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21.
Space heating is the highest energy consumer in the operation of residential facilities in cold regions. Energy saving measures for efficient space heating operation are thus of paramount importance in efforts to reduce energy consumption in buildings. For effective functioning of space heating systems, efficient facility management coupled with relevant occupant behaviour information is necessary. However, current practice in space heating control is event-driven rather than user-centric, and in most cases relevant occupant information is not incorporated into space heating energy management strategies. This causes system inefficiency during the occupancy phase. For multi-family residential facilities, integrating occupant information within space heating energy management strategies poses several challenges; unlike with commercial facilities, in multi-family facilities occupant behavior does not follow any fixed activity-schedule pattern. In this study, a framework is developed for extracting relevant information about the uncertainties pertaining to occupant patterns (i.e., demand load) in multi-family residential facilities by identifying the factors affecting space heating energy consumption. This is achieved using sensor-based data monitoring during the occupancy phase. Based on the analysis of the monitoring data, a structure is defined for developing an occupant pattern prediction model that can be integrated with energy management strategies to reduce energy usage in multi-family residential facilities. To demonstrate the developed framework, a multi-family residential building in Fort McMurray, Canada, is chosen as a case study. This paper shows that integrating the developed occupant pattern prediction model within space heating energy management strategies can assist facility managers to achieve space heating energy savings in multi-family residential facilities. 相似文献
22.
23.
Mango peel powder supplementation prevents oxidative stress,inflammation, and fibrosis in carbon tetrachloride induced hepatic dysfunction in rats 下载免费PDF全文
24.
Ruhul A. Khan Stephane Salmieri Dominic Dussault Nusrat Sharmin Monique Lacroix 《应用聚合物科学杂志》2012,123(3):1690-1697
Methylcellulose (MC) films were prepared by casting from its 1% aqueous solution containing 0.5% vegetable oil, 0.25% glycerol, and 0.025% Tween®80. Poly(caprolactone) (PCL) films were prepared by compression molding from its granules. Biodegradable composite films were fabricated using MC film as reinforcing agent and PCL as the matrix material by compression molding. One layer of MC film was reinforced with two layers of PCL films. The MC content in the composites was varied from 10 to 50% by weight. Mechanical, barrier, and degradation properties of PCL, MC, and composite films were evaluated. The values of puncture strength (PS), puncture deformation (PD), viscoelasticity (Y) coefficient, and water vapor permeability (WVP) of the composites (50% MC content) were found to be 124.3 N/mm, 3.2 mm, 31%, and 2.6 g·mm/m2·day·kPa, respectively. Oxygen transmission rate (OTR) of PCL, MC, and composites (50% MC) were found to be 175, 25, 22 cc/m2/d, respectively, which indicated that composite films showed significantly lower OTR than PCL films. Degradation tests of the composite films (50% MC) were performed for 6 weeks in aqueous medium (at 25°C), and it was found that composites lost its mass slowly with time. After 6 weeks, mass and PS of the composites were decreased to 13.4 and 12%, respectively. Composite interface was studied by scanning electron microscopy (SEM). The MC film had good adhesion with PCL matrix during compression molding and suggested strong interface of the composite system. SEM image after 6 weeks of degradation showed some openings in the interface and revealed slow degradation of the MC films. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
25.
Nusrat Ahmed Surobhi Abbas Jamalipour 《Wireless Communications and Mobile Computing》2014,14(12):1127-1142
A global trend toward large scale emergencies has placed an emphasis on the achievement of a ubiquitous public safety network. Such a network may be realized over a mobile ad hoc network formed by the handheld mobile devices. Therefore, traffic in the network can be user generated and thus semantic. Unfortunately, none of the traffic management techniques proposed for the underlying network considers the semantic properties of the generated traffic. Therefore, in this paper, we propose a semantic traffic management framework which has two modules: traffic monitoring unit and traffic reduction unit. Although the first module analyzes the semantic traffic to detect an emergency, the latter module removes redundant semantic information for traffic reduction. We have supported the feasibility of the proposed semantic framework through simulation. Simulation results suggest that the framework is capable of accurate and early detection of an emergency as well as traffic reduction while keeping sufficient information to report the emergency. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
26.
Fahmina Zafar Hina Zafar Eram Sharmin S. M. Ashraf Sharif Ahmad 《Journal of Inorganic and Organometallic Polymers and Materials》2011,21(3):646-654
In this paper linseed oil based metallopolyesteramides (Mn(II)-/Co(II)-/Cu(II)-LPEA) containing metals [with half filled (d
5) and partially filled (d
7 and d
9) d orbitals] were synthesized via green route for the application of eco-friendly protective green material. This paper also
described the role of occupancy of d orbitals on the performance of such polymers. The synthesis reaction was carried out in situ through condensation polymerization
among linseed fatty amide diol (HELA), phthalic anhydride and respective metal acetates [M (OCOCH3)2; M = Mn(II), Co(II), Cu(II); different mole ratios] in absence of any harmful organic solvent. The structural determination
(FTIR, 1H-NMR and 13C-NMR), curing, thermal, physico-chemical, physico-mechanical, anticorrosive/chemical resistance, antibacterial properties
of Mn(II)-/Co(II)-/Cu(II)-LPEA were carried out. The curing mechanism of the resin was confirmed by the comparison of FTIR
spectra of uncured and cured resin. The curing mechanism of Mn(II)-/Co(II)-/Cu(II)-LPEA is found to be contrary to that of
reported oil based polymer that involves the lipid autoxidation (slow process) in which driers are required to speed up the
room temperature curing process. The incorporation of metals in Mn(II)-/Co(II)-/Cu(II)-LPEA improved the thermal stability
as compared to virgin linseed oil based polyesteramide (LPEA). Mn(II)-/Co(II)-/Cu(II)-LPEA also show excellent antibacterial
performance against Staphylococcus aureus and Escherichia coli. The observed diversity in material properties suggests that Mn-LPEA may be useful as an eco-friendly protective green material
with thermal stability up to 320–330 °C. 相似文献
27.
