TY - RPRT
TI - On the differential equation dX dt = [X; k(X)] where k is a Toeplitz annihilator
AU - Chu, Moody
DA - 1993///
PY - 1993///
M3 - Preprint
ER -
TY - JOUR
TI - On a Multivariate Eigenvalue Problem, Part I: Algebraic Theory and a Power Method
AU - Chu, Moody T.
AU - Watterson, J. Loren
T2 - SIAM Journal on Scientific Computing
AB - Multivariate eigenvalue problems for symmetric and positive definite matrices arise from multivariate statistics theory where coefficients are to be determined so that the resulting linear combinations of sets of random variables are maximally correlated. By using the method of Lagrange multipliers such an optimization problem can be reduced to the multivariate eigenvalue problem. For over 30 years an iterative method proposed by Horst [Psychometrika, 26 (1961), pp. 129–149J has been used for solving the multivariate eigenvalue problem. Yet the theory of convergence has never been complete. The number of solutions to the multivariate eigenvalue problem also remains unknown. This paper contains two new results. By using the degree theory, a closed form on the cardinality of solutions for the multivariate eigenvalue problem is first proved. A convergence property of Horst’s method by forming it as a generalization of the so-called power method is then proved. The discussion leads to new formulations of numerical methods.
DA - 1993/9//
PY - 1993/9//
DO - 10.1137/0914066
VL - 14
IS - 5
SP - 1089-1106
UR - http://dx.doi.org/10.1137/0914066
ER -
TY - JOUR
TI - The stability group of symmetric Toeplitz matrices
AU - Chu, M.T.
T2 - Linear Algebra and Its Applications
AB - In regard to the linear subspace T(n) of n × n symmetric Toeplitz matrices over the real field, the collection L(n) of all real and orthogonal matrices Q such that QTQT ϵ L(n) whenever T ϵ T(n) forms a group, called the stability group of T(n). This paper shows that L(n) is finite. In fact, L(n) has exactly eight elements regardless of the dimension n. Group elements in L(n) are completely characterized.
DA - 1993///
PY - 1993///
DO - 10.1016/0024-3795(93)90208-6
VL - 185
IS - C
SP - 119-123
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-43949170372&partnerID=MN8TOARS
ER -
TY - CHAP
TI - Dynamic parallel evaluation of computation DAGs
AU - Kaltofen, E.
T2 - Synthesis of Parallel Algorithms
A2 - Reif, J.
PY - 1993///
SP - 723–758
PB - Morgan Kaufmann Publishers
ER -
TY - RPRT
TI - Computational differentiation and algebraic complexity theory
AU - Kaltofen, E.
A3 - Argonne National Laboratory
C6 - MCS-TM-183
DA - 1993/12//
PY - 1993/12//
SP - 28–30
M1 - ANL/MCS-TM-183
M3 - Technical Report
PB - Argonne National Laboratory
SN - ANL/MCS-TM-183
ER -
TY - CONF
TI - ADI methods for heat equations with discontinuities along an arbitrary interface
AU - Li, Zhilin
AU - Mayo, A
A2 - Gautschi, W.
C2 - 1993///
C3 - Proceedings of Symposia in Applied Mathematics
DA - 1993///
VL - 48
SP - 311–315
PB - AMS
ER -
TY - CONF
TI - Process scheduling in DSC and the large sparse linear systems challenge
AU - Diaz, A.
AU - Hitz, M.
AU - Kaltofen, E.
AU - Lobo, A.
AU - Valente, T.
T2 - Design and Implementation of Symbolic Computation Systems International Symposium, DISCO '93
T3 - Lecture Notes in Computer Science
C2 - 1993///
C3 - Design and Implementation of Symbolic Computation Systems (DISCO 1993)
CY - Gmunden, Austria
DA - 1993///
PY - 1993/9/15/
DO - 10.1007/bfb0013169
SP - 66–80
PB - Springer-Verlag
SN - 354057235X
UR - http://dx.doi.org/10.1007/bfb0013169
ER -
TY - JOUR
TI - Modeling of Flow Dynamics and its Impact on the Optimal Reactor Design Problem
AU - Tran, H.
AU - Scroggs, J.S.
AU - Bachmann, K.J.
T2 - Proceeding of 1992 AMS-IMS-SIAM Summer Research Conference on Control and Identification of Partial Differential Equations
DA - 1993///
PY - 1993///
SP - 1–13
ER -
TY - JOUR
TI - Heteroepitaxy of Wide Bandgap Ternary Semiconductors
AU - Bachmann, K. J.
