The atomic orbitals of the topological atom.
Ramos-Cordoba, Eloy; Salvador, Pedro; Mayer, István
2013-06-01
The effective atomic orbitals have been realized in the framework of Bader's atoms in molecules theory for a general wavefunction. This formalism can be used to retrieve from any type of calculation a proper set of orthonormalized numerical atomic orbitals, with occupation numbers that sum up to the respective Quantum Theory of Atoms in Molecules (QTAIM) atomic populations. Experience shows that only a limited number of effective atomic orbitals exhibit significant occupation numbers. These correspond to atomic hybrids that closely resemble the core and valence shells of the atom. The occupation numbers of the remaining effective orbitals are almost negligible, except for atoms with hypervalent character. In addition, the molecular orbitals of a calculation can be exactly expressed as a linear combination of this orthonormalized set of numerical atomic orbitals, and the Mulliken population analysis carried out on this basis set exactly reproduces the original QTAIM atomic populations of the atoms. Approximate expansion of the molecular orbitals over a much reduced set of orthogonal atomic basis functions can also be accomplished to a very good accuracy with a singular value decomposition procedure.
ERIC Educational Resources Information Center
Bridgeman, Adam J.; Schmidt, Timothy W.; Young, Nigel A.
2013-01-01
The stretching modes of ML[subscript "x"] complexes have the same symmetry as the atomic orbitals on M that are used to form its s bonds. In the exercise suggested here, the atomic orbitals are used to derive the form of the stretching modes without the need for formal group theory. The analogy allows students to help understand many…
Electronic structure interpolation via atomic orbitals.
Chen, Mohan; Guo, G-C; He, Lixin
2011-08-17
We present an efficient scheme for accurate electronic structure interpolation based on systematically improvable optimized atomic orbitals. The atomic orbitals are generated by minimizing the spillage value between the atomic basis calculations and the converged plane wave basis calculations on some coarse k-point grid. They are then used to calculate the band structure of the full Brillouin zone using the linear combination of atomic orbitals algorithms. We find that usually 16-25 orbitals per atom can give an accuracy of about 10 meV compared to the full ab initio calculations, and the accuracy can be systematically improved by using more atomic orbitals. The scheme is easy to implement and robust, and works equally well for metallic systems and systems with complicated band structures. Furthermore, the atomic orbitals have much better transferability than Shirley's basis and Wannier functions, which is very useful for perturbation calculations.
Is It Time to Retire the Hybrid Atomic Orbital?
ERIC Educational Resources Information Center
Grushow, Alexander
2011-01-01
A rationale for the removal of the hybrid atomic orbital from the chemistry curriculum is examined. Although the hybrid atomic orbital model does not accurately predict spectroscopic energies, many chemical educators continue to use and teach the model despite the confusion it can cause for students. Three arguments for retaining the model in the…
NASA Astrophysics Data System (ADS)
Song, Chenchen; Martínez, Todd J.
2016-05-01
We present a tensor hypercontracted (THC) scaled opposite spin second order Møller-Plesset perturbation theory (SOS-MP2) method. By using THC, we reduce the formal scaling of SOS-MP2 with respect to molecular size from quartic to cubic. We achieve further efficiency by exploiting sparsity in the atomic orbitals and using graphical processing units (GPUs) to accelerate integral construction and matrix multiplication. The practical scaling of GPU-accelerated atomic orbital-based THC-SOS-MP2 calculations is found to be N2.6 for reference data sets of water clusters and alanine polypeptides containing up to 1600 basis functions. The errors in correlation energy with respect to density-fitting-SOS-MP2 are less than 0.5 kcal/mol for all systems tested (up to 162 atoms).
Song, Chenchen; Martínez, Todd J
2016-05-01
We present a tensor hypercontracted (THC) scaled opposite spin second order Møller-Plesset perturbation theory (SOS-MP2) method. By using THC, we reduce the formal scaling of SOS-MP2 with respect to molecular size from quartic to cubic. We achieve further efficiency by exploiting sparsity in the atomic orbitals and using graphical processing units (GPUs) to accelerate integral construction and matrix multiplication. The practical scaling of GPU-accelerated atomic orbital-based THC-SOS-MP2 calculations is found to be N(2.6) for reference data sets of water clusters and alanine polypeptides containing up to 1600 basis functions. The errors in correlation energy with respect to density-fitting-SOS-MP2 are less than 0.5 kcal/mol for all systems tested (up to 162 atoms).
Localized atomic orbitals for atoms in molecules. III. Polyatomic molecules
NASA Astrophysics Data System (ADS)
Aufderheide, Keith H.; Chung-Phillips, Alice
1982-02-01
Using a previously described method, localized atomic orbitals (LAOs) for atoms in molecules are constructed for the atoms C, N, O, and F in the polyatomic molecules CH4, NH3, OH2, CH3CH3, CH3NH2, CH3OH, CH3F, CH2CH2, C6H6, CO2, and CHCH. As in our prior studies, LAOs partition into sets of core, lone pair, and bonding orbitals. Ordinarily, both core and lone pair LAOs are doubly occupied and bonding is described principally as the interaction of bonding LAOs on adjacent, bonded atoms. Angles between valence LAOs on a given atom continue to vary in a manner reminiscent of trends common to simple valence shell electron pair repulsion theory. Of special interest are the systems CO2, C6H6, and CH3F: The peculiarities germane to these molecules are discussed fully in the text. Finally, certain properties (orbital populations, intra-atomic orbital angles, etc.) of groups (-CH3, -NH2, -OH, etc.) common to several systems studied show a remarkable transferability.
Antihydrogen-hydrogen elastic scattering at thermal energies using an atomic-orbital technique
Sinha, Prabal K.; Chaudhuri, Puspitapallab; Ghosh, A.S.
2003-05-01
In view of the recent interest in the trapping of antihydrogen atom H(bar sign), at very low temperatures, H-bar-H scattering has been investigated at low incident energies using a close-coupling model with the basis set H-bar(1s,2s,2p-bar)+H(1s,2s,2p-bar). The predicted s-wave elastic phase shifts, scattering length, and effective range are in a good agreement with the other recent predictions of Jonsell et al. and of Armour and Chamberlain. The results indicate that the atomic orbital expansion model is suitable to study the H-bar-H scattering at ultracold temperatures.
ERIC Educational Resources Information Center
Tsaparlis, Georgios
1997-01-01
Investigates the impact an undergraduate quantum chemistry course has on students' knowledge and understanding of atomic orbitals, molecular orbitals, and related concepts. Analysis reveals that students do not have a clear understanding of these concepts and confuse the various atomic orbital representations. Includes some suggestions and…
ERIC Educational Resources Information Center
Saputra, Andrian; Canaval, Lorentz R.; Sunyono; Fadiawati, Noor; Diawati, Chansyanah; Setyorini, M.; Kadaritna, Nina; Kadaryanto, Budi
2015-01-01
Quick and real-time plotting equations using the Winplot software can be employed to create accurate hybrid atomic orbitals without complicated scripting. Performing this task on their own, students can more easily understand and remember hybrid atomic orbitals, in terms of shape and orientation.
Igenbergs, Katharina; Wallerberger, Markus; Schweinzer, Josef; Aumayr, Friedrich
2012-05-25
The atomic-orbital close-coupling formalism is a well-known method for the semiclassical treatment of ion-atom collisions. Cross sections for these kinds of collisions are mainly needed in the analysis of certain spectroscopic data from nuclear fusion experiments as well as astrophysical data. We shall outline how the computational implementation can be improved in such a way that collisions involving heavy, highly charged impurity ions, such as Ar{sup 18+} can be treated. Furthermore we show and discuss exemplary results.
ERIC Educational Resources Information Center
Liguori, Lucia
2014-01-01
Atomic orbital theory is a difficult subject for many high school and beginning undergraduate students, as it includes mathematical concepts not yet covered in the school curriculum. Moreover, it requires certain ability for abstraction and imagination. A new atomic orbital model "the chocolate shop" created "by" students…
Helmich-Paris, Benjamin; Repisky, Michal; Visscher, Lucas
2016-07-01
We present a formulation of Laplace-transformed atomic orbital-based second-order Møller-Plesset perturbation theory (MP2) energies for two-component Hamiltonians in the Kramers-restricted formalism. This low-order scaling technique can be used to enable correlated relativistic calculations for large molecular systems. We show that the working equations to compute the relativistic MP2 energy differ by merely a change of algebra (quaternion instead of real) from their non-relativistic counterparts. With a proof-of-principle implementation we study the effect of the nuclear charge on the magnitude of half-transformed integrals and show that for light elements spin-free and spin-orbit MP2 energies are almost identical. Furthermore, we investigate the effect of separation of charge distributions on the Coulomb and exchange energy contributions, which show the same long-range decay with the inter-electronic/atomic distance as for non-relativistic MP2. A linearly scaling implementation is possible if the proper distance behavior is introduced to the quaternion Schwarz-type estimates as for non-relativistic MP2.
Helmich-Paris, Benjamin; Repisky, Michal; Visscher, Lucas
2016-07-01
We present a formulation of Laplace-transformed atomic orbital-based second-order Møller-Plesset perturbation theory (MP2) energies for two-component Hamiltonians in the Kramers-restricted formalism. This low-order scaling technique can be used to enable correlated relativistic calculations for large molecular systems. We show that the working equations to compute the relativistic MP2 energy differ by merely a change of algebra (quaternion instead of real) from their non-relativistic counterparts. With a proof-of-principle implementation we study the effect of the nuclear charge on the magnitude of half-transformed integrals and show that for light elements spin-free and spin-orbit MP2 energies are almost identical. Furthermore, we investigate the effect of separation of charge distributions on the Coulomb and exchange energy contributions, which show the same long-range decay with the inter-electronic/atomic distance as for non-relativistic MP2. A linearly scaling implementation is possible if the proper distance behavior is introduced to the quaternion Schwarz-type estimates as for non-relativistic MP2. PMID:27394099
NASA Astrophysics Data System (ADS)
Helmich-Paris, Benjamin; Repisky, Michal; Visscher, Lucas
2016-07-01
We present a formulation of Laplace-transformed atomic orbital-based second-order Møller-Plesset perturbation theory (MP2) energies for two-component Hamiltonians in the Kramers-restricted formalism. This low-order scaling technique can be used to enable correlated relativistic calculations for large molecular systems. We show that the working equations to compute the relativistic MP2 energy differ by merely a change of algebra (quaternion instead of real) from their non-relativistic counterparts. With a proof-of-principle implementation we study the effect of the nuclear charge on the magnitude of half-transformed integrals and show that for light elements spin-free and spin-orbit MP2 energies are almost identical. Furthermore, we investigate the effect of separation of charge distributions on the Coulomb and exchange energy contributions, which show the same long-range decay with the inter-electronic/atomic distance as for non-relativistic MP2. A linearly scaling implementation is possible if the proper distance behavior is introduced to the quaternion Schwarz-type estimates as for non-relativistic MP2.
Goings, Joshua J; Li, Xiaosong
2016-06-21
One of the challenges of interpreting electronic circular dichroism (ECD) band spectra is that different states may have different rotatory strength signs, determined by their absolute configuration. If the states are closely spaced and opposite in sign, observed transitions may be washed out by nearby states, unlike absorption spectra where transitions are always positive additive. To accurately compute ECD bands, it is necessary to compute a large number of excited states, which may be prohibitively costly if one uses the linear-response time-dependent density functional theory (TDDFT) framework. Here we implement a real-time, atomic-orbital based TDDFT method for computing the entire ECD spectrum simultaneously. The method is advantageous for large systems with a high density of states. In contrast to previous implementations based on real-space grids, the method is variational, independent of nuclear orientation, and does not rely on pseudopotential approximations, making it suitable for computation of chiroptical properties well into the X-ray regime.
NASA Astrophysics Data System (ADS)
Goings, Joshua J.; Li, Xiaosong
2016-06-01
One of the challenges of interpreting electronic circular dichroism (ECD) band spectra is that different states may have different rotatory strength signs, determined by their absolute configuration. If the states are closely spaced and opposite in sign, observed transitions may be washed out by nearby states, unlike absorption spectra where transitions are always positive additive. To accurately compute ECD bands, it is necessary to compute a large number of excited states, which may be prohibitively costly if one uses the linear-response time-dependent density functional theory (TDDFT) framework. Here we implement a real-time, atomic-orbital based TDDFT method for computing the entire ECD spectrum simultaneously. The method is advantageous for large systems with a high density of states. In contrast to previous implementations based on real-space grids, the method is variational, independent of nuclear orientation, and does not rely on pseudopotential approximations, making it suitable for computation of chiroptical properties well into the X-ray regime.
Kjærgaard, Thomas; Jørgensen, Poul; Thorvaldsen, Andreas J; Sałek, Paweł; Coriani, Sonia
2009-08-11
A Lagrangian approach has been used to derive gauge-origin independent expressions for two properties that rationalize magneto-optical activity, namely the Verdet constant V(ω) of the Faraday effect and the ℬ term of magnetic circular dichroism. The approach is expressed in terms of an atomic-orbital density-matrix based formulation of response theory and use London atomic orbitals to parametrize the magnetic field dependence. It yields a computational procedure which is both gauge-origin independent and suitable for linear-scaling at the level of time-dependent Hartree-Fock and density functional theory. The formulation includes a modified preconditioned conjugated gradient algorithm, which projects out the excited state component from the solution to the linear response equation. This is required when solving one of the response equations for the determination of the ℬ term and divergence is encountered if this component is not projected out. Illustrative results are reported for the Verdet constant of H2, HF, CO, N2O, and CH3CH2CH3 and for the ℬ term of pyrimidine, phosphabenzene, and pyridine. The results are benchmarked against gauge-origin independent CCSD values. PMID:26613143
Li, Hao; Chernyak, Vladimir Y; Tretiak, Sergei
2012-12-20
The exciton scattering (ES) method allows efficient calculations of spectroscopic observables in large low-dimensional conjugated molecular systems. To compute the transition dipoles between the ground and excited electronic states, we should extract the ES dipole parameters from quantum chemistry calculations in simple molecular fragments. In this manuscript, we show how to retrieve these parameters from any reference quantum chemistry model that uses an arbitrary nonorthogonal and possibly overcomplete atomic orbital basis set. Our approach relies on the natural atomic orbital (NAO) representation, in which the basis functions are orthonormal and the atom-like character is preserved. We apply the ES approach, combined with the NAO analysis to optical spectra of branched phenylacetylene oligomers. Absorption spectra predicted by the ES method demonstrate close agreement with the results of direct quantum chemistry calculations, when the Time-Dependent Density Functional Theory (TD-DFT) being used as a reference. This testifies applicability of a variety of quantum-chemical techniques, where the NAO population analysis can be conducted, for the ES framework. PMID:26291103
Li, Hao; Chernyak, Vladimir Y; Tretiak, Sergei
2012-12-20
The exciton scattering (ES) method allows efficient calculations of spectroscopic observables in large low-dimensional conjugated molecular systems. To compute the transition dipoles between the ground and excited electronic states, we should extract the ES dipole parameters from quantum chemistry calculations in simple molecular fragments. In this manuscript, we show how to retrieve these parameters from any reference quantum chemistry model that uses an arbitrary nonorthogonal and possibly overcomplete atomic orbital basis set. Our approach relies on the natural atomic orbital (NAO) representation, in which the basis functions are orthonormal and the atom-like character is preserved. We apply the ES approach, combined with the NAO analysis to optical spectra of branched phenylacetylene oligomers. Absorption spectra predicted by the ES method demonstrate close agreement with the results of direct quantum chemistry calculations, when the Time-Dependent Density Functional Theory (TD-DFT) being used as a reference. This testifies applicability of a variety of quantum-chemical techniques, where the NAO population analysis can be conducted, for the ES framework.
New Display-type Analyzer for Three-dimensional Fermi Surface Mapping and Atomic Orbital Analysis
Takahashi, Nobuaki; Matsuda, Hiroyuki; Shigenai, Shin; Hirama, Yoshiteru; Matsui, Fumihiko; Hamada, Yoji; Nakanishi, Koji; Namba, Hidetoshi; Kitamura, Toshiro; Soejima, Hiroyoshi; Daimon, Hiroshi
2007-01-19
We have developed and installed a new Display-type ANAlyzer (DIANA) at Ritsumeikan SR center BL-7. We measured the angle-integrated energy distribution curve of poly-crystal gold and the photoelectron intensity angular distribution (PIAD) of HOPG to estimate the total energy resolution and to check the condition of the analyzer. The total energy resolution ({delta}E/E) is up to 0.78%, which is much higher than the old type. The PIAD of HOPG we obtained was the ring pattern as expected. Therefore, a detailed three-dimensional Fermi surface mapping and an analysis of the atomic orbitals constituting the electron energy bands are possible by combining them with a linearly polarized synchrotron radiation.
Embedded-cluster calculations in a numeric atomic orbital density-functional theory framework
NASA Astrophysics Data System (ADS)
Berger, Daniel; Logsdail, Andrew J.; Oberhofer, Harald; Farrow, Matthew R.; Catlow, C. Richard A.; Sherwood, Paul; Sokol, Alexey A.; Blum, Volker; Reuter, Karsten
2014-07-01
We integrate the all-electron electronic structure code FHI-aims into the general ChemShell package for solid-state embedding quantum and molecular mechanical (QM/MM) calculations. A major undertaking in this integration is the implementation of pseudopotential functionality into FHI-aims to describe cations at the QM/MM boundary through effective core potentials and therewith prevent spurious overpolarization of the electronic density. Based on numeric atomic orbital basis sets, FHI-aims offers particularly efficient access to exact exchange and second order perturbation theory, rendering the established QM/MM setup an ideal tool for hybrid and double-hybrid level density functional theory calculations of solid systems. We illustrate this capability by calculating the reduction potential of Fe in the Fe-substituted ZSM-5 zeolitic framework and the reaction energy profile for (photo-)catalytic water oxidation at TiO2(110).
Embedded-cluster calculations in a numeric atomic orbital density-functional theory framework.
Berger, Daniel; Logsdail, Andrew J; Oberhofer, Harald; Farrow, Matthew R; Catlow, C Richard A; Sherwood, Paul; Sokol, Alexey A; Blum, Volker; Reuter, Karsten
2014-07-14
We integrate the all-electron electronic structure code FHI-aims into the general ChemShell package for solid-state embedding quantum and molecular mechanical (QM/MM) calculations. A major undertaking in this integration is the implementation of pseudopotential functionality into FHI-aims to describe cations at the QM/MM boundary through effective core potentials and therewith prevent spurious overpolarization of the electronic density. Based on numeric atomic orbital basis sets, FHI-aims offers particularly efficient access to exact exchange and second order perturbation theory, rendering the established QM/MM setup an ideal tool for hybrid and double-hybrid level density functional theory calculations of solid systems. We illustrate this capability by calculating the reduction potential of Fe in the Fe-substituted ZSM-5 zeolitic framework and the reaction energy profile for (photo-)catalytic water oxidation at TiO2(110).
New Display-type Analyzer for Three-dimensional Fermi Surface Mapping and Atomic Orbital Analysis
NASA Astrophysics Data System (ADS)
Takahashi, Nobuaki; Matsui, Fumihiko; Matsuda, Hiroyuki; Shigenai, Shin; Hirama, Yoshiteru; Hamada, Yoji; Nakanishi, Koji; Namba, Hidetoshi; Kitamura, Toshiro; Soejima, Hiroyoshi; Daimon, Hiroshi
2007-01-01
We have developed and installed a new Display-type ANAlyzer (DIANA) at Ritsumeikan SR center BL-7. We measured the angle-integrated energy distribution curve of poly-crystal gold and the photoelectron intensity angular distribution (PIAD) of HOPG to estimate the total energy resolution and to check the condition of the analyzer. The total energy resolution (ΔE/E) is up to 0.78%, which is much higher than the old type. The PIAD of HOPG we obtained was the ring pattern as expected. Therefore, a detailed three-dimensional Fermi surface mapping and an analysis of the atomic orbitals constituting the electron energy bands are possible by combining them with a linearly polarized synchrotron radiation.
Embedded-cluster calculations in a numeric atomic orbital density-functional theory framework
Berger, Daniel Oberhofer, Harald; Reuter, Karsten; Logsdail, Andrew J. Farrow, Matthew R.; Catlow, C. Richard A.; Sokol, Alexey A.; Sherwood, Paul; Blum, Volker
2014-07-14
We integrate the all-electron electronic structure code FHI-aims into the general ChemShell package for solid-state embedding quantum and molecular mechanical (QM/MM) calculations. A major undertaking in this integration is the implementation of pseudopotential functionality into FHI-aims to describe cations at the QM/MM boundary through effective core potentials and therewith prevent spurious overpolarization of the electronic density. Based on numeric atomic orbital basis sets, FHI-aims offers particularly efficient access to exact exchange and second order perturbation theory, rendering the established QM/MM setup an ideal tool for hybrid and double-hybrid level density functional theory calculations of solid systems. We illustrate this capability by calculating the reduction potential of Fe in the Fe-substituted ZSM-5 zeolitic framework and the reaction energy profile for (photo-)catalytic water oxidation at TiO{sub 2}(110)
Pardini, Lorenzo; Löffler, Stefan; Biddau, Giulio; Hambach, Ralf; Kaiser, Ute; Draxl, Claudia; Schattschneider, Peter
2016-07-15
Transmission electron microscopy has been a promising candidate for mapping atomic orbitals for a long time. Here, we explore its capabilities by a first-principles approach. For the example of defected graphene, exhibiting either an isolated vacancy or a substitutional nitrogen atom, we show that three different kinds of images are to be expected, depending on the orbital character. To judge the feasibility of visualizing orbitals in a real microscope, the effect of the optics' aberrations is simulated. We demonstrate that, by making use of energy filtering, it should indeed be possible to map atomic orbitals in a state-of-the-art transmission electron microscope. PMID:27472127
Explicitly correlated atomic orbital basis second order Møller-Plesset theory.
Hollman, David S; Wilke, Jeremiah J; Schaefer, Henry F
2013-02-14
The scope of problems treatable by ab initio wavefunction methods has expanded greatly through the application of local approximations. In particular, atomic orbital (AO) based wavefunction methods have emerged as powerful techniques for exploiting sparsity and have been applied to biomolecules as large as 1707 atoms [S. A. Maurer, D. S. Lambrecht, D. Flaig, and C. Ochsenfeld, J. Chem. Phys. 136, 144107 (2012)]. Correlated wavefunction methods, however, converge notoriously slowly to the basis set limit and, excepting the use of large basis sets, will suffer from a severe basis set incompleteness error (BSIE). The use of larger basis sets is prohibitively expensive for AO basis methods since, for example, second-order Møller-Plesset perturbation theory (MP2) scales linearly with the number of atoms, but still scales as O(N(5)) in the number of functions per atom. Explicitly correlated F12 methods have been shown to drastically reduce BSIE for even modestly sized basis sets. In this work, we therefore explore an atomic orbital based formulation of explicitly correlated MP2-F12 theory. We present working equations for the new method, which produce results identical to the widely used molecular orbital (MO) version of MP2-F12 without resorting to a delocalized MO basis. We conclude with a discussion of several possible approaches to a priori screening of contraction terms in our method and the prospects for a linear scaling implementation of AO-MP2-F12. The discussion includes concrete examples involving noble gas dimers and linear alkane chains.
ERIC Educational Resources Information Center
Rhile, Ian J.
2014-01-01
Atomic orbitals are a theme throughout the undergraduate chemistry curriculum, and visualizing them has been a theme in this journal. Contour plots as isosurfaces or contour lines in a plane are the most familiar representations of the hydrogen wave functions. In these representations, a surface of a fixed value of the wave function ? is plotted…
NASA Astrophysics Data System (ADS)
Reeves, Kyle; Kanai, Yosuke
2013-03-01
The concept of oxidation state of atoms in molecules and materials is widely used to predict and understand chemical and physical properties. This concept is perhaps driven more empirically than by any rigorous criteria differentiating one oxidation state from another. Within the oxidation state framework, an integer number of electrons is assigned to the nuclei within a system. In practice, a distribution of electron density makes it difficult to quantify such discrete assignments without some ambiguities. We explore three different charge analysis approaches in density functional theory calculations for addressing the oxidation state of important organometallic molecules [Ru(bpy)3]2+ and [Ru(bpy)3]3+, which are widely used for solar energy conversion applications. Bader charge analysis, Wannier function analysis, and atomic orbital projection are employed in this work. Given the highly-localized nature of the d-electrons of the ruthenium atom, the charge analysis methods are also compared with Hubbard-U correction. We also discuss how the solvation by water molecules influences the oxidation state characterization for these organometallic complexes.
Lin, Lin; Chen, Mohan; Yang, Chao; He, Lixin
2012-02-10
We describe how to apply the recently developed pole expansion plus selected inversion (PEpSI) technique to Kohn-Sham density function theory (DFT) electronic structure calculations that are based on atomic orbital discretization. We give analytic expressions for evaluating charge density, total energy, Helmholtz free energy and atomic forces without using the eigenvalues and eigenvectors of the Kohn-Sham Hamiltonian. We also show how to update the chemical potential without using Kohn-Sham eigenvalues. The advantage of using PEpSI is that it has a much lower computational complexity than that associated with the matrix diagonalization procedure. We demonstrate the performance gain by comparing the timing of PEpSI with that of diagonalization on insulating and metallic nanotubes. For these quasi-1D systems, the complexity of PEpSI is linear with respect to the number of atoms. This linear scaling can be observed in our computational experiments when the number of atoms in a nanotube is larger than a few hundreds. Both the wall clock time and the memory requirement of PEpSI is modest. This makes it even possible to perform Kohn-Sham DFT calculations for 10,000-atom nanotubes on a single processor. We also show that the use of PEpSI does not lead to loss of accuracy required in a practical DFT calculation.
Liquid Water through Density-Functional Molecular Dynamics: Plane-Wave vs Atomic-Orbital Basis Sets.
Miceli, Giacomo; Hutter, Jürg; Pasquarello, Alfredo
2016-08-01
We determine and compare structural, dynamical, and electronic properties of liquid water at near ambient conditions through density-functional molecular dynamics simulations, when using either plane-wave or atomic-orbital basis sets. In both frameworks, the electronic structure and the atomic forces are self-consistently determined within the same theoretical scheme based on a nonlocal density functional accounting for van der Waals interactions. The overall properties of liquid water achieved within the two frameworks are in excellent agreement with each other. Thus, our study supports that implementations with plane-wave or atomic-orbital basis sets yield equivalent results and can be used indiscriminately in study of liquid water or aqueous solutions.
Liquid Water through Density-Functional Molecular Dynamics: Plane-Wave vs Atomic-Orbital Basis Sets.
Miceli, Giacomo; Hutter, Jürg; Pasquarello, Alfredo
2016-08-01
We determine and compare structural, dynamical, and electronic properties of liquid water at near ambient conditions through density-functional molecular dynamics simulations, when using either plane-wave or atomic-orbital basis sets. In both frameworks, the electronic structure and the atomic forces are self-consistently determined within the same theoretical scheme based on a nonlocal density functional accounting for van der Waals interactions. The overall properties of liquid water achieved within the two frameworks are in excellent agreement with each other. Thus, our study supports that implementations with plane-wave or atomic-orbital basis sets yield equivalent results and can be used indiscriminately in study of liquid water or aqueous solutions. PMID:27434607
NASA Astrophysics Data System (ADS)
Thomas, Patrick Ryan
Large simulation cell sizes, relativistic effects, and the need to correctly model excited state properties are major impediments to the accurate prediction of the optical properties of candidate materials for solid-state laser crystal and luminescent applications. To overcome these challenges, new methods must be created to improve the electron orbital wavefunction and interactions. In this work, a method has been developed to create new analytical four-component, fully-relativistic and single-component scalar relativistic descriptions of the atomic orbital wave functions from Grasp2K numerically represented atomic orbitals. In addition, adapted theory for the calculation of the relativistic kinetic energy contribution to Hamiltonian which bypasses directly solving the Dirac equation has been explicated. The orbital description improvements are tested against YAG, YBCO, SnO2 and BiF3. The improvements to the basis set reflect an improvement in both computational speed and accuracy.
The splitting of atomic orbitals with a common principal quantum number revisited: np vs. ns.
Katriel, Jacob
2012-04-14
Atomic orbitals with a common principal quantum number are degenerate, as in the hydrogen atom, in the absence of interelectronic repulsion. Due to the virial theorem, electrons in such orbitals experience equal nuclear attractions. Comparing states of several-electron atoms that differ by the occupation of orbitals with a common principal quantum number, such as 1s(2) 2s vs. 1s(2) 2p, we find that although the difference in energies, ΔE, is due to the interelectronic repulsion term in the Hamiltonian, the difference between the interelectronic repulsions, ΔC, makes a smaller contribution to ΔE than the corresponding difference between the nuclear attractions, ΔL. Analysis of spectroscopic data for atomic isoelectronic sequences allows an extensive investigation of these issues. In the low nuclear charge range of pertinent isoelectronic sequences, i.e., for neutral atoms and mildly positively charged ions, it is found that ΔC actually reverses its sign. About 96% of the nuclear attraction difference between the 6p (2)P and the 6s (2)S states of the Cs atom is cancelled by the corresponding interelectronic repulsion difference. From the monotonic increase of ΔE with Z it follows (via the Hellmann-Feynman theorem) that ΔL > 0. Upon increasing the nuclear charge along an atomic isoelectronic sequence with a single electron outside a closed shell from Z(c), the critical charge below which the outmost electron is not bound, to infinity, the ratio ΔC/ΔL increases monotonically from lim(Z→Z(c)(+))ΔC/ΔL=-1 to lim(Z→∞)ΔC/ΔL=1. These results should allow for a more nuanced discussion than is usually encountered of the crude electronic structure of many-electron atoms and the structure of the periodic table.
The splitting of atomic orbitals with a common principal quantum number revisited: np vs. ns.
Katriel, Jacob
2012-04-14
Atomic orbitals with a common principal quantum number are degenerate, as in the hydrogen atom, in the absence of interelectronic repulsion. Due to the virial theorem, electrons in such orbitals experience equal nuclear attractions. Comparing states of several-electron atoms that differ by the occupation of orbitals with a common principal quantum number, such as 1s(2) 2s vs. 1s(2) 2p, we find that although the difference in energies, ΔE, is due to the interelectronic repulsion term in the Hamiltonian, the difference between the interelectronic repulsions, ΔC, makes a smaller contribution to ΔE than the corresponding difference between the nuclear attractions, ΔL. Analysis of spectroscopic data for atomic isoelectronic sequences allows an extensive investigation of these issues. In the low nuclear charge range of pertinent isoelectronic sequences, i.e., for neutral atoms and mildly positively charged ions, it is found that ΔC actually reverses its sign. About 96% of the nuclear attraction difference between the 6p (2)P and the 6s (2)S states of the Cs atom is cancelled by the corresponding interelectronic repulsion difference. From the monotonic increase of ΔE with Z it follows (via the Hellmann-Feynman theorem) that ΔL > 0. Upon increasing the nuclear charge along an atomic isoelectronic sequence with a single electron outside a closed shell from Z(c), the critical charge below which the outmost electron is not bound, to infinity, the ratio ΔC/ΔL increases monotonically from lim(Z→Z(c)(+))ΔC/ΔL=-1 to lim(Z→∞)ΔC/ΔL=1. These results should allow for a more nuanced discussion than is usually encountered of the crude electronic structure of many-electron atoms and the structure of the periodic table. PMID:22502506
NASA Astrophysics Data System (ADS)
Lin, Lin; Chen, Mohan; Yang, Chao; He, Lixin
2013-07-01
We describe how to apply the recently developed pole expansion and selected inversion (PEXSI) technique to Kohn-Sham density function theory (DFT) electronic structure calculations that are based on atomic orbital discretization. We give analytic expressions for evaluating the charge density, the total energy, the Helmholtz free energy and the atomic forces (including both the Hellmann-Feynman force and the Pulay force) without using the eigenvalues and eigenvectors of the Kohn-Sham Hamiltonian. We also show how to update the chemical potential without using Kohn-Sham eigenvalues. The advantage of using PEXSI is that it has a computational complexity much lower than that associated with the matrix diagonalization procedure. We demonstrate the performance gain by comparing the timing of PEXSI with that of diagonalization on insulating and metallic nanotubes. For these quasi-1D systems, the complexity of PEXSI is linear with respect to the number of atoms. This linear scaling can be observed in our computational experiments when the number of atoms in a nanotube is larger than a few hundreds. Both the wall clock time and the memory requirement of PEXSI are modest. This even makes it possible to perform Kohn-Sham DFT calculations for 10 000-atom nanotubes with a sequential implementation of the selected inversion algorithm. We also perform an accurate geometry optimization calculation on a truncated (8, 0) boron nitride nanotube system containing 1024 atoms. Numerical results indicate that the use of PEXSI does not lead to loss of the accuracy required in a practical DFT calculation.
NASA Astrophysics Data System (ADS)
Igenbergs, K.; Schweinzer, J.; Aumayr, F.
2009-12-01
Charge exchange in Be4+-H(n = 1, 2) collisions was studied using the atomic-orbital close-coupling formalism in its impact parameter description and applying electron translational factors. Calculations were carried out in the energy range of 1-750 keV amu-1 with fully stripped beryllium ions impacting on atomic hydrogen in its ground state (1s) and in the excited n = 2 states. An optimized description of both collision centres was determined by analysing the convergence of the total cross sections and also by comparison with other theoretical approaches. This optimized description consists of up to 170 basis states involving hydrogen-like states and pseudostates. We present total, n-resolved as well as nell-resolved cross sections. The latter are needed to evaluate the emission cross sections in two limiting collisional plasma environments, i.e. single-collisional and multi-collisional. The calculated emission cross sections are compared with experimental data from the fusion experiment JET. Taking the experimental environment and certain characteristics of the theoretical methods into account, the agreement can be considered to be quite good.
Grimme, Stefan; Brandenburg, Jan Gerit; Bannwarth, Christoph; Hansen, Andreas
2015-08-01
A density functional theory (DFT) based composite electronic structure approach is proposed to efficiently compute structures and interaction energies in large chemical systems. It is based on the well-known and numerically robust Perdew-Burke-Ernzerhoff (PBE) generalized-gradient-approximation in a modified global hybrid functional with a relatively large amount of non-local Fock-exchange. The orbitals are expanded in Ahlrichs-type valence-double zeta atomic orbital (AO) Gaussian basis sets, which are available for many elements. In order to correct for the basis set superposition error (BSSE) and to account for the important long-range London dispersion effects, our well-established atom-pairwise potentials are used. In the design of the new method, particular attention has been paid to an accurate description of structural parameters in various covalent and non-covalent bonding situations as well as in periodic systems. Together with the recently proposed three-fold corrected (3c) Hartree-Fock method, the new composite scheme (termed PBEh-3c) represents the next member in a hierarchy of "low-cost" electronic structure approaches. They are mainly free of BSSE and account for most interactions in a physically sound and asymptotically correct manner. PBEh-3c yields good results for thermochemical properties in the huge GMTKN30 energy database. Furthermore, the method shows excellent performance for non-covalent interaction energies in small and large complexes. For evaluating its performance on equilibrium structures, a new compilation of standard test sets is suggested. These consist of small (light) molecules, partially flexible, medium-sized organic molecules, molecules comprising heavy main group elements, larger systems with long bonds, 3d-transition metal systems, non-covalently bound complexes (S22 and S66×8 sets), and peptide conformations. For these sets, overall deviations from accurate reference data are smaller than for various other tested DFT methods
NASA Astrophysics Data System (ADS)
Grimme, Stefan; Brandenburg, Jan Gerit; Bannwarth, Christoph; Hansen, Andreas
2015-08-01
A density functional theory (DFT) based composite electronic structure approach is proposed to efficiently compute structures and interaction energies in large chemical systems. It is based on the well-known and numerically robust Perdew-Burke-Ernzerhoff (PBE) generalized-gradient-approximation in a modified global hybrid functional with a relatively large amount of non-local Fock-exchange. The orbitals are expanded in Ahlrichs-type valence-double zeta atomic orbital (AO) Gaussian basis sets, which are available for many elements. In order to correct for the basis set superposition error (BSSE) and to account for the important long-range London dispersion effects, our well-established atom-pairwise potentials are used. In the design of the new method, particular attention has been paid to an accurate description of structural parameters in various covalent and non-covalent bonding situations as well as in periodic systems. Together with the recently proposed three-fold corrected (3c) Hartree-Fock method, the new composite scheme (termed PBEh-3c) represents the next member in a hierarchy of "low-cost" electronic structure approaches. They are mainly free of BSSE and account for most interactions in a physically sound and asymptotically correct manner. PBEh-3c yields good results for thermochemical properties in the huge GMTKN30 energy database. Furthermore, the method shows excellent performance for non-covalent interaction energies in small and large complexes. For evaluating its performance on equilibrium structures, a new compilation of standard test sets is suggested. These consist of small (light) molecules, partially flexible, medium-sized organic molecules, molecules comprising heavy main group elements, larger systems with long bonds, 3d-transition metal systems, non-covalently bound complexes (S22 and S66×8 sets), and peptide conformations. For these sets, overall deviations from accurate reference data are smaller than for various other tested DFT methods
Grimme, Stefan Brandenburg, Jan Gerit; Bannwarth, Christoph; Hansen, Andreas
2015-08-07
A density functional theory (DFT) based composite electronic structure approach is proposed to efficiently compute structures and interaction energies in large chemical systems. It is based on the well-known and numerically robust Perdew-Burke-Ernzerhoff (PBE) generalized-gradient-approximation in a modified global hybrid functional with a relatively large amount of non-local Fock-exchange. The orbitals are expanded in Ahlrichs-type valence-double zeta atomic orbital (AO) Gaussian basis sets, which are available for many elements. In order to correct for the basis set superposition error (BSSE) and to account for the important long-range London dispersion effects, our well-established atom-pairwise potentials are used. In the design of the new method, particular attention has been paid to an accurate description of structural parameters in various covalent and non-covalent bonding situations as well as in periodic systems. Together with the recently proposed three-fold corrected (3c) Hartree-Fock method, the new composite scheme (termed PBEh-3c) represents the next member in a hierarchy of “low-cost” electronic structure approaches. They are mainly free of BSSE and account for most interactions in a physically sound and asymptotically correct manner. PBEh-3c yields good results for thermochemical properties in the huge GMTKN30 energy database. Furthermore, the method shows excellent performance for non-covalent interaction energies in small and large complexes. For evaluating its performance on equilibrium structures, a new compilation of standard test sets is suggested. These consist of small (light) molecules, partially flexible, medium-sized organic molecules, molecules comprising heavy main group elements, larger systems with long bonds, 3d-transition metal systems, non-covalently bound complexes (S22 and S66×8 sets), and peptide conformations. For these sets, overall deviations from accurate reference data are smaller than for various other tested DFT
Gusso, Michele
2008-01-28
A detailed study on the accuracy attainable with numerical atomic orbitals in the context of pseudopotential first-principles density functional theory is presented. Dimers of first- and second-row elements are analyzed: bond lengths, atomization energies, and Kohn-Sham eigenvalue spectra obtained with localized orbitals and with plane-wave basis sets are compared. For each dimer, the cutoff radius, the shape, and the number of the atomic basis orbitals are varied in order to maximize the accuracy of the calculations. Optimized atomic orbitals are obtained following two routes: (i) maximization of the projection of plane wave results into atomic orbital basis sets and (ii) minimization of the total energy with respect to a set of primitive atomic orbitals as implemented in the OPENMX software package. It is found that by optimizing the numerical basis, chemical accuracy can be obtained even with a small set of orbitals.
NASA Astrophysics Data System (ADS)
Agapito, Luis; Calzolari, Arrigo; Ferretti, Andrea; Nardelli, Marco
2013-03-01
Metal-organic frameworks (MOF) are a new class of artificial crystalline materials. Because of their flexibility for synthesis and instrinsic ultrahigh surface area and porosity, MOFs show superior performance in gas storage, catalysis, and sensing applications. We use an efficient projection of plane-wave wavefunctions onto atomic orbitals for studying the electronic properties of these intriguing materials. The present scheme harnesses the robust periodic algorithms and systematic convergence of the plane-wave method for an atomistic electronic (Landauer conductance) and chemical (charge transfer, bond and atomic charge) analysis that provides guidelines for the design of MOF electronic materials.
NASA Astrophysics Data System (ADS)
Wang, Mingliang; Wong, Chung F.; Liu, Jianhong; Zhang, Peixin
2007-07-01
We have successfully coupled the Kohn-Sham with Poisson-Boltzmann equations to predict the solvation free energy, where the Kohn-Sham equations were solved by implementing the flexible pseudo atomic orbitals as in S IESTA package. It was found that the calculated solvation free energy is in good agreement with experimental results for small neutral molecules, and its standard error is 1.33 kcal/mol, the correlation coefficient is 0.97. Due to its high efficiency and accuracy, the proposed model can be a promising tool for computing solvation free energies in computer aided drug design in future.
Hohenstein, Edward G.; Luehr, Nathan; Ufimtsev, Ivan S.; Martínez, Todd J.
2015-06-14
Despite its importance, state-of-the-art algorithms for performing complete active space self-consistent field (CASSCF) computations have lagged far behind those for single reference methods. We develop an algorithm for the CASSCF orbital optimization that uses sparsity in the atomic orbital (AO) basis set to increase the applicability of CASSCF. Our implementation of this algorithm uses graphical processing units (GPUs) and has allowed us to perform CASSCF computations on molecular systems containing more than one thousand atoms. Additionally, we have implemented analytic gradients of the CASSCF energy; the gradients also benefit from GPU acceleration as well as sparsity in the AO basis.