Mohammad Kashif Eram Sharmin Fahmina Zafar Sharif Ahmad 《Journal of the American Oil Chemists' Society》2011,88(12):1989-1996
Ricinus communis (RC) oil-based materials are currently receiving increasing attention because of economic and environmental concerns. In
the present work, RC oil—a natural triol has been utilized for the development of an advanced polymeric material—poly(urethane-ricinoleamide)
(PUR) through very simple synthesis and curing strategy, omitting derivatization steps or side reactions, chain extenders
and crosslinkers. The synthesis of PUR was carried out in two steps. The first step is the introduction of an amide group
in the RC oil (89.5% ricinoleic acid) via base catalyzed amidation, which results in N, N-bis (2-hydroxyethyl) ricinoleamide (HERA). The second step is urethanation of HERA by the reaction of toluene-2,4-diisocyanate
(TDI) in minimal possible organic solvent by one-shot technique, which results in the formation of polyurethane along with
amide linkages. The physico-chemical and spectral studies (FT-IR, 1H-NMR and 13C-NMR techniques) confirm these two reactions and the structure of PUR. The resin was cured at ambient temperature without
any cross linker. Solubility of the resin was investigated in different polar and non-polar solvents. Thermo-gravimetric analysis
(TGA)/differential thermal analysis (DTA) and Differential Scanning Calorimetry (DSC) were used to determine the thermal stability
and curing behavior of PUR. An ambient cured ricinoleamide modified polyurethane resin exhibited thermal resistance up to
200–220 °C. 相似文献
28.
Nusrat J. M. Sanghamitra Hiroshi Inaba Susumu Kitagawa Takafumi Ueno 《Journal of Inorganic and Organometallic Polymers and Materials》2013,23(1):50-60
In the last decade, there has been great deal of progress in the study of self-assembly processes of protein assemblies as biotemplates to create and construct one-dimensional arrays of nanocrystalline metals and semiconductors. Successful attempts in fabricating the protein-based bioelectronics could serve as a promising alternative to synthetic template based nanomaterials. Another perspective of protein assemblies is its use in the field of tissue engineering either as scaffold for cell adhesion and proliferation or as a foreign (bio)nanofunctionality to communicate with the macromolecules present in the extracellular or intracellular milieu and participate in the precise control of vital cell functions. Three-dimensionally arranged protein monomers to form bionanotubes are promising in terms of innate biocompatibility, easy bio-conjugation to incorporate multiple functionalities and well-defined nano-scale lengths. Such unique chemical properties of protein assemblies are described in this review. 相似文献
29.
Jamali MK Kazi TG Arain MB Afridi HI Jalbani N Kandhro GA Shah AQ Baig JA 《Journal of hazardous materials》2009,164(2-3):1386-1391
The concentrations of heavy metals (HMs) in plants served to indicate the metal contamination status of the site, and also revealed the abilities of various plant species to take up and accumulate them from the soil dressed with sewage sludge. A study to comprehend the mobility and transport of HMs from soil and soil amended with untreated sewage sludge to different newly breaded varieties of wheat (Anmol, TJ-83, Abadgar and Mehran-89) in Pakistan. A pot-culture experiment was conducted to study the transfer of HMs to wheat grains, grown in soil (control) and soil amended with sewage sludge (test samples). The total and ethylenediaminetetraaceticacid (EDTA)-extractable HMs in agricultural soil and soil amended with domestic sewage sludge (SDWS) and wheat grains were analysed by flame atomic absorption spectrometer/electrothermal atomic absorption spectrometer, prior to microwave-assisted wet acid digestion method. The edible part of wheat plants (grains) from test samples presented high concentration of all HMs understudy (mgkg(-1)). Significant correlations were found between metals in exchangeable fractions of soil and SDWS, with total metals in control and test samples of wheat grains. The bio-concentration factors of all HMs were high in grains of two wheat varieties, TJ-83 and Mehran-89, as compared to other varieties, Anmol and Abadgar grown in the same agricultural plots. 相似文献
30.
To date, long-term preservation approaches have comprised of emulation, migration, normalization, and metadata – or some combination
of these. Most existing work has focussed on applying these approaches to digital objects of a singular media type:
text, HTML, images, video or audio. In this paper, we consider the preservation of composite, mixed-media digital objects,
a rapidly growing class of resources. We describe an integrated, flexible system that we have developed, which leverages existing
tools and services and assists organizations to dynamically discover the optimum preservation strategy as it is required.
The system captures and periodically compares preservation metadata with software and format registries to determine those
objects (or sub-objects) at risk. By making preservation software modules available as Web services and describing them semantically
using a machine-processable ontology (OWL-S), the most appropriate preservation service(s) for each object (or sub-object)
can then be dynamically discovered, composed and invoked by software agents (with optional human input at critical decision-making
steps). The PANIC system successfully illustrates how the growing array of available preservation tools and services can be
integrated to provide a sustainable, collaborative solution to the long-term preservation of large-scale collections of complex
digital objects. 相似文献