Sample records for biquadratic assignment problem

  1. Cognitive-graphic method for constructing of hierarchical forms of basic functions of biquadratic finite element

    NASA Astrophysics Data System (ADS)

    Astionenko, I. O.; Litvinenko, O. I.; Osipova, N. V.; Tuluchenko, G. Ya.; Khomchenko, A. N.

    2016-10-01

    Recently the interpolation bases of the hierarchical type have been used for the problem solving of the approximation of multiple arguments functions (such as in the finite-element method). In this work the cognitive graphical method of constructing of the hierarchical form bases on the serendipity finite elements is suggested, which allowed to get the alternative bases on a biquadratic finite element from the serendipity family without internal knots' inclusion. The cognitive-graphic method allowed to improve the known interpolation procedure of Taylor and to get the modified elements with irregular arrangement of knots. The proposed procedures are universal and are spread in the area of finite-elements.

  2. A Monte Carlo study of the spin-1 Blume-Emery-Griffiths phase diagrams within biquadratic exchange anisotropy

    NASA Astrophysics Data System (ADS)

    Dani, Ibtissam; Tahiri, Najim; Ez-Zahraouy, Hamid; Benyoussef, Abdelilah

    2014-08-01

    The effect of the bi-quadratic exchange coupling anisotropy on the phase diagram of the spin-1 Blume-Emery-Griffiths model on simple-cubic lattice is investigated using mean field theory (MFT) and Monte Carlo simulation (MC). It is found that the anisotropy of the biquadratic coupling favors the stability of the ferromagnetic phase. By decreasing the parallel and/or perpendicular bi-quadratic coupling, the ferrimagnetic and the antiquadrupolar phases broaden in contrast, the ferromagnetic and the disordered phases become narrow. The behavior of magnetization and quadrupolar moment as a function of temperature is also computed, especially in the ferrimagnetic phase.

  3. Effect of biquadratic coupling on current induced magnetization switching in Co/Cu/Ni-Fe nanopillar

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

    Aravinthan, D.; Daniel, M., E-mail: danielcnld@gmail.com; Sabareesan, P.

    2016-05-23

    The effect of biquadratic coupling on spin current induced magnetization switching in a Co/Cu/Ni-Fe nanopillar device is investigated by solving the free layer magnetization switching dynamics governed by the Landau-Lifshitz-Gilbert-Slonczewski (LLGS) equation. The LLGS equation is numerically solved by using Runge-Kutta fourth order procedure for an applied current density of 5 × 10{sup 12} Am{sup -2}. Presence of biquadratic coupling in the ferromagnetic layers reduces the magnetization switching time of the nanopillar device from 61 ps to 49 ps.

  4. Bi-quadratic interlayer exchange coupling in Co{sub 2}MnSi/Ag/Co{sub 2}MnSi pseudo spin-valve

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

    Goripati, Hari S.; Hono, K.; Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba 305-0047

    2011-12-15

    Bi-quadratic interlayer exchange coupling is found below 100 K in a Co{sub 2}MnSi/Ag/Co{sub 2}MnSi current-perpendicular-to-plane pseudo spin valves. The bi-quadratic coupling constant J{sub 2} was estimated to be {approx}-0.30 erg/cm{sup 2} at 5 K and the strong temperature dependence of the coupling strength points its likely origin to the ''loose spin'' model. Application of current of {approx}2 x 10{sup 7} A/cm{sup 2} below 100 K leads to an increase in the magnetoresistance (MR), indicating current induced antiparallel alignment of the two magnetic layers. These results strongly suggest that the presence of the bi-quadratic interlayer exchange coupling causes the reduction ofmore » the magnetoresistance at low temperature and illustrates the importance of understanding the influence of interlayer exchange coupling on magnetization configuration in magnetic nanostructures.« less

  5. The bilinear-biquadratic model on the complete graph

    NASA Astrophysics Data System (ADS)

    Jakab, Dávid; Szirmai, Gergely; Zimborás, Zoltán

    2018-03-01

    We study the spin-1 bilinear-biquadratic model on the complete graph of N sites, i.e. when each spin is interacting with every other spin with the same strength. Because of its complete permutation invariance, this Hamiltonian can be rewritten as the linear combination of the quadratic Casimir operators of \

  6. Energy as Entanglement Witness in Bilinear-Biquadratic Spin-1 Chain

    NASA Astrophysics Data System (ADS)

    Xu, Feng; Wang, An-Min; Zhao, Ning-Bo; Su, Xiao-Qiang; Zhu, Ren-Gui

    2006-10-01

    Energy is introduced as an entanglement witness to describe the entanglement property of a quantum system. The thermal equilibrium system is guaranteed to be entangled when system is cooled down below the entanglement temperature TE. By virtue of this concept we exploit the minimum separable state energy and entanglement temperature TE of the bilinear-biquadratic antiferromagnetic spin-1 chain model. We numerically calculate TE for arbitrary values of the strength of biquadratic exchange interaction Q up to N = 7. We find TE decreases with Q for fixed N when Q is between -3 and 1/3 (J = 1). In this regime TE also decreases with N for fixed Q and varies slowly for large N. While the thermal system is always entangled when Q is smaller than -3.

  7. Chaotic dynamics of Heisenberg ferromagnetic spin chain with bilinear and biquadratic interactions

    NASA Astrophysics Data System (ADS)

    Blessy, B. S. Gnana; Latha, M. M.

    2017-10-01

    We investigate the chaotic dynamics of one dimensional Heisenberg ferromagnetic spin chain by constructing the Hamiltonian equations of motion. We present the trajectory and phase plots of the system with bilinear and also biquadratic interactions. The stability of the system is analysed in both cases by constructing the Jacobian matrix and by measuring the Lyapunov exponents. The results are illustrated graphically.

  8. Biquadratic coupling through nano-oxide layers in pinned layers of IrMn-based spin valves

    NASA Astrophysics Data System (ADS)

    Lai, Chih-Huang; Lu, K. H.

    2003-05-01

    We have investigated the coupling between top and bottom pinned layers through various nano-oxide layers (NOLs) in IrMn-based spin valves. The NOLs were formed by using oxygen-plasma oxidation or natural oxidation on 1 nm metallic layers. By inserting naturally oxidized Co-NOLs in the pinned layer, strong ferromagnetic coupling through NOLs and high specularity at the NOL interface were achieved. In contrast, when the plasma-oxidized Co-NOLs were inserted, ferromagnetic coupling through NOLs disappeared, plausibly due to the formation of nonferromagnetic oxides, which led to a low magnetoresistance (MR). Insertion of naturally oxidized Ni80Fe20-NOLs showed the same results as that of naturally oxidized Co-NOLs. On the other hand, biquadratic coupling between top and bottom pinned-Co90Fe10 layers was observed by inserting plasma-oxidized Ni80Fe20-NOLs. The highest MR was obtained when the field was applied along the direction perpendicular to the field-annealing direction. Similar biquadratic coupling was also found with naturally oxidized or plasma-oxidized Fe-NOLs. We suggest that the biquadratic coupling between pinned Co90Fe10 layers through NOLs results from the coupling between Fe (or Co90Fe10) and Fe+3 oxides

  9. A bivariate rational interpolation with a bi-quadratic denominator

    NASA Astrophysics Data System (ADS)

    Duan, Qi; Zhang, Huanling; Liu, Aikui; Li, Huaigu

    2006-10-01

    In this paper a new rational interpolation with a bi-quadratic denominator is developed to create a space surface using only values of the function being interpolated. The interpolation function has a simple and explicit rational mathematical representation. When the knots are equally spaced, the interpolating function can be expressed in matrix form, and this form has a symmetric property. The concept of integral weights coefficients of the interpolation is given, which describes the "weight" of the interpolation points in the local interpolating region.

  10. Spin-one bilinear-biquadratic model on a star lattice

    NASA Astrophysics Data System (ADS)

    Lee, Hyun-Yong; Kawashima, Naoki

    2018-05-01

    We study the ground-state phase diagram of the S =1 bilinear-biquadratic model (BLBQ) on the star lattice with the state-of-art tensor network algorithms. The system has four phases: the ferromagnetic, antiferromagnetic, ferroquadrupolar, and spin-liquid phases. The phases and their phase boundaries are determined by examining various local observables, correlation functions, and transfer matrices exhaustively. The spin-liquid phase, which is the first quantum disordered phase found in the two-dimensional BLBQ model, is gapped and devoid of any conventional long-range order. It is also characterized by fixed-parity virtual bonds in the tensor network formalism, analogous to the Haldane phase, while the parity varies depending on the location of the bond.

  11. Effect of magnetic field on noncollinear magnetism in classical bilinear-biquadratic Heisenberg model

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

    Pasrija, Kanika, E-mail: kanikapasrija@iisermohali.ac.in; Kumar, Sanjeev, E-mail: sanjeev@iisermohali.ac.in

    We present a Monte Carlo simulation study of a bilinear-biquadratic Heisenberg model on a two-dimensional square lattice in the presence of an external magnetic field. The study is motivated by the relevance of this simple model to the non-collinear magnetism and the consequent ferroelectric behavior in the recently discovered high-temperature multiferroic, cupric oxide (CuO). We show that an external magnetic field stabilizes a non-coplanar magnetic phase, which is characterized by a finite ferromagnetic moment along the direction of the applied magnetic field and a spiral spin texture if projected in the plane perpendicular to the magnetic field. Real-space analysis highlightsmore » a coexistence of non-collinear regions with ferromagnetic clusters. The results are also supported by simple variational calculations.« less

  12. Random Blume-Emery-Griffiths model on the Bethe lattice

    NASA Astrophysics Data System (ADS)

    Albayrak, Erhan

    2015-12-01

    The random phase transitions of the Blume-Emery-Griffiths (BEG) model for the spin-1 system are investigated on the Bethe lattice and the phase diagrams of the model are obtained. The biquadratic exchange interaction (K) is turned on, i.e. the BEG model, with probability p either attractively (K > 0) or repulsively (K < 0) and turned off, which leads to the BC model, with the probability (1 - p) throughout the Bethe lattice. By taking the bilinear exchange interaction parameter J as a scaling parameter, the effects of the competitions between the reduced crystal fields (D / J), reduced biquadratic exchange interaction parameter (K / J) and the reduced temperature (kT / J) for given values of the probability when the coordination number is q=4, i.e. on a square lattice, are studied in detail.

  13. Generalized spin-wave theory: Application to the bilinear-biquadratic model

    NASA Astrophysics Data System (ADS)

    Muniz, Rodrigo A.; Kato, Yasuyuki; Batista, Cristian D.

    2014-08-01

    We present a mathematical framework for the multi-boson approach that has been used several times for treating spin systems. We demonstrate that the multi-boson approach corresponds to a generalization of the traditional spin-wave theory from SU(2) to SU(N), where N is the number of states of the local degree of freedom. Low-energy excitations are waves of the local order parameter that fluctuates in the SU(N) space of unitary transformations of the local spin states, instead of the SU(2) space of local spin rotations. Since the generators of the SU(N) group can be represented as bilinear forms in N-flavored bosons, the low-energy modes of the generalized spin-wave theory (GSWT) are described with N-1 different bosons, which provide a more accurate description of low-energy excitations even for the usual ferromagnetic and antiferromagnetic phases. The generalization enables the treatment of quantum spin systems whose ground states exhibit multipolar ordering as well as the detection of instabilities of magnetically ordered states (dipolar ordering) towards higher multipolar orderings. We illustrate the advantages of the GSWT by applying it to a bilinear-biquadratic model of arbitrary spin S on hypercubic lattices, and then analyzing the spectrum of dipolar phases in order to find their instabilities. In contrast to the known results for S=1 when the biquadratic term in the Hamiltonian is negative, we find that there is no nematic phase between the ferromagnetic or antiferromagnetic orderings for S>1.

  14. NASTRAN implementation of an isoparametric doubly-curved quadrilateral shell element

    NASA Technical Reports Server (NTRS)

    Potvin, A. B.; Leick, R. D.

    1978-01-01

    A quadrilateral shell element, CQUAD4, was added to level 15.5 and subsequently to level 16.0 of NASTRAN. The element exhibited doubly curved surfaces and used biquadratic interpolation functions. Reduced integration techniques were used to improve the performance of the element in thin shell problems. The creation of several new bulk data items is discussed, along with a special module, GPNORM, to process SHLNORM bulk data cards. In addition to the theoretical basis for the element stiffness matrix, consistent mass and load matrices are presented. Several potential sources of degenerate behavior of the element were investigated. Guidelines for proper use of the element were suggested. Performance of the element on several widely published classical examples was demonstrated. The results showed a significant improvement over presently available NASTRAN shell elements for even the coarsest meshes. Potential applications to two classes of practical problems are discussed.

  15. Spin wave propagation spectra in Octonacci one-dimensional magnonic quasicrystals

    NASA Astrophysics Data System (ADS)

    Valeriano, Analine P.; Costa, Carlos H.; Bezerra, Claudionor G.

    2018-06-01

    In this paper, we study spin wave propagation in quasiperiodic magnonic superlattices that follow the so-called Octonacci quasiperiodic sequence, where the N-th stage can be obtained through the recurrence rule SN =SN-1SN-2SN-1 , for N ⩾ 3 , and starting with S1 = A and S2 = B . The multilayered magnonic nanostructure is composed of two simple cubic ferromagnetic materials, labeled A and B, which interact through bilinear and biquadratic exchange couplings at their interfaces. The ferromagnetic materials are described by the Heisenberg model, and a transfer matrix treatment is employed, with the calculations performed for the exchange-dominated regime, taking the random phase approximation (RPA) into account. The obtained numerical results show the effects of both (i) the Octonacci quasiperiodic sequence and (ii) the biquadratic exchange coupling on the band structure and transmission spectra of spin waves. Comparisons are also performed with the spectra found in other periodic and quasiperiodic structures.

  16. Interesting features of nonlinear shock equations in dissipative pair-ion-electron plasmas

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

    Masood, W.; National Centre for Physics; Rizvi, H.

    2011-09-15

    Two dimensional nonlinear electrostatic waves are studied in unmagnetized, dissipative pair-ion-electron plasmas in the presence of weak transverse perturbation. The dissipation in the system is taken into account by incorporating the kinematic viscosity of both positive and negative ions. In the linear case, a biquadratic dispersion relation is obtained, which yields the fast and slow modes in a pair-ion-electron plasma. It is shown that the limiting cases of electron-ion and pair-ion can be retrieved from the general biquadratic dispersion relation, and the differences in the characters of the waves propagating in both the cases are also highlighted. Using the smallmore » amplitude approximation method, the nonlinear Kadomtsev Petviashvili Burgers as well as Burgers-Kadomtsev Petviashvili equations are derived and their applicability for pair-ion-electron plasma is explained in detail. The present study may have relevance to understand the formation of two dimensional electrostatic shocks in laboratory produced pair-ion-electron plasmas.« less

  17. Vector magnetometry of Fe/Cr/Fe trilayers with biquadratic coupling

    NASA Astrophysics Data System (ADS)

    Mansell, R.; Petit, D.; Fernández-Pacheco, A.; Lee, J. H.; Chin, S.-L.; Lavrijsen, R.; Cowburn, R. P.

    2017-05-01

    The magnetic reversal of epitaxial Fe/Cr/Fe trilayer samples grown on GaAs is studied. In wedged samples both long and short period coupling oscillations associated with Ruderman-Kittel-Kasuya-Yosida (RKKY) coupling in Cr are seen in the easy axis saturation fields. By using vector vibrating sample magnetometry and both longitudinal and transverse magneto-optical Kerr effect magnetometry we are able to determine the exact reversal path of both the magnetic layers. Changes in the reversal behavior are seen with sub-monolayer changes of the thickness of the Cr interlayer. The two main reversal paths are described in terms of whether the reversal is dominated by bilinear RKKY coupling, which leads to an antiparallel state at remanence or by biquadratic coupling which leads to a 90 degree alignment of layers at remanence. The changing reversal behaviour is discussed with respect to the possibility of using such systems for multilayer memory applications and, in particular, the limits on the required accuracy of the sample growth.

  18. Monte Carlo simulations of the spin-2 Blume-Emery-Griffiths model with four-spin interactions

    NASA Astrophysics Data System (ADS)

    Jabar, A.; Masrour, R.; Jetto, K.; Bahmad, L.; Benyoussef, A.; Hamedoun, M.

    2016-12-01

    The magnetic properties of a spin S = 2 Ising system with bilinear exchange interaction J1, the biquadratic exchange interaction K, four-spin exchange interactions J4 and crystal field Δ are discussed using the Monte Carlo simulation. The lattice is divided into two sublattices: A and B, for which we compute the magnetizations mA and mB. The phase obtained diagrams of this system are deduced in the planes: (T, Δ/J1), (K/J1, Δ/J1), (Δ/J1, J4/J1) and (J4/J1, K/J1). In addition to the usual phases, we found a new phase called nonmagnetic quadratic, for which the magnetizations are mA ≠ mB and the quadrupolar moments are so that are qA = qB. Furthermore, the behavior of the magnetizations as a function of temperature, crystal field, four-spin exchange interactions and biquadratic exchange interaction are deduced.

  19. A spin rotator model for Heisenberg helimagnet

    NASA Astrophysics Data System (ADS)

    Felcy, A. Ludvin; Latha, M. M.

    2018-02-01

    We study the dynamics of a helimagnetic spin system by proposing a spin rotator model taking into account bilinear, twist interplane and anisotropic interactions in the continuum limit. The dynamical equations of motion are obtained and studied numerically. The influence of different types of inhomogeneities is also analysed. Similar studies are carried out for the system including biquadratic type interactions.

  20. Versatile tunable current-mode universal biquadratic filter using MO-DVCCs and MOSFET-based electronic resistors.

    PubMed

    Chen, Hua-Pin

    2014-01-01

    This paper presents a versatile tunable current-mode universal biquadratic filter with four-input and three-output employing only two multioutput differential voltage current conveyors (MO-DVCCs), two grounded capacitors, and a well-known method for replacement of three grounded resistors by MOSFET-based electronic resistors. The proposed configuration exhibits high-output impedance which is important for easy cascading in the current-mode operations. The proposed circuit can be used as either a two-input three-output circuit or a three-input single-output circuit. In the operation of two-input three-output circuit, the bandpass, highpass, and bandreject filtering responses can be realized simultaneously while the allpass filtering response can be easily obtained by connecting appropriated output current directly without using additional stages. In the operation of three-input single-output circuit, all five generic filtering functions can be easily realized by selecting different three-input current signals. The filter permits orthogonal controllability of the quality factor and resonance angular frequency, and no inverting-type input current signals are imposed. All the passive and active sensitivities are low. Postlayout simulations were carried out to verify the functionality of the design.

  1. Versatile Tunable Current-Mode Universal Biquadratic Filter Using MO-DVCCs and MOSFET-Based Electronic Resistors

    PubMed Central

    2014-01-01

    This paper presents a versatile tunable current-mode universal biquadratic filter with four-input and three-output employing only two multioutput differential voltage current conveyors (MO-DVCCs), two grounded capacitors, and a well-known method for replacement of three grounded resistors by MOSFET-based electronic resistors. The proposed configuration exhibits high-output impedance which is important for easy cascading in the current-mode operations. The proposed circuit can be used as either a two-input three-output circuit or a three-input single-output circuit. In the operation of two-input three-output circuit, the bandpass, highpass, and bandreject filtering responses can be realized simultaneously while the allpass filtering response can be easily obtained by connecting appropriated output current directly without using additional stages. In the operation of three-input single-output circuit, all five generic filtering functions can be easily realized by selecting different three-input current signals. The filter permits orthogonal controllability of the quality factor and resonance angular frequency, and no inverting-type input current signals are imposed. All the passive and active sensitivities are low. Postlayout simulations were carried out to verify the functionality of the design. PMID:24982963

  2. Versatile current-mode universal biquadratic filter using DO-CCIIs

    NASA Astrophysics Data System (ADS)

    Chen, Hua-Pin

    2013-07-01

    In this article, a new three-input and three-output versatile current-mode universal biquadratic filter is proposed. The circuit employs three dual-output current conveyors (DO-CCIIs) as active elements together with three grounded resistors and two grounded capacitors. The proposed configuration exhibits low-input impedance and high-output impedance which is important for easy cascading in the current-mode operations. It can be used as either a single-input and three-output or three-input and two-output circuit. In the operation of single-input and three-output circuit, the lowpass, bandpass and bandreject can be realised simultaneously, while the highpass filtering response can be easily obtained by connecting appropriated output current directly without using addition stages. In the operation of three-input and two-output circuit, all five generic filtering functions can be easily realised by selecting different three input current signals. The filter permits orthogonal controllability of the quality factor and resonance angular frequency, and no component matching conditions or inverting-type input current signals are imposed. All the passive and active sensitivities are low. HSPICE simulation results based on using TSMC 0.18 µm 1P6M CMOS process technology and supply voltages ±0.9 V to verify the theoretical analysis.

  3. A velocity-pressure integrated, mixed interpolation, Galerkin finite element method for high Reynolds number laminar flows

    NASA Technical Reports Server (NTRS)

    Kim, Sang-Wook

    1988-01-01

    A velocity-pressure integrated, mixed interpolation, Galerkin finite element method for the Navier-Stokes equations is presented. In the method, the velocity variables were interpolated using complete quadratic shape functions and the pressure was interpolated using linear shape functions. For the two dimensional case, the pressure is defined on a triangular element which is contained inside the complete biquadratic element for velocity variables; and for the three dimensional case, the pressure is defined on a tetrahedral element which is again contained inside the complete tri-quadratic element. Thus the pressure is discontinuous across the element boundaries. Example problems considered include: a cavity flow for Reynolds number of 400 through 10,000; a laminar backward facing step flow; and a laminar flow in a square duct of strong curvature. The computational results compared favorable with those of the finite difference methods as well as experimental data available. A finite elememt computer program for incompressible, laminar flows is presented.

  4. Coupling of order parameters, chirality, and interfacial structures in multiferroic materials.

    PubMed

    Conti, Sergio; Müller, Stefan; Poliakovsky, Arkady; Salje, Ekhard K H

    2011-04-13

    We study optimal interfacial structures in multiferroic materials with a biquadratic coupling between two order parameters. We discover a new duality relation between the strong coupling and the weak coupling regime for the case of isotropic gradient terms. We analyze the phase diagram depending on the coupling constant and anisotropy of the gradient term, and show that in a certain regime the secondary order parameter becomes activated only in the interfacial region.

  5. The phase diagrams of the ± K model on the Bethe lattice

    NASA Astrophysics Data System (ADS)

    Albayrak, Erhan

    2015-07-01

    The biquadratic exchange interaction is randomized in a bimodal form with probabilities (p) and (1 - p) for the cases with K > 0 (attractive case) and K < 0 (repulsive case), respectively, and its effects on the phase diagrams of the spin-1 Blume-Emery-Griffiths model are studied on the Bethe lattice by using the recursion relations. It was found that the critical behaviors of the model change drastically.

  6. MAGNA (Materially and Geometrically Nonlinear Analysis). Part II. Preprocessor Manual.

    DTIC Science & Technology

    1982-12-01

    AGRID can accept a virtually arbitrary collection of point coor- dinates which lie on a surface of interest, and generate a regular grid of mesh points...in the form of a collection of such patches to be translated into an assemblage of biquadratic surface elements (see Subsection 2.1, Figure 2.2...using IMPRESS can be converted for use with the present preprocessor by means of the IMPRINT translator. IMPRINT is a collection of conversion routines

  7. Origins of giant biquadratic coupling in CoFe/Mn/CoFe sandwich structures (abstract)

    NASA Astrophysics Data System (ADS)

    Koon, Norman C.

    1996-04-01

    Recently Filipkowski et al. reported extremely strong, near 90 degree coupling of 2.5 erg/cm2 for epitaxial sandwiches of CoFe/Mn/CoFe, where the CoFe composition was chosen to be a good lattice match to Mn. Both CoFe and Mn have the bcc structure, but Mn is antiferromagnetic while CoFe is ferromagnetic. It was found that the data were very well described by a simple model due to Slonczewski, in which the interlayer coupling is given by Fc=C+(φ1-φ2)2+C-(φ1-φ2-π)2. While this model describes the data much better than the usual biquadratic form, it still does not connect directly to the microscopic origins of the effect. In the present work we seek to explain the results in terms of normal bilinear exchange and magnetocrystalline anisotropy, together with reasonable assumptions about the structure of the interfaces. We obtain excellent agreement with both the experimental results and the Slonczewski model under the assumptions that at least one of the two CoFe/Mn interfaces is smooth (i.e., atomically flat) on a length scale comparable to or greater than the thickness of the Mn layer and at least one interface is rough on a scale less than approximately a domain wall thickness.

  8. Design of an all-optical fractional-order differentiator with terahertz bandwidth based on a fiber Bragg grating in transmission.

    PubMed

    Liu, Xin; Shu, Xuewen

    2017-08-20

    All-optical fractional-order temporal differentiators with bandwidths reaching terahertz (THz) values are demonstrated with transmissive fiber Bragg gratings. Since the designed fractional-order differentiator is a minimum phase function, the reflective phase of the designed function can be chosen arbitrarily. As examples, we first design several 0.5th-order differentiators with bandwidths reaching the THz range for comparison. The reflective phases of the 0.5th-order differentiators are chosen to be linear phase, quadratic phase, cubic phase, and biquadratic phase, respectively. We find that both the maximum coupling coefficient and the spatial resolution of the designed grating increase when the reflective phase varies from quadratic function to cubic function to biquadratic function. Furthermore, when the reflective phase is chosen to be a quadratic function, the obtained grating coupling coefficient and period are more likely to be achieved in practice. Then we design fractional-order differentiators with different orders when the reflective phase is chosen to be a quadratic function. We see that when the designed order of the differentiator increases, the obtained maximum coupling coefficient also increases while the oscillation of the coupling coefficient decreases. Finally, we give the numerical performance of the designed 0.5th-order differentiator by showing its temporal response and calculating its cross-correlation coefficient.

  9. Peculiarities of stochastic regime of Arctic ice cover time evolution over 1987-2014 from microwave satellite sounding on the basis of NASA team 2 algorithm

    NASA Astrophysics Data System (ADS)

    Raev, M. D.; Sharkov, E. A.; Tikhonov, V. V.; Repina, I. A.; Komarova, N. Yu.

    2015-12-01

    The GLOBAL-RT database (DB) is composed of long-term radio heat multichannel observation data received from DMSP F08-F17 satellites; it is permanently supplemented with new data on the Earth's exploration from the space department of the Space Research Institute, Russian Academy of Sciences. Arctic ice-cover areas for regions higher than 60° N latitude were calculated using the DB polar version and NASA Team 2 algorithm, which is widely used in foreign scientific literature. According to the analysis of variability of Arctic ice cover during 1987-2014, 2 months were selected when the Arctic ice cover was maximal (February) and minimal (September), and the average ice cover area was calculated for these months. Confidence intervals of the average values are in the 95-98% limits. Several approximations are derived for the time dependences of the ice-cover maximum and minimum over the period under study. Regression dependences were calculated for polynomials from the first degree (linear) to sextic. It was ascertained that the minimal root-mean-square error of deviation from the approximated curve sharply decreased for the biquadratic polynomial and then varied insignificantly: from 0.5593 for the polynomial of third degree to 0.4560 for the biquadratic polynomial. Hence, the commonly used strictly linear regression with a negative time gradient for the September Arctic ice cover minimum over 30 years should be considered incorrect.

  10. Assignment Choice, Effort, and Assignment Completion: Does Work Ethic Predict Those Who Choose Higher-Effort Assignments?

    ERIC Educational Resources Information Center

    Parkhurst, John T.; Fleisher, Matthew S.; Skinner, Christopher H.; Woehr, David J.; Hawthorn-Embree, Meredith L.

    2011-01-01

    After completing the Multidimensional Work-Ethic Profile (MWEP), 98 college students were given a 20-problem math computation assignment and instructed to stop working on the assignment after completing 10 problems. Next, they were allowed to choose to finish either the partially completed assignment that had 10 problems remaining or a new…

  11. Thermodynamics of alternate Ising chains of spins 1 and 3/2 with dipolar, biquadratic, and single ion interactions

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

    Fireman, E.C.; dos Santos, R.J.

    1997-04-01

    Within a recently developed extended decoration-transformation formalism we study the thermodynamic properties of a linear chain of alternate Ising {sigma}=1 and S=3/2 spins. We allow for different anisotropy fields on each subchain of different spins. For some range of the parameter space we show the existence of a crossover from a ferromagnetic to an antiferromagnetic-like behavior of the model, as explicitly captured in the susceptibility results. {copyright} {ital 1997 American Institute of Physics.}

  12. Simulated annealing algorithm for solving chambering student-case assignment problem

    NASA Astrophysics Data System (ADS)

    Ghazali, Saadiah; Abdul-Rahman, Syariza

    2015-12-01

    The problem related to project assignment problem is one of popular practical problem that appear nowadays. The challenge of solving the problem raise whenever the complexity related to preferences, the existence of real-world constraints and problem size increased. This study focuses on solving a chambering student-case assignment problem by using a simulated annealing algorithm where this problem is classified under project assignment problem. The project assignment problem is considered as hard combinatorial optimization problem and solving it using a metaheuristic approach is an advantage because it could return a good solution in a reasonable time. The problem of assigning chambering students to cases has never been addressed in the literature before. For the proposed problem, it is essential for law graduates to peruse in chambers before they are qualified to become legal counselor. Thus, assigning the chambering students to cases is a critically needed especially when involving many preferences. Hence, this study presents a preliminary study of the proposed project assignment problem. The objective of the study is to minimize the total completion time for all students in solving the given cases. This study employed a minimum cost greedy heuristic in order to construct a feasible initial solution. The search then is preceded with a simulated annealing algorithm for further improvement of solution quality. The analysis of the obtained result has shown that the proposed simulated annealing algorithm has greatly improved the solution constructed by the minimum cost greedy heuristic. Hence, this research has demonstrated the advantages of solving project assignment problem by using metaheuristic techniques.

  13. Unifying Temporal and Structural Credit Assignment Problems

    NASA Technical Reports Server (NTRS)

    Agogino, Adrian K.; Tumer, Kagan

    2004-01-01

    Single-agent reinforcement learners in time-extended domains and multi-agent systems share a common dilemma known as the credit assignment problem. Multi-agent systems have the structural credit assignment problem of determining the contributions of a particular agent to a common task. Instead, time-extended single-agent systems have the temporal credit assignment problem of determining the contribution of a particular action to the quality of the full sequence of actions. Traditionally these two problems are considered different and are handled in separate ways. In this article we show how these two forms of the credit assignment problem are equivalent. In this unified frame-work, a single-agent Markov decision process can be broken down into a single-time-step multi-agent process. Furthermore we show that Monte-Carlo estimation or Q-learning (depending on whether the values of resulting actions in the episode are known at the time of learning) are equivalent to different agent utility functions in a multi-agent system. This equivalence shows how an often neglected issue in multi-agent systems is equivalent to a well-known deficiency in multi-time-step learning and lays the basis for solving time-extended multi-agent problems, where both credit assignment problems are present.

  14. A Scenario-Based Parametric Analysis of Stable Marriage Approaches to the Army Officer Assignment Problem

    DTIC Science & Technology

    2017-03-23

    solutions obtained through their proposed method to comparative instances of a generalized assignment problem with either ordinal cost components or... method flag: Designates the method by which the changed/ new assignment problem instance is solved. methodFlag = 0:SMAWarmstart Returns a matching...of randomized perturbations. We examine the contrasts between these methods in the context of assigning Army Officers among a set of identified

  15. Optimal processor assignment for pipeline computations

    NASA Technical Reports Server (NTRS)

    Nicol, David M.; Simha, Rahul; Choudhury, Alok N.; Narahari, Bhagirath

    1991-01-01

    The availability of large scale multitasked parallel architectures introduces the following processor assignment problem for pipelined computations. Given a set of tasks and their precedence constraints, along with their experimentally determined individual responses times for different processor sizes, find an assignment of processor to tasks. Two objectives are of interest: minimal response given a throughput requirement, and maximal throughput given a response time requirement. These assignment problems differ considerably from the classical mapping problem in which several tasks share a processor; instead, it is assumed that a large number of processors are to be assigned to a relatively small number of tasks. Efficient assignment algorithms were developed for different classes of task structures. For a p processor system and a series parallel precedence graph with n constituent tasks, an O(np2) algorithm is provided that finds the optimal assignment for the response time optimization problem; it was found that the assignment optimizing the constrained throughput in O(np2log p) time. Special cases of linear, independent, and tree graphs are also considered.

  16. A Multiple Ant Colony Metahuristic for the Air Refueling Tanker Assignment Problem

    DTIC Science & Technology

    2002-03-01

    Problem The tanker assignment problem can be modeled as a job shop scheduling problem ( JSSP ). The JSSP is made up of n jobs, composed of m ordered...points) to be processed on all the machines (tankers). The problem with using JSSP is that the tanker assignment problem has multiple objectives... JSSP will minimize the time it takes for all jobs, but this may take an inordinate number of tankers. Thus using JSSP alone is not necessarily a good

  17. Achieving spectrum conservation for the minimum-span and minimum-order frequency assignment problems

    NASA Technical Reports Server (NTRS)

    Heyward, Ann O.

    1992-01-01

    Effective and efficient solutions of frequency assignment problems assumes increasing importance as the radiofrequency spectrum experiences ever increasing utilization by diverse communications services, requiring that the most efficient use of this resource be achieved. The research presented explores a general approach to the frequency assignment problem, in which such problems are categorized by the appropriate spectrum conserving objective function, and are each treated as an N-job, M-machine scheduling problem appropriate for the objective. Results obtained and presented illustrate that such an approach presents an effective means of achieving spectrum conserving frequency assignments for communications systems in a variety of environments.

  18. Integer Linear Programming for Constrained Multi-Aspect Committee Review Assignment

    PubMed Central

    Karimzadehgan, Maryam; Zhai, ChengXiang

    2011-01-01

    Automatic review assignment can significantly improve the productivity of many people such as conference organizers, journal editors and grant administrators. A general setup of the review assignment problem involves assigning a set of reviewers on a committee to a set of documents to be reviewed under the constraint of review quota so that the reviewers assigned to a document can collectively cover multiple topic aspects of the document. No previous work has addressed such a setup of committee review assignments while also considering matching multiple aspects of topics and expertise. In this paper, we tackle the problem of committee review assignment with multi-aspect expertise matching by casting it as an integer linear programming problem. The proposed algorithm can naturally accommodate any probabilistic or deterministic method for modeling multiple aspects to automate committee review assignments. Evaluation using a multi-aspect review assignment test set constructed using ACM SIGIR publications shows that the proposed algorithm is effective and efficient for committee review assignments based on multi-aspect expertise matching. PMID:22711970

  19. An Efficacy Study of Interleaved Mathematics Practice. Revised

    ERIC Educational Resources Information Center

    Rohrer, Doug; Dedrick, Robert F.; Burgess, Kaleena

    2013-01-01

    In a typical mathematics course, the material is divided into many lessons, and each lesson is followed by an assignment consisting of practice problems. Most commonly, each assignment consists solely of problems on the preceding lesson. For example, a lesson on ratios might be followed by an assignment with 12 problems on ratios. In other words,…

  20. Single Machine Scheduling and Due Date Assignment with Past-Sequence-Dependent Setup Time and Position-Dependent Processing Time

    PubMed Central

    Zhao, Chuan-Li; Hsu, Hua-Feng

    2014-01-01

    This paper considers single machine scheduling and due date assignment with setup time. The setup time is proportional to the length of the already processed jobs; that is, the setup time is past-sequence-dependent (p-s-d). It is assumed that a job's processing time depends on its position in a sequence. The objective functions include total earliness, the weighted number of tardy jobs, and the cost of due date assignment. We analyze these problems with two different due date assignment methods. We first consider the model with job-dependent position effects. For each case, by converting the problem to a series of assignment problems, we proved that the problems can be solved in O(n 4) time. For the model with job-independent position effects, we proved that the problems can be solved in O(n 3) time by providing a dynamic programming algorithm. PMID:25258727

  1. Single machine scheduling and due date assignment with past-sequence-dependent setup time and position-dependent processing time.

    PubMed

    Zhao, Chuan-Li; Hsu, Chou-Jung; Hsu, Hua-Feng

    2014-01-01

    This paper considers single machine scheduling and due date assignment with setup time. The setup time is proportional to the length of the already processed jobs; that is, the setup time is past-sequence-dependent (p-s-d). It is assumed that a job's processing time depends on its position in a sequence. The objective functions include total earliness, the weighted number of tardy jobs, and the cost of due date assignment. We analyze these problems with two different due date assignment methods. We first consider the model with job-dependent position effects. For each case, by converting the problem to a series of assignment problems, we proved that the problems can be solved in O(n(4)) time. For the model with job-independent position effects, we proved that the problems can be solved in O(n(3)) time by providing a dynamic programming algorithm.

  2. QUICR-learning for Multi-Agent Coordination

    NASA Technical Reports Server (NTRS)

    Agogino, Adrian K.; Tumer, Kagan

    2006-01-01

    Coordinating multiple agents that need to perform a sequence of actions to maximize a system level reward requires solving two distinct credit assignment problems. First, credit must be assigned for an action taken at time step t that results in a reward at time step t > t. Second, credit must be assigned for the contribution of agent i to the overall system performance. The first credit assignment problem is typically addressed with temporal difference methods such as Q-learning. The second credit assignment problem is typically addressed by creating custom reward functions. To address both credit assignment problems simultaneously, we propose the "Q Updates with Immediate Counterfactual Rewards-learning" (QUICR-learning) designed to improve both the convergence properties and performance of Q-learning in large multi-agent problems. QUICR-learning is based on previous work on single-time-step counterfactual rewards described by the collectives framework. Results on a traffic congestion problem shows that QUICR-learning is significantly better than a Q-learner using collectives-based (single-time-step counterfactual) rewards. In addition QUICR-learning provides significant gains over conventional and local Q-learning. Additional results on a multi-agent grid-world problem show that the improvements due to QUICR-learning are not domain specific and can provide up to a ten fold increase in performance over existing methods.

  3. A Parallel Biological Optimization Algorithm to Solve the Unbalanced Assignment Problem Based on DNA Molecular Computing.

    PubMed

    Wang, Zhaocai; Pu, Jun; Cao, Liling; Tan, Jian

    2015-10-23

    The unbalanced assignment problem (UAP) is to optimally resolve the problem of assigning n jobs to m individuals (m < n), such that minimum cost or maximum profit obtained. It is a vitally important Non-deterministic Polynomial (NP) complete problem in operation management and applied mathematics, having numerous real life applications. In this paper, we present a new parallel DNA algorithm for solving the unbalanced assignment problem using DNA molecular operations. We reasonably design flexible-length DNA strands representing different jobs and individuals, take appropriate steps, and get the solutions of the UAP in the proper length range and O(mn) time. We extend the application of DNA molecular operations and simultaneity to simplify the complexity of the computation.

  4. Measuring Conceptual Gains and Benefits of Student Problem Designs

    NASA Astrophysics Data System (ADS)

    Mandell, Eric; Snyder, Rachel; Oswald, Wayne

    2011-10-01

    Writing assignments can be an effective way of getting students to practice higher-order learning skills in physics. One example of such an assignment is that of problem design. One version of the problem design assignment asks the student to evaluate the material from a chapter, after all instruction and other activities are complete. The student is to decide what concepts and ideas are most central, or critical in the chapter, and construct a problem that he or she feels best encompasses the major themes. Here, we use two concept surveys (FCI and EMCS) to measure conceptual gains for students completing the problem design assignment and present the preliminary results, comparing across several categories including gender, age, degree program, and class standing.

  5. The airport gate assignment problem: a survey.

    PubMed

    Bouras, Abdelghani; Ghaleb, Mageed A; Suryahatmaja, Umar S; Salem, Ahmed M

    2014-01-01

    The airport gate assignment problem (AGAP) is one of the most important problems operations managers face daily. Many researches have been done to solve this problem and tackle its complexity. The objective of the task is assigning each flight (aircraft) to an available gate while maximizing both conveniences to passengers and the operational efficiency of airport. This objective requires a solution that provides the ability to change and update the gate assignment data on a real time basis. In this paper, we survey the state of the art of these problems and the various methods to obtain the solution. Our survey covers both theoretical and real AGAP with the description of mathematical formulations and resolution methods such as exact algorithms, heuristic algorithms, and metaheuristic algorithms. We also provide a research trend that can inspire researchers about new problems in this area.

  6. The Airport Gate Assignment Problem: A Survey

    PubMed Central

    Ghaleb, Mageed A.; Salem, Ahmed M.

    2014-01-01

    The airport gate assignment problem (AGAP) is one of the most important problems operations managers face daily. Many researches have been done to solve this problem and tackle its complexity. The objective of the task is assigning each flight (aircraft) to an available gate while maximizing both conveniences to passengers and the operational efficiency of airport. This objective requires a solution that provides the ability to change and update the gate assignment data on a real time basis. In this paper, we survey the state of the art of these problems and the various methods to obtain the solution. Our survey covers both theoretical and real AGAP with the description of mathematical formulations and resolution methods such as exact algorithms, heuristic algorithms, and metaheuristic algorithms. We also provide a research trend that can inspire researchers about new problems in this area. PMID:25506074

  7. A Parallel Biological Optimization Algorithm to Solve the Unbalanced Assignment Problem Based on DNA Molecular Computing

    PubMed Central

    Wang, Zhaocai; Pu, Jun; Cao, Liling; Tan, Jian

    2015-01-01

    The unbalanced assignment problem (UAP) is to optimally resolve the problem of assigning n jobs to m individuals (m < n), such that minimum cost or maximum profit obtained. It is a vitally important Non-deterministic Polynomial (NP) complete problem in operation management and applied mathematics, having numerous real life applications. In this paper, we present a new parallel DNA algorithm for solving the unbalanced assignment problem using DNA molecular operations. We reasonably design flexible-length DNA strands representing different jobs and individuals, take appropriate steps, and get the solutions of the UAP in the proper length range and O(mn) time. We extend the application of DNA molecular operations and simultaneity to simplify the complexity of the computation. PMID:26512650

  8. Measurement-based quantum teleportation on finite AKLT chains

    NASA Astrophysics Data System (ADS)

    Fujii, Akihiko; Feder, David

    In the measurement-based model of quantum computation, universal quantum operations are effected by making repeated local measurements on resource states which contain suitable entanglement. Resource states include two-dimensional cluster states and the ground state of the Affleck-Kennedy-Lieb-Tasaki (AKLT) state on the honeycomb lattice. Recent studies suggest that measurements on one-dimensional systems in the Haldane phase teleport perfect single-qubit gates in the correlation space, protected by the underlying symmetry. As laboratory realizations of symmetry-protected states will necessarily be finite, we investigate the potential for quantum gate teleportation in finite chains of a bilinear-biquadratic Hamiltonian which is a generalization of the AKLT model representing the full Haldane phase.

  9. Mechanism of interlayer exchange in magnetic multilayers

    NASA Astrophysics Data System (ADS)

    Slonczewski, J. C.

    1993-09-01

    The spin-current method is used to calculate the oscillatory exchange energy that couples two semi-infinite ferromagnets with exchange-split parabolic bands which are joined by a nonmagnetic metallic spacer. A closed asymptotic formula extends the previous RKKY-type formula to the case in which the ferromagnets and spacer have different Fermi vectors. The predicted amplitude of oscillatory coupling increases steeply with Fermi vector or electron density in the spacer, as do the experimental trends reported by Parkin. Numerical computations relevant to iron support this closed formula and show that the amplitude of the biquadratic ( J2 cos 2θ) and higher-order corrections to the conventional - J1 cos θ form of energy is less than 2%.

  10. Decision Making In Assignment Problem With Multiple Attributes Under Intuitionistic Fuzzy Environment

    NASA Astrophysics Data System (ADS)

    Mukherjee, Sathi; Basu, Kajla

    2010-10-01

    In this paper we develop a methodology to solve the multiple attribute assignment problems where the attributes are considered to be Intuitionistic Fuzzy Sets (IFS). We apply the concept of similarity measures of IFS to solve the Intuitionistic Fuzzy Multi-Attribute Assignment Problem (IFMAAP). The weights of the attributes are determined from expert opinion. An illustrative example is solved to verify the developed approach and to demonstrate its practicality.

  11. Evaluation of a Brief Homework Assignment Designed to Reduce Citation Problems

    ERIC Educational Resources Information Center

    Schuetze, Pamela

    2004-01-01

    I evaluated a brief homework assignment designed to reduce citation problems in research-based term papers. Students in 2 developmental psychology classes received a brief presentation and handout defining plagiarism with tips on how to cite sources to avoid plagiarizing. In addition, students in 1 class completed 2 brief homework assignments in…

  12. Absolute Points for Multiple Assignment Problems

    ERIC Educational Resources Information Center

    Adlakha, V.; Kowalski, K.

    2006-01-01

    An algorithm is presented to solve multiple assignment problems in which a cost is incurred only when an assignment is made at a given cell. The proposed method recursively searches for single/group absolute points to identify cells that must be loaded in any optimal solution. Unlike other methods, the first solution is the optimal solution. The…

  13. Computing Role Assignments of Proper Interval Graphs in Polynomial Time

    NASA Astrophysics Data System (ADS)

    Heggernes, Pinar; van't Hof, Pim; Paulusma, Daniël

    A homomorphism from a graph G to a graph R is locally surjective if its restriction to the neighborhood of each vertex of G is surjective. Such a homomorphism is also called an R-role assignment of G. Role assignments have applications in distributed computing, social network theory, and topological graph theory. The Role Assignment problem has as input a pair of graphs (G,R) and asks whether G has an R-role assignment. This problem is NP-complete already on input pairs (G,R) where R is a path on three vertices. So far, the only known non-trivial tractable case consists of input pairs (G,R) where G is a tree. We present a polynomial time algorithm that solves Role Assignment on all input pairs (G,R) where G is a proper interval graph. Thus we identify the first graph class other than trees on which the problem is tractable. As a complementary result, we show that the problem is Graph Isomorphism-hard on chordal graphs, a superclass of proper interval graphs and trees.

  14. Web-Based Problem-Solving Assignment and Grading System

    NASA Astrophysics Data System (ADS)

    Brereton, Giles; Rosenberg, Ronald

    2014-11-01

    In engineering courses with very specific learning objectives, such as fluid mechanics and thermodynamics, it is conventional to reinforce concepts and principles with problem-solving assignments and to measure success in problem solving as an indicator of student achievement. While the modern-day ease of copying and searching for online solutions can undermine the value of traditional assignments, web-based technologies also provide opportunities to generate individualized well-posed problems with an infinite number of different combinations of initial/final/boundary conditions, so that the probability of any two students being assigned identical problems in a course is vanishingly small. Such problems can be designed and programmed to be: single or multiple-step, self-grading, allow students single or multiple attempts; provide feedback when incorrect; selectable according to difficulty; incorporated within gaming packages; etc. In this talk, we discuss the use of a homework/exam generating program of this kind in a single-semester course, within a web-based client-server system that ensures secure operation.

  15. Advanced optimal design concepts for composite material aircraft repair

    NASA Astrophysics Data System (ADS)

    Renaud, Guillaume

    The application of an automated optimization approach for bonded composite patch design is investigated. To do so, a finite element computer analysis tool to evaluate patch design quality was developed. This tool examines both the mechanical and the thermal issues of the problem. The optimized shape is obtained with a bi-quadratic B-spline surface that represents the top surface of the patch. Additional design variables corresponding to the ply angles are also used. Furthermore, a multi-objective optimization approach was developed to treat multiple and uncertain loads. This formulation aims at designing according to the most unfavorable mechanical and thermal loads. The problem of finding the optimal patch shape for several situations is addressed. The objective is to minimize a stress component at a specific point in the host structure (plate) while ensuring acceptable stress levels in the adhesive. A parametric study is performed in order to identify the effects of various shape parameters on the quality of the repair and its optimal configuration. The effects of mechanical loads and service temperature are also investigated. Two bonding methods are considered, as they imply different thermal histories. It is shown that the proposed techniques are effective and inexpensive for analyzing and optimizing composite patch repairs. It is also shown that thermal effects should not only be present in the analysis, but that they play a paramount role on the resulting quality of the optimized design. In all cases, the optimized configuration results in a significant reduction of the desired stress level by deflecting the loads away from rather than over the damage zone, as is the case with standard designs. Furthermore, the automated optimization ensures the safety of the patch design for all considered operating conditions.

  16. Matrix product states for su(2) invariant quantum spin chains

    NASA Astrophysics Data System (ADS)

    Zadourian, Rubina; Fledderjohann, Andreas; Klümper, Andreas

    2016-08-01

    A systematic and compact treatment of arbitrary su(2) invariant spin-s quantum chains with nearest-neighbour interactions is presented. The ground-state is derived in terms of matrix product states (MPS). The fundamental MPS calculations consist of taking products of basic tensors of rank 3 and contractions thereof. The algebraic su(2) calculations are carried out completely by making use of Wigner calculus. As an example of application, the spin-1 bilinear-biquadratic quantum chain is investigated. Various physical quantities are calculated with high numerical accuracy of up to 8 digits. We obtain explicit results for the ground-state energy, entanglement entropy, singlet operator correlations and the string order parameter. We find an interesting crossover phenomenon in the correlation lengths.

  17. Full thermomechanical coupling in modelling of micropolar thermoelasticity

    NASA Astrophysics Data System (ADS)

    Murashkin, E. V.; Radayev, Y. N.

    2018-04-01

    The present paper is devoted to plane harmonic waves of displacements and microrotations propagating in fully coupled thermoelastic continua. The analysis is carried out in the framework of linear conventional thermoelastic micropolar continuum model. The reduced energy balance equation and the special form of the Helmholtz free energy are discussed. The constitutive constants providing fully coupling of equations of motion and heat conduction are considered. The dispersion equation is derived and analysed in the form bi-cubic and bi-quadratic polynoms product. The equation are analyzed by the computer algebra system Mathematica. Algebraic forms expressed by complex multivalued square and cubic radicals are obtained for wavenumbers of transverse and longitudinal waves. The exact forms of wavenumbers of a plane harmonic coupled thermoelastic waves are computed.

  18. Single-machine common/slack due window assignment problems with linear decreasing processing times

    NASA Astrophysics Data System (ADS)

    Zhang, Xingong; Lin, Win-Chin; Wu, Wen-Hsiang; Wu, Chin-Chia

    2017-08-01

    This paper studies linear non-increasing processing times and the common/slack due window assignment problems on a single machine, where the actual processing time of a job is a linear non-increasing function of its starting time. The aim is to minimize the sum of the earliness cost, tardiness cost, due window location and due window size. Some optimality results are discussed for the common/slack due window assignment problems and two O(n log n) time algorithms are presented to solve the two problems. Finally, two examples are provided to illustrate the correctness of the corresponding algorithms.

  19. Learning graph matching.

    PubMed

    Caetano, Tibério S; McAuley, Julian J; Cheng, Li; Le, Quoc V; Smola, Alex J

    2009-06-01

    As a fundamental problem in pattern recognition, graph matching has applications in a variety of fields, from computer vision to computational biology. In graph matching, patterns are modeled as graphs and pattern recognition amounts to finding a correspondence between the nodes of different graphs. Many formulations of this problem can be cast in general as a quadratic assignment problem, where a linear term in the objective function encodes node compatibility and a quadratic term encodes edge compatibility. The main research focus in this theme is about designing efficient algorithms for approximately solving the quadratic assignment problem, since it is NP-hard. In this paper we turn our attention to a different question: how to estimate compatibility functions such that the solution of the resulting graph matching problem best matches the expected solution that a human would manually provide. We present a method for learning graph matching: the training examples are pairs of graphs and the 'labels' are matches between them. Our experimental results reveal that learning can substantially improve the performance of standard graph matching algorithms. In particular, we find that simple linear assignment with such a learning scheme outperforms Graduated Assignment with bistochastic normalisation, a state-of-the-art quadratic assignment relaxation algorithm.

  20. More reliable protein NMR peak assignment via improved 2-interval scheduling.

    PubMed

    Chen, Zhi-Zhong; Lin, Guohui; Rizzi, Romeo; Wen, Jianjun; Xu, Dong; Xu, Ying; Jiang, Tao

    2005-03-01

    Protein NMR peak assignment refers to the process of assigning a group of "spin systems" obtained experimentally to a protein sequence of amino acids. The automation of this process is still an unsolved and challenging problem in NMR protein structure determination. Recently, protein NMR peak assignment has been formulated as an interval scheduling problem (ISP), where a protein sequence P of amino acids is viewed as a discrete time interval I (the amino acids on P one-to-one correspond to the time units of I), each subset S of spin systems that are known to originate from consecutive amino acids from P is viewed as a "job" j(s), the preference of assigning S to a subsequence P of consecutive amino acids on P is viewed as the profit of executing job j(s) in the subinterval of I corresponding to P, and the goal is to maximize the total profit of executing the jobs (on a single machine) during I. The interval scheduling problem is max SNP-hard in general; but in the real practice of protein NMR peak assignment, each job j(s) usually requires at most 10 consecutive time units, and typically the jobs that require one or two consecutive time units are the most difficult to assign/schedule. In order to solve these most difficult assignments, we present an efficient 13/7-approximation algorithm for the special case of the interval scheduling problem where each job takes one or two consecutive time units. Combining this algorithm with a greedy filtering strategy for handling long jobs (i.e., jobs that need more than two consecutive time units), we obtain a new efficient heuristic for protein NMR peak assignment. Our experimental study shows that the new heuristic produces the best peak assignment in most of the cases, compared with the NMR peak assignment algorithms in the recent literature. The above algorithm is also the first approximation algorithm for a nontrivial case of the well-known interval scheduling problem that breaks the ratio 2 barrier.

  1. Single machine scheduling with slack due dates assignment

    NASA Astrophysics Data System (ADS)

    Liu, Weiguo; Hu, Xiangpei; Wang, Xuyin

    2017-04-01

    This paper considers a single machine scheduling problem in which each job is assigned an individual due date based on a common flow allowance (i.e. all jobs have slack due date). The goal is to find a sequence for jobs, together with a due date assignment, that minimizes a non-regular criterion comprising the total weighted absolute lateness value and common flow allowance cost, where the weight is a position-dependent weight. In order to solve this problem, an ? time algorithm is proposed. Some extensions of the problem are also shown.

  2. A Stochastic Employment Problem

    ERIC Educational Resources Information Center

    Wu, Teng

    2013-01-01

    The Stochastic Employment Problem(SEP) is a variation of the Stochastic Assignment Problem which analyzes the scenario that one assigns balls into boxes. Balls arrive sequentially with each one having a binary vector X = (X[subscript 1], X[subscript 2],...,X[subscript n]) attached, with the interpretation being that if X[subscript i] = 1 the ball…

  3. A General Chemistry Assignment Analyzing Environmental Contamination for the Depue, IL, National Superfund Site

    ERIC Educational Resources Information Center

    Saslow Gomez, Sarah A.; Faurie-Wisniewski, Danielle; Parsa, Arlen; Spitz, Jeff; Spitz, Jennifer Amdur; Loeb, Nancy C.; Geiger, Franz M.

    2015-01-01

    The classroom exercise outlined here is a self-directed assignment that connects students to the environmental contamination problem surrounding the DePue Superfund site. By connecting chemistry knowledge gained in the classroom with a real-world problem, students are encouraged to personally connect with the problem while simultaneously…

  4. Pre-service teachers’ challenges in presenting mathematical problems

    NASA Astrophysics Data System (ADS)

    Desfitri, R.

    2018-01-01

    The purpose of this study was to analyzed how pre-service teachers prepare and assigned tasks or assignments in teaching practice situations. This study was also intended to discuss about kind of tasks or assignments they gave to students. Participants of this study were 15 selected pre-service mathematics teachers from mathematics education department who took part on microteaching class as part of teaching preparation program. Based on data obtained, it was occasionally found that there were hidden errors on questions or tasks assigned by pre-service teachers which might lead their students not to be able to reach a logical or correct answer. Although some answers might seem to be true, they were illogical or unfavourable. It is strongly recommended that pre-service teachers be more careful when posing mathematical problems so that students do not misunderstand the problems or the concepts, since both teachers and students were sometimes unaware of errors in problems being worked on.

