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81.
82.
A fault does not necessarily cause an immediately effective error, thereby leading to a system failure. Many experiments have shown that most hardware faults do not cause immediately detectable errors. In fact, it has been found that a significant proportion of the faults injeected during the experiments remained latent, i.e. went undetected. In this paper we call the phenomenon the latency problem. The paper describes an experimental study of the latency problem, with the aim of validating the analytical model developed by Soh and Dillon [Microelectron. Reliab. 36, 1223 (1996)]. 相似文献
83.
EL Vodovozova GP Gayenko VI Razinkov EY Korchagina NV Bovin JG Molotkovsky 《Canadian Metallurgical Quarterly》1998,44(3):543-553
The overexpression of lectins by malignant cells was applied for in vitro targeting of liposomes equipped with a saccharide vector and loaded in the lipid phase with a lipid derivative of anticancer agent sarcolysine. The lectin specificity of human leukemia HL-60 and human lung adenocarcinoma ACL cells was revealed by tests with fluorescein-labeled sugar probes. With the help of fluorescent lipid dye it was shown that active saccharide ligands increased the level of the vectored liposome binding to malignant cells by 50-80% as compared to liposomes without vector or with inactive one. The degree of liposome/cell membrane fusion was monitored fluorometrically and was shown to be complete and independent of the vectors. The targeted drug-loaded liposomes had the cytotoxic activity 2-4 times higher as compared to the vector-free ones. 相似文献
84.
N Saha CK Heng BP Mozoomdar EM Reuben HT Soh PS Low JS Tay Y Liu S Hong 《Canadian Metallurgical Quarterly》1995,117(1):33-42
We examined the genotypes of ALDH2, ADH2, ADH3 and P-4502E1 loci of alcoholics and nonalcoholics. Also we compared the frequencies of the homozygous ALDH2*1/1 genotype and heterozygous ALDH2*1/2 genotypes in alcoholics. Our study reported differences in the allelic frequencies of ALDH2, ADH2 and ADH3 loci between alcoholics and nonalcoholics. For alcoholics, it was indicated that ADH2 and ADH3 plays an important role for alcoholism. For genotypes of P-4502E1, no significant difference was observed between alcoholics and nonalcoholics. Alcoholics with the heterozygous ALDH2*1/2 genotype had significantly higher frequency of the ADH2*1 than that of alcoholics with ALDH2*1/1 genotype. Concerning the alcoholics with the heterozygous ALDH2*1/2 genotype, we assumed that ADH2*1 plays a role for the development of alcoholism. 相似文献
85.
JJ Brokaw GW White P Baluk GP Anderson EY Umemoto DM McDonald 《Canadian Metallurgical Quarterly》1998,19(4):598-605
The results of two previous studies have shown that implant porosity can be used to increase both the measured diffusion coefficients and the vascularity within the tissue encapsulating long-term subcutaneous implants. This study investigates the hypothesis that the analyte concentrations within the tissue surrounding porous implants will respond more quickly to changes in plasma levels than does the densely packed, avascular fibrous capsule surrounding nonporous implants. The average concentration of lissamine-rhodamine was measured in tissue within 100 microm of the following implants at four different times following injection of the tracer: PVA-skin, PVA-5, PVA-60, PVA-700 (polyvinyl alcohol nonporous, 5 microm, 60 microm, and 700 microm mean pore sizes, respectively) and PTFE-0.5 and PTFE-5 (polytetrafluoroethylene 0.5 microm and 5 microm mean pore sizes, respectively). The results were compared to those of unimplanted subcutaneous tissue (SQ). In addition, the data were analyzed with a simple two-compartment model in which a tissue response time constant (taup) was extracted. As in the case of vascular density, the cellular dimension of the PVA-60 pore sizes produced surrounding tissue with the optimum response times to changes in plasma concentrations. The concentrations of rhodamine within the tissue surrounding the PVA-60 implant were the highest at all time points and responded to the change in plasma rhodamine concentration approximately three times more quickly (taup = 764 s) than the fibrous tissue encapsulating the nonporous PVA-skin (taup = 2058 s) and more than twice as quickly as SQ (taup = 1627 s). The overall mass transfer rate between plasma and the tissue surrounding the different implants calculated from the permeability and density of vessels from the previous study correlated very well (r2 = 0.7, p < .02, slope of 0.98) with the reciprocal of the tissue response time constant (taup). 相似文献
86.
Twenty-seven patients who had a unilateral displaced intra-articular fracture of the calcaneus were managed with a cast instead of with reduction or an operation. The clinical result after a mean of six years (range, two to ten years) was excellent in five patients, good in five, fair in seven, and poor in ten. The sixteen patients who were re-examined for this study and for whom the gait was analyzed demonstrated abnormalities in ground-reaction force with regard to vertical force (F3) and temporal force factors (T2, T3, T6, and T9). Analysis of temporal and distance factors showed a trend toward a decreased proportion of single-limb support on the involved side. Three-dimensional motion analysis of the ankle and hindfoot was performed with electrogoniometers as the subject walked on a level surface, on a 10-degree side-slope, and up and down stairs. Motion was decreased in the sagittal, coronal, and transverse planes during walking on level ground and on a side-sloping surface. Significant decreases in motion in these planes were also seen during walking up and down stairs. Although these patients did not have a subsequent reconstructive operation, most had a residual functional deficit. 相似文献
87.
Kok Kiong Tan Tong Heng Lee Chai Yee Soh 《Education, IEEE Transactions on》2002,45(2):128-134
This paper presents the development of an Internet-based system to allow monitoring of important process variables from a distributed control system (DCS). The system is formulated as an add-on to an undergraduate experiment on the development of a desktop DCS. This paper describes the hardware and software design considerations which enable the users to access the process variables on the DCS, remotely and effectively, using only a commonly available Web browser 相似文献
88.
Optimal Layout of Bridge Trusses by Genetic Algorithms 总被引:5,自引:0,他引:5
Chee-Kiong Soh & Jiaping Yang 《Computer-Aided Civil and Infrastructure Engineering》1998,13(4):247-254
In this paper we present an approach to the layout and shape-optimization problem of bridge truss structures using genetic algorithms. The objective is to find an optimal layout design that will have minimum weight or material volume, subject to performance constraints related to member stresses, joint displacements, and member buckling. An automated two-stage optimization search process, which integrates structural analysis by finite-element method, genetic algorithms, and cognitive topology patterns (domain knowledge), is developed to solve the optimal problem. Two examples concerning bridge truss structure are investigated to demonstrate the effectiveness of the proposed method in solving these layout-optimization problems. 相似文献
89.
The robust stability of discrete-time systems formulated in terms of the delta (δ) operator is discussed. That is, given the nominal characteristic equation P (δ) of a discrete-time system, it is of interest to know how much the coefficients can be perturbed while preserving stability. A procedure to obtain the maximum intervals for a perturbed polynomial P (δ) to still be stable is presented 相似文献
90.
This paper examines the role of the Singapore Government in Singapore's computerization efforts. In restructuring Singapore's economy and sharpening its competitive edge, information technology (IT) is singled out as one of the economic boosting engines whose dynamic, innovative role will change the economic and social fabric of society leading to a better quality of life for Singaporeans. The government and its agencies have deliberately intervened in the IT diffusion process through proactive IT policies, effective regulations and implementation. The national computerization plans, namely, the National IT Plan and the IT2000 Report, contain a set of IT strategic initiatives. Although the socioeconomic conditions and the cultural factors do have a significant influence on the IT diffusion process, an understanding of roles different institutions play and the various institutional policies will provide a better assessment of the impacts of IT on Singapore's information economy. 相似文献