AU - Xing, G. -C.
AU - Scroggs, J. S.
AU - Tran, H. T.
AU - Ito, K.
AU - Castleberry, H.
AU - Wood, G.
T2 - Japanese Journal of Applied Physics
DA - 1993/1/1/
PY - 1993/1/1/
DO - 10.7567/jjaps.32s3.133
VL - 32
IS - S3
SP - 133
J2 - Jpn. J. Appl. Phys.
OP -
SN - 0021-4922 1347-4065
UR - http://dx.doi.org/10.7567/jjaps.32s3.133
DB - Crossref
KW - HETEROEPITAXY
KW - I-III-VI(2)COMPOUNDS
KW - II-IV-V(2)COMPOUNDS
KW - MOCVD
KW - MBE
KW - LPE
KW - HALIDE TRANSPORT
ER -
TY - JOUR
TI - Estimation of Variable Cefficients in the Fokker–Planck Quations Using Moving Node Finite Elements
AU - Banks, H. T.
AU - Tran, H. T.
AU - Woodward, D. E.
T2 - SIAM Journal on Numerical Analysis
AB - Inverse problems are considered for the estimation of temporally and spatially varying coefficients in the Fokker–Planck or forward Kolmogorov equation that often arise in size/age structured population models. These are difficult problems even for simulation studies since they share certain numerical difficulties with transport-dominated diffusion-convection problems of fluid dynamics. These difficulties stem from the fact that when the convection is large compared to the diffusion, both traditional finite difference or finite element methods produce erroneous oscillatory solutions. In this paper, computational techniques are presented that combine a variation of the moving finite element method with spline approximations for the parameter estimation problems. Computational details of our numerical algorithm along with theoretical convergence results are presented. Several numerical examples illustrating the effectiveness of the method are also given.
DA - 1993/12//
PY - 1993/12//
DO - 10.1137/0730082
VL - 30
IS - 6
SP - 1574-1602
J2 - SIAM J. Numer. Anal.
LA - en
OP -
SN - 0036-1429 1095-7170
UR - http://dx.doi.org/10.1137/0730082
DB - Crossref
KW - FOKKER-PLANCK EQUATION
KW - PARAMETER IDENTIFICATION
KW - MOVING FINITE ELEMENTS
KW - CONVERGENCE THEORY
ER -
TY - CONF
TI - The Design of the SACLIB/PACLIB Kernels
AU - Hong, Hoon
AU - Neubacher, Andreas
AU - Schreiner, Wolfgang
A2 - Miola, Alfonso
C2 - 1993///
C3 - Design and Implementation of Symbolic Computation Systems, International
Symposium, DISCO '93, Gmunden, Austria, September 15-17, 1993, Proceedings
DA - 1993///
DO - 10.1007/BFb0013184
VL - 722
SP - 288-302
PB - Springer
UR - https://doi.org/10.1007/BFb0013184
ER -
TY - CONF
TI - The Design of the PACLIB Kernel for Parallel Algebraic Computation
AU - Schreiner, Wolfgang
AU - Hong, Hoon
A2 - Volkert, Jens
C2 - 1993///
C3 - Parallel Computation, Second International ACPC Conference, Gmunden,
Austria, October 4-6, 1993, Proceedings
DA - 1993///
DO - 10.1007/3-540-57314-3\_17
VL - 734
SP - 204-218
PB - Springer
UR - https://doi.org/10.1007/3-540-57314-3\_17
ER -
TY - CONF
TI - Parallelization of Quantifier Elimination on a Workstation Network
AU - Hong, Hoon
A2 - Cohen, Gérard D.
A2 - Mora, Teo
A2 - Moreno, Oscar
C2 - 1993///
C3 - Applied Algebra, Algebraic Algorithms and Error-Correcting Codes,
10th International Symposium, AAECC-10, San Juan de Puerto Rico, Puerto
Rico, May 10-14, 1993, Proceedings
DA - 1993///
DO - 10.1007/3-540-56686-4\_42
VL - 673
SP - 170-179
PB - Springer
UR - https://doi.org/10.1007/3-540-56686-4\_42
ER -
TY - JOUR
TI - Special Issue Editorial: Computational Quantifier Elimination
AU - Hong, Hoon
T2 - Comput. J.