  5. New optimization model for routing and spectrum assignment with nodes insecurity

    NASA Astrophysics Data System (ADS)

    Xuan, Hejun; Wang, Yuping; Xu, Zhanqi; Hao, Shanshan; Wang, Xiaoli

    2017-04-01

    By adopting the orthogonal frequency division multiplexing technology, elastic optical networks can provide the flexible and variable bandwidth allocation to each connection request and get higher spectrum utilization. The routing and spectrum assignment problem in elastic optical network is a well-known NP-hard problem. In addition, information security has received worldwide attention. We combine these two problems to investigate the routing and spectrum assignment problem with the guaranteed security in elastic optical network, and establish a new optimization model to minimize the maximum index of the used frequency slots, which is used to determine an optimal routing and spectrum assignment schemes. To solve the model effectively, a hybrid genetic algorithm framework integrating a heuristic algorithm into a genetic algorithm is proposed. The heuristic algorithm is first used to sort the connection requests and then the genetic algorithm is designed to look for an optimal routing and spectrum assignment scheme. In the genetic algorithm, tailor-made crossover, mutation and local search operators are designed. Moreover, simulation experiments are conducted with three heuristic strategies, and the experimental results indicate that the effectiveness of the proposed model and algorithm framework.

  6. Problem-Based Assignments as a Trigger for Developing Ethical and Reflective Competencies

    ERIC Educational Resources Information Center

    Euler, Dieter; Kühner, Patrizia

    2017-01-01

    The following research question serves as the starting point of this research and development project: How, in the context of a didactic design, can problem-based assignments trigger learning activities for the development of ethical and reflective competencies in students in economics courses? This paper focuses on the design of problem-based…

  7. Investigation of the Effect of Assignment Projects on Mathematical Activity of Graduating Junior High School Students.

    ERIC Educational Resources Information Center

    Zehavi, Nurit

    This study explored student mathematical activity in open problem-solving situations, derived from the work of Polya on problem solving and Skemp on intelligent learning and teaching. Assignment projects with problems for ninth-grade students were developed, whether they elicit the desired cognitive and cogno-affective goals was investigated, and…

  8. Ant colony optimization for solving university facility layout problem

    NASA Astrophysics Data System (ADS)

    Mohd Jani, Nurul Hafiza; Mohd Radzi, Nor Haizan; Ngadiman, Mohd Salihin

    2013-04-01

    Quadratic Assignment Problems (QAP) is classified as the NP hard problem. It has been used to model a lot of problem in several areas such as operational research, combinatorial data analysis and also parallel and distributed computing, optimization problem such as graph portioning and Travel Salesman Problem (TSP). In the literature, researcher use exact algorithm, heuristics algorithm and metaheuristic approaches to solve QAP problem. QAP is largely applied in facility layout problem (FLP). In this paper we used QAP to model university facility layout problem. There are 8 facilities that need to be assigned to 8 locations. Hence we have modeled a QAP problem with n ≤ 10 and developed an Ant Colony Optimization (ACO) algorithm to solve the university facility layout problem. The objective is to assign n facilities to n locations such that the minimum product of flows and distances is obtained. Flow is the movement from one to another facility, whereas distance is the distance between one locations of a facility to other facilities locations. The objective of the QAP is to obtain minimum total walking (flow) of lecturers from one destination to another (distance).

  9. Comparing Looping Teacher-Assigned and Traditional Teacher-Assigned Student Achievement Scores

    ERIC Educational Resources Information Center

    Lloyd, Melissa C.

    2014-01-01

    A problem in many elementary schools is determining which teacher assignment strategy best promotes the academic progress of students. To find and implement educational practices that address the academic needs of all learners, schools need research-based data focusing on the 2 teacher assignment strategies: looping assignment (LA) and traditional…

  10. Solution of the Lindblad equation for spin helix states.

    PubMed

    Popkov, V; Schütz, G M

    2017-04-01

    Using Lindblad dynamics we study quantum spin systems with dissipative boundary dynamics that generate a stationary nonequilibrium state with a nonvanishing spin current that is locally conserved except at the boundaries. We demonstrate that with suitably chosen boundary target states one can solve the many-body Lindblad equation exactly in any dimension. As solution we obtain pure states at any finite value of the dissipation strength and any system size. They are characterized by a helical stationary magnetization profile and a ballistic spin current which is independent of system size, even when the quantum spin system is not integrable. These results are derived in explicit form for the one-dimensional spin-1/2 Heisenberg chain and its higher-spin generalizations, which include the integrable spin-1 Zamolodchikov-Fateev model and the biquadratic Heisenberg chain.

  11. Parameterized Complexity Results for General Factors in Bipartite Graphs with an Application to Constraint Programming

    NASA Astrophysics Data System (ADS)

    Gutin, Gregory; Kim, Eun Jung; Soleimanfallah, Arezou; Szeider, Stefan; Yeo, Anders

    The NP-hard general factor problem asks, given a graph and for each vertex a list of integers, whether the graph has a spanning subgraph where each vertex has a degree that belongs to its assigned list. The problem remains NP-hard even if the given graph is bipartite with partition U ⊎ V, and each vertex in U is assigned the list {1}; this subproblem appears in the context of constraint programming as the consistency problem for the extended global cardinality constraint. We show that this subproblem is fixed-parameter tractable when parameterized by the size of the second partite set V. More generally, we show that the general factor problem for bipartite graphs, parameterized by |V |, is fixed-parameter tractable as long as all vertices in U are assigned lists of length 1, but becomes W[1]-hard if vertices in U are assigned lists of length at most 2. We establish fixed-parameter tractability by reducing the problem instance to a bounded number of acyclic instances, each of which can be solved in polynomial time by dynamic programming.

  12. Quicker Q-Learning in Multi-Agent Systems

    NASA Technical Reports Server (NTRS)

    Agogino, Adrian K.; Tumer, Kagan

    2005-01-01

    Multi-agent learning in Markov Decisions Problems is challenging because of the presence ot two credit assignment problems: 1) How to credit an action taken at time step t for rewards received at t' greater than t; and 2) How to credit an action taken by agent i considering the system reward is a function of the actions of all the agents. The first credit assignment problem is typically addressed with temporal difference methods such as Q-learning OK TD(lambda) The second credit assi,onment problem is typically addressed either by hand-crafting reward functions that assign proper credit to an agent, or by making certain independence assumptions about an agent's state-space and reward function. To address both credit assignment problems simultaneously, we propose the Q Updates with Immediate Counterfactual Rewards-learning (QUICR-learning) designed to improve both the convergence properties and performance of Q-learning in large multi-agent problems. Instead of assuming that an agent s value function can be made independent of other agents, this method suppresses the impact of other agents using counterfactual rewards. Results on multi-agent grid-world problems over multiple topologies show that QUICR-learning can achieve up to thirty fold improvements in performance over both conventional and local Q-learning in the largest tested systems.

  13. Meta-cognitive student reflections

    NASA Astrophysics Data System (ADS)

    Barquist, Britt; Stewart, Jim

    2009-05-01

    We have recently concluded a project testing the effectiveness of a weekly assignment designed to encourage awareness and improvement of meta-cognitive skills. The project is based on the idea that successful problem solvers implement a meta-cognitive process in which they identify the specific concept they are struggling with, and then identify what they understand, what they don't understand, and what they need to know in order to resolve their problem. The assignment required the students to write an email assessing the level of completion of a weekly workbook assignment and to examine in detail their experiences regarding a specific topic they struggled with. The assignment guidelines were designed to coach them through this meta-cognitive process. We responded to most emails with advice for next week's assignment. Our data follow 12 students through a quarter consisting of 11 email assignments which were scored using a rubric based on the assignment guidelines. We found no correlation between rubric scores and final grades. We do have anecdotal evidence that the assignment was beneficial.

  14. Determining the relationship between students' scores using traditional homework assignments to those who used assignments on a non-traditional interactive CD with tutor helps

    NASA Astrophysics Data System (ADS)

    Tinney, Charles Evan

    2007-12-01

    By using the book "Physics for Scientists and Engineers" by Raymond A. Serway as a guide, CD problem sets for teaching a calculus-based physics course were developed, programmed, and evaluated for homework assignments during the 2003-2004 academic year at Utah State University. These CD sets were used to replace the traditionally handwritten and submitted homework sets. They included a research-based format that guided the students through problem-solving techniques using responseactivated helps and suggestions. The CD contents were designed to help the student improve his/her physics problem-solving skills. The analyzed score results showed a direct correlation between the scores obtained on the homework and the students' time spent per problem, as well as the number of helps used per problem.

  15. Ontological Problem-Solving Framework for Assigning Sensor Systems and Algorithms to High-Level Missions

    PubMed Central

    Qualls, Joseph; Russomanno, David J.

    2011-01-01

    The lack of knowledge models to represent sensor systems, algorithms, and missions makes opportunistically discovering a synthesis of systems and algorithms that can satisfy high-level mission specifications impractical. A novel ontological problem-solving framework has been designed that leverages knowledge models describing sensors, algorithms, and high-level missions to facilitate automated inference of assigning systems to subtasks that may satisfy a given mission specification. To demonstrate the efficacy of the ontological problem-solving architecture, a family of persistence surveillance sensor systems and algorithms has been instantiated in a prototype environment to demonstrate the assignment of systems to subtasks of high-level missions. PMID:22164081

  16. Generalised Assignment Matrix Methodology in Linear Programming

    ERIC Educational Resources Information Center

    Jerome, Lawrence

    2012-01-01

    Discrete Mathematics instructors and students have long been struggling with various labelling and scanning algorithms for solving many important problems. This paper shows how to solve a wide variety of Discrete Mathematics and OR problems using assignment matrices and linear programming, specifically using Excel Solvers although the same…

  17. Topological numbering of features on a mesh

    NASA Technical Reports Server (NTRS)

    Atallah, Mikhail J.; Hambrusch, Susanne E.; Tewinkel, Lynn E.

    1988-01-01

    Assume a nxn binary image is given containing horizontally convex features; i.e., for each feature, each of its row's pixels form an interval on that row. The problem of assigning topological numbers to such features is considered; i.e., assign a number to every feature f so that all features to the left of f have a smaller number assigned to them. This problem arises in solutions to the stereo matching problem. A parallel algorithm to solve the topological numbering problem in O(n) time on an nxn mesh of processors is presented. The key idea of the solution is to create a tree from which the topological numbers can be obtained even though the tree does not uniquely represent the to the left of relationship of the features.

  18. Optimizing a realistic large-scale frequency assignment problem using a new parallel evolutionary approach

    NASA Astrophysics Data System (ADS)

    Chaves-González, José M.; Vega-Rodríguez, Miguel A.; Gómez-Pulido, Juan A.; Sánchez-Pérez, Juan M.

    2011-08-01

    This article analyses the use of a novel parallel evolutionary strategy to solve complex optimization problems. The work developed here has been focused on a relevant real-world problem from the telecommunication domain to verify the effectiveness of the approach. The problem, known as frequency assignment problem (FAP), basically consists of assigning a very small number of frequencies to a very large set of transceivers used in a cellular phone network. Real data FAP instances are very difficult to solve due to the NP-hard nature of the problem, therefore using an efficient parallel approach which makes the most of different evolutionary strategies can be considered as a good way to obtain high-quality solutions in short periods of time. Specifically, a parallel hyper-heuristic based on several meta-heuristics has been developed. After a complete experimental evaluation, results prove that the proposed approach obtains very high-quality solutions for the FAP and beats any other result published.

  19. Task Assignment and Path Planning for Multiple Autonomous Underwater Vehicles Using 3D Dubins Curves †

    PubMed Central

    Zhang, Meiyan; Zheng, Yahong Rosa

    2017-01-01

    This paper investigates the task assignment and path planning problem for multiple AUVs in three dimensional (3D) underwater wireless sensor networks where nonholonomic motion constraints of underwater AUVs in 3D space are considered. The multi-target task assignment and path planning problem is modeled by the Multiple Traveling Sales Person (MTSP) problem and the Genetic Algorithm (GA) is used to solve the MTSP problem with Euclidean distance as the cost function and the Tour Hop Balance (THB) or Tour Length Balance (TLB) constraints as the stop criterion. The resulting tour sequences are mapped to 2D Dubins curves in the X−Y plane, and then interpolated linearly to obtain the Z coordinates. We demonstrate that the linear interpolation fails to achieve G1 continuity in the 3D Dubins path for multiple targets. Therefore, the interpolated 3D Dubins curves are checked against the AUV dynamics constraint and the ones satisfying the constraint are accepted to finalize the 3D Dubins curve selection. Simulation results demonstrate that the integration of the 3D Dubins curve with the MTSP model is successful and effective for solving the 3D target assignment and path planning problem. PMID:28696377

  20. Task Assignment and Path Planning for Multiple Autonomous Underwater Vehicles Using 3D Dubins Curves †.

    PubMed

    Cai, Wenyu; Zhang, Meiyan; Zheng, Yahong Rosa

    2017-07-11

    This paper investigates the task assignment and path planning problem for multiple AUVs in three dimensional (3D) underwater wireless sensor networks where nonholonomic motion constraints of underwater AUVs in 3D space are considered. The multi-target task assignment and path planning problem is modeled by the Multiple Traveling Sales Person (MTSP) problem and the Genetic Algorithm (GA) is used to solve the MTSP problem with Euclidean distance as the cost function and the Tour Hop Balance (THB) or Tour Length Balance (TLB) constraints as the stop criterion. The resulting tour sequences are mapped to 2D Dubins curves in the X - Y plane, and then interpolated linearly to obtain the Z coordinates. We demonstrate that the linear interpolation fails to achieve G 1 continuity in the 3D Dubins path for multiple targets. Therefore, the interpolated 3D Dubins curves are checked against the AUV dynamics constraint and the ones satisfying the constraint are accepted to finalize the 3D Dubins curve selection. Simulation results demonstrate that the integration of the 3D Dubins curve with the MTSP model is successful and effective for solving the 3D target assignment and path planning problem.

  1. Frequency dependence of sensitivities in second-order RC active filters

    NASA Astrophysics Data System (ADS)

    Kunieda, T.; Hiramatsu, Y.; Fukui, A.

    1980-02-01

    This paper presents that gain and phase sensitivities to some element in biquadratic filters approximately constitute a circle on the complex sensitivity plane, provided that the quality factor Q of the circuit is appreciably larger than unity. Moreover, the group delay sensitivity is represented by the imaginary part of a cardioid. Using these results, bounds of maximum values of gain, phase, and group delay sensitivities are obtained. Further, it is proved that the maximum values of these sensitivities can be simultaneously minimized by minimizing the absolute value of the transfer function sensitivity at the center frequency provided that w(0)-sensitivities are constant and do not contain design parameters. Next, a statistical variability measure for the optimal-filter design is proposed. Finally, the relation between some variability measures proposed to the present time is made clear.

  2. ``Loose spins'' in Fe/Cu/Fe(001) structures

    NASA Astrophysics Data System (ADS)

    Heinrich, B.; Celinski, Z.; Liao, L. X.; From, M.; Cochran, J. F.

    1994-05-01

    Slonczewski recently proposed a model for the exchange coupling between ferromagnetic layers separated by a nonferromagnetic spacer based on the concept of ``loose spins.'' ``Loose spins'' contribute to the total exchange energy. We have studied the role of ``loose spins'' in bcc Fe/Cu/Fe(001) structures. bcc Fe/Cu/Fe(001) trilayers deposited at room temperature were investigated extensively in our previous studies. In our ``loose spin'' studies, the Fe was added inside the Cu interlayer. Several structures were atomically engineered in order to test the behavior of ``loose spins:'' One additional atomic layer of an (Fe+Cu) alloy were located in appropriate positions in a Cu spacer. The bilinear and biquadratic exchange coupling in the above structures was quantitatively studied with FMR in the temperature range 77-370 K and with MOKE at RT.

  3. Show, Don't Tell: Using Photographic "Snapsignments" to Advance and Assess Creative Problem Solving

    ERIC Educational Resources Information Center

    Machin, Jane E.

    2016-01-01

    Traditional assignments that aim to develop and evaluate creative problem solving skills are frequently foregone in large marketing classes due to the daunting grading prospect they present. Here, a new assessment method is introduced: the "snapsignment." Through photography, individual projects can be assigned that promote higher order…

  4. Autonomous Guidance Strategy for Spacecraft Formations and Reconfiguration Maneuvers

    NASA Astrophysics Data System (ADS)

    Wahl, Theodore P.

    A guidance strategy for autonomous spacecraft formation reconfiguration maneuvers is presented. The guidance strategy is presented as an algorithm that solves the linked assignment and delivery problems. The assignment problem is the task of assigning the member spacecraft of the formation to their new positions in the desired formation geometry. The guidance algorithm uses an auction process (also called an "auction algorithm''), presented in the dissertation, to solve the assignment problem. The auction uses the estimated maneuver and time of flight costs between the spacecraft and targets to create assignments which minimize a specific "expense'' function for the formation. The delivery problem is the task of delivering the spacecraft to their assigned positions, and it is addressed through one of two guidance schemes described in this work. The first is a delivery scheme based on artificial potential function (APF) guidance. APF guidance uses the relative distances between the spacecraft, targets, and any obstacles to design maneuvers based on gradients of potential fields. The second delivery scheme is based on model predictive control (MPC); this method uses a model of the system dynamics to plan a series of maneuvers designed to minimize a unique cost function. The guidance algorithm uses an analytic linearized approximation of the relative orbital dynamics, the Yamanaka-Ankersen state transition matrix, in the auction process and in both delivery methods. The proposed guidance strategy is successful, in simulations, in autonomously assigning the members of the formation to new positions and in delivering the spacecraft to these new positions safely using both delivery methods. This guidance algorithm can serve as the basis for future autonomous guidance strategies for spacecraft formation missions.

  5. WWC Review of the Report "Effects of Problem Based Economics on High School Economics Instruction"

    ERIC Educational Resources Information Center

    What Works Clearinghouse, 2012

    2012-01-01

    The study described in this report included 128 high school economics teachers from 106 schools in Arizona and California, half of whom were randomly assigned to the "Problem Based Economics Instruction" condition and half of whom were randomly assigned to the comparison condition. High levels of teacher attrition occurred after…

  6. Neural Mechanisms of Credit Assignment in a Multicue Environment

    PubMed Central

    Kolling, Nils; Brown, Joshua W.; Rushworth, Matthew

    2016-01-01

    In complex environments, many potential cues can guide a decision or be assigned responsibility for the outcome of the decision. We know little, however, about how humans and animals select relevant information sources that should guide behavior. We show that subjects solve this relevance selection and credit assignment problem by selecting one cue and its association with a particular outcome as the main focus of a hypothesis. To do this, we examined learning while using a task design that allowed us to estimate the focus of each subject's hypotheses on a trial-by-trial basis. When a prediction is confirmed by the outcome, then credit for the outcome is assigned to that cue rather than an alternative. Activity in medial frontal cortex is associated with the assignment of credit to the cue that is the main focus of the hypothesis. However, when the outcome disconfirms a prediction, the focus shifts between cues, and the credit for the outcome is assigned to an alternative cue. This process of reselection for credit assignment to an alternative cue is associated with lateral orbitofrontal cortex. SIGNIFICANCE STATEMENT Learners should infer which features of environments are predictive of significant events, such as rewards. This “credit assignment” problem is particularly challenging when any of several cues might be predictive. We show that human subjects solve the credit assignment problem by implicitly “hypothesizing” which cue is relevant for predicting subsequent outcomes, and then credit is assigned according to this hypothesis. This process is associated with a distinctive pattern of activity in a part of medial frontal cortex. By contrast, when unexpected outcomes occur, hypotheses are redirected toward alternative cues, and this process is associated with activity in lateral orbitofrontal cortex. PMID:26818500

  7. Optimal assignment of workers to supporting services in a hospital

    NASA Astrophysics Data System (ADS)

    Sawik, Bartosz; Mikulik, Jerzy

    2008-01-01

    Supporting services play an important role in health care institutions such as hospitals. This paper presents an application of operations research model for optimal allocation of workers among supporting services in a public hospital. The services include logistics, inventory management, financial management, operations management, medical analysis, etc. The optimality criterion of the problem is to minimize operations costs of supporting services subject to some specific constraints. The constraints represent specific conditions for resource allocation in a hospital. The overall problem is formulated as an integer program in the literature known as the assignment problem, where the decision variables represent the assignment of people to various jobs. The results of some computational experiments modeled on a real data from a selected Polish hospital are reported.

  8. A modified generalized extremal optimization algorithm for the quay crane scheduling problem with interference constraints

    NASA Astrophysics Data System (ADS)

    Guo, Peng; Cheng, Wenming; Wang, Yi

    2014-10-01

    The quay crane scheduling problem (QCSP) determines the handling sequence of tasks at ship bays by a set of cranes assigned to a container vessel such that the vessel's service time is minimized. A number of heuristics or meta-heuristics have been proposed to obtain the near-optimal solutions to overcome the NP-hardness of the problem. In this article, the idea of generalized extremal optimization (GEO) is adapted to solve the QCSP with respect to various interference constraints. The resulting GEO is termed the modified GEO. A randomized searching method for neighbouring task-to-QC assignments to an incumbent task-to-QC assignment is developed in executing the modified GEO. In addition, a unidirectional search decoding scheme is employed to transform a task-to-QC assignment to an active quay crane schedule. The effectiveness of the developed GEO is tested on a suite of benchmark problems introduced by K.H. Kim and Y.M. Park in 2004 (European Journal of Operational Research, Vol. 156, No. 3). Compared with other well-known existing approaches, the experiment results show that the proposed modified GEO is capable of obtaining the optimal or near-optimal solution in a reasonable time, especially for large-sized problems.

  9. Process-based Assignment-Setting Change for Support of Overcoming Bottlenecks in Learning by Problem-Posing in Arithmetic Word Problems

    NASA Astrophysics Data System (ADS)

    Supianto, A. A.; Hayashi, Y.; Hirashima, T.

    2017-02-01

    Problem-posing is well known as an effective activity to learn problem-solving methods. Monsakun is an interactive problem-posing learning environment to facilitate arithmetic word problems learning for one operation of addition and subtraction. The characteristic of Monsakun is problem-posing as sentence-integration that lets learners make a problem of three sentences. Monsakun provides learners with five or six sentences including dummies, which are designed through careful considerations by an expert teacher as a meaningful distraction to the learners in order to learn the structure of arithmetic word problems. The results of the practical use of Monsakun in elementary schools show that many learners have difficulties in arranging the proper answer at the high level of assignments. The analysis of the problem-posing process of such learners found that their misconception of arithmetic word problems causes impasses in their thinking and mislead them to use dummies. This study proposes a method of changing assignments as a support for overcoming bottlenecks of thinking. In Monsakun, the bottlenecks are often detected as a frequently repeated use of a specific dummy. If such dummy can be detected, it is the key factor to support learners to overcome their difficulty. This paper discusses how to detect the bottlenecks and to realize such support in learning by problem-posing.

  10. Fleet Assignment Using Collective Intelligence

    NASA Technical Reports Server (NTRS)

    Antoine, Nicolas E.; Bieniawski, Stefan R.; Kroo, Ilan M.; Wolpert, David H.

    2004-01-01

    Product distribution theory is a new collective intelligence-based framework for analyzing and controlling distributed systems. Its usefulness in distributed stochastic optimization is illustrated here through an airline fleet assignment problem. This problem involves the allocation of aircraft to a set of flights legs in order to meet passenger demand, while satisfying a variety of linear and non-linear constraints. Over the course of the day, the routing of each aircraft is determined in order to minimize the number of required flights for a given fleet. The associated flow continuity and aircraft count constraints have led researchers to focus on obtaining quasi-optimal solutions, especially at larger scales. In this paper, the authors propose the application of this new stochastic optimization algorithm to a non-linear objective cold start fleet assignment problem. Results show that the optimizer can successfully solve such highly-constrained problems (130 variables, 184 constraints).

  11. An analysis of spectral envelope-reduction via quadratic assignment problems

    NASA Technical Reports Server (NTRS)

    George, Alan; Pothen, Alex

    1994-01-01

    A new spectral algorithm for reordering a sparse symmetric matrix to reduce its envelope size was described. The ordering is computed by associating a Laplacian matrix with the given matrix and then sorting the components of a specified eigenvector of the Laplacian. In this paper, we provide an analysis of the spectral envelope reduction algorithm. We described related 1- and 2-sum problems; the former is related to the envelope size, while the latter is related to an upper bound on the work involved in an envelope Cholesky factorization scheme. We formulate the latter two problems as quadratic assignment problems, and then study the 2-sum problem in more detail. We obtain lower bounds on the 2-sum by considering a projected quadratic assignment problem, and then show that finding a permutation matrix closest to an orthogonal matrix attaining one of the lower bounds justifies the spectral envelope reduction algorithm. The lower bound on the 2-sum is seen to be tight for reasonably 'uniform' finite element meshes. We also obtain asymptotically tight lower bounds for the envelope size for certain classes of meshes.

  12. Towards Automated Structure-Based NMR Resonance Assignment

    NASA Astrophysics Data System (ADS)

    Jang, Richard; Gao, Xin; Li, Ming

    We propose a general framework for solving the structure-based NMR backbone resonance assignment problem. The core is a novel 0-1 integer programming model that can start from a complete or partial assignment, generate multiple assignments, and model not only the assignment of spins to residues, but also pairwise dependencies consisting of pairs of spins to pairs of residues. It is still a challenge for automated resonance assignment systems to perform the assignment directly from spectra without any manual intervention. To test the feasibility of this for structure-based assignment, we integrated our system with our automated peak picking and sequence-based resonance assignment system to obtain an assignment for the protein TM1112 with 91% recall and 99% precision without manual intervention. Since using a known structure has the potential to allow one to use only N-labeled NMR data and avoid the added expense of using C-labeled data, we work towards the goal of automated structure-based assignment using only such labeled data. Our system reduced the assignment error of Xiong-Pandurangan-Bailey-Kellogg's contact replacement (CR) method, which to our knowledge is the most error-tolerant method for this problem, by 5 folds on average. By using an iterative algorithm, our system has the added capability of using the NOESY data to correct assignment errors due to errors in predicting the amino acid and secondary structure type of each spin system. On a publicly available data set for Ubiquitin, where the type prediction accuracy is 83%, we achieved 91% assignment accuracy, compared to the 59% accuracy that was obtained without correcting for typing errors.

  13. A flexible nonlinear diffusion acceleration method for the S N transport equations discretized with discontinuous finite elements

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

    Schunert, Sebastian; Wang, Yaqi; Gleicher, Frederick

    This paper presents a flexible nonlinear diffusion acceleration (NDA) method that discretizes both the S N transport equation and the diffusion equation using the discontinuous finite element method (DFEM). The method is flexible in that the diffusion equation can be discretized on a coarser mesh with the only restriction that it is nested within the transport mesh and the FEM shape function orders of the two equations can be different. The consistency of the transport and diffusion solutions at convergence is defined by using a projection operator mapping the transport into the diffusion FEM space. The diffusion weak form ismore » based on the modified incomplete interior penalty (MIP) diffusion DFEM discretization that is extended by volumetric drift, interior face, and boundary closure terms. In contrast to commonly used coarse mesh finite difference (CMFD) methods, the presented NDA method uses a full FEM discretized diffusion equation for acceleration. Suitable projection and prolongation operators arise naturally from the FEM framework. Via Fourier analysis and numerical experiments for a one-group, fixed source problem the following properties of the NDA method are established for structured quadrilateral meshes: (1) the presented method is unconditionally stable and effective in the presence of mild material heterogeneities if the same mesh and identical shape functions either of the bilinear or biquadratic type are used, (2) the NDA method remains unconditionally stable in the presence of strong heterogeneities, (3) the NDA method with bilinear elements extends the range of effectiveness and stability by a factor of two when compared to CMFD if a coarser diffusion mesh is selected. In addition, the method is tested for solving the C5G7 multigroup, eigenvalue problem using coarse and fine mesh acceleration. Finally, while NDA does not offer an advantage over CMFD for fine mesh acceleration, it reduces the iteration count required for convergence by almost a factor of two in the case of coarse mesh acceleration.« less

  14. A flexible nonlinear diffusion acceleration method for the S N transport equations discretized with discontinuous finite elements

    DOE PAGES

    Schunert, Sebastian; Wang, Yaqi; Gleicher, Frederick; ...

    2017-02-21

    This paper presents a flexible nonlinear diffusion acceleration (NDA) method that discretizes both the S N transport equation and the diffusion equation using the discontinuous finite element method (DFEM). The method is flexible in that the diffusion equation can be discretized on a coarser mesh with the only restriction that it is nested within the transport mesh and the FEM shape function orders of the two equations can be different. The consistency of the transport and diffusion solutions at convergence is defined by using a projection operator mapping the transport into the diffusion FEM space. The diffusion weak form ismore » based on the modified incomplete interior penalty (MIP) diffusion DFEM discretization that is extended by volumetric drift, interior face, and boundary closure terms. In contrast to commonly used coarse mesh finite difference (CMFD) methods, the presented NDA method uses a full FEM discretized diffusion equation for acceleration. Suitable projection and prolongation operators arise naturally from the FEM framework. Via Fourier analysis and numerical experiments for a one-group, fixed source problem the following properties of the NDA method are established for structured quadrilateral meshes: (1) the presented method is unconditionally stable and effective in the presence of mild material heterogeneities if the same mesh and identical shape functions either of the bilinear or biquadratic type are used, (2) the NDA method remains unconditionally stable in the presence of strong heterogeneities, (3) the NDA method with bilinear elements extends the range of effectiveness and stability by a factor of two when compared to CMFD if a coarser diffusion mesh is selected. In addition, the method is tested for solving the C5G7 multigroup, eigenvalue problem using coarse and fine mesh acceleration. Finally, while NDA does not offer an advantage over CMFD for fine mesh acceleration, it reduces the iteration count required for convergence by almost a factor of two in the case of coarse mesh acceleration.« less

  15. Developing a feasible neighbourhood search for solving hub location problem in a communication network

    NASA Astrophysics Data System (ADS)

    Rakhmawati, Fibri; Mawengkang, Herman; Buulolo, F.; Mardiningsih

    2018-01-01

    The hub location with single assignment is the problem of locating hubs and assigning the terminal nodes to hubs in order to minimize the cost of hub installation and the cost of routing the traffic in the network. There may also be capacity restrictions on the amount of traffic that can transit by hubs. This paper discusses how to model the polyhedral properties of the problems and develop a feasible neighbourhood search method to solve the model.

  16. An automated framework for NMR resonance assignment through simultaneous slice picking and spin system forming.

    PubMed

    Abbas, Ahmed; Guo, Xianrong; Jing, Bing-Yi; Gao, Xin

    2014-06-01

    Despite significant advances in automated nuclear magnetic resonance-based protein structure determination, the high numbers of false positives and false negatives among the peaks selected by fully automated methods remain a problem. These false positives and negatives impair the performance of resonance assignment methods. One of the main reasons for this problem is that the computational research community often considers peak picking and resonance assignment to be two separate problems, whereas spectroscopists use expert knowledge to pick peaks and assign their resonances at the same time. We propose a novel framework that simultaneously conducts slice picking and spin system forming, an essential step in resonance assignment. Our framework then employs a genetic algorithm, directed by both connectivity information and amino acid typing information from the spin systems, to assign the spin systems to residues. The inputs to our framework can be as few as two commonly used spectra, i.e., CBCA(CO)NH and HNCACB. Different from the existing peak picking and resonance assignment methods that treat peaks as the units, our method is based on 'slices', which are one-dimensional vectors in three-dimensional spectra that correspond to certain ([Formula: see text]) values. Experimental results on both benchmark simulated data sets and four real protein data sets demonstrate that our method significantly outperforms the state-of-the-art methods while using a less number of spectra than those methods. Our method is freely available at http://sfb.kaust.edu.sa/Pages/Software.aspx.

  17. Analysis of labor employment assessment on production machine to minimize time production

    NASA Astrophysics Data System (ADS)

    Hernawati, Tri; Suliawati; Sari Gumay, Vita

    2018-03-01

    Every company both in the field of service and manufacturing always trying to pass efficiency of it’s resource use. One resource that has an important role is labor. Labor has different efficiency levels for different jobs anyway. Problems related to the optimal allocation of labor that has different levels of efficiency for different jobs are called assignment problems, which is a special case of linear programming. In this research, Analysis of Labor Employment Assesment on Production Machine to Minimize Time Production, in PT PDM is done by using Hungarian algorithm. The aim of the research is to get the assignment of optimal labor on production machine to minimize time production. The results showed that the assignment of existing labor is not suitable because the time of completion of the assignment is longer than the assignment by using the Hungarian algorithm. By applying the Hungarian algorithm obtained time savings of 16%.

  18. Analyzing the multiple-target-multiple-agent scenario using optimal assignment algorithms

    NASA Astrophysics Data System (ADS)

    Kwok, Kwan S.; Driessen, Brian J.; Phillips, Cynthia A.; Tovey, Craig A.

    1997-09-01

    This work considers the problem of maximum utilization of a set of mobile robots with limited sensor-range capabilities and limited travel distances. The robots are initially in random positions. A set of robots properly guards or covers a region if every point within the region is within the effective sensor range of at least one vehicle. We wish to move the vehicles into surveillance positions so as to guard or cover a region, while minimizing the maximum distance traveled by any vehicle. This problem can be formulated as an assignment problem, in which we must optimally decide which robot to assign to which slot of a desired matrix of grid points. The cost function is the maximum distance traveled by any robot. Assignment problems can be solved very efficiently. Solution times for one hundred robots took only seconds on a silicon graphics crimson workstation. The initial positions of all the robots can be sampled by a central base station and their newly assigned positions communicated back to the robots. Alternatively, the robots can establish their own coordinate system with the origin fixed at one of the robots and orientation determined by the compass bearing of another robot relative to this robot. This paper presents example solutions to the multiple-target-multiple-agent scenario using a matching algorithm. Two separate cases with one hundred agents in each were analyzed using this method. We have found these mobile robot problems to be a very interesting application of network optimization methods, and we expect this to be a fruitful area for future research.

  19. Protein Side-Chain Resonance Assignment and NOE Assignment Using RDC-Defined Backbones without TOCSY Data3

    PubMed Central

    Zeng, Jianyang; Zhou, Pei; Donald, Bruce Randall

    2011-01-01

    One bottleneck in NMR structure determination lies in the laborious and time-consuming process of side-chain resonance and NOE assignments. Compared to the well-studied backbone resonance assignment problem, automated side-chain resonance and NOE assignments are relatively less explored. Most NOE assignment algorithms require nearly complete side-chain resonance assignments from a series of through-bond experiments such as HCCH-TOCSY or HCCCONH. Unfortunately, these TOCSY experiments perform poorly on large proteins. To overcome this deficiency, we present a novel algorithm, called NASCA (NOE Assignment and Side-Chain Assignment), to automate both side-chain resonance and NOE assignments and to perform high-resolution protein structure determination in the absence of any explicit through-bond experiment to facilitate side-chain resonance assignment, such as HCCH-TOCSY. After casting the assignment problem into a Markov Random Field (MRF), NASCA extends and applies combinatorial protein design algorithms to compute optimal assignments that best interpret the NMR data. The MRF captures the contact map information of the protein derived from NOESY spectra, exploits the backbone structural information determined by RDCs, and considers all possible side-chain rotamers. The complexity of the combinatorial search is reduced by using a dead-end elimination (DEE) algorithm, which prunes side-chain resonance assignments that are provably not part of the optimal solution. Then an A* search algorithm is employed to find a set of optimal side-chain resonance assignments that best fit the NMR data. These side-chain resonance assignments are then used to resolve the NOE assignment ambiguity and compute high-resolution protein structures. Tests on five proteins show that NASCA assigns resonances for more than 90% of side-chain protons, and achieves about 80% correct assignments. The final structures computed using the NOE distance restraints assigned by NASCA have backbone RMSD 0.8 – 1.5 Å from the reference structures determined by traditional NMR approaches. PMID:21706248

  20. Optimization of municipal waste collection scheduling and routing using vehicle assignment problem (case study of Surabaya city waste collection)

    NASA Astrophysics Data System (ADS)

    Ramdhani, M. N.; Baihaqi, I.; Siswanto, N.

    2018-04-01

    Waste collection and disposal become a major problem for many metropolitan cities. Growing population, limited vehicles, and increased road traffic make the waste transportation become more complex. Waste collection involves some key considerations, such as vehicle assignment, vehicle routes, and vehicle scheduling. In the scheduling process, each vehicle has a scheduled departure that serve each route. Therefore, vehicle’s assignments should consider the time required to finish one assigment on that route. The objective of this study is to minimize the number of vehicles needed to serve all routes by developing a mathematical model which uses assignment problem approach. The first step is to generated possible routes from the existing routes, followed by vehicle assignments for those certain routes. The result of the model shows fewer vehicles required to perform waste collection asa well as the the number of journeys that the vehicle to collect the waste to the landfill. The comparison of existing conditions with the model result indicates that the latter’s has better condition than the existing condition because each vehicle with certain route has an equal workload, all the result’s model has the maximum of two journeys for each route.

  1. Maternal education preferences moderate the effects of mandatory employment and education programs on child positive and problem behaviors

    PubMed Central

    Gassman-Pines, Anna; Godfrey, Erin B.; Yoshikawa, Hirokazu

    2012-01-01

    Grounded in Person-Environment Fit Theory, this study examined whether low-income mothers' preferences for education moderated the effects of employment- and education-focused welfare programs on children's positive and problem behaviors. The sample included 1,365 families with children between ages 3 and 5 at study entry. Results 5 years after random assignment, when children were ages 8 to 10, indicated that mothers' education preferences did moderate program impacts on teacher-reported child behavior problems and positive behavior. Children whose mothers were assigned to the education program were rated by teachers to have less externalizing behavior and more positive behavior than children whose mothers were assigned to the employment program, but only when mothers had strong preferences for education. PMID:22861169

  2. Supervising Unsuccessful Student Teaching Assignments: Two Terminator's Tales.

    ERIC Educational Resources Information Center

    St. Maurice, Henry

    2001-01-01

    Discusses problems that arise when there is a conflict between a student teacher and the supervising teacher and when a student teacher does not perform satisfactorily. Focuses on how supervisors deal with failed assignments and how beginning teachers improve their teaching and learn from failed assignments. (Contains 21 references.) (JOW)

  3. The Biomes of Homewood: Interactive Map Software

    ERIC Educational Resources Information Center

    Shingles, Richard; Feist, Theron; Brosnan, Rae

    2005-01-01

    To build a learning community, the General Biology faculty at Johns Hopkins University conducted collaborative, problem-based learning assignments outside of class in which students are assigned to specific areas on campus, and gather and report data about their area. To overcome the logistics challenges presented by conducting such assignments in…

  4. Dielectric properties of ferroelectric betaine phosphite crystals with a high degree of deuteration

    NASA Astrophysics Data System (ADS)

    Balashova, E. V.; Krichevtsov, B. B.; Yurko, E. I.; Svinarev, F. B.; Pankova, G. A.

    2015-12-01

    The dielectric properties of deuterated betaine phosphite crystals with a high degree of deuteration in the region of the antiferrodistorsive (at T = T c1) and ferroelectric (at T = T c2) phase transitions have been investigated. The temperature behavior of the dielectric permittivity of betaine phosphite and deuterated betaine phosphite has been described within the framework of the Landau thermodynamic model taking into account the biquadratic coupling between the polar order parameter of the ferroelectric transition and the nonpolar order parameter of the antiferrodistorsive phase transition. It has been shown that an increase in the degree of deuteration leads to a decrease in the coupling between the order parameters. An increase in the temperature of the ferroelectric phase transition due to the deuteration of betaine phosphite is caused by an increase in the dielectric permittivity in the symmetric phase above the temperature of the antiferrodistorsive phase transition.

  5. Stationary responses of a Rayleigh viscoelastic system with zero barrier impacts under external random excitation.

    PubMed

    Wang, Deli; Xu, Wei; Zhao, Xiangrong

    2016-03-01

    This paper aims to deal with the stationary responses of a Rayleigh viscoelastic system with zero barrier impacts under external random excitation. First, the original stochastic viscoelastic system is converted to an equivalent stochastic system without viscoelastic terms by approximately adding the equivalent stiffness and damping. Relying on the means of non-smooth transformation of state variables, the above system is replaced by a new system without an impact term. Then, the stationary probability density functions of the system are observed analytically through stochastic averaging method. By considering the effects of the biquadratic nonlinear damping coefficient and the noise intensity on the system responses, the effectiveness of the theoretical method is tested by comparing the analytical results with those generated from Monte Carlo simulations. Additionally, it does deserve attention that some system parameters can induce the occurrence of stochastic P-bifurcation.

  6. Spin nematics next to spin singlets

    NASA Astrophysics Data System (ADS)

    Yokoyama, Yuto; Hotta, Chisa

    2018-05-01

    We provide a route to generate nematic order in a spin-1/2 system. Unlike the well-known magnon-binding mechanism, our spin nematics requires neither the frustration effect nor spin polarization in a high field or in the vicinity of a ferromagnet, but instead appears next to the spin singlet phase. We start from a state consisting of a quantum spin-1/2 singlet dimer placed on each site of a triangular lattice, and show that interdimer ring exchange interactions efficiently dope the SU(2) triplets that itinerate and interact, easily driving a stable singlet state to either Bose-Einstein condensates or a triplet crystal, some hosting a spin nematic order. A variety of roles the ring exchange serves includes the generation of a bilinear-biquadratic interaction between nearby triplets, which is responsible for the emergent nematic order separated from the singlet phase by a first-order transition.

  7. Rotomagnetic coupling in fine-grained multiferroic BiFe O3 : Theory and experiment

    NASA Astrophysics Data System (ADS)

    Morozovska, Anna N.; Eliseev, Eugene A.; Glinchuk, Maya D.; Fesenko, Olena M.; Shvartsman, Vladimir V.; Gopalan, Venkatraman; Silibin, Maxim V.; Karpinsky, Dmitry V.

    2018-04-01

    Using Landau-Ginzburg-Devonshire (LGD) theory for BiFe O3 dense fine-grained ceramics with quasispherical grains and nanosized intergrain spaces enriched by elastic defects, we calculated a surprisingly strong size-induced increase in the antiferromagnetic transition temperature caused by the joint action of rotomagnetic and magnetostrictive coupling. Notably, all parameters included in the LGD functional have been extracted from experiments, not assumed. Complementarily, we performed experiments for dense BiFe O3 ceramics, which revealed that the shift of the antiferromagnetic transition is to TN˜690 K instead of TN˜645 K for a single crystal. To explain the result theoretically, we consider the possibility of controlling the antiferromagnetic state of multiferroic BiFe O3 via biquadratic antiferrodistortive rotomagnetic, rotoelectric, magnetoelectric, and magnetostrictive couplings. According to our calculations, the highest contribution is the rotostriction contribution, while the magnetostrictive and electrostriction contributions appear smaller.

  8. Rigorous decoupling between edge states in frustrated spin chains and ladders

    NASA Astrophysics Data System (ADS)

    Chepiga, Natalia; Mila, Frédéric

    2018-05-01

    We investigate the occurrence of exact zero modes in one-dimensional quantum magnets of finite length that possess edge states. Building on conclusions first reached in the context of the spin-1/2 X Y chain in a field and then for the spin-1 J1-J2 Heisenberg model, we show that the development of incommensurate correlations in the bulk invariably leads to oscillations in the sign of the coupling between edge states, and hence to exact zero energy modes at the crossing points where the coupling between the edge states rigorously vanishes. This is true regardless of the origin of the frustration (e.g., next-nearest-neighbor coupling or biquadratic coupling for the spin-1 chain), of the value of the bulk spin (we report on spin-1/2, spin-1, and spin-2 examples), and of the value of the edge-state emergent spin (spin-1/2 or spin-1).

  9. Positive-Negative Birefringence in Multiferroic Layered Metasurfaces.

    PubMed

    Khomeriki, R; Chotorlishvili, L; Tralle, I; Berakdar, J

    2016-11-09

    We uncover and identify the regime for a magnetically and ferroelectrically controllable negative refraction of a light-traversing multiferroic, oxide-based metastructure consisting of alternating nanoscopic ferroelectric (SrTiO 3 ) and ferromagnetic (Y 3 Fe 2 (FeO 4 ) 3 , YIG) layers. We perform analytical and numerical simulations based on discretized, coupled equations for the self-consistent Maxwell/ferroelectric/ferromagnetic dynamics and obtain a biquadratic relation for the refractive index. Various scenarios of ordinary and negative refraction in different frequency ranges are analyzed and quantified by simple analytical formula that are confirmed by full-fledge numerical simulations. Electromagnetic waves injected at the edges of the sample are propagated exactly numerically. We discovered that, for particular GHz frequencies, waves with different polarizations are characterized by different signs of the refractive index, giving rise to novel types of phenomena such as a positive-negative birefringence effect and magnetically controlled light trapping and accelerations.

  10. Multicasting for all-optical multifiber networks

    NASA Astrophysics Data System (ADS)

    Kã¶Ksal, Fatih; Ersoy, Cem

    2007-02-01

    All-optical wavelength-routed WDM WANs can support the high bandwidth and the long session duration requirements of the application scenarios such as interactive distance learning or on-line diagnosis of patients simultaneously in different hospitals. However, multifiber and limited sparse light splitting and wavelength conversion capabilities of switches result in a difficult optimization problem. We attack this problem using a layered graph model. The problem is defined as a k-edge-disjoint degree-constrained Steiner tree problem for routing and fiber and wavelength assignment of k multicasts. A mixed integer linear programming formulation for the problem is given, and a solution using CPLEX is provided. However, the complexity of the problem grows quickly with respect to the number of edges in the layered graph, which depends on the number of nodes, fibers, wavelengths, and multicast sessions. Hence, we propose two heuristics layered all-optical multicast algorithm [(LAMA) and conservative fiber and wavelength assignment (C-FWA)] to compare with CPLEX, existing work, and unicasting. Extensive computational experiments show that LAMA's performance is very close to CPLEX, and it is significantly better than existing work and C-FWA for nearly all metrics, since LAMA jointly optimizes routing and fiber-wavelength assignment phases compared with the other candidates, which attack the problem by decomposing two phases. Experiments also show that important metrics (e.g., session and group blocking probability, transmitter wavelength, and fiber conversion resources) are adversely affected by the separation of two phases. Finally, the fiber-wavelength assignment strategy of C-FWA (Ex-Fit) uses wavelength and fiber conversion resources more effectively than the First Fit.

  11. Contributions au probleme d'affectation des types d'avion

    NASA Astrophysics Data System (ADS)

    Belanger, Nicolas

    In this thesis, we approach the problem of assigning aircraft types to flights (what is called aircraft fleet assignment) in a strategic planning context. The literature mentions many studies considering this problem on a daily flight schedule basis, but the proposed models do no allow to consider many elements that are either necessary to assure the practical feasibility of the solutions, or relevant to get more beneficial solutions. After describing the practical context of the problem (Chapter 1) and presenting the literature on the subject (Chapter 2), we propose new models and solution approaches to improve the quality of' the solutions obtained. The general scheme of the thesis is presented in Chapter 3. We summarize here the models and solution approaches that we propose; and present the main elements of our conclusions. First, in Chapter 4, we consider the problem of aircraft fleet Assignment over a weekly flight schedule, integrating into the objective an homogeneity factor for driving the choice of the aircraft types for the flights with the same flight number over the week. We present an integer linear model based on a time-space multicommodity network. This model includes, among others, decision variables relative to the aircraft type assigned to each flight and to the dominant aircraft type assigned to each flight number. We present in Chapter 5 the results of a research project made in collaboration with Air Canada within a consulting contract. The project aimed at analyzing the relevance for the planners of using an optimization software to help them to first identify non profitable flight legs in the network, and second to efficiently establish the aircraft fleet assignment. In this chapter, we propose an iterative approach to take into account the fact that the passenger demand is not known on a leg basis, but rather on an origin-destination and departure time basis. Finally, in Chapter 6, we propose a model and a solution approach that aim at solving the fleet assignment problem over a periodic schedule in the case where there is a flexibility on the flight departure times and the fleet size must be minimized. Moreover, the objective of this model includes the impact on the passenger demand for each flight of the variation of the flight departure times and the closing of the departure times of consecutive flights connecting the same pairs of stations. (Abstract shortened by UMI.)

  12. The effect of wind and moisture gradients on the arbitrary assignment of cloud motions to a vertical coordinate system in two Sesame cases

    NASA Technical Reports Server (NTRS)

    Peslen, C. A.; Koch, S. E.; Uccellini, L. W.

    1984-01-01

    Satellite-derived cloud motion 'wind' vectors (CMV) are increasingly used in mesoscale and in global analyses, and questions have been raised regarding the uncertainty of the level assignment for the CMV. One of two major problems in selecting a level for the CMV is related to uncertainties in assigning the motion vector to either the cloud top or base. The second problem is related to the inability to transfer the 'wind' derived from the CMV at individually specified heights to a standard coordinated surface. The present investigation has the objective to determine if the arbitrary level assignment represents a serious obstacle to the use of cloud motion wind vectors in the mesoscale analysis of a severe storm environment.

  13. Multi Objective Decision Analysis for Assignment Problems

    DTIC Science & Technology

    2011-03-01

    needed data or try to get data from related databases. 2.3.8 Deterministic Analysis In order to determine an overall score for each...The views expressed in this thesis are those of the author and do not reflect the official policy or position of the Turkish Air...DECISION ANALYSIS FOR ASSIGNMENT PROBLEMS THESIS Presented to the Faculty Department of Operational Sciences Graduate School of

  14. Using the Same Problem with Different Techniques in Programming Assignments: An Empirical Study of Its Effectiveness

    ERIC Educational Resources Information Center

    Newby, Michael; Nguyen, ThuyUyen H.

    2010-01-01

    This paper examines the effectiveness of a technique that first appeared as a Teaching Tip in the Journal of Information Systems Education. In this approach the same problem is used in every programming assignment within a course, but the students are required to use different programming techniques. This approach was used in an intermediate C++…

  15. Integrated consensus-based frameworks for unmanned vehicle routing and targeting assignment

    NASA Astrophysics Data System (ADS)

    Barnawi, Waleed T.

    Unmanned aerial vehicles (UAVs) are increasingly deployed in complex and dynamic environments to perform multiple tasks cooperatively with other UAVs that contribute to overarching mission effectiveness. Studies by the Department of Defense (DoD) indicate future operations may include anti-access/area-denial (A2AD) environments which limit human teleoperator decision-making and control. This research addresses the problem of decentralized vehicle re-routing and task reassignments through consensus-based UAV decision-making. An Integrated Consensus-Based Framework (ICF) is formulated as a solution to the combined single task assignment problem and vehicle routing problem. The multiple assignment and vehicle routing problem is solved with the Integrated Consensus-Based Bundle Framework (ICBF). The frameworks are hierarchically decomposed into two levels. The bottom layer utilizes the renowned Dijkstra's Algorithm. The top layer addresses task assignment with two methods. The single assignment approach is called the Caravan Auction Algorithm (CarA) Algorithm. This technique extends the Consensus-Based Auction Algorithm (CBAA) to provide awareness for task completion by agents and adopt abandoned tasks. The multiple assignment approach called the Caravan Auction Bundle Algorithm (CarAB) extends the Consensus-Based Bundle Algorithm (CBBA) by providing awareness for lost resources, prioritizing remaining tasks, and adopting abandoned tasks. Research questions are investigated regarding the novelty and performance of the proposed frameworks. Conclusions regarding the research questions will be provided through hypothesis testing. Monte Carlo simulations will provide evidence to support conclusions regarding the research hypotheses for the proposed frameworks. The approach provided in this research addresses current and future military operations for unmanned aerial vehicles. However, the general framework implied by the proposed research is adaptable to any unmanned vehicle. Civil applications that involve missions where human observability would be limited could benefit from the independent UAV task assignment, such as exploration and fire surveillance are also notable uses for this approach.

  16. On the problem of resonance assignments in solid state NMR of uniformly 15N, 13C-labeled proteins

    NASA Astrophysics Data System (ADS)

    Tycko, Robert

    2015-04-01

    Determination of accurate resonance assignments from multidimensional chemical shift correlation spectra is one of the major problems in biomolecular solid state NMR, particularly for relative large proteins with less-than-ideal NMR linewidths. This article investigates the difficulty of resonance assignment, using a computational Monte Carlo/simulated annealing (MCSA) algorithm to search for assignments from artificial three-dimensional spectra that are constructed from the reported isotropic 15N and 13C chemical shifts of two proteins whose structures have been determined by solution NMR methods. The results demonstrate how assignment simulations can provide new insights into factors that affect the assignment process, which can then help guide the design of experimental strategies. Specifically, simulations are performed for the catalytic domain of SrtC (147 residues, primarily β-sheet secondary structure) and the N-terminal domain of MLKL (166 residues, primarily α-helical secondary structure). Assuming unambiguous residue-type assignments and four ideal three-dimensional data sets (NCACX, NCOCX, CONCA, and CANCA), uncertainties in chemical shifts must be less than 0.4 ppm for assignments for SrtC to be unique, and less than 0.2 ppm for MLKL. Eliminating CANCA data has no significant effect, but additionally eliminating CONCA data leads to more stringent requirements for chemical shift precision. Introducing moderate ambiguities in residue-type assignments does not have a significant effect.

  17. Due-Window Assignment Scheduling with Variable Job Processing Times

    PubMed Central

    Wu, Yu-Bin

    2015-01-01

    We consider a common due-window assignment scheduling problem jobs with variable job processing times on a single machine, where the processing time of a job is a function of its position in a sequence (i.e., learning effect) or its starting time (i.e., deteriorating effect). The problem is to determine the optimal due-windows, and the processing sequence simultaneously to minimize a cost function includes earliness, tardiness, the window location, window size, and weighted number of tardy jobs. We prove that the problem can be solved in polynomial time. PMID:25918745

  18. Learner-Centered Teaching and Improving Learning by Writing Down the Statement of Problems in an Introductory Physics Course

    NASA Astrophysics Data System (ADS)

    Aurora, Tarlok

    2005-04-01

    In a calculus-based introductory physics course, students were assigned to write the statements of word problems (along with the accompanying diagrams if any), analyze these, identify important concepts/equations and try to solve these end-of- chapter homework problems. They were required to bring to class their written assignment until the chapter was completed in lecture. These were quickly checked at the beginning of the class. In addition, re-doing selected solved examples in the textbook were assigned as homework. Where possible, students were asked to look for similarities between the solved-examples and the end-of-the-chapter problems, or occasionally these were brought to the students' attention. It was observed that many students were able to solve several of the solved-examples on the test even though the instructor had not solved these in class. This was seen as an improvement over the previous years. It made the students more responsible for their learning. Another benefit was that it alleviated the problems previously created by many students not bringing the textbooks to class. It allowed more time for problem solving/discussions in class.

  19. Frequency assignments for HFDF receivers in a search and rescue network

    NASA Astrophysics Data System (ADS)

    Johnson, Krista E.

    1990-03-01

    This thesis applies a multiobjective linear programming approach to the problem of assigning frequencies to high frequency direction finding (HFDF) receivers in a search-and-rescue network in order to maximize the expected number of geolocations of vessels in distress. The problem is formulated as a multiobjective integer linear programming problem. The integrality of the solutions is guaranteed by the totally unimodularity of the A-matrix. Two approaches are taken to solve the multiobjective linear programming problem: (1) the multiobjective simplex method as implemented in ADBASE; and (2) an iterative approach. In this approach, the individual objective functions are weighted and combined in a single additive objective function. The resulting single objective problem is expressed as a network programming problem and solved using SAS NETFLOW. The process is then repeated with different weightings for the objective functions. The solutions obtained from the multiobjective linear programs are evaluated using a FORTRAN program to determine which solution provides the greatest expected number of geolocations. This solution is then compared to the sample mean and standard deviation for the expected number of geolocations resulting from 10,000 random frequency assignments for the network.

