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171.
Masaki Oono El‐Sayed Atlam Masao Fuketa Kazuhiro Morita Jun‐ichi Aoe 《Software》2003,33(13):1229-1249
A double‐array is a well‐known data structure to implement the trie. However, the space efficiency of the double‐array degrades with the number of key deletions because the double‐array keeps empty elements produced by the key deletion. This paper presents a fast and compact elimination method of empty elements using properties of the trie nodes that have no siblings. The present elimination method is implemented by C language. From simulation results for large sets of keys, the present elimination method is about 30–330 times faster than the conventional elimination method and maintains high space efficiency. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
172.
Sodium-bismuth titanate Na0.5Bi4.5Ti4O15 (NBT) and barium bismuth titanate BaBi4Ti4O15 (BBT) and their solid solutions were prepared by solid state reaction of the constituent oxides. The room temperature structural characteristics were determined by X-ray diffraction and the dielectric properties investigated in a wide range of temperatures (20–750°C) and frequencies (1 kHz–1 MHz). As the barium content increases, the unit cell change from orthorhombic to pseudo-tetragonal, the paraelectric to ferroelectric phase transition decreases from 655°C to 400–420°C and a relaxor-like behaviour is observed for high barium contents. Depending on the composition, dielectric data were fitted using both classical (low Ba) and modified Curie-Weiss law for relaxors (high Ba). 相似文献
173.
The electron backscattering factor was measured from 24 different elements at low primary beam energy (250-5,000 eV). The results were compared with Monte Carlo simulations from a variety of freely available programs and an in-house developed program. The results suggest that a thin film of oxide can modify the backscattering factor at low primary energy. In addition, a number of problems have been identified with the freely available programs. 相似文献
174.
Li Xin Hijazi Ihab Xu Mengchao Lv Haibin El Meouche Rani 《Multimedia Tools and Applications》2016,75(24):17449-17464
Multimedia Tools and Applications - With increasing demands for indoor GIS, indoor routing and analysis attracts attention from both GIS and architecture worlds. This paper aimes to provide... 相似文献
175.
Emna B. Saafi‐Ben Salah Guido Flamini Amira El Arem Manel Issaoui Samia Dabbou Leila BenYahia Ali Ferchichi Mohamed Hammami Lotfi Achour 《International Journal of Food Science & Technology》2012,47(9):1903-1908
This paper reports a discrimination study based on the physico‐chemical characteristics, fatty acids and profile of volatile compounds of the seeds from seven date palm varieties (Phoenix dactylifera L.) grown in Tunisia. Date seeds contained 10.49–14.76% moisture; 6.28–11.2% fat (on a dry weight basis); 2.67–12.85% protein; 0.91–6.06% reducing sugar; 0.61–2.98% sucrose and 0.97–1.17% ash. Gas liquid chromatography revealed that the oil fraction of the date palm seeds contained eighteen fatty acids, with oleic acid (30.77–42.50%) and lauric acid (18.51–27.48%) as the main unsaturated and saturated ones. Volatile profile showed differences among varieties. In total, forty‐five compounds were identified, mainly alcohols, aldehydes and unsaturated hydrocarbons ones. This study provides evidence that the seeds of date may be a potential source of valuable nutrients with interesting functionality. 相似文献
176.
Hicham Lakrafli Soufiane Tahiri Abderrahmane Albizane Souad El Houssaini Mohamed Bouhria 《Energy Efficiency》2017,10(5):1189-1199
In this work, we investigate the effect of the thermal insulation by leather wastes (wet-blue chrome shavings and buffing dust) and carpentry wastes (wood shavings and sawdust) on the energy consumption of a model building using the average climatic data of the city of Casablanca (Morocco). For this study, we used the dynamic thermal simulation tool “TRNSYS 16” which predicts the thermal behavior of building and systems associated with it. Using this software, we evaluated the effect of the above material wastes on thermal comfort and building energy consumption. The type and the thickness of the materials were considered as variants to choose the better solution. The average temperatures of building supposed thermally insulated compared to those obtained without insulation clearly show the thermal insulation ability of tested materials during the cold and warm periods of the year. Increasing the thickness of the insulator makes locals increasingly comfortable. Because of their performance, leather and carpentry wastes can compete with conventional insulating materials such as polystyrene and cork. 相似文献
177.
Obead Yaseen Maher M. El‐Masri Wasim S. El Nekidy Derrick Soong Mohammed Ibrahim John W. Speirs Albert Kadri 《Hemodialysis international. International Symposium on Home Hemodialysis》2013,17(3):434-440
Hemodialysis catheter (HDC) dysfunction due to thrombosis is common, and dysfunction incidence can reach up to 50% within 1 year of use. Although administration of intraluminal alteplase (tissue plasminogen activator [tPA]) is the standard of practice to pharmacologically restore HDC function, there are no evidence‐based guidelines concerning the optimal tPA dose. The purpose of this study was to compare the efficacy of 1.0‐mg vs. 2.0‐mg tPA dwell protocols in restoring the HDC function in thrombotic dysfunctional catheters. A retrospective, single‐center study was conducted on two independent cohorts of patients; the first (n = 129) received 2.0 mg tPA/catheter lumen, while the second (n = 108) received 1.0 mg tPA/catheter lumen. Kaplan–Meier and Cox regression analyses were performed to compare the catheter survival time between patients who received 1.0 mg tPA and those who received 2.0 mg tPA. Catheter removal occurred in 25 (19.4%) of those catheters treated with 1.0 mg tPA compared with 11 (10.2%) of catheters treated with 2.0 mg tPA (P = 0.05). The hazard ratio (HR) for catheter removal was 2.75 (95% confidence interval [95%CI] = 1.25–6.04) for the 1.0‐mg tPA cohort compared with the 2.0‐mg tPA cohort. Correction added on 3 December 2012, after first online publication: The tPA cohort values were changed. Female gender (HR = 2.51; 95%CI = 1.20–5.27) and age (HR = 0.96; 95%CI = 0.94–0.98) were also associated with catheter survival. Our findings suggest that treatment of dysfunctional HDC with 2.0‐mg tPA dwells is superior to 1.0‐mg tPA dwells. 相似文献
178.
Simulation of a localized heating system for broiler brooding to improve energy performance
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The aim of this work is to evaluate the performance of an innovative localized solar‐assisted pen heating system for brooding using a 3D computational simulation model of the heated space. The warm air‐curtained pen ensures acceptable temperature, air velocity, relative humidity, and air quality that meet the ventilation and heat requirements for a typical pen of 100 chicks as recommended by the American Society of Heating Refrigeration and Air Conditioning Engineers and American Society of Agricultural and Biological Engineers. The supply flow characteristics and the simulated velocity and temperature field of the curtained region were determined such that they meet the ventilation requirements and comfort criteria. Results show that air supplied at 40°C is capable of delivering the desired microenvironment at bird level while the heat input to the unit is 685 W when outdoor temperature is ?5°C. The system's energy performance was then analyzed using a prototype of 16 pens. The energy consumption of the new heating scheme consumed one third of the energy required by conventional non‐localized system. Moreover, integrating the new design with a solar system utilizing parabolic concentrators provided 72% of the power load from solar energy during a winter flock operation and 100% during other seasons. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
179.
180.