NASA Astrophysics Data System (ADS)
Deeney, Tony; O'Sullivan, Colm
2014-09-01
The Bohr-Sommerfeld atomic model is recast in the language of wave-particle duality and it is shown that requirements equivalent to the Sommerfeld-Wilson quantisation conditions arise naturally in this context. It is suggested that treating the one-electron atom in this way provides a useful introduction for students prior to encountering the more formal analysis based on the solution of the Schrödinger equation.
Bachler, Vinzenz
2007-09-01
Localized bonding schemes and their weights have been obtained for the pi-electron system of nitrone by expanding complete active space self-consistent field wave functions into a set of Slater determinants composed of orthogonal natural atomic orbitals (NAOs) of Weinhold and Landis (Valency and Bonding: A Natural Bond Orbital Donor-Acceptor Perspective, 2005). Thus, the derived bonding schemes are close to orthogonal valence bond structures. The calculated sequence of bonding scheme weights accords with the sequence of genuine resonance structure weights derived previously by Ohanessian and Hiberty (Chem Phys Lett 1987, 137, 437), who employed nonorthogonal atomic orbitals. This accord supports the notion that NAOs form an appropriate orthogonal one-electron basis for expanding complete active space self-consistent field wave functions into meaningful bonding schemes and their weights.
Visualization of atom's orbits.
Kim, Byungwhan
2014-02-01
High-resolution imaging techniques have been used to obtain views of internal shapes of single atoms or columns of atoms. This review article focuses on the visualization of internal atomic structures such as the configurations of electron orbits confined to atoms. This is accomplished by applying visualization techniques to the reported images of atoms or molecules as well as static and dynamic ions in a plasma. It was found that the photon and electron energies provide macroscopic and microscopic views of the orbit structures of atoms, respectively. The laser-imaged atoms showed a rugged orbit structure, containing alternating dark and bright orbits believed to be the pathways for an externally supplied laser energy and internally excited electron energy, respectively. By contrast, the atoms taken by the electron microscopy provided a structure of fine electron orbits, systematically formed in increasing order of grayscale representing the energy state of an orbit. This structure was identical to those of the plasma ions. The visualized electronic structures played a critical role in clarifying vague postulates made in the Bohr model. Main features proposed in the atomic model are the dynamic orbits absorbing an externally supplied electromagnetic energy, electron emission from them while accompanying light radiation, and frequency of electron waves not light. The light-accompanying electrons and ionic speckles induced by laser light signify that light is composed of electrons and ions.
Ji, Wen-Xin; Xu, Wei; Schwarz, W H Eugen; Wang, Shu-Guang
2015-03-15
Lanthanide trihalide molecules LnX3 (X = F, Cl, Br, I) were quantum chemically investigated, in particular detail for Ln = Lu (lutetium). We applied density functional theory (DFT) at the nonrelativistic and scalar and SO-coupled relativistic levels, and also the ab initio coupled cluster approach. The chemically active electron shells of the lanthanide atoms comprise the 5d and 6s (and 6p) valence atomic orbitals (AO) and also the filled inner 4f semivalence and outer 5p semicore shells. Four different frozen-core approximations for Lu were compared: the (1s(2) -4d(10) ) [Pd] medium core, the [Pd+5s(2) 5p(6) = Xe] and [Pd+4f(14) ] large cores, and the [Pd+4f(14) +5s(2) 5p(6) ] very large core. The errors of LuX bonding are more serious on freezing the 5p(6) shell than the 4f(14) shell, more serious upon core-freezing than on the effective-core-potential approximation. The LnX distances correlate linearly with the AO radii of the ionic outer shells, Ln(3+) -5p(6) and X(-) -np(6) , characteristic for dominantly ionic Ln(3+) -X(-) binding. The heavier halogen atoms also bind covalently with the Ln-5d shell. Scalar relativistic effects contract and destabilize the LuX bonds, spin orbit coupling hardly affects the geometries but the bond energies, owing to SO effects in the free atoms. The relativistic changes of bond energy BE, bond length Re , bond force k, and bond stretching frequency vs do not follow the simple rules of Badger and Gordy (Re ∼BE∼k∼vs ). The so-called degeneracy-driven covalence, meaning strong mixing of accidentally near-degenerate, nearly nonoverlapping AOs without BE contribution is critically discussed.
Ji, Wen-Xin; Xu, Wei; Schwarz, W H Eugen; Wang, Shu-Guang
2015-03-15
Lanthanide trihalide molecules LnX3 (X = F, Cl, Br, I) were quantum chemically investigated, in particular detail for Ln = Lu (lutetium). We applied density functional theory (DFT) at the nonrelativistic and scalar and SO-coupled relativistic levels, and also the ab initio coupled cluster approach. The chemically active electron shells of the lanthanide atoms comprise the 5d and 6s (and 6p) valence atomic orbitals (AO) and also the filled inner 4f semivalence and outer 5p semicore shells. Four different frozen-core approximations for Lu were compared: the (1s(2) -4d(10) ) [Pd] medium core, the [Pd+5s(2) 5p(6) = Xe] and [Pd+4f(14) ] large cores, and the [Pd+4f(14) +5s(2) 5p(6) ] very large core. The errors of LuX bonding are more serious on freezing the 5p(6) shell than the 4f(14) shell, more serious upon core-freezing than on the effective-core-potential approximation. The LnX distances correlate linearly with the AO radii of the ionic outer shells, Ln(3+) -5p(6) and X(-) -np(6) , characteristic for dominantly ionic Ln(3+) -X(-) binding. The heavier halogen atoms also bind covalently with the Ln-5d shell. Scalar relativistic effects contract and destabilize the LuX bonds, spin orbit coupling hardly affects the geometries but the bond energies, owing to SO effects in the free atoms. The relativistic changes of bond energy BE, bond length Re , bond force k, and bond stretching frequency vs do not follow the simple rules of Badger and Gordy (Re ∼BE∼k∼vs ). The so-called degeneracy-driven covalence, meaning strong mixing of accidentally near-degenerate, nearly nonoverlapping AOs without BE contribution is critically discussed. PMID:25565146
Rethinking Formalisms in Formal Education
ERIC Educational Resources Information Center
Nathan, Mitchell J.
2012-01-01
I explore a belief about learning and teaching that is commonly held in education and society at large that nonetheless is deeply flawed. The belief asserts that mastery of "formalisms"--specialized representations such as symbolic equations and diagrams with no inherent meaning except that which is established by convention--is prerequisite to…
NASA Technical Reports Server (NTRS)
Denning, Peter J.
1991-01-01
The ongoing debate over the role of formalism and formal specifications in software features many speakers with diverse positions. Yet, in the end, they share the conviction that the requirements of a software system can be unambiguously specified, that acceptable software is a product demonstrably meeting the specifications, and that the design process can be carried out with little interaction between designers and users once the specification has been agreed to. This conviction is part of a larger paradigm prevalent in American management thinking, which holds that organizations are systems that can be precisely specified and optimized. This paradigm, which traces historically to the works of Frederick Taylor in the early 1900s, is no longer sufficient for organizations and software systems today. In the domain of software, a new paradigm, called user-centered design, overcomes the limitations of pure formalism. Pioneered in Scandinavia, user-centered design is spreading through Europe and is beginning to make its way into the U.S.
Schurkus, Henry F; Ochsenfeld, Christian
2016-01-21
An atomic-orbital (AO) reformulation of the random-phase approximation (RPA) correlation energy is presented allowing to reduce the steep computational scaling to linear, so that large systems can be studied on simple desktop computers with fully numerically controlled accuracy. Our AO-RPA formulation introduces a contracted double-Laplace transform and employs the overlap-metric resolution-of-the-identity. First timings of our pilot code illustrate the reduced scaling with systems comprising up to 1262 atoms and 10 090 basis functions. .
NASA Astrophysics Data System (ADS)
Schurkus, Henry F.; Ochsenfeld, Christian
2016-01-01
An atomic-orbital (AO) reformulation of the random-phase approximation (RPA) correlation energy is presented allowing to reduce the steep computational scaling to linear, so that large systems can be studied on simple desktop computers with fully numerically controlled accuracy. Our AO-RPA formulation introduces a contracted double-Laplace transform and employs the overlap-metric resolution-of-the-identity. First timings of our pilot code illustrate the reduced scaling with systems comprising up to 1262 atoms and 10 090 basis functions.
Sure, Rebecca; Brandenburg, Jan Gerit; Grimme, Stefan
2016-04-01
In quantum chemical computations the combination of Hartree-Fock or a density functional theory (DFT) approximation with relatively small atomic orbital basis sets of double-zeta quality is still widely used, for example, in the popular B3LYP/6-31G* approach. In this Review, we critically analyze the two main sources of error in such computations, that is, the basis set superposition error on the one hand and the missing London dispersion interactions on the other. We review various strategies to correct those errors and present exemplary calculations on mainly noncovalently bound systems of widely varying size. Energies and geometries of small dimers, large supramolecular complexes, and molecular crystals are covered. We conclude that it is not justified to rely on fortunate error compensation, as the main inconsistencies can be cured by modern correction schemes which clearly outperform the plain mean-field methods. PMID:27308221
Kerley, G.I.
1988-10-01
Atomic orbital energies and radial expectation values are tabulated for the ground state electronic configuration of all elements with Z less than or equal to 103 and for all orbitals having principal quantum numbers n less than or equal to 8. These tables have been developed for use in a model of electronic excitation and ionization that requires orbital data for both the occupied and unoccupied orbitals. The wavefunctions were calculated by the Dirac-Hartree-Fock-Slater method, with a local exchange potential due to Liberman. This potential has the Coulombic form at large distances from the nucleus, with the result that both the occupied and unoccupied orbitals are bound states. The complete nonlocal exchange expression was used to compute the orbital energies. The results are in good agreement with full Dirac-Hartree-Fock calculations for the occupied orbitals. 22 refs., 2 tabs.
Sure, Rebecca; Brandenburg, Jan Gerit; Grimme, Stefan
2016-04-01
In quantum chemical computations the combination of Hartree-Fock or a density functional theory (DFT) approximation with relatively small atomic orbital basis sets of double-zeta quality is still widely used, for example, in the popular B3LYP/6-31G* approach. In this Review, we critically analyze the two main sources of error in such computations, that is, the basis set superposition error on the one hand and the missing London dispersion interactions on the other. We review various strategies to correct those errors and present exemplary calculations on mainly noncovalently bound systems of widely varying size. Energies and geometries of small dimers, large supramolecular complexes, and molecular crystals are covered. We conclude that it is not justified to rely on fortunate error compensation, as the main inconsistencies can be cured by modern correction schemes which clearly outperform the plain mean-field methods.
Sure, Rebecca; Brandenburg, Jan Gerit
2015-01-01
Abstract In quantum chemical computations the combination of Hartree–Fock or a density functional theory (DFT) approximation with relatively small atomic orbital basis sets of double‐zeta quality is still widely used, for example, in the popular B3LYP/6‐31G* approach. In this Review, we critically analyze the two main sources of error in such computations, that is, the basis set superposition error on the one hand and the missing London dispersion interactions on the other. We review various strategies to correct those errors and present exemplary calculations on mainly noncovalently bound systems of widely varying size. Energies and geometries of small dimers, large supramolecular complexes, and molecular crystals are covered. We conclude that it is not justified to rely on fortunate error compensation, as the main inconsistencies can be cured by modern correction schemes which clearly outperform the plain mean‐field methods. PMID:27308221
Experimental Evaluation of a Planning Language Suitable for Formal Verification
NASA Technical Reports Server (NTRS)
Butler, Rick W.; Munoz, Cesar A.; Siminiceanu, Radu I.
2008-01-01
The marriage of model checking and planning faces two seemingly diverging alternatives: the need for a planning language expressive enough to capture the complexity of real-life applications, as opposed to a language simple, yet robust enough to be amenable to exhaustive verification and validation techniques. In an attempt to reconcile these differences, we have designed an abstract plan description language, ANMLite, inspired from the Action Notation Modeling Language (ANML) [17]. We present the basic concepts of the ANMLite language as well as an automatic translator from ANMLite to the model checker SAL (Symbolic Analysis Laboratory) [7]. We discuss various aspects of specifying a plan in terms of constraints and explore the implications of choosing a robust logic behind the specification of constraints, rather than simply propose a new planning language. Additionally, we provide an initial assessment of the efficiency of model checking to search for solutions of planning problems. To this end, we design a basic test benchmark and study the scalability of the generated SAL models in terms of plan complexity.
NASA Astrophysics Data System (ADS)
Teng, H.; Fujiwara, T.; Hoshi, T.; Sogabe, T.; Zhang, S.-L.; Yamamoto, S.
2011-04-01
The need for large-scale electronic structure calculations arises recently in the field of material physics, and efficient and accurate algebraic methods for large simultaneous linear equations become greatly important. We investigate the generalized shifted conjugate orthogonal conjugate gradient method, the generalized Lanczos method, and the generalized Arnoldi method. They are the solver methods of large simultaneous linear equations of the one-electron Schrödinger equation and map the whole Hilbert space to a small subspace called the Krylov subspace. These methods are applied to systems of fcc Au with the NRL tight-binding Hamiltonian [F. Kirchhoff , Phys. Rev. BJCOMEL1098-012110.1103/PhysRevB.63.195101 63, 195101 (2001)]. We compare results by these methods and the exact calculation and show them to be equally accurate. The system size dependence of the CPU time is also discussed. The generalized Lanczos method and the generalized Arnoldi method are the most suitable for the large-scale molecular dynamics simulations from the viewpoint of CPU time and memory size.
NASA Astrophysics Data System (ADS)
Ching, Wai-Yim; Rulis, Paul
2009-03-01
Over the last eight years, a large number of x-ray absorption near edge structure (XANES) and/or electron energy loss near edge structure (ELNES) spectroscopic calculations for complex oxides and nitrides have been performed using the supercell-OLCAO (orthogonalized linear combination of atomic orbitals) method, obtaining results in very good agreement with experiments. The method takes into account the core-hole effect and includes the dipole matrix elements calculated from ab initio wavefunctions. In this paper, we describe the method in considerable detail, emphasizing the special advantages of this method for large complex systems. Selected results are reviewed and several hitherto unpublished results are also presented. These include the Y K edge of Y ions segregated to the core of a Σ31 grain boundary in alumina, O K edges of water molecules, C K edges in different types of single walled carbon nanotubes, and the Co K edge in the cyanocobalamin (vitamin B12) molecule. On the basis of these results, it is argued that the interpretation of specific features of the calculated XANES/ELNES edges is not simple for complex material systems because of the delocalized nature of the conduction band states. The long-standing notion of the 'fingerprinting' technique for spectral interpretation of experimental data is not tenable. A better approach is to fully characterize the structure under study, using either crystalline data or accurate ab initio modeling. Comparison between calculated XANES/ELNES spectra and available measurements enables us to ascertain the validity of the modeled structure. For complex crystals or structures, it is necessary to use the weighted sum of the spectra from structurally nonequivalent sites for comparison with the measured data. Future application of the supercell-OLCAO method to complex biomolecular systems is also discussed.
Software Formal Inspections Guidebook
NASA Technical Reports Server (NTRS)
1993-01-01
The Software Formal Inspections Guidebook is designed to support the inspection process of software developed by and for NASA. This document provides information on how to implement a recommended and proven method for conducting formal inspections of NASA software. This Guidebook is a companion document to NASA Standard 2202-93, Software Formal Inspections Standard, approved April 1993, which provides the rules, procedures, and specific requirements for conducting software formal inspections. Application of the Formal Inspections Standard is optional to NASA program or project management. In cases where program or project management decide to use the formal inspections method, this Guidebook provides additional information on how to establish and implement the process. The goal of the formal inspections process as documented in the above-mentioned Standard and this Guidebook is to provide a framework and model for an inspection process that will enable the detection and elimination of defects as early as possible in the software life cycle. An ancillary aspect of the formal inspection process incorporates the collection and analysis of inspection data to effect continual improvement in the inspection process and the quality of the software subjected to the process.
Geometry and Formal Linguistics.
ERIC Educational Resources Information Center
Huff, George A.
This paper presents a method of encoding geometric line-drawings in a way which allows sets of such drawings to be interpreted as formal languages. A characterization of certain geometric predicates in terms of their properties as languages is obtained, and techniques usually associated with generative grammars and formal automata are then applied…
Federal Register 2010, 2011, 2012, 2013, 2014
2010-11-05
...; ] OFFICE OF PERSONNEL MANAGEMENT 5 CFR PART 731 RIN 3206-AL90 Suitability AGENCY: U.S. Office of Personnel... possible, of security and suitability standards. Public Trust Positions Public trust positions are those...) for a new public trust reinvestigation. Likewise, a suitability investigation based on a change...
Integrated formal operations plan
Cort, G.; Dearholt, W.; Donahue, S.; Frank, J.; Perkins, B.; Tyler, R.; Wrye, J.
1994-01-05
The concept of formal operations (that is, a collection of business practices to assure effective, accountable operations) has vexed the Laboratory for many years. To date most attempts at developing such programs have been based upon rigid, compliance-based interpretations of a veritable mountain of Department of Energy (DOE) orders, directives, notices, and standards. These DOE dictates seldom take the broad view but focus on highly specialized programs isolated from the overall context of formal operations. The result is a confusing array of specific, and often contradictory, requirements that produce a patchwork of overlapping niche programs. This unnecessary duplication wastes precious resources, dramatically increases the complexity of our work processes, and communicates a sense of confusion to our customers and regulators. Coupled with the artificial divisions that have historically existed among the Laboratory`s formal operations organizations (quality assurance, configuration management, records management, training, etc.), this approach has produced layers of increasingly vague and complex formal operations plans, each of which interprets its parent and adds additional requirements of its own. Organizational gridlock ensues whenever an activity attempts to implement these bureaucratic monstrosities. The integrated formal operations plan presented is to establish a set of requirements that must be met by an integrated formal operations program, assign responsibilities for implementation and operation of the program, and specify criteria against which the performance of the program will be measured. The accountable line manager specifies the items, processes, and information (the controlled elements) to which the formal operations program specified applies. The formal operations program is implemented using a graded approach based on the level of importance of the various controlled elements and the scope of the activities in which they are involved.
Snyder, James W.; Hohenstein, Edward G.; Luehr, Nathan; Martínez, Todd J.
2015-10-21
We recently presented an algorithm for state-averaged complete active space self-consistent field (SA-CASSCF) orbital optimization that capitalizes on sparsity in the atomic orbital basis set to reduce the scaling of computational effort with respect to molecular size. Here, we extend those algorithms to calculate the analytic gradient and nonadiabatic coupling vectors for SA-CASSCF. Combining the low computational scaling with acceleration from graphical processing units allows us to perform SA-CASSCF geometry optimizations for molecules with more than 1000 atoms. The new approach will make minimal energy conical intersection searches and nonadiabatic dynamics routine for molecular systems with O(10{sup 2}) atoms.
Formalizing Probabilistic Safety Claims
NASA Technical Reports Server (NTRS)
Herencia-Zapana, Heber; Hagen, George E.; Narkawicz, Anthony J.
2011-01-01
A safety claim for a system is a statement that the system, which is subject to hazardous conditions, satisfies a given set of properties. Following work by John Rushby and Bev Littlewood, this paper presents a mathematical framework that can be used to state and formally prove probabilistic safety claims. It also enables hazardous conditions, their uncertainties, and their interactions to be integrated into the safety claim. This framework provides a formal description of the probabilistic composition of an arbitrary number of hazardous conditions and their effects on system behavior. An example is given of a probabilistic safety claim for a conflict detection algorithm for aircraft in a 2D airspace. The motivation for developing this mathematical framework is that it can be used in an automated theorem prover to formally verify safety claims.
Software Formal Inspections Standard
NASA Technical Reports Server (NTRS)
1993-01-01
This Software Formal Inspections Standard (hereinafter referred to as Standard) is applicable to NASA software. This Standard defines the requirements that shall be fulfilled by the software formal inspections process whenever this process is specified for NASA software. The objective of this Standard is to define the requirements for a process that inspects software products to detect and eliminate defects as early as possible in the software life cycle. The process also provides for the collection and analysis of inspection data to improve the inspection process as well as the quality of the software.
Correlates of Formal Reasoning.
ERIC Educational Resources Information Center
Linn, Marcia C.; Pulos, Steven
This study of Piagetian formal reasoning in seventh grade students reports the relationships between four aspects of the ability to control variables in an experiment and the relationships between those four aspects and other constructs. The four aspects of the ability to control variables identified are: (1) set up a controlled experiment, (2)…
Formal synthesis of (+)-discodermolide.
Francavilla, Charles; Chen, Weichun; Kinder, Frederick R
2003-04-17
[structure: see text] Herein we report the formal total synthesis of (+)-discodermolide in 21 steps (longest linear sequence) from commercially available Roche ester. This synthesis features the assembly of C(9-18) and C(19-24) fragments via a metal-chelated aldol coupling reaction.
Adolescence and Formal Operations
ERIC Educational Resources Information Center
Blasi, A.; Hoeffel, E. C.
1974-01-01
Analyzes the relationship between the development of formal operations and the development of the adolescent personality, as hypothesized by Inhelder and Piaget. It is suggested that the concepts of possibility and reflectivity have a variety of meanings, and that once these meanings are examined, the logical foundation for the…
Formal modeling of robot behavior with learning.
Kirwan, Ryan; Miller, Alice; Porr, Bernd; Di Prodi, P
2013-11-01
We present formal specification and verification of a robot moving in a complex network, using temporal sequence learning to avoid obstacles. Our aim is to demonstrate the benefit of using a formal approach to analyze such a system as a complementary approach to simulation. We first describe a classical closed-loop simulation of the system and compare this approach to one in which the system is analyzed using formal verification. We show that the formal verification has some advantages over classical simulation and finds deficiencies our classical simulation did not identify. Specifically we present a formal specification of the system, defined in the Promela modeling language and show how the associated model is verified using the Spin model checker. We then introduce an abstract model that is suitable for verifying the same properties for any environment with obstacles under a given set of assumptions. We outline how we can prove that our abstraction is sound: any property that holds for the abstracted model will hold in the original (unabstracted) model.
Semisymmetric systems: Hermitian formalism
NASA Astrophysics Data System (ADS)
Buchdahl, H. A.
1995-04-01
The power series representing the characteristic function of a regular semisymmetric system involves four linearly independent rotational invariants XA (A=1,.. .,4) that jointly satisfy a quadratic identity. When the X A are appropriately chosen, this takes the form -(X1)2-(X2 )2-(X3)2+( X4)2=0 . The XA are thus the components of a null vector in a four-dimensional Euclidean space whose metric is gAB: =diag(-1,-1 ,-1,1) . Such a vector is equivalent to a simple 2-spinor xi alpha . The intrinsic presence of a spin vector in the formalism used hitherto suggests that it might be of advantage to replace the latter with an explicit 2-spinor formalism. A way of doing this is examined.
Biodiversity: Habitat Suitability
Habitat suitability quantifies the relationship between species and habitat, and is evaluated according to the species’ fitness (i.e. proportion of birth rate to death rate). Even though it might maximize evolutionary success, species are not always in habitat that optimizes fit...
Formalizing the concept of sound.
Kaper, H. G.; Tipei, S.
1999-08-03
The notion of formalized music implies that a musical composition can be described in mathematical terms. In this article we explore some formal aspects of music and propose a framework for an abstract approach.
Formalizing Space Shuttle Software Requirements
NASA Technical Reports Server (NTRS)
Crow, Judith; DiVito, Ben L.
1996-01-01
This paper describes two case studies in which requirements for new flight-software subsystems on NASA's Space Shuttle were analyzed, one using standard formal specification techniques, the other using state exploration. These applications serve to illustrate three main theses: (1) formal methods can complement conventional requirements analysis processes effectively, (2) formal methods confer benefits regardless of how extensively they are adopted and applied, and (3) formal methods are most effective when they are judiciously tailored to the application.
Practical Issues with Formal Specifications
NASA Astrophysics Data System (ADS)
Altenhofen, Michael; Brucker, Achim D.
Many software companies still seem to be reluctant to use formal specifications in their development processes. Nevertheless, the trend towards implementing critical business applications in distributed environments makes such applications an attractive target for formal methods. Additionally, the rising complexity also increases the willingness of the development teams to apply formal techniques.
Covariant Bardeen perturbation formalism
NASA Astrophysics Data System (ADS)
Vitenti, S. D. P.; Falciano, F. T.; Pinto-Neto, N.
2014-05-01
In a previous work we obtained a set of necessary conditions for the linear approximation in cosmology. Here we discuss the relations of this approach with the so-called covariant perturbations. It is often argued in the literature that one of the main advantages of the covariant approach to describe cosmological perturbations is that the Bardeen formalism is coordinate dependent. In this paper we will reformulate the Bardeen approach in a completely covariant manner. For that, we introduce the notion of pure and mixed tensors, which yields an adequate language to treat both perturbative approaches in a common framework. We then stress that in the referred covariant approach, one necessarily introduces an additional hypersurface choice to the problem. Using our mixed and pure tensors approach, we are able to construct a one-to-one map relating the usual gauge dependence of the Bardeen formalism with the hypersurface dependence inherent to the covariant approach. Finally, through the use of this map, we define full nonlinear tensors that at first order correspond to the three known gauge invariant variables Φ, Ψ and Ξ, which are simultaneously foliation and gauge invariant. We then stress that the use of the proposed mixed tensors allows one to construct simultaneously gauge and hypersurface invariant variables at any order.
Hamiltonian formalism of minimal massive gravity
NASA Astrophysics Data System (ADS)
Mahdavian Yekta, Davood
2015-09-01
In this paper, we study the three-dimensional minimal massive gravity (MMG) in the Hamiltonian formalism. At first, we define the canonical gauge generators as building blocks in this formalism and then derive the canonical expressions for the asymptotic conserved charges. The construction of a consistent asymptotic structure of MMG requires introducing suitable boundary conditions. In the second step, we show that the Poisson bracket algebra of the improved canonical gauge generators produces an asymptotic gauge group, which includes two separable versions of the Virasoro algebras. For instance, we study the Banados-Teitelboim-Zanelli (BTZ) black hole as a solution of the MMG field equations, and the conserved charges give the energy and angular momentum of the BTZ black hole. Finally, we compute the black hole entropy from the Cardy formula in the dual conformal field theory and show our result is consistent with the value obtained by using the Smarr formula from the holographic principle.
The formal verification of generic interpreters
NASA Technical Reports Server (NTRS)
Windley, P.; Levitt, K.; Cohen, G. C.
1991-01-01
The task assignment 3 of the design and validation of digital flight control systems suitable for fly-by-wire applications is studied. Task 3 is associated with formal verification of embedded systems. In particular, results are presented that provide a methodological approach to microprocessor verification. A hierarchical decomposition strategy for specifying microprocessors is also presented. A theory of generic interpreters is presented that can be used to model microprocessor behavior. The generic interpreter theory abstracts away the details of instruction functionality, leaving a general model of what an interpreter does.
Hamilton-Jacobi formalism for tachyon inflation
NASA Astrophysics Data System (ADS)
Aghamohammadi, A.; Mohammadi, A.; Golanbari, T.; Saaidi, Kh.
2014-10-01
Tachyon inflation is reconsidered by using the recent observational data obtained from Planck-2013 and BICEP2. The Hamilton-Jacobi formalism is picked out as a desirable approach in this work, which allows one to easily obtain the main parameters of the model. The Hubble parameter is supposed as a power-law and exponential function of the scalar field, and each case is considered separately. The constraints on the model, which come from observational data, are explained during the work. The results show a suitable value for the tensor spectral index and an appropriate form of the potential.
Formal verification of AI software
NASA Technical Reports Server (NTRS)
Rushby, John; Whitehurst, R. Alan
1989-01-01
The application of formal verification techniques to Artificial Intelligence (AI) software, particularly expert systems, is investigated. Constraint satisfaction and model inversion are identified as two formal specification paradigms for different classes of expert systems. A formal definition of consistency is developed, and the notion of approximate semantics is introduced. Examples are given of how these ideas can be applied in both declarative and imperative forms.
Formalized Epistemology, Logic, and Grammar
NASA Astrophysics Data System (ADS)
Bitbol, Michel
The task of a formal epistemology is defined. It appears that a formal epistemology must be a generalization of "logic" in the sense of Wittgenstein's Tractatus. The generalization is required because, whereas logic presupposes a strict relation between activity and language, this relation may be broken in some domains of experimental enquiry (e.g., in microscopic physics). However, a formal epistemology should also retain a major feature of Wittgenstein's "logic": It must not be a discourse about scientific knowledge, but rather a way of making manifest the structures usually implicit in knowledge-gaining activity. This strategy is applied to the formalism of quantum mechanics.
Formal, Non-Formal and Informal Learning in the Sciences
ERIC Educational Resources Information Center
Ainsworth, Heather L.; Eaton, Sarah Elaine
2010-01-01
This research report investigates the links between formal, non-formal and informal learning and the differences between them. In particular, the report aims to link these notions of learning to the field of sciences and engineering in Canada and the United States, including professional development of adults working in these fields. It offers…
NASA Astrophysics Data System (ADS)
Hamaya, S.; Maeda, H.; Funaki, M.; Fukui, H.
2008-12-01
The relativistic calculation of nuclear magnetic shielding tensors in hydrogen halides is performed using the second-order regular approximation to the normalized elimination of the small component (SORA-NESC) method with the inclusion of the perturbation terms from the metric operator. This computational scheme is denoted as SORA-Met. The SORA-Met calculation yields anisotropies, Δσ =σ∥-σ⊥, for the halogen nuclei in hydrogen halides that are too small. In the NESC theory, the small component of the spinor is combined to the large component via the operator σ⃗ṡπ⃗U/2c, in which π⃗=p⃗+A⃗, U is a nonunitary transformation operator, and c ≅137.036 a.u. is the velocity of light. The operator U depends on the vector potential A⃗ (i.e., the magnetic perturbations in the system) with the leading order c-2 and the magnetic perturbation terms of U contribute to the Hamiltonian and metric operators of the system in the leading order c-4. It is shown that the small Δσ for halogen nuclei found in our previous studies is related to the neglect of the U(0,1) perturbation operator of U, which is independent of the external magnetic field and of the first order with respect to the nuclear magnetic dipole moment. Introduction of gauge-including atomic orbitals and a finite-size nuclear model is also discussed.
Hamaya, S; Maeda, H; Funaki, M; Fukui, H
2008-12-14
The relativistic calculation of nuclear magnetic shielding tensors in hydrogen halides is performed using the second-order regular approximation to the normalized elimination of the small component (SORA-NESC) method with the inclusion of the perturbation terms from the metric operator. This computational scheme is denoted as SORA-Met. The SORA-Met calculation yields anisotropies, Delta sigma = sigma(parallel) - sigma(perpendicular), for the halogen nuclei in hydrogen halides that are too small. In the NESC theory, the small component of the spinor is combined to the large component via the operator sigma x piU/2c, in which pi = p + A, U is a nonunitary transformation operator, and c approximately = 137.036 a.u. is the velocity of light. The operator U depends on the vector potential A (i.e., the magnetic perturbations in the system) with the leading order c(-2) and the magnetic perturbation terms of U contribute to the Hamiltonian and metric operators of the system in the leading order c(-4). It is shown that the small Delta sigma for halogen nuclei found in our previous studies is related to the neglect of the U(0,1) perturbation operator of U, which is independent of the external magnetic field and of the first order with respect to the nuclear magnetic dipole moment. Introduction of gauge-including atomic orbitals and a finite-size nuclear model is also discussed.
Scalar heat kernel with boundary in the worldline formalism
NASA Astrophysics Data System (ADS)
Bastianelli, Fiorenzo; Corradini, Olindo; Pisani, Pablo A. G.; Schubert, Christian
2008-10-01
The worldline formalism has in recent years emerged as a powerful tool for the computation of effective actions and heat kernels. However, implementing nontrivial boundary conditions in this formalism has turned out to be a difficult problem. Recently, such a generalization was developed for the case of a scalar field on the half-space Bbb R+ × Bbb RD-1, based on an extension of the associated worldline path integral to the full Bbb RD using image charges. We present here an improved version of this formalism which allows us to write down non-recursive master formulas for the n-point contribution to the heat kernel trace of a scalar field on the half-space with Dirichlet or Neumann boundary conditions. These master formulas are suitable to computerization. We demonstrate the efficiency of the formalism by a calculation of two new heat-kernel coefficients for the half-space, a4 and a9/2.
NASA Formal Methods Workshop, 1990
NASA Technical Reports Server (NTRS)
Butler, Ricky W. (Compiler)
1990-01-01
The workshop brought together researchers involved in the NASA formal methods research effort for detailed technical interchange and provided a mechanism for interaction with representatives from the FAA and the aerospace industry. The workshop also included speakers from industry to debrief the formal methods researchers on the current state of practice in flight critical system design, verification, and certification. The goals were: define and characterize the verification problem for ultra-reliable life critical flight control systems and the current state of practice in industry today; determine the proper role of formal methods in addressing these problems, and assess the state of the art and recent progress toward applying formal methods to this area.
Formalism and functionalism in linguistics.
Newmeyer, Frederick J
2010-05-01
Formalism and functionalism in linguistics are often taken to be diametrically opposed approaches. However, close examination of the relevant phenomena reveals that the two are complementary, rather than being irrevocably in opposition to each other. One can be a formal linguist and a functional linguist at the same time, without there being any contradiction. Copyright © 2010 John Wiley & Sons, Ltd. For further resources related to this article, please visit the WIREs website.
Ultrafast charge transfer and atomic orbital polarization
Deppe, M.; Foehlisch, A.; Hennies, F.; Nagasono, M.; Beye, M.; Sanchez-Portal, D.; Echenique, P. M.; Wurth, W.
2007-11-07
The role of orbital polarization for ultrafast charge transfer between an atomic adsorbate and a substrate is explored. Core hole clock spectroscopy with linearly polarized x-ray radiation allows to selectively excite adsorbate resonance states with defined spatial orientation relative to the substrate surface. For c(4x2)S/Ru(0001) the charge transfer times between the sulfur 2s{sup -1}3p*{sup +1} antibonding resonance and the ruthenium substrate have been studied, with the 2s electron excited into the 3p{sub perpendicular}* state along the surface normal and the 3p{sub parallel}* state in the surface plane. The charge transfer times are determined as 0.18{+-}0.07 and 0.84{+-}0.23 fs, respectively. This variation is the direct consequence of the different adsorbate-substrate orbital overlap.
Formalization of an environmental model using formal concept analysis - FCA
NASA Astrophysics Data System (ADS)
Bourdon-García, Rubén D.; Burgos-Salcedo, Javier D.
2016-08-01
Nowadays, there is a huge necessity to generate novel strategies for social-ecological systems analyses for resolving global sustainability problems. This paper has as main purpose the application of the formal concept analysis to formalize the theory of Augusto Ángel Maya, who without a doubt, was one of the most important environmental philosophers in South America; Ángel Maya proposed and established that Ecosystem-Culture relations, instead Human-Nature ones, are determinants in our understanding and management of natural resources. Based on this, a concept lattice, formal concepts, subconcept-superconcept relations, partially ordered sets, supremum and infimum of the lattice and implications between attributes (Duquenne-Guigues base), were determined for the ecosystem-culture relations.
Generalized Boltzmann formalism for oscillating neutrinos
Strack, P.; Burrows, A.
2005-05-01
In the standard approaches to neutrino transport in the simulation of core-collapse supernovas, one will often start from the classical Boltzmann equation for the neutrino's spatial, temporal, and spectral evolution. For each neutrino species, and its antiparticle, the classical density in phase space, or the associated specific intensity, will be calculated as a function of time. The neutrino radiation is coupled to matter by source and sink terms on the 'right-hand side' of the transport equation and together with the equations of hydrodynamics this set of coupled partial differential equations for classical densities describes, in principle, the evolution of core collapse and explosion. However, with the possibility of neutrino oscillations between species, a purely quantum-physical effect, how to generalize this set of Boltzmann equations for classical quantities to reflect oscillation physics has not been clear. To date, the formalisms developed have retained the character of quantum operator physics involving complex quantities and have not been suitable for easy incorporation into standard supernova codes. In this paper, we derive generalized Boltzmann equations for quasiclassical, real-valued phase-space densities that retain all the standard oscillation phenomenology, including the matter-enhanced resonant flavor conversion (Mikheev-Smirnov-Wolfenstein effect), neutrino self-interactions, and the interplay between decohering matter coupling and flavor oscillations. With this formalism, any code(s) that can now handle the solution of the classical Boltzmann or transport equation can easily be generalized to include neutrino oscillations in a quantum-physically consistent fashion.
Modeling formalisms in Systems Biology
2011-01-01
Systems Biology has taken advantage of computational tools and high-throughput experimental data to model several biological processes. These include signaling, gene regulatory, and metabolic networks. However, most of these models are specific to each kind of network. Their interconnection demands a whole-cell modeling framework for a complete understanding of cellular systems. We describe the features required by an integrated framework for modeling, analyzing and simulating biological processes, and review several modeling formalisms that have been used in Systems Biology including Boolean networks, Bayesian networks, Petri nets, process algebras, constraint-based models, differential equations, rule-based models, interacting state machines, cellular automata, and agent-based models. We compare the features provided by different formalisms, and discuss recent approaches in the integration of these formalisms, as well as possible directions for the future. PMID:22141422
NASA Technical Reports Server (NTRS)
Owre, Sam; Shankar, Natarajan
1999-01-01
A specification language is a medium for expressing what is computed rather than how it is computed. Specification languages share some features with programming languages but are also different in several important ways. For our purpose, a specification language is a logic within which the behavior of computational systems can be formalized. Although a specification can be used to simulate the behavior of such systems, we mainly use specifications to state and prove system properties with mechanical assistance. We present the formal semantics of the specification language of SRI's Prototype Verification System (PVS). This specification language is based on the simply typed lambda calculus. The novelty in PVS is that it contains very expressive language features whose static analysis (e.g., typechecking) requires the assistance of a theorem prover. The formal semantics illuminates several of the design considerations underlying PVS, the interaction between theorem proving and typechecking.
Modeling formalisms in Systems Biology.
Machado, Daniel; Costa, Rafael S; Rocha, Miguel; Ferreira, Eugénio C; Tidor, Bruce; Rocha, Isabel
2011-01-01
Systems Biology has taken advantage of computational tools and high-throughput experimental data to model several biological processes. These include signaling, gene regulatory, and metabolic networks. However, most of these models are specific to each kind of network. Their interconnection demands a whole-cell modeling framework for a complete understanding of cellular systems. We describe the features required by an integrated framework for modeling, analyzing and simulating biological processes, and review several modeling formalisms that have been used in Systems Biology including Boolean networks, Bayesian networks, Petri nets, process algebras, constraint-based models, differential equations, rule-based models, interacting state machines, cellular automata, and agent-based models. We compare the features provided by different formalisms, and discuss recent approaches in the integration of these formalisms, as well as possible directions for the future. PMID:22141422
Formal verification of mathematical software
NASA Technical Reports Server (NTRS)
Sutherland, D.
1984-01-01
Methods are investigated for formally specifying and verifying the correctness of mathematical software (software which uses floating point numbers and arithmetic). Previous work in the field was reviewed. A new model of floating point arithmetic called the asymptotic paradigm was developed and formalized. Two different conceptual approaches to program verification, the classical Verification Condition approach and the more recently developed Programming Logic approach, were adapted to use the asymptotic paradigm. These approaches were then used to verify several programs; the programs chosen were simplified versions of actual mathematical software.
Evidence Arguments for Using Formal Methods in Software Certification
NASA Technical Reports Server (NTRS)
Denney, Ewen W.; Pai, Ganesh
2013-01-01
We describe a generic approach for automatically integrating the output generated from a formal method/tool into a software safety assurance case, as an evidence argument, by (a) encoding the underlying reasoning as a safety case pattern, and (b) instantiating it using the data produced from the method/tool. We believe this approach not only improves the trustworthiness of the evidence generated from a formal method/tool, by explicitly presenting the reasoning and mechanisms underlying its genesis, but also provides a way to gauge the suitability of the evidence in the context of the wider assurance case. We illustrate our work by application to a real example-an unmanned aircraft system- where we invoke a formal code analysis tool from its autopilot software safety case, automatically transform the verification output into an evidence argument, and then integrate it into the former.
A brief overview of NASA Langley's research program in formal methods
NASA Technical Reports Server (NTRS)
1992-01-01
An overview of NASA Langley's research program in formal methods is presented. The major goal of this work is to bring formal methods technology to a sufficiently mature level for use by the United States aerospace industry. Towards this goal, work is underway to design and formally verify a fault-tolerant computing platform suitable for advanced flight control applications. Also, several direct technology transfer efforts have been initiated that apply formal methods to critical subsystems of real aerospace computer systems. The research team consists of six NASA civil servants and contractors from Boeing Military Aircraft Company, Computational Logic Inc., Odyssey Research Associates, SRI International, University of California at Davis, and Vigyan Inc.
The Traps of Formal Correspondence.
ERIC Educational Resources Information Center
Albert, Sandor
The dangers of translation are discussed when the translator does not try to create textual equivalence, but settles for formal correspondence (i.e., with simple transcoding at a linguistic level) during the process of translating. Difficulties of explaining, commenting, or summarizing rather than translating are also discussed. Pedagogical and…
Habitat Suitability Index Models: Pronghorn
Allen, Arthur W.; Cook, John G.; Armbruster, Michael J.
1984-01-01
This is one of a series of publications that provide information on the habitat requirements of selected fish and wildlife species. Literature describing the relationship between habitat variables related to life requisites and habitat suitability for the pronghorn (Antilocapra americana) are synthesized. These data are subsequently used to develop Habitat Suitability Index (HSI) models. The HSI models are designed to provide information that can be used in impact assessment and habitat management.