DA - 1993///
PY - 1993///
DO - 10.1093/comjnl/36.5.399
VL - 36
IS - 5
SP - 399
UR - https://doi.org/10.1093/comjnl/36.5.399
ER -
TY - CHAP
TI - RISC-CLP (Real): Logic Programming with Non-Linear Constraints over the Reals
AU - Hong, Hoon
T2 - Constraint Logic Programming: Selected Research
PY - 1993///
SP - 133–159
PB - MIT Press
ER -
TY - CONF
TI - Quantifier elimination for formulas constrained by quadratic equations
AU - Hong, Hoon
A2 - Bronstein, Manuel
AB - Article Free Access Share on Quantifier elimination for formulas constrained by quadratic equations Author: Hoon Hong View Profile Authors Info & Claims ISSAC '93: Proceedings of the 1993 international symposium on Symbolic and algebraic computationAugust 1993 Pages 264–274https://doi.org/10.1145/164081.164140Online:01 August 1993Publication History 8citation266DownloadsMetricsTotal Citations8Total Downloads266Last 12 Months2Last 6 weeks0 Get Citation AlertsNew Citation Alert added!This alert has been successfully added and will be sent to:You will be notified whenever a record that you have chosen has been cited.To manage your alert preferences, click on the button below.Manage my AlertsNew Citation Alert!Please log in to your account Save to BinderSave to BinderCreate a New BinderNameCancelCreateExport CitationPublisher SiteeReaderPDF
C2 - 1993///
C3 - Proceedings of the 1993 international symposium on Symbolic and algebraic computation - ISSAC '93
DA - 1993///
DO - 10.1145/164081.164140
SP - 264-274
PB - ACM Press
UR - http://dx.doi.org/10.1145/164081.164140
ER -
TY - JOUR
TI - Quantifier Elimination for Formulas Constrained by Quadratic Equations via Slope Resultants
AU - Hong, H.
T2 - The Computer Journal
AB - An algorithm is given for eliminating the quantifier from a formula: (∃x ∈ R)[a2x2 + a1x + a0 = 0 ∧ F], where F is a quantifier free formula in x1,…,xr, x, and a2, a1, a0 are polynomials in x1, …, xr with real coefficients such that the system {a2=0, a1=0, a0=0} has no solution in R;r. The output formulas are made of resultants and their variants, which we call slope resultants. The slope resultants can be, like the resultants, expressed as determinants of certain matrices. If we allow the determinant symbol in the output, the computing time of the algorithm is linear in the length of the input. If not, the computing time is dominated by N(n2r+1l+n2rl2) where N is the number of polynomials in the input formula, r is the number of variables, n is the maximum of the degrees for every variable, and l is the maximum of the integer coefficient bit lengths. Experiments with implementation suggest that the algorithm is sufficiently efficient to be useful in practice.
DA - 1993/5/1/
PY - 1993/5/1/
DO - 10.1093/comjnl/36.5.439
VL - 36
IS - 5
SP - 439-449
UR - http://dx.doi.org/10.1093/comjnl/36.5.439
ER -
TY - CONF
TI - A New Library for Parallel Algebraic Computation
AU - Schreiner, Wolfgang
AU - Hong, Hoon
A2 - Sincovec, Richard F.
A2 - Keyes, David E.
A2 - Leuze, Michael R.
A2 - Petzold, Linda R.
A2 - Reed, Daniel A.
C2 - 1993///
C3 - Proceedings of the Sixth SIAM Conference on Parallel Processing
for Scientific Computing, PPSC 1993, Norfolk, Virginia, USA, March
22-24, 1993
DA - 1993///
SP - 776-783
PB - SIAM
ER -
TY - JOUR
TI - AN INEXPENSIVE INFRARED GROWTH SENSOR ARRAY FOR DETECTION OF BACTERIAL ANTIBIOTIC SUSCEPTIBILITY
T2 - FEMS Microbiology Letters
AB - An inexpensive infrared sensor was constructed and used for the rapid testing of bacterial antibiotic susceptibility by detection of changes in absorbance at 950 nm. By comparing cultures of clinical isolates together with control strains (Escherichia coli NCTC 10418, Staphylococcus aureus NCTC 6571 or Pseudomonas aeruginosa NCTC 10662) after addition of an antibiotic, results on susceptibility were obtained within 3–5 h from the original plate culture. Representative strains of E. coli, P. aeruginosa, and S. aureus were tested successfully against ampicillin, penicillin, gentamicin or ciprofloxacin.
DA - 1993///
PY - 1993///
DO - 10.1016/0378-1097(93)90389-J
UR - https://publons.com/publon/9840930/
ER -
TY - JOUR
TI - Unloading near a shear band: a free boundary problem for the wave equation
AU - Schaeffer, David G.
