.: 7 493 144 Distribution format: tar.gz Programming language: Fortran 77 Computer: Intel or AMD with g77 and pgf; Intel EM64T or Itanium with ifort; AMD Opteron with g77, pgf and ifort; Power (IBM) with xlf90. Operating system: Linux, AIX RAM: problem dependent Word size: real:8; integer: 4 or 8, according to user's choice Classification: 4.8 Nature of problem: Any physical problem requiring the computation of a few eigenvalues of a symmetric matrix. Solution method: Jacobi-Davidson combined with multilevel ILU preconditioning. Additional comments: We supply binaries rather than source code because JADAMILU uses the following external packages: MC64. This software is copyrighted software and not freely available. COPYRIGHT (c) 1999 Council for the Central Laboratory of the Research Councils. AMD. Copyright (c) 2004-2006 by Timothy A. Davis, Patrick R. Amestoy, and Iain S. Duff. Source code is distributed by the authors under the GNU LGPL licence. BLAS. The reference BLAS is a freely-available software package. It is available from netlib via anonymous ftp and the World Wide Web. LAPACK. The complete LAPACK package or individual routines from LAPACK are freely available on netlib and can be obtained via the World Wide Web or anonymous ftp. For maximal benefit to the community, we added the sources we are proprietary of to the tar.gz file submitted for inclusion in the CPC library. However, as explained in the README file, users willing to compile the code instead of using binaries should first obtain the sources for the external packages mentioned above (email and/or web addresses are provided). Running time: Problem dependent; the test examples provided with the code only take a few seconds to run; timing results for large scale problems are given in Section 5.

Theory of Financial Risk and Derivative Pricing

NASA Astrophysics Data System (ADS)

Bouchaud, Jean-Philippe; Potters, Marc

2009-01-01

Foreword; Preface; 1. Probability theory: basic notions; 2. Maximum and addition of random variables; 3. Continuous time limit, Ito calculus and path integrals; 4. Analysis of empirical data; 5. Financial products and financial markets; 6. Statistics of real prices: basic results; 7. Non-linear correlations and volatility fluctuations; 8. Skewness and price-volatility correlations; 9. Cross-correlations; 10. Risk measures; 11. Extreme correlations and variety; 12. Optimal portfolios; 13. Futures and options: fundamental concepts; 14. Options: hedging and residual risk; 15. Options: the role of drift and correlations; 16. Options: the Black and Scholes model; 17. Options: some more specific problems; 18. Options: minimum variance Monte-Carlo; 19. The yield curve; 20. Simple mechanisms for anomalous price statistics; Index of most important symbols; Index.

Theory of Financial Risk and Derivative Pricing - 2nd Edition

NASA Astrophysics Data System (ADS)

Bouchaud, Jean-Philippe; Potters, Marc

2003-12-01

Foreword; Preface; 1. Probability theory: basic notions; 2. Maximum and addition of random variables; 3. Continuous time limit, Ito calculus and path integrals; 4. Analysis of empirical data; 5. Financial products and financial markets; 6. Statistics of real prices: basic results; 7. Non-linear correlations and volatility fluctuations; 8. Skewness and price-volatility correlations; 9. Cross-correlations; 10. Risk measures; 11. Extreme correlations and variety; 12. Optimal portfolios; 13. Futures and options: fundamental concepts; 14. Options: hedging and residual risk; 15. Options: the role of drift and correlations; 16. Options: the Black and Scholes model; 17. Options: some more specific problems; 18. Options: minimum variance Monte-Carlo; 19. The yield curve; 20. Simple mechanisms for anomalous price statistics; Index of most important symbols; Index.

Effectiveness of basic display augmentation in vehicular control by visual field cues

NASA Technical Reports Server (NTRS)

Grunwald, A. J.; Merhav, S. J.

1978-01-01

The paper investigates the effectiveness of different basic display augmentation concepts - fixed reticle, velocity vector, and predicted future vehicle path - for RPVs controlled by a vehicle-mounted TV camera. The task is lateral manual control of a low flying RPV along a straight reference line in the presence of random side gusts. The man-machine system and the visual interface are modeled as a linear time-invariant system. Minimization of a quadratic performance criterion is assumed to underlie the control strategy of a well-trained human operator. The solution for the optimal feedback matrix enables the explicit computation of the variances of lateral deviation and directional error of the vehicle and of the control force that are used as performance measures.

Towards enhancing and delaying disturbances in free shear flows

NASA Technical Reports Server (NTRS)

Criminale, W. O.; Jackson, T. L.; Lasseigne, D. G.

1994-01-01

The family of shear flows comprising the jet, wake, and the mixing layer are subjected to perturbations in an inviscid incompressible fluid. By modeling the basic mean flows as parallel with piecewise linear variations for the velocities, complete and general solutions to the linearized equations of motion can be obtained in closed form as functions of all space variables and time when posed as an initial value problem. The results show that there is a continuous as well as the discrete spectrum that is more familiar in stability theory and therefore there can be both algebraic and exponential growth of disturbances in time. These bases make it feasible to consider control of such flows. To this end, the possibility of enhancing the disturbances in the mixing layer and delaying the onset in the jet and wake is investigated. It is found that growth of perturbations can be delayed to a considerable degree for the jet and the wake but, by comparison, cannot be enhanced in the mixing layer. By using moving coordinates, a method for demonstrating the predominant early and long time behavior of disturbances in these flows is given for continuous velocity profiles. It is shown that the early time transients are always algebraic whereas the asymptotic limit is that of an exponential normal mode. Numerical treatment of the new governing equations confirm the conclusions reached by use of the piecewise linear basic models. Although not pursued here, feedback mechanisms designed for control of the flow could be devised using the results of this work.

Optimal estimation and scheduling in aquifer management using the rapid feedback control method

NASA Astrophysics Data System (ADS)

Ghorbanidehno, Hojat; Kokkinaki, Amalia; Kitanidis, Peter K.; Darve, Eric

2017-12-01

Management of water resources systems often involves a large number of parameters, as in the case of large, spatially heterogeneous aquifers, and a large number of "noisy" observations, as in the case of pressure observation in wells. Optimizing the operation of such systems requires both searching among many possible solutions and utilizing new information as it becomes available. However, the computational cost of this task increases rapidly with the size of the problem to the extent that textbook optimization methods are practically impossible to apply. In this paper, we present a new computationally efficient technique as a practical alternative for optimally operating large-scale dynamical systems. The proposed method, which we term Rapid Feedback Controller (RFC), provides a practical approach for combined monitoring, parameter estimation, uncertainty quantification, and optimal control for linear and nonlinear systems with a quadratic cost function. For illustration, we consider the case of a weakly nonlinear uncertain dynamical system with a quadratic objective function, specifically a two-dimensional heterogeneous aquifer management problem. To validate our method, we compare our results with the linear quadratic Gaussian (LQG) method, which is the basic approach for feedback control. We show that the computational cost of the RFC scales only linearly with the number of unknowns, a great improvement compared to the basic LQG control with a computational cost that scales quadratically. We demonstrate that the RFC method can obtain the optimal control values at a greatly reduced computational cost compared to the conventional LQG algorithm with small and controllable losses in the accuracy of the state and parameter estimation.

Environmental Health Monitor: Advanced Development of Temperature Sensor Suite.

DTIC Science & Technology

1995-07-30

systems was implemented using program code existing at Veritay. The software , written in Microsoft® QuickBASIC, facilitated program changes for...currently unforeseen reason re-calibration is needed, this can be readily * accommodated by a straightforward change in the software program---without...unit. A linear relationship between these differences * was obtained using curve fitting software . The ½/-inch globe to 6-inch globe correlation * was

USSR Report, Electronics and Electrical Engineering, No. 104

DTIC Science & Technology

1983-06-13

shaping of silicon crystals during their growth is a modification of inductive contactless forming of rods and tubes directly from the melt on a...MANUFACTURING TECHNOLOGY Induction Systems for Electromagnetic Shaping of Silicon Crystal During.Growth (L. R. Lev; ELEKTROTEKHNIKA, Feb 83) • • • x...et al.; IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY: ELEKTROMEKHANIKA, Dec 82) 18 Basic Design of Linear- Induction Traction Motors for High-Speed

The fundamentals of adaptive grid movement

NASA Technical Reports Server (NTRS)

Eiseman, Peter R.

1990-01-01

Basic grid point movement schemes are studied. The schemes are referred to as adaptive grids. Weight functions and equidistribution in one dimension are treated. The specification of coefficients in the linear weight, attraction to a given grid or a curve, and evolutionary forces are considered. Curve by curve and finite volume methods are described. The temporal coupling of partial differential equations solvers and grid generators was discussed.

Coincidence degree and periodic solutions of neutral equations

NASA Technical Reports Server (NTRS)

Hale, J. K.; Mawhin, J.

1973-01-01

The problem of existence of periodic solutions for some nonautonomous neutral functional differential equations is examined. It is an application of a basic theorem on the Fredholm alternative for periodic solutions of some linear neutral equations and of a generalized Leray-Schauder theory. Although proofs are simple, the results are nontrivial extensions to the neutral case of existence theorems for periodic solutions of functional differential equations.

Multiscale Simulations of Barrier and Aging Properties of Polymer Nanocomposites

DTIC Science & Technology

2013-10-29

Complexation Between Weakly Basic Dendrimers and Linear Polyelectrolytes: Effects of Chain Stiffness, Grafts, and pOH,” Thomas Lewis, Gunja Pandav, Ahmad Omar...November 2012. (c) Presentations 20.0010/29/2013 Venkat Ganesan, Thomas Lewis. Interactions between Grafted Cationic Dendrimers and Anionic Bilayer... dendrimers have shown great promise in drug and gene therapy applications. Despite the advantages realized through positively charged dendrimers , a

Atomic Schroedinger cat-like states

DOE Office of Scientific and Technical Information (OSTI.GOV)

Enriquez-Flores, Marco; Rosas-Ortiz, Oscar; Departamento de Fisica, Cinvestav, A.P. 14-740, Mexico D.F. 07000

2010-10-11

After a short overview of the basic mathematical structure of quantum mechanics we analyze the Schroedinger's antinomic example of a living and dead cat mixed in equal parts. Superpositions of Glauber kets are shown to approximate such macroscopic states. Then, two-level atomic states are used to construct mesoscopic kittens as appropriate linear combinations of angular momentum eigenkets for j = 1/2. Some general comments close the present contribution.

Introduction to Adjoint Models

NASA Technical Reports Server (NTRS)

Errico, Ronald M.

2015-01-01

In this lecture, some fundamentals of adjoint models will be described. This includes a basic derivation of tangent linear and corresponding adjoint models from a parent nonlinear model, the interpretation of adjoint-derived sensitivity fields, a description of methods of automatic differentiation, and the use of adjoint models to solve various optimization problems, including singular vectors. Concluding remarks will attempt to correct common misconceptions about adjoint models and their utilization.

The microcomputer scientific software series 3: general linear model--analysis of variance.

Treesearch

Harold M. Rauscher

1985-01-01

A BASIC language set of programs, designed for use on microcomputers, is presented. This set of programs will perform the analysis of variance for any statistical model describing either balanced or unbalanced designs. The program computes and displays the degrees of freedom, Type I sum of squares, and the mean square for the overall model, the error, and each factor...

Solvatochromism and linear solvation energy relationship of the kinase inhibitor SKF86002

NASA Astrophysics Data System (ADS)

Khattab, Muhammad; Van Dongen, Madeline; Wang, Feng; Clayton, Andrew H. A.

2017-01-01

We studied the spectroscopic characteristics of SKF86002, an anti-inflammatory and tyrosine kinase inhibitor drug candidate. Two conformers SKF86002A and SKF86002B are separated by energy barriers of 19.68 kJ·mol- 1 and 6.65 kJ·mol- 1 due to H-bonds, and produce the three major UV-Vis absorption bands at 325 nm, 260 nm and 210 nm in cyclohexane solutions. This environment-sensitive fluorophore exhibited emission in the 400-500 nm range with a marked response to changes in environment polarity. By using twenty-two solvents for the solvatochromism study, it was noticed that solvent polarity, represented by dielectric constant, was well correlated with the emission wavelength maxima of SKF86002. Thus, the SKF86002 fluorescence peak red shifted in aprotic solvents from 397.5 nm in cyclohexane to 436 nm in DMSO. While the emission maximum in hydrogen donating solvents ranged from 420 nm in t-butanol to 446 nm in N-methylformamide. Employing Lippert-Mataga, Bakhshiev and Kawski models, we found that one linear correlation provided a satisfactory description of polarity effect of 18 solvents on the spectral changes of SKF86002 with R2 values 0.78, 0.80 and 0.80, respectively. Additionally, the multicomponent linear regression analysis of Kamlet-Taft (R2 = 0.94) revealed that solvent acidity, basicity and polarity accounted for 31%, 24% and 45% of solvent effects on SKF86002 emission, respectively. While Catalán correlation (R2 = 0.92) revealed that solvatochromic change of SKF86002 emission was attributed to changes in solvent dipolarity (71%), solvent polarity (12%), solvent acidity (11%) and solvent basicity (6%). Plot of Reichardt transition energies and emission energies of SKF86002 in 18 solvents showed also a linear correlation with R2 = 0.90. The dipole moment difference between excited and ground state was calculated to be 3.4-3.5 debye.

Solvatochromism and linear solvation energy relationship of the kinase inhibitor SKF86002.

PubMed

Khattab, Muhammad; Van Dongen, Madeline; Wang, Feng; Clayton, Andrew H A

2017-01-05

We studied the spectroscopic characteristics of SKF86002, an anti-inflammatory and tyrosine kinase inhibitor drug candidate. Two conformers SKF86002A and SKF86002B are separated by energy barriers of 19.68kJ·mol(-1) and 6.65kJ·mol(-1) due to H-bonds, and produce the three major UV-Vis absorption bands at 325nm, 260nm and 210nm in cyclohexane solutions. This environment-sensitive fluorophore exhibited emission in the 400-500nm range with a marked response to changes in environment polarity. By using twenty-two solvents for the solvatochromism study, it was noticed that solvent polarity, represented by dielectric constant, was well correlated with the emission wavelength maxima of SKF86002. Thus, the SKF86002 fluorescence peak red shifted in aprotic solvents from 397.5nm in cyclohexane to 436nm in DMSO. While the emission maximum in hydrogen donating solvents ranged from 420nm in t-butanol to 446nm in N-methylformamide. Employing Lippert-Mataga, Bakhshiev and Kawski models, we found that one linear correlation provided a satisfactory description of polarity effect of 18 solvents on the spectral changes of SKF86002 with R(2) values 0.78, 0.80 and 0.80, respectively. Additionally, the multicomponent linear regression analysis of Kamlet-Taft (R(2)=0.94) revealed that solvent acidity, basicity and polarity accounted for 31%, 24% and 45% of solvent effects on SKF86002 emission, respectively. While Catalán correlation (R(2)=0.92) revealed that solvatochromic change of SKF86002 emission was attributed to changes in solvent dipolarity (71%), solvent polarity (12%), solvent acidity (11%) and solvent basicity (6%). Plot of Reichardt transition energies and emission energies of SKF86002 in 18 solvents showed also a linear correlation with R(2)=0.90. The dipole moment difference between excited and ground state was calculated to be 3.4-3.5debye. Copyright © 2016 Elsevier B.V. All rights reserved.

Comparison of buried sand ridges and regressive sand ridges on the outer shelf of the East China Sea

NASA Astrophysics Data System (ADS)

Wu, Ziyin; Jin, Xianglong; Zhou, Jieqiong; Zhao, Dineng; Shang, Jihong; Li, Shoujun; Cao, Zhenyi; Liang, Yuyang

2017-06-01

Based on multi-beam echo soundings and high-resolution single-channel seismic profiles, linear sand ridges in U14 and U2 on the East China Sea (ECS) shelf are identified and compared in detail. Linear sand ridges in U14 are buried sand ridges, which are 90 m below the seafloor. It is presumed that these buried sand ridges belong to the transgressive systems tract (TST) formed 320-200 ka ago and that their top interface is the maximal flooding surface (MFS). Linear sand ridges in U2 are regressive sand ridges. It is presumed that these buried sand ridges belong to the TST of the last glacial maximum (LGM) and that their top interface is the MFS of the LGM. Four sub-stage sand ridges of U2 are discerned from the high-resolution single-channel seismic profile and four strikes of regressive sand ridges are distinguished from the submarine topographic map based on the multi-beam echo soundings. These multi-stage and multi-strike linear sand ridges are the response of, and evidence for, the evolution of submarine topography with respect to sea-level fluctuations since the LGM. Although the difference in the age of formation between U14 and U2 is 200 ka and their sequences are 90 m apart, the general strikes of the sand ridges are similar. This indicates that the basic configuration of tidal waves on the ECS shelf has been stable for the last 200 ka. A basic evolutionary model of the strata of the ECS shelf is proposed, in which sea-level change is the controlling factor. During the sea-level change of about 100 ka, five to six strata are developed and the sand ridges develop in the TST. A similar story of the evolution of paleo-topography on the ECS shelf has been repeated during the last 300 ka.