  20. Temperature dependence of the exchange coupling in the Fe(001) whisker/11 ML Cr/20 ML Fe structure

    NASA Astrophysics Data System (ADS)

    From, M.; Liao, L. X.; Cochran, J. F.; Heinrich, B.

    1994-05-01

    The exchange coupling between iron layers separated by 11 monolayers (ML) of Cr(001) has been investigated using a structure in which the Cr(001) was grown on a bulk iron whisker Fe(001) surface at a temperature of approximately 300 °C. This temperature was selected to produce near optimum smoothness of the Cr layer. The Cr(001) deposition was followed by the deposition of 20 ML of Fe(001) at room temperature, and by the deposition of a 20 ML Au(001) protective layer. The frequencies corresponding to the magnetic excitations in this structure were measured by means of Brillouin light scattering (BLS). One of the observed frequencies corresponds to a surface mode in the bulk iron whisker. Another observed frequency corresponds to the lowest lying precessional mode of the magnetization in the 20 ML thick Fe(001) thin film. Typically, the thin film frequency exhibits a dependence on applied magnetic field that displays two cusps. The positions of the cusps are dependent on the exchange coupling between the 20 ML Fe film and the bulk iron substrate. The surface mode frequency increases monotonically with increasing field over most of the field range investigated. However, at the field corresponding to the low field cusp in the thin film frequency, the surface mode frequency undergoes an abrupt jump in magnitude. We have used the position of the cusps in the thin film data to deduce values for the bilinear, J1, and biquadratic, J2, coupling terms, where the coupling energy is written in the form EAB=-J1 cos(Δφ)+J2 cos2(Δφ); Δφ is the angle between the thin film and bulk iron magnetizations. Measurements of J1 and J2 have been carried out at six temperatures that span the range 100-350 K. Both J1 and J2 are found to depend strongly on temperature. The data are well described by the quadratic expression J2=-0.54+1.46 ×‖J1‖-0.52×J12, where J1 and J2 are expressed in erg/cm2. The large nonzero intercept and the linear term probably imply a significant intrinsic contribution to the biquadratic exchange.

  1. Fleet Assignment Using Collective Intelligence

    NASA Technical Reports Server (NTRS)

    Antoine, Nicolas E.; Bieniawski, Stefan R.; Kroo, Ilan M.; Wolpert, David H.

    2004-01-01

    Airline fleet assignment involves the allocation of aircraft to a set of flights legs in order to meet passenger demand, while satisfying a variety of constraints. Over the course of the day, the routing of each aircraft is determined in order to minimize the number of required flights for a given fleet. The associated flow continuity and aircraft count constraints have led researchers to focus on obtaining quasi-optimal solutions, especially at larger scales. In this paper, the authors propose the application of an agent-based integer optimization algorithm to a "cold start" fleet assignment problem. Results show that the optimizer can successfully solve such highly- constrained problems (129 variables, 184 constraints).

  2. Evaluation of Goal Programming for the Optimal Assignment of Inspectors to Construction Projects

    DTIC Science & Technology

    1988-09-01

    Inputs ..... .............. 90 Equation Coefficients . ....... .. 90 Weights, Priorities and the AHP . . 91 Right-Hand Side Values ........ .. 91...the AHP Hierarchy with k Levels . . 36 3. Sample Matrix for Pairwise Comparison ........ .. 37 4. Assignment of I and p for Example Problem...Weights for Example Problem ... 61 3. AHP Weights and Coefficient ci, Values. ........ 63 vii AFIT/GEM/LSM/88S-16 Abstract The purpose of this study was

  3. An Examination of Problems and Solutions Related to the Chronic "Revolving Door" Alcohol Abuser. DHSS Planning Guideline #1, Task Assignment #1.11. Long-Term Support, Chronic Alcoholism and Other Drug Abuse.

    ERIC Educational Resources Information Center

    Vick, John W.; Houden, Dorothy

    This report contains recommendations of a Wisconsin Task Assignment Steering Committee created to explore solutions to some significant problems facing adult chronic "revolving-detox-door" alcohol abusers (CRA's), persons with repeated admissions for detoxification services; and to examine the system that serves and funds them. This…

  4. Robotics and STEM Learning: Students' Achievements in Assignments According to the P3 Task Taxonomy--Practice, Problem Solving, and Projects

    ERIC Educational Resources Information Center

    Barak, Moshe; Assal, Muhammad

    2018-01-01

    This study presents the case of development and evaluation of a STEM-oriented 30-h robotics course for junior high school students (n = 32). Class activities were designed according to the P3 Task Taxonomy, which included: (1) practice-basic closed-ended tasks and exercises; (2) problem solving--small-scale open-ended assignments in which the…

  5. Scheduling Jobs and a Variable Maintenance on a Single Machine with Common Due-Date Assignment

    PubMed Central

    Wan, Long

    2014-01-01

    We investigate a common due-date assignment scheduling problem with a variable maintenance on a single machine. The goal is to minimize the total earliness, tardiness, and due-date cost. We derive some properties on an optimal solution for our problem. For a special case with identical jobs we propose an optimal polynomial time algorithm followed by a numerical example. PMID:25147861

  6. Knowledge-based design of generate-and-patch problem solvers that solve global resource assignment problems

    NASA Technical Reports Server (NTRS)

    Voigt, Kerstin

    1992-01-01

    We present MENDER, a knowledge based system that implements software design techniques that are specialized to automatically compile generate-and-patch problem solvers that satisfy global resource assignments problems. We provide empirical evidence of the superior performance of generate-and-patch over generate-and-test: even with constrained generation, for a global constraint in the domain of '2D-floorplanning'. For a second constraint in '2D-floorplanning' we show that even when it is possible to incorporate the constraint into a constrained generator, a generate-and-patch problem solver may satisfy the constraint more rapidly. We also briefly summarize how an extended version of our system applies to a constraint in the domain of 'multiprocessor scheduling'.

  7. Static assignment of complex stochastic tasks using stochastic majorization

    NASA Technical Reports Server (NTRS)

    Nicol, David; Simha, Rahul; Towsley, Don

    1992-01-01

    We consider the problem of statically assigning many tasks to a (smaller) system of homogeneous processors, where a task's structure is modeled as a branching process, and all tasks are assumed to have identical behavior. We show how the theory of majorization can be used to obtain a partial order among possible task assignments. Our results show that if the vector of numbers of tasks assigned to each processor under one mapping is majorized by that of another mapping, then the former mapping is better than the latter with respect to a large number of objective functions. In particular, we show how measurements of finishing time, resource utilization, and reliability are all captured by the theory. We also show how the theory may be applied to the problem of partitioning a pool of processors for distribution among parallelizable tasks.

  8. Problems on Divisibility of Binomial Coefficients

    ERIC Educational Resources Information Center

    Osler, Thomas J.; Smoak, James

    2004-01-01

    Twelve unusual problems involving divisibility of the binomial coefficients are represented in this article. The problems are listed in "The Problems" section. All twelve problems have short solutions which are listed in "The Solutions" section. These problems could be assigned to students in any course in which the binomial theorem and Pascal's…

  9. Double and multiple contacts of similar elastic materials

    NASA Astrophysics Data System (ADS)

    Sundaram, Narayan K.

    Ongoing fretting fatigue research has focussed on developing robust contact mechanics solutions for complicated load histories involving normal, shear, moment and bulk loads. For certain indenter profiles and applied loads, the contact patch separates into two disconnected regions. Existing Singular Integral Equation (SIE) techniques do not address these situations. A fast numerical tool is developed to solve such problems for similar elastic materials for a wide range of profiles and load paths including applied moments and remote bulk-stress effects. This tool is then used to investigate two problems in double contacts. The first, to determine the shear configuration space for a biquadratic punch for the generalized Cattaneo-Mindlin problem. The second, to obtain quantitative estimates of the interaction between neighboring cylindrical contacts for both the applied normal load and partial slip problems up to the limits of validity of the halfspace assumption. In double contact problems without symmetry, obtaining a unique solution requires the satisfaction of a condition relating the contact ends, rigid-body rotation and profile function. This condition has the interpretation that a rigid-rod connecting the inner contact ends of an equivalent frictionless double contact of a rigid indenter and halfspace may only undergo rigid body motions. It is also found that the ends of stick-zones, local slips and remote-applied strains in double contact problems are related by an equation expressing tangential surface-displacement continuity. This equation is essential to solve partial-slip problems without contact equivalents. Even when neighboring cylindrical contacts may be treated as non-interacting for the purpose of determining the pressure tractions, this is not generally true if a shear load is applied. The mutual influence of neighboring contacts in partial slip problems is largest at small shear load fractions. For both the pressure and partial slip problems, the interactions are stronger with increasing strength of loading and contact proximity. A new contact algorithm is developed and the SIE method extended to tackle contact problems with an arbitrary number of contact patches with no approximations made about contact interactions. In the case of multiple contact problems determining the correct contact configuration is significantly more complicated than in double contacts, necessitating a new approach. Both the normal contact and partial slip problems are solved. The tool is then used to study contacts of regular rough cylinders, a flat with rounded punch with superimposed sinusoidal roughness and is also applied to analyze the contact of an experimental rough surface with a halfspace. The partial slip results for multiple-contacts are generally consistent with Cattaneo-Mindlin continuum scale results, in that the outermost contacts tend to be in full sliding. Lastly, the influence of plasticity on frictionless multiple contact problems is studied using FEM for two common steel and aluminum alloys. The key findings are that the plasticity decreases the peak pressure and increases both real and apparent contact areas, thus 'blunting' the sharp pressures caused by the contact asperities in pure elasticity. Further, it is found that contact plasticity effects and load for onset of first yield are strongly dependent on roughness amplitude, with higher plasticity effects and lower yield-onset load at higher roughness amplitudes.

  10. An agglomerative hierarchical clustering approach to visualisation in Bayesian clustering problems

    PubMed Central

    Dawson, Kevin J.; Belkhir, Khalid

    2009-01-01

    Clustering problems (including the clustering of individuals into outcrossing populations, hybrid generations, full-sib families and selfing lines) have recently received much attention in population genetics. In these clustering problems, the parameter of interest is a partition of the set of sampled individuals, - the sample partition. In a fully Bayesian approach to clustering problems of this type, our knowledge about the sample partition is represented by a probability distribution on the space of possible sample partitions. Since the number of possible partitions grows very rapidly with the sample size, we can not visualise this probability distribution in its entirety, unless the sample is very small. As a solution to this visualisation problem, we recommend using an agglomerative hierarchical clustering algorithm, which we call the exact linkage algorithm. This algorithm is a special case of the maximin clustering algorithm that we introduced previously. The exact linkage algorithm is now implemented in our software package Partition View. The exact linkage algorithm takes the posterior co-assignment probabilities as input, and yields as output a rooted binary tree, - or more generally, a forest of such trees. Each node of this forest defines a set of individuals, and the node height is the posterior co-assignment probability of this set. This provides a useful visual representation of the uncertainty associated with the assignment of individuals to categories. It is also a useful starting point for a more detailed exploration of the posterior distribution in terms of the co-assignment probabilities. PMID:19337306

  11. Prefrontal Neurons Encode a Solution to the Credit-Assignment Problem

    PubMed Central

    Perge, János A.; Eskandar, Emad N.

    2017-01-01

    To adapt successfully to our environments, we must use the outcomes of our choices to guide future behavior. Critically, we must be able to correctly assign credit for any particular outcome to the causal features which preceded it. In some cases, the causal features may be immediately evident, whereas in others they may be separated in time or intermingled with irrelevant environmental stimuli, creating a potentially nontrivial credit-assignment problem. We examined the neuronal representation of information relevant for credit assignment in the dorsolateral prefrontal cortex (dlPFC) of two male rhesus macaques performing a task that elicited key aspects of this problem. We found that neurons conveyed the information necessary for credit assignment. Specifically, neuronal activity reflected both the relevant cues and outcomes at the time of feedback and did so in a manner that was stable over time, in contrast to prior reports of representational instability in the dlPFC. Furthermore, these representations were most stable early in learning, when credit assignment was most needed. When the same features were not needed for credit assignment, these neuronal representations were much weaker or absent. These results demonstrate that the activity of dlPFC neurons conforms to the basic requirements of a system that performs credit assignment, and that spiking activity can serve as a stable mechanism that links causes and effects. SIGNIFICANCE STATEMENT Credit assignment is the process by which we infer the causes of our successes and failures. We found that neuronal activity in the dorsolateral prefrontal cortex conveyed the necessary information for performing credit assignment. Importantly, while there are various potential mechanisms to retain a “trace” of the causal events over time, we observed that spiking activity was sufficiently stable to act as the link between causes and effects, in contrast to prior reports that suggested spiking representations were unstable over time. In addition, we observed that this stability varied as a function of learning, such that the neural code was more reliable over time during early learning, when it was most needed. PMID:28634307

  12. Distributed resource allocation under communication constraints

    NASA Astrophysics Data System (ADS)

    Dodin, Pierre; Nimier, Vincent

    2001-03-01

    This paper deals with a study of the multi-sensor management problem for multi-target tracking. The collaboration between many sensors observing the same target means that they are able to fuse their data during the information process. Then one must take into account this possibility to compute the optimal association sensors-target at each step of time. In order to solve this problem for real large scale system, one must both consider the information aspect and the control aspect of the problem. To unify these problems, one possibility is to use a decentralized filtering algorithm locally driven by an assignment algorithm. The decentralized filtering algorithm we use in our model is the filtering algorithm of Grime, which relaxes the usual full-connected hypothesis. By full-connected, one means that the information in a full-connected system is totally distributed everywhere at the same moment, which is unacceptable for a real large scale system. We modelize the distributed assignment decision with the help of a greedy algorithm. Each sensor performs a global optimization, in order to estimate other information sets. A consequence of the relaxation of the full- connected hypothesis is that the sensors' information set are not the same at each step of time, producing an information dis- symmetry in the system. The assignment algorithm uses a local knowledge of this dis-symmetry. By testing the reactions and the coherence of the local assignment decisions of our system, against maneuvering targets, we show that it is still possible to manage with decentralized assignment control even though the system is not full-connected.

  13. Multisystemic Therapy and Functional Family Therapy Compared on their Effectiveness Using the Propensity Score Method.

    PubMed

    Eeren, Hester V; Goossens, Lucas M A; Scholte, Ron H J; Busschbach, Jan J V; van der Rijken, Rachel E A

    2018-01-09

    Multisystemic Therapy (MST) and Functional Family Therapy (FFT) have overlapping target populations and treatment goals. In this study, these interventions were compared on their effectiveness using a quasi-experimental design. Between October, 2009 and June, 2014, outcome data were collected from 697 adolescents (mean age 15.3 (SD 1.48), 61.9% male) assigned to either MST or FFT (422 MST; 275 FFT). Data were gathered during Routine Outcome Monitoring. The primary outcome was externalizing problem behavior (Child Behavior Checklist and Youth Self Report). Secondary outcomes were the proportion of adolescents living at home, engaged in school or work, and who lacked police contact during treatment. Because of the non-random assignment, a propensity score method was used to control for observed pre-treatment differences. Because the risk-need-responsivity (RNR) model guided treatment assignment, effectiveness was also estimated in youth with and without a court order as an indicator of their risk level. Looking at the whole sample, no difference in effect was found with regard to externalizing problems. For adolescents without a court order, effects on externalizing problems were larger after MST. Because many more adolescents with a court order were assigned to MST compared to FFT, the propensity score method could not balance the treatment groups in this subsample. In conclusion, few differences between MST and FFT were found. In line with the RNR model, higher risk adolescents were assigned to the more intensive treatment, namely MST. In the group with lower risk adolescents, this more intensive treatment was more effective in reducing externalizing problems.

  14. Maternal education preferences moderate the effects of mandatory employment and education programs on child positive and problem behaviors.

    PubMed

    Gassman-Pines, Anna; Godfrey, Erin B; Yoshikawa, Hirokazu

    2013-01-01

    Grounded in person-environment fit theory, this study examined whether low-income mothers' preferences for education moderated the effects of employment- and education-focused welfare programs on children's positive and problem behaviors. The sample included 1,365 families with children between ages 3 and 5 years at study entry. Results 5 years after random assignment, when children were ages 8-10 years, indicated that mothers' education preferences did moderate program impacts on teacher-reported child behavior problems and positive behavior. Children whose mothers were assigned to the education program were rated by teachers to have less externalizing behavior and more positive behavior than children whose mothers were assigned to the employment program but only when mothers had strong preferences for education. © 2012 The Authors. Child Development © 2012 Society for Research in Child Development, Inc.

  15. Mining Stable Roles in RBAC

    NASA Astrophysics Data System (ADS)

    Colantonio, Alessandro; di Pietro, Roberto; Ocello, Alberto; Verde, Nino Vincenzo

    In this paper we address the problem of generating a candidate role-set for an RBAC configuration that enjoys the following two key features: it minimizes the administration cost; and, it is a stable candidate role-set. To achieve these goals, we implement a three steps methodology: first, we associate a weight to roles; second, we identify and remove the user-permission assignments that cannot belong to a role that have a weight exceeding a given threshold; third, we restrict the problem of finding a candidate role-set for the given system configuration using only the user-permission assignments that have not been removed in the second step—that is, user-permission assignments that belong to roles with a weight exceeding the given threshold. We formally show—proof of our results are rooted in graph theory—that this methodology achieves the intended goals. Finally, we discuss practical applications of our approach to the role mining problem.

  16. An automated system for reduction of the firm's employees under maximal overall efficiency

    NASA Astrophysics Data System (ADS)

    Yonchev, Yoncho; Nikolov, Simeon; Baeva, Silvia

    2012-11-01

    Achieving maximal overall efficiency is a priority in all companies. This problem is formulated as a knap-sack problem and afterwards as a linear assignment problem. An automated system is created for solving of this problem.

  17. "Ask Ernö": a self-learning tool for assignment and prediction of nuclear magnetic resonance spectra.

    PubMed

    Castillo, Andrés M; Bernal, Andrés; Dieden, Reiner; Patiny, Luc; Wist, Julien

    2016-01-01

    We present "Ask Ernö", a self-learning system for the automatic analysis of NMR spectra, consisting of integrated chemical shift assignment and prediction tools. The output of the automatic assignment component initializes and improves a database of assigned protons that is used by the chemical shift predictor. In turn, the predictions provided by the latter facilitate improvement of the assignment process. Iteration on these steps allows Ask Ernö to improve its ability to assign and predict spectra without any prior knowledge or assistance from human experts. This concept was tested by training such a system with a dataset of 2341 molecules and their (1)H-NMR spectra, and evaluating the accuracy of chemical shift predictions on a test set of 298 partially assigned molecules (2007 assigned protons). After 10 iterations, Ask Ernö was able to decrease its prediction error by 17 %, reaching an average error of 0.265 ppm. Over 60 % of the test chemical shifts were predicted within 0.2 ppm, while only 5 % still presented a prediction error of more than 1 ppm. Ask Ernö introduces an innovative approach to automatic NMR analysis that constantly learns and improves when provided with new data. Furthermore, it completely avoids the need for manually assigned spectra. This system has the potential to be turned into a fully autonomous tool able to compete with the best alternatives currently available.Graphical abstractSelf-learning loop. Any progress in the prediction (forward problem) will improve the assignment ability (reverse problem) and vice versa.

  18. The solution of target assignment problem in command and control decision-making behaviour simulation

    NASA Astrophysics Data System (ADS)

    Li, Ni; Huai, Wenqing; Wang, Shaodan

    2017-08-01

    C2 (command and control) has been understood to be a critical military component to meet an increasing demand for rapid information gathering and real-time decision-making in a dynamically changing battlefield environment. In this article, to improve a C2 behaviour model's reusability and interoperability, a behaviour modelling framework was proposed to specify a C2 model's internal modules and a set of interoperability interfaces based on the C-BML (coalition battle management language). WTA (weapon target assignment) is a typical C2 autonomous decision-making behaviour modelling problem. Different from most WTA problem descriptions, here sensors were considered to be available resources of detection and the relationship constraints between weapons and sensors were also taken into account, which brought it much closer to actual application. A modified differential evolution (MDE) algorithm was developed to solve this high-dimension optimisation problem and obtained an optimal assignment plan with high efficiency. In case study, we built a simulation system to validate the proposed C2 modelling framework and interoperability interface specification. Also, a new optimisation solution was used to solve the WTA problem efficiently and successfully.

  19. Matching School Resources and Student Needs: Scheduling and Assignment Problems in High Schools Serving At-Risk Youth. Final Report.

    ERIC Educational Resources Information Center

    Natriello, Gary; And Others

    By studying the process by which disadvantaged and low-achieving high school students are assigned to classes and special programs, how and why disadvantaged students are placed in inappropriate programs can be understood. Reasons exist to question the assumption that students are assigned to programs rationally on the basis of information about…

  20. Game theory and traffic assignment.

    DOT National Transportation Integrated Search

    2013-09-01

    Traffic assignment is used to determine the number of users on roadway links in a network. While this problem has : been widely studied in transportation literature, its use of the concept of equilibrium has attracted considerable interest : in the f...

  1. Task Assignment Heuristics for Parallel and Distributed CFD Applications

    NASA Technical Reports Server (NTRS)

    Lopez-Benitez, Noe; Djomehri, M. Jahed; Biswas, Rupak

    2003-01-01

    This paper proposes a task graph (TG) model to represent a single discrete step of multi-block overset grid computational fluid dynamics (CFD) applications. The TG model is then used to not only balance the computational workload across the overset grids but also to reduce inter-grid communication costs. We have developed a set of task assignment heuristics based on the constraints inherent in this class of CFD problems. Two basic assignments, the smallest task first (STF) and the largest task first (LTF), are first presented. They are then systematically costs. To predict the performance of the proposed task assignment heuristics, extensive performance evaluations are conducted on a synthetic TG with tasks defined in terms of the number of grid points in predetermined overlapping grids. A TG derived from a realistic problem with eight million grid points is also used as a test case.

  2. Frequency Assignments for HFDF Receivers in a Search and Rescue Network

    DTIC Science & Technology

    1990-03-01

    SAR problem where whether or not a signal is detected by RS or HFDF at the various stations is described by probabilities. Daskin assumes the...allows the problem to be formulated with a linear objective function (6:52-53). Daskin also developed a heuristic solution algorithm to solve this...en CM in o CM CM < I Q < - -.~- -^ * . . . ■ . ,■ . :ST.-.r . 5 Frequency Assignments for HFDF Receivers in a Search and

  3. Overcoming an obstacle in expanding a UMLS semantic type extent.

    PubMed

    Chen, Yan; Gu, Huanying; Perl, Yehoshua; Geller, James

    2012-02-01

    This paper strives to overcome a major problem encountered by a previous expansion methodology for discovering concepts highly likely to be missing a specific semantic type assignment in the UMLS. This methodology is the basis for an algorithm that presents the discovered concepts to a human auditor for review and possible correction. We analyzed the problem of the previous expansion methodology and discovered that it was due to an obstacle constituted by one or more concepts assigned the UMLS Semantic Network semantic type Classification. A new methodology was designed that bypasses such an obstacle without a combinatorial explosion in the number of concepts presented to the human auditor for review. The new expansion methodology with obstacle avoidance was tested with the semantic type Experimental Model of Disease and found over 500 concepts missed by the previous methodology that are in need of this semantic type assignment. Furthermore, other semantic types suffering from the same major problem were discovered, indicating that the methodology is of more general applicability. The algorithmic discovery of concepts that are likely missing a semantic type assignment is possible even in the face of obstacles, without an explosion in the number of processed concepts. Copyright © 2011 Elsevier Inc. All rights reserved.

  4. Overcoming an Obstacle in Expanding a UMLS Semantic Type Extent

    PubMed Central

    Chen, Yan; Gu, Huanying; Perl, Yehoshua; Geller, James

    2011-01-01

    This paper strives to overcome a major problem encountered by a previous expansion methodology for discovering concepts highly likely to be missing a specific semantic type assignment in the UMLS. This methodology is the basis for an algorithm that presents the discovered concepts to a human auditor for review and possible correction. We analyzed the problem of the previous expansion methodology and discovered that it was due to an obstacle constituted by one or more concepts assigned the UMLS Semantic Network semantic type Classification. A new methodology was designed that bypasses such an obstacle without a combinatorial explosion in the number of concepts presented to the human auditor for review. The new expansion methodology with obstacle avoidance was tested with the semantic type Experimental Model of Disease and found over 500 concepts missed by the previous methodology that are in need of this semantic type assignment. Furthermore, other semantic types suffering from the same major problem were discovered, indicating that the methodology is of more general applicability. The algorithmic discovery of concepts that are likely missing a semantic type assignment is possible even in the face of obstacles, without an explosion in the number of processed concepts. PMID:21925287

  5. The generalized pole assignment problem. [dynamic output feedback problems

    NASA Technical Reports Server (NTRS)

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

    1979-01-01

    Two dynamic output feedback problems for a linear, strictly proper system are considered, along with their interrelationships. The problems are formulated in the frequency domain and investigated in terms of linear equations over rings of polynomials. Necessary and sufficient conditions are expressed using genericity.

  6. Formative feedback and scaffolding for developing complex problem solving and modelling outcomes

    NASA Astrophysics Data System (ADS)

    Frank, Brian; Simper, Natalie; Kaupp, James

    2018-07-01

    This paper discusses the use and impact of formative feedback and scaffolding to develop outcomes for complex problem solving in a required first-year course in engineering design and practice at a medium-sized research-intensive Canadian university. In 2010, the course began to use team-based, complex, open-ended contextualised problems to develop problem solving, communications, teamwork, modelling, and professional skills. Since then, formative feedback has been incorporated into: task and process-level feedback on scaffolded tasks in-class, formative assignments, and post-assignment review. Development in complex problem solving and modelling has been assessed through analysis of responses from student surveys, direct criterion-referenced assessment of course outcomes from 2013 to 2015, and an external longitudinal study. The findings suggest that students are improving in outcomes related to complex problem solving over the duration of the course. Most notably, the addition of new feedback and scaffolding coincided with improved student performance.

  7. Child-Level Predictors of Responsiveness to Evidence-Based Mathematics Intervention.

    PubMed

    Powell, Sarah R; Cirino, Paul T; Malone, Amelia S

    2017-07-01

    We identified child-level predictors of responsiveness to 2 types of mathematics (calculation and word-problem) intervention among 2nd-grade children with mathematics difficulty. Participants were 250 children in 107 classrooms in 23 schools pretested on mathematics and general cognitive measures and posttested on mathematics measures. We assigned classrooms randomly assigned to calculation intervention, word-problem intervention, or business-as-usual control. Intervention lasted 17 weeks. Path analyses indicated that scores on working memory and language comprehension assessments moderated responsiveness to calculation intervention. No moderators were identified for responsiveness to word-problem intervention. Across both intervention groups and the control group, attentive behavior predicted both outcomes. Initial calculation skill predicted the calculation outcome, and initial language comprehension predicted word-problem outcomes. These results indicate that screening for calculation intervention should include a focus on working memory, language comprehension, attentive behavior, and calculations. Screening for word-problem intervention should focus on attentive behavior and word problems.

  8. 29 CFR 785.37 - Home to work on special one-day assignment in another city.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 3 2011-07-01 2011-07-01 false Home to work on special one-day assignment in another city... another city. A problem arises when an employee who regularly works at a fixed location in one city is given a special 1-day work assignment in another city. For example, an employee who works in Washington...

  9. 29 CFR 785.37 - Home to work on special one-day assignment in another city.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Home to work on special one-day assignment in another city... another city. A problem arises when an employee who regularly works at a fixed location in one city is given a special 1-day work assignment in another city. For example, an employee who works in Washington...

  10. Spectrum-to-Spectrum Searching Using a Proteome-wide Spectral Library*

    PubMed Central

    Yen, Chia-Yu; Houel, Stephane; Ahn, Natalie G.; Old, William M.

    2011-01-01

    The unambiguous assignment of tandem mass spectra (MS/MS) to peptide sequences remains a key unsolved problem in proteomics. Spectral library search strategies have emerged as a promising alternative for peptide identification, in which MS/MS spectra are directly compared against a reference library of confidently assigned spectra. Two problems relate to library size. First, reference spectral libraries are limited to rediscovery of previously identified peptides and are not applicable to new peptides, because of their incomplete coverage of the human proteome. Second, problems arise when searching a spectral library the size of the entire human proteome. We observed that traditional dot product scoring methods do not scale well with spectral library size, showing reduction in sensitivity when library size is increased. We show that this problem can be addressed by optimizing scoring metrics for spectrum-to-spectrum searches with large spectral libraries. MS/MS spectra for the 1.3 million predicted tryptic peptides in the human proteome are simulated using a kinetic fragmentation model (MassAnalyzer version2.1) to create a proteome-wide simulated spectral library. Searches of the simulated library increase MS/MS assignments by 24% compared with Mascot, when using probabilistic and rank based scoring methods. The proteome-wide coverage of the simulated library leads to 11% increase in unique peptide assignments, compared with parallel searches of a reference spectral library. Further improvement is attained when reference spectra and simulated spectra are combined into a hybrid spectral library, yielding 52% increased MS/MS assignments compared with Mascot searches. Our study demonstrates the advantages of using probabilistic and rank based scores to improve performance of spectrum-to-spectrum search strategies. PMID:21532008

  11. A group-based tasks allocation algorithm for the optimization of long leave opportunities in academic departments

    NASA Astrophysics Data System (ADS)

    Eyono Obono, S. D.; Basak, Sujit Kumar

    2011-12-01

    The general formulation of the assignment problem consists in the optimal allocation of a given set of tasks to a workforce. This problem is covered by existing literature for different domains such as distributed databases, distributed systems, transportation, packets radio networks, IT outsourcing, and teaching allocation. This paper presents a new version of the assignment problem for the allocation of academic tasks to staff members in departments with long leave opportunities. It presents the description of a workload allocation scheme and its algorithm, for the allocation of an equitable number of tasks in academic departments where long leaves are necessary.

  12. Encouraging Sixth-Grade Students' Problem-Solving Performance by Teaching through Problem Solving

    ERIC Educational Resources Information Center

    Bostic, Jonathan D.; Pape, Stephen J.; Jacobbe, Tim

    2016-01-01

    This teaching experiment provided students with continuous engagement in a problem-solving based instructional approach during one mathematics unit. Three sections of sixth-grade mathematics were sampled from a school in Florida, U.S.A. and one section was randomly assigned to experience teaching through problem solving. Students' problem-solving…

  13. Preference in Random Assignment: Implications for the Interpretation of Randomized Trials

    PubMed Central

    Gold, Paul B.; Hargreaves, William A.; Aronson, Elliot; Bickman, Leonard; Barreira, Paul J.; Jones, Danson R.; Rodican, Charles F.; Fisher, William H.

    2009-01-01

    Random assignment to a preferred experimental condition can increase service engagement and enhance outcomes, while assignment to a less-preferred condition can discourage service receipt and limit outcome attainment. We examined randomized trials for one prominent psychiatric rehabilitation intervention, supported employment, to gauge how often assignment preference might have complicated the interpretation of findings. Condition descriptions, and greater early attrition from services-as-usual comparison conditions, suggest that many study enrollees favored assignment to new rapid-job-placement supported employment, but no study took this possibility into account. Reviews of trials in other service fields are needed to determine whether this design problem is widespread. PMID:19434489

  14. Assigning Oxidation States to Some Metal Dioxygen Complexes of Biological Interest.

    ERIC Educational Resources Information Center

    Summerville, David A.; And Others

    1979-01-01

    The bonding of dioxygen in metal-dioxygen complexes is discussed, paying particular attention to the problems encountered in assigning conventional oxidation numbers to both the metal center and coordinated dioxygen. Complexes of iron, cobalt, chromium, and manganese are considered. (BB)

  15. College Students' Preferences for Psychotherapy across Depression, Anxiety, Relationship, and Academic Problems

    ERIC Educational Resources Information Center

    Joyce, Aaron W.; Ross, Michael J.; Vander Wal, Jillon S.; Austin, Chammie C.

    2009-01-01

    The present study examined differences in college students' preferences for processes of change across four kinds of problems: academic, relationship, depression, and anxiety. Two hundred eighteen undergraduates were randomly assigned to complete either an academic problems, relationship problems, depression, or anxiety Processes of Change…

  16. Interleaved Practice Improves Mathematics Learning

    ERIC Educational Resources Information Center

    Rohrer, Doug; Dedrick, Robert F.; Stershic, Sandra

    2015-01-01

    A typical mathematics assignment consists primarily of practice problems requiring the strategy introduced in the immediately preceding lesson (e.g., a dozen problems that are solved by using the Pythagorean theorem). This means that students know which strategy is needed to solve each problem before they read the problem. In an alternative…

  17. Effect of the strong coupling on the exchange bias field in IrMn/Py/Ru/Co spin valves

    NASA Astrophysics Data System (ADS)

    Tarazona, H. S.; Alayo, W.; Landauro, C. V.; Quispe-Marcatoma, J.

    2018-01-01

    The IrMn/Py/Ru/Co (Py = Ni81Fe19) spin valves have been produced by sputtering deposition and analyzed by magnetization measurements and a theoretical modelling of their exchange interactions, based on the macro-spin model. The Ru thickness was grown between 6 and 22 Å, which is small enough to promote strong indirect coupling between Py and Co. Results of measurements showed a large and gradual change in the shape of hysteresis loops when the Ru thickness was varied. The theoretical analysis, using numerical calculations based on the gradient conjugate method, provides the exchange coupling constants (bilinear and biquadratic), the exchange anisotropy fields and the magnetic anisotropy fields (uniaxial and rotatable). The exchange bias fields of spin valves were compared to that of a IrMn/Py bilayer. We found that the difference between these fields oscillates with Ru thickness in the same manner as the bilinear coupling constants.

  18. Dynamic phase transitions and dynamic phase diagrams of the Blume-Emery-Griffiths model in an oscillating field: the effective-field theory based on the Glauber-type stochastic dynamics

    NASA Astrophysics Data System (ADS)

    Ertaş, Mehmet; Keskin, Mustafa

    2015-06-01

    Using the effective-field theory based on the Glauber-type stochastic dynamics (DEFT), we investigate dynamic phase transitions and dynamic phase diagrams of the Blume-Emery-Griffiths model under an oscillating magnetic field. We presented the dynamic phase diagrams in (T/J, h0/J), (D/J, T/J) and (K/J, T/J) planes, where T, h0, D, K and z are the temperature, magnetic field amplitude, crystal-field interaction, biquadratic interaction and the coordination number. The dynamic phase diagrams exhibit several ordered phases, coexistence phase regions and special critical points, as well as re-entrant behavior depending on interaction parameters. We also compare and discuss the results with the results of the same system within the mean-field theory based on the Glauber-type stochastic dynamics and find that some of the dynamic first-order phase lines and special dynamic critical points disappeared in the DEFT calculation.

  19. Spin-flop coupling and exchange anisotropy in ferromagnetic/antiferromagnetic bilayers

    NASA Astrophysics Data System (ADS)

    Xu, Xiao-Yong; Hu, Jing-Guo

    2009-03-01

    By investigating the antiferromagnetic spin configuration, the exchange anisotropy and the interfacial spin-flop coupling in ferromagnetic/antiferromagnetic (FM/AF) bilayers have been discussed in detail. The results show that there are four possible cases for the AF spins, namely the reversible recovering case, irreversible half-rotating case, irreversible reversing and irreversible half-reversing cases. Moreover, the realization of the cases strongly depends on interface quadratic coupling, interface spin-flop (biquadratic) coupling and AF thickness. The magnetic phase diagram in terms of the AF thickness tAF, the interfacial bilinear coupling J1 and the spin-flop coupling J2 has been constructed. The corresponding critical parameters in which the exchange bias will occur or approach saturation have been also presented. Specially, the small spin-flop exchange coupling may result in an exchange bias without the interfacial bilinear exchange coupling. However, in general, the spin-flop exchange coupling can weaken or eliminate the exchange bias, but always enhances the coercivity greatly.

  20. Assessment of Thematic Mapper Band-to-band Registration by the Block Correlation Method

    NASA Technical Reports Server (NTRS)

    Card, D. H.; Wrigley, R. C.; Mertz, F. C.; Hall, J. R.

    1984-01-01

    The design of the Thematic Mapper (TM) multispectral radiometer makes it susceptible to band-to-band misregistration. To estimate band-to-band misregistration a block correlation method is employed. This method is chosen over other possible techniques (band differencing and flickering) because quantitative results are produced. The method correlates rectangular blocks of pixels from one band against blocks centered on identical pixels from a second band. The block pairs are shifted in pixel increments both vertically and horizontally with respect to each other and the correlation coefficient for each shift position is computed. The displacement corresponding to the maximum correlation is taken as the best estimate of registration error for each block pair. Subpixel shifts are estimated by a bi-quadratic interpolation of the correlation values surrounding the maximum correlation. To obtain statistical summaries for each band combination post processing of the block correlation results performed. The method results in estimates of registration error that are consistent with expectations.

  1. Binary Bees Algorithm - bioinspiration from the foraging mechanism of honeybees to optimize a multiobjective multidimensional assignment problem

    NASA Astrophysics Data System (ADS)

    Xu, Shuo; Ji, Ze; Truong Pham, Duc; Yu, Fan

    2011-11-01

    The simultaneous mission assignment and home allocation for hospital service robots studied is a Multidimensional Assignment Problem (MAP) with multiobjectives and multiconstraints. A population-based metaheuristic, the Binary Bees Algorithm (BBA), is proposed to optimize this NP-hard problem. Inspired by the foraging mechanism of honeybees, the BBA's most important feature is an explicit functional partitioning between global search and local search for exploration and exploitation, respectively. Its key parts consist of adaptive global search, three-step elitism selection (constraint handling, non-dominated solutions selection, and diversity preservation), and elites-centred local search within a Hamming neighbourhood. Two comparative experiments were conducted to investigate its single objective optimization, optimization effectiveness (indexed by the S-metric and C-metric) and optimization efficiency (indexed by computational burden and CPU time) in detail. The BBA outperformed its competitors in almost all the quantitative indices. Hence, the above overall scheme, and particularly the searching history-adapted global search strategy was validated.

  2. GCSE Assessment Notes: Six GCSE Assessment Assignments.

    ERIC Educational Resources Information Center

    Graham, Stephen

    1988-01-01

    Provided are copy masters, instructions for use, and grading criteria for six problems used as part of the practical assessment for a modular science course. Each problem gives a narrative and a list of materials necessary to complete the problem. (CW)

  3. Real life working shift assignment problem

    NASA Astrophysics Data System (ADS)

    Sze, San-Nah; Kwek, Yeek-Ling; Tiong, Wei-King; Chiew, Kang-Leng

    2017-07-01

    This study concerns about the working shift assignment in an outlet of Supermarket X in Eastern Mall, Kuching. The working shift assignment needs to be solved at least once in every month. Current approval process of working shifts is too troublesome and time-consuming. Furthermore, the management staff cannot have an overview of manpower and working shift schedule. Thus, the aim of this study is to develop working shift assignment simulation and propose a working shift assignment solution. The main objective for this study is to fulfill manpower demand at minimum operation cost. Besides, the day off and meal break policy should be fulfilled accordingly. Demand based heuristic is proposed to assign working shift and the quality of the solution is evaluated by using the real data.

  4. Measuring Human Performance on Clustering Problems: Some Potential Objective Criteria and Experimental Research Opportunities

    ERIC Educational Resources Information Center

    Brusco, Michael J.

    2007-01-01

    The study of human performance on discrete optimization problems has a considerable history that spans various disciplines. The two most widely studied problems are the Euclidean traveling salesperson problem and the quadratic assignment problem. The purpose of this paper is to outline a program of study for the measurement of human performance on…

  5. An investigation of the use of temporal decomposition in space mission scheduling

    NASA Technical Reports Server (NTRS)

    Bullington, Stanley E.; Narayanan, Venkat

    1994-01-01

    This research involves an examination of techniques for solving scheduling problems in long-duration space missions. The mission timeline is broken up into several time segments, which are then scheduled incrementally. Three methods are presented for identifying the activities that are to be attempted within these segments. The first method is a mathematical model, which is presented primarily to illustrate the structure of the temporal decomposition problem. Since the mathematical model is bound to be computationally prohibitive for realistic problems, two heuristic assignment procedures are also presented. The first heuristic method is based on dispatching rules for activity selection, and the second heuristic assigns performances of a model evenly over timeline segments. These heuristics are tested using a sample Space Station mission and a Spacelab mission. The results are compared with those obtained by scheduling the missions without any problem decomposition. The applicability of this approach to large-scale mission scheduling problems is also discussed.

  6. Parallel, Asynchronous Executive (PAX): System concepts, facilities, and architecture

    NASA Technical Reports Server (NTRS)

    Jones, W. H.

    1983-01-01

    The Parallel, Asynchronous Executive (PAX) is a software operating system simulation that allows many computers to work on a single problem at the same time. PAX is currently implemented on a UNIVAC 1100/42 computer system. Independent UNIVAC runstreams are used to simulate independent computers. Data are shared among independent UNIVAC runstreams through shared mass-storage files. PAX has achieved the following: (1) applied several computing processes simultaneously to a single, logically unified problem; (2) resolved most parallel processor conflicts by careful work assignment; (3) resolved by means of worker requests to PAX all conflicts not resolved by work assignment; (4) provided fault isolation and recovery mechanisms to meet the problems of an actual parallel, asynchronous processing machine. Additionally, one real-life problem has been constructed for the PAX environment. This is CASPER, a collection of aerodynamic and structural dynamic problem simulation routines. CASPER is not discussed in this report except to provide examples of parallel-processing techniques.

  7. MILP model for integrated balancing and sequencing mixed-model two-sided assembly line with variable launching interval and assignment restrictions

    NASA Astrophysics Data System (ADS)

    Azmi, N. I. L. Mohd; Ahmad, R.; Zainuddin, Z. M.

    2017-09-01

    This research explores the Mixed-Model Two-Sided Assembly Line (MMTSAL). There are two interrelated problems in MMTSAL which are line balancing and model sequencing. In previous studies, many researchers considered these problems separately and only few studied them simultaneously for one-sided line. However in this study, these two problems are solved simultaneously to obtain more efficient solution. The Mixed Integer Linear Programming (MILP) model with objectives of minimizing total utility work and idle time is generated by considering variable launching interval and assignment restriction constraint. The problem is analysed using small-size test cases to validate the integrated model. Throughout this paper, numerical experiment was conducted by using General Algebraic Modelling System (GAMS) with the solver CPLEX. Experimental results indicate that integrating the problems of model sequencing and line balancing help to minimise the proposed objectives function.

  8. NVR-BIP: Nuclear Vector Replacement using Binary Integer Programming for NMR Structure-Based Assignments.

    PubMed

    Apaydin, Mehmet Serkan; Çatay, Bülent; Patrick, Nicholas; Donald, Bruce R

    2011-05-01

    Nuclear magnetic resonance (NMR) spectroscopy is an important experimental technique that allows one to study protein structure and dynamics in solution. An important bottleneck in NMR protein structure determination is the assignment of NMR peaks to the corresponding nuclei. Structure-based assignment (SBA) aims to solve this problem with the help of a template protein which is homologous to the target and has applications in the study of structure-activity relationship, protein-protein and protein-ligand interactions. We formulate SBA as a linear assignment problem with additional nuclear overhauser effect constraints, which can be solved within nuclear vector replacement's (NVR) framework (Langmead, C., Yan, A., Lilien, R., Wang, L. and Donald, B. (2003) A Polynomial-Time Nuclear Vector Replacement Algorithm for Automated NMR Resonance Assignments. Proc. the 7th Annual Int. Conf. Research in Computational Molecular Biology (RECOMB) , Berlin, Germany, April 10-13, pp. 176-187. ACM Press, New York, NY. J. Comp. Bio. , (2004), 11, pp. 277-298; Langmead, C. and Donald, B. (2004) An expectation/maximization nuclear vector replacement algorithm for automated NMR resonance assignments. J. Biomol. NMR , 29, 111-138). Our approach uses NVR's scoring function and data types and also gives the option of using CH and NH residual dipolar coupling (RDCs), instead of NH RDCs which NVR requires. We test our technique on NVR's data set as well as on four new proteins. Our results are comparable to NVR's assignment accuracy on NVR's test set, but higher on novel proteins. Our approach allows partial assignments. It is also complete and can return the optimum as well as near-optimum assignments. Furthermore, it allows us to analyze the information content of each data type and is easily extendable to accept new forms of input data, such as additional RDCs.

  9. The use of writing assignments to help students synthesize content in upper-level undergraduate biology courses.

    PubMed

    Sparks-Thissen, Rebecca L

    2017-02-01

    Biology education is undergoing a transformation toward a more student-centered, inquiry-driven classroom. Many educators have designed engaging assignments that are designed to help undergraduate students gain exposure to the scientific process and data analysis. One of these types of assignments is use of a grant proposal assignment. Many instructors have used these assignments in lecture-based courses to help students process information in the literature and apply that information to a novel problem such as design of an antiviral drug or a vaccine. These assignments have been helpful in engaging students in the scientific process in the absence of an inquiry-driven laboratory. This commentary discusses the application of these grant proposal writing assignments to undergraduate biology courses. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. Ecologically-Based Family Therapy Outcome with Substance Abusing Runaway Adolescents

    PubMed Central

    Slesnick, Natasha; Prestopnik, Jillian L.

    2007-01-01

    Runaway youth report a broader range and higher severity of substance-related, mental health and family problems relative to non-runaway youth. Most studies to date have collected self-report data on the family and social history; virtually no research has examined treatment effectiveness with this population. This study is a treatment development project in which 124 runaway youth were randomly assigned to 1) Ecologically-Based Family Therapy (EBFT) or 2) Service as Usual (SAU) through a shelter. Youth completed an intake, posttreatment, 6 and 12 month follow-up assessment. Youth assigned to EBFT reported greater reductions in overall substance abuse compared to youth assigned to SAU while other problem areas improved in both conditions. Findings suggest that EBFT is an efficacious intervention for this relatively severe population of youth. PMID:15878048

  11. Using sound to solve syntactic problems: the role of phonology in grammatical category assignments.

    PubMed

    Kelly, M H

    1992-04-01

    One ubiquitous problem in language processing involves the assignment of words to the correct grammatical category, such as noun or verb. In general, semantic and syntactic cues have been cited as the principal information for grammatical category assignment, to the neglect of possible phonological cues. This neglect is unwarranted, and the following claims are made: (a) Numerous correlations between phonology and grammatical class exist, (b) some of these correlations are large and can pervade the entire lexicon of a language and hence can involve thousands of words, (c) experiments have repeatedly found that adults and children have learned these correlations, and (d) explanations for how these correlations arose can be proposed and evaluated. Implications of these phenomena for language representation and processing are discussed.

  12. Problem Solution Project: Transforming Curriculum and Empowering Urban Students and Teachers

    ERIC Educational Resources Information Center

    Jarrett, Olga S.; Stenhouse, Vera

    2011-01-01

    This article presents findings of 6 years of implementing a Problem Solution Project, an assignment influenced by service learning, problem-based learning, critical theory, and critical pedagogy whereby teachers help children tackle real problems. Projects of 135 teachers in an urban certification/master's program were summarized by cohort year…

  13. Optimal UAS Assignments and Trajectories for Persistent Surveillance and Data Collection from a Wireless Sensor Network

    DTIC Science & Technology

    2015-12-24

    minimizing a weighted sum ofthe time and control effort needed to collect sensor data. This problem formulation is a modified traveling salesman ...29 2.5 The Shortest Path Problem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 2.5.1 Traveling Salesman Problem ...48 3.3.1 Initial Guess by Traveling Salesman Problem Solution

  14. American Viticultural Areas: A Problem in Regional Geography.

    ERIC Educational Resources Information Center

    Macdonald, Gerald M.; Lemaire, Denyse

    1995-01-01

    Maintains that growing grapes for winemaking has increased dramatically in the United States. Describes a college class assignment in which students analyzed climate and soil type to identify appropriate viticulture areas. Reports high student interest in the assignment and includes four figures illustrating the approach. (CFR)

  15. Motion Planning and Task Assignment for Unmanned Aerial Vehicles Cooperating with Unattended Ground Sensors

    DTIC Science & Technology

    2014-10-24

    problem was formalized as the Dubins travelling salesman problem (TSP). In the second phase of the research we have...given constraints on its motion. This problem was formalized as the Dubins travelling salesman problem (TSP). The contributions of the study in the... problem was formalized as the Dubins travelling salesman problem (TSP). The Dubins Travelling Salesperson Problem (DTSP) and its variants [8, 12,

  16. PROBABILISTIC CROSS-IDENTIFICATION IN CROWDED FIELDS AS AN ASSIGNMENT PROBLEM

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

    Budavári, Tamás; Basu, Amitabh, E-mail: budavari@jhu.edu, E-mail: basu.amitabh@jhu.edu

    2016-10-01

    One of the outstanding challenges of cross-identification is multiplicity: detections in crowded regions of the sky are often linked to more than one candidate associations of similar likelihoods. We map the resulting maximum likelihood partitioning to the fundamental assignment problem of discrete mathematics and efficiently solve the two-way catalog-level matching in the realm of combinatorial optimization using the so-called Hungarian algorithm. We introduce the method, demonstrate its performance in a mock universe where the true associations are known, and discuss the applicability of the new procedure to large surveys.

  17. NASA Astrophysics Data System (ADS)

    2018-05-01

    Eigenvalues and eigenvectors, together, constitute the eigenstructure of the system. The design of vibrating systems aimed at satisfying specifications on eigenvalues and eigenvectors, which is commonly known as eigenstructure assignment, has drawn increasing interest over the recent years. The most natural mathematical framework for such problems is constituted by the inverse eigenproblems, which consist in the determination of the system model that features a desired set of eigenvalues and eigenvectors. Although such a problem is intrinsically challenging, several solutions have been proposed in the literature. The approaches to eigenstructure assignment can be basically divided into passive control and active control.

  18. Probabilistic Cross-identification in Crowded Fields as an Assignment Problem

    NASA Astrophysics Data System (ADS)

    Budavári, Tamás; Basu, Amitabh

    2016-10-01

    One of the outstanding challenges of cross-identification is multiplicity: detections in crowded regions of the sky are often linked to more than one candidate associations of similar likelihoods. We map the resulting maximum likelihood partitioning to the fundamental assignment problem of discrete mathematics and efficiently solve the two-way catalog-level matching in the realm of combinatorial optimization using the so-called Hungarian algorithm. We introduce the method, demonstrate its performance in a mock universe where the true associations are known, and discuss the applicability of the new procedure to large surveys.

  19. Complete virilization in congenital adrenal hyperplasia: clinical course, medical management and disease-related complications.

    PubMed

    Woelfle, J; Hoepffner, W; Sippell, W G; Brämswig, J H; Heidemann, P; Deiss, D; Bökenkamp, A; Roth, C; Irle, U; Wollmann, H A; Zachmann, M; Kubini, K; Albers, N

    2002-02-01

    In girls with congenital adrenal hyperplasia (CAH), genital ambiguity usually leads to a rapid neonatal diagnosis. Rarely, CAH causes complete virilization and male sex assignment with a delayed diagnosis. After being confronted with very specific problems in two of such patients, we collected data of patients with CAH and complete virilization in a nationwide study to delineate specific problems of these rare patients in order to improve their management. Through the German Working Group of Paediatric Endocrinology (Arbeitsgemeinschaft Pädiatrische Endokrinologie, APE), questionnaires were sent to all members caring for patients with CAH and complete virilization in their endocrine clinics. Data from 16 patients from 10 paediatric endocrine centres were assessed by questionnaire. The following problems have been encountered. (1) Sex assignment/gender identity: initially all patients had a male sex assignment. Six patients were diagnosed during the first month of life. Five were reassigned to female sex immediately, one at the age of 19 months. Except in one girl demonstrating some tomboyish behaviour, gender role behaviour in these patients did not differ from unaffected girls. Ten patients were diagnosed late at 3.4--7 years of age. In seven patients with a late diagnosis, male sex assignment was maintained; one of them expressed some concerns about living as a male. In three patients late sex reversal was performed, gender identity is very poor in one and new sex assignment is currently under consideration. (2) SURGERY: irrespective of the sex assigned, all patients had between one and three surgical procedures, including clitoris reduction and (repeated) vaginoplasties in patients with female sex assignment. Hysterectomy and ovarectomy were performed in patients with male sex assignment. (3) Short stature: patients with a late diagnosis of CAH had extremely advanced bone ages of +6.3 to +9.5 years, leading to severely reduced final height of 137 to 150 cm in adult patients. Patients tended to follow height percentiles of genetic females. One pubertal patient was suicidal due to short stature. (4) Central precocious puberty (CPP): prolonged exposition to adrenal androgens led to CPP in one patient. He was treated with GnRH analogues until gonadectomy. Patients with CAH and complete virilization have a high risk of being diagnosed late. There are major problems and uncertainties of the patients' families and the treating physicians concerning gender assignment. Gender identity is disturbed in some patients. In addition, multiple surgical procedures are necessary and short stature as well as central precocious puberty might be important to avoid late sequelae. While some surgical interventions are probably unavoidable, most of these issues could be resolved with an early diagnosis. Thus, especially for these patients, a neonatal screening programme for CAH would be of paramount importance.

  20. Do emergency medical services dispatch nature and severity codes agree with paramedic field findings?

    PubMed

    Neely, K W; Eldurkar, J A; Drake, M E

    2000-02-01

    Emergency medical services (EMS) systems increasingly seek to triage patients to alternative EMS resources. Emergency medical services dispatchers may be asked to perform this triage. New protocols may be necessary. Alternatively, existing protocols may be sufficient for this task. For an existing dispatch protocol to be sufficient, it at least must accurately categorize patient condition and severity based on an external standard. To examine the extent to which nature codes (NCs), or patient condition codes, and severity codes (SCs) currently assigned in one urban 911 center agree with paramedic field findings. The null hypothesis was that there is no routine agreement (75%) between dispatcher-assigned NC or SC and paramedic-assigned NC or SC for the same patient using the same protocol. Emergency medical services dispatch nature and severity code data and matching out-of-hospital data were prospectively gathered over six months. Dispatch data included the NC: caller-identified problem, and the SC: dispatcher-assessed severity. Each NC is modified by one of three SCs (1, 3, or 9): 1 is emergent, 3 is urgent, and 9 is neither. Paramedics verified and/or corrected dispatcher-assigned NCs and SCs using the same dispatch protocol. One thousand forty usable cases fell into 33 unique NC/SC combinations. The designation of SC 1 was assigned 275 times, SC 3 was assigned 736 times, and SC 9 was assigned 24 times. The SC was missing five times. The overall NC agreement was 0.70 (95% CI = 0.697 to 0.703). The overall SC agreement was 0.65 (95% CI = 0.645 to 0.655). The NC agreement exceeded 75% for ten (59%) NC/SC combinations. The SC agreement exceeded 75% for five (29%) NC/SC combinations. There was both NC and SC agreement for four (24%) combinations: urgent breathing problems, urgent diabetic problems, urgent falls, and urgent overdoses. The greatest NC/SC disagreement occurred within emergent and urgent traffic crashes. Paramedics adjusted SC toward lower severity 29% of the time and toward higher severity 5.4% of the time. There was no upward SC adjustment for eight (47%) combinations. Certain dispatcher-assigned NC and SC codes and NC/SC combinations achieved the study threshold. Overall agreement failed to achieve the threshold. The lowest SC level was rarely assigned, preventing a meaningful analysis of all severity levels.

  1. Three geographic decomposition approaches in transportation network analysis

    DOT National Transportation Integrated Search

    1980-03-01

    This document describes the results of research into the application of geographic decomposition techniques to practical transportation network problems. Three approaches are described for the solution of the traffic assignment problem. One approach ...

  2. Application of Decomposition to Transportation Network Analysis

    DOT National Transportation Integrated Search

    1976-10-01

    This document reports preliminary results of five potential applications of the decomposition techniques from mathematical programming to transportation network problems. The five application areas are (1) the traffic assignment problem with fixed de...

