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11.
The current state of the art in applied decomposition techniques is summarized within a comparative uniform framework. These techniques are classified by the parametric or information theoretic approaches they adopt. An underlying structural model common to all parametric approaches is outlined. The nature and premises of a typical information theoretic approach are stressed. Some possible application patterns for an information theoretic approach are illustrated. Composition is distinguished from decomposition by pointing out that the former is not a simple reversal of the latter. From the standpoint of application to complex systems, a general evaluation is provided. 相似文献
12.
Kaan Varnali Cengiz Yilmaz Aysegul Toker 《Electronic Commerce Research and Applications》2012,11(6):570-581
The study examines consumer responses to SMS-based mobile advertising campaigns using a field experiment with actual behavioral responses. Specifically, the effects of message characteristics (i.e., incentives and prior permission) and individual differences of message recipients (i.e., content involvement, prior experience with the mobile medium, and medium-fit perceptions) on the attitudinal and behavioral outcomes of such campaigns are investigated. Perceived intrusiveness of the message and attitude toward the campaign are conceptualized as key attitudinal reactions triggered by a mobile advertising message, which in turn influence the behavioral responses generated by the campaign. Findings suggest that, in comparison to permission and incentive, individual differences are stronger determinants of responses to mobile advertising campaigns. Additionally, intriguing insights with respect to the effectiveness of different types of incentives are provided. 相似文献
13.
A process model for component-oriented software engineering 总被引:1,自引:0,他引:1
The investigation of reuse has a long history, eventually maturing into the "build by integration" paradigm. Meanwhile, component technologies also improved along with engineering practices. What is missing is a methodology that uses components within such a paradigm, thus bridging the gap. The authors propose a model devoted to complete component orientation, rather than modifying object-oriented approaches to accommodate components. They investigate component-based technologies to address new needs and, consequently, to integrate adequate practices toward a consistent process model. 相似文献
14.
Haydar Cukurtepe Massimo Tornatore Aysegul Yayimli Biswanath Mukherjee 《Photonic Network Communications》2014,27(3):154-166
In mixed-line-rate (MLR) networks, different line rates on different wavelengths can coexist on the same fiber. MLR architectures can be built over transparent optical networks, where the transmitted signals remain in the optical domain along the entire path. Along the transparent optical path, a signal experiences various physical layer impairments (PLIs), and its quality degrades as it travels through each optical component. One of the major factors that affect the transmission quality is the launch power of the optical signal. The power must be large enough to ensure noise resiliency at the receiver, but it must be below the limit where fiber nonlinearities distort the signal. Moreover, high launch power is disruptive not only for the actual lightpath itself but also for neighboring lightpaths, and this effect is particularly critical in MLR networks since advanced modulation techniques used for high line rates are highly susceptible to PLIs. In this study, we investigate the problem of determining the appropriate launch power for provisioning of dynamic connection requests in MLR networks. By setting the appropriate launch power for each connection, we aim to maximize the number of established connections. We propose two different heuristics to determine the appropriate launch power of a lightpath. Worst-case best-case average (WBA) is based on optical reach of signal in a transparent optical network. In impairment-aware launch power determination (I-ALPD), current state of the network and impairments are evaluated to determine the launch power. The proposed approaches are practical and can adapt to the needs of network operators. Simulation results show that the performances of the proposed approaches show better results than the existing schemes in terms of blocking probability and bandwidth blocking ratio. 相似文献
15.
In this study, after production by recombinant Bacillus subtilis (BGSC-1A751), carrying pHV1431::subc gene in the complex medium and separation of solids from the fermentation broth, serine alkaline protease (SAP) was dried in order to investigate the stabilization during spray drying and subsequent storage. The effect of air inlet temperature of the spray dryer between T = 70 and 130°C and the effect of protective additives, glucose and maltodextrin, at 0–2% (w/v) on SAP activity during spray drying and storage stability of obtained SAP powders at 4°C for a long period (6 months) were evaluated. Increasing drying air inlet temperature generally resulted in an increase in activity loss; moreover, higher absorbance peaks observed at wave number 1061 cm?1 of the IR spectrums when drying temperature is increased indicates the structural change in the SAP molecule. In most cases presence of additives provided higher activities both after drying and during storage period compared to no additive case. Drying the enzyme with 1% (w/v) glucose at T = 110°C resulted in the highest enzyme activity after drying and storage processes. 相似文献
16.
