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181.
Bresenham’s Algorithm for plotting a two-dimensional line segment is elegant and efficient in its deployment of mid-point comparison and integer arithmetic. It is natural to investigate its three-dimensional extensions. In so doing, this paper uncovers the reason for little prior work. The concept of the mid-point in a unit interval generalizes to that of nearest neighbours involving a Voronoi diagram. Algorithmically, there are challenges. While a unit interval in two-dimension becomes a unit square in three-dimension, “squaring” the number of choices in Bresenham’s Algorithm is shown to have difficulties. In this paper, the three-dimensional extension is based on the main idea of Bresenham’s Algorithm of minimum distance between the line and the grid points. The structure of the Voronoi diagram is presented for grid points to which the line may be approximated. The deployment of integer arithmetic and symmetry for the three-dimensional extension of the algorithm to raise the computation efficiency are also investigated. 相似文献
182.
Vitalija Rubežienė Aušra Abraitienė Julija Baltušnikaitė-Guzaitienė Sandra Varnaitė-Žuravliova Audronė Sankauskaitė Žilvinas Kancleris 《纺织学会志》2018,109(3):358-367
This study presents the investigation of electrically conductive fabrics with low resistivity, coated with formulation containing the conjugated polymer system – poly(3,4-ethylenedioxythiophene)-polystyrene sulphonate (PEDOT-PSS). The samples of fabrics were coated with PEDOT-PSS, using a screen printing method, by different patterns or coating their surface fully with different coating deposit. Methods for measurement of electrostatic properties, reflection and transmission as well as the assessment of electromagnetic radiation (EMR) shielding effectiveness were used for the characterization of electrical properties of developed samples. EMR shielding properties were investigated within 2–12 GHz frequency bands. The highest attenuation of the electromagnetic energy among tested fabrics was obtained on the fabrics fully coated with paste and it depended on deposit considerably. The influence of distribution and deposit of conductive coating on shielding effectiveness of textiles were determined. Correlation between shielding effectiveness and electrostatic properties of developed coated fabrics was also discussed. Electrical properties of samples coated with formulation containing PEDOT-PSS were compared with these of fabrics with metalized yarns, developed by us earlier. The results of EMR shielding measurements showed that fabrics coated with the paste containing conductive polymer system compared to fabrics with in-weaved conductive metalized yarns have certain advantages as EMR shields. 相似文献
183.
Noreen D Willows Vivian Au 《Revue canadienne de la pratique et de la recherche en diététique》2006,67(2):104-107
PURPOSE: Food insecurity appears to be a growing problem for post-secondary students, but little study has been made of the 51 campus-based food banks that exist. In 2003-04, the University of Alberta Campus Food Bank (CFB) distributed hampers intended to supply four days of food to 630 unique clients, of whom 207 (32.8%) were children. The nutritional adequacy of food hampers and cost saving to students were evaluated in the current study. METHODS: Hampers prepared for one adult, and for one adult with one child, were nutritionally evaluated and scored for number of servings according to Canada's Food Guide to Healthy Eating. Two types of hampers were evaluated: those containing only non-perishable items, and those containing non-perishable and perishable items. Hamper contents were priced to establish the cost saving to students. RESULTS: The study revealed that a student with one child would receive up to 58.02 Canadian dollars worth of food in a hamper that contained perishable items. All hampers met the recommended minimum servings for each food group, but were very low in fat and protein from animal sources. CONCLUSIONS: Because students can obtain hampers only twice each month, the CFB is not the solution to food insecurity on campus. Awareness of the issue of post-secondary student food insecurity needs to be raised. 相似文献
184.
Tony K McGhie Michaela C Walton Laura E Barnett Rosheila Vather Harry Martin Joyce Au Peter A Alspach Christine L Booth Marlena C Kruger 《Journal of the science of food and agriculture》2007,87(13):2519-2527
BACKGROUND: The consumption of fruit and vegetables promotes good health by protecting against various degenerative diseases. Even though the constituents responsible are not known, some evidence indicates that the antioxidant properties of fruit and vegetable phytochemicals are responsible. Previous studies have shown that blackcurrant and Boysenberry reduce oxidative stress using in vitro cell systems. The aim of this study was to determine if blackcurrant or Boysenberry drinks could improve measures of oxidative stress and inflammation in an elderly population with below‐average memory abilities. The intervention parallel study was fully blinded with a placebo control. RESULTS: Of the six measures of oxidative stress assessed, only plasma antioxidant capacity significantly increased for both the Boysenberry and blackcurrant treatments compared with the placebo. Plasma malondialdehyde decreased in both the Boysenberry and blackcurrant treatments although the decrease was not statistically significant. Measures of oxidative stress for protein oxidation and lipid peroxidation improved for the berryfruit treatments during the study but were not statistically different from the placebo. CONCLUSION: Long‐term consumption of both the Boysenberry and blackcurrant drinks raised the plasma total antioxidant capacity of the study participants suggesting that Boysenberry and blackcurrant may help protect against oxidative stress‐related health conditions. Copyright © 2007 Society of Chemical Industry 相似文献
185.