AU - Shearer, Michael
T2 - Communications in Partial Differential Equations
DA - 1993/1//
PY - 1993/1//
DO - 10.1080/03605309308820974
VL - 18
IS - 7-8
SP - 1271-1298
J2 - Communications in Partial Differential Equations
LA - en
OP -
SN - 0360-5302 1532-4133
UR - http://dx.doi.org/10.1080/03605309308820974
DB - Crossref
ER -
TY - JOUR
TI - The Initial Value Problem for a System Modelling Unidirectional Longitudinal Elastic-Plastic Waves
AU - Shearer, Michael
AU - Schaeffer, David G.
T2 - SIAM Journal on Mathematical Analysis
AB - The authors analyze initial value problems for a hyperbolic system of equations that is a simplification of models of dynamic longitudinal elastoplastic deformations in a rod with hardening. The simplified system has a positive characteristic speed associated with stress waves, and a zero speed associated with the time independence of hardening during elastic deformation. The equations are piecewise linear in stress derivatives, and thus fully nonlinear. The main result is that for bounded uniformly continuous initial data, the Cauchy problem has a unique continuous solution that can be approximated by piecewise linear solutions of the equations.
DA - 1993/9//
PY - 1993/9//
DO - 10.1137/0524065
VL - 24
IS - 5
SP - 1111-1144
J2 - SIAM J. Math. Anal.
LA - en
OP -
SN - 0036-1410 1095-7154
UR - http://dx.doi.org/10.1137/0524065
DB - Crossref
KW - ELASTOPLASTICITY
KW - HYPERBOLIC EQUATIONS
KW - FULLY NONLINEAR PARTIAL DIFFERENTIAL EQUATIONS
KW - INITIAL VALUE PROBLEM
KW - WEAK SOLUTIONS
ER -
TY - JOUR
TI - Nonstrictly Hyperbolic Conservation Laws with a Parabolic Line
AU - Schaeffer, D.G.
AU - Schecter, S.
AU - Shearer, M.
T2 - Journal of Differential Equations
DA - 1993/5//
PY - 1993/5//
DO - 10.1006/jdeq.1993.1043
VL - 103
IS - 1
SP - 94-126
J2 - Journal of Differential Equations
LA - en
OP -
SN - 0022-0396
UR - http://dx.doi.org/10.1006/jdeq.1993.1043
DB - Crossref
ER -
TY - CONF
TI - A simultaneous projection method for inconsistent signal and image feasibility problems
AU - Combettes, P.L.
T2 - Proceedings of the Eighth IEEE Workshop on Image and Multidimensional Signal Processing
C2 - 1993///
C3 - Proceedings of the Eighth IEEE Workshop on Image and Multidimensional Signal Processing
CY - Cannes, France
DA - 1993///
PY - 1993/9/8/
SP - 32–33
ER -
TY - CHAP
TI - Estimation en présence de modèles incertains: sélection de formulations ensemblistes
AU - Combettes, P.L.
AU - Chaussalet, T.J.
T2 - Actes du Quatorzième Colloque GRETSI
PY - 1993/9/13/
SP - 205–208
UR - http://hdl.handle.net/2042/12154
ER -
TY - CHAP
TI - Analysis of Coppersmith's block Wiedemann algorithm for the parallel solution of sparse linear systems
AU - Kaltofen, Erich
T2 - Applied Algebra, Algebraic Algorithms and Error-Correcting Codes
PY - 1993///
DO - 10.1007/3-540-56686-4_44
SP - 195-212
OP -
PB - Springer Berlin Heidelberg
SN - 9783540566861 9783540476306
UR - http://dx.doi.org/10.1007/3-540-56686-4_44
DB - Crossref
ER -
TY - JOUR
TI - Direct proof of a theorem by Kalkbrener, Sweedler, and Taylor
AU - Kaltofen, Erich
T2 - ACM SIGSAM Bulletin
AB - For given f 1 ,..., f m ∈ K [ x ] that are relatively prime, where K is a field, Kalkbrener, Sweedler, and Taylor (1993) present degree bounds on the a i needed to express 1 (and other low degree polynomials) as Σ a i f i . Their bounds are an improvement on bounds given by Kakié (1976). This note presents a direct proof of the following fact.
DA - 1993/12/1/
PY - 1993/12/1/
DO - 10.1145/182125.182126
VL - 27
IS - 4
SP - 2
J2 - SIGSAM Bull.
LA - en
OP -
SN - 0163-5824
UR - http://dx.doi.org/10.1145/182125.182126
DB - Crossref
ER -
TY - JOUR
TI - Hypothesis: the central oscillator of the circadian clock is a controlled chaotic attractor
AU - Lloyd, Alun L.