  3. Accelerated Math®. Primary Mathematics. What Works Clearinghouse Intervention Report

    ERIC Educational Resources Information Center

    What Works Clearinghouse, 2017

    2017-01-01

    "Accelerated Math®," published by Renaissance Learning, is a software tool that provides practice problems for students in grades K-12 and provides teachers with reports to monitor student progress. "Accelerated Math®" creates individualized student assignments, scores the assignments, and generates reports on student progress.…

  4. (Explain It) x 3

    ERIC Educational Resources Information Center

    McGuire, Linda

    2014-01-01

    This article will describe a writing assignment designed for use in a liberal arts college whose mission stresses effective written communication both within and across disciplines. In this assignment, students write three separate solutions to the same mathematics problem: one for a mathematical peer, a second for a contemporary that does not…

  5. Using Portfolio Assignments to Assess Students' Mathematical Thinking

    ERIC Educational Resources Information Center

    Fukawa-Connelly, Timothy; Buck, Stephen

    2010-01-01

    Writing in mathematics can improve procedural knowledge and communication skills and may also help students better understand and then remember problems. The majority of mathematics teachers know that they ought to include some writing assignments in their instructional plans, but the challenge of covering the curriculum and the time required to…

  6. Student's Lab Assignments in PDE Course with MAPLE.

    ERIC Educational Resources Information Center

    Ponidi, B. Alhadi

    Computer-aided software has been used intensively in many mathematics courses, especially in computational subjects, to solve initial value and boundary value problems in Partial Differential Equations (PDE). Many software packages were used in student lab assignments such as FORTRAN, PASCAL, MATLAB, MATHEMATICA, and MAPLE in order to accelerate…

  7. Listener Reliability in Assigning Utterance Boundaries in Children's Spontaneous Speech

    ERIC Educational Resources Information Center

    Stockman, Ida J.

    2010-01-01

    Research and clinical practices often rely on an utterance unit for spoken language analysis. This paper calls attention to the problems encountered when identifying utterance boundaries in young children's spontaneous conversational speech. The results of a reliability study of utterance boundary assignment are described for 20 females with…

  8. Distributed Collaborative Homework Activities in a Problem-Based Usability Engineering Course

    ERIC Educational Resources Information Center

    Carroll, John M.; Jiang, Hao; Borge, Marcela

    2015-01-01

    Teams of students in an upper-division undergraduate Usability Engineering course used a collaborative environment to carry out a series of three distributed collaborative homework assignments. Assignments were case-based analyses structured using a jigsaw design; students were provided a collaborative software environment and introduced to a…

  9. Increasing Student-Learning Team Effectiveness with Team Charters

    ERIC Educational Resources Information Center

    Hunsaker, Phillip; Pavett, Cynthia; Hunsaker, Johanna

    2011-01-01

    Because teams are a ubiquitous part of most organizations today, it is common for business educators to use team assignments to help students experientially learn about course concepts and team process. Unfortunately, students frequently experience a number of problems during team assignments. The authors describe the results of their research and…

  10. Teaching Case: A Systems Analysis Role-Play Exercise and Assignment

    ERIC Educational Resources Information Center

    Mitri, Michel; Cole, Carey; Atkins, Laura

    2017-01-01

    This paper presents a role-play exercise and assignment that provides an active learning experience related to the system investigation phase of an SDLC. Whether using waterfall or agile approaches, the first SDLC step usually involves system investigation activities, including problem identification, feasibility study, cost-benefit analysis, and…

  11. 38 CFR 21.198 - “Discontinued” status.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... personal or other problems; or (ii) Inability of the veteran to benefit from rehabilitation services... of entitlement. (4) Medical and related problems. A veteran's case will be discontinued and assigned... program because of a serious physical or emotional problem for an extended period; and (ii) VA medical...

  12. 38 CFR 21.198 - “Discontinued” status.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... personal or other problems; or (ii) Inability of the veteran to benefit from rehabilitation services... of entitlement. (4) Medical and related problems. A veteran's case will be discontinued and assigned... program because of a serious physical or emotional problem for an extended period; and (ii) VA medical...

  13. Separation anxiety among birth-assigned male children in a specialty gender identity service.

    PubMed

    VanderLaan, Doug P; Santarossa, Alanna; Nabbijohn, A Natisha; Wood, Hayley; Owen-Anderson, Allison; Zucker, Kenneth J

    2018-01-01

    Previous research suggested that separation anxiety disorder (SAD) is overrepresented among birth-assigned male children clinic-referred for gender dysphoria (GD). The present study examined maternally reported separation anxiety of birth-assigned male children assessed in a specialty gender identity service (N = 360). SAD was determined in relation to DSM-III and DSM-IV criteria, respectively. A dimensional metric of separation anxiety was examined in relation to several additional factors: age, ethnicity, parental marital status and social class, IQ, gender nonconformity, behavioral and emotional problems, and poor peer relations. When defined in a liberal fashion, 55.8% were classified as having SAD. When using a more conservative criterion, 5.3% were classified as having SAD, which was significantly greater than the estimated general population prevalence for boys, but not for girls. Dimensionally, separation anxiety was associated with having parents who were not married or cohabitating as well as with elevations in gender nonconformity; however, the association with gender nonconformity was no longer significant when statistically controlling for internalizing problems. Thus, SAD appears to be common among birth-assigned males clinic-referred for GD when defined in a liberal fashion, and more common than in boys, but not girls, from the general population even when more stringent criteria were applied. Also, the degree of separation anxiety appears to be linked to generic risk factors (i.e., parental marital status, internalizing problems). As such, although separation anxiety is common among birth-assigned male children clinic-referred for GD, it seems unlikely to hold unique significance for this population based on the current data.

  14. Multi-topic assignment for exploratory navigation of consumer health information in NetWellness using formal concept analysis.

    PubMed

    Cui, Licong; Xu, Rong; Luo, Zhihui; Wentz, Susan; Scarberry, Kyle; Zhang, Guo-Qiang

    2014-08-03

    Finding quality consumer health information online can effectively bring important public health benefits to the general population. It can empower people with timely and current knowledge for managing their health and promoting wellbeing. Despite a popular belief that search engines such as Google can solve all information access problems, recent studies show that using search engines and simple search terms is not sufficient. Our objective is to provide an approach to organizing consumer health information for navigational exploration, complementing keyword-based direct search. Multi-topic assignment to health information, such as online questions, is a fundamental step for navigational exploration. We introduce a new multi-topic assignment method combining semantic annotation using UMLS concepts (CUIs) and Formal Concept Analysis (FCA). Each question was tagged with CUIs identified by MetaMap. The CUIs were filtered with term-frequency and a new term-strength index to construct a CUI-question context. The CUI-question context and a topic-subject context were used for multi-topic assignment, resulting in a topic-question context. The topic-question context was then directly used for constructing a prototype navigational exploration interface. Experimental evaluation was performed on the task of automatic multi-topic assignment of 99 predefined topics for about 60,000 consumer health questions from NetWellness. Using example-based metrics, suitable for multi-topic assignment problems, our method achieved a precision of 0.849, recall of 0.774, and F₁ measure of 0.782, using a reference standard of 278 questions with manually assigned topics. Compared to NetWellness' original topic assignment, a 36.5% increase in recall is achieved with virtually no sacrifice in precision. Enhancing the recall of multi-topic assignment without sacrificing precision is a prerequisite for achieving the benefits of navigational exploration. Our new multi-topic assignment method, combining term-strength, FCA, and information retrieval techniques, significantly improved recall and performed well according to example-based metrics.

  15. Multi-topic assignment for exploratory navigation of consumer health information in NetWellness using formal concept analysis

    PubMed Central

    2014-01-01

    Background Finding quality consumer health information online can effectively bring important public health benefits to the general population. It can empower people with timely and current knowledge for managing their health and promoting wellbeing. Despite a popular belief that search engines such as Google can solve all information access problems, recent studies show that using search engines and simple search terms is not sufficient. Our objective is to provide an approach to organizing consumer health information for navigational exploration, complementing keyword-based direct search. Multi-topic assignment to health information, such as online questions, is a fundamental step for navigational exploration. Methods We introduce a new multi-topic assignment method combining semantic annotation using UMLS concepts (CUIs) and Formal Concept Analysis (FCA). Each question was tagged with CUIs identified by MetaMap. The CUIs were filtered with term-frequency and a new term-strength index to construct a CUI-question context. The CUI-question context and a topic-subject context were used for multi-topic assignment, resulting in a topic-question context. The topic-question context was then directly used for constructing a prototype navigational exploration interface. Results Experimental evaluation was performed on the task of automatic multi-topic assignment of 99 predefined topics for about 60,000 consumer health questions from NetWellness. Using example-based metrics, suitable for multi-topic assignment problems, our method achieved a precision of 0.849, recall of 0.774, and F1 measure of 0.782, using a reference standard of 278 questions with manually assigned topics. Compared to NetWellness’ original topic assignment, a 36.5% increase in recall is achieved with virtually no sacrifice in precision. Conclusion Enhancing the recall of multi-topic assignment without sacrificing precision is a prerequisite for achieving the benefits of navigational exploration. Our new multi-topic assignment method, combining term-strength, FCA, and information retrieval techniques, significantly improved recall and performed well according to example-based metrics. PMID:25086916

  16. Examining the Preparatory Effects of Problem Generation and Solution Generation on Learning from Instruction

    ERIC Educational Resources Information Center

    Kapur, Manu

    2018-01-01

    The goal of this paper is to isolate the preparatory effects of problem-generation from solution generation in problem-posing contexts, and their underlying mechanisms on learning from instruction. Using a randomized-controlled design, students were assigned to one of two conditions: (a) problem-posing with solution generation, where they…

  17. Introduction of a Population Balance Based Design Problem in a Particle Science and Technology Course for Chemical Engineers

    ERIC Educational Resources Information Center

    Ehrman, Sheryl H.; Castellanos, Patricia; Dwivedi, Vivek; Diemer, R. Bertrum

    2007-01-01

    A particle technology design problem incorporating population balance modeling was developed and assigned to senior and first-year graduate students in a Particle Science and Technology course. The problem focused on particle collection, with a pipeline agglomerator, Cyclone, and baghouse comprising the collection system. The problem was developed…

  18. Investigating the Effect of Complexity Factors in Stoichiometry Problems Using Logistic Regression and Eye Tracking

    ERIC Educational Resources Information Center

    Tang, Hui; Kirk, John; Pienta, Norbert J.

    2014-01-01

    This paper includes two experiments, one investigating complexity factors in stoichiometry word problems, and the other identifying students' problem-solving protocols by using eye-tracking technology. The word problems used in this study had five different complexity factors, which were randomly assigned by a Web-based tool that we developed. The…

  19. Exploiting Elementary Landscapes for TSP, Vehicle Routing and Scheduling

    DTIC Science & Technology

    2015-09-03

    Traveling Salesman Problem (TSP) and Graph Coloring are elementary. Problems such as MAX-kSAT are a superposition of k elementary landscapes. This...search space. Problems such as the Traveling Salesman Problem (TSP), Graph Coloring, the Frequency Assignment Problem , as well as Min-Cut and Max-Cut...echoing our earlier esults on the Traveling Salesman Problem . Using two locally optimal solutions as “parent” solutions, we have developed a

  20. Capacity-constrained traffic assignment in networks with residual queues

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

    Lam, W.H.K.; Zhang, Y.

    2000-04-01

    This paper proposes a capacity-constrained traffic assignment model for strategic transport planning in which the steady-state user equilibrium principle is extended for road networks with residual queues. Therefore, the road-exit capacity and the queuing effects can be incorporated into the strategic transport model for traffic forecasting. The proposed model is applicable to the congested network particularly when the traffic demands exceeds the capacity of the network during the peak period. An efficient solution method is proposed for solving the steady-state traffic assignment problem with residual queues. Then a simple numerical example is employed to demonstrate the application of the proposedmore » model and solution method, while an example of a medium-sized arterial highway network in Sioux Falls, South Dakota, is used to test the applicability of the proposed solution to real problems.« less

  1. A Markov Random Field Framework for Protein Side-Chain Resonance Assignment

    NASA Astrophysics Data System (ADS)

    Zeng, Jianyang; Zhou, Pei; Donald, Bruce Randall

    Nuclear magnetic resonance (NMR) spectroscopy plays a critical role in structural genomics, and serves as a primary tool for determining protein structures, dynamics and interactions in physiologically-relevant solution conditions. The current speed of protein structure determination via NMR is limited by the lengthy time required in resonance assignment, which maps spectral peaks to specific atoms and residues in the primary sequence. Although numerous algorithms have been developed to address the backbone resonance assignment problem [68,2,10,37,14,64,1,31,60], little work has been done to automate side-chain resonance assignment [43, 48, 5]. Most previous attempts in assigning side-chain resonances depend on a set of NMR experiments that record through-bond interactions with side-chain protons for each residue. Unfortunately, these NMR experiments have low sensitivity and limited performance on large proteins, which makes it difficult to obtain enough side-chain resonance assignments. On the other hand, it is essential to obtain almost all of the side-chain resonance assignments as a prerequisite for high-resolution structure determination. To overcome this deficiency, we present a novel side-chain resonance assignment algorithm based on alternative NMR experiments measuring through-space interactions between protons in the protein, which also provide crucial distance restraints and are normally required in high-resolution structure determination. We cast the side-chain resonance assignment problem into a Markov Random Field (MRF) framework, and extend and apply combinatorial protein design algorithms to compute the optimal solution that best interprets the NMR data. Our MRF framework captures the contact map information of the protein derived from NMR spectra, and exploits the structural information available from the backbone conformations determined by orientational restraints and a set of discretized side-chain conformations (i.e., rotamers). A Hausdorff-based computation is employed in the scoring function to evaluate the probability of side-chain resonance assignments to generate the observed NMR spectra. The complexity of the assignment problem is first reduced by using a dead-end elimination (DEE) algorithm, which prunes side-chain resonance assignments that are provably not part of the optimal solution. Then an A* search algorithm is used to find a set of optimal side-chain resonance assignments that best fit the NMR data. We have tested our algorithm on NMR data for five proteins, including the FF Domain 2 of human transcription elongation factor CA150 (FF2), the B1 domain of Protein G (GB1), human ubiquitin, the ubiquitin-binding zinc finger domain of the human Y-family DNA polymerase Eta (pol η UBZ), and the human Set2-Rpb1 interacting domain (hSRI). Our algorithm assigns resonances for more than 90% of the protons in the proteins, and achieves about 80% correct side-chain resonance assignments. The final structures computed using distance restraints resulting from the set of assigned side-chain resonances have backbone RMSD 0.5 - 1.4 Å and all-heavy-atom RMSD 1.0 - 2.2 Å from the reference structures that were determined by X-ray crystallography or traditional NMR approaches. These results demonstrate that our algorithm can be successfully applied to automate side-chain resonance assignment and high-quality protein structure determination. Since our algorithm does not require any specific NMR experiments for measuring the through-bond interactions with side-chain protons, it can save a significant amount of both experimental cost and spectrometer time, and hence accelerate the NMR structure determination process.

  2. How did you guess? Or, what do multiple-choice questions measure?

    PubMed

    Cox, K R

    1976-06-05

    Multiple-choice questions classified as requiring problem-solving skills have been interpreted as measuring problem-solving skills within students, with the implicit hypothesis that questions needing an increasingly complex intellectual process should present increasing difficulty to the student. This hypothesis was tested in a 150-question paper taken by 721 students in seven Australian medical schools. No correlation was observed between difficulty and assigned process. Consequently, the question-answering process was explored with a group of final-year students. Anecdotal recall by students gave heavy weight to knowledge rather than problem solving in answering these questions. Assignment of the 150 questions to the classification by three teachers and six students showed their congruence to be a little above random probability.

  3. Integrated optimization of location assignment and sequencing in multi-shuttle automated storage and retrieval systems under modified 2n-command cycle pattern

    NASA Astrophysics Data System (ADS)

    Yang, Peng; Peng, Yongfei; Ye, Bin; Miao, Lixin

    2017-09-01

    This article explores the integrated optimization problem of location assignment and sequencing in multi-shuttle automated storage/retrieval systems under the modified 2n-command cycle pattern. The decision of storage and retrieval (S/R) location assignment and S/R request sequencing are jointly considered. An integer quadratic programming model is formulated to describe this integrated optimization problem. The optimal travel cycles for multi-shuttle S/R machines can be obtained to process S/R requests in the storage and retrieval request order lists by solving the model. The small-sized instances are optimally solved using CPLEX. For large-sized problems, two tabu search algorithms are proposed, in which the first come, first served and nearest neighbour are used to generate initial solutions. Various numerical experiments are conducted to examine the heuristics' performance and the sensitivity of algorithm parameters. Furthermore, the experimental results are analysed from the viewpoint of practical application, and a parameter list for applying the proposed heuristics is recommended under different real-life scenarios.

  4. Maximization of Learning Speed Due to Neuronal Redundancy in Reinforcement Learning

    NASA Astrophysics Data System (ADS)

    Takiyama, Ken

    2016-11-01

    Adaptable neural activity contributes to the flexibility of human behavior, which is optimized in situations such as motor learning and decision making. Although learning signals in motor learning and decision making are low-dimensional, neural activity, which is very high dimensional, must be modified to achieve optimal performance based on the low-dimensional signal, resulting in a severe credit-assignment problem. Despite this problem, the human brain contains a vast number of neurons, leaving an open question: what is the functional significance of the huge number of neurons? Here, I address this question by analyzing a redundant neural network with a reinforcement-learning algorithm in which the numbers of neurons and output units are N and M, respectively. Because many combinations of neural activity can generate the same output under the condition of N ≫ M, I refer to the index N - M as neuronal redundancy. Although greater neuronal redundancy makes the credit-assignment problem more severe, I demonstrate that a greater degree of neuronal redundancy facilitates learning speed. Thus, in an apparent contradiction of the credit-assignment problem, I propose the hypothesis that a functional role of a huge number of neurons or a huge degree of neuronal redundancy is to facilitate learning speed.

  5. From Rags to Riches

    ERIC Educational Resources Information Center

    Sweet, Colleen

    2008-01-01

    In this article, the author presents the "Rags to Riches" design project she introduced to her students. She assigned each of her students one item from an array to thrift store goods which included old scarves, sweaters, jackets, and even evening gowns. The design problem was to imagine what a clothing tag might look like if the assigned item…

  6. ELECTRICAL AND ELECTRONIC INDUSTRIAL CONTROL. D-C MAGNETIC MOTOR CONTROL, UNIT 7, ASSIGNMENTS.

    ERIC Educational Resources Information Center

    SUTTON, MACK C.

    THIS GUIDE IS FOR INDIVIDUAL STUDENT USE IN STUDYING DIRECT CURRENT MAGNETIC MOTOR CONTROL IN ELECTRICAL-ELECTRONIC PROGRAMS. IT WAS DEVELOPED BY AN INSTRUCTIONAL MATERIALS SPECIALIST AND ADVISERS. EACH OF THE 15 ASSIGNMENT SHEETS PROVIDES THE LESSON SUBJECT, PURPOSE, INTRODUCTORY INFORMATION, STUDY REFERENCES, AND PROBLEMS. SOME OF THE LESSONS…

  7. Lights, Camera, Action! Learning about Management with Student-Produced Video Assignments

    ERIC Educational Resources Information Center

    Schultz, Patrick L.; Quinn, Andrew S.

    2014-01-01

    In this article, we present a proposal for fostering learning in the management classroom through the use of student-produced video assignments. We describe the potential for video technology to create active learning environments focused on problem solving, authentic and direct experiences, and interaction and collaboration to promote student…

  8. Turnaround Time and Market Capacity in Contract Cheating

    ERIC Educational Resources Information Center

    Wallace, Melisa J.; Newton, Philip M.

    2014-01-01

    Contract cheating is the process whereby students auction off the opportunity for others to complete assignments for them. It is an apparently widespread yet under-researched problem. One suggested strategy to prevent contract cheating is to shorten the turnaround time between the release of assignment details and the submission date, thus making…

  9. "Yes, a T-Shirt!": Assessing Visual Composition in the "Writing" Class

    ERIC Educational Resources Information Center

    Odell, Lee; Katz, Susan M.

    2009-01-01

    Computer technology is expanding our profession's conception of composing, allowing visual information to play a substantial role in an increasing variety of composition assignments. This expansion, however, creates a major problem: How does one assess student work on these assignments? Current work in assessment provides only partial answers to…

  10. Solving multiconstraint assignment problems using learning automata.

    PubMed

    Horn, Geir; Oommen, B John

    2010-02-01

    This paper considers the NP-hard problem of object assignment with respect to multiple constraints: assigning a set of elements (or objects) into mutually exclusive classes (or groups), where the elements which are "similar" to each other are hopefully located in the same class. The literature reports solutions in which the similarity constraint consists of a single index that is inappropriate for the type of multiconstraint problems considered here and where the constraints could simultaneously be contradictory. This feature, where we permit possibly contradictory constraints, distinguishes this paper from the state of the art. Indeed, we are aware of no learning automata (or other heuristic) solutions which solve this problem in its most general setting. Such a scenario is illustrated with the static mapping problem, which consists of distributing the processes of a parallel application onto a set of computing nodes. This is a classical and yet very important problem within the areas of parallel computing, grid computing, and cloud computing. We have developed four learning-automata (LA)-based algorithms to solve this problem: First, a fixed-structure stochastic automata algorithm is presented, where the processes try to form pairs to go onto the same node. This algorithm solves the problem, although it requires some centralized coordination. As it is desirable to avoid centralized control, we subsequently present three different variable-structure stochastic automata (VSSA) algorithms, which have superior partitioning properties in certain settings, although they forfeit some of the scalability features of the fixed-structure algorithm. All three VSSA algorithms model the processes as automata having first the hosting nodes as possible actions; second, the processes as possible actions; and, third, attempting to estimate the process communication digraph prior to probabilistically mapping the processes. This paper, which, we believe, comprehensively reports the pioneering LA solutions to this problem, unequivocally demonstrates that LA can play an important role in solving complex combinatorial and integer optimization problems.

  11. Optimal Assignment Problem Applications of Finite Mathematics to Business and Economics. [and] Difference Equations with Applications. Applications of Difference Equations to Economics and Social Sciences. [and] Selected Applications of Mathematics to Finance and Investment. Applications of Elementary Algebra to Finance. [and] Force of Interest. Applications of Calculus to Finance. UMAP Units 317, 322, 381, 382.

    ERIC Educational Resources Information Center

    Gale, David; And Others

    Four units make up the contents of this document. The first examines applications of finite mathematics to business and economies. The user is expected to learn the method of optimization in optimal assignment problems. The second module presents applications of difference equations to economics and social sciences, and shows how to: 1) interpret…

  12. An Effective Evolutionary Approach for Bicriteria Shortest Path Routing Problems

    NASA Astrophysics Data System (ADS)

    Lin, Lin; Gen, Mitsuo

    Routing problem is one of the important research issues in communication network fields. In this paper, we consider a bicriteria shortest path routing (bSPR) model dedicated to calculating nondominated paths for (1) the minimum total cost and (2) the minimum transmission delay. To solve this bSPR problem, we propose a new multiobjective genetic algorithm (moGA): (1) an efficient chromosome representation using the priority-based encoding method; (2) a new operator of GA parameters auto-tuning, which is adaptively regulation of exploration and exploitation based on the change of the average fitness of parents and offspring which is occurred at each generation; and (3) an interactive adaptive-weight fitness assignment mechanism is implemented that assigns weights to each objective and combines the weighted objectives into a single objective function. Numerical experiments with various scales of network design problems show the effectiveness and the efficiency of our approach by comparing with the recent researches.

  13. The unassigned distance geometry problem

    DOE PAGES

    Duxbury, P. M.; Granlund, L.; Gujarathi, S. R.; ...

    2015-11-19

    Studies of distance geometry problems (DGP) have focused on cases where the vertices at the ends of all or most of the given distances are known or assigned, which we call assigned distance geometry problems (aDGPs). In this contribution we consider the unassigned distance geometry problem (uDGP) where the vertices associated with a given distance are unknown, so the graph structure has to be discovered. uDGPs arises when attempting to find the atomic structure of molecules and nanoparticles using X-ray or neutron diffraction data from non-crystalline materials. Rigidity theory provides a useful foundation for both aDGPs and uDGPs, though itmore » is restricted to generic realizations of graphs, and key results are summarized. Conditions for unique realization are discussed for aDGP and uDGP cases, build-up algorithms for both cases are described and experimental results for uDGP are presented.« less

  14. Characterizing the Fundamental Intellectual Steps Required in the Solution of Conceptual Problems

    NASA Astrophysics Data System (ADS)

    Stewart, John

    2010-02-01

    At some level, the performance of a science class must depend on what is taught, the information content of the materials and assignments of the course. The introductory calculus-based electricity and magnetism class at the University of Arkansas is examined using a catalog of the basic reasoning steps involved in the solution of problems assigned in the class. This catalog was developed by sampling popular physics textbooks for conceptual problems. The solution to each conceptual problem was decomposed into its fundamental reasoning steps. These fundamental steps are, then, used to quantify the distribution of conceptual content within the course. Using this characterization technique, an exceptionally detailed picture of the information flow and structure of the class can be produced. The intellectual structure of published conceptual inventories is compared with the information presented in the class and the dependence of conceptual performance on the details of coverage extracted. )

  15. A heterogeneous fleet vehicle routing model for solving the LPG distribution problem: A case study

    NASA Astrophysics Data System (ADS)

    Onut, S.; Kamber, M. R.; Altay, G.

    2014-03-01

    Vehicle Routing Problem (VRP) is an important management problem in the field of distribution and logistics. In VRPs, routes from a distribution point to geographically distributed points are designed with minimum cost and considering customer demands. All points should be visited only once and by one vehicle in one route. Total demand in one route should not exceed the capacity of the vehicle that assigned to that route. VRPs are varied due to real life constraints related to vehicle types, number of depots, transportation conditions and time periods, etc. Heterogeneous fleet vehicle routing problem is a kind of VRP that vehicles have different capacity and costs. There are two types of vehicles in our problem. In this study, it is used the real world data and obtained from a company that operates in LPG sector in Turkey. An optimization model is established for planning daily routes and assigned vehicles. The model is solved by GAMS and optimal solution is found in a reasonable time.

  16. Interlocked Problem Posing and Children's Problem Posing Performance in Free Structured Situations

    ERIC Educational Resources Information Center

    Cankoy, Osman

    2014-01-01

    The aim of this study is to explore the mathematical problem posing performance of students in free structured situations. Two classes of fifth grade students (N = 30) were randomly assigned to experimental and control groups. The categories of the problems posed in free structured situations by the 2 groups of students were studied through…

  17. The Benefit of Interleaved Mathematics Practice Is Not Limited to Superficially Similar Kinds of Problems

    ERIC Educational Resources Information Center

    Rohrer, Doug; Dedrick, Robert F.; Burgess, Kaleena

    2014-01-01

    Most mathematics assignments consist of a group of problems requiring the same strategy. For example, a lesson on the quadratic formula is typically followed by a block of problems requiring students to use the quadratic formula, which means that students know the appropriate strategy before they read each problem. In an alternative approach,…

  18. Self-Administered Vidoetape Therapy for Families With Conduct-Problem Children: Comparison With Two Cost-Effective Treatments and a Control Group.

    ERIC Educational Resources Information Center

    Webster-Stratton, Carolyn; And Others

    1988-01-01

    Assigned parents of 114 conduct-problem young children to either individually administered videotape modeling treatment, group discussion videotape modeling treatment, group discussion treatment, or waiting-list control. Compared with controls, all three treatment groups of mothers reported significantly fewer child behavior problems, more…

  19. Interpersonal Problem-Solving Skills Training in the Treatment of Self-Poisoning Patients.

    ERIC Educational Resources Information Center

    McLeavey, B. C.; And Others

    1994-01-01

    Evaluated the effectiveness of interpersonal problem-solving skills training (IPSST) for the treatment of self-poisoning patients. Subjects were assigned randomly either to IPSST or to a control treatment. Although both treatments reduced the number of presenting problems, the IPSST was more effective as determined by other outcome measures. (RJM)

  20. The Effect of Contextual and Conceptual Rewording on Mathematical Problem-Solving Performance

    ERIC Educational Resources Information Center

    Haghverdi, Majid; Wiest, Lynda R.

    2016-01-01

    This study shows how separate and combined contextual and conceptual problem rewording can positively influence student performance in solving mathematical word problems. Participants included 80 seventh-grade Iranian students randomly assigned in groups of 20 to three experimental groups involving three types of rewording and a control group. All…

  1. Student-Created Homework Problems Based on YouTube Videos

    ERIC Educational Resources Information Center

    Liberatore, Matthew W.; Marr, David W. M.; Herring, Andrew M.; Way, J. Douglas

    2013-01-01

    Inspired by YouTube videos, students created homework problems as part of a class project. The project has been successful at different parts of the semester and demonstrated learning of course concepts. These new problems were implemented both in class and as part of homework assignments without significant changes. Examples from a material and…

  2. A New Algorithm to Create Balanced Teams Promoting More Diversity

    ERIC Educational Resources Information Center

    Dias, Teresa Galvão; Borges, José

    2017-01-01

    The problem of assigning students to teams can be described as maximising their profiles diversity within teams while minimising the differences among teams. This problem is commonly known as the maximally diverse grouping problem and it is usually formulated as maximising the sum of the pairwise distances among students within teams. We propose…

  3. Effect of a "Look-Ahead" Problem on Undergraduate Engineering Students' Concept Comprehension

    ERIC Educational Resources Information Center

    Goodman, Kevin; Davis, Julian; McDonald, Thomas

    2016-01-01

    In an effort to motivate undergraduate engineering students to prepare for class by reviewing material before lectures, a "Look-Ahead" problem was utilized. Students from two undergraduate engineering courses; Statics and Electronic Circuits, were assigned problems from course material that had not yet been covered in class. These…

  4. Improving the efficiency of branch-and-bound complete-search NMR assignment using the symmetry of molecules and spectra

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

    Bernal, Andrés; Patiny, Luc; Castillo, Andrés M.

    2015-02-21

    Nuclear magnetic resonance (NMR) assignment of small molecules is presented as a typical example of a combinatorial optimization problem in chemical physics. Three strategies that help improve the efficiency of solution search by the branch and bound method are presented: 1. reduction of the size of the solution space by resort to a condensed structure formula, wherein symmetric nuclei are grouped together; 2. partitioning of the solution space based on symmetry, that becomes the basis for an efficient branching procedure; and 3. a criterion of selection of input restrictions that leads to increased gaps between branches and thus faster pruningmore » of non-viable solutions. Although the examples chosen to illustrate this work focus on small-molecule NMR assignment, the results are generic and might help solving other combinatorial optimization problems.« less

  5. Global crop production forecasting: An analysis of the data system problems and their solutions

    NASA Technical Reports Server (NTRS)

    Neiers, J.; Graf, H.

    1978-01-01

    Data related problems in the acquisition and use of satellite data necessary for operational forecasting of global crop production are considered for the purpose of establishing a measurable baseline. For data acquisition the world was divided into 37 crop regions in 22 countries. These regions represent approximately 95 percent of the total world production of the selected crops of interest, i.e., wheat, corn, soybeans, and rice. Targets were assigned to each region. Limited time periods during which data could be taken (windows) were assigned to each target. Each target was assigned to a cloud region. The DSDS was used to measure the success of obtaining data for each target during the specified windows for the regional cloud conditions and the specific alternatives being analyzed. The results of this study suggest several approaches for an operational system that will perform satisfactorily with two LANDSAT type satellites.

  6. Storage assignment optimization in a multi-tier shuttle warehousing system

    NASA Astrophysics Data System (ADS)

    Wang, Yanyan; Mou, Shandong; Wu, Yaohua

    2016-03-01

    The current mathematical models for the storage assignment problem are generally established based on the traveling salesman problem(TSP), which has been widely applied in the conventional automated storage and retrieval system(AS/RS). However, the previous mathematical models in conventional AS/RS do not match multi-tier shuttle warehousing systems(MSWS) because the characteristics of parallel retrieval in multiple tiers and progressive vertical movement destroy the foundation of TSP. In this study, a two-stage open queuing network model in which shuttles and a lift are regarded as servers at different stages is proposed to analyze system performance in the terms of shuttle waiting period (SWP) and lift idle period (LIP) during transaction cycle time. A mean arrival time difference matrix for pairwise stock keeping units(SKUs) is presented to determine the mean waiting time and queue length to optimize the storage assignment problem on the basis of SKU correlation. The decomposition method is applied to analyze the interactions among outbound task time, SWP, and LIP. The ant colony clustering algorithm is designed to determine storage partitions using clustering items. In addition, goods are assigned for storage according to the rearranging permutation and the combination of storage partitions in a 2D plane. This combination is derived based on the analysis results of the queuing network model and on three basic principles. The storage assignment method and its entire optimization algorithm method as applied in a MSWS are verified through a practical engineering project conducted in the tobacco industry. The applying results show that the total SWP and LIP can be reduced effectively to improve the utilization rates of all devices and to increase the throughput of the distribution center.

  7. Tenderfooting: Tackling the Problems of Freshman Writers.

    ERIC Educational Resources Information Center

    Hobbs, Valerie; Rex-Kerish, Lesley

    1986-01-01

    University of California writing instructors must teach poorly prepared freshmen how to survive English classes and how to adapt the skills they learn to the rest of their university writing assignments. Reading, thinking, organizing, and stylistic problems are discussed. (MLW)

  8. Propagation of Disturbances in Traffic Flow

    DOT National Transportation Integrated Search

    1977-09-01

    The system-optimized static traffic-assignment problem in a freeway corridor network is the problem of choosing a distribution of vehicles in the network to minimize average travel time. It is of interest to know how sensitive the optimal steady-stat...

  9. Pedagogy of the logic model: teaching undergraduates to work together to change their communities.

    PubMed

    Zimmerman, Lindsey; Kamal, Zohra; Kim, Hannah

    2013-01-01

    Undergraduate community psychology courses can empower students to address challenging problems in their local communities. Creating a logic model is an experiential way to learn course concepts by "doing." Throughout the semester, students work with peers to define a problem, develop an intervention, and plan an evaluation focused on an issue of concern to them. This report provides an overview of how to organize a community psychology course around the creation of a logic model in order for students to develop this applied skill. Two undergraduate student authors report on their experience with the logic model assignment, describing the community problem they chose to address, what they learned from the assignment, what they found challenging, and what they are doing now in their communities based on what they learned.

  10. Text Summarization Model based on Facility Location Problem

    NASA Astrophysics Data System (ADS)

    Takamura, Hiroya; Okumura, Manabu

    e propose a novel multi-document generic summarization model based on the budgeted median problem, which is a facility location problem. The summarization method based on our model is an extractive method, which selects sentences from the given document cluster and generates a summary. Each sentence in the document cluster will be assigned to one of the selected sentences, where the former sentece is supposed to be represented by the latter. Our method selects sentences to generate a summary that yields a good sentence assignment and hence covers the whole content of the document cluster. An advantage of this method is that it can incorporate asymmetric relations between sentences such as textual entailment. Through experiments, we showed that the proposed method yields good summaries on the dataset of DUC'04.

  11. Navigating complex decision spaces: Problems and paradigms in sequential choice

    PubMed Central

    Walsh, Matthew M.; Anderson, John R.

    2015-01-01

    To behave adaptively, we must learn from the consequences of our actions. Doing so is difficult when the consequences of an action follow a delay. This introduces the problem of temporal credit assignment. When feedback follows a sequence of decisions, how should the individual assign credit to the intermediate actions that comprise the sequence? Research in reinforcement learning provides two general solutions to this problem: model-free reinforcement learning and model-based reinforcement learning. In this review, we examine connections between stimulus-response and cognitive learning theories, habitual and goal-directed control, and model-free and model-based reinforcement learning. We then consider a range of problems related to temporal credit assignment. These include second-order conditioning and secondary reinforcers, latent learning and detour behavior, partially observable Markov decision processes, actions with distributed outcomes, and hierarchical learning. We ask whether humans and animals, when faced with these problems, behave in a manner consistent with reinforcement learning techniques. Throughout, we seek to identify neural substrates of model-free and model-based reinforcement learning. The former class of techniques is understood in terms of the neurotransmitter dopamine and its effects in the basal ganglia. The latter is understood in terms of a distributed network of regions including the prefrontal cortex, medial temporal lobes cerebellum, and basal ganglia. Not only do reinforcement learning techniques have a natural interpretation in terms of human and animal behavior, but they also provide a useful framework for understanding neural reward valuation and action selection. PMID:23834192

  12. Error Checking and Graphical Representation of Multiple–Complete–Digest (MCD) Restriction-Fragment Maps

    PubMed Central

    Thayer, Edward C.; Olson, Maynard V.; Karp, Richard M.

    1999-01-01

    Genetic and physical maps display the relative positions of objects or markers occurring within a target DNA molecule. In constructing maps, the primary objective is to determine the ordering of these objects. A further objective is to assign a coordinate to each object, indicating its distance from a reference end of the target molecule. This paper describes a computational method and a body of software for assigning coordinates to map objects, given a solution or partial solution to the ordering problem. We describe our method in the context of multiple–complete–digest (MCD) mapping, but it should be applicable to a variety of other mapping problems. Because of errors in the data or insufficient clone coverage to uniquely identify the true ordering of the map objects, a partial ordering is typically the best one can hope for. Once a partial ordering has been established, one often seeks to overlay a metric along the map to assess the distances between the map objects. This problem often proves intractable because of data errors such as erroneous local length measurements (e.g., large clone lengths on low-resolution physical maps). We present a solution to the coordinate assignment problem for MCD restriction-fragment mapping, in which a coordinated set of single-enzyme restriction maps are simultaneously constructed. We show that the coordinate assignment problem can be expressed as the solution of a system of linear constraints. If the linear system is free of inconsistencies, it can be solved using the standard Bellman–Ford algorithm. In the more typical case where the system is inconsistent, our program perturbs it to find a new consistent system of linear constraints, close to those of the given inconsistent system, using a modified Bellman–Ford algorithm. Examples are provided of simple map inconsistencies and the methods by which our program detects candidate data errors and directs the user to potential suspect regions of the map. PMID:9927487

  13. Minimizing distortion and internal forces in truss structures by simulated annealing

    NASA Technical Reports Server (NTRS)

    Kincaid, Rex K.

    1989-01-01

    Inaccuracies in the length of members and the diameters of joints of large truss reflector backup structures may produce unacceptable levels of surface distortion and member forces. However, if the member lengths and joint diameters can be measured accurately it is possible to configure the members and joints so that root-mean-square (rms) surface error and/or rms member forces is minimized. Following Greene and Haftka (1989) it is assumed that the force vector f is linearly proportional to the member length errors e(sub M) of dimension NMEMB (the number of members) and joint errors e(sub J) of dimension NJOINT (the number of joints), and that the best-fit displacement vector d is a linear function of f. Let NNODES denote the number of positions on the surface of the truss where error influences are measured. The solution of the problem is discussed. To classify, this problem was compared to a similar combinatorial optimization problem. In particular, when only the member length errors are considered, minimizing d(sup 2)(sub rms) is equivalent to the quadratic assignment problem. The quadratic assignment problem is a well known NP-complete problem in operations research literature. Hence minimizing d(sup 2)(sub rms) is is also an NP-complete problem. The focus of the research is the development of a simulated annealing algorithm to reduce d(sup 2)(sub rms). The plausibility of this technique is its recent success on a variety of NP-complete combinatorial optimization problems including the quadratic assignment problem. A physical analogy for simulated annealing is the way liquids freeze and crystallize. All computational experiments were done on a MicroVAX. The two interchange heuristic is very fast but produces widely varying results. The two and three interchange heuristic provides less variability in the final objective function values but runs much more slowly. Simulated annealing produced the best objective function values for every starting configuration and was faster than the two and three interchange heuristic.

  14. Secrets to Writing Great Papers. The Study Smart Series.

    ERIC Educational Resources Information Center

    Kesselman-Turkel, Judi; Peterson, Franklynn

    This book explains how to work with ideas to hone them into words, providing techniques and exercises for brainstorming, choosing the right approach, working with an unknown or boring assigned topic, and selecting the best point of view. It presents 10 steps, noting related problems: (1) "Decide on Size" (no specific length is assigned);…

  15. Integrating Global Learning into a Psychology Course Using an Online Platform

    ERIC Educational Resources Information Center

    Forden, Carie L.; Carrillo, Amy M.

    2014-01-01

    There is a demand for the integration of global learning/diversity across the curriculum. A series of cross-cultural assignments was created to facilitate global learning in two social psychology classes, one in Egypt, and one in the USA. In these assignments, students collected data and applied course concepts to real-life problems, then…

  16. Persistence in Expatriate Academic Assignments in the United Arab Emirates: A Case Study

    ERIC Educational Resources Information Center

    Ryan, Gerard D.

    2012-01-01

    This study explored factors that influenced persistence in expatriate academic assignments in the United Arab Emirates (UAE). Specifically, the problem that was addressed was an investigation of the reasons why some expatriate academics declared their intent to leave an academic position within one year of arrival while others choose to extend…

  17. Commander, U.S. Pacific Fleet

    Science.gov Websites

    Us SAN DIEGO (May 22, 2018) Sailors assigned to Coastal Riverine Squadron (CRS) 3 operate a Mark VI patrol boat during a final evaluation problem conducted by Coastal Riverine Group (CRG) 1's training and ./Released) Sailors assigned to Coastal Riverine Squadron 3 operate a Mark VI patrol boat in waters off San

  18. Gamification for Non-Majors Mathematics: An Innovative Assignment Model

    ERIC Educational Resources Information Center

    Leong, Siow Hoo; Tang, Howe Eng

    2017-01-01

    The most important ingredient of the pedagogy for teaching non-majors is getting their engagement. This paper proposes to use gamification to engage non-majors. An innovative game termed as Cover the Hungarian's Zeros is designed to tackle the common weakness of non-majors mathematics in solving the assignment problem using the Hungarian Method.…

  19. Weblogs in Teacher Education Internships: Promoting Reflection and Self-Efficacy While Reducing Stress?

    ERIC Educational Resources Information Center

    Petko, Dominik; Egger, Nives; Cantieni, Andrea

    2017-01-01

    The study examines the use of weblogs in teacher education internships and its impact on student stress levels, self-efficacy, and reflective abilities. One hundred and seventy-six student teachers were randomly assigned to five groups. Four groups used weblogs (a) with emotion-focused or with problem-focused writing assignments in combination (b)…

  20. Personal Reflection: Reflections on a Family Health History Assignment for Undergraduate Public Health and Nursing Students

    ERIC Educational Resources Information Center

    Rooks, Ronica N.; Ford, Cassandra

    2013-01-01

    This personal reflection describes our experiences with incorporating the scholarship of teaching and learning and problem-based techniques to facilitate undergraduate student learning and their professional development in the health sciences. We created a family health history assignment to discuss key concepts in our courses, such as health…

  1. Selections from the ABC 2014 Annual Convention, Philadelphia, Pennsylvania A Well-Stitched Banner of Favorite Assignments: Leadership and Other-Focused Communication and Projects

    ERIC Educational Resources Information Center

    Whalen, D. Joel

    2015-01-01

    This article, the second of a two-part series, features 11 teaching innovations presented at the 2014 Association for Business Communication annual conference. These 11 assignments included leadership and other-focused communication--detecting communication style, adaptive communication, personality type, delivering feedback, problem solving, and…

  2. Principals' Approaches to Cultivating Teacher Effectiveness: Constraints and Opportunities in Hiring, Assigning, Evaluating, and Developing Teachers

    ERIC Educational Resources Information Center

    Donaldson, Morgaen L.

    2013-01-01

    Purpose: How principals hire, assign, evaluate, and provide growth opportunities to teachers likely have major ramifications for teacher effectiveness and student learning. This article reports on the barriers principals encountered when carrying out these functions and variations in the degree to which they identified obstacles and problem-solved…

  3. Connected Component Model for Multi-Object Tracking.

    PubMed

    He, Zhenyu; Li, Xin; You, Xinge; Tao, Dacheng; Tang, Yuan Yan

    2016-08-01

    In multi-object tracking, it is critical to explore the data associations by exploiting the temporal information from a sequence of frames rather than the information from the adjacent two frames. Since straightforwardly obtaining data associations from multi-frames is an NP-hard multi-dimensional assignment (MDA) problem, most existing methods solve this MDA problem by either developing complicated approximate algorithms, or simplifying MDA as a 2D assignment problem based upon the information extracted only from adjacent frames. In this paper, we show that the relation between associations of two observations is the equivalence relation in the data association problem, based on the spatial-temporal constraint that the trajectories of different objects must be disjoint. Therefore, the MDA problem can be equivalently divided into independent subproblems by equivalence partitioning. In contrast to existing works for solving the MDA problem, we develop a connected component model (CCM) by exploiting the constraints of the data association and the equivalence relation on the constraints. Based upon CCM, we can efficiently obtain the global solution of the MDA problem for multi-object tracking by optimizing a sequence of independent data association subproblems. Experiments on challenging public data sets demonstrate that our algorithm outperforms the state-of-the-art approaches.

  4. Novel approaches for road congestion mitigation.

    DOT National Transportation Integrated Search

    2012-07-02

    Transportation planning is usually aiming to solve two problems: the traffic assignment and the toll pricing problems. The latter one utilizes information from the first one, in order to find the optimal set of tolls that is the set of tolls that lea...

  5. Novel approaches for road congestion minimization.

    DOT National Transportation Integrated Search

    2012-07-01

    Transportation planning is usually aiming to solve two problems: the traffic assignment and the toll pricing problems. The latter one utilizes information from the first one, in order to find the optimal set of tolls that is the set of tolls that lea...

  6. C1 finite elements on non-tensor-product 2d and 3d manifolds

    PubMed Central

    Nguyen, Thien; Karčiauskas, Kęstutis; Peters, Jörg

    2015-01-01

    Geometrically continuous (Gk) constructions naturally yield families of finite elements for isogeometric analysis (IGA) that are Ck also for non-tensor-product layout. This paper describes and analyzes one such concrete C1 geometrically generalized IGA element (short: gIGA element) that generalizes bi-quadratic splines to quad meshes with irregularities. The new gIGA element is based on a recently-developed G1 surface construction that recommends itself by its a B-spline-like control net, low (least) polynomial degree, good shape properties and reproduction of quadratics at irregular (extraordinary) points. Remarkably, for Poisson’s equation on the disk using interior vertices of valence 3 and symmetric layout, we observe O(h3) convergence in the L∞ norm for this family of elements. Numerical experiments confirm the elements to be effective for solving the trivariate Poisson equation on the solid cylinder, deformations thereof (a turbine blade), modeling and computing geodesics on smooth free-form surfaces via the heat equation, for solving the biharmonic equation on the disk and for Koiter-type thin-shell analysis. PMID:26594070

  7. C1 finite elements on non-tensor-product 2d and 3d manifolds.

    PubMed

    Nguyen, Thien; Karčiauskas, Kęstutis; Peters, Jörg

    2016-01-01

    Geometrically continuous ( G k ) constructions naturally yield families of finite elements for isogeometric analysis (IGA) that are C k also for non-tensor-product layout. This paper describes and analyzes one such concrete C 1 geometrically generalized IGA element (short: gIGA element) that generalizes bi-quadratic splines to quad meshes with irregularities. The new gIGA element is based on a recently-developed G 1 surface construction that recommends itself by its a B-spline-like control net, low (least) polynomial degree, good shape properties and reproduction of quadratics at irregular (extraordinary) points. Remarkably, for Poisson's equation on the disk using interior vertices of valence 3 and symmetric layout, we observe O ( h 3 ) convergence in the L ∞ norm for this family of elements. Numerical experiments confirm the elements to be effective for solving the trivariate Poisson equation on the solid cylinder, deformations thereof (a turbine blade), modeling and computing geodesics on smooth free-form surfaces via the heat equation, for solving the biharmonic equation on the disk and for Koiter-type thin-shell analysis.

  8. Manycast routing, modulation level and spectrum assignment over elastic optical networks

    NASA Astrophysics Data System (ADS)

    Luo, Xiao; Zhao, Yang; Chen, Xue; Wang, Lei; Zhang, Min; Zhang, Jie; Ji, Yuefeng; Wang, Huitao; Wang, Taili

    2017-07-01

    Manycast is a point to multi-point transmission framework that requires a subset of destination nodes successfully reached. It is particularly applicable for dealing with large amounts of data simultaneously in bandwidth-hungry, dynamic and cloud-based applications. As rapid increasing of traffics in these applications, the elastic optical networks (EONs) may be relied on to achieve high throughput manycast. In terms of finer spectrum granularity, the EONs could reach flexible accessing to network spectrum and efficient providing exact spectrum resource to demands. In this paper, we focus on the manycast routing, modulation level and spectrum assignment (MA-RMLSA) problem in EONs. Both EONs planning with static manycast traffic and EONs provisioning with dynamic manycast traffic are investigated. An integer linear programming (ILP) model is formulated to derive MA-RMLSA problem in static manycast scenario. Then corresponding heuristic algorithm called manycast routing, modulation level and spectrum assignment genetic algorithm (MA-RMLSA-GA) is proposed to adapt for both static and dynamic manycast scenarios. The MA-RMLSA-GA optimizes MA-RMLSA problem in destination nodes selection, routing light-tree constitution, modulation level allocation and spectrum resource assignment jointly, to achieve an effective improvement in network performance. Simulation results reveal that MA-RMLSA strategies offered by MA-RMLSA-GA have slightly disparity from the optimal solutions provided by ILP model in static scenario. Moreover, the results demonstrate that MA-RMLSA-GA realizes a highly efficient MA-RMLSA strategy with the lowest blocking probability in dynamic scenario compared with benchmark algorithms.

  9. Pre-Service Teacher Scientific Behavior: Comparative Study of Paired Science Project Assignments

    ERIC Educational Resources Information Center

    Bulunuz, Mizrap; Tapan Broutin, Menekse Seden; Bulunuz, Nermin

    2016-01-01

    Problem Statement: University students usually lack the skills to rigorously define a multi-dimensional real-life problem and its limitations in an explicit, clear and testable way, which prevents them from forming a reliable method, obtaining relevant results and making balanced judgments to solve a problem. Purpose of the Study: The study…

  10. A Randomized Trial of Brief Interventions for Problem and Pathological Gamblers

    ERIC Educational Resources Information Center

    Petry, Nancy M.; Weinstock, Jeremiah; Ledgerwood, David M.; Morasco, Benjamin

    2008-01-01

    Limited research exists regarding methods for reducing problem gambling. Problem gamblers (N = 180) were randomly assigned to assessment only control, 10 min of brief advice, 1 session of motivational enhancement therapy (MET), or 1 session of MET plus 3 sessions of cognitive-behavioral therapy. Gambling was assessed at baseline, at 6 weeks, and…

  11. Can Short Duration Visual Cues Influence Students' Reasoning and Eye Movements in Physics Problems?

    ERIC Educational Resources Information Center

    Madsen, Adrian; Rouinfar, Amy; Larson, Adam M.; Loschky, Lester C.; Rebello, N. Sanjay

    2013-01-01

    We investigate the effects of visual cueing on students' eye movements and reasoning on introductory physics problems with diagrams. Participants in our study were randomly assigned to either the cued or noncued conditions, which differed by whether the participants saw conceptual physics problems overlaid with dynamic visual cues. Students in the…

  12. Writing for Business: A Graduate-Level Course in Problem-Solving

    ERIC Educational Resources Information Center

    Seifert, Christine

    2009-01-01

    This paper details an assignment sequence that requires graduate students in an applied communication program to identify problems that clients may not be aware of. Good writing and good problem-solving are "inextricably linked to [a student's] ability to frame an issue, gather, and analyze information, and to structure a helpful response" (Musso,…

  13. Some insights on hard quadratic assignment problem instances

    NASA Astrophysics Data System (ADS)

    Hussin, Mohamed Saifullah

    2017-11-01

    Since the formal introduction of metaheuristics, a huge number Quadratic Assignment Problem (QAP) instances have been introduced. Those instances however are loosely-structured, and therefore made it difficult to perform any systematic analysis. The QAPLIB for example, is a library that contains a huge number of QAP benchmark instances that consists of instances with different size and structure, but with a very limited availability for every instance type. This prevents researchers from performing organized study on those instances, such as parameter tuning and testing. In this paper, we will discuss several hard instances that have been introduced over the years, and algorithms that have been used for solving them.

  14. Solving the Credit Assignment Problem With the Prefrontal Cortex

    PubMed Central

    Stolyarova, Alexandra

    2018-01-01

    In naturalistic multi-cue and multi-step learning tasks, where outcomes of behavior are delayed in time, discovering which choices are responsible for rewards can present a challenge, known as the credit assignment problem. In this review, I summarize recent work that highlighted a critical role for the prefrontal cortex (PFC) in assigning credit where it is due in tasks where only a few of the multitude of cues or choices are relevant to the final outcome of behavior. Collectively, these investigations have provided compelling support for specialized roles of the orbitofrontal (OFC), anterior cingulate (ACC), and dorsolateral prefrontal (dlPFC) cortices in contingent learning. However, recent work has similarly revealed shared contributions and emphasized rich and heterogeneous response properties of neurons in these brain regions. Such functional overlap is not surprising given the complexity of reciprocal projections spanning the PFC. In the concluding section, I overview the evidence suggesting that the OFC, ACC and dlPFC communicate extensively, sharing the information about presented options, executed decisions and received rewards, which enables them to assign credit for outcomes to choices on which they are contingent. This account suggests that lesion or inactivation/inhibition experiments targeting a localized PFC subregion will be insufficient to gain a fine-grained understanding of credit assignment during learning and instead poses refined questions for future research, shifting the focus from focal manipulations to experimental techniques targeting cortico-cortical projections. PMID:29636659

  15. Using Public Speaking and Critical Thinking To Increase Self-Esteem in the Multi-Cultural College Prep Composition Classroom.

    ERIC Educational Resources Information Center

    Weissberg, Michael W.

    In an effort to improve the writing performance of non-native English-speaking students in a college preparatory composition course, a project was undertaken to reduce problems of self-esteem caused by communication apprehension through a speech assignment involving critical thinking and peer reviews. To evaluate the effect of the assignment, the…

  16. Assignment Problem for the U.S. Marine Corps: Regional, Culture, and Language Familiarization Program

    DTIC Science & Technology

    2013-12-01

    patients. The top trading cycle is popular in market design because it can be Pareto efficient and strategy proof when making assignments such as...29 1. Results for Group 1: Platoons 1 and 2 .............................................29 2...Results for Group 2: Platoons 3 and 4 .............................................31 3. Results for Group 3: Platoons 5 and 6

  17. An Alternative Optimization Model and Robust Experimental Design for the Assignment Scheduling Capability for Unmanned Aerial Vehicles (ASC-U) Simulation

    DTIC Science & Technology

    2007-06-01

    introduces ASC-U’s approach for solving the dynamic UAV allocation problem. 26 Christopher J...18 Figure 6. Assignments Dynamics Example (after) .........................................................20 Figure 7. ASC-U Dynamic Cueing...decisions in order to respond to the dynamic environment they face. Thus, to succeed, the Army’s transformation cannot rely

  18. Model of load distribution for earth observation satellite

    NASA Astrophysics Data System (ADS)

    Tu, Shumin; Du, Min; Li, Wei

    2017-03-01

    For the system of multiple types of EOS (Earth Observing Satellites), it is a vital issue to assure that each type of payloads carried by the group of EOS can be used efficiently and reasonably for in astronautics fields. Currently, most of researches on configuration of satellite and payloads focus on the scheduling for launched satellites. However, the assignments of payloads for un-launched satellites are bit researched, which are the same crucial as the scheduling of tasks. Moreover, the current models of satellite resources scheduling lack of more general characteristics. Referring the idea about roles-based access control (RBAC) of information system, this paper brings forward a model based on role-mining of RBAC to improve the generality and foresight of the method of assignments of satellite-payload. By this way, the assignment of satellite-payload can be mapped onto the problem of role-mining. A novel method will be introduced, based on the idea of biclique-combination in graph theory and evolutionary algorithm in intelligence computing, to address the role-mining problem of satellite-payload assignments. The simulation experiments are performed to verify the novel method. Finally, the work of this paper is concluded.

