On the state space and frequency domain characterization of H-norm of sampled-data systems

This paper studies the problem of characterization and computation of the H^∞-norm of sampled-data systems using the time-invariant function space model via lifting. With the advantage of time-invariance, the treatment gives an eigenvalue-type characterization, first in the operator form in the frequency domain and then in the Hamiltonian-type finite-dimensional form. The form obtained can be adopted for use with the bisection algorithm for actual computation.     

Chemical synthesis of H-phosphonate DNA without using N-protecting groups

Oligodeoxyribonucleotides were synthesized by using N-unprotected H-phosphonate monomers. It was found that the amino groups of nucleosides were not modified during condensation where benzotriazolyloxy carbonium and phosphonium types of compounds were employed as condensing reagents. The most effective condensing reagent for rapid internucleotidic bond formation was found to be 2-(benzotriazol-1-yloxy)-1,1-dimethyl-2-(pyrrolidin-1- yl)-1,3,2- diazaphospholidinium hexafluorophosphate (BOMP). In the present H-phosphonate approach, 2-benzenesulfonyl-3-(3-nitrophenyl)oxaziridine (BNO) was successfully employed as a new oxidizing reagent for oxidation of the H-phosphonate linkages under anhydrous conditions.     

Optimism, Perceived Risk of Breast Cancer, and Cancer Worry Among a Community-Based Sample of Women.

Optimism is frequently inversely associated with distress; however, less is known about the mechanisms underlying this relationship. Optimism can be defined as having a generalized positive expectancy about the future. The authors hypothesized that a specific expectancy might mediate the relationship between optimism and distress. That model was tested using perceived risk of breast cancer as a specific measure of expectancy and cancer worry as a measure of distress in a community-based sample of 1,366 women. It was hypothesized that optimism would be inversely associated with cancer worry and that perceived risk of breast cancer would mediate the relationship between optimism and cancer worry. Multiple regression analyses revealed that perceived risk partially mediated the relationship between optimism and cancer worry. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A novel component different from endotoxin extracted from Prevotella intermedia ATCC 25611 activates lymphoid cells from C3H/HeJ mice and gingival fibroblasts from humans

A novel immunobiologically active fraction was prepared from a phenol-water extract of Prevotella intermedia ATCC 25611 by Sephadex G-100 column chromatography. The fraction consisted mainly of carbohydrate and protein and was devoid of fatty acid. The fraction showed high-molecular-weight bands (10,000 to 12,000) on deoxycholate polyacrylamide gel electrophoresis (DOC-PAGE) and was scarcely active in a Limulus test. We designated the fraction Prevotella glycoprotein (PGP). The PGP fraction showed strong mitogenicity on splenocytes and cytokine-inducing activities on peritoneal macrophages from both C3H/HeJ and C3H/HeN mice, and it stimulated human gingival fibroblasts to produce cytokines. The activities of the PGP fraction were resistant to heat inactivation (100 degrees C for 1 h) and protease treatments and were scarcely inhibited by polymyxin B. In contrast, the purified lipopolysaccharide fraction (LPS-PCP) extracted from the same bacterium with a phenol-chloroform-petroleum ether mixture, which showed strong Limulus activity and a single low-molecular-weight band (approximately 3,000) on DOC-PAGE, lacked the activities on splenocytes and macrophages from C3H/HeJ mice and human gingival fibroblasts. The activities of the LPS-PCP fraction on cells from C3H/HeN mice were completely inhibited by polymyxin B. The LPS extracted from the same bacterium with hot phenol-water (LPS-PW) exhibited the properties of both the PGP fraction and the LPS-PCP fraction. These findings suggest that the unique bioactivities of the LPS-PW fraction of oral black-pigmented bacteria reported to date, which differed from those of the classical endotoxin, were derived from the PGP fraction and not from the LPS itself.     

A model for blood flow through a stenotic tube

This article deals with the introduction of the modified Casson's fluid model as the true representation for the blood for the steady laminar flow through a small diameter artery with axi-symmetric identical double stenoses in series. The governing equations are solved by using the finite element method. The results for the velocity profiles, the pressure and the wall shear stress distributions in addition to the location and length of the flow reversal zones have been brought out and discussed in reference to the severity of the disease. It has been observed that the non-Newtonian nature of the blood helps in reducing the magnitude of the peak wall shear stress at the throat and the length of the reversed flow regions in the post stenotic dilatation.     