AU - Lloyd, David
T2 - Biosystems
AB - Controlled chaos may be important for the generation of rhythmic behaviour in living systems. A model is proposed in which the central circadian oscillator is a chaotic attractor. Whereas a limit cycle mechanism (previously invoked to explain circadian clocks as well as ultradian clocks and cell division cycles) can provide only a single stable periodic orbit, a chaotic attractor can generate rich dynamic behaviour. Control by feedback makes accessible a selected stabilized orbit; this can be chosen so as to optimize system performance. Such a system can accommodate a wide variety of requirements, e.g. that a single clock mutation can affect both period and temperature compensation, and the generation of higher periods from an ultradian oscillator. Simultaneous operation of more than one clock (with differing periods) may require a high-dimension chaotic attractor. Attractive features of such a model include versatility of period selection (e.g. as in the per mutants of Drosophila) and the use of control elements of the type already well known in metabolic circuitry.
DA - 1993///
PY - 1993///
DO - http://dx.doi.org/10.1016/0303-2647(93)90085-q
VL - 29
IS - 2-3
SP - 77–85
ER -
TY - CONF
TI - Volterra prediction models and higher order whiteness
AU - Bondon, P.
AU - Combettes, P.L.
AU - Picinbono, B.
T2 - 1993 IEEE International Conference on Acoustics, Speech, and Signal Processing
AB - For nonGaussian processes, a nonlinear predictor can achieve a smaller prediction error than a linear one. The authors study Volterra predictors and compare them with their linear counterparts. The concept of Volterra unpredictability leads to important generalizations of the notion of white noise to higher orders. These generalizations are introduced and relations are established between them. Examples are provided to show that the relations between these higher order whitenesses are not trivial.< >
C2 - 1993///
C3 - IEEE International Conference on Acoustics Speech and Signal Processing
CY - Minneapolis, Minnesota
DA - 1993///
PY - 1993/4/27/
DO - 10.1109/icassp.1993.319632
PB - IEEE
SN - 0780309464
UR - http://dx.doi.org/10.1109/icassp.1993.319632
ER -
TY - CONF
TI - Parallel projection methods for set theoretic signal reconstruction and restoration
AU - Combettes, P.L.
AU - Puh, H.
T2 - 1993 IEEE International Conference on Acoustics, Speech, and Signal Processing
AB - An attempt is made to lay a theoretical and computational foundation for the use of parallel projection methods in set-theoretic signal restoration and reconstruction. A general method of parallel projections (MOPP) for solving feasibility problems in Hilbert spaces is proposed. In the proposed scheme, an elementary iteration consists in projecting the current estimate simultaneously onto selected sets and forming a relaxed convex combination of the projections. MOPP is seen to have substantial advantages over the method of successive projections, the widely used serial projection method which it generalizes: straightforward implementation on a parallel computing architecture, an explicit condition on the relaxation coefficients for faster convergence, and convergence to weighted least-squares solutions for inconsistent set-theoretic formulations. Convergence results for this algorithm in the convex and nonconvex cases are presented. Both consistent and inconsistent set-theoretic formulations are considered. Practical issues pertaining to the utilization of the method are discussed.< >
C2 - 1993///
C3 - IEEE International Conference on Acoustics Speech and Signal Processing
CY - Minneapolis, Minnesota
DA - 1993///
PY - 1993/4/27/
DO - 10.1109/icassp.1993.319806
PB - IEEE
SN - 0780309464
UR - http://dx.doi.org/10.1109/icassp.1993.319806
ER -
TY - JOUR
TI - Artificial Boundary Conditions for the Numerical Solution of
External Viscous Flow Problems. II
T2 - Rossijskaya Akad. Nauk Inst. Prikl. Mat. Preprint
DA - 1993///
PY - 1993///
IS - 46
N1 - [in Russian]
RN - [in Russian]
ER -
TY - JOUR
TI - Artificial Boundary Conditions for the Numerical Solution of
External Viscous Flow Problems. I
T2 - Rossijskaya Akad. Nauk Inst. Prikl. Mat. Preprint
DA - 1993///
PY - 1993///
IS - 45
N1 - [in Russian]
RN - [in Russian]
ER -
TY - JOUR
TI - The foundations of set theoretic estimation
AU - Combettes, P.L.