  19. Psychological functioning in adolescents referred to specialist gender identity clinics across Europe: a clinical comparison study between four clinics.

    PubMed

    de Graaf, Nastasja M; Cohen-Kettenis, Peggy T; Carmichael, Polly; de Vries, Annelou L C; Dhondt, Karlien; Laridaen, Jolien; Pauli, Dagmar; Ball, Juliane; Steensma, Thomas D

    2018-07-01

    Adolescents seeking professional help with their gender identity development often present with psychological difficulties. Existing literature on psychological functioning of gender diverse young people is limited and mostly bound to national chart reviews. This study examined the prevalence of psychological functioning and peer relationship problems in adolescents across four European specialist gender services (The Netherlands, Belgium, the UK, and Switzerland), using the Child Behavioural Checklist (CBCL) and the Youth Self-Report (YSR). Differences in psychological functioning and peer relationships were found in gender diverse adolescents across Europe. Overall, emotional and behavioural problems and peer relationship problems were most prevalent in adolescents from the UK, followed by Switzerland and Belgium. The least behavioural and emotional problems and peer relationship problems were reported by adolescents from The Netherlands. Across the four clinics, a similar pattern of gender differences was found. Birth-assigned girls showed more behavioural problems and externalising problems in the clinical range, as reported by their parents. According to self-report, internalising problems in the clinical range were more prevalent in adolescent birth-assigned boys. More research is needed to gain a better understanding of the difference in clinical presentations in gender diverse adolescents and to investigate what contextual factors that may contribute to this.

  20. Multi-Objectivising Combinatorial Optimisation Problems by Means of Elementary Landscape Decompositions.

    PubMed

    Ceberio, Josu; Calvo, Borja; Mendiburu, Alexander; Lozano, Jose A

    2018-02-15

    In the last decade, many works in combinatorial optimisation have shown that, due to the advances in multi-objective optimisation, the algorithms from this field could be used for solving single-objective problems as well. In this sense, a number of papers have proposed multi-objectivising single-objective problems in order to use multi-objective algorithms in their optimisation. In this article, we follow up this idea by presenting a methodology for multi-objectivising combinatorial optimisation problems based on elementary landscape decompositions of their objective function. Under this framework, each of the elementary landscapes obtained from the decomposition is considered as an independent objective function to optimise. In order to illustrate this general methodology, we consider four problems from different domains: the quadratic assignment problem and the linear ordering problem (permutation domain), the 0-1 unconstrained quadratic optimisation problem (binary domain), and the frequency assignment problem (integer domain). We implemented two widely known multi-objective algorithms, NSGA-II and SPEA2, and compared their performance with that of a single-objective GA. The experiments conducted on a large benchmark of instances of the four problems show that the multi-objective algorithms clearly outperform the single-objective approaches. Furthermore, a discussion on the results suggests that the multi-objective space generated by this decomposition enhances the exploration ability, thus permitting NSGA-II and SPEA2 to obtain better results in the majority of the tested instances.

  1. A test of geographic assignment using isotope tracers in feathers of known origin

    USGS Publications Warehouse

    Wunder, Michael B.; Kester, C.L.; Knopf, F.L.; Rye, R.O.

    2005-01-01

    We used feathers of known origin collected from across the breeding range of a migratory shorebird to test the use of isotope tracers for assigning breeding origins. We analyzed δD, δ13C, and δ15N in feathers from 75 mountain plover (Charadrius montanus) chicks sampled in 2001 and from 119 chicks sampled in 2002. We estimated parameters for continuous-response inverse regression models and for discrete-response Bayesian probability models from data for each year independently. We evaluated model predictions with both the training data and by using the alternate year as an independent test dataset. Our results provide weak support for modeling latitude and isotope values as monotonic functions of one another, especially when data are pooled over known sources of variation such as sample year or location. We were unable to make even qualitative statements, such as north versus south, about the likely origin of birds using both δD and δ13C in inverse regression models; results were no better than random assignment. Probability models provided better results and a more natural framework for the problem. Correct assignment rates were highest when considering all three isotopes in the probability framework, but the use of even a single isotope was better than random assignment. The method appears relatively robust to temporal effects and is most sensitive to the isotope discrimination gradients over which samples are taken. We offer that the problem of using isotope tracers to infer geographic origin is best framed as one of assignment, rather than prediction.

  2. Engineering calculations for communications satellite systems planning

    NASA Technical Reports Server (NTRS)

    Reilly, C. H.; Levis, C. A.; Mount-Campbell, C.; Gonsalvez, D. J.; Wang, C. W.; Yamamura, Y.

    1985-01-01

    Computer-based techniques for optimizing communications-satellite orbit and frequency assignments are discussed. A gradient-search code was tested against a BSS scenario derived from the RARC-83 data. Improvement was obtained, but each iteration requires about 50 minutes of IBM-3081 CPU time. Gradient-search experiments on a small FSS test problem, consisting of a single service area served by 8 satellites, showed quickest convergence when the satellites were all initially placed near the center of the available orbital arc with moderate spacing. A transformation technique is proposed for investigating the surface topography of the objective function used in the gradient-search method. A new synthesis approach is based on transforming single-entry interference constraints into corresponding constraints on satellite spacings. These constraints are used with linear objective functions to formulate the co-channel orbital assignment task as a linear-programming (LP) problem or mixed integer programming (MIP) problem. Globally optimal solutions are always found with the MIP problems, but not necessarily with the LP problems. The MIP solutions can be used to evaluate the quality of the LP solutions. The initial results are very encouraging.

  3. About approximation of integer factorization problem by the combination fixed-point iteration method and Bayesian rounding for quantum cryptography

    NASA Astrophysics Data System (ADS)

    Ogorodnikov, Yuri; Khachay, Michael; Pljonkin, Anton

    2018-04-01

    We describe the possibility of employing the special case of the 3-SAT problem stemming from the well known integer factorization problem for the quantum cryptography. It is known, that for every instance of our 3-SAT setting the given 3-CNF is satisfiable by a unique truth assignment, and the goal is to find this assignment. Since the complexity status of the factorization problem is still undefined, development of approximation algorithms and heuristics adopts interest of numerous researchers. One of promising approaches to construction of approximation techniques is based on real-valued relaxation of the given 3-CNF followed by minimizing of the appropriate differentiable loss function, and subsequent rounding of the fractional minimizer obtained. Actually, algorithms developed this way differ by the rounding scheme applied on their final stage. We propose a new rounding scheme based on Bayesian learning. The article shows that the proposed method can be used to determine the security in quantum key distribution systems. In the quantum distribution the Shannon rules is applied and the factorization problem is paramount when decrypting secret keys.

  4. Decision support for hospital bed management using adaptable individual length of stay estimations and shared resources

    PubMed Central

    2013-01-01

    Background Elective patient admission and assignment planning is an important task of the strategic and operational management of a hospital and early on became a central topic of clinical operations research. The management of hospital beds is an important subtask. Various approaches have been proposed, involving the computation of efficient assignments with regard to the patients’ condition, the necessity of the treatment, and the patients’ preferences. However, these approaches are mostly based on static, unadaptable estimates of the length of stay and, thus, do not take into account the uncertainty of the patient’s recovery. Furthermore, the effect of aggregated bed capacities have not been investigated in this context. Computer supported bed management, combining an adaptable length of stay estimation with the treatment of shared resources (aggregated bed capacities) has not yet been sufficiently investigated. The aim of our work is: 1) to define a cost function for patient admission taking into account adaptable length of stay estimations and aggregated resources, 2) to define a mathematical program formally modeling the assignment problem and an architecture for decision support, 3) to investigate four algorithmic methodologies addressing the assignment problem and one base-line approach, and 4) to evaluate these methodologies w.r.t. cost outcome, performance, and dismissal ratio. Methods The expected free ward capacity is calculated based on individual length of stay estimates, introducing Bernoulli distributed random variables for the ward occupation states and approximating the probability densities. The assignment problem is represented as a binary integer program. Four strategies for solving the problem are applied and compared: an exact approach, using the mixed integer programming solver SCIP; and three heuristic strategies, namely the longest expected processing time, the shortest expected processing time, and random choice. A baseline approach serves to compare these optimization strategies with a simple model of the status quo. All the approaches are evaluated by a realistic discrete event simulation: the outcomes are the ratio of successful assignments and dismissals, the computation time, and the model’s cost factors. Results A discrete event simulation of 226,000 cases shows a reduction of the dismissal rate compared to the baseline by more than 30 percentage points (from a mean dismissal ratio of 74.7% to 40.06% comparing the status quo with the optimization strategies). Each of the optimization strategies leads to an improved assignment. The exact approach has only a marginal advantage over the heuristic strategies in the model’s cost factors (≤3%). Moreover,this marginal advantage was only achieved at the price of a computational time fifty times that of the heuristic models (an average computing time of 141 s using the exact method, vs. 2.6 s for the heuristic strategy). Conclusions In terms of its performance and the quality of its solution, the heuristic strategy RAND is the preferred method for bed assignment in the case of shared resources. Future research is needed to investigate whether an equally marked improvement can be achieved in a large scale clinical application study, ideally one comprising all the departments involved in admission and assignment planning. PMID:23289448

  5. Decision support for hospital bed management using adaptable individual length of stay estimations and shared resources.

    PubMed

    Schmidt, Robert; Geisler, Sandra; Spreckelsen, Cord

    2013-01-07

    Elective patient admission and assignment planning is an important task of the strategic and operational management of a hospital and early on became a central topic of clinical operations research. The management of hospital beds is an important subtask. Various approaches have been proposed, involving the computation of efficient assignments with regard to the patients' condition, the necessity of the treatment, and the patients' preferences. However, these approaches are mostly based on static, unadaptable estimates of the length of stay and, thus, do not take into account the uncertainty of the patient's recovery. Furthermore, the effect of aggregated bed capacities have not been investigated in this context. Computer supported bed management, combining an adaptable length of stay estimation with the treatment of shared resources (aggregated bed capacities) has not yet been sufficiently investigated. The aim of our work is: 1) to define a cost function for patient admission taking into account adaptable length of stay estimations and aggregated resources, 2) to define a mathematical program formally modeling the assignment problem and an architecture for decision support, 3) to investigate four algorithmic methodologies addressing the assignment problem and one base-line approach, and 4) to evaluate these methodologies w.r.t. cost outcome, performance, and dismissal ratio. The expected free ward capacity is calculated based on individual length of stay estimates, introducing Bernoulli distributed random variables for the ward occupation states and approximating the probability densities. The assignment problem is represented as a binary integer program. Four strategies for solving the problem are applied and compared: an exact approach, using the mixed integer programming solver SCIP; and three heuristic strategies, namely the longest expected processing time, the shortest expected processing time, and random choice. A baseline approach serves to compare these optimization strategies with a simple model of the status quo. All the approaches are evaluated by a realistic discrete event simulation: the outcomes are the ratio of successful assignments and dismissals, the computation time, and the model's cost factors. A discrete event simulation of 226,000 cases shows a reduction of the dismissal rate compared to the baseline by more than 30 percentage points (from a mean dismissal ratio of 74.7% to 40.06% comparing the status quo with the optimization strategies). Each of the optimization strategies leads to an improved assignment. The exact approach has only a marginal advantage over the heuristic strategies in the model's cost factors (≤3%). Moreover,this marginal advantage was only achieved at the price of a computational time fifty times that of the heuristic models (an average computing time of 141 s using the exact method, vs. 2.6 s for the heuristic strategy). In terms of its performance and the quality of its solution, the heuristic strategy RAND is the preferred method for bed assignment in the case of shared resources. Future research is needed to investigate whether an equally marked improvement can be achieved in a large scale clinical application study, ideally one comprising all the departments involved in admission and assignment planning.

  6. A Biogeography-Based Optimization Algorithm Hybridized with Tabu Search for the Quadratic Assignment Problem

    PubMed Central

    Lim, Wee Loon; Wibowo, Antoni; Desa, Mohammad Ishak; Haron, Habibollah

    2016-01-01

    The quadratic assignment problem (QAP) is an NP-hard combinatorial optimization problem with a wide variety of applications. Biogeography-based optimization (BBO), a relatively new optimization technique based on the biogeography concept, uses the idea of migration strategy of species to derive algorithm for solving optimization problems. It has been shown that BBO provides performance on a par with other optimization methods. A classical BBO algorithm employs the mutation operator as its diversification strategy. However, this process will often ruin the quality of solutions in QAP. In this paper, we propose a hybrid technique to overcome the weakness of classical BBO algorithm to solve QAP, by replacing the mutation operator with a tabu search procedure. Our experiments using the benchmark instances from QAPLIB show that the proposed hybrid method is able to find good solutions for them within reasonable computational times. Out of 61 benchmark instances tested, the proposed method is able to obtain the best known solutions for 57 of them. PMID:26819585

  7. A Biogeography-Based Optimization Algorithm Hybridized with Tabu Search for the Quadratic Assignment Problem.

    PubMed

    Lim, Wee Loon; Wibowo, Antoni; Desa, Mohammad Ishak; Haron, Habibollah

    2016-01-01

    The quadratic assignment problem (QAP) is an NP-hard combinatorial optimization problem with a wide variety of applications. Biogeography-based optimization (BBO), a relatively new optimization technique based on the biogeography concept, uses the idea of migration strategy of species to derive algorithm for solving optimization problems. It has been shown that BBO provides performance on a par with other optimization methods. A classical BBO algorithm employs the mutation operator as its diversification strategy. However, this process will often ruin the quality of solutions in QAP. In this paper, we propose a hybrid technique to overcome the weakness of classical BBO algorithm to solve QAP, by replacing the mutation operator with a tabu search procedure. Our experiments using the benchmark instances from QAPLIB show that the proposed hybrid method is able to find good solutions for them within reasonable computational times. Out of 61 benchmark instances tested, the proposed method is able to obtain the best known solutions for 57 of them.

  8. The Transitory Phase to the Attainment of Self-Regulatory Skill in Mathematical Problem Solving

    ERIC Educational Resources Information Center

    Lazakidou, G.; Paraskeva, F.; Retalis, S.

    2007-01-01

    Three phases of development of self-regulatory skill in the domain of mathematical problem solving were designed to examine students' behaviour and the effects on their problem solving ability. Forty-eight Grade 4 students (10 year olds) participated in this pilot study. The students were randomly assigned to one of three groups, each representing…

  9. Effect of Computer-Presented Organizational/Memory Aids on Problem Solving Behavior.

    ERIC Educational Resources Information Center

    Steinberg, Esther R.; And Others

    This research studied the effects of computer-presented organizational/memory aids on problem solving behavior. The aids were either matrix or verbal charts shown on the display screen next to the problem. The 104 college student subjects were randomly assigned to one of the four conditions: type of chart (matrix or verbal chart) and use of charts…

  10. The Roles of Women in the Army and Their Impact on Military Operations and Organizations.

    ERIC Educational Resources Information Center

    Batts, John H.; And Others

    Problems inherent in the expanded utilization of female soldiers in the U.S. Army are numerous. Attitudes of a wide sample of Army personnel, men and women, enlisted and officer, were surveyed pertaining to those problems. Some problems such as uniforms, billeting, assignments, and training are obvious and with proper planning can and will be…

  11. Effects of Cognitive Strategy Interventions and Cognitive Moderators on Word Problem Solving in Children at Risk for Problem Solving Difficulties

    ERIC Educational Resources Information Center

    Swanson, H. Lee; Lussier, Cathy; Orosco, Michael

    2013-01-01

    This study investigated the role of strategy instruction and cognitive abilities on word problem solving accuracy in children with math difficulties (MD). Elementary school children (N = 120) with and without MD were randomly assigned to 1 of 4 conditions: general-heuristic (e.g., underline question sentence), visual-schematic presentation…

  12. Using Educational Data Mining Methods to Assess Field-Dependent and Field-Independent Learners' Complex Problem Solving

    ERIC Educational Resources Information Center

    Angeli, Charoula; Valanides, Nicos

    2013-01-01

    The present study investigated the problem-solving performance of 101 university students and their interactions with a computer modeling tool in order to solve a complex problem. Based on their performance on the hidden figures test, students were assigned to three groups of field-dependent (FD), field-mixed (FM), and field-independent (FI)…

  13. Work, Productivity, and Human Performance: Practical Case Studies in Ergonomics, Human Factors and Human Engineering.

    ERIC Educational Resources Information Center

    Fraser, T. M.; Pityn, P. J.

    This book contains 12 case histories, each based on a real-life problem, that show how a manager can use common sense, knowledge, and interpersonal skills to solve problems in human performance at work. Each case study describes a worker's problem and provides background information and an assignment; solutions are suggested. The following cases…

  14. A two-stage approach to the depot shunting driver assignment problem with workload balance considerations.

    PubMed

    Wang, Jiaxi; Gronalt, Manfred; Sun, Yan

    2017-01-01

    Due to its environmentally sustainable and energy-saving characteristics, railway transportation nowadays plays a fundamental role in delivering passengers and goods. Emerged in the area of transportation planning, the crew (workforce) sizing problem and the crew scheduling problem have been attached great importance by the railway industry and the scientific community. In this paper, we aim to solve the two problems by proposing a novel two-stage optimization approach in the context of the electric multiple units (EMU) depot shunting driver assignment problem. Given a predefined depot shunting schedule, the first stage of the approach focuses on determining an optimal size of shunting drivers. While the second stage is formulated as a bi-objective optimization model, in which we comprehensively consider the objectives of minimizing the total walking distance and maximizing the workload balance. Then we combine the normalized normal constraint method with a modified Pareto filter algorithm to obtain Pareto solutions for the bi-objective optimization problem. Furthermore, we conduct a series of numerical experiments to demonstrate the proposed approach. Based on the computational results, the regression analysis yield a driver size predictor and the sensitivity analysis give some interesting insights that are useful for decision makers.

  15. A two-stage approach to the depot shunting driver assignment problem with workload balance considerations

    PubMed Central

    Gronalt, Manfred; Sun, Yan

    2017-01-01

    Due to its environmentally sustainable and energy-saving characteristics, railway transportation nowadays plays a fundamental role in delivering passengers and goods. Emerged in the area of transportation planning, the crew (workforce) sizing problem and the crew scheduling problem have been attached great importance by the railway industry and the scientific community. In this paper, we aim to solve the two problems by proposing a novel two-stage optimization approach in the context of the electric multiple units (EMU) depot shunting driver assignment problem. Given a predefined depot shunting schedule, the first stage of the approach focuses on determining an optimal size of shunting drivers. While the second stage is formulated as a bi-objective optimization model, in which we comprehensively consider the objectives of minimizing the total walking distance and maximizing the workload balance. Then we combine the normalized normal constraint method with a modified Pareto filter algorithm to obtain Pareto solutions for the bi-objective optimization problem. Furthermore, we conduct a series of numerical experiments to demonstrate the proposed approach. Based on the computational results, the regression analysis yield a driver size predictor and the sensitivity analysis give some interesting insights that are useful for decision makers. PMID:28704489

  16. Design of multivariable feedback control systems via spectral assignment using reduced-order models and reduced-order observers

    NASA Technical Reports Server (NTRS)

    Mielke, R. R.; Tung, L. J.; Carraway, P. I., III

    1984-01-01

    The feasibility of using reduced order models and reduced order observers with eigenvalue/eigenvector assignment procedures is investigated. A review of spectral assignment synthesis procedures is presented. Then, a reduced order model which retains essential system characteristics is formulated. A constant state feedback matrix which assigns desired closed loop eigenvalues and approximates specified closed loop eigenvectors is calculated for the reduced order model. It is shown that the eigenvalue and eigenvector assignments made in the reduced order system are retained when the feedback matrix is implemented about the full order system. In addition, those modes and associated eigenvectors which are not included in the reduced order model remain unchanged in the closed loop full order system. The full state feedback design is then implemented by using a reduced order observer. It is shown that the eigenvalue and eigenvector assignments of the closed loop full order system rmain unchanged when a reduced order observer is used. The design procedure is illustrated by an actual design problem.

  17. Design of multivariable feedback control systems via spectral assignment using reduced-order models and reduced-order observers

    NASA Technical Reports Server (NTRS)

    Mielke, R. R.; Tung, L. J.; Carraway, P. I., III

    1985-01-01

    The feasibility of using reduced order models and reduced order observers with eigenvalue/eigenvector assignment procedures is investigated. A review of spectral assignment synthesis procedures is presented. Then, a reduced order model which retains essential system characteristics is formulated. A constant state feedback matrix which assigns desired closed loop eigenvalues and approximates specified closed loop eigenvectors is calculated for the reduced order model. It is shown that the eigenvalue and eigenvector assignments made in the reduced order system are retained when the feedback matrix is implemented about the full order system. In addition, those modes and associated eigenvectors which are not included in the reduced order model remain unchanged in the closed loop full order system. The fulll state feedback design is then implemented by using a reduced order observer. It is shown that the eigenvalue and eigenvector assignments of the closed loop full order system remain unchanged when a reduced order observer is used. The design procedure is illustrated by an actual design problem.

  18. The evolving market structures of gambling: case studies modelling the socioeconomic assignment of gaming machines in Melbourne and Sydney, Australia.

    PubMed

    Marshall, David C; Baker, Robert G V

    2002-01-01

    The expansion of gambling industries worldwide is intertwined with the growing government dependence on gambling revenue for fiscal assignments. In Australia, electronic gaming machines (EGMs) have dominated recent gambling industry growth. As EGMs have proliferated, growing recognition has emerged that EGM distribution closely reflects levels of socioeconomic disadvantage. More machines are located in less advantaged regions. This paper analyses time-series socioeconomic distributions of EGMs in Melbourne, Australia, an immature EGM market, and then compares the findings with the mature market in Sydney. Similar findings in both cities suggest that market assignment of EGMs transcends differences in historical and legislative environments. This indicates that similar underlying structures are evident in both markets. Modelling the spatial structures of gambling markets provides an opportunity to identify regions most at risk of gambling related problems. Subsequently, policies can be formulated which ensure fiscal revenue from gambling can be better targeted towards regions likely to be most afflicted by excessive gambling-related problems.

  19. On the stabilizability of multivariable systems by minimum order compensation

    NASA Technical Reports Server (NTRS)

    Byrnes, C. I.; Anderson, B. D. O.

    1983-01-01

    In this paper, a derivation is provided of the necessary condition, mp equal to or greater than n, for stabilizability by constant gain feedback of the generic degree n, p x m system. This follows from another of the main results, which asserts that generic stabilizability is equivalent to generic solvability of a deadbeat control problem, provided mp equal to or less than n. Taken together, these conclusions make it possible to make some sharp statements concerning minimum order stabilization. The techniques are primarily drawn from decision algebra and classical algebraic geometry and have additional consequences for problems of stabilizability and pole-assignability. Among these are the decidability (by a Sturm test) of the equivalence of generic pole-assignability and generic stabilizability, the semi-algebraic nature of the minimum order, q, of a stabilizing compensator, and the nonexistence of formulae involving rational operations and extraction of square roots for pole-assigning gains when they exist, answering in the negative a question raised by Anderson, Bose, and Jury (1975).

  20. Design of a Software Configuration for Real-Time Multimedia Group Communication; HNUMTP

    NASA Astrophysics Data System (ADS)

    Park, Gil-Cheol

    This paper designs transport protocol of multi-session/channel method for real time multimedia group telecommunication and realizes it. The special features of the designed and realized protocol are first, that it solved the sync problem which is the specific character of multimedia telecommunication by using multi-channel method protocol. Usual multimedia telecommunication is assigned one channel by each media data. This paper shortened the phenomenon that waits data for sync of receiving part by assigning more than one channel for the channel that has a lot of data per hour as video data. The problem of intermedia synchronization that happens then could be solved by sending temporal/spacial related data among data assigning extra control channel. Second, that it does integrated management for sessions. Each session is one group telecommunication unit which supports mutual working environment that is independent. Each session communicates the participants in the group independently, the session manager manages all the communication among groups and lets media sources connected with all network be operated efficiently.

  1. Support of NASA quality requirements by defense contract administration services regions

    NASA Technical Reports Server (NTRS)

    Farrar, Hiram D.

    1966-01-01

    Defense Contract Administration Services Regions (DCASR) quality assurance personnel performing under NASA Letters of Delegation must work closely with the assigned technical representative of the NASA centers. It is realized that technical personnel from the NASA Centers cannot make on-site visits as frequently as they would like to. However, DCASR quality assurance personnel would know the assigned NASA technical representative and should contact him when problems arise. The technical representative is the expert on the hardware and should be consulted on any problem area. It is important that the DCASR quality assurance personnel recommend to the delegating NASA Center any new or improved methods of which they may be aware which would assist in achieving the desired quality and reliability in NASA hardware. NASA expects assignment of competent personnel in the Quality Assurance functional area and is not only buying the individual's technical skill, but also his experience. Suggestions by field personnel can many times up-grade the quality or the hardware.

  2. Analysis of an Air Conditioning Coolant Solution for Metal Contamination Using Atomic Absorption Spectroscopy: An Undergraduate Instrumental Analysis Exercise Simulating an Industrial Assignment

    ERIC Educational Resources Information Center

    Baird, Michael J.

    2004-01-01

    A real-life analytical assignment is presented to students, who had to examine an air conditioning coolant solution for metal contamination using an atomic absorption spectroscopy (AAS). This hands-on access to a real problem exposed the undergraduate students to the mechanism of AAS, and promoted participation in a simulated industrial activity.

  3. Assignment Scheduling Capability for Unmanned Aerial Vehicles - A Discrete Event Simulation with Optimization in the Loop Approach to Solving a Scheduling Problem

    DTIC Science & Technology

    2006-12-01

    APPROACH As mentioned previously, ASCU does not use simulation in the traditional manner. Instead, it uses simulation to transition and capture the state...0 otherwise (by a heuristic discussed below). • Let cja = The reward for a UAV with sensor pack- age j being assigned to mission area a from the

  4. Using Problem-Based Learning with Large Groups.

    ERIC Educational Resources Information Center

    Buzzelli, Andrew R.

    1994-01-01

    At the Pennsylvania College of Optometry, a core course in pediatric optometry was revised to use a problem-centered approach and implemented with a class of 147 students. Students were assigned specific roles to distribute work evenly. A survey found students responded positively to this approach. (MSE)

  5. Method for protein structure alignment

    DOEpatents

    Blankenbecler, Richard; Ohlsson, Mattias; Peterson, Carsten; Ringner, Markus

    2005-02-22

    This invention provides a method for protein structure alignment. More particularly, the present invention provides a method for identification, classification and prediction of protein structures. The present invention involves two key ingredients. First, an energy or cost function formulation of the problem simultaneously in terms of binary (Potts) assignment variables and real-valued atomic coordinates. Second, a minimization of the energy or cost function by an iterative method, where in each iteration (1) a mean field method is employed for the assignment variables and (2) exact rotation and/or translation of atomic coordinates is performed, weighted with the corresponding assignment variables.

  6. Distributed Method to Optimal Profile Descent

    NASA Astrophysics Data System (ADS)

    Kim, Geun I.

    Current ground automation tools for Optimal Profile Descent (OPD) procedures utilize path stretching and speed profile change to maintain proper merging and spacing requirements at high traffic terminal area. However, low predictability of aircraft's vertical profile and path deviation during decent add uncertainty to computing estimated time of arrival, a key information that enables the ground control center to manage airspace traffic effectively. This paper uses an OPD procedure that is based on a constant flight path angle to increase the predictability of the vertical profile and defines an OPD optimization problem that uses both path stretching and speed profile change while largely maintaining the original OPD procedure. This problem minimizes the cumulative cost of performing OPD procedures for a group of aircraft by assigning a time cost function to each aircraft and a separation cost function to a pair of aircraft. The OPD optimization problem is then solved in a decentralized manner using dual decomposition techniques under inter-aircraft ADS-B mechanism. This method divides the optimization problem into more manageable sub-problems which are then distributed to the group of aircraft. Each aircraft solves its assigned sub-problem and communicate the solutions to other aircraft in an iterative process until an optimal solution is achieved thus decentralizing the computation of the optimization problem.

  7. Convex central configurations for the n-body problem

    NASA Astrophysics Data System (ADS)

    Xia, Zhihong

    We give a simple proof of a classical result of MacMillan and Bartky (Trans. Amer. Math. Soc. 34 (1932) 838) which states that, for any four positive masses and any assigned order, there is a convex planar central configuration. Moreover, we show that the central configurations we find correspond to local minima of the potential function with fixed moment of inertia. This allows us to show that there are at least six local minimum central configurations for the planar four-body problem. We also show that for any assigned order of five masses, there is at least one convex spatial central configuration of local minimum type. Our method also applies to some other cases.

  8. Planning Nurses in Maternity Care: a Stochastic Assignment Problem

    NASA Astrophysics Data System (ADS)

    Phillipson, Frank

    2015-05-01

    With 23 percent of all births taking place at home, The Netherlands have the highest rate of home births in the world. Also if the birth did not take place at home, it is not unusual for the mother and child to be out of hospital in a few hours after the baby was born. The explanation for both is the very well organised maternity care system. However, getting the right maternity care nurse available on time introduces a complex planning issue that can be recognized as a Stochastic Assignment Problem. In this paper an expert rule based approach is combined with scenario analysis to support the planner of the maternity care agency in his work.

  9. PLA realizations for VLSI state machines

    NASA Technical Reports Server (NTRS)

    Gopalakrishnan, S.; Whitaker, S.; Maki, G.; Liu, K.

    1990-01-01

    A major problem associated with state assignment procedures for VLSI controllers is obtaining an assignment that produces minimal or near minimal logic. The key item in Programmable Logic Array (PLA) area minimization is the number of unique product terms required by the design equations. This paper presents a state assignment algorithm for minimizing the number of product terms required to implement a finite state machine using a PLA. Partition algebra with predecessor state information is used to derive a near optimal state assignment. A maximum bound on the number of product terms required can be obtained by inspecting the predecessor state information. The state assignment algorithm presented is much simpler than existing procedures and leads to the same number of product terms or less. An area-efficient PLA structure implemented in a 1.0 micron CMOS process is presented along with a summary of the performance for a controller implemented using this design procedure.

  10. Global Optimization of Emergency Evacuation Assignments

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

    Han, Lee; Yuan, Fang; Chin, Shih-Miao

    2006-01-01

    Conventional emergency evacuation plans often assign evacuees to fixed routes or destinations based mainly on geographic proximity. Such approaches can be inefficient if the roads are congested, blocked, or otherwise dangerous because of the emergency. By not constraining evacuees to prespecified destinations, a one-destination evacuation approach provides flexibility in the optimization process. We present a framework for the simultaneous optimization of evacuation-traffic distribution and assignment. Based on the one-destination evacuation concept, we can obtain the optimal destination and route assignment by solving a one-destination traffic-assignment problem on a modified network representation. In a county-wide, large-scale evacuation case study, the one-destinationmore » model yields substantial improvement over the conventional approach, with the overall evacuation time reduced by more than 60 percent. More importantly, emergency planners can easily implement this framework by instructing evacuees to go to destinations that the one-destination optimization process selects.« less

  11. Fair Package Assignment

    NASA Astrophysics Data System (ADS)

    Lahaie, Sébastien; Parkes, David C.

    We consider the problem of fair allocation in the package assignment model, where a set of indivisible items, held by single seller, must be efficiently allocated to agents with quasi-linear utilities. A fair assignment is one that is efficient and envy-free. We consider a model where bidders have superadditive valuations, meaning that items are pure complements. Our central result is that core outcomes are fair and even coalition-fair over this domain, while fair distributions may not even exist for general valuations. Of relevance to auction design, we also establish that the core is equivalent to the set of anonymous-price competitive equilibria, and that superadditive valuations are a maximal domain that guarantees the existence of anonymous-price competitive equilibrium. Our results are analogs of core equivalence results for linear prices in the standard assignment model, and for nonlinear, non-anonymous prices in the package assignment model with general valuations.

  12. Symbolically Modeling Concurrent MCAPI Executions

    NASA Technical Reports Server (NTRS)

    Fischer, Topher; Mercer, Eric; Rungta, Neha

    2011-01-01

    Improper use of Inter-Process Communication (IPC) within concurrent systems often creates data races which can lead to bugs that are challenging to discover. Techniques that use Satisfiability Modulo Theories (SMT) problems to symbolically model possible executions of concurrent software have recently been proposed for use in the formal verification of software. In this work we describe a new technique for modeling executions of concurrent software that use a message passing API called MCAPI. Our technique uses an execution trace to create an SMT problem that symbolically models all possible concurrent executions and follows the same sequence of conditional branch outcomes as the provided execution trace. We check if there exists a satisfying assignment to the SMT problem with respect to specific safety properties. If such an assignment exists, it provides the conditions that lead to the violation of the property. We show how our method models behaviors of MCAPI applications that are ignored in previously published techniques.

  13. A Fuzzy Goal Programming for a Multi-Depot Distribution Problem

    NASA Astrophysics Data System (ADS)

    Nunkaew, Wuttinan; Phruksaphanrat, Busaba

    2010-10-01

    A fuzzy goal programming model for solving a Multi-Depot Distribution Problem (MDDP) is proposed in this research. This effective proposed model is applied for solving in the first step of Assignment First-Routing Second (AFRS) approach. Practically, a basic transportation model is firstly chosen to solve this kind of problem in the assignment step. After that the Vehicle Routing Problem (VRP) model is used to compute the delivery cost in the routing step. However, in the basic transportation model, only depot to customer relationship is concerned. In addition, the consideration of customer to customer relationship should also be considered since this relationship exists in the routing step. Both considerations of relationships are solved using Preemptive Fuzzy Goal Programming (P-FGP). The first fuzzy goal is set by a total transportation cost and the second fuzzy goal is set by a satisfactory level of the overall independence value. A case study is used for describing the effectiveness of the proposed model. Results from the proposed model are compared with the basic transportation model that has previously been used in this company. The proposed model can reduce the actual delivery cost in the routing step owing to the better result in the assignment step. Defining fuzzy goals by membership functions are more realistic than crisps. Furthermore, flexibility to adjust goals and an acceptable satisfactory level for decision maker can also be increased and the optimal solution can be obtained.

  14. Nurturing Students' Problem-Solving Skills and Engagement in Computer-Mediated Communications (CMC)

    ERIC Educational Resources Information Center

    Chen, Ching-Huei

    2014-01-01

    The present study sought to investigate how to enhance students' well- and ill-structured problem-solving skills and increase productive engagement in computer-mediated communication with the assistance of external prompts, namely procedural and reflection. Thirty-three graduate students were randomly assigned to two conditions: procedural and…

  15. Flight Director works out problem during STS-61 simulations

    NASA Image and Video Library

    1993-09-01

    Flight Director Robert E. Castle Jr. works out a problem during joint integrated simulations for the STS-61 mission. Astronauts assigned to extravehicular activity (EVA) tasks with the Hubble Space Telescope (HST) were simultaneously rehearsing in a neutral buoyancy tank at the Marshall Space Flight Center (MSFC) in Alabama.

  16. Problems and Solutions in Evaluating Child Outcomes of Large-Scale Educational Programs.

    ERIC Educational Resources Information Center

    Abrams, Allan S.; And Others

    1979-01-01

    Evaluation of large-scale programs is problematical because of inherent bias in assignment of treatment and control groups, resulting in serious regression artifacts even with the use of analysis of covariance designs. Nonuniformity of program implementation across sites and classrooms is also a problem. (Author/GSK)

  17. Effects of a Multifocused Prevention Program on Preschool Children's Competencies and Behavior Problems

    ERIC Educational Resources Information Center

    Stefan, Catrinel A.; Miclea, Mircea

    2013-01-01

    This study was designed to assess the effectiveness of a multifocused (child-, teacher- and parent-focused) prevention program for Romanian preschoolers, targeting social--emotional competence development, as well as reduction of behavior problems. Fourteen classrooms were randomly assigned to the intervention and control conditions. Subsequent…

  18. Can Group Discussions and Individualized Assignments Help More Students Succeed in Developmental Mathematics?

    ERIC Educational Resources Information Center

    Jaafar, Reem

    2015-01-01

    Students taking developmental mathematics courses resist attempting word problems when they are presented to them. Although word problems can help students contextualize learning, develop better understanding of the concepts and apply world knowledge, they constitute an impediment to students' progress in developmental mathematics courses. A…

  19. Mesh and Time-Step Independent Computational Fluid Dynamics (CFD) Solutions

    ERIC Educational Resources Information Center

    Nijdam, Justin J.

    2013-01-01

    A homework assignment is outlined in which students learn Computational Fluid Dynamics (CFD) concepts of discretization, numerical stability and accuracy, and verification in a hands-on manner by solving physically realistic problems of practical interest to engineers. The students solve a transient-diffusion problem numerically using the common…

  20. Education's Role in National Development Plans: Ten Country Cases.

    ERIC Educational Resources Information Center

    Thomas, R. Murray, Ed.

    The place education has been assigned in the national development programs of 10 nations is discussed, the problems that these countries have encountered in managing education are examined, and the measures adopted to solve educational problems are assessed. Included are the following papers: (1) "The Nature of National Development…

  1. Writing Children's Books in Sociology Class: An Innovative Approach to Teaching Social Problems to Undergraduate Students

    ERIC Educational Resources Information Center

    Maples, James N.; Taylor, William V.

    2013-01-01

    In this instructional article, we describe a non-traditional course assignment in which we ask students in our social problems courses to write, illustrate, and present a children's book about a social problem as part of the process of learning. Over the course of the semester, students utilize guided handouts to create a children's book exploring…

  2. The Big6: Not Just for Kids! Introduction to the Big6: Information Problem-Solving for Upper High School, College-Age, and Adult Students.

    ERIC Educational Resources Information Center

    Eisenberg, Mike; Spitzer, Kathy

    1998-01-01

    Explains the Big6 approach to information problem-solving based on exercises that were developed for college or upper high school students that can be completed during class sessions. Two of the exercises relate to personal information problems, and one relates Big6 skill areas to course assignments. (LRW)

  3. Nonlinear Multidimensional Assignment Problems Efficient Conic Optimization Methods and Applications

    DTIC Science & Technology

    2015-06-24

    WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Arizona State University School of Mathematical & Statistical Sciences 901 S...SUPPLEMENTARY NOTES 14. ABSTRACT The major goals of this project were completed: the exact solution of previously unsolved challenging combinatorial optimization... combinatorial optimization problem, the Directional Sensor Problem, was solved in two ways. First, heuristically in an engineering fashion and second, exactly

  4. All Seem to Need Immediate Attention--What Should I Do First? A Successful Principal in a New School Assignment at Secundaria Revolucion

    ERIC Educational Resources Information Center

    Torres-Arcadia, Celina; Flores-Kastanis, Eduardo

    2012-01-01

    This case provides emerging school administrators the opportunity to learn about the school system in Mexico. The case relates to a successful principal in her new school assignment. Martha Miramontes is an experienced and successful principal who quickly identified a number of challenges in her new campus. Even though each problem can be solved…

  5. Longitudinal Evaluation of the Importance of Homework Assignment Completion for the Academic Performance of Middle School Students with ADHD

    PubMed Central

    Langberg, Joshua M.; Dvorsky, Melissa R.; Molitor, Stephen J.; Bourchtein, Elizaveta; Eddy, Laura D.; Smith, Zoe; Schultz, Brandon K.; Evans, Steven W.

    2016-01-01

    The primary goal of this study was to longitudinally evaluate the homework assignment completion patterns of middle school age adolescents with ADHD, their associations with academic performance, and malleable predictors of homework assignment completion. Analyses were conducted on a sample of 104 middle school students comprehensively diagnosed with ADHD and followed for 18 months. Multiple teachers for each student provided information about the percentage of homework assignments turned in at five separate timepoints and school grades were collected quarterly. Results showed that agreement between teachers with respect to students’ assignment completion was high, with an intraclass correlation of .879 at baseline. Students with ADHD were turning in an average of 12% fewer assignments each academic quarter in comparison to teacher-reported classroom averages. Regression analyses revealed a robust association between the percentage of assignments turned in at baseline and school grades 18 months later, even after controlling for baseline grades, achievement (reading and math), intelligence, family income, and race. Cross-lag analyses demonstrated that the association between assignment completion and grades was reciprocal, with assignment completion negatively impacting grades and low grades in turn being associated with decreased future homework completion. Parent ratings of homework materials management abilities at baseline significantly predicted the percentage of assignments turned in as reported by teachers 18 months later. These findings demonstrate that homework assignment completion problems are persistent across time and an important intervention target for adolescents with ADHD. PMID:26931065

  6. Effects of Small-Group Tutoring with and without Validated Classroom Instruction on At-Risk Students' Math Problem Solving: Are Two Tiers of Prevention Better Than One?

    PubMed

    Fuchs, Lynn S; Fuchs, Douglas; Craddock, Caitlin; Hollenbeck, Kurstin N; Hamlett, Carol L; Schatschneider, Christopher

    2008-01-01

    The purpose of this study was to assess the effects of small-group tutoring with and without validated classroom instruction on at-risk (AR) students' math problem solving. Stratifying within schools, 119 3(rd)-grade classes were randomly assigned to conventional or validated problem-solving instruction (Hot Math [schema-broadening instruction]). Students identified as AR (n = 243) were randomly assigned, within classroom conditions, to receive Hot Math tutoring or not. Students were tested on problem-solving and math applications measures before and after 16 weeks of intervention. Analyses of variance, which accounted for the nested structure of the data, revealed the tutored students who received validated classroom instruction achieved better than tutored students who received conventional classroom instruction (ES = 1.34). However, the advantage for tutoring over no tutoring was similar whether or not students received validated or conventional classroom instruction (ESs = 1.18 and 1.13). Tutoring, not validated classroom instruction reduced the prevalence of math difficulty. Implications for responsiveness-to-intervention prevention models and for enhancing math problem-solving instruction are discussed.

  7. Efficient Credit Assignment through Evaluation Function Decomposition

    NASA Technical Reports Server (NTRS)

    Agogino, Adrian; Turner, Kagan; Mikkulainen, Risto

    2005-01-01

    Evolutionary methods are powerful tools in discovering solutions for difficult continuous tasks. When such a solution is encoded over multiple genes, a genetic algorithm faces the difficult credit assignment problem of evaluating how a single gene in a chromosome contributes to the full solution. Typically a single evaluation function is used for the entire chromosome, implicitly giving each gene in the chromosome the same evaluation. This method is inefficient because a gene will get credit for the contribution of all the other genes as well. Accurately measuring the fitness of individual genes in such a large search space requires many trials. This paper instead proposes turning this single complex search problem into a multi-agent search problem, where each agent has the simpler task of discovering a suitable gene. Gene-specific evaluation functions can then be created that have better theoretical properties than a single evaluation function over all genes. This method is tested in the difficult double-pole balancing problem, showing that agents using gene-specific evaluation functions can create a successful control policy in 20 percent fewer trials than the best existing genetic algorithms. The method is extended to more distributed problems, achieving 95 percent performance gains over tradition methods in the multi-rover domain.

  8. Run-time scheduling and execution of loops on message passing machines

    NASA Technical Reports Server (NTRS)

    Crowley, Kay; Saltz, Joel; Mirchandaney, Ravi; Berryman, Harry

    1989-01-01

    Sparse system solvers and general purpose codes for solving partial differential equations are examples of the many types of problems whose irregularity can result in poor performance on distributed memory machines. Often, the data structures used in these problems are very flexible. Crucial details concerning loop dependences are encoded in these structures rather than being explicitly represented in the program. Good methods for parallelizing and partitioning these types of problems require assignment of computations in rather arbitrary ways. Naive implementations of programs on distributed memory machines requiring general loop partitions can be extremely inefficient. Instead, the scheduling mechanism needs to capture the data reference patterns of the loops in order to partition the problem. First, the indices assigned to each processor must be locally numbered. Next, it is necessary to precompute what information is needed by each processor at various points in the computation. The precomputed information is then used to generate an execution template designed to carry out the computation, communication, and partitioning of data, in an optimized manner. The design is presented for a general preprocessor and schedule executer, the structures of which do not vary, even though the details of the computation and of the type of information are problem dependent.

  9. Run-time scheduling and execution of loops on message passing machines

    NASA Technical Reports Server (NTRS)

    Saltz, Joel; Crowley, Kathleen; Mirchandaney, Ravi; Berryman, Harry

    1990-01-01

    Sparse system solvers and general purpose codes for solving partial differential equations are examples of the many types of problems whose irregularity can result in poor performance on distributed memory machines. Often, the data structures used in these problems are very flexible. Crucial details concerning loop dependences are encoded in these structures rather than being explicitly represented in the program. Good methods for parallelizing and partitioning these types of problems require assignment of computations in rather arbitrary ways. Naive implementations of programs on distributed memory machines requiring general loop partitions can be extremely inefficient. Instead, the scheduling mechanism needs to capture the data reference patterns of the loops in order to partition the problem. First, the indices assigned to each processor must be locally numbered. Next, it is necessary to precompute what information is needed by each processor at various points in the computation. The precomputed information is then used to generate an execution template designed to carry out the computation, communication, and partitioning of data, in an optimized manner. The design is presented for a general preprocessor and schedule executer, the structures of which do not vary, even though the details of the computation and of the type of information are problem dependent.

  10. On designing for quality

    NASA Technical Reports Server (NTRS)

    Vajingortin, L. D.; Roisman, W. P.

    1991-01-01

    The problem of ensuring the required quality of products and/or technological processes often becomes more difficult due to the fact that there is not general theory of determining the optimal sets of value of the primary factors, i.e., of the output parameters of the parts and units comprising an object and ensuring the correspondence of the object's parameters to the quality requirements. This is the main reason for the amount of time taken to finish complex vital article. To create this theory, one has to overcome a number of difficulties and to solve the following tasks: the creation of reliable and stable mathematical models showing the influence of the primary factors on the output parameters; finding a new technique of assigning tolerances for primary factors with regard to economical, technological, and other criteria, the technique being based on the solution of the main problem; well reasoned assignment of nominal values for primary factors which serve as the basis for creating tolerances. Each of the above listed tasks is of independent importance. An attempt is made to give solutions for this problem. The above problem dealing with quality ensuring an mathematically formalized aspect is called the multiple inverse problem.

  11. Effects of Small-Group Tutoring with and without Validated Classroom Instruction on At-Risk Students' Math Problem Solving: Are Two Tiers of Prevention Better Than One?

    PubMed Central

    Fuchs, Lynn S.; Fuchs, Douglas; Craddock, Caitlin; Hollenbeck, Kurstin N.; Hamlett, Carol L.; Schatschneider, Christopher

    2008-01-01

    The purpose of this study was to assess the effects of small-group tutoring with and without validated classroom instruction on at-risk (AR) students' math problem solving. Stratifying within schools, 119 3rd-grade classes were randomly assigned to conventional or validated problem-solving instruction (Hot Math [schema-broadening instruction]). Students identified as AR (n = 243) were randomly assigned, within classroom conditions, to receive Hot Math tutoring or not. Students were tested on problem-solving and math applications measures before and after 16 weeks of intervention. Analyses of variance, which accounted for the nested structure of the data, revealed the tutored students who received validated classroom instruction achieved better than tutored students who received conventional classroom instruction (ES = 1.34). However, the advantage for tutoring over no tutoring was similar whether or not students received validated or conventional classroom instruction (ESs = 1.18 and 1.13). Tutoring, not validated classroom instruction reduced the prevalence of math difficulty. Implications for responsiveness-to-intervention prevention models and for enhancing math problem-solving instruction are discussed. PMID:19122881

  12. A Genetic Algorithm Approach for the TV Self-Promotion Assignment Problem

    NASA Astrophysics Data System (ADS)

    Pereira, Paulo A.; Fontes, Fernando A. C. C.; Fontes, Dalila B. M. M.

    2009-09-01

    We report on the development of a Genetic Algorithm (GA), which has been integrated into a Decision Support System to plan the best assignment of the weekly self-promotion space for a TV station. The problem addressed consists on deciding which shows to advertise and when such that the number of viewers, of an intended group or target, is maximized. The GA proposed incorporates a greedy heuristic to find good initial solutions. These solutions, as well as the solutions later obtained through the use of the GA, go then through a repair procedure. This is used with two objectives, which are addressed in turn. Firstly, it checks the solution feasibility and if unfeasible it is fixed by removing some shows. Secondly, it tries to improve the solution by adding some extra shows. Since the problem faced by the commercial TV station is too big and has too many features it cannot be solved exactly. Therefore, in order to test the quality of the solutions provided by the proposed GA we have randomly generated some smaller problem instances. For these problems we have obtained solutions on average within 1% of the optimal solution value.

  13. Neural Meta-Memes Framework for Combinatorial Optimization

    NASA Astrophysics Data System (ADS)

    Song, Li Qin; Lim, Meng Hiot; Ong, Yew Soon

    In this paper, we present a Neural Meta-Memes Framework (NMMF) for combinatorial optimization. NMMF is a framework which models basic optimization algorithms as memes and manages them dynamically when solving combinatorial problems. NMMF encompasses neural networks which serve as the overall planner/coordinator to balance the workload between memes. We show the efficacy of the proposed NMMF through empirical study on a class of combinatorial problem, the quadratic assignment problem (QAP).

  14. Principles for problem aggregation and assignment in medium scale multiprocessors

    NASA Technical Reports Server (NTRS)

    Nicol, David M.; Saltz, Joel H.

    1987-01-01

    One of the most important issues in parallel processing is the mapping of workload to processors. This paper considers a large class of problems having a high degree of potential fine grained parallelism, and execution requirements that are either not predictable, or are too costly to predict. The main issues in mapping such a problem onto medium scale multiprocessors are those of aggregation and assignment. We study a method of parameterized aggregation that makes few assumptions about the workload. The mapping of aggregate units of work onto processors is uniform, and exploits locality of workload intensity to balance the unknown workload. In general, a finer aggregate granularity leads to a better balance at the price of increased communication/synchronization costs; the aggregation parameters can be adjusted to find a reasonable granularity. The effectiveness of this scheme is demonstrated on three model problems: an adaptive one-dimensional fluid dynamics problem with message passing, a sparse triangular linear system solver on both a shared memory and a message-passing machine, and a two-dimensional time-driven battlefield simulation employing message passing. Using the model problems, the tradeoffs are studied between balanced workload and the communication/synchronization costs. Finally, an analytical model is used to explain why the method balances workload and minimizes the variance in system behavior.

  15. The adaptive approach for storage assignment by mining data of warehouse management system for distribution centres

    NASA Astrophysics Data System (ADS)

    Ming-Huang Chiang, David; Lin, Chia-Ping; Chen, Mu-Chen

    2011-05-01

    Among distribution centre operations, order picking has been reported to be the most labour-intensive activity. Sophisticated storage assignment policies adopted to reduce the travel distance of order picking have been explored in the literature. Unfortunately, previous research has been devoted to locating entire products from scratch. Instead, this study intends to propose an adaptive approach, a Data Mining-based Storage Assignment approach (DMSA), to find the optimal storage assignment for newly delivered products that need to be put away when there is vacant shelf space in a distribution centre. In the DMSA, a new association index (AIX) is developed to evaluate the fitness between the put away products and the unassigned storage locations by applying association rule mining. With AIX, the storage location assignment problem (SLAP) can be formulated and solved as a binary integer programming. To evaluate the performance of DMSA, a real-world order database of a distribution centre is obtained and used to compare the results from DMSA with a random assignment approach. It turns out that DMSA outperforms random assignment as the number of put away products and the proportion of put away products with high turnover rates increase.

  16. 78 FR 6804 - Codex Alimentarius Commission: Meeting of the Codex Committee on Food Labeling

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-31

    ...; (c) Studying specific labeling problems assigned to it by Codex; and (d) Studying problems associated... the Production, Processing, Labeling and Marketing of Organically Produced Foods. (a) Use of ethylene... Washington, DC on January 24, 2013. Mary Frances Lowe, U.S. Manager for Codex Alimentarius. [FR Doc. 2013...

  17. Recalling Prerequisite Material in a Calculus II Course to Improve Student Success

    ERIC Educational Resources Information Center

    Mokry, Jeanette

    2016-01-01

    This article discusses preparation assignments used in a Calculus II course that cover material from prerequisite courses. Prior to learning new material, students work on problems outside of class involving concepts from algebra, trigonometry, and Calculus I. These problems are directly built upon in order to answer Calculus II questions,…

  18. Concordancers and Dictionaries as Problem-Solving Tools for ESL Academic Writing

    ERIC Educational Resources Information Center

    Yoon, Choongil

    2016-01-01

    The present study investigated how 6 Korean ESL graduate students in Canada used a suite of freely available reference resources, consisting of Web-based corpus tools, Google search engines, and dictionaries, for solving linguistic problems while completing an authentic academic writing assignment in English. Using a mixed methods design, the…

  19. Meanings Given to Algebraic Symbolism in Problem-Posing

    ERIC Educational Resources Information Center

    Cañadas, María C.; Molina, Marta; del Río, Aurora

    2018-01-01

    Some errors in the learning of algebra suggest that students might have difficulties giving meaning to algebraic symbolism. In this paper, we use problem posing to analyze the students' capacity to assign meaning to algebraic symbolism and the difficulties that students encounter in this process, depending on the characteristics of the algebraic…

  20. Comparison of Family Therapy Outcome with Alcohol-Abusing, Runaway Adolescents

    ERIC Educational Resources Information Center

    Slesnick, Natasha; Prestopnik, Jillian L

    2009-01-01

    Treatment evaluation for alcohol problem, runaway adolescents and their families is rare. This study recruited primary alcohol problem adolescents (N = 119) and their primary caretakers from two runaway shelters and assigned them to (a) home-based ecologically based family therapy (EBFT), (b) office-based functional family therapy (FFT), or (c)…

  1. Effectiveness of Word Solving: Integrating Morphological Problem-Solving within Comprehension Instruction for Middle School Students

    ERIC Educational Resources Information Center

    Goodwin, Amanda P.

    2016-01-01

    This study explores the effectiveness of integrating morphological instruction within comprehension strategy instruction. Participants were 203 students (N = 117 fifth-grade; 86 sixth-grade) from four urban schools who were randomly assigned to the intervention (N = 110; morphological problem-solving within comprehension strategy instruction) or…

  2. Effect of Worked Examples on Mental Model Progression in a Computer-Based Simulation Learning Environment

    ERIC Educational Resources Information Center

    Darabi, Aubteen; Nelson, David W.; Meeker, Richard; Liang, Xinya; Boulware, Wilma

    2010-01-01

    In a diagnostic problem solving operation of a computer-simulated chemical plant, chemical engineering students were randomly assigned to two groups: one studying product-oriented worked examples, the other practicing conventional problem solving. Effects of these instructional strategies on the progression of learners' mental models were examined…

  3. Turning Teaching Upside Down

    ERIC Educational Resources Information Center

    Seeley, Cathy L.