Shifted integration technique in one-dimensional plastic collapse analysis using linear and cubic finite elements

The present study is concerned with the physical explanations of the linear and the cubic finite elements for beams and axisymmetric shells through comparisons of their strain energy approximations with those of the Rigid Bodies-Spring Models which are discrete elements suitable for plastic collapse analysis using the concepts of plastic hinges and hinge lines. The established conditions for the equivalence between these two modellings, which are given as the relations between the locations of the numerical integration points and those of the occurrence of plastic hinges, can be conveniently used in the economical plastic collapse analysis of framed structures and axisymmetric shells where the locations of plastic hinge formations are controlled by the movement of numerical integration points. Some numerical results are shown in order to prove numerically the obtained relations and to verify the validity of the proposed shifting technique of numerical integration points, which is identified as ‘the shifted integration technique’ in the present paper.     

Water and oil repellency of polysiloxanes with highly fluorinated alkyl side chains

A series of fluorinated polysiloxanes (FLSs) with the 3,3,4,4,5,5,6,6,6‐nonafluorohexyl group (C₄F₉C₂H₄? ), 4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,11‐heptadecafluoroundecyl group (C₈F₁₇C₃H₆? ), 3‐(2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,9‐heptadecafluorononanamido) propyl group [HDFNAG; C₈F₁₇(C?O)NHC₃H₆? ], and 3‐(N‐methyl‐2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,9‐heptadecafluorononanamido) propyl group [C₈F₁₇(C?O)N(CH₃)C₃H₆? ] were synthesized. Their homopolymers (homo‐FLSs) and copolymers with dimethylsiloxane (co‐FLSs) were included. The polyester fabrics were treated with these FLSs, and their water and oil repellency was evaluated. These fabrics showed a moderate to good level of water repellency but a poor to zero level of oil repellency, except for those fabrics treated with homo‐FLSs with HDFNAG. The characterization of the surface chemical composition by X‐ray photoelectron spectroscopy showed that the concentration of fluorine at the surface was not particularly high for poly(ethylene terephthalate) films treated with homo‐FLSs with HDFNAG. Differential scanning calorimetry measurements of these FLSs revealed that only homo‐FLSs with HDFNAG had a high melting temperature of 75.7°C. These two measurements suggested that the reason the fabrics treated with homo‐FLSs with HDFNAG showed good oil repellency was not because the concentration of fluorine at the surface was much higher than for the others but because the reorientation of HDFNAG did not take place for its packing after contact with oil. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1085–1091, 2003     

Large-scale underpinning for an underground urban railway station

In many cases, a new railway line is planned beneath existing structures of an urban terminal station. The underpinning method has been developed to respond to such needs. However, this conventional method involves a number of steps and is costly and time-consuming. The steps are: (1) Constructing the cast-in-situ diaphragm walls to keep off the underground water; (2) Supporting the existing structures with the cast-in-situ piles; (3) Excavating the soil under the existing structures; (4) Constructing structures for the new railway; (5) Transferring the loads of the existing structures from the temporary piles onto the newly constructed structure; and (6) Removing the temporary piles. In introducing a new subway line beneath Nagoya station, which is one of the major terminals in Japan, the Central Japan Railway Company made use of temporary structures, cast-in-situ diaphragm walls and piles, as elements of the new structures adopting new measures to increase the accuracy of underground construction. It is suggested that this method can save considerable construction time and cost.     

Dyeing behaviour of Japanese oak silk fibres treated with methacrylamide

Japanese oak silk fibres have been treated with methacrylamide, and the dyeing behaviour when using levelling acid and milling acid dyes has been investigated. Infra-red spectroscopy indicated that a methacrylamide polymer skin was produced on the fibre surface at high levels of polymer add-on. The methacrylamide polymer skin was dyed with the milling acid dye, although not dyed with the levelling acid type. The penetration of the levelling acid dye into the fibres was not interrupted by the polymer skin.     

Genetic algorithm-based method for contingency screening in power systems

This paper proposes an application of genetic algorithm (GA) to contingency screening in power systems. The contingency selected by the GA-based screening method is the double line outage which has the risk of causing transient instability. Generally, the contingency screening problem including multiple outage can be interpreted as the combinatorial optimization one for searching the combination of single outages which makes the system insecure. Therefore, GA which is one of the probabilistic searches for combinatorial problems, is applicable for such contingency screening problems. In the GA-based contingency screening method, a double line outage is represented as a chromosome. The fitness of the chromosome for environment is defined by using the transient energy function of power systems. The new procedure for avoiding the loss of important outage during contingency screening is developed and embedded in the proposed method by using the theorem of schema for GA. The validity of the proposed method is confirmed by applying it to a 6-machine 30-bus 40-line system. The result shows that the GA-based contingency screening has the potential for practical use.