A finite difference Hartree-Fock program for atoms and diatomic molecules

NASA Astrophysics Data System (ADS)

Kobus, Jacek

2013-03-01

The newest version of the two-dimensional finite difference Hartree-Fock program for atoms and diatomic molecules is presented. This is an updated and extended version of the program published in this journal in 1996. It can be used to obtain reference, Hartree-Fock limit values of total energies and multipole moments for a wide range of diatomic molecules and their ions in order to calibrate existing and develop new basis sets, calculate (hyper)polarizabilities (αzz, βzzz, γzzzz, Az,zz, Bzz,zz) of atoms, homonuclear and heteronuclear diatomic molecules and their ions via the finite field method, perform DFT-type calculations using LDA or B88 exchange functionals and LYP or VWN correlations ones or the self-consistent multiplicative constant method, perform one-particle calculations with (smooth) Coulomb and Krammers-Henneberger potentials and take account of finite nucleus models. The program is easy to install and compile (tarball+configure+make) and can be used to perform calculations within double- or quadruple-precision arithmetic. Catalogue identifier: ADEB_v2_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADEB_v2_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GNU General Public License version 2 No. of lines in distributed program, including test data, etc.: 171196 No. of bytes in distributed program, including test data, etc.: 9481802 Distribution format: tar.gz Programming language: Fortran 77, C. Computer: any 32- or 64-bit platform. Operating system: Unix/Linux. RAM: Case dependent, from few MB to many GB Classification: 16.1. Catalogue identifier of previous version: ADEB_v1_0 Journal reference of previous version: Comput. Phys. Comm. 98(1996)346 Does the new version supersede the previous version?: Yes Nature of problem: The program finds virtually exact solutions of the Hartree-Fock and density functional theory type equations for atoms, diatomic molecules and their ions. The lowest energy eigenstates of a given irreducible representation and spin can be obtained. The program can be used to perform one-particle calculations with (smooth) Coulomb and Krammers-Henneberger potentials and also DFT-type calculations using LDA or B88 exchange functionals and LYP or VWN correlations ones or the self-consistent multiplicative constant method. Solution method: Single-particle two-dimensional numerical functions (orbitals) are used to construct an antisymmetric many-electron wave function of the restricted open-shell Hartree-Fock model. The orbitals are obtained by solving the Hartree-Fock equations as coupled two-dimensional second-order (elliptic) partial differential equations (PDEs). The Coulomb and exchange potentials are obtained as solutions of the corresponding Poisson equations. The PDEs are discretized by the eighth-order central difference stencil on a two-dimensional single grid, and the resulting large and sparse system of linear equations is solved by the (multicolour) successive overrelaxation ((MC)SOR) method. The self-consistent-field iterations are interwoven with the (MC)SOR ones and orbital energies and normalization factors are used to monitor the convergence. The accuracy of solutions depends mainly on the grid and the system under consideration, which means that within double precision arithmetic one can obtain orbitals and energies having up to 12 significant figures. If more accurate results are needed, quadruple-precision floating-point arithmetic can be used. Reasons for new version: Additional features, many modifications and corrections, improved convergence rate, overhauled code and documentation. Summary of revisions: see ChangeLog found in tar.gz archive Restrictions: The present version of the program is restricted to 60 orbitals. The maximum grid size is determined at compilation time. Unusual features: The program uses two C routines for allocating and deallocating memory. Several BLAS (Basic Linear Algebra System) routines are emulated by the program. When possible they should be replaced by their library equivalents. Additional comments: automake and autoconf tools are required to build and compile the program; checked with f77, gfortran and ifort compilers Running time: Very case dependent - from a few CPU seconds for the H2 defined on a small grid up to several weeks for the Hartree-Fock-limit calculations for 40-50 electron molecules.

A simple and rapid chromatographic method to determine unauthorized basic colorants (rhodamine B, auramine O, and pararosaniline) in processed foods.

PubMed

Tatebe, Chiye; Zhong, Xining; Ohtsuki, Takashi; Kubota, Hiroki; Sato, Kyoko; Akiyama, Hiroshi

2014-09-01

A simple and rapid high-performance liquid chromatography (HPLC) method to determine basic colorants such as pararosaniline (PA), auramine O (AO), and rhodamine B (RB) in various processed foods was developed. Linearity of the calibration curves ranged from 0.05 to 50 μg/mL for PA and 0.05-100 μg/mL for AO and RB. The detection and quantification limits (LOD and LOQ) of the basic colorants, which were evaluated as signal-to-noise ratios of 3 for LOD and 10 for LOQ, ranged from 0.0125 to 0.05 and 0.025 to 0.125 μg/g, respectively. The recoveries and relative standard deviations of three basic colorants in six processed foods, namely, chili sauce, curry paste, gochujang (hot pepper paste), tandoori chicken (roasted chicken prepared with yogurt and spices), powder soup, and shrimp powder ranged from 70.2% to 102.8% and 0.8% to 8.0%, respectively. The intraday precision of the recovery test ranged from 1.7% to 4.5%, whereas the interday precision ranged from 3.7% to 7.7%. The reported method has been successfully applied to basic colorant determination in various processed foods such as fat-based food matrices (curry paste and tandoori chicken), chili products (gochujang and chili sauce), and protein-based products (shrimp powder and powder soup). Thin layer chromatography and liquid chromatography/mass spectrometry methods for the determination of basic colorants in processed foods were also developed for rapid analysis and identification, respectively. These methods are very useful for monitoring unauthorized basic colorants in inspection centers or quarantine laboratories in many countries.

Comparison of Classifiers for Decoding Sensory and Cognitive Information from Prefrontal Neuronal Populations

PubMed Central

Astrand, Elaine; Enel, Pierre; Ibos, Guilhem; Dominey, Peter Ford; Baraduc, Pierre; Ben Hamed, Suliann

2014-01-01

Decoding neuronal information is important in neuroscience, both as a basic means to understand how neuronal activity is related to cerebral function and as a processing stage in driving neuroprosthetic effectors. Here, we compare the readout performance of six commonly used classifiers at decoding two different variables encoded by the spiking activity of the non-human primate frontal eye fields (FEF): the spatial position of a visual cue, and the instructed orientation of the animal's attention. While the first variable is exogenously driven by the environment, the second variable corresponds to the interpretation of the instruction conveyed by the cue; it is endogenously driven and corresponds to the output of internal cognitive operations performed on the visual attributes of the cue. These two variables were decoded using either a regularized optimal linear estimator in its explicit formulation, an optimal linear artificial neural network estimator, a non-linear artificial neural network estimator, a non-linear naïve Bayesian estimator, a non-linear Reservoir recurrent network classifier or a non-linear Support Vector Machine classifier. Our results suggest that endogenous information such as the orientation of attention can be decoded from the FEF with the same accuracy as exogenous visual information. All classifiers did not behave equally in the face of population size and heterogeneity, the available training and testing trials, the subject's behavior and the temporal structure of the variable of interest. In most situations, the regularized optimal linear estimator and the non-linear Support Vector Machine classifiers outperformed the other tested decoders. PMID:24466019

Energy Accumulation and Emanation at Low Latitudes. Part II: Nonlinear Response to Strong Episodic Equatorial Forcing.

NASA Astrophysics Data System (ADS)

Chang, Hai-Ru; Webster, Peter J.

1990-11-01

A fully nonlinear model is used to reexamine the impact of a zonally varying basic state on the propagation characteristics of latitudinally equatorially trapped modes. Linear studies have shown that such modes are longitudinally trapped in regions of negative stretching deformation of the equatorial time-mean zonal flow (i.e., where Ux < 0) forming `accumulation' regions of wave action flux. Furthermore, the accumulation regions tend to act as local emanation regions to the extratropics. These physical communications between the tropics and extratropics are referred to as fast teleconnections due to their rapidity (periods of days to weeks) compared to the much slower climatological differences in the mean states such as occur between El Niño and La Niña. The latter form of communication between low and high latitudes, which is induced by very low frequency SST changes, is referred to as a slow teleconnection.It is generally found that accumulation and emanation regions are present in the nonlinear regime with much the same character as with the linear model. The similarity exists even when realistic forcing functions are used with amplitudes and temporal and spatial characteristics that correspond to impulsive convection in the western Pacific Ocean. A description of the convection is given. A diagnosis of the linear and nonlinear results shows that, in the tropics, the linear advection by the mean flow plays a dominant role and probably is the reason for the great similarity of the linear and nonlinear tropical atmosphere. However, there are some differences between the linear and nonlinear results. Nonlinear waves appear to propagate more rapidly through the maximum westerlies along the equator and with less difficulty than linear waves. The differences that do occur arise from the nonlinear changes in the tropical mass field, especially in the accumulation zone. Differences between linear and nonlinear responses in the midlatitude response to equatorial forcing appear to reflect changes in the tropics. Nonlinear maxima occur poleward of the region of tropical westerlies but only after accumulation has occurred along the equator.The results of the study are used to discuss the problem of why there is considerable similarity between simple linear models and more sophisticated nonlinear models. Such similarity would probably explain why the NMC and the NEPRF global models exhibit phase locked responses in the middle latitudes to imposed and impulsive tropical forcing. The role of fast teleconnenions in the longer term general circulation of the atmosphere is discussed, especially during El Niño and La Niña. Whereas an aggregate role for the fast teleconnections in producing very slowly evolving climate features remains obscure, it does appear that the accumulation-emanation theory may infer different routings for transient communications between the tropics and higher latitudes and vice vera depending upon the state of the basic flow.

Reconciling differences in stratospheric ozone composites

NASA Astrophysics Data System (ADS)

Ball, William T.; Alsing, Justin; Mortlock, Daniel J.; Rozanov, Eugene V.; Tummon, Fiona; Haigh, Joanna D.

2017-10-01

Observations of stratospheric ozone from multiple instruments now span three decades; combining these into composite datasets allows long-term ozone trends to be estimated. Recently, several ozone composites have been published, but trends disagree by latitude and altitude, even between composites built upon the same instrument data. We confirm that the main causes of differences in decadal trend estimates lie in (i) steps in the composite time series when the instrument source data changes and (ii) artificial sub-decadal trends in the underlying instrument data. These artefacts introduce features that can alias with regressors in multiple linear regression (MLR) analysis; both can lead to inaccurate trend estimates. Here, we aim to remove these artefacts using Bayesian methods to infer the underlying ozone time series from a set of composites by building a joint-likelihood function using a Gaussian-mixture density to model outliers introduced by data artefacts, together with a data-driven prior on ozone variability that incorporates knowledge of problems during instrument operation. We apply this Bayesian self-calibration approach to stratospheric ozone in 10° bands from 60° S to 60° N and from 46 to 1 hPa (˜ 21-48 km) for 1985-2012. There are two main outcomes: (i) we independently identify and confirm many of the data problems previously identified, but which remain unaccounted for in existing composites; (ii) we construct an ozone composite, with uncertainties, that is free from most of these problems - we call this the BAyeSian Integrated and Consolidated (BASIC) composite. To analyse the new BASIC composite, we use dynamical linear modelling (DLM), which provides a more robust estimate of long-term changes through Bayesian inference than MLR. BASIC and DLM, together, provide a step forward in improving estimates of decadal trends. Our results indicate a significant recovery of ozone since 1998 in the upper stratosphere, of both northern and southern midlatitudes, in all four composites analysed, and particularly in the BASIC composite. The BASIC results also show no hemispheric difference in the recovery at midlatitudes, in contrast to an apparent feature that is present, but not consistent, in the four composites. Our overall conclusion is that it is possible to effectively combine different ozone composites and account for artefacts and drifts, and that this leads to a clear and significant result that upper stratospheric ozone levels have increased since 1998, following an earlier decline.

Computational Modelling and Optimal Control of Ebola Virus Disease with non-Linear Incidence Rate

NASA Astrophysics Data System (ADS)

Takaidza, I.; Makinde, O. D.; Okosun, O. K.

2017-03-01

The 2014 Ebola outbreak in West Africa has exposed the need to connect modellers and those with relevant data as pivotal to better understanding of how the disease spreads and quantifying the effects of possible interventions. In this paper, we model and analyse the Ebola virus disease with non-linear incidence rate. The epidemic model created is used to describe how the Ebola virus could potentially evolve in a population. We perform an uncertainty analysis of the basic reproductive number R 0 to quantify its sensitivity to other disease-related parameters. We also analyse the sensitivity of the final epidemic size to the time control interventions (education, vaccination, quarantine and safe handling) and provide the cost effective combination of the interventions.

Complexity transitions in global algorithms for sparse linear systems over finite fields

NASA Astrophysics Data System (ADS)

Braunstein, A.; Leone, M.; Ricci-Tersenghi, F.; Zecchina, R.

2002-09-01

We study the computational complexity of a very basic problem, namely that of finding solutions to a very large set of random linear equations in a finite Galois field modulo q. Using tools from statistical mechanics we are able to identify phase transitions in the structure of the solution space and to connect them to the changes in the performance of a global algorithm, namely Gaussian elimination. Crossing phase boundaries produces a dramatic increase in memory and CPU requirements necessary for the algorithms. In turn, this causes the saturation of the upper bounds for the running time. We illustrate the results on the specific problem of integer factorization, which is of central interest for deciphering messages encrypted with the RSA cryptosystem.

3D Mueller-matrix mapping of biological optically anisotropic networks

NASA Astrophysics Data System (ADS)

Ushenko, O. G.; Ushenko, V. O.; Bodnar, G. B.; Zhytaryuk, V. G.; Prydiy, O. G.; Koval, G.; Lukashevich, I.; Vanchuliak, O.

2018-01-01

The paper consists of two parts. The first part presents short theoretical basics of the method of azimuthally-invariant Mueller-matrix description of optical anisotropy of biological tissues. It was provided experimentally measured coordinate distributions of Mueller-matrix invariants (MMI) of linear and circular birefringences of skeletal muscle tissue. It was defined the values of statistic moments, which characterize the distributions of amplitudes of wavelet coefficients of MMI at different scales of scanning. The second part presents the data of statistic analysis of the distributions of amplitude of wavelet coefficients of the distributions of linear birefringence of myocardium tissue died after the infarction and ischemic heart disease. It was defined the objective criteria of differentiation of the cause of death.

Multiscale polarization diagnostics of birefringent networks in problems of necrotic changes diagnostics

NASA Astrophysics Data System (ADS)

Sakhnovskiy, M. Yu.; Ushenko, Yu. O.; Ushenko, V. O.; Besaha, R. N.; Pavlyukovich, N.; Pavlyukovich, O.

2018-01-01

The paper consists of two parts. The first part presents short theoretical basics of the method of azimuthally-invariant Mueller-matrix description of optical anisotropy of biological tissues. It was provided experimentally measured coordinate distributions of Mueller-matrix invariants (MMI) of linear and circular birefringences of skeletal muscle tissue. It was defined the values of statistic moments, which characterize the distributions of amplitudes of wavelet coefficients of MMI at different scales of scanning. The second part presents the data of statistic analysis of the distributions of amplitude of wavelet coefficients of the distributions of linear birefringence of myocardium tissue died after the infarction and ischemic heart disease. It was defined the objective criteria of differentiation of the cause of death.

Wavelet analysis of birefringence images of myocardium tissue

NASA Astrophysics Data System (ADS)

Sakhnovskiy, M. Yu.; Ushenko, Yu. O.; Kushnerik, L.; Soltys, I. V.; Pavlyukovich, N.; Pavlyukovich, O.

2018-01-01

The paper consists of two parts. The first part presents short theoretical basics of the method of azimuthally-invariant Mueller-matrix description of optical anisotropy of biological tissues. It was provided experimentally measured coordinate distributions of Mueller-matrix invariants (MMI) of linear and circular birefringences of skeletal muscle tissue. It was defined the values of statistic moments, which characterize the distributions of amplitudes of wavelet coefficients of MMI at different scales of scanning. The second part presents the data of statistic analysis of the distributions of amplitude of wavelet coefficients of the distributions of linear birefringence of myocardium tissue died after the infarction and ischemic heart disease. It was defined the objective criteria of differentiation of the cause of death.

Code Samples Used for Complexity and Control

NASA Astrophysics Data System (ADS)

Ivancevic, Vladimir G.; Reid, Darryn J.

2015-11-01

The following sections are included: * MathematicaⓇ Code * Generic Chaotic Simulator * Vector Differential Operators * NLS Explorer * 2C++ Code * C++ Lambda Functions for Real Calculus * Accelerometer Data Processor * Simple Predictor-Corrector Integrator * Solving the BVP with the Shooting Method * Linear Hyperbolic PDE Solver * Linear Elliptic PDE Solver * Method of Lines for a Set of the NLS Equations * C# Code * Iterative Equation Solver * Simulated Annealing: A Function Minimum * Simple Nonlinear Dynamics * Nonlinear Pendulum Simulator * Lagrangian Dynamics Simulator * Complex-Valued Crowd Attractor Dynamics * Freeform Fortran Code * Lorenz Attractor Simulator * Complex Lorenz Attractor * Simple SGE Soliton * Complex Signal Presentation * Gaussian Wave Packet * Hermitian Matrices * Euclidean L2-Norm * Vector/Matrix Operations * Plain C-Code: Levenberg-Marquardt Optimizer * Free Basic Code: 2D Crowd Dynamics with 3000 Agents

Electron Interactions with Non-Linear Polyatomic Molecules and Their Radicals

DTIC Science & Technology

1993-12-01

developed which generates SCE quantities from molecular wave functions. This progress was realized in terms of some actual calculations on some molecules...section 4.A describes the basics of the Partial Differential Equation Theory; section 4.B describes the generalization to a finite element...Information Service (NTIS). At NTIS, it will be available to the general public, including foreign nations. This technical report has been reviewed and

UV-Vis spectroscopy of tyrosine side-groups in studies of protein structure. Part 1: basic principles and properties of tyrosine chromophore.

PubMed

Antosiewicz, Jan M; Shugar, David

Spectroscopic properties of tyrosine residues may be employed in structural studies of proteins. Here we discuss several different types of UV-Vis spectroscopy, like normal, difference and second-derivative UV absorption spectroscopy, fluorescence spectroscopy, linear and circular dichroism spectroscopy, and Raman spectroscopy, and corresponding optical properties of the tyrosine chromophore, phenol, which are used to study protein structure.

UV-Vis spectroscopy of tyrosine side-groups in studies of protein structure. Part 1: basic principles and properties of tyrosine chromophore.

PubMed

Antosiewicz, Jan M; Shugar, David

2016-06-01

Spectroscopic properties of tyrosine residues may be employed in structural studies of proteins. Here we discuss several different types of UV-Vis spectroscopy, like normal, difference and second-derivative UV absorption spectroscopy, fluorescence spectroscopy, linear and circular dichroism spectroscopy, and Raman spectroscopy, and corresponding optical properties of the tyrosine chromophore, phenol, which are used to study protein structure.

Numerical approach to optimal portfolio in a power utility regime-switching model

NASA Astrophysics Data System (ADS)

Gyulov, Tihomir B.; Koleva, Miglena N.; Vulkov, Lubin G.

2017-12-01

We consider a system of weakly coupled degenerate semi-linear parabolic equations of optimal portfolio in a regime-switching with power utility function, derived by A.R. Valdez and T. Vargiolu [14]. First, we discuss some basic properties of the solution of this system. Then, we develop and analyze implicit-explicit, flux limited finite difference schemes for the differential problem. Numerical experiments are discussed.

Basic Mechanisms of Radiation Effects in Electronic Materials and Devices

DTIC Science & Technology

1987-09-01

power as function of particle energy for electrons and protons Incident on silic,,n...8217-Mev 0000 Neutrons0 0 Fluenoe n/oma e 1-MeV equivalent fluenos n/orm DlSlLAOUMllW Ionizing radltlon O Stopping power (linear energy MeV/(g/om...from the interaction of radiation energy that goes Into ionization Is given by the stop- with electronic materials are Ionization (primarily ping power

A CCD Monolithic LMS Adaptive Analog Signal Processor Integrated Circuit.

