Simultaneous Assignment Research Articles

In situ hybridization banding of human chromosomes with Alu-PCR products: A simultaneous karyotype for gene mapping studies

Polymerase chain reaction products generated from a single Alu primer and human genomic DNA produce a distinct and highly reproducible R-banding pattern when hybridized to metaphase chromosome spreads. Individual chromosomes can be readily identified and karyotyped. Compared to conventional fluorescence banding on heat-denatured chromosomes, the in situ hybridization banding (ISHB) shows high contrast and definition. We demonstrate that this banding method can be employed effectively in double-labeling experiments for the rapid and simultaneous assignment of probes to specific chromosomal bands. Since virtually any fluorochrome can be used to delineate chromosomal bands, ISHB should provide added flexibility for multicolor mapping strategies.

Eigenstructure assignment in a longitudinal power system via excitation control

A study is made of the control method for the simultaneous assignment of eigenvalues and eigenvectors, which is often referred to as eigenstructure assignment. The motivation for eigenstructure assignment is that system damping can be improved by means of eigenvalue assignment and that the system dynamic behavior can be altered using eigenvector assignment. The proposed control scheme is of the decentralized output feedback supplementary excitation control configuration which is most desirable in practice. Results obtained from the application of the proposed controller to the system studied, which is of longitudinal structure, show that exact assignment of the eigenstructure associated with the worst-damped electromechanical mode can be achieved. The effect of eigenvector assignment on the participation factor is also investigated.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Simultaneous pole assignment in linear periodic systems by constrained structure feedback

The authors present methods for pole assignment by feedback with constrained structure in linear periodic systems using generalized sampled-data hold functions (GSHF). Constrained structure is taken to mean that the input of each channel is restricted to depend only on the measurements of some specific output channels. The basic idea of GSHF control is to use sample and hold, but to consider the hold function as a design parameter. Four strategies are proposed for closing a control loop using GSHF. The key to the results obtained is that, when GSHF control with constrained structure is applied to a periodic system, a discrete-time time-invariant, decentralized system is obtained for which control design methods are available. >

Pole assignment in rotating disk vibration control using complex modal state feedback

Modal state feedback controls of rotating disk vibrations in real and complex fields are formulated and compared. Pole assignment in real modal space necessitates the simultaneous assignment of eigenvalues and eigenvectors to uniquely determine the feedback gain matrix. Pole assignment in complex modal space, however, uniquely determines the feedback gain matrix, because preservation of the isotropic nature in the uncontrolled and controlled modal systems only allows the assignment of the isotropic eigenstructure. The proposed complex modal control scheme reduces the order of the system to be dealt with. It also minimises the required control energy and the transient magnitudes of the state.

Revised assignments of the 13C NMR spectrum of hibalactone using 2D heteronuclear 1H/13C correlations

AbstractOne‐bond and long‐range two‐dimensional 1H/13C NMR experiments allow the unequivocal and simultaneous assignment of 13C and 1H spectra. On this basis, previous assignments of 13C signals of hibalactone have been revised.

A systematic method for eigenstructure assignment and application to response shaping

The simultaneous assignment of eigenvalue and eigenvector in a dynamic system using a constant-gain state-feedback controller is formulated as a static optimization problem. Response shaping by adequately damping the dominant modes or by eliminating the uncontrollable modes is possible in this formulation. Systematic solution through a standard LP routine makes the method attractive for practical implementation. The proposed eigenstructure-assignment algorithm is illustrated through two examples, one of which is the stabilization of a single machine connected to an infinite-bus power system.

Human apolipoprotein A-I and C-III genes reside in the p11 → q13 region of chromosome 11

Apolipoprotein (apo) A-1 is a major protein of high density lipoproteins (HDL). The gene for apoA-I has been localized to the p11 → q13 region of chromosome 11 by filter hybridization analysis of mouse-human hybrid cell cDNAs containing chromosome 11 translocations utilizing a cloned human apoA-I cDNA probe. The known linkage of apoA-I and apoC-III also permitted the simultaneous assignment of the apoC-III gene to the same region on chromosome 11. Comparison with previously established gene linkages on the mouse and human genome suggests that apoA-I + apoC-III may be linked to the esterase A4 and uroporphyrinogen synthase genes which are present on the long arm of human chromosome 11. The localization of the apoA-I + apoC-III genes in the p11 → q13 region of chromosome 11 represents a definitive chromosomal assignment of a human apolipoprotein gene, and will now anable more detailed analysis of the geneomic organization and linkages of the apolipoprotein genes.

Control system synthesis with response insensitivity

This paper considers the problem of finding a state feedback control law which arbitrarily assigns distinct eigenvalues and achieves output response insensitivity to small plant parameter variations. It is assumed that plant structural parameter dependence is known. Conditions for these objectives are expressed in terms of eigenvectors and equivalent controllability subspaces. A maximum number of possible insensitive terms in the output spectral representation with simultaneous arbitrary eigenvalue assignment is determined, and the problem is shown to be related to the dynamic cover problem. A design procedure employing dynamic compensation is presented. It is shown that dynamic compensation does not influence the number of possible observable, insensitive terms in the output spectral representation, but it can be used to satisfy the required insensitivity conditions. Incorporation of an observer to implement the control law introduces additional sensitivity constraints which can also be satisfied using the design technique.