Formal Analysis of Message Passing
NASA Astrophysics Data System (ADS)
Siegel, Stephen F.; Gopalakrishnan, Ganesh
The message passing paradigm underlies many important families of programs - for instance programs in the area of high performance computing that support science and engineering research. Unfortunately, very few formal methods researchers are involved in developing formal analysis tools and techniques for message passing programs. This paper summarizes research being done in our groups in support of this area, specifically with respect to the Message Passing Interface. We emphasize the need for specialized varieties of many familiar notions such as deadlock detection, race analysis, symmetry analysis, partial order reduction, static analysis and symbolic reasoning support. Since these issues are harbingers of those being faced in multicore programming, the time is ripe to build a critical mass of researchers working in this area.
Formalizing narratives using nested circumscription
Baral, C.; Gabaldon, A.; Provetti, A.
1996-12-31
The representation of narratives of actions and observations is a current issue in Knowledge Representation, where traditional plan-oriented treatments of action seem to fall short. To address narratives, Pinto and Reiter have extended Situation Calculus axioms, Kowalski and Sergot have introduced the Event Calculus in Logic Programming, and Baral et al. have defined the specification language L which allows to express actual and hypothetical situations in a uniform setting. The L entailment relation can formalize several forms of reasoning about actions and change. In this paper we illustrate a translation of L theories into Nested Abnormality Theories, a novel form of circumscription. The proof of soundness and completeness of the translation is the main technical result of the paper, but attention is also devoted to the features of Nested Abnormality Theories to capture commonsense reasoning in general and to clarify which assumptions a logical formalization forces upon a domain. These results also help clarifying the relationship between L and other recent circumscriptive formalization for narratives, such as Miller and Shanahan`s.
Habitat Suitability Index Models: Marten
Allen, Arthur W.
1982-01-01
Habitat preferences and species characteristics of the pine marten (Martes americana) are described in this publication. It is one of a series of Habitat Suitability Index (HSI) models and was developed through an analysis of available scientific data on the species-habitat requirements of the pine marten. Habitat use information is presented in a review of the literature, followed by the development of a HSI model. The model is presented in three formats: graphic, word and mathematical. Suitability index graphs quantify the species-habitat relationship. These data are then synthesized into a model which is designed to provide information for use in impact assessment and habitat management activities.
Habitat Suitability Index Models: Veery
Sousa, Patrick J.
1982-01-01
Habitat preferences and species characteristics of the veery (Catharus fuscesens) are described in this publication. It is one of a series of Habitat Suitability Index (HSI) models and was developed through an analysis of available scientific data on the habitat requirements of the veery. Habitat use information is presented in a review of the literature, followed by the development of an HSI model. The model is presented in three formats: graphic; word; and mathematical. Suitability index graphs quantify the species-habitat relationship. These data are synthesized into a model designed to provide information for use in impact assessment and habitat management.
Asymmetric Formal Synthesis of Azadirachtin.
Mori, Naoki; Kitahara, Takeshi; Mori, Kenji; Watanabe, Hidenori
2015-12-01
An asymmetric formal synthesis of azadirachtin, a potent insect antifeedant, was accomplished in 30 steps to Ley's synthetic intermediate (longest linear sequence). The synthesis features: 1) rapid access to the optically active right-hand segment starting from the known 5-hydroxymethyl-2-cyclopentenone scaffold; 2) construction of the B and E rings by a key intramolecular tandem radical cyclization; 3) formation of the hemiacetal moiety in the C ring through the α-oxidation of the six-membered lactone followed by methanolysis. PMID:26474211
Knowledge formalization of intelligent building
NASA Astrophysics Data System (ADS)
Žáček, Martin
2016-06-01
This article aim is understanding the basic knowledge about an intelligent building. The notion of the intelligent building can be called any building equipped with computer and communication technology, which can automatically respond to internal or external stimuli. The result of the intelligent building is an automated and foreseeing of activities that enable to reduce operating costs and increase comfort. The best way to use the intelligent building is for a low-energy building, a passive building, or for building with high savings. The output of this article is the formalization of basic knowledge of the intelligent building by RDF graph.
NASA Astrophysics Data System (ADS)
Zharinov, V. V.
2013-02-01
We propose a formal construction generalizing the classic de Rham complex to a wide class of models in mathematical physics and analysis. The presentation is divided into a sequence of definitions and elementary, easily verified statements; proofs are therefore given only in the key case. Linear operations are everywhere performed over a fixed number field {F} = {R},{C}. All linear spaces, algebras, and modules, although not stipulated explicitly, are by definition or by construction endowed with natural locally convex topologies, and their morphisms are continuous.
47 CFR 8.12 - Formal complaints.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 47 Telecommunication 1 2013-10-01 2013-10-01 false Formal complaints. 8.12 Section 8.12 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRESERVING THE OPEN INTERNET § 8.12 Formal complaints. Any person may file a formal complaint alleging a violation of the rules in this part....
47 CFR 8.12 - Formal complaints.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 47 Telecommunication 1 2014-10-01 2014-10-01 false Formal complaints. 8.12 Section 8.12 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRESERVING THE OPEN INTERNET § 8.12 Formal complaints. Any person may file a formal complaint alleging a violation of the rules in this part....
47 CFR 8.12 - Formal Complaints.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 47 Telecommunication 1 2011-10-01 2011-10-01 false Formal Complaints. 8.12 Section 8.12 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRESERVING THE OPEN INTERNET § 8.12 Formal Complaints. Any person may file a formal complaint alleging a violation of the rules in this part....
47 CFR 8.12 - Formal complaints.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 47 Telecommunication 1 2012-10-01 2012-10-01 false Formal complaints. 8.12 Section 8.12 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRESERVING THE OPEN INTERNET § 8.12 Formal complaints. Any person may file a formal complaint alleging a violation of the rules in this part....
Formal apparatus of soil classification
NASA Astrophysics Data System (ADS)
Rozhkov, V. A.
2011-12-01
Mathematical tools that may be applied for soil classification purposes are discussed. They include the evaluation of information contained in particular soil attributes, the grouping of soil objects into a given (automatically determined) number of classes, the optimization of the classification decisions, and the development of the models and rules (algorithms) used to classify soil objects. The algorithms of multivariate statistical methods and cluster analysis used for solving these problems are described. The major attention is paid to the development of the systems of informative attributes of soil objects and their classes and to the assessment of the quality of the classification decisions. Particular examples of the solution of the problems of soil classification with the use of formal mathematical methods are given. It is argued that the theoretical and practical problems of classification in science cannot find objective solutions without the application of the modern methods of information analysis. The major problems of the numerical taxonomy of the soil objects described in this paper and the appropriate software tools for their solution should serve as the basis for the creation of not only formal soil classification systems but also the theory of soil classification.
A Formal Approach to Domain-Oriented Software Design Environments
NASA Technical Reports Server (NTRS)
Lowry, Michael; Philpot, Andrew; Pressburger, Thomas; Underwood, Ian; Lum, Henry, Jr. (Technical Monitor)
1994-01-01
This paper describes a formal approach to domain-oriented software design environments, based on declarative domain theories, formal specifications, and deductive program synthesis. A declarative domain theory defines the semantics of a domain-oriented specification language and its relationship to implementation-level subroutines. Formal specification development and reuse is made accessible to end-users through an intuitive graphical interface that guides them in creating diagrams denoting formal specifications. The diagrams also serve to document the specifications. Deductive program synthesis ensures that end-user specifications are correctly implemented. AMPHION has been applied to the domain of solar system kinematics through the development of a declarative domain theory, which includes an axiomatization of JPL's SPICELIB subroutine library. Testing over six months with planetary scientists indicates that AMPHION's interactive specification acquisition paradigm enables users to develop, modify, and reuse specifications at least an order of magnitude more rapidly than manual program development. Furthermore, AMPHION synthesizes one to two page programs consisting of calls to SPICELIB subroutines from these specifications in just a few minutes. Test results obtained by metering AMPHION's deductive program synthesis component are examined. AMPHION has been installed at JPL and is currently undergoing further refinement in preparation for distribution to hundreds of SPICELIB users worldwide. Current work to support end-user customization of AMPHION's specification acquisition subsystem is briefly discussed, as well as future work to enable domain-expert creation of new AMPHION applications through development of suitable domain theories.
Habitat Suitability Index Models: Muskellunge
Cook, Mark F.; Solomon, R. Charles
1987-01-01
A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the muskellunge (Esox masquinongy Mitchell). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
Habitat Suitability Index Models: Bobcat
Boyle, Katherine A.; Fendley, Timothy T.
1987-01-01
A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the bobcat (Felis rufus). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
Formal Methods at Intel - An Overview
NASA Technical Reports Server (NTRS)
Harrison, John
2010-01-01
Since the 1990s, Intel has invested heavily in formal methods, which are now deployed in several domains: hardware, software, firmware, protocols etc. Many different formal methods tools and techniques are in active use, including symbolic trajectory evaluation, temporal logic model checking, SMT-style combined decision procedures, and interactive higher-order logic theorem proving. I will try to give a broad overview of some of the formal methods activities taking place at Intel, and describe the challenges of extending formal verification to new areas and of effectively using multiple formal techniques in combination
Formal methods technology transfer: Some lessons learned
NASA Technical Reports Server (NTRS)
Hamilton, David
1992-01-01
IBM has a long history in the application of formal methods to software development and verification. There have been many successes in the development of methods, tools and training to support formal methods. And formal methods have been very successful on several projects. However, the use of formal methods has not been as widespread as hoped. This presentation summarizes several approaches that have been taken to encourage more widespread use of formal methods, and discusses the results so far. The basic problem is one of technology transfer, which is a very difficult problem. It is even more difficult for formal methods. General problems of technology transfer, especially the transfer of formal methods technology, are also discussed. Finally, some prospects for the future are mentioned.
ERIC Educational Resources Information Center
Schwier, Richard A.; Seaton, J. X.
2013-01-01
Does learner participation vary depending on the learning context? Are there characteristic features of participation evident in formal, non-formal, and informal online learning environments? Six online learning environments were chosen as epitomes of formal, non-formal, and informal learning contexts and compared. Transcripts of online…
Matrix Formalism of Synchrobetatron Coupling
Huang, Xiaobiao; /SLAC
2006-10-06
In this paper we present a complete linear synchrobetatron coupling formalism by studying the transfer matrix which describes linear horizontal and longitudinal motions. With the technique established in the linear horizontal-vertical coupling study [D. Sagan and D. Rubin, Phys. Rev. ST Accel. Beams 2, 074001 (1999)], we found a transformation to block diagonalize the transfer matrix and decouple the betatron motion and the synchrotron motion. By separating the usual dispersion term from the horizontal coordinate first, we were able to obtain analytic expressions of the transformation under reasonable approximations. We also obtained the perturbations to the betatron tune and the Courant-Snyder functions. The closed orbit changes due to finite energy gains at rf cavities and radiation energy losses were also studied by the 5 x 5 extended transfer matrix with the fifth column describing kicks in the 4-dimension phase space.
Formal modeling of virtual machines
NASA Technical Reports Server (NTRS)
Cremers, A. B.; Hibbard, T. N.
1978-01-01
Systematic software design can be based on the development of a 'hierarchy of virtual machines', each representing a 'level of abstraction' of the design process. The reported investigation presents the concept of 'data space' as a formal model for virtual machines. The presented model of a data space combines the notions of data type and mathematical machine to express the close interaction between data and control structures which takes place in a virtual machine. One of the main objectives of the investigation is to show that control-independent data type implementation is only of limited usefulness as an isolated tool of program development, and that the representation of data is generally dictated by the control context of a virtual machine. As a second objective, a better understanding is to be developed of virtual machine state structures than was heretofore provided by the view of the state space as a Cartesian product.
Formal analysis of electromagnetic optics
NASA Astrophysics Data System (ADS)
Khan-Afshar, Sanaz; Hasan, Osman; Tahar, Sofiène
2014-09-01
Optical systems are increasingly being used in safety-critical applications. Due to the complexity and sensitivity of optical systems, their verification raises many challenges for engineers. Traditionally, the analysis of such systems has been carried out by paper-and-pencil based proofs and numerical computations. However, these techniques cannot provide accurate results due to the risk of human error and inherent approximations of numerical algorithms. In order to overcome these limitations, we propose to use theorem proving (i.e., a computer-based technique that allows to express mathematical expressions and reason about their correctness by taking into account all the details of mathematical reasoning) as a complementary approach to improve optical system analysis. This paper provides a higher-order logic (a language used to express mathematical theories) formalization of electromagnetic optics in the HOL Light theorem prover. In order to demonstrate the practical effectiveness of our approach, we present the analysis of resonant cavity enhanced photonic devices.
Two-state vector formalism and quantum interference
NASA Astrophysics Data System (ADS)
Hashmi, F. A.; Li, Fu; Zhu, Shi-Yao; Zubairy, M. Suhail
2016-08-01
We show that two-state vector formalism (TSVF), applied to quantum systems that make use of delicate interference effects, can lead to paradoxes. We consider a few schemes of nested Mach–Zehnder interferometers that make use of destructive interference. A particular interpretation of TSVF applied to these schemes makes predictions that are contradictory to quantum theory and can not always be verified. Our results suggest that TSVF might not be a suitable tool to describe quantum systems that make use of delicate quantum interference effects.
Two-state vector formalism and quantum interference
NASA Astrophysics Data System (ADS)
Hashmi, F. A.; Li, Fu; Zhu, Shi-Yao; Zubairy, M. Suhail
2016-08-01
We show that two-state vector formalism (TSVF), applied to quantum systems that make use of delicate interference effects, can lead to paradoxes. We consider a few schemes of nested Mach-Zehnder interferometers that make use of destructive interference. A particular interpretation of TSVF applied to these schemes makes predictions that are contradictory to quantum theory and can not always be verified. Our results suggest that TSVF might not be a suitable tool to describe quantum systems that make use of delicate quantum interference effects.
Formal and informal authority of hospital directors.
Nirel, N; Schmid, H; Stern, Z
1994-01-01
Describes and contrasts the perceptions of formal and informal authority of hospital directors of two different kinds of organizations: hospitals that are part of public multi-hospital organizations (PMOs) and independent hospitals. Indicates that all the directors perceive their formal authority to be greater than their formal authority. However, there is a gap in the perception of formal and informal authority by directors of the two types of hospital. Directors of independent hospitals perceive themselves to have more formal and informal authority than do their colleagues at hospitals that are part of PMOs. Both structural and personal explanations for these findings are given. In addition, discusses the implications for policy making of the source of authority, informal, and formal authority in the transition to autonomous semi-independent hospitals in a changing environment.
Anyons in the operational formalism
NASA Astrophysics Data System (ADS)
Neori, Klil H.; Goyal, Philip
2015-01-01
The operational formalism to quantum mechanics seeks to base the theory on a firm foundation of physically well-motivated axioms [1]. It has succeeded in deriving the Feynman rules [2] for general quantum systems. Additional elaborations have applied the same logic to the question of identical particles, confirming the so-called Symmetrization Postulate [3]: that the only two options available are fermions and bosons [4, 5]. However, this seems to run counter to results in two-dimensional systems, which allow for anyons, particles with statistics which interpolate between Fermi-Dirac and Bose-Einstein (see [6] for a review). In this talk we will show that the results in two dimensions can be made compatible with the operational results. That is, we will show that anyonic behavior is a result of the topology of the space in two dimensions [7], and does not depend on the particles being identical; but that nevertheless, if the particles are identical, the resulting system is still anyonic.
Universal formalism of Fano resonance
Huang, Liang; Lai, Ying-Cheng; Luo, Hong-Gang; Grebogi, Celso
2015-01-15
The phenomenon of Fano resonance is ubiquitous in a large variety of wave scattering systems, where the resonance profile is typically asymmetric. Whether the parameter characterizing the asymmetry should be complex or real is an issue of great experimental interest. Using coherent quantum transport as a paradigm and taking into account of the collective contribution from all available scattering channels, we derive a universal formula for the Fano-resonance profile. We show that our formula bridges naturally the traditional Fano formulas with complex and real asymmetry parameters, indicating that the two types of formulas are fundamentally equivalent (except for an offset). The connection also reveals a clear footprint for the conductance resonance during a dephasing process. Therefore, the emergence of complex asymmetric parameter when fitting with experimental data needs to be properly interpreted. Furthermore, we have provided a theory for the width of the resonance, which relates explicitly the width to the degree of localization of the close-by eigenstates and the corresponding coupling matrices or the self-energies caused by the leads. Our work not only resolves the issue about the nature of the asymmetry parameter, but also provides deeper physical insights into the origin of Fano resonance. Since the only assumption in our treatment is that the transport can be described by the Green’s function formalism, our results are also valid for broad disciplines including scattering problems of electromagnetic waves, acoustics, and seismology.
Anyons in the operational formalism
Neori, Klil H.; Goyal, Philip
2015-01-13
The operational formalism to quantum mechanics seeks to base the theory on a firm foundation of physically well-motivated axioms [1]. It has succeeded in deriving the Feynman rules [2] for general quantum systems. Additional elaborations have applied the same logic to the question of identical particles, confirming the so-called Symmetrization Postulate [3]: that the only two options available are fermions and bosons [4, 5]. However, this seems to run counter to results in two-dimensional systems, which allow for anyons, particles with statistics which interpolate between Fermi-Dirac and Bose-Einstein (see [6] for a review). In this talk we will show that the results in two dimensions can be made compatible with the operational results. That is, we will show that anyonic behavior is a result of the topology of the space in two dimensions [7], and does not depend on the particles being identical; but that nevertheless, if the particles are identical, the resulting system is still anyonic.
Survey of Existing Tools for Formal Verification.
Punnoose, Ratish J.; Armstrong, Robert C.; Wong, Matthew H.; Jackson, Mayo
2014-12-01
Formal methods have come into wide use because of their effectiveness in verifying "safety and security" requirements of digital systems; a set of requirements for which testing is mostly ineffective. Formal methods are routinely used in the design and verification of high-consequence digital systems in industry. This report outlines our work in assessing the capabilities of commercial and open source formal tools and the ways in which they can be leveraged in digital design workflows.
Formalization of algorithms for relational database machines
Ryvkin, V.M.; Komarov, P.I.; Nazarov, A.S.
1986-11-01
This paper applies the apparatus of algorithmic algebras to formalize the mapping of the relational algebra language into the internal database processor language. The apparatus is a popular tool for formal structured description of parallel algorithms. The MUL'TIPROTSESSIST automatic parallel program design system using systems of algorithmic algebras may be applied to automate the design of database machine operating algorithms in experimental research and to formalize the parallel organization of interpretation algorithms for the relational algebraic operations.
Identification of process suitable diluent
Dean R. Peterman
2014-01-01
The Sigma Team for Minor Actinide Separation (STMAS) was formed within the USDOE Fuel Cycle Research and Development (FCRD) program in order to develop more efficient methods for the separation of americium and other minor actinides (MA) from used nuclear fuel. The development of processes for MA separations is driven by the potential benefits; reduced long-term radiotoxicty of waste placed in a geologic repository, reduced timeframe of waste storage, reduced repository heat load, the possibility of increased repository capacity, and increased utilization of energy potential of used nuclear fuel. The research conducted within the STMAS framework is focused upon the realization of significant simplifications to aqueous recycle processes proposed for MA separations. This report describes the research efforts focused upon the identification of a process suitable diluent for a flowsheet concept for the separation of MA which is based upon the dithiophosphinic acid (DPAH) extractants previously developed at the Idaho National Laboratory (INL).
Third NASA Langley Formal Methods Workshop
NASA Technical Reports Server (NTRS)
Holloway, C. Michael (Compiler)
1995-01-01
This publication constitutes the proceedings of NASA Langley Research Center's third workshop on the application of formal methods to the design and verification of life-critical systems. This workshop brought together formal methods researchers, industry engineers, and academicians to discuss the potential of NASA-sponsored formal methods and to investigate new opportunities for applying these methods to industry problems. contained herein are copies of the material presented at the workshop, summaries of many of the presentations, a complete list of attendees, and a detailed summary of the Langley formal methods program. Much of this material is available electronically through the World-Wide Web via the following URL.
Formal Methods for Life-Critical Software
NASA Technical Reports Server (NTRS)
Butler, Ricky W.; Johnson, Sally C.
1993-01-01
The use of computer software in life-critical applications, such as for civil air transports, demands the use of rigorous formal mathematical verification procedures. This paper demonstrates how to apply formal methods to the development and verification of software by leading the reader step-by-step through requirements analysis, design, implementation, and verification of an electronic phone book application. The current maturity and limitations of formal methods tools and techniques are then discussed, and a number of examples of the successful use of formal methods by industry are cited.
The Second NASA Formal Methods Workshop 1992
NASA Technical Reports Server (NTRS)
Johnson, Sally C. (Compiler); Holloway, C. Michael (Compiler); Butler, Ricky W. (Compiler)
1992-01-01
The primary goal of the workshop was to bring together formal methods researchers and aerospace industry engineers to investigate new opportunities for applying formal methods to aerospace problems. The first part of the workshop was tutorial in nature. The second part of the workshop explored the potential of formal methods to address current aerospace design and verification problems. The third part of the workshop involved on-line demonstrations of state-of-the-art formal verification tools. Also, a detailed survey was filled in by the attendees; the results of the survey are compiled.
10 CFR 963.11 - Suitability determination.
Code of Federal Regulations, 2013 CFR
2013-01-01
... DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability Determination, Methods, and Criteria § 963.11 Suitability determination. DOE will evaluate whether the Yucca Mountain site is suitable... determinations described in §§ 963.12 and 963.15. If DOE's evaluation of the Yucca Mountain site for the...
10 CFR 963.11 - Suitability determination.
Code of Federal Regulations, 2014 CFR
2014-01-01
... DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability Determination, Methods, and Criteria § 963.11 Suitability determination. DOE will evaluate whether the Yucca Mountain site is suitable... determinations described in §§ 963.12 and 963.15. If DOE's evaluation of the Yucca Mountain site for the...
10 CFR 963.11 - Suitability determination.
Code of Federal Regulations, 2012 CFR
2012-01-01
... DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability Determination, Methods, and Criteria § 963.11 Suitability determination. DOE will evaluate whether the Yucca Mountain site is suitable... determinations described in §§ 963.12 and 963.15. If DOE's evaluation of the Yucca Mountain site for the...
10 CFR 963.11 - Suitability determination.
Code of Federal Regulations, 2011 CFR
2011-01-01
... DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability Determination, Methods, and Criteria § 963.11 Suitability determination. DOE will evaluate whether the Yucca Mountain site is suitable... determinations described in §§ 963.12 and 963.15. If DOE's evaluation of the Yucca Mountain site for the...
10 CFR 963.11 - Suitability determination.
Code of Federal Regulations, 2010 CFR
2010-01-01
... DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability Determination, Methods, and Criteria § 963.11 Suitability determination. DOE will evaluate whether the Yucca Mountain site is suitable... determinations described in §§ 963.12 and 963.15. If DOE's evaluation of the Yucca Mountain site for the...
Planning Non-Formal Education Curricula: The Case of Israel.
ERIC Educational Resources Information Center
Keller, Diana; Dror, Ilana
This paper compares the formal and non-formal education systems currently operating in Israel, describing the special features of curriculum planning in non-formal education. The central argument is that the non-formal education system fulfills functions that constitute a critique of the formal education system. The non-formal system offers the…
Are polymers suitable rock analogs?
NASA Astrophysics Data System (ADS)
ten Grotenhuis, Saskia M.; Piazolo, Sandra; Pakula, T.; Passchier, Cees W.; Bons, Paul D.
2002-05-01
To evaluate if a polymer is suitable for analog modeling, it is essential to know the rheological properties of the material. Polymers used in analog modeling exhibit a complex rheological behavior; only part of which has been taken into account in most modeling studies. The mechanical behavior is strongly dependent on strain rate and temperature, and is characterized by specific dependencies of the storage and loss moduli, related to the elasticity and viscosity, on the deformation rate (frequency). We have measured the storage and loss moduli at a broad range of strain rates and strains, using an oscillatory parallel-disk rheometer. Investigated materials are polydimethylsiloxane (PDMS), mixtures of PDMS and BaSO 4 (filler), Rhodorsil Gomme and mixtures of Rhodorsil Gomme and plastilina, all commonly used in analog experiments. Our measurements show that the rheological properties of mixtures of plastilina and Rhodorsil Gomme depend on its deformation history. Therefore, these mixtures are problematic for analog modeling. For mixtures of PDMS and BaSO 4, the significance of the elastic component increases with increasing filler content, and accordingly, these mixtures have a limited application for modeling of viscous deformation. Pure PDMS and Rhodorsil Gomme exhibit Newtonian flow behavior at strain rates commonly used in analog modeling.
Formalisms for user interface specification and design
NASA Technical Reports Server (NTRS)
Auernheimer, Brent J.
1989-01-01
The application of formal methods to the specification and design of human-computer interfaces is described. A broad outline of human-computer interface problems, a description of the field of cognitive engineering and two relevant research results, the appropriateness of formal specification techniques, and potential NASA application areas are described.
Integrating Formal and Informal Learning at Work
ERIC Educational Resources Information Center
Svensson, Lennart; Ellstrom, Per-Erik; Aberg, Carina
2004-01-01
A model for workplace learning is presented, which intends to integrate formal and informal learning with the use of e-learning. An important underlying assumption is that the integration of formal and informal learning is necessary in order to create desirable competencies, from both an individual and an organisational perspective. Two case…
The Formalization of Theory and Method.
ERIC Educational Resources Information Center
Freese, Lee
1981-01-01
Reviews the formalization of theory and method in American sociology since World War II, particularly the growth of systematic-formal theories and quantitative methods for empirical research. Topics discussed include various methods of theorizing, trends in theoretical sociology, and increasing use of quantitative data for data design and…
Male-Female Differences in Formal Thought.
ERIC Educational Resources Information Center
Linn, Marcia C.
Two studies were conducted to clarify the influence of experiences and aptitudes on male-female differences in formal thought. Participants were 788 seventh-, ninth-, and eleventh-graders in three school districts differing in location, socioeconomic composition, and course offerings. Formal thought was measured with tasks involving proportional…
Formal Mentoring Programs and Organizational Attraction
ERIC Educational Resources Information Center
Allen, Tammy D.; O'Brien, Kimberly E.
2006-01-01
This study was designed to test if formal mentoring programs enhance organizational attraction. Participants were 190 undergraduates looking for a job related to their major. Results indicated that participants were more attracted to an organization when it was depicted as having a formal mentoring program than when it was not so depicted. Drawing…
Do Formal Supports Replace Informal Supports?
ERIC Educational Resources Information Center
Barer, Barbara M.; And Others
Health policy researchers have long been interested in the extent to which the provision of formal supports replaces or undermines the informal support system. This study examined the linkages between the formal and informal support system as they are mediated by a health care setting which readily provides patients with access to social services.…
37 CFR 251.41 - Formal hearings.
Code of Federal Regulations, 2010 CFR
2010-07-01
... ARBITRATION ROYALTY PANEL RULES AND PROCEDURES COPYRIGHT ARBITRATION ROYALTY PANEL RULES OF PROCEDURE Procedures of Copyright Arbitration Royalty Panels § 251.41 Formal hearings. (a) The formal hearings that... distribution hearings. All parties intending to participate in a hearing of a Copyright Arbitration...
Does (In)Formal Learning Enhance Employability?
ERIC Educational Resources Information Center
van der Heijden, Beatrice I.J.M.; Boon, Jo; van der Klink, Marcel R.; Meys, Ely
2008-01-01
Not much is known about the actual contribution of informal learning to employability over and above formal learning activities. This paper presents findings of a research project among university staff members and is aimed to determine the contribution of formal and informal learning activities in the light of future career potential. Findings…
18 CFR 1b.5 - Formal investigations.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 18 Conservation of Power and Water Resources 1 2013-04-01 2013-04-01 false Formal investigations. 1b.5 Section 1b.5 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES RULES RELATING TO INVESTIGATIONS § 1b.5 Formal investigations....
18 CFR 1b.5 - Formal investigations.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Formal investigations. 1b.5 Section 1b.5 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES RULES RELATING TO INVESTIGATIONS § 1b.5 Formal investigations....
18 CFR 1b.5 - Formal investigations.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 18 Conservation of Power and Water Resources 1 2014-04-01 2014-04-01 false Formal investigations. 1b.5 Section 1b.5 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES RULES RELATING TO INVESTIGATIONS § 1b.5 Formal investigations....
18 CFR 1b.5 - Formal investigations.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 18 Conservation of Power and Water Resources 1 2012-04-01 2012-04-01 false Formal investigations. 1b.5 Section 1b.5 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES RULES RELATING TO INVESTIGATIONS § 1b.5 Formal investigations....
Multiverse in the Third Quantized Formalism
NASA Astrophysics Data System (ADS)
Mir, Faizal
2014-11-01
In this paper we will analyze the third quantization of gravity in path integral formalism. We will use the time-dependent version of Wheeler—DeWitt equation to analyze the multiverse in this formalism. We will propose a mechanism for baryogenesis to occur in the multiverse, without violating the baryon number conservation.
14 CFR 302.404 - Formal complaints.
Code of Federal Regulations, 2011 CFR
2011-01-01
... business or the ends of justice. (e) Service. A formal complaint, and any amendments thereto, shall be... does so under § 302.406(c). (b) Amendment. A formal complaint may be amended at any time before service of an answer to the complaint. After service of an answer but before institution of an...
14 CFR 302.404 - Formal complaints.
Code of Federal Regulations, 2012 CFR
2012-01-01
... business or the ends of justice. (e) Service. A formal complaint, and any amendments thereto, shall be... does so under § 302.406(c). (b) Amendment. A formal complaint may be amended at any time before service of an answer to the complaint. After service of an answer but before institution of an...
14 CFR 302.404 - Formal complaints.
Code of Federal Regulations, 2013 CFR
2013-01-01
... business or the ends of justice. (e) Service. A formal complaint, and any amendments thereto, shall be... does so under § 302.406(c). (b) Amendment. A formal complaint may be amended at any time before service of an answer to the complaint. After service of an answer but before institution of an...
14 CFR 302.404 - Formal complaints.
Code of Federal Regulations, 2014 CFR
2014-01-01
... business or the ends of justice. (e) Service. A formal complaint, and any amendments thereto, shall be... does so under § 302.406(c). (b) Amendment. A formal complaint may be amended at any time before service of an answer to the complaint. After service of an answer but before institution of an...
14 CFR 302.404 - Formal complaints.
Code of Federal Regulations, 2010 CFR
2010-01-01
... business or the ends of justice. (e) Service. A formal complaint, and any amendments thereto, shall be... does so under § 302.406(c). (b) Amendment. A formal complaint may be amended at any time before service of an answer to the complaint. After service of an answer but before institution of an...
18 CFR 1b.5 - Formal investigations.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Formal investigations. 1b.5 Section 1b.5 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES RULES RELATING TO INVESTIGATIONS § 1b.5 Formal investigations....
The Adolescent Personality, Formal Reasoning, and Values.
ERIC Educational Resources Information Center
Darmody, John P.
1991-01-01
Examined relationship between levels of Piagetian formal reasoning ability and values preferences derived from Rokeach Value Survey. Findings from 448 secondary school students revealed that subjects with high scores on formal reasoning ranked terminal values representing abstract notions with long-term implications higher than those focusing on…
Structuring the formal definition of Ada
NASA Technical Reports Server (NTRS)
Hansen, Kurt W.
1986-01-01
The structure of the formal definition of Ada are described. At present, a difficult subset of Ada has been defined and the experience gained so far by this work is reported. Currently, the work continues towards the formal definition of the Ada language.
Directly executable formal models of middleware for MANET and Cloud Networking and Computing
NASA Astrophysics Data System (ADS)
Pashchenko, D. V.; Sadeq Jaafar, Mustafa; Zinkin, S. A.; Trokoz, D. A.; Pashchenko, T. U.; Sinev, M. P.
2016-04-01
The article considers some “directly executable” formal models that are suitable for the specification of computing and networking in the cloud environment and other networks which are similar to wireless networks MANET. These models can be easily programmed and implemented on computer networks.
Unified formalism for nonautonomous mechanical systems
NASA Astrophysics Data System (ADS)
Barbero-Liñán, María; Echeverría-Enríquez, Arturo; Diego, David Martín de; Muñoz-Lecanda, Miguel C.; Román-Roy, Narciso
2008-06-01
We present a unified geometric framework for describing both the Lagrangian and Hamiltonian formalisms of regular and nonregular time-dependent mechanical systems, which is based on the approach of Skinner and Rusk ["Generalized Hamiltonian dynamics I. Formulation on T*Q⊗TQ," J. Math. Phys. 24, 2589 (1983)]. The dynamical equations of motion and their compatibility and consistency are carefully studied, making clear that all the characteristics of the Lagrangian and the Hamiltonian formalisms are recovered in this formulation. As an example, a semidiscretization of the nonlinear wave equation is studied, proving the applicability of the proposed formalism.
Generalized effective operator formalism for decaying systems
NASA Astrophysics Data System (ADS)
Paraschiv, Marius; Wölk, Sabine; Mannel, Thomas; Gühne, Otfried
2016-10-01
Systems of neutral kaons can be used to observe entanglement and the violation of Bell inequalities. The decay of these particles poses some problems, however, and recently an effective formalism for treating such systems has been derived. We generalize this formalism and make it applicable to other quantum systems that can be made to behave in a similar manner. As examples, we discuss two possible implementations of the generalized formalism using trapped ions such as 171Yb or 172Yb, which may be used to simulate kaonic behavior in a quantum optical system.
[Climatic suitability of citrus in subtropical China].
Duan, Hai-Lai; Qian, Huai-Sui; Li, Ming-Xia; Du, Yao-Dong
2010-08-01
By applying the theories of ecological suitability and the methods of fuzzy mathematics, this paper established a climatic suitability model for citrus, calculated and evaluated the climatic suitability and its spatiotemporal differences for citrus production in subtropical China, and analyzed the climatic suitability of citrus at its different growth stages and the mean climatic suitability of citrus in different regions of subtropical China. The results showed that the citrus in subtropical China had a lower climatic suitability and a higher risk at its flower bud differentiation stage, budding stage, and fruit maturity stage, but a higher climatic suitability and a lower risk at other growth stages. Cold damage and summer drought were the key issues affecting the citrus production in subtropical China. The citrus temperature suitability represented a latitudinal zonal pattern, i. e., decreased with increasing latitude; its precipitation suitability was high in the line of "Sheyang-Napo", medium in the southeast of the line, low in the northwest of the line, and non in high mountainous area; while the sunlight suitability was in line with the actual duration of sunshine, namely, higher in high-latitude areas than in low-latitude areas, and higher in high-altitude areas than in plain areas. Limited by temperature factor, the climatic suitability was in accordance with temperature suitability, i. e., south parts had a higher suitability than north parts, basically representing latitudinal zonal pattern. From the analysis of the inter-annual changes of citrus climatic suitability, it could be seen that the citrus climatic suitability in subtropical China was decreasing, and had obvious regional differences, suggesting that climate change could bring about the changes in the regions suitable for citrus production and in the key stages of citrus growth.
24 CFR 581.4 - Suitability determination.
Code of Federal Regulations, 2010 CFR
2010-04-01
... reviewed for suitability. HUD will maintain a written public record of the following: (1) The suitability... 24 Housing and Urban Development 3 2010-04-01 2010-04-01 false Suitability determination. 581.4... (Continued) OFFICE OF ASSISTANT SECRETARY FOR COMMUNITY PLANNING AND DEVELOPMENT, DEPARTMENT OF HOUSING...
A non-commuting stabilizer formalism
Ni, Xiaotong; Van den Nest, Maarten; Buerschaper, Oliver
2015-05-15
We propose a non-commutative extension of the Pauli stabilizer formalism. The aim is to describe a class of many-body quantum states which is richer than the standard Pauli stabilizer states. In our framework, stabilizer operators are tensor products of single-qubit operators drawn from the group 〈αI, X, S〉, where α = e{sup iπ/4} and S = diag(1, i). We provide techniques to efficiently compute various properties related to bipartite entanglement, expectation values of local observables, preparation by means of quantum circuits, parent Hamiltonians, etc. We also highlight significant differences compared to the Pauli stabilizer formalism. In particular, we give examples of states in our formalism which cannot arise in the Pauli stabilizer formalism, such as topological models that support non-Abelian anyons.
Why Engineers Should Consider Formal Methods
NASA Technical Reports Server (NTRS)
Holloway, C. Michael
1997-01-01
This paper presents a logical analysis of a typical argument favoring the use of formal methods for software development, and suggests an alternative argument that is simpler and stronger than the typical one.
Differences between Formal and Informal Communicative Channels.
ERIC Educational Resources Information Center
Johnson, J. David; And Others
1994-01-01
Compares formal and informal organizational communication structures within a large, technically oriented midwestern state governmental agency, specifically focusing on salience, channel factors, and channel usage. Suggests that informal channels in this organization were more highly evaluated in general. (SR)
Importance of Reversibility in the Quantum Formalism
NASA Astrophysics Data System (ADS)
David, François
2011-10-01
In this Letter I stress the role of causal reversibility (time symmetry), together with causality and locality, in the justification of the quantum formalism. First, in the algebraic quantum formalism, I show that the assumption of reversibility implies that the observables of a quantum theory form an abstract real C⋆ algebra, and can be represented as an algebra of operators on a real Hilbert space. Second, in the quantum logic formalism, I emphasize which axioms for the lattice of propositions (the existence of an orthocomplementation and the covering property) derive from reversibility. A new argument based on locality and Soler’s theorem is used to derive the representation as projectors on a regular Hilbert space from the general quantum logic formalism. In both cases it is recalled that the restriction to complex algebras and Hilbert spaces comes from the constraints of locality and separability.
Transitions from Formal Education to the Workplace
ERIC Educational Resources Information Center
Olson, Joann S.
2014-01-01
This chapter frames the transition to adulthood in the context of the moving from formal educational settings to the often less-structured learning that occurs in workplace settings. Although schooling may end, learning continues.
The adolescent personality, formal reasoning, and values.
Darmody, J P
1991-01-01
This study examined the relationship between levels of Piagetian formal reasoning ability and values preferences derived from the Rokeach Value Survey. The subjects were 448 secondary school students (mean age = 16.25 years). The results of the study were consistent with predictions about the likely changes in value rankings as formal reasoning ability develops. Subjects with high scores on formal reasoning ranked terminal values representing abstract notions with long-term implications higher than those focusing on immediate gratification. They also favored the instrumental values of self-reliance, competence, and independence. Low scorers on formal reasoning showed a preference for value groupings which were personal, hedonistic, and involved immediate gratification and social approval. PMID:1962555
Formal Instruction in Dental Professional Ethics.
ERIC Educational Resources Information Center
Ozar, David T.
1985-01-01
Three common arguments against formal classes in professional ethics are examined. A minimum curriculum in dental professional ethics is proposed and a proposed program in professional ethics in dentistry is appended. (MLW)
Open systems & non-formal education
NASA Astrophysics Data System (ADS)
Wheeler, Gerald F.
1988-10-01
Professor Dib created an important structure that can be used to attach the many and various activities that fall in the category of this title. While I plan to use his structure, I will be emphasizing a different component of his spectrum and promoting a different need. Professor Dib suggested a critical need to move our teaching styles away from formal modes to non-formal modes of delivery. I suggest an equally critical need in the area of informal education. And, I will propose aways to move us toward the same goal, non-formal activities. I believe we need to find ways to use the many informal education activities that occur almost automatically in our societies to move our potential learners to richer non-formal endeavors. Both needs are real; both activities are valid.
Experiences Using Formal Methods for Requirements Modeling
NASA Technical Reports Server (NTRS)
Easterbrook, Steve; Lutz, Robyn; Covington, Rick; Kelly, John; Ampo, Yoko; Hamilton, David
1996-01-01
This paper describes three cases studies in the lightweight application of formal methods to requirements modeling for spacecraft fault protection systems. The case studies differ from previously reported applications of formal methods in that formal methods were applied very early in the requirements engineering process, to validate the evolving requirements. The results were fed back into the projects, to improve the informal specifications. For each case study, we describe what methods were applied, how they were applied, how much effort was involved, and what the findings were. In all three cases, the formal modeling provided a cost effective enhancement of the existing verification and validation processes. We conclude that the benefits gained from early modeling of unstable requirements more than outweigh the effort needed to maintain multiple representations.
General formalism for singly thermostated Hamiltonian dynamics
NASA Astrophysics Data System (ADS)
Ramshaw, John D.
2015-11-01
A general formalism is developed for constructing modified Hamiltonian dynamical systems which preserve a canonical equilibrium distribution by adding a time evolution equation for a single additional thermostat variable. When such systems are ergodic, canonical ensemble averages can be computed as dynamical time averages over a single trajectory. Systems of this type were unknown until their recent discovery by Hoover and colleagues. The present formalism should facilitate the discovery, construction, and classification of other such systems by encompassing a wide class of them within a single unified framework. This formalism includes both canonical and generalized Hamiltonian systems in a state space of arbitrary dimensionality (either even or odd) and therefore encompasses both few- and many-particle systems. Particular attention is devoted to the physical motivation and interpretation of the formalism, which largely determine its structure. An analogy to stochastic thermostats and fluctuation-dissipation theorems is briefly discussed.
Formal specification of human-computer interfaces
NASA Technical Reports Server (NTRS)
Auernheimer, Brent
1990-01-01
A high-level formal specification of a human computer interface is described. Previous work is reviewed and the ASLAN specification language is described. Top-level specifications written in ASLAN for a library and a multiwindow interface are discussed.
Elements of (Super-)Hamiltonian Formalism
NASA Astrophysics Data System (ADS)
Nersessian, A.
In these lectures we discuss some basic aspects of Hamiltonian formalism, which usually do not appear in standard textbooks on classical mechanics for physicists. We pay special attention to the procedure of Hamiltonian reduction illustrating it by the examples related to Hopf maps. Then we briefly discuss the supergeneralization(s) of the Hamiltonian formalism and present some simple models of supersymmetric mechanics on Kähler manifolds.