DTIC Science & Technology

1980-03-01

adaptive filter with electrically- reprogrammable MOS analog conductance weights. I The analog and digital peripheral MOS on-chip circuits are provided with...electrically reprogrammable analog weights at tap positions along a CCD analog delay line in order to form a basic linear combiner for adaptive filtering...electrically reprogrammable analog conductance weights was introduced with the use of non-volatile MNOS memory 6-7 transistors biased in their triode

Optimally Scheduling Basic Courses at the Defense Language Institute using Integer Programming

DTIC Science & Technology

2005-09-01

DLI’s manual schedules at best can train 8%, 7% and 64%. 15. NUMBER OF PAGES 59 14. SUBJECT TERMS Operations Research, Linear Programming...class in 2006, 2007, and 2008, whereas DLI’s manual schedules at best can train 8%, 7% and 64%. vi THIS PAGE...ARABIC INSTRUTOR LEVELS .....................................25 FIGURE 2. OCS1 AND OCS2 CHINESE-MANDARIN INSTRUTOR LEVELS ............26 FIGURE 3

Three-dimensional to two-dimensional transition in mode-I fracture microbranching in a perturbed hexagonal close-packed lattice

NASA Astrophysics Data System (ADS)

Heizler, Shay I.; Kessler, David A.

2017-06-01

Mode-I fracture exhibits microbranching in the high velocity regime where the simple straight crack is unstable. For velocities below the instability, classic modeling using linear elasticity is valid. However, showing the existence of the instability and calculating the dynamics postinstability within the linear elastic framework is difficult and controversial. The experimental results give several indications that the microbranching phenomenon is basically a three-dimensional (3D) phenomenon. Nevertheless, the theoretical effort has been focused mostly on two-dimensional (2D) modeling. In this paper we study the microbranching instability using three-dimensional atomistic simulations, exploring the difference between the 2D and the 3D models. We find that the basic 3D fracture pattern shares similar behavior with the 2D case. Nevertheless, we exhibit a clear 3D-2D transition as the crack velocity increases, whereas as long as the microbranches are sufficiently small, the behavior is pure 3D behavior, whereas at large driving, as the size of the microbranches increases, more 2D-like behavior is exhibited. In addition, in 3D simulations, the quantitative features of the microbranches, separating the regimes of steady-state cracks (mirror) and postinstability (mist-hackle) are reproduced clearly, consistent with the experimental findings.

Adsorption of sulfur dioxide on ammonia-treated activated carbon fibers

USGS Publications Warehouse

Mangun, C.L.; DeBarr, J.A.; Economy, J.

2001-01-01

A series of activated carbon fibers (ACFs) and ammonia-treated ACFs prepared from phenolic fiber precursors have been studied to elucidate the role of pore size, pore volume, and pore surface chemistry on adsorption of sulfur dioxide and its catalytic conversion to sulfuric acid. As expected, the incorporation of basic functional groups into the ACFs was shown as an effective method for increasing adsorption of sulfur dioxide. The adsorption capacity for dry SO2 did not follow specific trends; however the adsorption energies calculated from the DR equation were found to increase linearly with nitrogen content for each series of ACFs. Much higher adsorption capacities were achieved for SO2 in the presence of oxygen and water due to its catalytic conversion to H2SO4. The dominant factor for increasing adsorption of SO2 from simulated flue gas for each series of fibers studied was the weight percent of basic nitrogen groups present. In addition, the adsorption energies calculated for dry SO2 were shown to be linearly related to the adsorption capacity of H2SO4 from this flue gas for all fibers. It was shown that optimization of this parameter along with the pore volume results in higher adsorption capacities for removal of SO2 from flue gases. ?? 2001 Elsevier Science Ltd. All rights reserved.

Representation of the quantum Fourier transform on multilevel basic elements by a sequence of selective rotation operators

NASA Astrophysics Data System (ADS)

Ermilov, A. S.; Zobov, V. E.

2007-12-01

To experimentally realize quantum computations on d-level basic elements (qudits) at d > 2, it is necessary to develop schemes for the technical realization of elementary logical operators. We have found sequences of selective rotation operators that represent the operators of the quantum Fourier transform (Walsh-Hadamard matrices) for d = 3-10. For the prime numbers 3, 5, and 7, the well-known method of linear algebra is applied, whereas, for the factorable numbers 6, 9, and 10, the representation of virtual spins is used (which we previously applied for d = 4, 8). Selective rotations can be realized, for example, by means of pulses of an RF magnetic field for systems of quadrupole nuclei or laser pulses for atoms and ions in traps.

Subcellular localization for Gram positive and Gram negative bacterial proteins using linear interpolation smoothing model.

PubMed

Saini, Harsh; Raicar, Gaurav; Dehzangi, Abdollah; Lal, Sunil; Sharma, Alok

2015-12-07

Protein subcellular localization is an important topic in proteomics since it is related to a protein׳s overall function, helps in the understanding of metabolic pathways, and in drug design and discovery. In this paper, a basic approximation technique from natural language processing called the linear interpolation smoothing model is applied for predicting protein subcellular localizations. The proposed approach extracts features from syntactical information in protein sequences to build probabilistic profiles using dependency models, which are used in linear interpolation to determine how likely is a sequence to belong to a particular subcellular location. This technique builds a statistical model based on maximum likelihood. It is able to deal effectively with high dimensionality that hinders other traditional classifiers such as Support Vector Machines or k-Nearest Neighbours without sacrificing performance. This approach has been evaluated by predicting subcellular localizations of Gram positive and Gram negative bacterial proteins. Copyright © 2015 Elsevier Ltd. All rights reserved.

Koopman operator theory: Past, present, and future

NASA Astrophysics Data System (ADS)

Brunton, Steven; Kaiser, Eurika; Kutz, Nathan

2017-11-01

Koopman operator theory has emerged as a dominant method to represent nonlinear dynamics in terms of an infinite-dimensional linear operator. The Koopman operator acts on the space of all possible measurement functions of the system state, advancing these measurements with the flow of the dynamics. A linear representation of nonlinear dynamics has tremendous potential to enable the prediction, estimation, and control of nonlinear systems with standard textbook methods developed for linear systems. Dynamic mode decomposition has become the leading data-driven method to approximate the Koopman operator, although there are still open questions and challenges around how to obtain accurate approximations for strongly nonlinear systems. This talk will provide an introductory overview of modern Koopman operator theory, reviewing the basics and describing recent theoretical and algorithmic developments. Particular emphasis will be placed on the use of data-driven Koopman theory to characterize and control high-dimensional fluid dynamic systems. This talk will also address key advances in the rapidly growing fields of machine learning and data science that are likely to drive future developments.

The azimuthal component of Poynting's vector and the angular momentum of light

NASA Astrophysics Data System (ADS)

Cameron, Robert P.; Speirits, Fiona C.; Gilson, Claire R.; Allen, L.; Barnett, Stephen M.

2015-12-01

The usual description in basic electromagnetic theory of the linear and angular momenta of light is centred upon the identification of Poynting's vector as the linear momentum density and its cross product with position, or azimuthal component, as the angular momentum density. This seemingly reasonable approach brings with it peculiarities, however, in particular with regards to the separation of angular momentum into orbital and spin contributions, which has sometimes been regarded as contrived. In the present paper, we observe that densities are not unique, which leads us to ask whether the usual description is, in fact, the most natural choice. To answer this, we adopt a fundamental rather than heuristic approach by first identifying appropriate symmetries of Maxwell's equations and subsequently applying Noether's theorem to obtain associated conservation laws. We do not arrive at the usual description. Rather, an equally acceptable one in which the relationship between linear and angular momenta is nevertheless more subtle and in which orbital and spin contributions emerge separately and with transparent forms.

A python framework for environmental model uncertainty analysis

USGS Publications Warehouse

White, Jeremy; Fienen, Michael N.; Doherty, John E.

2016-01-01

We have developed pyEMU, a python framework for Environmental Modeling Uncertainty analyses, open-source tool that is non-intrusive, easy-to-use, computationally efficient, and scalable to highly-parameterized inverse problems. The framework implements several types of linear (first-order, second-moment (FOSM)) and non-linear uncertainty analyses. The FOSM-based analyses can also be completed prior to parameter estimation to help inform important modeling decisions, such as parameterization and objective function formulation. Complete workflows for several types of FOSM-based and non-linear analyses are documented in example notebooks implemented using Jupyter that are available in the online pyEMU repository. Example workflows include basic parameter and forecast analyses, data worth analyses, and error-variance analyses, as well as usage of parameter ensemble generation and management capabilities. These workflows document the necessary steps and provides insights into the results, with the goal of educating users not only in how to apply pyEMU, but also in the underlying theory of applied uncertainty quantification.

Using NCAP to predict RFI effects in linear bipolar integrated circuits

NASA Astrophysics Data System (ADS)

Fang, T.-F.; Whalen, J. J.; Chen, G. K. C.

1980-11-01

Applications of the Nonlinear Circuit Analysis Program (NCAP) to calculate RFI effects in electronic circuits containing discrete semiconductor devices have been reported upon previously. The objective of this paper is to demonstrate that the computer program NCAP also can be used to calcuate RFI effects in linear bipolar integrated circuits (IC's). The IC's reported upon are the microA741 operational amplifier (op amp) which is one of the most widely used IC's, and a differential pair which is a basic building block in many linear IC's. The microA741 op amp was used as the active component in a unity-gain buffer amplifier. The differential pair was used in a broad-band cascode amplifier circuit. The computer program NCAP was used to predict how amplitude-modulated RF signals are demodulated in the IC's to cause undesired low-frequency responses. The predicted and measured results for radio frequencies in the 0.050-60-MHz range are in good agreement.

Onset of Turbulence in a Pipe

NASA Astrophysics Data System (ADS)

Böberg, L.; Brösa, U.

1988-09-01

Turbulence in a pipe is derived directly from the Navier-Stokes equation. Analysis of numerical simulations revealed that small disturbances called 'mothers' induce other much stronger disturbances called 'daughters'. Daughters determine the look of turbulence, while mothers control the transfer of energy from the basic flow to the turbulent motion. From a practical point of view, ruling mothers means ruling turbulence. For theory, the mother-daughter process represents a mechanism permitting chaotic motion in a linearly stable system. The mechanism relies on a property of the linearized problem according to which the eigenfunctions become more and more collinear as the Reynolds number increases. The mathematical methods are described, comparisons with experiments are made, mothers and daughters are analyzed, also graphically, with full particulars, and the systematic construction of small systems of differential equations to mimic the non-linear process by means as simple as possible is explained. We suggest that more then 20 but less than 180 essential degrees of freedom take part in the onset of turbulence.

Separation and reconstruction of high pressure water-jet reflective sound signal based on ICA

NASA Astrophysics Data System (ADS)

Yang, Hongtao; Sun, Yuling; Li, Meng; Zhang, Dongsu; Wu, Tianfeng

2011-12-01

The impact of high pressure water-jet on the different materials target will produce different reflective mixed sound. In order to reconstruct the reflective sound signals distribution on the linear detecting line accurately and to separate the environment noise effectively, the mixed sound signals acquired by linear mike array were processed by ICA. The basic principle of ICA and algorithm of FASTICA were described in detail. The emulation experiment was designed. The environment noise signal was simulated by using band-limited white noise and the reflective sound signal was simulated by using pulse signal. The reflective sound signal attenuation produced by the different distance transmission was simulated by weighting the sound signal with different contingencies. The mixed sound signals acquired by linear mike array were synthesized by using the above simulated signals and were whitened and separated by ICA. The final results verified that the environment noise separation and the reconstruction of the detecting-line sound distribution can be realized effectively.

Longitudinal aerodynamic characteristics of a wing-winglet model designed at M = 0.8, C sub L = 0.4 using linear aerodynamic theory

NASA Technical Reports Server (NTRS)

Kuhlman, J. M.

1983-01-01

Wind tunnel test results have been presented herein for a subsonic transport type wing fitted with winglets. Wind planform was chosen to be representative of wings used on current jet transport aircraft, while wing and winglet camber surfaces were designed using two different linear aerodynamic design methods. The purpose of the wind tunnel investigation was to determine the effectiveness of these linear aerodynamic design computer codes in designing a non-planar transport configuration which would cruise efficiently. The design lift coefficient was chosen to be 0.4, at a design Mach number of 0.8. Force and limited pressure data were obtained for the basic wing, and for the wing fitted with the two different winglet designs, at Mach numbers of 0.60, 0.70, 0.75 and 0.80 over an angle of attack range of -2 to +6 degrees, at zero sideslip. The data have been presented without analysis to expedite publication.

Going virtual with quicktime VR: new methods and standardized tools for interactive dynamic visualization of anatomical structures.

PubMed

Trelease, R B; Nieder, G L; Dørup, J; Hansen, M S

2000-04-15

Continuing evolution of computer-based multimedia technologies has produced QuickTime, a multiplatform digital media standard that is supported by stand-alone commercial programs and World Wide Web browsers. While its core functions might be most commonly employed for production and delivery of conventional video programs (e.g., lecture videos), additional QuickTime VR "virtual reality" features can be used to produce photorealistic, interactive "non-linear movies" of anatomical structures ranging in size from microscopic through gross anatomic. But what is really included in QuickTime VR and how can it be easily used to produce novel and innovative visualizations for education and research? This tutorial introduces the QuickTime multimedia environment, its QuickTime VR extensions, basic linear and non-linear digital video technologies, image acquisition, and other specialized QuickTime VR production methods. Four separate practical applications are presented for light and electron microscopy, dissectable preserved specimens, and explorable functional anatomy in magnetic resonance cinegrams.

Design and optimization of a Holweck pump via linear kinetic theory

NASA Astrophysics Data System (ADS)

Naris, Steryios; Koutandou, Eirini; Valougeorgis, Dimitris

2012-05-01

The Holweck pump is widely used in the vacuum pumping industry. It can be a self standing apparatus or it can be part of a more advanced pumping system. It is composed by an inner rotating cylinder (rotor) and an outer stationary cylinder (stator). One of them, has spiral guided grooves resulting to a gas motion from the high towards the low vacuum port. Vacuum pumps may be simulated by the DSMC method but due to the involved high computational cost in many cases manufactures commonly resort to empirical formulas and experimental data. Recently a computationally efficient simulation of the Holweck pump via linear kinetic theory has been proposed by Sharipov et al [1]. Neglecting curvature and end effects the gas flow configuration through the helicoidal channels is decomposed into four basic flows. They correspond to pressure and boundary driven flows through a grooved channel and through a long channel with a T shape cross section. Although the formulation and the methodology are explained in detail, results are very limited and more important they are presented in a normalized way which does not provide the needed information about the pump performance in terms of the involved geometrical and flow parameters. In the present work the four basic flows are solved numerically based on the linearized BGK model equation subjected to diffuse boundary conditions. The results obtained are combined in order to create a database of the flow characteristics for a large spectrum of the rarefaction parameter and various geometrical configurations. Based on this database the performance characteristics which are critical in the design of the Holweck pump are computed and the design parameters such as the angle of the pump and the rotational speed, are optimized. This modeling may be extended to other vacuum pumps.

Spectrophotometric determination of basic fuchsin from various water samples after vortex assisted solid phase extraction using reduced graphene oxide as an adsorbent.

PubMed

Tokalıoğlu, Şerife; Yavuz, Emre; Aslantaş, Ayşe; Şahan, Halil; Taşkın, Ferhat; Patat, Şaban

2015-01-01

In this study, a fast and simple vortex assisted solid phase extraction method was developed for the separation/preconcentration of basic fuchsin in various water samples. The determination of basic fuchsin was carried out at a wavelength of 554 nm by spectrophotometry. Reduced graphene oxide which was used as a solid phase extractor was synthesized and characterized by X-ray diffraction, scanning electron microscopy and the Brunauer, Emmett and Teller. The optimum conditions are as follows: pH 2, contact times for adsorption and elution of 30 s and 90 s, respectively, 10 mg adsorbent, and eluent (ethanol) volume of 1 mL. The effects of some interfering ions and dyes were investigated. The method was linear in the concentration range of 50-250 μg L(-1). The adsorption capacity was 34.1 mg g(-1). The preconcentration factor, limit of detection and precision (RSD, %) of the method were found to be 400, 0.07 μg L(-1) and 1.2%, respectively. The described method was validated by analyzing basic fuchsin spiked certified reference material (SPS-WW1 Batch 114-Wastewater) and spiked real water samples. Copyright © 2015 Elsevier B.V. All rights reserved.

Effect of charge on the conformation of highly basic peptides including the tail regions of histone proteins by ion mobility mass spectrometry.

PubMed

Akashi, Satoko; Downard, Kevin M

2016-09-01

The first systematic and comprehensive study of the charging behaviour and effect of charge on the conformation of specifically constructed arginine-rich peptides and its significance to the N- and C-terminal basic tail regions of histone proteins was conducted using ion mobility mass spectrometry (IM-MS). Among the basic amino acids, arginine has the greatest impact on the charging behaviour and structures of gas phase ions by virtue of its high proton affinity. A close linear correlation was found between either the maximum charge, or most abundant charge state, that the peptides support and their average collision cross section (CCS) values measured by ion mobility mass spectrometry. The calculated collision cross sections for the lowest energy solution state models predicted by the PEP-FOLD algorithm using a modified MOBCAL trajectory method were found to best correlate with the values measured by IM-MS. In the case of the histone peptides, more compact folded structures, supporting less than the maximum number of charges, were observed. These results are consistent with those previously reported for histone dimers where neutralization of the charge at the basic residues of the tail regions did not affect their CCS values.

A systematic linear space approach to solving partially described inverse eigenvalue problems

NASA Astrophysics Data System (ADS)

Hu, Sau-Lon James; Li, Haujun

2008-06-01

Most applications of the inverse eigenvalue problem (IEP), which concerns the reconstruction of a matrix from prescribed spectral data, are associated with special classes of structured matrices. Solving the IEP requires one to satisfy both the spectral constraint and the structural constraint. If the spectral constraint consists of only one or few prescribed eigenpairs, this kind of inverse problem has been referred to as the partially described inverse eigenvalue problem (PDIEP). This paper develops an efficient, general and systematic approach to solve the PDIEP. Basically, the approach, applicable to various structured matrices, converts the PDIEP into an ordinary inverse problem that is formulated as a set of simultaneous linear equations. While solving simultaneous linear equations for model parameters, the singular value decomposition method is applied. Because of the conversion to an ordinary inverse problem, other constraints associated with the model parameters can be easily incorporated into the solution procedure. The detailed derivation and numerical examples to implement the newly developed approach to symmetric Toeplitz and quadratic pencil (including mass, damping and stiffness matrices of a linear dynamic system) PDIEPs are presented. Excellent numerical results for both kinds of problem are achieved under the situations that have either unique or infinitely many solutions.