    2017-01-01

    The traditional method of teaching math--showing students how to do a procedure, then assigning problems that require them to use that exact procedure--leads to adults who don't know how to approach problems that don't look like those in their math book. Seeley describes an alternative teaching method (upside-down teaching) in which teachers give…

  4. Results and Implications of a Problem-Solving Treatment Program for Obesity.

    ERIC Educational Resources Information Center

    Mahoney, B. K.; And Others

    Data are from a large scale experimental study which was designed to evaluate a multimethod problem solving approach to obesity. Obese adult volunteers (N=90) were randomly assigned to three groups: maximal treatment, minimal treatment, and no treatment control. In the two treatment groups, subjects were exposed to bibliographic material and…

  5. Evolution of Protein Lipograms: A Bioinformatics Problem

    ERIC Educational Resources Information Center

    White, Harold B., III; Dhurjati, Prasad

    2006-01-01

    A protein lacking one of the 20 common amino acids is a protein lipogram. This open-ended problem-based learning assignment deals with the evolution of proteins with biased amino acid composition. It has students query protein and metabolic databases to test the hypothesis that natural selection has reduced the frequency of each amino acid…

  6. Congestion patterns of electric vehicles with limited battery capacity.

    PubMed

    Jing, Wentao; Ramezani, Mohsen; An, Kun; Kim, Inhi

    2018-01-01

    The path choice behavior of battery electric vehicle (BEV) drivers is influenced by the lack of public charging stations, limited battery capacity, range anxiety and long battery charging time. This paper investigates the congestion/flow pattern captured by stochastic user equilibrium (SUE) traffic assignment problem in transportation networks with BEVs, where the BEV paths are restricted by their battery capacities. The BEV energy consumption is assumed to be a linear function of path length and path travel time, which addresses both path distance limit problem and road congestion effect. A mathematical programming model is proposed for the path-based SUE traffic assignment where the path cost is the sum of the corresponding link costs and a path specific out-of-energy penalty. We then apply the convergent Lagrangian dual method to transform the original problem into a concave maximization problem and develop a customized gradient projection algorithm to solve it. A column generation procedure is incorporated to generate the path set. Finally, two numerical examples are presented to demonstrate the applicability of the proposed model and the solution algorithm.

  7. Parent training plus contingency management for substance abusing families: A Complier Average Causal Effects (CACE) analysis*

    PubMed Central

    Stanger, Catherine; Ryan, Stacy R.; Fu, Hongyun; Budney, Alan J.

    2011-01-01

    Background Children of substance abusers are at risk for behavioral/emotional problems. To improve outcomes for these children, we developed and tested an intervention that integrated a novel contingency management (CM) program designed to enhance compliance with an empirically-validated parent training curriculum. CM provided incentives for daily monitoring of parenting and child behavior, completion of home practice assignments, and session attendance. Methods Forty-seven mothers with substance abuse or dependence were randomly assigned to parent training + incentives (PTI) or parent training without incentives (PT). Children were 55% male, ages 2-7 years. Results Homework completion and session attendance did not differ between PTI and PT mothers, but PTI mothers had higher rates of daily monitoring. PTI children had larger reductions in child externalizing problems in all models. Complier Average Causal Effects (CACE) analyses showed additional significant effects of PTI on child internalizing problems, parent problems and parenting. These effects were not significant in standard Intent-to-Treat analyses. Conclusion Results suggest our incentive program may offer a method for boosting outcomes. PMID:21466925

  8. Congestion patterns of electric vehicles with limited battery capacity

    PubMed Central

    2018-01-01

    The path choice behavior of battery electric vehicle (BEV) drivers is influenced by the lack of public charging stations, limited battery capacity, range anxiety and long battery charging time. This paper investigates the congestion/flow pattern captured by stochastic user equilibrium (SUE) traffic assignment problem in transportation networks with BEVs, where the BEV paths are restricted by their battery capacities. The BEV energy consumption is assumed to be a linear function of path length and path travel time, which addresses both path distance limit problem and road congestion effect. A mathematical programming model is proposed for the path-based SUE traffic assignment where the path cost is the sum of the corresponding link costs and a path specific out-of-energy penalty. We then apply the convergent Lagrangian dual method to transform the original problem into a concave maximization problem and develop a customized gradient projection algorithm to solve it. A column generation procedure is incorporated to generate the path set. Finally, two numerical examples are presented to demonstrate the applicability of the proposed model and the solution algorithm. PMID:29543875

  9. IMU-to-Segment Assignment and Orientation Alignment for the Lower Body Using Deep Learning

    PubMed Central

    2018-01-01

    Human body motion analysis based on wearable inertial measurement units (IMUs) receives a lot of attention from both the research community and the and industrial community. This is due to the significant role in, for instance, mobile health systems, sports and human computer interaction. In sensor based activity recognition, one of the major issues for obtaining reliable results is the sensor placement/assignment on the body. For inertial motion capture (joint kinematics estimation) and analysis, the IMU-to-segment (I2S) assignment and alignment are central issues to obtain biomechanical joint angles. Existing approaches for I2S assignment usually rely on hand crafted features and shallow classification approaches (e.g., support vector machines), with no agreement regarding the most suitable features for the assignment task. Moreover, estimating the complete orientation alignment of an IMU relative to the segment it is attached to using a machine learning approach has not been shown in literature so far. This is likely due to the high amount of training data that have to be recorded to suitably represent possible IMU alignment variations. In this work, we propose online approaches for solving the assignment and alignment tasks for an arbitrary amount of IMUs with respect to a biomechanical lower body model using a deep learning architecture and windows of 128 gyroscope and accelerometer data samples. For this, we combine convolutional neural networks (CNNs) for local filter learning with long-short-term memory (LSTM) recurrent networks as well as generalized recurrent units (GRUs) for learning time dynamic features. The assignment task is casted as a classification problem, while the alignment task is casted as a regression problem. In this framework, we demonstrate the feasibility of augmenting a limited amount of real IMU training data with simulated alignment variations and IMU data for improving the recognition/estimation accuracies. With the proposed approaches and final models we achieved 98.57% average accuracy over all segments for the I2S assignment task (100% when excluding left/right switches) and an average median angle error over all segments and axes of 2.91° for the I2S alignment task. PMID:29351262

  10. Estimation of sex-specific survival from capture-recapture data when sex is not always known

    USGS Publications Warehouse

    Nichols, J.D.; Kendall, W.L.; Hines, J.E.; Spendelow, J.A.

    2004-01-01

    Many animals lack obvious sexual dimorphism, making assignment of sex difficult even for observed or captured animals. For many such species it is possible to assign sex with certainty only at some occasions; for example, when they exhibit certain types of behavior. A common approach to handling this situation in capture-recapture studies has been to group capture histories into those of animals eventually identified as male and female and those for which sex was never known. Because group membership is dependent on the number of occasions at which an animal was caught or observed (known sex animals, on average, will have been observed at more occasions than unknown-sex animals), survival estimates for known-sex animals will be positively biased, and those for unknown animals will be negatively biased. In this paper, we develop capture-recapture models that incorporate sex ratio and sex assignment parameters that permit unbiased estimation in the face of this sampling problem. We demonstrate the magnitude of bias in the traditional capture-recapture approach to this sampling problem, and we explore properties of estimators from other ad hoc approaches. The model is then applied to capture-recapture data for adult Roseate Terns (Sterna dougallii) at Falkner Island, Connecticut, 1993-2002. Sex ratio among adults in this population favors females, and we tested the hypothesis that this population showed sex-specific differences in adult survival. Evidence was provided for higher survival of adult females than males, as predicted. We recommend use of this modeling approach for future capture-recapture studies in which sex cannot always be assigned to captured or observed animals. We also place this problem in the more general context of uncertainty in state classification in multistate capture-recapture models.

  11. Assessment of a novel group-centered testing schema in an upper-level undergraduate molecular biotechnology course.

    PubMed

    Srougi, Melissa C; Miller, Heather B; Witherow, D Scott; Carson, Susan

    2013-01-01

    Providing students with assignments that focus on critical thinking is an important part of their scientific and intellectual development. However, as class sizes increase, so does the grading burden, prohibiting many faculty from incorporating critical thinking assignments in the classroom. In an effort to continue to provide our students with meaningful critical thinking exercises, we implemented a novel group-centered, problem-based testing scheme. We wanted to assess how performing critical thinking problem sets as group work compares to performing the sets as individual work, in terms of student attitudes and learning outcomes. During two semesters of our recombinant DNA course, students had the same lecture material and similar assessments. In the Fall semester, student learning was assessed by two collaborative take-home exams, followed immediately by individual, closed-book in-class exams on the same content, as well as a final cumulative exam. Student teams on the take-home exams were instructor-assigned, and each team turned in one collaborative exam. In the Spring semester, the control group of students were required to turn in their own individual take-home exams, followed by the in-class exams and final cumulative exam. For the majority of students, learning outcomes were met, regardless of whether they worked in teams. In addition, collaborative learning was favorably received by students and grading was reduced for instructors. These data suggest that group-centered, problem-based learning is a useful model for achievement of student learning outcomes in courses where it would be infeasible to provide feedback on individual critical thinking assignments due to grading volume. Copyright © 2013 Wiley Periodicals, Inc.

  12. Faster than classical quantum algorithm for dense formulas of exact satisfiability and occupation problems

    NASA Astrophysics Data System (ADS)

    Mandrà, Salvatore; Giacomo Guerreschi, Gian; Aspuru-Guzik, Alán

    2016-07-01

    We present an exact quantum algorithm for solving the Exact Satisfiability problem, which belongs to the important NP-complete complexity class. The algorithm is based on an intuitive approach that can be divided into two parts: the first step consists in the identification and efficient characterization of a restricted subspace that contains all the valid assignments of the Exact Satisfiability; while the second part performs a quantum search in such restricted subspace. The quantum algorithm can be used either to find a valid assignment (or to certify that no solution exists) or to count the total number of valid assignments. The query complexities for the worst-case are respectively bounded by O(\\sqrt{{2}n-{M\\prime }}) and O({2}n-{M\\prime }), where n is the number of variables and {M}\\prime the number of linearly independent clauses. Remarkably, the proposed quantum algorithm results to be faster than any known exact classical algorithm to solve dense formulas of Exact Satisfiability. As a concrete application, we provide the worst-case complexity for the Hamiltonian cycle problem obtained after mapping it to a suitable Occupation problem. Specifically, we show that the time complexity for the proposed quantum algorithm is bounded by O({2}n/4) for 3-regular undirected graphs, where n is the number of nodes. The same worst-case complexity holds for (3,3)-regular bipartite graphs. As a reference, the current best classical algorithm has a (worst-case) running time bounded by O({2}31n/96). Finally, when compared to heuristic techniques for Exact Satisfiability problems, the proposed quantum algorithm is faster than the classical WalkSAT and Adiabatic Quantum Optimization for random instances with a density of constraints close to the satisfiability threshold, the regime in which instances are typically the hardest to solve. The proposed quantum algorithm can be straightforwardly extended to the generalized version of the Exact Satisfiability known as Occupation problem. The general version of the algorithm is presented and analyzed.

  13. A multi-period capacitated school location problem with modular equipment and closest assignment considerations

    NASA Astrophysics Data System (ADS)

    Delmelle, Eric M.; Thill, Jean-Claude; Peeters, Dominique; Thomas, Isabelle

    2014-07-01

    In rapidly growing urban areas, it is deemed vital to expand (or contract) an existing network of public facilities to meet anticipated changes in the level of demand. We present a multi-period capacitated median model for school network facility location planning that minimizes transportation costs, while functional costs are subject to a budget constraint. The proposed Vintage Flexible Capacitated Location Problem (ViFCLP) has the flexibility to account for a minimum school-age closing requirement, while the maximum capacity of each school can be adjusted by the addition of modular units. Non-closest assignments are controlled by the introduction of a parameter penalizing excess travel. The applicability of the ViFCLP is illustrated on a large US school system (Charlotte-Mecklenburg, North Carolina) where high school demand is expected to grow faster with distance to the city center. Higher school capacities and greater penalty on travel impedance parameter reduce the number of non-closest assignments. The proposed model is beneficial to policy makers seeking to improve the provision and efficiency of public services over a multi-period planning horizon.

  14. Cell transmission model of dynamic assignment for urban rail transit networks.

    PubMed

    Xu, Guangming; Zhao, Shuo; Shi, Feng; Zhang, Feilian

    2017-01-01

    For urban rail transit network, the space-time flow distribution can play an important role in evaluating and optimizing the space-time resource allocation. For obtaining the space-time flow distribution without the restriction of schedules, a dynamic assignment problem is proposed based on the concept of continuous transmission. To solve the dynamic assignment problem, the cell transmission model is built for urban rail transit networks. The priority principle, queuing process, capacity constraints and congestion effects are considered in the cell transmission mechanism. Then an efficient method is designed to solve the shortest path for an urban rail network, which decreases the computing cost for solving the cell transmission model. The instantaneous dynamic user optimal state can be reached with the method of successive average. Many evaluation indexes of passenger flow can be generated, to provide effective support for the optimization of train schedules and the capacity evaluation for urban rail transit network. Finally, the model and its potential application are demonstrated via two numerical experiments using a small-scale network and the Beijing Metro network.

  15. Being "SMART" About Adolescent Conduct Problems Prevention: Executing a SMART Pilot Study in a Juvenile Diversion Agency.

    PubMed

    August, Gerald J; Piehler, Timothy F; Bloomquist, Michael L

    2016-01-01

    The development of adaptive treatment strategies (ATS) represents the next step in innovating conduct problems prevention programs within a juvenile diversion context. Toward this goal, we present the theoretical rationale, associated methods, and anticipated challenges for a feasibility pilot study in preparation for implementing a full-scale SMART (i.e., sequential, multiple assignment, randomized trial) for conduct problems prevention. The role of a SMART design in constructing ATS is presented. The SMART feasibility pilot study includes a sample of 100 youth (13-17 years of age) identified by law enforcement as early stage offenders and referred for precourt juvenile diversion programming. Prior data on the sample population detail a high level of ethnic diversity and approximately equal representations of both genders. Within the SMART, youth and their families are first randomly assigned to one of two different brief-type evidence-based prevention programs, featuring parent-focused behavioral management or youth-focused strengths-building components. Youth who do not respond sufficiently to brief first-stage programming will be randomly assigned a second time to either an extended parent- or youth-focused second-stage programming. Measures of proximal intervention response and measures of potential candidate tailoring variables for developing ATS within this sample are detailed. Results of the described pilot study will include information regarding feasibility and acceptability of the SMART design. This information will be used to refine a subsequent full-scale SMART. The use of a SMART to develop ATS for prevention will increase the efficiency and effectiveness of prevention programing for youth with developing conduct problems.

  16. Client Contacts Improve Quality of Copywriting.

    ERIC Educational Resources Information Center

    McCann, Guy

    1988-01-01

    Discusses the advantages of using real-life clients for class assignments in copywriting courses. Presents suggestions for client sources and identifies possible problems which may be encountered. (MM)

  17. Fragment assignment in the cloud with eXpress-D

    PubMed Central

    2013-01-01

    Background Probabilistic assignment of ambiguously mapped fragments produced by high-throughput sequencing experiments has been demonstrated to greatly improve accuracy in the analysis of RNA-Seq and ChIP-Seq, and is an essential step in many other sequence census experiments. A maximum likelihood method using the expectation-maximization (EM) algorithm for optimization is commonly used to solve this problem. However, batch EM-based approaches do not scale well with the size of sequencing datasets, which have been increasing dramatically over the past few years. Thus, current approaches to fragment assignment rely on heuristics or approximations for tractability. Results We present an implementation of a distributed EM solution to the fragment assignment problem using Spark, a data analytics framework that can scale by leveraging compute clusters within datacenters–“the cloud”. We demonstrate that our implementation easily scales to billions of sequenced fragments, while providing the exact maximum likelihood assignment of ambiguous fragments. The accuracy of the method is shown to be an improvement over the most widely used tools available and can be run in a constant amount of time when cluster resources are scaled linearly with the amount of input data. Conclusions The cloud offers one solution for the difficulties faced in the analysis of massive high-thoughput sequencing data, which continue to grow rapidly. Researchers in bioinformatics must follow developments in distributed systems–such as new frameworks like Spark–for ways to port existing methods to the cloud and help them scale to the datasets of the future. Our software, eXpress-D, is freely available at: http://github.com/adarob/express-d. PMID:24314033

  18. A modeling of dynamic storage assignment for order picking in beverage warehousing with Drive-in Rack system

    NASA Astrophysics Data System (ADS)

    Hadi, M. Z.; Djatna, T.; Sugiarto

    2018-04-01

    This paper develops a dynamic storage assignment model to solve storage assignment problem (SAP) for beverages order picking in a drive-in rack warehousing system to determine the appropriate storage location and space for each beverage products dynamically so that the performance of the system can be improved. This study constructs a graph model to represent drive-in rack storage position then combine association rules mining, class-based storage policies and an arrangement rule algorithm to determine an appropriate storage location and arrangement of the product according to dynamic orders from customers. The performance of the proposed model is measured as rule adjacency accuracy, travel distance (for picking process) and probability a product become expiry using Last Come First Serve (LCFS) queue approach. Finally, the proposed model is implemented through computer simulation and compare the performance for different storage assignment methods as well. The result indicates that the proposed model outperforms other storage assignment methods.

  19. Protein assignments without peak lists using higher-order spectra.

    PubMed

    Benison, Gregory; Berkholz, Donald S; Barbar, Elisar

    2007-12-01

    Despite advances in automating the generation and manipulation of peak lists for assigning biomolecules, there are well-known advantages to working directly with spectra: the eye is still superior to computer algorithms when it comes to picking out peak relationships from contour plots in the presence of confounding factors such as noise, overlap, and spectral artifacts. Here, we present constructs called higher-order spectra for identifying, through direct visual examination, many of the same relationships typically identified by searching peak lists, making them another addition to the set of tools (alongside peak picking and automated assignment) that can be used to solve the assignment problem. The technique is useful for searching for correlated peaks in any spectrum type. Application of this technique to novel, complete sequential assignment of two proteins (AhpFn and IC74(84-143)) is demonstrated. The program "burrow-owl" for the generation and display of higher-order spectra is available at (http://sourceforge.net/projects/burrow-owl) or from the authors.

  20. Mixed pyruvate labeling enables backbone resonance assignment of large proteins using a single experiment.

    PubMed

    Robson, Scott A; Takeuchi, Koh; Boeszoermenyi, Andras; Coote, Paul W; Dubey, Abhinav; Hyberts, Sven; Wagner, Gerhard; Arthanari, Haribabu

    2018-01-24

    Backbone resonance assignment is a critical first step in the investigation of proteins by NMR. This is traditionally achieved with a standard set of experiments, most of which are not optimal for large proteins. Of these, HNCA is the most sensitive experiment that provides sequential correlations. However, this experiment suffers from chemical shift degeneracy problems during the assignment procedure. We present a strategy that increases the effective resolution of HNCA and enables near-complete resonance assignment using this single HNCA experiment. We utilize a combination of 2- 13 C and 3- 13 C pyruvate as the carbon source for isotope labeling, which suppresses the one bond ( 1 J αβ ) coupling providing enhanced resolution for the Cα resonance and amino acid-specific peak shapes that arise from the residual coupling. Using this approach, we can obtain near-complete (>85%) backbone resonance assignment of a 42 kDa protein using a single HNCA experiment.

  1. Longitudinal evaluation of the importance of homework assignment completion for the academic performance of middle school students with ADHD.

    PubMed

    Langberg, Joshua M; Dvorsky, Melissa R; Molitor, Stephen J; Bourchtein, Elizaveta; Eddy, Laura D; Smith, Zoe; Schultz, Brandon K; Evans, Steven W

    2016-04-01

    The primary goal of this study was to longitudinally evaluate the homework assignment completion patterns of middle school age adolescents with ADHD, their associations with academic performance, and malleable predictors of homework assignment completion. Analyses were conducted on a sample of 104 middle school students comprehensively diagnosed with ADHD and followed for 18 months. Multiple teachers for each student provided information about the percentage of homework assignments turned in at five separate time points and school grades were collected quarterly. Results showed that agreement between teachers with respect to students assignment completion was high, with an intraclass correlation of .879 at baseline. Students with ADHD were turning in an average of 12% fewer assignments each academic quarter in comparison to teacher-reported classroom averages. Regression analyses revealed a robust association between the percentage of assignments turned in at baseline and school grades 18 months later, even after controlling for baseline grades, achievement (reading and math), intelligence, family income, and race. Cross-lag analyses demonstrated that the association between assignment completion and grades was reciprocal, with assignment completion negatively impacting grades and low grades in turn being associated with decreased future homework completion. Parent ratings of homework materials management abilities at baseline significantly predicted the percentage of assignments turned in as reported by teachers 18 months later. These findings demonstrate that homework assignment completion problems are persistent across time and an important intervention target for adolescents with ADHD. Copyright © 2015 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

  2. Verification of a VRF Heat Pump Computer Model in EnergyPlus

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

    Nigusse, Bereket; Raustad, Richard

    2013-06-15

    This paper provides verification results of the EnergyPlus variable refrigerant flow (VRF) heat pump computer model using manufacturer's performance data. The paper provides an overview of the VRF model, presents the verification methodology, and discusses the results. The verification provides quantitative comparison of full and part-load performance to manufacturer's data in cooling-only and heating-only modes of operation. The VRF heat pump computer model uses dual range bi-quadratic performance curves to represent capacity and Energy Input Ratio (EIR) as a function of indoor and outdoor air temperatures, and dual range quadratic performance curves as a function of part-load-ratio for modeling part-loadmore » performance. These performance curves are generated directly from manufacturer's published performance data. The verification compared the simulation output directly to manufacturer's performance data, and found that the dual range equation fit VRF heat pump computer model predicts the manufacturer's performance data very well over a wide range of indoor and outdoor temperatures and part-load conditions. The predicted capacity and electric power deviations are comparbale to equation-fit HVAC computer models commonly used for packaged and split unitary HVAC equipment.« less

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

    Hoffman, Jason D.; Kirby, Brian J.; Kwon, Jihwan

    Interfaces between correlated complex oxides are promising avenues to realize new forms of magnetism that arise as a result of charge transfer, proximity effects, and locally broken symmetries. We report on the discovery of a noncollinear magnetic structure in superlattices of the ferromagnetic metallic oxide La 2/3Sr 1/3MnO 3 (LSMO) and the correlated metal LaNiO 3 (LNO). The exchange interaction between LSMO layers is mediated by the intervening LNO, such that the angle between the magnetization of neighboring LSMO layers varies in an oscillatory manner with the thickness of the LNO layer. The magnetic field, temperature, and spacer thickness dependencemore » of the noncollinear structure are inconsistent with the bilinear and biquadratic interactions that are used to model the magnetic structure in conventional metallic multilayers. A model that couples the LSMO layers to a helical spin state within the LNO fits the observed behavior. We propose that the spin-helix results from the interaction between a spatially varying spin susceptibility within the LNO and interfacial charge transfer that creates localized Ni 2+ states. In conclusion, our work suggests a new approach to engineering noncollinear spin textures in metallic oxide heterostructures.« less

  4. A microscopic solution to the magnetic detwinning mystery in EuFe2As2

    NASA Astrophysics Data System (ADS)

    Maiwald, J.; Mazin, I. I.; Nandi, S.; Xiao, Y.; Gegenwart, P.

    One of the greatest recent advances in studying nematic phenomena in Fe-based superconductors was the mechanical detwinning of the 122-family compounds. Unfortunately, these techniques generate considerable stress in the investigated samples, which contaminates the results. Recently, we observed that a minuscule magnetic field of the order of 0.1 T irreversibly and persistently detwins EuFe2As2, opening an entirely new avenue for addressing nematicity. However, further development was hindered by the absence of a microscopic theory explaining this magnetic detwinning. In fact, Eu2+ has zero orbital moment and does not couple to the lattice, and its exchange coupling with the Fe sublattice cancels by symmetry. Moreover, further increase of the field to 1 T leads to a reorientation of Fe domains, while even larger fields 10 T reorient the domains once again. We will present a new microscopic model, based on a sizable biquadratic coupling between the Fe 3 d and Eu 4 f moments. This model quantitatively explains our old and new magnetization and neutron diffraction data, thus removing the veil of mystery and finally opening the door to full-scale research into magnetic detwinning and nematicity in Fe-based superconductors.

  5. Finite element area and line integral transforms for generalization of aperture function and geometry in Kirchhoff scalar diffraction theory

    NASA Astrophysics Data System (ADS)

    Kraus, Hal G.

    1993-02-01

    Two finite element-based methods for calculating Fresnel region and near-field region intensities resulting from diffraction of light by two-dimensional apertures are presented. The first is derived using the Kirchhoff area diffraction integral and the second is derived using a displaced vector potential to achieve a line integral transformation. The specific form of each of these formulations is presented for incident spherical waves and for Gaussian laser beams. The geometry of the two-dimensional diffracting aperture(s) is based on biquadratic isoparametric elements, which are used to define apertures of complex geometry. These elements are also used to build complex amplitude and phase functions across the aperture(s), which may be of continuous or discontinuous form. The finite element transform integrals are accurately and efficiently integrated numerically using Gaussian quadrature. The power of these methods is illustrated in several examples which include secondary obstructions, secondary spider supports, multiple mirror arrays, synthetic aperture arrays, apertures covered by screens, apodization, phase plates, and off-axis apertures. Typically, the finite element line integral transform results in significant gains in computational efficiency over the finite element Kirchhoff transform method, but is also subject to some loss in generality.

  6. Quantum spin chains with multiple dynamics

    NASA Astrophysics Data System (ADS)

    Chen, Xiao; Fradkin, Eduardo; Witczak-Krempa, William

    2017-11-01

    Many-body systems with multiple emergent time scales arise in various contexts, including classical critical systems, correlated quantum materials, and ultracold atoms. We investigate such nontrivial quantum dynamics in a different setting: a spin-1 bilinear-biquadratic chain. It has a solvable entangled ground state, but a gapless excitation spectrum that is poorly understood. By using large-scale density matrix renormalization group simulations, we find that the lowest excitations have a dynamical exponent z that varies from 2 to 3.2 as we vary a coupling in the Hamiltonian. We find an additional gapless mode with a continuously varying exponent 2 ≤z <2.7 , which establishes the presence of multiple dynamics. In order to explain these striking properties, we construct a continuum wave function for the ground state, which correctly describes the correlations and entanglement properties. We also give a continuum parent Hamiltonian, but show that additional ingredients are needed to capture the excitations of the chain. By using an exact mapping to the nonequilibrium dynamics of a classical spin chain, we find that the large dynamical exponent is due to subdiffusive spin motion. Finally, we discuss the connections to other spin chains and to a family of quantum critical models in two dimensions.

  7. Oscillatory noncollinear magnetism induced by interfacial charge transfer in superlattices composed of metallic oxides

    DOE PAGES

    Hoffman, Jason D.; Kirby, Brian J.; Kwon, Jihwan; ...

    2016-11-22

    Interfaces between correlated complex oxides are promising avenues to realize new forms of magnetism that arise as a result of charge transfer, proximity effects, and locally broken symmetries. We report on the discovery of a noncollinear magnetic structure in superlattices of the ferromagnetic metallic oxide La 2/3Sr 1/3MnO 3 (LSMO) and the correlated metal LaNiO 3 (LNO). The exchange interaction between LSMO layers is mediated by the intervening LNO, such that the angle between the magnetization of neighboring LSMO layers varies in an oscillatory manner with the thickness of the LNO layer. The magnetic field, temperature, and spacer thickness dependencemore » of the noncollinear structure are inconsistent with the bilinear and biquadratic interactions that are used to model the magnetic structure in conventional metallic multilayers. A model that couples the LSMO layers to a helical spin state within the LNO fits the observed behavior. We propose that the spin-helix results from the interaction between a spatially varying spin susceptibility within the LNO and interfacial charge transfer that creates localized Ni 2+ states. In conclusion, our work suggests a new approach to engineering noncollinear spin textures in metallic oxide heterostructures.« less

  8. Enhancement of electrical transport modulation in epitaxial VO2 nanowire field-effect transistor

    NASA Astrophysics Data System (ADS)

    Tanaka, Hidekazu; Chikanari, Masashi; Kanki, Teruo

    Strongly correlated system vanadium dioxide VO2 has attracted widespread concerns from researchers as an exciting electronic material, due to the many intriguing features, especially metal-insulator transition (MIT) in vicinity of room temperature. In this work, we report a diverse geometry for high sensitivity in the transport modulation. By taking advantage of nanometer scale channel, instead of thin film channels, we demonstrated the enhancement of resistance modulation by applying gate voltage. Also we designed the insulating gate, consisting of high-k material Ta2O5/organic polymer parylene-C hybrid insulator. Such as this hybrid gate dielectric would effectively reduce interface deterioration of active channel oxide and provide sufficient carrier density. Moreover, benefited from the nanometer scale channel, the VO2 nanowire-based transistor could deliver a resistance modulation ratio over 8.5%, which are about 10 folds higher than that of the film case. Furthermore, this result is explained that in spite of the stronger field distribution in the edge parts of VO2 nanowire channel yielded little carrier density, the generated mobility modulation would biquadratic increase according to Brinkman-Rice picture as new finding.

  9. On three dimensional object recognition and pose-determination: An abstraction based approach. Ph.D. Thesis - Michigan Univ. Final Report

    NASA Technical Reports Server (NTRS)

    Quek, Kok How Francis

    1990-01-01

    A method of computing reliable Gaussian and mean curvature sign-map descriptors from the polynomial approximation of surfaces was demonstrated. Such descriptors which are invariant under perspective variation are suitable for hypothesis generation. A means for determining the pose of constructed geometric forms whose algebraic surface descriptors are nonlinear in terms of their orienting parameters was developed. This was done by means of linear functions which are capable of approximating nonlinear forms and determining their parameters. It was shown that biquadratic surfaces are suitable companion linear forms for cylindrical approximation and parameter estimation. The estimates provided the initial parametric approximations necessary for a nonlinear regression stage to fine tune the estimates by fitting the actual nonlinear form to the data. A hypothesis-based split-merge algorithm for extraction and pose determination of cylinders and planes which merge smoothly into other surfaces was developed. It was shown that all split-merge algorithms are hypothesis-based. A finite-state algorithm for the extraction of the boundaries of run-length regions was developed. The computation takes advantage of the run list topology and boundary direction constraints implicit in the run-length encoding.

  10. A Geographic Optimization Approach to Coast Guard Ship Basing

    DTIC Science & Technology

    2015-06-01

    information found an optimal result for partition- ing. Carlsson applies the travelling salesman problem (tries to find the shortest path to visit a list of...maximum 200 words) This thesis studies the problem of finding efficient ship base locations, area of operations (AO) among bases, and ship assignments...for a coast guard (CG) organization. This problem is faced by many CGs around the world and is motivated by the need to optimize operational outcomes

  11. Flippin' Fluid Mechanics - Using Online Technology to Enhance the In-Class Learning Experience

    NASA Astrophysics Data System (ADS)

    Webster, D. R.; Majerich, D. M.

    2013-11-01

    This study provides an empirical analysis of using online technologies and team problem solving sessions to shift an undergraduate fluid mechanics course from a traditional lecture format to a collaborative learning environment. Students were from two consecutive semesters of the same course taught by the same professor. One group used online technologies and solved problems in class and the other did not. Out of class, the treatment group watched 72 short (11 minutes, average) video lectures covering course topics and example problems being solved. Three times a week students worked in teams of two to solve problems on desktop whiteboard tablets while the instructor and graduate assistants provided ``just-in-time'' tutoring. The number of team problems assigned during the semester exceeded 100. Weekly online homework was assigned to reinforce topics. The WileyPlus online system generated unique problem parameters for each student. The control group received three-50 minute weekly lectures. Data include three midterms and a final exam. Regression results indicate that controlling for all of the entered variables, for every one more problem solving session the student attended, the final grade was raised by 0.327 points. Thus, if a student participated in all 25 of the team problem solving sessions, the final grade would have been 8.2 points higher, a difference of nearly a grade. Using online technologies and teamwork appeared to result in improved achievement, but more research is needed to support these findings.

  12. Desire or Disease? Framing Obesity to Influence Attributions of Responsibility and Policy Support.

    PubMed

    McGlynn, Joseph; McGlone, Matthew S

    2018-02-01

    The way we describe health threats affects perceptions of severity and preferred solutions to reduce risk. Most people agree obesity is a problem, but differ in how they attribute responsibility for development and decline of the disease. We explored effects of message framing on attributions of responsibility and support for public obesity policies using a 3 × 2 factorial design. Participants read one of six versions of a health message describing the negative effects of obesity. Message frames influenced respondent attributions and their support for policies to reduce obesity. Those who read a message that assigned agency to the disease (e.g., Obesity causes health problems) endorsed genetics as the cause to a greater degree than those who read a semantically equivalent message that instead assigned agency to people (e.g., Obese people develop health problems). In contrast, assigning agency to people rather than to the disease prompted higher attributions of individual responsibility and support for public policies. Explicit message frames that directly connected responsibility for obesity to either individual or societal factors had no effect on respondent perceptions. Findings suggest explicit arguments may be less effective in shifting perceptions of health threats than arguments embedded in agentic message frames. The results demonstrate specific message features that influence how people attribute responsibility for the onset and solution of obesity.

  13. Future aircraft networks and schedules

    NASA Astrophysics Data System (ADS)

    Shu, Yan

    2011-07-01

    Because of the importance of air transportation scheduling, the emergence of small aircraft and the vision of future fuel-efficient aircraft, this thesis has focused on the study of aircraft scheduling and network design involving multiple types of aircraft and flight services. It develops models and solution algorithms for the schedule design problem and analyzes the computational results. First, based on the current development of small aircraft and on-demand flight services, this thesis expands a business model for integrating on-demand flight services with the traditional scheduled flight services. This thesis proposes a three-step approach to the design of aircraft schedules and networks from scratch under the model. In the first step, both a frequency assignment model for scheduled flights that incorporates a passenger path choice model and a frequency assignment model for on-demand flights that incorporates a passenger mode choice model are created. In the second step, a rough fleet assignment model that determines a set of flight legs, each of which is assigned an aircraft type and a rough departure time is constructed. In the third step, a timetable model that determines an exact departure time for each flight leg is developed. Based on the models proposed in the three steps, this thesis creates schedule design instances that involve almost all the major airports and markets in the United States. The instances of the frequency assignment model created in this thesis are large-scale non-convex mixed-integer programming problems, and this dissertation develops an overall network structure and proposes iterative algorithms for solving these instances. The instances of both the rough fleet assignment model and the timetable model created in this thesis are large-scale mixed-integer programming problems, and this dissertation develops subproblem schemes for solving these instances. Based on these solution algorithms, this dissertation also presents computational results of these large-scale instances. To validate the models and solution algorithms developed, this thesis also compares the daily flight schedules that it designs with the schedules of the existing airlines. Furthermore, it creates instances that represent different economic and fuel-prices conditions and derives schedules under these different conditions. In addition, it discusses the implication of using new aircraft in the future flight schedules. Finally, future research in three areas---model, computational method, and simulation for validation---is proposed.

  14. Deep Learning in Intermediate Microeconomics: Using Scaffolding Assignments to Teach Theory and Promote Transfer

    ERIC Educational Resources Information Center

    Green, Gareth P.; Bean, John C.; Peterson, Dean J.

    2013-01-01

    Intermediate microeconomics is typically viewed as a theory and tools course that relies on algorithmic problems to help students learn and apply economic theory. However, the authors' assessment research suggests that algorithmic problems by themselves do not encourage students to think about where the theory comes from, why the theory is…

  15. Investigating the Effect of Complexity Factors in Gas Law Problems

    ERIC Educational Resources Information Center

    Schuttlefield, Jennifer D.; Kirk, John; Pienta, Norbert J.; Tang, Hui

    2012-01-01

    Undergraduate students were asked to complete gas law questions using a Web-based tool as a first step in our understanding of the role of cognitive load in chemistry word questions and in helping us assess student problem-solving. Each question contained five different complexity factors, which were randomly assigned by the tool so that a…

  16. Adaptive Comparative Judgment as a Tool for Assessing Open-Ended Design Problems and Model Eliciting Activities

    ERIC Educational Resources Information Center

    Bartholomew, Scott R.; Nadelson, Louis S.; Goodridge, Wade H.; Reeve, Edward M.

    2018-01-01

    We investigated the use of adaptive comparative judgment to evaluate the middle school student learning, engagement, and experience with the design process in an open-ended problem assigned in a technology and engineering education course. Our results indicate that the adaptive comparative judgment tool effectively facilitated the grading of the…

  17. Following the Wrong Footsteps: Fixation Effects of Pictorial Examples in a Design Problem-Solving Task

    ERIC Educational Resources Information Center

    Chrysikou, Evangelia G.; Weisberg, Robert W.

    2005-01-01

    Two experiments examined possible negative transfer in nonexperts from the use of pictorial examples in a laboratory design problem-solving situation. In Experiment 1, 89 participants were instructed to "think aloud" and were assigned to 1 of 3 conditions: (a) control (standard instructions), (b) fixation (inclusion of a problematic…

  18. A Case Study for Teaching Quantitative Biochemical Buffer Problems Using Group Work and "Khan Style" Videos

    ERIC Educational Resources Information Center

    Barreto, Jose; Reilly, John; Brown, David; Frost. Laura; Coticone, Sulekha Rao; Dubetz, Terry Ann; Beharry, Zanna; Davis-McGibony, C. Michele; Ramoutar, Ria; Rudd, Gillian

    2014-01-01

    New technological developments have minimized training, hardware expense, and distribution problems for the production and use of instructional videos, and any science instructor can now make instructional videos for their classes. We created short "Khan style" videos for the topic of buffers in biochemistry and assigned them as…

  19. Proportional Reasoning Word Problem Performance for Middle School Students with High-Incidence Disabilities (HID)

    ERIC Educational Resources Information Center

    Brawand, Anne Eichorn

    2013-01-01

    Schema-based instruction (SBI) was used to examine the solving of proportional reasoning word problems for middle school students with high-incidence disabilities (HID). Seventh- and eighth-grade students with HID participated in the study. Students were randomly assigned to one of three groups. A multiple-baseline-across-groups design was…

  20. Achievement of Joint Perception in a Computer Supported Collaborative Learning Environment: A Case Study

    ERIC Educational Resources Information Center

    Afacan Adanir, Gulgun

    2017-01-01

    The case study focuses on the interactional mechanisms through which online collaborative teams co-construct a shared understanding of an analytical geometry problem by using dynamic geometry representations. The collaborative study consisted of an assignment on which the learners worked together in groups to solve a ship navigation problem as…

  1. Point of View: Ethics in the Classroom--Morality and the Laws of Thermodynamics.

    ERIC Educational Resources Information Center

    Saperstein, Alvin M.

    1982-01-01

    The first/second laws of thermodynamics are usually presented as straight physics. Local problems (such as heat engines) may be assigned but seldom is any effort made to examine universal human problems. Considering moral implications of these laws makes them relevant to students, gaining their attention and easing instruction. (Author/JN)

  2. A Quantitative Comparison of the Relative Performance of VHF and UHF Broadcast Systems. Technical Monograph Number 1.

    ERIC Educational Resources Information Center

    Rubin, Philip A.; And Others

    A study was undertaken to: (1) assess problems with UHF television systems; and (2) identify problem-solving activities on which different broadcast institutions could cooperate, The model for comparing UHF with VHF broadcast/reception services assigned performance disparity figures to each of the following elements: (1) transmitter and…

  3. Learning by Preparing to Teach: Fostering Self-Regulatory Processes and Achievement during Complex Mathematics Problem Solving

    ERIC Educational Resources Information Center

    Muis, Krista R.; Psaradellis, Cynthia; Chevrier, Marianne; Di Leo, Ivana; Lajoie, Susanne P.

    2016-01-01

    We developed an intervention based on the learning by teaching paradigm to foster self-regulatory processes and better learning outcomes during complex mathematics problem solving in a technology-rich learning environment. Seventy-eight elementary students were randomly assigned to 1 of 2 conditions: learning by preparing to teach, or learning for…

  4. Effects of Meaningfulness and Context on Information Processing in Third-Graders.

    ERIC Educational Resources Information Center

    Montgomery, Theresa; Richman, Shanna

    The effects of meaningfulness of the stimulus materials and the presence or absence of contextual cues on problem-solving behavior were investigated. Third-graders (N=80) were randomly assigned to one of four conditions and their performance in a series of discrimination problems was observed. Subjects in Conditions I and II responded to stimuli…

  5. Causal Inference and Omitted Variable Bias in Financial Aid Research: Assessing Solutions

    ERIC Educational Resources Information Center

    Riegg, Stephanie K.

    2008-01-01

    This article highlights the problem of omitted variable bias in research on the causal effect of financial aid on college-going. I first describe the problem of self-selection and the resulting bias from omitted variables. I then assess and explore the strengths and weaknesses of random assignment, multivariate regression, proxy variables, fixed…

  6. What Do Employers Pay for Employees' Complex Problem Solving Skills?

    ERIC Educational Resources Information Center

    Ederer, Peer; Nedelkoska, Ljubica; Patt, Alexander; Castellazzi, Silvia

    2015-01-01

    We estimate the market value that employers assign to the complex problem solving (CPS) skills of their employees, using individual-level Mincer-style wage regressions. For the purpose of the study, we collected new and unique data using psychometric measures of CPS and an extensive background questionnaire on employees' personal and work history.…

  7. Self-Management of On-Task Homework Behavior: A Promising Strategy for Adolescents with Attention and Behavior Problems

    ERIC Educational Resources Information Center

    Axelrod, Michael I.; Zhe, Elizabeth J.; Haugen, Kimberly A.; Klein, Jean A.

    2009-01-01

    Students with attention and behavior problems oftentimes experience difficulty finishing academic work. On-task behavior is frequently cited as a primary reason for students' failure to complete homework assignments. Researchers have identified self-monitoring and self-management of on-task behavior as effective tools for improving homework…

  8. Parent-Reported Homework Problems in the MTA Study: Evidence for Sustained Improvement with Behavioral Treatment

    ERIC Educational Resources Information Center

    Langberg, Joshua M.; Arnold, L. Eugene; Flowers, Amanda M.; Epstein, Jeffery N.; Altaye, Mekibib; Hinshaw, Stephen P.; Swanson, James M.; Kotkin, Ronald; Simpson, Stephen; Molina, Brooke S. G.; Jensen, Peter S.; Abikoff, Howard; Pelham, William E., Jr.; Vitiello, Benedetto; Wells, Karen C.; Hechtman, Lily

    2010-01-01

    Parent-report of child homework problems was examined as a treatment outcome variable in the MTA-Multimodal Treatment Study of Children with Attention-Deficit/Hyperactivity Disorder (ADHD). Five hundred seventy-nine children ages 7.0 to 9.9 were randomly assigned to either medication management, behavioral treatment, combination treatment, or…

  9. Case-Based Instruction in Post-Secondary Education: Developing Students' Problem-Solving Expertise.

    ERIC Educational Resources Information Center

    Ertmer, Peggy A.; Stepich, Donald A.

    This study was designed to explore changes in students' problem-solving skills as they analyzed instructional design case studies during a semester-long course. Nineteen students at two Midwestern universities analyzed six to ten case studies as part of their course assignments. Both quantitative and qualitative data were collected, with students'…

  10. Methodological Considerations in Evaluating School-Based Programs to Promote Social Competence and Reduce Problem Behavior

    ERIC Educational Resources Information Center

    Massetti, Greta M.; Crean, Hugh; Johnson, Deborah; DuBois, David; Ji, Peter

    2009-01-01

    Interventions that aim to promote social competence, reduce problem behavior, and improve school climate are common at all levels of schooling. This whole-school focus, coupled with researchers' concerns about contamination or spillover effects in evaluations that randomly assign classrooms or students to conditions, as well as advances in…

  11. Multipoint to multipoint routing and wavelength assignment in multi-domain optical networks

    NASA Astrophysics Data System (ADS)

    Qin, Panke; Wu, Jingru; Li, Xudong; Tang, Yongli

    2018-01-01

    In multi-point to multi-point (MP2MP) routing and wavelength assignment (RWA) problems, researchers usually assume the optical networks to be a single domain. However, the optical networks develop toward to multi-domain and larger scale in practice. In this context, multi-core shared tree (MST)-based MP2MP RWA are introduced problems including optimal multicast domain sequence selection, core nodes belonging in which domains and so on. In this letter, we focus on MST-based MP2MP RWA problems in multi-domain optical networks, mixed integer linear programming (MILP) formulations to optimally construct MP2MP multicast trees is presented. A heuristic algorithm base on network virtualization and weighted clustering algorithm (NV-WCA) is proposed. Simulation results show that, under different traffic patterns, the proposed algorithm achieves significant improvement on network resources occupation and multicast trees setup latency in contrast with the conventional algorithms which were proposed base on a single domain network environment.

  12. Guaranteed cost control with poles assignment for a flexible air-breathing hypersonic vehicle

    NASA Astrophysics Data System (ADS)

    Li, Hongyi; Si, Yulin; Wu, Ligang; Hu, Xiaoxiang; Gao, Huijun

    2011-05-01

    This article investigates the problem of guaranteed cost control for a flexible air-breathing hypersonic vehicle (FAHV). The FAHV includes intricate coupling between the engine and flight dynamics as well as complex interplay between flexible and rigid modes, which results in an intractable system for the control design. A longitudinal model is adopted for control design due to the complexity of the vehicle. First, for a highly nonlinear and coupled FAHV, a linearised model is established around the trim condition, which includes the state of altitude, velocity, angle of attack, pitch angle and pitch rate, etc. Secondly, by using the Lyapunov approach, performance analysis is carried out for the resulting closed-loop FAHV system, whose criterion with respect to guaranteed performance cost and poles assignment is expressed in the framework of linear matrix inequalities (LMIs). The established criterion exhibits a kind of decoupling between the Lyapunov positive-definite matrices to be determined and the FAHV system matrices, which is enabled by the introduction of additional slack matrix variables. Thirdly, a convex optimisation problem with LMI constraints is formulated for designing an admissible controller, which guarantees a prescribed performance cost with the simultaneous consideration of poles assignment for the resulting closed-loop system. Finally, some simulation results are provided to show that the guaranteed cost controller could assign the poles into the desired regional and achieve excellent reference altitude and velocity tracking performance.

  13. A Further Study of the Products of Sc and Dioxygen Reactions

    NASA Technical Reports Server (NTRS)

    Bauschlicher, Charles W., Jr.; Zhou, Mingfei; Andrews, Lester; Johnson, J. R. Tobias; Panas, Itai; Snis, Anders; Roos, Bjoern O.; Arnold, James O. (Technical Monitor)

    1999-01-01

    The products of the reaction of Sc and dioxygen have been reinvestigated. By adding the electron-trapping molecule CC14, additional information about the IR spectra has been obtained, as well as the observation of new bands. New ab initio calculations are also performed on possible products of the Sc plus O2 reaction. The previously observed band at 722.5 per cm is assigned as the b2 mode of ScO2(-). Bands arising from ScO(+), Sc(O2)(+), and(O2)ScO are also assigned. We are still unable to assign any bands to OScO. The problems associated with the computational study of ScO2 are discussed.

  14. Adaptive Control Strategies for Flexible Robotic Arm

    NASA Technical Reports Server (NTRS)

    Bialasiewicz, Jan T.

    1996-01-01

    The control problem of a flexible robotic arm has been investigated. The control strategies that have been developed have a wide application in approaching the general control problem of flexible space structures. The following control strategies have been developed and evaluated: neural self-tuning control algorithm, neural-network-based fuzzy logic control algorithm, and adaptive pole assignment algorithm. All of the above algorithms have been tested through computer simulation. In addition, the hardware implementation of a computer control system that controls the tip position of a flexible arm clamped on a rigid hub mounted directly on the vertical shaft of a dc motor, has been developed. An adaptive pole assignment algorithm has been applied to suppress vibrations of the described physical model of flexible robotic arm and has been successfully tested using this testbed.

  15. Scheduling of an aircraft fleet

    NASA Technical Reports Server (NTRS)

    Paltrinieri, Massimo; Momigliano, Alberto; Torquati, Franco

    1992-01-01

    Scheduling is the task of assigning resources to operations. When the resources are mobile vehicles, they describe routes through the served stations. To emphasize such aspect, this problem is usually referred to as the routing problem. In particular, if vehicles are aircraft and stations are airports, the problem is known as aircraft routing. This paper describes the solution to such a problem developed in OMAR (Operative Management of Aircraft Routing), a system implemented by Bull HN for Alitalia. In our approach, aircraft routing is viewed as a Constraint Satisfaction Problem. The solving strategy combines network consistency and tree search techniques.

  16. Soft and hard classification by reproducing kernel Hilbert space methods.

    PubMed

    Wahba, Grace

    2002-12-24

    Reproducing kernel Hilbert space (RKHS) methods provide a unified context for solving a wide variety of statistical modelling and function estimation problems. We consider two such problems: We are given a training set [yi, ti, i = 1, em leader, n], where yi is the response for the ith subject, and ti is a vector of attributes for this subject. The value of y(i) is a label that indicates which category it came from. For the first problem, we wish to build a model from the training set that assigns to each t in an attribute domain of interest an estimate of the probability pj(t) that a (future) subject with attribute vector t is in category j. The second problem is in some sense less ambitious; it is to build a model that assigns to each t a label, which classifies a future subject with that t into one of the categories or possibly "none of the above." The approach to the first of these two problems discussed here is a special case of what is known as penalized likelihood estimation. The approach to the second problem is known as the support vector machine. We also note some alternate but closely related approaches to the second problem. These approaches are all obtained as solutions to optimization problems in RKHS. Many other problems, in particular the solution of ill-posed inverse problems, can be obtained as solutions to optimization problems in RKHS and are mentioned in passing. We caution the reader that although a large literature exists in all of these topics, in this inaugural article we are selectively highlighting work of the author, former students, and other collaborators.

  17. Group Problem-Solving versus Lecture in College-Level Quantitative Analysis: The Good, the Bad, and the Ugly

    NASA Astrophysics Data System (ADS)

    Williamson, Vickie M.; Rowe, Marvin W.

    2002-09-01

    The purpose of this semester-long study was to investigate the effect of replacing traditional lecture with cooperative group problem-solving sessions in a junior-level quantitative analysis course. The control and treatment groups had the same instructor, met on the same day, had the same reading assignments, and had common exams. The instructor worked sample problems for the control group. In the treatment group, students were assigned to heterogeneous cooperative groups of 4. The groups solved problems presented on an overhead that were the same or equivalent in content and number to those used in the control group. Students were responsible for making sure that all members of the group could work each problem. The students' reasoning abilities were measured by the Test of Logical Thinking (TOLT). Groups were compared on quiz, exam, final, and course grades. Other data included attitudinal surveys, observations, field notes, interviews, and open-response evaluations. No significant differences were found in content measures. Differences were found in the number of students dropping the course and in the attitudes and perceptions of the two groups. Qualitative measures support a number of assertions concerning more positive attitudes and lower withdrawal rates in the treatment group, and a case for mixed delivery modes.

  18. Web-based Homework and Quiz Systems

    NASA Astrophysics Data System (ADS)

    Pritchard, David

    2005-05-01

    Mastering Physics is a Socratic tutor designed to help students learn introductory physics. The tutor poses problems and then comments specifically on about 1/2 of all wrong answers, even though most responses demanded are analytic expressions. Students can request hints (some of which are sub-problems), and work through the list of hint titles at random. In a typical problem there are 10 round trip interactions between tutor and student, raising the percentage of students who get the answer from ˜60% on the first try to over 90% after tutoring. This is Mastery Learning where student time and effort are increased to achieve learning rather than the grade decreased to indicate that the learning is incomplete. Mastering Physics is also a homework administration system that aids the instructor in preparing an assignment by indicating (in the problem library) the difficulty and duration of each problem and of the overall assignment. At MIT doing Mastering Physics has been shown to correlate much better than written homework or going to recitation with scoring better on the final exam in May than that student did on the final in December (which is why the student was repeating the course in the spring). At Arizona State, Mastering Physics increased the class' normalized gain on the Force Concept Inventory from 21% to 40% the year it was introduced.

  19. Exploring the Pareto frontier using multisexual evolutionary algorithms: an application to a flexible manufacturing problem

    NASA Astrophysics Data System (ADS)

    Bonissone, Stefano R.; Subbu, Raj

    2002-12-01

    In multi-objective optimization (MOO) problems we need to optimize many possibly conflicting objectives. For instance, in manufacturing planning we might want to minimize the cost and production time while maximizing the product's quality. We propose the use of evolutionary algorithms (EAs) to solve these problems. Solutions are represented as individuals in a population and are assigned scores according to a fitness function that determines their relative quality. Strong solutions are selected for reproduction, and pass their genetic material to the next generation. Weak solutions are removed from the population. The fitness function evaluates each solution and returns a related score. In MOO problems, this fitness function is vector-valued, i.e. it returns a value for each objective. Therefore, instead of a global optimum, we try to find the Pareto-optimal or non-dominated frontier. We use multi-sexual EAs with as many genders as optimization criteria. We have created new crossover and gender assignment functions, and experimented with various parameters to determine the best setting (yielding the highest number of non-dominated solutions.) These experiments are conducted using a variety of fitness functions, and the algorithms are later evaluated on a flexible manufacturing problem with total cost and time minimization objectives.

  20. Optimization of orbital assignment and specification of service areas in satellite communications

    NASA Technical Reports Server (NTRS)

    Wang, Cou-Way; Levis, Curt A.; Buyukdura, O. Merih

    1987-01-01

    The mathematical nature of the orbital and frequency assignment problem for communications satellites is explored, and it is shown that choosing the correct permutations of the orbit locations and frequency assignments is an important step in arriving at values which satisfy the signal-quality requirements. Two methods are proposed to achieve better spectrum/orbit utilization. The first, called the delta S concept, leads to orbital assignment solutions via either mixed-integer or restricted basis entry linear programming techniques; the method guarantees good single-entry carrier-to-interference ratio results. In the second, a basis for specifying service areas is proposed for the Fixed Satellite Service. It is suggested that service areas should be specified according to the communications-demand density in conjunction with the delta S concept in order to enable the system planner to specify more satellites and provide more communications supply.

  1. Development of a database for chemical mechanism assignments for volatile organic emissions.

    PubMed

    Carter, William P L

    2015-10-01

    The development of a database for making model species assignments when preparing total organic gas (TOG) emissions input for atmospheric models is described. This database currently has assignments of model species for 12 different gas-phase chemical mechanisms for over 1700 chemical compounds and covers over 3000 chemical categories used in five different anthropogenic TOG profile databases or output by two different biogenic emissions models. This involved developing a unified chemical classification system, assigning compounds to mixtures, assigning model species for the mechanisms to the compounds, and making assignments for unknown, unassigned, and nonvolatile mass. The comprehensiveness of the assignments, the contributions of various types of speciation categories to current profile and total emissions data, inconsistencies with existing undocumented model species assignments, and remaining speciation issues and areas of needed work are also discussed. The use of the system to prepare input for SMOKE, the Speciation Tool, and for biogenic models is described in the supplementary materials. The database, associated programs and files, and a users manual are available online at http://www.cert.ucr.edu/~carter/emitdb . Assigning air quality model species to the hundreds of emitted chemicals is a necessary link between emissions data and modeling effects of emissions on air quality. This is not easy and makes it difficult to implement new and more chemically detailed mechanisms in models. If done incorrectly, it is similar to errors in emissions speciation or the chemical mechanism used. Nevertheless, making such assignments is often an afterthought in chemical mechanism development and emissions processing, and existing assignments are usually undocumented and have errors and inconsistencies. This work is designed to address some of these problems.

  2. Manage Your Life Online (MYLO): a pilot trial of a conversational computer-based intervention for problem solving in a student sample.

    PubMed

    Gaffney, Hannah; Mansell, Warren; Edwards, Rachel; Wright, Jason

    2014-11-01

    Computerized self-help that has an interactive, conversational format holds several advantages, such as flexibility across presenting problems and ease of use. We designed a new program called MYLO that utilizes the principles of METHOD of Levels (MOL) therapy--based upon Perceptual Control Theory (PCT). We tested the efficacy of MYLO, tested whether the psychological change mechanisms described by PCT mediated its efficacy, and evaluated effects of client expectancy. Forty-eight student participants were randomly assigned to MYLO or a comparison program ELIZA. Participants discussed a problem they were currently experiencing with their assigned program and completed measures of distress, resolution and expectancy preintervention, postintervention and at 2-week follow-up. MYLO and ELIZA were associated with reductions in distress, depression, anxiety and stress. MYLO was considered more helpful and led to greater problem resolution. The psychological change processes predicted higher ratings of MYLO's helpfulness and reductions in distress. Positive expectancies towards computer-based problem solving correlated with MYLO's perceived helpfulness and greater problem resolution, and this was partly mediated by the psychological change processes identified. The findings provide provisional support for the acceptability of the MYLO program in a non-clinical sample although its efficacy as an innovative computer-based aid to problem solving remains unclear. Nevertheless, the findings provide tentative early support for the mechanisms of psychological change identified within PCT and highlight the importance of client expectations on predicting engagement in computer-based self-help.

