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Technological Limits (technological + limit)

Distribution by Scientific Domains

Engineering	50%

Selected Abstracts

Accelerated Reliability Qualification in Automotive Testing

QUALITY AND RELIABILITY ENGINEERING INTERNATIONAL, Issue 2 2004
Alex Porter
Abstract Products must come to market quickly, be more reliable and cost less. The problem is that statistical measures take time. There is a clear need for actionable information about the robustness or durability of a product early in the development process. In a Failure Mode Verification Test (FMVT), the analysis is not statistical but is designed to check two assumptions. First, that the design is capable of producing a viable product for the environments applied. Second, that a good design and fabrication of the product would last for a long period of time under all of the stresses that it is expected to see and would accumulate stress damage throughout the product in a uniform way. Testing a product in this way leads to three measures of the product's durability: (1) design maturity, the ratio between time to first failure and the average time between failures after the first failure; (2) technological limit, the time under test at which fixing additional failures would not provide a significant improvement in the life of the product; and (3) failure mode histogram, which indicates the repeatability of failures in a product. Using techniques like FMVT can provide a means of breaking the tyranny of statistics over durability and reliability testing in a competitive business climate. Copyright © 2004 John Wiley & Sons, Ltd. [source]

THE ECONOMICS OF HOMELAND SECURITY EXPENDITURES: FOUNDATIONAL EXPECTED COST-EFFECTIVENESS APPROACHES

CONTEMPORARY ECONOMIC POLICY, Issue 1 2007
SCOTT FARROW
While most economists expect some marginal conditions to result from basic expected value models involving government expenditures and homeland security investments, such models are not readily found in the literature. The article presents six basic models that all incorporate uncertainty; they also capture various problems involving technological limits, behavioral interactions, false negatives and false positives, and decision making with uncertainty and irreversibility. Recent reviews of homeland security programs by the U.S. Government Accountability Office are used to illustrate the relevance of the models.(JEL H100) [source]

Design techniques of two-layer architectures for WDM optical networks

INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 2 2001
Andrea Borella
Abstract A general method for designing multilayered WDM optical networks, based on the combined use of single-and multi-hop connection modes, is presented. It takes into account variable values for the number of users and wavelengths in each cluster. Closed form expressions are derived for the transmission capacity and the optimum number of channels for intra-cluster communications, either in the case of uniform or non-uniform traffic distribution. The analytical approach is particularly useful in the presence of constraints on the number of wavelengths, due to technological limits or non-linear phenomena, when sub-optimal solutions must be necessarily addressed. The proposed method is integrated with the adoption of well-known selection procedures, like simulated annealing or genetic algorithms, to reduce the computational effort. Copyright © 2001 John Wiley & Sons, Ltd. [source]

Evaluation of the Sysmex Xe-2100® hematology analyzer in hospital use

JOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 4 2003
Danièle Nakul-Aquaronne
Abstract The Sysmex XE-2100® (Sysmex Corp. Kobe, Japan) is a latest-generation hematology analyzer. Its optical and electrical measuring technology is improved by the addition of flux cytometry, fluorescence, and differential lysis. Its analytical performance in terms of precision, reproducibility, linearity, carryover, and time stability was found to be entirely satisfactory. In addition, the results of 500 complete blood counts and differentials correlated perfectly with those obtained by the Coulter STKS® (Beckman Coulter, Villapointe, France). The comparison of 500 leukocyte differential count results analyzed in parallel with optical microscopy and the XE-2100® were surprising, and favorable to the XE-2100®. This analyzer provides the user with an undeniable feeling of security concerning its reliability in detecting and identifying anomalies in the automated leukocyte differential count. With a sensitivity of 96%, a negative predictive value (NPV) of 98%, and a false-negative (FN) rate of 4%, the XE-2100® has perhaps reached the technological limits for a machine performing morphological recognition of normal and pathological blood cells. J. Clin. Lab. Anal. 17:113,123, 2003. © 2003 Wiley-Liss, Inc. [source]