Design and laboratory testing of a prototype linear temperature sensor

NASA Astrophysics Data System (ADS)

Dube, C. M.; Nielsen, C. M.

1982-07-01

This report discusses the basic theory, design, and laboratory testing of a prototype linear temperature sensor (or "line sensor'), which is an instrument for measuring internal waves in the ocean. The operating principle of the line sensor consists of measuring the average resistance change of a vertically suspended wire (or coil of wire) induced by the passage of an internal wave in a thermocline. The advantage of the line sensor over conventional internal wave measurement techniques is that it is insensitive to thermal finestructure which contaminates point sensor measurements, and its output is approximately linearly proportional to the internal wave displacement. An approximately one-half scale prototype line sensor module was teste in the laboratory. The line sensor signal was linearly related to the actual fluid displacement to within 10%. Furthermore, the absolute output was well predicted (within 25%) from the theoretical model and the sensor material properties alone. Comparisons of the line sensor and a point sensor in a wavefield with superimposed turbulence (finestructure) revealed negligible distortion in the line sensor signal, while the point sensor signal was swamped by "turbulent noise'. The effects of internal wave strain were also found to be negligible.

Dopamine-dependent non-linear correlation between subthalamic rhythms in Parkinson's disease.

PubMed

Marceglia, S; Foffani, G; Bianchi, A M; Baselli, G; Tamma, F; Egidi, M; Priori, A

2006-03-15

The basic information architecture in the basal ganglia circuit is under debate. Whereas anatomical studies quantify extensive convergence/divergence patterns in the circuit, suggesting an information sharing scheme, neurophysiological studies report an absence of linear correlation between single neurones in normal animals, suggesting a segregated parallel processing scheme. In 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated monkeys and in parkinsonian patients single neurones become linearly correlated, thus leading to a loss of segregation between neurones. Here we propose a possible integrative solution to this debate, by extending the concept of functional segregation from the cellular level to the network level. To this end, we recorded local field potentials (LFPs) from electrodes implanted for deep brain stimulation (DBS) in the subthalamic nucleus (STN) of parkinsonian patients. By applying bispectral analysis, we found that in the absence of dopamine stimulation STN LFP rhythms became non-linearly correlated, thus leading to a loss of segregation between rhythms. Non-linear correlation was particularly consistent between the low-beta rhythm (13-20 Hz) and the high-beta rhythm (20-35 Hz). Levodopa administration significantly decreased these non-linear correlations, therefore increasing segregation between rhythms. These results suggest that the extensive convergence/divergence in the basal ganglia circuit is physiologically necessary to sustain LFP rhythms distributed in large ensembles of neurones, but is not sufficient to induce correlated firing between neurone pairs. Conversely, loss of dopamine generates pathological linear correlation between neurone pairs, alters the patterns within LFP rhythms, and induces non-linear correlation between LFP rhythms operating at different frequencies. The pathophysiology of information processing in the human basal ganglia therefore involves not only activities of individual rhythms, but also interactions between rhythms.

Dopamine-dependent non-linear correlation between subthalamic rhythms in Parkinson's disease

PubMed Central

Marceglia, S; Foffani, G; Bianchi, A M; Baselli, G; Tamma, F; Egidi, M; Priori, A

2006-01-01

The basic information architecture in the basal ganglia circuit is under debate. Whereas anatomical studies quantify extensive convergence/divergence patterns in the circuit, suggesting an information sharing scheme, neurophysiological studies report an absence of linear correlation between single neurones in normal animals, suggesting a segregated parallel processing scheme. In 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated monkeys and in parkinsonian patients single neurones become linearly correlated, thus leading to a loss of segregation between neurones. Here we propose a possible integrative solution to this debate, by extending the concept of functional segregation from the cellular level to the network level. To this end, we recorded local field potentials (LFPs) from electrodes implanted for deep brain stimulation (DBS) in the subthalamic nucleus (STN) of parkinsonian patients. By applying bispectral analysis, we found that in the absence of dopamine stimulation STN LFP rhythms became non-linearly correlated, thus leading to a loss of segregation between rhythms. Non-linear correlation was particularly consistent between the low-beta rhythm (13–20 Hz) and the high-beta rhythm (20–35 Hz). Levodopa administration significantly decreased these non-linear correlations, therefore increasing segregation between rhythms. These results suggest that the extensive convergence/divergence in the basal ganglia circuit is physiologically necessary to sustain LFP rhythms distributed in large ensembles of neurones, but is not sufficient to induce correlated firing between neurone pairs. Conversely, loss of dopamine generates pathological linear correlation between neurone pairs, alters the patterns within LFP rhythms, and induces non-linear correlation between LFP rhythms operating at different frequencies. The pathophysiology of information processing in the human basal ganglia therefore involves not only activities of individual rhythms, but also interactions between rhythms. PMID:16410285

Charge heterogeneity: Basic antibody charge variants with increased binding to Fc receptors.

PubMed

Hintersteiner, Beate; Lingg, Nico; Zhang, Peiqing; Woen, Susanto; Hoi, Kong Meng; Stranner, Stefan; Wiederkum, Susanne; Mutschlechner, Oliver; Schuster, Manfred; Loibner, Hans; Jungbauer, Alois

We identified active isoforms of the chimeric anti-GD2 antibody, ch14.18, a recombinant antibody produced in Chinese hamster ovary cells, which is already used in clinical trials. 1,2,3 We separated the antibody by high resolution ion-exchange chromatography with linear pH gradient elution into acidic, main and basic charge variants on a preparative scale yielding enough material for an in-depth study of the sources and the effects of microheterogeneity. The binding affinity of the charge variants toward the antigen and various cell surface receptors was studied by Biacore. Effector functions were evaluated using cellular assays for antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity. Basic charge variants showed increased binding to cell surface receptor FcγRIIIa, which plays a major role in regulating effector functions. Furthermore, increased binding of the basic fractions to the neonatal receptor was observed. As this receptor mediates the prolonged half-life of IgG in human serum, this data may well hint at an increased serum half-life of these basic variants compared to their more acidic counterparts. Different glycoform patterns, C-terminal lysine clipping and N-terminal pyroglutamate formation were identified as the main structural sources for the observed isoform pattern. Potential differences in structural stability between individual charge variant fractions by nano differential scanning calorimetry could not been detected. Our in-vitro data suggests that the connection between microheterogeneity and the biological activity of recombinant antibody therapeutics deserves more attention than commonly accepted.

Nurse Practitioners' Use of Communication Techniques: Results of a Maryland Oral Health Literacy Survey

PubMed Central

Koo, Laura W.; Horowitz, Alice M.; Radice, Sarah D.; Wang, Min Q.; Kleinman, Dushanka V.

2016-01-01

Objectives We examined nurse practitioners’ use and opinions of recommended communication techniques for the promotion of oral health as part of a Maryland state-wide oral health literacy assessment. Use of recommended health-literate and patient-centered communication techniques have demonstrated improved health outcomes. Methods A 27-item self-report survey, containing 17 communication technique items, across 5 domains, was mailed to 1,410 licensed nurse practitioners (NPs) in Maryland in 2010. Use of communication techniques and opinions about their effectiveness were analyzed using descriptive statistics. General linear models explored provider and practice characteristics to predict differences in the total number and the mean number of communication techniques routinely used in a week. Results More than 80% of NPs (N = 194) routinely used 3 of the 7 basic communication techniques: simple language, limiting teaching to 2–3 concepts, and speaking slowly. More than 75% of respondents believed that 6 of the 7 basic communication techniques are effective. Sociodemographic provider characteristics and practice characteristics were not significant predictors of the mean number or the total number of communication techniques routinely used by NPs in a week. Potential predictors for using more of the 7 basic communication techniques, demonstrating significance in one general linear model each, were: assessing the office for user-friendliness and ever taking a communication course in addition to nursing school. Conclusions NPs in Maryland self-reported routinely using some recommended health-literate communication techniques, with belief in their effectiveness. Our findings suggest that NPs who had assessed the office for patient-friendliness or who had taken a communication course beyond their initial education may be predictors for using more of the 7 basic communication techniques. These self-reported findings should be validated with observational studies. Graduate and continuing education for NPs should increase emphasis on health-literate and patient-centered communication techniques to increase patient understanding of dental caries prevention. Non-dental healthcare providers, such as NPs, are uniquely positioned to contribute to preventing early childhood dental caries through health-literate and patient-centered communication. PMID:26766557

Nurse Practitioners' Use of Communication Techniques: Results of a Maryland Oral Health Literacy Survey.

PubMed

Koo, Laura W; Horowitz, Alice M; Radice, Sarah D; Wang, Min Q; Kleinman, Dushanka V

2016-01-01

We examined nurse practitioners' use and opinions of recommended communication techniques for the promotion of oral health as part of a Maryland state-wide oral health literacy assessment. Use of recommended health-literate and patient-centered communication techniques have demonstrated improved health outcomes. A 27-item self-report survey, containing 17 communication technique items, across 5 domains, was mailed to 1,410 licensed nurse practitioners (NPs) in Maryland in 2010. Use of communication techniques and opinions about their effectiveness were analyzed using descriptive statistics. General linear models explored provider and practice characteristics to predict differences in the total number and the mean number of communication techniques routinely used in a week. More than 80% of NPs (N = 194) routinely used 3 of the 7 basic communication techniques: simple language, limiting teaching to 2-3 concepts, and speaking slowly. More than 75% of respondents believed that 6 of the 7 basic communication techniques are effective. Sociodemographic provider characteristics and practice characteristics were not significant predictors of the mean number or the total number of communication techniques routinely used by NPs in a week. Potential predictors for using more of the 7 basic communication techniques, demonstrating significance in one general linear model each, were: assessing the office for user-friendliness and ever taking a communication course in addition to nursing school. NPs in Maryland self-reported routinely using some recommended health-literate communication techniques, with belief in their effectiveness. Our findings suggest that NPs who had assessed the office for patient-friendliness or who had taken a communication course beyond their initial education may be predictors for using more of the 7 basic communication techniques. These self-reported findings should be validated with observational studies. Graduate and continuing education for NPs should increase emphasis on health-literate and patient-centered communication techniques to increase patient understanding of dental caries prevention. Non-dental healthcare providers, such as NPs, are uniquely positioned to contribute to preventing early childhood dental caries through health-literate and patient-centered communication.

Ten-year longitudinal trajectories of older adults' basic and everyday cognitive abilities.

PubMed

Yam, Anna; Gross, Alden L; Prindle, John J; Marsiske, Michael

2014-11-01

To examine the longitudinal trajectories of everyday cognition and longitudinal associations with basic (i.e., laboratory and experimentally measured) cognitive abilities, including verbal memory, inductive reasoning, visual processing speed, and vocabulary. Participants were healthy older adults drawn from the no-treatment control group (N = 698) of the Advanced Cognitive Training for the Independent and Vital Elderly (Willis et al., 2006) randomized trial and were assessed at baseline and 1, 2, 3, 5, and 10 years later. Analyses were conducted using latent growth models. Modeling revealed an overall inverted-U shape (quadratic) trajectory across cognitive domains. Among basic cognitive predictors, level and slope in reasoning demonstrated the closest association to level and slope of everyday cognition, and accounted for most of the individual differences in linear gain in everyday cognition. Everyday cognition is not buffered against decline, and is most closely related to inductive reasoning in healthy older adults. To establish the clinical utility of everyday cognitive measures, future research should examine these associations in samples with more cognitive impairment. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Mathematical foundations of biomechanics.

PubMed

Niederer, Peter F

2010-01-01

The aim of biomechanics is the analysis of the structure and function of humans, animals, and plants by means of the methods of mechanics. Its foundations are in particular embedded in mathematics, physics, and informatics. Due to the inherent multidisciplinary character deriving from its aim, biomechanics has numerous connections and overlapping areas with biology, biochemistry, physiology, and pathophysiology, along with clinical medicine, so its range is enormously wide. This treatise is mainly meant to serve as an introduction and overview for readers and students who intend to acquire a basic understanding of the mathematical principles and mechanics that constitute the foundation of biomechanics; accordingly, its contents are limited to basic theoretical principles of general validity and long-range significance. Selected examples are included that are representative for the problems treated in biomechanics. Although ultimate mathematical generality is not in the foreground, an attempt is made to derive the theory from basic principles. A concise and systematic formulation is thereby intended with the aim that the reader is provided with a working knowledge. It is assumed that he or she is familiar with the principles of calculus, vector analysis, and linear algebra.

Estimation of wing nonlinear aerodynamic characteristics at supersonic speeds

NASA Technical Reports Server (NTRS)

Carlson, H. W.; Mack, R. J.

1980-01-01

A computational system for estimation of nonlinear aerodynamic characteristics of wings at supersonic speeds was developed and was incorporated in a computer program. This corrected linearized theory method accounts for nonlinearities in the variation of basic pressure loadings with local surface slopes, predicts the degree of attainment of theoretical leading edge thrust, and provides an estimate of detached leading edge vortex loadings that result when the theoretical thrust forces are not fully realized.

Simulation studies of plasma waves in the electron foreshock - The generation of Langmuir waves by a gentle bump-on-tail electron distribution

NASA Technical Reports Server (NTRS)

Dum, C. T.

1990-01-01

Particle simulation experiments were used to study the basic physical ingredients needed for building a global model of foreshock wave phenomena. In particular, the generation of Langmuir waves by a gentle bump-on-tail electron distribution is analyzed. It is shown that, with appropriately designed simulations experiments, quasi-linear theory can be quantitatively verified for parameters corresponding to the electron foreshock.

Air Force Operational Test and Evaluation Center, Volume 2, Number 2

DTIC Science & Technology

1988-01-01

the special class of attributes arc recorded, cost or In place of the normalization ( I). we propose beliefit. the lollowins normalization NUMERICAL ...comprchcnsi\\c set of modular basic data flow to meet requirements at test tools ,. designed to provide flexible data reduction start, then building to...possible. a totlinaion ot the two position error measurement techniques arc used SLR is a methd of fitting a linear model o accumlulate a position error

Assembly of Ultra-Dense Nanowire-Based Computing Systems

DTIC Science & Technology

2006-06-30

34* characterized basic device element properties and statistics "* demonstrated product of sums (POS) validating assembled 2-bit adder structures " Demonstrated...linear region (Vds= 10 mV) from the peak g = 3 jiS at IVg -VTI= 0.13 V using the charge control model, representsmore than a factor of 10 improvement over...disrupted by ionizing particles or thermal fluctuation. Further, when working with such small charges, it is statistically possible that logic

Photon Limited Images and Their Restoration

DTIC Science & Technology

1976-03-01

arises from noise inherent in the detected image data. In the first part of this report a model is developed which can be used to mathematically and...statistically describe an image detected at low light levels. This rodel serves to clarify some basic properties of photon noise , and provides a basis...for the analysi.s of image restoration. In the second part the problem of linear least-square restoration of imagery limited by photon noise is

Aircraft model prototypes which have specified handling-quality time histories

NASA Technical Reports Server (NTRS)

Johnson, S. H.

1976-01-01

Several techniques for obtaining linear constant-coefficient airplane models from specified handling-quality time histories are discussed. One technique, the pseudodata method, solves the basic problem, yields specified eigenvalues, and accommodates state-variable transfer-function zero suppression. The method is fully illustrated for a fourth-order stability-axis small-motion model with three lateral handling-quality time histories specified. The FORTRAN program which obtains and verifies the model is included and fully documented.

Rank-k modification methods for recursive least squares problems

NASA Astrophysics Data System (ADS)

Olszanskyj, Serge; Lebak, James; Bojanczyk, Adam

1994-09-01

In least squares problems, it is often desired to solve the same problem repeatedly but with several rows of the data either added, deleted, or both. Methods for quickly solving a problem after adding or deleting one row of data at a time are known. In this paper we introduce fundamental rank-k updating and downdating methods and show how extensions of rank-1 downdating methods based on LINPACK, Corrected Semi-Normal Equations (CSNE), and Gram-Schmidt factorizations, as well as new rank-k downdating methods, can all be derived from these fundamental results. We then analyze the cost of each new algorithm and make comparisons tok applications of the corresponding rank-1 algorithms. We provide experimental results comparing the numerical accuracy of the various algorithms, paying particular attention to the downdating methods, due to their potential numerical difficulties for ill-conditioned problems. We then discuss the computation involved for each downdating method, measured in terms of operation counts and BLAS calls. Finally, we provide serial execution timing results for these algorithms, noting preferable points for improvement and optimization. From our experiments we conclude that the Gram-Schmidt methods perform best in terms of numerical accuracy, but may be too costly for serial execution for large problems.

High-performance analysis of filtered semantic graphs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Buluc, Aydin; Fox, Armando; Gilbert, John R.

2012-01-01

High performance is a crucial consideration when executing a complex analytic query on a massive semantic graph. In a semantic graph, vertices and edges carry "attributes" of various types. Analytic queries on semantic graphs typically depend on the values of these attributes; thus, the computation must either view the graph through a filter that passes only those individual vertices and edges of interest, or else must first materialize a subgraph or subgraphs consisting of only the vertices and edges of interest. The filtered approach is superior due to its generality, ease of use, and memory efficiency, but may carry amore » performance cost. In the Knowledge Discovery Toolbox (KDT), a Python library for parallel graph computations, the user writes filters in a high-level language, but those filters result in relatively low performance due to the bottleneck of having to call into the Python interpreter for each edge. In this work, we use the Selective Embedded JIT Specialization (SEJITS) approach to automatically translate filters defined by programmers into a lower-level efficiency language, bypassing the upcall into Python. We evaluate our approach by comparing it with the high-performance C++ /MPI Combinatorial BLAS engine, and show that the productivity gained by using a high-level filtering language comes without sacrificing performance.« less

Role of basicity and tetrahedral speciation in controlling the thermodynamic properties of silicate liquids, part 1: the system CaO-MgO-Al 2O 3-SiO 2

NASA Astrophysics Data System (ADS)

Beckett, John R.