  3. Using ant colony optimization on the quadratic assignment problem to achieve low energy cost in geo-distributed data centers

    NASA Astrophysics Data System (ADS)

    Osei, Richard

    There are many problems associated with operating a data center. Some of these problems include data security, system performance, increasing infrastructure complexity, increasing storage utilization, keeping up with data growth, and increasing energy costs. Energy cost differs by location, and at most locations fluctuates over time. The rising cost of energy makes it harder for data centers to function properly and provide a good quality of service. With reduced energy cost, data centers will have longer lasting servers/equipment, higher availability of resources, better quality of service, a greener environment, and reduced service and software costs for consumers. Some of the ways that data centers have tried to using to reduce energy costs include dynamically switching on and off servers based on the number of users and some predefined conditions, the use of environmental monitoring sensors, and the use of dynamic voltage and frequency scaling (DVFS), which enables processors to run at different combinations of frequencies with voltages to reduce energy cost. This thesis presents another method by which energy cost at data centers could be reduced. This method involves the use of Ant Colony Optimization (ACO) on a Quadratic Assignment Problem (QAP) in assigning user request to servers in geo-distributed data centers. In this paper, an effort to reduce data center energy cost involves the use of front portals, which handle users' requests, were used as ants to find cost effective ways to assign users requests to a server in heterogeneous geo-distributed data centers. The simulation results indicate that the ACO for Optimal Server Activation and Task Placement algorithm reduces energy cost on a small and large number of users' requests in a geo-distributed data center and its performance increases as the input data grows. In a simulation with 3 geo-distributed data centers, and user's resource request ranging from 25,000 to 25,000,000, the ACO algorithm was able to reduce energy cost on an average of $.70 per second. The ACO for Optimal Server Activation and Task Placement algorithm has proven to work as an alternative or improvement in reducing energy cost in geo-distributed data centers.

  4. Some approaches to optimal cluster labeling of aerospace imagery

    NASA Technical Reports Server (NTRS)

    Chittineni, C. B.

    1980-01-01

    Some approaches are presented to the problem of labeling clusters using information from a given set of labeled and unlabeled aerospace imagery patterns. The assignment of class labels to the clusters is formulated as the determination of the best assignment over all possible ones with respect to some criterion. Cluster labeling is also viewed as the probability of correct labeling with a maximization of likelihood function. Results of the application of these techniques in the processing of remotely sensed multispectral scanner imagery data are presented.

  5. An Improved Memetic Algorithm for Break Scheduling

    NASA Astrophysics Data System (ADS)

    Widl, Magdalena; Musliu, Nysret

    In this paper we consider solving a complex real life break scheduling problem. This problem of high practical relevance arises in many working areas, e.g. in air traffic control and other fields where supervision personnel is working. The objective is to assign breaks to employees such that various constraints reflecting legal demands or ergonomic criteria are satisfied and staffing requirement violations are minimised.

  6. Preventing Behavior Problems among Elementary Schoolchildren: Impact of a Universal School-Based Program in China

    ERIC Educational Resources Information Center

    Hong, Lin; Yufeng, Wang; Agho, Kingsley; Jacobs, Jennifer

    2011-01-01

    Background: To evaluate the effect on problem behaviors of a universal school-based prevention curriculum of third grade students. Methods: Six regular classes in 1 elementary school were randomly assigned to an intervention (n = 208) or control (n = 209) group. A 13-session program was offered to students in the intervention group. The Achenbach…

  7. Action Socialization Experiences at the New Jersey School of Conservation. Revised Fall 1977.

    ERIC Educational Resources Information Center

    Merritt, James K.

    The Action Socialization Experiences (ASE) presented in this guide are modified Outward Bound initiative tests developed at the New Jersey School of Conservation to be used as an introduction to group problem solving. The ASE process is described as follows: teachers are assigned a specific problem for a 2-hour period and briefed on techniques of…

  8. Experimental Evidence of the Relative Effectiveness of Problem-Based Learning for Knowledge Acquisition and Retention

    ERIC Educational Resources Information Center

    Wijnen, Marit; Loyens, Sofie M. M.; Schaap, Lydia

    2016-01-01

    This study investigated the effects of problem-based learning (PBL) on knowledge acquisition and knowledge retention in a controlled experiment in a lab setting. Eighty-eight first-year psychology students were randomly assigned to either a PBL condition, a lecture condition, or a self-study condition. All participants had the opportunity to study…

  9. Scalable Effective Approaches for Quadratic Assignment Problems Based on Conic Optimization and Applications

    DTIC Science & Technology

    2012-02-09

    1nclud1ng suggestions for reduc1ng the burden. to the Department of Defense. ExecutiVe Serv1ce D>rectorate (0704-0188) Respondents should be aware...benchmark problem we contacted Bertrand LeCun who in their poject CHOC from 2005-2008 had applied their parallel B&B framework BOB++ to the RLT1

  10. ModerateDrinking.com and Moderation Management: Outcomes of a Randomized Clinical Trial with Non-Dependent Problem Drinkers

    ERIC Educational Resources Information Center

    Hester, Reid K.; Delaney, Harold D.; Campbell, William

    2011-01-01

    Objective: To evaluate the effectiveness of a web-based protocol, ModerateDrinking.com (MD; "www.moderatedrinking.com") combined with use of the online resources of Moderation Management (MM; "www.moderation.org") as opposed to the use of the online resources of MM alone. Method: We randomly assigned 80 problem drinkers to…

  11. A Genetic Algorithm for the Bi-Level Topological Design of Local Area Networks

    PubMed Central

    Camacho-Vallejo, José-Fernando; Mar-Ortiz, Julio; López-Ramos, Francisco; Rodríguez, Ricardo Pedraza

    2015-01-01

    Local access networks (LAN) are commonly used as communication infrastructures which meet the demand of a set of users in the local environment. Usually these networks consist of several LAN segments connected by bridges. The topological LAN design bi-level problem consists on assigning users to clusters and the union of clusters by bridges in order to obtain a minimum response time network with minimum connection cost. Therefore, the decision of optimally assigning users to clusters will be made by the leader and the follower will make the decision of connecting all the clusters while forming a spanning tree. In this paper, we propose a genetic algorithm for solving the bi-level topological design of a Local Access Network. Our solution method considers the Stackelberg equilibrium to solve the bi-level problem. The Stackelberg-Genetic algorithm procedure deals with the fact that the follower’s problem cannot be optimally solved in a straightforward manner. The computational results obtained from two different sets of instances show that the performance of the developed algorithm is efficient and that it is more suitable for solving the bi-level problem than a previous Nash-Genetic approach. PMID:26102502

  12. An Airway Network Flow Assignment Approach Based on an Efficient Multiobjective Optimization Framework

    PubMed Central

    Zhang, Xuejun; Lei, Jiaxing

    2015-01-01

    Considering reducing the airspace congestion and the flight delay simultaneously, this paper formulates the airway network flow assignment (ANFA) problem as a multiobjective optimization model and presents a new multiobjective optimization framework to solve it. Firstly, an effective multi-island parallel evolution algorithm with multiple evolution populations is employed to improve the optimization capability. Secondly, the nondominated sorting genetic algorithm II is applied for each population. In addition, a cooperative coevolution algorithm is adapted to divide the ANFA problem into several low-dimensional biobjective optimization problems which are easier to deal with. Finally, in order to maintain the diversity of solutions and to avoid prematurity, a dynamic adjustment operator based on solution congestion degree is specifically designed for the ANFA problem. Simulation results using the real traffic data from China air route network and daily flight plans demonstrate that the proposed approach can improve the solution quality effectively, showing superiority to the existing approaches such as the multiobjective genetic algorithm, the well-known multiobjective evolutionary algorithm based on decomposition, and a cooperative coevolution multiobjective algorithm as well as other parallel evolution algorithms with different migration topology. PMID:26180840

  13. Solution of the determinantal assignment problem using the Grassmann matrices

    NASA Astrophysics Data System (ADS)

    Karcanias, Nicos; Leventides, John

    2016-02-01

    The paper provides a direct solution to the determinantal assignment problem (DAP) which unifies all frequency assignment problems of the linear control theory. The current approach is based on the solvability of the exterior equation ? where ? is an n -dimensional vector space over ? which is an integral part of the solution of DAP. New criteria for existence of solution and their computation based on the properties of structured matrices are referred to as Grassmann matrices. The solvability of this exterior equation is referred to as decomposability of ?, and it is in turn characterised by the set of quadratic Plücker relations (QPRs) describing the Grassmann variety of the corresponding projective space. Alternative new tests for decomposability of the multi-vector ? are given in terms of the rank properties of the Grassmann matrix, ? of the vector ?, which is constructed by the coordinates of ?. It is shown that the exterior equation is solvable (? is decomposable), if and only if ? where ?; the solution space for a decomposable ?, is the space ?. This provides an alternative linear algebra characterisation of the decomposability problem and of the Grassmann variety to that defined by the QPRs. Further properties of the Grassmann matrices are explored by defining the Hodge-Grassmann matrix as the dual of the Grassmann matrix. The connections of the Hodge-Grassmann matrix to the solution of exterior equations are examined, and an alternative new characterisation of decomposability is given in terms of the dimension of its image space. The framework based on the Grassmann matrices provides the means for the development of a new computational method for the solutions of the exact DAP (when such solutions exist), as well as computing approximate solutions, when exact solutions do not exist.

  14. Being “SMART” about Adolescent Conduct Problems Prevention: Executing a SMART Pilot Study in a Juvenile Diversion Agency

    PubMed Central

    August, Gerald J.; Piehler, Timothy F.; Bloomquist, Michael L.

    2014-01-01

    OBJECTIVE The development of adaptive treatment strategies (ATS) represents the next step in innovating conduct problems prevention programs within a juvenile diversion context. Towards this goal, we present the theoretical rationale, associated methods, and anticipated challenges for a feasibility pilot study in preparation for implementing a full-scale SMART (i.e., sequential, multiple assignment, randomized trial) for conduct problems prevention. The role of a SMART design in constructing ATS is presented. METHOD The SMART feasibility pilot study includes a sample of 100 youth (13–17 years of age) identified by law enforcement as early stage offenders and referred for pre-court juvenile diversion programming. Prior data on the sample population detail a high level of ethnic diversity and approximately equal representations of both genders. Within the SMART, youth and their families are first randomly assigned to one of two different brief-type evidence-based prevention programs, featuring parent-focused behavioral management or youth-focused strengths-building components. Youth who do not respond sufficiently to brief first-stage programming will be randomly assigned a second time to either an extended parent- or youth-focused second-stage programming. Measures of proximal intervention response and measures of potential candidate tailoring variables for developing ATS within this sample are detailed. RESULTS Results of the described pilot study will include information regarding feasibility and acceptability of the SMART design. This information will be used to refine a subsequent full-scale SMART. CONCLUSIONS The use of a SMART to develop ATS for prevention will increase the efficiency and effectiveness of prevention programing for youth with developing conduct problems. PMID:25256135

  15. Automation of NMR structure determination of proteins.

    PubMed

    Altieri, Amanda S; Byrd, R Andrew

    2004-10-01

    The automation of protein structure determination using NMR is coming of age. The tedious processes of resonance assignment, followed by assignment of NOE (nuclear Overhauser enhancement) interactions (now intertwined with structure calculation), assembly of input files for structure calculation, intermediate analyses of incorrect assignments and bad input data, and finally structure validation are all being automated with sophisticated software tools. The robustness of the different approaches continues to deal with problems of completeness and uniqueness; nevertheless, the future is very bright for automation of NMR structure generation to approach the levels found in X-ray crystallography. Currently, near completely automated structure determination is possible for small proteins, and the prospect for medium-sized and large proteins is good. Copyright 2004 Elsevier Ltd.

  16. Adaptive Discrete Hypergraph Matching.

    PubMed

    Yan, Junchi; Li, Changsheng; Li, Yin; Cao, Guitao

    2018-02-01

    This paper addresses the problem of hypergraph matching using higher-order affinity information. We propose a solver that iteratively updates the solution in the discrete domain by linear assignment approximation. The proposed method is guaranteed to converge to a stationary discrete solution and avoids the annealing procedure and ad-hoc post binarization step that are required in several previous methods. Specifically, we start with a simple iterative discrete gradient assignment solver. This solver can be trapped in an -circle sequence under moderate conditions, where is the order of the graph matching problem. We then devise an adaptive relaxation mechanism to jump out this degenerating case and show that the resulting new path will converge to a fixed solution in the discrete domain. The proposed method is tested on both synthetic and real-world benchmarks. The experimental results corroborate the efficacy of our method.

  17. Personal experience with the AEP Faculty Internship Program. [Conference paper

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

    Thorp, J.S.

    1980-01-01

    The American Electric Power (AEP) Faculty Intern Program allows a continuing association with the industry that has been beneficial to the power program at Cornell. The first necessary condition for a successful internship is than the intern be interested in power and willing to make a commitment to learning. A selection of a problem area that allows the intern to make significant contributions to the project is very important. A single assignment that spans a number of areas rather than a number of narrow assignments seems desirable. Supplemental training through course work and travel and working with excellent people inmore » an ideal environment enriches the internship. The continued consulting after the internship is more valuable even than the internship itself. Continued contact with current problems keeps the academic program relevant and maintains faculty enthusiasm.« less

  18. Does Head Start differentially benefit children with risks targeted by the program’s service model?☆

    PubMed Central

    Miller, Elizabeth B.; Farkas, George; Duncan, Greg J.

    2015-01-01

    Data from the Head Start Impact Study (N = 3540) were used to test for differential benefits of Head Start after one program year and after kindergarten on pre-academic and behavior outcomes for children at risk in the domains targeted by the program’s comprehensive services. Although random assignment to Head Start produced positive treatment main effects on children’s pre-academic skills and behavior problems, residualized growth models showed that random assignment to Head Start did not differentially benefit the pre-academic skills of children with risk factors targeted by the Head Start service model. The models showed detrimental impacts of Head Start for maternal-reported behavior problems of high-risk children, but slightly more positive impacts for teacher-reported behavior. Policy implications for Head Start are discussed. PMID:26379369

  19. Credit assignment in movement-dependent reinforcement learning

    PubMed Central

    Boggess, Matthew J.; Crossley, Matthew J.; Parvin, Darius; Ivry, Richard B.; Taylor, Jordan A.

    2016-01-01

    When a person fails to obtain an expected reward from an object in the environment, they face a credit assignment problem: Did the absence of reward reflect an extrinsic property of the environment or an intrinsic error in motor execution? To explore this problem, we modified a popular decision-making task used in studies of reinforcement learning, the two-armed bandit task. We compared a version in which choices were indicated by key presses, the standard response in such tasks, to a version in which the choices were indicated by reaching movements, which affords execution failures. In the key press condition, participants exhibited a strong risk aversion bias; strikingly, this bias reversed in the reaching condition. This result can be explained by a reinforcement model wherein movement errors influence decision-making, either by gating reward prediction errors or by modifying an implicit representation of motor competence. Two further experiments support the gating hypothesis. First, we used a condition in which we provided visual cues indicative of movement errors but informed the participants that trial outcomes were independent of their actual movements. The main result was replicated, indicating that the gating process is independent of participants’ explicit sense of control. Second, individuals with cerebellar degeneration failed to modulate their behavior between the key press and reach conditions, providing converging evidence of an implicit influence of movement error signals on reinforcement learning. These results provide a mechanistically tractable solution to the credit assignment problem. PMID:27247404

  20. Credit assignment in movement-dependent reinforcement learning.

    PubMed

    McDougle, Samuel D; Boggess, Matthew J; Crossley, Matthew J; Parvin, Darius; Ivry, Richard B; Taylor, Jordan A

    2016-06-14

    When a person fails to obtain an expected reward from an object in the environment, they face a credit assignment problem: Did the absence of reward reflect an extrinsic property of the environment or an intrinsic error in motor execution? To explore this problem, we modified a popular decision-making task used in studies of reinforcement learning, the two-armed bandit task. We compared a version in which choices were indicated by key presses, the standard response in such tasks, to a version in which the choices were indicated by reaching movements, which affords execution failures. In the key press condition, participants exhibited a strong risk aversion bias; strikingly, this bias reversed in the reaching condition. This result can be explained by a reinforcement model wherein movement errors influence decision-making, either by gating reward prediction errors or by modifying an implicit representation of motor competence. Two further experiments support the gating hypothesis. First, we used a condition in which we provided visual cues indicative of movement errors but informed the participants that trial outcomes were independent of their actual movements. The main result was replicated, indicating that the gating process is independent of participants' explicit sense of control. Second, individuals with cerebellar degeneration failed to modulate their behavior between the key press and reach conditions, providing converging evidence of an implicit influence of movement error signals on reinforcement learning. These results provide a mechanistically tractable solution to the credit assignment problem.

  1. Optimization techniques applied to spectrum management for communications satellites

    NASA Astrophysics Data System (ADS)

    Ottey, H. R.; Sullivan, T. M.; Zusman, F. S.

    This paper describes user requirements, algorithms and software design features for the application of optimization techniques to the management of the geostationary orbit/spectrum resource. Relevant problems include parameter sensitivity analyses, frequency and orbit position assignment coordination, and orbit position allotment planning. It is shown how integer and nonlinear programming as well as heuristic search techniques can be used to solve these problems. Formalized mathematical objective functions that define the problems are presented. Constraint functions that impart the necessary solution bounds are described. A versatile program structure is outlined, which would allow problems to be solved in stages while varying the problem space, solution resolution, objective function and constraints.

  2. Proposal for Land Consolidation Project Solutions for Selected Problem Areas

    NASA Astrophysics Data System (ADS)

    Wojcik-Len, Justyna; Strek, Zanna

    2017-12-01

    One of the economic tools for supporting agricultural policy are the activities implemented under the Rural Development Program (RDP). By encouraging agricultural activities and creating equal opportunities for development of farms, among others in areas with unfavourable environmental conditions characterized by low productivity of soils exposed to degradation, decision makers can contribute to improving the spatial structure of rural areas. In Poland, one of the major concerns are agricultural problem areas (regions). In view of this situation, the aim of this article was to characterize the problem areas in question and propose land consolidation project solutions for selected fragments of those areas. This paper presents the results of a review of literature and an analysis of geodetic and cartographic data regarding the problem areas. The process of land consolidation, which is one of the technical and legal instruments supporting the development of rural areas, was characterized. The study allowed the present authors to establish criteria for selecting agricultural problem areas for land consolidation. To develop a proposal for rational management of the problem areas, key general criteria (location, topography, soil quality and usefulness) and specific criteria were defined and assigned weights. A conception of alternative development of the agricultural problem areas was created as part of a land consolidation project. The results were used to create a methodology for the development of agricultural problem areas to be employed during land consolidation in rural areas. Every agricultural space includes areas with unfavourable environmental and soil conditions determined by natural or anthropogenic factors. Development of agricultural problem areas through land consolidation should take into account the specific functions assigned to these areas in land use plans, as well as to comply with legal regulations.

  3. Shifting senses in lexical semantic development

    PubMed Central

    Rabagliati, Hugh; Marcus, Gary F.; Pylkkänen, Liina

    2010-01-01

    Most words are associated with multiple senses. A DVD can be round (when describing a disc), and a DVD can be an hour long (when describing a movie), and in each case DVD means something different. The possible senses of a word are often predictable, and also constrained, as words cannot take just any meaning: for example, although a movie can be an hour long, it cannot sensibly be described as round (unlike a DVD). Learning the scope and limits of word meaning is vital for the comprehension of natural language, but poses a potentially difficult learnability problem for children. By testing what senses children are willing to assign to a variety of words, we demonstrate that, in comprehension, the problem is solved using a productive learning strategy. Children are perfectly capable of assigning different senses to a word; indeed they are essentially adult-like at assigning licensed meanings. But difficulties arise in determining which senses are assignable: children systematically overestimate the possible senses of a word, allowing meanings that adults rule unlicensed (e.g., taking round movie to refer to a disc). By contrast, this strategy does not extend to production, in which children use licensed, but not unlicensed, senses. Children’s productive comprehension strategy suggests an early emerging facility for using context in sense resolution (a difficult task for natural language processing algorithms), but leaves an intriguing question as to the mechanisms children use to learn a restricted, adult-like set of senses. PMID:20638655

  4. Evaluating an Electronic Plagiarism Detection Service: The Importance of Trust and the Difficulty of Proving Students Don't Cheat

    ERIC Educational Resources Information Center

    Evans, Robert

    2006-01-01

    Plagiarism by students is seen as an increasing problem. The fear is that students will use the internet to obtain analysis, interpretation or even complete assignments and then submit these as their own work. Electronic plagiarism detection services may help to prevent such unfair practice but, in doing so, they create a new problem: certifying…

  5. Who Benefits and How Does It Work? Moderators and Mediators of Outcome in an Effectiveness Trial of a Parenting Intervention

    ERIC Educational Resources Information Center

    Gardner, Frances; Hutchings, Judy; Bywater, Tracey; Whitaker, Chris

    2010-01-01

    We examined mediators and moderators of change in conduct problems, in a multiagency randomized trial of the Incredible Years parenting program. Preschoolers (n = 153) at risk for conduct problems were randomly assigned to intervention (n = 104) and wait-list (n = 49) groups. Boys and younger children, and those with more depressed mothers, tended…

  6. Impact of insects on multiple-use values of north-central forests: an experimental rating scheme.

    Treesearch

    Norton D. Addy; Harold O. Batzer; William J. Mattson; William E. Miller

    1971-01-01

    Ranking or assigning priorities to problems is an essential step in research problem selection. Up to now, no rigorous basis for ranking forest insects has been available. We evaluate and rank forest insects with a systematic numerical scheme that considers insect impact on the multiple-use values of timber, wildlife, recreation, and water. The result is a better...

  7. The Effects of Problem-Based Learning with Flipped Classroom on Elementary Students' Computing Skills: A Case Study of the Production of Ebooks

    ERIC Educational Resources Information Center

    Tsai, Chia-Wen; Shen, Pei-Di; Lu, Yu-Jui

    2015-01-01

    This study investigated, via quasi-experiments, the effects of problem-based learning with flipped classroom (FPBL) on the development of students' learning performance. In this study, 144 elementary school students were selected from sixth-grade sections taking a course titled "Production of Ebook," and were assigned into the following…

  8. Effects of Intervention to Improve At-Risk Fourth Graders' Understanding, Calculations, and Word Problems with Fractions

    ERIC Educational Resources Information Center

    Fuchs, Lynn S.; Schumacher, Robin F.; Long, Jessica; Namkung, Jessica; Malone, Amelia S.; Wang, Amber; Hamlett, Carol L.; Jordan, Nancy C.; Siegler, Robert S.; Changas, Paul

    2016-01-01

    The purposes of this study were to (a) investigate the efficacy of a core fraction intervention program on understanding and calculation skill and (b) isolate the effects of different forms of fraction word-problem (WP) intervention delivered as part of the larger program. At-risk 4th graders (n = 213) were randomly assigned at the individual…

  9. Effects of Intervention to Improve At-Risk Fourth Graders' Understanding, Calculations, and Word Problems with Fractions

    ERIC Educational Resources Information Center

    Fuchs, Lynn S.; Schumacher, Robin F.; Long, Jessica; Namkung, Jessica; Malone, Amelia S.; Wang, Amber; Hamlett, Carol L.; Jordan, Nancy C.; Siegler, Robert S.; Changas, Paul

    2016-01-01

    The purposes of this study were to (a) investigate the efficacy of a core fraction intervention program on understanding and calculation skill and (b) isolate the effects of different forms of fraction word-problem (WP) intervention. At-risk fourth graders (n = 213) were randomly assigned to the school's business-as-usual program, or one of two…

  10. The impossibility of probabilities

    NASA Astrophysics Data System (ADS)

    Zimmerman, Peter D.

    2017-11-01

    This paper discusses the problem of assigning probabilities to the likelihood of nuclear terrorism events, in particular examining the limitations of using Bayesian priors for this purpose. It suggests an alternate approach to analyzing the threat of nuclear terrorism.

  11. Condemnation : who should sit in judgment?.

    DOT National Transportation Integrated Search

    1975-01-01

    This report was written primarily for the legislator or researcher assigned to investigate alternative condemnation procedures. It attempted to draw together in one volume enough information to give the reader an appreciation of the problems that can...

  12. Federal Aviation Administration's Runway Incursion Program

    DOT National Transportation Integrated Search

    1997-12-08

    To reverse the upward trend in runway incursions, FAA must have a strong : Runway Incursion Program to solve systemwide problems and expedite : solutions. The Office of Inspector General report recommends that FAA (1) assign specific responsibility f...

  13. Dispersed processing for ATC.

    DOT National Transportation Integrated Search

    1971-06-01

    An analysis has been made of the potentialities and problems involved in assigning some computer processing and control functions to the remote sites in an upgraded third generation air traffic control system. Interrogator sites offer the most fruitf...

  14. Coercive Family Process and Early-Onset Conduct Problems From Age 2 to School Entry

    PubMed Central

    Smith, Justin D.; Dishion, Thomas J.; Shaw, Daniel S.; Wilson, Melvin N.; Winter, Charlotte C.; Patterson, Gerald R.

    2013-01-01

    The emergence and persistence of conduct problems during early childhood is a robust predictor of behavior problems in school and future maladaptation. In this study we examined the reciprocal influences between observed coercive interactions between children and caregivers, oppositional and aggressive behavior, and growth in parent report of early childhood (ages 2–5) and school-age conduct problems (age 7.5 and 8.5). Participants were drawn from the Early Steps multisite randomized prevention trial that includes an ethnically diverse sample of male and female children and their families (N = 731). A parallel process growth model combining latent trajectory and cross-lagged approaches revealed the amplifying effect of observed coercive caregiver–child interactions on children's noncompliance, whereas child oppositional and aggressive behaviors did not consistently predict increased coercion. The slope and initial levels of child oppositional and aggressive behaviors and the stability of caregiver–child coercion were predictive of teacher-reported oppositional behavior at school age. Families assigned to the Family Check-Up condition had significantly steeper declines in child oppositional and aggressive behavior and moderate reductions in oppositional behavior in school and in coercion at age 3. Results were not moderated by child gender, race/ethnicity, or assignment to the intervention condition. The implications of these findings are discussed with respect to understanding the early development of conduct problems and to designing optimal strategies for reducing problem behavior in early childhood with families most in need. PMID:24690305

  15. Improvement And Development Of The Motivation System In The Occupational And Industrial Safety Field

    NASA Astrophysics Data System (ADS)

    Pavlov, Arkhip; Gavrilov, Dmitrij

    2017-11-01

    This paper discusses one of the main problems in labour and industrial management in the occupational and industrial safety field - motivation to work safely. The problem is complex and should be solved by a set of measures, where the assignment of responsibility to employees for the results of their work is absent, including in the field of labour protection and industrial safety. In accordance with the obligatory management principles, employees' work resolves to the strict implementation of the actions prescribed by the regulations. The responsibility for the negative result rests with the person who enacted or instructs employees. Thus, the employee is practically exempt from responsibility for the final result. One of the possible solutions to this problem is to put an assignment of responsibility on the employees for the results of their activities also in the occupational and industrial safety field. This is illustrated by the experience of other states, particularly of Australia. In conclusion suggestions for improvement and development of the motivation system in the field of occupational and industrial safety.

  16. Sensor selection cost optimisation for tracking structurally cyclic systems: a P-order solution

    NASA Astrophysics Data System (ADS)

    Doostmohammadian, M.; Zarrabi, H.; Rabiee, H. R.

    2017-08-01

    Measurements and sensing implementations impose certain cost in sensor networks. The sensor selection cost optimisation is the problem of minimising the sensing cost of monitoring a physical (or cyber-physical) system. Consider a given set of sensors tracking states of a dynamical system for estimation purposes. For each sensor assume different costs to measure different (realisable) states. The idea is to assign sensors to measure states such that the global cost is minimised. The number and selection of sensor measurements need to ensure the observability to track the dynamic state of the system with bounded estimation error. The main question we address is how to select the state measurements to minimise the cost while satisfying the observability conditions. Relaxing the observability condition for structurally cyclic systems, the main contribution is to propose a graph theoretic approach to solve the problem in polynomial time. Note that polynomial time algorithms are suitable for large-scale systems as their running time is upper-bounded by a polynomial expression in the size of input for the algorithm. We frame the problem as a linear sum assignment with solution complexity of ?.

  17. Teaching an Old Dog an Old Trick: FREE-FIX and Free-Boundary Axisymmetric MHD Equilibrium

    NASA Astrophysics Data System (ADS)

    Guazzotto, Luca

    2015-11-01

    A common task in plasma physics research is the calculation of an axisymmetric equilibrium for tokamak modeling. The main unknown of the problem is the magnetic poloidal flux ψ. The easiest approach is to assign the shape of the plasma and only solve the equilibrium problem in the plasma / closed-field-lines region (the ``fixed-boundary approach''). Often, one may also need the vacuum fields, i.e. the equilibrium in the open-field-lines region, requiring either coil currents or ψ on some closed curve outside the plasma to be assigned (the ``free-boundary approach''). Going from one approach to the other is a textbook problem, involving the calculation of Green's functions and surface integrals in the plasma. However, no tools are readily available to perform this task. Here we present a code (FREE-FIX) to compute a boundary condition for a free-boundary equilibrium given only the corresponding fixed-boundary equilibrium. An improvement to the standard solution method, allowing for much faster calculations, is presented. Applications are discussed. PPPL fund 245139 and DOE grant G00009102.

  18. Multiple-step relayed correlation spectroscopy: sequential resonance assignments in oligosaccharides.

    PubMed Central

    Homans, S W; Dwek, R A; Fernandes, D L; Rademacher, T W

    1984-01-01

    A general property of the high-resolution proton NMR spectra of oligosaccharides is the appearance of low-field well-resolved resonances corresponding to the anomeric (H1) and H2 protons. The remaining skeletal protons resonate in the region 3-4 ppm, giving rise to an envelope of poorly resolved resonances. Assignments can be made from the H1 and H2 protons to their J-coupled neighbors (H2 and H3) within this main envelope by using 1H-1H correlated spectroscopy. However, the tight coupling (J congruent to delta) between further protons results in poor spectral dispersion with consequent assignment ambiguities. We describe here three-step two-dimensional relayed correlation spectroscopy and show how it can be used to correlate the resolved anomeric (H1) and H2 protons with remote (H4, H5) protons directly through a linear network of couplings using sequential magnetization transfer around the oligosaccharide rings. Resonance assignments are then obtained by inspection of cross-peaks that appear in well-resolved regions of the two-dimensional spectrum. This offers a general solution to the assignment problem in oligosaccharides and, importantly, these assignments will subsequently allow for the three-dimensional solution conformation to be determined by using one-dimensional and two-dimensional nuclear Overhauser experiments. PMID:6593701

  19. Safety in the Chemical Laboratory: An Undergraduate Chemical Laboratory Safety Course.

    ERIC Educational Resources Information Center

    Nicholls, L. Jewel

    1982-01-01

    Describes a two-quarter hour college chemistry course focusing on laboratory safety. Includes lists of topics/assignments, problem sets (toxicology, storage, and energy) and videotapes, films, and slide sets used in the course. (JN)

  20. DESIGNING PROCESSES FOR ENVIRONMENTAL PROBLEMS

    EPA Science Inventory

    Designing for the environment requires consideration of environmental impacts. The Generalized WAR Algorithm is the methodology that allows the user to evaluate the potential environmental impact of the design of a chemical process. In this methodology, chemicals are assigned val...

  1. Neural reactivations during sleep determine network credit assignment

    PubMed Central

    Gulati, Tanuj; Guo, Ling; Ramanathan, Dhakshin S.; Bodepudi, Anitha; Ganguly, Karunesh

    2018-01-01

    A fundamental goal of motor learning is to establish neural patterns that produce a desired behavioral outcome. It remains unclear how and when the nervous system solves this “credit–assignment” problem. Using neuroprosthetic learning where we could control the causal relationship between neurons and behavior, here we show that sleep–dependent processing is required for credit-assignment and the establishment of task-related functional connectivity reflecting the casual neuron-behavior relationship. Importantly, we found a strong link between the microstructure of sleep reactivations and credit assignment, with downscaling of non–causal activity. Strikingly, decoupling of spiking to slow–oscillations using optogenetic methods eliminated rescaling. Thus, our results suggest that coordinated firing during sleep plays an essential role in establishing sparse activation patterns that reflect the causal neuron–behavior relationship. PMID:28692062

  2. A primary shift rotation nurse scheduling using zero-one linear goal programming.

    PubMed

    Huarng, F

    1999-01-01

    In this study, the author discusses the effect of nurse shift schedules on circadian rhythm and some important ergonomics criteria. The author also reviews and compares different nurse shift scheduling methods via the criteria of flexibility, fairness, continuity in shift assignments, nurses' preferences, and ergonomics principles. In this article, a primary shift rotation system is proposed to provide better continuity in shift assignments to satisfy nurses' preferences. The primary shift rotation system is modeled as a zero-one linear goal programming (LGP) problem. To generate the shift assignment for a unit with 13 nurses, the zero-one LGP model takes less than 3 minutes on average, whereas the head nurses spend approximately 2 to 3 hours on shift scheduling. This study reports the process of implementing the primary shift rotation system.

  3. The petroleum explorationist's guide to contracts used in oil and gas operations

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

    Mosburg, L.G. Jr.

    This volume provides articles and current sample forms of contract negotiation and drafting. The contents include: An introduction to oil and gas contracts; Effective deal negotiation; General principles of contract law and negotiation; Problems and pitfalls in support agreements; Sample support agreements; Basic concept of farmout agreements; Farmout negotiation checklist; ''Area of mutual interest'' provisions, Problems and pitfalls in 'contract (minimum) depth' and 'farmout (earned) depth' provisions; Options in interests assigned and reserved; Sample 'AMI' provision; ''conventional'' and ''revenue ruling 77-176'' farmout agreement forms; the AAPL model from operating agreement; 1982 revisions to the model form; Side-by-side comparisons of themore » 1956, 1977 and 1982 model forms, 1984 (1985) COPAS accounting procedure; Tax consequences of oil and gas exploration and development, revenue ruling 77-176; Use of tax partnerships and present assignments; Also materials on gas balancing agreements: Seismic options; and Structuring considerations.« less

  4. Energy-Efficient Routing and Spectrum Assignment Algorithm with Physical-Layer Impairments Constraint in Flexible Optical Networks

    NASA Astrophysics Data System (ADS)

    Zhao, Jijun; Zhang, Nawa; Ren, Danping; Hu, Jinhua

    2017-12-01

    The recently proposed flexible optical network can provide more efficient accommodation of multiple data rates than the current wavelength-routed optical networks. Meanwhile, the energy efficiency has also been a hot topic because of the serious energy consumption problem. In this paper, the energy efficiency problem of flexible optical networks with physical-layer impairments constraint is studied. We propose a combined impairment-aware and energy-efficient routing and spectrum assignment (RSA) algorithm based on the link availability, in which the impact of power consumption minimization on signal quality is considered. By applying the proposed algorithm, the connection requests are established on a subset of network topology, reducing the number of transitions from sleep to active state. The simulation results demonstrate that our proposed algorithm can improve the energy efficiency and spectrum resources utilization with the acceptable blocking probability and average delay.

  5. Relabeling exchange method (REM) for learning in neural networks

    NASA Astrophysics Data System (ADS)

    Wu, Wen; Mammone, Richard J.

    1994-02-01

    The supervised training of neural networks require the use of output labels which are usually arbitrarily assigned. In this paper it is shown that there is a significant difference in the rms error of learning when `optimal' label assignment schemes are used. We have investigated two efficient random search algorithms to solve the relabeling problem: the simulated annealing and the genetic algorithm. However, we found them to be computationally expensive. Therefore we shall introduce a new heuristic algorithm called the Relabeling Exchange Method (REM) which is computationally more attractive and produces optimal performance. REM has been used to organize the optimal structure for multi-layered perceptrons and neural tree networks. The method is a general one and can be implemented as a modification to standard training algorithms. The motivation of the new relabeling strategy is based on the present interpretation of dyslexia as an encoding problem.

  6. Frequency-Weighting Filter Selection, for H2 Control of Microgravity Isolation Systems: A Consideration of the "Implicit Frequency Weighting" Problem

    NASA Technical Reports Server (NTRS)

    Hampton, Roy David; Whorton, Mark S.

    1999-01-01

    Many space-science experiments need an active isolation system to provide them with the requisite microgravity environment. The isolation systems planned for use with the International Space Station (ISS) have been appropriately modeled using relative position, relative velocity, and acceleration states. In theory, frequency-weighting design filters can be applied to these state-space models, in order to develop optimal H2 or mixed-norm controllers with desired stability and performance characteristics. In practice, however, since there is a kinematic relationship among the various states, any frequency weighting applied to one state will implicitly weight other states. These implicit frequency-weighting effects must be considered, for intelligent frequency-weighting filter assignment. This paper suggests a rational approach to the assignment of frequency-weighting design filters, in the presence of the kinematic coupling among states that exists in the microgravity vibration isolation problem.

  7. Neural-network dedicated processor for solving competitive assignment problems

    NASA Technical Reports Server (NTRS)

    Eberhardt, Silvio P. (Inventor)

    1993-01-01

    A neural-network processor for solving first-order competitive assignment problems consists of a matrix of N x M processing units, each of which corresponds to the pairing of a first number of elements of (R sub i) with a second number of elements (C sub j), wherein limits of the first number are programmed in row control superneurons, and limits of the second number are programmed in column superneurons as MIN and MAX values. The cost (weight) W sub ij of the pairings is programmed separately into each PU. For each row and column of PU's, a dedicated constraint superneuron insures that the number of active neurons within the associated row or column fall within a specified range. Annealing is provided by gradually increasing the PU gain for each row and column or increasing positive feedback to each PU, the latter being effective to increase hysteresis of each PU or by combining both of these techniques.

  8. Cramster: Friend or Foe?

    NASA Astrophysics Data System (ADS)

    Grams, Michael

    2011-04-01

    Recently when teaching a first-semester calculus-based physics course for engineers, I was perplexed by a particular group of students. These individuals were able to solve nearly every homework problem assigned from the end-of-chapter exercises in our textbook, and in some cases were able to do so using methods that we had not covered in class. However, they were unable to explain the steps in their solutions and when given similar problems on exams they performed very poorly. I became suspicious that these students were submitting homework solutions that were not their own, and a quick Internet search confirmed my fears. These students had been plagiarizing their homework assignments from a website called Cramster (www.cramster.com). In this article I would like to discuss the website, what some of my previous students and fellow educators think about it, and also consider whether or not Cramster could be useful in helping students learn physics.

  9. Network reliability maximization for stochastic-flow network subject to correlated failures using genetic algorithm and tabu\\xA0search

    NASA Astrophysics Data System (ADS)

    Yeh, Cheng-Ta; Lin, Yi-Kuei; Yang, Jo-Yun

    2018-07-01

    Network reliability is an important performance index for many real-life systems, such as electric power systems, computer systems and transportation systems. These systems can be modelled as stochastic-flow networks (SFNs) composed of arcs and nodes. Most system supervisors respect the network reliability maximization by finding the optimal multi-state resource assignment, which is one resource to each arc. However, a disaster may cause correlated failures for the assigned resources, affecting the network reliability. This article focuses on determining the optimal resource assignment with maximal network reliability for SFNs. To solve the problem, this study proposes a hybrid algorithm integrating the genetic algorithm and tabu search to determine the optimal assignment, called the hybrid GA-TS algorithm (HGTA), and integrates minimal paths, recursive sum of disjoint products and the correlated binomial distribution to calculate network reliability. Several practical numerical experiments are adopted to demonstrate that HGTA has better computational quality than several popular soft computing algorithms.

  10. The value of physical examination in mental health nursing.

    PubMed

    Martin, Carolyn T

    2016-03-01

    This article explores the use of a physical examination assignment in a mental health general nursing clinical placement course that addresses the poor physical health of people with mental illness and the barriers traditionally impeding health care provision for this population. A descriptive qualitative approach utilizes inductive content analysis to investigate 145 student survey responses. The assignment assists student nurses in understanding that physical and mental well-being are intrinsically linked. Students report increased comfort performing a physical examination on patients with mental illness post assignment. Students' initial bias towards this population was minimized post the clinical assignment. Poor physical health is common among people with mental health problems. Many view the provision of care as a major public health issue. Nurses are the front line caregivers of mental health service consumers and are well positioned to assess their physical needs. Their assessment may be the first step in recognizing health care issues in this population. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. The Effects of Schema-Broadening Instruction on Second Graders’ Word-Problem Performance and Their Ability to Represent Word Problems with Algebraic Equations: A Randomized Control Study

    PubMed Central

    Fuchs, Lynn S.; Zumeta, Rebecca O.; Schumacher, Robin Finelli; Powell, Sarah R.; Seethaler, Pamela M.; Hamlett, Carol L.; Fuchs, Douglas

    2010-01-01

    The purpose of this study was to assess the effects of schema-broadening instruction (SBI) on second graders’ word-problem-solving skills and their ability to represent the structure of word problems using algebraic equations. Teachers (n = 18) were randomly assigned to conventional word-problem instruction or SBI word-problem instruction, which taught students to represent the structural, defining features of word problems with overarching equations. Intervention lasted 16 weeks. We pretested and posttested 270 students on measures of word-problem skill; analyses that accounted for the nested structure of the data indicated superior word-problem learning for SBI students. Descriptive analyses of students’ word-problem work indicated that SBI helped students represent the structure of word problems with algebraic equations, suggesting that SBI promoted this aspect of students’ emerging algebraic reasoning. PMID:20539822

  12. Exploring Students' Mapping Behaviors and Interactive Discourses in a Case Diagnosis Problem: Sequential Analysis of Collaborative Causal Map Drawing Processes

    ERIC Educational Resources Information Center

    Lee, Woon Jee

    2012-01-01

    The purpose of this study was to explore the nature of students' mapping and discourse behaviors while constructing causal maps to articulate their understanding of a complex, ill-structured problem. In this study, six graduate-level students were assigned to one of three pair groups, and each pair used the causal mapping software program,…

  13. Structuring and Judgment in Decision Technology.

    DTIC Science & Technology

    1981-01-01

    partly because it avoids weighting questions in which only remotely related attributes need to be compared. But there are several potential problems...weighting questions in which only remotely related attributes need to be compared. But there are also problems; * C- for example, respondents may add to an...favoring the nuclear option assigned weights which were similar to those preferring coal. All groups gave the highest weight to the health/safety

  14. A mixed analog/digital chaotic neuro-computer system for quadratic assignment problems.

    PubMed

    Horio, Yoshihiko; Ikeguchi, Tohru; Aihara, Kazuyuki

    2005-01-01

    We construct a mixed analog/digital chaotic neuro-computer prototype system for quadratic assignment problems (QAPs). The QAP is one of the difficult NP-hard problems, and includes several real-world applications. Chaotic neural networks have been used to solve combinatorial optimization problems through chaotic search dynamics, which efficiently searches optimal or near optimal solutions. However, preliminary experiments have shown that, although it obtained good feasible solutions, the Hopfield-type chaotic neuro-computer hardware system could not obtain the optimal solution of the QAP. Therefore, in the present study, we improve the system performance by adopting a solution construction method, which constructs a feasible solution using the analog internal state values of the chaotic neurons at each iteration. In order to include the construction method into our hardware, we install a multi-channel analog-to-digital conversion system to observe the internal states of the chaotic neurons. We show experimentally that a great improvement in the system performance over the original Hopfield-type chaotic neuro-computer is obtained. That is, we obtain the optimal solution for the size-10 QAP in less than 1000 iterations. In addition, we propose a guideline for parameter tuning of the chaotic neuro-computer system according to the observation of the internal states of several chaotic neurons in the network.

  15. Statistical mechanics of budget-constrained auctions

    NASA Astrophysics Data System (ADS)

    Altarelli, F.; Braunstein, A.; Realpe-Gomez, J.; Zecchina, R.

    2009-07-01

    Finding the optimal assignment in budget-constrained auctions is a combinatorial optimization problem with many important applications, a notable example being in the sale of advertisement space by search engines (in this context the problem is often referred to as the off-line AdWords problem). On the basis of the cavity method of statistical mechanics, we introduce a message-passing algorithm that is capable of solving efficiently random instances of the problem extracted from a natural distribution, and we derive from its properties the phase diagram of the problem. As the control parameter (average value of the budgets) is varied, we find two phase transitions delimiting a region in which long-range correlations arise.

  16. Context-Aware Reviewer Assignment for Trust Enhanced Peer Review

    PubMed Central

    Li, Lei; Wang, Yan; Liu, Guanfeng; Wang, Meng; Wu, Xindong

    2015-01-01

    Reviewer assignment is critical to peer review systems, such as peer-reviewed research conferences or peer-reviewed funding applications, and its effectiveness is a deep concern of all academics. However, there are some problems in existing peer review systems during reviewer assignment. For example, some of the reviewers are much more stringent than others, leading to an unfair final decision, i.e., some submissions (i.e., papers or applications) with better quality are rejected. In this paper, we propose a context-aware reviewer assignment for trust enhanced peer review. More specifically, in our approach, we first consider the research area specific expertise of reviewers, and the institution relevance and co-authorship between reviewers and authors, so that reviewers with the right expertise are assigned to the corresponding submissions without potential conflict of interest. In addition, we propose a novel cross-assignment paradigm, and reviewers are cross-assigned in order to avoid assigning a group of stringent reviewers or a group of lenient reviewers to the same submission. More importantly, on top of them, we propose an academic CONtext-aware expertise relevanCe oriEnted Reviewer cross-assignmenT approach (CONCERT), which aims to effectively estimate the “true” ratings of submissions based on the ratings from all reviewers, even though no prior knowledge exists about the distribution of stringent reviewers and lenient reviewers. The experiments illustrate that compared with existing approaches, our proposed CONCERT approach can less likely assign more than one stringent reviewers or lenient reviewers to a submission simultaneously and significantly reduce the influence of ratings from stringent reviewers and lenient reviewers, leading to trust enhanced peer review and selection, no matter what kind of distributions of stringent reviewers and lenient reviewers are. PMID:26090849

  17. Thomas-Fermi model for a bulk self-gravitating stellar object in two dimensions

    NASA Astrophysics Data System (ADS)

    De, Sanchari; Chakrabarty, Somenath

    2015-09-01

    In this article we have solved a hypothetical problem related to the stability and gross properties of two-dimensional self-gravitating stellar objects using the Thomas-Fermi model. The formalism presented here is an extension of the standard three-dimensional problem discussed in the book on statistical physics, Part I by Landau and Lifshitz. Further, the formalism presented in this article may be considered a class problem for post-graduate-level students of physics or may be assigned as a part of their dissertation project.

  18. Optimal reconfiguration strategy for a degradable multimodule computing system

    NASA Technical Reports Server (NTRS)

    Lee, Yann-Hang; Shin, Kang G.

    1987-01-01

    The present quantitative approach to the problem of reconfiguring a degradable multimode system assigns some modules to computation and arranges others for reliability. By using expected total reward as the optimal criterion, there emerges an active reconfiguration strategy based not only on the occurrence of failure but the progression of the given mission. This reconfiguration strategy requires specification of the times at which the system should undergo reconfiguration, and the configurations to which the system should change. The optimal reconfiguration problem is converted to integer nonlinear knapsack and fractional programming problems.

  19. Antiferroelectric films of deuterated betaine phosphate

    NASA Astrophysics Data System (ADS)

    Balashova, E. V.; Krichevtsov, B. B.; Svinarev, F. B.; Zaitseva, N. V.

    2016-07-01

    Thin films of partially deuterated betaine phosphate have been grown by the evaporation on Al2O3(110) and NdGaO3(001) substrates with a preliminarily deposited structure of interdigitated electrodes. The grown films have a polycrystalline block structure with characteristic dimensions of blocks of the order of 0.1-1.5 mm. The degree of deuteration of the films D varies in the range of 20-50%. It has been found that, at the antiferroelectric phase transition temperature T c afe = 100-114 K, the fabricated structures exhibit an anomaly of the electrical capacitance C, which is not accompanied by a change in the dielectric loss tangent tanδ. The strong-signal dielectric response is characterized by the appearance of a ferroelectric nonlinearity at temperatures T > T c afe , which is transformed into an antiferroelectric nonlinearity at T < T c afe . With a further decrease in the temperature, double dielectric hysteresis loops appear in the antiferroelectric phase. The dielectric properties of the films have been described within the framework of the Landau-type thermodynamic model taking into account the biquadratic coupling ξ P 2η2 between the polar order parameter P and the nonpolar order parameter η with a positive coefficient ξ. The E-T phase diagram has been constructed.

  20. Lubrication of nonconformal contacts. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Jeng, Y. R.

    1985-01-01

    Minimum film thickness results for piezoviscous-rigid regime of lubrication are developed for a compressible Newtonian fluid with Roelands viscosity. The results provide a basis for the analysis and design of a wide range of machine elements operating in the piezoviscous-rigid regime of lubrication. A new numerical method of calculating elastic deformation in contact stresses is developed using a biquadratic polynomial to approximate the pressure distribution on the whole domain analyzed. The deformation of every node is expressed as a linear combination of the nodal pressures whose coefficients can be combined into an influence coefficient matrix. This approach has the advantages of improved numerical accuracy, less computing time and smaller storage size required for influence matrix. The ideal elastohydrodynamic lubrication is extended to real bearing systems in order to gain an understanding of failure mechanisms in machine elements. The improved elastic deformation calculation is successfully incorporated into the EHL numerical scheme. Using this revised numerical technique and the flow factor model developed by Patir and Cheng (1978) the surface roughness effects on the elastohydrodynamic lubrication of point contact is considered. Conditions typical of an EHL contact in the piezoviscous-elastic regime entrained in pure rolling are investigated. Results are compared with the smooth surface solutions. Experiments are conducted to study the transient EHL effects in instrument ball bearings.

  1. A downscaling scheme for atmospheric variables to drive soil-vegetation-atmosphere transfer models

    NASA Astrophysics Data System (ADS)

    Schomburg, A.; Venema, V.; Lindau, R.; Ament, F.; Simmer, C.

    2010-09-01

    For driving soil-vegetation-transfer models or hydrological models, high-resolution atmospheric forcing data is needed. For most applications the resolution of atmospheric model output is too coarse. To avoid biases due to the non-linear processes, a downscaling system should predict the unresolved variability of the atmospheric forcing. For this purpose we derived a disaggregation system consisting of three steps: (1) a bi-quadratic spline-interpolation of the low-resolution data, (2) a so-called `deterministic' part, based on statistical rules between high-resolution surface variables and the desired atmospheric near-surface variables and (3) an autoregressive noise-generation step. The disaggregation system has been developed and tested based on high-resolution model output (400m horizontal grid spacing). A novel automatic search-algorithm has been developed for deriving the deterministic downscaling rules of step 2. When applied to the atmospheric variables of the lowest layer of the atmospheric COSMO-model, the disaggregation is able to adequately reconstruct the reference fields. Applying downscaling step 1 and 2, root mean square errors are decreased. Step 3 finally leads to a close match of the subgrid variability and temporal autocorrelation with the reference fields. The scheme can be applied to the output of atmospheric models, both for stand-alone offline simulations, and a fully coupled model system.

  2. Viscous-resistive layer in Rayleigh-Taylor instability

    NASA Astrophysics Data System (ADS)

    Silveira, F. E. M.; Orlandi, H. I.

    2017-03-01

    In this work, new scaling laws of the time growth rate γ of the Rayleigh-Taylor instability with the plasma resistivity η, kinematic viscosity ν, and electron number density ne are derived. A viscosity scale is defined in terms of the time decay of the perturbative fluid flow perpendicular to the equilibrium magnetic field, at the quasi-static approximation. Such a scale provides the identification of a viscous layer that can be combined with the resistive layer to produce a viscous-resistive layer. The latter, in turn, is found to satisfy an algebraic biquadratic equation. When viscous effects are negligible, it is shown that the viscous-resistive layer is given by the resistive layer. Somewhat surprisingly, when viscous effects cannot be neglected, it is shown that the viscous-resistive layer is given by the geometric mean of the resistive and viscous layers. A dispersion relation for the time growth rate is derived in terms of the viscous-resistive layer. When viscous effects cannot be neglected, two new scaling laws are found. At the quasi-static approximation, it is shown that γ ˜ (ην)1/4. However, on account of a finite electron mass, it is shown that γ˜(ν/ne ) 1 /3 . Further developments of our formulation are addressed in connection with a finite compressibility in the perturbative flow.

  3. Strain and order-parameter coupling in Ni-Mn-Ga Heusler alloys from resonant ultrasound spectroscopy

    NASA Astrophysics Data System (ADS)

    Salazar Mejía, C.; Born, N.-O.; Schiemer, J. A.; Felser, C.; Carpenter, M. A.; Nicklas, M.

    2018-03-01

    Resonant ultrasound spectroscopy and magnetic susceptibility experiments have been used to characterize strain coupling phenomena associated with structural and magnetic properties of the shape-memory Heusler alloy series Ni50 +xMn25 -xGa25 (x =0 , 2.5, 5.0, and 7.5). All samples exhibit a martensitic transformation at temperature TM and ferromagnetic ordering at temperature TC, while the pure end member (x =0 ) also has a premartensitic transition at TP M, giving four different scenarios: TC>TP M>TM,TC>TM without premartensitic transition, TC≈TM , and TC

  4. Interpersonal problem-solving skills training in the treatment of self-poisoning patients.

    PubMed

    McLeavey, B C; Daly, R J; Ludgate, J W; Murray, C M

    1994-01-01

    The present study evaluated the effectiveness of interpersonal problem-solving skills training (IPSST) for the treatment of self-poisoning patients. Thirty-nine self-poisoning patients were assigned randomly either to IPSST or to a control treatment condition (a brief problem-oriented approach). Both conditions were equally effective in reducing the number of presenting problems and in reducing hopelessness levels. However, the IPSST condition was significantly more effective than the control condition as determined by other outcome measures (measures of interpersonal cognitive problem solving, self-rated personal problem-solving ability, perceived ability to cope with ongoing problems, and self-perception). Follow-up studies showed maintenance of IPSST treatment gains at 6 months and a greater reduction of repetition of self-poisoning in the IPSST group at 1 year posttreatment.

  5. A multiple-drawer medication layout problem in automated dispensing cabinets.

    PubMed

    Pazour, Jennifer A; Meller, Russell D

    2012-12-01

    In this paper we investigate the problem of locating medications in automated dispensing cabinets (ADCs) to minimize human selection errors. We formulate the multiple-drawer medication layout problem and show that the problem can be formulated as a quadratic assignment problem. As a way to evaluate various medication layouts, we develop a similarity rating for medication pairs. To solve industry-sized problem instances, we develop a heuristic approach. We use hospital ADC transaction data to conduct a computational experiment to test the performance of our developed heuristics, to demonstrate how our approach can aid in ADC design trade-offs, and to illustrate the potential improvements that can be made when applying an analytical process to the multiple-drawer medication layout problem. Finally, we present conclusions and future research directions.

  6. Taboo search algorithm for item assignment in synchronized zone automated order picking system

    NASA Astrophysics Data System (ADS)

    Wu, Yingying; Wu, Yaohua

    2014-07-01

    The idle time which is part of the order fulfillment time is decided by the number of items in the zone; therefore the item assignment method affects the picking efficiency. Whereas previous studies only focus on the balance of number of kinds of items between different zones but not the number of items and the idle time in each zone. In this paper, an idle factor is proposed to measure the idle time exactly. The idle factor is proven to obey the same vary trend with the idle time, so the object of this problem can be simplified from minimizing idle time to minimizing idle factor. Based on this, the model of item assignment problem in synchronized zone automated order picking system is built. The model is a form of relaxation of parallel machine scheduling problem which had been proven to be NP-complete. To solve the model, a taboo search algorithm is proposed. The main idea of the algorithm is minimizing the greatest idle factor of zones with the 2-exchange algorithm. Finally, the simulation which applies the data collected from a tobacco distribution center is conducted to evaluate the performance of the algorithm. The result verifies the model and shows the algorithm can do a steady work to reduce idle time and the idle time can be reduced by 45.63% on average. This research proposed an approach to measure the idle time in synchronized zone automated order picking system. The approach can improve the picking efficiency significantly and can be seen as theoretical basis when optimizing the synchronized automated order picking systems.