In the seismic design of a reinforced concrete (RC) structure, it is necessary to provide not only sufficient strength, but also adequate flexural ductility. This is particularly important to the design of RC beams cast of high‐strength concrete that is inherently more brittle. Eurocode EN1998‐1 directly specifies such minimum flexural ductility. To provide adequate flexural ductility to RC beams, Chinese code GB50011 limits the normalised depth of simplified rectangular stress block at peak resisting moment, whereas American code ACI 318–08 requires that the tension steel strain at peak resisting moment shall not be smaller than 0.004. The essential parameters identified for effective flexural ductility design of RC beams include the maximum difference of tension and compression reinforcement ratios and maximum normalised neutral axis depth at peak resisting moment, as they help to guarantee various flexural ductility requirements. Their relationship with the flexural ductility is studied using a rigorous full‐range moment–curvature analysis procedure. Empirical formulae and tables are also developed to facilitate flexural ductility design of RC beams. A comparison shows that the allowable differences of tension and compression ratios may be smaller than those specified in Eurocode 8 particularly for those cast of high‐strength concrete. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
186.
JE McElhaney MJ Pinkoski D Au KE Lechelt RC Bleackley GS Meneilly 《Canadian Metallurgical Quarterly》1996,14(6):539-544
This study was designed to determine the effect of Type II diabetes mellitus in older adults on two measures of the cell-mediated immune response to influenza vaccination. Twenty-two elderly persons with diabetes mellitus were compared to 20 healthy seniors, all of whom were living independently in the community. Peripheral blood mononuclear cells (PBMC) were challenged in vitro with live influenza virus, pre-vaccination and 4 and 12 weeks post-vaccination. PBMC culture supernatants were assayed for IL-2 activity as a measure of the helper T-cell response to vaccination. The cytotoxic T-lymphocyte response was determined using an assay of granzyme B activity in PBMC lysates. Initial analysis of the data showed increased IL-2 production in post-vaccination PBMC cultures from the diabetic group compared to the healthy group. However, when vaccination histories were used in an analysis of variance, it was found that the difference between the two groups was related to vaccination history. Study subjects vaccinated one year prior to participation in this study compared to those who had not been previously vaccinated, demonstrated a significantly suppressed IL-2 response to vaccination. Type II diabetes mellitus had no effect on the IL-2 response to vaccination. The granzyme B response to vaccination was not significantly affected by previous vaccination and results were similar for the healthy and diabetic elderly groups. 相似文献
187.
Shimada H. Shimomura S. Au R. Miyawaki M. Ohmi T. 《Semiconductor Manufacturing, IEEE Transactions on》1994,7(3):389-393
The resolution enhancement of contact-hole resist patterns featuring precise linear correlation between mask size and resist-pattern size by employing a surface-active developer is presented. The addition of surfactant improves the wettability of the developer, thus enabling the solution to penetrate narrow spaces. The optimum surfactant concentration in developer leads to superior resist performance. This technology for contact-hole patterning results in high resolution, high sensitivity, and a wide process margin for ULSI manufacturing 相似文献
188.
Mining fuzzy association rules in a bank-account database 总被引:1,自引:0,他引:1
This paper describes how we applied a fuzzy technique to a data-mining task involving a large database that was provided by an international bank with offices in Hong Kong. The database contains the demographic data of over 320,000 customers and their banking transactions, which were collected over a six-month period. By mining the database, the bank would like to be able to discover interesting patterns in the data. The bank expected that the hidden patterns would reveal different characteristics about different customers so that they could better serve and retain them. To help the bank achieve its goal, we developed a fuzzy technique, called fuzzy association rule mining II (FARM II). FARM II is able to handle both relational and transactional data. It can also handle fuzzy data. The former type of data allows FARM II to discover multidimensional association rules, whereas the latter data allows some of the patterns to be more easily revealed and expressed. To effectively uncover the hidden associations in the bank-account database, FARM II performs several steps which are described in detail in this paper. With FARM II, the bank discovered that they had identified some interesting characteristics about the customers who had once used the bank's loan services but then decided later to cease using them. The bank translated what they discovered into actionable items by offering some incentives to retain their existing customers. 相似文献
189.
190.