2002-01-01

Activity coefficients of oxide components in the system CaO-MgO-Al2O3-SiO2 (CMAS) were calculated with the model of Berman (Berman R. G., ;A thermodynamic model for multicomponent melts with application to the system CaO-MgO-Al2O3-SiO2,; Ph.D. dissertation, University of British Columbia, 1983) and used to explore large-scale relationships among these variables and between them and the liquid composition. On the basis of Berman's model, the natural logarithm of the activity coefficient of MgO, ln(γMgOLiq), and ln(γMgOLiq/γSiO2Liq) are nearly linear functions of ln(γCaOLiq). All three of these variables are simple functions of the optical basicity Λ with which they display minima near Λ ∼ 0.54 that are generated by liquids with low ratios of nonbridging to tetrahedral oxygens (NBO/T) (<0.3) and a mole fraction ratio, XSiO2Liq/XAl2O3Liq, in the range 4 to 20. Variations in ln(γCaOLiq) at constant Λ near the minimum are due mostly to liquids with (XCaOLiq + XMgOLiq)/XAl2O3Liq < 1. The correlations with optical basicity imply that the electron donor power is an important factor in determining the thermodynamic properties of aluminosilicate liquids. For a constant NBO/T, ln(γCaOLiq/γAl2O3Liq) and ln(γMgOLiqγAl2O3Liq) form curves in terms of XSiO2Liq/XAl2O3Liq. The same liquids that generate minima in the Λ plots are also associated with minima in ln(γCaOLiqγAl2O3Liq) and ln(γMgOLiqγAl2O3Liq) as a function of XSiO2Liq/XAl2O3Liq. In addition, there are maxima or sharp changes in slope for NBO/T > 0.3, which occur for XSiO2Liq/XAl2O3Liq ranging from ∼0 to ∼6 and increase with increasing NBO/T. The systematic variations in activity coefficients as a function of composition and optical basicity reflect underlying shifts in speciation as the composition of the liquid is changed. On the basis of correlations among the activity coefficients, it is likely that the use of CaO, an exchange component such as SiMg-1 and two of MgO, CaAl2O4, or MgAl2O4 would yield significant savings in the number of parameters required to model the excess free energy surface of liquids over large portions of CMAS relative to the use of oxide end members. Systematic behavior of thermodynamic properties extends to small amounts of other elements dissolved in otherwise CMAS liquids. For example, ln(XFe2+Liq/XFe3+Liq) at constant oxygen fugacity is linearly correlated with ln(γCaOLiq). Similarly, ln(CS), where CS is the sulfide capacity is linearly correlated at constant temperature with each of the optical basicity, ln(aCaOLiq) and ln(γCaOLiq), although the correlation for the latter breaks down for low values of Λ. The well-known systematic behavior of sulfide capacity as a function of optical basicity for systems inside as well as outside CMAS suggests that ln(γCaSLiq) is also a simple function of optical basicity and that the relationships observed among the activity coefficients in CMAS may hold for more complex systems.

Convective instabilities of electromagnetic ion cyclotron waves in the outer magnetosphere

NASA Technical Reports Server (NTRS)

Horne, Richard B.; Thorne, Richard M.

1994-01-01

The path-integrated linear growth of electromagnetic ion cyclotron waves in the outer (L is greater than or equal to 7) magnetosphere is investigated using a realistic thermal plasma distribution with an additional anisotropic energetic ring current H(+) to provide free energy for instability. The results provide a realistic simulation of the recent Active Magneto- spheric Particle Tracer Explorers (AMPTE) observations. For conditions typical of the dayside magnetosphere, high plasma beta effects reduce the group velocity and significantly increase the spatial growth rates for left-handed polarized instabilities just below the helium gyrofrequency Omega(sub He(+)), and on the guided mode above Omega(sub He(+)) but below the cross over frequency omega(sub cr). Relatively high densities, typical of the afternoon local time sector, favor these low group velocity effects for predominantly field-aligned waves. Lower densities, typical of those found in the early morning local time sector, increase the group velocity but allow strong convective instabilities at high normalized frequencies well above Omega(sub He(+)). These waves are reflected in the magnetosphere and can exist for several equatorial transits without significant damping. They are left-handed polarized only on the first equatorial crossing and become linearly polarized for the remainder of the ray path. Consequently, these waves should be observed with basically linear polarization at all frequencies and all latitudes in the early morning local time sector. Wave growth below Omega(sub He(+)) is severely limited owing to the narrow bandwidth for instability and the small resonant path lengths. In the afternoon sector, where plasma densities can exceed 10(exp 7)/cu m, intense convective amplification is possible both above and below Omega(sub He(+)). Waves below Omega(sub He(+)) are not subject to reflection when the O(+) concentration is small and therefore should be observed with left-handed polarization near the equator and essentially linear polarization at higher latitudes. Since the He(+) concentration is usually large in the afternoon sector, guided mode waves above Omega(sub He(+)) reflect to form a background distribution with basically linear polarization. We suggest that the strong left-handed polarized emissions observed by AMPTE in the afternoon sector near the equator are probably due to strongly growing low group velocity waves at frequencies just below Omega(sub He(+)), and on the guided mode above Omega(sub He(+)).

First-Order System Least Squares for Velocity-Vorticity-Pressure Form of the Stokes Equations, with Application to Linear Elasticity

NASA Technical Reports Server (NTRS)

Cai, Zhiqiang; Manteuffel, Thomas A.; McCormick, Stephen F.

1996-01-01

In this paper, we study the least-squares method for the generalized Stokes equations (including linear elasticity) based on the velocity-vorticity-pressure formulation in d = 2 or 3 dimensions. The least squares functional is defined in terms of the sum of the L(exp 2)- and H(exp -1)-norms of the residual equations, which is weighted appropriately by by the Reynolds number. Our approach for establishing ellipticity of the functional does not use ADN theory, but is founded more on basic principles. We also analyze the case where the H(exp -1)-norm in the functional is replaced by a discrete functional to make the computation feasible. We show that the resulting algebraic equations can be uniformly preconditioned by well-known techniques.

Whistler and Alfvén Mode Cyclotron Masers in Space

NASA Astrophysics Data System (ADS)

Trakhtengerts, V. Y.; Rycroft, M. J.

2012-10-01

Preface; 1. Introduction; 2. Basic theory of cyclotron masers (CMs); 3. Linear theory of the cyclotron instability (CI); 4. Backward wave oscillator (BWO) regime in CMs; 5. Nonlinear cyclotron wave-particle interactions for a quasi-monochromatic wave; 6. Nonlinear interaction of quasi-monochromatic whistler mode waves with gyroresonant electrons in an in homogeneous plasma; 7. Wavelet amplification in an inhomogeneous plasma; 8. Quasi-linear theory of cyclotron masers; 9. Nonstationary generation regimes, and modulation effects; 10. ELF/VLF noise-like emissions and electrons in the Earth's radiation belts; 11. Generation of discrete ELF/VLF whistler mode emissions; 12. Cyclotron instability of the proton radiation belts; 13. Cyclotron masers elsewhere in the solar system and in laboratory plasma devices; Epilogue; Glossary of terms; List of acronyms; References; Index.

Design and Stability of an On-Orbit Attitude Control System Using Reaction Control Thrusters

NASA Technical Reports Server (NTRS)

Hall, Robert A.; Hough, Steven; Orphee, Carolina; Clements, Keith

2016-01-01

Basic principles for the design and stability of a spacecraft on-orbit attitude control system employing on-off Reaction Control System (RCS) thrusters are presented. Both vehicle dynamics and the control system actuators are inherently nonlinear, hence traditional linear control system design approaches are not directly applicable. This paper has two main aspects: It summarizes key RCS design principles from earlier NASA vehicles, notably the Space Shuttle and Space Station programs, and introduces advances in the linear modelling and analyses of a phase plane control system derived in the initial development of the NASA's next upper stage vehicle, the Exploration Upper Stage (EUS). Topics include thruster hardware specifications, phase plane design and stability, jet selection approaches, filter design metrics, and RCS rotational maneuver logic.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Quam, W.; Del Duca, T.; Plake, W.

This paper describes a pocket-calculator-sized, neutron-sensitive, REM-responding personnel dosimeter that uses three tissue-equivalent cylindrical proportional counters as neutron-sensitive detectors. These are conventionally called Linear Energy Transfer (LET) counters. Miniaturized hybrid circuits are used for the linear pulse handling electronics, followed by a 256-channel ADC. A CMOS microprocessor is used to calculate REM exposure from the basic rads-tissue data supplied by the LET counters and also to provide timing and display functions. The instrument is used to continuously accumulate time in hours since reset, total counts accumulated, rads-tissue, and REM. The user can display any one of these items or amore » channel number (an aid in calibration) at any time. Such data are provided with a precision of +- 3% for a total exposure of 1 mREM over eight hours.« less

Functional differentiability in time-dependent quantum mechanics.

PubMed

Penz, Markus; Ruggenthaler, Michael

2015-03-28

In this work, we investigate the functional differentiability of the time-dependent many-body wave function and of derived quantities with respect to time-dependent potentials. For properly chosen Banach spaces of potentials and wave functions, Fréchet differentiability is proven. From this follows an estimate for the difference of two solutions to the time-dependent Schrödinger equation that evolve under the influence of different potentials. Such results can be applied directly to the one-particle density and to bounded operators, and present a rigorous formulation of non-equilibrium linear-response theory where the usual Lehmann representation of the linear-response kernel is not valid. Further, the Fréchet differentiability of the wave function provides a new route towards proving basic properties of time-dependent density-functional theory.

Terahertz emission driven by two-color laser pulses at various frequency ratios

NASA Astrophysics Data System (ADS)

Wang, W.-M.; Sheng, Z.-M.; Li, Y.-T.; Zhang, Y.; Zhang, J.

2017-08-01

We present a simulation study of terahertz radiation from a gas driven by two-color laser pulses in a broad range of frequency ratios ω1/ω0 . Our particle-in-cell simulation results show that there are three series with ω1/ω0=2 n , n +1 /2 , n ±1 /3 (n is a positive integer) for high-efficiency and stable radiation generation. The radiation strength basically decreases with the increasing ω1 and scales linearly with the laser wavelength. These rules are broken when ω1/ω0<1 and much stronger radiation may be generated at any ω1/ω0 . These results can be explained with a model based on gas ionization by two linear-superposition laser fields, rather than a multiwave mixing model.

Electromembrane extraction using two separate cells: A new design for simultaneous extraction of acidic and basic compounds.

PubMed

Nojavan, Saeed; Asadi, Sakine

2016-02-01

Simultaneous extraction of acidic and basic analytes from a sample is seen to be a challenging task. In this work, a novel and efficient electromembrane extraction (EME) method based on two separate cells was applied to simultaneously extract and preconcentrate two acidic drugs (naproxen and ibuprofen) along with a basic drug (ketamine). Once both cells were filled with the sample solution, basic drug was extracted from one cell with the other cell used to extract acidic drugs. The employed supported liquid membranes for the extraction of acidic and basic drugs were 2-ethyl hexanol and 1-octanol, respectively. Under an applied potential of 250 V in the course of the extraction process, acidic, and basic drugs were extracted from a 3.0 mL aqueous sample solution into 25 μL acceptor solutions. The pH values of the donor and acceptor solutions in the cathodic cell were 5.0 and 1.5, respectively, the corresponding values in the anodic cell were, however, 8.0 and 12.5, respectively. The rates of recovery obtained within 20 min of extraction time at a stirring rate of 750 rpm ranged from 45 to 54%. With correlation coefficients ranging from 0.990 to 0.996, the proposed EME technique provided good linearity over a concentration range of 20-1000 ng/mL. The LOD for all drugs was found to be 6.7 ng/mL, while reproducibility ranged from 7 to 12% (n = 5). Finally, applying the proposed method to determine and quantify the drugs in urine and wastewater samples, satisfactory results were achieved. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sharma, V.K.; Patel, A.S.; Sharma, A.

This paper presents the design of magnetic coil for relativistic magnetron (RM) for LIA (Linear Induction Accelerator)-400 systems. Vacuum improves the efficiency of RM for HPM generation. Magnetic field in RM is very critical parameter and should be nearly constant in the active region. Typical coils are helical in nature, which have multi turns of varying radius. Magnetic field calculation of such coils with basic equations of Helmholtz coils or solenoid with mean radius can only give estimation. Field computational softwares like CST require small mesh size and boundary at very far so consume large memory and take very muchmore » time. Helical coils are simplified such that the basic law of magnetic field calculation i.e. Bio-Savart law can be applied with less complexity. Pairs of spiral coils have been analyzed for magnetic field and Lorenz's force. The approach is field experimentally validated. (author)« less

Evaluation of aerodynamic derivatives from a magnetic balance system

NASA Technical Reports Server (NTRS)

Raghunath, B. S.; Parker, H. M.

1972-01-01

The dynamic testing of a model in the University of Virginia cold magnetic balance wind-tunnel facility is expected to consist of measurements of the balance forces and moments, and the observation of the essentially six degree of freedom motion of the model. The aerodynamic derivatives of the model are to be evaluated from these observations. The basic feasibility of extracting aerodynamic information from the observation of a model which is executing transient, complex, multi-degree of freedom motion is demonstrated. It is considered significant that, though the problem treated here involves only linear aerodynamics, the methods used are capable of handling a very large class of aerodynamic nonlinearities. The basic considerations include the effect of noise in the data on the accuracy of the extracted information. Relationships between noise level and the accuracy of the evaluated aerodynamic derivatives are presented.

[Application of reversed-phase ion-pair chromatography for universal estimation of octanol-water partition coefficients of acid, basic and amphoteric drugs].

PubMed

Zhu, Hui; Yang, Ri-Fang; Yun, Liu-Hong; Jiang, Yu; Li, Jin

2009-09-01

This paper is to establish a reversed-phase ion-pair chromatography (RP-IPC) method for universal estimation of the octanol/water partition coefficients (logP) of a wide range of structurally diverse compounds including acidic, basic, neutral and amphoteric species. The retention factors corresponding to 100% water (logk(w)) were derived from the linear part of the logk'/phi relationship, using at least four isocratic logk' values containing different organic compositions. The logk(w) parameters obtained were close to the corresponding logP values obtained with the standard "shake flask" methods. The mean deviation for test drugs is 0.31. RP-IPC with trifluoroacetic acid as non classic ion-pair agents can be applicable to determine the logP values for a variety of drug-like molecules with increased accuracy.

Update on Bayesian Blocks: Segmented Models for Sequential Data

NASA Technical Reports Server (NTRS)

Scargle, Jeff

2017-01-01

The Bayesian Block algorithm, in wide use in astronomy and other areas, has been improved in several ways. The model for block shape has been generalized to include other than constant signal rate - e.g., linear, exponential, or other parametric models. In addition the computational efficiency has been improved, so that instead of O(N**2) the basic algorithm is O(N) in most cases. Other improvements in the theory and application of segmented representations will be described.

Linear and nonlinear aspects of the tropical 30-60 day oscillation: A modeling study

NASA Technical Reports Server (NTRS)

Stevens, Duane E.; Stephens, Graeme L.

1991-01-01

The scientific problem focused on study of the tropical 30-60 day oscillation and explanation for this phenomenon is discussed. The following subject areas are covered: the scientific problem (the importance of low frequency oscillations; suggested mechanisms for developing the tropical 30-60 day oscillation); proposed research and its objective; basic approach to research; and results (satellite data analysis and retrieval development; thermodynamic model of the oscillation; the 5-level GCM).

A survey of design methods for failure detection in dynamic systems

NASA Technical Reports Server (NTRS)

Willsky, A. S.

1975-01-01

A number of methods for detecting abrupt changes (such as failures) in stochastic dynamical systems are surveyed. The class of linear systems is concentrated on but the basic concepts, if not the detailed analyses, carry over to other classes of systems. The methods surveyed range from the design of specific failure-sensitive filters, to the use of statistical tests on filter innovations, to the development of jump process formulations. Tradeoffs in complexity versus performance are discussed.

Survey of beam instrumentation used in SLC

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ecklund, S.D.

A survey of beam instruments used at SLAC in the SLC machine is presented. The basic utility and operation of each device is briefly described. The various beam instruments used at the Stanford Linear Collider (SLC), can be classified by the function they perform. Beam intensity, position and size are typical of the parameters of beam which are measured. Each type of parameter is important for adjusting or tuning the machine in order to achieve optimum performance. 39 refs.

An exact solution to the relativistic equation of motion of a charged particle driven by a linearly polarized electromagnetic wave

NASA Technical Reports Server (NTRS)

Shebalin, John V.

1988-01-01

An exact analytic solution is found for a basic electromagnetic wave-charged particle interaction by solving the nonlinear equations of motion. The particle position, velocity, and corresponding time are found to be explicit functions of the total phase of the wave. Particle position and velocity are thus implicit functions of time. Applications include describing the motion of a free electron driven by an intense laser beam..

Double-Diffusive Convection in Rotational Shear

DTIC Science & Technology

2015-03-01

salt finger development is 0 and 0Z ZT S> > . The model uses the Boussinesq equations of motion with the linear equations of state, are expressed in...reference density from the Boussinesq approximation. ( )top bottom Z T T T H − = (2.2) The resultant non-dimensionalized equations for the model are...S T k k t = to determine how the system evolved during the simulation. B. VERSIONS OF THE BASIC MODEL This research was based on four separate

Discussion: Numerical study on the entrainment of bed material into rapid landslides

USGS Publications Warehouse

Iverson, Richard M.

2013-01-01

A paper recently published in this journal (Pirulli & Pastor, 2012) uses numerical modelling to study the important problem of entrainment of bed material by landslides. Unfortunately, some of the basic equations employed in the study are flawed, because they violate the principle of linear momentum conservation. Similar errors exist in some other studies of entrainment, and the errors appear to stem from confusion about the role of bed-sediment inertia in differing frames of reference.

The Educational Process in the Emerging Information Society: Conditions for the Reversal of the Linear Model of Education and the Development of an Open Type Hybrid Learning Environment.

ERIC Educational Resources Information Center

Anastasiades, Panagiotes S.; Retalis, Simos

The introduction of communications and information technologies in the area of education tends to create a totally different environment, which is marked by a change of the teacher's role and a transformation of the basic components that make up the meaning and content of the learning procedure as a whole. It could be said that, despite any…

[Approach to the Development of Mind and Persona].

PubMed

Sawaguchi, Toshiko

2018-01-01

To access medical specialists by health specialists working in the regional health field, the possibility of utilizing the voice approach for dissociative identity disorder (DID) patients as a health assessment for medical access (HAMA) was investigated. The first step is to investigate whether the plural personae in a single DID patient can be discriminated by voice analysis. Voices of DID patients including these with different personae were extracted from YouTube and were analysed using the software PRAAT with basic frequency, oral factors, chin factors and tongue factors. In addition, RAKUGO story teller voices made artificially and dramatically were analysed in the same manner. Quantitive and qualitative analysis method were carried out and nested logistic regression and a nested generalized linear model was developed. The voice from different personae in one DID patient could be visually and easily distinquished using basic frequency curve, cluster analysis and factor analysis. In the canonical analysis, only Roy's maximum root was <0.01. In the nested generalized linear model, the model using a standard deviation (SD) indicator fit best and some other possibilities are shown here. In DID patients, the short transition time among plural personae could guide to the risky situation such as suicide. So if the voice approach can show the time threshold of changes between the different personae, it would be useful as an Access Assessment in the form of a simple HAMA.