Formal verification of an avionics microprocessor
NASA Technical Reports Server (NTRS)
Srivas, Mandayam, K.; Miller, Steven P.
1995-01-01
Formal specification combined with mechanical verification is a promising approach for achieving the extremely high levels of assurance required of safety-critical digital systems. However, many questions remain regarding their use in practice: Can these techniques scale up to industrial systems, where are they likely to be useful, and how should industry go about incorporating them into practice? This report discusses a project undertaken to answer some of these questions, the formal verification of the AAMPS microprocessor. This project consisted of formally specifying in the PVS language a rockwell proprietary microprocessor at both the instruction-set and register-transfer levels and using the PVS theorem prover to show that the microcode correctly implemented the instruction-level specification for a representative subset of instructions. Notable aspects of this project include the use of a formal specification language by practicing hardware and software engineers, the integration of traditional inspections with formal specifications, and the use of a mechanical theorem prover to verify a portion of a commercial, pipelined microprocessor that was not explicitly designed for formal verification.
Formality of the Chinese collective leadership.
Li, Haiying; Graesser, Arthur C
2016-09-01
We investigated the linguistic patterns in the discourse of four generations of the collective leadership of the Communist Party of China (CPC) from 1921 to 2012. The texts of Mao Zedong, Deng Xiaoping, Jiang Zemin, and Hu Jintao were analyzed using computational linguistic techniques (a Chinese formality score) to explore the persuasive linguistic features of the leaders in the contexts of power phase, the nation's education level, power duration, and age. The study was guided by the elaboration likelihood model of persuasion, which includes a central route (represented by formal discourse) versus a peripheral route (represented by informal discourse) to persuasion. The results revealed that these leaders adopted the formal, central route more when they were in power than before they came into power. The nation's education level was a significant factor in the leaders' adoption of the persuasion strategy. The leaders' formality also decreased with their increasing age and in-power times. However, the predictability of these factors for formality had subtle differences among the different types of leaders. These results enhance our understanding of the Chinese collective leadership and the role of formality in politically persuasive messages. PMID:27406253
Formality of the Chinese collective leadership.
Li, Haiying; Graesser, Arthur C
2016-09-01
We investigated the linguistic patterns in the discourse of four generations of the collective leadership of the Communist Party of China (CPC) from 1921 to 2012. The texts of Mao Zedong, Deng Xiaoping, Jiang Zemin, and Hu Jintao were analyzed using computational linguistic techniques (a Chinese formality score) to explore the persuasive linguistic features of the leaders in the contexts of power phase, the nation's education level, power duration, and age. The study was guided by the elaboration likelihood model of persuasion, which includes a central route (represented by formal discourse) versus a peripheral route (represented by informal discourse) to persuasion. The results revealed that these leaders adopted the formal, central route more when they were in power than before they came into power. The nation's education level was a significant factor in the leaders' adoption of the persuasion strategy. The leaders' formality also decreased with their increasing age and in-power times. However, the predictability of these factors for formality had subtle differences among the different types of leaders. These results enhance our understanding of the Chinese collective leadership and the role of formality in politically persuasive messages.
Formal Methods for Verification and Validation of Partial Specifications: A Case Study
NASA Technical Reports Server (NTRS)
Easterbrook, Steve; Callahan, John
1997-01-01
This paper describes our work exploring the suitability of formal specification methods for independent verification and validation (IV&V) of software specifications for large, safety critical systems. An IV&V contractor often has to perform rapid analysis on incomplete specifications, with no control over how those specifications are represented. Lightweight formal methods show significant promise in this context, as they offer a way of uncovering major errors, without the burden of full proofs of correctness. We describe a case study of the use of partial formal models for V&V of the requirements for Fault Detection Isolation and Recovery on the space station. We conclude that the insights gained from formalizing a specification are valuable, and it is the process of formalization, rather than the end product that is important. It was only necessary to build enough of the formal model to test the properties in which we were interested. Maintenance of fidelity between multiple representations of the same requirements (as they evolve) is still a problem, and deserves further study.
Conditions for periodic and aperiodic behavior of formal neural nets.
Labos, E
1994-05-01
Formal neural networks (FNN) can display dynamical behaviours, more or less different from each other depending on their units, the functions attributed to these units, interconnections, parameters, state spaces and initial states, etc. Whatever is 'chaos' - of which several practical and more exact definitions exist -, it used to be emerging at special conditions. Its prediction most often requires an individual analysis of the dynamical system (DS) in question. A study of such conditions is usually necessary in order to reach suitable control, which now seems to become a new trend in chaos theory. In chaos control tasks quick commands and at least short-term foresight of trends are required. It is a primary question also to define in advance what is regarded to be a controlled case of chaos. Possible importance of these general considerations at molecular scale is also discussed, avoiding not well-founded speculations.
Formalism for Hypercomplex Multidimensional NMR Employing Partial-Component Subsampling
Schuyler, Adam D; Maciejewski, Mark W; Stern, Alan S; Hoch, Jeffrey C
2012-01-01
Multidimensional NMR spectroscopy typically employs phase-sensitive detection, which results in hypercomplex data (and spectra) when utilized in more than one dimension. Nonuniform sampling approaches have become commonplace in multidimensional NMR, enabling dramatic reductions in experiment time, increases in sensitivity and/or increases in resolution. In order to utilize nonuniform sampling optimally, it is necessary to characterize the relationship between the spectrum of a uniformly sampled data set and the spectrum of a subsampled data set. In this work we construct an algebra of hypercomplex numbers suitable for representing multidimensional NMR data along with partial-component nonuniform sampling (i.e. the hypercomplex components of data points are subsampled). This formalism leads to a modified DFT–convolution relationship involving a partial-component, hypercomplex point-spread function set. The framework presented here is essential for the continued development and appropriate characterization of partial-component nonuniform sampling. PMID:23246651
Formal methods for Hopfield-like networks.
Ben Amor, Hedi; Corblin, Fabien; Fanchon, Eric; Elena, Adrien; Trilling, Laurent; Demongeot, Jacques; Glade, Nicolas
2013-03-01
Building a meaningful model of biological regulatory network is usually done by specifying the components (e.g. the genes) and their interactions, by guessing the values of parameters, by comparing the predicted behaviors to the observed ones, and by modifying in a trial-error process both architecture and parameters in order to reach an optimal fitness. We propose here a different approach to construct and analyze biological models avoiding the trial-error part, where structure and dynamics are represented as formal constraints. We apply the method to Hopfield-like networks, a formalism often used in both neural and regulatory networks modeling. The aim is to characterize automatically the set of all models consistent with all the available knowledge (about structure and behavior). The available knowledge is formalized into formal constraints. The latter are compiled into Boolean formula in conjunctive normal form and then submitted to a Boolean satisfiability solver. This approach allows to formulate a wide range of queries, expressed in a high level language, and possibly integrating formalized intuitions. In order to explore its potential, we use it to find cycles for 3-nodes networks and to determine the flower morphogenesis regulatory network of Arabidopsis thaliana. Applications of this technique are numerous and concern the building of models from data as well as the design of biological networks possessing specified behaviors. PMID:23381497
Formal Methods Case Studies for DO-333
NASA Technical Reports Server (NTRS)
Cofer, Darren; Miller, Steven P.
2014-01-01
RTCA DO-333, Formal Methods Supplement to DO-178C and DO-278A provides guidance for software developers wishing to use formal methods in the certification of airborne systems and air traffic management systems. The supplement identifies the modifications and additions to DO-178C and DO-278A objectives, activities, and software life cycle data that should be addressed when formal methods are used as part of the software development process. This report presents three case studies describing the use of different classes of formal methods to satisfy certification objectives for a common avionics example - a dual-channel Flight Guidance System. The three case studies illustrate the use of theorem proving, model checking, and abstract interpretation. The material presented is not intended to represent a complete certification effort. Rather, the purpose is to illustrate how formal methods can be used in a realistic avionics software development project, with a focus on the evidence produced that could be used to satisfy the verification objectives found in Section 6 of DO-178C.
Habitat Suitability Index Models: Pileated woodpecker
Schroeder, Richard L.
1983-01-01
A review and synthesis of existing information was used to develop a habitat model for the pileated woodpecker (Dryocopus pileatus). The model is scaled to produce an index of habitat suitability between 0 (unsuitable habitat) and 1 (optimally suitable habitat) for areas of the continental United States. Habitat suitability indexes are designed for use.with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
A Formal Model of Partitioning for Integrated Modular Avionics
NASA Technical Reports Server (NTRS)
DiVito, Ben L.
1998-01-01
The aviation industry is gradually moving toward the use of integrated modular avionics (IMA) for civilian transport aircraft. An important concern for IMA is ensuring that applications are safely partitioned so they cannot interfere with one another. We have investigated the problem of ensuring safe partitioning and logical non-interference among separate applications running on a shared Avionics Computer Resource (ACR). This research was performed in the context of ongoing standardization efforts, in particular, the work of RTCA committee SC-182, and the recently completed ARINC 653 application executive (APEX) interface standard. We have developed a formal model of partitioning suitable for evaluating the design of an ACR. The model draws from the mathematical modeling techniques developed by the computer security community. This report presents a formulation of partitioning requirements expressed first using conventional mathematical notation, then formalized using the language of SRI'S Prototype Verification System (PVS). The approach is demonstrated on three candidate designs, each an abstraction of features found in real systems.
Habitat Suitability Index Models: Bigmouth buffalo
Edwards, Elizabeth A.
1983-01-01
A review and synthesis of existing information were used to develop riverine and lacustrine habitat models for Bigmouth buffalo (Ictiobus cyprinellus), a freshwater fish. The models are scaled to produce an indices of habitat suitability between 0 (unsuitable habitat) and 1 (optimally suitable habitat) for freshwater areas of the continental United States. Other habitat suitability models found in the literature are also included. Habitat suitability indices (HSI's) are designed for use with the habitat evaluation procedures developed by the U.S. Fish and Wildlife Service.
The Nation's Needs in Aviation Formal Methods
NASA Technical Reports Server (NTRS)
Pritchett, Amy R.
2008-01-01
Aviation, both on-board systems and the National Airspace System, can be transformed by many current and future technical capabilities. To name but a few, improved efficiency may be achieved by integrating functions; robustness may be improved by distributing functions; and safety may be improved by building in risk mitigation through not only redundant, independent systems but also through operational concepts and effective interaction with human operators. This talk will review the key aspects of verification, validation and certification for which formal methods will provide a critical function in enabling truly revolutionary designs to enter the operational community, illustrating successes in formal modeling to date and posing further questions for the formal modeling community.
Formalizing Darwinism and inclusive fitness theory.
Grafen, Alan
2009-11-12
Inclusive fitness maximization is a basic building block for biological contributions to any theory of the evolution of society. There is a view in mathematical population genetics that nothing is caused to be maximized in the process of natural selection, but this is explained as arising from a misunderstanding about the meaning of fitness maximization. Current theoretical work on inclusive fitness is discussed, with emphasis on the author's 'formal Darwinism project'. Generally, favourable conclusions are drawn about the validity of assuming fitness maximization, but the need for continuing work is emphasized, along with the possibility that substantive exceptions may be uncovered. The formal Darwinism project aims more ambitiously to represent in a formal mathematical framework the central point of Darwin's Origin of Species, that the mechanical processes of inheritance and reproduction can give rise to the appearance of design, and it is a fitting ambition in Darwin's bicentenary year to capture his most profound discovery in the lingua franca of science.
User Interface Technology for Formal Specification Development
NASA Technical Reports Server (NTRS)
Lowry, Michael; Philpot, Andrew; Pressburger, Thomas; Underwood, Ian; Lum, Henry, Jr. (Technical Monitor)
1994-01-01
Formal specification development and modification are an essential component of the knowledge-based software life cycle. User interface technology is needed to empower end-users to create their own formal specifications. This paper describes the advanced user interface for AMPHION1 a knowledge-based software engineering system that targets scientific subroutine libraries. AMPHION is a generic, domain-independent architecture that is specialized to an application domain through a declarative domain theory. Formal specification development and reuse is made accessible to end-users through an intuitive graphical interface that provides semantic guidance in creating diagrams denoting formal specifications in an application domain. The diagrams also serve to document the specifications. Automatic deductive program synthesis ensures that end-user specifications are correctly implemented. The tables that drive AMPHION's user interface are automatically compiled from a domain theory; portions of the interface can be customized by the end-user. The user interface facilitates formal specification development by hiding syntactic details, such as logical notation. It also turns some of the barriers for end-user specification development associated with strongly typed formal languages into active sources of guidance, without restricting advanced users. The interface is especially suited for specification modification. AMPHION has been applied to the domain of solar system kinematics through the development of a declarative domain theory. Testing over six months with planetary scientists indicates that AMPHION's interactive specification acquisition paradigm enables users to develop, modify, and reuse specifications at least an order of magnitude more rapidly than manual program development.
Combining Formal, Non-Formal and Informal Learning for Workforce Skill Development
ERIC Educational Resources Information Center
Misko, Josie
2008-01-01
This literature review, undertaken for Australian Industry Group, shows how multiple variations and combinations of formal, informal and non-formal learning, accompanied by various government incentives and organisational initiatives (including job redesign, cross-skilling, multi-skilling, diversified career pathways, action learning projects,…
ERIC Educational Resources Information Center
Cameron, Roslyn; Harrison, Jennifer L.
2012-01-01
Definitions, differences and relationships between formal, non-formal and informal learning have long been contentious. There has been a significant change in language and reference from adult education to what amounts to forms of learning categorised by their modes of facilitation. Nonetheless, there is currently a renewed interest in the…
ERIC Educational Resources Information Center
de Lange, Thomas
2011-01-01
This article examines how a classroom procedure known as PGE (Plan/Go-through/Evaluate) group work aims at integrating formal and non-formal media experiences and practices into classroom-based media learning. The study displays, on the one hand, how PGE group work emerged and was institutionally embedded in a media course. On the other hand, the…
The Comparative Functionality of Formal and Non-Formal Education for Women: Final Report.
ERIC Educational Resources Information Center
Derryck, Vivian Lowery
This final report describes a five-phase study to ascertain whether formal or non-formal education has the greater functionality to accelerate women's integration into development activities. Part 1 (two chapters), introduction and background, defines the problem, sets parameters of the study, and provides definitions of education terms. Part 2…
Extending the ADM formalism to Weyl geometry
NASA Astrophysics Data System (ADS)
Barreto, A. B.; Almeida, T. S.; Romero, C.
2015-03-01
In order to treat quantum cosmology in the framework of Weyl spacetimes we take the first step of extending the Arnowitt-Deser-Misner formalism to Weyl geometry. We then obtain an expression of the curvature tensor in terms of spatial quantities by splitting spacetime in (3+l)-dimensional form. We next write the Lagrangian of the gravitation field based in Weyl-type gravity theory. We extend the general relativistic formalism in such a way that it can be applied to investigate the quantum cosmology of models whose spacetimes are endowed with a Weyl geometrical structure.
NASA Astrophysics Data System (ADS)
Tignanelli, H.
Se comentan en esta comunicación, las principales contribuciones realizadas en el campo de la educación en astronomía en los niveles primario, secundario y terciario, como punto de partida para la discusión de la actual inserción de los contenidos astronómicos en los nuevos contenidos curriculares de la EGB - Educación General Básica- y Polimodal, de la Reforma Educativa. En particular, se discuten los alcances de la educación formal y no formal, su importancia para la capacitación de profesores y maestros, y perspectivas a futuro.
Extending the ADM formalism to Weyl geometry
Barreto, A. B.; Almeida, T. S.; Romero, C.
2015-03-26
In order to treat quantum cosmology in the framework of Weyl spacetimes we take the first step of extending the Arnowitt-Deser-Misner formalism to Weyl geometry. We then obtain an expression of the curvature tensor in terms of spatial quantities by splitting spacetime in (3+l)-dimensional form. We next write the Lagrangian of the gravitation field based in Weyl-type gravity theory. We extend the general relativistic formalism in such a way that it can be applied to investigate the quantum cosmology of models whose spacetimes are endowed with a Weyl geometrical structure.
Generative Graph Grammar of Neo-Vaiśeṣika Formal Ontology (NVFO)
NASA Astrophysics Data System (ADS)
Tavva, Rajesh; Singh, Navjyoti
NLP applications for Sanskrit so far work within computational paradigm of string grammars. However, to compute 'meanings', as in traditional śā bdabodha prakriyā-s, there is a need to develop suitable graph grammars. Ontological structures are fundamentally graphs. We work within the formal framework of Neo-Vaiśeṣika Formal Ontology (NVFO) to propose a generative graph grammar. The proposed formal grammar only produces well-formed graphs that can be readily interpreted in accordance with Vaiśeṣ ika Ontology. We show that graphs not permitted by Vaiśeṣ ika ontology are not generated by the proposed grammar. Further, we write Interpreter of these graphical structures. This creates computational environment which can be deployed for writing computational applications of Vaiśeṣ ika ontology. We illustrate how this environment can be used to create applications like computing śā bdabodha of sentences.
Formal Synthesis of (±)-Roseophilin
Bitar, Abdallah Y.; Frontier, Alison J.
2009-01-01
A formal synthesis of (±)-roseophilin is described. Scandium(III)-catalyzed Nazarov cyclization of 2,5-disubstituted N-tosylpyrrole 19 gives a 5,5’-fused ketopyrrole, and ansa-bridge formation via π-allyl palladium macrocyclization gives 21. PMID:19053717
The Transition to Formal Thinking in Mathematics
ERIC Educational Resources Information Center
Tall, David
2008-01-01
This paper focuses on the changes in thinking involved in the transition from school mathematics to formal proof in pure mathematics at university. School mathematics is seen as a combination of visual representations, including geometry and graphs, together with symbolic calculations and manipulations. Pure mathematics in university shifts…
Weak rigidity in the PPN formalism
del Olmo, V.; Olivert, J.
1987-04-01
The influence of the concept of weakly rigid almost-thermodynamic material schemes on the classical deformations is analyzed. The methods of the PPN approximation are considered. In this formalism, the equations that characterize the weak rigidity are expressed. As a consequence of that, an increase of two orders of magnitude in the strain rate tensor is obtained.
Formalization and Analysis of Reasoning by Assumption
ERIC Educational Resources Information Center
Bosse, Tibor; Jonker, Catholijn M.; Treur, Jan
2006-01-01
This article introduces a novel approach for the analysis of the dynamics of reasoning processes and explores its applicability for the reasoning pattern called reasoning by assumption. More specifically, for a case study in the domain of a Master Mind game, it is shown how empirical human reasoning traces can be formalized and automatically…
Helping Students Understand Formal Chemical Concepts.
ERIC Educational Resources Information Center
Ward, Charles R.; Herron, J. Dudley
1980-01-01
Investigated outcomes of the use of the learning cycle, which divides instruction into the Piagetian phases of exploration, invention, and discovery in general college chemistry laboratory experiments. Differences between concrete and formal operational students were explored in students' ability to master chemistry material varying in cognitive…
Formal and Applied Counseling in Israel
ERIC Educational Resources Information Center
Israelashvili, Moshe; Wegman-Rozi, Orit
2012-01-01
Living in Israel is intensive and demanding but also meaningful and exciting. This article addresses the gap between the narrowly defined formal status of counseling in Israel and the widespread occurrence of counseling in various settings. It is argued that several recent changes, especially in the definition of treatment, along with the…
A Simplified Approach to Product Operator Formalism
ERIC Educational Resources Information Center
Spiese, Christopher E.
2004-01-01
The utilization of the simple and traditional vector model-based product operator formalism is highlighted. It is seen as a critical device in the area of nuclear magnetic resonance (NMR) spectrometry for a comprehensive analysis of spin coupling and quantum coherences.
Quantum formalism to describe binocular rivalry.
Manousakis, Efstratios
2009-11-01
On the basis of the general character and operation of the process of perception, a formalism is sought to mathematically describe the subjective or abstract/mental process of perception. It is shown that the formalism of orthodox quantum theory of measurement, where the observer plays a key role, is a broader mathematical foundation which can be adopted to describe the dynamics of the subjective experience. The mathematical formalism describes the psychophysical dynamics of the subjective or cognitive experience as communicated to us by the subject. Subsequently, the formalism is used to describe simple perception processes and, in particular, to describe the probability distribution of dominance duration obtained from the testimony of subjects experiencing binocular rivalry. Using this theory and parameters based on known values of neuronal oscillation frequencies and firing rates, the calculated probability distribution of dominance duration of rival states in binocular rivalry under various conditions is found to be in good agreement with available experimental data. This theory naturally explains an observed marked increase in dominance duration in binocular rivalry upon periodic interruption of stimulus and yields testable predictions for the distribution of perceptual alteration in time. PMID:19520143
Conservation-dissipation formalism of irreversible thermodynamics
NASA Astrophysics Data System (ADS)
Zhu, Yi; Hong, Liu; Yang, Zaibao; Yong, Wen-An
2015-06-01
We propose a conservation-dissipation formalism (CDF) for coarse-grained descriptions of irreversible processes. This formalism is based on a stability criterion for non-equilibrium thermodynamics. The criterion ensures that non-equilibrium states tend to equilibrium in long time. As a systematic methodology, CDF provides a feasible procedure in choosing non-equilibrium state variables and determining their evolution equations. The equations derived in CDF have a unified elegant form. They are globally hyperbolic, allow a convenient definition of weak solutions, and are amenable to existing numerics. More importantly, CDF is a genuinely nonlinear formalism and works for systems far away from equilibrium. With this formalism, we formulate novel thermodynamics theories for heat conduction in rigid bodies and non-isothermal compressible Maxwell fluid flows as two typical examples. In these examples, the non-equilibrium variables are exactly the conjugate variables of the heat fluxes or stress tensors. The new theory generalizes Cattaneo's law or Maxwell's law in a regularized and nonlinear fashion.
39 CFR 3001.20 - Formal intervention.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 39 Postal Service 1 2012-07-01 2012-07-01 false Formal intervention. 3001.20 Section 3001.20... position of the intervenor with regard to the proposed changes in postal rates, fees, classifications, or... responses to discovery requests filed by that intervenor. (e) Effect of intervention. A person filing...
39 CFR 3001.20 - Formal intervention.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 39 Postal Service 1 2014-07-01 2014-07-01 false Formal intervention. 3001.20 Section 3001.20... proposed changes in postal rates, fees, classifications, or services, or the subject matter of the... intervention shall delay on a day-for-day basis, the date for responses to discovery requests filed by...
39 CFR 3001.20 - Formal intervention.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 39 Postal Service 1 2011-07-01 2011-07-01 false Formal intervention. 3001.20 Section 3001.20... position of the intervenor with regard to the proposed changes in postal rates, fees, classifications, or... responses to discovery requests filed by that intervenor. (e) Effect of intervention. A person filing...
39 CFR 3001.20 - Formal intervention.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 39 Postal Service 1 2013-07-01 2013-07-01 false Formal intervention. 3001.20 Section 3001.20... position of the intervenor with regard to the proposed changes in postal rates, fees, classifications, or... responses to discovery requests filed by that intervenor. (e) Effect of intervention. A person filing...
Connecting Formal and Informal Learning Experiences
ERIC Educational Resources Information Center
O'Mahony, Timothy Kieran
2010-01-01
The learning study reports on part of a larger project being lead by the author. In this dissertation I explore one goal of this project--to understand effects on student learning outcomes as a function of using different methods for connecting out-of-school experiential learning with formal school-based instruction. There is a long history of…
Male caregivers' use of formal support.
Coe, M; Neufeld, A
1999-08-01
The purpose of this study was to explore male caregivers' perceptions of formal support. The men were caregivers of adults with cognitive impairment. The study involved secondary analysis of interview data on perceptions of support that had not been previously analyzed from the perspective of formal support. Techniques of data analysis used in grounded theory were applied to 62 guided interactive interviews conducted with 24 male caregivers during a period of 18 months. The men experienced a process of making concessions for care in the following four sequential stages: resisting, giving in, opening the door, and making the match. Personal barriers deterred the caregivers from seeking help, and once the caregivers engaged formal help the influence of characteristics of the health care system and individual staff members had both enabling and disabling effects. For caregivers whose use of formal support involved admitting their relative to a long-term care facility, the phase of making the match was followed by redesigning their caregiver role. PMID:11512171
Formal Schema Theory and Teaching EFL Reading
ERIC Educational Resources Information Center
Young, Barbara N; Man, Zhou
2005-01-01
Inquirers designed and conducted a study investigating whether or not results derived from previous research focusing on teaching and learning English as a native or foreign language would be replicated in a learning environment in which English is taught as a foreign language as in China. Because activation of formal schemata plays an important…
Formal Thought at the High School Level
ERIC Educational Resources Information Center
Johnson, Donald
1977-01-01
A study was undertaken to determine the Piagetian stages of intellectual development of a group of Saskatchewan high school students. Results confirmed that the percentage of students at the final substage of formal thought was less than 50 percent, indicating serious problems. (JC)
50 CFR 402.14 - Formal consultation.
Code of Federal Regulations, 2010 CFR
2010-10-01
... OF COMMERCE); ENDANGERED SPECIES COMMITTEE REGULATIONS SUBCHAPTER A INTERAGENCY COOPERATION-ENDANGERED SPECIES ACT OF 1973, AS AMENDED Consultation Procedures § 402.14 Formal consultation. (a... time to determine whether any action may affect listed species or critical habitat. If such...
50 CFR 402.14 - Formal consultation.
Code of Federal Regulations, 2014 CFR
2014-10-01
..., DEPARTMENT OF COMMERCE); ENDANGERED SPECIES COMMITTEE REGULATIONS SUBCHAPTER A INTERAGENCY COOPERATION-ENDANGERED SPECIES ACT OF 1973, AS AMENDED Consultation Procedures § 402.14 Formal consultation. (a... time to determine whether any action may affect listed species or critical habitat. If such...
50 CFR 402.14 - Formal consultation.
Code of Federal Regulations, 2012 CFR
2012-10-01
..., DEPARTMENT OF COMMERCE); ENDANGERED SPECIES COMMITTEE REGULATIONS SUBCHAPTER A INTERAGENCY COOPERATION-ENDANGERED SPECIES ACT OF 1973, AS AMENDED Consultation Procedures § 402.14 Formal consultation. (a... time to determine whether any action may affect listed species or critical habitat. If such...
50 CFR 402.14 - Formal consultation.
Code of Federal Regulations, 2013 CFR
2013-10-01
..., DEPARTMENT OF COMMERCE); ENDANGERED SPECIES COMMITTEE REGULATIONS SUBCHAPTER A INTERAGENCY COOPERATION-ENDANGERED SPECIES ACT OF 1973, AS AMENDED Consultation Procedures § 402.14 Formal consultation. (a... time to determine whether any action may affect listed species or critical habitat. If such...
50 CFR 402.14 - Formal consultation.
Code of Federal Regulations, 2011 CFR
2011-10-01
... OF COMMERCE); ENDANGERED SPECIES COMMITTEE REGULATIONS SUBCHAPTER A INTERAGENCY COOPERATION-ENDANGERED SPECIES ACT OF 1973, AS AMENDED Consultation Procedures § 402.14 Formal consultation. (a... time to determine whether any action may affect listed species or critical habitat. If such...
28 CFR 68.39 - Formal hearings.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Formal hearings. 68.39 Section 68.39 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) RULES OF PRACTICE AND PROCEDURE FOR ADMINISTRATIVE HEARINGS BEFORE ADMINISTRATIVE LAW JUDGES IN CASES INVOLVING ALLEGATIONS OF UNLAWFUL EMPLOYMENT...
Convergent formal synthesis of (±)-roseophilin.
Song, Chuanjun; Liu, Hui; Hong, Meiling; Liu, Yuanyuan; Jia, Feifei; Sun, Li; Pan, Zhenliang; Chang, Junbiao
2012-01-01
A facile convergent synthesis of the tricyclic core 2 of roseophilin is described, which represents the shortest route so far for the formal synthesis of roseophilin. The key step was a tandem pyrrole acylation-Nazarov cyclization reaction to form the cyclopenta[b]pyrrole moiety 4. PMID:22098172
Informal Science Learning in the Formal Classroom
ERIC Educational Resources Information Center
Walsh, Lori; Straits, William
2014-01-01
In this article the authors share advice from the viewpoints of both a formal and informal educator that will help teachers identify the right Informal Science Institutions (ISIs)--institutions that specialize in learning that occurs outside of the school setting--to maximize their students' learning and use informal education to their…
Teaching Some Informatics Concepts Using Formal System
ERIC Educational Resources Information Center
Yang, Sojung; Park, Seongbin
2014-01-01
There are many important issues in informatics and many agree that algorithms and programming are most important issues that need to be included in informatics education (Dagiene and Jevsikova, 2012). In this paper, we propose how some of these issues can be easily taught using the notion of a formal system which consists of axioms and inference…
Formal Foundations for Hierarchical Safety Cases
NASA Technical Reports Server (NTRS)
Denney, Ewen; Pai, Ganesh; Whiteside, Iain
2015-01-01
Safety cases are increasingly being required in many safety-critical domains to assure, using structured argumentation and evidence, that a system is acceptably safe. However, comprehensive system-wide safety arguments present appreciable challenges to develop, understand, evaluate, and manage, partly due to the volume of information that they aggregate, such as the results of hazard analysis, requirements analysis, testing, formal verification, and other engineering activities. Previously, we have proposed hierarchical safety cases, hicases, to aid the comprehension of safety case argument structures. In this paper, we build on a formal notion of safety case to formalise the use of hierarchy as a structuring technique, and show that hicases satisfy several desirable properties. Our aim is to provide a formal, theoretical foundation for safety cases. In particular, we believe that tools for high assurance systems should be granted similar assurance to the systems to which they are applied. To this end, we formally specify and prove the correctness of key operations for constructing and managing hicases, which gives the specification for implementing hicases in AdvoCATE, our toolset for safety case automation. We motivate and explain the theory with the help of a simple running example, extracted from a real safety case and developed using AdvoCATE.
Identifying Concrete and Formal Operational Children.
ERIC Educational Resources Information Center
Docherty, Edward M.
This paper presents a study designed to determine if groups of concrete and formal operational children can be identified through the technique of cluster analysis, using a battery of Piagetian tasks. A Total of 64 subjects, 8 boys and 8 girls from each of the second, fourth, sixth, and eighth grade levels, were selected from a public elementary…
An Elementary Formalism for General Relativity.
ERIC Educational Resources Information Center
diSessa, Andrea A.
1981-01-01
An elementary formalism is developed for representing curved space-time which allows transparent qualitative explanation of general relativistic effects and is used to make a conceptual analysis of Einstein's principle of equivalence. A final section outlines a number of student activities. (Author/SK)
Safety in Children's Formal Play Environments.
ERIC Educational Resources Information Center
Wilkinson, Paul F.; Lockhart, Robert
This study was designed to examine the issue of the safety of children's formal play environments. Safety was defined in terms of morbidity and mortality data. Protection and safety education were considered the prime factors in accident prevention while the goal of a safety program was considered to be the minimizing of injuries. Several data…
HIV Education in the Formal Curriculum
ERIC Educational Resources Information Center
Nsubuga, Yusuf K.; Bonnet, Sandrine
2009-01-01
The AIDS epidemic presents a complex of issues that require global answers, involving entire societies. The only sustainable solution is to include all sectors of society in a multidisciplinary collaboration, within which the formal education system plays a key role in delivering a comprehensive response to the disease at the national level.…
Formalism and the notion of truth
NASA Astrophysics Data System (ADS)
Spencer, Joseph M.
The most widely acknowledged conceptions of truth take some kind of relation to be at truth's core. This dissertation attempts to establish that an adequate conception of this relation begins with an investigation of the entanglement of the formal and the material as set forth in the model theoretical development of set theoretical mathematics. Truth concerns first and most crucially a certain commerce across the border between the formal and the material, between the ideal and the real. The entanglement of the formal and the material must be thought in itself, apart from or prior to any assimilation into philosophical schemas committed to larger metaphysical claims. This is accomplished in model theory. The twentieth century witnessed two attempts at bringing model theoretical mathematics to bear on accounting philosophically for the concept of truth: that of Alfred Tarski, and that of Alain Badiou. In order to investigate the relevance of model theory to the task of working out a philosophical conception of truth, this dissertation investigates, through comparative work, these two thinkers. It is necessary to see where their projects converge in important ways, as well as where their projects diverge in equally important ways. What brings their work into close proximity is their shared conviction that truth must be thought in light of model theory. Nonetheless, the two do not agree about exactly how model theory sheds light on truth. Comparative study thus reveals both a shared site for thinking and a struggle over the significance of that site. Agreement between Tarski and Badiou concerns the excess of the purely formal over itself, marked by the generation of an undecidable statement within formal systems of a certain level of complexity. Both thinkers determine that this formal excess touches on the material, and both further determine that the consequent entanglement of the formal and the material provides the basic frame for any philosophical consideration
20 CFR 702.333 - Formal hearings; parties.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 20 Employees' Benefits 3 2011-04-01 2011-04-01 false Formal hearings; parties. 702.333 Section 702... Procedures Formal Hearings § 702.333 Formal hearings; parties. (a) The necessary parties for a formal hearing... pursuant to these regulations on behalf of the Director as an interested party....
20 CFR 702.347 - Formal hearings; termination.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 20 Employees' Benefits 3 2011-04-01 2011-04-01 false Formal hearings; termination. 702.347 Section 702.347 Employees' Benefits OFFICE OF WORKERS' COMPENSATION PROGRAMS, DEPARTMENT OF LABOR LONGSHOREMEN... Adjudication Procedures Formal Hearings § 702.347 Formal hearings; termination. (a) Formal hearings...
20 CFR 702.347 - Formal hearings; termination.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 20 Employees' Benefits 4 2013-04-01 2013-04-01 false Formal hearings; termination. 702.347 Section 702.347 Employees' Benefits OFFICE OF WORKERS' COMPENSATION PROGRAMS, DEPARTMENT OF LABOR LONGSHOREMEN... Adjudication Procedures Formal Hearings § 702.347 Formal hearings; termination. (a) Formal hearings...
20 CFR 702.347 - Formal hearings; termination.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 20 Employees' Benefits 4 2014-04-01 2014-04-01 false Formal hearings; termination. 702.347 Section 702.347 Employees' Benefits OFFICE OF WORKERS' COMPENSATION PROGRAMS, DEPARTMENT OF LABOR LONGSHOREMEN... Adjudication Procedures Formal Hearings § 702.347 Formal hearings; termination. (a) Formal hearings...
20 CFR 702.347 - Formal hearings; termination.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 20 Employees' Benefits 4 2012-04-01 2012-04-01 false Formal hearings; termination. 702.347 Section 702.347 Employees' Benefits OFFICE OF WORKERS' COMPENSATION PROGRAMS, DEPARTMENT OF LABOR LONGSHOREMEN... Adjudication Procedures Formal Hearings § 702.347 Formal hearings; termination. (a) Formal hearings...
20 CFR 702.347 - Formal hearings; termination.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Formal hearings; termination. 702.347 Section 702.347 Employees' Benefits EMPLOYMENT STANDARDS ADMINISTRATION, DEPARTMENT OF LABOR LONGSHOREMEN'S... Procedures Formal Hearings § 702.347 Formal hearings; termination. (a) Formal hearings are...
20 CFR 702.336 - Formal hearings; new issues.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Formal hearings; new issues. 702.336 Section... Procedures Formal Hearings § 702.336 Formal hearings; new issues. (a) If, during the course of the formal hearing, the evidence presented warrants consideration of an issue or issues not previously...
Formal concept analysis and linguistic hedges
NASA Astrophysics Data System (ADS)
Belohlavek, Radim; Vychodil, Vilem
2012-07-01
This paper presents an application of linguistic hedges to formal concept analysis of data with fuzzy attributes. Formal concept analysis aims at extraction of particular (bi-)clusters, called formal concepts, from data. The clusters link collections of objects (extents) and attributes (intents), and have a clear interpretation due to a simple verbal description of the concept-forming operators. We insert linguistic hedges such as 'very' or 'extremely' in the description of the operators. In this way, linguistic hedges become parameters for formal concept analysis that control the number of clusters extracted from data. Namely, as we show theoretically as well as experimentally, stronger hedges result in a smaller number of clusters. The new concept-forming operators form Galois-like connections. We study their properties and axiomatize them. Then, we show that a concept lattice with hedges, i.e. the set of all formal concepts of the new operators is indeed a complete lattice which is isomorphic to a particular ordinary concept lattice. We describe the isomorphism and its inverse. These mappings serve as translation procedures. As a consequence, we obtain a theorem characterizing the structure of concept lattices with hedges which generalizes the well-known main theorem of ordinary concept lattices. The isomorphism and its inverse enable us to compute a concept lattice with hedges using algorithms for ordinary concept lattices. We demonstrate by experiments that when selecting various hedges from the strongest to weaker hedges, the reduction in size of the corresponding concept lattices is smooth. From a broader perspective, we argue that linguistic hedges represent mathematically and computationally a feasible way to parameterize methods for knowledge extraction from data that enable one to emphasize or to suppress extracted patterns while keeping their interpretation.
Formal methods demonstration project for space applications
NASA Technical Reports Server (NTRS)
Divito, Ben L.
1995-01-01
The Space Shuttle program is cooperating in a pilot project to apply formal methods to live requirements analysis activities. As one of the larger ongoing shuttle Change Requests (CR's), the Global Positioning System (GPS) CR involves a significant upgrade to the Shuttle's navigation capability. Shuttles are to be outfitted with GPS receivers and the primary avionics software will be enhanced to accept GPS-provided positions and integrate them into navigation calculations. Prior to implementing the CR, requirements analysts at Loral Space Information Systems, the Shuttle software contractor, must scrutinize the CR to identify and resolve any requirements issues. We describe an ongoing task of the Formal Methods Demonstration Project for Space Applications whose goal is to find an effective way to use formal methods in the GPS CR requirements analysis phase. This phase is currently under way and a small team from NASA Langley, ViGYAN Inc. and Loral is now engaged in this task. Background on the GPS CR is provided and an overview of the hardware/software architecture is presented. We outline the approach being taken to formalize the requirements, only a subset of which is being attempted. The approach features the use of the PVS specification language to model 'principal functions', which are major units of Shuttle software. Conventional state machine techniques form the basis of our approach. Given this background, we present interim results based on a snapshot of work in progress. Samples of requirements specifications rendered in PVS are offered to illustration. We walk through a specification sketch for the principal function known as GPS Receiver State processing. Results to date are summarized and feedback from Loral requirements analysts is highlighted. Preliminary data is shown comparing issues detected by the formal methods team versus those detected using existing requirements analysis methods. We conclude by discussing our plan to complete the remaining
NASA Astrophysics Data System (ADS)
Collins, J.; Gamberg, L.; Prokudin, A.; Rogers, T. C.; Sato, N.; Wang, B.
2016-08-01
We construct an improved implementation for combining transverse-momentum-dependent (TMD) factorization and collinear factorization. TMD factorization is suitable for low transverse momentum physics, while collinear factorization is suitable for high transverse momenta and for a cross section integrated over transverse momentum. The result is a modified version of the standard W +Y prescription traditionally used in the Collins-Soper-Sterman (CSS) formalism and related approaches. We further argue that questions regarding the shape and Q dependence of the cross sections at lower Q are largely governed by the matching to the Y term.
Habitat Suitability Index Models: Laughing Gull
Zale, Alexander V.; Mulholland, Rosemarie
1985-01-01
A review and synthesis of existing information were used to develop a habitat model for laughing gull (Larus atricilla). The model is scaled to produce an index of habitat suitability between 0 (unsuitable habitat) and 1.0 (optimally suitable habitat) for areas along the Gulf of Mexico coast. Habitat suitability indices are designed for use with the Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service. Guidelines for application of the model and techniques for measuring model variables are described.
Interpreter composition issues in the formal verification of a processor-memory module
NASA Technical Reports Server (NTRS)
Fura, David A.; Cohen, Gerald C.
1994-01-01
This report describes interpreter composition techniques suitable for the formal specification and verification of a processor-memory module using the HOL theorem proving system. The processor-memory module is a multichip subsystem within a fault-tolerant embedded system under development within the Boeing Defense and Space Group. Modeling and verification methods were developed that permit provably secure composition at the transaction-level of specification, significantly reducing the complexity of the hierarchical verification of the system.
Formal Safety Certification of Aerospace Software
NASA Technical Reports Server (NTRS)
Denney, Ewen; Fischer, Bernd
2005-01-01
In principle, formal methods offer many advantages for aerospace software development: they can help to achieve ultra-high reliability, and they can be used to provide evidence of the reliability claims which can then be subjected to external scrutiny. However, despite years of research and many advances in the underlying formalisms of specification, semantics, and logic, formal methods are not much used in practice. In our opinion this is related to three major shortcomings. First, the application of formal methods is still expensive because they are labor- and knowledge-intensive. Second, they are difficult to scale up to complex systems because they are based on deep mathematical insights about the behavior of the systems (t.e., they rely on the "heroic proof"). Third, the proofs can be difficult to interpret, and typically stand in isolation from the original code. In this paper, we describe a tool for formally demonstrating safety-relevant aspects of aerospace software, which largely circumvents these problems. We focus on safely properties because it has been observed that safety violations such as out-of-bounds memory accesses or use of uninitialized variables constitute the majority of the errors found in the aerospace domain. In our approach, safety means that the program will not violate a set of rules that can range for the simple memory access rules to high-level flight rules. These different safety properties are formalized as different safety policies in Hoare logic, which are then used by a verification condition generator along with the code and logical annotations in order to derive formal safety conditions; these are then proven using an automated theorem prover. Our certification system is currently integrated into a model-based code generation toolset that generates the annotations together with the code. However, this automated formal certification technology is not exclusively constrained to our code generator and could, in principle, also be
ERIC Educational Resources Information Center
Kleis, Russell J.; And Others
The three essays in this discussion paper present ways of structuring the concept of non-formal education. "Toward a Contextual Definition of Non-Formal Education" isolates three primary sub-systems: organizational, human, and curricular. Within these subsets non-formal education is differentiated from formal education by a more loosely integrated…
Habitat suitability index models: Black crappie
Edwards, Elizabeth A.; Krieger, Douglas A.; Bacteller, Mary; Maughan, O. Eugene
1982-01-01
Characteristics and habitat requirements of the black crappie (Pomoxis nigromaculatus) are described in a review of Habitat Suitability Index models. This is one in a series of publications to provide information on the habitat requirements of selected fish and wildlife species. Numerous literature sources have been consulted in an effort to consolidate scientific data on species-habitat relationships. These data have subsequently been synthesized into explicit Habitat Suitability Index (HSI) models. The models are based on suitability indices indicating habitat preferences. Indices have been formulated for variables found to affect the life cycle and survival of each species. Habitat Suitability Index (HSI) models are designed to provide information for use in impact assessment and habitat management activities. The HSI technique is a corollary to the U.S. Fish and Wildlife Service's Habitat Evaluation Procedures.
