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81.
Presents a novel approach for automating the timing design of interfaces between VLSI chips in microcomputer systems. The Prolog-based expert system, called TDS (for timing design system), incorporates the heuristic knowledge of the hardware designer. TDS is a rule-based system that interprets the specification sheets of VLSI chips and can synthesize, diagnose, and verify timing charts at the expert's level. The system uses a functional model based on timing specifications, not the structural information. TDS can model other interfaces that are based on timing specifications, such as standard bus interfaces  相似文献   
82.
BACKGROUND: Medicinal plants commonly used and traded in Turkey were monitored for their cadmium and selected micronutrient (copper, iron, manganese and zinc) content. RESULTS: Cadmium was not detected in any sample of licorice extract, linden flowers or nettle leaves. However, in the rest of the samples, cadmium was found in the range of 7–126 µg kg?1, with the highest concentration in chamomile leaf. Of all the monitored trace elements, the highest concentration found was 520 mg kg?1 iron in zahter. The highest copper, manganese and zinc concentrations were found in rose hips (24 mg kg?1), Turkish oregano (58 mg kg?1) and zahter (50 mg kg?1), respectively. CONCLUSION: The results of the present study reveal that cadmium and trace element concentrations in medicinal plants commonly used as traditional medicines in Turkey are well below the critical levels. Copyright © 2007 Society of Chemical Industry  相似文献   
83.
A simple and accurate solvent extraction method was developed for the separation and preconcentration of trace levels of copper(II) in water using N-o-vanillidine-2-amino-p-cresol prior to its determination using flame atomic absorption spectrometry. Analytical parameters such as the pH of the aqueous phase, extraction time, concentration of the reagent, concentration of the nitric acid back extraction agent, volumes of aqueous phase and back extraction agent, and concomitant ions on the extraction yield of the copper(II) were investigated and optimized. Under the optimal conditions, the detection limit (3σ) was 0.61 µ g L?1 for a 25 mL blank solution, yielding a preconcentration factor of 12.5. The method was succesfully applied to the determination of copper(II) in tap water, river water, and seawater. The accuracy of the method was verified by analyzing two certified reference materials and spiked water samples. The results obtained were in agreement with the certified values and the recoveries for spiked water samples were between 98 and 112%.  相似文献   
84.
Networks and Spatial Economics - The hub location problem (HLP) is a special type of the facility location problem with numerous applications in the airline industry, postal services, and computer...  相似文献   
85.
Passenger flow forecasting is an essential part of transportation systems. Neural networks in the transportation field have been applied to passenger demand prediction. In this paper, we developed two hybrid methods, known as parlimentary optimization algorithm-artificial neural network (POA-ANN), and intelligent water drops algorithm-ANN (IWD algorithm-ANN). In addition, we applied the proposed algorithms to illustrate the effect of precise prediction for passenger queues. We mainly focus on predicting passenger demand by comparing the genetic algorithm-ANN (GA-ANN) with POA-ANN and IWD-ANN. The results of prediction methods suggest that both POA-ANN and IWD-ANN provide a better forecasting performance, which is obtained via mean square error (MSE), than GA-ANN in the field of passenger flow prediction. This study illustrates that the newly adopted algorithms exhibit good performance for passenger prediction.  相似文献   
86.