Eshelby's problem of polygonal inclusions with polynomial eigenstrains in an anisotropic magneto-electro-elastic full plane

PubMed Central

Lee, Y.-G.; Zou, W.-N.; Pan, E.

2015-01-01

This paper presents a closed-form solution for the arbitrary polygonal inclusion problem with polynomial eigenstrains of arbitrary order in an anisotropic magneto-electro-elastic full plane. The additional displacements or eigendisplacements, instead of the eigenstrains, are assumed to be a polynomial with general terms of order M+N. By virtue of the extended Stroh formulism, the induced fields are expressed in terms of a group of basic functions which involve boundary integrals of the inclusion domain. For the special case of polygonal inclusions, the boundary integrals are carried out explicitly, and their averages over the inclusion are also obtained. The induced fields under quadratic eigenstrains are mostly analysed in terms of figures and tables, as well as those under the linear and cubic eigenstrains. The connection between the present solution and the solution via the Green's function method is established and numerically verified. The singularity at the vertices of the arbitrary polygon is further analysed via the basic functions. The general solution and the numerical results for the constant, linear, quadratic and cubic eigenstrains presented in this paper enable us to investigate the features of the inclusion and inhomogeneity problem concerning polynomial eigenstrains in semiconductors and advanced composites, while the results can further serve as benchmarks for future analyses of Eshelby's inclusion problem. PMID:26345141

Ignition study of a petrol/CNG single cylinder engine

NASA Astrophysics Data System (ADS)

Khan, N.; Saleem, Z.; Mirza, A. A.

2005-11-01

Benefits of laser ignition over the electrical ignition system for Compressed Natural Gas (CNG) engines have fuelled automobile industry and led to an extensive research on basic characteristics to switch over to the emerging technologies. This study was undertaken to determine the electrical and physical characteristics of the electric spark ignition of single cylinder petrol/CNG engine to determine minimum ignition requirements and timeline of ignition events to use in subsequent laser ignition study. This communication briefly reviews the ongoing research activities and reports the results of this experimental study. The premixed petrol and CNG mixtures were tested for variation of current and voltage characteristics of the spark with speed of engine. The current magnitude of discharge circuit was found to vary linearly over a wide range of speed but the stroke to stroke fire time was found to vary nonlinearly. The DC voltage profiles were observed to fluctuate randomly during ignition process and staying constant in rest of the combustion cycle. Fire to fire peaks of current amplitudes fluctuated up to 10% of the peak values at constant speed but increased almost linearly with increase in speed. Technical barriers of laser ignition related to threshold minimum ignition energy, inter-pulse durations and firing sequence are discussed. Present findings provide a basic initiative and background information for designing suitable timeline algorithms for laser ignited leaner direct injected CNG engines.

Detector Outline Document for the Fourth Concept Detector ("4th") at the International Linear Collider

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barbareschi, Daniele; et al.

We describe a general purpose detector ( "Fourth Concept") at the International Linear Collider (ILC) that can measure with high precision all the fundamental fermions and bosons of the standard model, and thereby access all known physics processes. The 4th concept consists of four basic subsystems: a pixel vertex detector for high precision vertex definitions, impact parameter tagging and near-beam occupancy reduction; a Time Projection Chamber for robust pattern recognition augmented with three high-precision pad rows for precision momentum measurement; a high precision multiple-readout fiber calorimeter, complemented with an EM dual-readout crystal calorimeter, for the energy measurement of hadrons, jets,more » electrons, photons, missing momentum, and the tagging of muons; and, an iron-free dual-solenoid muon system for the inverse direction bending of muons in a gas volume to achieve high acceptance and good muon momentum resolution. The pixel vertex chamber, TPC and calorimeter are inside the solenoidal magnetic field. All four subsytems separately achieve the important scientific goal to be 2-to-10 times better than the already excellent LEP detectors, ALEPH, DELPHI, L3 and OPAL. All four basic subsystems contribute to the identification of standard model partons, some in unique ways, such that consequent physics studies are cogent. As an integrated detector concept, we achieve comprehensive physics capabilities that puts all conceivable physics at the ILC within reach.« less

On the Origins of the Linear Free Energy Relationships: Exploring the Nature of the Off-Diagonal Coupling Elements in SN2 Reactions

PubMed Central

Rosta, Edina; Warshel, Arieh

2012-01-01

Understanding the relationship between the adiabatic free energy profiles of chemical reactions and the underlining diabatic states is central to the description of chemical reactivity. The diabatic states form the theoretical basis of Linear Free Energy Relationships (LFERs) and thus play a major role in physical organic chemistry and related fields. However, the theoretical justification for some of the implicit LFER assumptions has not been fully established by quantum mechanical studies. This study follows our earlier works1,2 and uses the ab initio frozen density functional theory (FDFT) method3 to evaluate both the diabatic and adiabatic free energy surfaces and to determine the corresponding off-diagonal coupling matrix elements for a series of SN2 reactions. It is found that the off-diagonal coupling matrix elements are almost the same regardless of the nucleophile and the leaving group but change upon changing the central group. Furthermore, it is also found that the off diagonal elements are basically the same in gas phase and in solution, even when the solvent is explicitly included in the ab initio calculations. Furthermore, our study establishes that the FDFT diabatic profiles are parabolic to a good approximation thus providing a first principle support to the origin of LFER. These findings further support the basic approximation of the EVB treatment. PMID:23329895

Theoretical foundations of spatially-variant mathematical morphology part ii: gray-level images.

PubMed

Bouaynaya, Nidhal; Schonfeld, Dan

2008-05-01

In this paper, we develop a spatially-variant (SV) mathematical morphology theory for gray-level signals and images in the Euclidean space. The proposed theory preserves the geometrical concept of the structuring function, which provides the foundation of classical morphology and is essential in signal and image processing applications. We define the basic SV gray-level morphological operators (i.e., SV gray-level erosion, dilation, opening, and closing) and investigate their properties. We demonstrate the ubiquity of SV gray-level morphological systems by deriving a kernel representation for a large class of systems, called V-systems, in terms of the basic SV graylevel morphological operators. A V-system is defined to be a gray-level operator, which is invariant under gray-level (vertical) translations. Particular attention is focused on the class of SV flat gray-level operators. The kernel representation for increasing V-systems is a generalization of Maragos' kernel representation for increasing and translation-invariant function-processing systems. A representation of V-systems in terms of their kernel elements is established for increasing and upper-semi-continuous V-systems. This representation unifies a large class of spatially-variant linear and non-linear systems under the same mathematical framework. Finally, simulation results show the potential power of the general theory of gray-level spatially-variant mathematical morphology in several image analysis and computer vision applications.

Mode selection in swirling jet experiments: a linear stability analysis

NASA Astrophysics Data System (ADS)

Gallaire, François; Chomaz, Jean-Marc

2003-11-01

The primary goal of the study is to identify the selection mechanism responsible for the appearance of a double-helix structure in the pre-breakdown stage of so-called screened swirling jets for which the circulation vanishes away from the jet. The family of basic flows under consideration combines the azimuthal velocity profiles of Carton & McWilliams (1989) and the axial velocity profiles of Monkewitz (1988). This model satisfactorily represents the nozzle exit velocity distributions measured in the swirling jet experiment of Billant et al. (1998). Temporal and absolute/convective instability properties are directly retrieved from numerical simulations of the linear impulse response for different swirl parameter settings. A large range of negative helical modes, winding with the basic flow, are destabilized as swirl is increased, and their characteristics for large azimuthal wavenumbers are shown to agree with the asymptotic analysis of Leibovich & Stewartson (1983). However, the temporal study fails to yield a clear selection principle. The absolute/convective instability regions are mapped out in the plane of the external axial flow and swirl parameters. The absolutely unstable domain is enhanced by rotation and it remains open for arbitrarily large swirl. The swirling jet with zero external axial flow is found to first become absolutely unstable to a mode of azimuthal wavenumber m {=} {-}2, winding with the jet. It is suggested that this selection mechanism accounts for the experimental observation of a double-helix structure.

MO-F-16A-02: Simulation of a Medical Linear Accelerator for Teaching Purposes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carlone, M; Lamey, M; Anderson, R

Purpose: Detailed functioning of linear accelerator physics is well known. Less well developed is the basic understanding of how the adjustment of the linear accelerator's electrical components affects the resulting radiation beam. Other than the text by Karzmark, there is very little literature devoted to the practical understanding of linear accelerator functionality targeted at the radiotherapy clinic level. The purpose of this work is to describe a simulation environment for medical linear accelerators with the purpose of teaching linear accelerator physics. Methods: Varian type lineacs were simulated. Klystron saturation and peak output were modelled analytically. The energy gain of anmore » electron beam was modelled using load line expressions. The bending magnet was assumed to be a perfect solenoid whose pass through energy varied linearly with solenoid current. The dose rate calculated at depth in water was assumed to be a simple function of the target's beam current. The flattening filter was modelled as an attenuator with conical shape, and the time-averaged dose rate at a depth in water was determined by calculating kerma. Results: Fifteen analytical models were combined into a single model called SIMAC. Performance was verified systematically by adjusting typical linac control parameters. Increasing klystron pulse voltage increased dose rate to a peak, which then decreased as the beam energy was further increased due to the fixed pass through energy of the bending magnet. Increasing accelerator beam current leads to a higher dose per pulse. However, the energy of the electron beam decreases due to beam loading and so the dose rate eventually maximizes and the decreases as beam current was further increased. Conclusion: SIMAC can realistically simulate the functionality of a linear accelerator. It is expected to have value as a teaching tool for both medical physicists and linear accelerator service personnel.« less

Statistical power for the comparative regression discontinuity design with a nonequivalent comparison group.

PubMed

Tang, Yang; Cook, Thomas D; Kisbu-Sakarya, Yasemin

2018-03-01

In the "sharp" regression discontinuity design (RD), all units scoring on one side of a designated score on an assignment variable receive treatment, whereas those scoring on the other side become controls. Thus the continuous assignment variable and binary treatment indicator are measured on the same scale. Because each must be in the impact model, the resulting multi-collinearity reduces the efficiency of the RD design. However, untreated comparison data can be added along the assignment variable, and a comparative regression discontinuity design (CRD) is then created. When the untreated data come from a non-equivalent comparison group, we call this CRD-CG. Assuming linear functional forms, we show that power in CRD-CG is (a) greater than in basic RD; (b) less sensitive to the location of the cutoff and the distribution of the assignment variable; and that (c) fewer treated units are needed in the basic RD component within the CRD-CG so that savings can result from having fewer treated cases. The theory we develop is used to make numerical predictions about the efficiency of basic RD and CRD-CG relative to each other and to a randomized control trial. Data from the National Head Start Impact study are used to test these predictions. The obtained estimates are closer to the predicted parameters for CRD-CG than for basic RD and are generally quite close to the parameter predictions, supporting the emerging argument that CRD should be the design of choice in many applications for which basic RD is now used. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Disease invasion risk in a growing population.

PubMed

Yuan, Sanling; van den Driessche, P; Willeboordse, Frederick H; Shuai, Zhisheng; Ma, Junling

2016-09-01

The spread of an infectious disease may depend on the population size. For simplicity, classic epidemic models assume homogeneous mixing, usually standard incidence or mass action. For standard incidence, the contact rate between any pair of individuals is inversely proportional to the population size, and so the basic reproduction number (and thus the initial exponential growth rate of the disease) is independent of the population size. For mass action, this contact rate remains constant, predicting that the basic reproduction number increases linearly with the population size, meaning that disease invasion is easiest when the population is largest. In this paper, we show that neither of these may be true on a slowly evolving contact network: the basic reproduction number of a short epidemic can reach its maximum while the population is still growing. The basic reproduction number is proportional to the spectral radius of a contact matrix, which is shown numerically to be well approximated by the average excess degree of the contact network. We base our analysis on modeling the dynamics of the average excess degree of a random contact network with constant population input, proportional deaths, and preferential attachment for contacts brought in by incoming individuals (i.e., individuals with more contacts attract more incoming contacts). In addition, we show that our result also holds for uniform attachment of incoming contacts (i.e., every individual has the same chance of attracting incoming contacts), and much more general population dynamics. Our results show that a disease spreading in a growing population may evade control if disease control planning is based on the basic reproduction number at maximum population size.

A Diary Study of Basic Psychological Needs and Daily Headache Experience.

PubMed

Greene, Nathaniel R; Smith, C Veronica; Jewell, Devin E; Smitherman, Todd A

2018-04-01

A diary study was conducted to investigate the relationships between headache activity and basic psychological needs satisfaction. One hundred sixteen young adults (M age = 19.17 (SD = 2.90); 81.7% female; 75.9% Caucasian) completed an online daily diary of headache activity and needs satisfaction for 3 weeks. Data were analyzed using hierarchical linear modeling. On days when headache occurred, participants reported decreased needs satisfaction of competence (γ 10  = -0.18, P = .014) and relatedness (γ 10  = -0.24, P = .003), and a marginal but not significant reduction in autonomy (γ 10  = -0.13, P = .067). Additionally, more severe headaches were associated with decreased needs satisfaction in autonomy (γ 10  = -0.08, P = .009), competence (γ 10  = -0.08, P = .011), and relatedness (γ 10  = -0.09, P = .005). Presence of a headache diagnosis did not moderate the relationship between headache occurrence and basic needs satisfaction (all Ps ≥ .24). This preliminary study is the first to show that headache is related to reduced basic psychological needs satisfaction, providing a potential account for one mechanism by which headache may negatively affect quality of life. Further research is needed to extend these findings to larger samples of migraine sufferers to enable more thorough between-group comparisons of headache-related burden on basic needs satisfaction. These findings may be informative for treatment approaches that focus on outcomes beyond mere symptom reduction. © 2018 American Headache Society.

Charge heterogeneity: Basic antibody charge variants with increased binding to Fc receptors

PubMed Central

Hintersteiner, Beate; Lingg, Nico; Zhang, Peiqing; Woen, Susanto; Hoi, Kong Meng; Stranner, Stefan; Wiederkum, Susanne; Mutschlechner, Oliver; Schuster, Manfred; Loibner, Hans; Jungbauer, Alois

2016-01-01

ABSTRACT We identified active isoforms of the chimeric anti-GD2 antibody, ch14.18, a recombinant antibody produced in Chinese hamster ovary cells, which is already used in clinical trials.1,2,3 We separated the antibody by high resolution ion-exchange chromatography with linear pH gradient elution into acidic, main and basic charge variants on a preparative scale yielding enough material for an in-depth study of the sources and the effects of microheterogeneity. The binding affinity of the charge variants toward the antigen and various cell surface receptors was studied by Biacore. Effector functions were evaluated using cellular assays for antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity. Basic charge variants showed increased binding to cell surface receptor FcγRIIIa, which plays a major role in regulating effector functions. Furthermore, increased binding of the basic fractions to the neonatal receptor was observed. As this receptor mediates the prolonged half-life of IgG in human serum, this data may well hint at an increased serum half-life of these basic variants compared to their more acidic counterparts. Different glycoform patterns, C-terminal lysine clipping and N-terminal pyroglutamate formation were identified as the main structural sources for the observed isoform pattern. Potential differences in structural stability between individual charge variant fractions by nano differential scanning calorimetry could not been detected. Our in-vitro data suggests that the connection between microheterogeneity and the biological activity of recombinant antibody therapeutics deserves more attention than commonly accepted. PMID:27559765

Neuropsychological basic deficits in preschoolers at risk for ADHD: a meta-analysis.

PubMed

Pauli-Pott, Ursula; Becker, Katja

2011-06-01

Widely accepted neuropsychological theories on attention deficit hyperactivity disorder (ADHD) assume that the complex symptoms of the disease arise from developmentally preceding neuropsychological basic deficits. These deficits in executive functions and delay aversion are presumed to emerge in the preschool period. The corresponding normative developmental processes include phases of relative stability and rapid change. These non-linear developmental processes might have implications for concurrent and predictive associations between basic deficits and ADHD symptoms. To derive a description of the nature and strength of these associations, a meta-analysis was conducted. It is assumed that weighted mean effect sizes differ between basic deficits and depend on age. The meta-analysis included 25 articles (n=3005 children) in which associations between assessments of basic deficits (i.e. response inhibition, interference control, delay aversion, working memory, flexibility, and vigilance/arousal) in the preschool period and concurrent or subsequent ADHD symptoms or diagnosis of ADHD had been analyzed. For response inhibition and delay aversion, mean effect sizes were of medium to large magnitude while the mean effect size for working memory was small. Meta-regression analyses revealed that effect sizes of delay aversion tasks significantly decreased with increasing age while effect sizes of interference control tasks and Continuous Performance Tests (CPTs) significantly increased. Depending on the normative maturational course of each skill, time windows might exist that allow for a more or less valid assessment of a specific deficit. In future research these time windows might help to describe early developing forms of ADHD and to identify children at risk. Copyright © 2011 Elsevier Ltd. All rights reserved.

Auto-assembly of nanometer thick, water soluble layers of plasmid DNA complexed with diamines and basic amino acids on graphite: Greatest DNA protection is obtained with arginine.

PubMed

Khalil, T T; Boulanouar, O; Heintz, O; Fromm, M

2017-02-01

We have investigated the ability of diamines as well as basic amino acids to condense DNA onto highly ordered pyrolytic graphite with minimum damage after re-dissolution in water. Based on a bibliographic survey we briefly summarize DNA binding properties with diamines as compared to basic amino acids. Thus, solutions of DNA complexed with these linkers were drop-cast in order to deposit ultra-thin layers on the surface of HOPG in the absence or presence of Tris buffer. Atomic Force Microscopy analyses showed that, at a fixed ligand-DNA mixing ratio of 16, the mean thickness of the layers can be statistically predicted to lie in the range 0-50nm with a maximum standard deviation ±6nm, using a simple linear law depending on the DNA concentration. The morphology of the layers appears to be ligand-dependent. While the layers containing diamines present holes, those formed in the presence of basic amino acids, except for lysine, are much more compact and dense. X-ray Photoelectron Spectroscopy measurements provide compositional information indicating that, compared to the maximum number of DNA sites to which the ligands may bind, the basic amino acids Arg and His are present in large excess. Conservation of the supercoiled topology of the DNA plasmids was studied after recovery of the complex layers in water. Remarkably, arginine has the best protection capabilities whether Tris was present or not in the initial solution. Copyright © 2016 Elsevier B.V. All rights reserved.