Habitat Suitability Index Models: Largemouth bass
Stuber, Robert J.; Gebhart, Glen; Maughan, O. Eugene
1982-01-01
This is one of a series of publications that provide information on the habitat requirements of selected fish and wildlife species. Literature describing the relationship between habitat variables related to life requisites and habitat suitability for the Largemouth bass (Micropterus salmoides) are synthesized. These data are subsequently used to develop Habitat Suitability (HIS) models. The HSI models are designed to provide information that can be used in impact assessment and habitat management.
Ling, N.
1989-01-01
A novel formalism, termed Systolic Temporal Arithmetic (STA), is introduced. It provides necessary constructs to describe arithmetic operations in dynamic environments. The motivation behind the development of STA is to use it for systolic array design at the array architecture level. It is particularly useful for formally specifying systolic array designs, and for formally verifying their correctness with respect to the algorithm specifications. Besides providing value and operation abstractions from the lower level, the formalism exploits unique systolic features such as synchrony, regularity, repeatability, modularity, pipelinability, parallel processing ability, as well as spatial and temporal locality, to provide constructs and verification techniques for simple, efficient, and effective systolic array specification verification. STA overcomes many limitations of current specification and verification techniques. It can be used with lower level formalism for multilevel reasoning of systolic arrays. Application examples are given to show how STA can be applied to specify and verify several different systolic arrays. To present a more unified design environment, STA is also extended to describe systolic array synthesis process. A synthesis procedure for systolic arrays is presented which also includes an algorithm transformation technique developed that can improve the computation time of resulting arrays for suitable algorithms, without much increase in area requirement. Several systolic array synthesis examples are also provided in this dissertation.
Formal Methods of V&V of Partial Specifications: An Experience Report
NASA Technical Reports Server (NTRS)
Easterbrook, Steve; Callahan, John
1997-01-01
This paper describes our work exploring the suitability of formal specification methods for independent verification and validation (IV&V) of software specifications for large, safety critical systems. An IV&V contractor often has to perform rapid analysis on incomplete specifications, with no control over how those specifications are represented. Lightweight formal methods show significant promise in this context, as they offer a way of uncovering major errors, without the burden of full proofs of correctness. We describe an experiment in the application of the method SCR. to testing for consistency properties of a partial model of requirements for Fault Detection Isolation and Recovery on the space station. We conclude that the insights gained from formalizing a specification is valuable, and it is the process of formalization, rather than the end product that is important. It was only necessary to build enough of the formal model to test the properties in which we were interested. Maintenance of fidelity between multiple representations of the same requirements (as they evolve) is still a problem, and deserves further study.
Formal verification of medical monitoring software using Z language: a representative sample.
Babamir, Seyed Morteza; Borhani, Mehdi
2012-08-01
Medical monitoring systems are useful aids assisting physicians in keeping patients under constant surveillance; however, taking sound decision by the systems is a physician concern. As a result, verification of the systems behavior in monitoring patients is a matter of significant. The patient monitoring is undertaken by software in modern medical systems; so, software verification of modern medial systems have been noticed. Such verification can be achieved by the Formal Languages having mathematical foundations. Among others, the Z language is a suitable formal language has been used to formal verification of systems. This study aims to present a constructive method to verify a representative sample of a medical system by which the system is visually specified and formally verified against patient constraints stated in Z Language. Exploiting our past experience in formal modeling Continuous Infusion Insulin Pump (CIIP), we think of the CIIP system as a representative sample of medical systems in proposing our present study. The system is responsible for monitoring diabetic's blood sugar.
Formal verification of human-automation interaction
NASA Technical Reports Server (NTRS)
Degani, Asaf; Heymann, Michael
2002-01-01
This paper discusses a formal and rigorous approach to the analysis of operator interaction with machines. It addresses the acute problem of detecting design errors in human-machine interaction and focuses on verifying the correctness of the interaction in complex and automated control systems. The paper describes a systematic methodology for evaluating whether the interface provides the necessary information about the machine to enable the operator to perform a specified task successfully and unambiguously. It also addresses the adequacy of information provided to the user via training material (e.g., user manual) about the machine's behavior. The essentials of the methodology, which can be automated and applied to the verification of large systems, are illustrated by several examples and through a case study of pilot interaction with an autopilot aboard a modern commercial aircraft. The expected application of this methodology is an augmentation and enhancement, by formal verification, of human-automation interfaces.
A Formal Framework for Workflow Analysis
NASA Astrophysics Data System (ADS)
Cravo, Glória
2010-09-01
In this paper we provide a new formal framework to model and analyse workflows. A workflow is the formal definition of a business process that consists in the execution of tasks in order to achieve a certain objective. In our work we describe a workflow as a graph whose vertices represent tasks and the arcs are associated to workflow transitions. Each task has associated an input/output logic operator. This logic operator can be the logical AND (•), the OR (⊗), or the XOR -exclusive-or—(⊕). Moreover, we introduce algebraic concepts in order to completely describe completely the structure of workflows. We also introduce the concept of logical termination. Finally, we provide a necessary and sufficient condition for this property to hold.
Formal Problem Domain Modeling within MDA
NASA Astrophysics Data System (ADS)
Osis, Janis; Asnina, Erika; Grave, Andrejs
The proposed approach called Topological Functioning Modeling for Model Driven Architecture (TFM4MDA) uses formal mathematical foundations of Topological Functioning Model (TFM). It introduces the main feature of MDA - Separation of Concerns by formal analysis of a business system, enables mapping to functional requirements and verifying whether those requirements are in conformity with the TFM of the problem domain. By using a goal-based method, a holistic behavior of the planned application can be decomposed in accordance with the goals. Graph transformation from the TFM to a conceptual model (or a domain object model) enables establishing the definition of domain concepts and their relations. The paper also suggests a concept of a tool for TFM4MDA, which is realized as an Eclipse plug-in.
Hartle formalism for rotating Newtonian configurations
NASA Astrophysics Data System (ADS)
Boshkayev, Kuantay; Quevedo, Hernando; Kalymova, Zhanerke; Zhami, Bakytzhan
2016-11-01
We apply the Hartle formalism to study equilibrium configurations in the framework of Newtonian gravity. This approach allows one to study in a simple manner the properties of the interior gravitational field in the case of static as well as stationary rotating stars in hydrostatic equilibrium. It is shown that the gravitational equilibrium conditions reduce to a system of ordinary differential equations which can be integrated numerically. We derive all the relevant equations up to the second order in the angular velocity. Moreover, we find explicitly the total mass, the moment of inertia, the quadrupole moment, the polar and equatorial radii, the eccentricity and the gravitational binding energy of the rotating body. We also present the procedure to calculate the gravitational Love number. We test the formalism in the case of white dwarfs and show its compatibility with the known results in the literature.
Analyzing phonetic confusions using formal concept analysis.
Peláez-Moreno, C; García-Moral, A I; Valverde-Albacete, F J
2010-09-01
Confusion matrices have been used as a tool for the analysis of speech perception or human speech recognition (HSR) for decades. However, they are rarely employed in automatic speech recognition (ASR) mainly due to the lack of a systematic procedure for their exploration. The generalization of formal concept analysis employed in this paper provides a conceptual interpretation of confusion matrices that enables the analysis of the structure of confusions for both human and machine performances. Generalized formal concept analysis transforms confusion matrices into ordered lattices of confusion events, supporting classic results in HSR that identify a hierarchy of virtual articulatory-acoustic channels. Translating this technique into ASR, a detailed map of the relationships among the speech units employed in the system can be traced to make different sources of confusions apparent: the influence of the lexicon, segmentation errors, dialectal variations or limitations of the feature extraction procedures, among others.
A Formal Basis for Safety Case Patterns
NASA Technical Reports Server (NTRS)
Denney, Ewen; Pai, Ganesh
2013-01-01
By capturing common structures of successful arguments, safety case patterns provide an approach for reusing strategies for reasoning about safety. In the current state of the practice, patterns exist as descriptive specifications with informal semantics, which not only offer little opportunity for more sophisticated usage such as automated instantiation, composition and manipulation, but also impede standardization efforts and tool interoperability. To address these concerns, this paper gives (i) a formal definition for safety case patterns, clarifying both restrictions on the usage of multiplicity and well-founded recursion in structural abstraction, (ii) formal semantics to patterns, and (iii) a generic data model and algorithm for pattern instantiation. We illustrate our contributions by application to a new pattern, the requirements breakdown pattern, which builds upon our previous work
Generalizing Prototype Theory: A Formal Quantum Framework
Aerts, Diederik; Broekaert, Jan; Gabora, Liane; Sozzo, Sandro
2016-01-01
Theories of natural language and concepts have been unable to model the flexibility, creativity, context-dependence, and emergence, exhibited by words, concepts and their combinations. The mathematical formalism of quantum theory has instead been successful in capturing these phenomena such as graded membership, situational meaning, composition of categories, and also more complex decision making situations, which cannot be modeled in traditional probabilistic approaches. We show how a formal quantum approach to concepts and their combinations can provide a powerful extension of prototype theory. We explain how prototypes can interfere in conceptual combinations as a consequence of their contextual interactions, and provide an illustration of this using an intuitive wave-like diagram. This quantum-conceptual approach gives new life to original prototype theory, without however making it a privileged concept theory, as we explain at the end of our paper. PMID:27065436
Generalizing Prototype Theory: A Formal Quantum Framework.
Aerts, Diederik; Broekaert, Jan; Gabora, Liane; Sozzo, Sandro
2016-01-01
Theories of natural language and concepts have been unable to model the flexibility, creativity, context-dependence, and emergence, exhibited by words, concepts and their combinations. The mathematical formalism of quantum theory has instead been successful in capturing these phenomena such as graded membership, situational meaning, composition of categories, and also more complex decision making situations, which cannot be modeled in traditional probabilistic approaches. We show how a formal quantum approach to concepts and their combinations can provide a powerful extension of prototype theory. We explain how prototypes can interfere in conceptual combinations as a consequence of their contextual interactions, and provide an illustration of this using an intuitive wave-like diagram. This quantum-conceptual approach gives new life to original prototype theory, without however making it a privileged concept theory, as we explain at the end of our paper.
Generalizing Prototype Theory: A Formal Quantum Framework.
Aerts, Diederik; Broekaert, Jan; Gabora, Liane; Sozzo, Sandro
2016-01-01
Theories of natural language and concepts have been unable to model the flexibility, creativity, context-dependence, and emergence, exhibited by words, concepts and their combinations. The mathematical formalism of quantum theory has instead been successful in capturing these phenomena such as graded membership, situational meaning, composition of categories, and also more complex decision making situations, which cannot be modeled in traditional probabilistic approaches. We show how a formal quantum approach to concepts and their combinations can provide a powerful extension of prototype theory. We explain how prototypes can interfere in conceptual combinations as a consequence of their contextual interactions, and provide an illustration of this using an intuitive wave-like diagram. This quantum-conceptual approach gives new life to original prototype theory, without however making it a privileged concept theory, as we explain at the end of our paper. PMID:27065436
Formal Definition and Construction of Nominative Signature
NASA Astrophysics Data System (ADS)
Liu, Dennis Y. W.; Wong, Duncan S.; Huang, Xinyi; Wang, Guilin; Huang, Qiong; Mu, Yi; Susilo, Willy
Since the introduction of nominative signature in 1996, there are three problems that have still not been solved. First, there is no convincing application proposed; second, there is no formal security model available; and third, there is no proven secure scheme constructed, given that all the previous schemes have already been found flawed. In this paper, we give positive answers to these problems. First, we illustrate that nominative signature is a better tool for building user certification systems which were originally implemented using universal designated-verifier signature. Second, we propose a formal definition and adversarial model for nominative signature. Third, we show that Chaum's undeniable signature can be transformed to an efficient nominative signature by simply using a standard signature. The security of our transformation can be proven under the standard number-theoretic assumption.
Measurements and mathematical formalism of quantum mechanics
NASA Astrophysics Data System (ADS)
Slavnov, D. A.
2007-03-01
A scheme for constructing quantum mechanics is given that does not have Hilbert space and linear operators as its basic elements. Instead, a version of algebraic approach is considered. Elements of a noncommutative algebra (observables) and functionals on this algebra (elementary states) associated with results of single measurements are used as primary components of the scheme. On the one hand, it is possible to use within the scheme the formalism of the standard (Kolmogorov) probability theory, and, on the other hand, it is possible to reproduce the mathematical formalism of standard quantum mechanics, and to study the limits of its applicability. A short outline is given of the necessary material from the theory of algebras and probability theory. It is described how the mathematical scheme of the paper agrees with the theory of quantum measurements, and avoids quantum paradoxes.
Group adaptation, formal darwinism and contextual analysis.
Okasha, S; Paternotte, C
2012-06-01
We consider the question: under what circumstances can the concept of adaptation be applied to groups, rather than individuals? Gardner and Grafen (2009, J. Evol. Biol.22: 659-671) develop a novel approach to this question, building on Grafen's 'formal Darwinism' project, which defines adaptation in terms of links between evolutionary dynamics and optimization. They conclude that only clonal groups, and to a lesser extent groups in which reproductive competition is repressed, can be considered as adaptive units. We re-examine the conditions under which the selection-optimization links hold at the group level. We focus on an important distinction between two ways of understanding the links, which have different implications regarding group adaptationism. We show how the formal Darwinism approach can be reconciled with G.C. Williams' famous analysis of group adaptation, and we consider the relationships between group adaptation, the Price equation approach to multi-level selection, and the alternative approach based on contextual analysis.
Stochastic Formal Correctness of Numerical Algorithms
NASA Technical Reports Server (NTRS)
Daumas, Marc; Lester, David; Martin-Dorel, Erik; Truffert, Annick
2009-01-01
We provide a framework to bound the probability that accumulated errors were never above a given threshold on numerical algorithms. Such algorithms are used for example in aircraft and nuclear power plants. This report contains simple formulas based on Levy's and Markov's inequalities and it presents a formal theory of random variables with a special focus on producing concrete results. We selected four very common applications that fit in our framework and cover the common practices of systems that evolve for a long time. We compute the number of bits that remain continuously significant in the first two applications with a probability of failure around one out of a billion, where worst case analysis considers that no significant bit remains. We are using PVS as such formal tools force explicit statement of all hypotheses and prevent incorrect uses of theorems.
Flexible receiver adapter formal design review
Krieg, S.A.
1995-06-13
This memo summarizes the results of the Formal (90%) Design Review process and meetings held to evaluate the design of the Flexible Receiver Adapters, support platforms, and associated equipment. The equipment is part of the Flexible Receiver System used to remove, transport, and store long length contaminated equipment and components from both the double and single-shell underground storage tanks at the 200 area tank farms.
Terra in K-16 formal education settings
NASA Astrophysics Data System (ADS)
Chambers, L. H.; Fischer, J. D.; Lewis, P. M.; Moore, S. W.; Oots, P. C.; Rogerson, T. M.; Hitke, K. M.; Riebeek, H.
2009-12-01
Since it began, the Terra mission has had an active presence in formal education at the K-16 level. This educational presence was provided through the S’COOL project for the first five years of the mission, joined by the MY NASA DATA project for the second five years. The Students’ Cloud Observations On-Line (S’COOL) Project, begun in 1997 under the auspices of the Clouds and the Earth’s Radiant Energy System (CERES) project, seeks to motivate students across the entire K-12 spectrum to learn science basics and how they tie in to a larger picture. Beginning early on, college level participants have also participated in the project, both in science classes and in science education coursework. The project uses the connection to an on-going NASA science investigation as a powerful motivator for student observations, analysis and learning, and has reached around the globe as shown in the world map. This poster will review the impact that Terra, through S’COOL, has made in formal education over the last decade. The MY NASA DATA Project began in 2004 under the NASA Research, Education and Applications Solutions Network (REASoN). A 5-year REASoN grant enabled the creation of an extensive website which wraps easily accessible Earth science data - including Terra parameters from CERES (involving MODIS data fusion), MISR, and MOPITT (an example for carbon monoxide is given in the graph, with dark areas indicating high CO levels) - with explanatory material written at the middle school level, and an extensive collection of peer-reviewed lesson plans. The MY NASA DATA site has a rapidly growing user-base and was recently adopted by a number of NASA Earth Science missions, in addition to Terra, as a formal education arm of their Education and Public Outreach efforts. This poster will summarize the contributions that Terra, through MY NASA DATA, has made to formal education since 2004.
Fourth NASA Langley Formal Methods Workshop
NASA Technical Reports Server (NTRS)
Holloway, C. Michael (Compiler); Hayhurst, Kelly J. (Compiler)
1997-01-01
This publication consists of papers presented at NASA Langley Research Center's fourth workshop on the application of formal methods to the design and verification of life-critical systems. Topic considered include: Proving properties of accident; modeling and validating SAFER in VDM-SL; requirement analysis of real-time control systems using PVS; a tabular language for system design; automated deductive verification of parallel systems. Also included is a fundamental hardware design in PVS.
Formalized Epistemology in a Philosophical Perspective
NASA Astrophysics Data System (ADS)
Barreau, Hervé
The need for a formalized epistemology is recognized by all scholars who think that the relativity of all sciences must not be referred to a social relativism. In XXth century, Husserl was the protagonist of such an epistemic philosophy. But this philosophy was more successful in social and human sciences than in natural sciences. In this latter domain, quantum mechanics obeys the requirements of a Kantien perspective in a more precise sense that was the case with Newtonian mechanics.
Toward a Formal Evaluation of Refactorings
NASA Technical Reports Server (NTRS)
Paul, John; Kuzmina, Nadya; Gamboa, Ruben; Caldwell, James
2008-01-01
Refactoring is a software development strategy that characteristically alters the syntactic structure of a program without changing its external behavior [2]. In this talk we present a methodology for extracting formal models from programs in order to evaluate how incremental refactorings affect the verifiability of their structural specifications. We envision that this same technique may be applicable to other types of properties such as those that concern the design and maintenance of safety-critical systems.
[How to write an article: formal aspects].
Corral de la Calle, M A; Encinas de la Iglesia, J
2013-06-01
Scientific research and the publication of the results of the studies go hand in hand. Exquisite research methods can only be adequately reflected in formal publication with the optimum structure. To ensure the success of this process, it is necessary to follow orderly steps, including selecting the journal in which to publish and following the instructions to authors strictly as well as the guidelines elaborated by diverse societies of editors and other institutions. It is also necessary to structure the contents of the article in a logical and attractive way and to use an accurate, clear, and concise style of language. Although not all the authors are directly involved in the actual writing, elaborating a scientific article is a collective undertaking that does not finish until the article is published. This article provides practical advice about formal and not-so-formal details to take into account when writing a scientific article as well as references that will help readers find more information in greater detail.
Extension of Liouville Formalism to Postinstability Dynamics
NASA Technical Reports Server (NTRS)
Zak, Michail
2003-01-01
A mathematical formalism has been developed for predicting the postinstability motions of a dynamic system governed by a system of nonlinear equations and subject to initial conditions. Previously, there was no general method for prediction and mathematical modeling of postinstability behaviors (e.g., chaos and turbulence) in such a system. The formalism of nonlinear dynamics does not afford means to discriminate between stable and unstable motions: an additional stability analysis is necessary for such discrimination. However, an additional stability analysis does not suggest any modifications of a mathematical model that would enable the model to describe postinstability motions efficiently. The most important type of instability that necessitates a postinstability description is associated with positive Lyapunov exponents. Such an instability leads to exponential growth of small errors in initial conditions or, equivalently, exponential divergence of neighboring trajectories. The development of the present formalism was undertaken in an effort to remove positive Lyapunov exponents. The means chosen to accomplish this is coupling of the governing dynamical equations with the corresponding Liouville equation that describes the evolution of the flow of error probability. The underlying idea is to suppress the divergences of different trajectories that correspond to different initial conditions, without affecting a target trajectory, which is one that starts with prescribed initial conditions.
Formalizing Darwinism and inclusive fitness theory
Grafen, Alan
2009-01-01
Inclusive fitness maximization is a basic building block for biological contributions to any theory of the evolution of society. There is a view in mathematical population genetics that nothing is caused to be maximized in the process of natural selection, but this is explained as arising from a misunderstanding about the meaning of fitness maximization. Current theoretical work on inclusive fitness is discussed, with emphasis on the author's ‘formal Darwinism project’. Generally, favourable conclusions are drawn about the validity of assuming fitness maximization, but the need for continuing work is emphasized, along with the possibility that substantive exceptions may be uncovered. The formal Darwinism project aims more ambitiously to represent in a formal mathematical framework the central point of Darwin's Origin of Species, that the mechanical processes of inheritance and reproduction can give rise to the appearance of design, and it is a fitting ambition in Darwin's bicentenary year to capture his most profound discovery in the lingua franca of science. PMID:19805422
Suitability of Varicose Veins for Endovenous Treatments
Goode, S. D.; Kuhan, G.; Altaf, N.; Simpson, R.; Beech, A.; Richards, T.; MacSweeney, S. T.; Braithwaite, B. D.
2009-09-15
The aim of the study was to assess the suitability of radiofrequency ablation (RFA), endovenous laser ablation (EVLA), and foam sclerotherapy (FS) for patients with symptomatic varicose veins (VVs). The study comprised 403 consecutive patients with symptomatic VVs. Data on 577 legs from 403 consecutive patients with symptomatic VVs were collected for the year 2006. Median patient age was 55 years (interquartile range 45-66), and 62% patients were women. A set of criteria based on duplex ultrasonography was used to select patients for each procedure. Great saphenous vein (GSV) reflux was present in 77% (446 of 577) of legs. Overall, 328 (73%) of the legs were suitable for at least one of the endovenous options. Of the 114 legs with recurrent GSV reflux disease, 83 (73%) were suitable to receive endovenous therapy. Patients with increasing age were less likely to be suitable for endovenous therapy (P = 0.03). Seventy-three percent of patients with VVs caused by GSV incompetence are suitable for endovenous therapy.
A Microcomputer-Assisted Presentation of Atomic Orbitals.
ERIC Educational Resources Information Center
Petrich, James A.
1981-01-01
A program written for the Apple II microcomputer that plots the "one-S" orbital of an atom is described. The material is used to move from the Bohr model of the atom to the quantum mechanical description. (MP)
Evaluation of a habitat suitability index model
Farmer, A.H.; Cade, B.S.; Stauffer, D.F.
2002-01-01
We assisted with development of a model for maternity habitat of the Indiana bat (Myotis soda/is), for use in conducting assessments of projects potentially impacting this endangered species. We started with an existing model, modified that model in a workshop, and evaluated the revised model, using data previously collected by others. Our analyses showed that higher indices of habitat suitability were associated with sites where Indiana bats were present and, thus, the model may be useful for identifying suitable habitat. Utility of the model, however, was based on a single component-density of suitable roost trees. Percentage of landscape in forest did not allow differentiation between sites occupied and not occupied by Indiana bats. Moreover, in spite of a general opinion by participants in the workshop that bodies of water were highly productive feeding areas and that a diversity of feeding habitats was optimal, we found no evidence to support either hypothesis.
Habitat Suitability Index Models: Eastern brown pelican
Hingtgen, Terrence M.; Mulholland, Rosemarie; Zale, Alexander V.
1985-01-01
A review and synthesis of existing information were used to develop a habitat model for the eastern brown pelican (Pelecanus occidentalis carolinensis). The model is scaled to produce an index of habitat suitability between 0 (unsuitable habitat) and 1.0 (optimal habitat) for coastal areas within the eastern brown pelican's breeding range. Habitat suitability indices are designed for use with the Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service. Guidelines for application of the eastern brown pelican habitat model and techniques for measuring model variables are described.
Formal specification is an experimental science
Bjorner, D.
1992-09-01
Traditionally, abstract models of large, complex systems have been given in free-form mathematics, combining - often in ad-hoc, not formally supported ways - notions from the disciplines of partial differential equations, functional analysis, mathematical statistics, etc. Such models have been very useful for assimilation of information, analysis (investigation), and prediction (simulation). These models have, however, usually not been helpful in deriving computer representations of the modelled systems - for the purposes of computerized monitoring and control, Computing science, concerned with how to construct objects that can exist within the computer, offers ways of complementing, and in some cases, replacing or combining traditional mathematical models. Formal, model-, as well as property-oriented, specifications in the styles of denotational (respectively, algebraic semantics) represent major approaches to such modelling. In this expository, discursive paper we illustrate what we mean by model-oriented specifications of large, complex technological computing systems. The three modelling examples covers the introvert programming methodological subject of SDEs: software development environments, the distributed computing system subject of wfs`s: (transaction) work flow systems, and the extrovert subject of robots: robotics! the thesis is, just as for mathematical modelling, that we can derive much understanding, etc., from experimentally creating such formally specified models - on paper - and that we gain little in additionally building ad-hoc prototypes. Our models are expressed in a model-oriented style using the VDM specification language Meta-IV In this paper the models only reflect the {open_quotes}data modelling{close_quotes} aspects. We observe that such data models are more easily captured in the model-oriented siyle than in the algebraic semantics property-oriented style which originally was built of the abstraction of operations. 101 refs., 4 figs.
A Formal Mentorship Program for Faculty Development
Le, Jennifer; Nazer, Lama; Hess, Karl; Wang, Jeffrey; Law, Anandi V.
2014-01-01
Objective. To describe the development, implementation, and evaluation of a formal mentorship program at a college of pharmacy. Methods. After extensive review of the mentorship literature within the health sciences, a formal mentorship program was developed between 2006 and 2008 to support and facilitate faculty development. The voluntary program was implemented after mentors received training, and mentors and protégés were matched and received an orientation. Evaluation consisted of conducting annual surveys and focus groups with mentors and protégés. Results. Fifty-one mentor-protégé pairs were formed from 2009 to 2012. A large majority of the mentors (82.8%-96.9%) were satisfied with the mentorship program and its procedures. The majority of the protégés (≥70%) were satisfied with the mentorship program, mentor-protégé relationship, and program logistics. Both mentors and protégés reported that the protégés most needed guidance on time management, prioritization, and work-life balance. While there were no significant improvements in the proteges’ number of grant submissions, retention rates, or success in promotion/tenure, the total number of peer-reviewed publications by junior faculty members was significantly higher after program implementation (mean of 7 per year vs 21 per year, p=0.03) in the college’s pharmacy practice and administration department. Conclusions. A formal mentorship program was successful as measured by self-reported assessments of mentors and protégés. PMID:24954940
Formal Assurance Arguments: A Solution In Search of a Problem?
NASA Technical Reports Server (NTRS)
Graydon, Patrick J.
2015-01-01
An assurance case comprises evidence and argument showing how that evidence supports assurance claims (e.g., about safety or security). It is unsurprising that some computer scientists have proposed formalizing assurance arguments: most associate formality with rigor. But while engineers can sometimes prove that source code refines a formal specification, it is not clear that formalization will improve assurance arguments or that this benefit is worth its cost. For example, formalization might reduce the benefits of argumentation by limiting the audience to people who can read formal logic. In this paper, we present (1) a systematic survey of the literature surrounding formal assurance arguments, (2) an analysis of errors that formalism can help to eliminate, (3) a discussion of existing evidence, and (4) suggestions for experimental work to definitively answer the question.
Formal Aspects of Human-Automation Interaction
NASA Technical Reports Server (NTRS)
Degani, Asaf; Heymann, Michael; Moodi, Michael; Remington, Roger (Technical Monitor)
1998-01-01
While new versions of automated control systems such as flight guidance systems are introduced at a rapid pace, it is widely recognized that user interaction with these machines is increasingly problematic. One cause for this difficulty that is commonly cited in the literature, is the discrepancy between the machine's behavior and the operator's (e.g., pilot) expectations. This paper discusses a formal approach to the analysis of operator's interaction with complex automated control systems. We focus attention on the issue of interface correctness; that is, on the question whether the display provides adequate information about the machine's configurations (states, modes, and associated parameters) and transitions, so as to enable the operator to successfully perform the specified set of tasks. To perform the analysis several assumptions are made: (1) A complete formal model of the machine's behavior is available (e.g., as a state transition system, or as a hybrid-machine); (2) A specification of operator's tasks is available and can be formally described (e.g., the reliable and predictable transition between activities involved in executing a climb to a new altitude); (3) The pilot is well trained and has a correct 'mental' model of the machine's response-map. By 'comparing' the machine's model with the set of operator's tasks we formally (i.e., mathematically) evaluate two questions: 1) does the machine's output interface (display) enable the operator to determine, unambiguously, what the current configuration (e.g., mode) of the machine is, and 2) does the display enable the operator to determine, unambiguously, what the next configuration of the machine will be, in response to a specified interaction by the operator (e.g., engaging a mode or changing a parameter such as a speed or target altitude). This paper describes a methodology for conducting such an evaluation using examples from automated flight control systems of modem 'glass cockpit' jetliners
Progress with Formalization in Medical Informatics?
van der Maas, Arnoud A.F.; Ten Hoopen, A. Johannes; Ter Hofstede, Arthur H.M.
2001-01-01
The prevailing view of medical informatics as a primarily subservient discipline in health care is challenged. Developments in both general informatics and medical informatics are described to identify desirable properties of modeling languages and tools needed to solve key problems in the application field. For progress in medical informatics, it is considered essential to develop far more formal modeling languages, modeling techniques, and tools. A major aim of this development should be to expel ambiguity from concepts essential to medicine, positioning medical informatics “at the heart of health care.” PMID:11230381
The conformal window from the worldline formalism
NASA Astrophysics Data System (ADS)
Armoni, Adi
2010-02-01
We use the worldline formalism to derive a universal relation for the lower boundary of the conformal window in non-supersymmetric QCD-like theories. The derivation relies on the convergence of the expansion of the fermionic determinant in terms of Wilson loops. The expansion shares a similarity with the lattice strong coupling expansion and the genus expansion in string theory. Our result relates the lower boundary of the conformal window in theories with different representations and different gauge groups. Finally, we use SQCD to estimate the boundary of the conformal window in QCD-like theories and compare it with other approaches.
Formal analysis of ORM using OWL DL
NASA Astrophysics Data System (ADS)
Pan, Wen-lin; Liu, Da-xin
2012-01-01
ORM (Object Role Modeling), current version is 2.0, is a fully communication oriented information modeling method. Currently, ORM has been used in ontology engineering to model domain ontologies. To ensure the semantics of ORM model is consistent, it needs using reasoning engines to check semantic conflicts and redundancy. Furthermore, only publish ORM domain ontologies on the Semantic Web described by OWL can it is shared by different applications. Therefore, it needs to map ORM models into OWL DL. Several methods to transform ORM models have been considered and a series of general OWL DL formalization rules have been proposed.
Formal analysis of ORM using OWL DL
NASA Astrophysics Data System (ADS)
Pan, Wen-Lin; Liu, Da-Xin
2011-12-01
ORM (Object Role Modeling), current version is 2.0, is a fully communication oriented information modeling method. Currently, ORM has been used in ontology engineering to model domain ontologies. To ensure the semantics of ORM model is consistent, it needs using reasoning engines to check semantic conflicts and redundancy. Furthermore, only publish ORM domain ontologies on the Semantic Web described by OWL can it is shared by different applications. Therefore, it needs to map ORM models into OWL DL. Several methods to transform ORM models have been considered and a series of general OWL DL formalization rules have been proposed.
BRST and the pure spinor formalism
Garcia, J. Antonio
2008-03-06
The aim of this talk is to show the relation between the standard BRST approach of the GS superstring with the quantization technics used in the pure spinor approach to superstring. To that end we will use the Batalin-Fradkin-Tyutin (BFT) conversion program of second class constraints to first class constraints in the GS superstring using light cone coordinates. By applying this systematic procedure we were able to obtain a gauge system that is equivalent to the recent model proposed in [1] to relate the GS superstring to the pure spinor formalism.
Formal scattering theory by an algebraic approach
NASA Astrophysics Data System (ADS)
Alhassid, Y.; Levine, R. D.
1985-02-01
Formal scattering theory is recast in a Lie-algebraic form. The central result is an algebraic Lippmann-Schwinger equation for the wave operator from which an algebraic form of the Born series (containing only linked terms) is obtained. When a finite Lie algebra is sufficient, The Mo/ller wave operator, on the energy shell, can be solved for explicitly as an element of the corresponding group. The method is illustrated for the separable potential whose relevant algebra is found to be U(1,1).
Formal Verification of Large Software Systems
NASA Technical Reports Server (NTRS)
Yin, Xiang; Knight, John
2010-01-01
We introduce a scalable proof structure to facilitate formal verification of large software systems. In our approach, we mechanically synthesize an abstract specification from the software implementation, match its static operational structure to that of the original specification, and organize the proof as the conjunction of a series of lemmas about the specification structure. By setting up a different lemma for each distinct element and proving each lemma independently, we obtain the important benefit that the proof scales easily for large systems. We present details of the approach and an illustration of its application on a challenge problem from the security domain
Elk habitat suitability map for North Carolina
Williams, Steven G.; Cobb, David T.; Collazo, Jaime
2015-01-01
Although eastern elk (Cervus elaphus canadensis) were extirpated from the eastern United States in the 19th century, they were successfully reintroduced in the North Carolina portion of the Great Smoky Mountains National Park in the early 2000s. The North Carolina Wildlife Resources Commission (NCWRC) is evaluating the prospect of reintroducing the species in other locations in the state to augment recreational opportunities. As a first step in the process, we created a state-wide elk habitat suitability map. We used medium-scale data sets and a two-component approach to iden- tify areas of high biological value for elk and exclude from consideration areas where elk-human conflicts were more likely. Habitats in the state were categorized as 66% unsuitable, 16.7% low, 17% medium, and <1% high suitability for elk. The coastal plain and Piedmont contained the most suitable habitat, but prospective reintroduction sites were largely excluded from consideration due to extensive agricultural activities and pervasiveness of secondary roads. We ranked 31 areas (≥ 500 km2) based on their suitability for reintroduction. The central region of the state contained the top five ranked areas. The Blue Ridge Mountains, where the extant population of elk occurs, was ranked 21st. Our work provides a benchmark for decision makers to evaluate potential consequences and trade-offs associated with the selection of prospective elk reintroduction sites.
24 CFR 581.6 - Suitability criteria.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 24 Housing and Urban Development 3 2010-04-01 2010-04-01 false Suitability criteria. 581.6 Section...) OFFICE OF ASSISTANT SECRETARY FOR COMMUNITY PLANNING AND DEVELOPMENT, DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT COMMUNITY FACILITIES USE OF FEDERAL REAL PROPERTY TO ASSIST THE HOMELESS § 581.6...
24 CFR 581.6 - Suitability criteria.
Code of Federal Regulations, 2013 CFR
2013-04-01
... criteria. (a) All properties, buildings and land will be determined suitable unless a property's... earth slides. (6) Inaccessible. A property that is inaccessible will be determined unsuitable. An... is land locked (e.g., can be reached only by crossing private property and there is no...
24 CFR 581.6 - Suitability criteria.
Code of Federal Regulations, 2012 CFR
2012-04-01
... criteria. (a) All properties, buildings and land will be determined suitable unless a property's... earth slides. (6) Inaccessible. A property that is inaccessible will be determined unsuitable. An... is land locked (e.g., can be reached only by crossing private property and there is no...
45 CFR 12a.6 - Suitability criteria.
Code of Federal Regulations, 2014 CFR
2014-10-01
... ASSIST THE HOMELESS § 12a.6 Suitability criteria. (a) All properties, buildings and land will be... substances such as radon, periodic flooding, sinkholes or earth slides. (6) Inaccessible. A property that is... (including property on small off-shore islands) or is land locked (e.g., can be reached only by...
45 CFR 12a.6 - Suitability criteria.
Code of Federal Regulations, 2013 CFR
2013-10-01
... ASSIST THE HOMELESS § 12a.6 Suitability criteria. (a) All properties, buildings and land will be... substances such as radon, periodic flooding, sinkholes or earth slides. (6) Inaccessible. A property that is... (including property on small off-shore islands) or is land locked (e.g., can be reached only by...
10 CFR 26.63 - Suitable inquiry.
Code of Federal Regulations, 2010 CFR
2010-01-01
... REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Granting and Maintaining Authorization § 26.63 Suitable.... Licensees and other entities may also rely on those licensees' and entities' determinations of fitness that..., and other information that could reflect on the individual's fitness to be granted authorization....
7 CFR 1955.63 - Suitability determination.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 14 2010-01-01 2009-01-01 true Suitability determination. 1955.63 Section 1955.63 Agriculture Regulations of the Department of Agriculture (Continued) RURAL HOUSING SERVICE, RURAL BUSINESS...) PROGRAM REGULATIONS (CONTINUED) PROPERTY MANAGEMENT Management of Property § 1955.63...
24 CFR 3286.405 - Installation suitability.
Code of Federal Regulations, 2010 CFR
2010-04-01
... installation site is protected from surface run-off and can be graded in accordance with part 3285. (b... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Installation suitability. 3286.405 Section 3286.405 Housing and Urban Development Regulations Relating to Housing and Urban...
24 CFR 3286.405 - Installation suitability.
Code of Federal Regulations, 2013 CFR
2013-04-01
... installation site is protected from surface run-off and can be graded in accordance with part 3285. (b... 24 Housing and Urban Development 5 2013-04-01 2013-04-01 false Installation suitability. 3286.405 Section 3286.405 Housing and Urban Development Regulations Relating to Housing and Urban...
24 CFR 3286.405 - Installation suitability.
Code of Federal Regulations, 2012 CFR
2012-04-01
... installation site is protected from surface run-off and can be graded in accordance with part 3285. (b... 24 Housing and Urban Development 5 2012-04-01 2012-04-01 false Installation suitability. 3286.405 Section 3286.405 Housing and Urban Development Regulations Relating to Housing and Urban...
24 CFR 3286.405 - Installation suitability.
Code of Federal Regulations, 2014 CFR
2014-04-01
... installation site is protected from surface run-off and can be graded in accordance with part 3285. (b... 24 Housing and Urban Development 5 2014-04-01 2014-04-01 false Installation suitability. 3286.405 Section 3286.405 Housing and Urban Development Regulations Relating to Housing and Urban...
24 CFR 3286.405 - Installation suitability.
Code of Federal Regulations, 2011 CFR
2011-04-01
... installation site is protected from surface run-off and can be graded in accordance with part 3285. (b... 24 Housing and Urban Development 5 2011-04-01 2011-04-01 false Installation suitability. 3286.405 Section 3286.405 Housing and Urban Development Regulations Relating to Housing and Urban...
10 CFR 26.63 - Suitable inquiry.
Code of Federal Regulations, 2014 CFR
2014-01-01
... REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Granting and Maintaining Authorization § 26.63 Suitable.... Licensees and other entities may also rely on those licensees' and entities' determinations of fitness that..., and other information that could reflect on the individual's fitness to be granted authorization....
10 CFR 26.63 - Suitable inquiry.
Code of Federal Regulations, 2012 CFR
2012-01-01
... REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Granting and Maintaining Authorization § 26.63 Suitable.... Licensees and other entities may also rely on those licensees' and entities' determinations of fitness that..., and other information that could reflect on the individual's fitness to be granted authorization....
10 CFR 26.63 - Suitable inquiry.
Code of Federal Regulations, 2011 CFR
2011-01-01
... REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Granting and Maintaining Authorization § 26.63 Suitable.... Licensees and other entities may also rely on those licensees' and entities' determinations of fitness that..., and other information that could reflect on the individual's fitness to be granted authorization....
10 CFR 26.63 - Suitable inquiry.
Code of Federal Regulations, 2013 CFR
2013-01-01
... REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Granting and Maintaining Authorization § 26.63 Suitable.... Licensees and other entities may also rely on those licensees' and entities' determinations of fitness that..., and other information that could reflect on the individual's fitness to be granted authorization....
20 CFR 702.336 - Formal hearings; new issues.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 20 Employees' Benefits 3 2011-04-01 2011-04-01 false Formal hearings; new issues. 702.336 Section... Adjudication Procedures Formal Hearings § 702.336 Formal hearings; new issues. (a) If, during the course of the... considered, the hearing may be expanded to include the new issue. If in the opinion of the administrative...
Formal-Operational Thinking and the Role of Training.
ERIC Educational Resources Information Center
Wyatt, Mollie L.