N‐methacryloyl‐(L )‐alanine (MALA) was synthesized by using methacryloyl chloride and alanine as a metal‐complexing ligand or comonomer. Spherical beads with an average diameter of 150–200 μm were obtained by suspension polymerization of MALA and 2‐hydroxyethyl methacrylate (HEMA) conducted in an aqueous dispersion medium. Poly(HEMA–MALA) beads were characterized by SEM, swelling studies, surface area measurement, and elemental analysis. Poly(HEMA–MALA) beads have a specific surface area of 68.5 m2/g. Poly(HEMA–MALA) beads with a swelling ratio of 63%, and containing 247 μmol MALA/g were used in the removal of Hg2+ from aqueous solutions. Adsorption equilibrium was achieved in about 60 min. The adsorption of Hg2+ ions onto PHEMA beads was negligible (0.3 mg/g). The MALA incorporation into the polymer structure significantly increased the mercury adsorption capacity (168 mg/g). Adsorption capacity of MALA containing beads increased significantly with pH. The adsorption of Hg2+ ions increased with increasing pH and reached a plateau value at around pH 5.0. Competitive heavy metal adsorption from aqueous solutions containing Cd2+, Cu2+, Pb2+, and Hg2+ was also investigated. The adsorption capacities are 44.5 mg/g for Hg2+, 6.4 mg/g for Cd2+, 2.9 mg/g for Pb2+, and 2.0 mg/g for Cu2+ ions. These results may be considered as an indication of higher specificity of the poly(HEMA–MALA) beads for the Hg2+ comparing to other ions. Consecutive adsorption and elution operations showed the feasibility of repeated use for poly(HEMA–MALA) chelating beads. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1222–1228, 2006  相似文献   
87.
This paper presents the results of a research investigation undertaken to develop methodologies and techniques that will reduce the cost and time of the design, manufacturing and assembly of mechanical conveyor systems used in the food and beverage industry. The improved methodology for design and production of conveyor components is based on the minimisation of materials, parts and costs, using the rules of design for manufacture and design for assembly. Results obtained on a test conveyor system verify the benefits of using the improved techniques. The overall material cost was reduced by 19% and the overall assembly cost was reduced by 20% compared to conventional methods.  相似文献   
88.
Eighteen students (K-11th grade) with emotional/behavioral disorders who were at-risk for change of placement to more restrictive settings participated. Construct validity of functional behavioral assessment (FBA) was assessed with a multifunction-multimethod matrix that showed excellent convergent and divergent agreement with combined FBA methods and functional analysis results. Treatment validity was assessed with random assignment to either a FBA with consultation condition (FBC) or to a behavioral consultation without FBA condition (BC). Growth curve analysis showed a significant decrease in inappropriate behavior from baseline to treatment for both treatment groups compared to a control group. The efficiency of teachers' implementation effected treatment validity. Effect sizes showed that regardless of treatment condition that interventions with good fidelity realized the largest effect (d = -1.14). Social and habilitative validity was assessed with telephone interviews conducted a year after treatment. Sixty-five percent attributed the students' problem behaviors to their thoughts or feelings, whereas only 25% attributed it to classroom variables. Many (57%) indicated the most helpful intervention would be individual counseling, whereas only 14% indicated a more involved classroom management plan would be useful. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
89.
The sorption of anionic ligands such as I, Br, and SCN onto diaminoethyl–sporopollenin (DAE–sporopollenin) was investigated in both column and batch experiments at room temperature. The isotherm binding constants suggest that the resin is most efficient at the binding of I compared with Br or SCN. The general ligand sorption affinity series observed was I > Br > SCN. This ligand sorption could be described by considering the hydration of ions in the exchanger. The sorption behavior of the ligand exchanger and the possibilities of selectively removing and recovering ligands are discussed on the basis of their chemical and complexing properties. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 771–774, 1998  相似文献   
90.
The S. cerevisiae genome is the most well-characterized eukaryotic genome and one of the simplest in terms of identifying open reading frames (ORFs), yet its primary annotation has been updated continually in the decade since its initial release in 1996 (Goffeau et al., 1996). The Saccharomyces Genome Database (SGD; www.yeastgenome.org) (Hirschman et al., 2006), the community-designated repository for this reference genome, strives to ensure that the S. cerevisiae annotation is as accurate and useful as possible. At SGD, the S. cerevisiae genome sequence and annotation are treated as a working hypothesis, which must be repeatedly tested and refined. In this paper, in celebration of the tenth anniversary of the completion of the S. cerevisiae genome sequence, we discuss the ways in which the S. cerevisiae sequence and annotation have changed, consider the multiple sources of experimental and comparative data on which these changes are based, and describe our methods for evaluating, incorporating and documenting these new data.  相似文献   
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