Analysis and modelling of land-based nutrient pollution by watershed models coupled with GIS: a case study from Turkey. 总被引:1,自引:0,他引:1
A Erturk M Gurel E Varol A Ekdal M Baloch T Dikerler D Z Seker A Tanik 《Water science and technology》2007,55(3):115-122
Diffuse pollution is usually temporally and spatially uncertain, and thus hard to analyze. In many cases, discretizing a diffuse source of pollution into individual point sources can ease diffuse pollution modelling and analysis, and therefore reduce high uncertainty especially in the spatial distribution of pollution loads. This is however a difficult task, since quite a number of sub-drainage areas, with complex structures and land-use properties, has to be delineated. Watershed models can be used to delineate the sub-drainage areas in a watershed with high accuracy and locate the related outlets which connect the sub-drainage areas to the main waterbody in a watershed. In this study, such an approach has been used on a case study to model the diffuse nutrient loads carried to streams that reach to a medium-sized lake in Turkey. The annual nutrient loads, which were calculated by using mathematical models, were then converted to a load-map with the help of a geographical information system. 相似文献
17.
18.
Aysegul Kahraman 《Journal of Materials Science: Materials in Electronics》2018,29(10):7993-8001
The purpose of this study is to understand the effects of substrate temperature (ST) and post deposition annealing (PDA) on the structural-electrical properties of Gd2O3 film and to evaluate the electrical performances of the MOS based devices formed with this dielectric. The Gd2O3/Si structures were annealed at 500, 600, 700, and 800 °C under N2 ambient after the films were grown on heated p-Si substrate at various temperatures ranged from 20 to 300 °C by RF magnetron sputtering. For any given ST, the crystallization/grain size increased with increasing PDA temperature. The bump in the accumulation region or continuous decrease in the capacitance values of the inversion region of the C–V curves for 800 °C PDA was not observed. The lowest effective oxide charge density (Q eff ) value was obtained to be ??1.13?×?1011 cm?2 from the MOS capacitor with Gd2O3, which is grown on heated Si at 300 °C and annealed at 800 °C. The density of the interface states (D it ) was found to be in the range of 0.84?×?1011 to 1.50?×?1011 eV?1 cm?2. The highest dielectric constant (ε) and barrier height \(({\Phi _B})\) values were found to be 14.46 and 3.68, which are obtained for 20 °C ST and 800 °C PDA. The results show that the negative charge trapping in the oxide layer is generally more than that of the positive, but, it is reverse of this situation at the interface. The leakage current density decreased after 20 °C ST, but no significant change was observed for other ST values. 相似文献
19.
Ari E Kaya Y Demir H Cebi A Alp HH Bakan E Odabasi D Keskin S 《Hemodialysis international. International Symposium on Home Hemodialysis》2011,15(4):453-459
Oxidative stress is accepted as a nonclassical cardiovascular risk factor in chronic renal failure patients. The aim of this study was to evaluate the relation between oxidative DNA damage (8‐hydroxy‐2′‐deoxyguanosine/deoxyguanosine [8‐OHdG/dG] ratio), oxidative stress biomarkers, antioxidant enzymes, and carotid artery intima‐media thickness (CIMT) in hemodialysis (HD) patients. Forty chronic HD patients without known atherosclerotic disease and 48 age‐ and sex‐matched healthy individuals were included in the study. Plasma malondialdehyde (MDA) levels and 8‐OHdG/dG ratio were determined as oxidative stress markers. Superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities were measured as antioxidants. CIMT was assessed by carotid artery ultrasonography. 8‐OHdG/dG ratios and MDA levels were higher; SOD and GPx activities were lower in HD patients compared to controls. HD patients had significantly higher CIMT compared to controls (0.61 ± 0.08 vs. 0.42 ± 0.05, p < 0.001). There was a significant positive correlation between CIMT and 8‐OHdG/dG ratio (r = 0.57, p < 0.01) and MDA levels (r = 0.41, p < 0.01), while there was a significant negative correlation between CIMT and SOD (r = ?0.47, p < 0.01) and GPx levels (r = ?0.62, p < 0.01). It is firstly demonstrated that CIMT is positively correlated with oxidative DNA damage in HD patients without known atherosclerotic disease. 相似文献
20.