Studies exploring the transition from early to middle adolescence have found a significant increase in formal-operational thinking, but it is questionable whether the typical adolescent is capable of consistently applying formal operational logic. To examine the relationship between Piagetian-based training techniques and formal-operational…
"Passing It On": Beyond Formal or Informal Pedagogies
ERIC Educational Resources Information Center
Cain, Tim
2013-01-01
Informal pedagogies are a subject of debate in music education, and there is some evidence of teachers abandoning formal pedagogies in favour of informal ones. This article presents a case of one teacher's formal pedagogy and theorises it by comparing it with a case of informal pedagogy. The comparison reveals affordances of formal pedagogies…
How External Institutions Penetrate Schools through Formal and Informal Leaders
ERIC Educational Resources Information Center
Sun, Min; Frank, Kenneth A.; Penuel, William R.; Kim, Chong Min
2013-01-01
Purposes: This study investigates the role of formal and informal leaders in the diffusion of external reforms into schools and to teachers' practices. Formal leaders are designated by their roles in the formal organization of the school (e.g., principals, department chairs, and instructional coaches) and informal leaders refer to those who…
7 CFR 1726.201 - Formal competitive bidding.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 11 2010-01-01 2010-01-01 false Formal competitive bidding. 1726.201 Section 1726.201... AGRICULTURE ELECTRIC SYSTEM CONSTRUCTION POLICIES AND PROCEDURES Procurement Procedures § 1726.201 Formal competitive bidding. Formal competitive bidding is used for distribution, transmission, and...
Is Lawson's Classroom Test of Formal Reasoning Valid?
ERIC Educational Resources Information Center
Pratt, C.; Hacker, R. G.
1984-01-01
A unidimensional latent trait model was used to test a single-factor hypothesis of the Lawson Classroom Test of Formal Reasoning. The test failed to provide a valid measure of formal reasoning. This was a result of test format which neglected aspects of formal reasoning emphasized by Inhelder and Piaget. (Author/DWH)
25 CFR 151.14 - Formalization of acceptance.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 25 Indians 1 2010-04-01 2010-04-01 false Formalization of acceptance. 151.14 Section 151.14 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER LAND ACQUISITIONS § 151.14 Formalization of acceptance. Formal acceptance of land in trust status shall be accomplished by the issuance...
49 CFR 1111.1 - Content of formal complaints; joinder.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 8 2010-10-01 2010-10-01 false Content of formal complaints; joinder. 1111.1... § 1111.1 Content of formal complaints; joinder. (a) General. A formal complaint must contain the correct... language the facts upon which it is based. It should include specific reference to pertinent...
Integrating Formal Methods and Testing 2002
NASA Technical Reports Server (NTRS)
Cukic, Bojan
2002-01-01
Traditionally, qualitative program verification methodologies and program testing are studied in separate research communities. None of them alone is powerful and practical enough to provide sufficient confidence in ultra-high reliability assessment when used exclusively. Significant advances can be made by accounting not only tho formal verification and program testing. but also the impact of many other standard V&V techniques, in a unified software reliability assessment framework. The first year of this research resulted in the statistical framework that, given the assumptions on the success of the qualitative V&V and QA procedures, significantly reduces the amount of testing needed to confidently assess reliability at so-called high and ultra-high levels (10-4 or higher). The coming years shall address the methodologies to realistically estimate the impacts of various V&V techniques to system reliability and include the impact of operational risk to reliability assessment. Combine formal correctness verification, process and product metrics, and other standard qualitative software assurance methods with statistical testing with the aim of gaining higher confidence in software reliability assessment for high-assurance applications. B) Quantify the impact of these methods on software reliability. C) Demonstrate that accounting for the effectiveness of these methods reduces the number of tests needed to attain certain confidence level. D) Quantify and justify the reliability estimate for systems developed using various methods.
Generalized formalisms of the radio interferometer measurement equation
NASA Astrophysics Data System (ADS)
Price, D. C.; Smirnov, O. M.
2015-05-01
The radio interferometer measurement equation (RIME) is a matrix-based mathematical model that describes the response of a radio interferometer. The Jones calculus it employs is not suitable for describing the analogue components of a telescope. This is because it does not consider the effect of impedance mismatches between components. This paper aims to highlight the limitations of Jones calculus, and suggests some alternative methods that are more applicable. We reformulate the RIME with a different basis that includes magnetic and mixed coherency statistics. We present a microwave network inspired 2N-port version of the RIME, and a tensor formalism based upon the electromagnetic tensor from special relativity. We elucidate the limitations of the Jones-matrix-based RIME for describing analogue components. We show how measured scattering parameters of analogue components can be used in a 2N-port version of the RIME. In addition, we show how motion at relativistic speed affects the observed flux. We present reformulations of the RIME that correctly account for magnetic field coherency. These reformulations extend the standard formulation, highlight its limitations, and may have applications in space-based interferometry and precise absolute calibration experiments.
Detecting Mode Confusion Through Formal Modeling and Analysis
NASA Technical Reports Server (NTRS)
Miller, Steven P.; Potts, James N.
1999-01-01
Aircraft safety has improved steadily over the last few decades. While much of this improvement can be attributed to the introduction of advanced automation in the cockpit, the growing complexity of these systems also increases the potential for the pilots to become confused about what the automation is doing. This phenomenon, often referred to as mode confusion, has been involved in several accidents involving modern aircraft. This report describes an effort by Rockwell Collins and NASA Langley to identify potential sources of mode confusion through two complementary strategies. The first is to create a clear, executable model of the automation, connect it to a simulation of the flight deck, and use this combination to review of the behavior of the automation and the man-machine interface with the designers, pilots, and experts in human factors. The second strategy is to conduct mathematical analyses of the model by translating it into a formal specification suitable for analysis with automated tools. The approach is illustrated by applying it to a hypothetical, but still realistic, example of the mode logic of a Flight Guidance System.
Towards the exploitation of formal methods for information fusion
NASA Astrophysics Data System (ADS)
Clemens, Joachim; Wille, Robert; Schill, Kerstin
2016-05-01
When an autonomous system has to act in or interact with an environment, a suitable representation of it is required. In the past decades, many different representation forms - especially spacial ones - have been proposed and even more information fusion techniques were developed in order to build these representations from multiple information sources. However, most of these algorithms do not exploit the full potential of the available information. This is caused by the fact that they are not able to handle the full complexity of all possible solutions compatible with the information and that they rely on restrictive assumptions (i.e. independencies) in order to make the computation feasible. In this work, a new methodology is envisioned that utilizes formal methods, in particular solvers for Pseudo-Boolean Optimization, to drop some of these assumptions. In order to illustrate the ideas, information fusion based on belief functions and occupancy grid maps are considered. It is shown that this approach allows for considering dependencies among multiple cells and thus significantly reduces the uncertainty in the resulting representation.
Mapping global environmental suitability for Zika virus.
Messina, Jane P; Kraemer, Moritz Ug; Brady, Oliver J; Pigott, David M; Shearer, Freya M; Weiss, Daniel J; Golding, Nick; Ruktanonchai, Corrine W; Gething, Peter W; Cohn, Emily; Brownstein, John S; Khan, Kamran; Tatem, Andrew J; Jaenisch, Thomas; Murray, Christopher Jl; Marinho, Fatima; Scott, Thomas W; Hay, Simon I
2016-01-01
Zika virus was discovered in Uganda in 1947 and is transmitted by Aedes mosquitoes, which also act as vectors for dengue and chikungunya viruses throughout much of the tropical world. In 2007, an outbreak in the Federated States of Micronesia sparked public health concern. In 2013, the virus began to spread across other parts of Oceania and in 2015, a large outbreak in Latin America began in Brazil. Possible associations with microcephaly and Guillain-Barré syndrome observed in this outbreak have raised concerns about continued global spread of Zika virus, prompting its declaration as a Public Health Emergency of International Concern by the World Health Organization. We conducted species distribution modelling to map environmental suitability for Zika. We show a large portion of tropical and sub-tropical regions globally have suitable environmental conditions with over 2.17 billion people inhabiting these areas. PMID:27090089
Mapping global environmental suitability for Zika virus.
Messina, Jane P; Kraemer, Moritz Ug; Brady, Oliver J; Pigott, David M; Shearer, Freya M; Weiss, Daniel J; Golding, Nick; Ruktanonchai, Corrine W; Gething, Peter W; Cohn, Emily; Brownstein, John S; Khan, Kamran; Tatem, Andrew J; Jaenisch, Thomas; Murray, Christopher Jl; Marinho, Fatima; Scott, Thomas W; Hay, Simon I
2016-04-19
Zika virus was discovered in Uganda in 1947 and is transmitted by Aedes mosquitoes, which also act as vectors for dengue and chikungunya viruses throughout much of the tropical world. In 2007, an outbreak in the Federated States of Micronesia sparked public health concern. In 2013, the virus began to spread across other parts of Oceania and in 2015, a large outbreak in Latin America began in Brazil. Possible associations with microcephaly and Guillain-Barré syndrome observed in this outbreak have raised concerns about continued global spread of Zika virus, prompting its declaration as a Public Health Emergency of International Concern by the World Health Organization. We conducted species distribution modelling to map environmental suitability for Zika. We show a large portion of tropical and sub-tropical regions globally have suitable environmental conditions with over 2.17 billion people inhabiting these areas.
Mapping global environmental suitability for Zika virus
Messina, Jane P; Kraemer, Moritz UG; Brady, Oliver J; Pigott, David M; Shearer, Freya M; Weiss, Daniel J; Golding, Nick; Ruktanonchai, Corrine W; Gething, Peter W; Cohn, Emily; Brownstein, John S; Khan, Kamran; Tatem, Andrew J; Jaenisch, Thomas; Murray, Christopher JL; Marinho, Fatima; Scott, Thomas W; Hay, Simon I
2016-01-01
Zika virus was discovered in Uganda in 1947 and is transmitted by Aedes mosquitoes, which also act as vectors for dengue and chikungunya viruses throughout much of the tropical world. In 2007, an outbreak in the Federated States of Micronesia sparked public health concern. In 2013, the virus began to spread across other parts of Oceania and in 2015, a large outbreak in Latin America began in Brazil. Possible associations with microcephaly and Guillain-Barré syndrome observed in this outbreak have raised concerns about continued global spread of Zika virus, prompting its declaration as a Public Health Emergency of International Concern by the World Health Organization. We conducted species distribution modelling to map environmental suitability for Zika. We show a large portion of tropical and sub-tropical regions globally have suitable environmental conditions with over 2.17 billion people inhabiting these areas. DOI: http://dx.doi.org/10.7554/eLife.15272.001 PMID:27090089
ERIC Educational Resources Information Center
Sumida Huaman, Elizabeth; Valdiviezo, Laura Alicia
2014-01-01
In this article, we propose to approach Indigenous education beyond the formal/non-formal dichotomy. We argue that there is a critical need to conscientiously include Indigenous knowledge in education processes from the school to the community; particularly, when formal systems exclude Indigenous cultures and languages. Based on ethnographic…
Guidance for Using Formal Methods in a Certification Context
NASA Technical Reports Server (NTRS)
Brown, Duncan; Delseny, Herve; Hayhurst, Kelly; Wiels, Virginie
2010-01-01
This paper discusses some of the challenges to using formal methods in a certification context and describes the effort by the Formal Methods Subgroup of RTCA SC-205/EUROCAE WG-71 to propose guidance to make the use of formal methods a recognized approach. This guidance, expected to take the form of a Formal Methods Technical Supplement to DO-178C/ED-12C, is described, including the activities that are needed when using formal methods, new or modified objectives with respect to the core DO-178C/ED-12C document, and evidence needed for meeting those objectives.
Habitat Suitability Index Models: Flathead Catfish
Lee, Lawrence A.; Terrell, James W.
1987-01-01
A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the flathead catfish (Pylodictis olivaris). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
Habitat Suitability Index Models: Cactus Wren
Short, Henry L.
1985-01-01
A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the cactus wren (Campylorhynchus brunneicapillus). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
Habitat Suitability Index Models: Eastern Wild Turkey
Schroeder, Richard L.
1985-01-01
A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the eastern wild turkey (Meleagris gallopavo sylvestris). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
Habitat Suitability Index Models: Snapping turtle
Graves, Brent M.; Anderson, Stanley H.
1987-01-01
A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the snapping turtle (Chelydra serpentina). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) and 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
Habitat Suitability Index Models: Marsh wren
Gutzwiller, Kevin J.; Anderson, Stanley H.
1987-01-01
A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the marsh wren (Cistothorus palustris). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
Habitat Suitability Index Models: Spotted owl
Laymon, Stephen A.; Salwasser, Hal; Barrett, Reginald H.
1985-01-01
A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the spotted owl (Strix occidentalis). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
Habitat Suitability Index Models: Cactus wren
Short, Henry L.
1985-01-01
A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the cactus wren (Campylorhynchus brunneicapillus). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
Habitat Suitability Index Models: Swamp rabbit
Allen, Arthur W.
1985-01-01
A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the swamp rabbit (Sylvilagus aquaticus). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
Habitat Suitability Index Models: Eastern wild turkey
Schroeder, Richard L.
1985-01-01
A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the eastern wild turkey (Meleagris gallopavo sylvestris). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
Habitat Suitability Index Models: Hairy Woodpecker
Sousa, Patrick J.
1987-01-01
A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the hairy woodpecker (Picoides villosus). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
Habitat Suitability Index Models: Swamp Rabbit
Allen, Arthur W.
1985-01-01
A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the swamp rabbit (Sylvilagus aquaticus). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
Habitat Suitability Index Models: Slider turtle
Morreale, Stephen J.; Gibbons, J. Whitfield
1986-01-01
A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the slider turtle (Pseudemys scripta). The model consolidates habitat use information into a framework appropriate for field application and is scaled to produce an index between 0.0 (unsuitable habitat) and 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
Habitat Suitability Index Models: Eastern meadowlark
Schroeder, Richard L.; Sousa, Patrick J.
1982-01-01
Habitat preferences of the eastern meadowlark (Sturnella magna) are described in this publication, which is one of a series of Habitat Suitability Index (HSI) models. Habitat use information is presented in a synthesis of the literature on the species-habitat requirements of the eastern meadowlark, followed by the development of the HSI model. The model is presented in three formats: graphic, word, and mathematical, and is designed to provide information for use in impact assessment and habitat management activities.
Habitat Suitability Index Models: Pine warbler
Schroeder, Richard L.
1982-01-01
Habitat preferences of the pine warbler (Dendroica pinus) are described in this publication, which is one of a series of Habitat Suitability Index (HSI) models. Habitat use information is presented in a synthesis of the literature on the species-habitat requirements of the pine warbler, followed by the development of the HSI model. The model is presented in three formats: graphic, word, and mathematical, and is designed to provide information for use in impact assessment and habitat management activities.
Habitat Suitability Index Models: Barred Owl
Allen, Arthur W.
1987-01-01
A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the barred owl (Strix varia). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
Habitat Suitability Index Models: Spotted Owl
Laymon, Stephen A.; Salwasser, Hal; Barrett, Reginald H.
1985-01-01
A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the spotted owl (Strix occidentalis). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
Rethinking Formalisms in Formal Education. Working Paper No. 2005-11
ERIC Educational Resources Information Center
Nathan, Mitchell J.
2005-01-01
In this paper, I explore two beliefs about learning and teaching that I argue are prevalent among educators. The first is the belief that subject matter expertise is sufficient for success in teaching. The second belief is that to learn a specific content area, one needs to begin with an understanding of the formal structure and abstract…
Niche suitability affects development: skull asymmetry increases in less suitable areas.
Maestri, Renan; Fornel, Rodrigo; Galiano, Daniel; de Freitas, Thales R O
2015-01-01
For conservation purposes, it is important to take into account the suitability of a species to particular habitats; this information may predict the long-term survival of a species. In this sense, morphological measures of developmental stress, such as fluctuating asymmetry, can be proxies for an individual's performance in different regions. In this study, we conducted tests to determine whether areas with different levels of suitability for a species (generated by ecological niche models) were congruent with morphological markers that reflect environmental stress and morphological variance. We generated a Maxent niche model and compared the suitability assessments of several areas with the skull morphology data (fluctuating asymmetry and morphological disparity) of populations of the Atlantic forest endemic to Brazil rodent Akodon cursor. Our analyses showed a significant negative relationship between suitability levels and fluctuating asymmetry levels, which indicates that in less suitable areas, the individuals experience numerous disturbances during skull ontogeny. We have not found an association between morphological variance and environmental suitability. As expected, these results suggest that in environments with a lower suitability, developmental stress is increased. Such information is helpful in the understanding of the species evolution and in the selection of priority areas for the conservation of species.
Niche Suitability Affects Development: Skull Asymmetry Increases in Less Suitable Areas
Maestri, Renan; Fornel, Rodrigo; Galiano, Daniel; de Freitas, Thales R. O.
2015-01-01
For conservation purposes, it is important to take into account the suitability of a species to particular habitats; this information may predict the long-term survival of a species. In this sense, morphological measures of developmental stress, such as fluctuating asymmetry, can be proxies for an individual’s performance in different regions. In this study, we conducted tests to determine whether areas with different levels of suitability for a species (generated by ecological niche models) were congruent with morphological markers that reflect environmental stress and morphological variance. We generated a Maxent niche model and compared the suitability assessments of several areas with the skull morphology data (fluctuating asymmetry and morphological disparity) of populations of the Atlantic forest endemic to Brazil rodent Akodon cursor. Our analyses showed a significant negative relationship between suitability levels and fluctuating asymmetry levels, which indicates that in less suitable areas, the individuals experience numerous disturbances during skull ontogeny. We have not found an association between morphological variance and environmental suitability. As expected, these results suggest that in environments with a lower suitability, developmental stress is increased. Such information is helpful in the understanding of the species evolution and in the selection of priority areas for the conservation of species. PMID:25874364
Multilevel structured program design: formalization and applications
Glushkov, V.M.; Tseitlin, G.E.; Yushchenko, E.L.
1981-07-01
The authors present the conception of structured design grammars (SDG), which provide the basis for the MSPD method. A classification of program development methods according to top-down, bottom-up, and mixed strategy is proposed. The SDG formalism makes it possible to consider the problem of multilevel partial program verification, program transformation, and documentation generation during program development and subsequent maintenance. The MSPD method is demonstrated in application to a number of program design projects. They develop the arsenal of structured programming using MSPD method. Language and software tools constituting the basis of structured programming are considered. The problem of multilevel optimizing translation is treated in the context of the mul'tiprotsessist system oriented to automatic structured parallel programming by the MSPD method. Applications of the MSPD method to symbolic processing are considered. The process of structured design of the partran system and of software modules for mini- and microcomputers is described. 70 references.
Formalization of Embodied Sensorimotor Coupling System
NASA Astrophysics Data System (ADS)
Nakajima, Kohei
2008-10-01
Theoretical conception of an active behavior of the system is one of the most challengeable topics in complex systems research. Recently, especially in the fields of robotics and artificial intelligence, there broadly exists the study to understand the interface between the system and its environment by creating an autonomous agent that carries a sensorimotor coupling. In this paper, an embodied sensorimotor coupling system is discussed. Applying a generative pointer, the system is formalized to contain an intrinsic discrepancy induced by heterarichical duality in a flow construction by using category theory. In the system, the body plays a positive role as a dynamical mediator, or interface, between two conflicting layers, a relational layers and a constituent layers. As a result, it induces a structural change of the system itself. Implementing the construction to a Braitenberg type vehicle, we observed dynamical changes of system parameters and its behavior revealed various motion patterns compared with the conventional sensorimotor coupling system.
Formalizing Linguistic Conventions for Conceptual Models
NASA Astrophysics Data System (ADS)
Becker, Jörg; Delfmann, Patrick; Herwig, Sebastian; Lis, Łukasz; Stein, Armin
A precondition for the appropriate analysis of conceptual models is not only their syntactic correctness but also their semantic comparability. Assuring comparability is challenging especially when models are developed by different persons. Empirical studies show that such models can vary heavily, especially in model element naming, even if they express the same issue. In contrast to most ontology-driven approaches proposing the resolution of these differences ex-post, we introduce an approach that avoids naming differences in conceptual models already during modeling. Therefore we formalize naming conventions combining domain thesauri and phrase structures based on a lin-guistic grammar. This allows for guiding modelers automatically during the modeling process using standardized labels for model elements. Our approach is generic, making it applicable for any modeling language.
A formal language for computational systems biology.
Errampalli, Daniel D; Priami, Corrado; Quaglia, Paola
2004-01-01
The post-genomic era has opened new insights into the complex biochemical reaction systems present in the cell and has generated huge amount of information. The biological systems are highly complex and can overwhelm the numerically computable models. Therefore, models employing symbolical techniques might provide a faster insight. This paper presents some preliminary results and recent trends in the above direction. Specifically, it presents an overview of the main features of some formalisms and techniques from the field of specification languages for concurrency and mobility, which have been proposed to model and simulate the dynamics of the interaction of complex biological systems. The ultimate goal of these symbolic approaches is the modeling, analysis, simulation, and hopefully prediction of the behavior of biological systems (vs. biological components).
Systolic temporal arithmetic; A new formalism for specification and verification of systolic arrays
Ling, N. ); Bayoumi, M.A. )
1990-08-01
This paper introduces a novel formalism named systolic temporal arithmetic (STA) suitable for describing arithmetic operations in dynamic environments. The motivation behind the development of STA is to use it for formal specifications and verifications of systolic arrays at the array architecture level. Besides providing value and operation abstraction from the lower level, it also exploits several features of systolic arrays such as synchrony, regularity, repeatability, modularity, pipelinability, parallel processing ability, as well as spatial and temporal locality. STA provides constructs and verification techniques for simple, efficient, and effective systolic array specification and verification. Verification techniques such as mathematical induction are suggested to exploit these systolic array features so as to speedup the process.
A very general electromagnetic gyrokinetic formalism
NASA Astrophysics Data System (ADS)
McMillan, B. F.; Sharma, A.
2016-09-01
We derive a gyrokinetic formalism which is very generally valid: the ordering allows both large inhomogeneities in plasma flow and magnetic field at long wavelength, such as typical drift-kinetic theories, as well as fluctuations at the gyro-scale. The underlying approach is to order the vorticity to be small, and to assert that the timescales in the local plasma frame are long compared to the gyrofrequency. Unlike most other derivations, we do not treat the long and short wavelength components of the fluctuating fields separately; the single-field description defines the particle motion and their interaction with the electromagnetic field at small-scale, the system-scale, and intermediate length scales in a unified fashion. As in earlier literature, the work consists of identifying a coordinate system where the gyroangle-dependent terms are small, and using a near-unity transform to systematically find a set of coordinates where the gyroangle dependence vanishes. We derive a gyrokinetic Lagrangian which is valid where the vorticity | ∇ × ( E × B / B ) | is small compared to the gyrofrequency Ω, and the magnetic field scale length is long compared to the gyroradius; we also require that time variation be slow in an appropriately chosen reference frame. This appears to be a minimum set of constraints on a gyrokinetic theory and is substantially more general than earlier approaches. It is the general-geometry electromagnetic extension of Dimits, Phys. Plasmas 17, 055901 (2010) (which is an electrostatic formalism with a homogeneous background magnetic field). This approach also does not require a separate treatment of fluctuating and background components of the magnetic field, unlike much of the previous literature. As a consequence, the "cross terms" due to a combination of long- and short-wavelength variation, which were ignored in the earlier work (but derived in a more restrictive ordering in Parra and Calvo, Plasma Phys. Controlled Fusion 53, 045001 (2011
Spatial Experiment Technologies Suitable for Unreturnable Bioreactor
NASA Astrophysics Data System (ADS)
Zhang, Tao; Zheng, Weibo; Tong, Guanghui
2016-07-01
The system composition and main function of the bioreactor piggybacked on TZ cargo transport spacecraft are introduced briefly in the paper.The spatial experiment technologies which are suitable for unreturnable bioreactor are described in detail,including multi-channel liquid transportion and management,multi-type animal cells circuit testing,dynamic targets microscopic observation in situ etc..The feasibility and effectiveness of these technologies which will be used in space experiment in bioreactor are verified in tests and experiments on the ground.
Habitat Suitability Index Models: Red king crab
Jewett, Stephen C.; Onuf, Christopher P.
1988-01-01
A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for evaluating habitat of different life stages of red king crab (Paralithodes camtschatica). A model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) and 1.0 (optimum habitat) in Alaskan coastal waters, especially in the Gulf of Alaska and the southeastern Bering Sea. HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
Habitat Suitability Index Models and Instream Flow Suitability Curves: Chum Salmon
Hale, Stephen S.; McMahon, Thomas E.; Nelson, Patrick C.
1985-01-01
A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model and instream flow suitability curves for the chum salmon (Oncorhynchus keta). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
Habitat Suitability Index Models and Instream Flow Suitability Curves: Pink salmon
Raleigh, Robert F.; Nelson, Patrick C.
1985-01-01
A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model and instream flow suitability curves for the pink salmon (Oncorhynchus gorbuscha). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
Habitat Suitability Index Models and Instream Flow Suitability Curves: Chum salmon
Hale, Stephen S.; McMahon, Thomas E.; Nelson, Patrick C.
1985-01-01
A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model and instream flow suitability curves for the chum salmon (Oncorhynchus keta). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
Application of a new dosimetry formalism to volumetric modulated arc therapy (VMAT)
NASA Astrophysics Data System (ADS)
Rosser, Karen E.; Bedford, James L.
2009-12-01
Volumetric modulated arc therapy (VMAT) offers a challenge to classical dosimetry protocols as the beams are dynamic in orientation and aperture shape and may include small apertures. The aim of this paper is to apply a formalism to VMAT beams that has recently been published by the International Atomic Energy Agency (IAEA) working party to improve the dosimetry for small and non-standard fields. We investigated three possible fields and assessed their suitability as plan class specific reference (pcsr) fields. The factors in the new dosimetry formalism were investigated: the conversion of dose to water from the conventional reference field to the pcsr and then from the pcsr to a treatment plan, using a PTW semiflex chamber, two Farmer chambers and an electron diode. Finally, the dose was compared for Alanine, the new formalism and calculated using Pinnacle3 (Philips Radiation Oncology Systems) for two typical clinical VMAT beams. Correction factors between the reference field and the pcsr determined with Alanine range from 0.1% to 2.3% for the three pcsr fields. Dose to water measured using the calibrated ionization chambers is less than 2% different to the dose calculated by Pinnacle3. VMAT planning and delivery procedures have been successfully implemented and a new dosimetry protocol has been investigated for this new technique. Calibration factors for pcsr fields are found to be up to 2.3% different when using the new formalism, compared to using a standard dosimetry protocol. Using the calibration factors determined in the pcsr fields, the ionization chambers and electron diode agree to within 1% with Alanine dosimetry for two clinical VMAT plans. Good agreements between calculations and measurements are found for these two plans when the new formalism is used.
The probability of finding suitable directed donors.
Kanter, M; Selvin, S; Myhre, B A
1989-02-01
A series of tables based on mathematical calculations is given as guidelines for the number of directed donors needed by members of various ethnic/racial groups to provide a desired number of units of blood with a selected probability of achieving this result. From these tables, certain conclusions can be drawn. Unrelated donors who do not know their blood type are an inefficient source of directed donors. Rh-negative patients are unlikely to obtain enough directed-donor units from either related or unrelated donors with confidence unless these donors known their blood type. In general, siblings, parents, and offspring are the most efficient directed donors from the standpoint of compatibility. Cousins, uncles, aunts, nieces, and nephews are not much more likely to be compatible than unrelated donors are. It is easier to obtain suitable directed-donor units among Hispanics than among whites, blacks, or Asians, due to their skewed blood group frequencies. In general, using O-negative directed donors for Rh-positive recipients does not significantly increase the likelihood of finding suitable donors.
A passive radon dosemeter suitable for workplaces.
Orlando, C; Orland, P; Patrizii, L; Tommasino, L; Tonnarini, S; Trevisi, R; Viola, P
2002-01-01
The results obtained in different international intercomparisons on passive radon monitors have been analysed with the aim of identifying a suitable radon monitoring device for workplaces. From this analysis, the passive radon device, first developed for personal dosimetry in mines by the National Radiation Protection Board, UK (NRPB), has shown the most suitable set of characteristics. This radon monitor consists of a diffusion chamber, made of conductive plastic with less than 2 cm height, containing a CR-39 film (Columbia Resin 1939), as track detector. Radon detectors in workplaces may be exposed only during the working hours, thus requiring the storage of the detectors in low-radon zones when not exposed. This paper describes how this problem can be solved. Since track detectors are also efficient neutron dosemeters, care should be taken when radon monitors are used in workplaces, where they may he exposed to neutrons, such as on high altitude mountains, in the surroundings of high energy X ray facilities (where neutrons are produced by (gamma, n) reactions) or around high energy particle accelerators. To this end, the response of these passive radon monitors to high energy neutron fields has been investigated. PMID:12408493
Collins, J.; Gamberg, L.; Prokudin, A.; Rogers, T. C.; Sato, N.; Wang, B.
2016-08-08
We construct an improved implementation for combining TMD factorization transverse- momentum-dependent (TMD) factorization and collinear factorization. TMD factorization is suit- able for low transverse momentum physics, while collinear factorization is suitable for high transverse momenta and for a cross section integrated over transverse momentum. The result is a modified version of the standard W + Y prescription traditionally used in the Collins-Soper-Sterman (CSS) formalism and related approaches. As a result, we further argue that questions regarding the shape and Q- dependence of the cross sections at lower Q are largely governed by the matching to the Y -term.
NASA Technical Reports Server (NTRS)
Tilmes, Curt
2014-01-01
The Global Change Information System (GCIS) provides a framework for the formal representation of structured metadata about data and information about global change. The pilot deployment of the system supports the National Climate Assessment (NCA), a major report of the U.S. Global Change Research Program (USGCRP). A consumer of that report can use the system to browse and explore that supporting information. Additionally, capturing that information into a structured data model and presenting it in standard formats through well defined open inter- faces, including query interfaces suitable for data mining and linking with other databases, the information becomes valuable for other analytic uses as well.
Connecting Formal and Informal Learning Experiences
NASA Astrophysics Data System (ADS)
O'Mahony, Timothy Kieran
The learning study reports on part of a larger project being lead by the author. In this dissertation I explore one goal of this project---to understand effects on student learning outcomes as a function of using different methods for connecting out-of-school experiential learning with formal school-based instruction. There is a long history of assuming that "experience is the best teacher"(e.g. Aristotle, 360 BC; Dewey, 1934; Kolb, 1997; Pliny, AD 77). As a practical geographer I endorsed that assumption throughout my teaching career, paying attention to local topography, physical features, and natural resources in the geographic hinterland. I was particularly interested in understanding the impact of the physical landscape on humankind, and reciprocally, noting humankind's widespread impressions on the natural world. Until I began this research project, I assumed that everyone else paid a similar attention to immediate surroundings. The work that I describe in this dissertation emerges out of a conviction that there are many degrees of truth to the idea that experience is a great teacher. Its effectiveness seems to depend on how one's "experience" is mediated, and how "learning from it" is defined. This motivated me to think about design principles for linking people's experiences to learning. I began to explore, experimentally, how I might enhance people's abilities to notice, represent, and discuss their experiences in order to better learn from them. This study investigated how different ways of connecting outdoor learning experiences to formal schooling impacts students' performance. I studied high-school students in outdoor settings as they engaged in evocative issues of learning pertaining to consequential everyday life encounters. Different kinds of "expert mediation" were introduced and tested as the students engaged in investigative activities around the science of dam removal and habitat restoration. I measured outcomes with the aid of pre- and
Formal verification of an oral messages algorithm for interactive consistency
NASA Technical Reports Server (NTRS)
Rushby, John
1992-01-01
The formal specification and verification of an algorithm for Interactive Consistency based on the Oral Messages algorithm for Byzantine Agreement is described. We compare our treatment with that of Bevier and Young, who presented a formal specification and verification for a very similar algorithm. Unlike Bevier and Young, who observed that 'the invariant maintained in the recursive subcases of the algorithm is significantly more complicated than is suggested by the published proof' and who found its formal verification 'a fairly difficult exercise in mechanical theorem proving,' our treatment is very close to the previously published analysis of the algorithm, and our formal specification and verification are straightforward. This example illustrates how delicate choices in the formulation of the problem can have significant impact on the readability of its formal specification and on the tractability of its formal verification.
Formal Methods Applications in Air Transportation
NASA Technical Reports Server (NTRS)
Farley, Todd
2009-01-01
The U.S. air transportation system is the most productive in the world, moving far more people and goods than any other. It is also the safest system in the world, thanks in part to its venerable air traffic control system. But as demand for air travel continues to grow, the air traffic control system s aging infrastructure and labor-intensive procedures are impinging on its ability to keep pace with demand. And that impinges on the growth of our economy. Air traffic control modernization has long held the promise of a more efficient air transportation system. Part of NASA s current mission is to develop advanced automation and operational concepts that will expand the capacity of our national airspace system while still maintaining its excellent record for safety. It is a challenging mission, as efforts to modernize have, for decades, been hamstrung by the inability to assure safety to the satisfaction of system operators, system regulators, and/or the traveling public. In this talk, we ll provide a brief history of air traffic control, focusing on the tension between efficiency and safety assurance, and the promise of formal methods going forward.
Fostering Formal Commutativity Knowledge with Approximate Arithmetic.
Hansen, Sonja Maria; Haider, Hilde; Eichler, Alexandra; Godau, Claudia; Frensch, Peter A; Gaschler, Robert
2015-01-01
How can we enhance the understanding of abstract mathematical principles in elementary school? Different studies found out that nonsymbolic estimation could foster subsequent exact number processing and simple arithmetic. Taking the commutativity principle as a test case, we investigated if the approximate calculation of symbolic commutative quantities can also alter the access to procedural and conceptual knowledge of a more abstract arithmetic principle. Experiment 1 tested first graders who had not been instructed about commutativity in school yet. Approximate calculation with symbolic quantities positively influenced the use of commutativity-based shortcuts in formal arithmetic. We replicated this finding with older first graders (Experiment 2) and third graders (Experiment 3). Despite the positive effect of approximation on the spontaneous application of commutativity-based shortcuts in arithmetic problems, we found no comparable impact on the application of conceptual knowledge of the commutativity principle. Overall, our results show that the usage of a specific arithmetic principle can benefit from approximation. However, the findings also suggest that the correct use of certain procedures does not always imply conceptual understanding. Rather, the conceptual understanding of commutativity seems to lag behind procedural proficiency during elementary school. PMID:26560311
An enantioselective formal synthesis of montelukast sodium.
Bollikonda, Satyanarayana; Mohanarangam, Saravanan; Jinna, Rajender Reddy; Kandirelli, Venkata Kiran Kumar; Makthala, Laxman; Sen, Saikat; Chaplin, David A; Lloyd, Richard C; Mahoney, Thomas; Dahanukar, Vilas Hareshwar; Oruganti, Srinivas; Fox, Martin E
2015-04-17
A formal synthesis of the antiasthma drug montelukast sodium is described, wherein the key chiral diol intermediate was accessed with greater convergence of the C-C bond-forming steps as compared to previous routes. Improved synthetic efficiency was achieved by deploying homogeneous metal-based catalysis in two pivotal steps. In the first, a tandem Mizoroki-Heck reaction and double-bond isomerization between a previously known allyl alcohol intermediate and a hindered 2-(2-halophenyl)propan-2-ol secured direct access to the 3-(2-(2-hydroxypropan-2-yl)phenyl)-1-phenylpropan-1-one moiety in the product. In the second step, asymmetric hydrogenation of the ketone functionality in the Mizoroki-Heck reaction product provided a convenient method to introduce the benzylic alcohol chiral center and obtain the desired chiral diol precursor of montelukast sodium. A detailed catalyst screening led to the identification of ((R)-Xyl-BINAP)((R,R)-DPEN)RuCl2 as a catalyst that afforded an enantioselectivity of 99% ee in the hydrogenation step on a multigram lab scale at a molar substrate:catalyst loading of 5000:1. PMID:25807000
Fostering Formal Commutativity Knowledge with Approximate Arithmetic
Hansen, Sonja Maria; Haider, Hilde; Eichler, Alexandra; Godau, Claudia; Frensch, Peter A.; Gaschler, Robert
2015-01-01
How can we enhance the understanding of abstract mathematical principles in elementary school? Different studies found out that nonsymbolic estimation could foster subsequent exact number processing and simple arithmetic. Taking the commutativity principle as a test case, we investigated if the approximate calculation of symbolic commutative quantities can also alter the access to procedural and conceptual knowledge of a more abstract arithmetic principle. Experiment 1 tested first graders who had not been instructed about commutativity in school yet. Approximate calculation with symbolic quantities positively influenced the use of commutativity-based shortcuts in formal arithmetic. We replicated this finding with older first graders (Experiment 2) and third graders (Experiment 3). Despite the positive effect of approximation on the spontaneous application of commutativity-based shortcuts in arithmetic problems, we found no comparable impact on the application of conceptual knowledge of the commutativity principle. Overall, our results show that the usage of a specific arithmetic principle can benefit from approximation. However, the findings also suggest that the correct use of certain procedures does not always imply conceptual understanding. Rather, the conceptual understanding of commutativity seems to lag behind procedural proficiency during elementary school. PMID:26560311
A Hamilton Jacobi formalism for thermodynamics
NASA Astrophysics Data System (ADS)
Rajeev, S. G.
2008-09-01
We show that classical thermodynamics has a formulation in terms of Hamilton-Jacobi theory, analogous to mechanics. Even though the thermodynamic variables come in conjugate pairs such as pressure/volume or temperature/entropy, the phase space is odd-dimensional. For a system with n thermodynamic degrees of freedom it is 2n+1-dimensional. The equations of state of a substance pick out an n-dimensional submanifold. A family of substances whose equations of state depend on n parameters define a hypersurface of co-dimension one. This can be described by the vanishing of a function which plays the role of a Hamiltonian. The ordinary differential equations (characteristic equations) defined by this function describe a dynamical system on the hypersurface. Its orbits can be used to reconstruct the equations of state. The 'time' variable associated to this dynamics is related to, but is not identical to, entropy. After developing this formalism on well-grounded systems such as the van der Waals gases and the Curie-Weiss magnets, we derive a Hamilton-Jacobi equation for black hole thermodynamics in General Relativity. The cosmological constant appears as a constant of integration in this picture.
Formal policies for flexible EHR security.
Blobel, Bernd; Pharow, Peter
2006-01-01
State of the Art methodologies for establishing requirements and solutions to securing applications are based on narrative descriptions about the use of available system, sometimes also dedicated to system components. Even nowadays new developments to ruling application security services by the use of predicate logic suffer from being administered manually. Therefore, security and privacy requirements cannot be properly met resulting in restrictions and fears for allowing the use of sensitive data and functions. Because of the sensitivity of personal health information and especially of genetic data with its wider implications beyond the original subject of care, weaknesses in guaranteeing fine-grained security and privacy rules lead to less acceptance or even the avoidance of essential information transfer and use. To overcome the problem, security and privacy have to become properties of the architectural components of the respective health information system. Embedding security into the systems architecture allows for negotiating and enforcing any security and privacy services related to principals, their roles, their relationships, further contextual information as well as other regulations summarized in formally modeled policies. The paper introduces the evolving paradigm of the model-driven architecture, first time also comprehensively deployed for security and privacy services in bio-genetic and health information systems.
The Lagrangian-Hamiltonian formalism for higher order field theories
NASA Astrophysics Data System (ADS)
Vitagliano, Luca
2010-06-01
We generalize the Lagrangian-Hamiltonian formalism of Skinner and Rusk to higher order field theories on fiber bundles. As a byproduct we solve the long standing problem of defining, in a coordinate free manner, a Hamiltonian formalism for higher order Lagrangian field theories. Namely, our formalism does only depend on the action functional and, therefore, unlike previously proposed ones, is free from any relevant ambiguity.
A formalism for the calculus of variations with spinors
NASA Astrophysics Data System (ADS)
Bäckdahl, Thomas; Valiente Kroon, Juan A.
2016-02-01
We develop a frame and dyad gauge-independent formalism for the calculus of variations of functionals involving spinorial objects. As a part of this formalism, we define a modified variation operator which absorbs frame and spin dyad gauge terms. This formalism is applicable to both the standard spacetime (i.e., SL(2, ℂ)) 2-spinors as well as to space (i.e., SU(2, ℂ)) 2-spinors. We compute expressions for the variations of the connection and the curvature spinors.
Stability formalism of a flowing two-fluid plasma
NASA Astrophysics Data System (ADS)
Yamada, Hideaki; Katano, Takayuki; Ishida, Akio; Steinhauer, Loren C.
2003-04-01
An improved formalism for a stability analysis of flowing two-fluid equilibria with constant density is developed. The two-fluid formalism, in which the generalized vorticity of each species is introduced as characteristic quantity, extends the usual single-fluid formalism. A new relation between the perturbed generalized vorticity and the displacement is found for each species. The spectral formalism is developed for stability of axisymmetric equilibrium. The missing elements in the single-fluid analysis of Frieman and Rotenberg [Rev. Mod. Phys. 32, 898 (1960)] are identified.
A Formal Semantics for the SRI Hierarchical Program Design Methodology
NASA Technical Reports Server (NTRS)
Boyer, R. S.; Moore, J. S.
1983-01-01
A formal statement of what it means to use (a subset of) the methodology is presented. It is formally defined that some specified module exists and what it means to say that another module is paid correctly implemented on top of it. No attention is to motivation, either of the methodology or of the formal development of it. Concentration is entirely upon mathematical succinctness and precision. A discussion is presented of how to use certain INTERLISP programs which implement the formal definitions. Among these are a program which generates Floyd like verification conditions sufficient to imply the correctness of a module implementation.
Formal Specification of the OpenMP Memory Model
Bronevetsky, G; de Supinski, B R
2006-05-17
OpenMP [1] is an important API for shared memory programming, combining shared memory's potential for performance with a simple programming interface. Unfortunately, OpenMP lacks a critical tool for demonstrating whether programs are correct: a formal memory model. Instead, the current official definition of the OpenMP memory model (the OpenMP 2.5 specification [1]) is in terms of informal prose. As a result, it is impossible to verify OpenMP applications formally since the prose does not provide a formal consistency model that precisely describes how reads and writes on different threads interact. This paper focuses on the formal verification of OpenMP programs through a proposed formal memory model that is derived from the existing prose model [1]. Our formalization provides a two-step process to verify whether an observed OpenMP execution is conformant. In addition to this formalization, our contributions include a discussion of ambiguities in the current prose-based memory model description. Although our formal model may not capture the current informal memory model perfectly, in part due to these ambiguities, our model reflects our understanding of the informal model's intent. We conclude with several examples that may indicate areas of the OpenMP memory model that need further refinement however it is specified. Our goal is to motivate the OpenMP community to adopt those refinements eventually, ideally through a formal model, in later OpenMP specifications.
