Three Direct Methods in Linear Programming

A new method for parameter identification of large dynamic systems is described, and the broad outlines of an automated procedure presented. The dynamic system may consist of an arbitrary assemblage of structural and mechanical elements for which numerical values of certain “design parameters” are to be determined. This “design” problem is formulated in discrete mathematical programming terms as a problem in constrained minimization. The method of solution is indirect, requiring first the time-wise synthesis of element response functions to optimally satisfy the stated design problem. The design parameters subsequently are identified by a function matching procedure in the time domain. For a large class of problems the optimal synthesis phase reduces to a problem in linear programming, while the parameter identification phase is a matter of least squares curve fitting for each design element independently. The great computational advantage over direct methods results from elimination of the need to repetatively solve the system dynamics during the identification process. Thus the computational size of the linear programming problem does not depend on the kinematic degrees of freedom of the dynamic system. An illustrative example involving 32 design parameters is presented.

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Two direct methods in linear programming

European Journal of Operational Research ◽

10.1016/s0377-2217(00)00083-7 ◽

2001 ◽

Vol 131 (2) ◽

pp. 417-439 ◽

Cited By ~ 25

Author(s):

Nebojša V. Stojković ◽

Predrag S. Stanimirović

Keyword(s):

Linear Programming ◽

Direct Methods

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Gold liposomes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100166956 ◽

1996 ◽

Vol 54 ◽

pp. 898-899

Author(s):

James F. Hainfeld

Keyword(s):

Direct Methods ◽

Important Class ◽

Double Bonds ◽

Membrane Phospholipids ◽

Essential Ingredient ◽

Lipid Structures

Lipids are an important class of molecules, being found in membranes, HDL, LDL, and other natural structures, serving essential roles in structure and with varied functions such as compartmentalization and transport. Synthetic liposomes are also widely used as delivery and release vehicles for drugs, cosmetics, and other chemicals; soap is made from lipids. Lipids may form bilayer or multilammellar vesicles, micelles, sheets, tubes, and other structures. Lipid molecules may be linked to proteins, carbohydrates, or other moieties. EM study of this essential ingredient of life has lagged, due to lack of direct methods to visualize lipids without extensive alteration. OsO4 reacts with double bonds in membrane phospholipids, forming crossbridges. This has been the method of choice to both fix and stain membranes, thus far. An earlier work described the use of tungstate clusters (W11) attached to lipid moieties to form lipid structures and lipid probes.

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High performance Nanogold™-in situ hybridzation and its use in the detection of hybridized and PCR-amplified microscopical preparations

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100166944 ◽

1996 ◽

Vol 54 ◽

pp. 896-897

Author(s):

G. W. Hacker ◽

I. Zehbe ◽

J. Hainfeld ◽

A.-H. Graf ◽

C. Hauser-Kronberger ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Messenger Rna ◽

High Performance ◽

Detection System ◽

Direct Methods ◽

Genetic Alterations ◽

Chain Reaction ◽

Protein Encoding ◽

Polymerase Chain

In situ hybridization (ISH) with biotin-labeled probes is increasingly used in histology, histopathology and molecular biology, to detect genetic nucleic acid sequences of interest, such as viruses, genetic alterations and peptide-/protein-encoding messenger RNA (mRNA). In situ polymerase chain reaction (PCR) (PCR in situ hybridization = PISH) and the new in situ self-sustained sequence replication-based amplification (3SR) method even allow the detection of single copies of DNA or RNA in cytological and histological material. However, there is a number of considerable problems with the in situ PCR methods available today: False positives due to mis-priming of DNA breakdown products contained in several types of cells causing non-specific incorporation of label in direct methods, and re-diffusion artefacts of amplicons into previously negative cells have been observed. To avoid these problems, super-sensitive ISH procedures can be used, and it is well known that the sensitivity and outcome of these methods partially depend on the detection system used.

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