T2 - Proceedings of the IEEE
AB - Explains set theoretic estimation, which is governed by the notion of feasibility and produces solutions whose sole property is to be consistent with all information arising from the observed data and a priori knowledge. Each piece of information is associated with a set in the solution space, and the intersection of these sets, the feasibility set, represents the acceptable solutions. The practical use of the set theoretic framework stems from the existence of efficient techniques for finding these solutions. Many scattered problems in systems science and signal processing have been approached in set theoretic terms over the past three decades. The author synthesizes a single, general framework from these various approaches, examines its fundamental philosophy, goals, and analytical techniques, and relates it to conventional methods.< >
DA - 1993/2//
PY - 1993/2//
DO - 10.1109/5.214546
VL - 81
IS - 2
SP - 182-208
J2 - Proc. IEEE
OP -
SN - 0018-9219
UR - http://dx.doi.org/10.1109/5.214546
DB - Crossref
ER -
TY - JOUR
TI - Signal recovery by best feasible approximation
AU - Combettes, P.L.
T2 - IEEE Transactions on Image Processing
AB - The objective of set theoretical signal recovery is to find a feasible signal in the form of a point in the intersection of S of sets modeling the information available about the problem. For problems in which the true signal is known to lie near a reference signal r, the solution should not be any feasible point but one which best approximates r, i.e., a projection of r onto S. Such a solution cannot be obtained by the feasibility algorithms currently in use, e.g., the method of projections onto convex sets (POCS) and its offsprings. Methods for projecting a point onto the intersection of closed and convex sets in a Hilbert space are introduced and applied to signal recovery by best feasible approximation of a reference signal. These algorithms are closely related to the above projection methods, to which they add little computational complexity.
DA - 1993/4//
PY - 1993/4//
DO - 10.1109/83.217232
VL - 2
IS - 2
SP - 269-271
J2 - IEEE Trans. on Image Process.
OP -
SN - 1057-7149
UR - http://dx.doi.org/10.1109/83.217232
DB - Crossref
ER -
TY - JOUR
TI - Asymptotically Exact Boundary Conditions for the {P-N} Equations
AU - Ganapol, B D
AU - Kelley, C T
AU - Pomraning, G C
T2 - Nuclear Science and Engineering
DA - 1993///
PY - 1993///
VL - 114
SP - 12-19
ER -
TY - CONF
TI - A Non-Quasi-Static Modular Model for {HBT}s
AU - Morris, A S
AU - Trew, R J
AU - Kelley, C T
AU - Hayes, G J
T2 - IEEE
C2 - 1993///
C3 - Proceedings IEEE/Cornell Conference on Advanced Concepts in High Speed Devices and Circuits
DA - 1993///
SP - 440-447
ER -
TY - JOUR
TI - Least squares completions for nonlinear differential algebraic equations
AU - Campbell, Stephen L.
T2 - Numerische Mathematik
DA - 1993/12//
PY - 1993/12//
DO - 10.1007/bf01385741
VL - 65
IS - 1
SP - 77-94
J2 - Numer. Math.
LA - en
OP -
SN - 0029-599X 0945-3245
UR - http://dx.doi.org/10.1007/bf01385741
DB - Crossref
ER -
TY - JOUR
TI - Hypothesis: the central oscillator of the circadian clock is a controlled chaotic attractor
AU - Lloyd, Alun L.
AU - Lloyd, David
T2 - Biosystems
AB - Controlled chaos may be important for the generation of rhythmic behaviour in living systems. A model is proposed in which the central circadian oscillator is a chaotic attractor. Whereas a limit cycle mechanism (previously invoked to explain circadian clocks as well as ultradian clocks and cell division cycles) can provide only a single stable periodic orbit, a chaotic attractor can generate rich dynamic behaviour. Control by feedback makes accessible a selected stabilized orbit; this can be chosen so as to optimize system performance. Such a system can accommodate a wide variety of requirements, e.g. that a single clock mutation can affect both period and temperature compensation, and the generation of higher periods from an ultradian oscillator. Simultaneous operation of more than one clock (with differing periods) may require a high-dimension chaotic attractor. Attractive features of such a model include versatility of period selection (e.g. as in the per mutants of Drosophila) and the use of control elements of the type already well known in metabolic circuitry.
DA - 1993/1//
PY - 1993/1//
DO - 10.1016/0303-2647(93)90085-q
VL - 29
IS - 2-3
SP - 77-85
J2 - Biosystems
LA - en
OP -
SN - 0303-2647
UR - http://dx.doi.org/10.1016/0303-2647(93)90085-q
DB - Crossref
KW - CHAOS
KW - CIRCADIAN CLOCK
KW - ULTRADIAN CLOCK
KW - CELL DIVISION CYCLE
KW - BIOLOGICAL CLOCKS
KW - BIOLOGICAL RHYTHMS
KW - PER MUTATION IN DROSOPHILA
KW - FRQ MUTATION IN NEUROSPORA
ER -
TY - JOUR
TI - An inexpensive infrared growth sensor array for detection of bacterial antibiotic susceptibility
AU - Mason, David J.