Habitat Suitability Index Models: Ferruginous hawk
Jasikoff, Thomas M.
1982-01-01
The ferruginous hawk inhabits grasslands, shrublands, and steppe-deserts of the Western United States. It is a common nester in Colorado, Idaho, Montana, Utah, and Wyoming (Call 1978). Populations in the more Northern States tend to be migratory, spending the winter in New Mexico, Colorado, Kansas, Texas, and Oklahoma (Call 1979).Ferruginous hawks thrive in areas that favor the production of rabbits (Lagomorpha), prairie dogs (Cynomys spp.), or ground squirrels (Citellus spp. and Spermophilus spp.) (Call 1979), provided that suitable nesting sites are available. Foraging habitat consists of nonforested, nonmountainous areas, such as desert shrub and grassland communities. Nesting habitat consists of communities with isolated trees, woodland edges, buttes, cliffs, and/or grassland with some relief.
Formal education and back pain: a review
Dionne, C; Von Korff, M; Koepsell, T; Deyo, R; Barlow, W; Checkoway, H
2001-01-01
OBJECTIVES—To summarise the scientific evidence on the relation between educational status and measures of the frequency and the consequences of back pain and of the outcomes of interventions among back pain patients, and to outline possible mechanisms that could explain such an association if found. DESIGN—Sixty four articles published between 1966 and 2000 that documented the association of formal education with back pain were reviewed. MAIN RESULTS—Overall, the current available evidence points indirectly to a stronger association of low education with longer duration and/or higher recurrence of back pain than to an association with onset. The many reports of an association of low education with adverse consequences of back pain also suggest that the course of a back pain episode is less favourable among persons with low educational attainment. Mechanisms that could explain these associations include variations in behavioural and environmental risk factors by educational status, differences in occupational factors, compromised "health stock" among people with low education, differences in access to and utilisation of health services, and adaptation to stress. Although lower education was not associated with the outcomes of interventions in major studies, it is difficult, in light of the current limited available evidence, to draw firm conclusions on this association. CONCLUSION—Scientific evidence supports the hypothesis that less well educated people are more likely to be affected by disabling back pain. Further study of this association may help advance our understanding of back pain as well as understanding of the relation between socioeconomic status and disease as a general phenomenon. Keywords: back pain; educational status PMID:11413174
A formal model of interpersonal inference
Moutoussis, Michael; Trujillo-Barreto, Nelson J.; El-Deredy, Wael; Dolan, Raymond J.; Friston, Karl J.
2014-01-01
Introduction: We propose that active Bayesian inference—a general framework for decision-making—can equally be applied to interpersonal exchanges. Social cognition, however, entails special challenges. We address these challenges through a novel formulation of a formal model and demonstrate its psychological significance. Method: We review relevant literature, especially with regards to interpersonal representations, formulate a mathematical model and present a simulation study. The model accommodates normative models from utility theory and places them within the broader setting of Bayesian inference. Crucially, we endow people's prior beliefs, into which utilities are absorbed, with preferences of self and others. The simulation illustrates the model's dynamics and furnishes elementary predictions of the theory. Results: (1) Because beliefs about self and others inform both the desirability and plausibility of outcomes, in this framework interpersonal representations become beliefs that have to be actively inferred. This inference, akin to “mentalizing” in the psychological literature, is based upon the outcomes of interpersonal exchanges. (2) We show how some well-known social-psychological phenomena (e.g., self-serving biases) can be explained in terms of active interpersonal inference. (3) Mentalizing naturally entails Bayesian updating of how people value social outcomes. Crucially this includes inference about one's own qualities and preferences. Conclusion: We inaugurate a Bayes optimal framework for modeling intersubject variability in mentalizing during interpersonal exchanges. Here, interpersonal representations are endowed with explicit functional and affective properties. We suggest the active inference framework lends itself to the study of psychiatric conditions where mentalizing is distorted. PMID:24723872
10 CFR 963.14 - Preclosure suitability criteria.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 10 Energy 4 2012-01-01 2012-01-01 false Preclosure suitability criteria. 963.14 Section 963.14 Energy DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability Determination, Methods, and Criteria § 963.14 Preclosure suitability criteria. DOE will evaluate preclosure...
10 CFR 963.14 - Preclosure suitability criteria.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 10 Energy 4 2013-01-01 2013-01-01 false Preclosure suitability criteria. 963.14 Section 963.14 Energy DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability Determination, Methods, and Criteria § 963.14 Preclosure suitability criteria. DOE will evaluate preclosure...
10 CFR 963.14 - Preclosure suitability criteria.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 10 Energy 4 2014-01-01 2014-01-01 false Preclosure suitability criteria. 963.14 Section 963.14 Energy DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability Determination, Methods, and Criteria § 963.14 Preclosure suitability criteria. DOE will evaluate preclosure...
10 CFR 963.14 - Preclosure suitability criteria.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 10 Energy 4 2011-01-01 2011-01-01 false Preclosure suitability criteria. 963.14 Section 963.14 Energy DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability Determination, Methods, and Criteria § 963.14 Preclosure suitability criteria. DOE will evaluate preclosure...
10 CFR 963.14 - Preclosure suitability criteria.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 10 Energy 4 2010-01-01 2010-01-01 false Preclosure suitability criteria. 963.14 Section 963.14 Energy DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability Determination, Methods, and Criteria § 963.14 Preclosure suitability criteria. DOE will evaluate preclosure...
NASA Technical Reports Server (NTRS)
Jamsek, Damir A.
1993-01-01
A brief example of the use of formal methods techniques in the specification of a software system is presented. The report is part of a larger effort targeted at defining a formal methods pilot project for NASA. One possible application domain that may be used to demonstrate the effective use of formal methods techniques within the NASA environment is presented. It is not intended to provide a tutorial on either formal methods techniques or the application being addressed. It should, however, provide an indication that the application being considered is suitable for a formal methods by showing how such a task may be started. The particular system being addressed is the Structured File Services (SFS), which is a part of the Data Storage and Retrieval Subsystem (DSAR), which in turn is part of the Data Management System (DMS) onboard Spacestation Freedom. This is a software system that is currently under development for NASA. An informal mathematical development is presented. Section 3 contains the same development using Penelope (23), an Ada specification and verification system. The complete text of the English version Software Requirements Specification (SRS) is reproduced in Appendix A.
Environmental Education in the Formal Sector of Education in Uganda.
ERIC Educational Resources Information Center
Mucunguzi, P.
1995-01-01
Provides a critical review of the present state of environmental education in the formal sector of education in Uganda. Recommends an improved approach to formal environmental education based on a multidisciplinary foundation that embraces the biophysical environment, people, culture, politics, and socioeconomic systems. (LZ)
I, Pronoun: A Study of Formality in Online Content
ERIC Educational Resources Information Center
Thayer, Alexander; Evans, Mary B.; McBride, Alicia A.; Queen, Matt; Spyridakis, Jan H.
2010-01-01
This article presents the results of a study that investigated readers' perceptions of tone formality in online text passages. The study found that readers perceived text passages to be less formal when they contained personal pronouns, active voice verbs, informal punctuation, or verb contractions. The study reveals that professional…
Integrating Formal and Grounded Representations in Combinatorics Learning
ERIC Educational Resources Information Center
Braithwaite, David W.; Goldstone, Robert L.
2013-01-01
The terms "concreteness fading" and "progressive formalization" have been used to describe instructional approaches to science and mathematics that use grounded representations to introduce concepts and later transition to more formal representations of the same concepts. There are both theoretical and empirical reasons to…
47 CFR 8.14 - General formal complaint procedures.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 47 Telecommunication 1 2014-10-01 2014-10-01 false General formal complaint procedures. 8.14 Section 8.14 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRESERVING THE OPEN INTERNET § 8.14 General formal complaint procedures. (a) Complaints. In addition to the general...
47 CFR 8.14 - General formal complaint procedures.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 47 Telecommunication 1 2011-10-01 2011-10-01 false General formal complaint procedures. 8.14 Section 8.14 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRESERVING THE OPEN INTERNET § 8.14 General formal complaint procedures. (a) Complaints. In addition to the general...
47 CFR 8.14 - General formal complaint procedures.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 47 Telecommunication 1 2012-10-01 2012-10-01 false General formal complaint procedures. 8.14 Section 8.14 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRESERVING THE OPEN INTERNET § 8.14 General formal complaint procedures. (a) Complaints. In addition to the general...
47 CFR 8.14 - General formal complaint procedures.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 47 Telecommunication 1 2013-10-01 2013-10-01 false General formal complaint procedures. 8.14 Section 8.14 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRESERVING THE OPEN INTERNET § 8.14 General formal complaint procedures. (a) Complaints. In addition to the general...
Financing Adult and Non-Formal Education in Nigeria
ERIC Educational Resources Information Center
Hassan, Moshood Ayinde
2009-01-01
The purpose of this study is to determine how adult and non formal education is financed in Nigeria; and to examine areas or forms of and the problems of financing adult and non-formal education in Nigeria. Survey research was used in order to carry out the study. Three hundred and twenty five (325) respondents from government agencies,…
Toward the Characterization of Non-Formal Pedagogy.
ERIC Educational Resources Information Center
Silberman-Keller, Diana
This study examined characteristic attributes of non-formal education and the non-formal pedagogy directing its teaching and learning processes. Data were collected on organizational and pedagogical characteristics in several out-of-school organizations (youth movements, youth organizations, community centers, bypass educational systems, local…
Academic Achievement and Formal Thought in Engineering Students
ERIC Educational Resources Information Center
Vazquez, Stella Maris; de Anglat, Hilda Difabio
2009-01-01
Introduction: Research on university-level academic performance has significantly linked failure and dropping out to formal reasoning deficiency. We have not found any papers on formal thought in Argentine university students, in spite of the obvious shortcomings observed in the classrooms. Thus, the main objective of this paper was exploring the…
How Online Journalists Learn within a Non-Formal Context
ERIC Educational Resources Information Center
Kronstad, Morten; Eide, Martin
2015-01-01
Purpose: The purpose of this paper is to contribute to the understanding of workplace learning, with a focus on the non-formal learning that takes place among online journalists. The focus of this article is journalists working in an online newspaper and their experiences with workplace and non-formal learning, centering on framework conditions…
Beyond Formalism: Literary Criticism Now and in the Immediate Future.
ERIC Educational Resources Information Center
Standley, Fred L.
Formalism, an amalgamation of literary critical methods originating in the 1920's, which emphasize close textual analysis of the literary work itself, is declining as the predominant critical approach due to its self-imposed limitations. New perspectives, attempting to counter the fragmentation of formalism and demonstrating an awareness of the…
A Construction and Validation of Formal Operational Reasoning Instruments.
ERIC Educational Resources Information Center
Bart, William M.
In Piaget's developmental psychology the fourth and highest stage of human cognitive development is that of formal operations. The research on formal thought instruments is outlined. This study was designed to construct and validate paper-and-pencil instruments which could be used to select students capable of abstract conceptualization,…
The Archival Photograph and Its Meaning: Formalisms for Modeling Images
ERIC Educational Resources Information Center
Benson, Allen C.
2009-01-01
This article explores ontological principles and their potential applications in the formal description of archival photographs. Current archival descriptive practices are reviewed and the larger question is addressed: do archivists who are engaged in describing photographs need a more formalized system of representation, or do existing encoding…
Recognising Non-Formal and Informal Learning: An Open Challenge
ERIC Educational Resources Information Center
Perulli, Elisabetta
2009-01-01
The social-institutional endorsement towards the perspective of recognising and enhancing learning acquired outside the formal education and training contexts (non-formal and informal learning), has been gaining strength and has entered policy agendas throughout Europe, but also in other major non-European countries. Nevertheless there are still…
Pedagogical Basis of DAS Formalism in Engineering Education
ERIC Educational Resources Information Center
Hiltunen, J.; Heikkinen, E.-P.; Jaako, J.; Ahola, J.
2011-01-01
The paper presents a new approach for a bachelor-level curriculum structure in engineering. The approach is called DAS formalism according to its three phases: description, analysis and synthesis. Although developed specifically for process and environmental engineering, DAS formalism has a generic nature and it could also be used in other…
21 CFR 1404.835 - Are debarment proceedings formal?
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Are debarment proceedings formal? 1404.835 Section 1404.835 Food and Drugs OFFICE OF NATIONAL DRUG CONTROL POLICY GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Debarment § 1404.835 Are debarment proceedings formal? (a) Debarment proceedings are conducted...
21 CFR 1404.740 - Are suspension proceedings formal?
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Are suspension proceedings formal? 1404.740 Section 1404.740 Food and Drugs OFFICE OF NATIONAL DRUG CONTROL POLICY GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Suspension § 1404.740 Are suspension proceedings formal? (a)...
Formal Education, Eminence, and Dogmatism: The Curvilinear Relationship.
ERIC Educational Resources Information Center
Simonton, Dean Keith
The relationship between formal education and creativity was investigated in two studies. A reanalysis of Cox's (1926) 301 geniuses indicated that achieved eminence of creators is a curvilinear inverted-U function of formal education. Secondly, a study of 33 American presidents found that dogmatism (i.e., idealistic inflexibility) is a curvilinear…
Toward a mathematical formalism of performance, task difficulty, and activation
NASA Technical Reports Server (NTRS)
Samaras, George M.
1988-01-01
The rudiments of a mathematical formalism for handling operational, physiological, and psychological concepts are developed for use by the man-machine system design engineer. The formalism provides a framework for developing a structured, systematic approach to the interface design problem, using existing mathematical tools, and simplifying the problem of telling a machine how to measure and use performance.
13 CFR 301.10 - Formal application requirements.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Formal application requirements. 301.10 Section 301.10 Business Credit and Assistance ECONOMIC DEVELOPMENT ADMINISTRATION, DEPARTMENT... Projects selected from successful proposals, EDA will invite the proponents to submit a formal...
Blending Formal and Informal Learning Networks for Online Learning
ERIC Educational Resources Information Center
Czerkawski, Betül C.
2016-01-01
With the emergence of social software and the advance of web-based technologies, online learning networks provide invaluable opportunities for learning, whether formal or informal. Unlike top-down, instructor-centered, and carefully planned formal learning settings, informal learning networks offer more bottom-up, student-centered participatory…
Enhancing Formal E-Learning with Edutainment on Social Networks
ERIC Educational Resources Information Center
Labus, A.; Despotovic-Zrakic, M.; Radenkovic, B.; Bogdanovic, Z.; Radenkovic, M.
2015-01-01
This paper reports on the investigation of the possibilities of enhancing the formal e-learning process by harnessing the potential of informal game-based learning on social networks. The goal of the research is to improve the outcomes of the formal learning process through the design and implementation of an educational game on a social network…
On the Equivalence of Formal Grammars and Machines.
ERIC Educational Resources Information Center
Lund, Bruce
1991-01-01
Explores concepts of formal language and automata theory underlying computational linguistics. A computational formalism is described known as a "logic grammar," with which computational systems process linguistic data, with examples in declarative and procedural semantics and definite clause grammars. (13 references) (CB)
Adolescent Egocentrism and Formal Operations: Tests of a Theoretical Assumption.
ERIC Educational Resources Information Center
Lapsley, David K.; And Others
1986-01-01
Describes two studies of the theoretical relation between adolescent egocentrism and formal operations. Study 1 used the Adolescent Egocentrism Scale (AES) and Lunzer's battery of formal reasoning tasks to assess 183 adolescents. Study 2 administered the AES, the Imaginary Audience Scale (IAS), and the Test of Logical Thinking to 138 adolescents.…
Suitability of amphibians and reptiles for translocation.
Germano, Jennifer M; Bishop, Phillip J
2009-02-01
Translocations are important tools in the field of conservation. Despite increased use over the last few decades, the appropriateness of translocations for amphibians and reptiles has been debated widely over the past 20 years. To provide a comprehensive evaluation of the suitability of amphibians and reptiles for translocation, we reviewed the results of amphibian and reptile translocation projects published between 1991 and 2006. The success rate of amphibian and reptile translocations reported over this period was twice that reported in an earlier review in 1991. Success and failure rates were independent of the taxonomic class (Amphibia or Reptilia) released. Reptile translocations driven by human-wildlife conflict mitigation had a higher failure rate than those motivated by conservation, and more recent projects of reptile translocations had unknown outcomes. The outcomes of amphibian translocations were significantly related to the number of animals released, with projects releasing over 1000 individuals being most successful. The most common reported causes of translocation failure were homing and migration of introduced individuals out of release sites and poor habitat. The increased success of amphibian and reptile translocations reviewed in this study compared with the 1991 review is encouraging for future conservation projects. Nevertheless, more preparation, monitoring, reporting of results, and experimental testing of techniques and reintroduction questions need to occur to improve translocations of amphibians and reptiles as a whole.
On the formalization and reuse of scientific research.
King, Ross D; Liakata, Maria; Lu, Chuan; Oliver, Stephen G; Soldatova, Larisa N
2011-10-01
The reuse of scientific knowledge obtained from one investigation in another investigation is basic to the advance of science. Scientific investigations should therefore be recorded in ways that promote the reuse of the knowledge they generate. The use of logical formalisms to describe scientific knowledge has potential advantages in facilitating such reuse. Here, we propose a formal framework for using logical formalisms to promote reuse. We demonstrate the utility of this framework by using it in a worked example from biology: demonstrating cycles of investigation formalization [F] and reuse [R] to generate new knowledge. We first used logic to formally describe a Robot scientist investigation into yeast (Saccharomyces cerevisiae) functional genomics [f(1)]. With Robot scientists, unlike human scientists, the production of comprehensive metadata about their investigations is a natural by-product of the way they work. We then demonstrated how this formalism enabled the reuse of the research in investigating yeast phenotypes [r(1) = R(f(1))]. This investigation found that the removal of non-essential enzymes generally resulted in enhanced growth. The phenotype investigation was then formally described using the same logical formalism as the functional genomics investigation [f(2) = F(r(1))]. We then demonstrated how this formalism enabled the reuse of the phenotype investigation to investigate yeast systems-biology modelling [r(2) = R(f(2))]. This investigation found that yeast flux-balance analysis models fail to predict the observed changes in growth. Finally, the systems biology investigation was formalized for reuse in future investigations [f(3) = F(r(2))]. These cycles of reuse are a model for the general reuse of scientific knowledge. PMID:21490004
On the formalization and reuse of scientific research
King, Ross D.; Liakata, Maria; Lu, Chuan; Oliver, Stephen G.; Soldatova, Larisa N.
2011-01-01
The reuse of scientific knowledge obtained from one investigation in another investigation is basic to the advance of science. Scientific investigations should therefore be recorded in ways that promote the reuse of the knowledge they generate. The use of logical formalisms to describe scientific knowledge has potential advantages in facilitating such reuse. Here, we propose a formal framework for using logical formalisms to promote reuse. We demonstrate the utility of this framework by using it in a worked example from biology: demonstrating cycles of investigation formalization [F] and reuse [R] to generate new knowledge. We first used logic to formally describe a Robot scientist investigation into yeast (Saccharomyces cerevisiae) functional genomics [f1]. With Robot scientists, unlike human scientists, the production of comprehensive metadata about their investigations is a natural by-product of the way they work. We then demonstrated how this formalism enabled the reuse of the research in investigating yeast phenotypes [r1 = R(f1)]. This investigation found that the removal of non-essential enzymes generally resulted in enhanced growth. The phenotype investigation was then formally described using the same logical formalism as the functional genomics investigation [f2 = F(r1)]. We then demonstrated how this formalism enabled the reuse of the phenotype investigation to investigate yeast systems-biology modelling [r2 = R(f2)]. This investigation found that yeast flux-balance analysis models fail to predict the observed changes in growth. Finally, the systems biology investigation was formalized for reuse in future investigations [f3 = F(r2)]. These cycles of reuse are a model for the general reuse of scientific knowledge. PMID:21490004
Mixed symmetry tensors in the worldline formalism
NASA Astrophysics Data System (ADS)
Corradini, Olindo; Edwards, James P.
2016-05-01
We consider the first quantised approach to quantum field theory coupled to a non-Abelian gauge field. Representing the colour degrees of freedom with a single family of auxiliary variables the matter field transforms in a reducible representation of the gauge group which — by adding a suitable Chern-Simons term to the particle action — can be projected onto a chosen fully (anti-)symmetric representation. By considering F families of auxiliary variables, we describe how to extend the model to arbitrary tensor products of F reducible representations, which realises a U( F ) "flavour" symmetry on the world-line particle model. Gauging this symmetry allows the introduction of constraints on the Hilbert space of the colour fields which can be used to project onto an arbitrary irreducible representation, specified by a certain Young tableau. In particular the occupation numbers of the wavefunction — i.e. the lengths of the columns (rows) of the Young tableau — are fixed through the introduction of Chern-Simons terms. We verify this projection by calculating the number of colour degrees of freedom associated to the matter field. We suggest that, using the worldline approach to quantum field theory, this mechanism will allow the calculation of one-loop scattering amplitudes with the virtual particle in an arbitrary representation of the gauge group.
Predatory aquatic beetles, suitable trace elements bioindicators.
Burghelea, Carmen I; Zaharescu, Dragos G; Hooda, Peter S; Palanca-Soler, Antonio
2011-05-01
Predatory aquatic beetles are common colonizers of natural and managed aquatic environments. While as important components of the aquatic food webs they are prone to accumulate trace elements, they have been largely neglected from metal uptake studies. We aim to test the suitability of three dytiscid species, i.e.Hydroglyphus pusillus, Laccophilus minutus and Rhantus suturalis, as trace elements (Al, As, Cd, Co, Cu, Fe, Mn, Mo, Ni, Pb, Se and Zn) bioindicators. The work was carried out in a case area representing rice paddies and control sites (reservoirs) from an arid region known for its land degradation (Monegros, NE Spain). Categorical principal component analysis (CATPCA) was tested as a nonlinear approach to identify significant relationships between metals, species and habitat conditions so as to examine the ability of these species to reflect differences in metal uptake. Except Se and As, the average concentrations of all other elements in the beetles were higher in the rice fields than in the control habitats. The CATPCA determined that H. pusillus had high capacity to accumulate Fe, Ni and Mn regardless of the habitat type, and hence may not be capable of distinguishing habitat conditions with regards to these metals. On the other hand, L. minutus was found less sensitive for Se in non-managed habitats (i.e. reservoirs), while R. suturalis was good in accumulating Al, Mo and Pb in rice fields. The latter seems to be a promising bioindicator of metal enrichment in rice fields. We conclude that predatory aquatic beetles are good candidates for trace elements bioindication in impacted and non-impacted environments and can be used in environmental monitoring studies. CATPCA proved to be a reliable approach to unveil trends in metal accumulation in aquatic invertebrates according to their habitat status.
ERIC Educational Resources Information Center
Zamora, Julieta Lopez; Reynaga, Francisco Javier Arriaga
2010-01-01
This paper presents results of two research works, the first approaches non-formal education and the second addresses formal education. In both studies in-depth interview techniques were used. There were some points of convergence between them on aspects such as the implementation of learning environments and the integration of ICT. The interview…
ERIC Educational Resources Information Center
Eaton, Sarah Elaine
2010-01-01
This research report investigates the links between formal, non-formal and informal learning and the differences between them. In particular, the report aims to link these notions of learning to literacy and essential skills, as well as the learning of second and other languages in Canada. It builds upon the work of the OECD (n.d.) and Werquin…
Habitat Suitability Index Models and Instream Flow Suitability Curves: Spotted bass
McMahon, Thomas E.; Gebhart, Glen; Maughan, O. Eugene; Nelson, Patrick C.
1984-01-01
The Habitat Suitability Index (HSI) models presented in this publication aid in identifying habitat variable important to the growth and survival of spotted bass (Micropterus punctulatus). Facts, ideas, and concepts obtained from the research literature and expert reviews are synthesized and presented in a format that can be used for impact assessment. The models are hypotheses of species-habitat relationships, and model users should recognize that the degree of veracity of the HSI model, SI graphs, and assumptions will vary according to geographical area and the extent of the data base for individual variables. A brief discussion of selected Suitability Index (SI) curves as used in the Instream Flow Incremental Methodology (IFIM), and a discussion of SI curves available for the IFIM analysis of Spotted bass habitat are also included.
Correlates of formal reasoning: Content and problem effects
NASA Astrophysics Data System (ADS)
Linn, Marcia C.; Pulos, Steven; Gans, Adrienne
Piaget's structural theory of formal thought suggests that a general construct of formal reasoning exists. The content of the task and type of problem employed are often ignored in Piagetian based studies but are important for generalizing findings to other studies and to educational problems. The study reported here examines content and problem effects of formal thought in 13-year-old adolescents. Specifically, three controlling variables tasks with different content and two question type tests (analysis and controlling questions) were administered to 120 seventh graders. Ability measures and personality dimensions associated with formal reasoning in the literature are used to clarify what formal reasoning is and how content and problem type are involved in formal reasoning. Significant main effects were found for problem and content effects (p = 0.001), and a significant interaction was found between the two (p = 0.001). Across the three tasks general ability, field dependency, and locus of control were consistently and significantly related to the controlling questions. However, only measures of field dependency were related to the analysis questions. Combinations of ability and personality factors were found to be uniquely related to each task, within each question type. Results have implications for a theory of formal thought and the teaching of the controlling variables strategy.
What do tests of formal reasoning actually measure?
NASA Astrophysics Data System (ADS)
Lawson, Anton E.
Tests of formal operational reasoning derived from Piagetian theory have been found to be effective predictors of academic achievement. Yet Piaget's theory regarding the underlying nature of formal operations and their employment in specific contexts has run into considerable empirical difficulty. The primary purpose of this study was to present the core of an alternative theory of the nature of advanced scientific reasoning. That theory, referred to as the multiple-hypothesis theory, argues that tests of formal operational reasoning actually measure the extent to which persons have acquired the ability to initiate reasoning with more than one specific antecedent condition, or if they are unable to imagine more than one antecedent condition, they are aware that more than one is possible; therefore conclusions that are drawn are tempered by this possibility. As a test of this multiple-hypothesis theory of advanced reasoning and the contrasting Piagetian theory of formal operations, a sample of 922 college students were first classified as concrete operational, transitional, or formal operational, based upon responses to standard Piagetian measures of formal operational reasoning. They were then administered seven logic tasks. Actual response patterns to the tasks were analyzed and found to be similar to predicted response patterns derived from the multiple-hypothesis theory and were different from those predicted by Piagetian theory. Therefore, support was obtained for the multiple-hypothesis theory. The terms intuitive and reflective were suggested to replace the terms concrete operational and formal operational to refer to persons at varying levels of intellectual development.
A review of research on formal reasoning and science teaching
NASA Astrophysics Data System (ADS)
Lawson, Anton E.
A central purpose of education is to improve students' reasoning abilities. The present review examines research in developmental psychology and science education that has attempted to assess the validity of Piaget's theory of formal thought and its relation to educational practice. Should a central objective of schools be to help students become formal thinkers? To answer this question research has focused on the following subordinate questions: (1) What role does biological maturation play in the development of formal reasoning? (2) Are Piaget's formal tasks reliable and valid? (3) Does formal reasoning constitute a unified and general mode of intellectual functioning? (4) How does the presence or absence of formal reasoning affect school achievement? (5) Can formal reasoning be taught? (6) What is the structural or functional nature of advanced reasoning? The general conclusion drawn is that although Piaget's work and that which has sprung from it leaves a number of unresolved theoretical and methodological problems, it provides an important background from which to make substantial progress toward a most significant educational objective.All our dignity lies in thought. By thought we must elevate ourselves, not by space and time which we can not fill. Let us endeavor then to think well; therein lies the principle of morality. Blaise Pascal 1623-1662.
Automatic derivation of formal software specifications from informal descriptions
NASA Technical Reports Server (NTRS)
Miriyala, Kanth; Harandi, Mehdi T.
1991-01-01
SPECIFIER, an interactive system which derives formal specifications of data types and programs from their informal descriptions, is described. The process of deriving formal specifications is viewed as a problem-solving process. The system uses common problem-solving techniques such as schemas, analogy, and difference-based reasoning to derive formal specifications. If an informal description is a commonly occurring operation for which the system has a schema, then the formal specification is derived by instantiating the schema. If there is no such schema, SPECIFIER tries to find a previously solved problem which is analogous to the current problem. If the problem found is directly analogous to the current problem, it applies an analogy mapping to obtain a formal specification. On the other hand, if the analogy found is only approximate, it solves the directly analogous part of the problem by analogy and performs difference-based reasoning using the remaining (unmatched) parts to transform the formal specification obtained by analogy to a formal specification for the entire original problem.
Proceedings of the Second NASA Formal Methods Symposium
NASA Technical Reports Server (NTRS)
Munoz, Cesar (Editor)
2010-01-01
This publication contains the proceedings of the Second NASA Formal Methods Symposium sponsored by the National Aeronautics and Space Administration and held in Washington D.C. April 13-15, 2010. Topics covered include: Decision Engines for Software Analysis using Satisfiability Modulo Theories Solvers; Verification and Validation of Flight-Critical Systems; Formal Methods at Intel -- An Overview; Automatic Review of Abstract State Machines by Meta Property Verification; Hardware-independent Proofs of Numerical Programs; Slice-based Formal Specification Measures -- Mapping Coupling and Cohesion Measures to Formal Z; How Formal Methods Impels Discovery: A Short History of an Air Traffic Management Project; A Machine-Checked Proof of A State-Space Construction Algorithm; Automated Assume-Guarantee Reasoning for Omega-Regular Systems and Specifications; Modeling Regular Replacement for String Constraint Solving; Using Integer Clocks to Verify the Timing-Sync Sensor Network Protocol; Can Regulatory Bodies Expect Efficient Help from Formal Methods?; Synthesis of Greedy Algorithms Using Dominance Relations; A New Method for Incremental Testing of Finite State Machines; Verification of Faulty Message Passing Systems with Continuous State Space in PVS; Phase Two Feasibility Study for Software Safety Requirements Analysis Using Model Checking; A Prototype Embedding of Bluespec System Verilog in the PVS Theorem Prover; SimCheck: An Expressive Type System for Simulink; Coverage Metrics for Requirements-Based Testing: Evaluation of Effectiveness; Software Model Checking of ARINC-653 Flight Code with MCP; Evaluation of a Guideline by Formal Modelling of Cruise Control System in Event-B; Formal Verification of Large Software Systems; Symbolic Computation of Strongly Connected Components Using Saturation; Towards the Formal Verification of a Distributed Real-Time Automotive System; Slicing AADL Specifications for Model Checking; Model Checking with Edge-valued Decision Diagrams
Formal Specification of the OpenMP Memory Model
Bronevetsky, G; de Supinski, B
2006-12-19
OpenMP [2] is an important API for shared memory programming, combining shared memory's potential for performance with a simple programming interface. Unfortunately, OpenMP lacks a critical tool for demonstrating whether programs are correct: a formal memory model. Instead, the current official definition of the OpenMP memory model (the OpenMP 2.5 specification [2]) is in terms of informal prose. As a result, it is impossible to verify OpenMP applications formally since the prose does not provide a formal consistency model that precisely describes how reads and writes on different threads interact. We expand on our previous work that focused on the formal verification of OpenMP programs through a formal memory model [?]. As in that work, our formalization, which is derived from the existing prose model [2], provides a two-step process to verify whether an observed OpenMP execution is conformant. This paper extends the model to cover the entire specification. In addition to this formalization, our contributions include a discussion of ambiguities in the current prose-based memory model description. Although our formal model may not capture the current informal memory model perfectly, in part due to these ambiguities, our model reflects our understanding of the informal model's intent. We conclude with several examples that may indicate areas of the OpenMP memory model that need further refinement, however it is specified. Our goal is to motivate the OpenMP community to adopt those refinements eventually, ideally through a formal model, in later OpenMP specifications.
[Climate suitability for tea growing in Zhejiang Province].
Jin, Zhi-Feng; Ye, Jian-Gang; Yang, Zai-Qiang; Sun, Rui; Hu, Bo; Li, Ren-Zhong
2014-04-01
It is important to quantitatively assess the climate suitability of tea and its response to climate change. Based on meteorological indices of tea growth and daily meteorological data from 1971 to 2010 in Zhejiang Province, three climate suitability models for single climate factors, including temperature, precipitation and sunshine, were established at a 10-day scale by using the fuzzy mathematics method, and a comprehensive climate suitability model was established with the geometric average method. The results indicated that the climate suitability was high in the tea growth season in Zhejiang Province, and the three kinds of climate suitability were all higher than 0.6. As for the single factor climate suitability, temperature suitability was the highest and sunshine suitability was the lowest. There were obvious inter-annual variations of tea climate suitability, with a decline trend in the 1970s, less variation in the 1980s, and an obvious incline trend after the 1990s. The change tendency of climate suitability for spring tea was similar with that of annual climate suitability, lower in the 1980s, higher in the 1970s and after the 1990s. However, the variation amplitude of the climate suitability for spring tea was larger. The climate suitability for summer tea and autumn tea showed a decline trend from 1971 to 2010.
Multisymplectic Lagrangian and Hamiltonian Formalisms of Classical Field Theories
NASA Astrophysics Data System (ADS)
Román-Roy, Narciso
2009-11-01
This review paper is devoted to presenting the standard multisymplectic formulation for describing geometrically classical field theories, both the regular and singular cases. First, the main features of the Lagrangian formalism are revisited and, second, the Hamiltonian formalism is constructed using Hamiltonian sections. In both cases, the variational principles leading to the Euler-Lagrange and the Hamilton-De Donder-Weyl equations, respectively, are stated, and these field equations are given in different but equivalent geometrical ways in each formalism. Finally, both are unified in a new formulation (which has been developed in the last years), following the original ideas of Rusk and Skinner for mechanical systems.
A Novel Concept Acquisition Approach Based on Formal Contexts
Qian, Ting; Wei, Ling
2014-01-01
As an important tool for data analysis and knowledge processing, formal concept analysis (FCA) has been applied to many fields. In this paper, we introduce a new method to find all formal concepts based on formal contexts. The amount of intents calculation is reduced by the method. And the corresponding algorithm of our approach is proposed. The main theorems and the corresponding algorithm are examined by examples, respectively. At last, several real-life databases are analyzed to demonstrate the application of the proposed approach. Experimental results show that the proposed approach is simple and effective. PMID:25147834
10 CFR 963.16 - Postclosure suitability evaluation method.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 10 Energy 4 2012-01-01 2012-01-01 false Postclosure suitability evaluation method. 963.16 Section... Determination, Methods, and Criteria § 963.16 Postclosure suitability evaluation method. (a) DOE will evaluate postclosure suitability using the total system performance assessment method. DOE will conduct a total...
10 CFR 963.16 - Postclosure suitability evaluation method.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 10 Energy 4 2013-01-01 2013-01-01 false Postclosure suitability evaluation method. 963.16 Section... Determination, Methods, and Criteria § 963.16 Postclosure suitability evaluation method. (a) DOE will evaluate postclosure suitability using the total system performance assessment method. DOE will conduct a total...
10 CFR 963.16 - Postclosure suitability evaluation method.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 10 Energy 4 2011-01-01 2011-01-01 false Postclosure suitability evaluation method. 963.16 Section... Determination, Methods, and Criteria § 963.16 Postclosure suitability evaluation method. (a) DOE will evaluate postclosure suitability using the total system performance assessment method. DOE will conduct a total...
10 CFR 963.16 - Postclosure suitability evaluation method.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 10 Energy 4 2014-01-01 2014-01-01 false Postclosure suitability evaluation method. 963.16 Section... Determination, Methods, and Criteria § 963.16 Postclosure suitability evaluation method. (a) DOE will evaluate postclosure suitability using the total system performance assessment method. DOE will conduct a total...
10 CFR 963.12 - Preclosure suitability determination.
Code of Federal Regulations, 2010 CFR
2010-01-01
....12 Energy DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability... and criteria described in §§ 963.13 and 963.14 to evaluate the suitability of the Yucca Mountain site... under § 963.13 show that the Yucca Mountain site is likely to meet the applicable radiation...
10 CFR 963.15 - Postclosure suitability determination.
Code of Federal Regulations, 2011 CFR
2011-01-01
....15 Energy DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability... and criteria described in §§ 963.16 and 963.17 to evaluate the suitability of the Yucca Mountain site... conducted under § 963.16 show that the Yucca Mountain site is likely to meet the applicable...
10 CFR 963.15 - Postclosure suitability determination.
Code of Federal Regulations, 2014 CFR
2014-01-01
....15 Energy DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability... and criteria described in §§ 963.16 and 963.17 to evaluate the suitability of the Yucca Mountain site... conducted under § 963.16 show that the Yucca Mountain site is likely to meet the applicable...
10 CFR 963.15 - Postclosure suitability determination.
Code of Federal Regulations, 2012 CFR
2012-01-01
....15 Energy DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability... and criteria described in §§ 963.16 and 963.17 to evaluate the suitability of the Yucca Mountain site... conducted under § 963.16 show that the Yucca Mountain site is likely to meet the applicable...
10 CFR 963.12 - Preclosure suitability determination.
Code of Federal Regulations, 2011 CFR
2011-01-01
....12 Energy DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability... and criteria described in §§ 963.13 and 963.14 to evaluate the suitability of the Yucca Mountain site... under § 963.13 show that the Yucca Mountain site is likely to meet the applicable radiation...
10 CFR 963.12 - Preclosure suitability determination.
Code of Federal Regulations, 2012 CFR
2012-01-01
....12 Energy DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability... and criteria described in §§ 963.13 and 963.14 to evaluate the suitability of the Yucca Mountain site... under § 963.13 show that the Yucca Mountain site is likely to meet the applicable radiation...
10 CFR 963.13 - Preclosure suitability evaluation method.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 10 Energy 4 2013-01-01 2013-01-01 false Preclosure suitability evaluation method. 963.13 Section 963.13 Energy DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability... geologic repository at the Yucca Mountain site using the method described in paragraph (b) of this...
10 CFR 963.13 - Preclosure suitability evaluation method.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 10 Energy 4 2010-01-01 2010-01-01 false Preclosure suitability evaluation method. 963.13 Section 963.13 Energy DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability... geologic repository at the Yucca Mountain site using the method described in paragraph (b) of this...
10 CFR 963.13 - Preclosure suitability evaluation method.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 10 Energy 4 2011-01-01 2011-01-01 false Preclosure suitability evaluation method. 963.13 Section 963.13 Energy DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability... geologic repository at the Yucca Mountain site using the method described in paragraph (b) of this...
10 CFR 963.15 - Postclosure suitability determination.
Code of Federal Regulations, 2010 CFR
2010-01-01
....15 Energy DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability... and criteria described in §§ 963.16 and 963.17 to evaluate the suitability of the Yucca Mountain site... conducted under § 963.16 show that the Yucca Mountain site is likely to meet the applicable...
10 CFR 963.12 - Preclosure suitability determination.
Code of Federal Regulations, 2013 CFR
2013-01-01
....12 Energy DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability... and criteria described in §§ 963.13 and 963.14 to evaluate the suitability of the Yucca Mountain site... under § 963.13 show that the Yucca Mountain site is likely to meet the applicable radiation...
10 CFR 963.15 - Postclosure suitability determination.
Code of Federal Regulations, 2013 CFR
2013-01-01
....15 Energy DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability... and criteria described in §§ 963.16 and 963.17 to evaluate the suitability of the Yucca Mountain site... conducted under § 963.16 show that the Yucca Mountain site is likely to meet the applicable...
10 CFR 963.13 - Preclosure suitability evaluation method.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 10 Energy 4 2014-01-01 2014-01-01 false Preclosure suitability evaluation method. 963.13 Section 963.13 Energy DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability... geologic repository at the Yucca Mountain site using the method described in paragraph (b) of this...
10 CFR 963.12 - Preclosure suitability determination.
Code of Federal Regulations, 2014 CFR
2014-01-01
....12 Energy DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability... and criteria described in §§ 963.13 and 963.14 to evaluate the suitability of the Yucca Mountain site... under § 963.13 show that the Yucca Mountain site is likely to meet the applicable radiation...
10 CFR 963.13 - Preclosure suitability evaluation method.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 10 Energy 4 2012-01-01 2012-01-01 false Preclosure suitability evaluation method. 963.13 Section 963.13 Energy DEPARTMENT OF ENERGY YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES Site Suitability... geologic repository at the Yucca Mountain site using the method described in paragraph (b) of this...
5 CFR 731.105 - Authority to take suitability actions.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 5 Administrative Personnel 2 2013-01-01 2013-01-01 false Authority to take suitability actions. 731.105 Section 731.105 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) SUITABILITY Scope § 731.105 Authority to take suitability actions....
5 CFR 731.105 - Authority to take suitability actions.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false Authority to take suitability actions. 731.105 Section 731.105 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) SUITABILITY Scope § 731.105 Authority to take suitability actions....
5 CFR 731.105 - Authority to take suitability actions.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 5 Administrative Personnel 2 2012-01-01 2012-01-01 false Authority to take suitability actions. 731.105 Section 731.105 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) SUITABILITY Scope § 731.105 Authority to take suitability actions....
5 CFR 731.105 - Authority to take suitability actions.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Authority to take suitability actions. 731.105 Section 731.105 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) SUITABILITY Scope § 731.105 Authority to take suitability actions....
Symmetric Space σ-MODEL Dynamics:. Current Formalism
NASA Astrophysics Data System (ADS)
Yilmaz, Nejat T.