Linear models for assessing mechanisms of sperm competition: the trouble with transformations.

PubMed

Eggert, Anne-Katrin; Reinhardt, Klaus; Sakaluk, Scott K

2003-01-01

Although sperm competition is a pervasive selective force shaping the reproductive tactics of males, the mechanisms underlying different patterns of sperm precedence remain obscure. Parker et al. (1990) developed a series of linear models designed to identify two of the more basic mechanisms: sperm lotteries and sperm displacement; the models can be tested experimentally by manipulating the relative numbers of sperm transferred by rival males and determining the paternity of offspring. Here we show that tests of the model derived for sperm lotteries can result in misleading inferences about the underlying mechanism of sperm precedence because the required inverse transformations may lead to a violation of fundamental assumptions of linear regression. We show that this problem can be remedied by reformulating the model using the actual numbers of offspring sired by each male, and log-transforming both sides of the resultant equation. Reassessment of data from a previous study (Sakaluk and Eggert 1996) using the corrected version of the model revealed that we should not have excluded a simple sperm lottery as a possible mechanism of sperm competition in decorated crickets, Gryllodes sigillatus.

Linear scan voltammetric indirect determination of Al(III) by the catalytic cathodic response of norepinephrine at the hanging mercury drop electrode.

PubMed

Zhang, Fuping; Ji, Ming; Xu, Quan; Yang, Li; Bi, Shuping

2005-09-01

The biological effects of aluminum (Al) have received much attention in recent years. Al is of basic relevance as concern with its reactivity and bioavailability. In this paper, the electrochemical behaviors of norepinephrine (NE) in the absence and presence of Al(III) at the hanging mercury drop electrode have been studied and applied to the practical analysis. Highly selective catalytic cathodic peak of NE is yielded by linear scan voltammetry (LSV) at -1.32 V (vs. SCE). A linear relationship holds between the cathodic peak current and the Al(III) concentration. It has been successfully applied to the determination of Al(III) in real waters and synthetic biological samples with satisfying results, which are in accordance with those obtained by ICP-AES method. The electrochemical properties and the mechanisms of the peaks in the presence and absence of Al(III) have been explored. The results show that they are irreversible adsorptive hydrogen catalytic waves. These studies not only enrich the methods of determining Al, but also lay foundations of further understanding of the mechanisms of neurodementia.

Amplitude-Phase Modulation, Topological Horseshoe and Scaling Attractor of a Dynamical System

NASA Astrophysics Data System (ADS)

Li, Chun-Lai; Li, Wen; Zhang, Jing; Xie, Yuan-Xi; Zhao, Yi-Bo

2016-09-01

A three-dimensional autonomous chaotic system is discussed in this paper. Some basic dynamical properties of the system, including phase portrait, Poincaré map, power spectrum, Kaplan-Yorke dimension, Lyapunov exponent spectra, signal amplitude and topological horseshoe are studied theoretically and numerically. The main finding by analysis is that the signal amplitude can be modulated via controlling the coefficients of the linear term, cross-product term and squared term simultaneously or respectively, and the phase of x3 can be modulated by the product of the coefficients of the linear term and cross-product term. Furthermore, scaling chaotic attractors of this system are achieved by modified projective synchronization with an optimization-based linear coupling method, which is safer for secure communications than the existed synchronization scheme since the scaling factors can be regarded as the security encoding key. Supported by Hunan Provincial Natural Science Foundation of China under Grant No. 2016JJ4036, University Natural Science Foundation of Jiangsu Province under Grant No. 14KJB120007 and the National Natural Science Foundation of China under Grant Nos. 11504176 and 11602084

Characterization of linear viscoelastic anti-vibration rubber mounts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lodhia, B.B.; Esat, I.I.

1996-11-01

The aim of this paper is to identify the dynamic characteristics that are evident in linear viscoelastic rubber mountings. The characteristics under consideration included the static and dynamic stiffnesses with the variation of amplitude and frequency of the sinusoidal excitation. Test samples of various rubber mix were tested and compared to reflect magnitude of dependency on composition. In the light of the results, the validity and effectiveness of a mathematical model was investigated and a suitable technique based on the Tschoegl and Emri Algorithm, was utilized to fit the model to the experimental data. The model which was chosen, wasmore » an extension of the basic Maxwell model, which is based on linear spring and dashpot elements in series and parallel called the Wiechert model. It was found that the extent to which the filler and vulcanisate was present in the rubber sample, did have a great effect on the static stiffness characteristics, and the storage and loss moduli. The Tschoegl and Emri Algorithm was successfully utilized in modelling the frequency response of the samples.« less

Error Analysis for RADAR Neighbor Matching Localization in Linear Logarithmic Strength Varying Wi-Fi Environment

PubMed Central

Tian, Zengshan; Xu, Kunjie; Yu, Xiang

2014-01-01

This paper studies the statistical errors for the fingerprint-based RADAR neighbor matching localization with the linearly calibrated reference points (RPs) in logarithmic received signal strength (RSS) varying Wi-Fi environment. To the best of our knowledge, little comprehensive analysis work has appeared on the error performance of neighbor matching localization with respect to the deployment of RPs. However, in order to achieve the efficient and reliable location-based services (LBSs) as well as the ubiquitous context-awareness in Wi-Fi environment, much attention has to be paid to the highly accurate and cost-efficient localization systems. To this end, the statistical errors by the widely used neighbor matching localization are significantly discussed in this paper to examine the inherent mathematical relations between the localization errors and the locations of RPs by using a basic linear logarithmic strength varying model. Furthermore, based on the mathematical demonstrations and some testing results, the closed-form solutions to the statistical errors by RADAR neighbor matching localization can be an effective tool to explore alternative deployment of fingerprint-based neighbor matching localization systems in the future. PMID:24683349

Error analysis for RADAR neighbor matching localization in linear logarithmic strength varying Wi-Fi environment.

PubMed

Zhou, Mu; Tian, Zengshan; Xu, Kunjie; Yu, Xiang; Wu, Haibo

2014-01-01

This paper studies the statistical errors for the fingerprint-based RADAR neighbor matching localization with the linearly calibrated reference points (RPs) in logarithmic received signal strength (RSS) varying Wi-Fi environment. To the best of our knowledge, little comprehensive analysis work has appeared on the error performance of neighbor matching localization with respect to the deployment of RPs. However, in order to achieve the efficient and reliable location-based services (LBSs) as well as the ubiquitous context-awareness in Wi-Fi environment, much attention has to be paid to the highly accurate and cost-efficient localization systems. To this end, the statistical errors by the widely used neighbor matching localization are significantly discussed in this paper to examine the inherent mathematical relations between the localization errors and the locations of RPs by using a basic linear logarithmic strength varying model. Furthermore, based on the mathematical demonstrations and some testing results, the closed-form solutions to the statistical errors by RADAR neighbor matching localization can be an effective tool to explore alternative deployment of fingerprint-based neighbor matching localization systems in the future.

Investigation of plasma behavior during noble gas injection in the end-cell of GAMMA 10/PDX by using the multi-fluid code ‘LINDA’

NASA Astrophysics Data System (ADS)

Islam, M. S.; Nakashima, Y.; Hatayama, A.

2017-12-01

The linear divertor analysis with fluid model (LINDA) code has been developed in order to simulate plasma behavior in the end-cell of linear fusion device GAMMA 10/PDX. This paper presents the basic structure and simulated results of the LINDA code. The atomic processes of hydrogen and impurities have been included in the present model in order to investigate energy loss processes and mechanism of plasma detachment. A comparison among Ar, Kr and Xe shows that Xe is the most effective gas on the reduction of electron and ion temperature. Xe injection leads to strong reduction in the temperature of electron and ion. The energy loss terms for both the electron and the ion are enhanced significantly during Xe injection. It is shown that the major energy loss channels for ion and electron are charge-exchange loss and radiative power loss of the radiator gas, respectively. These outcomes indicate that Xe injection in the plasma edge region is effective for reducing plasma energy and generating detached plasma in linear device GAMMA 10/PDX.

Cross Coating Weight Control by Electromagnetic Strip Stabilization at the Continuous Galvanizing Line of ArcelorMittal Florange

NASA Astrophysics Data System (ADS)

Guelton, Nicolas; Lopès, Catherine; Sordini, Henri

2016-08-01

In hot dip galvanizing lines, strip bending around the sink roll generates a flatness defect called crossbow. This defect affects the cross coating weight distribution by changing the knife-to-strip distance along the strip width and requires a significant increase in coating target to prevent any risk of undercoating. The already-existing coating weight control system succeeds in eliminating both average and skew coating errors but cannot do anything against crossbow coating errors. It has therefore been upgraded with a flatness correction function which takes advantage of the possibility of controlling the electromagnetic stabilizer. The basic principle is to split, for every gage scan, the coating weight cross profile of the top and bottom sides into two, respectively, linear and non-linear components. The linear component is used to correct the skew error by realigning the knives with the strip, while the non-linear component is used to distort the strip in the stabilizer in such a way that the strip is kept flat between the knives. Industrial evaluation is currently in progress but the first results have already shown that the strip can be significantly flattened between the knives and the production tolerances subsequently tightened without compromising quality.

Density-dependent host choice by disease vectors: epidemiological implications of the ideal free distribution.

PubMed

Basáñez, María-Gloria; Razali, Karina; Renz, Alfons; Kelly, David

2007-03-01

The proportion of vector blood meals taken on humans (the human blood index, h) appears as a squared term in classical expressions of the basic reproduction ratio (R(0)) for vector-borne infections. Consequently, R(0) varies non-linearly with h. Estimates of h, however, constitute mere snapshots of a parameter that is predicted, from evolutionary theory, to vary with vector and host abundance. We test this prediction using a population dynamics model of river blindness assuming that, before initiation of vector control or chemotherapy, recorded measures of vector density and human infection accurately represent endemic equilibrium. We obtain values of h that satisfy the condition that the effective reproduction ratio (R(e)) must equal 1 at equilibrium. Values of h thus obtained decrease with vector density, decrease with the vector:human ratio and make R(0) respond non-linearly rather than increase linearly with vector density. We conclude that if vectors are less able to obtain human blood meals as their density increases, antivectorial measures may not lead to proportional reductions in R(0) until very low vector levels are achieved. Density dependence in the contact rate of infectious diseases transmitted by insects may be an important non-linear process with implications for their epidemiology and control.

Realizing Broadband and Invertible Linear-to-circular Polarization Converter with Ultrathin Single-layer Metasurface

PubMed Central

Li, Zhancheng; Liu, Wenwei; Cheng, Hua; Chen, Shuqi; Tian, Jianguo

2015-01-01

The arbitrary control of the polarization states of light has attracted the interest of the scientific community because of the wide range of modern optical applications that such control can afford. However, conventional polarization control setups are bulky and very often operate only within a narrow wavelength range, thereby resisting optical system miniaturization and integration. Here, we present the basic theory, simulated demonstration, and in-depth analysis of a high-performance broadband and invertible linear-to-circular (LTC) polarization converter composed of a single-layer gold nanorod array with a total thickness of ~λ/70 for the near-infrared regime. This setup can transform a circularly polarized wave into a linearly polarized one or a linearly polarized wave with a wavelength-dependent electric field polarization angle into a circularly polarized one in the transmission mode. The broadband and invertible LTC polarization conversion can be attributed to the tailoring of the light interference at the subwavelength scale via the induction of the anisotropic optical resonance mode. This ultrathin single-layer metasurface relaxes the high-precision requirements of the structure parameters in general metasurfaces while retaining the polarization conversion performance. Our findings open up intriguing possibilities towards the realization of novel integrated metasurface-based photonics devices for polarization manipulation, modulation, and phase retardation. PMID:26667360

Dynamic stability of vortex solutions of Ginzburg-Landau and nonlinear Schrödinger equations

NASA Astrophysics Data System (ADS)

Weinstein, M. I.; Xin, J.

1996-10-01

The dynamic stability of vortex solutions to the Ginzburg-Landau and nonlinear Schrödinger equations is the basic assumption of the asymptotic particle plus field description of interacting vortices. For the Ginzburg-Landau dynamics we prove that all vortices are asymptotically nonlinearly stable relative to small radial perturbations. Initially finite energy perturbations of vortices decay to zero in L p (ℝ2) spaces with an algebraic rate as time tends to infinity. We also prove that under general (nonradial) perturbations, the plus and minus one-vortices are linearly dynamically stable in L 2; the linearized operator has spectrum equal to (-∞, 0] and generates a C 0 semigroup of contractions on L 2(ℝ2). The nature of the zero energy point is clarified; it is resonance, a property related to the infinite energy of planar vortices. Our results on the linearized operator are also used to show that the plus and minus one-vortices for the Schrödinger (Hamiltonian) dynamics are spectrally stable, i.e. the linearized operator about these vortices has ( L 2) spectrum equal to the imaginary axis. The key ingredients of our analysis are the Nash-Aronson estimates for obtaining Gaussian upper bounds for fundamental solutions of parabolic operator, and a combination of variational and maximum principles.

Quadratic Blind Linear Unmixing: A Graphical User Interface for Tissue Characterization

PubMed Central

Gutierrez-Navarro, O.; Campos-Delgado, D.U.; Arce-Santana, E. R.; Jo, Javier A.

2016-01-01

Spectral unmixing is the process of breaking down data from a sample into its basic components and their abundances. Previous work has been focused on blind unmixing of multi-spectral fluorescence lifetime imaging microscopy (m-FLIM) datasets under a linear mixture model and quadratic approximations. This method provides a fast linear decomposition and can work without a limitation in the maximum number of components or end-members. Hence this work presents an interactive software which implements our blind end-member and abundance extraction (BEAE) and quadratic blind linear unmixing (QBLU) algorithms in Matlab. The options and capabilities of our proposed software are described in detail. When the number of components is known, our software can estimate the constitutive end-members and their abundances. When no prior knowledge is available, the software can provide a completely blind solution to estimate the number of components, the end-members and their abundances. The characterization of three case studies validates the performance of the new software: ex-vivo human coronary arteries, human breast cancer cell samples, and in-vivo hamster oral mucosa. The software is freely available in a hosted webpage by one of the developing institutions, and allows the user a quick, easy-to-use and efficient tool for multi/hyper-spectral data decomposition. PMID:26589467

Quadratic blind linear unmixing: A graphical user interface for tissue characterization.

PubMed

Gutierrez-Navarro, O; Campos-Delgado, D U; Arce-Santana, E R; Jo, Javier A

2016-02-01

Spectral unmixing is the process of breaking down data from a sample into its basic components and their abundances. Previous work has been focused on blind unmixing of multi-spectral fluorescence lifetime imaging microscopy (m-FLIM) datasets under a linear mixture model and quadratic approximations. This method provides a fast linear decomposition and can work without a limitation in the maximum number of components or end-members. Hence this work presents an interactive software which implements our blind end-member and abundance extraction (BEAE) and quadratic blind linear unmixing (QBLU) algorithms in Matlab. The options and capabilities of our proposed software are described in detail. When the number of components is known, our software can estimate the constitutive end-members and their abundances. When no prior knowledge is available, the software can provide a completely blind solution to estimate the number of components, the end-members and their abundances. The characterization of three case studies validates the performance of the new software: ex-vivo human coronary arteries, human breast cancer cell samples, and in-vivo hamster oral mucosa. The software is freely available in a hosted webpage by one of the developing institutions, and allows the user a quick, easy-to-use and efficient tool for multi/hyper-spectral data decomposition. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Development of orientation tuning in simple cells of primary visual cortex

PubMed Central

Moore, Bartlett D.

2012-01-01

Orientation selectivity and its development are basic features of visual cortex. The original model of orientation selectivity proposes that elongated simple cell receptive fields are constructed from convergent input of an array of lateral geniculate nucleus neurons. However, orientation selectivity of simple cells in the visual cortex is generally greater than the linear contributions based on projections from spatial receptive field profiles. This implies that additional selectivity may arise from intracortical mechanisms. The hierarchical processing idea implies mainly linear connections, whereas cortical contributions are generally considered to be nonlinear. We have explored development of orientation selectivity in visual cortex with a focus on linear and nonlinear factors in a population of anesthetized 4-wk postnatal kittens and adult cats. Linear contributions are estimated from receptive field maps by which orientation tuning curves are generated and bandwidth is quantified. Nonlinear components are estimated as the magnitude of the power function relationship between responses measured from drifting sinusoidal gratings and those predicted from the spatial receptive field. Measured bandwidths for kittens are slightly larger than those in adults, whereas predicted bandwidths are substantially broader. These results suggest that relatively strong nonlinearities in early postnatal stages are substantially involved in the development of orientation tuning in visual cortex. PMID:22323631

The analysis of decimation and interpolation in the linear canonical transform domain.

PubMed

Xu, Shuiqing; Chai, Yi; Hu, Youqiang; Huang, Lei; Feng, Li

2016-01-01

Decimation and interpolation are the two basic building blocks in the multirate digital signal processing systems. As the linear canonical transform (LCT) has been shown to be a powerful tool for optics and signal processing, it is worthwhile and interesting to analyze the decimation and interpolation in the LCT domain. In this paper, the definition of equivalent filter in the LCT domain have been given at first. Then, by applying the definition, the direct implementation structure and polyphase networks for decimator and interpolator in the LCT domain have been proposed. Finally, the perfect reconstruction expressions for differential filters in the LCT domain have been presented as an application. The proposed theorems in this study are the bases for generalizations of the multirate signal processing in the LCT domain, which can advance the filter banks theorems in the LCT domain.

Differential Geometry and Lie Groups for Physicists

NASA Astrophysics Data System (ADS)

Fecko, Marián.

2006-10-01

Introduction; 1. The concept of a manifold; 2. Vector and tensor fields; 3. Mappings of tensors induced by mappings of manifolds; 4. Lie derivative; 5. Exterior algebra; 6. Differential calculus of forms; 7. Integral calculus of forms; 8. Particular cases and applications of Stoke's Theorem; 9. Poincaré Lemma and cohomologies; 10. Lie Groups - basic facts; 11. Differential geometry of Lie Groups; 12. Representations of Lie Groups and Lie Algebras; 13. Actions of Lie Groups and Lie Algebras on manifolds; 14. Hamiltonian mechanics and symplectic manifolds; 15. Parallel transport and linear connection on M; 16. Field theory and the language of forms; 17. Differential geometry on TM and T*M; 18. Hamiltonian and Lagrangian equations; 19. Linear connection and the frame bundle; 20. Connection on a principal G-bundle; 21. Gauge theories and connections; 22. Spinor fields and Dirac operator; Appendices; Bibliography; Index.