AU - Lloyd, Alun L.
AU - Lloyd, David
T2 - FEMS Microbiology Letters
AB - An inexpensive infrared sensor was constructed and used for the rapid testing of bacterial antibiotic susceptibility by detection of changes in absorbance at 950 nm. By comparing cultures of clinical isolates together with control strains (Escherichia coli NCTC 10418, Staphylococcus aureus NCTC 6571 or Pseudomonas aeruginosa NCTC 10662) after addition of an antibiotic, results on susceptibility were obtained within 3-5 h from the original plate culture. Representative strains of E. coli, P. aeruginosa, and S. aureus were tested successfully against ampicillin, penicillin, gentamicin or ciprofloxacin.
DA - 1993/8//
PY - 1993/8//
DO - 10.1111/j.1574-6968.1993.tb06394.x
VL - 111
IS - 2-3
SP - 251-254
LA - en
OP -
SN - 0378-1097 1574-6968
UR - http://dx.doi.org/10.1111/j.1574-6968.1993.tb06394.x
DB - Crossref
ER -
TY - CHAP
TI - Models for Control in Smart Material Structures
AU - Banks, H.T.
AU - Smith, R.C.
T2 - Identification and Control in Systems Governed by Partial Differential Equations
PY - 1993///
SP - 26–44
PB - SIAM
ER -
TY - JOUR
TI - Convergence analysis for the harmonic balance method
AU - Kelley, C.T.
AU - Mukundan, L.
T2 - Nonlinear Analysis: Theory, Methods & Applications
DA - 1993/2//
PY - 1993/2//
DO - 10.1016/0362-546x(93)90141-e
VL - 20
IS - 4
SP - 365-380
J2 - Nonlinear Analysis: Theory, Methods & Applications
LA - en
OP -
SN - 0362-546X
UR - http://dx.doi.org/10.1016/0362-546x(93)90141-e
DB - Crossref
KW - HARMONIC BALANCE METHOD
KW - KANTOROVICH THEOREM
KW - INTEGRAL EQUATIONS
KW - MULTILEVEL ALGORITHMS
ER -
TY - JOUR
TI - Pointwise Broyden Methods
AU - Kelley, C. T.
AU - Sachs, E. W.
T2 - SIAM Journal on Optimization
AB - Pointwise quasi-Newton methods are designed for nonlinear equations and optimization problems in function spaces. They update coefficients of differential and integral operators and therefore take advantage of finer structure than conventional quasi-Newton methods. In this paper a general theory for those pointwise quasi-Newton methods that are based on Broyden’s method are given. This paper unifies the theory of pointwise methods with that for Broyden's method in Hilbert space. A new superlinearly convergent method is introduced for elliptic boundary value problems and the new theory allows for a direct extension of a pointwise method for integral equations.
DA - 1993/5//
PY - 1993/5//
DO - 10.1137/0803020
VL - 3
IS - 2
SP - 423-441
J2 - SIAM J. Optim.
LA - en
OP -
SN - 1052-6234 1095-7189
UR - http://dx.doi.org/10.1137/0803020
DB - Crossref
KW - pointwise quasi-Newton method
KW - superlinear convergence
ER -
TY - JOUR
TI - Asymptotically Exact Boundary Conditions for the PN Equations
AU - Ganapol, B. D.
AU - Kelley, C. T.
AU - Pomraning, G. C.
T2 - Nuclear Science and Engineering
AB - It was recently demonstrated that in planar geometry, the classic PN equations are an asymptotic limit of the transport equation. A corresponding boundary layer analysis established the asymptotica...
DA - 1993/5//
PY - 1993/5//
DO - 10.13182/nse93-a24010
VL - 114
IS - 1
SP - 12-19
J2 - Nuclear Science and Engineering
LA - en
OP -
SN - 0029-5639 1943-748X
UR - http://dx.doi.org/10.13182/nse93-a24010
DB - Crossref
ER -
TY - JOUR
TI - A fast multi-level method for the fixed point form of matrix H-equations
AU - Kelley, C. T.
AU - Northrup, J. I.