After explicitly constructing the symmetric space sigma model Lagrangian in terms of the coset scalars of the solvable Lie algebra gauge in the current formalism, we derive the field equations of the theory.
Uncovering the triple omeron vertex from Wilson line formalism
Chirilli, G. A.; Szymanowski, L.; Wallon, S.
2011-01-01
We compute the triple omeron vertex from the Wilson line formalism, including both planar and nonplanar contributions, and get perfect agreement with the result obtained in the Extended Generalized Logarithmic Approximation based on Reggeon calculus.
Formal Organizational Structure and Participation in Planning Continuing Professional Education.
ERIC Educational Resources Information Center
Fox, Robert D.
1981-01-01
This study explored and described the relationship between formal organizational structures and the extent of participation of clients, faculty, and program administrators in planning continuing professional education programs in six Southern land-grant universities. (Author/CT)
CSR-induced emittance growth in achromats: Linear formalism revisited
NASA Astrophysics Data System (ADS)
Venturini, M.
2015-09-01
We review the R-matrix formalism used to describe Coherent Synchrotron Radiation (CSR)-induced projected emittance growth in electron beam transport lines and establish the connection with a description in terms of the dispersion-invariant function.
Formal methods and digital systems validation for airborne systems
NASA Technical Reports Server (NTRS)
Rushby, John
1993-01-01
This report has been prepared to supplement a forthcoming chapter on formal methods in the FAA Digital Systems Validation Handbook. Its purpose is as follows: to outline the technical basis for formal methods in computer science; to explain the use of formal methods in the specification and verification of software and hardware requirements, designs, and implementations; to identify the benefits, weaknesses, and difficulties in applying these methods to digital systems used on board aircraft; and to suggest factors for consideration when formal methods are offered in support of certification. These latter factors assume the context for software development and assurance described in RTCA document DO-178B, 'Software Considerations in Airborne Systems and Equipment Certification,' Dec. 1992.
A logarithmic correction in the entropy functional formalism
NASA Astrophysics Data System (ADS)
Hammad, Fayçal; Faizal, Mir
2016-04-01
The entropy functional formalism allows one to recover general relativity, modified gravity theories, as well as the Bekenstein-Hawking entropy formula. In most approaches to quantum gravity, the Bekenstein-Hawking’s entropy formula acquires a logarithmic correction term. As such terms occur almost universally in most approaches to quantum gravity, we analyze the effect of such terms on the entropy functional formalism. We demonstrate that the leading correction to the micro-canonical entropy in the entropy functional formalism can be used to recover modified theories of gravity already obtained with an uncorrected micro-canonical entropy. Furthermore, since the entropy functional formalism reproduces modified gravity, the rise of gravity-dependent logarithmic corrections turns out to be one way to impose constraints on these theories of modified gravity. The constraints found here for the simple case of an ℱ(R)-gravity are the same as those obtained in the literature from cosmological considerations.
Dominant partition method. [based on a wave function formalism
NASA Technical Reports Server (NTRS)
Dixon, R. M.; Redish, E. F.
1979-01-01
By use of the L'Huillier, Redish, and Tandy (LRT) wave function formalism, a partially connected method, the dominant partition method (DPM) is developed for obtaining few body reductions of the many body problem in the LRT and Bencze, Redish, and Sloan (BRS) formalisms. The DPM maps the many body problem to a fewer body one by using the criterion that the truncated formalism must be such that consistency with the full Schroedinger equation is preserved. The DPM is based on a class of new forms for the irreducible cluster potential, which is introduced in the LRT formalism. Connectivity is maintained with respect to all partitions containing a given partition, which is referred to as the dominant partition. Degrees of freedom corresponding to the breakup of one or more of the clusters of the dominant partition are treated in a disconnected manner. This approach for simplifying the complicated BRS equations is appropriate for physical problems where a few body reaction mechanism prevails.
Experiences Using Lightweight Formal Methods for Requirements Modeling
NASA Technical Reports Server (NTRS)
Easterbrook, Steve; Lutz, Robyn; Covington, Rick; Kelly, John; Ampo, Yoko; Hamilton, David
1997-01-01
This paper describes three case studies in the lightweight application of formal methods to requirements modeling for spacecraft fault protection systems. The case studies differ from previously reported applications of formal methods in that formal methods were applied very early in the requirements engineering process, to validate the evolving requirements. The results were fed back into the projects, to improve the informal specifications. For each case study, we describe what methods were applied, how they were applied, how much effort was involved, and what the findings were. In all three cases, formal methods enhanced the existing verification and validation processes, by testing key properties of the evolving requirements, and helping to identify weaknesses. We conclude that the benefits gained from early modeling of unstable requirements more than outweigh the effort needed to maintain multiple representations.
Understanding visualization: a formal approach using category theory and semiotics.
Vickers, Paul; Faith, Joe; Rossiter, Nick
2013-06-01
This paper combines the vocabulary of semiotics and category theory to provide a formal analysis of visualization. It shows how familiar processes of visualization fit the semiotic frameworks of both Saussure and Peirce, and extends these structures using the tools of category theory to provide a general framework for understanding visualization in practice, including: Relationships between systems, data collected from those systems, renderings of those data in the form of representations, the reading of those representations to create visualizations, and the use of those visualizations to create knowledge and understanding of the system under inspection. The resulting framework is validated by demonstrating how familiar information visualization concepts (such as literalness, sensitivity, redundancy, ambiguity, generalizability, and chart junk) arise naturally from it and can be defined formally and precisely. This paper generalizes previous work on the formal characterization of visualization by, inter alia, Ziemkiewicz and Kosara and allows us to formally distinguish properties of the visualization process that previous work does not.
NASA Technical Reports Server (NTRS)
Weber, Doug; Jamsek, Damir
1994-01-01
The goal of this task was to investigate how formal methods could be incorporated into a software engineering process for flight-control systems under DO-178B and to demonstrate that process by developing a formal specification for NASA's Guidance and Controls Software (GCS) Experiment. GCS is software to control the descent of a spacecraft onto a planet's surface. The GCS example is simplified from a real example spacecraft, but exhibits the characteristics of realistic spacecraft control software. The formal specification is written in Larch.
Skinner-Rusk unified formalism for higher-order systems
NASA Astrophysics Data System (ADS)
Prieto-Martínez, Pedro Daniel; Román-Roy, Narciso
2012-07-01
The Lagrangian-Hamiltonian unified formalism of R. Skinner and R. Rusk was originally stated for autonomous dynamical systems in classical mechanics. It has been generalized for non-autonomous first-order mechanical systems, first-order and higher-order field theories, and higher-order autonomous systems. In this work we present a generalization of this formalism for higher-order non-autonomous mechanical systems.
Formal functional test designs with a test representation language
NASA Technical Reports Server (NTRS)
Hops, J. M.
1993-01-01
The application of the category-partition method to the test design phase of hardware, software, or system test development is discussed. The method provides a formal framework for reducing the total number of possible test cases to a minimum logical subset for effective testing. An automatic tool and a formal language were developed to implement the method and produce the specification of test cases.
Adolescent thinking ála Piaget: The formal stage.
Dulit, E
1972-12-01
Two of the formal-stage experiments of Piaget and Inhelder, selected largely for their closeness to the concepts defining the stage, were replicated with groups of average and gifted adolescents. This report describes the relevant Piagetian concepts (formal stage, concrete stage) in context, gives the methods and findings of this study, and concludes with a section discussing implications and making some reformulations which generally support but significantly qualify some of the central themes of the Piaget-Inhelder work. Fully developed formal-stage thinking emerges as far from commonplace among normal or average adolescents (by marked contrast with the impression created by the Piaget-Inhelder text, which chooses to report no middle or older adolescents who function at less than fully formal levels). In this respect, the formal stage differs appreciably from the earlier Piagetian stages, and early adolescence emerges as the age for which a "single path" model of cognitive development becomes seriously inadequate and a more complex model becomes essential. Formal-stage thinking seems best conceptualized, like most other aspects of psychological maturity, as a potentiality only partially attained by most and fully attained only by some.
Proceedings of the First NASA Formal Methods Symposium
NASA Technical Reports Server (NTRS)
Denney, Ewen (Editor); Giannakopoulou, Dimitra (Editor); Pasareanu, Corina S. (Editor)
2009-01-01
Topics covered include: Model Checking - My 27-Year Quest to Overcome the State Explosion Problem; Applying Formal Methods to NASA Projects: Transition from Research to Practice; TLA+: Whence, Wherefore, and Whither; Formal Methods Applications in Air Transportation; Theorem Proving in Intel Hardware Design; Building a Formal Model of a Human-Interactive System: Insights into the Integration of Formal Methods and Human Factors Engineering; Model Checking for Autonomic Systems Specified with ASSL; A Game-Theoretic Approach to Branching Time Abstract-Check-Refine Process; Software Model Checking Without Source Code; Generalized Abstract Symbolic Summaries; A Comparative Study of Randomized Constraint Solvers for Random-Symbolic Testing; Component-Oriented Behavior Extraction for Autonomic System Design; Automated Verification of Design Patterns with LePUS3; A Module Language for Typing by Contracts; From Goal-Oriented Requirements to Event-B Specifications; Introduction of Virtualization Technology to Multi-Process Model Checking; Comparing Techniques for Certified Static Analysis; Towards a Framework for Generating Tests to Satisfy Complex Code Coverage in Java Pathfinder; jFuzz: A Concolic Whitebox Fuzzer for Java; Machine-Checkable Timed CSP; Stochastic Formal Correctness of Numerical Algorithms; Deductive Verification of Cryptographic Software; Coloured Petri Net Refinement Specification and Correctness Proof with Coq; Modeling Guidelines for Code Generation in the Railway Signaling Context; Tactical Synthesis Of Efficient Global Search Algorithms; Towards Co-Engineering Communicating Autonomous Cyber-Physical Systems; and Formal Methods for Automated Diagnosis of Autosub 6000.
Agronomic Suitability of Bioenergy Crops in Mississippi
Lemus, Rocky; Baldwin, Brian; Lang, David
2011-10-01
In Mississippi, some questions need to be answered about bioenergy crops: how much suitable land is available? How much material can that land produce? Which production systems work best in which scenarios? What levels of inputs will be required for productivity and longterm sustainability? How will the crops reach the market? What kinds of infrastructure will be necessary to make that happen? This publication helps answer these questions: ÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂ¢ÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂ¢ Which areas in the state are best for bioenergy crop production? ÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂ¢ÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂ¢ How much could these areas produce sustainably? ÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂ¢ÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂ¢ How can bioenergy crops impact carbon sequestration and carbon credits? ÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂ¢ÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂ
NASA Astrophysics Data System (ADS)
Brainis, E.; Emplit, Ph.
2010-06-01
Few-photon systems are best described by their wave function rather than by the usual quantum field formalism. In this work, we develop a photon wave function (PWF) formalism suitable for analyzing a wide variety of quantum optical problems related to propagation, diffraction and imaging with quantum states of light. We establish a generalized Huygens-Fresnel (GH-F) principle that describes the propagation of any paraxial N-photon state. This tool is very helpful for predicting photo-detection correlations in space and time due to an initial N-particle entanglement, even in complex situation. The effect of lenses, beam splitters, filters ... on the photon paths can be easily taken into account. We apply the PWF formalism and the GH-F principle to three specific problems in quantum optics. First, we revisit the Hong-Ou-Mandel two-photon interference effect and analyze the effect of photon shape mismatch in space, time and polarization using the PWF formalism. Second, we show how to use the GH-F principle to analyze "ghost" imaging and diffraction experiments with entangled photon pairs such as those realized by Strekalov et al. [Phys. Rev. Lett. 74, 3600 (1995)] and Pittman et al. [Phys. Rev. A 52, R3429 (1995)] in the nineties. Finally, we use the GH-F principle to analyze the resolution enhancement in a recent quantum imaging proposal based on N incoherent single-photon sources [Phys. Rev. Lett. 99, 133603 (2007) and Phys. Rev. A 80, 013820 (2009)].
Correlates of formal operational reasoning: A neo-piagetian analysis
NASA Astrophysics Data System (ADS)
Niaz, Mansoor
Most Piagetian formal operational reasoning tasks show horizontal decalage; that is, subjects pass certain tasks and fail others that have the same logical structure. The study reported here analyzes the importance of individual difference variables, as postulated by the neo-Piagetian theory of Pascual-Leone, in explaining subject performance in formal reasoning. A sample of 72 freshman students were administered a test of formal reasoning having 20 items of different types of reasoning, and the tests of the individual difference variables. Results obtained from multiple regression analyses show that Pascual-Leone's structural M-capacity (Ms) is the most consistent predictor of success in the different formal reasoning tasks, followed by Witkin's cognitive style, and to a much lesser degree Raven's progressive matrices, and Pascual-Leone's functional M-capacity (Mf). It was found that in the total score on the 20 items of formal reasoning, Ms accounted for 23.3% of the variance (R = 0.483, F = 6.39, p = 0.014) and Witkin's Group Embedded Figures Test, increased the multiple R significantly (F = 7.77, p = 0.007) and accounted for 7.6% of the variance. Mf and the Raven test did not make a significant contribution to the regression equation. Correlation coefficients among most of the items having the same reasoning pattern but different content are generally low but statistically significant (p < 0.01). Intercorrelations among items having the same formal reasoning pattern and content are fairly high (p < 0.001). These results emphasize the importance of individual difference variables: information-processing capacity (Pascual-Leone) and oversensitivity to potentially misleading information (Witkin). It is suggested that in order to understand student performance in formal reasoning tasks, we should expect horizontal decalages as a rule and not the exception, as Piaget had postulated. Educational implications are drawn.
Weaving a Formal Methods Education with Problem-Based Learning
NASA Astrophysics Data System (ADS)
Gibson, J. Paul
The idea of weaving formal methods through computing (or software engineering) degrees is not a new one. However, there has been little success in developing and implementing such a curriculum. Formal methods continue to be taught as stand-alone modules and students, in general, fail to see how fundamental these methods are to the engineering of software. A major problem is one of motivation — how can the students be expected to enthusiastically embrace a challenging subject when the learning benefits, beyond passing an exam and achieving curriculum credits, are not clear? Problem-based learning has gradually moved from being an innovative pedagogique technique, commonly used to better-motivate students, to being widely adopted in the teaching of many different disciplines, including computer science and software engineering. Our experience shows that a good problem can be re-used throughout a student's academic life. In fact, the best computing problems can be used with children (young and old), undergraduates and postgraduates. In this paper we present a process for weaving formal methods through a University curriculum that is founded on the application of problem-based learning and a library of good software engineering problems, where students learn about formal methods without sitting a traditional formal methods module. The process of constructing good problems and integrating them into the curriculum is shown to be analagous to the process of engineering software. This approach is not intended to replace more traditional formal methods modules: it will better prepare students for such specialised modules and ensure that all students have an understanding and appreciation for formal methods even if they do not go on to specialise in them.
Land-use suitability analysis for urban development in Beijing.
Liu, Renzhi; Zhang, Ke; Zhang, Zhijiao; Borthwick, Alistair G L
2014-12-01
Land-use suitability analyses are of considerable use in the planning of mega-cities. An Urban Development Land-use Suitability Mapping (UDLSM) approach has been constructed, based on opportunity and constraint criteria. Two Multi-criteria Evaluation (MCE) methods, the Ideal Point Method (IPM) and Ordered Weighted Averaging (OWA), were used to generate the opportunity map. The protection map was obtained by means of constraint criteria, utilizing the Boolean union operator. A suitability map was then generated by overlaying the opportunity and protection maps. By applying the UDLSM approach to Beijing, its urban development land-use suitability was mapped, and a sensitivity analysis undertaken to examine the robustness of the proposed approach. Indirect validation was achieved by mutual comparisons of suitability maps resulting from the two MCE methods, where the overall agreement of 91% and kappa coefficient of 0.78 indicated that both methods provide very similar spatial land-use suitability distributions. The suitability level decreases from central Beijing to its periphery, and the area classed as suitable amounts to 28% of the total area. Leading attributes of each opportunity factor for suitability were revealed, with 2256 km(2), i.e. 70%, of existing development land being overlaid by suitable areas in Beijing. Conflicting parcels of land were identified by overlaying the resultant map with two previous development blueprints for Beijing. The paper includes several recommendations aimed at improving the long-term urban development plans for Beijing.
Phonon lifetime in SiSn and its suitability for hot-carrier solar cells
Levard, Hugo; Laribi, Sana; Guillemoles, Jean-François
2014-06-02
We present a phononic and electronic study of SiSn in the zinc-blende phase. A detailed description of the longitudinal optical (LO) phonon decay in a three-phonon process is presented together with the corresponding lifetime. The necessity to go beyond the zone center phonon approximation in this case is highlighted as it reveals a steep dependence of the lifetime on the initial phonon wavenumber, which differs from usual semiconductors. The electronic band structure is calculated within the GW formalism and shows a small direct band gap. It is shown that the LO-phonon resulting from electron cooling has a lifetime four to eight orders of magnitude above all the known value in semiconductors for this process. We finally show the suitability of SiSn for hot-carrier solar cells, as it is endowed with ultra-slow cooling of hot carriers.
Formal methods in the development of safety critical software systems
Williams, L.G.
1991-11-15
As the use of computers in critical control systems such as aircraft controls, medical instruments, defense systems, missile controls, and nuclear power plants has increased, concern for the safety of those systems has also grown. Much of this concern has focused on the software component of those computer-based systems. This is primarily due to historical experience with software systems that often exhibit larger numbers of errors than their hardware counterparts and the fact that the consequences of a software error may endanger human life, property, or the environment. A number of different techniques have been used to address the issue of software safety. Some are standard software engineering techniques aimed at reducing the number of faults in a software protect, such as reviews and walkthroughs. Others, including fault tree analysis, are based on identifying and reducing hazards. This report examines the role of one such technique, formal methods, in the development of software for safety critical systems. The use of formal methods to increase the safety of software systems is based on their role in reducing the possibility of software errors that could lead to hazards. The use of formal methods in the development of software systems is controversial. Proponents claim that the use of formal methods can eliminate errors from the software development process, and produce programs that are probably correct. Opponents claim that they are difficult to learn and that their use increases development costs unacceptably. This report discusses the potential of formal methods for reducing failures in safety critical software systems.
Silent Partners to Cancer Patients: Formal Caregivers and Oncologists.
Goldzweig, G; Rottenberg, Yakir; Peretz, Tamar; Baider, Lea
2015-12-01
Given the worldwide aging of the population, the projected increase of older people diagnosed with cancer, and the changes in the structure of society and family, it is predictable that larger numbers of aged cancer patients will be supported by formal caregivers. This exploratory study attempts to gain insight into and to make recommendations to oncologists based on the comparison of two groups of foreign formal caregivers-those providing care to elderly cancer patients and those providing care to the elderly suffering from other chronic illnesses. Our sample included 108 Filipino formal caregivers to older persons (age 65+) suffering from cancer or other chronic diseases. Participants completed a short questionnaire targeting background information, subjective perception of distress, attachment to the care recipient family, and the Distress Thermometer. Participants reported extreme levels of distress, with only seven (6.48%) scoring less than 5 on the Distress Thermometer. Caregivers to cancer patients reported significantly higher levels of distress and tended to feel less attached to the family of the patient in comparison to caregivers to patients with other chronic illnesses. Cultural differences regarding cancer among the elderly may explain the higher levels of distress reported among Filipino formal caregivers and need to be acknowledged by oncologists. As a precondition for simultaneously improving the caregiver's well-being and the patient's quality of care, it is recommended that oncologists relate directly to formal caregivers, specifically to their extreme distress and apprehension regarding cancer. PMID:25316613
Proceedings of the Sixth NASA Langley Formal Methods (LFM) Workshop
NASA Technical Reports Server (NTRS)
Rozier, Kristin Yvonne (Editor)
2008-01-01
Today's verification techniques are hard-pressed to scale with the ever-increasing complexity of safety critical systems. Within the field of aeronautics alone, we find the need for verification of algorithms for separation assurance, air traffic control, auto-pilot, Unmanned Aerial Vehicles (UAVs), adaptive avionics, automated decision authority, and much more. Recent advances in formal methods have made verifying more of these problems realistic. Thus we need to continually re-assess what we can solve now and identify the next barriers to overcome. Only through an exchange of ideas between theoreticians and practitioners from academia to industry can we extend formal methods for the verification of ever more challenging problem domains. This volume contains the extended abstracts of the talks presented at LFM 2008: The Sixth NASA Langley Formal Methods Workshop held on April 30 - May 2, 2008 in Newport News, Virginia, USA. The topics of interest that were listed in the call for abstracts were: advances in formal verification techniques; formal models of distributed computing; planning and scheduling; automated air traffic management; fault tolerance; hybrid systems/hybrid automata; embedded systems; safety critical applications; safety cases; accident/safety analysis.
Digital image watermarking: its formal model, fundamental properties and possible attacks
NASA Astrophysics Data System (ADS)
Nyeem, Hussain; Boles, Wageeh; Boyd, Colin
2014-12-01
While formal definitions and security proofs are well established in some fields like cryptography and steganography, they are not as evident in digital watermarking research. A systematic development of watermarking schemes is desirable, but at present, their development is usually informal, ad hoc, and omits the complete realization of application scenarios. This practice not only hinders the choice and use of a suitable scheme for a watermarking application, but also leads to debate about the state-of-the-art for different watermarking applications. With a view to the systematic development of watermarking schemes, we present a formal generic model for digital image watermarking. Considering possible inputs, outputs, and component functions, the initial construction of a basic watermarking model is developed further to incorporate the use of keys. On the basis of our proposed model, fundamental watermarking properties are defined and their importance exemplified for different image applications. We also define a set of possible attacks using our model showing different winning scenarios depending on the adversary capabilities. It is envisaged that with a proper consideration of watermarking properties and adversary actions in different image applications, use of the proposed model would allow a unified treatment of all practically meaningful variants of watermarking schemes.
Do naturalistic enclosures provide suitable environments for zoo animals?
Fàbregas, María C; Guillén-Salazar, Federico; Garcés-Narro, Carlos
2012-01-01
Zoo visitors perceive naturalistic enclosures (i.e. those attempting to replicate identifiable parts of the landscape of the species' habitat) as those that best satisfy the biological needs of the animals, and ensure therefore their welfare. However, the provision of a suitable environment with the resources that will allow the animals to satisfy their main biological needs in naturalistic enclosures has never been systematically explored; instead, it has been assumed. In this study we provide evidence that supports the general idea that naturalistic designs provide suitable environments for the animals. For that purpose, we analyzed 1,381 naturalistic and non-naturalistic enclosures in 63 Spanish zoological parks. In order to assess the suitability of the environment provided within each enclosure, a number of aspects related to the animals' main biological requirements were analyzed. We found a relationship between naturalistic designs and the suitability of the environment for the species housed. Most naturalistic enclosures (77.8%) provided suitable environments for their inhabitants. Non-naturalistic ones also had suitable environments, but in a lower percentage (39.7%). These results should be taken into account during zoo inspection and accreditation appointments, where enclosure suitability must be assessed in an accurate and fast manner. In this regard, a naturalistic design can be used as an adjunct indicator of enclosure suitability, but not exclusively, as not every naturalistic enclosure was suitable for the animals, neither as an indispensable one, given that near 40% of non-naturalistic ones were appropriate for the species housed.
Formal verification of a fault tolerant clock synchronization algorithm
NASA Technical Reports Server (NTRS)
Rushby, John; Vonhenke, Frieder
1989-01-01
A formal specification and mechanically assisted verification of the interactive convergence clock synchronization algorithm of Lamport and Melliar-Smith is described. Several technical flaws in the analysis given by Lamport and Melliar-Smith were discovered, even though their presentation is unusally precise and detailed. It seems that these flaws were not detected by informal peer scrutiny. The flaws are discussed and a revised presentation of the analysis is given that not only corrects the flaws but is also more precise and easier to follow. Some of the corrections to the flaws require slight modifications to the original assumptions underlying the algorithm and to the constraints on its parameters, and thus change the external specifications of the algorithm. The formal analysis of the interactive convergence clock synchronization algorithm was performed using the Enhanced Hierarchical Development Methodology (EHDM) formal specification and verification environment. This application of EHDM provides a demonstration of some of the capabilities of the system.
Formalizing New Navigation Requirements for NASA's Space Shuttle
NASA Technical Reports Server (NTRS)
DiVito, Ben L.
1996-01-01
We describe a recent NASA-sponsored pilot project intended to gauge the effectiveness of using formal methods in Space Shuttle software requirements analysis. Several Change Requests (CRs) were selected as promising targets to demonstrate the utility of formal methods in this demanding application domain. A CR to add new navigation capabilities to the Shuttle, based on Global Positioning System (GPS) technology, is the focus of this industrial usage report. Portions of the GPS CR were modeled using the language of SRI's Prototype Verification System (PVS). During a limited analysis conducted on the formal specifications, numerous requirements issues were discovered. We present a summary of these encouraging results and conclusions we have drawn from the pilot project.
Formal Verification of the AAMP-FV Microcode
NASA Technical Reports Server (NTRS)
Miller, Steven P.; Greve, David A.; Wilding, Matthew M.; Srivas, Mandayam
1999-01-01
This report describes the experiences of Collins Avionics & Communications and SRI International in formally specifying and verifying the microcode in a Rockwell proprietary microprocessor, the AAMP-FV, using the PVS verification system. This project built extensively on earlier experiences using PVS to verify the microcode in the AAMP5, a complex, pipelined microprocessor designed for use in avionics displays and global positioning systems. While the AAMP5 experiment demonstrated the technical feasibility of formal verification of microcode, the steep learning curve encountered left unanswered the question of whether it could be performed at reasonable cost. The AAMP-FV project was conducted to determine whether the experience gained on the AAMP5 project could be used to make formal verification of microcode cost effective for safety-critical and high volume devices.
An envelope function formalism for lattice-matched heterostructures
NASA Astrophysics Data System (ADS)
Van de Put, Maarten L.; Vandenberghe, William G.; Magnus, Wim; Sorée, Bart
2015-08-01
The envelope function method traditionally employs a single basis set which, in practice, relates to a single material because the k · p matrix elements are generally only known in a particular basis. In this work, we defined a basis function transformation to alleviate this restriction. The transformation is completely described by the known inter-band momentum matrix elements. The resulting envelope function equation can solve the electronic structure in lattice matched heterostructures without resorting to boundary conditions at the interface between materials, while all unit-cell averaged observables can be calculated as with the standard envelope function formalism. In the case of two coupled bands, this heterostructure formalism is equivalent to the standard formalism while taking position dependent matrix elements.
Formal Grammars for Product Data Management on Distributed Manufacturing Systems
NASA Astrophysics Data System (ADS)
Sousa, Rui M.; Martins, Paulo J.; Lima, Rui M.
This work shows how formal grammars with attributes can be advantageously used to deal with two fundamental aspects of product data management - product diversity management and generation of specific product data based on clients’ specification - in the context of distributed manufacturing systems, while networks of geographically distant collaborative entities. This contribution will constitute a new component for an existing model, developed by the authors, for dynamic production planning and control which includes the interoperability with industrial equipment. The proposed approach is centered on attributed formal grammars, allowing the formalization of the data representation for each family of products and also of some of the inherent processing (e.g. generation of specific products’ bill-of-materials).
Pedagogical basis of DAS formalism in engineering education
NASA Astrophysics Data System (ADS)
Hiltunen, J.; Heikkinen, E.-P.; Jaako, J.; Ahola, J.
2011-03-01
The paper presents a new approach for a bachelor-level curriculum structure in engineering. The approach is called DAS formalism according to its three phases: description, analysis and synthesis. Although developed specifically for process and environmental engineering, DAS formalism has a generic nature and it could also be used in other engineering fields. The motivation for this new curriculum structure originates from the urge to solve the problems that engineering education has faced during the past decades, e.g. student recruitment problems and dissatisfactory learning outcomes. The focus of this paper is on the structure of the curriculum but the content is also discussed when it has an effect on the structure and its implementation. The presented structure, i.e. DAS formalism, builds upon the ideas of some classical pedagogical theories, which have regularly been applied at course level but seldom used to solve curriculum-level issues.
Formal mechanization of device interactions with a process algebra
NASA Technical Reports Server (NTRS)
Schubert, E. Thomas; Levitt, Karl; Cohen, Gerald C.
1992-01-01
The principle emphasis is to develop a methodology to formally verify correct synchronization communication of devices in a composed hardware system. Previous system integration efforts have focused on vertical integration of one layer on top of another. This task examines 'horizontal' integration of peer devices. To formally reason about communication, we mechanize a process algebra in the Higher Order Logic (HOL) theorem proving system. Using this formalization we show how four types of device interactions can be represented and verified to behave as specified. The report also describes the specification of a system consisting of an AVM-1 microprocessor and a memory management unit which were verified in previous work. A proof of correct communication is presented, and the extensions to the system specification to add a direct memory device are discussed.
A reanalysis of a strong-flow gyrokinetic formalism
Sharma, A. Y.; McMillan, B. F.
2015-03-15
We reanalyse an arbitrary-wavelength gyrokinetic formalism [A. M. Dimits, Phys. Plasmas 17, 055901 (2010)], which orders only the vorticity to be small and allows strong, time-varying flows on medium and long wavelengths. We obtain a simpler gyrocentre Lagrangian up to second order. In addition, the gyrokinetic Poisson equation, derived either via variation of the system Lagrangian or explicit density calculation, is consistent with that of the weak-flow gyrokinetic formalism [T. S. Hahm, Phys. Fluids 31, 2670 (1988)] at all wavelengths in the weak flow limit. The reanalysed formalism has been numerically implemented as a particle-in-cell code. An iterative scheme is described which allows for numerical solution of this system of equations, given the implicit dependence of the Euler-Lagrange equations on the time derivative of the potential.
Formally Verified Practical Algorithms for Recovery from Loss of Separation
NASA Technical Reports Server (NTRS)
Butler, Ricky W.; Munoz, Caesar A.
2009-01-01
In this paper, we develop and formally verify practical algorithms for recovery from loss of separation. The formal verification is performed in the context of a criteria-based framework. This framework provides rigorous definitions of horizontal and vertical maneuver correctness that guarantee divergence and achieve horizontal and vertical separation. The algorithms are shown to be independently correct, that is, separation is achieved when only one aircraft maneuvers, and implicitly coordinated, that is, separation is also achieved when both aircraft maneuver. In this paper we improve the horizontal criteria over our previous work. An important benefit of the criteria approach is that different aircraft can execute different algorithms and implicit coordination will still be achieved, as long as they all meet the explicit criteria of the framework. Towards this end we have sought to make the criteria as general as possible. The framework presented in this paper has been formalized and mechanically verified in the Prototype Verification System (PVS).
Weak Quantum Theory: Formal Framework and Selected Applications
Atmanspacher, Harald; Filk, Thomas; Roemer, Hartmann
2006-01-04
Two key concepts of quantum theory, complementarity and entanglement, are considered with respect to their significance in and beyond physics. An axiomatically formalized, weak version of quantum theory, more general than the ordinary quantum theory of physical systems, is described. Its mathematical structure generalizes the algebraic approach to ordinary quantum theory. The crucial formal feature leading to complementarity and entanglement is the non-commutativity of observables.The ordinary Hilbert space quantum mechanics can be recovered by stepwise adding the necessary features. This provides a hierarchy of formal frameworks of decreasing generality and increasing specificity. Two concrete applications, more specific than weak quantum theory and more general than ordinary quantum theory, are discussed: (i) complementarity and entanglement in classical dynamical systems, and (ii) complementarity and entanglement in the bistable perception of ambiguous stimuli.
A Formal Approach to Requirements-Based Programming
NASA Technical Reports Server (NTRS)
Hinchey, Michael G.; Rash, James L.; Rouff, Christopher A.
2005-01-01
No significant general-purpose method is currently available to mechanically transform system requirements into a provably equivalent model. The widespread use of such a method represents a necessary step toward high-dependability system engineering for numerous application domains. Current tools and methods that start with a formal model of a system and mechanically produce a provably equivalent implementation are valuable but not sufficient. The "gap" unfilled by such tools and methods is that the formal models cannot be proven to be equivalent to the requirements. We offer a method for mechanically transforming requirements into a provably equivalent formal model that can be used as the basis for code generation and other transformations. This method is unique in offering full mathematical tractability while using notations and techniques that are well known and well trusted. Finally, we describe further application areas we are investigating for use of the approach.
Matrix formalism for current-independent optics design.
Wang, C.-x.; Kim, K.-J.; Accelerator Systems Division
2006-01-01
Matrix formalism has been a powerful tool for beam optics designs. It not only facilitates computations but also plays an important role in formulating various design concepts. Here we extend the standard matrix formalism for the purpose of designing an optics that transports space-charge-dominated intense beam. Furthermore, we explore the concept of current-independent optics, which can be useful for systems such as high-brightness injectors and space-charge-dominated rings. Our discussion here is preliminary and limited to axisymmetric systems.
Unified formalism for higher order non-autonomous dynamical systems
NASA Astrophysics Data System (ADS)
Prieto-Martínez, Pedro Daniel; Román-Roy, Narciso
2012-03-01
This work is devoted to giving a geometric framework for describing higher order non-autonomous mechanical systems. The starting point is to extend the Lagrangian-Hamiltonian unified formalism of Skinner and Rusk for these kinds of systems, generalizing previous developments for higher order autonomous mechanical systems and first-order non-autonomous mechanical systems. Then, we use this unified formulation to derive the standard Lagrangian and Hamiltonian formalisms, including the Legendre-Ostrogradsky map and the Euler-Lagrange and the Hamilton equations, both for regular and singular systems. As applications of our model, two examples of regular and singular physical systems are studied.
Skinner Rusk unified formalism for optimal control systems and applications
NASA Astrophysics Data System (ADS)
Barbero-Liñán, María; Echeverría-Enríquez, Arturo; Martín de Diego, David; Muñoz-Lecanda, Miguel C.; Román-Roy, Narciso
2007-10-01
A geometric approach to time-dependent optimal control problems is proposed. This formulation is based on the Skinner and Rusk formalism for Lagrangian and Hamiltonian systems. The corresponding unified formalism developed for optimal control systems allows us to formulate geometrically the necessary conditions given by a weak form of Pontryagin's maximum principle, provided that the differentiability with respect to controls is assumed and the space of controls is open. Furthermore, our method is also valid for implicit optimal control systems and, in particular, for the so-called descriptor systems (optimal control problems including both differential and algebraic equations).
A proposed formal structure for assessing bear-human encounters
NASA Astrophysics Data System (ADS)
Kerr, William A.; Wilman, Elizabeth A.
1988-03-01
A formal model for the interaction of bear and hiker populations in national parks is developed. A number of alternative interactive scenarios are identified and some specific cases explored in detail. Some examples of the insights to be gained by the use of such a formal structure by park managers charged with the dual mandate of preservation of fauna and provision of safe recreational opportunities are presented. The entire problem is then discussed within the context of the more general “tragedy of the commons” problem.
Sudakov resummation in the small-x saturation formalism.
Mueller, A H; Xiao, Bo-Wen; Yuan, Feng
2013-02-22
Through an explicit calculation of massive scalar particle (e.g., Higgs boson) production in high energy pA collisions up to one-loop order, we demonstrate, for the first time, that the Sudakov-type logarithms in hard processes in the small-x saturation formalism can be systematically separated from the small-x logarithms. The generic feature of the Sudakov logarithms and all order resummation is derived. This calculation shall provide us deep insights into the understanding of factorizations in the saturation formalism. We further comment on the phenomenological implications in the LHC energy regime and extension to other hard processes in small-x calculations.
Formal training in forensic mental health: psychiatry and psychology.
Sadoff, Robert L; Dattilio, Frank M
2012-01-01
The field of forensic mental health has grown exponentially in the past decades to include forensic psychiatrists and psychologists serving as the primary experts to the court systems. However, many colleagues have chosen to pursue the avenue of serving as forensic experts without obtaining formal training and experience. This article discusses the importance of formal education, training and experience for psychiatrists and psychologists working in forensic settings and the ethical implications that befall those who fail to obtain such credentials. Specific aspects of training and supervised experience are discussed in detail.
Manifesting color-kinematics duality in the scattering equation formalism
NASA Astrophysics Data System (ADS)
Bjerrum-Bohr, N. E. J.; Bourjaily, Jacob L.; Damgaard, Poul H.; Feng, Bo
2016-09-01
We prove that the scattering equation formalism for Yang-Mills amplitudes can be used to make manifest the theory's color-kinematics duality. This is achieved through a concrete reduction algorithm which renders this duality manifest term-by-term. The reduction follows from the recently derived set of identities for amplitudes expressed in the scattering equation formalism that are analogous to monodromy relations in string theory. A byproduct of our algorithm is a generalization of the identities among gravity and Yang-Mills amplitudes.
The generation of gravitational waves. II - The postlinear formalism revisited
NASA Technical Reports Server (NTRS)
Crowley, R. J.; Thorne, K. S.
1977-01-01
Two different versions of the Green's function for the scalar wave equation in weakly curved spacetime (one due to DeWitt and DeWitt, the other to Thorne and Kovacs) are compared and contrasted; and their mathematical equivalence is demonstrated. Then the DeWitt-DeWitt Green's function is used to construct several alternative versions of the Thorne-Kovacs postlinear formalism for gravitational-wave generation. Finally it is shown that, in calculations of gravitational bremsstrahlung radiation, some of our versions of the postlinear formalism allow one to treat the interacting bodies as point masses, while others do not.
36 CFR 219.26 - Identifying and designating suitable uses.
Code of Federal Regulations, 2011 CFR
2011-07-01
... AGRICULTURE PLANNING National Forest System Land and Resource Management Planning Special Considerations § 219.26 Identifying and designating suitable uses. National forests and grasslands are suitable for a wide... incompatible with the mission or policies of the National Forest System; or would result in substantial...
28 CFR 2.73 - Parole suitability criteria.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 28 Judicial Administration 1 2014-07-01 2014-07-01 false Parole suitability criteria. 2.73 Section 2.73 Judicial Administration DEPARTMENT OF JUSTICE PAROLE, RELEASE, SUPERVISION AND RECOMMITMENT OF....73 Parole suitability criteria. (a) In accordance with D.C. Code 24-404(a), the Commission shall...
28 CFR 2.73 - Parole suitability criteria.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 28 Judicial Administration 1 2012-07-01 2012-07-01 false Parole suitability criteria. 2.73 Section 2.73 Judicial Administration DEPARTMENT OF JUSTICE PAROLE, RELEASE, SUPERVISION AND RECOMMITMENT OF....73 Parole suitability criteria. (a) In accordance with D.C. Code 24-404(a), the Commission shall...
28 CFR 2.73 - Parole suitability criteria.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 28 Judicial Administration 1 2013-07-01 2013-07-01 false Parole suitability criteria. 2.73 Section 2.73 Judicial Administration DEPARTMENT OF JUSTICE PAROLE, RELEASE, SUPERVISION AND RECOMMITMENT OF....73 Parole suitability criteria. (a) In accordance with D.C. Code 24-404(a), the Commission shall...
28 CFR 2.73 - Parole suitability criteria.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 28 Judicial Administration 1 2011-07-01 2011-07-01 false Parole suitability criteria. 2.73 Section 2.73 Judicial Administration DEPARTMENT OF JUSTICE PAROLE, RELEASE, SUPERVISION AND RECOMMITMENT OF....73 Parole suitability criteria. (a) In accordance with D.C. Code 24-404(a), the Commission shall...
30 CFR 75.515 - Cable fittings; suitability.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Cable fittings; suitability. 75.515 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.515 Cable fittings; suitability. Cables shall enter metal frames of motors, splice boxes, and electric...
30 CFR 77.505 - Cable fittings; suitability.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Cable fittings; suitability. 77.505 Section 77... Electrical Equipment-General § 77.505 Cable fittings; suitability. Cables shall enter metal frames of motors... cables, pass through metal frames, the holes shall be substantially bushed with insulated bushings....
21 CFR 640.31 - Suitability of donors.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Suitability of donors. 640.31 Section 640.31 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Plasma § 640.31 Suitability of donors. (a)...
21 CFR 640.63 - Suitability of donor.
Code of Federal Regulations, 2010 CFR
2010-04-01
... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Source Plasma § 640.63 Suitability of donor. (a) Method of determining. The suitability of a donor for Source Plasma shall be determined by a qualified... year. (2)(i) A donor who is to be immunized for the production of high-titer plasma shall be...
21 CFR 640.31 - Suitability of donors.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 7 2011-04-01 2010-04-01 true Suitability of donors. 640.31 Section 640.31 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Plasma § 640.31 Suitability of donors. (a)...
21 CFR 640.63 - Suitability of donor.
Code of Federal Regulations, 2011 CFR
2011-04-01
... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Source Plasma § 640.63 Suitability of donor. (a) Method of determining. The suitability of a donor for Source Plasma shall be determined by a qualified... year. (2)(i) A donor who is to be immunized for the production of high-titer plasma shall be...
21 CFR 640.31 - Suitability of donors.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 21 Food and Drugs 7 2012-04-01 2012-04-01 false Suitability of donors. 640.31 Section 640.31 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Plasma § 640.31 Suitability of donors. (a)...
21 CFR 640.63 - Suitability of donor.
Code of Federal Regulations, 2012 CFR
2012-04-01
... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Source Plasma § 640.63 Suitability of donor. (a) Method of determining. The suitability of a donor for Source Plasma shall be determined by a qualified... year. (2)(i) A donor who is to be immunized for the production of high-titer plasma shall be...
21 CFR 640.63 - Suitability of donor.
Code of Federal Regulations, 2013 CFR
2013-04-01
... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Source Plasma § 640.63 Suitability of donor. (a) Method of determining. The suitability of a donor for Source Plasma shall be determined by a qualified... year. (2)(i) A donor who is to be immunized for the production of high-titer plasma shall be...