Differential Geometry and Lie Groups for Physicists

NASA Astrophysics Data System (ADS)

Fecko, Marián.

2011-03-01

Introduction; 1. The concept of a manifold; 2. Vector and tensor fields; 3. Mappings of tensors induced by mappings of manifolds; 4. Lie derivative; 5. Exterior algebra; 6. Differential calculus of forms; 7. Integral calculus of forms; 8. Particular cases and applications of Stoke's Theorem; 9. Poincaré Lemma and cohomologies; 10. Lie Groups - basic facts; 11. Differential geometry of Lie Groups; 12. Representations of Lie Groups and Lie Algebras; 13. Actions of Lie Groups and Lie Algebras on manifolds; 14. Hamiltonian mechanics and symplectic manifolds; 15. Parallel transport and linear connection on M; 16. Field theory and the language of forms; 17. Differential geometry on TM and T*M; 18. Hamiltonian and Lagrangian equations; 19. Linear connection and the frame bundle; 20. Connection on a principal G-bundle; 21. Gauge theories and connections; 22. Spinor fields and Dirac operator; Appendices; Bibliography; Index.

Dirac State in Giant Magnetoresistive Materials

NASA Astrophysics Data System (ADS)

Wu, Y.; Jo, N. H.; Ochi, M.; Huang, L.; Mou, D.; Kong, T.; Mun, E.; Wang, L.; Lee, Y.; Bud'Ko, S. L.; Canfield, P. C.; Trivedi, N.; Arito, R.; Kaminski, A.

We use ultrahigh resolution, tunable, vacuum ultraviolet laser-based angle-resolved photoemission spectroscopy (ARPES) to study the electronic properties of materials that recently were discovered to display titanic magnetoresistance. We find that that several of these materials have Dirac-like features in their band structure. In some materials those features are ``ordinary'' Dirac cones, while in others the linear Dirac dispersion of two crossing bands forms a linear object in 3D momentum space. Our observation poses an important question about the role of Dirac dispersion in the unusually high, non-saturating magnetoresistance of these materials. Research was supported by the US DOE, Office of Basic Energy Sciences under Contract No. DE-AC02-07CH11358; Gordon and Betty Moore Foundation EPiQS Initiative (Grant No. GBMF4411); CEM, a NSF MRSEC, under Grant No. DMR-1420451.

Study to investigate and evaluate means of optimizing the radar function for the space shuttle. [(pulse radar)

NASA Technical Reports Server (NTRS)

1975-01-01

Results are discussed of a study to define a radar and antenna system which best suits the space shuttle rendezvous requirements. Topics considered include antenna characteristics and antenna size tradeoffs, fundamental sources of measurement errors inherent in the target itself, backscattering crosssection models of the target and three basic candidate radar types. Antennas up to 1.5 meters in diameter are within specified installation constraints, however, a 1 meter diameter paraboloid and a folding, four slot backfeed on a two gimbal mount implemented for a spiral acquisition scan is recommended. The candidate radar types discussed are: (1) noncoherent pulse radar (2) coherent pulse radar and (3) pulse Doppler radar with linear FM ranging. The radar type recommended is a pulse Doppler with linear FM ranging. Block diagrams of each radar system are shown.

How to characterize the nonlinear amplifier?

NASA Technical Reports Server (NTRS)

Kallistratova, Dmitri Kouznetsov; Cotera, Carlos Flores

1994-01-01

The conception of the amplification of the coherent field is formulated. The definition of the coefficient of the amplification as the relation between the mean value of the field at the output to the value at the input and the definition of the noise as the difference between the number of photons in the output mode and square of the modulus of the mean value of the output amplitude are considered. Using a simple example it is shown that by these definitions the noise of the nonlinear amplifier may be less than the noise of the ideal linear amplifier of the same amplification coefficient. Proposals to search another definition of basic parameters of the nonlinear amplifiers are discussed. This definition should enable us to formulate the universal fundamental lower limit of the noise which should be valid for linear quantum amplifiers as for nonlinear ones.

Approximating the linear quadratic optimal control law for hereditary systems with delays in the control

NASA Technical Reports Server (NTRS)

Milman, Mark H.

1987-01-01

The fundamental control synthesis issue of establishing a priori convergence rates of approximation schemes for feedback controllers for a class of distributed parameter systems is addressed within the context of hereditary systems. Specifically, a factorization approach is presented for deriving approximations to the optimal feedback gains for the linear regulator-quadratic cost problem associated with time-varying functional differential equations with control delays. The approach is based on a discretization of the state penalty which leads to a simple structure for the feedback control law. General properties of the Volterra factors of Hilbert-Schmidt operators are then used to obtain convergence results for the controls, trajectories and feedback kernels. Two algorithms are derived from the basic approximation scheme, including a fast algorithm, in the time-invariant case. A numerical example is also considered.

Effect of curvature on stationary crossflow instability of a three-dimensional boundary layer

NASA Technical Reports Server (NTRS)

Lin, Ray-Sing; Reed, Helen L.

1993-01-01

An incompressible three-dimensional laminar boundary-layer flow over a swept wing is used as a model to study both the wall-curvature and streamline-curvature effects on the stationary crossflow instability. The basic state is obtained by solving the full Navier-Stokes (N-S) equations numerically. The linear disturbance equations are cast on a fixed, body-intrinsic, curvilinear coordinate system. Those nonparallel terms which contribute mainly to the streamline-curvature effect are retained in the formulation of the disturbance equations and approximated by their local finite difference values. The resulting eigenvalue problem is solved by a Chebyshev collocation method. The present results indicate that the convex wall curvature has a stabilizing effect, whereas the streamline curvature has a destabilizing effect. A validation of these effects with an N-S solution for the linear disturbance flow is provided.

Integrated approach to multimodal media content analysis

NASA Astrophysics Data System (ADS)

Zhang, Tong; Kuo, C.-C. Jay

1999-12-01

In this work, we present a system for the automatic segmentation, indexing and retrieval of audiovisual data based on the combination of audio, visual and textural content analysis. The video stream is demultiplexed into audio, image and caption components. Then, a semantic segmentation of the audio signal based on audio content analysis is conducted, and each segment is indexed as one of the basic audio types. The image sequence is segmented into shots based on visual information analysis, and keyframes are extracted from each shot. Meanwhile, keywords are detected from the closed caption. Index tables are designed for both linear and non-linear access to the video. It is shown by experiments that the proposed methods for multimodal media content analysis are effective. And that the integrated framework achieves satisfactory results for video information filtering and retrieval.

Improved importance sampling technique for efficient simulation of digital communication systems

NASA Technical Reports Server (NTRS)

Lu, Dingqing; Yao, Kung

1988-01-01

A new, improved importance sampling (IIS) approach to simulation is considered. Some basic concepts of IS are introduced, and detailed evolutions of simulation estimation variances for Monte Carlo (MC) and IS simulations are given. The general results obtained from these evolutions are applied to the specific previously known conventional importance sampling (CIS) technique and the new IIS technique. The derivation for a linear system with no signal random memory is considered in some detail. For the CIS technique, the optimum input scaling parameter is found, while for the IIS technique, the optimum translation parameter is found. The results are generalized to a linear system with memory and signals. Specific numerical and simulation results are given which show the advantages of CIS over MC and IIS over CIS for simulations of digital communications systems.

Approximating the linear quadratic optimal control law for hereditary systems with delays in the control

NASA Technical Reports Server (NTRS)

Milman, Mark H.

1988-01-01

The fundamental control synthesis issue of establishing a priori convergence rates of approximation schemes for feedback controllers for a class of distributed parameter systems is addressed within the context of hereditary schemes. Specifically, a factorization approach is presented for deriving approximations to the optimal feedback gains for the linear regulator-quadratic cost problem associated with time-varying functional differential equations with control delays. The approach is based on a discretization of the state penalty which leads to a simple structure for the feedback control law. General properties of the Volterra factors of Hilbert-Schmidt operators are then used to obtain convergence results for the controls, trajectories and feedback kernels. Two algorithms are derived from the basic approximation scheme, including a fast algorithm, in the time-invariant case. A numerical example is also considered.

Liquid Sloshing Dynamics

NASA Astrophysics Data System (ADS)

Ibrahim, Raouf A.

2005-06-01

The problem of liquid sloshing in moving or stationary containers remains of great concern to aerospace, civil, and nuclear engineers; physicists; designers of road tankers and ship tankers; and mathematicians. Beginning with the fundamentals of liquid sloshing theory, this book takes the reader systematically from basic theory to advanced analytical and experimental results in a self-contained and coherent format. The book is divided into four sections. Part I deals with the theory of linear liquid sloshing dynamics; Part II addresses the nonlinear theory of liquid sloshing dynamics, Faraday waves, and sloshing impacts; Part III presents the problem of linear and nonlinear interaction of liquid sloshing dynamics with elastic containers and supported structures; and Part IV considers the fluid dynamics in spinning containers and microgravity sloshing. This book will be invaluable to researchers and graduate students in mechanical and aeronautical engineering, designers of liquid containers, and applied mathematicians.

The high speed interconnect system architecture and operation

NASA Astrophysics Data System (ADS)

Anderson, Steven C.

The design and operation of a fiber-optic high-speed interconnect system (HSIS) being developed to meet the requirements of future avionics and flight-control hardware with distributed-system architectures are discussed. The HSIS is intended for 100-Mb/s operation of a local-area network with up to 256 stations. It comprises a bus transmission system (passive star couplers and linear media linked by active elements) and network interface units (NIUs). Each NIU is designed to perform the physical, data link, network, and transport functions defined by the ISO OSI Basic Reference Model (1982 and 1983) and incorporates a fiber-optic transceiver, a high-speed protocol based on the SAE AE-9B linear token-passing data bus (1986), and a specialized application interface unit. The operating modes and capabilities of HSIS are described in detail and illustrated with diagrams.

Phase-locked loops and their application

NASA Technical Reports Server (NTRS)

Lindsey, W. C. (Editor); Simon, M. K.

1978-01-01

A collection of papers is presented on the characteristics and capabilities of phase-locked loops (PLLs), along with some applications of interest. The discussion covers basic theory (linear and nonlinear); acquisition; threshold; stability; frequency demodulation and detection; tracking; cycle slipping and loss of lock; phase-locked oscillators; operation and performance in the presence of noise; AGC, AFC, and APC circuits and systems; digital PLL; and applications and miscellaneous. With the rapid development of IC technology, PLLs are expected to be used widely in consumer electronics.

A Basic Research for the Development and Evaluation of Novel MEMS Digital Accelerometers

DTIC Science & Technology

2013-02-01

that timing differences as measured by the circuit are linearly dependent on the measured capacitance changes. As such, the circuit’s readout is...error in the electronic measurement to refine the technique. An additional capability of the circuit is the ability to observe the impact of cold...low resistivity on (ɘ.01 Ω-cm) silicon on insulator wafers (SOI). The beams are fabricated in a 0.3 cm by 0.3 cm die which is then packaged and wire

A survey of design methods for failure detection in dynamic systems

NASA Technical Reports Server (NTRS)

Willsky, A. S.

1975-01-01

A number of methods for the detection of abrupt changes (such as failures) in stochastic dynamical systems were surveyed. The class of linear systems were emphasized, but the basic concepts, if not the detailed analyses, carry over to other classes of systems. The methods surveyed range from the design of specific failure-sensitive filters, to the use of statistical tests on filter innovations, to the development of jump process formulations. Tradeoffs in complexity versus performance are discussed.

Hybrid finite element and Brownian dynamics method for diffusion-controlled reactions.

PubMed

Bauler, Patricia; Huber, Gary A; McCammon, J Andrew

2012-04-28

Diffusion is often the rate determining step in many biological processes. Currently, the two main computational methods for studying diffusion are stochastic methods, such as Brownian dynamics, and continuum methods, such as the finite element method. This paper proposes a new hybrid diffusion method that couples the strengths of each of these two methods. The method is derived for a general multidimensional system, and is presented using a basic test case for 1D linear and radially symmetric diffusion systems.

Dynamics of flexible fibers and vesicles in Poiseuille flow at low Reynolds number.

PubMed

Farutin, Alexander; Piasecki, Tomasz; Słowicka, Agnieszka M; Misbah, Chaouqi; Wajnryb, Eligiusz; Ekiel-Jeżewska, Maria L

2016-09-21

The dynamics of flexible fibers and vesicles in unbounded planar Poiseuille flow at low Reynolds number is shown to exhibit similar basic features, when their equilibrium (moderate) aspect ratio is the same and vesicle viscosity contrast is relatively high. Tumbling, lateral migration, accumulation and shape evolution of these two types of flexible objects are analyzed numerically. The linear dependence of the accumulation position on relative bending rigidity, and other universal scalings are derived from the local shear flow approximation.

Algorithm Estimates Microwave Water-Vapor Delay

NASA Technical Reports Server (NTRS)

Robinson, Steven E.

1989-01-01

Accuracy equals or exceeds conventional linear algorithms. "Profile" algorithm improved algorithm using water-vapor-radiometer data to produce estimates of microwave delays caused by water vapor in troposphere. Does not require site-specific and weather-dependent empirical parameters other than standard meteorological data, latitude, and altitude for use in conjunction with published standard atmospheric data. Basic premise of profile algorithm, wet-path delay approximated closely by solution to simplified version of nonlinear delay problem and generated numerically from each radiometer observation and simultaneous meteorological data.

Recent developments in chaotic dynamics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ott, E.

1994-02-01

Before the relatively recent wide acceptance of the existence of chaotic dynamics, many physicists and engineers were under the impression that simple systems could necessarily only display simple solutions. This feeling had been unintentionally reinforced by conventional college courses which emphasize linear dynamics (partly because that is the only case with nice general solutions). More recently, physical experiments and numerical examples have abundantly demonstrated how wrong this feeling is. A brief review of chaotic dynamics is presented. Topics discussed include basic concepts, recent developments, and applications.

On the stability of an infinite swept attachment line boundary layer

NASA Technical Reports Server (NTRS)

Hall, P.; Mallik, M. R.; Poll, D. I. A.

1984-01-01

The instability of an infinite swept attachment line boundary layer is considered in the linear regime. The basic three dimensional flow is shown to be susceptible to travelling wave disturbances which propagate along the attachment line. The effect of suction on the instability is discussed and the results suggest that the attachment line boundary layer on a swept wing can be significantly stabilized by extremely small amounts of suction. The results obtained are in excellent agreement with the available experimental observations.

SLAC All Access: FACET

ScienceCinema

Hogan, Mark

2018-02-13

SLAC's Facility for Advanced Accelerator Experimental Tests, or FACET, is a test-bed where researchers are developing the technologies required for particle accelerators of the future. Scientists from all over the world come to explore ways of improving the power and efficiency of the particle accelerators used in basic research, medicine, industry and other areas important to society. In this video, Mark Hogan, head of SLAC's Advanced Accelerator Research Department, offers a glimpse into FACET, which uses part of SLAC's historic two-mile-long linear accelerator.

The Integration of Research in Judgment and Decision Theory

DTIC Science & Technology

1980-07-01

off at any one of a series of choice points in a basically linear, unidimensional, all-or-none series of relays is at least in part the result of the...Subjective and objective referents. An objective referent requires a series of observations in which inter-observer reliabilities approximate unity; as... series of studies by Br6hmer (1980). More generally, research as far back as that of Krechevsky’s in the 1930s was conducted precisely to show that

The Solution Construction of Heterotic Super-Liouville Model

NASA Astrophysics Data System (ADS)

Yang, Zhan-Ying; Zhen, Yi

2001-12-01

We investigate the heterotic super-Liouville model on the base of the basic Lie super-algebra Osp(1|2).Using the super extension of Leznov-Saveliev analysis and Drinfeld-Sokolov linear system, we construct the explicit solution of the heterotic super-Liouville system in component form. We also show that the solutions are local and periodic by calculating the exchange relation of the solution. Finally starting from the action of heterotic super-Liouville model, we obtain the conserved current and conserved charge which possessed the BRST properties.

Prediction of bead area contact load at the tire-wheel interface using NASTRAN

NASA Technical Reports Server (NTRS)

Chen, C. H. S.

1982-01-01

The theoretical prediction of the bead area contact load at the tire wheel interface using NASTRAN is reported. The application of the linear code to a basically nonlinear problem results in excessive deformation of the structure and the tire-wheel contact conditions become impossible to achieve. A psuedo-nonlinear approach was adopted in which the moduli of the cord reinforced composite are increased so that the computed key deformations matched that of the experiment. Numerical results presented are discussed.

An introduction to g methods.

PubMed

Naimi, Ashley I; Cole, Stephen R; Kennedy, Edward H

2017-04-01

Robins' generalized methods (g methods) provide consistent estimates of contrasts (e.g. differences, ratios) of potential outcomes under a less restrictive set of identification conditions than do standard regression methods (e.g. linear, logistic, Cox regression). Uptake of g methods by epidemiologists has been hampered by limitations in understanding both conceptual and technical details. We present a simple worked example that illustrates basic concepts, while minimizing technical complications. © The Author 2016; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.

Numerical solution of linear and nonlinear Fredholm integral equations by using weighted mean-value theorem.

PubMed

Altürk, Ahmet

2016-01-01

Mean value theorems for both derivatives and integrals are very useful tools in mathematics. They can be used to obtain very important inequalities and to prove basic theorems of mathematical analysis. In this article, a semi-analytical method that is based on weighted mean-value theorem for obtaining solutions for a wide class of Fredholm integral equations of the second kind is introduced. Illustrative examples are provided to show the significant advantage of the proposed method over some existing techniques.

Digital signal processing and control and estimation theory -- Points of tangency, area of intersection, and parallel directions

NASA Technical Reports Server (NTRS)

Willsky, A. S.

1976-01-01

A number of current research directions in the fields of digital signal processing and modern control and estimation theory were studied. Topics such as stability theory, linear prediction and parameter identification, system analysis and implementation, two-dimensional filtering, decentralized control and estimation, image processing, and nonlinear system theory were examined in order to uncover some of the basic similarities and differences in the goals, techniques, and philosophy of the two disciplines. An extensive bibliography is included.

A Quantum Groups Primer

NASA Astrophysics Data System (ADS)

Majid, Shahn

2002-05-01

Here is a self-contained introduction to quantum groups as algebraic objects. Based on the author's lecture notes for the Part III pure mathematics course at Cambridge University, the book is suitable as a primary text for graduate courses in quantum groups or supplementary reading for modern courses in advanced algebra. The material assumes knowledge of basic and linear algebra. Some familiarity with semisimple Lie algebras would also be helpful. The volume is a primer for mathematicians but it will also be useful for mathematical physicists.