On the state feedback diagonal decoupling of linear systems described by (A, B, C, E) quadruples

Given a linear multivariable system σ = (A, B, C, E) giving rise to a proper but not strictly proper (m × m), non-singular, transfer function matrix T(a), this paper presents an alternative necessary and sufficient condition for the solvability of the diagonal decoupling and simultaneous pole assignment problem by the use of state feedback and input coordinate transformations using a polynomial matrix approach. The proof of the necessary and sufficient condition is constructive and apart from giving rise to a simple decoupling algorithm it can also be used in order to investigate the structure of the resulting closed-loop decoupled system.

Stability of planar biped models by simultaneous pole assignment and decoupling

Abstract Equations of motion are derived for a planar linkage system of arbitrary length with an actuator at every joint. The system is stabilized by simultaneous pole assignment and decoupling. Estimates of the region of stability are obtained by computation of Lyapunov functions. These methods are applied to obtain numerical results for two biped models.

Algorithm for closed-loop eigenstructure assignment by state feedback in multivariable linear systems

Abstract In this paper an algorithm is presented which greatly facilitates the complete exploitation of state feedback in the assignment of the entire closed-loop eigenstructure of controllable multi-input systems. This algorithm is a generalization of the algorithm of MacLane and Birkhoff (1968) for the computation of a basis for the null space of a matrix and is ideally suited to digital computer implementation. The algorithm readily yields the vectors which are required (Porter and D'Azzo 1978) for the simultaneous assignment of Jordan canonical forms, eigenvectors, and generalized eigenvectors to the plant matrices of closed-loop controllable multivariable linear systems. The effectiveness of the algorithm is illustrated by assigning the entire closed-loop eigenstructure of a third-order two-input discrete-time system in such a way that the resulting closed-loop system exhibits time-optimal behaviour.

Eigenvalue/eigenvector assignment by state-feedback

The problem of simultaneous assignment of closed-loop eigenvalues and eigenvectors using constant complete state-feedback controller is discussed. It is shown that for a given nth-order multivariable system not necessarily completely controllable, associated with every point. λ in the complex plane, there exists a well-defined subspace (in the n-dimensional vector space) within which the eigenvector v corresponding to the eigenvalue at A must lie in order for a real valued controller. assigning the pair (λ, v), to exist. This sub-space is completely determined by the given system and λ. Based on this fact, a necessary and sufficient condition for k pairs of desired closed-loop eigenvalues-eigenvectors, where 1≤κ≤n, to be simultaneously assignable by state-feedback is proposed and a method for determining a controller to assign them is presented. The method is applicable to the case of linearly independent eigenvectors with distinct or repeated eigenvalues as well as that of multiple eigenvectors

Disturbance localization in linear systems with simultaneous decoupling, pole assignment, or stabilization

For a class of constant linear dynamic systems with unmeasurable disturbances, geometric necessary and sufficient conditions are derived for the existence of a state-feedback controller that localizes the disturbances and simultaneously assigns the closed-loop poles or decouples the closed-loop system. These conditions are simple, intuitively appealing, and closely related to the known necessary and sufficient conditions for the separate problems to be solvable alone. Furthermore, it is shown that for these combined problems and for simultaneous disturbance localization and stabilization problems no additional flexibility is afforded by using dynamic compensation instead of static compensation except for the combined problem of disturbance localization and decoupling where the additional flexibility is derived from that for the decoupling problem alone. Under a standard rank assumption, it is established that the combined problem of simultaneously localizing the disturbances, assigning the poles and decoupling the system has no solution. Separate necessary and sufficient conditions are given for the existence of a solution to the combined problem of disturbance localization, stabilization, and decoupling.

The use of random allocation for the control of selection bias

SUMMARY In comparing two treatments, suppose the suitable subjects arrive sequentially and must be treated at once. In such situations, if the experiment calls for fixed treatment numbers, the experimenter can, using his knowledge of the number of treatments that have been assigned, bias the experiment by his selection of subjects. If we consider the method of assigning treatments as an experimental design, Blackwell & Hodges (1957) have shown that the minimax design is the truncated binomial. In this paper we show that random allocation is a restricted Bayes design within the class of Markov designs, and is in many senses preferable to the minimax design. In particular, it is possible for the random allocation design effectively to eliminate the bias asymptotically when the minimax design does not, and in no case will random allocation have a much worse performance than the minimax. In the problem of comparing the effectiveness of two treatments, it is common for the statistician to have the experimenter select 2n subjects suitable for treatment and treat n subjects with each treatment. Clearly, if the experimenter is aware of or guesses which treatment a subject will receive before he selects the subject, then he can, consciously or unconsciously, bias the experiment by his choice; therefore the assignment of treatments to subjects is usually done 'randomly'. Ideally, the 2n subjects will be selected in advance, and the treatment assignments made by random sampling without replacement. This is, however, not always possible. In many cases, suitable subjects arrive sequentially and must be treated immediately or not at all. Two examples which have been cited are clinical trials and cloud seeding experiments. In clinical trials a patient often must be treated as soon as the disease has been diagnosed; in cloud seeding it is physically impossible to collect the subjects (storm clouds) for simultaneous assignment of treatments. In some experiments it may be possible to eliminate this bias by having the selection of suitable subjects done by a third party who is ignorant of the past assignment of treatments, or by defining 'suitability' in a sufficiently objective manner to permit selection without an exercise of judgment. There remain many cases in which the best or only judges available are those involved in administering the treatments. For such situations it is reasonable to ask what strategy the statistician should adopt in the assignment of treatments in order to reduce the expected bias as much as possible. This problem was first considered by Blackwell & Hodges (1957), who have proposed the following model. In order to compare two treatments it is decided to treat 2n subjects, n with treatment A and n with treatment B. Candidates for treatment arrive sequentially, and as each arrives, the experimenter E decides whether or not it is a suitable subject. If it is