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101.
A simple algorithm utilizing the factoring theorem and other elementary network reductions is available to determine network reliability in a number of different forms. This paper describes a computer-based implementation of such an algorithm housed in a hypermedia environment. The environment can provide for both the formulation and the solution of reliability problems. In our treatment the user draws the network interactively on the computer screen and clicks an on-screen button to perform the reliability analysis. This provides an alternative to manual calculations that become tedious or impossible with networks which are neither series-parallel nor extremely small.  相似文献   
102.
A method for calibrating quartz crystal thickness monitors is described, which makes use of 20 nm platinum sputtered colloidal gold particles. The actual thickness is measured on transmission electron micrographs of gold particles protruding from the edge of fractured, rolled up, carbon films. In the range up to ~10 nm, the measured thickness for platinum films is ~17% larger than the figures calculated from mass thickness equations.  相似文献   
103.
Thinking with Diagrams in Architectural Design   总被引:1,自引:0,他引:1  
The paper discusses the use of freehand diagrams inarchitectural design. It examines the roles ofdiagrams in various contexts: pedagogical books,design studies, designers' introspective accounts andempirical studies of drawing in design. It offersseveral examples of thinking with diagrams in designand concludes with a discussion of the requirementsfor computational support for the diagrams in designthinking.  相似文献   
104.
State space exploration is often used to prove properties about sequential behavior of Finite State Machines (FSMs). For example, equivalence of two machines is proved by analyzing the reachable state set of their product machine. Nevertheless, reachability analysis is infeasible on large practical examples. Combinational verification is far less expensive, but on the other hand its application is limited to combinational circuits, or particular design schemes. Finally, approximate techniques imply sufficient, not strictly necessary conditions.The purpose of this paper is to extend the applicability of purely combinational checks. This is generally achieved through state minimization, partitioning, and re-encoding the FSMs to factor out their differences. We focus on re-encoding. In particular, we present an incremental approach to re-encoding for verification that transforms the product machine traversal into a combinational verification in the best case, and into a computationally simpler product machine traversal in the general case.Experimental results demonstrate the effectiveness of this technique on medium-large circuits where other techniques may fail.  相似文献   
105.
The solid state crystallization in drawn thermoplastic polyimide films is studied as a function of draw ratio (DR) under the effect of vapor grown carbon fiber nanoinclusions. The nucleating effect of the nanoinclusions coupled with the orientation effect of drawing generates a unique orientated layered lamellar structure, characteristic of smectic‐like mesophase. The degree of draw induced orientated crystallization increases with the content of nanoinclusions and with the DR, and is reflected in the mechanical behavior of the film. Generally, the Young's modulus and the yield point of the drawn crystalline films in the drawing direction are significantly higher compared with the noncrystalline counterparts. POLYM. ENG. SCI., 2009. © 2008 Society of Plastics Engineers  相似文献   
106.
The ambient oxygen ingress rate method (AOIR) is an alternative method to Ox‐Tran for measuring the oxygen transmission rates (OTR) of whole packages. The objective of the present work was (a) to compare OTR values obtained by the two methods, and (b) to evaluate the use of the AOIR method for measuring OTR at realistic food storage temperatures and humidity levels. The AOIR method gave equal OTR values compared to the Ox‐Tran method for the five different types of whole packages used in the experiment, with OTR values in the range 0.06–1.48 ml O2/day. The repeatability of the AOIR method measured on an HDPE bottle was ±2.6% of the measured value in this experiment. This is slightly higher than the general specifications of the Ox‐Tran method (1% of reading for packages). However, the AOIR method can be considered to be a reliable, precise and cheap alternative method to the Ox‐Tran method for measuring OTR of whole packages. The capacity of the method is also high. The AOIR method showed satisfactory results when comparing OTR for packages tested under realistic food storage conditions covering 23°C/50% relative humidity (RH) and at 4°C/60% RH on the outside, combined with water (100% RH) or dry air inside the packages. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
107.
Why do people's impulse controls break down during emotional distress? Some theories propose that distress impairs one's motivation or one's ability to exert self-control, and some postulate self-destructive intentions arising from the moods. Contrary to those theories, three experiments found that believing that one's bad mood was frozen (unchangeable) eliminated the tendency to eat fattening snacks (Experiment 1), seek immediate gratification (Experiment 2), and engage in frivolous procrastination (Experiment 3). The implication is that when people are upset, they indulge immediate impulses to make themselves feel better, which amounts to giving short-term affect regulation priority over other self-regulatory goals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
108.
Advancements in the fields of genomic screening, molecular pathology and clinical research have resulted in a major increase in the demand for high quality DNA and RNA. This escalating demand has resulted in a sample preparation bottleneck and an emphasis on the development of new technologies to automate the purification process. Gentra has developed the AUTOPURE LS™ nucleic acid purification instrument, a platform capable of high-throughput sample purification from large samples, such as 10 mL whole blood. This article presents data showing the equivalency of DNA purified using manual and automated processing.  相似文献   
109.
In Part I, the author assesses mediation's trade-off between rights and needs, focusing on the problematic nature of need satisfaction as a benchmark for successful mediation. Part II suggests that needs, unlike rights, are fundamentally subjective and that minorities and other traditionally marginalized peoples may define their needs more minimally than their White counterparts. It further summarizes data demonstrating that minorities experience greater satisfaction in mediation than Whites, even though they achieve objectively worse outcomes. Part III explores the validity of need satisfaction as the litmus test for proper or effective mediation, noting that individual need may be tainted by prejudice or colored by an improper interpretation of background legal norms and entitlements. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
110.
Starches from cowpea and chickpea seeds were isolated and their properties were compared with those of commercial yellow pea starch. Amylose contents were 25.8%, 27.2%, and 31.2%, and the volume mean diameter of granules, determined in the dry state, were 15.5, 17.9, and 33.8 μm for cowpea, chickpea and yellow pea starches, respectively. All three legume starches showed a C-type X-ray diffraction pattern and two-stage swelling pattern. Amylopectin populations were isolated and the unit chain profiles were analyzed by HPLC after debranching with pullulanase. The degree of polymerization (DP) of short chain populations was about 6–50 and the populations of long chain had a DP of 50–80. Cowpea showed a lower weight ratio of short:long chains than chickpea and yellow pea starches. The larger portion of long side chains in cowpea amylopectin can be correlated with a higher gelatinization temperature, greater pasting peak and a slight difference in crystalline structure found for cowpea starch. Chickpea and yellow pea starches exhibited similarity in unit chain profile of amylopectin as well as in gelatinization temperature and pasting profile, while they differed in amylose content, particle size and syneresis. It is assumed that the chain length distribution of amylopectin has a large influence on starch properties.  相似文献   
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