  7. E-health to improve work functioning in employees with rheumatoid arthritis in rheumatology practice: a feasibility study.

    PubMed

    Hoving, J L; Zoer, I; van der Meer, M; van der Straaten, Y; Logtenberg-Rutten, C; Kraak-Put, S; de Vries, N; Tak, P P; Sluiter, J K; Frings-Dresen, M H W

    2014-01-01

    To evaluate the feasibility of an e-health intervention in rheumatology practice for employees with rheumatoid arthritis (RA) who experience problems with work functioning. Twenty-three out of 90 patients with RA from a hospital rheumatology department, invited by letter, participated in a feasibility study. The 3-month internet e-health programme consisted of a self-management programme using a three-step problem-solving strategy: (step 1) analyse your work problems and opportunities; (step 3) identify solutions; and (step 3) work out a strategy (action plan). Support and personal feedback was provided by a rheumatology nurse. Patients completed assignments, received information, and actively worked on their goals. The main feasibility outcome included satisfaction with the programme. Other feasibility outcomes included usefulness, suitability, website use, and work functioning measured at baseline and/or 3 months using questionnaires, semi-structured interviews, and website data. In total, 95% of the participants were satisfied with the programme, and 96% thought the programme was useful for working RA patients and would recommend the programme to other working RA patients (91%). On the website, all patients at least partially completed the assignments in step 1 and 12 patients completed at least one assignment in step 3. Patients judged the website as well arranged with clear tasks. Patients worked on a range of (individual) goals, resolving work challenges using different strategies and actions. The e-health intervention is a feasible intervention for rheumatology practice justifying further effectiveness evaluation while allowing for further improvements in the selection of RA patients and shaping the intervention.

  8. A SAT Based Effective Algorithm for the Directed Hamiltonian Cycle Problem

    NASA Astrophysics Data System (ADS)

    Jäger, Gerold; Zhang, Weixiong

    The Hamiltonian cycle problem (HCP) is an important combinatorial problem with applications in many areas. While thorough theoretical and experimental analyses have been made on the HCP in undirected graphs, little is known for the HCP in directed graphs (DHCP). The contribution of this work is an effective algorithm for the DHCP. Our algorithm explores and exploits the close relationship between the DHCP and the Assignment Problem (AP) and utilizes a technique based on Boolean satisfiability (SAT). By combining effective algorithms for the AP and SAT, our algorithm significantly outperforms previous exact DHCP algorithms including an algorithm based on the award-winning Concorde TSP algorithm.

  9. Linking ecosystem services, rehabilitation and river hydrogeomorphology

    EPA Science Inventory

    Assignment of values for natural ecological benefits and anthropocentric ecosystem services in riverine landscapes has been problematic, because a firm scientific basis linking these to the river's physical structure has been absent. We highlight some inherent problems in this pr...

  10. The generalized quadratic knapsack problem. A neuronal network approach.

    PubMed

    Talaván, Pedro M; Yáñez, Javier

    2006-05-01

    The solution of an optimization problem through the continuous Hopfield network (CHN) is based on some energy or Lyapunov function, which decreases as the system evolves until a local minimum value is attained. A new energy function is proposed in this paper so that any 0-1 linear constrains programming with quadratic objective function can be solved. This problem, denoted as the generalized quadratic knapsack problem (GQKP), includes as particular cases well-known problems such as the traveling salesman problem (TSP) and the quadratic assignment problem (QAP). This new energy function generalizes those proposed by other authors. Through this energy function, any GQKP can be solved with an appropriate parameter setting procedure, which is detailed in this paper. As a particular case, and in order to test this generalized energy function, some computational experiments solving the traveling salesman problem are also included.

  11. Interdisciplinary Subject "Yakugaku Nyumon" for First-year Students Constructed with Lectures and Problem-based Learning.

    PubMed

    Yamaki, Kouya; Ueda, Masafumi; Ueda, Kumiko; Emoto, Noriaki; Mizutani, Nobuaki; Ikeda, Koji; Yagi, Keiko; Tanaka, Masafumi; Habu, Yasushi; Nakayama, Yoshiaki; Takeda, Norihiko; Moriwaki, Kensuke; Kitagawa, Shuji

    2016-01-01

    In 2013, Kobe Pharmaceutical University established "Yakugaku Nyumon", an interdisciplinary course, which consists of omnibus lectures and problem-based learning (PBL) on topics ranging from basic to clinical subjects. The themes of the PBL were original ones; "Study from package inserts of aspirin", which aimed to reinforce the contents of the interdisciplinary lectures, and "Let's think about aspirin derivatives (super-aspirin)", which aimed to engender an interest in studying pharmacy. The PBL featured questions from teachers to help with study and was therefore referred to as "question-led PBL" (Q-PBL). The Q-PBL regarding aspirin derivatives began with preparing answers to the questions for a small group discussion (SGD) as an assignment, followed by a SGD, a presentation, and peer-feedback. From an analysis of the questionnaire survey, it was found that students considered the Q-PBL satisfying and that they had achieved the 4 aims: (1) to increase the motivation to study, (2) to enhance an understanding of the relations and significance of basic and clinical sciences, (3) to comprehend the learning content, and (4) to recognize the importance of communication. The Q-PBL with assignments has two favorable points. One is that the first-year students can challenge difficult and high-level questions when they are given these as assignments. The other is that students, who are unfamiliar with SGD can engage in discussions with other students using the knowledge gained from the assignment. The introduction of omnibus lectures and Q-PBL, along with these improvements in theme, application, and review process, promises increased learning efficacy at the university.

  12. Use of genetic data to infer population-specific ecological and phenotypic traits from mixed aggregations

    USGS Publications Warehouse

    Moran, Paul; Bromaghin, Jeffrey F.; Masuda, Michele

    2014-01-01

    Many applications in ecological genetics involve sampling individuals from a mixture of multiple biological populations and subsequently associating those individuals with the populations from which they arose. Analytical methods that assign individuals to their putative population of origin have utility in both basic and applied research, providing information about population-specific life history and habitat use, ecotoxins, pathogen and parasite loads, and many other non-genetic ecological, or phenotypic traits. Although the question is initially directed at the origin of individuals, in most cases the ultimate desire is to investigate the distribution of some trait among populations. Current practice is to assign individuals to a population of origin and study properties of the trait among individuals within population strata as if they constituted independent samples. It seemed that approach might bias population-specific trait inference. In this study we made trait inferences directly through modeling, bypassing individual assignment. We extended a Bayesian model for population mixture analysis to incorporate parameters for the phenotypic trait and compared its performance to that of individual assignment with a minimum probability threshold for assignment. The Bayesian mixture model outperformed individual assignment under some trait inference conditions. However, by discarding individuals whose origins are most uncertain, the individual assignment method provided a less complex analytical technique whose performance may be adequate for some common trait inference problems. Our results provide specific guidance for method selection under various genetic relationships among populations with different trait distributions.

  13. Development and Application of ANN Model for Worker Assignment into Virtual Cells of Large Sized Configurations

    NASA Astrophysics Data System (ADS)

    Murali, R. V.; Puri, A. B.; Fathi, Khalid

    2010-10-01

    This paper presents an extended version of study already undertaken on development of an artificial neural networks (ANNs) model for assigning workforce into virtual cells under virtual cellular manufacturing systems (VCMS) environments. Previously, the same authors have introduced this concept and applied it to virtual cells of two-cell configuration and the results demonstrated that ANNs could be a worth applying tool for carrying out workforce assignments. In this attempt, three-cell configurations problems are considered for worker assignment task. Virtual cells are formed under dual resource constraint (DRC) context in which the number of available workers is less than the total number of machines available. Since worker assignment tasks are quite non-linear and highly dynamic in nature under varying inputs & conditions and, in parallel, ANNs have the ability to model complex relationships between inputs and outputs and find similar patterns effectively, an attempt was earlier made to employ ANNs into the above task. In this paper, the multilayered perceptron with feed forward (MLP-FF) neural network model has been reused for worker assignment tasks of three-cell configurations under DRC context and its performance at different time periods has been analyzed. The previously proposed worker assignment model has been reconfigured and cell formation solutions available for three-cell configuration in the literature are used in combination to generate datasets for training ANNs framework. Finally, results of the study have been presented and discussed.

  14. Use of Genetic Data to Infer Population-Specific Ecological and Phenotypic Traits from Mixed Aggregations

    PubMed Central

    Moran, Paul; Bromaghin, Jeffrey F.; Masuda, Michele

    2014-01-01

    Many applications in ecological genetics involve sampling individuals from a mixture of multiple biological populations and subsequently associating those individuals with the populations from which they arose. Analytical methods that assign individuals to their putative population of origin have utility in both basic and applied research, providing information about population-specific life history and habitat use, ecotoxins, pathogen and parasite loads, and many other non-genetic ecological, or phenotypic traits. Although the question is initially directed at the origin of individuals, in most cases the ultimate desire is to investigate the distribution of some trait among populations. Current practice is to assign individuals to a population of origin and study properties of the trait among individuals within population strata as if they constituted independent samples. It seemed that approach might bias population-specific trait inference. In this study we made trait inferences directly through modeling, bypassing individual assignment. We extended a Bayesian model for population mixture analysis to incorporate parameters for the phenotypic trait and compared its performance to that of individual assignment with a minimum probability threshold for assignment. The Bayesian mixture model outperformed individual assignment under some trait inference conditions. However, by discarding individuals whose origins are most uncertain, the individual assignment method provided a less complex analytical technique whose performance may be adequate for some common trait inference problems. Our results provide specific guidance for method selection under various genetic relationships among populations with different trait distributions. PMID:24905464

  15. UAVs Task and Motion Planning in the Presence of Obstacles and Prioritized Targets

    PubMed Central

    Gottlieb, Yoav; Shima, Tal

    2015-01-01

    The intertwined task assignment and motion planning problem of assigning a team of fixed-winged unmanned aerial vehicles to a set of prioritized targets in an environment with obstacles is addressed. It is assumed that the targets’ locations and initial priorities are determined using a network of unattended ground sensors used to detect potential threats at restricted zones. The targets are characterized by a time-varying level of importance, and timing constraints must be fulfilled before a vehicle is allowed to visit a specific target. It is assumed that the vehicles are carrying body-fixed sensors and, thus, are required to approach a designated target while flying straight and level. The fixed-winged aerial vehicles are modeled as Dubins vehicles, i.e., having a constant speed and a minimum turning radius constraint. The investigated integrated problem of task assignment and motion planning is posed in the form of a decision tree, and two search algorithms are proposed: an exhaustive algorithm that improves over run time and provides the minimum cost solution, encoded in the tree, and a greedy algorithm that provides a quick feasible solution. To satisfy the target’s visitation timing constraint, a path elongation motion planning algorithm amidst obstacles is provided. Using simulations, the performance of the algorithms is compared, evaluated and exemplified. PMID:26610522

  16. A new proposal for greenhouse gas emissions responsibility allocation: best available technologies approach.

    PubMed

    Berzosa, Álvaro; Barandica, Jesús M; Fernández-Sánchez, Gonzalo

    2014-01-01

    In recent years, several methodologies have been developed for the quantification of greenhouse gas (GHG) emissions. However, determining who is responsible for these emissions is also quite challenging. The most common approach is to assign emissions to the producer (based on the Kyoto Protocol), but proposals also exist for its allocation to the consumer (based on an ecological footprint perspective) and for a hybrid approach called shared responsibility. In this study, the existing proposals and standards regarding the allocation of GHG emissions responsibilities are analyzed, focusing on their main advantages and problems. A new model of shared responsibility that overcomes some of the existing problems is also proposed. This model is based on applying the best available technologies (BATs). This new approach allocates the responsibility between the producers and the final consumers based on the real capacity of each agent to reduce emissions. The proposed approach is demonstrated using a simple case study of a 4-step life cycle of ammonia nitrate (AN) fertilizer production. The proposed model has the characteristics that the standards and publications for assignment of GHG emissions responsibilities demand. This study presents a new way to assign responsibilities that pushes all the actors in the production chain, including consumers, to reduce pollution. © 2013 SETAC.

  17. Systematic Errors in Peptide and Protein Identification and Quantification by Modified Peptides*

    PubMed Central

    Bogdanow, Boris; Zauber, Henrik; Selbach, Matthias

    2016-01-01

    The principle of shotgun proteomics is to use peptide mass spectra in order to identify corresponding sequences in a protein database. The quality of peptide and protein identification and quantification critically depends on the sensitivity and specificity of this assignment process. Many peptides in proteomic samples carry biochemical modifications, and a large fraction of unassigned spectra arise from modified peptides. Spectra derived from modified peptides can erroneously be assigned to wrong amino acid sequences. However, the impact of this problem on proteomic data has not yet been investigated systematically. Here we use combinations of different database searches to show that modified peptides can be responsible for 20–50% of false positive identifications in deep proteomic data sets. These false positive hits are particularly problematic as they have significantly higher scores and higher intensities than other false positive matches. Furthermore, these wrong peptide assignments lead to hundreds of false protein identifications and systematic biases in protein quantification. We devise a “cleaned search” strategy to address this problem and show that this considerably improves the sensitivity and specificity of proteomic data. In summary, we show that modified peptides cause systematic errors in peptide and protein identification and quantification and should therefore be considered to further improve the quality of proteomic data annotation. PMID:27215553

  18. Discrimination of fish populations using parasites: Random Forests on a 'predictable' host-parasite system.

    PubMed

    Pérez-Del-Olmo, A; Montero, F E; Fernández, M; Barrett, J; Raga, J A; Kostadinova, A

    2010-10-01

    We address the effect of spatial scale and temporal variation on model generality when forming predictive models for fish assignment using a new data mining approach, Random Forests (RF), to variable biological markers (parasite community data). Models were implemented for a fish host-parasite system sampled along the Mediterranean and Atlantic coasts of Spain and were validated using independent datasets. We considered 2 basic classification problems in evaluating the importance of variations in parasite infracommunities for assignment of individual fish to their populations of origin: multiclass (2-5 population models, using 2 seasonal replicates from each of the populations) and 2-class task (using 4 seasonal replicates from 1 Atlantic and 1 Mediterranean population each). The main results are that (i) RF are well suited for multiclass population assignment using parasite communities in non-migratory fish; (ii) RF provide an efficient means for model cross-validation on the baseline data and this allows sample size limitations in parasite tag studies to be tackled effectively; (iii) the performance of RF is dependent on the complexity and spatial extent/configuration of the problem; and (iv) the development of predictive models is strongly influenced by seasonal change and this stresses the importance of both temporal replication and model validation in parasite tagging studies.

  19. Mini-Journals: Incorporating Inquiry, Quantitative Skills and Writing into Homework Assignments for Geochemistry and Planetary Science

    NASA Astrophysics Data System (ADS)

    Whittington, A. G.; Speck, A.; Witzig, S.

    2011-12-01

    As part of an NSF-funded project, "CUES: Connecting Undergraduates to the Enterprise of Science," new inquiry-based homework materials were developed for two upper-level classes at the University of Missouri: Geochemistry (required for Geology majors, fulfills the computing requirement by having 50% of the grade come from five spreadsheet-based homework assignments), and Solar System Science (open to seniors and graduate students, co-taught and cross-listed between Geology and Physics & Astronomy). Inquiry involves activities where the learner engages in scientifically oriented questions, gives priority to evidence in responding to questions, formulates explanations from evidence, connects explanations to scientific knowledge, and communicates and justifies explanations. We engage students in inquiry-based learning by presenting homework exercises as "mini-journal" articles that follow the format of a scientific journal article, including a title, authors, abstract, introduction, methods, results, discussion and citations to peer-reviewed literature. The mini-journal provides a scaffold and serves as a springboard for students to develop and carry out their own follow-up investigation. They then present their findings in the form of their own mini-journal. Mini-journals replace traditional homework problem sets with a format that more directly reflects and encourages scientific practice. Students are engaged in inquiry-based homework which encompass doing, thinking, and communicating, while the mini-journal allows the instructor to contain lines of inquiry within the limits posed by available resources. In the examples we present, research is conducted via spreadsheet modeling, where the students develop their own spreadsheets. Example assignments from Geochemistry include "Trace Element Partitioning During Mantle Melting and MORB Crystallization" and "Isotopic Investigations of Crustal Evolution in the Midcontinent US". The key differences between the old and new formats include (i) active participation of the students in defining the question/problem that they will pursue, within well-defined boundaries, (ii) open-ended nature of the inquiry, so that students need to recognize when they have enough information to answer their question, (iii) extensive spreadsheet manipulation and presentation of results in graphical and tabular formats, and (iv) a written discussion of their findings. Grading is weighted more towards how the problem was addressed, and how findings are presented and interpreted, and less on actual numerical answers. Survey responses from students indicate that they experience discomfort on being presented with an open-ended assignment, but like the freedom to define their own problem. Students also recognize that reading, writing and critical thinking skills employed in the minijournal format increase their understanding of content. The combination of calculation and writing components make these assignments particularly useful for classes designated as "computer-based", and/or "writing intensive" (or similar designations).

  20. Solving standard traveling salesman problem and multiple traveling salesman problem by using branch-and-bound

    NASA Astrophysics Data System (ADS)

    Saad, Shakila; Wan Jaafar, Wan Nurhadani; Jamil, Siti Jasmida

    2013-04-01

    The standard Traveling Salesman Problem (TSP) is the classical Traveling Salesman Problem (TSP) while Multiple Traveling Salesman Problem (MTSP) is an extension of TSP when more than one salesman is involved. The objective of MTSP is to find the least costly route that the traveling salesman problem can take if he wishes to visit exactly once each of a list of n cities and then return back to the home city. There are a few methods that can be used to solve MTSP. The objective of this research is to implement an exact method called Branch-and-Bound (B&B) algorithm. Briefly, the idea of B&B algorithm is to start with the associated Assignment Problem (AP). A branching strategy will be applied to the TSP and MTSP which is Breadth-first-Search (BFS). 11 nodes of cities are implemented for both problem and the solutions to the problem are presented.

  1. Production Scheduling of Sequenced Tapes for Printed Circuit Pack Assembly.

    DTIC Science & Technology

    1987-07-09

    detail. L j 6 The subject matter of this thesis is inspired directly from their technical report. The goals of this research are twofold: 1) Test their...The subject matter of the following chapters describes a heuristic approach to another variation of the sequenced tape production scheduling problem...assignment problem, comprise the subject matter of Chapter 5. It is sufficient to note that the three definitions of the term common correspond to the

  2. A United Framework for Solving Multiagent Task Assignment Problems

    DTIC Science & Technology

    2007-12-01

    Presented to the Faculty Graduate School of Engineering and Management Air Force Institute of Technology Air University Air Education and Training Command in...Member Date Date Accepted: 170-e<.. 01 DateM.V.THOMAS Dean, Graduate School of E,ngineering and Management Air Force Institute of Technology AFIT...actions in two different problem groups: using shame [37] for autonomous robots navigating a minefield, and a waiter - refiller service environment [94

  3. Rehabilitation R and D Progress Reports, 1991

    DTIC Science & Technology

    1991-01-01

    FES) is a challeng- work of our group , we are addressing the problem ing problem. A crucial difficulty is controlling the of designing a functional FES... control data. Background infor- research to design and evaluate interventions which mation will be obtained on the visual, sensory, help to reduce the...the senior was randomly Larger scale research is planned to investigate assigned to either a control or service group . the incidence of minor accidents

  4. A System Approach to Navy Medical Education and Training. Appendix 35. Competency Curriculum for Urology Assistant.

    DTIC Science & Technology

    1974-08-31

    urinary diversion b. Remove temporary/j ermanent collection appliance c. Perform basic sto-A care d. Cleanse /examine cc’Alection device prior to...of micturition d. Determine the type/degree/duration of urethral, vaginal , wound, other urinary outlet discharges e. Determine location/site and...related o. Determine if problem is vaginal /gynacologic p. Determine if problem is scrotal related PERFORMANCE OBJECTIVE (Stimulus) When assigned to

  5. Another Way to Divide a Line Segment into "n" Equal Parts

    ERIC Educational Resources Information Center

    Besteman, Nathan; Ferdinands, John

    2005-01-01

    Another way to divide a line segment discovered by Nathan Besteman is described along with Euclid's and the GLaD construction. The related projects and problems that teachers of geometry can assign to their students are also presented.

  6. Phase modulated 2D HSQC-TOCSY for unambiguous assignment of overlapping spin systems

    NASA Astrophysics Data System (ADS)

    Singh, Amrinder; Dubey, Abhinav; Adiga, Satish K.; Atreya, Hanudatta S.

    2018-01-01

    We present a new method that allows one to unambiguously resolve overlapping spin systems often encountered in biomolecular systems such as peptides and proteins or in samples containing a mixture of different molecules such as in metabolomics. We address this problem using the recently proposed phase modulation approach. By evolving the 1H chemical shifts in a conventional two dimensional (2D) HSQC-TOCSY experiment for a fixed delay period, the phase/intensity of set of cross peaks belonging to one spin system are modulated differentially relative to those of its overlapping counterpart, resulting in their discrimination and recognition. The method thus accelerates the process of identification and resonance assignment of individual compounds in complex mixtures. This approach facilitated the assignment of molecules in the embryo culture medium used in human assisted reproductive technology.

  7. Doctor-office collaborative care for pediatric behavioral problems: a preliminary clinical trial.

    PubMed

    Kolko, David J; Campo, John V; Kilbourne, Amy M; Kelleher, Kelly

    2012-03-01

    To evaluate the feasibility and clinical benefits of an integrated mental health intervention (doctor-office collaborative care [DOCC]) vs enhanced usual care (EUC) for children with behavioral problems. Cases were assigned to DOCC and EUC using a 2:1 randomization schedule that resulted in 55 DOCC and 23 EUC cases. Preassessment was conducted in 4 pediatric primary care practices. Postassessment was conducted in the pediatric or research office. Doctor-office collaborative care was provided in the practice; EUC was initiated in the office but involved a facilitated referral to a local mental health specialist. Of 125 referrals (age range, 5-12 years), 78 children participated. Children and their parents were assigned to receive DOCC or EUC. Preassessment diagnostic status was evaluated using the Schedule for Affective Disorders and Schizophrenia for School-aged Children. Preassessment and 6-month postassessment ratings of behavioral and emotional problems were collected from parents using the Vanderbilt Attention-Deficit/Hyperactivity Disorder Diagnostic Parent Rating Scale, as well as individualized goal achievement ratings forms. At discharge, care managers and a diagnostic evaluator completed the Clinical Global Impression Scale, and pediatricians and parents completed satisfaction and study feedback measures. Group comparisons found significant improvements for DOCC over EUC in service use and completion, behavioral and emotional problems, individualized behavioral goals, and overall clinical response. Pediatricians and parents were highly satisfied with DOCC. The feasibility and clinical benefits of DOCC for behavioral problems support the integration of collaborative mental health services for common mental disorders in primary care.

  8. Using In-class Group Exercises to Enhance Lectures and Provide Introductory Physics Students an Opportunity to Perfect Problem Solving Skills through Interactions with Fellow Students

    NASA Astrophysics Data System (ADS)

    Trout, Joseph; Bland, Jared

    2013-03-01

    In this pilot project, one hour of lecture time was replaced with one hour of in-class assignments, which groups of students collaborated on. These in-class assignments consisted of problems or projects selected for the calculus-based introductory physics students The first problem was at a level of difficulty that the majority of the students could complete with a small to moderate amount of difficulty. Each successive problem was increasingly more difficult, the last problem being having a level of difficulty that was beyond the capabilities of the majority of the students and required some instructor intervention. The students were free to choose their own groups. Students were encouraged to interact and help each other understand. The success of the in-class exercises were measured using pre-tests and post-tests. The pre-test and post-test were completed by each student independently. Statistics were also compiled on each student's attendance record and the amount of time spent reading and studying, as reported by the student. Statistics were also completed on the student responses when asked if they had sufficient time to complete the pre-test and post-test and if they would have completed the test with the correct answers if they had more time. The pre-tests and post-tests were not used in the computation of the grades of the students.

  9. Integrated assignment and path planning

    NASA Astrophysics Data System (ADS)

    Murphey, Robert A.

    2005-11-01

    A surge of interest in unmanned systems has exposed many new and challenging research problems across many fields of engineering and mathematics. These systems have the potential of transforming our society by replacing dangerous and dirty jobs with networks of moving machines. This vision is fundamentally separate from the modern view of robotics in that sophisticated behavior is realizable not by increasing individual vehicle complexity, but instead through collaborative teaming that relies on collective perception, abstraction, decision making, and manipulation. Obvious examples where collective robotics will make an impact include planetary exploration, space structure assembly, remote and undersea mining, hazardous material handling and clean-up, and search and rescue. Nonetheless, the phenomenon driving this technology trend is the increasing reliance of the US military on unmanned vehicles, specifically, aircraft. Only a few years ago, following years of resistance to the use of unmanned systems, the military and civilian leadership in the United States reversed itself and have recently demonstrated surprisingly broad acceptance of increasingly pervasive use of unmanned platforms in defense surveillance, and even attack. However, as rapidly as unmanned systems have gained acceptance, the defense research community has discovered the technical pitfalls that lie ahead, especially for operating collective groups of unmanned platforms. A great deal of talent and energy has been devoted to solving these technical problems, which tend to fall into two categories: resource allocation of vehicles to objectives, and path planning of vehicle trajectories. An extensive amount of research has been conducted in each direction, yet, surprisingly, very little work has considered the integrated problem of assignment and path planning. This dissertation presents a framework for studying integrated assignment and path planning and then moves on to suggest an exact mathematical model and solution techniques. The approach adopted is based upon the very flexible New Product Development model but also blends many features from other approaches. Solution methods using branch and bound and construction heuristics are developed and tested on several example problems, including a military scenario featuring unmanned air vehicles.

  10. Capacity planning of link restorable optical networks under dynamic change of traffic

    NASA Astrophysics Data System (ADS)

    Ho, Kwok Shing; Cheung, Kwok Wai

    2005-11-01

    Future backbone networks shall require full-survivability and support dynamic changes of traffic demands. The Generalized Survivable Networks (GSN) was proposed to meet these challenges. GSN is fully-survivable under dynamic traffic demand changes, so it offers a practical and guaranteed characterization framework for ASTN / ASON survivable network planning and bandwidth-on-demand resource allocation 4. The basic idea of GSN is to incorporate the non-blocking network concept into the survivable network models. In GSN, each network node must specify its I/O capacity bound which is taken as constraints for any allowable traffic demand matrix. In this paper, we consider the following generic GSN network design problem: Given the I/O bounds of each network node, find a routing scheme (and the corresponding rerouting scheme under failure) and the link capacity assignment (both working and spare) which minimize the cost, such that any traffic matrix consistent with the given I/O bounds can be feasibly routed and it is single-fault tolerant under the link restoration scheme. We first show how the initial, infeasible formal mixed integer programming formulation can be transformed into a more feasible problem using the duality transformation of the linear program. Then we show how the problem can be simplified using the Lagrangian Relaxation approach. Previous work has outlined a two-phase approach for solving this problem where the first phase optimizes the working capacity assignment and the second phase optimizes the spare capacity assignment. In this paper, we present a jointly optimized framework for dimensioning the survivable optical network with the GSN model. Experiment results show that the jointly optimized GSN can bring about on average of 3.8% cost savings when compared with the separate, two-phase approach. Finally, we perform a cost comparison and show that GSN can be deployed with a reasonable cost.

  11. Engineering calculations for communications systems planning

    NASA Technical Reports Server (NTRS)

    Levis, C. A.; Martin, C. H.; Wang, C. W.; Gonsalvez, D.

    1982-01-01

    The single entry interference problem is treated for frequency sharing between the broadcasting satellite and intersatellite services near 23 GHz. It is recommended that very long (more than 120 longitude difference) intersatellite hops be relegated to the unshared portion of the band. When this is done, it is found that suitable orbit assignments can be determined easily with the aid of a set of universal curves. An attempt to develop synthesis procedures for optimally assigning frequencies and orbital slots for the broadcasting satellite service in region 2 was initiated. Several discrete programming and continuous optimization techniques are discussed.

  12. PROMOTING SUPPORTIVE PARENTING IN NEW MOTHERS WITH SUBSTANCE-USE PROBLEMS: A PILOT RANDOMIZED TRIAL OF RESIDENTIAL TREATMENT PLUS AN ATTACHMENT-BASED PARENTING PROGRAM

    PubMed Central

    BERLIN, LISA J.; SHANAHAN, MEGHAN; CARMODY, KAREN APPLEYARD

    2015-01-01

    This pilot randomized trial tested the feasibility and efficacy of supplementing residential substance-abuse treatment for new mothers with a brief, yet rigorous, attachment-based parenting program. Twenty-one predominantly (86%) White mothers and their infants living together in residential substance-abuse treatment were randomly assigned to the program (n = 11) or control (n = 10) group. Program mothers received 10 home-based sessions of Dozier’s Attachment and Biobehavioral Catch-up (ABC) intervention. Postintervention observations revealed more supportive parenting behaviors among the randomly assigned ABC mothers. PMID:25424409

  13. Resonance assignment of the NMR spectra of disordered proteins using a multi-objective non-dominated sorting genetic algorithm.

    PubMed

    Yang, Yu; Fritzsching, Keith J; Hong, Mei

    2013-11-01

    A multi-objective genetic algorithm is introduced to predict the assignment of protein solid-state NMR (SSNMR) spectra with partial resonance overlap and missing peaks due to broad linewidths, molecular motion, and low sensitivity. This non-dominated sorting genetic algorithm II (NSGA-II) aims to identify all possible assignments that are consistent with the spectra and to compare the relative merit of these assignments. Our approach is modeled after the recently introduced Monte-Carlo simulated-annealing (MC/SA) protocol, with the key difference that NSGA-II simultaneously optimizes multiple assignment objectives instead of searching for possible assignments based on a single composite score. The multiple objectives include maximizing the number of consistently assigned peaks between multiple spectra ("good connections"), maximizing the number of used peaks, minimizing the number of inconsistently assigned peaks between spectra ("bad connections"), and minimizing the number of assigned peaks that have no matching peaks in the other spectra ("edges"). Using six SSNMR protein chemical shift datasets with varying levels of imperfection that was introduced by peak deletion, random chemical shift changes, and manual peak picking of spectra with moderately broad linewidths, we show that the NSGA-II algorithm produces a large number of valid and good assignments rapidly. For high-quality chemical shift peak lists, NSGA-II and MC/SA perform similarly well. However, when the peak lists contain many missing peaks that are uncorrelated between different spectra and have chemical shift deviations between spectra, the modified NSGA-II produces a larger number of valid solutions than MC/SA, and is more effective at distinguishing good from mediocre assignments by avoiding the hazard of suboptimal weighting factors for the various objectives. These two advantages, namely diversity and better evaluation, lead to a higher probability of predicting the correct assignment for a larger number of residues. On the other hand, when there are multiple equally good assignments that are significantly different from each other, the modified NSGA-II is less efficient than MC/SA in finding all the solutions. This problem is solved by a combined NSGA-II/MC algorithm, which appears to have the advantages of both NSGA-II and MC/SA. This combination algorithm is robust for the three most difficult chemical shift datasets examined here and is expected to give the highest-quality de novo assignment of challenging protein NMR spectra.

  14. The eyes have it: A Problem-Based Learning Exercise in Molecular Evolution.

    PubMed

    White, Harold B

    2007-05-01

    Molecular evolution provides an interesting context in which to use problem-based learning because it integrates a variety of topics in biology, biochemistry, and molecular biology. This three-stage problem for advanced students deals with the structure, multiple functions, and properties of lactate dehydrogenase isozymes, and the related evolutionary trade offs of gene sharing versus gene duplication among their corresponding genes. It has directive elements that require students to find and read classic articles, review thermodynamic principles, and apply their understanding to a mythical world wherein dinosaurs continued to evolve. The science fiction writing assignment that brings closure to the problem transformed the problem with respect to student interest and engagement. Copyright © 2007 International Union of Biochemistry and Molecular Biology, Inc.

  15. An Optimization Model for Scheduling Problems with Two-Dimensional Spatial Resource Constraint

    NASA Technical Reports Server (NTRS)

    Garcia, Christopher; Rabadi, Ghaith

    2010-01-01

    Traditional scheduling problems involve determining temporal assignments for a set of jobs in order to optimize some objective. Some scheduling problems also require the use of limited resources, which adds another dimension of complexity. In this paper we introduce a spatial resource-constrained scheduling problem that can arise in assembly, warehousing, cross-docking, inventory management, and other areas of logistics and supply chain management. This scheduling problem involves a twodimensional rectangular area as a limited resource. Each job, in addition to having temporal requirements, has a width and a height and utilizes a certain amount of space inside the area. We propose an optimization model for scheduling the jobs while respecting all temporal and spatial constraints.

  16. Can a Parenting Intervention to Prevent Early Conduct Problems Interrupt Girls' Risk for Intimate Partner Violence 10 Years Later?

    PubMed

    Ehrensaft, Miriam K; Westfall, Heather Knous; Niolon, Phyllis Holditch; Lopez, Thailyn; Kamboukos, Dimitra; Huang, Keng-Yen; Brotman, Laurie Miller

    2018-05-01

    This study tests whether a parenting intervention for families of preschoolers at risk for conduct problems can prevent later risk for intimate partner violence (IPV). Ninety-nine preschoolers at familial risk for conduct problems were randomly assigned to intervention or control conditions. Ten years later, 45 preschoolers and 43 of their siblings completed an assessment of their romantic relationships, including measures of physical and psychological IPV. The study focuses on the 54 females, including targets (n = 27) and siblings (n = 27) who participated in a 10-year follow-up (M age = 16.5, SD = 5.2, range = 10-28). Using an intent-to-treat (ITT) design, multivariate regressions suggest that females from families randomly assigned to intervention in early childhood scored lower than those in the control condition on perceptions of dating violence as normative, beliefs about IPV prevalence, exposure to IPV in their own peer group, and expected sanction behaviors for IPV perpetration and victimization. Findings suggest that early parenting intervention may reduce association of high-risk females with aggressive peers and partners in adolescence.

  17. Optimizing and accelerating the assignation of lineages in Mycobacterium tuberculosis using novel alternative single-tube assays

    PubMed Central

    Carcelén, María; Abascal, Estefanía; Herranz, Marta; Santantón, Sheila; Zenteno, Roberto; Ruiz Serrano, María Jesús; Bouza, Emilio

    2017-01-01

    The assignation of lineages in Mycobacterium tuberculosis (MTB) provides valuable information for evolutionary and phylogeographic studies and makes for more accurate knowledge of the distribution of this pathogen worldwide. Differences in virulence have also been found for certain lineages. MTB isolates were initially assigned to lineages based on data obtained from genotyping techniques, such as spoligotyping or MIRU-VNTR analysis, some of which are more suitable for molecular epidemiology studies. However, since these methods are subject to a certain degree of homoplasy, other criteria have been chosen to assign lineages. These are based on targeting robust and specific SNPs for each lineage. Here, we propose two newly designed multiplex targeting methods—both of which are single-tube tests—to optimize the assignation of the six main lineages in MTB. The first method is based on ASO-PCR and offers an inexpensive and easy-to-implement assay for laboratories with limited resources. The other, which is based on SNaPshot, enables more refined standardized assignation of lineages for laboratories with better resources. Both methods performed well when assigning lineages from cultured isolates from a control panel, a test panel, and a problem panel from an unrelated population, Mexico, which included isolates in which standard genotyping was not able to classify lineages. Both tests were also able to assign lineages from stored isolates, without the need for subculture or purification of DNA, and even directly from clinical specimens with a medium-high bacilli burden. Our assays could broaden the contexts where information on lineages can be acquired, thus enabling us to quickly update data from retrospective collections and to merge data with those obtained at the time of diagnosis of a new TB case. PMID:29091913

  18. Effects of AlcoholEdu for College on Alcohol-Related Problems Among Freshmen: A Randomized Multicampus Trial*

    PubMed Central

    Paschall, Mallie J.; Antin, Tamar; Ringwalt, Christopher L.; Saltz, Robert F.

    2011-01-01

    Objective: AlcoholEdu for College is a 2- to 3-hour online course for incoming college freshmen. This study was the first multicampus trial to examine effects of AlcoholEdu for College on alcohol-related problems among freshmen. Method: Thirty universi participated in the study. Fifteen were randomly assigned to receive AlcoholEdu, and the other 15 were assigned to the control condition. AlcoholEdu was implemented by intervention schools during the summer and/or fall semester. Cross-sectional surveys of freshmen were conducted at each university beginning before the intervention in spring 2008/2009; post-intervention surveys were administered in fall 2008/2009 and spring 2009/2010. The surveys included questions about the past-30-day frequency of 28 alcohol-related problems, from which we created indices for the total number of problems and problems in seven domains: physiological, academic, social, driving under the influence/riding with drinking drivers, aggression, sexual risk taking, and victimization. Multilevel Poisson regression analyses were conducted to examine intent-to-treat and dosage effects of AlcoholEdu for College on these outcomes. Results: Multilevel intent-to-treat analyses indicated significant reductions in the risk for past-30-day alcohol problems in general and problems in the physiological, social, and victimization domains during the fall semester immediately after completion of the course. However, these effects did not persist in the spring semester. Additional analyses suggested stronger AlcoholEdu effects on these outcomes at colleges with higher rates of student course completion. No AlcoholEdu effects were observed for alcohol-related problems in the other four domains. Conclusions: AlcoholEdu for College appears to have beneficial short-term effects on victimization and the most common types of alcohol-related problems among freshmen. Universities may benefit the most by mandating AlcoholEdu for College for all incoming freshmen and by implementing this online course along with environmental prevention strategies. PMID:21683046

  19. The uses of hopelessness.

    PubMed

    Bennett, M I; Bennett, M B

    1984-04-01

    If most emotional problems, like most medical problems, are caused by bad luck as well as by factors over which man has control, then those who suffer from such problems must accept a burden of helplessness. When patients and their families overuse theories of causality to avoid accepting their helplessness and to create an illusory sense of human control, unjust assignment of responsibility and excessive expectations for change may erode self-esteem and make change more difficult. The authors present examples of interventions that challenge the overuse of theories of causality. Although these interventions aroused hopelessness, they also fostered realistic hope and change.

  20. Program Helps To Determine Chemical-Reaction Mechanisms

    NASA Technical Reports Server (NTRS)

    Bittker, D. A.; Radhakrishnan, K.

    1995-01-01

    General Chemical Kinetics and Sensitivity Analysis (LSENS) computer code developed for use in solving complex, homogeneous, gas-phase, chemical-kinetics problems. Provides for efficient and accurate chemical-kinetics computations and provides for sensitivity analysis for variety of problems, including problems involving honisothermal conditions. Incorporates mathematical models for static system, steady one-dimensional inviscid flow, reaction behind incident shock wave (with boundary-layer correction), and perfectly stirred reactor. Computations of equilibrium properties performed for following assigned states: enthalpy and pressure, temperature and pressure, internal energy and volume, and temperature and volume. Written in FORTRAN 77 with exception of NAMELIST extensions used for input.

  1. 10 Steps for Implementing Change.

    ERIC Educational Resources Information Center

    Marsee, Jeff

    2002-01-01

    Offers steps for adapting the change process to institutional culture: align leadership style with organizational culture, don't overuse change missionaries, protect change agents, define the problem, maintain focus when the project drifts, identify and remove barriers before implementing action plans, assign responsibilities to individuals,…

  2. Rethinking the Research Paper in the Writing Center.

    ERIC Educational Resources Information Center

    McDonald, James C.

    1994-01-01

    Discusses the problems presented to writing center tutors by traditional research paper assignments. Recounts typical definitions of student research papers according to current-traditional rhetoric. Advocates writing centers helping students transform research papers into meaning-making activities in which students construct knowledge. (HB)

  3. The Idea Notebook.

    ERIC Educational Resources Information Center

    Journal of Experiential Education, 1981

    1981-01-01

    A new journal feature shares practical ideas in experiential education in less than 800 words. This issue presents an initiative problem, rules for rope push, exercise illustrating dependence on schedules, how to experience a handicap, maple sugaring project, assignment bridging the generation gap, simulating literary experiences, and local…

  4. University Learning Systems for Participative Courses.

    ERIC Educational Resources Information Center

    Billingham, Carol J.; Harper, William W.

    1980-01-01

    Describes the instructional development of a course for advanced finance students on the use of data files and/or databases for solving complex finance problems. Areas covered include course goals and the design. The course class schedule and sample learning assessment assignments are provided. (JD)

  5. Fundamental Studies of Strengthening Mechanisms in Metals Using Dislocation Dynamics

    DTIC Science & Technology

    2006-03-26

    to quantify the elastic fields of inclusion eigenstrain problems in 2D and 3D (Lerma et al. 2003). The inclusions can be of any shape or size and the... eigenstrains can be arbitrarily assigned, i.e. constant or non-constant within the inclusion. The method works well for material or field points...geometry and misfits. Recently, we have developed a new distributed-dislocation method for modeling eigenstrain problems such as gamma prime inclusions

  6. Secondary prevention of work-related disability in nonspecific low back pain: does problem-solving therapy help? A randomized clinical trial.

    PubMed

    van den Hout, Johanna H C; Vlaeyen, Johan W S; Heuts, Peter H T G; Zijlema, Johan H L; Wijnen, Joseph A G

    2003-01-01

    Given the individual and economic burden of chronic work disability in low back pain patients, there is a need for effective preventive interventions. The aim of the present study was to investigate whether problem-solving therapy had a supplemental value when added to behavioral graded activity, regarding days of sick leave and work status. Randomized controlled trial. Employees who were recently on sick leave as a result of nonspecific low back pain were referred to the rehabilitation center by general practitioner, occupational physician, or rehabilitation physician. Forty-five employees had been randomly assigned to the experimental treatment condition that included behavioral graded activity and problem-solving therapy (GAPS), and 39 employees had been randomly assigned to behavioral graded activity and group education (GAGE). Days of sick leave and work status. Data were retrieved from occupational health services. Data analyses showed that employees in the GAPS group had significantly fewer days of sick leave in the second half-year after the intervention. Moreover, work status was more favorable for employees in this condition, in that more employees had a 100% return-to-work and fewer patients ended up receiving disability pensions one year after the intervention. Sensitivity analyses confirmed these results. The addition of problem-solving therapy to behavioral graded activity had supplemental value in employees with nonspecific low back pain.

  7. Automated bond order assignment as an optimization problem.

    PubMed

    Dehof, Anna Katharina; Rurainski, Alexander; Bui, Quang Bao Anh; Böcker, Sebastian; Lenhof, Hans-Peter; Hildebrandt, Andreas

    2011-03-01

    Numerous applications in Computational Biology process molecular structures and hence strongly rely not only on correct atomic coordinates but also on correct bond order information. For proteins and nucleic acids, bond orders can be easily deduced but this does not hold for other types of molecules like ligands. For ligands, bond order information is not always provided in molecular databases and thus a variety of approaches tackling this problem have been developed. In this work, we extend an ansatz proposed by Wang et al. that assigns connectivity-based penalty scores and tries to heuristically approximate its optimum. In this work, we present three efficient and exact solvers for the problem replacing the heuristic approximation scheme of the original approach: an A*, an ILP and an fixed-parameter approach (FPT) approach. We implemented and evaluated the original implementation, our A*, ILP and FPT formulation on the MMFF94 validation suite and the KEGG Drug database. We show the benefit of computing exact solutions of the penalty minimization problem and the additional gain when computing all optimal (or even suboptimal) solutions. We close with a detailed comparison of our methods. The A* and ILP solution are integrated into the open-source C++ LGPL library BALL and the molecular visualization and modelling tool BALLView and can be downloaded from our homepage www.ball-project.org. The FPT implementation can be downloaded from http://bio.informatik.uni-jena.de/software/.

  8. Mutual benefit for foreign medical students and Chinese postgraduates: A mixed team-based learning method overcomes communication problems in hematology clerkship.

    PubMed

    Chen, Xianling; Chen, Buyuan; Li, Xiaofan; Song, Qingxiao; Chen, Yuanzhong

    2017-03-04

    Hematology is difficult for students to learn. A beneficial education method for hematology clerkship training is required to help students develop clinical skills. Foreign medical students often encounter communication issues in China. To address this issue, Chinese post-graduates from our institute are willing to assist with educating foreign students. Therefore, we propose a mixed team-based learning method (MTBL) which might overcome communication problems in hematology clerkship. Twenty-two foreign medical Students attended a 2-week hematology clerkship in Fujian Medical University Union Hospital. Twenty-one foreign African medical students were assigned randomly into two groups. Fourteen foreign African medical students were assigned to MTBL group. Each MTBL team included two foreign African medical students and one Chinese post-graduate. Seven foreign African medical students were assigned to lecture-based learning method (LBL) group, which had a foreign medical classmate from Hong Kong or Chinese intern volunteers to serve as translators. The practice test scores of MTBL were significantly higher than LBL group (p < 0.05). The MTBL group had increased motivation to prepare before class, an engaged classroom atmosphere, and an improvement in their understanding of difficult topics. Interestingly, the Chinese post-graduates also benefited from this setting, as they found that this interaction improved their communication in the English language. The mixed team-based learning method overcomes communication problems in hematology clerkship. Foreign medical students and Chinese post-graduates alike can benefit from MTBL. © 2016 by The International Union of Biochemistry and Molecular Biology, 45(2):93-96, 2017. © 2016 The International Union of Biochemistry and Molecular Biology.

  9. An initial approach towards quality of service based Spectrum Trading

    NASA Astrophysics Data System (ADS)

    Bastidas, Carlos E. Caicedo; Vanhoy, Garret; Volos, Haris I.; Bose, Tamal

    Spectrum scarcity has become an important issue as demands for higher data rates increase in diverse wireless applications and aerospace communication scenarios. To address this problem, it becomes necessary to manage radio spectrum assignment in a way that optimizes the distribution of spectrum resources among several users while taking into account the quality of service (QoS) characteristics desired by the users of spectrum. In this paper, a novel approach to managing spectrum assignment based on Spectrum Trading (ST) will be presented. Market based spectrum assignment mechanisms such as spectrum trading are of growing interest to many spectrum management agencies that are planning to increase the use of these mechanisms for spectrum management and reduce their emphasis on command and control methods. This paper presents some of our initial work into incorporating quality of service information into the mechanisms that determine how spectrum should be traded when using a spectrum exchange. Through simulations and a testbed implementation of a QoS aware spectrum exchange our results show the viability of using QoS based mechanisms in spectrum trading and in the enhancement of dynamic spectrum assignment systems.

  10. Performance evaluation of distributed wavelength assignment in WDM optical networks

    NASA Astrophysics Data System (ADS)

    Hashiguchi, Tomohiro; Wang, Xi; Morikawa, Hiroyuki; Aoyama, Tomonori

    2004-04-01

    In WDM wavelength routed networks, prior to a data transfer, a call setup procedure is required to reserve a wavelength path between the source-destination node pairs. A distributed approach to a connection setup can achieve a very high speed, while improving the reliability and reducing the implementation cost of the networks. However, along with many advantages, several major challenges have been posed by the distributed scheme in how the management and allocation of wavelength could be efficiently carried out. In this thesis, we apply a distributed wavelength assignment algorithm named priority based wavelength assignment (PWA) that was originally proposed for the use in burst switched optical networks to the problem of reserving wavelengths of path reservation protocols in the distributed control optical networks. Instead of assigning wavelengths randomly, this approach lets each node select the "safest" wavelengths based on the information of wavelength utilization history, thus unnecessary future contention is prevented. The simulation results presented in this paper show that the proposed protocol can enhance the performance of the system without introducing any apparent drawbacks.

  11. Constrained model predictive control, state estimation and coordination

    NASA Astrophysics Data System (ADS)

    Yan, Jun

    In this dissertation, we study the interaction between the control performance and the quality of the state estimation in a constrained Model Predictive Control (MPC) framework for systems with stochastic disturbances. This consists of three parts: (i) the development of a constrained MPC formulation that adapts to the quality of the state estimation via constraints; (ii) the application of such a control law in a multi-vehicle formation coordinated control problem in which each vehicle operates subject to a no-collision constraint posed by others' imperfect prediction computed from finite bit-rate, communicated data; (iii) the design of the predictors and the communication resource assignment problem that satisfy the performance requirement from Part (ii). Model Predictive Control (MPC) is of interest because it is one of the few control design methods which preserves standard design variables and yet handles constraints. MPC is normally posed as a full-state feedback control and is implemented in a certainty-equivalence fashion with best estimates of the states being used in place of the exact state. However, if the state constraints were handled in the same certainty-equivalence fashion, the resulting control law could drive the real state to violate the constraints frequently. Part (i) focuses on exploring the inclusion of state estimates into the constraints. It does this by applying constrained MPC to a system with stochastic disturbances. The stochastic nature of the problem requires re-posing the constraints in a probabilistic form. In Part (ii), we consider applying constrained MPC as a local control law in a coordinated control problem of a group of distributed autonomous systems. Interactions between the systems are captured via constraints. First, we inspect the application of constrained MPC to a completely deterministic case. Formation stability theorems are derived for the subsystems and conditions on the local constraint set are derived in order to guarantee local stability or convergence to a target state. If these conditions are met for all subsystems, then this stability is inherited by the overall system. For the case when each subsystem suffers from disturbances in the dynamics, own self-measurement noises, and quantization errors on neighbors' information due to the finite-bit-rate channels, the constrained MPC strategy developed in Part (i) is appropriate to apply. In Part (iii), we discuss the local predictor design and bandwidth assignment problem in a coordinated vehicle formation context. The MPC controller used in Part (ii) relates the formation control performance and the information quality in the way that large standoff implies conservative performance. We first develop an LMI (Linear Matrix Inequality) formulation for cross-estimator design in a simple two-vehicle scenario with non-standard information: one vehicle does not have access to the other's exact control value applied at each sampling time, but to its known, pre-computed, coupling linear feedback control law. Then a similar LMI problem is formulated for the bandwidth assignment problem that minimizes the total number of bits by adjusting the prediction gain matrices and the number of bits assigned to each variable. (Abstract shortened by UMI.)

  12. Phylogenetic Relationships within the Opisthokonta Based on Phylogenomic Analyses of Conserved Single-Copy Protein Domains

    PubMed Central

    Torruella, Guifré; Derelle, Romain; Paps, Jordi; Lang, B. Franz; Roger, Andrew J.; Shalchian-Tabrizi, Kamran; Ruiz-Trillo, Iñaki

    2012-01-01

    Many of the eukaryotic phylogenomic analyses published to date were based on alignments of hundreds to thousands of genes. Frequently, in such analyses, the most realistic evolutionary models currently available are often used to minimize the impact of systematic error. However, controversy remains over whether or not idiosyncratic gene family dynamics (i.e., gene duplications and losses) and incorrect orthology assignments are always appropriately taken into account. In this paper, we present an innovative strategy for overcoming orthology assignment problems. Rather than identifying and eliminating genes with paralogy problems, we have constructed a data set comprised exclusively of conserved single-copy protein domains that, unlike most of the commonly used phylogenomic data sets, should be less confounded by orthology miss-assignments. To evaluate the power of this approach, we performed maximum likelihood and Bayesian analyses to infer the evolutionary relationships within the opisthokonts (which includes Metazoa, Fungi, and related unicellular lineages). We used this approach to test 1) whether Filasterea and Ichthyosporea form a clade, 2) the interrelationships of early-branching metazoans, and 3) the relationships among early-branching fungi. We also assessed the impact of some methods that are known to minimize systematic error, including reducing the distance between the outgroup and ingroup taxa or using the CAT evolutionary model. Overall, our analyses support the Filozoa hypothesis in which Ichthyosporea are the first holozoan lineage to emerge followed by Filasterea, Choanoflagellata, and Metazoa. Blastocladiomycota appears as a lineage separate from Chytridiomycota, although this result is not strongly supported. These results represent independent tests of previous phylogenetic hypotheses, highlighting the importance of sophisticated approaches for orthology assignment in phylogenomic analyses. PMID:21771718

  13. Structuring Effective Student Teams.

    ERIC Educational Resources Information Center

    Dickson, Ellen L.

    1997-01-01

    Experience with student teams working on policy analysis projects indicates the need for faculty supervision of teams in the process of addressing complex issues. The problem-solving approach adopted in one policy analysis course is described, including assignments and tasks, issues and sponsors, team dynamics, conflict management, and the…

  14. Energy.

    ERIC Educational Resources Information Center

    Shanebrook, J. Richard

    This document describes a course designed to acquaint students with the many societal and technological problems facing the United States and the world due to the increasing demand for energy. The course begins with a writing assignment that involves readings on the environmental philosophy of Native Americans and the Chernobyl catastrophe.…

  15. Data Processing: Fifteen Suggestions for Computer Training in Your Business Education Classes.

    ERIC Educational Resources Information Center

    Barr, Lowell L.

    1980-01-01

    Presents 15 suggestions for training business education students in the use of computers. Suggestions involve computer language, method of presentation, laboratory time, programing assignments, instructions and handouts, problem solving, deadlines, reviews, programming concepts, programming logic, documentation, and defensive programming. (CT)

  16. National Airspace System : persistent problems in FAA's new navigation system highlight need for periodic reevaluation

    DOT National Transportation Integrated Search

    2000-06-01

    Currently, the Federal Aviation Administration (FAA) relies principally on a ground-based navigation system that uses various types of equipment to assist pilots in navigating their assigned routes and to provide them with guidance for landing their ...

  17. Executive Reentry: The Problems of Repatriation

    ERIC Educational Resources Information Center

    Cagney, William F.

    1975-01-01

    There are many ways in which a company can ease a foreign executive's transition from a foreign assignment to a United States headquarters job. Assistance in housing, accommodations, compensation, taxes, and home office atmosphere are just a few areas in which the company can help. (Author)

  18. Improving Language Acquisition through Journal Writing.

    ERIC Educational Resources Information Center

    Chanthalangsy, Sonevilay; Moskalis, Stan

    This study examined how journal writing could improve language minority students' language acquisition. Participants were Serbo-Croatian and Laotian second and third graders from two elementary schools. Initial student surveys and writing assignments, conducted in September to document the problem, found that students lacked writing skills,…

  19. A Review & Critique of Trainee-Oriented Training Programs.

    ERIC Educational Resources Information Center

    Klein-Konz, Ann; Todd-Mancillas, William R.

    This paper reviews literature on trainee-oriented training programs, which assign to individual employees predominant responsibility for diagnosing organizational problems requiring changes in employees' behaviors. A Self-Change, Adaption, and Modification (SCAM) Model is developed. The literature support for the model is written in similar…

  20. Developing learning community model with soft skill integration for the building engineering apprenticeship programme in vocational high school

    NASA Astrophysics Data System (ADS)

    Sutrisno, Dardiri, Ahmad; Sugandi, R. Machmud

    2017-09-01

    This study aimed to address the procedure, effectiveness, and problems in the implementation of learning model for Building Engineering Apprenticeship Training Programme. This study was carried out through survey method and experiment. The data were collected using questionnaire, test, and assessment sheet. The collected data were examined through description, t-test, and covariance analysis. The results of the study showed that (1) the model's procedure covered preparation course, readiness assessment, assignment distribution, handing over students to apprenticeship instructors, task completion, assisting, field assessment, report writing, and follow-up examination, (2) the Learning Community model could significantly improve students' active learning, but not improve students' hard skills and soft skills, and (3) the problems emerging in the implementation of the model were (1) students' difficulties in finding apprenticeship places and qualified instructors, and asking for relevant tasks, (2) teachers' difficulties in determining relevant tasks and monitoring students, and (3) apprenticeship instructors' difficulties in assigning, monitoring, and assessing students.

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