T2 - Transport Theory and Statistical Physics
AB - Abstract In previous work of the authors quasi-Newton and multi-level algorithms for fully nonlinear integral equations were designed and analyzed. The motivating examples for that work were analogs of the Chandrasekhar H-equation for matrix-valued functions. A weakness of these algorithms was that transfer between grids was done with a piecewise linear interpolation instead of Nystrom interpolation. This choice of interpolation was used because the nonlinearity in the Chandrasekhar equation was expressed in the quadratic form for which a matrix inversion is not required. In this paper we reconsider the fixed point formulation and resolve a conditioning issue associated with the matrix. This allows us to use Nyström interpolation and obtain a more efficient multi-level method. We also discuss implementation details on the Alliant FX series of multiprocessor computers.
DA - 1993/8//
PY - 1993/8//
DO - 10.1080/00411459308203827
VL - 22
IS - 4
SP - 533-547
J2 - Transport Theory and Statistical Physics
LA - en
OP -
SN - 0041-1450 1532-2424
UR - http://dx.doi.org/10.1080/00411459308203827
DB - Crossref
ER -
TY - JOUR
TI - Inexact Newton Methods for singular problems
AU - Kelley, C. T.
AU - Xue, Z. Q.
T2 - Optimization Methods and Software
AB - In this paper we describe the effects of an inexact implementation of Newton's method on the behavior of the iteration for certain nonlinear equations in Banach space for which the Fréchet derivative is singular at the solution. We give a termination criterion for the inner iteration that preserves not only the q-linear convergence of the Newton iterates but also the fine structure required for an acceleration method.
DA - 1993/1//
PY - 1993/1//
DO - 10.1080/10556789308805545
VL - 2
IS - 3-4
SP - 249-267
J2 - Optimization Methods and Software
LA - en
OP -
SN - 1055-6788 1029-4937
UR - http://dx.doi.org/10.1080/10556789308805545
DB - Crossref
ER -
TY - JOUR
TI - Sinc-Galerkin estimation of diffusivity in parabolic problems
AU - Smith, R C
AU - Bowers, K L
T2 - Inverse Problems
AB - A fully Sinc-Galerkin method for the numerical recovery of spatially varying diffusion coefficients in linear parabolic partial differential equations is presented. Because the parameter recovery problems are inherently ill-posed, an output error criterion in conjunction with Tikhonov regularization is used to formulate them as infinite-dimensional minimization problems. The forward problems are discretized with a sinc basis in both the spatial and temporal domains thus yielding an approximate solution which displays an exponential convergence rate and is valid on the infinite time interval. The minimization problems are then solved via a quasi-Newton/trust region algorithm. The L-curve technique for determining an appropriate value of the regularization parameter is briefly discussed, and numerical examples are given which demonstrate the applicability of the method both for problems with noise-free data as well as for those whose data contain white noise.
DA - 1993/2/1/
PY - 1993/2/1/
DO - 10.1088/0266-5611/9/1/007
VL - 9
IS - 1
SP - 113-135
J2 - Inverse Problems
OP -
SN - 0266-5611 1361-6420
UR - http://dx.doi.org/10.1088/0266-5611/9/1/007
DB - Crossref
ER -
TY - JOUR
TI - Approximation Methods for Control of Structural Acoustics Models with Piezoceramic Actuators
AU - Banks, H.T.
AU - Fang, W.
AU - Silcox, R.J.
AU - Smith, R.C.
T2 - Journal of Intelligent Material Systems and Structures
AB - The active control of acoustic pressure in a 2-D cavity with a flexible boundary (a beam) is considered. Specifically, this control is implemented via piezoceramic patches on the beam which produce pure bending moments. The incorporation of the feedback control in this manner leads to a system with an unbounded input term. Approximation methods in the context of an LQR state space formulation are discussed and numerical results demonstrating the effectiveness of this approach in computing feedback controls for noise reduction are presented.
DA - 1993/1//
PY - 1993/1//
DO - 10.1177/1045389x9300400113
VL - 4
IS - 1
SP - 98-116
J2 - Journal of Intelligent Material Systems and Structures
LA - en
OP -
SN - 1045-389X 1530-8138
UR - http://dx.doi.org/10.1177/1045389x9300400113
DB - Crossref
ER -
TY - JOUR
TI - 'Mountain Gold' tomato
AU - Gardner, R. G.
T2 - HortScience
DA - 1993///
PY - 1993///
VL - 28
IS - 4
SP - 348
ER -
TY - JOUR
TI - 'Mountain Belle' cherry tomato; NC 1C and NC 2C cherry tomato breeding lines
AU - Gardner, R. G.
T2 - HortScience
DA - 1993///
PY - 1993///
VL - 28
IS - 4
SP - 349
ER -